| /* |
| * Copyright (C) 2007 Oracle. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public |
| * License v2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public |
| * License along with this program; if not, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 021110-1307, USA. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/bio.h> |
| #include <linux/buffer_head.h> |
| #include <linux/file.h> |
| #include <linux/fs.h> |
| #include <linux/pagemap.h> |
| #include <linux/highmem.h> |
| #include <linux/time.h> |
| #include <linux/init.h> |
| #include <linux/string.h> |
| #include <linux/backing-dev.h> |
| #include <linux/mpage.h> |
| #include <linux/swap.h> |
| #include <linux/writeback.h> |
| #include <linux/statfs.h> |
| #include <linux/compat.h> |
| #include <linux/bit_spinlock.h> |
| #include <linux/xattr.h> |
| #include <linux/posix_acl.h> |
| #include <linux/falloc.h> |
| #include <linux/slab.h> |
| #include <linux/ratelimit.h> |
| #include <linux/mount.h> |
| #include "compat.h" |
| #include "ctree.h" |
| #include "disk-io.h" |
| #include "transaction.h" |
| #include "btrfs_inode.h" |
| #include "ioctl.h" |
| #include "print-tree.h" |
| #include "ordered-data.h" |
| #include "xattr.h" |
| #include "tree-log.h" |
| #include "volumes.h" |
| #include "compression.h" |
| #include "locking.h" |
| #include "free-space-cache.h" |
| #include "inode-map.h" |
| |
| struct btrfs_iget_args { |
| u64 ino; |
| struct btrfs_root *root; |
| }; |
| |
| static const struct inode_operations btrfs_dir_inode_operations; |
| static const struct inode_operations btrfs_symlink_inode_operations; |
| static const struct inode_operations btrfs_dir_ro_inode_operations; |
| static const struct inode_operations btrfs_special_inode_operations; |
| static const struct inode_operations btrfs_file_inode_operations; |
| static const struct address_space_operations btrfs_aops; |
| static const struct address_space_operations btrfs_symlink_aops; |
| static const struct file_operations btrfs_dir_file_operations; |
| static struct extent_io_ops btrfs_extent_io_ops; |
| |
| static struct kmem_cache *btrfs_inode_cachep; |
| struct kmem_cache *btrfs_trans_handle_cachep; |
| struct kmem_cache *btrfs_transaction_cachep; |
| struct kmem_cache *btrfs_path_cachep; |
| struct kmem_cache *btrfs_free_space_cachep; |
| |
| #define S_SHIFT 12 |
| static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { |
| [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, |
| [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, |
| [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, |
| [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, |
| [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, |
| [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, |
| [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, |
| }; |
| |
| static int btrfs_setsize(struct inode *inode, loff_t newsize); |
| static int btrfs_truncate(struct inode *inode); |
| static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end); |
| static noinline int cow_file_range(struct inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written, int unlock); |
| static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode); |
| |
| static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, |
| struct inode *inode, struct inode *dir, |
| const struct qstr *qstr) |
| { |
| int err; |
| |
| err = btrfs_init_acl(trans, inode, dir); |
| if (!err) |
| err = btrfs_xattr_security_init(trans, inode, dir, qstr); |
| return err; |
| } |
| |
| /* |
| * this does all the hard work for inserting an inline extent into |
| * the btree. The caller should have done a btrfs_drop_extents so that |
| * no overlapping inline items exist in the btree |
| */ |
| static noinline int insert_inline_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| u64 start, size_t size, size_t compressed_size, |
| int compress_type, |
| struct page **compressed_pages) |
| { |
| struct btrfs_key key; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct page *page = NULL; |
| char *kaddr; |
| unsigned long ptr; |
| struct btrfs_file_extent_item *ei; |
| int err = 0; |
| int ret; |
| size_t cur_size = size; |
| size_t datasize; |
| unsigned long offset; |
| |
| if (compressed_size && compressed_pages) |
| cur_size = compressed_size; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| path->leave_spinning = 1; |
| |
| key.objectid = btrfs_ino(inode); |
| key.offset = start; |
| btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); |
| datasize = btrfs_file_extent_calc_inline_size(cur_size); |
| |
| inode_add_bytes(inode, size); |
| ret = btrfs_insert_empty_item(trans, root, path, &key, |
| datasize); |
| if (ret) { |
| err = ret; |
| goto fail; |
| } |
| leaf = path->nodes[0]; |
| ei = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| btrfs_set_file_extent_generation(leaf, ei, trans->transid); |
| btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); |
| btrfs_set_file_extent_encryption(leaf, ei, 0); |
| btrfs_set_file_extent_other_encoding(leaf, ei, 0); |
| btrfs_set_file_extent_ram_bytes(leaf, ei, size); |
| ptr = btrfs_file_extent_inline_start(ei); |
| |
| if (compress_type != BTRFS_COMPRESS_NONE) { |
| struct page *cpage; |
| int i = 0; |
| while (compressed_size > 0) { |
| cpage = compressed_pages[i]; |
| cur_size = min_t(unsigned long, compressed_size, |
| PAGE_CACHE_SIZE); |
| |
| kaddr = kmap_atomic(cpage); |
| write_extent_buffer(leaf, kaddr, ptr, cur_size); |
| kunmap_atomic(kaddr); |
| |
| i++; |
| ptr += cur_size; |
| compressed_size -= cur_size; |
| } |
| btrfs_set_file_extent_compression(leaf, ei, |
| compress_type); |
| } else { |
| page = find_get_page(inode->i_mapping, |
| start >> PAGE_CACHE_SHIFT); |
| btrfs_set_file_extent_compression(leaf, ei, 0); |
| kaddr = kmap_atomic(page); |
| offset = start & (PAGE_CACHE_SIZE - 1); |
| write_extent_buffer(leaf, kaddr + offset, ptr, size); |
| kunmap_atomic(kaddr); |
| page_cache_release(page); |
| } |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_free_path(path); |
| |
| /* |
| * we're an inline extent, so nobody can |
| * extend the file past i_size without locking |
| * a page we already have locked. |
| * |
| * We must do any isize and inode updates |
| * before we unlock the pages. Otherwise we |
| * could end up racing with unlink. |
| */ |
| BTRFS_I(inode)->disk_i_size = inode->i_size; |
| ret = btrfs_update_inode(trans, root, inode); |
| |
| return ret; |
| fail: |
| btrfs_free_path(path); |
| return err; |
| } |
| |
| |
| /* |
| * conditionally insert an inline extent into the file. This |
| * does the checks required to make sure the data is small enough |
| * to fit as an inline extent. |
| */ |
| static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *inode, u64 start, u64 end, |
| size_t compressed_size, int compress_type, |
| struct page **compressed_pages) |
| { |
| u64 isize = i_size_read(inode); |
| u64 actual_end = min(end + 1, isize); |
| u64 inline_len = actual_end - start; |
| u64 aligned_end = (end + root->sectorsize - 1) & |
| ~((u64)root->sectorsize - 1); |
| u64 hint_byte; |
| u64 data_len = inline_len; |
| int ret; |
| |
| if (compressed_size) |
| data_len = compressed_size; |
| |
| if (start > 0 || |
| actual_end >= PAGE_CACHE_SIZE || |
| data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) || |
| (!compressed_size && |
| (actual_end & (root->sectorsize - 1)) == 0) || |
| end + 1 < isize || |
| data_len > root->fs_info->max_inline) { |
| return 1; |
| } |
| |
| ret = btrfs_drop_extents(trans, inode, start, aligned_end, |
| &hint_byte, 1); |
| if (ret) |
| return ret; |
| |
| if (isize > actual_end) |
| inline_len = min_t(u64, isize, actual_end); |
| ret = insert_inline_extent(trans, root, inode, start, |
| inline_len, compressed_size, |
| compress_type, compressed_pages); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| return ret; |
| } |
| btrfs_delalloc_release_metadata(inode, end + 1 - start); |
| btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0); |
| return 0; |
| } |
| |
| struct async_extent { |
| u64 start; |
| u64 ram_size; |
| u64 compressed_size; |
| struct page **pages; |
| unsigned long nr_pages; |
| int compress_type; |
| struct list_head list; |
| }; |
| |
| struct async_cow { |
| struct inode *inode; |
| struct btrfs_root *root; |
| struct page *locked_page; |
| u64 start; |
| u64 end; |
| struct list_head extents; |
| struct btrfs_work work; |
| }; |
| |
| static noinline int add_async_extent(struct async_cow *cow, |
| u64 start, u64 ram_size, |
| u64 compressed_size, |
| struct page **pages, |
| unsigned long nr_pages, |
| int compress_type) |
| { |
| struct async_extent *async_extent; |
| |
| async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); |
| BUG_ON(!async_extent); /* -ENOMEM */ |
| async_extent->start = start; |
| async_extent->ram_size = ram_size; |
| async_extent->compressed_size = compressed_size; |
| async_extent->pages = pages; |
| async_extent->nr_pages = nr_pages; |
| async_extent->compress_type = compress_type; |
| list_add_tail(&async_extent->list, &cow->extents); |
| return 0; |
| } |
| |
| /* |
| * we create compressed extents in two phases. The first |
| * phase compresses a range of pages that have already been |
| * locked (both pages and state bits are locked). |
| * |
| * This is done inside an ordered work queue, and the compression |
| * is spread across many cpus. The actual IO submission is step |
| * two, and the ordered work queue takes care of making sure that |
| * happens in the same order things were put onto the queue by |
| * writepages and friends. |
| * |
| * If this code finds it can't get good compression, it puts an |
| * entry onto the work queue to write the uncompressed bytes. This |
| * makes sure that both compressed inodes and uncompressed inodes |
| * are written in the same order that pdflush sent them down. |
| */ |
| static noinline int compress_file_range(struct inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, |
| struct async_cow *async_cow, |
| int *num_added) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| u64 num_bytes; |
| u64 blocksize = root->sectorsize; |
| u64 actual_end; |
| u64 isize = i_size_read(inode); |
| int ret = 0; |
| struct page **pages = NULL; |
| unsigned long nr_pages; |
| unsigned long nr_pages_ret = 0; |
| unsigned long total_compressed = 0; |
| unsigned long total_in = 0; |
| unsigned long max_compressed = 128 * 1024; |
| unsigned long max_uncompressed = 128 * 1024; |
| int i; |
| int will_compress; |
| int compress_type = root->fs_info->compress_type; |
| |
| /* if this is a small write inside eof, kick off a defrag */ |
| if ((end - start + 1) < 16 * 1024 && |
| (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) |
| btrfs_add_inode_defrag(NULL, inode); |
| |
| actual_end = min_t(u64, isize, end + 1); |
| again: |
| will_compress = 0; |
| nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1; |
| nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE); |
| |
| /* |
| * we don't want to send crud past the end of i_size through |
| * compression, that's just a waste of CPU time. So, if the |
| * end of the file is before the start of our current |
| * requested range of bytes, we bail out to the uncompressed |
| * cleanup code that can deal with all of this. |
| * |
| * It isn't really the fastest way to fix things, but this is a |
| * very uncommon corner. |
| */ |
| if (actual_end <= start) |
| goto cleanup_and_bail_uncompressed; |
| |
| total_compressed = actual_end - start; |
| |
| /* we want to make sure that amount of ram required to uncompress |
| * an extent is reasonable, so we limit the total size in ram |
| * of a compressed extent to 128k. This is a crucial number |
| * because it also controls how easily we can spread reads across |
| * cpus for decompression. |
| * |
| * We also want to make sure the amount of IO required to do |
| * a random read is reasonably small, so we limit the size of |
| * a compressed extent to 128k. |
| */ |
| total_compressed = min(total_compressed, max_uncompressed); |
| num_bytes = (end - start + blocksize) & ~(blocksize - 1); |
| num_bytes = max(blocksize, num_bytes); |
| total_in = 0; |
| ret = 0; |
| |
| /* |
| * we do compression for mount -o compress and when the |
| * inode has not been flagged as nocompress. This flag can |
| * change at any time if we discover bad compression ratios. |
| */ |
| if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) && |
| (btrfs_test_opt(root, COMPRESS) || |
| (BTRFS_I(inode)->force_compress) || |
| (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) { |
| WARN_ON(pages); |
| pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); |
| if (!pages) { |
| /* just bail out to the uncompressed code */ |
| goto cont; |
| } |
| |
| if (BTRFS_I(inode)->force_compress) |
| compress_type = BTRFS_I(inode)->force_compress; |
| |
| ret = btrfs_compress_pages(compress_type, |
| inode->i_mapping, start, |
| total_compressed, pages, |
| nr_pages, &nr_pages_ret, |
| &total_in, |
| &total_compressed, |
| max_compressed); |
| |
| if (!ret) { |
| unsigned long offset = total_compressed & |
| (PAGE_CACHE_SIZE - 1); |
| struct page *page = pages[nr_pages_ret - 1]; |
| char *kaddr; |
| |
| /* zero the tail end of the last page, we might be |
| * sending it down to disk |
| */ |
| if (offset) { |
| kaddr = kmap_atomic(page); |
| memset(kaddr + offset, 0, |
| PAGE_CACHE_SIZE - offset); |
| kunmap_atomic(kaddr); |
| } |
| will_compress = 1; |
| } |
| } |
| cont: |
| if (start == 0) { |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| trans = NULL; |
| goto cleanup_and_out; |
| } |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| /* lets try to make an inline extent */ |
| if (ret || total_in < (actual_end - start)) { |
| /* we didn't compress the entire range, try |
| * to make an uncompressed inline extent. |
| */ |
| ret = cow_file_range_inline(trans, root, inode, |
| start, end, 0, 0, NULL); |
| } else { |
| /* try making a compressed inline extent */ |
| ret = cow_file_range_inline(trans, root, inode, |
| start, end, |
| total_compressed, |
| compress_type, pages); |
| } |
| if (ret <= 0) { |
| /* |
| * inline extent creation worked or returned error, |
| * we don't need to create any more async work items. |
| * Unlock and free up our temp pages. |
| */ |
| extent_clear_unlock_delalloc(inode, |
| &BTRFS_I(inode)->io_tree, |
| start, end, NULL, |
| EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK); |
| |
| btrfs_end_transaction(trans, root); |
| goto free_pages_out; |
| } |
| btrfs_end_transaction(trans, root); |
| } |
| |
| if (will_compress) { |
| /* |
| * we aren't doing an inline extent round the compressed size |
| * up to a block size boundary so the allocator does sane |
| * things |
| */ |
| total_compressed = (total_compressed + blocksize - 1) & |
| ~(blocksize - 1); |
| |
| /* |
| * one last check to make sure the compression is really a |
| * win, compare the page count read with the blocks on disk |
| */ |
| total_in = (total_in + PAGE_CACHE_SIZE - 1) & |
| ~(PAGE_CACHE_SIZE - 1); |
| if (total_compressed >= total_in) { |
| will_compress = 0; |
| } else { |
| num_bytes = total_in; |
| } |
| } |
| if (!will_compress && pages) { |
| /* |
| * the compression code ran but failed to make things smaller, |
| * free any pages it allocated and our page pointer array |
| */ |
| for (i = 0; i < nr_pages_ret; i++) { |
| WARN_ON(pages[i]->mapping); |
| page_cache_release(pages[i]); |
| } |
| kfree(pages); |
| pages = NULL; |
| total_compressed = 0; |
| nr_pages_ret = 0; |
| |
| /* flag the file so we don't compress in the future */ |
| if (!btrfs_test_opt(root, FORCE_COMPRESS) && |
| !(BTRFS_I(inode)->force_compress)) { |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; |
| } |
| } |
| if (will_compress) { |
| *num_added += 1; |
| |
| /* the async work queues will take care of doing actual |
| * allocation on disk for these compressed pages, |
| * and will submit them to the elevator. |
| */ |
| add_async_extent(async_cow, start, num_bytes, |
| total_compressed, pages, nr_pages_ret, |
| compress_type); |
| |
| if (start + num_bytes < end) { |
| start += num_bytes; |
| pages = NULL; |
| cond_resched(); |
| goto again; |
| } |
| } else { |
| cleanup_and_bail_uncompressed: |
| /* |
| * No compression, but we still need to write the pages in |
| * the file we've been given so far. redirty the locked |
| * page if it corresponds to our extent and set things up |
| * for the async work queue to run cow_file_range to do |
| * the normal delalloc dance |
| */ |
| if (page_offset(locked_page) >= start && |
| page_offset(locked_page) <= end) { |
| __set_page_dirty_nobuffers(locked_page); |
| /* unlocked later on in the async handlers */ |
| } |
| add_async_extent(async_cow, start, end - start + 1, |
| 0, NULL, 0, BTRFS_COMPRESS_NONE); |
| *num_added += 1; |
| } |
| |
| out: |
| return ret; |
| |
| free_pages_out: |
| for (i = 0; i < nr_pages_ret; i++) { |
| WARN_ON(pages[i]->mapping); |
| page_cache_release(pages[i]); |
| } |
| kfree(pages); |
| |
| goto out; |
| |
| cleanup_and_out: |
| extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, |
| start, end, NULL, |
| EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_DIRTY | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_SET_WRITEBACK | |
| EXTENT_END_WRITEBACK); |
| if (!trans || IS_ERR(trans)) |
| btrfs_error(root->fs_info, ret, "Failed to join transaction"); |
| else |
| btrfs_abort_transaction(trans, root, ret); |
| goto free_pages_out; |
| } |
| |
| /* |
| * phase two of compressed writeback. This is the ordered portion |
| * of the code, which only gets called in the order the work was |
| * queued. We walk all the async extents created by compress_file_range |
| * and send them down to the disk. |
| */ |
| static noinline int submit_compressed_extents(struct inode *inode, |
| struct async_cow *async_cow) |
| { |
| struct async_extent *async_extent; |
| u64 alloc_hint = 0; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_key ins; |
| struct extent_map *em; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct extent_io_tree *io_tree; |
| int ret = 0; |
| |
| if (list_empty(&async_cow->extents)) |
| return 0; |
| |
| |
| while (!list_empty(&async_cow->extents)) { |
| async_extent = list_entry(async_cow->extents.next, |
| struct async_extent, list); |
| list_del(&async_extent->list); |
| |
| io_tree = &BTRFS_I(inode)->io_tree; |
| |
| retry: |
| /* did the compression code fall back to uncompressed IO? */ |
| if (!async_extent->pages) { |
| int page_started = 0; |
| unsigned long nr_written = 0; |
| |
| lock_extent(io_tree, async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1); |
| |
| /* allocate blocks */ |
| ret = cow_file_range(inode, async_cow->locked_page, |
| async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1, |
| &page_started, &nr_written, 0); |
| |
| /* JDM XXX */ |
| |
| /* |
| * if page_started, cow_file_range inserted an |
| * inline extent and took care of all the unlocking |
| * and IO for us. Otherwise, we need to submit |
| * all those pages down to the drive. |
| */ |
| if (!page_started && !ret) |
| extent_write_locked_range(io_tree, |
| inode, async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1, |
| btrfs_get_extent, |
| WB_SYNC_ALL); |
| kfree(async_extent); |
| cond_resched(); |
| continue; |
| } |
| |
| lock_extent(io_tree, async_extent->start, |
| async_extent->start + async_extent->ram_size - 1); |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| } else { |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| ret = btrfs_reserve_extent(trans, root, |
| async_extent->compressed_size, |
| async_extent->compressed_size, |
| 0, alloc_hint, &ins, 1); |
| if (ret) |
| btrfs_abort_transaction(trans, root, ret); |
| btrfs_end_transaction(trans, root); |
| } |
| |
| if (ret) { |
| int i; |
| for (i = 0; i < async_extent->nr_pages; i++) { |
| WARN_ON(async_extent->pages[i]->mapping); |
| page_cache_release(async_extent->pages[i]); |
| } |
| kfree(async_extent->pages); |
| async_extent->nr_pages = 0; |
| async_extent->pages = NULL; |
| unlock_extent(io_tree, async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1); |
| if (ret == -ENOSPC) |
| goto retry; |
| goto out_free; /* JDM: Requeue? */ |
| } |
| |
| /* |
| * here we're doing allocation and writeback of the |
| * compressed pages |
| */ |
| btrfs_drop_extent_cache(inode, async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1, 0); |
| |
| em = alloc_extent_map(); |
| BUG_ON(!em); /* -ENOMEM */ |
| em->start = async_extent->start; |
| em->len = async_extent->ram_size; |
| em->orig_start = em->start; |
| |
| em->block_start = ins.objectid; |
| em->block_len = ins.offset; |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| em->compress_type = async_extent->compress_type; |
| set_bit(EXTENT_FLAG_PINNED, &em->flags); |
| set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
| |
| while (1) { |
| write_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| write_unlock(&em_tree->lock); |
| if (ret != -EEXIST) { |
| free_extent_map(em); |
| break; |
| } |
| btrfs_drop_extent_cache(inode, async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1, 0); |
| } |
| |
| ret = btrfs_add_ordered_extent_compress(inode, |
| async_extent->start, |
| ins.objectid, |
| async_extent->ram_size, |
| ins.offset, |
| BTRFS_ORDERED_COMPRESSED, |
| async_extent->compress_type); |
| BUG_ON(ret); /* -ENOMEM */ |
| |
| /* |
| * clear dirty, set writeback and unlock the pages. |
| */ |
| extent_clear_unlock_delalloc(inode, |
| &BTRFS_I(inode)->io_tree, |
| async_extent->start, |
| async_extent->start + |
| async_extent->ram_size - 1, |
| NULL, EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_UNLOCK | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK); |
| |
| ret = btrfs_submit_compressed_write(inode, |
| async_extent->start, |
| async_extent->ram_size, |
| ins.objectid, |
| ins.offset, async_extent->pages, |
| async_extent->nr_pages); |
| |
| BUG_ON(ret); /* -ENOMEM */ |
| alloc_hint = ins.objectid + ins.offset; |
| kfree(async_extent); |
| cond_resched(); |
| } |
| ret = 0; |
| out: |
| return ret; |
| out_free: |
| kfree(async_extent); |
| goto out; |
| } |
| |
| static u64 get_extent_allocation_hint(struct inode *inode, u64 start, |
| u64 num_bytes) |
| { |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct extent_map *em; |
| u64 alloc_hint = 0; |
| |
| read_lock(&em_tree->lock); |
| em = search_extent_mapping(em_tree, start, num_bytes); |
| if (em) { |
| /* |
| * if block start isn't an actual block number then find the |
| * first block in this inode and use that as a hint. If that |
| * block is also bogus then just don't worry about it. |
| */ |
| if (em->block_start >= EXTENT_MAP_LAST_BYTE) { |
| free_extent_map(em); |
| em = search_extent_mapping(em_tree, 0, 0); |
| if (em && em->block_start < EXTENT_MAP_LAST_BYTE) |
| alloc_hint = em->block_start; |
| if (em) |
| free_extent_map(em); |
| } else { |
| alloc_hint = em->block_start; |
| free_extent_map(em); |
| } |
| } |
| read_unlock(&em_tree->lock); |
| |
| return alloc_hint; |
| } |
| |
| /* |
| * when extent_io.c finds a delayed allocation range in the file, |
| * the call backs end up in this code. The basic idea is to |
| * allocate extents on disk for the range, and create ordered data structs |
| * in ram to track those extents. |
| * |
| * locked_page is the page that writepage had locked already. We use |
| * it to make sure we don't do extra locks or unlocks. |
| * |
| * *page_started is set to one if we unlock locked_page and do everything |
| * required to start IO on it. It may be clean and already done with |
| * IO when we return. |
| */ |
| static noinline int cow_file_range(struct inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written, |
| int unlock) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| u64 alloc_hint = 0; |
| u64 num_bytes; |
| unsigned long ram_size; |
| u64 disk_num_bytes; |
| u64 cur_alloc_size; |
| u64 blocksize = root->sectorsize; |
| struct btrfs_key ins; |
| struct extent_map *em; |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| int ret = 0; |
| |
| BUG_ON(btrfs_is_free_space_inode(root, inode)); |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| extent_clear_unlock_delalloc(inode, |
| &BTRFS_I(inode)->io_tree, |
| start, end, NULL, |
| EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_UNLOCK | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_CLEAR_DIRTY | |
| EXTENT_SET_WRITEBACK | |
| EXTENT_END_WRITEBACK); |
| return PTR_ERR(trans); |
| } |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| num_bytes = (end - start + blocksize) & ~(blocksize - 1); |
| num_bytes = max(blocksize, num_bytes); |
| disk_num_bytes = num_bytes; |
| ret = 0; |
| |
| /* if this is a small write inside eof, kick off defrag */ |
| if (num_bytes < 64 * 1024 && |
| (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) |
| btrfs_add_inode_defrag(trans, inode); |
| |
| if (start == 0) { |
| /* lets try to make an inline extent */ |
| ret = cow_file_range_inline(trans, root, inode, |
| start, end, 0, 0, NULL); |
| if (ret == 0) { |
| extent_clear_unlock_delalloc(inode, |
| &BTRFS_I(inode)->io_tree, |
| start, end, NULL, |
| EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_UNLOCK | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_CLEAR_DIRTY | |
| EXTENT_SET_WRITEBACK | |
| EXTENT_END_WRITEBACK); |
| |
| *nr_written = *nr_written + |
| (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE; |
| *page_started = 1; |
| goto out; |
| } else if (ret < 0) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_unlock; |
| } |
| } |
| |
| BUG_ON(disk_num_bytes > |
| btrfs_super_total_bytes(root->fs_info->super_copy)); |
| |
| alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); |
| btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); |
| |
| while (disk_num_bytes > 0) { |
| unsigned long op; |
| |
| cur_alloc_size = disk_num_bytes; |
| ret = btrfs_reserve_extent(trans, root, cur_alloc_size, |
| root->sectorsize, 0, alloc_hint, |
| &ins, 1); |
| if (ret < 0) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_unlock; |
| } |
| |
| em = alloc_extent_map(); |
| BUG_ON(!em); /* -ENOMEM */ |
| em->start = start; |
| em->orig_start = em->start; |
| ram_size = ins.offset; |
| em->len = ins.offset; |
| |
| em->block_start = ins.objectid; |
| em->block_len = ins.offset; |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| set_bit(EXTENT_FLAG_PINNED, &em->flags); |
| |
| while (1) { |
| write_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| write_unlock(&em_tree->lock); |
| if (ret != -EEXIST) { |
| free_extent_map(em); |
| break; |
| } |
| btrfs_drop_extent_cache(inode, start, |
