| /* |
| * Copyright (C) 2008 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/sched.h> |
| #include <linux/slab.h> |
| #include "ctree.h" |
| #include "transaction.h" |
| #include "disk-io.h" |
| #include "locking.h" |
| #include "print-tree.h" |
| #include "compat.h" |
| #include "tree-log.h" |
| |
| /* magic values for the inode_only field in btrfs_log_inode: |
| * |
| * LOG_INODE_ALL means to log everything |
| * LOG_INODE_EXISTS means to log just enough to recreate the inode |
| * during log replay |
| */ |
| #define LOG_INODE_ALL 0 |
| #define LOG_INODE_EXISTS 1 |
| |
| /* |
| * directory trouble cases |
| * |
| * 1) on rename or unlink, if the inode being unlinked isn't in the fsync |
| * log, we must force a full commit before doing an fsync of the directory |
| * where the unlink was done. |
| * ---> record transid of last unlink/rename per directory |
| * |
| * mkdir foo/some_dir |
| * normal commit |
| * rename foo/some_dir foo2/some_dir |
| * mkdir foo/some_dir |
| * fsync foo/some_dir/some_file |
| * |
| * The fsync above will unlink the original some_dir without recording |
| * it in its new location (foo2). After a crash, some_dir will be gone |
| * unless the fsync of some_file forces a full commit |
| * |
| * 2) we must log any new names for any file or dir that is in the fsync |
| * log. ---> check inode while renaming/linking. |
| * |
| * 2a) we must log any new names for any file or dir during rename |
| * when the directory they are being removed from was logged. |
| * ---> check inode and old parent dir during rename |
| * |
| * 2a is actually the more important variant. With the extra logging |
| * a crash might unlink the old name without recreating the new one |
| * |
| * 3) after a crash, we must go through any directories with a link count |
| * of zero and redo the rm -rf |
| * |
| * mkdir f1/foo |
| * normal commit |
| * rm -rf f1/foo |
| * fsync(f1) |
| * |
| * The directory f1 was fully removed from the FS, but fsync was never |
| * called on f1, only its parent dir. After a crash the rm -rf must |
| * be replayed. This must be able to recurse down the entire |
| * directory tree. The inode link count fixup code takes care of the |
| * ugly details. |
| */ |
| |
| /* |
| * stages for the tree walking. The first |
| * stage (0) is to only pin down the blocks we find |
| * the second stage (1) is to make sure that all the inodes |
| * we find in the log are created in the subvolume. |
| * |
| * The last stage is to deal with directories and links and extents |
| * and all the other fun semantics |
| */ |
| #define LOG_WALK_PIN_ONLY 0 |
| #define LOG_WALK_REPLAY_INODES 1 |
| #define LOG_WALK_REPLAY_ALL 2 |
| |
| static int btrfs_log_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| int inode_only); |
| static int link_to_fixup_dir(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, u64 objectid); |
| static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| u64 dirid, int del_all); |
| |
| /* |
| * tree logging is a special write ahead log used to make sure that |
| * fsyncs and O_SYNCs can happen without doing full tree commits. |
| * |
| * Full tree commits are expensive because they require commonly |
| * modified blocks to be recowed, creating many dirty pages in the |
| * extent tree an 4x-6x higher write load than ext3. |
| * |
| * Instead of doing a tree commit on every fsync, we use the |
| * key ranges and transaction ids to find items for a given file or directory |
| * that have changed in this transaction. Those items are copied into |
| * a special tree (one per subvolume root), that tree is written to disk |
| * and then the fsync is considered complete. |
| * |
| * After a crash, items are copied out of the log-tree back into the |
| * subvolume tree. Any file data extents found are recorded in the extent |
| * allocation tree, and the log-tree freed. |
| * |
| * The log tree is read three times, once to pin down all the extents it is |
| * using in ram and once, once to create all the inodes logged in the tree |
| * and once to do all the other items. |
| */ |
| |
| /* |
| * start a sub transaction and setup the log tree |
| * this increments the log tree writer count to make the people |
| * syncing the tree wait for us to finish |
| */ |
| static int start_log_trans(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root) |
| { |
| int ret; |
| int err = 0; |
| |
| mutex_lock(&root->log_mutex); |
| if (root->log_root) { |
| if (!root->log_start_pid) { |
| root->log_start_pid = current->pid; |
| root->log_multiple_pids = false; |
| } else if (root->log_start_pid != current->pid) { |
| root->log_multiple_pids = true; |
| } |
| |
| root->log_batch++; |
| atomic_inc(&root->log_writers); |
| mutex_unlock(&root->log_mutex); |
| return 0; |
| } |
| root->log_multiple_pids = false; |
| root->log_start_pid = current->pid; |
| mutex_lock(&root->fs_info->tree_log_mutex); |
| if (!root->fs_info->log_root_tree) { |
| ret = btrfs_init_log_root_tree(trans, root->fs_info); |
| if (ret) |
| err = ret; |
| } |
| if (err == 0 && !root->log_root) { |
| ret = btrfs_add_log_tree(trans, root); |
| if (ret) |
| err = ret; |
| } |
| mutex_unlock(&root->fs_info->tree_log_mutex); |
| root->log_batch++; |
| atomic_inc(&root->log_writers); |
| mutex_unlock(&root->log_mutex); |
| return err; |
| } |
| |
| /* |
| * returns 0 if there was a log transaction running and we were able |
| * to join, or returns -ENOENT if there were not transactions |
| * in progress |
| */ |
| static int join_running_log_trans(struct btrfs_root *root) |
| { |
| int ret = -ENOENT; |
| |
| smp_mb(); |
| if (!root->log_root) |
| return -ENOENT; |
| |
| mutex_lock(&root->log_mutex); |
| if (root->log_root) { |
| ret = 0; |
| atomic_inc(&root->log_writers); |
| } |
| mutex_unlock(&root->log_mutex); |
| return ret; |
| } |
| |
| /* |
| * This either makes the current running log transaction wait |
| * until you call btrfs_end_log_trans() or it makes any future |
| * log transactions wait until you call btrfs_end_log_trans() |
| */ |
| int btrfs_pin_log_trans(struct btrfs_root *root) |
| { |
| int ret = -ENOENT; |
| |
| mutex_lock(&root->log_mutex); |
| atomic_inc(&root->log_writers); |
| mutex_unlock(&root->log_mutex); |
| return ret; |
| } |
| |
| /* |
| * indicate we're done making changes to the log tree |
| * and wake up anyone waiting to do a sync |
| */ |
| int btrfs_end_log_trans(struct btrfs_root *root) |
| { |
| if (atomic_dec_and_test(&root->log_writers)) { |
| smp_mb(); |
| if (waitqueue_active(&root->log_writer_wait)) |
| wake_up(&root->log_writer_wait); |
| } |
| return 0; |
| } |
| |
| |
| /* |
| * the walk control struct is used to pass state down the chain when |
| * processing the log tree. The stage field tells us which part |
| * of the log tree processing we are currently doing. The others |
| * are state fields used for that specific part |
| */ |
| struct walk_control { |
| /* should we free the extent on disk when done? This is used |
| * at transaction commit time while freeing a log tree |
| */ |
| int free; |
| |
| /* should we write out the extent buffer? This is used |
| * while flushing the log tree to disk during a sync |
| */ |
| int write; |
| |
| /* should we wait for the extent buffer io to finish? Also used |
| * while flushing the log tree to disk for a sync |
| */ |
| int wait; |
| |
| /* pin only walk, we record which extents on disk belong to the |
| * log trees |
| */ |
| int pin; |
| |
| /* what stage of the replay code we're currently in */ |
| int stage; |
| |
| /* the root we are currently replaying */ |
| struct btrfs_root *replay_dest; |
| |
| /* the trans handle for the current replay */ |
| struct btrfs_trans_handle *trans; |
| |
| /* the function that gets used to process blocks we find in the |
| * tree. Note the extent_buffer might not be up to date when it is |
| * passed in, and it must be checked or read if you need the data |
| * inside it |
| */ |
| int (*process_func)(struct btrfs_root *log, struct extent_buffer *eb, |
| struct walk_control *wc, u64 gen); |
| }; |
| |
| /* |
| * process_func used to pin down extents, write them or wait on them |
| */ |
| static int process_one_buffer(struct btrfs_root *log, |
| struct extent_buffer *eb, |
| struct walk_control *wc, u64 gen) |
| { |
| if (wc->pin) |
| btrfs_pin_extent(log->fs_info->extent_root, |
| eb->start, eb->len, 0); |
| |
| if (btrfs_buffer_uptodate(eb, gen)) { |
| if (wc->write) |
| btrfs_write_tree_block(eb); |
| if (wc->wait) |
| btrfs_wait_tree_block_writeback(eb); |
| } |
| return 0; |
| } |
| |
| /* |
| * Item overwrite used by replay and tree logging. eb, slot and key all refer |
| * to the src data we are copying out. |
| * |
| * root is the tree we are copying into, and path is a scratch |
| * path for use in this function (it should be released on entry and |
| * will be released on exit). |
| * |
| * If the key is already in the destination tree the existing item is |
| * overwritten. If the existing item isn't big enough, it is extended. |
| * If it is too large, it is truncated. |
| * |
| * If the key isn't in the destination yet, a new item is inserted. |
| */ |
| static noinline int overwrite_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct extent_buffer *eb, int slot, |
| struct btrfs_key *key) |
| { |
| int ret; |
| u32 item_size; |
| u64 saved_i_size = 0; |
| int save_old_i_size = 0; |
| unsigned long src_ptr; |
| unsigned long dst_ptr; |
| int overwrite_root = 0; |
| |
| if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) |
| overwrite_root = 1; |
| |
| item_size = btrfs_item_size_nr(eb, slot); |
| src_ptr = btrfs_item_ptr_offset(eb, slot); |
| |
| /* look for the key in the destination tree */ |
| ret = btrfs_search_slot(NULL, root, key, path, 0, 0); |
| if (ret == 0) { |
| char *src_copy; |
| char *dst_copy; |
| u32 dst_size = btrfs_item_size_nr(path->nodes[0], |
| path->slots[0]); |
| if (dst_size != item_size) |
| goto insert; |
| |
| if (item_size == 0) { |
| btrfs_release_path(path); |
| return 0; |
| } |
| dst_copy = kmalloc(item_size, GFP_NOFS); |
| src_copy = kmalloc(item_size, GFP_NOFS); |
| if (!dst_copy || !src_copy) { |
| btrfs_release_path(path); |
| kfree(dst_copy); |
| kfree(src_copy); |
| return -ENOMEM; |
| } |
| |
| read_extent_buffer(eb, src_copy, src_ptr, item_size); |
| |
| dst_ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]); |
| read_extent_buffer(path->nodes[0], dst_copy, dst_ptr, |
| item_size); |
| ret = memcmp(dst_copy, src_copy, item_size); |
| |
| kfree(dst_copy); |
| kfree(src_copy); |
