| /* |
| * 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/version.h> |
| #include <linux/fs.h> |
| #include <linux/blkdev.h> |
| #include <linux/scatterlist.h> |
| #include <linux/swap.h> |
| #include <linux/radix-tree.h> |
| #include <linux/writeback.h> |
| #include <linux/buffer_head.h> // for block_sync_page |
| #include <linux/workqueue.h> |
| #include <linux/kthread.h> |
| #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20) |
| # include <linux/freezer.h> |
| #else |
| # include <linux/sched.h> |
| #endif |
| #include "crc32c.h" |
| #include "ctree.h" |
| #include "disk-io.h" |
| #include "transaction.h" |
| #include "btrfs_inode.h" |
| #include "volumes.h" |
| #include "print-tree.h" |
| #include "async-thread.h" |
| #include "locking.h" |
| #include "ref-cache.h" |
| #include "tree-log.h" |
| |
| #if 0 |
| static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf) |
| { |
| if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) { |
| printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n", |
| (unsigned long long)extent_buffer_blocknr(buf), |
| (unsigned long long)btrfs_header_blocknr(buf)); |
| return 1; |
| } |
| return 0; |
| } |
| #endif |
| |
| static struct extent_io_ops btree_extent_io_ops; |
| static void end_workqueue_fn(struct btrfs_work *work); |
| |
| struct end_io_wq { |
| struct bio *bio; |
| bio_end_io_t *end_io; |
| void *private; |
| struct btrfs_fs_info *info; |
| int error; |
| int metadata; |
| struct list_head list; |
| struct btrfs_work work; |
| }; |
| |
| struct async_submit_bio { |
| struct inode *inode; |
| struct bio *bio; |
| struct list_head list; |
| extent_submit_bio_hook_t *submit_bio_hook; |
| int rw; |
| int mirror_num; |
| struct btrfs_work work; |
| }; |
| |
| struct extent_map *btree_get_extent(struct inode *inode, struct page *page, |
| size_t page_offset, u64 start, u64 len, |
| int create) |
| { |
| struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; |
| struct extent_map *em; |
| int ret; |
| |
| spin_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, start, len); |
| if (em) { |
| em->bdev = |
| BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; |
| spin_unlock(&em_tree->lock); |
| goto out; |
| } |
| spin_unlock(&em_tree->lock); |
| |
| em = alloc_extent_map(GFP_NOFS); |
| if (!em) { |
| em = ERR_PTR(-ENOMEM); |
| goto out; |
| } |
| em->start = 0; |
| em->len = (u64)-1; |
| em->block_start = 0; |
| em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; |
| |
| spin_lock(&em_tree->lock); |
| ret = add_extent_mapping(em_tree, em); |
| if (ret == -EEXIST) { |
| u64 failed_start = em->start; |
| u64 failed_len = em->len; |
| |
| printk("failed to insert %Lu %Lu -> %Lu into tree\n", |
| em->start, em->len, em->block_start); |
| free_extent_map(em); |
| em = lookup_extent_mapping(em_tree, start, len); |
| if (em) { |
| printk("after failing, found %Lu %Lu %Lu\n", |
| em->start, em->len, em->block_start); |
| ret = 0; |
| } else { |
| em = lookup_extent_mapping(em_tree, failed_start, |
| failed_len); |
| if (em) { |
| printk("double failure lookup gives us " |
| "%Lu %Lu -> %Lu\n", em->start, |
| em->len, em->block_start); |
| free_extent_map(em); |
| } |
| ret = -EIO; |
| } |
| } else if (ret) { |
| free_extent_map(em); |
| em = NULL; |
| } |
| spin_unlock(&em_tree->lock); |
| |
| if (ret) |
| em = ERR_PTR(ret); |
| out: |
| return em; |
| } |
| |
| u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len) |
| { |
| return btrfs_crc32c(seed, data, len); |
| } |
| |
| void btrfs_csum_final(u32 crc, char *result) |
| { |
| *(__le32 *)result = ~cpu_to_le32(crc); |
| } |
| |
| static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, |
| int verify) |
| { |
| char result[BTRFS_CRC32_SIZE]; |
| unsigned long len; |
| unsigned long cur_len; |
| unsigned long offset = BTRFS_CSUM_SIZE; |
| char *map_token = NULL; |
| char *kaddr; |
| unsigned long map_start; |
| unsigned long map_len; |
| int err; |
| u32 crc = ~(u32)0; |
| |
| len = buf->len - offset; |
| while(len > 0) { |
| err = map_private_extent_buffer(buf, offset, 32, |
| &map_token, &kaddr, |
| &map_start, &map_len, KM_USER0); |
| if (err) { |
| printk("failed to map extent buffer! %lu\n", |
| offset); |
| return 1; |
| } |
| cur_len = min(len, map_len - (offset - map_start)); |
| crc = btrfs_csum_data(root, kaddr + offset - map_start, |
| crc, cur_len); |
| len -= cur_len; |
| offset += cur_len; |
| unmap_extent_buffer(buf, map_token, KM_USER0); |
| } |
| btrfs_csum_final(crc, result); |
| |
| if (verify) { |
| /* FIXME, this is not good */ |
| if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) { |
| u32 val; |
| u32 found = 0; |
| memcpy(&found, result, BTRFS_CRC32_SIZE); |
| |
| read_extent_buffer(buf, &val, 0, BTRFS_CRC32_SIZE); |
| printk("btrfs: %s checksum verify failed on %llu " |
| "wanted %X found %X level %d\n", |
| root->fs_info->sb->s_id, |
| buf->start, val, found, btrfs_header_level(buf)); |
| return 1; |
| } |
| } else { |
| write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE); |
| } |
| return 0; |
| } |
| |
| static int verify_parent_transid(struct extent_io_tree *io_tree, |
| struct extent_buffer *eb, u64 parent_transid) |
| { |
| int ret; |
| |
| if (!parent_transid || btrfs_header_generation(eb) == parent_transid) |
| return 0; |
| |
| lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS); |
| if (extent_buffer_uptodate(io_tree, eb) && |
| btrfs_header_generation(eb) == parent_transid) { |
| ret = 0; |
| goto out; |
| } |
| printk("parent transid verify failed on %llu wanted %llu found %llu\n", |
| (unsigned long long)eb->start, |
| (unsigned long long)parent_transid, |
| (unsigned long long)btrfs_header_generation(eb)); |
| ret = 1; |
| clear_extent_buffer_uptodate(io_tree, eb); |
| out: |
| unlock_extent(io_tree, eb->start, eb->start + eb->len - 1, |
| GFP_NOFS); |
| return ret; |
| |
| } |
| |
| static int btree_read_extent_buffer_pages(struct btrfs_root *root, |
| struct extent_buffer *eb, |
| u64 start, u64 parent_transid) |
| { |
| struct extent_io_tree *io_tree; |
| int ret; |
| int num_copies = 0; |
| int mirror_num = 0; |
| |
| io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree; |
| while (1) { |
| ret = read_extent_buffer_pages(io_tree, eb, start, 1, |
| btree_get_extent, mirror_num); |
| if (!ret && |
| !verify_parent_transid(io_tree, eb, parent_transid)) |
| return ret; |
| printk("read extent buffer pages failed with ret %d mirror no %d\n", ret, mirror_num); |
| num_copies = btrfs_num_copies(&root->fs_info->mapping_tree, |
| eb->start, eb->len); |
| if (num_copies == 1) |
| return ret; |
| |
| mirror_num++; |
| if (mirror_num > num_copies) |
| return ret; |
| } |
| return -EIO; |
| } |
| |
| int csum_dirty_buffer(struct btrfs_root *root, struct page *page) |
| { |
| struct extent_io_tree *tree; |
| u64 start = (u64)page->index << PAGE_CACHE_SHIFT; |
| u64 found_start; |
| int found_level; |
| unsigned long len; |
| struct extent_buffer *eb; |
| int ret; |
| |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| |
| if (page->private == EXTENT_PAGE_PRIVATE) |
| goto out; |
| if (!page->private) |
| goto out; |
| len = page->private >> 2; |
| if (len == 0) { |
| WARN_ON(1); |
| } |
| eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS); |
| ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE, |
| btrfs_header_generation(eb)); |
| BUG_ON(ret); |
| found_start = btrfs_header_bytenr(eb); |
| if (found_start != start) { |
| printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n", |
| start, found_start, len); |
| WARN_ON(1); |
| goto err; |
| } |
| if (eb->first_page != page) { |
| printk("bad first page %lu %lu\n", eb->first_page->index, |
| page->index); |
| WARN_ON(1); |
| goto err; |
| } |
| if (!PageUptodate(page)) { |
| printk("csum not up to date page %lu\n", page->index); |
| WARN_ON(1); |
| goto err; |
| } |
| found_level = btrfs_header_level(eb); |
| |
| csum_tree_block(root, eb, 0); |
| err: |
| free_extent_buffer(eb); |
| out: |
| return 0; |
| } |
| |
| int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end, |
| struct extent_state *state) |
| { |
| struct extent_io_tree *tree; |
| u64 found_start; |
| int found_level; |
| unsigned long len; |
| struct extent_buffer *eb; |
| struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; |
| int ret = 0; |
| |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| if (page->private == EXTENT_PAGE_PRIVATE) |
| goto out; |
| if (!page->private) |
| goto out; |
| len = page->private >> 2; |
| if (len == 0) { |
| WARN_ON(1); |
| } |
| eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS); |
| |
| found_start = btrfs_header_bytenr(eb); |
| if (found_start != start) { |
| printk("bad tree block start %llu %llu\n", |
| (unsigned long long)found_start, |
| (unsigned long long)eb->start); |
| ret = -EIO; |
| goto err; |
| } |
| if (eb->first_page != page) { |
| printk("bad first page %lu %lu\n", eb->first_page->index, |
| page->index); |
| WARN_ON(1); |
| ret = -EIO; |
| goto err; |
| } |
| if (memcmp_extent_buffer(eb, root->fs_info->fsid, |
| (unsigned long)btrfs_header_fsid(eb), |
| BTRFS_FSID_SIZE)) { |
| printk("bad fsid on block %Lu\n", eb->start); |
| ret = -EIO; |
| goto err; |
| } |
| found_level = btrfs_header_level(eb); |
| |
| ret = csum_tree_block(root, eb, 1); |
| if (ret) |
| ret = -EIO; |
| |
| end = min_t(u64, eb->len, PAGE_CACHE_SIZE); |
| end = eb->start + end - 1; |
| err: |
| free_extent_buffer(eb); |
| out: |
| return ret; |
| } |
| |
| #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| static void end_workqueue_bio(struct bio *bio, int err) |
| #else |
| static int end_workqueue_bio(struct bio *bio, |
| unsigned int bytes_done, int err) |
| #endif |
| { |
| struct end_io_wq *end_io_wq = bio->bi_private; |
| struct btrfs_fs_info *fs_info; |
| |
| #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
| if (bio->bi_size) |
| return 1; |
| #endif |
| |
| fs_info = end_io_wq->info; |
| end_io_wq->error = err; |
| end_io_wq->work.func = end_workqueue_fn; |
| end_io_wq->work.flags = 0; |
| if (bio->bi_rw & (1 << BIO_RW)) |
| btrfs_queue_worker(&fs_info->endio_write_workers, |
| &end_io_wq->work); |
| else |
| btrfs_queue_worker(&fs_info->endio_workers, &end_io_wq->work); |
| |
| #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
| return 0; |
| #endif |
| } |
| |
| int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, |
| int metadata) |
| { |
| struct end_io_wq *end_io_wq; |
| end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS); |
| if (!end_io_wq) |
| return -ENOMEM; |
| |
| end_io_wq->private = bio->bi_private; |
| end_io_wq->end_io = bio->bi_end_io; |
| end_io_wq->info = info; |
| end_io_wq->error = 0; |
| end_io_wq->bio = bio; |
| end_io_wq->metadata = metadata; |
| |
| bio->bi_private = end_io_wq; |
| bio->bi_end_io = end_workqueue_bio; |
| return 0; |
| } |
| |
| unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info) |
| { |
| unsigned long limit = min_t(unsigned long, |
| info->workers.max_workers, |
| info->fs_devices->open_devices); |
| return 256 * limit; |
| } |
| |
| int btrfs_congested_async(struct btrfs_fs_info *info, int iodone) |
| { |
| return atomic_read(&info->nr_async_bios) > |
| btrfs_async_submit_limit(info); |
| } |
| |
| static void run_one_async_submit(struct btrfs_work *work) |
| { |
| struct btrfs_fs_info *fs_info; |
| struct async_submit_bio *async; |
| int limit; |
| |
| async = container_of(work, struct async_submit_bio, work); |
| fs_info = BTRFS_I(async->inode)->root->fs_info; |
| |
| limit = btrfs_async_submit_limit(fs_info); |
| limit = limit * 2 / 3; |
| |
| atomic_dec(&fs_info->nr_async_submits); |
| |
| if (atomic_read(&fs_info->nr_async_submits) < limit && |
| waitqueue_active(&fs_info->async_submit_wait)) |
| wake_up(&fs_info->async_submit_wait); |
| |
| async->submit_bio_hook(async->inode, async->rw, async->bio, |
| async->mirror_num); |
| kfree(async); |
| } |
| |
| int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode, |
| int rw, struct bio *bio, int mirror_num, |
| extent_submit_bio_hook_t *submit_bio_hook) |
| { |
| struct async_submit_bio *async; |
| int limit = btrfs_async_submit_limit(fs_info); |
| |
| async = kmalloc(sizeof(*async), GFP_NOFS); |
| if (!async) |
| return -ENOMEM; |
| |
| async->inode = inode; |
| async->rw = rw; |
| async->bio = bio; |
| async->mirror_num = mirror_num; |
| async->submit_bio_hook = submit_bio_hook; |
| async->work.func = run_one_async_submit; |
| async->work.flags = 0; |
| atomic_inc(&fs_info->nr_async_submits); |
| btrfs_queue_worker(&fs_info->workers, &async->work); |
| |
| if (atomic_read(&fs_info->nr_async_submits) > limit) { |
| wait_event_timeout(fs_info->async_submit_wait, |
| (atomic_read(&fs_info->nr_async_submits) < limit), |
| HZ/10); |
| |
| wait_event_timeout(fs_info->async_submit_wait, |
| (atomic_read(&fs_info->nr_async_bios) < limit), |
| HZ/10); |
| } |
| return 0; |
| } |
| |
| static int btree_csum_one_bio(struct bio *bio) |
| { |
| struct bio_vec *bvec = bio->bi_io_vec; |
| int bio_index = 0; |
| struct btrfs_root *root; |
| |
| WARN_ON(bio->bi_vcnt <= 0); |
| while(bio_index < bio->bi_vcnt) { |
| root = BTRFS_I(bvec->bv_page->mapping->host)->root; |
| csum_dirty_buffer(root, bvec->bv_page); |
| bio_index++; |
| bvec++; |
| } |
| return 0; |
| } |
| |
| static int __btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, |
| int mirror_num) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 offset; |
| int ret; |
| |
| offset = bio->bi_sector << 9; |
| |
| /* |
| * when we're called for a write, we're already in the async |
| * submission context. Just jump into btrfs_map_bio |
| */ |
| if (rw & (1 << BIO_RW)) { |
| btree_csum_one_bio(bio); |
| return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, |
| mirror_num, 1); |
| } |
| |
| /* |
| * called for a read, do the setup so that checksum validation |
| * can happen in the async kernel threads |
| */ |
| ret = btrfs_bio_wq_end_io(root->fs_info, bio, 1); |
| BUG_ON(ret); |
| |
| return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1); |
| } |
| |
| static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, |
| int mirror_num) |
| { |
| /* |
| * kthread helpers are used to submit writes so that checksumming |
| * can happen in parallel across all CPUs |
| */ |
| if (!(rw & (1 << BIO_RW))) { |
| return __btree_submit_bio_hook(inode, rw, bio, mirror_num); |
| } |
| return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, |
| inode, rw, bio, mirror_num, |
| __btree_submit_bio_hook); |