| start + ram_size - 1, 0); |
| } |
| |
| cur_alloc_size = ins.offset; |
| ret = btrfs_add_ordered_extent(inode, start, ins.objectid, |
| ram_size, cur_alloc_size, 0); |
| BUG_ON(ret); /* -ENOMEM */ |
| |
| if (root->root_key.objectid == |
| BTRFS_DATA_RELOC_TREE_OBJECTID) { |
| ret = btrfs_reloc_clone_csums(inode, start, |
| cur_alloc_size); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_unlock; |
| } |
| } |
| |
| if (disk_num_bytes < cur_alloc_size) |
| break; |
| |
| /* we're not doing compressed IO, don't unlock the first |
| * page (which the caller expects to stay locked), don't |
| * clear any dirty bits and don't set any writeback bits |
| * |
| * Do set the Private2 bit so we know this page was properly |
| * setup for writepage |
| */ |
| op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0; |
| op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | |
| EXTENT_SET_PRIVATE2; |
| |
| extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, |
| start, start + ram_size - 1, |
| locked_page, op); |
| disk_num_bytes -= cur_alloc_size; |
| num_bytes -= cur_alloc_size; |
| alloc_hint = ins.objectid + ins.offset; |
| start += cur_alloc_size; |
| } |
| ret = 0; |
| out: |
| btrfs_end_transaction(trans, root); |
| |
| return ret; |
| out_unlock: |
| extent_clear_unlock_delalloc(inode, |
| &BTRFS_I(inode)->io_tree, |
| start, end, NULL, |
| EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_UNLOCK | |
| EXTENT_CLEAR_DELALLOC | |
| EXTENT_CLEAR_DIRTY | |
| EXTENT_SET_WRITEBACK | |
| EXTENT_END_WRITEBACK); |
| |
| goto out; |
| } |
| |
| /* |
| * work queue call back to started compression on a file and pages |
| */ |
| static noinline void async_cow_start(struct btrfs_work *work) |
| { |
| struct async_cow *async_cow; |
| int num_added = 0; |
| async_cow = container_of(work, struct async_cow, work); |
| |
| compress_file_range(async_cow->inode, async_cow->locked_page, |
| async_cow->start, async_cow->end, async_cow, |
| &num_added); |
| if (num_added == 0) |
| async_cow->inode = NULL; |
| } |
| |
| /* |
| * work queue call back to submit previously compressed pages |
| */ |
| static noinline void async_cow_submit(struct btrfs_work *work) |
| { |
| struct async_cow *async_cow; |
| struct btrfs_root *root; |
| unsigned long nr_pages; |
| |
| async_cow = container_of(work, struct async_cow, work); |
| |
| root = async_cow->root; |
| nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >> |
| PAGE_CACHE_SHIFT; |
| |
| atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages); |
| |
| if (atomic_read(&root->fs_info->async_delalloc_pages) < |
| 5 * 1042 * 1024 && |
| waitqueue_active(&root->fs_info->async_submit_wait)) |
| wake_up(&root->fs_info->async_submit_wait); |
| |
| if (async_cow->inode) |
| submit_compressed_extents(async_cow->inode, async_cow); |
| } |
| |
| static noinline void async_cow_free(struct btrfs_work *work) |
| { |
| struct async_cow *async_cow; |
| async_cow = container_of(work, struct async_cow, work); |
| kfree(async_cow); |
| } |
| |
| static int cow_file_range_async(struct inode *inode, struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written) |
| { |
| struct async_cow *async_cow; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| unsigned long nr_pages; |
| u64 cur_end; |
| int limit = 10 * 1024 * 1042; |
| |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, |
| 1, 0, NULL, GFP_NOFS); |
| while (start < end) { |
| async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); |
| BUG_ON(!async_cow); /* -ENOMEM */ |
| async_cow->inode = inode; |
| async_cow->root = root; |
| async_cow->locked_page = locked_page; |
| async_cow->start = start; |
| |
| if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) |
| cur_end = end; |
| else |
| cur_end = min(end, start + 512 * 1024 - 1); |
| |
| async_cow->end = cur_end; |
| INIT_LIST_HEAD(&async_cow->extents); |
| |
| async_cow->work.func = async_cow_start; |
| async_cow->work.ordered_func = async_cow_submit; |
| async_cow->work.ordered_free = async_cow_free; |
| async_cow->work.flags = 0; |
| |
| nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >> |
| PAGE_CACHE_SHIFT; |
| atomic_add(nr_pages, &root->fs_info->async_delalloc_pages); |
| |
| btrfs_queue_worker(&root->fs_info->delalloc_workers, |
| &async_cow->work); |
| |
| if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) { |
| wait_event(root->fs_info->async_submit_wait, |
| (atomic_read(&root->fs_info->async_delalloc_pages) < |
| limit)); |
| } |
| |
| while (atomic_read(&root->fs_info->async_submit_draining) && |
| atomic_read(&root->fs_info->async_delalloc_pages)) { |
| wait_event(root->fs_info->async_submit_wait, |
| (atomic_read(&root->fs_info->async_delalloc_pages) == |
| 0)); |
| } |
| |
| *nr_written += nr_pages; |
| start = cur_end + 1; |
| } |
| *page_started = 1; |
| return 0; |
| } |
| |
| static noinline int csum_exist_in_range(struct btrfs_root *root, |
| u64 bytenr, u64 num_bytes) |
| { |
| int ret; |
| struct btrfs_ordered_sum *sums; |
| LIST_HEAD(list); |
| |
| ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr, |
| bytenr + num_bytes - 1, &list, 0); |
| if (ret == 0 && list_empty(&list)) |
| return 0; |
| |
| while (!list_empty(&list)) { |
| sums = list_entry(list.next, struct btrfs_ordered_sum, list); |
| list_del(&sums->list); |
| kfree(sums); |
| } |
| return 1; |
| } |
| |
| /* |
| * when nowcow writeback call back. This checks for snapshots or COW copies |
| * of the extents that exist in the file, and COWs the file as required. |
| * |
| * If no cow copies or snapshots exist, we write directly to the existing |
| * blocks on disk |
| */ |
| static noinline int run_delalloc_nocow(struct inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, int force, |
| unsigned long *nr_written) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| struct extent_buffer *leaf; |
| struct btrfs_path *path; |
| struct btrfs_file_extent_item *fi; |
| struct btrfs_key found_key; |
| u64 cow_start; |
| u64 cur_offset; |
| u64 extent_end; |
| u64 extent_offset; |
| u64 disk_bytenr; |
| u64 num_bytes; |
| int extent_type; |
| int ret, err; |
| int type; |
| int nocow; |
| int check_prev = 1; |
| bool nolock; |
| u64 ino = btrfs_ino(inode); |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| nolock = btrfs_is_free_space_inode(root, inode); |
| |
| if (nolock) |
| trans = btrfs_join_transaction_nolock(root); |
| else |
| trans = btrfs_join_transaction(root); |
| |
| if (IS_ERR(trans)) { |
| btrfs_free_path(path); |
| return PTR_ERR(trans); |
| } |
| |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| cow_start = (u64)-1; |
| cur_offset = start; |
| while (1) { |
| ret = btrfs_lookup_file_extent(trans, root, path, ino, |
| cur_offset, 0); |
| if (ret < 0) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto error; |
| } |
| if (ret > 0 && path->slots[0] > 0 && check_prev) { |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, |
| path->slots[0] - 1); |
| if (found_key.objectid == ino && |
| found_key.type == BTRFS_EXTENT_DATA_KEY) |
| path->slots[0]--; |
| } |
| check_prev = 0; |
| next_slot: |
| leaf = path->nodes[0]; |
| if (path->slots[0] >= btrfs_header_nritems(leaf)) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret < 0) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto error; |
| } |
| if (ret > 0) |
| break; |
| leaf = path->nodes[0]; |
| } |
| |
| nocow = 0; |
| disk_bytenr = 0; |
| num_bytes = 0; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| |
| if (found_key.objectid > ino || |
| found_key.type > BTRFS_EXTENT_DATA_KEY || |
| found_key.offset > end) |
| break; |
| |
| if (found_key.offset > cur_offset) { |
| extent_end = found_key.offset; |
| extent_type = 0; |
| goto out_check; |
| } |
| |
| fi = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| extent_type = btrfs_file_extent_type(leaf, fi); |
| |
| if (extent_type == BTRFS_FILE_EXTENT_REG || |
| extent_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); |
| extent_offset = btrfs_file_extent_offset(leaf, fi); |
| extent_end = found_key.offset + |
| btrfs_file_extent_num_bytes(leaf, fi); |
| if (extent_end <= start) { |
| path->slots[0]++; |
| goto next_slot; |
| } |
| if (disk_bytenr == 0) |
| goto out_check; |
| if (btrfs_file_extent_compression(leaf, fi) || |
| btrfs_file_extent_encryption(leaf, fi) || |
| btrfs_file_extent_other_encoding(leaf, fi)) |
| goto out_check; |
| if (extent_type == BTRFS_FILE_EXTENT_REG && !force) |
| goto out_check; |
| if (btrfs_extent_readonly(root, disk_bytenr)) |
| goto out_check; |
| if (btrfs_cross_ref_exist(trans, root, ino, |
| found_key.offset - |
| extent_offset, disk_bytenr)) |
| goto out_check; |
| disk_bytenr += extent_offset; |
| disk_bytenr += cur_offset - found_key.offset; |
| num_bytes = min(end + 1, extent_end) - cur_offset; |
| /* |
| * force cow if csum exists in the range. |
| * this ensure that csum for a given extent are |
| * either valid or do not exist. |
| */ |
| if (csum_exist_in_range(root, disk_bytenr, num_bytes)) |
| goto out_check; |
| nocow = 1; |
| } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { |
| extent_end = found_key.offset + |
| btrfs_file_extent_inline_len(leaf, fi); |
| extent_end = ALIGN(extent_end, root->sectorsize); |
| } else { |
| BUG_ON(1); |
| } |
| out_check: |
| if (extent_end <= start) { |
| path->slots[0]++; |
| goto next_slot; |
| } |
| if (!nocow) { |
| if (cow_start == (u64)-1) |
| cow_start = cur_offset; |
| cur_offset = extent_end; |
| if (cur_offset > end) |
| break; |
| path->slots[0]++; |
| goto next_slot; |
| } |
| |
| btrfs_release_path(path); |
| if (cow_start != (u64)-1) { |
| ret = cow_file_range(inode, locked_page, cow_start, |
| found_key.offset - 1, page_started, |
| nr_written, 1); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto error; |
| } |
| cow_start = (u64)-1; |
| } |
| |
| if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| struct extent_map *em; |
| struct extent_map_tree *em_tree; |
| em_tree = &BTRFS_I(inode)->extent_tree; |
| em = alloc_extent_map(); |
| BUG_ON(!em); /* -ENOMEM */ |
| em->start = cur_offset; |
| em->orig_start = em->start; |
| em->len = num_bytes; |
| em->block_len = num_bytes; |
| em->block_start = disk_bytenr; |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| set_bit(EXTENT_FLAG_PINNED, &em->flags); |
| while (1) { |
| write_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| write_unlock(&em_tree->lock); |
| if (ret != -EEXIST) { |
| free_extent_map(em); |
| break; |
| } |
| btrfs_drop_extent_cache(inode, em->start, |
| em->start + em->len - 1, 0); |
| } |
| type = BTRFS_ORDERED_PREALLOC; |
| } else { |
| type = BTRFS_ORDERED_NOCOW; |
| } |
| |
| ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, |
| num_bytes, num_bytes, type); |
| BUG_ON(ret); /* -ENOMEM */ |
| |
| if (root->root_key.objectid == |
| BTRFS_DATA_RELOC_TREE_OBJECTID) { |
| ret = btrfs_reloc_clone_csums(inode, cur_offset, |
| num_bytes); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto error; |
| } |
| } |
| |
| extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, |
| cur_offset, cur_offset + num_bytes - 1, |
| locked_page, EXTENT_CLEAR_UNLOCK_PAGE | |
| EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | |
| EXTENT_SET_PRIVATE2); |
| cur_offset = extent_end; |
| if (cur_offset > end) |
| break; |
| } |
| btrfs_release_path(path); |
| |
| if (cur_offset <= end && cow_start == (u64)-1) |
| cow_start = cur_offset; |
| if (cow_start != (u64)-1) { |
| ret = cow_file_range(inode, locked_page, cow_start, end, |
| page_started, nr_written, 1); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto error; |
| } |
| } |
| |
| error: |
| if (nolock) { |
| err = btrfs_end_transaction_nolock(trans, root); |
| } else { |
| err = btrfs_end_transaction(trans, root); |
| } |
| if (!ret) |
| ret = err; |
| |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * extent_io.c call back to do delayed allocation processing |
| */ |
| static int run_delalloc_range(struct inode *inode, struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written) |
| { |
| int ret; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| |
| if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) |
| ret = run_delalloc_nocow(inode, locked_page, start, end, |
| page_started, 1, nr_written); |
| else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) |
| ret = run_delalloc_nocow(inode, locked_page, start, end, |
| page_started, 0, nr_written); |
| else if (!btrfs_test_opt(root, COMPRESS) && |
| !(BTRFS_I(inode)->force_compress) && |
| !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) |
| ret = cow_file_range(inode, locked_page, start, end, |
| page_started, nr_written, 1); |
| else |
| ret = cow_file_range_async(inode, locked_page, start, end, |
| page_started, nr_written); |
| return ret; |
| } |
| |
| static void btrfs_split_extent_hook(struct inode *inode, |
| struct extent_state *orig, u64 split) |
| { |
| /* not delalloc, ignore it */ |
| if (!(orig->state & EXTENT_DELALLOC)) |
| return; |
| |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->outstanding_extents++; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| /* |
| * extent_io.c merge_extent_hook, used to track merged delayed allocation |
| * extents so we can keep track of new extents that are just merged onto old |
| * extents, such as when we are doing sequential writes, so we can properly |
| * account for the metadata space we'll need. |
| */ |
| static void btrfs_merge_extent_hook(struct inode *inode, |
| struct extent_state *new, |
| struct extent_state *other) |
| { |
| /* not delalloc, ignore it */ |
| if (!(other->state & EXTENT_DELALLOC)) |
| return; |
| |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->outstanding_extents--; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| /* |
| * extent_io.c set_bit_hook, used to track delayed allocation |
| * bytes in this file, and to maintain the list of inodes that |
| * have pending delalloc work to be done. |
| */ |
| static void btrfs_set_bit_hook(struct inode *inode, |
| struct extent_state *state, int *bits) |
| { |
| |
| /* |
| * set_bit and clear bit hooks normally require _irqsave/restore |
| * but in this case, we are only testing for the DELALLOC |
| * bit, which is only set or cleared with irqs on |
| */ |
| if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 len = state->end + 1 - state->start; |
| bool do_list = !btrfs_is_free_space_inode(root, inode); |
| |
| if (*bits & EXTENT_FIRST_DELALLOC) { |
| *bits &= ~EXTENT_FIRST_DELALLOC; |
| } else { |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->outstanding_extents++; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| spin_lock(&root->fs_info->delalloc_lock); |
| BTRFS_I(inode)->delalloc_bytes += len; |
| root->fs_info->delalloc_bytes += len; |
| if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) { |
| list_add_tail(&BTRFS_I(inode)->delalloc_inodes, |
| &root->fs_info->delalloc_inodes); |
| } |
| spin_unlock(&root->fs_info->delalloc_lock); |
| } |
| } |
| |
| /* |
| * extent_io.c clear_bit_hook, see set_bit_hook for why |
| */ |
| static void btrfs_clear_bit_hook(struct inode *inode, |
| struct extent_state *state, int *bits) |
| { |
| /* |
| * set_bit and clear bit hooks normally require _irqsave/restore |
| * but in this case, we are only testing for the DELALLOC |
| * bit, which is only set or cleared with irqs on |
| */ |
| if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 len = state->end + 1 - state->start; |
| bool do_list = !btrfs_is_free_space_inode(root, inode); |
| |
| if (*bits & EXTENT_FIRST_DELALLOC) { |
| *bits &= ~EXTENT_FIRST_DELALLOC; |
| } else if (!(*bits & EXTENT_DO_ACCOUNTING)) { |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->outstanding_extents--; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| if (*bits & EXTENT_DO_ACCOUNTING) |
| btrfs_delalloc_release_metadata(inode, len); |
| |
| if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID |
| && do_list) |
| btrfs_free_reserved_data_space(inode, len); |
| |
| spin_lock(&root->fs_info->delalloc_lock); |
| root->fs_info->delalloc_bytes -= len; |
| BTRFS_I(inode)->delalloc_bytes -= len; |
| |
| if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 && |
| !list_empty(&BTRFS_I(inode)->delalloc_inodes)) { |
| list_del_init(&BTRFS_I(inode)->delalloc_inodes); |
| } |
| spin_unlock(&root->fs_info->delalloc_lock); |
| } |
| } |
| |
| /* |
| * extent_io.c merge_bio_hook, this must check the chunk tree to make sure |
| * we don't create bios that span stripes or chunks |
| */ |
| int btrfs_merge_bio_hook(struct page *page, unsigned long offset, |
| size_t size, struct bio *bio, |
| unsigned long bio_flags) |
| { |
| struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; |
| struct btrfs_mapping_tree *map_tree; |
| u64 logical = (u64)bio->bi_sector << 9; |
| u64 length = 0; |
| u64 map_length; |
| int ret; |
| |
| if (bio_flags & EXTENT_BIO_COMPRESSED) |
| return 0; |
| |
| length = bio->bi_size; |
| map_tree = &root->fs_info->mapping_tree; |
| map_length = length; |
| ret = btrfs_map_block(map_tree, READ, logical, |
| &map_length, NULL, 0); |
| /* Will always return 0 or 1 with map_multi == NULL */ |
| BUG_ON(ret < 0); |
| if (map_length < length + size) |
| return 1; |
| return 0; |
| } |
| |
| /* |
| * in order to insert checksums into the metadata in large chunks, |
| * we wait until bio submission time. All the pages in the bio are |
| * checksummed and sums are attached onto the ordered extent record. |
| * |
| * At IO completion time the cums attached on the ordered extent record |
| * are inserted into the btree |
| */ |
| static int __btrfs_submit_bio_start(struct inode *inode, int rw, |
| struct bio *bio, int mirror_num, |
| unsigned long bio_flags, |
| u64 bio_offset) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int ret = 0; |
| |
| ret = btrfs_csum_one_bio(root, inode, bio, 0, 0); |
| BUG_ON(ret); /* -ENOMEM */ |
| return 0; |
| } |
| |
| /* |
| * in order to insert checksums into the metadata in large chunks, |
| * we wait until bio submission time. All the pages in the bio are |
| * checksummed and sums are attached onto the ordered extent record. |
| * |
| * At IO completion time the cums attached on the ordered extent record |
| * are inserted into the btree |
| */ |
| static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio, |
| int mirror_num, unsigned long bio_flags, |
| u64 bio_offset) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| return btrfs_map_bio(root, rw, bio, mirror_num, 1); |
| } |
| |
| /* |
| * extent_io.c submission hook. This does the right thing for csum calculation |
| * on write, or reading the csums from the tree before a read |
| */ |
| static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, |
| int mirror_num, unsigned long bio_flags, |
| u64 bio_offset) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int ret = 0; |
| int skip_sum; |
| int metadata = 0; |
| |
| skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; |
| |
| if (btrfs_is_free_space_inode(root, inode)) |
| metadata = 2; |
| |
| ret = btrfs_bio_wq_end_io(root->fs_info, bio, metadata); |
| if (ret) |
| return ret; |
| |
| if (!(rw & REQ_WRITE)) { |
| if (bio_flags & EXTENT_BIO_COMPRESSED) { |
| return btrfs_submit_compressed_read(inode, bio, |
| mirror_num, bio_flags); |
| } else if (!skip_sum) { |
| ret = btrfs_lookup_bio_sums(root, inode, bio, NULL); |
| if (ret) |
| return ret; |
| } |
| goto mapit; |
| } else if (!skip_sum) { |
| /* csum items have already been cloned */ |
| if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) |
| goto mapit; |
| /* we're doing a write, do the async checksumming */ |
| return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, |
| inode, rw, bio, mirror_num, |
| bio_flags, bio_offset, |
| __btrfs_submit_bio_start, |
| __btrfs_submit_bio_done); |
| } |
| |
| mapit: |
| return btrfs_map_bio(root, rw, bio, mirror_num, 0); |
| } |
| |
| /* |
| * given a list of ordered sums record them in the inode. This happens |
| * at IO completion time based on sums calculated at bio submission time. |
| */ |
| static noinline int add_pending_csums(struct btrfs_trans_handle *trans, |
| struct inode *inode, u64 file_offset, |
| struct list_head *list) |
| { |
| struct btrfs_ordered_sum *sum; |
| |
| list_for_each_entry(sum, list, list) { |
| btrfs_csum_file_blocks(trans, |
| BTRFS_I(inode)->root->fs_info->csum_root, sum); |
| } |
| return 0; |
| } |
| |
| int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, |
| struct extent_state **cached_state) |
| { |
| if ((end & (PAGE_CACHE_SIZE - 1)) == 0) |
| WARN_ON(1); |
| return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, |
| cached_state, GFP_NOFS); |
| } |
| |
| /* see btrfs_writepage_start_hook for details on why this is required */ |
| struct btrfs_writepage_fixup { |
| struct page *page; |
| struct btrfs_work work; |
| }; |
| |
| static void btrfs_writepage_fixup_worker(struct btrfs_work *work) |
| { |
| struct btrfs_writepage_fixup *fixup; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| struct page *page; |
| struct inode *inode; |
| u64 page_start; |
| u64 page_end; |
| int ret; |
| |
| fixup = container_of(work, struct btrfs_writepage_fixup, work); |
| page = fixup->page; |
| again: |
| lock_page(page); |
| if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { |
| ClearPageChecked(page); |
| goto out_page; |
| } |
| |
| inode = page->mapping->host; |
| page_start = page_offset(page); |
| page_end = page_offset(page) + PAGE_CACHE_SIZE - 1; |
| |
| lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0, |
| &cached_state); |
| |
| /* already ordered? We're done */ |
| if (PagePrivate2(page)) |
| goto out; |
| |
| ordered = btrfs_lookup_ordered_extent(inode, page_start); |
| if (ordered) { |
| unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, |
| page_end, &cached_state, GFP_NOFS); |
| unlock_page(page); |
| btrfs_start_ordered_extent(inode, ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| goto again; |
| } |
| |
| ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); |
| if (ret) { |
| mapping_set_error(page->mapping, ret); |
| end_extent_writepage(page, ret, page_start, page_end); |
| ClearPageChecked(page); |
| goto out; |
| } |
| |
| btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state); |
| ClearPageChecked(page); |
| set_page_dirty(page); |
| out: |
| unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, |
| &cached_state, GFP_NOFS); |
| out_page: |
| unlock_page(page); |
| page_cache_release(page); |
| kfree(fixup); |
| } |
| |
| /* |
| * There are a few paths in the higher layers of the kernel that directly |
| * set the page dirty bit without asking the filesystem if it is a |
| * good idea. This causes problems because we want to make sure COW |
| * properly happens and the data=ordered rules are followed. |
| * |
| * In our case any range that doesn't have the ORDERED bit set |
| * hasn't been properly setup for IO. We kick off an async process |
| * to fix it up. The async helper will wait for ordered extents, set |
| * the delalloc bit and make it safe to write the page. |
| */ |
| static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) |
| { |
| struct inode *inode = page->mapping->host; |
| struct btrfs_writepage_fixup *fixup; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| |
| /* this page is properly in the ordered list */ |
| if (TestClearPagePrivate2(page)) |
| return 0; |
| |
| if (PageChecked(page)) |
| return -EAGAIN; |
| |
| fixup = kzalloc(sizeof(*fixup), GFP_NOFS); |
| if (!fixup) |
| return -EAGAIN; |
| |
| SetPageChecked(page); |
| page_cache_get(page); |
| fixup->work.func = btrfs_writepage_fixup_worker; |
| fixup->page = page; |
| btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work); |
| return -EBUSY; |
| } |
| |
| static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, |
| struct inode *inode, u64 file_pos, |
| u64 disk_bytenr, u64 disk_num_bytes, |
| u64 num_bytes, u64 ram_bytes, |
| u8 compression, u8 encryption, |
| u16 other_encoding, int extent_type) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_file_extent_item *fi; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_key ins; |
| u64 hint; |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| path->leave_spinning = 1; |
| |
| /* |
| * we may be replacing one extent in the tree with another. |
| * The new extent is pinned in the extent map, and we don't want |
| * to drop it from the cache until it is completely in the btree. |
| * |
| * So, tell btrfs_drop_extents to leave this extent in the cache. |
| * the caller is expected to unpin it and allow it to be merged |
| * with the others. |
| */ |
| ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes, |
| &hint, 0); |
| if (ret) |
| goto out; |
| |
| ins.objectid = btrfs_ino(inode); |
| ins.offset = file_pos; |
| ins.type = BTRFS_EXTENT_DATA_KEY; |
| ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi)); |
| if (ret) |
| goto out; |
| leaf = path->nodes[0]; |
| fi = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| btrfs_set_file_extent_generation(leaf, fi, trans->transid); |
| btrfs_set_file_extent_type(leaf, fi, extent_type); |
| btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); |
| btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); |
| btrfs_set_file_extent_offset(leaf, fi, 0); |
| btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); |
| btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); |
| btrfs_set_file_extent_compression(leaf, fi, compression); |
| btrfs_set_file_extent_encryption(leaf, fi, encryption); |
| btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); |
| |
| btrfs_unlock_up_safe(path, 1); |
| btrfs_set_lock_blocking(leaf); |
| |
| btrfs_mark_buffer_dirty(leaf); |
| |
| inode_add_bytes(inode, num_bytes); |
| |
| ins.objectid = disk_bytenr; |
| ins.offset = disk_num_bytes; |
| ins.type = BTRFS_EXTENT_ITEM_KEY; |
| ret = btrfs_alloc_reserved_file_extent(trans, root, |
| root->root_key.objectid, |
| btrfs_ino(inode), file_pos, &ins); |
| out: |
| btrfs_free_path(path); |
| |
| return ret; |
| } |
| |
| /* |
| * helper function for btrfs_finish_ordered_io, this |
| * just reads in some of the csum leaves to prime them into ram |
| * before we start the transaction. It limits the amount of btree |
| * reads required while inside the transaction. |
| */ |
| /* as ordered data IO finishes, this gets called so we can finish |
| * an ordered extent if the range of bytes in the file it covers are |
| * fully written. |
| */ |
| static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans = NULL; |
| struct btrfs_ordered_extent *ordered_extent = NULL; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct extent_state *cached_state = NULL; |
| int compress_type = 0; |