| /* |
| * they have the same contents, just return, this saves |
| * us from cowing blocks in the destination tree and doing |
| * extra writes that may not have been done by a previous |
| * sync |
| */ |
| if (ret == 0) { |
| btrfs_release_path(path); |
| return 0; |
| } |
| |
| } |
| insert: |
| btrfs_release_path(path); |
| /* try to insert the key into the destination tree */ |
| ret = btrfs_insert_empty_item(trans, root, path, |
| key, item_size); |
| |
| /* make sure any existing item is the correct size */ |
| if (ret == -EEXIST) { |
| u32 found_size; |
| found_size = btrfs_item_size_nr(path->nodes[0], |
| path->slots[0]); |
| if (found_size > item_size) { |
| btrfs_truncate_item(trans, root, path, item_size, 1); |
| } else if (found_size < item_size) { |
| ret = btrfs_extend_item(trans, root, path, |
| item_size - found_size); |
| } |
| } else if (ret) { |
| return ret; |
| } |
| dst_ptr = btrfs_item_ptr_offset(path->nodes[0], |
| path->slots[0]); |
| |
| /* don't overwrite an existing inode if the generation number |
| * was logged as zero. This is done when the tree logging code |
| * is just logging an inode to make sure it exists after recovery. |
| * |
| * Also, don't overwrite i_size on directories during replay. |
| * log replay inserts and removes directory items based on the |
| * state of the tree found in the subvolume, and i_size is modified |
| * as it goes |
| */ |
| if (key->type == BTRFS_INODE_ITEM_KEY && ret == -EEXIST) { |
| struct btrfs_inode_item *src_item; |
| struct btrfs_inode_item *dst_item; |
| |
| src_item = (struct btrfs_inode_item *)src_ptr; |
| dst_item = (struct btrfs_inode_item *)dst_ptr; |
| |
| if (btrfs_inode_generation(eb, src_item) == 0) |
| goto no_copy; |
| |
| if (overwrite_root && |
| S_ISDIR(btrfs_inode_mode(eb, src_item)) && |
| S_ISDIR(btrfs_inode_mode(path->nodes[0], dst_item))) { |
| save_old_i_size = 1; |
| saved_i_size = btrfs_inode_size(path->nodes[0], |
| dst_item); |
| } |
| } |
| |
| copy_extent_buffer(path->nodes[0], eb, dst_ptr, |
| src_ptr, item_size); |
| |
| if (save_old_i_size) { |
| struct btrfs_inode_item *dst_item; |
| dst_item = (struct btrfs_inode_item *)dst_ptr; |
| btrfs_set_inode_size(path->nodes[0], dst_item, saved_i_size); |
| } |
| |
| /* make sure the generation is filled in */ |
| if (key->type == BTRFS_INODE_ITEM_KEY) { |
| struct btrfs_inode_item *dst_item; |
| dst_item = (struct btrfs_inode_item *)dst_ptr; |
| if (btrfs_inode_generation(path->nodes[0], dst_item) == 0) { |
| btrfs_set_inode_generation(path->nodes[0], dst_item, |
| trans->transid); |
| } |
| } |
| no_copy: |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| btrfs_release_path(path); |
| return 0; |
| } |
| |
| /* |
| * simple helper to read an inode off the disk from a given root |
| * This can only be called for subvolume roots and not for the log |
| */ |
| static noinline struct inode *read_one_inode(struct btrfs_root *root, |
| u64 objectid) |
| { |
| struct btrfs_key key; |
| struct inode *inode; |
| |
| key.objectid = objectid; |
| key.type = BTRFS_INODE_ITEM_KEY; |
| key.offset = 0; |
| inode = btrfs_iget(root->fs_info->sb, &key, root, NULL); |
| if (IS_ERR(inode)) { |
| inode = NULL; |
| } else if (is_bad_inode(inode)) { |
| iput(inode); |
| inode = NULL; |
| } |
| return inode; |
| } |
| |
| /* replays a single extent in 'eb' at 'slot' with 'key' into the |
| * subvolume 'root'. path is released on entry and should be released |
| * on exit. |
| * |
| * extents in the log tree have not been allocated out of the extent |
| * tree yet. So, this completes the allocation, taking a reference |
| * as required if the extent already exists or creating a new extent |
| * if it isn't in the extent allocation tree yet. |
| * |
| * The extent is inserted into the file, dropping any existing extents |
| * from the file that overlap the new one. |
| */ |
| static noinline int replay_one_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct extent_buffer *eb, int slot, |
| struct btrfs_key *key) |
| { |
| int found_type; |
| u64 mask = root->sectorsize - 1; |
| u64 extent_end; |
| u64 alloc_hint; |
| u64 start = key->offset; |
| u64 saved_nbytes; |
| struct btrfs_file_extent_item *item; |
| struct inode *inode = NULL; |
| unsigned long size; |
| int ret = 0; |
| |
| item = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item); |
| found_type = btrfs_file_extent_type(eb, item); |
| |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) |
| extent_end = start + btrfs_file_extent_num_bytes(eb, item); |
| else if (found_type == BTRFS_FILE_EXTENT_INLINE) { |
| size = btrfs_file_extent_inline_len(eb, item); |
| extent_end = (start + size + mask) & ~mask; |
| } else { |
| ret = 0; |
| goto out; |
| } |
| |
| inode = read_one_inode(root, key->objectid); |
| if (!inode) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| /* |
| * first check to see if we already have this extent in the |
| * file. This must be done before the btrfs_drop_extents run |
| * so we don't try to drop this extent. |
| */ |
| ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode), |
| start, 0); |
| |
| if (ret == 0 && |
| (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC)) { |
| struct btrfs_file_extent_item cmp1; |
| struct btrfs_file_extent_item cmp2; |
| struct btrfs_file_extent_item *existing; |
| struct extent_buffer *leaf; |
| |
| leaf = path->nodes[0]; |
| existing = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| |
| read_extent_buffer(eb, &cmp1, (unsigned long)item, |
| sizeof(cmp1)); |
| read_extent_buffer(leaf, &cmp2, (unsigned long)existing, |
| sizeof(cmp2)); |
| |
| /* |
| * we already have a pointer to this exact extent, |
| * we don't have to do anything |
| */ |
| if (memcmp(&cmp1, &cmp2, sizeof(cmp1)) == 0) { |
| btrfs_release_path(path); |
| goto out; |
| } |
| } |
| btrfs_release_path(path); |
| |
| saved_nbytes = inode_get_bytes(inode); |
| /* drop any overlapping extents */ |
| ret = btrfs_drop_extents(trans, inode, start, extent_end, |
| &alloc_hint, 1); |
| BUG_ON(ret); |
| |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| u64 offset; |
| unsigned long dest_offset; |
| struct btrfs_key ins; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, key, |
| sizeof(*item)); |
| BUG_ON(ret); |
| dest_offset = btrfs_item_ptr_offset(path->nodes[0], |
| path->slots[0]); |
| copy_extent_buffer(path->nodes[0], eb, dest_offset, |
| (unsigned long)item, sizeof(*item)); |
| |
| ins.objectid = btrfs_file_extent_disk_bytenr(eb, item); |
| ins.offset = btrfs_file_extent_disk_num_bytes(eb, item); |
| ins.type = BTRFS_EXTENT_ITEM_KEY; |
| offset = key->offset - btrfs_file_extent_offset(eb, item); |
| |
| if (ins.objectid > 0) { |
| u64 csum_start; |
| u64 csum_end; |
| LIST_HEAD(ordered_sums); |
| /* |
| * is this extent already allocated in the extent |
| * allocation tree? If so, just add a reference |
| */ |
| ret = btrfs_lookup_extent(root, ins.objectid, |
| ins.offset); |
| if (ret == 0) { |
| ret = btrfs_inc_extent_ref(trans, root, |
| ins.objectid, ins.offset, |
| 0, root->root_key.objectid, |
| key->objectid, offset); |
| BUG_ON(ret); |
| } else { |
| /* |
| * insert the extent pointer in the extent |
| * allocation tree |
| */ |
| ret = btrfs_alloc_logged_file_extent(trans, |
| root, root->root_key.objectid, |
| key->objectid, offset, &ins); |
| BUG_ON(ret); |
| } |
| btrfs_release_path(path); |
| |
| if (btrfs_file_extent_compression(eb, item)) { |
| csum_start = ins.objectid; |
| csum_end = csum_start + ins.offset; |
| } else { |
| csum_start = ins.objectid + |
| btrfs_file_extent_offset(eb, item); |
| csum_end = csum_start + |
| btrfs_file_extent_num_bytes(eb, item); |
| } |
| |
| ret = btrfs_lookup_csums_range(root->log_root, |
| csum_start, csum_end - 1, |
| &ordered_sums, 0); |
| BUG_ON(ret); |
| while (!list_empty(&ordered_sums)) { |
| struct btrfs_ordered_sum *sums; |
| sums = list_entry(ordered_sums.next, |
| struct btrfs_ordered_sum, |
| list); |
| ret = btrfs_csum_file_blocks(trans, |
| root->fs_info->csum_root, |
| sums); |
| BUG_ON(ret); |
| list_del(&sums->list); |
| kfree(sums); |
| } |
| } else { |
| btrfs_release_path(path); |
| } |
| } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { |
| /* inline extents are easy, we just overwrite them */ |
| ret = overwrite_item(trans, root, path, eb, slot, key); |
| BUG_ON(ret); |
| } |
| |
| inode_set_bytes(inode, saved_nbytes); |
| btrfs_update_inode(trans, root, inode); |
| out: |
| if (inode) |
| iput(inode); |
| return ret; |
| } |
| |
| /* |
| * when cleaning up conflicts between the directory names in the |
| * subvolume, directory names in the log and directory names in the |
| * inode back references, we may have to unlink inodes from directories. |
| * |
| * This is a helper function to do the unlink of a specific directory |
| * item |
| */ |
| static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct inode *dir, |
| struct btrfs_dir_item *di) |
| { |
| struct inode *inode; |
| char *name; |
| int name_len; |
| struct extent_buffer *leaf; |
| struct btrfs_key location; |
| int ret; |
| |
| leaf = path->nodes[0]; |
| |
| btrfs_dir_item_key_to_cpu(leaf, di, &location); |
| name_len = btrfs_dir_name_len(leaf, di); |
| name = kmalloc(name_len, GFP_NOFS); |
| if (!name) |
| return -ENOMEM; |
| |
| read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len); |
| btrfs_release_path(path); |
| |
| inode = read_one_inode(root, location.objectid); |
| if (!inode) { |
| kfree(name); |
| return -EIO; |
| } |
| |
| ret = link_to_fixup_dir(trans, root, path, location.objectid); |
| BUG_ON(ret); |
| |
| ret = btrfs_unlink_inode(trans, root, dir, inode, name, name_len); |
| BUG_ON(ret); |
| kfree(name); |
| |
| iput(inode); |
| return ret; |
| } |
| |
| /* |
| * helper function to see if a given name and sequence number found |
| * in an inode back reference are already in a directory and correctly |
| * point to this inode |
| */ |
| static noinline int inode_in_dir(struct btrfs_root *root, |
| struct btrfs_path *path, |
| u64 dirid, u64 objectid, u64 index, |
| const char *name, int name_len) |
| { |
| struct btrfs_dir_item *di; |
| struct btrfs_key location; |
| int match = 0; |
| |
| di = btrfs_lookup_dir_index_item(NULL, root, path, dirid, |
| index, name, name_len, 0); |
| if (di && !IS_ERR(di)) { |
| btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); |
| if (location.objectid != objectid) |
| goto out; |
| } else |
| goto out; |
| btrfs_release_path(path); |
| |
| di = btrfs_lookup_dir_item(NULL, root, path, dirid, name, name_len, 0); |