| } |
| |
| static int btree_writepage(struct page *page, struct writeback_control *wbc) |
| { |
| struct extent_io_tree *tree; |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| |
| if (current->flags & PF_MEMALLOC) { |
| redirty_page_for_writepage(wbc, page); |
| unlock_page(page); |
| return 0; |
| } |
| return extent_write_full_page(tree, page, btree_get_extent, wbc); |
| } |
| |
| static int btree_writepages(struct address_space *mapping, |
| struct writeback_control *wbc) |
| { |
| struct extent_io_tree *tree; |
| tree = &BTRFS_I(mapping->host)->io_tree; |
| if (wbc->sync_mode == WB_SYNC_NONE) { |
| u64 num_dirty; |
| u64 start = 0; |
| unsigned long thresh = 8 * 1024 * 1024; |
| |
| if (wbc->for_kupdate) |
| return 0; |
| |
| num_dirty = count_range_bits(tree, &start, (u64)-1, |
| thresh, EXTENT_DIRTY); |
| if (num_dirty < thresh) { |
| return 0; |
| } |
| } |
| return extent_writepages(tree, mapping, btree_get_extent, wbc); |
| } |
| |
| int btree_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, btree_get_extent); |
| } |
| |
| static int btree_releasepage(struct page *page, gfp_t gfp_flags) |
| { |
| struct extent_io_tree *tree; |
| struct extent_map_tree *map; |
| int ret; |
| |
| if (PageWriteback(page) || PageDirty(page)) |
| return 0; |
| |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| map = &BTRFS_I(page->mapping->host)->extent_tree; |
| |
| ret = try_release_extent_state(map, tree, page, gfp_flags); |
| if (!ret) { |
| return 0; |
| } |
| |
| ret = try_release_extent_buffer(tree, page); |
| if (ret == 1) { |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| page_cache_release(page); |
| } |
| |
| return ret; |
| } |
| |
| static void btree_invalidatepage(struct page *page, unsigned long offset) |
| { |
| struct extent_io_tree *tree; |
| tree = &BTRFS_I(page->mapping->host)->io_tree; |
| extent_invalidatepage(tree, page, offset); |
| btree_releasepage(page, GFP_NOFS); |
| if (PagePrivate(page)) { |
| printk("warning page private not zero on page %Lu\n", |
| page_offset(page)); |
| ClearPagePrivate(page); |
| set_page_private(page, 0); |
| page_cache_release(page); |
| } |
| } |
| |
| #if 0 |
| static int btree_writepage(struct page *page, struct writeback_control *wbc) |
| { |
| struct buffer_head *bh; |
| struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; |
| struct buffer_head *head; |
| if (!page_has_buffers(page)) { |
| create_empty_buffers(page, root->fs_info->sb->s_blocksize, |
| (1 << BH_Dirty)|(1 << BH_Uptodate)); |
| } |
| head = page_buffers(page); |
| bh = head; |
| do { |
| if (buffer_dirty(bh)) |
| csum_tree_block(root, bh, 0); |
| bh = bh->b_this_page; |
| } while (bh != head); |
| return block_write_full_page(page, btree_get_block, wbc); |
| } |
| #endif |
| |
| static struct address_space_operations btree_aops = { |
| .readpage = btree_readpage, |
| .writepage = btree_writepage, |
| .writepages = btree_writepages, |
| .releasepage = btree_releasepage, |
| .invalidatepage = btree_invalidatepage, |
| .sync_page = block_sync_page, |
| }; |
| |
| int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize, |
| u64 parent_transid) |
| { |
| struct extent_buffer *buf = NULL; |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| int ret = 0; |
| |
| buf = btrfs_find_create_tree_block(root, bytenr, blocksize); |
| if (!buf) |
| return 0; |
| read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree, |
| buf, 0, 0, btree_get_extent, 0); |
| free_extent_buffer(buf); |
| return ret; |
| } |
| |
| struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root, |
| u64 bytenr, u32 blocksize) |
| { |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| struct extent_buffer *eb; |
| eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree, |
| bytenr, blocksize, GFP_NOFS); |
| return eb; |
| } |
| |
| struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, |
| u64 bytenr, u32 blocksize) |
| { |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| struct extent_buffer *eb; |
| |
| eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree, |
| bytenr, blocksize, NULL, GFP_NOFS); |
| return eb; |
| } |
| |
| |
| int btrfs_write_tree_block(struct extent_buffer *buf) |
| { |
| return btrfs_fdatawrite_range(buf->first_page->mapping, buf->start, |
| buf->start + buf->len - 1, WB_SYNC_NONE); |
| } |
| |
| int btrfs_wait_tree_block_writeback(struct extent_buffer *buf) |
| { |
| return btrfs_wait_on_page_writeback_range(buf->first_page->mapping, |
| buf->start, buf->start + buf->len -1); |
| } |
| |
| struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, |
| u32 blocksize, u64 parent_transid) |
| { |
| struct extent_buffer *buf = NULL; |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| struct extent_io_tree *io_tree; |
| int ret; |
| |
| io_tree = &BTRFS_I(btree_inode)->io_tree; |
| |
| buf = btrfs_find_create_tree_block(root, bytenr, blocksize); |
| if (!buf) |
| return NULL; |
| |
| ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid); |
| |
| if (ret == 0) { |
| buf->flags |= EXTENT_UPTODATE; |
| } else { |
| WARN_ON(1); |
| } |
| return buf; |
| |
| } |
| |
| int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, |
| struct extent_buffer *buf) |
| { |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| if (btrfs_header_generation(buf) == |
| root->fs_info->running_transaction->transid) { |
| WARN_ON(!btrfs_tree_locked(buf)); |
| clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree, |
| buf); |
| } |
| return 0; |
| } |
| |
| static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize, |
| u32 stripesize, struct btrfs_root *root, |
| struct btrfs_fs_info *fs_info, |
| u64 objectid) |
| { |
| root->node = NULL; |
| root->inode = NULL; |
| root->commit_root = NULL; |
| root->ref_tree = NULL; |
| root->sectorsize = sectorsize; |
| root->nodesize = nodesize; |
| root->leafsize = leafsize; |
| root->stripesize = stripesize; |
| root->ref_cows = 0; |
| root->track_dirty = 0; |
| |
| root->fs_info = fs_info; |
| root->objectid = objectid; |
| root->last_trans = 0; |
| root->highest_inode = 0; |
| root->last_inode_alloc = 0; |
| root->name = NULL; |
| root->in_sysfs = 0; |
| |
| INIT_LIST_HEAD(&root->dirty_list); |
| INIT_LIST_HEAD(&root->orphan_list); |
| INIT_LIST_HEAD(&root->dead_list); |
| spin_lock_init(&root->node_lock); |
| spin_lock_init(&root->list_lock); |
| mutex_init(&root->objectid_mutex); |
| mutex_init(&root->log_mutex); |
| extent_io_tree_init(&root->dirty_log_pages, |
| fs_info->btree_inode->i_mapping, GFP_NOFS); |
| |
| btrfs_leaf_ref_tree_init(&root->ref_tree_struct); |
| root->ref_tree = &root->ref_tree_struct; |
| |
| memset(&root->root_key, 0, sizeof(root->root_key)); |
| memset(&root->root_item, 0, sizeof(root->root_item)); |
| memset(&root->defrag_progress, 0, sizeof(root->defrag_progress)); |
| memset(&root->root_kobj, 0, sizeof(root->root_kobj)); |
| root->defrag_trans_start = fs_info->generation; |
| init_completion(&root->kobj_unregister); |
| root->defrag_running = 0; |
| root->defrag_level = 0; |
| root->root_key.objectid = objectid; |
| return 0; |
| } |
| |
| static int find_and_setup_root(struct btrfs_root *tree_root, |
| struct btrfs_fs_info *fs_info, |
| u64 objectid, |
| struct btrfs_root *root) |
| { |