| int ret; |
| bool nolock; |
| |
| ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, |
| end - start + 1); |
| if (!ret) |
| return 0; |
| BUG_ON(!ordered_extent); /* Logic error */ |
| |
| nolock = btrfs_is_free_space_inode(root, inode); |
| |
| if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { |
| BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ |
| ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); |
| if (!ret) { |
| if (nolock) |
| trans = btrfs_join_transaction_nolock(root); |
| else |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| ret = btrfs_update_inode_fallback(trans, root, inode); |
| if (ret) /* -ENOMEM or corruption */ |
| btrfs_abort_transaction(trans, root, ret); |
| } |
| goto out; |
| } |
| |
| lock_extent_bits(io_tree, ordered_extent->file_offset, |
| ordered_extent->file_offset + ordered_extent->len - 1, |
| 0, &cached_state); |
| |
| if (nolock) |
| trans = btrfs_join_transaction_nolock(root); |
| else |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| trans = NULL; |
| goto out_unlock; |
| } |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) |
| compress_type = ordered_extent->compress_type; |
| if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { |
| BUG_ON(compress_type); |
| ret = btrfs_mark_extent_written(trans, inode, |
| ordered_extent->file_offset, |
| ordered_extent->file_offset + |
| ordered_extent->len); |
| } else { |
| BUG_ON(root == root->fs_info->tree_root); |
| ret = insert_reserved_file_extent(trans, inode, |
| ordered_extent->file_offset, |
| ordered_extent->start, |
| ordered_extent->disk_len, |
| ordered_extent->len, |
| ordered_extent->len, |
| compress_type, 0, 0, |
| BTRFS_FILE_EXTENT_REG); |
| unpin_extent_cache(&BTRFS_I(inode)->extent_tree, |
| ordered_extent->file_offset, |
| ordered_extent->len); |
| } |
| unlock_extent_cached(io_tree, ordered_extent->file_offset, |
| ordered_extent->file_offset + |
| ordered_extent->len - 1, &cached_state, GFP_NOFS); |
| if (ret < 0) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| |
| add_pending_csums(trans, inode, ordered_extent->file_offset, |
| &ordered_extent->list); |
| |
| ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); |
| if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { |
| ret = btrfs_update_inode_fallback(trans, root, inode); |
| if (ret) { /* -ENOMEM or corruption */ |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| } |
| ret = 0; |
| out: |
| if (root != root->fs_info->tree_root) |
| btrfs_delalloc_release_metadata(inode, ordered_extent->len); |
| if (trans) { |
| if (nolock) |
| btrfs_end_transaction_nolock(trans, root); |
| else |
| btrfs_end_transaction(trans, root); |
| } |
| |
| /* once for us */ |
| btrfs_put_ordered_extent(ordered_extent); |
| /* once for the tree */ |
| btrfs_put_ordered_extent(ordered_extent); |
| |
| return 0; |
| out_unlock: |
| unlock_extent_cached(io_tree, ordered_extent->file_offset, |
| ordered_extent->file_offset + |
| ordered_extent->len - 1, &cached_state, GFP_NOFS); |
| goto out; |
| } |
| |
| static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, |
| struct extent_state *state, int uptodate) |
| { |
| trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); |
| |
| ClearPagePrivate2(page); |
| return btrfs_finish_ordered_io(page->mapping->host, start, end); |
| } |
| |
| /* |
| * when reads are done, we need to check csums to verify the data is correct |
| * if there's a match, we allow the bio to finish. If not, the code in |
| * extent_io.c will try to find good copies for us. |
| */ |
| static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, |
| struct extent_state *state, int mirror) |
| { |
| size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT); |
| struct inode *inode = page->mapping->host; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| char *kaddr; |
| u64 private = ~(u32)0; |
| int ret; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u32 csum = ~(u32)0; |
| |
| if (PageChecked(page)) { |
| ClearPageChecked(page); |
| goto good; |
| } |
| |
| if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) |
| goto good; |
| |
| if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && |
| test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { |
| clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM, |
| GFP_NOFS); |
| return 0; |
| } |
| |
| if (state && state->start == start) { |
| private = state->private; |
| ret = 0; |
| } else { |
| ret = get_state_private(io_tree, start, &private); |
| } |
| kaddr = kmap_atomic(page); |
| if (ret) |
| goto zeroit; |
| |
| csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1); |
| btrfs_csum_final(csum, (char *)&csum); |
| if (csum != private) |
| goto zeroit; |
| |
| kunmap_atomic(kaddr); |
| good: |
| return 0; |
| |
| zeroit: |
| printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u " |
| "private %llu\n", |
| (unsigned long long)btrfs_ino(page->mapping->host), |
| (unsigned long long)start, csum, |
| (unsigned long long)private); |
| memset(kaddr + offset, 1, end - start + 1); |
| flush_dcache_page(page); |
| kunmap_atomic(kaddr); |
| if (private == 0) |
| return 0; |
| return -EIO; |
| } |
| |
| struct delayed_iput { |
| struct list_head list; |
| struct inode *inode; |
| }; |
| |
| /* JDM: If this is fs-wide, why can't we add a pointer to |
| * btrfs_inode instead and avoid the allocation? */ |
| void btrfs_add_delayed_iput(struct inode *inode) |
| { |
| struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; |
| struct delayed_iput *delayed; |
| |
| if (atomic_add_unless(&inode->i_count, -1, 1)) |
| return; |
| |
| delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL); |
| delayed->inode = inode; |
| |
| spin_lock(&fs_info->delayed_iput_lock); |
| list_add_tail(&delayed->list, &fs_info->delayed_iputs); |
| spin_unlock(&fs_info->delayed_iput_lock); |
| } |
| |
| void btrfs_run_delayed_iputs(struct btrfs_root *root) |
| { |
| LIST_HEAD(list); |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct delayed_iput *delayed; |
| int empty; |
| |
| spin_lock(&fs_info->delayed_iput_lock); |
| empty = list_empty(&fs_info->delayed_iputs); |
| spin_unlock(&fs_info->delayed_iput_lock); |
| if (empty) |
| return; |
| |
| down_read(&root->fs_info->cleanup_work_sem); |
| spin_lock(&fs_info->delayed_iput_lock); |
| list_splice_init(&fs_info->delayed_iputs, &list); |
| spin_unlock(&fs_info->delayed_iput_lock); |
| |
| while (!list_empty(&list)) { |
| delayed = list_entry(list.next, struct delayed_iput, list); |
| list_del(&delayed->list); |
| iput(delayed->inode); |
| kfree(delayed); |
| } |
| up_read(&root->fs_info->cleanup_work_sem); |
| } |
| |
| enum btrfs_orphan_cleanup_state { |
| ORPHAN_CLEANUP_STARTED = 1, |
| ORPHAN_CLEANUP_DONE = 2, |
| }; |
| |
| /* |
| * This is called in transaction commit time. If there are no orphan |
| * files in the subvolume, it removes orphan item and frees block_rsv |
| * structure. |
| */ |
| void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root) |
| { |
| struct btrfs_block_rsv *block_rsv; |
| int ret; |
| |
| if (!list_empty(&root->orphan_list) || |
| root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) |
| return; |
| |
| spin_lock(&root->orphan_lock); |
| if (!list_empty(&root->orphan_list)) { |
| spin_unlock(&root->orphan_lock); |
| return; |
| } |
| |
| if (root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) { |
| spin_unlock(&root->orphan_lock); |
| return; |
| } |
| |
| block_rsv = root->orphan_block_rsv; |
| root->orphan_block_rsv = NULL; |
| spin_unlock(&root->orphan_lock); |
| |
| if (root->orphan_item_inserted && |
| btrfs_root_refs(&root->root_item) > 0) { |
| ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root, |
| root->root_key.objectid); |
| BUG_ON(ret); |
| root->orphan_item_inserted = 0; |
| } |
| |
| if (block_rsv) { |
| WARN_ON(block_rsv->size > 0); |
| btrfs_free_block_rsv(root, block_rsv); |
| } |
| } |
| |
| /* |
| * This creates an orphan entry for the given inode in case something goes |
| * wrong in the middle of an unlink/truncate. |
| * |
| * NOTE: caller of this function should reserve 5 units of metadata for |
| * this function. |
| */ |
| int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_block_rsv *block_rsv = NULL; |
| int reserve = 0; |
| int insert = 0; |
| int ret; |
| |
| if (!root->orphan_block_rsv) { |
| block_rsv = btrfs_alloc_block_rsv(root); |
| if (!block_rsv) |
| return -ENOMEM; |
| } |
| |
| spin_lock(&root->orphan_lock); |
| if (!root->orphan_block_rsv) { |
| root->orphan_block_rsv = block_rsv; |
| } else if (block_rsv) { |
| btrfs_free_block_rsv(root, block_rsv); |
| block_rsv = NULL; |
| } |
| |
| if (list_empty(&BTRFS_I(inode)->i_orphan)) { |
| list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); |
| #if 0 |
| /* |
| * For proper ENOSPC handling, we should do orphan |
| * cleanup when mounting. But this introduces backward |
| * compatibility issue. |
| */ |
| if (!xchg(&root->orphan_item_inserted, 1)) |
| insert = 2; |
| else |
| insert = 1; |
| #endif |
| insert = 1; |
| } |
| |
| if (!BTRFS_I(inode)->orphan_meta_reserved) { |
| BTRFS_I(inode)->orphan_meta_reserved = 1; |
| reserve = 1; |
| } |
| spin_unlock(&root->orphan_lock); |
| |
| /* grab metadata reservation from transaction handle */ |
| if (reserve) { |
| ret = btrfs_orphan_reserve_metadata(trans, inode); |
| BUG_ON(ret); /* -ENOSPC in reservation; Logic error? JDM */ |
| } |
| |
| /* insert an orphan item to track this unlinked/truncated file */ |
| if (insert >= 1) { |
| ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode)); |
| if (ret && ret != -EEXIST) { |
| btrfs_abort_transaction(trans, root, ret); |
| return ret; |
| } |
| ret = 0; |
| } |
| |
| /* insert an orphan item to track subvolume contains orphan files */ |
| if (insert >= 2) { |
| ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, |
| root->root_key.objectid); |
| if (ret && ret != -EEXIST) { |
| btrfs_abort_transaction(trans, root, ret); |
| return ret; |
| } |
| } |
| return 0; |
| } |
| |
| /* |
| * We have done the truncate/delete so we can go ahead and remove the orphan |
| * item for this particular inode. |
| */ |
| int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int delete_item = 0; |
| int release_rsv = 0; |
| int ret = 0; |
| |
| spin_lock(&root->orphan_lock); |
| if (!list_empty(&BTRFS_I(inode)->i_orphan)) { |
| list_del_init(&BTRFS_I(inode)->i_orphan); |
| delete_item = 1; |
| } |
| |
| if (BTRFS_I(inode)->orphan_meta_reserved) { |
| BTRFS_I(inode)->orphan_meta_reserved = 0; |
| release_rsv = 1; |
| } |
| spin_unlock(&root->orphan_lock); |
| |
| if (trans && delete_item) { |
| ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode)); |
| BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */ |
| } |
| |
| if (release_rsv) |
| btrfs_orphan_release_metadata(inode); |
| |
| return 0; |
| } |
| |
| /* |
| * this cleans up any orphans that may be left on the list from the last use |
| * of this root. |
| */ |
| int btrfs_orphan_cleanup(struct btrfs_root *root) |
| { |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_key key, found_key; |
| struct btrfs_trans_handle *trans; |
| struct inode *inode; |
| u64 last_objectid = 0; |
| int ret = 0, nr_unlink = 0, nr_truncate = 0; |
| |
| if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) |
| return 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| path->reada = -1; |
| |
| key.objectid = BTRFS_ORPHAN_OBJECTID; |
| btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY); |
| key.offset = (u64)-1; |
| |
| while (1) { |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| |
| /* |
| * if ret == 0 means we found what we were searching for, which |
| * is weird, but possible, so only screw with path if we didn't |
| * find the key and see if we have stuff that matches |
| */ |
| if (ret > 0) { |
| ret = 0; |
| if (path->slots[0] == 0) |
| break; |
| path->slots[0]--; |
| } |
| |
| /* pull out the item */ |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| |
| /* make sure the item matches what we want */ |
| if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) |
| break; |
| if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY) |
| break; |
| |
| /* release the path since we're done with it */ |
| btrfs_release_path(path); |
| |
| /* |
| * this is where we are basically btrfs_lookup, without the |
| * crossing root thing. we store the inode number in the |
| * offset of the orphan item. |
| */ |
| |
| if (found_key.offset == last_objectid) { |
| printk(KERN_ERR "btrfs: Error removing orphan entry, " |
| "stopping orphan cleanup\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| last_objectid = found_key.offset; |
| |
| found_key.objectid = found_key.offset; |
| found_key.type = BTRFS_INODE_ITEM_KEY; |
| found_key.offset = 0; |
| inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL); |
| ret = PTR_RET(inode); |
| if (ret && ret != -ESTALE) |
| goto out; |
| |
| if (ret == -ESTALE && root == root->fs_info->tree_root) { |
| struct btrfs_root *dead_root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| int is_dead_root = 0; |
| |
| /* |
| * this is an orphan in the tree root. Currently these |
| * could come from 2 sources: |
| * a) a snapshot deletion in progress |
| * b) a free space cache inode |
| * We need to distinguish those two, as the snapshot |
| * orphan must not get deleted. |
| * find_dead_roots already ran before us, so if this |
| * is a snapshot deletion, we should find the root |
| * in the dead_roots list |
| */ |
| spin_lock(&fs_info->trans_lock); |
| list_for_each_entry(dead_root, &fs_info->dead_roots, |
| root_list) { |
| if (dead_root->root_key.objectid == |
| found_key.objectid) { |
| is_dead_root = 1; |
| break; |
| } |
| } |
| spin_unlock(&fs_info->trans_lock); |
| if (is_dead_root) { |
| /* prevent this orphan from being found again */ |
| key.offset = found_key.objectid - 1; |
| continue; |
| } |
| } |
| /* |
| * Inode is already gone but the orphan item is still there, |
| * kill the orphan item. |
| */ |
| if (ret == -ESTALE) { |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out; |
| } |
| ret = btrfs_del_orphan_item(trans, root, |
| found_key.objectid); |
| BUG_ON(ret); /* -ENOMEM or corruption (JDM: Recheck) */ |
| btrfs_end_transaction(trans, root); |
| continue; |
| } |
| |
| /* |
| * add this inode to the orphan list so btrfs_orphan_del does |
| * the proper thing when we hit it |
| */ |
| spin_lock(&root->orphan_lock); |
| list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); |
| spin_unlock(&root->orphan_lock); |
| |
| /* if we have links, this was a truncate, lets do that */ |
| if (inode->i_nlink) { |
| if (!S_ISREG(inode->i_mode)) { |
| WARN_ON(1); |
| iput(inode); |
| continue; |
| } |
| nr_truncate++; |
| ret = btrfs_truncate(inode); |
| } else { |
| nr_unlink++; |
| } |
| |
| /* this will do delete_inode and everything for us */ |
| iput(inode); |
| if (ret) |
| goto out; |
| } |
| /* release the path since we're done with it */ |
| btrfs_release_path(path); |
| |
| root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; |
| |
| if (root->orphan_block_rsv) |
| btrfs_block_rsv_release(root, root->orphan_block_rsv, |
| (u64)-1); |
| |
| if (root->orphan_block_rsv || root->orphan_item_inserted) { |
| trans = btrfs_join_transaction(root); |
| if (!IS_ERR(trans)) |
| btrfs_end_transaction(trans, root); |
| } |
| |
| if (nr_unlink) |
| printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink); |
| if (nr_truncate) |
| printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate); |
| |
| out: |
| if (ret) |
| printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret); |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * very simple check to peek ahead in the leaf looking for xattrs. If we |
| * don't find any xattrs, we know there can't be any acls. |
| * |
| * slot is the slot the inode is in, objectid is the objectid of the inode |
| */ |
| static noinline int acls_after_inode_item(struct extent_buffer *leaf, |
| int slot, u64 objectid) |
| { |
| u32 nritems = btrfs_header_nritems(leaf); |
| struct btrfs_key found_key; |
| int scanned = 0; |
| |
| slot++; |
| while (slot < nritems) { |
| btrfs_item_key_to_cpu(leaf, &found_key, slot); |
| |
| /* we found a different objectid, there must not be acls */ |
| if (found_key.objectid != objectid) |
| return 0; |
| |
| /* we found an xattr, assume we've got an acl */ |
| if (found_key.type == BTRFS_XATTR_ITEM_KEY) |
| return 1; |
| |
| /* |
| * we found a key greater than an xattr key, there can't |
| * be any acls later on |
| */ |
| if (found_key.type > BTRFS_XATTR_ITEM_KEY) |
| return 0; |
| |
| slot++; |
| scanned++; |
| |
| /* |
| * it goes inode, inode backrefs, xattrs, extents, |
| * so if there are a ton of hard links to an inode there can |
| * be a lot of backrefs. Don't waste time searching too hard, |
| * this is just an optimization |
| */ |
| if (scanned >= 8) |
| break; |
| } |
| /* we hit the end of the leaf before we found an xattr or |
| * something larger than an xattr. We have to assume the inode |
| * has acls |
| */ |
| return 1; |
| } |
| |
| /* |
| * read an inode from the btree into the in-memory inode |
| */ |
| static void btrfs_read_locked_inode(struct inode *inode) |
| { |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_inode_item *inode_item; |
| struct btrfs_timespec *tspec; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_key location; |
| int maybe_acls; |
| u32 rdev; |
| int ret; |
| bool filled = false; |
| |
| ret = btrfs_fill_inode(inode, &rdev); |
| if (!ret) |
| filled = true; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| goto make_bad; |
| |
| path->leave_spinning = 1; |
| memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); |
| |
| ret = btrfs_lookup_inode(NULL, root, path, &location, 0); |
| if (ret) |
| goto make_bad; |
| |
| leaf = path->nodes[0]; |
| |
| if (filled) |
| goto cache_acl; |
| |
| inode_item = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_inode_item); |
| inode->i_mode = btrfs_inode_mode(leaf, inode_item); |
| set_nlink(inode, btrfs_inode_nlink(leaf, inode_item)); |
| inode->i_uid = btrfs_inode_uid(leaf, inode_item); |
| inode->i_gid = btrfs_inode_gid(leaf, inode_item); |
| btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item)); |
| |
| tspec = btrfs_inode_atime(inode_item); |
| inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec); |
| inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); |
| |
| tspec = btrfs_inode_mtime(inode_item); |
| inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec); |
| inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); |
| |
| tspec = btrfs_inode_ctime(inode_item); |
| inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec); |
| inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec); |
| |
| inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item)); |
| BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item); |
| BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item); |
| inode->i_generation = BTRFS_I(inode)->generation; |
| inode->i_rdev = 0; |
| rdev = btrfs_inode_rdev(leaf, inode_item); |
| |
| BTRFS_I(inode)->index_cnt = (u64)-1; |
| BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item); |
| cache_acl: |
| /* |
| * try to precache a NULL acl entry for files that don't have |
| * any xattrs or acls |
| */ |
| maybe_acls = acls_after_inode_item(leaf, path->slots[0], |
| btrfs_ino(inode)); |
| if (!maybe_acls) |
| cache_no_acl(inode); |
| |
| btrfs_free_path(path); |
| |
| switch (inode->i_mode & S_IFMT) { |
| case S_IFREG: |
| inode->i_mapping->a_ops = &btrfs_aops; |
| inode->i_mapping->backing_dev_info = &root->fs_info->bdi; |
| BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; |
| inode->i_fop = &btrfs_file_operations; |
| inode->i_op = &btrfs_file_inode_operations; |
| break; |
| case S_IFDIR: |
| inode->i_fop = &btrfs_dir_file_operations; |
| if (root == root->fs_info->tree_root) |
| inode->i_op = &btrfs_dir_ro_inode_operations; |
| else |
| inode->i_op = &btrfs_dir_inode_operations; |
| break; |
| case S_IFLNK: |
| inode->i_op = &btrfs_symlink_inode_operations; |
| inode->i_mapping->a_ops = &btrfs_symlink_aops; |
| inode->i_mapping->backing_dev_info = &root->fs_info->bdi; |
| break; |
| default: |
| inode->i_op = &btrfs_special_inode_operations; |
| init_special_inode(inode, inode->i_mode, rdev); |
| break; |
| } |
| |
| btrfs_update_iflags(inode); |
| return; |
| |
| make_bad: |
| btrfs_free_path(path); |
| make_bad_inode(inode); |
| } |
| |
| /* |
| * given a leaf and an inode, copy the inode fields into the leaf |
| */ |
| static void fill_inode_item(struct btrfs_trans_handle *trans, |
| struct extent_buffer *leaf, |
| struct btrfs_inode_item *item, |
| struct inode *inode) |
| { |
| btrfs_set_inode_uid(leaf, item, inode->i_uid); |
| btrfs_set_inode_gid(leaf, item, inode->i_gid); |
| btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size); |
| btrfs_set_inode_mode(leaf, item, inode->i_mode); |
| btrfs_set_inode_nlink(leaf, item, inode->i_nlink); |
| |
| btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item), |
| inode->i_atime.tv_sec); |
| btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item), |
| inode->i_atime.tv_nsec); |
| |
| btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item), |
| inode->i_mtime.tv_sec); |
| btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item), |
| inode->i_mtime.tv_nsec); |
| |
| btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item), |
| inode->i_ctime.tv_sec); |
| btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item), |
| inode->i_ctime.tv_nsec); |
| |
| btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode)); |
| btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation); |
| btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence); |
| btrfs_set_inode_transid(leaf, item, trans->transid); |
| btrfs_set_inode_rdev(leaf, item, inode->i_rdev); |
| btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags); |
| btrfs_set_inode_block_group(leaf, item, 0); |
| } |
| |
| /* |
| * copy everything in the in-memory inode into the btree. |
| */ |
| static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode) |
| { |
| struct btrfs_inode_item *inode_item; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| path->leave_spinning = 1; |
| ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location, |
| 1); |
| if (ret) { |
| if (ret > 0) |
| ret = -ENOENT; |
| goto failed; |
| } |
| |
| btrfs_unlock_up_safe(path, 1); |
| leaf = path->nodes[0]; |
| inode_item = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_inode_item); |
| |
| fill_inode_item(trans, leaf, inode_item, inode); |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_set_inode_last_trans(trans, inode); |
| ret = 0; |
| failed: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * copy everything in the in-memory inode into the btree. |
| */ |
| noinline int btrfs_update_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode) |
| { |
| int ret; |
| |
| /* |
| * If the inode is a free space inode, we can deadlock during commit |
| * if we put it into the delayed code. |
| * |
| * The data relocation inode should also be directly updated |
| * without delay |
| */ |
| if (!btrfs_is_free_space_inode(root, inode) |
| && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) { |
| ret = btrfs_delayed_update_inode(trans, root, inode); |
| if (!ret) |
| btrfs_set_inode_last_trans(trans, inode); |
| return ret; |
| } |
| |
| return btrfs_update_inode_item(trans, root, inode); |
| } |
| |
| static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode) |
| { |
| int ret; |
| |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret == -ENOSPC) |
| return btrfs_update_inode_item(trans, root, inode); |
| return ret; |
| } |
| |
| /* |
| * unlink helper that gets used here in inode.c and in the tree logging |
| * recovery code. It remove a link in a directory with a given name, and |
| * also drops the back refs in the inode to the directory |
| */ |
| static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *dir, struct inode *inode, |
| const char *name, int name_len) |
| { |
| struct btrfs_path *path; |
| int ret = 0; |
| struct extent_buffer *leaf; |
| struct btrfs_dir_item *di; |
| struct btrfs_key key; |
| u64 index; |
| u64 ino = btrfs_ino(inode); |
| u64 dir_ino = btrfs_ino(dir); |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| path->leave_spinning = 1; |
| di = btrfs_lookup_dir_item(trans, root, path, dir_ino, |
| name, name_len, -1); |
| if (IS_ERR(di)) { |
| ret = PTR_ERR(di); |
| goto err; |
| } |
| if (!di) { |
| ret = -ENOENT; |
| goto err; |
| } |
| leaf = path->nodes[0]; |
| btrfs_dir_item_key_to_cpu(leaf, di, &key); |
| ret = btrfs_delete_one_dir_name(trans, root, path, di); |
| if (ret) |
| goto err; |
| btrfs_release_path(path); |
| |
| ret = btrfs_del_inode_ref(trans, root, name, name_len, ino, |
| dir_ino, &index); |
| if (ret) { |
| printk(KERN_INFO "btrfs failed to delete reference to %.*s, " |
| "inode %llu parent %llu\n", name_len, name, |
| (unsigned long long)ino, (unsigned long long)dir_ino); |
| btrfs_abort_transaction(trans, root, ret); |
| goto err; |
| } |
| |
| ret = btrfs_delete_delayed_dir_index(trans, root, dir, index); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto err; |
| } |
| |
| ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, |
| inode, dir_ino); |
| if (ret != 0 && ret != -ENOENT) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto err; |
| } |
| |
| ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, |
| dir, index); |
| if (ret == -ENOENT) |
| ret = 0; |
| err: |
| btrfs_free_path(path); |
| if (ret) |
| goto out; |
| |
| btrfs_i_size_write(dir, dir->i_size - name_len * 2); |
| inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME; |
| btrfs_update_inode(trans, root, dir); |
| out: |
| return ret; |
| } |
| |
| int btrfs_unlink_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *dir, struct inode *inode, |
| const char *name, int name_len) |
| { |
| int ret; |
| ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len); |
| if (!ret) { |
| btrfs_drop_nlink(inode); |
| ret = btrfs_update_inode(trans, root, inode); |
| } |
| return ret; |
| } |
| |
| |
| /* helper to check if there is any shared block in the path */ |
| static int check_path_shared(struct btrfs_root *root, |
| struct btrfs_path *path) |
| { |
| struct extent_buffer *eb; |
| int level; |
| u64 refs = 1; |
| |
| for (level = 0; level < BTRFS_MAX_LEVEL; level++) { |
| int ret; |
| |
| if (!path->nodes[level]) |
| break; |
| eb = path->nodes[level]; |
| if (!btrfs_block_can_be_shared(root, eb)) |
| continue; |
| ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len, |
| &refs, NULL); |