| if (di && !IS_ERR(di)) { |
| btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); |
| if (location.objectid != objectid) |
| goto out; |
| } else |
| goto out; |
| match = 1; |
| out: |
| btrfs_release_path(path); |
| return match; |
| } |
| |
| /* |
| * helper function to check a log tree for a named back reference in |
| * an inode. This is used to decide if a back reference that is |
| * found in the subvolume conflicts with what we find in the log. |
| * |
| * inode backreferences may have multiple refs in a single item, |
| * during replay we process one reference at a time, and we don't |
| * want to delete valid links to a file from the subvolume if that |
| * link is also in the log. |
| */ |
| static noinline int backref_in_log(struct btrfs_root *log, |
| struct btrfs_key *key, |
| char *name, int namelen) |
| { |
| struct btrfs_path *path; |
| struct btrfs_inode_ref *ref; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| unsigned long name_ptr; |
| int found_name_len; |
| int item_size; |
| int ret; |
| int match = 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| ret = btrfs_search_slot(NULL, log, key, path, 0, 0); |
| if (ret != 0) |
| goto out; |
| |
| item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); |
| ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]); |
| ptr_end = ptr + item_size; |
| while (ptr < ptr_end) { |
| ref = (struct btrfs_inode_ref *)ptr; |
| found_name_len = btrfs_inode_ref_name_len(path->nodes[0], ref); |
| if (found_name_len == namelen) { |
| name_ptr = (unsigned long)(ref + 1); |
| ret = memcmp_extent_buffer(path->nodes[0], name, |
| name_ptr, namelen); |
| if (ret == 0) { |
| match = 1; |
| goto out; |
| } |
| } |
| ptr = (unsigned long)(ref + 1) + found_name_len; |
| } |
| out: |
| btrfs_free_path(path); |
| return match; |
| } |
| |
| |
| /* |
| * replay one inode back reference item found in the log tree. |
| * eb, slot and key refer to the buffer and key found in the log tree. |
| * root is the destination we are replaying into, and path is for temp |
| * use by this function. (it should be released on return). |
| */ |
| static noinline int add_inode_ref(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| struct extent_buffer *eb, int slot, |
| struct btrfs_key *key) |
| { |
| struct btrfs_inode_ref *ref; |
| struct btrfs_dir_item *di; |
| struct inode *dir; |
| struct inode *inode; |
| unsigned long ref_ptr; |
| unsigned long ref_end; |
| char *name; |
| int namelen; |
| int ret; |
| int search_done = 0; |
| |
| /* |
| * it is possible that we didn't log all the parent directories |
| * for a given inode. If we don't find the dir, just don't |
| * copy the back ref in. The link count fixup code will take |
| * care of the rest |
| */ |
| dir = read_one_inode(root, key->offset); |
| if (!dir) |
| return -ENOENT; |
| |
| inode = read_one_inode(root, key->objectid); |
| if (!inode) { |
| iput(dir); |
| return -EIO; |
| } |
| |
| ref_ptr = btrfs_item_ptr_offset(eb, slot); |
| ref_end = ref_ptr + btrfs_item_size_nr(eb, slot); |
| |
| again: |
| ref = (struct btrfs_inode_ref *)ref_ptr; |
| |
| namelen = btrfs_inode_ref_name_len(eb, ref); |
| name = kmalloc(namelen, GFP_NOFS); |
| BUG_ON(!name); |
| |
| read_extent_buffer(eb, name, (unsigned long)(ref + 1), namelen); |
| |
| /* if we already have a perfect match, we're done */ |
| if (inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode), |
| btrfs_inode_ref_index(eb, ref), |
| name, namelen)) { |
| goto out; |
| } |
| |
| /* |
| * look for a conflicting back reference in the metadata. |
| * if we find one we have to unlink that name of the file |
| * before we add our new link. Later on, we overwrite any |
| * existing back reference, and we don't want to create |
| * dangling pointers in the directory. |
| */ |
| |
| if (search_done) |
| goto insert; |
| |
| ret = btrfs_search_slot(NULL, root, key, path, 0, 0); |
| if (ret == 0) { |
| char *victim_name; |
| int victim_name_len; |
| struct btrfs_inode_ref *victim_ref; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| struct extent_buffer *leaf = path->nodes[0]; |
| |
| /* are we trying to overwrite a back ref for the root directory |
| * if so, just jump out, we're done |
| */ |
| if (key->objectid == key->offset) |
| goto out_nowrite; |
| |
| /* check all the names in this back reference to see |
| * if they are in the log. if so, we allow them to stay |
| * otherwise they must be unlinked as a conflict |
| */ |
| ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); |
| ptr_end = ptr + btrfs_item_size_nr(leaf, path->slots[0]); |
| while (ptr < ptr_end) { |
| victim_ref = (struct btrfs_inode_ref *)ptr; |
| victim_name_len = btrfs_inode_ref_name_len(leaf, |
| victim_ref); |
| victim_name = kmalloc(victim_name_len, GFP_NOFS); |
| BUG_ON(!victim_name); |
| |
| read_extent_buffer(leaf, victim_name, |
| (unsigned long)(victim_ref + 1), |
| victim_name_len); |
| |
| if (!backref_in_log(log, key, victim_name, |
| victim_name_len)) { |
| btrfs_inc_nlink(inode); |
| btrfs_release_path(path); |
| |
| ret = btrfs_unlink_inode(trans, root, dir, |
| inode, victim_name, |
| victim_name_len); |
| } |
| kfree(victim_name); |
| ptr = (unsigned long)(victim_ref + 1) + victim_name_len; |
| } |
| BUG_ON(ret); |
| |
| /* |
| * NOTE: we have searched root tree and checked the |
| * coresponding ref, it does not need to check again. |
| */ |
| search_done = 1; |
| } |
| btrfs_release_path(path); |
| |
| /* look for a conflicting sequence number */ |
| di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir), |
| btrfs_inode_ref_index(eb, ref), |
| name, namelen, 0); |
| if (di && !IS_ERR(di)) { |
| ret = drop_one_dir_item(trans, root, path, dir, di); |
| BUG_ON(ret); |
| } |
| btrfs_release_path(path); |
| |
| /* look for a conflicing name */ |
| di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir), |
| name, namelen, 0); |
| if (di && !IS_ERR(di)) { |
| ret = drop_one_dir_item(trans, root, path, dir, di); |
| BUG_ON(ret); |
| } |
| btrfs_release_path(path); |
| |
| insert: |
| /* insert our name */ |
| ret = btrfs_add_link(trans, dir, inode, name, namelen, 0, |
| btrfs_inode_ref_index(eb, ref)); |
| BUG_ON(ret); |
| |
| btrfs_update_inode(trans, root, inode); |
| |
| out: |
| ref_ptr = (unsigned long)(ref + 1) + namelen; |
| kfree(name); |
| if (ref_ptr < ref_end) |
| goto again; |
| |
| /* finally write the back reference in the inode */ |
| ret = overwrite_item(trans, root, path, eb, slot, key); |
| BUG_ON(ret); |
| |
| out_nowrite: |
| btrfs_release_path(path); |
| iput(dir); |
| iput(inode); |
| return 0; |
| } |
| |
| static int insert_orphan_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, u64 offset) |
| { |
| int ret; |
| ret = btrfs_find_orphan_item(root, offset); |
| if (ret > 0) |
| ret = btrfs_insert_orphan_item(trans, root, offset); |
| return ret; |
| } |
| |
| |
| /* |
| * There are a few corners where the link count of the file can't |
| * be properly maintained during replay. So, instead of adding |
| * lots of complexity to the log code, we just scan the backrefs |
| * for any file that has been through replay. |
| * |
| * The scan will update the link count on the inode to reflect the |
| * number of back refs found. If it goes down to zero, the iput |
| * will free the inode. |
| */ |
| static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct inode *inode) |
| { |
| struct btrfs_path *path; |
| int ret; |
| struct btrfs_key key; |
| u64 nlink = 0; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| int name_len; |
| u64 ino = btrfs_ino(inode); |
| |
| key.objectid = ino; |
| key.type = BTRFS_INODE_REF_KEY; |
| key.offset = (u64)-1; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| while (1) { |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| break; |
| if (ret > 0) { |
| if (path->slots[0] == 0) |
| break; |
| path->slots[0]--; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &key, |
| path->slots[0]); |
| if (key.objectid != ino || |
| key.type != BTRFS_INODE_REF_KEY) |
| break; |
| ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]); |
| ptr_end = ptr + btrfs_item_size_nr(path->nodes[0], |
| path->slots[0]); |
| while (ptr < ptr_end) { |
| struct btrfs_inode_ref *ref; |
| |
| ref = (struct btrfs_inode_ref *)ptr; |
| name_len = btrfs_inode_ref_name_len(path->nodes[0], |
| ref); |
| ptr = (unsigned long)(ref + 1) + name_len; |
| nlink++; |
| } |
| |
| if (key.offset == 0) |
| break; |
| key.offset--; |
| btrfs_release_path(path); |
| } |
| btrfs_release_path(path); |
| if (nlink != inode->i_nlink) { |
| inode->i_nlink = nlink; |
| btrfs_update_inode(trans, root, inode); |
| } |
| BTRFS_I(inode)->index_cnt = (u64)-1; |
| |
| if (inode->i_nlink == 0) { |
| if (S_ISDIR(inode->i_mode)) { |
| ret = replay_dir_deletes(trans, root, NULL, path, |
| ino, 1); |
| BUG_ON(ret); |
| } |
| ret = insert_orphan_item(trans, root, ino); |
| BUG_ON(ret); |
| } |
| btrfs_free_path(path); |
| |
| return 0; |
| } |
| |
| static noinline int fixup_inode_link_counts(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path) |
| { |
| int ret; |
| struct btrfs_key key; |
| struct inode *inode; |
| |
| key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID; |
| key.type = BTRFS_ORPHAN_ITEM_KEY; |
| key.offset = (u64)-1; |
| while (1) { |
| ret = btrfs_search_slot(trans, root, &key, path, -1, 1); |
| if (ret < 0) |
| break; |
| |
| if (ret == 1) { |
| if (path->slots[0] == 0) |
| break; |
| path->slots[0]--; |
| } |
| |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| if (key.objectid != BTRFS_TREE_LOG_FIXUP_OBJECTID || |
| key.type != BTRFS_ORPHAN_ITEM_KEY) |
| break; |
| |
| ret = btrfs_del_item(trans, root, path); |
| if (ret) |
| goto out; |
| |
| btrfs_release_path(path); |
| inode = read_one_inode(root, key.offset); |
| if (!inode) |
| return -EIO; |
| |
| ret = fixup_inode_link_count(trans, root, inode); |
| BUG_ON(ret); |
| |
| iput(inode); |
| |
| /* |
| * fixup on a directory may create new entries, |
| * make sure we always look for the highset possible |
| * offset |
| */ |
| key.offset = (u64)-1; |
| } |
| ret = 0; |
| out: |
| btrfs_release_path(path); |
| return ret; |
| } |
| |
| |
| /* |
| * record a given inode in the fixup dir so we can check its link |
| * count when replay is done. The link count is incremented here |
| * so the inode won't go away until we check it |
| */ |
| static noinline int link_to_fixup_dir(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| u64 objectid) |
| { |
| struct btrfs_key key; |
| int ret = 0; |