| int ret; |
| u32 blocksize; |
| |
| __setup_root(tree_root->nodesize, tree_root->leafsize, |
| tree_root->sectorsize, tree_root->stripesize, |
| root, fs_info, objectid); |
| ret = btrfs_find_last_root(tree_root, objectid, |
| &root->root_item, &root->root_key); |
| BUG_ON(ret); |
| |
| blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item)); |
| root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item), |
| blocksize, 0); |
| BUG_ON(!root->node); |
| return 0; |
| } |
| |
| int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_fs_info *fs_info) |
| { |
| struct extent_buffer *eb; |
| struct btrfs_root *log_root_tree = fs_info->log_root_tree; |
| u64 start = 0; |
| u64 end = 0; |
| int ret; |
| |
| if (!log_root_tree) |
| return 0; |
| |
| while(1) { |
| ret = find_first_extent_bit(&log_root_tree->dirty_log_pages, |
| 0, &start, &end, EXTENT_DIRTY); |
| if (ret) |
| break; |
| |
| clear_extent_dirty(&log_root_tree->dirty_log_pages, |
| start, end, GFP_NOFS); |
| } |
| eb = fs_info->log_root_tree->node; |
| |
| WARN_ON(btrfs_header_level(eb) != 0); |
| WARN_ON(btrfs_header_nritems(eb) != 0); |
| |
| ret = btrfs_free_reserved_extent(fs_info->tree_root, |
| eb->start, eb->len); |
| BUG_ON(ret); |
| |
| free_extent_buffer(eb); |
| kfree(fs_info->log_root_tree); |
| fs_info->log_root_tree = NULL; |
| return 0; |
| } |
| |
| int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_fs_info *fs_info) |
| { |
| struct btrfs_root *root; |
| struct btrfs_root *tree_root = fs_info->tree_root; |
| |
| root = kzalloc(sizeof(*root), GFP_NOFS); |
| if (!root) |
| return -ENOMEM; |
| |
| __setup_root(tree_root->nodesize, tree_root->leafsize, |
| tree_root->sectorsize, tree_root->stripesize, |
| root, fs_info, BTRFS_TREE_LOG_OBJECTID); |
| |
| root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID; |
| root->root_key.type = BTRFS_ROOT_ITEM_KEY; |
| root->root_key.offset = BTRFS_TREE_LOG_OBJECTID; |
| root->ref_cows = 0; |
| |
| root->node = btrfs_alloc_free_block(trans, root, root->leafsize, |
| 0, BTRFS_TREE_LOG_OBJECTID, |
| trans->transid, 0, 0, 0); |
| |
| btrfs_set_header_nritems(root->node, 0); |
| btrfs_set_header_level(root->node, 0); |
| btrfs_set_header_bytenr(root->node, root->node->start); |
| btrfs_set_header_generation(root->node, trans->transid); |
| btrfs_set_header_owner(root->node, BTRFS_TREE_LOG_OBJECTID); |
| |
| write_extent_buffer(root->node, root->fs_info->fsid, |
| (unsigned long)btrfs_header_fsid(root->node), |
| BTRFS_FSID_SIZE); |
| btrfs_mark_buffer_dirty(root->node); |
| btrfs_tree_unlock(root->node); |
| fs_info->log_root_tree = root; |
| return 0; |
| } |
| |
| struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root, |
| struct btrfs_key *location) |
| { |
| struct btrfs_root *root; |
| struct btrfs_fs_info *fs_info = tree_root->fs_info; |
| struct btrfs_path *path; |
| struct extent_buffer *l; |
| u64 highest_inode; |
| u32 blocksize; |
| int ret = 0; |
| |
| root = kzalloc(sizeof(*root), GFP_NOFS); |
| if (!root) |
| return ERR_PTR(-ENOMEM); |
| if (location->offset == (u64)-1) { |
| ret = find_and_setup_root(tree_root, fs_info, |
| location->objectid, root); |
| if (ret) { |
| kfree(root); |
| return ERR_PTR(ret); |
| } |
| goto insert; |
| } |
| |
| __setup_root(tree_root->nodesize, tree_root->leafsize, |
| tree_root->sectorsize, tree_root->stripesize, |
| root, fs_info, location->objectid); |
| |
| path = btrfs_alloc_path(); |
| BUG_ON(!path); |
| ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0); |
| if (ret != 0) { |
| if (ret > 0) |
| ret = -ENOENT; |
| goto out; |
| } |
| l = path->nodes[0]; |
| read_extent_buffer(l, &root->root_item, |
| btrfs_item_ptr_offset(l, path->slots[0]), |
| sizeof(root->root_item)); |
| memcpy(&root->root_key, location, sizeof(*location)); |
| ret = 0; |
| out: |
| btrfs_release_path(root, path); |
| btrfs_free_path(path); |
| if (ret) { |
| kfree(root); |
| return ERR_PTR(ret); |
| } |
| blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item)); |
| root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item), |
| blocksize, 0); |
| BUG_ON(!root->node); |
| insert: |
| if (location->objectid != BTRFS_TREE_LOG_OBJECTID) { |
| root->ref_cows = 1; |
| ret = btrfs_find_highest_inode(root, &highest_inode); |
| if (ret == 0) { |
| root->highest_inode = highest_inode; |
| root->last_inode_alloc = highest_inode; |
| } |
| } |
| return root; |
| } |
| |
| struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, |
| u64 root_objectid) |
| { |
| struct btrfs_root *root; |
| |
| if (root_objectid == BTRFS_ROOT_TREE_OBJECTID) |
| return fs_info->tree_root; |
| if (root_objectid == BTRFS_EXTENT_TREE_OBJECTID) |
| return fs_info->extent_root; |
| |
| root = radix_tree_lookup(&fs_info->fs_roots_radix, |
| (unsigned long)root_objectid); |
| return root; |
| } |
| |
| struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, |
| struct btrfs_key *location) |
| { |
| struct btrfs_root *root; |
| int ret; |
| |
| if (location->objectid == BTRFS_ROOT_TREE_OBJECTID) |
| return fs_info->tree_root; |
| if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID) |
| return fs_info->extent_root; |
| if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID) |
| return fs_info->chunk_root; |
| if (location->objectid == BTRFS_DEV_TREE_OBJECTID) |
| return fs_info->dev_root; |
| |
| root = radix_tree_lookup(&fs_info->fs_roots_radix, |
| (unsigned long)location->objectid); |
| if (root) |
| return root; |
| |
| root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location); |
| if (IS_ERR(root)) |
| return root; |
| ret = radix_tree_insert(&fs_info->fs_roots_radix, |
| (unsigned long)root->root_key.objectid, |
| root); |
| if (ret) { |
| free_extent_buffer(root->node); |
| kfree(root); |
| return ERR_PTR(ret); |
| } |
| ret = btrfs_find_dead_roots(fs_info->tree_root, |
| root->root_key.objectid, root); |
| BUG_ON(ret); |
| |
| return root; |
| } |
| |
| struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info, |
| struct btrfs_key *location, |
| const char *name, int namelen) |
| { |
| struct btrfs_root *root; |
| int ret; |
| |
| root = btrfs_read_fs_root_no_name(fs_info, location); |
| if (!root) |
| return NULL; |
| |
| if (root->in_sysfs) |
| return root; |
| |
| ret = btrfs_set_root_name(root, name, namelen); |
| if (ret) { |
| free_extent_buffer(root->node); |
| kfree(root); |
| return ERR_PTR(ret); |
| } |
| |
| ret = btrfs_sysfs_add_root(root); |
| if (ret) { |
| free_extent_buffer(root->node); |
| kfree(root->name); |
| kfree(root); |
| return ERR_PTR(ret); |
| } |
| root->in_sysfs = 1; |
| return root; |
| } |
| #if 0 |
| static int add_hasher(struct btrfs_fs_info *info, char *type) { |
| struct btrfs_hasher *hasher; |
| |
| hasher = kmalloc(sizeof(*hasher), GFP_NOFS); |
| if (!hasher) |
| return -ENOMEM; |
| hasher->hash_tfm = crypto_alloc_hash(type, 0, CRYPTO_ALG_ASYNC); |
| if (!hasher->hash_tfm) { |
| kfree(hasher); |
| return -EINVAL; |
| } |
| spin_lock(&info->hash_lock); |
| list_add(&hasher->list, &info->hashers); |
| spin_unlock(&info->hash_lock); |
| return 0; |
| } |
| #endif |
| |
| static int btrfs_congested_fn(void *congested_data, int bdi_bits) |
| { |
| struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data; |
| int ret = 0; |