| if (refs > 1) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * helper to start transaction for unlink and rmdir. |
| * |
| * unlink and rmdir are special in btrfs, they do not always free space. |
| * so in enospc case, we should make sure they will free space before |
| * allowing them to use the global metadata reservation. |
| */ |
| static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir, |
| struct dentry *dentry) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_path *path; |
| struct btrfs_inode_ref *ref; |
| struct btrfs_dir_item *di; |
| struct inode *inode = dentry->d_inode; |
| u64 index; |
| int check_link = 1; |
| int err = -ENOSPC; |
| int ret; |
| u64 ino = btrfs_ino(inode); |
| u64 dir_ino = btrfs_ino(dir); |
| |
| /* |
| * 1 for the possible orphan item |
| * 1 for the dir item |
| * 1 for the dir index |
| * 1 for the inode ref |
| * 1 for the inode ref in the tree log |
| * 2 for the dir entries in the log |
| * 1 for the inode |
| */ |
| trans = btrfs_start_transaction(root, 8); |
| if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC) |
| return trans; |
| |
| if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) |
| return ERR_PTR(-ENOSPC); |
| |
| /* check if there is someone else holds reference */ |
| if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1) |
| return ERR_PTR(-ENOSPC); |
| |
| if (atomic_read(&inode->i_count) > 2) |
| return ERR_PTR(-ENOSPC); |
| |
| if (xchg(&root->fs_info->enospc_unlink, 1)) |
| return ERR_PTR(-ENOSPC); |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| root->fs_info->enospc_unlink = 0; |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| /* 1 for the orphan item */ |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| btrfs_free_path(path); |
| root->fs_info->enospc_unlink = 0; |
| return trans; |
| } |
| |
| path->skip_locking = 1; |
| path->search_commit_root = 1; |
| |
| ret = btrfs_lookup_inode(trans, root, path, |
| &BTRFS_I(dir)->location, 0); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| if (ret == 0) { |
| if (check_path_shared(root, path)) |
| goto out; |
| } else { |
| check_link = 0; |
| } |
| btrfs_release_path(path); |
| |
| ret = btrfs_lookup_inode(trans, root, path, |
| &BTRFS_I(inode)->location, 0); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| if (ret == 0) { |
| if (check_path_shared(root, path)) |
| goto out; |
| } else { |
| check_link = 0; |
| } |
| btrfs_release_path(path); |
| |
| if (ret == 0 && S_ISREG(inode->i_mode)) { |
| ret = btrfs_lookup_file_extent(trans, root, path, |
| ino, (u64)-1, 0); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| BUG_ON(ret == 0); /* Corruption */ |
| if (check_path_shared(root, path)) |
| goto out; |
| btrfs_release_path(path); |
| } |
| |
| if (!check_link) { |
| err = 0; |
| goto out; |
| } |
| |
| di = btrfs_lookup_dir_item(trans, root, path, dir_ino, |
| dentry->d_name.name, dentry->d_name.len, 0); |
| if (IS_ERR(di)) { |
| err = PTR_ERR(di); |
| goto out; |
| } |
| if (di) { |
| if (check_path_shared(root, path)) |
| goto out; |
| } else { |
| err = 0; |
| goto out; |
| } |
| btrfs_release_path(path); |
| |
| ref = btrfs_lookup_inode_ref(trans, root, path, |
| dentry->d_name.name, dentry->d_name.len, |
| ino, dir_ino, 0); |
| if (IS_ERR(ref)) { |
| err = PTR_ERR(ref); |
| goto out; |
| } |
| BUG_ON(!ref); /* Logic error */ |
| if (check_path_shared(root, path)) |
| goto out; |
| index = btrfs_inode_ref_index(path->nodes[0], ref); |
| btrfs_release_path(path); |
| |
| /* |
| * This is a commit root search, if we can lookup inode item and other |
| * relative items in the commit root, it means the transaction of |
| * dir/file creation has been committed, and the dir index item that we |
| * delay to insert has also been inserted into the commit root. So |
| * we needn't worry about the delayed insertion of the dir index item |
| * here. |
| */ |
| di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index, |
| dentry->d_name.name, dentry->d_name.len, 0); |
| if (IS_ERR(di)) { |
| err = PTR_ERR(di); |
| goto out; |
| } |
| BUG_ON(ret == -ENOENT); |
| if (check_path_shared(root, path)) |
| goto out; |
| |
| err = 0; |
| out: |
| btrfs_free_path(path); |
| /* Migrate the orphan reservation over */ |
| if (!err) |
| err = btrfs_block_rsv_migrate(trans->block_rsv, |
| &root->fs_info->global_block_rsv, |
| trans->bytes_reserved); |
| |
| if (err) { |
| btrfs_end_transaction(trans, root); |
| root->fs_info->enospc_unlink = 0; |
| return ERR_PTR(err); |
| } |
| |
| trans->block_rsv = &root->fs_info->global_block_rsv; |
| return trans; |
| } |
| |
| static void __unlink_end_trans(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root) |
| { |
| if (trans->block_rsv == &root->fs_info->global_block_rsv) { |
| btrfs_block_rsv_release(root, trans->block_rsv, |
| trans->bytes_reserved); |
| trans->block_rsv = &root->fs_info->trans_block_rsv; |
| BUG_ON(!root->fs_info->enospc_unlink); |
| root->fs_info->enospc_unlink = 0; |
| } |
| btrfs_end_transaction(trans, root); |
| } |
| |
| static int btrfs_unlink(struct inode *dir, struct dentry *dentry) |
| { |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_trans_handle *trans; |
| struct inode *inode = dentry->d_inode; |
| int ret; |
| unsigned long nr = 0; |
| |
| trans = __unlink_start_trans(dir, dentry); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0); |
| |
| ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode, |
| dentry->d_name.name, dentry->d_name.len); |
| if (ret) |
| goto out; |
| |
| if (inode->i_nlink == 0) { |
| ret = btrfs_orphan_add(trans, inode); |
| if (ret) |
| goto out; |
| } |
| |
| out: |
| nr = trans->blocks_used; |
| __unlink_end_trans(trans, root); |
| btrfs_btree_balance_dirty(root, nr); |
| return ret; |
| } |
| |
| int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *dir, u64 objectid, |
| const char *name, int name_len) |
| { |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_dir_item *di; |
| struct btrfs_key key; |
| u64 index; |
| int ret; |
| u64 dir_ino = btrfs_ino(dir); |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| di = btrfs_lookup_dir_item(trans, root, path, dir_ino, |
| name, name_len, -1); |
| if (IS_ERR_OR_NULL(di)) { |
| if (!di) |
| ret = -ENOENT; |
| else |
| ret = PTR_ERR(di); |
| goto out; |
| } |
| |
| leaf = path->nodes[0]; |
| btrfs_dir_item_key_to_cpu(leaf, di, &key); |
| WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid); |
| ret = btrfs_delete_one_dir_name(trans, root, path, di); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| btrfs_release_path(path); |
| |
| ret = btrfs_del_root_ref(trans, root->fs_info->tree_root, |
| objectid, root->root_key.objectid, |
| dir_ino, &index, name, name_len); |
| if (ret < 0) { |
| if (ret != -ENOENT) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| di = btrfs_search_dir_index_item(root, path, dir_ino, |
| name, name_len); |
| if (IS_ERR_OR_NULL(di)) { |
| if (!di) |
| ret = -ENOENT; |
| else |
| ret = PTR_ERR(di); |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); |
| btrfs_release_path(path); |
| index = key.offset; |
| } |
| btrfs_release_path(path); |
| |
| ret = btrfs_delete_delayed_dir_index(trans, root, dir, index); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out; |
| } |
| |
| btrfs_i_size_write(dir, dir->i_size - name_len * 2); |
| dir->i_mtime = dir->i_ctime = CURRENT_TIME; |
| ret = btrfs_update_inode(trans, root, dir); |
| if (ret) |
| btrfs_abort_transaction(trans, root, ret); |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static int btrfs_rmdir(struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *inode = dentry->d_inode; |
| int err = 0; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_trans_handle *trans; |
| unsigned long nr = 0; |
| |
| if (inode->i_size > BTRFS_EMPTY_DIR_SIZE || |
| btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID) |
| return -ENOTEMPTY; |
| |
| trans = __unlink_start_trans(dir, dentry); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { |
| err = btrfs_unlink_subvol(trans, root, dir, |
| BTRFS_I(inode)->location.objectid, |
| dentry->d_name.name, |
| dentry->d_name.len); |
| goto out; |
| } |
| |
| err = btrfs_orphan_add(trans, inode); |
| if (err) |
| goto out; |
| |
| /* now the directory is empty */ |
| err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode, |
| dentry->d_name.name, dentry->d_name.len); |
| if (!err) |
| btrfs_i_size_write(inode, 0); |
| out: |
| nr = trans->blocks_used; |
| __unlink_end_trans(trans, root); |
| btrfs_btree_balance_dirty(root, nr); |
| |
| return err; |
| } |
| |
| /* |
| * this can truncate away extent items, csum items and directory items. |
| * It starts at a high offset and removes keys until it can't find |
| * any higher than new_size |
| * |
| * csum items that cross the new i_size are truncated to the new size |
| * as well. |
| * |
| * min_type is the minimum key type to truncate down to. If set to 0, this |
| * will kill all the items on this inode, including the INODE_ITEM_KEY. |
| */ |
| int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *inode, |
| u64 new_size, u32 min_type) |
| { |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_file_extent_item *fi; |
| struct btrfs_key key; |
| struct btrfs_key found_key; |
| u64 extent_start = 0; |
| u64 extent_num_bytes = 0; |
| u64 extent_offset = 0; |
| u64 item_end = 0; |
| u64 mask = root->sectorsize - 1; |
| u32 found_type = (u8)-1; |
| int found_extent; |
| int del_item; |
| int pending_del_nr = 0; |
| int pending_del_slot = 0; |
| int extent_type = -1; |
| int ret; |
| int err = 0; |
| u64 ino = btrfs_ino(inode); |
| |
| BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| path->reada = -1; |
| |
| if (root->ref_cows || root == root->fs_info->tree_root) |
| btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0); |
| |
| /* |
| * This function is also used to drop the items in the log tree before |
| * we relog the inode, so if root != BTRFS_I(inode)->root, it means |
| * it is used to drop the loged items. So we shouldn't kill the delayed |
| * items. |
| */ |
| if (min_type == 0 && root == BTRFS_I(inode)->root) |
| btrfs_kill_delayed_inode_items(inode); |
| |
| key.objectid = ino; |
| key.offset = (u64)-1; |
| key.type = (u8)-1; |
| |
| search_again: |
| path->leave_spinning = 1; |
| ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| |
| if (ret > 0) { |
| /* there are no items in the tree for us to truncate, we're |
| * done |
| */ |
| if (path->slots[0] == 0) |
| goto out; |
| path->slots[0]--; |
| } |
| |
| while (1) { |
| fi = NULL; |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| found_type = btrfs_key_type(&found_key); |
| |
| if (found_key.objectid != ino) |
| break; |
| |
| if (found_type < min_type) |
| break; |
| |
| item_end = found_key.offset; |
| if (found_type == BTRFS_EXTENT_DATA_KEY) { |
| fi = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| extent_type = btrfs_file_extent_type(leaf, fi); |
| if (extent_type != BTRFS_FILE_EXTENT_INLINE) { |
| item_end += |
| btrfs_file_extent_num_bytes(leaf, fi); |
| } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { |
| item_end += btrfs_file_extent_inline_len(leaf, |
| fi); |
| } |
| item_end--; |
| } |
| if (found_type > min_type) { |
| del_item = 1; |
| } else { |
| if (item_end < new_size) |
| break; |
| if (found_key.offset >= new_size) |
| del_item = 1; |
| else |
| del_item = 0; |
| } |
| found_extent = 0; |
| /* FIXME, shrink the extent if the ref count is only 1 */ |
| if (found_type != BTRFS_EXTENT_DATA_KEY) |
| goto delete; |
| |
| if (extent_type != BTRFS_FILE_EXTENT_INLINE) { |
| u64 num_dec; |
| extent_start = btrfs_file_extent_disk_bytenr(leaf, fi); |
| if (!del_item) { |
| u64 orig_num_bytes = |
| btrfs_file_extent_num_bytes(leaf, fi); |
| extent_num_bytes = new_size - |
| found_key.offset + root->sectorsize - 1; |
| extent_num_bytes = extent_num_bytes & |
| ~((u64)root->sectorsize - 1); |
| btrfs_set_file_extent_num_bytes(leaf, fi, |
| extent_num_bytes); |
| num_dec = (orig_num_bytes - |
| extent_num_bytes); |
| if (root->ref_cows && extent_start != 0) |
| inode_sub_bytes(inode, num_dec); |
| btrfs_mark_buffer_dirty(leaf); |
| } else { |
| extent_num_bytes = |
| btrfs_file_extent_disk_num_bytes(leaf, |
| fi); |
| extent_offset = found_key.offset - |
| btrfs_file_extent_offset(leaf, fi); |
| |
| /* FIXME blocksize != 4096 */ |
| num_dec = btrfs_file_extent_num_bytes(leaf, fi); |
| if (extent_start != 0) { |
| found_extent = 1; |
| if (root->ref_cows) |
| inode_sub_bytes(inode, num_dec); |
| } |
| } |
| } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { |
| /* |
| * we can't truncate inline items that have had |
| * special encodings |
| */ |
| if (!del_item && |
| btrfs_file_extent_compression(leaf, fi) == 0 && |
| btrfs_file_extent_encryption(leaf, fi) == 0 && |
| btrfs_file_extent_other_encoding(leaf, fi) == 0) { |
| u32 size = new_size - found_key.offset; |
| |
| if (root->ref_cows) { |
| inode_sub_bytes(inode, item_end + 1 - |
| new_size); |
| } |
| size = |
| btrfs_file_extent_calc_inline_size(size); |
| btrfs_truncate_item(trans, root, path, |
| size, 1); |
| } else if (root->ref_cows) { |
| inode_sub_bytes(inode, item_end + 1 - |
| found_key.offset); |
| } |
| } |
| delete: |
| if (del_item) { |
| if (!pending_del_nr) { |
| /* no pending yet, add ourselves */ |
| pending_del_slot = path->slots[0]; |
| pending_del_nr = 1; |
| } else if (pending_del_nr && |
| path->slots[0] + 1 == pending_del_slot) { |
| /* hop on the pending chunk */ |
| pending_del_nr++; |
| pending_del_slot = path->slots[0]; |
| } else { |
| BUG(); |
| } |
| } else { |
| break; |
| } |
| if (found_extent && (root->ref_cows || |
| root == root->fs_info->tree_root)) { |
| btrfs_set_path_blocking(path); |
| ret = btrfs_free_extent(trans, root, extent_start, |
| extent_num_bytes, 0, |
| btrfs_header_owner(leaf), |
| ino, extent_offset, 0); |
| BUG_ON(ret); |
| } |
| |
| if (found_type == BTRFS_INODE_ITEM_KEY) |
| break; |
| |
| if (path->slots[0] == 0 || |
| path->slots[0] != pending_del_slot) { |
| if (root->ref_cows && |
| BTRFS_I(inode)->location.objectid != |
| BTRFS_FREE_INO_OBJECTID) { |
| err = -EAGAIN; |
| goto out; |
| } |
| if (pending_del_nr) { |
| ret = btrfs_del_items(trans, root, path, |
| pending_del_slot, |
| pending_del_nr); |
| if (ret) { |
| btrfs_abort_transaction(trans, |
| root, ret); |
| goto error; |
| } |
| pending_del_nr = 0; |
| } |
| btrfs_release_path(path); |
| goto search_again; |
| } else { |
| path->slots[0]--; |
| } |
| } |
| out: |
| if (pending_del_nr) { |
| ret = btrfs_del_items(trans, root, path, pending_del_slot, |
| pending_del_nr); |
| if (ret) |
| btrfs_abort_transaction(trans, root, ret); |
| } |
| error: |
| btrfs_free_path(path); |
| return err; |
| } |
| |
| /* |
| * taken from block_truncate_page, but does cow as it zeros out |
| * any bytes left in the last page in the file. |
| */ |
| static int btrfs_truncate_page(struct address_space *mapping, loff_t from) |
| { |
| struct inode *inode = mapping->host; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| char *kaddr; |
| u32 blocksize = root->sectorsize; |
| pgoff_t index = from >> PAGE_CACHE_SHIFT; |
| unsigned offset = from & (PAGE_CACHE_SIZE-1); |
| struct page *page; |
| gfp_t mask = btrfs_alloc_write_mask(mapping); |
| int ret = 0; |
| u64 page_start; |
| u64 page_end; |
| |
| if ((offset & (blocksize - 1)) == 0) |
| goto out; |
| ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); |
| if (ret) |
| goto out; |
| |
| ret = -ENOMEM; |
| again: |
| page = find_or_create_page(mapping, index, mask); |
| if (!page) { |
| btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); |
| goto out; |
| } |
| |
| page_start = page_offset(page); |
| page_end = page_start + PAGE_CACHE_SIZE - 1; |
| |
| if (!PageUptodate(page)) { |
| ret = btrfs_readpage(NULL, page); |
| lock_page(page); |
| if (page->mapping != mapping) { |
| unlock_page(page); |
| page_cache_release(page); |
| goto again; |
| } |
| if (!PageUptodate(page)) { |
| ret = -EIO; |
| goto out_unlock; |
| } |
| } |
| wait_on_page_writeback(page); |
| |
| lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state); |
| set_page_extent_mapped(page); |
| |
| ordered = btrfs_lookup_ordered_extent(inode, page_start); |
| if (ordered) { |
| unlock_extent_cached(io_tree, page_start, page_end, |
| &cached_state, GFP_NOFS); |
| unlock_page(page); |
| page_cache_release(page); |
| btrfs_start_ordered_extent(inode, ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| goto again; |
| } |
| |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, |
| EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING, |
| 0, 0, &cached_state, GFP_NOFS); |
| |
| ret = btrfs_set_extent_delalloc(inode, page_start, page_end, |
| &cached_state); |
| if (ret) { |
| unlock_extent_cached(io_tree, page_start, page_end, |
| &cached_state, GFP_NOFS); |
| goto out_unlock; |
| } |
| |
| ret = 0; |
| if (offset != PAGE_CACHE_SIZE) { |
| kaddr = kmap(page); |
| memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset); |
| flush_dcache_page(page); |
| kunmap(page); |
| } |
| ClearPageChecked(page); |
| set_page_dirty(page); |
| unlock_extent_cached(io_tree, page_start, page_end, &cached_state, |
| GFP_NOFS); |
| |
| out_unlock: |
| if (ret) |
| btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); |
| unlock_page(page); |
| page_cache_release(page); |
| out: |
| return ret; |
| } |
| |
| /* |
| * This function puts in dummy file extents for the area we're creating a hole |
| * for. So if we are truncating this file to a larger size we need to insert |
| * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for |
| * the range between oldsize and size |
| */ |
| int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct extent_map *em = NULL; |
| struct extent_state *cached_state = NULL; |
| u64 mask = root->sectorsize - 1; |
| u64 hole_start = (oldsize + mask) & ~mask; |
| u64 block_end = (size + mask) & ~mask; |
| u64 last_byte; |
| u64 cur_offset; |
| u64 hole_size; |
| int err = 0; |
| |
| if (size <= hole_start) |
| return 0; |
| |
| while (1) { |
| struct btrfs_ordered_extent *ordered; |
| btrfs_wait_ordered_range(inode, hole_start, |
| block_end - hole_start); |
| lock_extent_bits(io_tree, hole_start, block_end - 1, 0, |
| &cached_state); |
| ordered = btrfs_lookup_ordered_extent(inode, hole_start); |
| if (!ordered) |
| break; |
| unlock_extent_cached(io_tree, hole_start, block_end - 1, |
| &cached_state, GFP_NOFS); |
| btrfs_put_ordered_extent(ordered); |
| } |
| |
| cur_offset = hole_start; |
| while (1) { |
| em = btrfs_get_extent(inode, NULL, 0, cur_offset, |
| block_end - cur_offset, 0); |
| if (IS_ERR(em)) { |
| err = PTR_ERR(em); |
| break; |
| } |
| last_byte = min(extent_map_end(em), block_end); |
| last_byte = (last_byte + mask) & ~mask; |
| if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) { |
| u64 hint_byte = 0; |
| hole_size = last_byte - cur_offset; |
| |
| trans = btrfs_start_transaction(root, 3); |
| if (IS_ERR(trans)) { |
| err = PTR_ERR(trans); |
| break; |
| } |
| |
| err = btrfs_drop_extents(trans, inode, cur_offset, |
| cur_offset + hole_size, |
| &hint_byte, 1); |
| if (err) { |
| btrfs_abort_transaction(trans, root, err); |
| btrfs_end_transaction(trans, root); |
| break; |
| } |
| |
| err = btrfs_insert_file_extent(trans, root, |
| btrfs_ino(inode), cur_offset, 0, |
| 0, hole_size, 0, hole_size, |
| 0, 0, 0); |
| if (err) { |
| btrfs_abort_transaction(trans, root, err); |
| btrfs_end_transaction(trans, root); |
| break; |
| } |
| |
| btrfs_drop_extent_cache(inode, hole_start, |
| last_byte - 1, 0); |
| |
| btrfs_update_inode(trans, root, inode); |
| btrfs_end_transaction(trans, root); |
| } |
| free_extent_map(em); |
| em = NULL; |
| cur_offset = last_byte; |
| if (cur_offset >= block_end) |
| break; |
| } |
| |
| free_extent_map(em); |
| unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state, |
| GFP_NOFS); |
| return err; |
| } |
| |
| static int btrfs_setsize(struct inode *inode, loff_t newsize) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| loff_t oldsize = i_size_read(inode); |
| int ret; |
| |
| if (newsize == oldsize) |
| return 0; |
| |
| if (newsize > oldsize) { |
| truncate_pagecache(inode, oldsize, newsize); |
| ret = btrfs_cont_expand(inode, oldsize, newsize); |
| if (ret) |
| return ret; |
| |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| i_size_write(inode, newsize); |
| btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL); |
| ret = btrfs_update_inode(trans, root, inode); |
| btrfs_end_transaction(trans, root); |
| } else { |
| |
| /* |
| * We're truncating a file that used to have good data down to |
| * zero. Make sure it gets into the ordered flush list so that |
| * any new writes get down to disk quickly. |
| */ |
| if (newsize == 0) |
| BTRFS_I(inode)->ordered_data_close = 1; |
| |
| /* we don't support swapfiles, so vmtruncate shouldn't fail */ |
| truncate_setsize(inode, newsize); |
| ret = btrfs_truncate(inode); |
| } |
| |
| return ret; |
| } |
| |
| static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int err; |
| |
| if (btrfs_root_readonly(root)) |
| return -EROFS; |
| |
| err = inode_change_ok(inode, attr); |
| if (err) |
| return err; |
| |
| if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) { |
| err = btrfs_setsize(inode, attr->ia_size); |
| if (err) |
| return err; |
| } |
| |
| if (attr->ia_valid) { |
| setattr_copy(inode, attr); |
| err = btrfs_dirty_inode(inode); |
| |
| if (!err && attr->ia_valid & ATTR_MODE) |
| err = btrfs_acl_chmod(inode); |
| } |
| |
| return err; |
| } |
| |
| void btrfs_evict_inode(struct inode *inode) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_block_rsv *rsv, *global_rsv; |
| u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); |
| unsigned long nr; |
| int ret; |
| |
| trace_btrfs_inode_evict(inode); |
| |
| truncate_inode_pages(&inode->i_data, 0); |
| if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 || |
| btrfs_is_free_space_inode(root, inode))) |
| goto no_delete; |
| |
| if (is_bad_inode(inode)) { |
| btrfs_orphan_del(NULL, inode); |
| goto no_delete; |
| } |
| /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */ |
| btrfs_wait_ordered_range(inode, 0, (u64)-1); |
| |
| if (root->fs_info->log_root_recovering) { |
| BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan)); |
| goto no_delete; |
| } |
| |
| if (inode->i_nlink > 0) { |
| BUG_ON(btrfs_root_refs(&root->root_item) != 0); |
| goto no_delete; |
| } |
| |
| rsv = btrfs_alloc_block_rsv(root); |
| if (!rsv) { |
| btrfs_orphan_del(NULL, inode); |
| goto no_delete; |
| } |
| rsv->size = min_size; |
| global_rsv = &root->fs_info->global_block_rsv; |
| |
| btrfs_i_size_write(inode, 0); |
| |
| /* |
| * This is a bit simpler than btrfs_truncate since |
| * |
| * 1) We've already reserved our space for our orphan item in the |
| * unlink. |
| * 2) We're going to delete the inode item, so we don't need to update |
| * it at all. |
| * |
| * So we just need to reserve some slack space in case we add bytes when |
| * doing the truncate. |
| */ |
| while (1) { |
| ret = btrfs_block_rsv_refill_noflush(root, rsv, min_size); |
| |
| /* |
| * Try and steal from the global reserve since we will |
| * likely not use this space anyway, we want to try as |
| * hard as possible to get this to work. |
| */ |
| if (ret) |
| ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size); |
| |
| if (ret) { |
| printk(KERN_WARNING "Could not get space for a " |
| "delete, will truncate on mount %d\n", ret); |
| btrfs_orphan_del(NULL, inode); |
| btrfs_free_block_rsv(root, rsv); |
| goto no_delete; |
| } |
| |
| trans = btrfs_start_transaction(root, 0); |
| if (IS_ERR(trans)) { |
| btrfs_orphan_del(NULL, inode); |
| btrfs_free_block_rsv(root, rsv); |
| goto no_delete; |
| } |
| |
| trans->block_rsv = rsv; |
| |
| ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0); |
| if (ret != -EAGAIN) |
| break; |
| |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| trans = NULL; |
| btrfs_btree_balance_dirty(root, nr); |
| } |
| |
| btrfs_free_block_rsv(root, rsv); |
| |
| if (ret == 0) { |
| trans->block_rsv = root->orphan_block_rsv; |
| ret = btrfs_orphan_del(trans, inode); |
| BUG_ON(ret); |
| } |
| |
| trans->block_rsv = &root->fs_info->trans_block_rsv; |
| if (!(root == root->fs_info->tree_root || |
| root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)) |
| btrfs_return_ino(root, btrfs_ino(inode)); |
| |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| btrfs_btree_balance_dirty(root, nr); |
| no_delete: |
| end_writeback(inode); |
| return; |
| } |
| |
| /* |
| * this returns the key found in the dir entry in the location pointer. |
| * If no dir entries were found, location->objectid is 0. |
| */ |
| static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry, |
| struct btrfs_key *location) |
| { |
| const char *name = dentry->d_name.name; |
| int namelen = dentry->d_name.len; |
| struct btrfs_dir_item *di; |
| struct btrfs_path *path; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| int ret = 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name, |
| namelen, 0); |
| if (IS_ERR(di)) |
| ret = PTR_ERR(di); |
| |
| if (IS_ERR_OR_NULL(di)) |
| goto out_err; |
| |
| btrfs_dir_item_key_to_cpu(path->nodes[0], di, location); |
| out: |
| btrfs_free_path(path); |
| return ret; |
| out_err: |
| location->objectid = 0; |
| goto out; |
| } |
| |
| /* |
| * when we hit a tree root in a directory, the btrfs part of the inode |
| * needs to be changed to reflect the root directory of the tree root. This |
| * is kind of like crossing a mount point. |
| */ |
| static int fixup_tree_root_location(struct btrfs_root *root, |
| struct inode *dir, |
| struct dentry *dentry, |
| struct btrfs_key *location, |
| struct btrfs_root **sub_root) |
| { |
| struct btrfs_path *path; |
| struct btrfs_root *new_root; |
| struct btrfs_root_ref *ref; |
| struct extent_buffer *leaf; |
| int ret; |
| int err = 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| err = -ENOENT; |
| ret = btrfs_find_root_ref(root->fs_info->tree_root, path, |
| BTRFS_I(dir)->root->root_key.objectid, |
| location->objectid); |
| if (ret) { |
| if (ret < 0) |
| err = ret; |
| goto out; |
| } |
| |
| leaf = path->nodes[0]; |
| ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref); |
| if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) || |
| btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len) |
| goto out; |
| |
| ret = memcmp_extent_buffer(leaf, dentry->d_name.name, |
| (unsigned long)(ref + 1), |
| dentry->d_name.len); |
| if (ret) |
| goto out; |
| |
| btrfs_release_path(path); |
| |
| new_root = btrfs_read_fs_root_no_name(root->fs_info, location); |
| if (IS_ERR(new_root)) { |
| err = PTR_ERR(new_root); |