| struct inode *inode; |
| |
| inode = read_one_inode(root, objectid); |
| if (!inode) |
| return -EIO; |
| |
| key.objectid = BTRFS_TREE_LOG_FIXUP_OBJECTID; |
| btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY); |
| key.offset = objectid; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, &key, 0); |
| |
| btrfs_release_path(path); |
| if (ret == 0) { |
| btrfs_inc_nlink(inode); |
| btrfs_update_inode(trans, root, inode); |
| } else if (ret == -EEXIST) { |
| ret = 0; |
| } else { |
| BUG(); |
| } |
| iput(inode); |
| |
| return ret; |
| } |
| |
| /* |
| * when replaying the log for a directory, we only insert names |
| * for inodes that actually exist. This means an fsync on a directory |
| * does not implicitly fsync all the new files in it |
| */ |
| static noinline int insert_one_name(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| u64 dirid, u64 index, |
| char *name, int name_len, u8 type, |
| struct btrfs_key *location) |
| { |
| struct inode *inode; |
| struct inode *dir; |
| int ret; |
| |
| inode = read_one_inode(root, location->objectid); |
| if (!inode) |
| return -ENOENT; |
| |
| dir = read_one_inode(root, dirid); |
| if (!dir) { |
| iput(inode); |
| return -EIO; |
| } |
| ret = btrfs_add_link(trans, dir, inode, name, name_len, 1, index); |
| |
| /* FIXME, put inode into FIXUP list */ |
| |
| iput(inode); |
| iput(dir); |
| return ret; |
| } |
| |
| /* |
| * take a single entry in a log directory item and replay it into |
| * the subvolume. |
| * |
| * if a conflicting item exists in the subdirectory already, |
| * the inode it points to is unlinked and put into the link count |
| * fix up tree. |
| * |
| * If a name from the log points to a file or directory that does |
| * not exist in the FS, it is skipped. fsyncs on directories |
| * do not force down inodes inside that directory, just changes to the |
| * names or unlinks in a directory. |
| */ |
| static noinline int replay_one_name(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct extent_buffer *eb, |
| struct btrfs_dir_item *di, |
| struct btrfs_key *key) |
| { |
| char *name; |
| int name_len; |
| struct btrfs_dir_item *dst_di; |
| struct btrfs_key found_key; |
| struct btrfs_key log_key; |
| struct inode *dir; |
| u8 log_type; |
| int exists; |
| int ret; |
| |
| dir = read_one_inode(root, key->objectid); |
| if (!dir) |
| return -EIO; |
| |
| name_len = btrfs_dir_name_len(eb, di); |
| name = kmalloc(name_len, GFP_NOFS); |
| if (!name) |
| return -ENOMEM; |
| |
| log_type = btrfs_dir_type(eb, di); |
| read_extent_buffer(eb, name, (unsigned long)(di + 1), |
| name_len); |
| |
| btrfs_dir_item_key_to_cpu(eb, di, &log_key); |
| exists = btrfs_lookup_inode(trans, root, path, &log_key, 0); |
| if (exists == 0) |
| exists = 1; |
| else |
| exists = 0; |
| btrfs_release_path(path); |
| |
| if (key->type == BTRFS_DIR_ITEM_KEY) { |
| dst_di = btrfs_lookup_dir_item(trans, root, path, key->objectid, |
| name, name_len, 1); |
| } else if (key->type == BTRFS_DIR_INDEX_KEY) { |
| dst_di = btrfs_lookup_dir_index_item(trans, root, path, |
| key->objectid, |
| key->offset, name, |
| name_len, 1); |
| } else { |
| BUG(); |
| } |
| if (IS_ERR_OR_NULL(dst_di)) { |
| /* we need a sequence number to insert, so we only |
| * do inserts for the BTRFS_DIR_INDEX_KEY types |
| */ |
| if (key->type != BTRFS_DIR_INDEX_KEY) |
| goto out; |
| goto insert; |
| } |
| |
| btrfs_dir_item_key_to_cpu(path->nodes[0], dst_di, &found_key); |
| /* the existing item matches the logged item */ |
| if (found_key.objectid == log_key.objectid && |
| found_key.type == log_key.type && |
| found_key.offset == log_key.offset && |
| btrfs_dir_type(path->nodes[0], dst_di) == log_type) { |
| goto out; |
| } |
| |
| /* |
| * don't drop the conflicting directory entry if the inode |
| * for the new entry doesn't exist |
| */ |
| if (!exists) |
| goto out; |
| |
| ret = drop_one_dir_item(trans, root, path, dir, dst_di); |
| BUG_ON(ret); |
| |
| if (key->type == BTRFS_DIR_INDEX_KEY) |
| goto insert; |
| out: |
| btrfs_release_path(path); |
| kfree(name); |
| iput(dir); |
| return 0; |
| |
| insert: |
| btrfs_release_path(path); |
| ret = insert_one_name(trans, root, path, key->objectid, key->offset, |
| name, name_len, log_type, &log_key); |
| |
| BUG_ON(ret && ret != -ENOENT); |
| goto out; |
| } |
| |
| /* |
| * find all the names in a directory item and reconcile them into |
| * the subvolume. Only BTRFS_DIR_ITEM_KEY types will have more than |
| * one name in a directory item, but the same code gets used for |
| * both directory index types |
| */ |
| static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct extent_buffer *eb, int slot, |
| struct btrfs_key *key) |
| { |
| int ret; |
| u32 item_size = btrfs_item_size_nr(eb, slot); |
| struct btrfs_dir_item *di; |
| int name_len; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| |
| ptr = btrfs_item_ptr_offset(eb, slot); |
| ptr_end = ptr + item_size; |
| while (ptr < ptr_end) { |
| di = (struct btrfs_dir_item *)ptr; |
| if (verify_dir_item(root, eb, di)) |
| return -EIO; |
| name_len = btrfs_dir_name_len(eb, di); |
| ret = replay_one_name(trans, root, path, eb, di, key); |
| BUG_ON(ret); |
| ptr = (unsigned long)(di + 1); |
| ptr += name_len; |
| } |
| return 0; |
| } |
| |
| /* |
| * directory replay has two parts. There are the standard directory |
| * items in the log copied from the subvolume, and range items |
| * created in the log while the subvolume was logged. |
| * |
| * The range items tell us which parts of the key space the log |
| * is authoritative for. During replay, if a key in the subvolume |
| * directory is in a logged range item, but not actually in the log |
| * that means it was deleted from the directory before the fsync |
| * and should be removed. |
| */ |
| static noinline int find_dir_range(struct btrfs_root *root, |
| struct btrfs_path *path, |
| u64 dirid, int key_type, |
| u64 *start_ret, u64 *end_ret) |
| { |
| struct btrfs_key key; |
| u64 found_end; |
| struct btrfs_dir_log_item *item; |
| int ret; |
| int nritems; |
| |
| if (*start_ret == (u64)-1) |
| return 1; |
| |
| key.objectid = dirid; |
| key.type = key_type; |
| key.offset = *start_ret; |
| |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| if (ret > 0) { |
| if (path->slots[0] == 0) |
| goto out; |
| path->slots[0]--; |
| } |
| if (ret != 0) |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| |
| if (key.type != key_type || key.objectid != dirid) { |
| ret = 1; |
| goto next; |
| } |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_dir_log_item); |
| found_end = btrfs_dir_log_end(path->nodes[0], item); |
| |
| if (*start_ret >= key.offset && *start_ret <= found_end) { |
| ret = 0; |
| *start_ret = key.offset; |
| *end_ret = found_end; |
| goto out; |
| } |
| ret = 1; |
| next: |
| /* check the next slot in the tree to see if it is a valid item */ |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| if (path->slots[0] >= nritems) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret) |
| goto out; |
| } else { |
| path->slots[0]++; |
| } |
| |
| btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); |
| |
| if (key.type != key_type || key.objectid != dirid) { |
| ret = 1; |
| goto out; |
| } |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_dir_log_item); |
| found_end = btrfs_dir_log_end(path->nodes[0], item); |
| *start_ret = key.offset; |
| *end_ret = found_end; |
| ret = 0; |
| out: |
| btrfs_release_path(path); |
| return ret; |
| } |
| |
| /* |
| * this looks for a given directory item in the log. If the directory |
| * item is not in the log, the item is removed and the inode it points |
| * to is unlinked |
| */ |
| static noinline int check_item_in_log(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| struct btrfs_path *log_path, |
| struct inode *dir, |
| struct btrfs_key *dir_key) |
| { |
| int ret; |
| struct extent_buffer *eb; |
| int slot; |
| u32 item_size; |
| struct btrfs_dir_item *di; |
| struct btrfs_dir_item *log_di; |
| int name_len; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| char *name; |
| struct inode *inode; |
| struct btrfs_key location; |
| |
| again: |
| eb = path->nodes[0]; |
| slot = path->slots[0]; |
| item_size = btrfs_item_size_nr(eb, slot); |
| ptr = btrfs_item_ptr_offset(eb, slot); |
| ptr_end = ptr + item_size; |
| while (ptr < ptr_end) { |
| di = (struct btrfs_dir_item *)ptr; |
| if (verify_dir_item(root, eb, di)) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| name_len = btrfs_dir_name_len(eb, di); |
| name = kmalloc(name_len, GFP_NOFS); |
| if (!name) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| read_extent_buffer(eb, name, (unsigned long)(di + 1), |
| name_len); |
| log_di = NULL; |
| if (log && dir_key->type == BTRFS_DIR_ITEM_KEY) { |
| log_di = btrfs_lookup_dir_item(trans, log, log_path, |
| dir_key->objectid, |
| name, name_len, 0); |
| } else if (log && dir_key->type == BTRFS_DIR_INDEX_KEY) { |
| log_di = btrfs_lookup_dir_index_item(trans, log, |
| log_path, |
| dir_key->objectid, |
| dir_key->offset, |
| name, name_len, 0); |
| } |
| if (IS_ERR_OR_NULL(log_di)) { |
| btrfs_dir_item_key_to_cpu(eb, di, &location); |
| btrfs_release_path(path); |
| btrfs_release_path(log_path); |
| inode = read_one_inode(root, location.objectid); |
| if (!inode) { |
| kfree(name); |
| return -EIO; |
| } |
| |
| ret = link_to_fixup_dir(trans, root, |
| path, location.objectid); |
| BUG_ON(ret); |
| btrfs_inc_nlink(inode); |
| ret = btrfs_unlink_inode(trans, root, dir, inode, |
| name, name_len); |
| BUG_ON(ret); |
| kfree(name); |
| iput(inode); |
| |
| /* there might still be more names under this key |
| * check and repeat if required |
| */ |
| ret = btrfs_search_slot(NULL, root, dir_key, path, |
| 0, 0); |
| if (ret == 0) |
| goto again; |
| ret = 0; |
| goto out; |
| } |
| btrfs_release_path(log_path); |
| kfree(name); |
| |
| ptr = (unsigned long)(di + 1); |
| ptr += name_len; |
| } |
| ret = 0; |
| out: |
| btrfs_release_path(path); |
| btrfs_release_path(log_path); |
| return ret; |
| } |
| |
| /* |
| * deletion replay happens before we copy any new directory items |
| * out of the log or out of backreferences from inodes. It |
| * scans the log to find ranges of keys that log is authoritative for, |
| * and then scans the directory to find items in those ranges that are |
| * not present in the log. |
| * |
| * Anything we don't find in the log is unlinked and removed from the |
| * directory. |
| */ |
| static noinline int replay_dir_deletes(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| u64 dirid, int del_all) |