| struct list_head *cur; |
| struct btrfs_device *device; |
| struct backing_dev_info *bdi; |
| |
| if ((bdi_bits & (1 << BDI_write_congested)) && |
| btrfs_congested_async(info, 0)) |
| return 1; |
| |
| list_for_each(cur, &info->fs_devices->devices) { |
| device = list_entry(cur, struct btrfs_device, dev_list); |
| if (!device->bdev) |
| continue; |
| bdi = blk_get_backing_dev_info(device->bdev); |
| if (bdi && bdi_congested(bdi, bdi_bits)) { |
| ret = 1; |
| break; |
| } |
| } |
| return ret; |
| } |
| |
| /* |
| * this unplugs every device on the box, and it is only used when page |
| * is null |
| */ |
| static void __unplug_io_fn(struct backing_dev_info *bdi, struct page *page) |
| { |
| struct list_head *cur; |
| struct btrfs_device *device; |
| struct btrfs_fs_info *info; |
| |
| info = (struct btrfs_fs_info *)bdi->unplug_io_data; |
| list_for_each(cur, &info->fs_devices->devices) { |
| device = list_entry(cur, struct btrfs_device, dev_list); |
| bdi = blk_get_backing_dev_info(device->bdev); |
| if (bdi->unplug_io_fn) { |
| bdi->unplug_io_fn(bdi, page); |
| } |
| } |
| } |
| |
| void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page) |
| { |
| struct inode *inode; |
| struct extent_map_tree *em_tree; |
| struct extent_map *em; |
| struct address_space *mapping; |
| u64 offset; |
| |
| /* the generic O_DIRECT read code does this */ |
| if (!page) { |
| __unplug_io_fn(bdi, page); |
| return; |
| } |
| |
| /* |
| * page->mapping may change at any time. Get a consistent copy |
| * and use that for everything below |
| */ |
| smp_mb(); |
| mapping = page->mapping; |
| if (!mapping) |
| return; |
| |
| inode = mapping->host; |
| offset = page_offset(page); |
| |
| em_tree = &BTRFS_I(inode)->extent_tree; |
| spin_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE); |
| spin_unlock(&em_tree->lock); |
| if (!em) { |
| __unplug_io_fn(bdi, page); |
| return; |
| } |
| |
| if (em->block_start >= EXTENT_MAP_LAST_BYTE) { |
| free_extent_map(em); |
| __unplug_io_fn(bdi, page); |
| return; |
| } |
| offset = offset - em->start; |
| btrfs_unplug_page(&BTRFS_I(inode)->root->fs_info->mapping_tree, |
| em->block_start + offset, page); |
| free_extent_map(em); |
| } |
| |
| static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi) |
| { |
| #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| bdi_init(bdi); |
| #endif |
| bdi->ra_pages = default_backing_dev_info.ra_pages; |
| bdi->state = 0; |
| bdi->capabilities = default_backing_dev_info.capabilities; |
| bdi->unplug_io_fn = btrfs_unplug_io_fn; |
| bdi->unplug_io_data = info; |
| bdi->congested_fn = btrfs_congested_fn; |
| bdi->congested_data = info; |
| return 0; |
| } |
| |
| static int bio_ready_for_csum(struct bio *bio) |
| { |
| u64 length = 0; |
| u64 buf_len = 0; |
| u64 start = 0; |
| struct page *page; |
| struct extent_io_tree *io_tree = NULL; |
| struct btrfs_fs_info *info = NULL; |
| struct bio_vec *bvec; |
| int i; |
| int ret; |
| |
| bio_for_each_segment(bvec, bio, i) { |
| page = bvec->bv_page; |
| if (page->private == EXTENT_PAGE_PRIVATE) { |
| length += bvec->bv_len; |
| continue; |
| } |
| if (!page->private) { |
| length += bvec->bv_len; |
| continue; |
| } |
| length = bvec->bv_len; |
| buf_len = page->private >> 2; |
| start = page_offset(page) + bvec->bv_offset; |
| io_tree = &BTRFS_I(page->mapping->host)->io_tree; |
| info = BTRFS_I(page->mapping->host)->root->fs_info; |
| } |
| /* are we fully contained in this bio? */ |
| if (buf_len <= length) |
| return 1; |
| |
| ret = extent_range_uptodate(io_tree, start + length, |
| start + buf_len - 1); |
| if (ret == 1) |
| return ret; |
| return ret; |
| } |
| |
| /* |
| * called by the kthread helper functions to finally call the bio end_io |
| * functions. This is where read checksum verification actually happens |
| */ |
| static void end_workqueue_fn(struct btrfs_work *work) |
| { |
| struct bio *bio; |
| struct end_io_wq *end_io_wq; |
| struct btrfs_fs_info *fs_info; |
| int error; |
| |
| end_io_wq = container_of(work, struct end_io_wq, work); |
| bio = end_io_wq->bio; |
| fs_info = end_io_wq->info; |
| |
| /* metadata bios are special because the whole tree block must |
| * be checksummed at once. This makes sure the entire block is in |
| * ram and up to date before trying to verify things. For |
| * blocksize <= pagesize, it is basically a noop |
| */ |
| if (end_io_wq->metadata && !bio_ready_for_csum(bio)) { |
| btrfs_queue_worker(&fs_info->endio_workers, |
| &end_io_wq->work); |
| return; |
| } |
| error = end_io_wq->error; |
| bio->bi_private = end_io_wq->private; |
| bio->bi_end_io = end_io_wq->end_io; |
| kfree(end_io_wq); |
| #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23) |
| bio_endio(bio, bio->bi_size, error); |
| #else |
| bio_endio(bio, error); |
| #endif |
| } |
| |
| static int cleaner_kthread(void *arg) |
| { |
| struct btrfs_root *root = arg; |
| |
| do { |
| smp_mb(); |
| if (root->fs_info->closing) |
| break; |
| |
| vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE); |
| mutex_lock(&root->fs_info->cleaner_mutex); |
| btrfs_clean_old_snapshots(root); |
| mutex_unlock(&root->fs_info->cleaner_mutex); |
| |
| if (freezing(current)) { |
| refrigerator(); |
| } else { |
| smp_mb(); |
| if (root->fs_info->closing) |
| break; |
| set_current_state(TASK_INTERRUPTIBLE); |
| schedule(); |
| __set_current_state(TASK_RUNNING); |
| } |
| } while (!kthread_should_stop()); |
| return 0; |
| } |
| |
| static int transaction_kthread(void *arg) |
| { |
| struct btrfs_root *root = arg; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_transaction *cur; |
| unsigned long now; |
| unsigned long delay; |
| int ret; |
| |
| do { |
| smp_mb(); |
| if (root->fs_info->closing) |
| break; |
| |
| delay = HZ * 30; |
| vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE); |
| mutex_lock(&root->fs_info->transaction_kthread_mutex); |
| |
| if (root->fs_info->total_ref_cache_size > 20 * 1024 * 1024) { |
| printk("btrfs: total reference cache size %Lu\n", |
| root->fs_info->total_ref_cache_size); |
| } |
| |
| mutex_lock(&root->fs_info->trans_mutex); |
| cur = root->fs_info->running_transaction; |
| if (!cur) { |
| mutex_unlock(&root->fs_info->trans_mutex); |
| goto sleep; |
| } |
| |
| now = get_seconds(); |
| if (now < cur->start_time || now - cur->start_time < 30) { |
| mutex_unlock(&root->fs_info->trans_mutex); |
| delay = HZ * 5; |
| goto sleep; |
| } |
| mutex_unlock(&root->fs_info->trans_mutex); |
| trans = btrfs_start_transaction(root, 1); |
| ret = btrfs_commit_transaction(trans, root); |
| sleep: |
| wake_up_process(root->fs_info->cleaner_kthread); |
| mutex_unlock(&root->fs_info->transaction_kthread_mutex); |
| |
| if (freezing(current)) { |
| refrigerator(); |
| } else { |
| if (root->fs_info->closing) |
| break; |
| set_current_state(TASK_INTERRUPTIBLE); |
| schedule_timeout(delay); |
| __set_current_state(TASK_RUNNING); |
| } |
| } while (!kthread_should_stop()); |
| return 0; |
| } |
| |
| struct btrfs_root *open_ctree(struct super_block *sb, |
| struct btrfs_fs_devices *fs_devices, |
| char *options) |
| { |
| u32 sectorsize; |
| u32 nodesize; |
| u32 leafsize; |
| u32 blocksize; |
| u32 stripesize; |
| struct buffer_head *bh; |
| struct btrfs_root *extent_root = kzalloc(sizeof(struct btrfs_root), |