| goto out; |
| } |
| |
| if (btrfs_root_refs(&new_root->root_item) == 0) { |
| err = -ENOENT; |
| goto out; |
| } |
| |
| *sub_root = new_root; |
| location->objectid = btrfs_root_dirid(&new_root->root_item); |
| location->type = BTRFS_INODE_ITEM_KEY; |
| location->offset = 0; |
| err = 0; |
| out: |
| btrfs_free_path(path); |
| return err; |
| } |
| |
| static void inode_tree_add(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_inode *entry; |
| struct rb_node **p; |
| struct rb_node *parent; |
| u64 ino = btrfs_ino(inode); |
| again: |
| p = &root->inode_tree.rb_node; |
| parent = NULL; |
| |
| if (inode_unhashed(inode)) |
| return; |
| |
| spin_lock(&root->inode_lock); |
| while (*p) { |
| parent = *p; |
| entry = rb_entry(parent, struct btrfs_inode, rb_node); |
| |
| if (ino < btrfs_ino(&entry->vfs_inode)) |
| p = &parent->rb_left; |
| else if (ino > btrfs_ino(&entry->vfs_inode)) |
| p = &parent->rb_right; |
| else { |
| WARN_ON(!(entry->vfs_inode.i_state & |
| (I_WILL_FREE | I_FREEING))); |
| rb_erase(parent, &root->inode_tree); |
| RB_CLEAR_NODE(parent); |
| spin_unlock(&root->inode_lock); |
| goto again; |
| } |
| } |
| rb_link_node(&BTRFS_I(inode)->rb_node, parent, p); |
| rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree); |
| spin_unlock(&root->inode_lock); |
| } |
| |
| static void inode_tree_del(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int empty = 0; |
| |
| spin_lock(&root->inode_lock); |
| if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) { |
| rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree); |
| RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node); |
| empty = RB_EMPTY_ROOT(&root->inode_tree); |
| } |
| spin_unlock(&root->inode_lock); |
| |
| /* |
| * Free space cache has inodes in the tree root, but the tree root has a |
| * root_refs of 0, so this could end up dropping the tree root as a |
| * snapshot, so we need the extra !root->fs_info->tree_root check to |
| * make sure we don't drop it. |
| */ |
| if (empty && btrfs_root_refs(&root->root_item) == 0 && |
| root != root->fs_info->tree_root) { |
| synchronize_srcu(&root->fs_info->subvol_srcu); |
| spin_lock(&root->inode_lock); |
| empty = RB_EMPTY_ROOT(&root->inode_tree); |
| spin_unlock(&root->inode_lock); |
| if (empty) |
| btrfs_add_dead_root(root); |
| } |
| } |
| |
| void btrfs_invalidate_inodes(struct btrfs_root *root) |
| { |
| struct rb_node *node; |
| struct rb_node *prev; |
| struct btrfs_inode *entry; |
| struct inode *inode; |
| u64 objectid = 0; |
| |
| WARN_ON(btrfs_root_refs(&root->root_item) != 0); |
| |
| spin_lock(&root->inode_lock); |
| again: |
| node = root->inode_tree.rb_node; |
| prev = NULL; |
| while (node) { |
| prev = node; |
| entry = rb_entry(node, struct btrfs_inode, rb_node); |
| |
| if (objectid < btrfs_ino(&entry->vfs_inode)) |
| node = node->rb_left; |
| else if (objectid > btrfs_ino(&entry->vfs_inode)) |
| node = node->rb_right; |
| else |
| break; |
| } |
| if (!node) { |
| while (prev) { |
| entry = rb_entry(prev, struct btrfs_inode, rb_node); |
| if (objectid <= btrfs_ino(&entry->vfs_inode)) { |
| node = prev; |
| break; |
| } |
| prev = rb_next(prev); |
| } |
| } |
| while (node) { |
| entry = rb_entry(node, struct btrfs_inode, rb_node); |
| objectid = btrfs_ino(&entry->vfs_inode) + 1; |
| inode = igrab(&entry->vfs_inode); |
| if (inode) { |
| spin_unlock(&root->inode_lock); |
| if (atomic_read(&inode->i_count) > 1) |
| d_prune_aliases(inode); |
| /* |
| * btrfs_drop_inode will have it removed from |
| * the inode cache when its usage count |
| * hits zero. |
| */ |
| iput(inode); |
| cond_resched(); |
| spin_lock(&root->inode_lock); |
| goto again; |
| } |
| |
| if (cond_resched_lock(&root->inode_lock)) |
| goto again; |
| |
| node = rb_next(node); |
| } |
| spin_unlock(&root->inode_lock); |
| } |
| |
| static int btrfs_init_locked_inode(struct inode *inode, void *p) |
| { |
| struct btrfs_iget_args *args = p; |
| inode->i_ino = args->ino; |
| BTRFS_I(inode)->root = args->root; |
| btrfs_set_inode_space_info(args->root, inode); |
| return 0; |
| } |
| |
| static int btrfs_find_actor(struct inode *inode, void *opaque) |
| { |
| struct btrfs_iget_args *args = opaque; |
| return args->ino == btrfs_ino(inode) && |
| args->root == BTRFS_I(inode)->root; |
| } |
| |
| static struct inode *btrfs_iget_locked(struct super_block *s, |
| u64 objectid, |
| struct btrfs_root *root) |
| { |
| struct inode *inode; |
| struct btrfs_iget_args args; |
| args.ino = objectid; |
| args.root = root; |
| |
| inode = iget5_locked(s, objectid, btrfs_find_actor, |
| btrfs_init_locked_inode, |
| (void *)&args); |
| return inode; |
| } |
| |
| /* Get an inode object given its location and corresponding root. |
| * Returns in *is_new if the inode was read from disk |
| */ |
| struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, |
| struct btrfs_root *root, int *new) |
| { |
| struct inode *inode; |
| |
| inode = btrfs_iget_locked(s, location->objectid, root); |
| if (!inode) |
| return ERR_PTR(-ENOMEM); |
| |
| if (inode->i_state & I_NEW) { |
| BTRFS_I(inode)->root = root; |
| memcpy(&BTRFS_I(inode)->location, location, sizeof(*location)); |
| btrfs_read_locked_inode(inode); |
| if (!is_bad_inode(inode)) { |
| inode_tree_add(inode); |
| unlock_new_inode(inode); |
| if (new) |
| *new = 1; |
| } else { |
| unlock_new_inode(inode); |
| iput(inode); |
| inode = ERR_PTR(-ESTALE); |
| } |
| } |
| |
| return inode; |
| } |
| |
| static struct inode *new_simple_dir(struct super_block *s, |
| struct btrfs_key *key, |
| struct btrfs_root *root) |
| { |
| struct inode *inode = new_inode(s); |
| |
| if (!inode) |
| return ERR_PTR(-ENOMEM); |
| |
| BTRFS_I(inode)->root = root; |
| memcpy(&BTRFS_I(inode)->location, key, sizeof(*key)); |
| BTRFS_I(inode)->dummy_inode = 1; |
| |
| inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID; |
| inode->i_op = &btrfs_dir_ro_inode_operations; |
| inode->i_fop = &simple_dir_operations; |
| inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO; |
| inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; |
| |
| return inode; |
| } |
| |
| struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry) |
| { |
| struct inode *inode; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_root *sub_root = root; |
| struct btrfs_key location; |
| int index; |
| int ret = 0; |
| |
| if (dentry->d_name.len > BTRFS_NAME_LEN) |
| return ERR_PTR(-ENAMETOOLONG); |
| |
| if (unlikely(d_need_lookup(dentry))) { |
| memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key)); |
| kfree(dentry->d_fsdata); |
| dentry->d_fsdata = NULL; |
| /* This thing is hashed, drop it for now */ |
| d_drop(dentry); |
| } else { |
| ret = btrfs_inode_by_name(dir, dentry, &location); |
| } |
| |
| if (ret < 0) |
| return ERR_PTR(ret); |
| |
| if (location.objectid == 0) |
| return NULL; |
| |
| if (location.type == BTRFS_INODE_ITEM_KEY) { |
| inode = btrfs_iget(dir->i_sb, &location, root, NULL); |
| return inode; |
| } |
| |
| BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY); |
| |
| index = srcu_read_lock(&root->fs_info->subvol_srcu); |
| ret = fixup_tree_root_location(root, dir, dentry, |
| &location, &sub_root); |
| if (ret < 0) { |
| if (ret != -ENOENT) |
| inode = ERR_PTR(ret); |
| else |
| inode = new_simple_dir(dir->i_sb, &location, sub_root); |
| } else { |
| inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL); |
| } |
| srcu_read_unlock(&root->fs_info->subvol_srcu, index); |
| |
| if (!IS_ERR(inode) && root != sub_root) { |
| down_read(&root->fs_info->cleanup_work_sem); |
| if (!(inode->i_sb->s_flags & MS_RDONLY)) |
| ret = btrfs_orphan_cleanup(sub_root); |
| up_read(&root->fs_info->cleanup_work_sem); |
| if (ret) |
| inode = ERR_PTR(ret); |
| } |
| |
| return inode; |
| } |
| |
| static int btrfs_dentry_delete(const struct dentry *dentry) |
| { |
| struct btrfs_root *root; |
| struct inode *inode = dentry->d_inode; |
| |
| if (!inode && !IS_ROOT(dentry)) |
| inode = dentry->d_parent->d_inode; |
| |
| if (inode) { |
| root = BTRFS_I(inode)->root; |
| if (btrfs_root_refs(&root->root_item) == 0) |
| return 1; |
| |
| if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) |
| return 1; |
| } |
| return 0; |
| } |
| |
| static void btrfs_dentry_release(struct dentry *dentry) |
| { |
| if (dentry->d_fsdata) |
| kfree(dentry->d_fsdata); |
| } |
| |
| static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry, |
| unsigned int flags) |
| { |
| struct dentry *ret; |
| |
| ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry); |
| if (unlikely(d_need_lookup(dentry))) { |
| spin_lock(&dentry->d_lock); |
| dentry->d_flags &= ~DCACHE_NEED_LOOKUP; |
| spin_unlock(&dentry->d_lock); |
| } |
| return ret; |
| } |
| |
| unsigned char btrfs_filetype_table[] = { |
| DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK |
| }; |
| |
| static int btrfs_real_readdir(struct file *filp, void *dirent, |
| filldir_t filldir) |
| { |
| struct inode *inode = filp->f_dentry->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_item *item; |
| struct btrfs_dir_item *di; |
| struct btrfs_key key; |
| struct btrfs_key found_key; |
| struct btrfs_path *path; |
| struct list_head ins_list; |
| struct list_head del_list; |
| int ret; |
| struct extent_buffer *leaf; |
| int slot; |
| unsigned char d_type; |
| int over = 0; |
| u32 di_cur; |
| u32 di_total; |
| u32 di_len; |
| int key_type = BTRFS_DIR_INDEX_KEY; |
| char tmp_name[32]; |
| char *name_ptr; |
| int name_len; |
| int is_curr = 0; /* filp->f_pos points to the current index? */ |
| |
| /* FIXME, use a real flag for deciding about the key type */ |
| if (root->fs_info->tree_root == root) |
| key_type = BTRFS_DIR_ITEM_KEY; |
| |
| /* special case for "." */ |
| if (filp->f_pos == 0) { |
| over = filldir(dirent, ".", 1, |
| filp->f_pos, btrfs_ino(inode), DT_DIR); |
| if (over) |
| return 0; |
| filp->f_pos = 1; |
| } |
| /* special case for .., just use the back ref */ |
| if (filp->f_pos == 1) { |
| u64 pino = parent_ino(filp->f_path.dentry); |
| over = filldir(dirent, "..", 2, |
| filp->f_pos, pino, DT_DIR); |
| if (over) |
| return 0; |
| filp->f_pos = 2; |
| } |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| path->reada = 1; |
| |
| if (key_type == BTRFS_DIR_INDEX_KEY) { |
| INIT_LIST_HEAD(&ins_list); |
| INIT_LIST_HEAD(&del_list); |
| btrfs_get_delayed_items(inode, &ins_list, &del_list); |
| } |
| |
| btrfs_set_key_type(&key, key_type); |
| key.offset = filp->f_pos; |
| key.objectid = btrfs_ino(inode); |
| |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto err; |
| |
| while (1) { |
| leaf = path->nodes[0]; |
| slot = path->slots[0]; |
| if (slot >= btrfs_header_nritems(leaf)) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret < 0) |
| goto err; |
| else if (ret > 0) |
| break; |
| continue; |
| } |
| |
| item = btrfs_item_nr(leaf, slot); |
| btrfs_item_key_to_cpu(leaf, &found_key, slot); |
| |
| if (found_key.objectid != key.objectid) |
| break; |
| if (btrfs_key_type(&found_key) != key_type) |
| break; |
| if (found_key.offset < filp->f_pos) |
| goto next; |
| if (key_type == BTRFS_DIR_INDEX_KEY && |
| btrfs_should_delete_dir_index(&del_list, |
| found_key.offset)) |
| goto next; |
| |
| filp->f_pos = found_key.offset; |
| is_curr = 1; |
| |
| di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); |
| di_cur = 0; |
| di_total = btrfs_item_size(leaf, item); |
| |
| while (di_cur < di_total) { |
| struct btrfs_key location; |
| |
| if (verify_dir_item(root, leaf, di)) |
| break; |
| |
| name_len = btrfs_dir_name_len(leaf, di); |
| if (name_len <= sizeof(tmp_name)) { |
| name_ptr = tmp_name; |
| } else { |
| name_ptr = kmalloc(name_len, GFP_NOFS); |
| if (!name_ptr) { |
| ret = -ENOMEM; |
| goto err; |
| } |
| } |
| read_extent_buffer(leaf, name_ptr, |
| (unsigned long)(di + 1), name_len); |
| |
| d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)]; |
| btrfs_dir_item_key_to_cpu(leaf, di, &location); |
| |
| |
| /* is this a reference to our own snapshot? If so |
| * skip it. |
| * |
| * In contrast to old kernels, we insert the snapshot's |
| * dir item and dir index after it has been created, so |
| * we won't find a reference to our own snapshot. We |
| * still keep the following code for backward |
| * compatibility. |
| */ |
| if (location.type == BTRFS_ROOT_ITEM_KEY && |
| location.objectid == root->root_key.objectid) { |
| over = 0; |
| goto skip; |
| } |
| over = filldir(dirent, name_ptr, name_len, |
| found_key.offset, location.objectid, |
| d_type); |
| |
| skip: |
| if (name_ptr != tmp_name) |
| kfree(name_ptr); |
| |
| if (over) |
| goto nopos; |
| di_len = btrfs_dir_name_len(leaf, di) + |
| btrfs_dir_data_len(leaf, di) + sizeof(*di); |
| di_cur += di_len; |
| di = (struct btrfs_dir_item *)((char *)di + di_len); |
| } |
| next: |
| path->slots[0]++; |
| } |
| |
| if (key_type == BTRFS_DIR_INDEX_KEY) { |
| if (is_curr) |
| filp->f_pos++; |
| ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir, |
| &ins_list); |
| if (ret) |
| goto nopos; |
| } |
| |
| /* Reached end of directory/root. Bump pos past the last item. */ |
| if (key_type == BTRFS_DIR_INDEX_KEY) |
| /* |
| * 32-bit glibc will use getdents64, but then strtol - |
| * so the last number we can serve is this. |
| */ |
| filp->f_pos = 0x7fffffff; |
| else |
| filp->f_pos++; |
| nopos: |
| ret = 0; |
| err: |
| if (key_type == BTRFS_DIR_INDEX_KEY) |
| btrfs_put_delayed_items(&ins_list, &del_list); |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| int ret = 0; |
| bool nolock = false; |
| |
| if (BTRFS_I(inode)->dummy_inode) |
| return 0; |
| |
| if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(root, inode)) |
| nolock = true; |
| |
| if (wbc->sync_mode == WB_SYNC_ALL) { |
| if (nolock) |
| trans = btrfs_join_transaction_nolock(root); |
| else |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| if (nolock) |
| ret = btrfs_end_transaction_nolock(trans, root); |
| else |
| ret = btrfs_commit_transaction(trans, root); |
| } |
| return ret; |
| } |
| |
| /* |
| * This is somewhat expensive, updating the tree every time the |
| * inode changes. But, it is most likely to find the inode in cache. |
| * FIXME, needs more benchmarking...there are no reasons other than performance |
| * to keep or drop this code. |
| */ |
| int btrfs_dirty_inode(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| int ret; |
| |
| if (BTRFS_I(inode)->dummy_inode) |
| return 0; |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret && ret == -ENOSPC) { |
| /* whoops, lets try again with the full transaction */ |
| btrfs_end_transaction(trans, root); |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| ret = btrfs_update_inode(trans, root, inode); |
| } |
| btrfs_end_transaction(trans, root); |
| if (BTRFS_I(inode)->delayed_node) |
| btrfs_balance_delayed_items(root); |
| |
| return ret; |
| } |
| |
| /* |
| * This is a copy of file_update_time. We need this so we can return error on |
| * ENOSPC for updating the inode in the case of file write and mmap writes. |
| */ |
| int btrfs_update_time(struct file *file) |
| { |
| struct inode *inode = file->f_path.dentry->d_inode; |
| struct timespec now; |
| int ret; |
| enum { S_MTIME = 1, S_CTIME = 2, S_VERSION = 4 } sync_it = 0; |
| |
| /* First try to exhaust all avenues to not sync */ |
| if (IS_NOCMTIME(inode)) |
| return 0; |
| |
| now = current_fs_time(inode->i_sb); |
| if (!timespec_equal(&inode->i_mtime, &now)) |
| sync_it = S_MTIME; |
| |
| if (!timespec_equal(&inode->i_ctime, &now)) |
| sync_it |= S_CTIME; |
| |
| if (IS_I_VERSION(inode)) |
| sync_it |= S_VERSION; |
| |
| if (!sync_it) |
| return 0; |
| |
| /* Finally allowed to write? Takes lock. */ |
| if (mnt_want_write_file(file)) |
| return 0; |
| |
| /* Only change inode inside the lock region */ |
| if (sync_it & S_VERSION) |
| inode_inc_iversion(inode); |
| if (sync_it & S_CTIME) |
| inode->i_ctime = now; |
| if (sync_it & S_MTIME) |
| inode->i_mtime = now; |
| ret = btrfs_dirty_inode(inode); |
| if (!ret) |
| mark_inode_dirty_sync(inode); |
| mnt_drop_write(file->f_path.mnt); |
| return ret; |
| } |
| |
| /* |
| * find the highest existing sequence number in a directory |
| * and then set the in-memory index_cnt variable to reflect |
| * free sequence numbers |
| */ |
| static int btrfs_set_inode_index_count(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_key key, found_key; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| int ret; |
| |
| key.objectid = btrfs_ino(inode); |
| btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY); |
| key.offset = (u64)-1; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| /* FIXME: we should be able to handle this */ |
| if (ret == 0) |
| goto out; |
| ret = 0; |
| |
| /* |
| * MAGIC NUMBER EXPLANATION: |
| * since we search a directory based on f_pos we have to start at 2 |
| * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody |
| * else has to start at 2 |
| */ |
| if (path->slots[0] == 0) { |
| BTRFS_I(inode)->index_cnt = 2; |
| goto out; |
| } |
| |
| path->slots[0]--; |
| |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| |
| if (found_key.objectid != btrfs_ino(inode) || |
| btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) { |
| BTRFS_I(inode)->index_cnt = 2; |
| goto out; |
| } |
| |
| BTRFS_I(inode)->index_cnt = found_key.offset + 1; |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * helper to find a free sequence number in a given directory. This current |
| * code is very simple, later versions will do smarter things in the btree |
| */ |
| int btrfs_set_inode_index(struct inode *dir, u64 *index) |
| { |
| int ret = 0; |
| |
| if (BTRFS_I(dir)->index_cnt == (u64)-1) { |
| ret = btrfs_inode_delayed_dir_index_count(dir); |
| if (ret) { |
| ret = btrfs_set_inode_index_count(dir); |
| if (ret) |
| return ret; |
| } |
| } |
| |
| *index = BTRFS_I(dir)->index_cnt; |
| BTRFS_I(dir)->index_cnt++; |
| |
| return ret; |
| } |
| |
| static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *dir, |
| const char *name, int name_len, |
| u64 ref_objectid, u64 objectid, |
| umode_t mode, u64 *index) |
| { |
| struct inode *inode; |
| struct btrfs_inode_item *inode_item; |
| struct btrfs_key *location; |
| struct btrfs_path *path; |
| struct btrfs_inode_ref *ref; |
| struct btrfs_key key[2]; |
| u32 sizes[2]; |
| unsigned long ptr; |
| int ret; |
| int owner; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return ERR_PTR(-ENOMEM); |
| |
| inode = new_inode(root->fs_info->sb); |
| if (!inode) { |
| btrfs_free_path(path); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| /* |
| * we have to initialize this early, so we can reclaim the inode |
| * number if we fail afterwards in this function. |
| */ |
| inode->i_ino = objectid; |
| |
| if (dir) { |
| trace_btrfs_inode_request(dir); |
| |
| ret = btrfs_set_inode_index(dir, index); |
| if (ret) { |
| btrfs_free_path(path); |
| iput(inode); |
| return ERR_PTR(ret); |
| } |
| } |
| /* |
| * index_cnt is ignored for everything but a dir, |
| * btrfs_get_inode_index_count has an explanation for the magic |
| * number |
| */ |
| BTRFS_I(inode)->index_cnt = 2; |
| BTRFS_I(inode)->root = root; |
| BTRFS_I(inode)->generation = trans->transid; |
| inode->i_generation = BTRFS_I(inode)->generation; |
| btrfs_set_inode_space_info(root, inode); |
| |
| if (S_ISDIR(mode)) |
| owner = 0; |
| else |
| owner = 1; |
| |
| key[0].objectid = objectid; |
| btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY); |
| key[0].offset = 0; |
| |
| key[1].objectid = objectid; |
| btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY); |
| key[1].offset = ref_objectid; |
| |
| sizes[0] = sizeof(struct btrfs_inode_item); |
| sizes[1] = name_len + sizeof(*ref); |
| |
| path->leave_spinning = 1; |
| ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2); |
| if (ret != 0) |
| goto fail; |
| |
| inode_init_owner(inode, dir, mode); |
| inode_set_bytes(inode, 0); |
| inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; |
| inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_inode_item); |
| fill_inode_item(trans, path->nodes[0], inode_item, inode); |
| |
| ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1, |
| struct btrfs_inode_ref); |
| btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len); |
| btrfs_set_inode_ref_index(path->nodes[0], ref, *index); |
| ptr = (unsigned long)(ref + 1); |
| write_extent_buffer(path->nodes[0], name, ptr, name_len); |
| |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| btrfs_free_path(path); |
| |
| location = &BTRFS_I(inode)->location; |
| location->objectid = objectid; |
| location->offset = 0; |
| btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY); |
| |
| btrfs_inherit_iflags(inode, dir); |
| |
| if (S_ISREG(mode)) { |
| if (btrfs_test_opt(root, NODATASUM)) |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM; |
| if (btrfs_test_opt(root, NODATACOW) || |
| (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW)) |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW; |
| } |
| |
| insert_inode_hash(inode); |
| inode_tree_add(inode); |
| |
| trace_btrfs_inode_new(inode); |
| btrfs_set_inode_last_trans(trans, inode); |
| |
| return inode; |
| fail: |
| if (dir) |
| BTRFS_I(dir)->index_cnt--; |
| btrfs_free_path(path); |
| iput(inode); |
| return ERR_PTR(ret); |
| } |
| |
| static inline u8 btrfs_inode_type(struct inode *inode) |
| { |
| return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT]; |
| } |
| |
| /* |
| * utility function to add 'inode' into 'parent_inode' with |
| * a give name and a given sequence number. |
| * if 'add_backref' is true, also insert a backref from the |
| * inode to the parent directory. |
| */ |
| int btrfs_add_link(struct btrfs_trans_handle *trans, |
| struct inode *parent_inode, struct inode *inode, |
| const char *name, int name_len, int add_backref, u64 index) |
| { |
| int ret = 0; |
| struct btrfs_key key; |
| struct btrfs_root *root = BTRFS_I(parent_inode)->root; |
| u64 ino = btrfs_ino(inode); |
| u64 parent_ino = btrfs_ino(parent_inode); |
| |
| if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { |
| memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key)); |
| } else { |
| key.objectid = ino; |
| btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); |
| key.offset = 0; |
| } |
| |
| if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { |
| ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, |
| key.objectid, root->root_key.objectid, |
| parent_ino, index, name, name_len); |
| } else if (add_backref) { |
| ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino, |
| parent_ino, index); |
| } |
| |
| /* Nothing to clean up yet */ |
| if (ret) |
| return ret; |
| |
| ret = btrfs_insert_dir_item(trans, root, name, name_len, |
| parent_inode, &key, |
| btrfs_inode_type(inode), index); |
| if (ret == -EEXIST) |
| goto fail_dir_item; |
| else if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| return ret; |
| } |
| |
| btrfs_i_size_write(parent_inode, parent_inode->i_size + |
| name_len * 2); |
| parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME; |
| ret = btrfs_update_inode(trans, root, parent_inode); |
| if (ret) |
| btrfs_abort_transaction(trans, root, ret); |
| return ret; |
| |
| fail_dir_item: |
| if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) { |
| u64 local_index; |
| int err; |
| err = btrfs_del_root_ref(trans, root->fs_info->tree_root, |
| key.objectid, root->root_key.objectid, |
| parent_ino, &local_index, name, name_len); |
| |
| } else if (add_backref) { |
| u64 local_index; |
| int err; |
| |
| err = btrfs_del_inode_ref(trans, root, name, name_len, |
| ino, parent_ino, &local_index); |
| } |
| return ret; |
| } |
| |
| static int btrfs_add_nondir(struct btrfs_trans_handle *trans, |
| struct inode *dir, struct dentry *dentry, |
| struct inode *inode, int backref, u64 index) |
| { |
| int err = btrfs_add_link(trans, dir, inode, |
| dentry->d_name.name, dentry->d_name.len, |
| backref, index); |
| if (err > 0) |
| err = -EEXIST; |
| return err; |
| } |
| |
| static int btrfs_mknod(struct inode *dir, struct dentry *dentry, |
| umode_t mode, dev_t rdev) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct inode *inode = NULL; |
| int err; |
| int drop_inode = 0; |
| u64 objectid; |
| unsigned long nr = 0; |
| u64 index = 0; |
| |
| if (!new_valid_dev(rdev)) |
| return -EINVAL; |
| |
| /* |
| * 2 for inode item and ref |
| * 2 for dir items |
| * 1 for xattr if selinux is on |
| */ |
| trans = btrfs_start_transaction(root, 5); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| err = btrfs_find_free_ino(root, &objectid); |
| if (err) |
| goto out_unlock; |
| |
| inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, |
| dentry->d_name.len, btrfs_ino(dir), objectid, |
| mode, &index); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto out_unlock; |
| } |
| |
| err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); |
| if (err) { |
| drop_inode = 1; |
| goto out_unlock; |
| } |
| |
| /* |
| * If the active LSM wants to access the inode during |
| * d_instantiate it needs these. Smack checks to see |
| * if the filesystem supports xattrs by looking at the |
| * ops vector. |
| */ |
| |
| inode->i_op = &btrfs_special_inode_operations; |
| err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); |
| if (err) |
| drop_inode = 1; |
| else { |
| init_special_inode(inode, inode->i_mode, rdev); |
| btrfs_update_inode(trans, root, inode); |
| d_instantiate(dentry, inode); |
| } |
| out_unlock: |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| btrfs_btree_balance_dirty(root, nr); |
| if (drop_inode) { |
| inode_dec_link_count(inode); |
| iput(inode); |
| } |
| return err; |
| } |
| |
| static int btrfs_create(struct inode *dir, struct dentry *dentry, |
| umode_t mode, struct nameidata *nd) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct inode *inode = NULL; |
| int drop_inode = 0; |
| int err; |
| unsigned long nr = 0; |
| u64 objectid; |
| u64 index = 0; |
| |
| /* |
| * 2 for inode item and ref |
| * 2 for dir items |
| * 1 for xattr if selinux is on |
| */ |
| trans = btrfs_start_transaction(root, 5); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| err = btrfs_find_free_ino(root, &objectid); |
| if (err) |
| goto out_unlock; |
| |
| inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, |
| dentry->d_name.len, btrfs_ino(dir), objectid, |
| mode, &index); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto out_unlock; |
| } |
| |
| err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); |
| if (err) { |
| drop_inode = 1; |
| goto out_unlock; |
| } |
| |
| /* |
| * If the active LSM wants to access the inode during |
| * d_instantiate it needs these. Smack checks to see |
| * if the filesystem supports xattrs by looking at the |