| { |
| u64 range_start; |
| u64 range_end; |
| int key_type = BTRFS_DIR_LOG_ITEM_KEY; |
| int ret = 0; |
| struct btrfs_key dir_key; |
| struct btrfs_key found_key; |
| struct btrfs_path *log_path; |
| struct inode *dir; |
| |
| dir_key.objectid = dirid; |
| dir_key.type = BTRFS_DIR_ITEM_KEY; |
| log_path = btrfs_alloc_path(); |
| if (!log_path) |
| return -ENOMEM; |
| |
| dir = read_one_inode(root, dirid); |
| /* it isn't an error if the inode isn't there, that can happen |
| * because we replay the deletes before we copy in the inode item |
| * from the log |
| */ |
| if (!dir) { |
| btrfs_free_path(log_path); |
| return 0; |
| } |
| again: |
| range_start = 0; |
| range_end = 0; |
| while (1) { |
| if (del_all) |
| range_end = (u64)-1; |
| else { |
| ret = find_dir_range(log, path, dirid, key_type, |
| &range_start, &range_end); |
| if (ret != 0) |
| break; |
| } |
| |
| dir_key.offset = range_start; |
| while (1) { |
| int nritems; |
| ret = btrfs_search_slot(NULL, root, &dir_key, path, |
| 0, 0); |
| if (ret < 0) |
| goto out; |
| |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| if (path->slots[0] >= nritems) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret) |
| break; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| path->slots[0]); |
| if (found_key.objectid != dirid || |
| found_key.type != dir_key.type) |
| goto next_type; |
| |
| if (found_key.offset > range_end) |
| break; |
| |
| ret = check_item_in_log(trans, root, log, path, |
| log_path, dir, |
| &found_key); |
| BUG_ON(ret); |
| if (found_key.offset == (u64)-1) |
| break; |
| dir_key.offset = found_key.offset + 1; |
| } |
| btrfs_release_path(path); |
| if (range_end == (u64)-1) |
| break; |
| range_start = range_end + 1; |
| } |
| |
| next_type: |
| ret = 0; |
| if (key_type == BTRFS_DIR_LOG_ITEM_KEY) { |
| key_type = BTRFS_DIR_LOG_INDEX_KEY; |
| dir_key.type = BTRFS_DIR_INDEX_KEY; |
| btrfs_release_path(path); |
| goto again; |
| } |
| out: |
| btrfs_release_path(path); |
| btrfs_free_path(log_path); |
| iput(dir); |
| return ret; |
| } |
| |
| /* |
| * the process_func used to replay items from the log tree. This |
| * gets called in two different stages. The first stage just looks |
| * for inodes and makes sure they are all copied into the subvolume. |
| * |
| * The second stage copies all the other item types from the log into |
| * the subvolume. The two stage approach is slower, but gets rid of |
| * lots of complexity around inodes referencing other inodes that exist |
| * only in the log (references come from either directory items or inode |
| * back refs). |
| */ |
| static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb, |
| struct walk_control *wc, u64 gen) |
| { |
| int nritems; |
| struct btrfs_path *path; |
| struct btrfs_root *root = wc->replay_dest; |
| struct btrfs_key key; |
| int level; |
| int i; |
| int ret; |
| |
| btrfs_read_buffer(eb, gen); |
| |
| level = btrfs_header_level(eb); |
| |
| if (level != 0) |
| return 0; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| nritems = btrfs_header_nritems(eb); |
| for (i = 0; i < nritems; i++) { |
| btrfs_item_key_to_cpu(eb, &key, i); |
| |
| /* inode keys are done during the first stage */ |
| if (key.type == BTRFS_INODE_ITEM_KEY && |
| wc->stage == LOG_WALK_REPLAY_INODES) { |
| struct btrfs_inode_item *inode_item; |
| u32 mode; |
| |
| inode_item = btrfs_item_ptr(eb, i, |
| struct btrfs_inode_item); |
| mode = btrfs_inode_mode(eb, inode_item); |
| if (S_ISDIR(mode)) { |
| ret = replay_dir_deletes(wc->trans, |
| root, log, path, key.objectid, 0); |
| BUG_ON(ret); |
| } |
| ret = overwrite_item(wc->trans, root, path, |
| eb, i, &key); |
| BUG_ON(ret); |
| |
| /* for regular files, make sure corresponding |
| * orhpan item exist. extents past the new EOF |
| * will be truncated later by orphan cleanup. |
| */ |
| if (S_ISREG(mode)) { |
| ret = insert_orphan_item(wc->trans, root, |
| key.objectid); |
| BUG_ON(ret); |
| } |
| |
| ret = link_to_fixup_dir(wc->trans, root, |
| path, key.objectid); |
| BUG_ON(ret); |
| } |
| if (wc->stage < LOG_WALK_REPLAY_ALL) |
| continue; |
| |
| /* these keys are simply copied */ |
| if (key.type == BTRFS_XATTR_ITEM_KEY) { |
| ret = overwrite_item(wc->trans, root, path, |
| eb, i, &key); |
| BUG_ON(ret); |
| } else if (key.type == BTRFS_INODE_REF_KEY) { |
| ret = add_inode_ref(wc->trans, root, log, path, |
| eb, i, &key); |
| BUG_ON(ret && ret != -ENOENT); |
| } else if (key.type == BTRFS_EXTENT_DATA_KEY) { |
| ret = replay_one_extent(wc->trans, root, path, |
| eb, i, &key); |
| BUG_ON(ret); |
| } else if (key.type == BTRFS_DIR_ITEM_KEY || |
| key.type == BTRFS_DIR_INDEX_KEY) { |
| ret = replay_one_dir_item(wc->trans, root, path, |
| eb, i, &key); |
| BUG_ON(ret); |
| } |
| } |
| btrfs_free_path(path); |
| return 0; |
| } |
| |
| static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, int *level, |
| struct walk_control *wc) |
| { |
| u64 root_owner; |
| u64 bytenr; |
| u64 ptr_gen; |
| struct extent_buffer *next; |
| struct extent_buffer *cur; |
| struct extent_buffer *parent; |
| u32 blocksize; |
| int ret = 0; |
| |
| WARN_ON(*level < 0); |
| WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| |
| while (*level > 0) { |
| WARN_ON(*level < 0); |
| WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| cur = path->nodes[*level]; |
| |
| if (btrfs_header_level(cur) != *level) |
| WARN_ON(1); |
| |
| if (path->slots[*level] >= |
| btrfs_header_nritems(cur)) |
| break; |
| |
| bytenr = btrfs_node_blockptr(cur, path->slots[*level]); |
| ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); |
| blocksize = btrfs_level_size(root, *level - 1); |
| |
| parent = path->nodes[*level]; |
| root_owner = btrfs_header_owner(parent); |
| |
| next = btrfs_find_create_tree_block(root, bytenr, blocksize); |
| if (!next) |
| return -ENOMEM; |
| |
| if (*level == 1) { |
| ret = wc->process_func(root, next, wc, ptr_gen); |
| if (ret) |
| return ret; |
| |
| path->slots[*level]++; |
| if (wc->free) { |
| btrfs_read_buffer(next, ptr_gen); |
| |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(trans, root, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| |
| WARN_ON(root_owner != |
| BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_reserved_extent(root, |
| bytenr, blocksize); |
| BUG_ON(ret); |
| } |
| free_extent_buffer(next); |
| continue; |
| } |
| btrfs_read_buffer(next, ptr_gen); |
| |
| WARN_ON(*level <= 0); |
| if (path->nodes[*level-1]) |
| free_extent_buffer(path->nodes[*level-1]); |
| path->nodes[*level-1] = next; |
| *level = btrfs_header_level(next); |
| path->slots[*level] = 0; |
| cond_resched(); |
| } |
| WARN_ON(*level < 0); |
| WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| |
| path->slots[*level] = btrfs_header_nritems(path->nodes[*level]); |
| |
| cond_resched(); |
| return 0; |
| } |
| |
| static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, int *level, |
| struct walk_control *wc) |
| { |
| u64 root_owner; |
| int i; |
| int slot; |
| int ret; |
| |
| for (i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { |
| slot = path->slots[i]; |
| if (slot + 1 < btrfs_header_nritems(path->nodes[i])) { |
| path->slots[i]++; |
| *level = i; |
| WARN_ON(*level == 0); |
| return 0; |
| } else { |
| struct extent_buffer *parent; |
| if (path->nodes[*level] == root->node) |
| parent = path->nodes[*level]; |
| else |
| parent = path->nodes[*level + 1]; |
| |
| root_owner = btrfs_header_owner(parent); |
| ret = wc->process_func(root, path->nodes[*level], wc, |
| btrfs_header_generation(path->nodes[*level])); |
| if (ret) |
| return ret; |
| |
| if (wc->free) { |
| struct extent_buffer *next; |
| |
| next = path->nodes[*level]; |
| |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(trans, root, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| |
| WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_reserved_extent(root, |
| path->nodes[*level]->start, |
| path->nodes[*level]->len); |
| BUG_ON(ret); |
| } |
| free_extent_buffer(path->nodes[*level]); |
| path->nodes[*level] = NULL; |
| *level = i + 1; |
| } |
| } |
| return 1; |
| } |
| |
| /* |
| * drop the reference count on the tree rooted at 'snap'. This traverses |
| * the tree freeing any blocks that have a ref count of zero after being |
| * decremented. |
| */ |
| static int walk_log_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log, struct walk_control *wc) |
| { |
| int ret = 0; |
| int wret; |
| int level; |
| struct btrfs_path *path; |
| int i; |
| int orig_level; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| level = btrfs_header_level(log->node); |
| orig_level = level; |
| path->nodes[level] = log->node; |
| extent_buffer_get(log->node); |
| path->slots[level] = 0; |
| |
| while (1) { |
| wret = walk_down_log_tree(trans, log, path, &level, wc); |
| if (wret > 0) |
| break; |
| if (wret < 0) |
| ret = wret; |
| |
| wret = walk_up_log_tree(trans, log, path, &level, wc); |
| if (wret > 0) |
| break; |
| if (wret < 0) |
| ret = wret; |
| } |
| |
| /* was the root node processed? if not, catch it here */ |
| if (path->nodes[orig_level]) { |
| wc->process_func(log, path->nodes[orig_level], wc, |
| btrfs_header_generation(path->nodes[orig_level])); |
| if (wc->free) { |
| struct extent_buffer *next; |
| |
| next = path->nodes[orig_level]; |
| |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(trans, log, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| |
| WARN_ON(log->root_key.objectid != |
| BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_reserved_extent(log, next->start, |
| next->len); |
| BUG_ON(ret); |
| } |
| } |
| |
| for (i = 0; i <= orig_level; i++) { |
| if (path->nodes[i]) { |
| free_extent_buffer(path->nodes[i]); |
| path->nodes[i] = NULL; |
| } |
| } |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * helper function to update the item for a given subvolumes log root |
| * in the tree of log roots |
| */ |
| static int update_log_root(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log) |
| { |
| int ret; |
| |
| if (log->log_transid == 1) { |
| /* insert root item on the first sync */ |
| ret = btrfs_insert_root(trans, log->fs_info->log_root_tree, |
| &log->root_key, &log->root_item); |
| } else { |
| ret = btrfs_update_root(trans, log->fs_info->log_root_tree, |
| &log->root_key, &log->root_item); |
| } |
| return ret; |
| } |
| |
| static int wait_log_commit(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, unsigned long transid) |
| { |
| DEFINE_WAIT(wait); |