| GFP_NOFS); |
| struct btrfs_root *tree_root = kzalloc(sizeof(struct btrfs_root), |
| GFP_NOFS); |
| struct btrfs_fs_info *fs_info = kzalloc(sizeof(*fs_info), |
| GFP_NOFS); |
| struct btrfs_root *chunk_root = kzalloc(sizeof(struct btrfs_root), |
| GFP_NOFS); |
| struct btrfs_root *dev_root = kzalloc(sizeof(struct btrfs_root), |
| GFP_NOFS); |
| struct btrfs_root *log_tree_root; |
| |
| int ret; |
| int err = -EINVAL; |
| |
| struct btrfs_super_block *disk_super; |
| |
| if (!extent_root || !tree_root || !fs_info) { |
| err = -ENOMEM; |
| goto fail; |
| } |
| INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS); |
| INIT_LIST_HEAD(&fs_info->trans_list); |
| INIT_LIST_HEAD(&fs_info->dead_roots); |
| INIT_LIST_HEAD(&fs_info->hashers); |
| INIT_LIST_HEAD(&fs_info->delalloc_inodes); |
| spin_lock_init(&fs_info->hash_lock); |
| spin_lock_init(&fs_info->delalloc_lock); |
| spin_lock_init(&fs_info->new_trans_lock); |
| spin_lock_init(&fs_info->ref_cache_lock); |
| |
| init_completion(&fs_info->kobj_unregister); |
| fs_info->tree_root = tree_root; |
| fs_info->extent_root = extent_root; |
| fs_info->chunk_root = chunk_root; |
| fs_info->dev_root = dev_root; |
| fs_info->fs_devices = fs_devices; |
| INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots); |
| INIT_LIST_HEAD(&fs_info->space_info); |
| btrfs_mapping_init(&fs_info->mapping_tree); |
| atomic_set(&fs_info->nr_async_submits, 0); |
| atomic_set(&fs_info->nr_async_bios, 0); |
| atomic_set(&fs_info->throttles, 0); |
| atomic_set(&fs_info->throttle_gen, 0); |
| fs_info->sb = sb; |
| fs_info->max_extent = (u64)-1; |
| fs_info->max_inline = 8192 * 1024; |
| setup_bdi(fs_info, &fs_info->bdi); |
| fs_info->btree_inode = new_inode(sb); |
| fs_info->btree_inode->i_ino = 1; |
| fs_info->btree_inode->i_nlink = 1; |
| fs_info->thread_pool_size = min(num_online_cpus() + 2, 8); |
| |
| INIT_LIST_HEAD(&fs_info->ordered_extents); |
| spin_lock_init(&fs_info->ordered_extent_lock); |
| |
| sb->s_blocksize = 4096; |
| sb->s_blocksize_bits = blksize_bits(4096); |
| |
| /* |
| * we set the i_size on the btree inode to the max possible int. |
| * the real end of the address space is determined by all of |
| * the devices in the system |
| */ |
| fs_info->btree_inode->i_size = OFFSET_MAX; |
| fs_info->btree_inode->i_mapping->a_ops = &btree_aops; |
| fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi; |
| |
| extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree, |
| fs_info->btree_inode->i_mapping, |
| GFP_NOFS); |
| extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree, |
| GFP_NOFS); |
| |
| BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops; |
| |
| spin_lock_init(&fs_info->block_group_cache_lock); |
| fs_info->block_group_cache_tree.rb_node = NULL; |
| |
| extent_io_tree_init(&fs_info->pinned_extents, |
| fs_info->btree_inode->i_mapping, GFP_NOFS); |
| extent_io_tree_init(&fs_info->pending_del, |
| fs_info->btree_inode->i_mapping, GFP_NOFS); |
| extent_io_tree_init(&fs_info->extent_ins, |
| fs_info->btree_inode->i_mapping, GFP_NOFS); |
| fs_info->do_barriers = 1; |
| |
| BTRFS_I(fs_info->btree_inode)->root = tree_root; |
| memset(&BTRFS_I(fs_info->btree_inode)->location, 0, |
| sizeof(struct btrfs_key)); |
| insert_inode_hash(fs_info->btree_inode); |
| |
| mutex_init(&fs_info->trans_mutex); |
| mutex_init(&fs_info->tree_log_mutex); |
| mutex_init(&fs_info->drop_mutex); |
| mutex_init(&fs_info->alloc_mutex); |
| mutex_init(&fs_info->chunk_mutex); |
| mutex_init(&fs_info->transaction_kthread_mutex); |
| mutex_init(&fs_info->cleaner_mutex); |
| mutex_init(&fs_info->volume_mutex); |
| init_waitqueue_head(&fs_info->transaction_throttle); |
| init_waitqueue_head(&fs_info->transaction_wait); |
| init_waitqueue_head(&fs_info->async_submit_wait); |
| init_waitqueue_head(&fs_info->tree_log_wait); |
| atomic_set(&fs_info->tree_log_commit, 0); |
| atomic_set(&fs_info->tree_log_writers, 0); |
| fs_info->tree_log_transid = 0; |
| |
| #if 0 |
| ret = add_hasher(fs_info, "crc32c"); |
| if (ret) { |
| printk("btrfs: failed hash setup, modprobe cryptomgr?\n"); |
| err = -ENOMEM; |
| goto fail_iput; |
| } |
| #endif |
| __setup_root(4096, 4096, 4096, 4096, tree_root, |
| fs_info, BTRFS_ROOT_TREE_OBJECTID); |
| |
| |
| bh = __bread(fs_devices->latest_bdev, |
| BTRFS_SUPER_INFO_OFFSET / 4096, 4096); |
| if (!bh) |
| goto fail_iput; |
| |
| memcpy(&fs_info->super_copy, bh->b_data, sizeof(fs_info->super_copy)); |
| brelse(bh); |
| |
| memcpy(fs_info->fsid, fs_info->super_copy.fsid, BTRFS_FSID_SIZE); |
| |
| disk_super = &fs_info->super_copy; |
| if (!btrfs_super_root(disk_super)) |
| goto fail_sb_buffer; |
| |
| err = btrfs_parse_options(tree_root, options); |
| if (err) |
| goto fail_sb_buffer; |
| |
| /* |
| * we need to start all the end_io workers up front because the |
| * queue work function gets called at interrupt time, and so it |
| * cannot dynamically grow. |
| */ |
| btrfs_init_workers(&fs_info->workers, "worker", |
| fs_info->thread_pool_size); |
| btrfs_init_workers(&fs_info->submit_workers, "submit", |
| min_t(u64, fs_devices->num_devices, |
| fs_info->thread_pool_size)); |
| |
| /* a higher idle thresh on the submit workers makes it much more |
| * likely that bios will be send down in a sane order to the |
| * devices |
| */ |
| fs_info->submit_workers.idle_thresh = 64; |
| |
| /* fs_info->workers is responsible for checksumming file data |
| * blocks and metadata. Using a larger idle thresh allows each |
| * worker thread to operate on things in roughly the order they |
| * were sent by the writeback daemons, improving overall locality |
| * of the IO going down the pipe. |
| */ |
| fs_info->workers.idle_thresh = 128; |
| |
| btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1); |
| btrfs_init_workers(&fs_info->endio_workers, "endio", |
| fs_info->thread_pool_size); |
| btrfs_init_workers(&fs_info->endio_write_workers, "endio-write", |
| fs_info->thread_pool_size); |
| |
| /* |
| * endios are largely parallel and should have a very |
| * low idle thresh |
| */ |
| fs_info->endio_workers.idle_thresh = 4; |
| fs_info->endio_write_workers.idle_thresh = 64; |
| |
| btrfs_start_workers(&fs_info->workers, 1); |
| btrfs_start_workers(&fs_info->submit_workers, 1); |
| btrfs_start_workers(&fs_info->fixup_workers, 1); |
| btrfs_start_workers(&fs_info->endio_workers, fs_info->thread_pool_size); |
| btrfs_start_workers(&fs_info->endio_write_workers, |
| fs_info->thread_pool_size); |
| |
| err = -EINVAL; |
| if (btrfs_super_num_devices(disk_super) > fs_devices->open_devices) { |
| printk("Btrfs: wanted %llu devices, but found %llu\n", |
| (unsigned long long)btrfs_super_num_devices(disk_super), |
| (unsigned long long)fs_devices->open_devices); |
| if (btrfs_test_opt(tree_root, DEGRADED)) |
| printk("continuing in degraded mode\n"); |
| else { |
| goto fail_sb_buffer; |
| } |
| } |
| |
| fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super); |
| |
| nodesize = btrfs_super_nodesize(disk_super); |
| leafsize = btrfs_super_leafsize(disk_super); |
| sectorsize = btrfs_super_sectorsize(disk_super); |
| stripesize = btrfs_super_stripesize(disk_super); |
| tree_root->nodesize = nodesize; |
| tree_root->leafsize = leafsize; |