| * ops vector. |
| */ |
| inode->i_fop = &btrfs_file_operations; |
| inode->i_op = &btrfs_file_inode_operations; |
| |
| err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); |
| if (err) |
| drop_inode = 1; |
| else { |
| inode->i_mapping->a_ops = &btrfs_aops; |
| inode->i_mapping->backing_dev_info = &root->fs_info->bdi; |
| BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; |
| d_instantiate(dentry, inode); |
| } |
| out_unlock: |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| if (drop_inode) { |
| inode_dec_link_count(inode); |
| iput(inode); |
| } |
| btrfs_btree_balance_dirty(root, nr); |
| return err; |
| } |
| |
| static int btrfs_link(struct dentry *old_dentry, struct inode *dir, |
| struct dentry *dentry) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct inode *inode = old_dentry->d_inode; |
| u64 index; |
| unsigned long nr = 0; |
| int err; |
| int drop_inode = 0; |
| |
| /* do not allow sys_link's with other subvols of the same device */ |
| if (root->objectid != BTRFS_I(inode)->root->objectid) |
| return -EXDEV; |
| |
| if (inode->i_nlink == ~0U) |
| return -EMLINK; |
| |
| err = btrfs_set_inode_index(dir, &index); |
| if (err) |
| goto fail; |
| |
| /* |
| * 2 items for inode and inode ref |
| * 2 items for dir items |
| * 1 item for parent inode |
| */ |
| trans = btrfs_start_transaction(root, 5); |
| if (IS_ERR(trans)) { |
| err = PTR_ERR(trans); |
| goto fail; |
| } |
| |
| btrfs_inc_nlink(inode); |
| inode->i_ctime = CURRENT_TIME; |
| ihold(inode); |
| |
| err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index); |
| |
| if (err) { |
| drop_inode = 1; |
| } else { |
| struct dentry *parent = dentry->d_parent; |
| err = btrfs_update_inode(trans, root, inode); |
| if (err) |
| goto fail; |
| d_instantiate(dentry, inode); |
| btrfs_log_new_name(trans, inode, NULL, parent); |
| } |
| |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| fail: |
| if (drop_inode) { |
| inode_dec_link_count(inode); |
| iput(inode); |
| } |
| btrfs_btree_balance_dirty(root, nr); |
| return err; |
| } |
| |
| static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) |
| { |
| struct inode *inode = NULL; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| int err = 0; |
| int drop_on_err = 0; |
| u64 objectid = 0; |
| u64 index = 0; |
| unsigned long nr = 1; |
| |
| /* |
| * 2 items for inode and ref |
| * 2 items for dir items |
| * 1 for xattr if selinux is on |
| */ |
| trans = btrfs_start_transaction(root, 5); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| err = btrfs_find_free_ino(root, &objectid); |
| if (err) |
| goto out_fail; |
| |
| inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, |
| dentry->d_name.len, btrfs_ino(dir), objectid, |
| S_IFDIR | mode, &index); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto out_fail; |
| } |
| |
| drop_on_err = 1; |
| |
| err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); |
| if (err) |
| goto out_fail; |
| |
| inode->i_op = &btrfs_dir_inode_operations; |
| inode->i_fop = &btrfs_dir_file_operations; |
| |
| btrfs_i_size_write(inode, 0); |
| err = btrfs_update_inode(trans, root, inode); |
| if (err) |
| goto out_fail; |
| |
| err = btrfs_add_link(trans, dir, inode, dentry->d_name.name, |
| dentry->d_name.len, 0, index); |
| if (err) |
| goto out_fail; |
| |
| d_instantiate(dentry, inode); |
| drop_on_err = 0; |
| |
| out_fail: |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| if (drop_on_err) |
| iput(inode); |
| btrfs_btree_balance_dirty(root, nr); |
| return err; |
| } |
| |
| /* helper for btfs_get_extent. Given an existing extent in the tree, |
| * and an extent that you want to insert, deal with overlap and insert |
| * the new extent into the tree. |
| */ |
| static int merge_extent_mapping(struct extent_map_tree *em_tree, |
| struct extent_map *existing, |
| struct extent_map *em, |
| u64 map_start, u64 map_len) |
| { |
| u64 start_diff; |
| |
| BUG_ON(map_start < em->start || map_start >= extent_map_end(em)); |
| start_diff = map_start - em->start; |
| em->start = map_start; |
| em->len = map_len; |
| if (em->block_start < EXTENT_MAP_LAST_BYTE && |
| !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) { |
| em->block_start += start_diff; |
| em->block_len -= start_diff; |
| } |
| return add_extent_mapping(em_tree, em); |
| } |
| |
| static noinline int uncompress_inline(struct btrfs_path *path, |
| struct inode *inode, struct page *page, |
| size_t pg_offset, u64 extent_offset, |
| struct btrfs_file_extent_item *item) |
| { |
| int ret; |
| struct extent_buffer *leaf = path->nodes[0]; |
| char *tmp; |
| size_t max_size; |
| unsigned long inline_size; |
| unsigned long ptr; |
| int compress_type; |
| |
| WARN_ON(pg_offset != 0); |
| compress_type = btrfs_file_extent_compression(leaf, item); |
| max_size = btrfs_file_extent_ram_bytes(leaf, item); |
| inline_size = btrfs_file_extent_inline_item_len(leaf, |
| btrfs_item_nr(leaf, path->slots[0])); |
| tmp = kmalloc(inline_size, GFP_NOFS); |
| if (!tmp) |
| return -ENOMEM; |
| ptr = btrfs_file_extent_inline_start(item); |
| |
| read_extent_buffer(leaf, tmp, ptr, inline_size); |
| |
| max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size); |
| ret = btrfs_decompress(compress_type, tmp, page, |
| extent_offset, inline_size, max_size); |
| if (ret) { |
| char *kaddr = kmap_atomic(page); |
| unsigned long copy_size = min_t(u64, |
| PAGE_CACHE_SIZE - pg_offset, |
| max_size - extent_offset); |
| memset(kaddr + pg_offset, 0, copy_size); |
| kunmap_atomic(kaddr); |
| } |
| kfree(tmp); |
| return 0; |
| } |
| |
| /* |
| * a bit scary, this does extent mapping from logical file offset to the disk. |
| * the ugly parts come from merging extents from the disk with the in-ram |
| * representation. This gets more complex because of the data=ordered code, |
| * where the in-ram extents might be locked pending data=ordered completion. |
| * |
| * This also copies inline extents directly into the page. |
| */ |
| |
| struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page, |
| size_t pg_offset, u64 start, u64 len, |
| int create) |
| { |
| int ret; |
| int err = 0; |
| u64 bytenr; |
| u64 extent_start = 0; |
| u64 extent_end = 0; |
| u64 objectid = btrfs_ino(inode); |
| u32 found_type; |
| struct btrfs_path *path = NULL; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_file_extent_item *item; |
| struct extent_buffer *leaf; |
| struct btrfs_key found_key; |
| struct extent_map *em = NULL; |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct btrfs_trans_handle *trans = NULL; |
| int compress_type; |
| |
| again: |
| read_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, start, len); |
| if (em) |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| read_unlock(&em_tree->lock); |
| |
| if (em) { |
| if (em->start > start || em->start + em->len <= start) |
| free_extent_map(em); |
| else if (em->block_start == EXTENT_MAP_INLINE && page) |
| free_extent_map(em); |
| else |
| goto out; |
| } |
| em = alloc_extent_map(); |
| if (!em) { |
| err = -ENOMEM; |
| goto out; |
| } |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| em->start = EXTENT_MAP_HOLE; |
| em->orig_start = EXTENT_MAP_HOLE; |
| em->len = (u64)-1; |
| em->block_len = (u64)-1; |
| |
| if (!path) { |
| path = btrfs_alloc_path(); |
| if (!path) { |
| err = -ENOMEM; |
| goto out; |
| } |
| /* |
| * Chances are we'll be called again, so go ahead and do |
| * readahead |
| */ |
| path->reada = 1; |
| } |
| |
| ret = btrfs_lookup_file_extent(trans, root, path, |
| objectid, start, trans != NULL); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| |
| if (ret != 0) { |
| if (path->slots[0] == 0) |
| goto not_found; |
| path->slots[0]--; |
| } |
| |
| leaf = path->nodes[0]; |
| item = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| /* are we inside the extent that was found? */ |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| found_type = btrfs_key_type(&found_key); |
| if (found_key.objectid != objectid || |
| found_type != BTRFS_EXTENT_DATA_KEY) { |
| goto not_found; |
| } |
| |
| found_type = btrfs_file_extent_type(leaf, item); |
| extent_start = found_key.offset; |
| compress_type = btrfs_file_extent_compression(leaf, item); |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| extent_end = extent_start + |
| btrfs_file_extent_num_bytes(leaf, item); |
| } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { |
| size_t size; |
| size = btrfs_file_extent_inline_len(leaf, item); |
| extent_end = (extent_start + size + root->sectorsize - 1) & |
| ~((u64)root->sectorsize - 1); |
| } |
| |
| if (start >= extent_end) { |
| path->slots[0]++; |
| if (path->slots[0] >= btrfs_header_nritems(leaf)) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret < 0) { |
| err = ret; |
| goto out; |
| } |
| if (ret > 0) |
| goto not_found; |
| leaf = path->nodes[0]; |
| } |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| if (found_key.objectid != objectid || |
| found_key.type != BTRFS_EXTENT_DATA_KEY) |
| goto not_found; |
| if (start + len <= found_key.offset) |
| goto not_found; |
| em->start = start; |
| em->len = found_key.offset - start; |
| goto not_found_em; |
| } |
| |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| em->start = extent_start; |
| em->len = extent_end - extent_start; |
| em->orig_start = extent_start - |
| btrfs_file_extent_offset(leaf, item); |
| bytenr = btrfs_file_extent_disk_bytenr(leaf, item); |
| if (bytenr == 0) { |
| em->block_start = EXTENT_MAP_HOLE; |
| goto insert; |
| } |
| if (compress_type != BTRFS_COMPRESS_NONE) { |
| set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
| em->compress_type = compress_type; |
| em->block_start = bytenr; |
| em->block_len = btrfs_file_extent_disk_num_bytes(leaf, |
| item); |
| } else { |
| bytenr += btrfs_file_extent_offset(leaf, item); |
| em->block_start = bytenr; |
| em->block_len = em->len; |
| if (found_type == BTRFS_FILE_EXTENT_PREALLOC) |
| set_bit(EXTENT_FLAG_PREALLOC, &em->flags); |
| } |
| goto insert; |
| } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { |
| unsigned long ptr; |
| char *map; |
| size_t size; |
| size_t extent_offset; |
| size_t copy_size; |
| |
| em->block_start = EXTENT_MAP_INLINE; |
| if (!page || create) { |
| em->start = extent_start; |
| em->len = extent_end - extent_start; |
| goto out; |
| } |
| |
| size = btrfs_file_extent_inline_len(leaf, item); |
| extent_offset = page_offset(page) + pg_offset - extent_start; |
| copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset, |
| size - extent_offset); |
| em->start = extent_start + extent_offset; |
| em->len = (copy_size + root->sectorsize - 1) & |
| ~((u64)root->sectorsize - 1); |
| em->orig_start = EXTENT_MAP_INLINE; |
| if (compress_type) { |
| set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); |
| em->compress_type = compress_type; |
| } |
| ptr = btrfs_file_extent_inline_start(item) + extent_offset; |
| if (create == 0 && !PageUptodate(page)) { |
| if (btrfs_file_extent_compression(leaf, item) != |
| BTRFS_COMPRESS_NONE) { |
| ret = uncompress_inline(path, inode, page, |
| pg_offset, |
| extent_offset, item); |
| BUG_ON(ret); /* -ENOMEM */ |
| } else { |
| map = kmap(page); |
| read_extent_buffer(leaf, map + pg_offset, ptr, |
| copy_size); |
| if (pg_offset + copy_size < PAGE_CACHE_SIZE) { |
| memset(map + pg_offset + copy_size, 0, |
| PAGE_CACHE_SIZE - pg_offset - |
| copy_size); |
| } |
| kunmap(page); |
| } |
| flush_dcache_page(page); |
| } else if (create && PageUptodate(page)) { |
| BUG(); |
| if (!trans) { |
| kunmap(page); |
| free_extent_map(em); |
| em = NULL; |
| |
| btrfs_release_path(path); |
| trans = btrfs_join_transaction(root); |
| |
| if (IS_ERR(trans)) |
| return ERR_CAST(trans); |
| goto again; |
| } |
| map = kmap(page); |
| write_extent_buffer(leaf, map + pg_offset, ptr, |
| copy_size); |
| kunmap(page); |
| btrfs_mark_buffer_dirty(leaf); |
| } |
| set_extent_uptodate(io_tree, em->start, |
| extent_map_end(em) - 1, NULL, GFP_NOFS); |
| goto insert; |
| } else { |
| printk(KERN_ERR "btrfs unknown found_type %d\n", found_type); |
| WARN_ON(1); |
| } |
| not_found: |
| em->start = start; |
| em->len = len; |
| not_found_em: |
| em->block_start = EXTENT_MAP_HOLE; |
| set_bit(EXTENT_FLAG_VACANCY, &em->flags); |
| insert: |
| btrfs_release_path(path); |
| if (em->start > start || extent_map_end(em) <= start) { |
| printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed " |
| "[%llu %llu]\n", (unsigned long long)em->start, |
| (unsigned long long)em->len, |
| (unsigned long long)start, |
| (unsigned long long)len); |
| err = -EIO; |
| goto out; |
| } |
| |
| err = 0; |
| write_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| /* it is possible that someone inserted the extent into the tree |
| * while we had the lock dropped. It is also possible that |
| * an overlapping map exists in the tree |
| */ |
| if (ret == -EEXIST) { |
| struct extent_map *existing; |
| |
| ret = 0; |
| |
| existing = lookup_extent_mapping(em_tree, start, len); |
| if (existing && (existing->start > start || |
| existing->start + existing->len <= start)) { |
| free_extent_map(existing); |
| existing = NULL; |
| } |
| if (!existing) { |
| existing = lookup_extent_mapping(em_tree, em->start, |
| em->len); |
| if (existing) { |
| err = merge_extent_mapping(em_tree, existing, |
| em, start, |
| root->sectorsize); |
| free_extent_map(existing); |
| if (err) { |
| free_extent_map(em); |
| em = NULL; |
| } |
| } else { |
| err = -EIO; |
| free_extent_map(em); |
| em = NULL; |
| } |
| } else { |
| free_extent_map(em); |
| em = existing; |
| err = 0; |
| } |
| } |
| write_unlock(&em_tree->lock); |
| out: |
| |
| trace_btrfs_get_extent(root, em); |
| |
| if (path) |
| btrfs_free_path(path); |
| if (trans) { |
| ret = btrfs_end_transaction(trans, root); |
| if (!err) |
| err = ret; |
| } |
| if (err) { |
| free_extent_map(em); |
| return ERR_PTR(err); |
| } |
| BUG_ON(!em); /* Error is always set */ |
| return em; |
| } |
| |
| struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page, |
| size_t pg_offset, u64 start, u64 len, |
| int create) |
| { |
| struct extent_map *em; |
| struct extent_map *hole_em = NULL; |
| u64 range_start = start; |
| u64 end; |
| u64 found; |
| u64 found_end; |
| int err = 0; |
| |
| em = btrfs_get_extent(inode, page, pg_offset, start, len, create); |
| if (IS_ERR(em)) |
| return em; |
| if (em) { |
| /* |
| * if our em maps to a hole, there might |
| * actually be delalloc bytes behind it |
| */ |
| if (em->block_start != EXTENT_MAP_HOLE) |
| return em; |
| else |
| hole_em = em; |
| } |
| |
| /* check to see if we've wrapped (len == -1 or similar) */ |
| end = start + len; |
| if (end < start) |
| end = (u64)-1; |
| else |
| end -= 1; |
| |
| em = NULL; |
| |
| /* ok, we didn't find anything, lets look for delalloc */ |
| found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start, |
| end, len, EXTENT_DELALLOC, 1); |
| found_end = range_start + found; |
| if (found_end < range_start) |
| found_end = (u64)-1; |
| |
| /* |
| * we didn't find anything useful, return |
| * the original results from get_extent() |
| */ |
| if (range_start > end || found_end <= start) { |
| em = hole_em; |
| hole_em = NULL; |
| goto out; |
| } |
| |
| /* adjust the range_start to make sure it doesn't |
| * go backwards from the start they passed in |
| */ |
| range_start = max(start,range_start); |
| found = found_end - range_start; |
| |
| if (found > 0) { |
| u64 hole_start = start; |
| u64 hole_len = len; |
| |
| em = alloc_extent_map(); |
| if (!em) { |
| err = -ENOMEM; |
| goto out; |
| } |
| /* |
| * when btrfs_get_extent can't find anything it |
| * returns one huge hole |
| * |
| * make sure what it found really fits our range, and |
| * adjust to make sure it is based on the start from |
| * the caller |
| */ |
| if (hole_em) { |
| u64 calc_end = extent_map_end(hole_em); |
| |
| if (calc_end <= start || (hole_em->start > end)) { |
| free_extent_map(hole_em); |
| hole_em = NULL; |
| } else { |
| hole_start = max(hole_em->start, start); |
| hole_len = calc_end - hole_start; |
| } |
| } |
| em->bdev = NULL; |
| if (hole_em && range_start > hole_start) { |
| /* our hole starts before our delalloc, so we |
| * have to return just the parts of the hole |
| * that go until the delalloc starts |
| */ |
| em->len = min(hole_len, |
| range_start - hole_start); |
| em->start = hole_start; |
| em->orig_start = hole_start; |
| /* |
| * don't adjust block start at all, |
| * it is fixed at EXTENT_MAP_HOLE |
| */ |
| em->block_start = hole_em->block_start; |
| em->block_len = hole_len; |
| } else { |
| em->start = range_start; |
| em->len = found; |
| em->orig_start = range_start; |
| em->block_start = EXTENT_MAP_DELALLOC; |
| em->block_len = found; |
| } |
| } else if (hole_em) { |
| return hole_em; |
| } |
| out: |
| |
| free_extent_map(hole_em); |
| if (err) { |
| free_extent_map(em); |
| return ERR_PTR(err); |
| } |
| return em; |
| } |
| |
| static struct extent_map *btrfs_new_extent_direct(struct inode *inode, |
| struct extent_map *em, |
| u64 start, u64 len) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct btrfs_key ins; |
| u64 alloc_hint; |
| int ret; |
| bool insert = false; |
| |
| /* |
| * Ok if the extent map we looked up is a hole and is for the exact |
| * range we want, there is no reason to allocate a new one, however if |
| * it is not right then we need to free this one and drop the cache for |
| * our range. |
| */ |
| if (em->block_start != EXTENT_MAP_HOLE || em->start != start || |
| em->len != len) { |
| free_extent_map(em); |
| em = NULL; |
| insert = true; |
| btrfs_drop_extent_cache(inode, start, start + len - 1, 0); |
| } |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) |
| return ERR_CAST(trans); |
| |
| if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024) |
| btrfs_add_inode_defrag(trans, inode); |
| |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| alloc_hint = get_extent_allocation_hint(inode, start, len); |
| ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0, |
| alloc_hint, &ins, 1); |
| if (ret) { |
| em = ERR_PTR(ret); |
| goto out; |
| } |
| |
| if (!em) { |
| em = alloc_extent_map(); |
| if (!em) { |
| em = ERR_PTR(-ENOMEM); |
| goto out; |
| } |
| } |
| |
| em->start = start; |
| em->orig_start = em->start; |
| em->len = ins.offset; |
| |
| em->block_start = ins.objectid; |
| em->block_len = ins.offset; |
| em->bdev = root->fs_info->fs_devices->latest_bdev; |
| |
| /* |
| * We need to do this because if we're using the original em we searched |
| * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that. |
| */ |
| em->flags = 0; |
| set_bit(EXTENT_FLAG_PINNED, &em->flags); |
| |
| while (insert) { |
| write_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| write_unlock(&em_tree->lock); |
| if (ret != -EEXIST) |
| break; |
| btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0); |
| } |
| |
| ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid, |
| ins.offset, ins.offset, 0); |
| if (ret) { |
| btrfs_free_reserved_extent(root, ins.objectid, ins.offset); |
| em = ERR_PTR(ret); |
| } |
| out: |
| btrfs_end_transaction(trans, root); |
| return em; |
| } |
| |
| /* |
| * returns 1 when the nocow is safe, < 1 on error, 0 if the |
| * block must be cow'd |
| */ |
| static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans, |
| struct inode *inode, u64 offset, u64 len) |
| { |
| struct btrfs_path *path; |
| int ret; |
| struct extent_buffer *leaf; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_file_extent_item *fi; |
| struct btrfs_key key; |
| u64 disk_bytenr; |
| u64 backref_offset; |
| u64 extent_end; |
| u64 num_bytes; |
| int slot; |
| int found_type; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode), |
| offset, 0); |
| if (ret < 0) |
| goto out; |
| |
| slot = path->slots[0]; |
| if (ret == 1) { |
| if (slot == 0) { |
| /* can't find the item, must cow */ |
| ret = 0; |
| goto out; |
| } |
| slot--; |
| } |
| ret = 0; |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &key, slot); |
| if (key.objectid != btrfs_ino(inode) || |
| key.type != BTRFS_EXTENT_DATA_KEY) { |
| /* not our file or wrong item type, must cow */ |
| goto out; |
| } |
| |
| if (key.offset > offset) { |
| /* Wrong offset, must cow */ |
| goto out; |
| } |
| |
| fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); |
| found_type = btrfs_file_extent_type(leaf, fi); |
| if (found_type != BTRFS_FILE_EXTENT_REG && |
| found_type != BTRFS_FILE_EXTENT_PREALLOC) { |
| /* not a regular extent, must cow */ |
| goto out; |
| } |
| disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); |
| backref_offset = btrfs_file_extent_offset(leaf, fi); |
| |
| extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); |
| if (extent_end < offset + len) { |
| /* extent doesn't include our full range, must cow */ |
| goto out; |
| } |
| |
| if (btrfs_extent_readonly(root, disk_bytenr)) |
| goto out; |
| |
| /* |
| * look for other files referencing this extent, if we |
| * find any we must cow |
| */ |
| if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode), |
| key.offset - backref_offset, disk_bytenr)) |
| goto out; |
| |
| /* |
| * adjust disk_bytenr and num_bytes to cover just the bytes |
| * in this extent we are about to write. If there |
| * are any csums in that range we have to cow in order |
| * to keep the csums correct |
| */ |
| disk_bytenr += backref_offset; |
| disk_bytenr += offset - key.offset; |
| num_bytes = min(offset + len, extent_end) - offset; |
| if (csum_exist_in_range(root, disk_bytenr, num_bytes)) |
| goto out; |
| /* |
| * all of the above have passed, it is safe to overwrite this extent |
| * without cow |
| */ |
| ret = 1; |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock, |
| struct buffer_head *bh_result, int create) |
| { |
| struct extent_map *em; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 start = iblock << inode->i_blkbits; |
| u64 len = bh_result->b_size; |
| struct btrfs_trans_handle *trans; |
| |
| em = btrfs_get_extent(inode, NULL, 0, start, len, 0); |
| if (IS_ERR(em)) |
| return PTR_ERR(em); |
| |
| /* |
| * Ok for INLINE and COMPRESSED extents we need to fallback on buffered |
| * io. INLINE is special, and we could probably kludge it in here, but |
| * it's still buffered so for safety lets just fall back to the generic |
| * buffered path. |
| * |
| * For COMPRESSED we _have_ to read the entire extent in so we can |
| * decompress it, so there will be buffering required no matter what we |
| * do, so go ahead and fallback to buffered. |
| * |
| * We return -ENOTBLK because thats what makes DIO go ahead and go back |
| * to buffered IO. Don't blame me, this is the price we pay for using |
| * the generic code. |
| */ |
| if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) || |
| em->block_start == EXTENT_MAP_INLINE) { |
| free_extent_map(em); |
| return -ENOTBLK; |
| } |
| |
| /* Just a good old fashioned hole, return */ |
| if (!create && (em->block_start == EXTENT_MAP_HOLE || |
| test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { |
| free_extent_map(em); |
| /* DIO will do one hole at a time, so just unlock a sector */ |
| unlock_extent(&BTRFS_I(inode)->io_tree, start, |
| start + root->sectorsize - 1); |
| return 0; |
| } |
| |
| /* |
| * We don't allocate a new extent in the following cases |
| * |
| * 1) The inode is marked as NODATACOW. In this case we'll just use the |
| * existing extent. |
| * 2) The extent is marked as PREALLOC. We're good to go here and can |
| * just use the extent. |
| * |
| */ |
| if (!create) { |
| len = em->len - (start - em->start); |
| goto map; |
| } |
| |
| if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) || |
| ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) && |
| em->block_start != EXTENT_MAP_HOLE)) { |
| int type; |
| int ret; |
| u64 block_start; |
| |
| if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
| type = BTRFS_ORDERED_PREALLOC; |
| else |
| type = BTRFS_ORDERED_NOCOW; |
| len = min(len, em->len - (start - em->start)); |
| block_start = em->block_start + (start - em->start); |
| |
| /* |
| * we're not going to log anything, but we do need |
| * to make sure the current transaction stays open |
| * while we look for nocow cross refs |
| */ |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) |
| goto must_cow; |
| |
| if (can_nocow_odirect(trans, inode, start, len) == 1) { |
| ret = btrfs_add_ordered_extent_dio(inode, start, |
| block_start, len, len, type); |
| btrfs_end_transaction(trans, root); |
| if (ret) { |
| free_extent_map(em); |
| return ret; |
| } |
| goto unlock; |
| } |
| btrfs_end_transaction(trans, root); |
| } |
| must_cow: |
| /* |
| * this will cow the extent, reset the len in case we changed |
| * it above |
| */ |
| len = bh_result->b_size; |
| em = btrfs_new_extent_direct(inode, em, start, len); |
| if (IS_ERR(em)) |
| return PTR_ERR(em); |
| len = min(len, em->len - (start - em->start)); |
| unlock: |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1, |
| EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1, |
| 0, NULL, GFP_NOFS); |
| map: |
| bh_result->b_blocknr = (em->block_start + (start - em->start)) >> |
| inode->i_blkbits; |
| bh_result->b_size = len; |
| bh_result->b_bdev = em->bdev; |
| set_buffer_mapped(bh_result); |
| if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) |
| set_buffer_new(bh_result); |
| |
| free_extent_map(em); |
| |
| return 0; |
| } |
| |
| struct btrfs_dio_private { |
| struct inode *inode; |
| u64 logical_offset; |
| u64 disk_bytenr; |
| u64 bytes; |
| u32 *csums; |
| void *private; |
| |
| /* number of bios pending for this dio */ |
| atomic_t pending_bios; |
| |
| /* IO errors */ |
| int errors; |
| |
| struct bio *orig_bio; |
| }; |
| |
| static void btrfs_endio_direct_read(struct bio *bio, int err) |
| { |
| struct btrfs_dio_private *dip = bio->bi_private; |
| struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1; |
| struct bio_vec *bvec = bio->bi_io_vec; |
| struct inode *inode = dip->inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 start; |
| u32 *private = dip->csums; |
| |
| start = dip->logical_offset; |
| do { |
| if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { |
| struct page *page = bvec->bv_page; |
| char *kaddr; |
| u32 csum = ~(u32)0; |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| kaddr = kmap_atomic(page); |
| csum = btrfs_csum_data(root, kaddr + bvec->bv_offset, |
| csum, bvec->bv_len); |
| btrfs_csum_final(csum, (char *)&csum); |
| kunmap_atomic(kaddr); |
| local_irq_restore(flags); |
| |
| flush_dcache_page(bvec->bv_page); |
| if (csum != *private) { |
| printk(KERN_ERR "btrfs csum failed ino %llu off" |
| " %llu csum %u private %u\n", |
| (unsigned long long)btrfs_ino(inode), |