| int index = transid % 2; |
| |
| /* |
| * we only allow two pending log transactions at a time, |
| * so we know that if ours is more than 2 older than the |
| * current transaction, we're done |
| */ |
| do { |
| prepare_to_wait(&root->log_commit_wait[index], |
| &wait, TASK_UNINTERRUPTIBLE); |
| mutex_unlock(&root->log_mutex); |
| |
| if (root->fs_info->last_trans_log_full_commit != |
| trans->transid && root->log_transid < transid + 2 && |
| atomic_read(&root->log_commit[index])) |
| schedule(); |
| |
| finish_wait(&root->log_commit_wait[index], &wait); |
| mutex_lock(&root->log_mutex); |
| } while (root->log_transid < transid + 2 && |
| atomic_read(&root->log_commit[index])); |
| return 0; |
| } |
| |
| static int wait_for_writer(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root) |
| { |
| DEFINE_WAIT(wait); |
| while (atomic_read(&root->log_writers)) { |
| prepare_to_wait(&root->log_writer_wait, |
| &wait, TASK_UNINTERRUPTIBLE); |
| mutex_unlock(&root->log_mutex); |
| if (root->fs_info->last_trans_log_full_commit != |
| trans->transid && atomic_read(&root->log_writers)) |
| schedule(); |
| mutex_lock(&root->log_mutex); |
| finish_wait(&root->log_writer_wait, &wait); |
| } |
| return 0; |
| } |
| |
| /* |
| * btrfs_sync_log does sends a given tree log down to the disk and |
| * updates the super blocks to record it. When this call is done, |
| * you know that any inodes previously logged are safely on disk only |
| * if it returns 0. |
| * |
| * Any other return value means you need to call btrfs_commit_transaction. |
| * Some of the edge cases for fsyncing directories that have had unlinks |
| * or renames done in the past mean that sometimes the only safe |
| * fsync is to commit the whole FS. When btrfs_sync_log returns -EAGAIN, |
| * that has happened. |
| */ |
| int btrfs_sync_log(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root) |
| { |
| int index1; |
| int index2; |
| int mark; |
| int ret; |
| struct btrfs_root *log = root->log_root; |
| struct btrfs_root *log_root_tree = root->fs_info->log_root_tree; |
| unsigned long log_transid = 0; |
| |
| mutex_lock(&root->log_mutex); |
| index1 = root->log_transid % 2; |
| if (atomic_read(&root->log_commit[index1])) { |
| wait_log_commit(trans, root, root->log_transid); |
| mutex_unlock(&root->log_mutex); |
| return 0; |
| } |
| atomic_set(&root->log_commit[index1], 1); |
| |
| /* wait for previous tree log sync to complete */ |
| if (atomic_read(&root->log_commit[(index1 + 1) % 2])) |
| wait_log_commit(trans, root, root->log_transid - 1); |
| while (1) { |
| unsigned long batch = root->log_batch; |
| /* when we're on an ssd, just kick the log commit out */ |
| if (!btrfs_test_opt(root, SSD) && root->log_multiple_pids) { |
| mutex_unlock(&root->log_mutex); |
| schedule_timeout_uninterruptible(1); |
| mutex_lock(&root->log_mutex); |
| } |
| wait_for_writer(trans, root); |
| if (batch == root->log_batch) |
| break; |
| } |
| |
| /* bail out if we need to do a full commit */ |
| if (root->fs_info->last_trans_log_full_commit == trans->transid) { |
| ret = -EAGAIN; |
| mutex_unlock(&root->log_mutex); |
| goto out; |
| } |
| |
| log_transid = root->log_transid; |
| if (log_transid % 2 == 0) |
| mark = EXTENT_DIRTY; |
| else |
| mark = EXTENT_NEW; |
| |
| /* we start IO on all the marked extents here, but we don't actually |
| * wait for them until later. |
| */ |
| ret = btrfs_write_marked_extents(log, &log->dirty_log_pages, mark); |
| BUG_ON(ret); |
| |
| btrfs_set_root_node(&log->root_item, log->node); |
| |
| root->log_batch = 0; |
| root->log_transid++; |
| log->log_transid = root->log_transid; |
| root->log_start_pid = 0; |
| smp_mb(); |
| /* |
| * IO has been started, blocks of the log tree have WRITTEN flag set |
| * in their headers. new modifications of the log will be written to |
| * new positions. so it's safe to allow log writers to go in. |
| */ |
| mutex_unlock(&root->log_mutex); |
| |
| mutex_lock(&log_root_tree->log_mutex); |
| log_root_tree->log_batch++; |
| atomic_inc(&log_root_tree->log_writers); |
| mutex_unlock(&log_root_tree->log_mutex); |
| |
| ret = update_log_root(trans, log); |
| |
| mutex_lock(&log_root_tree->log_mutex); |
| if (atomic_dec_and_test(&log_root_tree->log_writers)) { |
| smp_mb(); |
| if (waitqueue_active(&log_root_tree->log_writer_wait)) |
| wake_up(&log_root_tree->log_writer_wait); |
| } |
| |
| if (ret) { |
| BUG_ON(ret != -ENOSPC); |
| root->fs_info->last_trans_log_full_commit = trans->transid; |
| btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark); |
| mutex_unlock(&log_root_tree->log_mutex); |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| index2 = log_root_tree->log_transid % 2; |
| if (atomic_read(&log_root_tree->log_commit[index2])) { |
| btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark); |
| wait_log_commit(trans, log_root_tree, |
| log_root_tree->log_transid); |
| mutex_unlock(&log_root_tree->log_mutex); |
| ret = 0; |
| goto out; |
| } |
| atomic_set(&log_root_tree->log_commit[index2], 1); |
| |
| if (atomic_read(&log_root_tree->log_commit[(index2 + 1) % 2])) { |
| wait_log_commit(trans, log_root_tree, |
| log_root_tree->log_transid - 1); |
| } |
| |
| wait_for_writer(trans, log_root_tree); |
| |
| /* |
| * now that we've moved on to the tree of log tree roots, |
| * check the full commit flag again |
| */ |
| if (root->fs_info->last_trans_log_full_commit == trans->transid) { |
| btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark); |
| mutex_unlock(&log_root_tree->log_mutex); |
| ret = -EAGAIN; |
| goto out_wake_log_root; |
| } |
| |
| ret = btrfs_write_and_wait_marked_extents(log_root_tree, |
| &log_root_tree->dirty_log_pages, |
| EXTENT_DIRTY | EXTENT_NEW); |
| BUG_ON(ret); |
| btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark); |
| |
| btrfs_set_super_log_root(&root->fs_info->super_for_commit, |
| log_root_tree->node->start); |
| btrfs_set_super_log_root_level(&root->fs_info->super_for_commit, |
| btrfs_header_level(log_root_tree->node)); |
| |
| log_root_tree->log_batch = 0; |
| log_root_tree->log_transid++; |
| smp_mb(); |
| |
| mutex_unlock(&log_root_tree->log_mutex); |
| |
| /* |
| * nobody else is going to jump in and write the the ctree |
| * super here because the log_commit atomic below is protecting |
| * us. We must be called with a transaction handle pinning |
| * the running transaction open, so a full commit can't hop |
| * in and cause problems either. |
| */ |
| btrfs_scrub_pause_super(root); |
| write_ctree_super(trans, root->fs_info->tree_root, 1); |
| btrfs_scrub_continue_super(root); |
| ret = 0; |
| |
| mutex_lock(&root->log_mutex); |
| if (root->last_log_commit < log_transid) |
| root->last_log_commit = log_transid; |
| mutex_unlock(&root->log_mutex); |
| |
| out_wake_log_root: |
| atomic_set(&log_root_tree->log_commit[index2], 0); |
| smp_mb(); |
| if (waitqueue_active(&log_root_tree->log_commit_wait[index2])) |
| wake_up(&log_root_tree->log_commit_wait[index2]); |
| out: |
| atomic_set(&root->log_commit[index1], 0); |
| smp_mb(); |
| if (waitqueue_active(&root->log_commit_wait[index1])) |
| wake_up(&root->log_commit_wait[index1]); |
| return ret; |
| } |
| |
| static void free_log_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log) |
| { |
| int ret; |
| u64 start; |
| u64 end; |
| struct walk_control wc = { |
| .free = 1, |
| .process_func = process_one_buffer |
| }; |
| |
| ret = walk_log_tree(trans, log, &wc); |
| BUG_ON(ret); |
| |
| while (1) { |
| ret = find_first_extent_bit(&log->dirty_log_pages, |
| 0, &start, &end, EXTENT_DIRTY | EXTENT_NEW); |
| if (ret) |
| break; |
| |
| clear_extent_bits(&log->dirty_log_pages, start, end, |
| EXTENT_DIRTY | EXTENT_NEW, GFP_NOFS); |
| } |
| |
| free_extent_buffer(log->node); |
| kfree(log); |
| } |
| |
| /* |
| * free all the extents used by the tree log. This should be called |
| * at commit time of the full transaction |
| */ |
| int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root) |
| { |
| if (root->log_root) { |
| free_log_tree(trans, root->log_root); |
| root->log_root = NULL; |
| } |
| return 0; |
| } |
| |
| int btrfs_free_log_root_tree(struct btrfs_trans_handle *trans, |
| struct btrfs_fs_info *fs_info) |
| { |
| if (fs_info->log_root_tree) { |
| free_log_tree(trans, fs_info->log_root_tree); |
| fs_info->log_root_tree = NULL; |
| } |
| return 0; |
| } |
| |
| /* |
| * If both a file and directory are logged, and unlinks or renames are |
| * mixed in, we have a few interesting corners: |
| * |
| * create file X in dir Y |
| * link file X to X.link in dir Y |
| * fsync file X |
| * unlink file X but leave X.link |
| * fsync dir Y |
| * |
| * After a crash we would expect only X.link to exist. But file X |
| * didn't get fsync'd again so the log has back refs for X and X.link. |
| * |
| * We solve this by removing directory entries and inode backrefs from the |
| * log when a file that was logged in the current transaction is |
| * unlinked. Any later fsync will include the updated log entries, and |
| * we'll be able to reconstruct the proper directory items from backrefs. |
| * |
| * This optimizations allows us to avoid relogging the entire inode |
| * or the entire directory. |
| */ |
| int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| const char *name, int name_len, |
| struct inode *dir, u64 index) |
| { |
| struct btrfs_root *log; |
| struct btrfs_dir_item *di; |
| struct btrfs_path *path; |
| int ret; |
| int err = 0; |
| int bytes_del = 0; |
| u64 dir_ino = btrfs_ino(dir); |
| |
| if (BTRFS_I(dir)->logged_trans < trans->transid) |
| return 0; |
| |
| ret = join_running_log_trans(root); |
| if (ret) |
| return 0; |
| |
| mutex_lock(&BTRFS_I(dir)->log_mutex); |
| |
| log = root->log_root; |
| path = btrfs_alloc_path(); |
| if (!path) { |
| err = -ENOMEM; |
| goto out_unlock; |
| } |
| |
| di = btrfs_lookup_dir_item(trans, log, path, dir_ino, |
| name, name_len, -1); |
| if (IS_ERR(di)) { |
| err = PTR_ERR(di); |
| goto fail; |
| } |
| if (di) { |
| ret = btrfs_delete_one_dir_name(trans, log, path, di); |
| bytes_del += name_len; |
| BUG_ON(ret); |
| } |
| btrfs_release_path(path); |
| di = btrfs_lookup_dir_index_item(trans, log, path, dir_ino, |
| index, name, name_len, -1); |
| if (IS_ERR(di)) { |
| err = PTR_ERR(di); |
| goto fail; |
| } |
| if (di) { |
| ret = btrfs_delete_one_dir_name(trans, log, path, di); |
| bytes_del += name_len; |
| BUG_ON(ret); |
| } |
| |
| /* update the directory size in the log to reflect the names |
| * we have removed |
| */ |
| if (bytes_del) { |
| struct btrfs_key key; |