| tree_root->sectorsize = sectorsize; |
| tree_root->stripesize = stripesize; |
| |
| sb->s_blocksize = sectorsize; |
| sb->s_blocksize_bits = blksize_bits(sectorsize); |
| |
| if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC, |
| sizeof(disk_super->magic))) { |
| printk("btrfs: valid FS not found on %s\n", sb->s_id); |
| goto fail_sb_buffer; |
| } |
| |
| mutex_lock(&fs_info->chunk_mutex); |
| ret = btrfs_read_sys_array(tree_root); |
| mutex_unlock(&fs_info->chunk_mutex); |
| if (ret) { |
| printk("btrfs: failed to read the system array on %s\n", |
| sb->s_id); |
| goto fail_sys_array; |
| } |
| |
| blocksize = btrfs_level_size(tree_root, |
| btrfs_super_chunk_root_level(disk_super)); |
| |
| __setup_root(nodesize, leafsize, sectorsize, stripesize, |
| chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID); |
| |
| chunk_root->node = read_tree_block(chunk_root, |
| btrfs_super_chunk_root(disk_super), |
| blocksize, 0); |
| BUG_ON(!chunk_root->node); |
| |
| read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid, |
| (unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node), |
| BTRFS_UUID_SIZE); |
| |
| mutex_lock(&fs_info->chunk_mutex); |
| ret = btrfs_read_chunk_tree(chunk_root); |
| mutex_unlock(&fs_info->chunk_mutex); |
| BUG_ON(ret); |
| |
| btrfs_close_extra_devices(fs_devices); |
| |
| blocksize = btrfs_level_size(tree_root, |
| btrfs_super_root_level(disk_super)); |
| |
| |
| tree_root->node = read_tree_block(tree_root, |
| btrfs_super_root(disk_super), |
| blocksize, 0); |
| if (!tree_root->node) |
| goto fail_sb_buffer; |
| |
| |
| ret = find_and_setup_root(tree_root, fs_info, |
| BTRFS_EXTENT_TREE_OBJECTID, extent_root); |
| if (ret) |
| goto fail_tree_root; |
| extent_root->track_dirty = 1; |
| |
| ret = find_and_setup_root(tree_root, fs_info, |
| BTRFS_DEV_TREE_OBJECTID, dev_root); |
| dev_root->track_dirty = 1; |
| |
| if (ret) |
| goto fail_extent_root; |
| |
| btrfs_read_block_groups(extent_root); |
| |
| fs_info->generation = btrfs_super_generation(disk_super) + 1; |
| fs_info->data_alloc_profile = (u64)-1; |
| fs_info->metadata_alloc_profile = (u64)-1; |
| fs_info->system_alloc_profile = fs_info->metadata_alloc_profile; |
| fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root, |
| "btrfs-cleaner"); |
| if (!fs_info->cleaner_kthread) |
| goto fail_extent_root; |
| |
| fs_info->transaction_kthread = kthread_run(transaction_kthread, |
| tree_root, |
| "btrfs-transaction"); |
| if (!fs_info->transaction_kthread) |
| goto fail_cleaner; |
| |
| if (btrfs_super_log_root(disk_super) != 0) { |
| u32 blocksize; |
| u64 bytenr = btrfs_super_log_root(disk_super); |
| |
| blocksize = |
| btrfs_level_size(tree_root, |
| btrfs_super_log_root_level(disk_super)); |
| |
| log_tree_root = kzalloc(sizeof(struct btrfs_root), |
| GFP_NOFS); |
| |
| __setup_root(nodesize, leafsize, sectorsize, stripesize, |
| log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID); |
| |
| log_tree_root->node = read_tree_block(tree_root, bytenr, |
| blocksize, 0); |
| ret = btrfs_recover_log_trees(log_tree_root); |
| BUG_ON(ret); |
| } |
| fs_info->last_trans_committed = btrfs_super_generation(disk_super); |
| return tree_root; |
| |
| fail_cleaner: |
| kthread_stop(fs_info->cleaner_kthread); |
| fail_extent_root: |
| free_extent_buffer(extent_root->node); |
| fail_tree_root: |
| free_extent_buffer(tree_root->node); |
| fail_sys_array: |
| fail_sb_buffer: |
| btrfs_stop_workers(&fs_info->fixup_workers); |
| btrfs_stop_workers(&fs_info->workers); |
| btrfs_stop_workers(&fs_info->endio_workers); |
| btrfs_stop_workers(&fs_info->endio_write_workers); |
| btrfs_stop_workers(&fs_info->submit_workers); |
| fail_iput: |
| iput(fs_info->btree_inode); |
| fail: |
| btrfs_close_devices(fs_info->fs_devices); |
| btrfs_mapping_tree_free(&fs_info->mapping_tree); |
| |
| kfree(extent_root); |
| kfree(tree_root); |
| #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| bdi_destroy(&fs_info->bdi); |
| #endif |
| kfree(fs_info); |
| return ERR_PTR(err); |
| } |
| |
| static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate) |
| { |
| char b[BDEVNAME_SIZE]; |
| |
| if (uptodate) { |
| set_buffer_uptodate(bh); |
| } else { |
| if (!buffer_eopnotsupp(bh) && printk_ratelimit()) { |
| printk(KERN_WARNING "lost page write due to " |
| "I/O error on %s\n", |
| bdevname(bh->b_bdev, b)); |
| } |
| /* note, we dont' set_buffer_write_io_error because we have |
| * our own ways of dealing with the IO errors |
| */ |
| clear_buffer_uptodate(bh); |
| } |
| unlock_buffer(bh); |
| put_bh(bh); |
| } |
| |
| int write_all_supers(struct btrfs_root *root) |
| { |
| struct list_head *cur; |
| struct list_head *head = &root->fs_info->fs_devices->devices; |
| struct btrfs_device *dev; |
| struct btrfs_super_block *sb; |
| struct btrfs_dev_item *dev_item; |
| struct buffer_head *bh; |
| int ret; |
| int do_barriers; |
| int max_errors; |
| int total_errors = 0; |
| u32 crc; |
| u64 flags; |
| |
| max_errors = btrfs_super_num_devices(&root->fs_info->super_copy) - 1; |
| do_barriers = !btrfs_test_opt(root, NOBARRIER); |
| |
| sb = &root->fs_info->super_for_commit; |
| dev_item = &sb->dev_item; |
| list_for_each(cur, head) { |
| dev = list_entry(cur, struct btrfs_device, dev_list); |
| if (!dev->bdev) { |
| total_errors++; |
| continue; |
| } |
| if (!dev->in_fs_metadata) |
| continue; |
| |
| btrfs_set_stack_device_type(dev_item, dev->type); |
| btrfs_set_stack_device_id(dev_item, dev->devid); |
| btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes); |
| btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used); |
| btrfs_set_stack_device_io_align(dev_item, dev->io_align); |
| btrfs_set_stack_device_io_width(dev_item, dev->io_width); |
| btrfs_set_stack_device_sector_size(dev_item, dev->sector_size); |
| memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE); |
| flags = btrfs_super_flags(sb); |
| btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN); |
| |
| |
| crc = ~(u32)0; |
| crc = btrfs_csum_data(root, (char *)sb + BTRFS_CSUM_SIZE, crc, |
| BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE); |
| btrfs_csum_final(crc, sb->csum); |
| |
| bh = __getblk(dev->bdev, BTRFS_SUPER_INFO_OFFSET / 4096, |
| BTRFS_SUPER_INFO_SIZE); |
| |
| memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE); |
| dev->pending_io = bh; |
| |
| get_bh(bh); |
| set_buffer_uptodate(bh); |
| lock_buffer(bh); |
| bh->b_end_io = btrfs_end_buffer_write_sync; |
| |
| if (do_barriers && dev->barriers) { |
| ret = submit_bh(WRITE_BARRIER, bh); |
| if (ret == -EOPNOTSUPP) { |
| printk("btrfs: disabling barriers on dev %s\n", |
| dev->name); |
| set_buffer_uptodate(bh); |
| dev->barriers = 0; |
| get_bh(bh); |
| lock_buffer(bh); |
| ret = submit_bh(WRITE, bh); |
| } |
| } else { |
| ret = submit_bh(WRITE, bh); |
| } |
| if (ret) |
| total_errors++; |
| } |
| if (total_errors > max_errors) { |
| printk("btrfs: %d errors while writing supers\n", total_errors); |
| BUG(); |
| } |
| total_errors = 0; |
| |
| list_for_each(cur, head) { |
| dev = list_entry(cur, struct btrfs_device, dev_list); |
| if (!dev->bdev) |
| continue; |
| if (!dev->in_fs_metadata) |
| continue; |
| |
| BUG_ON(!dev->pending_io); |
| bh = dev->pending_io; |
| wait_on_buffer(bh); |