| (unsigned long long)start, |
| csum, *private); |
| err = -EIO; |
| } |
| } |
| |
| start += bvec->bv_len; |
| private++; |
| bvec++; |
| } while (bvec <= bvec_end); |
| |
| unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset, |
| dip->logical_offset + dip->bytes - 1); |
| bio->bi_private = dip->private; |
| |
| kfree(dip->csums); |
| kfree(dip); |
| |
| /* If we had a csum failure make sure to clear the uptodate flag */ |
| if (err) |
| clear_bit(BIO_UPTODATE, &bio->bi_flags); |
| dio_end_io(bio, err); |
| } |
| |
| static void btrfs_endio_direct_write(struct bio *bio, int err) |
| { |
| struct btrfs_dio_private *dip = bio->bi_private; |
| struct inode *inode = dip->inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_ordered_extent *ordered = NULL; |
| struct extent_state *cached_state = NULL; |
| u64 ordered_offset = dip->logical_offset; |
| u64 ordered_bytes = dip->bytes; |
| int ret; |
| |
| if (err) |
| goto out_done; |
| again: |
| ret = btrfs_dec_test_first_ordered_pending(inode, &ordered, |
| &ordered_offset, |
| ordered_bytes); |
| if (!ret) |
| goto out_test; |
| |
| BUG_ON(!ordered); |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| err = -ENOMEM; |
| goto out; |
| } |
| trans->block_rsv = &root->fs_info->delalloc_block_rsv; |
| |
| if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) { |
| ret = btrfs_ordered_update_i_size(inode, 0, ordered); |
| if (!ret) |
| err = btrfs_update_inode_fallback(trans, root, inode); |
| goto out; |
| } |
| |
| lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset, |
| ordered->file_offset + ordered->len - 1, 0, |
| &cached_state); |
| |
| if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) { |
| ret = btrfs_mark_extent_written(trans, inode, |
| ordered->file_offset, |
| ordered->file_offset + |
| ordered->len); |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| } else { |
| ret = insert_reserved_file_extent(trans, inode, |
| ordered->file_offset, |
| ordered->start, |
| ordered->disk_len, |
| ordered->len, |
| ordered->len, |
| 0, 0, 0, |
| BTRFS_FILE_EXTENT_REG); |
| unpin_extent_cache(&BTRFS_I(inode)->extent_tree, |
| ordered->file_offset, ordered->len); |
| if (ret) { |
| err = ret; |
| WARN_ON(1); |
| goto out_unlock; |
| } |
| } |
| |
| add_pending_csums(trans, inode, ordered->file_offset, &ordered->list); |
| ret = btrfs_ordered_update_i_size(inode, 0, ordered); |
| if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) |
| btrfs_update_inode_fallback(trans, root, inode); |
| ret = 0; |
| out_unlock: |
| unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset, |
| ordered->file_offset + ordered->len - 1, |
| &cached_state, GFP_NOFS); |
| out: |
| btrfs_delalloc_release_metadata(inode, ordered->len); |
| btrfs_end_transaction(trans, root); |
| ordered_offset = ordered->file_offset + ordered->len; |
| btrfs_put_ordered_extent(ordered); |
| btrfs_put_ordered_extent(ordered); |
| |
| out_test: |
| /* |
| * our bio might span multiple ordered extents. If we haven't |
| * completed the accounting for the whole dio, go back and try again |
| */ |
| if (ordered_offset < dip->logical_offset + dip->bytes) { |
| ordered_bytes = dip->logical_offset + dip->bytes - |
| ordered_offset; |
| goto again; |
| } |
| out_done: |
| bio->bi_private = dip->private; |
| |
| kfree(dip->csums); |
| kfree(dip); |
| |
| /* If we had an error make sure to clear the uptodate flag */ |
| if (err) |
| clear_bit(BIO_UPTODATE, &bio->bi_flags); |
| dio_end_io(bio, err); |
| } |
| |
| static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw, |
| struct bio *bio, int mirror_num, |
| unsigned long bio_flags, u64 offset) |
| { |
| int ret; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| ret = btrfs_csum_one_bio(root, inode, bio, offset, 1); |
| BUG_ON(ret); /* -ENOMEM */ |
| return 0; |
| } |
| |
| static void btrfs_end_dio_bio(struct bio *bio, int err) |
| { |
| struct btrfs_dio_private *dip = bio->bi_private; |
| |
| if (err) { |
| printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu " |
| "sector %#Lx len %u err no %d\n", |
| (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw, |
| (unsigned long long)bio->bi_sector, bio->bi_size, err); |
| dip->errors = 1; |
| |
| /* |
| * before atomic variable goto zero, we must make sure |
| * dip->errors is perceived to be set. |
| */ |
| smp_mb__before_atomic_dec(); |
| } |
| |
| /* if there are more bios still pending for this dio, just exit */ |
| if (!atomic_dec_and_test(&dip->pending_bios)) |
| goto out; |
| |
| if (dip->errors) |
| bio_io_error(dip->orig_bio); |
| else { |
| set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags); |
| bio_endio(dip->orig_bio, 0); |
| } |
| out: |
| bio_put(bio); |
| } |
| |
| static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev, |
| u64 first_sector, gfp_t gfp_flags) |
| { |
| int nr_vecs = bio_get_nr_vecs(bdev); |
| return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags); |
| } |
| |
| static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode, |
| int rw, u64 file_offset, int skip_sum, |
| u32 *csums, int async_submit) |
| { |
| int write = rw & REQ_WRITE; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int ret; |
| |
| bio_get(bio); |
| ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0); |
| if (ret) |
| goto err; |
| |
| if (skip_sum) |
| goto map; |
| |
| if (write && async_submit) { |
| ret = btrfs_wq_submit_bio(root->fs_info, |
| inode, rw, bio, 0, 0, |
| file_offset, |
| __btrfs_submit_bio_start_direct_io, |
| __btrfs_submit_bio_done); |
| goto err; |
| } else if (write) { |
| /* |
| * If we aren't doing async submit, calculate the csum of the |
| * bio now. |
| */ |
| ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1); |
| if (ret) |
| goto err; |
| } else if (!skip_sum) { |
| ret = btrfs_lookup_bio_sums_dio(root, inode, bio, |
| file_offset, csums); |
| if (ret) |
| goto err; |
| } |
| |
| map: |
| ret = btrfs_map_bio(root, rw, bio, 0, async_submit); |
| err: |
| bio_put(bio); |
| return ret; |
| } |
| |
| static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, |
| int skip_sum) |
| { |
| struct inode *inode = dip->inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; |
| struct bio *bio; |
| struct bio *orig_bio = dip->orig_bio; |
| struct bio_vec *bvec = orig_bio->bi_io_vec; |
| u64 start_sector = orig_bio->bi_sector; |
| u64 file_offset = dip->logical_offset; |
| u64 submit_len = 0; |
| u64 map_length; |
| int nr_pages = 0; |
| u32 *csums = dip->csums; |
| int ret = 0; |
| int async_submit = 0; |
| int write = rw & REQ_WRITE; |
| |
| map_length = orig_bio->bi_size; |
| ret = btrfs_map_block(map_tree, READ, start_sector << 9, |
| &map_length, NULL, 0); |
| if (ret) { |
| bio_put(orig_bio); |
| return -EIO; |
| } |
| |
| if (map_length >= orig_bio->bi_size) { |
| bio = orig_bio; |
| goto submit; |
| } |
| |
| async_submit = 1; |
| bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS); |
| if (!bio) |
| return -ENOMEM; |
| bio->bi_private = dip; |
| bio->bi_end_io = btrfs_end_dio_bio; |
| atomic_inc(&dip->pending_bios); |
| |
| while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) { |
| if (unlikely(map_length < submit_len + bvec->bv_len || |
| bio_add_page(bio, bvec->bv_page, bvec->bv_len, |
| bvec->bv_offset) < bvec->bv_len)) { |
| /* |
| * inc the count before we submit the bio so |
| * we know the end IO handler won't happen before |
| * we inc the count. Otherwise, the dip might get freed |
| * before we're done setting it up |
| */ |
| atomic_inc(&dip->pending_bios); |
| ret = __btrfs_submit_dio_bio(bio, inode, rw, |
| file_offset, skip_sum, |
| csums, async_submit); |
| if (ret) { |
| bio_put(bio); |
| atomic_dec(&dip->pending_bios); |
| goto out_err; |
| } |
| |
| /* Write's use the ordered csums */ |
| if (!write && !skip_sum) |
| csums = csums + nr_pages; |
| start_sector += submit_len >> 9; |
| file_offset += submit_len; |
| |
| submit_len = 0; |
| nr_pages = 0; |
| |
| bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, |
| start_sector, GFP_NOFS); |
| if (!bio) |
| goto out_err; |
| bio->bi_private = dip; |
| bio->bi_end_io = btrfs_end_dio_bio; |
| |
| map_length = orig_bio->bi_size; |
| ret = btrfs_map_block(map_tree, READ, start_sector << 9, |
| &map_length, NULL, 0); |
| if (ret) { |
| bio_put(bio); |
| goto out_err; |
| } |
| } else { |
| submit_len += bvec->bv_len; |
| nr_pages ++; |
| bvec++; |
| } |
| } |
| |
| submit: |
| ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum, |
| csums, async_submit); |
| if (!ret) |
| return 0; |
| |
| bio_put(bio); |
| out_err: |
| dip->errors = 1; |
| /* |
| * before atomic variable goto zero, we must |
| * make sure dip->errors is perceived to be set. |
| */ |
| smp_mb__before_atomic_dec(); |
| if (atomic_dec_and_test(&dip->pending_bios)) |
| bio_io_error(dip->orig_bio); |
| |
| /* bio_end_io() will handle error, so we needn't return it */ |
| return 0; |
| } |
| |
| static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode, |
| loff_t file_offset) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_dio_private *dip; |
| struct bio_vec *bvec = bio->bi_io_vec; |
| int skip_sum; |
| int write = rw & REQ_WRITE; |
| int ret = 0; |
| |
| skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; |
| |
| dip = kmalloc(sizeof(*dip), GFP_NOFS); |
| if (!dip) { |
| ret = -ENOMEM; |
| goto free_ordered; |
| } |
| dip->csums = NULL; |
| |
| /* Write's use the ordered csum stuff, so we don't need dip->csums */ |
| if (!write && !skip_sum) { |
| dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS); |
| if (!dip->csums) { |
| kfree(dip); |
| ret = -ENOMEM; |
| goto free_ordered; |
| } |
| } |
| |
| dip->private = bio->bi_private; |
| dip->inode = inode; |
| dip->logical_offset = file_offset; |
| |
| dip->bytes = 0; |
| do { |
| dip->bytes += bvec->bv_len; |
| bvec++; |
| } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1)); |
| |
| dip->disk_bytenr = (u64)bio->bi_sector << 9; |
| bio->bi_private = dip; |
| dip->errors = 0; |
| dip->orig_bio = bio; |
| atomic_set(&dip->pending_bios, 0); |
| |
| if (write) |
| bio->bi_end_io = btrfs_endio_direct_write; |
| else |
| bio->bi_end_io = btrfs_endio_direct_read; |
| |
| ret = btrfs_submit_direct_hook(rw, dip, skip_sum); |
| if (!ret) |
| return; |
| free_ordered: |
| /* |
| * If this is a write, we need to clean up the reserved space and kill |
| * the ordered extent. |
| */ |
| if (write) { |
| struct btrfs_ordered_extent *ordered; |
| ordered = btrfs_lookup_ordered_extent(inode, file_offset); |
| if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) && |
| !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) |
| btrfs_free_reserved_extent(root, ordered->start, |
| ordered->disk_len); |
| btrfs_put_ordered_extent(ordered); |
| btrfs_put_ordered_extent(ordered); |
| } |
| bio_endio(bio, ret); |
| } |
| |
| static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb, |
| const struct iovec *iov, loff_t offset, |
| unsigned long nr_segs) |
| { |
| int seg; |
| int i; |
| size_t size; |
| unsigned long addr; |
| unsigned blocksize_mask = root->sectorsize - 1; |
| ssize_t retval = -EINVAL; |
| loff_t end = offset; |
| |
| if (offset & blocksize_mask) |
| goto out; |
| |
| /* Check the memory alignment. Blocks cannot straddle pages */ |
| for (seg = 0; seg < nr_segs; seg++) { |
| addr = (unsigned long)iov[seg].iov_base; |
| size = iov[seg].iov_len; |
| end += size; |
| if ((addr & blocksize_mask) || (size & blocksize_mask)) |
| goto out; |
| |
| /* If this is a write we don't need to check anymore */ |
| if (rw & WRITE) |
| continue; |
| |
| /* |
| * Check to make sure we don't have duplicate iov_base's in this |
| * iovec, if so return EINVAL, otherwise we'll get csum errors |
| * when reading back. |
| */ |
| for (i = seg + 1; i < nr_segs; i++) { |
| if (iov[seg].iov_base == iov[i].iov_base) |
| goto out; |
| } |
| } |
| retval = 0; |
| out: |
| return retval; |
| } |
| static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb, |
| const struct iovec *iov, loff_t offset, |
| unsigned long nr_segs) |
| { |
| struct file *file = iocb->ki_filp; |
| struct inode *inode = file->f_mapping->host; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| u64 lockstart, lockend; |
| ssize_t ret; |
| int writing = rw & WRITE; |
| int write_bits = 0; |
| size_t count = iov_length(iov, nr_segs); |
| |
| if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov, |
| offset, nr_segs)) { |
| return 0; |
| } |
| |
| lockstart = offset; |
| lockend = offset + count - 1; |
| |
| if (writing) { |
| ret = btrfs_delalloc_reserve_space(inode, count); |
| if (ret) |
| goto out; |
| } |
| |
| while (1) { |
| lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, |
| 0, &cached_state); |
| /* |
| * We're concerned with the entire range that we're going to be |
| * doing DIO to, so we need to make sure theres no ordered |
| * extents in this range. |
| */ |
| ordered = btrfs_lookup_ordered_range(inode, lockstart, |
| lockend - lockstart + 1); |
| if (!ordered) |
| break; |
| unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, |
| &cached_state, GFP_NOFS); |
| btrfs_start_ordered_extent(inode, ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| cond_resched(); |
| } |
| |
| /* |
| * we don't use btrfs_set_extent_delalloc because we don't want |
| * the dirty or uptodate bits |
| */ |
| if (writing) { |
| write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING; |
| ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, |
| EXTENT_DELALLOC, NULL, &cached_state, |
| GFP_NOFS); |
| if (ret) { |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, |
| lockend, EXTENT_LOCKED | write_bits, |
| 1, 0, &cached_state, GFP_NOFS); |
| goto out; |
| } |
| } |
| |
| free_extent_state(cached_state); |
| cached_state = NULL; |
| |
| ret = __blockdev_direct_IO(rw, iocb, inode, |
| BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev, |
| iov, offset, nr_segs, btrfs_get_blocks_direct, NULL, |
| btrfs_submit_direct, 0); |
| |
| if (ret < 0 && ret != -EIOCBQUEUED) { |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, offset, |
| offset + iov_length(iov, nr_segs) - 1, |
| EXTENT_LOCKED | write_bits, 1, 0, |
| &cached_state, GFP_NOFS); |
| } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) { |
| /* |
| * We're falling back to buffered, unlock the section we didn't |
| * do IO on. |
| */ |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret, |
| offset + iov_length(iov, nr_segs) - 1, |
| EXTENT_LOCKED | write_bits, 1, 0, |
| &cached_state, GFP_NOFS); |
| } |
| out: |
| free_extent_state(cached_state); |
| return ret; |
| } |
| |
| static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, |
| __u64 start, __u64 len) |
| { |
| return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap); |
| } |
| |
| int btrfs_readpage(struct file *file, struct page *page) |
| { |
| struct extent_io_tree *tree; |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| return extent_read_full_page(tree, page, btrfs_get_extent, 0); |
| } |
| |
| static int btrfs_writepage(struct page *page, struct writeback_control *wbc) |
| { |
| struct extent_io_tree *tree; |
| |
| |
| if (current->flags & PF_MEMALLOC) { |
| redirty_page_for_writepage(wbc, page); |
| unlock_page(page); |
| return 0; |
| } |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| return extent_write_full_page(tree, page, btrfs_get_extent, wbc); |
| } |
| |
| int btrfs_writepages(struct address_space *mapping, |
| struct writeback_control *wbc) |
| { |
| struct extent_io_tree *tree; |
| |
| tree = &BTRFS_I(mapping->host)->io_tree; |
| return extent_writepages(tree, mapping, btrfs_get_extent, wbc); |
| } |
| |
| static int |
| btrfs_readpages(struct file *file, struct address_space *mapping, |
| struct list_head *pages, unsigned nr_pages) |
| { |
| struct extent_io_tree *tree; |
| tree = &BTRFS_I(mapping->host)->io_tree; |
| return extent_readpages(tree, mapping, pages, nr_pages, |
| btrfs_get_extent); |
| } |
| static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags) |
| { |
| struct extent_io_tree *tree; |
| struct extent_map_tree *map; |
| int ret; |
| |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| map = &BTRFS_I(page->mapping->host)->extent_tree; |
| ret = try_release_extent_mapping(map, tree, page, gfp_flags); |
| if (ret == 1) { |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| page_cache_release(page); |
| } |
| return ret; |
| } |
| |
| static int btrfs_releasepage(struct page *page, gfp_t gfp_flags) |
| { |
| if (PageWriteback(page) || PageDirty(page)) |
| return 0; |
| return __btrfs_releasepage(page, gfp_flags & GFP_NOFS); |
| } |
| |
| static void btrfs_invalidatepage(struct page *page, unsigned long offset) |
| { |
| struct extent_io_tree *tree; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| u64 page_start = page_offset(page); |
| u64 page_end = page_start + PAGE_CACHE_SIZE - 1; |
| |
| |
| /* |
| * we have the page locked, so new writeback can't start, |
| * and the dirty bit won't be cleared while we are here. |
| * |
| * Wait for IO on this page so that we can safely clear |
| * the PagePrivate2 bit and do ordered accounting |
| */ |
| wait_on_page_writeback(page); |
| |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| if (offset) { |
| btrfs_releasepage(page, GFP_NOFS); |
| return; |
| } |
| lock_extent_bits(tree, page_start, page_end, 0, &cached_state); |
| ordered = btrfs_lookup_ordered_extent(page->mapping->host, |
| page_offset(page)); |
| if (ordered) { |
| /* |
| * IO on this page will never be started, so we need |
| * to account for any ordered extents now |
| */ |
| clear_extent_bit(tree, page_start, page_end, |
| EXTENT_DIRTY | EXTENT_DELALLOC | |
| EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0, |
| &cached_state, GFP_NOFS); |
| /* |
| * whoever cleared the private bit is responsible |
| * for the finish_ordered_io |
| */ |
| if (TestClearPagePrivate2(page)) { |
| btrfs_finish_ordered_io(page->mapping->host, |
| page_start, page_end); |
| } |
| btrfs_put_ordered_extent(ordered); |
| cached_state = NULL; |
| lock_extent_bits(tree, page_start, page_end, 0, &cached_state); |
| } |
| clear_extent_bit(tree, page_start, page_end, |
| EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC | |
| EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS); |
| __btrfs_releasepage(page, GFP_NOFS); |
| |
| ClearPageChecked(page); |
| if (PagePrivate(page)) { |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| page_cache_release(page); |
| } |
| } |
| |
| /* |
| * btrfs_page_mkwrite() is not allowed to change the file size as it gets |
| * called from a page fault handler when a page is first dirtied. Hence we must |
| * be careful to check for EOF conditions here. We set the page up correctly |
| * for a written page which means we get ENOSPC checking when writing into |
| * holes and correct delalloc and unwritten extent mapping on filesystems that |
| * support these features. |
| * |
| * We are not allowed to take the i_mutex here so we have to play games to |
| * protect against truncate races as the page could now be beyond EOF. Because |
| * vmtruncate() writes the inode size before removing pages, once we have the |
| * page lock we can determine safely if the page is beyond EOF. If it is not |
| * beyond EOF, then the page is guaranteed safe against truncation until we |
| * unlock the page. |
| */ |
| int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
| { |
| struct page *page = vmf->page; |
| struct inode *inode = fdentry(vma->vm_file)->d_inode; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| char *kaddr; |
| unsigned long zero_start; |
| loff_t size; |
| int ret; |
| int reserved = 0; |
| u64 page_start; |
| u64 page_end; |
| |
| ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); |
| if (!ret) { |
| ret = btrfs_update_time(vma->vm_file); |
| reserved = 1; |
| } |
| if (ret) { |
| if (ret == -ENOMEM) |
| ret = VM_FAULT_OOM; |
| else /* -ENOSPC, -EIO, etc */ |
| ret = VM_FAULT_SIGBUS; |
| if (reserved) |
| goto out; |
| goto out_noreserve; |
| } |
| |
| ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */ |
| again: |
| lock_page(page); |
| size = i_size_read(inode); |
| page_start = page_offset(page); |
| page_end = page_start + PAGE_CACHE_SIZE - 1; |
| |
| if ((page->mapping != inode->i_mapping) || |
| (page_start >= size)) { |
| /* page got truncated out from underneath us */ |
| goto out_unlock; |
| } |
| wait_on_page_writeback(page); |
| |
| lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state); |
| set_page_extent_mapped(page); |
| |
| /* |
| * we can't set the delalloc bits if there are pending ordered |
| * extents. Drop our locks and wait for them to finish |
| */ |
| ordered = btrfs_lookup_ordered_extent(inode, page_start); |
| if (ordered) { |
| unlock_extent_cached(io_tree, page_start, page_end, |
| &cached_state, GFP_NOFS); |
| unlock_page(page); |
| btrfs_start_ordered_extent(inode, ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| goto again; |
| } |
| |
| /* |
| * XXX - page_mkwrite gets called every time the page is dirtied, even |
| * if it was already dirty, so for space accounting reasons we need to |
| * clear any delalloc bits for the range we are fixing to save. There |
| * is probably a better way to do this, but for now keep consistent with |
| * prepare_pages in the normal write path. |
| */ |
| clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end, |
| EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING, |
| 0, 0, &cached_state, GFP_NOFS); |
| |
| ret = btrfs_set_extent_delalloc(inode, page_start, page_end, |
| &cached_state); |
| if (ret) { |
| unlock_extent_cached(io_tree, page_start, page_end, |
| &cached_state, GFP_NOFS); |
| ret = VM_FAULT_SIGBUS; |
| goto out_unlock; |
| } |
| ret = 0; |
| |
| /* page is wholly or partially inside EOF */ |
| if (page_start + PAGE_CACHE_SIZE > size) |
| zero_start = size & ~PAGE_CACHE_MASK; |
| else |
| zero_start = PAGE_CACHE_SIZE; |
| |
| if (zero_start != PAGE_CACHE_SIZE) { |
| kaddr = kmap(page); |
| memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start); |
| flush_dcache_page(page); |
| kunmap(page); |
| } |
| ClearPageChecked(page); |
| set_page_dirty(page); |
| SetPageUptodate(page); |
| |
| BTRFS_I(inode)->last_trans = root->fs_info->generation; |
| BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid; |
| |
| unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS); |
| |
| out_unlock: |
| if (!ret) |
| return VM_FAULT_LOCKED; |
| unlock_page(page); |
| out: |
| btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE); |
| out_noreserve: |
| return ret; |
| } |
| |
| static int btrfs_truncate(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_block_rsv *rsv; |
| int ret; |
| int err = 0; |
| struct btrfs_trans_handle *trans; |
| unsigned long nr; |
| u64 mask = root->sectorsize - 1; |
| u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); |
| |
| ret = btrfs_truncate_page(inode->i_mapping, inode->i_size); |
| if (ret) |
| return ret; |
| |
| btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1); |
| btrfs_ordered_update_i_size(inode, inode->i_size, NULL); |
| |
| /* |
| * Yes ladies and gentelment, this is indeed ugly. The fact is we have |
| * 3 things going on here |
| * |
| * 1) We need to reserve space for our orphan item and the space to |
| * delete our orphan item. Lord knows we don't want to have a dangling |
| * orphan item because we didn't reserve space to remove it. |
| * |
| * 2) We need to reserve space to update our inode. |
| * |
| * 3) We need to have something to cache all the space that is going to |
| * be free'd up by the truncate operation, but also have some slack |
| * space reserved in case it uses space during the truncate (thank you |
| * very much snapshotting). |
| * |
| * And we need these to all be seperate. The fact is we can use alot of |
| * space doing the truncate, and we have no earthly idea how much space |
| * we will use, so we need the truncate reservation to be seperate so it |
| * doesn't end up using space reserved for updating the inode or |
| * removing the orphan item. We also need to be able to stop the |
| * transaction and start a new one, which means we need to be able to |
| * update the inode several times, and we have no idea of knowing how |
| * many times that will be, so we can't just reserve 1 item for the |
| * entirety of the opration, so that has to be done seperately as well. |
| * Then there is the orphan item, which does indeed need to be held on |
| * to for the whole operation, and we need nobody to touch this reserved |
| * space except the orphan code. |
| * |
| * So that leaves us with |
| * |
| * 1) root->orphan_block_rsv - for the orphan deletion. |
| * 2) rsv - for the truncate reservation, which we will steal from the |
| * transaction reservation. |
| * 3) fs_info->trans_block_rsv - this will have 1 items worth left for |
| * updating the inode. |
| */ |
| rsv = btrfs_alloc_block_rsv(root); |
| if (!rsv) |
| return -ENOMEM; |
| rsv->size = min_size; |
| |
| /* |
| * 1 for the truncate slack space |
| * 1 for the orphan item we're going to add |
| * 1 for the orphan item deletion |
| * 1 for updating the inode. |
| */ |
| trans = btrfs_start_transaction(root, 4); |
| if (IS_ERR(trans)) { |
| err = PTR_ERR(trans); |
| goto out; |
| } |
| |
| /* Migrate the slack space for the truncate to our reserve */ |
| ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, |
| min_size); |
| BUG_ON(ret); |
| |
| ret = btrfs_orphan_add(trans, inode); |
| if (ret) { |
| btrfs_end_transaction(trans, root); |
| goto out; |
| } |
| |
| /* |
| * setattr is responsible for setting the ordered_data_close flag, |
| * but that is only tested during the last file release. That |
| * could happen well after the next commit, leaving a great big |
| * window where new writes may get lost if someone chooses to write |
| * to this file after truncating to zero |
| * |
| * The inode doesn't have any dirty data here, and so if we commit |
| * this is a noop. If someone immediately starts writing to the inode |
| * it is very likely we'll catch some of their writes in this |
| * transaction, and the commit will find this file on the ordered |
| * data list with good things to send down. |
| * |
| * This is a best effort solution, there is still a window where |
| * using truncate to replace the contents of the file will |
| * end up with a zero length file after a crash. |
| */ |
| if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close) |
| btrfs_add_ordered_operation(trans, root, inode); |
| |
| while (1) { |
| ret = btrfs_block_rsv_refill(root, rsv, min_size); |
| if (ret) { |
| /* |
| * This can only happen with the original transaction we |
| * started above, every other time we shouldn't have a |