| |
| key.objectid = dir_ino; |
| key.offset = 0; |
| key.type = BTRFS_INODE_ITEM_KEY; |
| btrfs_release_path(path); |
| |
| ret = btrfs_search_slot(trans, log, &key, path, 0, 1); |
| if (ret < 0) { |
| err = ret; |
| goto fail; |
| } |
| if (ret == 0) { |
| struct btrfs_inode_item *item; |
| u64 i_size; |
| |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_inode_item); |
| i_size = btrfs_inode_size(path->nodes[0], item); |
| if (i_size > bytes_del) |
| i_size -= bytes_del; |
| else |
| i_size = 0; |
| btrfs_set_inode_size(path->nodes[0], item, i_size); |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| } else |
| ret = 0; |
| btrfs_release_path(path); |
| } |
| fail: |
| btrfs_free_path(path); |
| out_unlock: |
| mutex_unlock(&BTRFS_I(dir)->log_mutex); |
| if (ret == -ENOSPC) { |
| root->fs_info->last_trans_log_full_commit = trans->transid; |
| ret = 0; |
| } |
| btrfs_end_log_trans(root); |
| |
| return err; |
| } |
| |
| /* see comments for btrfs_del_dir_entries_in_log */ |
| int btrfs_del_inode_ref_in_log(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| const char *name, int name_len, |
| struct inode *inode, u64 dirid) |
| { |
| struct btrfs_root *log; |
| u64 index; |
| int ret; |
| |
| if (BTRFS_I(inode)->logged_trans < trans->transid) |
| return 0; |
| |
| ret = join_running_log_trans(root); |
| if (ret) |
| return 0; |
| log = root->log_root; |
| mutex_lock(&BTRFS_I(inode)->log_mutex); |
| |
| ret = btrfs_del_inode_ref(trans, log, name, name_len, btrfs_ino(inode), |
| dirid, &index); |
| mutex_unlock(&BTRFS_I(inode)->log_mutex); |
| if (ret == -ENOSPC) { |
| root->fs_info->last_trans_log_full_commit = trans->transid; |
| ret = 0; |
| } |
| btrfs_end_log_trans(root); |
| |
| return ret; |
| } |
| |
| /* |
| * creates a range item in the log for 'dirid'. first_offset and |
| * last_offset tell us which parts of the key space the log should |
| * be considered authoritative for. |
| */ |
| static noinline int insert_dir_log_key(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| int key_type, u64 dirid, |
| u64 first_offset, u64 last_offset) |
| { |
| int ret; |
| struct btrfs_key key; |
| struct btrfs_dir_log_item *item; |
| |
| key.objectid = dirid; |
| key.offset = first_offset; |
| if (key_type == BTRFS_DIR_ITEM_KEY) |
| key.type = BTRFS_DIR_LOG_ITEM_KEY; |
| else |
| key.type = BTRFS_DIR_LOG_INDEX_KEY; |
| ret = btrfs_insert_empty_item(trans, log, path, &key, sizeof(*item)); |
| if (ret) |
| return ret; |
| |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_dir_log_item); |
| btrfs_set_dir_log_end(path->nodes[0], item, last_offset); |
| btrfs_mark_buffer_dirty(path->nodes[0]); |
| btrfs_release_path(path); |
| return 0; |
| } |
| |
| /* |
| * log all the items included in the current transaction for a given |
| * directory. This also creates the range items in the log tree required |
| * to replay anything deleted before the fsync |
| */ |
| static noinline int log_dir_items(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| struct btrfs_path *path, |
| struct btrfs_path *dst_path, int key_type, |
| u64 min_offset, u64 *last_offset_ret) |
| { |
| struct btrfs_key min_key; |
| struct btrfs_key max_key; |
| struct btrfs_root *log = root->log_root; |
| struct extent_buffer *src; |
| int err = 0; |
| int ret; |
| int i; |
| int nritems; |
| u64 first_offset = min_offset; |
| u64 last_offset = (u64)-1; |
| u64 ino = btrfs_ino(inode); |
| |
| log = root->log_root; |
| max_key.objectid = ino; |
| max_key.offset = (u64)-1; |
| max_key.type = key_type; |
| |
| min_key.objectid = ino; |
| min_key.type = key_type; |
| min_key.offset = min_offset; |
| |
| path->keep_locks = 1; |
| |
| ret = btrfs_search_forward(root, &min_key, &max_key, |
| path, 0, trans->transid); |
| |
| /* |
| * we didn't find anything from this transaction, see if there |
| * is anything at all |
| */ |
| if (ret != 0 || min_key.objectid != ino || min_key.type != key_type) { |
| min_key.objectid = ino; |
| min_key.type = key_type; |
| min_key.offset = (u64)-1; |
| btrfs_release_path(path); |
| ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0); |
| if (ret < 0) { |
| btrfs_release_path(path); |
| return ret; |
| } |
| ret = btrfs_previous_item(root, path, ino, key_type); |
| |
| /* if ret == 0 there are items for this type, |
| * create a range to tell us the last key of this type. |
| * otherwise, there are no items in this directory after |
| * *min_offset, and we create a range to indicate that. |
| */ |
| if (ret == 0) { |
| struct btrfs_key tmp; |
| btrfs_item_key_to_cpu(path->nodes[0], &tmp, |
| path->slots[0]); |
| if (key_type == tmp.type) |
| first_offset = max(min_offset, tmp.offset) + 1; |
| } |
| goto done; |
| } |
| |
| /* go backward to find any previous key */ |
| ret = btrfs_previous_item(root, path, ino, key_type); |
| if (ret == 0) { |
| struct btrfs_key tmp; |
| btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]); |
| if (key_type == tmp.type) { |
| first_offset = tmp.offset; |
| ret = overwrite_item(trans, log, dst_path, |
| path->nodes[0], path->slots[0], |
| &tmp); |
| if (ret) { |
| err = ret; |
| goto done; |
| } |
| } |
| } |
| btrfs_release_path(path); |
| |
| /* find the first key from this transaction again */ |
| ret = btrfs_search_slot(NULL, root, &min_key, path, 0, 0); |
| if (ret != 0) { |
| WARN_ON(1); |
| goto done; |
| } |
| |
| /* |
| * we have a block from this transaction, log every item in it |
| * from our directory |
| */ |
| while (1) { |
| struct btrfs_key tmp; |
| src = path->nodes[0]; |
| nritems = btrfs_header_nritems(src); |
| for (i = path->slots[0]; i < nritems; i++) { |
| btrfs_item_key_to_cpu(src, &min_key, i); |
| |
| if (min_key.objectid != ino || min_key.type != key_type) |
| goto done; |
| ret = overwrite_item(trans, log, dst_path, src, i, |
| &min_key); |
| if (ret) { |
| err = ret; |
| goto done; |
| } |
| } |
| path->slots[0] = nritems; |
| |
| /* |
| * look ahead to the next item and see if it is also |
| * from this directory and from this transaction |
| */ |
| ret = btrfs_next_leaf(root, path); |
| if (ret == 1) { |
| last_offset = (u64)-1; |
| goto done; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &tmp, path->slots[0]); |
| if (tmp.objectid != ino || tmp.type != key_type) { |
| last_offset = (u64)-1; |
| goto done; |
| } |
| if (btrfs_header_generation(path->nodes[0]) != trans->transid) { |
| ret = overwrite_item(trans, log, dst_path, |
| path->nodes[0], path->slots[0], |
| &tmp); |
| if (ret) |
| err = ret; |
| else |
| last_offset = tmp.offset; |
| goto done; |
| } |
| } |
| done: |
| btrfs_release_path(path); |
| btrfs_release_path(dst_path); |
| |
| if (err == 0) { |
| *last_offset_ret = last_offset; |
| /* |
| * insert the log range keys to indicate where the log |
| * is valid |
| */ |
| ret = insert_dir_log_key(trans, log, path, key_type, |
| ino, first_offset, last_offset); |
| if (ret) |
| err = ret; |
| } |
| return err; |
| } |
| |
| /* |
| * logging directories is very similar to logging inodes, We find all the items |
| * from the current transaction and write them to the log. |
| * |
| * The recovery code scans the directory in the subvolume, and if it finds a |
| * key in the range logged that is not present in the log tree, then it means |
| * that dir entry was unlinked during the transaction. |
| * |
| * In order for that scan to work, we must include one key smaller than |
| * the smallest logged by this transaction and one key larger than the largest |
| * key logged by this transaction. |
| */ |
| static noinline int log_directory_changes(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| struct btrfs_path *path, |
| struct btrfs_path *dst_path) |
| { |
| u64 min_key; |
| u64 max_key; |
| int ret; |
| int key_type = BTRFS_DIR_ITEM_KEY; |
| |
| again: |
| min_key = 0; |
| max_key = 0; |
| while (1) { |
| ret = log_dir_items(trans, root, inode, path, |
| dst_path, key_type, min_key, |
| &max_key); |
| if (ret) |
| return ret; |
| if (max_key == (u64)-1) |
| break; |
| min_key = max_key + 1; |
| } |
| |
| if (key_type == BTRFS_DIR_ITEM_KEY) { |
| key_type = BTRFS_DIR_INDEX_KEY; |
| goto again; |
| } |
| return 0; |
| } |
| |
| /* |
| * a helper function to drop items from the log before we relog an |
| * inode. max_key_type indicates the highest item type to remove. |
| * This cannot be run for file data extents because it does not |
| * free the extents they point to. |
| */ |
| static int drop_objectid_items(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| u64 objectid, int max_key_type) |
| { |
| int ret; |
| struct btrfs_key key; |
| struct btrfs_key found_key; |
| |
| key.objectid = objectid; |
| key.type = max_key_type; |
| key.offset = (u64)-1; |
| |
| while (1) { |
| ret = btrfs_search_slot(trans, log, &key, path, -1, 1); |
| BUG_ON(ret == 0); |
| if (ret < 0) |
| break; |
| |
| if (path->slots[0] == 0) |
| break; |
| |
| path->slots[0]--; |
| btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| path->slots[0]); |
| |
| if (found_key.objectid != objectid) |
| break; |
| |
| ret = btrfs_del_item(trans, log, path); |
| if (ret) |
| break; |
| btrfs_release_path(path); |
| } |
| btrfs_release_path(path); |
| return ret; |
| } |
| |
| static noinline int copy_items(struct btrfs_trans_handle *trans, |
| struct btrfs_root *log, |
| struct btrfs_path *dst_path, |
| struct extent_buffer *src, |
| int start_slot, int nr, int inode_only) |
| { |
| unsigned long src_offset; |
| unsigned long dst_offset; |
| struct btrfs_file_extent_item *extent; |
| struct btrfs_inode_item *inode_item; |
| int ret; |
| struct btrfs_key *ins_keys; |
| u32 *ins_sizes; |
| char *ins_data; |
| int i; |
| struct list_head ordered_sums; |
| |
| INIT_LIST_HEAD(&ordered_sums); |
| |
| ins_data = kmalloc(nr * sizeof(struct btrfs_key) + |
| nr * sizeof(u32), GFP_NOFS); |
| if (!ins_data) |
| return -ENOMEM; |
| |
| ins_sizes = (u32 *)ins_data; |
| ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32)); |
| |
| for (i = 0; i < nr; i++) { |
| ins_sizes[i] = btrfs_item_size_nr(src, i + start_slot); |
| btrfs_item_key_to_cpu(src, ins_keys + i, i + start_slot); |
| } |
| ret = btrfs_insert_empty_items(trans, log, dst_path, |
| ins_keys, ins_sizes, nr); |
| if (ret) { |
| kfree(ins_data); |
| return ret; |
| } |
| |
| for (i = 0; i < nr; i++, dst_path->slots[0]++) { |
| dst_offset = btrfs_item_ptr_offset(dst_path->nodes[0], |
| dst_path->slots[0]); |
| |
| src_offset = btrfs_item_ptr_offset(src, start_slot + i); |
| |
| copy_extent_buffer(dst_path->nodes[0], src, dst_offset, |