| if (!buffer_uptodate(dev->pending_io)) { |
| if (do_barriers && dev->barriers) { |
| printk("btrfs: disabling barriers on dev %s\n", |
| dev->name); |
| set_buffer_uptodate(bh); |
| get_bh(bh); |
| lock_buffer(bh); |
| dev->barriers = 0; |
| ret = submit_bh(WRITE, bh); |
| BUG_ON(ret); |
| wait_on_buffer(bh); |
| if (!buffer_uptodate(bh)) |
| total_errors++; |
| } else { |
| total_errors++; |
| } |
| |
| } |
| dev->pending_io = NULL; |
| brelse(bh); |
| } |
| if (total_errors > max_errors) { |
| printk("btrfs: %d errors while writing supers\n", total_errors); |
| BUG(); |
| } |
| return 0; |
| } |
| |
| int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root |
| *root) |
| { |
| int ret; |
| |
| ret = write_all_supers(root); |
| return ret; |
| } |
| |
| int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root) |
| { |
| radix_tree_delete(&fs_info->fs_roots_radix, |
| (unsigned long)root->root_key.objectid); |
| if (root->in_sysfs) |
| btrfs_sysfs_del_root(root); |
| if (root->inode) |
| iput(root->inode); |
| if (root->node) |
| free_extent_buffer(root->node); |
| if (root->commit_root) |
| free_extent_buffer(root->commit_root); |
| if (root->name) |
| kfree(root->name); |
| kfree(root); |
| return 0; |
| } |
| |
| static int del_fs_roots(struct btrfs_fs_info *fs_info) |
| { |
| int ret; |
| struct btrfs_root *gang[8]; |
| int i; |
| |
| while(1) { |
| ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix, |
| (void **)gang, 0, |
| ARRAY_SIZE(gang)); |
| if (!ret) |
| break; |
| for (i = 0; i < ret; i++) |
| btrfs_free_fs_root(fs_info, gang[i]); |
| } |
| return 0; |
| } |
| |
| int close_ctree(struct btrfs_root *root) |
| { |
| int ret; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| |
| fs_info->closing = 1; |
| smp_mb(); |
| |
| kthread_stop(root->fs_info->transaction_kthread); |
| kthread_stop(root->fs_info->cleaner_kthread); |
| |
| btrfs_clean_old_snapshots(root); |
| trans = btrfs_start_transaction(root, 1); |
| ret = btrfs_commit_transaction(trans, root); |
| /* run commit again to drop the original snapshot */ |
| trans = btrfs_start_transaction(root, 1); |
| btrfs_commit_transaction(trans, root); |
| ret = btrfs_write_and_wait_transaction(NULL, root); |
| BUG_ON(ret); |
| |
| write_ctree_super(NULL, root); |
| |
| if (fs_info->delalloc_bytes) { |
| printk("btrfs: at unmount delalloc count %Lu\n", |
| fs_info->delalloc_bytes); |
| } |
| if (fs_info->total_ref_cache_size) { |
| printk("btrfs: at umount reference cache size %Lu\n", |
| fs_info->total_ref_cache_size); |
| } |
| |
| if (fs_info->extent_root->node) |
| free_extent_buffer(fs_info->extent_root->node); |
| |
| if (fs_info->tree_root->node) |
| free_extent_buffer(fs_info->tree_root->node); |
| |
| if (root->fs_info->chunk_root->node); |
| free_extent_buffer(root->fs_info->chunk_root->node); |
| |
| if (root->fs_info->dev_root->node); |
| free_extent_buffer(root->fs_info->dev_root->node); |
| |
| btrfs_free_block_groups(root->fs_info); |
| fs_info->closing = 2; |
| del_fs_roots(fs_info); |
| |
| filemap_write_and_wait(fs_info->btree_inode->i_mapping); |
| |
| truncate_inode_pages(fs_info->btree_inode->i_mapping, 0); |
| |
| btrfs_stop_workers(&fs_info->fixup_workers); |
| btrfs_stop_workers(&fs_info->workers); |
| btrfs_stop_workers(&fs_info->endio_workers); |
| btrfs_stop_workers(&fs_info->endio_write_workers); |
| btrfs_stop_workers(&fs_info->submit_workers); |
| |
| iput(fs_info->btree_inode); |
| #if 0 |
| while(!list_empty(&fs_info->hashers)) { |
| struct btrfs_hasher *hasher; |
| hasher = list_entry(fs_info->hashers.next, struct btrfs_hasher, |
| hashers); |
| list_del(&hasher->hashers); |
| crypto_free_hash(&fs_info->hash_tfm); |
| kfree(hasher); |
| } |
| #endif |
| btrfs_close_devices(fs_info->fs_devices); |
| btrfs_mapping_tree_free(&fs_info->mapping_tree); |
| |
| #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23) |
| bdi_destroy(&fs_info->bdi); |
| #endif |
| |
| kfree(fs_info->extent_root); |
| kfree(fs_info->tree_root); |
| kfree(fs_info->chunk_root); |
| kfree(fs_info->dev_root); |
| return 0; |
| } |
| |
| int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid) |
| { |
| int ret; |
| struct inode *btree_inode = buf->first_page->mapping->host; |
| |
| ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf); |
| if (!ret) |
| return ret; |
| |
| ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf, |
| parent_transid); |
| return !ret; |
| } |
| |
| int btrfs_set_buffer_uptodate(struct extent_buffer *buf) |
| { |
| struct inode *btree_inode = buf->first_page->mapping->host; |
| return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, |
| buf); |
| } |
| |
| void btrfs_mark_buffer_dirty(struct extent_buffer *buf) |
| { |
| struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root; |
| u64 transid = btrfs_header_generation(buf); |
| struct inode *btree_inode = root->fs_info->btree_inode; |
| |
| WARN_ON(!btrfs_tree_locked(buf)); |
| if (transid != root->fs_info->generation) { |
| printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n", |
| (unsigned long long)buf->start, |
| transid, root->fs_info->generation); |
| WARN_ON(1); |
| } |
| set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree, buf); |
| } |
| |
| void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr) |
| { |
| /* |
| * looks as though older kernels can get into trouble with |
| * this code, they end up stuck in balance_dirty_pages forever |
| */ |
| struct extent_io_tree *tree; |
| u64 num_dirty; |
| u64 start = 0; |
| unsigned long thresh = 96 * 1024 * 1024; |
| tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree; |
| |
| if (current_is_pdflush() || current->flags & PF_MEMALLOC) |
| return; |
| |
| num_dirty = count_range_bits(tree, &start, (u64)-1, |
| thresh, EXTENT_DIRTY); |
| if (num_dirty > thresh) { |
| balance_dirty_pages_ratelimited_nr( |
| root->fs_info->btree_inode->i_mapping, 1); |
| } |
| return; |
| } |
| |
| int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid) |
| { |
| struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root; |
| int ret; |
| ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid); |
| if (ret == 0) { |
| buf->flags |= EXTENT_UPTODATE; |
| } |
| return ret; |
| } |
| |
| int btree_lock_page_hook(struct page *page) |
| { |
| struct inode *inode = page->mapping->host; |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; |
| struct extent_buffer *eb; |
| unsigned long len; |
| u64 bytenr = page_offset(page); |
| |
| if (page->private == EXTENT_PAGE_PRIVATE) |
| goto out; |
| |
| len = page->private >> 2; |
| eb = find_extent_buffer(io_tree, bytenr, len, GFP_NOFS); |
| if (!eb) |
| goto out; |
| |
| btrfs_tree_lock(eb); |
| spin_lock(&root->fs_info->hash_lock); |
| btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN); |
| spin_unlock(&root->fs_info->hash_lock); |
| btrfs_tree_unlock(eb); |
| free_extent_buffer(eb); |
| out: |
| lock_page(page); |
| return 0; |
| } |
| |
| static struct extent_io_ops btree_extent_io_ops = { |
| .write_cache_pages_lock_hook = btree_lock_page_hook, |
| .readpage_end_io_hook = btree_readpage_end_io_hook, |
| .submit_bio_hook = btree_submit_bio_hook, |
| /* note we're sharing with inode.c for the merge bio hook */ |
| .merge_bio_hook = btrfs_merge_bio_hook, |
| }; |