| * transaction started yet. |
| */ |
| if (ret == -EAGAIN) |
| goto end_trans; |
| err = ret; |
| break; |
| } |
| |
| if (!trans) { |
| /* Just need the 1 for updating the inode */ |
| trans = btrfs_start_transaction(root, 1); |
| if (IS_ERR(trans)) { |
| ret = err = PTR_ERR(trans); |
| trans = NULL; |
| break; |
| } |
| } |
| |
| trans->block_rsv = rsv; |
| |
| ret = btrfs_truncate_inode_items(trans, root, inode, |
| inode->i_size, |
| BTRFS_EXTENT_DATA_KEY); |
| if (ret != -EAGAIN) { |
| err = ret; |
| break; |
| } |
| |
| trans->block_rsv = &root->fs_info->trans_block_rsv; |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret) { |
| err = ret; |
| break; |
| } |
| end_trans: |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| trans = NULL; |
| btrfs_btree_balance_dirty(root, nr); |
| } |
| |
| if (ret == 0 && inode->i_nlink > 0) { |
| trans->block_rsv = root->orphan_block_rsv; |
| ret = btrfs_orphan_del(trans, inode); |
| if (ret) |
| err = ret; |
| } else if (ret && inode->i_nlink > 0) { |
| /* |
| * Failed to do the truncate, remove us from the in memory |
| * orphan list. |
| */ |
| ret = btrfs_orphan_del(NULL, inode); |
| } |
| |
| if (trans) { |
| trans->block_rsv = &root->fs_info->trans_block_rsv; |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret && !err) |
| err = ret; |
| |
| nr = trans->blocks_used; |
| ret = btrfs_end_transaction(trans, root); |
| btrfs_btree_balance_dirty(root, nr); |
| } |
| |
| out: |
| btrfs_free_block_rsv(root, rsv); |
| |
| if (ret && !err) |
| err = ret; |
| |
| return err; |
| } |
| |
| /* |
| * create a new subvolume directory/inode (helper for the ioctl). |
| */ |
| int btrfs_create_subvol_root(struct btrfs_trans_handle *trans, |
| struct btrfs_root *new_root, u64 new_dirid) |
| { |
| struct inode *inode; |
| int err; |
| u64 index = 0; |
| |
| inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, |
| new_dirid, new_dirid, |
| S_IFDIR | (~current_umask() & S_IRWXUGO), |
| &index); |
| if (IS_ERR(inode)) |
| return PTR_ERR(inode); |
| inode->i_op = &btrfs_dir_inode_operations; |
| inode->i_fop = &btrfs_dir_file_operations; |
| |
| set_nlink(inode, 1); |
| btrfs_i_size_write(inode, 0); |
| |
| err = btrfs_update_inode(trans, new_root, inode); |
| |
| iput(inode); |
| return err; |
| } |
| |
| struct inode *btrfs_alloc_inode(struct super_block *sb) |
| { |
| struct btrfs_inode *ei; |
| struct inode *inode; |
| |
| ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS); |
| if (!ei) |
| return NULL; |
| |
| ei->root = NULL; |
| ei->space_info = NULL; |
| ei->generation = 0; |
| ei->sequence = 0; |
| ei->last_trans = 0; |
| ei->last_sub_trans = 0; |
| ei->logged_trans = 0; |
| ei->delalloc_bytes = 0; |
| ei->disk_i_size = 0; |
| ei->flags = 0; |
| ei->csum_bytes = 0; |
| ei->index_cnt = (u64)-1; |
| ei->last_unlink_trans = 0; |
| |
| spin_lock_init(&ei->lock); |
| ei->outstanding_extents = 0; |
| ei->reserved_extents = 0; |
| |
| ei->ordered_data_close = 0; |
| ei->orphan_meta_reserved = 0; |
| ei->dummy_inode = 0; |
| ei->in_defrag = 0; |
| ei->delalloc_meta_reserved = 0; |
| ei->force_compress = BTRFS_COMPRESS_NONE; |
| |
| ei->delayed_node = NULL; |
| |
| inode = &ei->vfs_inode; |
| extent_map_tree_init(&ei->extent_tree); |
| extent_io_tree_init(&ei->io_tree, &inode->i_data); |
| extent_io_tree_init(&ei->io_failure_tree, &inode->i_data); |
| ei->io_tree.track_uptodate = 1; |
| ei->io_failure_tree.track_uptodate = 1; |
| mutex_init(&ei->log_mutex); |
| mutex_init(&ei->delalloc_mutex); |
| btrfs_ordered_inode_tree_init(&ei->ordered_tree); |
| INIT_LIST_HEAD(&ei->i_orphan); |
| INIT_LIST_HEAD(&ei->delalloc_inodes); |
| INIT_LIST_HEAD(&ei->ordered_operations); |
| RB_CLEAR_NODE(&ei->rb_node); |
| |
| return inode; |
| } |
| |
| static void btrfs_i_callback(struct rcu_head *head) |
| { |
| struct inode *inode = container_of(head, struct inode, i_rcu); |
| kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode)); |
| } |
| |
| void btrfs_destroy_inode(struct inode *inode) |
| { |
| struct btrfs_ordered_extent *ordered; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| |
| WARN_ON(!list_empty(&inode->i_dentry)); |
| WARN_ON(inode->i_data.nrpages); |
| WARN_ON(BTRFS_I(inode)->outstanding_extents); |
| WARN_ON(BTRFS_I(inode)->reserved_extents); |
| WARN_ON(BTRFS_I(inode)->delalloc_bytes); |
| WARN_ON(BTRFS_I(inode)->csum_bytes); |
| |
| /* |
| * This can happen where we create an inode, but somebody else also |
| * created the same inode and we need to destroy the one we already |
| * created. |
| */ |
| if (!root) |
| goto free; |
| |
| /* |
| * Make sure we're properly removed from the ordered operation |
| * lists. |
| */ |
| smp_mb(); |
| if (!list_empty(&BTRFS_I(inode)->ordered_operations)) { |
| spin_lock(&root->fs_info->ordered_extent_lock); |
| list_del_init(&BTRFS_I(inode)->ordered_operations); |
| spin_unlock(&root->fs_info->ordered_extent_lock); |
| } |
| |
| spin_lock(&root->orphan_lock); |
| if (!list_empty(&BTRFS_I(inode)->i_orphan)) { |
| printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n", |
| (unsigned long long)btrfs_ino(inode)); |
| list_del_init(&BTRFS_I(inode)->i_orphan); |
| } |
| spin_unlock(&root->orphan_lock); |
| |
| while (1) { |
| ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1); |
| if (!ordered) |
| break; |
| else { |
| printk(KERN_ERR "btrfs found ordered " |
| "extent %llu %llu on inode cleanup\n", |
| (unsigned long long)ordered->file_offset, |
| (unsigned long long)ordered->len); |
| btrfs_remove_ordered_extent(inode, ordered); |
| btrfs_put_ordered_extent(ordered); |
| btrfs_put_ordered_extent(ordered); |
| } |
| } |
| inode_tree_del(inode); |
| btrfs_drop_extent_cache(inode, 0, (u64)-1, 0); |
| free: |
| btrfs_remove_delayed_node(inode); |
| call_rcu(&inode->i_rcu, btrfs_i_callback); |
| } |
| |
| int btrfs_drop_inode(struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| |
| if (btrfs_root_refs(&root->root_item) == 0 && |
| !btrfs_is_free_space_inode(root, inode)) |
| return 1; |
| else |
| return generic_drop_inode(inode); |
| } |
| |
| static void init_once(void *foo) |
| { |
| struct btrfs_inode *ei = (struct btrfs_inode *) foo; |
| |
| inode_init_once(&ei->vfs_inode); |
| } |
| |
| void btrfs_destroy_cachep(void) |
| { |
| if (btrfs_inode_cachep) |
| kmem_cache_destroy(btrfs_inode_cachep); |
| if (btrfs_trans_handle_cachep) |
| kmem_cache_destroy(btrfs_trans_handle_cachep); |
| if (btrfs_transaction_cachep) |
| kmem_cache_destroy(btrfs_transaction_cachep); |
| if (btrfs_path_cachep) |
| kmem_cache_destroy(btrfs_path_cachep); |
| if (btrfs_free_space_cachep) |
| kmem_cache_destroy(btrfs_free_space_cachep); |
| } |
| |
| int btrfs_init_cachep(void) |
| { |
| btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache", |
| sizeof(struct btrfs_inode), 0, |
| SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once); |
| if (!btrfs_inode_cachep) |
| goto fail; |
| |
| btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache", |
| sizeof(struct btrfs_trans_handle), 0, |
| SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); |
| if (!btrfs_trans_handle_cachep) |
| goto fail; |
| |
| btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache", |
| sizeof(struct btrfs_transaction), 0, |
| SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); |
| if (!btrfs_transaction_cachep) |
| goto fail; |
| |
| btrfs_path_cachep = kmem_cache_create("btrfs_path_cache", |
| sizeof(struct btrfs_path), 0, |
| SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); |
| if (!btrfs_path_cachep) |
| goto fail; |
| |
| btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache", |
| sizeof(struct btrfs_free_space), 0, |
| SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); |
| if (!btrfs_free_space_cachep) |
| goto fail; |
| |
| return 0; |
| fail: |
| btrfs_destroy_cachep(); |
| return -ENOMEM; |
| } |
| |
| static int btrfs_getattr(struct vfsmount *mnt, |
| struct dentry *dentry, struct kstat *stat) |
| { |
| struct inode *inode = dentry->d_inode; |
| u32 blocksize = inode->i_sb->s_blocksize; |
| |
| generic_fillattr(inode, stat); |
| stat->dev = BTRFS_I(inode)->root->anon_dev; |
| stat->blksize = PAGE_CACHE_SIZE; |
| stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) + |
| ALIGN(BTRFS_I(inode)->delalloc_bytes, blocksize)) >> 9; |
| return 0; |
| } |
| |
| /* |
| * If a file is moved, it will inherit the cow and compression flags of the new |
| * directory. |
| */ |
| static void fixup_inode_flags(struct inode *dir, struct inode *inode) |
| { |
| struct btrfs_inode *b_dir = BTRFS_I(dir); |
| struct btrfs_inode *b_inode = BTRFS_I(inode); |
| |
| if (b_dir->flags & BTRFS_INODE_NODATACOW) |
| b_inode->flags |= BTRFS_INODE_NODATACOW; |
| else |
| b_inode->flags &= ~BTRFS_INODE_NODATACOW; |
| |
| if (b_dir->flags & BTRFS_INODE_COMPRESS) |
| b_inode->flags |= BTRFS_INODE_COMPRESS; |
| else |
| b_inode->flags &= ~BTRFS_INODE_COMPRESS; |
| } |
| |
| static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry, |
| struct inode *new_dir, struct dentry *new_dentry) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(old_dir)->root; |
| struct btrfs_root *dest = BTRFS_I(new_dir)->root; |
| struct inode *new_inode = new_dentry->d_inode; |
| struct inode *old_inode = old_dentry->d_inode; |
| struct timespec ctime = CURRENT_TIME; |
| u64 index = 0; |
| u64 root_objectid; |
| int ret; |
| u64 old_ino = btrfs_ino(old_inode); |
| |
| if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) |
| return -EPERM; |
| |
| /* we only allow rename subvolume link between subvolumes */ |
| if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest) |
| return -EXDEV; |
| |
| if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID || |
| (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID)) |
| return -ENOTEMPTY; |
| |
| if (S_ISDIR(old_inode->i_mode) && new_inode && |
| new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) |
| return -ENOTEMPTY; |
| /* |
| * we're using rename to replace one file with another. |
| * and the replacement file is large. Start IO on it now so |
| * we don't add too much work to the end of the transaction |
| */ |
| if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size && |
| old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) |
| filemap_flush(old_inode->i_mapping); |
| |
| /* close the racy window with snapshot create/destroy ioctl */ |
| if (old_ino == BTRFS_FIRST_FREE_OBJECTID) |
| down_read(&root->fs_info->subvol_sem); |
| /* |
| * We want to reserve the absolute worst case amount of items. So if |
| * both inodes are subvols and we need to unlink them then that would |
| * require 4 item modifications, but if they are both normal inodes it |
| * would require 5 item modifications, so we'll assume their normal |
| * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items |
| * should cover the worst case number of items we'll modify. |
| */ |
| trans = btrfs_start_transaction(root, 20); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| goto out_notrans; |
| } |
| |
| if (dest != root) |
| btrfs_record_root_in_trans(trans, dest); |
| |
| ret = btrfs_set_inode_index(new_dir, &index); |
| if (ret) |
| goto out_fail; |
| |
| if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { |
| /* force full log commit if subvolume involved. */ |
| root->fs_info->last_trans_log_full_commit = trans->transid; |
| } else { |
| ret = btrfs_insert_inode_ref(trans, dest, |
| new_dentry->d_name.name, |
| new_dentry->d_name.len, |
| old_ino, |
| btrfs_ino(new_dir), index); |
| if (ret) |
| goto out_fail; |
| /* |
| * this is an ugly little race, but the rename is required |
| * to make sure that if we crash, the inode is either at the |
| * old name or the new one. pinning the log transaction lets |
| * us make sure we don't allow a log commit to come in after |
| * we unlink the name but before we add the new name back in. |
| */ |
| btrfs_pin_log_trans(root); |
| } |
| /* |
| * make sure the inode gets flushed if it is replacing |
| * something. |
| */ |
| if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode)) |
| btrfs_add_ordered_operation(trans, root, old_inode); |
| |
| old_dir->i_ctime = old_dir->i_mtime = ctime; |
| new_dir->i_ctime = new_dir->i_mtime = ctime; |
| old_inode->i_ctime = ctime; |
| |
| if (old_dentry->d_parent != new_dentry->d_parent) |
| btrfs_record_unlink_dir(trans, old_dir, old_inode, 1); |
| |
| if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) { |
| root_objectid = BTRFS_I(old_inode)->root->root_key.objectid; |
| ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid, |
| old_dentry->d_name.name, |
| old_dentry->d_name.len); |
| } else { |
| ret = __btrfs_unlink_inode(trans, root, old_dir, |
| old_dentry->d_inode, |
| old_dentry->d_name.name, |
| old_dentry->d_name.len); |
| if (!ret) |
| ret = btrfs_update_inode(trans, root, old_inode); |
| } |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_fail; |
| } |
| |
| if (new_inode) { |
| new_inode->i_ctime = CURRENT_TIME; |
| if (unlikely(btrfs_ino(new_inode) == |
| BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) { |
| root_objectid = BTRFS_I(new_inode)->location.objectid; |
| ret = btrfs_unlink_subvol(trans, dest, new_dir, |
| root_objectid, |
| new_dentry->d_name.name, |
| new_dentry->d_name.len); |
| BUG_ON(new_inode->i_nlink == 0); |
| } else { |
| ret = btrfs_unlink_inode(trans, dest, new_dir, |
| new_dentry->d_inode, |
| new_dentry->d_name.name, |
| new_dentry->d_name.len); |
| } |
| if (!ret && new_inode->i_nlink == 0) { |
| ret = btrfs_orphan_add(trans, new_dentry->d_inode); |
| BUG_ON(ret); |
| } |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_fail; |
| } |
| } |
| |
| fixup_inode_flags(new_dir, old_inode); |
| |
| ret = btrfs_add_link(trans, new_dir, old_inode, |
| new_dentry->d_name.name, |
| new_dentry->d_name.len, 0, index); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| goto out_fail; |
| } |
| |
| if (old_ino != BTRFS_FIRST_FREE_OBJECTID) { |
| struct dentry *parent = new_dentry->d_parent; |
| btrfs_log_new_name(trans, old_inode, old_dir, parent); |
| btrfs_end_log_trans(root); |
| } |
| out_fail: |
| btrfs_end_transaction(trans, root); |
| out_notrans: |
| if (old_ino == BTRFS_FIRST_FREE_OBJECTID) |
| up_read(&root->fs_info->subvol_sem); |
| |
| return ret; |
| } |
| |
| /* |
| * some fairly slow code that needs optimization. This walks the list |
| * of all the inodes with pending delalloc and forces them to disk. |
| */ |
| int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput) |
| { |
| struct list_head *head = &root->fs_info->delalloc_inodes; |
| struct btrfs_inode *binode; |
| struct inode *inode; |
| |
| if (root->fs_info->sb->s_flags & MS_RDONLY) |
| return -EROFS; |
| |
| spin_lock(&root->fs_info->delalloc_lock); |
| while (!list_empty(head)) { |
| binode = list_entry(head->next, struct btrfs_inode, |
| delalloc_inodes); |
| inode = igrab(&binode->vfs_inode); |
| if (!inode) |
| list_del_init(&binode->delalloc_inodes); |
| spin_unlock(&root->fs_info->delalloc_lock); |
| if (inode) { |
| filemap_flush(inode->i_mapping); |
| if (delay_iput) |
| btrfs_add_delayed_iput(inode); |
| else |
| iput(inode); |
| } |
| cond_resched(); |
| spin_lock(&root->fs_info->delalloc_lock); |
| } |
| spin_unlock(&root->fs_info->delalloc_lock); |
| |
| /* the filemap_flush will queue IO into the worker threads, but |
| * we have to make sure the IO is actually started and that |
| * ordered extents get created before we return |
| */ |
| atomic_inc(&root->fs_info->async_submit_draining); |
| while (atomic_read(&root->fs_info->nr_async_submits) || |
| atomic_read(&root->fs_info->async_delalloc_pages)) { |
| wait_event(root->fs_info->async_submit_wait, |
| (atomic_read(&root->fs_info->nr_async_submits) == 0 && |
| atomic_read(&root->fs_info->async_delalloc_pages) == 0)); |
| } |
| atomic_dec(&root->fs_info->async_submit_draining); |
| return 0; |
| } |
| |
| static int btrfs_symlink(struct inode *dir, struct dentry *dentry, |
| const char *symname) |
| { |
| struct btrfs_trans_handle *trans; |
| struct btrfs_root *root = BTRFS_I(dir)->root; |
| struct btrfs_path *path; |
| struct btrfs_key key; |
| struct inode *inode = NULL; |
| int err; |
| int drop_inode = 0; |
| u64 objectid; |
| u64 index = 0 ; |
| int name_len; |
| int datasize; |
| unsigned long ptr; |
| struct btrfs_file_extent_item *ei; |
| struct extent_buffer *leaf; |
| unsigned long nr = 0; |
| |
| name_len = strlen(symname) + 1; |
| if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root)) |
| return -ENAMETOOLONG; |
| |
| /* |
| * 2 items for inode item and ref |
| * 2 items for dir items |
| * 1 item for xattr if selinux is on |
| */ |
| trans = btrfs_start_transaction(root, 5); |
| if (IS_ERR(trans)) |
| return PTR_ERR(trans); |
| |
| err = btrfs_find_free_ino(root, &objectid); |
| if (err) |
| goto out_unlock; |
| |
| inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name, |
| dentry->d_name.len, btrfs_ino(dir), objectid, |
| S_IFLNK|S_IRWXUGO, &index); |
| if (IS_ERR(inode)) { |
| err = PTR_ERR(inode); |
| goto out_unlock; |
| } |
| |
| err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name); |
| if (err) { |
| drop_inode = 1; |
| goto out_unlock; |
| } |
| |
| /* |
| * If the active LSM wants to access the inode during |
| * d_instantiate it needs these. Smack checks to see |
| * if the filesystem supports xattrs by looking at the |
| * ops vector. |
| */ |
| inode->i_fop = &btrfs_file_operations; |
| inode->i_op = &btrfs_file_inode_operations; |
| |
| err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index); |
| if (err) |
| drop_inode = 1; |
| else { |
| inode->i_mapping->a_ops = &btrfs_aops; |
| inode->i_mapping->backing_dev_info = &root->fs_info->bdi; |
| BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops; |
| } |
| if (drop_inode) |
| goto out_unlock; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| err = -ENOMEM; |
| drop_inode = 1; |
| goto out_unlock; |
| } |
| key.objectid = btrfs_ino(inode); |
| key.offset = 0; |
| btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); |
| datasize = btrfs_file_extent_calc_inline_size(name_len); |
| err = btrfs_insert_empty_item(trans, root, path, &key, |
| datasize); |
| if (err) { |
| drop_inode = 1; |
| btrfs_free_path(path); |
| goto out_unlock; |
| } |
| leaf = path->nodes[0]; |
| ei = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| btrfs_set_file_extent_generation(leaf, ei, trans->transid); |
| btrfs_set_file_extent_type(leaf, ei, |
| BTRFS_FILE_EXTENT_INLINE); |
| btrfs_set_file_extent_encryption(leaf, ei, 0); |
| btrfs_set_file_extent_compression(leaf, ei, 0); |
| btrfs_set_file_extent_other_encoding(leaf, ei, 0); |
| btrfs_set_file_extent_ram_bytes(leaf, ei, name_len); |
| |
| ptr = btrfs_file_extent_inline_start(ei); |
| write_extent_buffer(leaf, symname, ptr, name_len); |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_free_path(path); |
| |
| inode->i_op = &btrfs_symlink_inode_operations; |
| inode->i_mapping->a_ops = &btrfs_symlink_aops; |
| inode->i_mapping->backing_dev_info = &root->fs_info->bdi; |
| inode_set_bytes(inode, name_len); |
| btrfs_i_size_write(inode, name_len - 1); |
| err = btrfs_update_inode(trans, root, inode); |
| if (err) |
| drop_inode = 1; |
| |
| out_unlock: |
| if (!err) |
| d_instantiate(dentry, inode); |
| nr = trans->blocks_used; |
| btrfs_end_transaction(trans, root); |
| if (drop_inode) { |
| inode_dec_link_count(inode); |
| iput(inode); |
| } |
| btrfs_btree_balance_dirty(root, nr); |
| return err; |
| } |
| |
| static int __btrfs_prealloc_file_range(struct inode *inode, int mode, |
| u64 start, u64 num_bytes, u64 min_size, |
| loff_t actual_len, u64 *alloc_hint, |
| struct btrfs_trans_handle *trans) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct btrfs_key ins; |
| u64 cur_offset = start; |
| u64 i_size; |
| int ret = 0; |
| bool own_trans = true; |
| |
| if (trans) |
| own_trans = false; |
| while (num_bytes > 0) { |
| if (own_trans) { |
| trans = btrfs_start_transaction(root, 3); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| break; |
| } |
| } |
| |
| ret = btrfs_reserve_extent(trans, root, num_bytes, min_size, |
| 0, *alloc_hint, &ins, 1); |
| if (ret) { |
| if (own_trans) |
| btrfs_end_transaction(trans, root); |
| break; |
| } |
| |
| ret = insert_reserved_file_extent(trans, inode, |
| cur_offset, ins.objectid, |
| ins.offset, ins.offset, |
| ins.offset, 0, 0, 0, |
| BTRFS_FILE_EXTENT_PREALLOC); |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| if (own_trans) |
| btrfs_end_transaction(trans, root); |
| break; |
| } |
| btrfs_drop_extent_cache(inode, cur_offset, |
| cur_offset + ins.offset -1, 0); |
| |
| num_bytes -= ins.offset; |
| cur_offset += ins.offset; |
| *alloc_hint = ins.objectid + ins.offset; |
| |
| inode->i_ctime = CURRENT_TIME; |
| BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC; |
| if (!(mode & FALLOC_FL_KEEP_SIZE) && |
| (actual_len > inode->i_size) && |
| (cur_offset > inode->i_size)) { |
| if (cur_offset > actual_len) |
| i_size = actual_len; |
| else |
| i_size = cur_offset; |
| i_size_write(inode, i_size); |
| btrfs_ordered_update_i_size(inode, i_size, NULL); |
| } |
| |
| ret = btrfs_update_inode(trans, root, inode); |
| |
| if (ret) { |
| btrfs_abort_transaction(trans, root, ret); |
| if (own_trans) |
| btrfs_end_transaction(trans, root); |
| break; |
| } |
| |
| if (own_trans) |
| btrfs_end_transaction(trans, root); |
| } |
| return ret; |
| } |
| |
| int btrfs_prealloc_file_range(struct inode *inode, int mode, |
| u64 start, u64 num_bytes, u64 min_size, |
| loff_t actual_len, u64 *alloc_hint) |
| { |
| return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, |
| min_size, actual_len, alloc_hint, |
| NULL); |
| } |
| |
| int btrfs_prealloc_file_range_trans(struct inode *inode, |
| struct btrfs_trans_handle *trans, int mode, |
| u64 start, u64 num_bytes, u64 min_size, |
| loff_t actual_len, u64 *alloc_hint) |
| { |
| return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, |
| min_size, actual_len, alloc_hint, trans); |
| } |
| |
| static int btrfs_set_page_dirty(struct page *page) |
| { |
| return __set_page_dirty_nobuffers(page); |
| } |
| |
| static int btrfs_permission(struct inode *inode, int mask) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| umode_t mode = inode->i_mode; |
| |
| if (mask & MAY_WRITE && |
| (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) { |
| if (btrfs_root_readonly(root)) |
| return -EROFS; |
| if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) |
| return -EACCES; |
| } |
| return generic_permission(inode, mask); |
| } |
| |
| static const struct inode_operations btrfs_dir_inode_operations = { |
| .getattr = btrfs_getattr, |
| .lookup = btrfs_lookup, |
| .create = btrfs_create, |
| .unlink = btrfs_unlink, |
| .link = btrfs_link, |
| .mkdir = btrfs_mkdir, |
| .rmdir = btrfs_rmdir, |
| .rename = btrfs_rename, |
| .symlink = btrfs_symlink, |
| .setattr = btrfs_setattr, |
| .mknod = btrfs_mknod, |
| .setxattr = btrfs_setxattr, |
| .getxattr = btrfs_getxattr, |
| .listxattr = btrfs_listxattr, |
| .removexattr = btrfs_removexattr, |
| .permission = btrfs_permission, |
| .get_acl = btrfs_get_acl, |
| }; |
| static const struct inode_operations btrfs_dir_ro_inode_operations = { |
| .lookup = btrfs_lookup, |
| .permission = btrfs_permission, |
| .get_acl = btrfs_get_acl, |
| }; |
| |
| static const struct file_operations btrfs_dir_file_operations = { |
| .llseek = generic_file_llseek, |
| .read = generic_read_dir, |
| .readdir = btrfs_real_readdir, |
| .unlocked_ioctl = btrfs_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = btrfs_ioctl, |
| #endif |
| .release = btrfs_release_file, |
| .fsync = btrfs_sync_file, |
| }; |
| |
| static struct extent_io_ops btrfs_extent_io_ops = { |
| .fill_delalloc = run_delalloc_range, |
| .submit_bio_hook = btrfs_submit_bio_hook, |
| .merge_bio_hook = btrfs_merge_bio_hook, |
| .readpage_end_io_hook = btrfs_readpage_end_io_hook, |
| .writepage_end_io_hook = btrfs_writepage_end_io_hook, |
| .writepage_start_hook = btrfs_writepage_start_hook, |
| .set_bit_hook = btrfs_set_bit_hook, |
| .clear_bit_hook = btrfs_clear_bit_hook, |
| .merge_extent_hook = btrfs_merge_extent_hook, |
| .split_extent_hook = btrfs_split_extent_hook, |
| }; |
| |
| /* |
| * btrfs doesn't support the bmap operation because swapfiles |
| * use bmap to make a mapping of extents in the file. They assume |
| * these extents won't change over the life of the file and they |
| * use the bmap result to do IO directly to the drive. |
| * |
| * the btrfs bmap call would return logical addresses that aren't |
| * suitable for IO and they also will change frequently as COW |
| * operations happen. So, swapfile + btrfs == corruption. |
| * |
| * For now we're avoiding this by dropping bmap. |
| */ |
| static const struct address_space_operations btrfs_aops = { |
| .readpage = btrfs_readpage, |
| .writepage = btrfs_writepage, |
| .writepages = btrfs_writepages, |
| .readpages = btrfs_readpages, |
| .direct_IO = btrfs_direct_IO, |
| .invalidatepage = btrfs_invalidatepage, |
| .releasepage = btrfs_releasepage, |
| .set_page_dirty = btrfs_set_page_dirty, |
| .error_remove_page = generic_error_remove_page, |
| }; |
| |
| static const struct address_space_operations btrfs_symlink_aops = { |
| .readpage = btrfs_readpage, |
| .writepage = btrfs_writepage, |
| .invalidatepage = btrfs_invalidatepage, |
| .releasepage = btrfs_releasepage, |
| }; |
| |
| static const struct inode_operations btrfs_file_inode_operations = { |
| .getattr = btrfs_getattr, |
| .setattr = btrfs_setattr, |
| .setxattr = btrfs_setxattr, |
| .getxattr = btrfs_getxattr, |
| .listxattr = btrfs_listxattr, |
| .removexattr = btrfs_removexattr, |
| .permission = btrfs_permission, |
| .fiemap = btrfs_fiemap, |
| .get_acl = btrfs_get_acl, |
| }; |
| static const struct inode_operations btrfs_special_inode_operations = { |
| .getattr = btrfs_getattr, |
| .setattr = btrfs_setattr, |
| .permission = btrfs_permission, |
| .setxattr = btrfs_setxattr, |
| .getxattr = btrfs_getxattr, |
| .listxattr = btrfs_listxattr, |
| .removexattr = btrfs_removexattr, |
| .get_acl = btrfs_get_acl, |
| }; |
| static const struct inode_operations btrfs_symlink_inode_operations = { |
| .readlink = generic_readlink, |
| .follow_link = page_follow_link_light, |
| .put_link = page_put_link, |
| .getattr = btrfs_getattr, |
| .setattr = btrfs_setattr, |
| .permission = btrfs_permission, |
| .setxattr = btrfs_setxattr, |
| .getxattr = btrfs_getxattr, |
| .listxattr = btrfs_listxattr, |
| .removexattr = btrfs_removexattr, |
| .get_acl = btrfs_get_acl, |
| }; |
| |
| const struct dentry_operations btrfs_dentry_operations = { |
| .d_delete = btrfs_dentry_delete, |
| .d_release = btrfs_dentry_release, |
| }; |