| src_offset, ins_sizes[i]); |
| |
| if (inode_only == LOG_INODE_EXISTS && |
| ins_keys[i].type == BTRFS_INODE_ITEM_KEY) { |
| inode_item = btrfs_item_ptr(dst_path->nodes[0], |
| dst_path->slots[0], |
| struct btrfs_inode_item); |
| btrfs_set_inode_size(dst_path->nodes[0], inode_item, 0); |
| |
| /* set the generation to zero so the recover code |
| * can tell the difference between an logging |
| * just to say 'this inode exists' and a logging |
| * to say 'update this inode with these values' |
| */ |
| btrfs_set_inode_generation(dst_path->nodes[0], |
| inode_item, 0); |
| } |
| /* take a reference on file data extents so that truncates |
| * or deletes of this inode don't have to relog the inode |
| * again |
| */ |
| if (btrfs_key_type(ins_keys + i) == BTRFS_EXTENT_DATA_KEY) { |
| int found_type; |
| extent = btrfs_item_ptr(src, start_slot + i, |
| struct btrfs_file_extent_item); |
| |
| if (btrfs_file_extent_generation(src, extent) < trans->transid) |
| continue; |
| |
| found_type = btrfs_file_extent_type(src, extent); |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| u64 ds, dl, cs, cl; |
| ds = btrfs_file_extent_disk_bytenr(src, |
| extent); |
| /* ds == 0 is a hole */ |
| if (ds == 0) |
| continue; |
| |
| dl = btrfs_file_extent_disk_num_bytes(src, |
| extent); |
| cs = btrfs_file_extent_offset(src, extent); |
| cl = btrfs_file_extent_num_bytes(src, |
| extent); |
| if (btrfs_file_extent_compression(src, |
| extent)) { |
| cs = 0; |
| cl = dl; |
| } |
| |
| ret = btrfs_lookup_csums_range( |
| log->fs_info->csum_root, |
| ds + cs, ds + cs + cl - 1, |
| &ordered_sums, 0); |
| BUG_ON(ret); |
| } |
| } |
| } |
| |
| btrfs_mark_buffer_dirty(dst_path->nodes[0]); |
| btrfs_release_path(dst_path); |
| kfree(ins_data); |
| |
| /* |
| * we have to do this after the loop above to avoid changing the |
| * log tree while trying to change the log tree. |
| */ |
| ret = 0; |
| while (!list_empty(&ordered_sums)) { |
| struct btrfs_ordered_sum *sums = list_entry(ordered_sums.next, |
| struct btrfs_ordered_sum, |
| list); |
| if (!ret) |
| ret = btrfs_csum_file_blocks(trans, log, sums); |
| list_del(&sums->list); |
| kfree(sums); |
| } |
| return ret; |
| } |
| |
| /* log a single inode in the tree log. |
| * At least one parent directory for this inode must exist in the tree |
| * or be logged already. |
| * |
| * Any items from this inode changed by the current transaction are copied |
| * to the log tree. An extra reference is taken on any extents in this |
| * file, allowing us to avoid a whole pile of corner cases around logging |
| * blocks that have been removed from the tree. |
| * |
| * See LOG_INODE_ALL and related defines for a description of what inode_only |
| * does. |
| * |
| * This handles both files and directories. |
| */ |
| static int btrfs_log_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| int inode_only) |
| { |
| struct btrfs_path *path; |
| struct btrfs_path *dst_path; |
| struct btrfs_key min_key; |
| struct btrfs_key max_key; |
| struct btrfs_root *log = root->log_root; |
| struct extent_buffer *src = NULL; |
| int err = 0; |
| int ret; |
| int nritems; |
| int ins_start_slot = 0; |
| int ins_nr; |
| u64 ino = btrfs_ino(inode); |
| |
| log = root->log_root; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| dst_path = btrfs_alloc_path(); |
| if (!dst_path) { |
| btrfs_free_path(path); |
| return -ENOMEM; |
| } |
| |
| min_key.objectid = ino; |
| min_key.type = BTRFS_INODE_ITEM_KEY; |
| min_key.offset = 0; |
| |
| max_key.objectid = ino; |
| |
| /* today the code can only do partial logging of directories */ |
| if (!S_ISDIR(inode->i_mode)) |
| inode_only = LOG_INODE_ALL; |
| |
| if (inode_only == LOG_INODE_EXISTS || S_ISDIR(inode->i_mode)) |
| max_key.type = BTRFS_XATTR_ITEM_KEY; |
| else |
| max_key.type = (u8)-1; |
| max_key.offset = (u64)-1; |
| |
| ret = btrfs_commit_inode_delayed_items(trans, inode); |
| if (ret) { |
| btrfs_free_path(path); |
| btrfs_free_path(dst_path); |
| return ret; |
| } |
| |
| mutex_lock(&BTRFS_I(inode)->log_mutex); |
| |
| /* |
| * a brute force approach to making sure we get the most uptodate |
| * copies of everything. |
| */ |
| if (S_ISDIR(inode->i_mode)) { |
| int max_key_type = BTRFS_DIR_LOG_INDEX_KEY; |
| |
| if (inode_only == LOG_INODE_EXISTS) |
| max_key_type = BTRFS_XATTR_ITEM_KEY; |
| ret = drop_objectid_items(trans, log, path, ino, max_key_type); |
| } else { |
| ret = btrfs_truncate_inode_items(trans, log, inode, 0, 0); |
| } |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| path->keep_locks = 1; |
| |
| while (1) { |
| ins_nr = 0; |
| ret = btrfs_search_forward(root, &min_key, &max_key, |
| path, 0, trans->transid); |
| if (ret != 0) |
| break; |
| again: |
| /* note, ins_nr might be > 0 here, cleanup outside the loop */ |
| if (min_key.objectid != ino) |
| break; |
| if (min_key.type > max_key.type) |
| break; |
| |
| src = path->nodes[0]; |
| if (ins_nr && ins_start_slot + ins_nr == path->slots[0]) { |
| ins_nr++; |
| goto next_slot; |
| } else if (!ins_nr) { |
| ins_start_slot = path->slots[0]; |
| ins_nr = 1; |
| goto next_slot; |
| } |
| |
| ret = copy_items(trans, log, dst_path, src, ins_start_slot, |
| ins_nr, inode_only); |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| ins_nr = 1; |
| ins_start_slot = path->slots[0]; |
| next_slot: |
| |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| path->slots[0]++; |
| if (path->slots[0] < nritems) { |
| btrfs_item_key_to_cpu(path->nodes[0], &min_key, |
| path->slots[0]); |
| goto again; |
| } |
| if (ins_nr) { |
| ret = copy_items(trans, log, dst_path, src, |
| ins_start_slot, |
| ins_nr, inode_only); |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| ins_nr = 0; |
| } |
| btrfs_release_path(path); |
| |
| if (min_key.offset < (u64)-1) |
| min_key.offset++; |
| else if (min_key.type < (u8)-1) |
| min_key.type++; |
| else if (min_key.objectid < (u64)-1) |
| min_key.objectid++; |
| else |
| break; |
| } |
| if (ins_nr) { |
| ret = copy_items(trans, log, dst_path, src, |
| ins_start_slot, |
| ins_nr, inode_only); |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| ins_nr = 0; |
| } |
| WARN_ON(ins_nr); |
| if (inode_only == LOG_INODE_ALL && S_ISDIR(inode->i_mode)) { |
| btrfs_release_path(path); |
| btrfs_release_path(dst_path); |
| ret = log_directory_changes(trans, root, inode, path, dst_path); |
| if (ret) { |
| err = ret; |
| goto out_unlock; |
| } |
| } |
| BTRFS_I(inode)->logged_trans = trans->transid; |
| out_unlock: |
| mutex_unlock(&BTRFS_I(inode)->log_mutex); |
| |
| btrfs_free_path(path); |
| btrfs_free_path(dst_path); |
| return err; |
| } |
| |
| /* |
| * follow the dentry parent pointers up the chain and see if any |
| * of the directories in it require a full commit before they can |
| * be logged. Returns zero if nothing special needs to be done or 1 if |
| * a full commit is required. |
| */ |
| static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans, |
| struct inode *inode, |
| struct dentry *parent, |
| struct super_block *sb, |
| u64 last_committed) |
| { |
| int ret = 0; |
| struct btrfs_root *root; |
| struct dentry *old_parent = NULL; |
| |
| /* |
| * for regular files, if its inode is already on disk, we don't |
| * have to worry about the parents at all. This is because |
| * we can use the last_unlink_trans field to record renames |
| * and other fun in this file. |
| */ |
| if (S_ISREG(inode->i_mode) && |
| BTRFS_I(inode)->generation <= last_committed && |
| BTRFS_I(inode)->last_unlink_trans <= last_committed) |
| goto out; |
| |
| if (!S_ISDIR(inode->i_mode)) { |
| if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) |
| goto out; |
| inode = parent->d_inode; |
| } |
| |
| while (1) { |
| BTRFS_I(inode)->logged_trans = trans->transid; |
| smp_mb(); |
| |
| if (BTRFS_I(inode)->last_unlink_trans > last_committed) { |
| root = BTRFS_I(inode)->root; |
| |
| /* |
| * make sure any commits to the log are forced |
| * to be full commits |
| */ |
| root->fs_info->last_trans_log_full_commit = |
| trans->transid; |
| ret = 1; |
| break; |
| } |
| |
| if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) |
| break; |
| |
| if (IS_ROOT(parent)) |
| break; |
| |
| parent = dget_parent(parent); |
| dput(old_parent); |
| old_parent = parent; |
| inode = parent->d_inode; |
| |
| } |
| dput(old_parent); |
| out: |
| return ret; |
| } |
| |
| static int inode_in_log(struct btrfs_trans_handle *trans, |
| struct inode *inode) |
| { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| int ret = 0; |
| |
| mutex_lock(&root->log_mutex); |
| if (BTRFS_I(inode)->logged_trans == trans->transid && |
| BTRFS_I(inode)->last_sub_trans <= root->last_log_commit) |
| ret = 1; |
| mutex_unlock(&root->log_mutex); |
| return ret; |
| } |
| |
| |
| /* |
| * helper function around btrfs_log_inode to make sure newly created |
| * parent directories also end up in the log. A minimal inode and backref |
| * only logging is done of any parent directories that are older than |
| * the last committed transaction |
| */ |
| int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct inode *inode, |
| struct dentry *parent, int exists_only) |
| { |
| int inode_only = exists_only ? LOG_INODE_EXISTS : LOG_INODE_ALL; |
| struct super_block *sb; |
| struct dentry *old_parent = NULL; |
| int ret = 0; |
| u64 last_committed = root->fs_info->last_trans_committed; |
| |
| sb = inode->i_sb; |
| |
| if (btrfs_test_opt(root, NOTREELOG)) { |
| ret = 1; |
| goto end_no_trans; |
| } |
| |
| if (root->fs_info->last_trans_log_full_commit > |
| root->fs_info->last_trans_committed) { |
| ret = 1; |
| goto end_no_trans; |
| } |
| |
| if (root != BTRFS_I(inode)->root || |
| btrfs_root_refs(&root->root_item) == 0) { |
| ret = 1; |
| goto end_no_trans; |
| } |
| |
| ret = check_parent_dirs_for_sync(trans, inode, parent, |
| sb, last_committed); |
| if (ret) |
| goto end_no_trans; |
| |
| if (inode_in_log(trans, inode)) { |
| ret = BTRFS_NO_LOG_SYNC; |
| goto end_no_trans; |
| } |
| |
| ret = start_log_trans(trans, root); |
| if (ret) |
| goto end_trans; |
| |
| ret = btrfs_log_inode(trans, root, inode, inode_only); |
| if (ret) |
| goto end_trans; |
| |
| /* |
| * for regular files, if its inode is already on disk, we don't |
| * have to worry about the parents at all. This is because |
| * we can use the last_unlink_trans field to record renames |
| * and other fun in this file. |
| */ |
| if (S_ISREG(inode->i_mode) && |
| BTRFS_I(inode)->generation <= last_committed && |
| BTRFS_I(inode)->last_unlink_trans <= last_committed) { |
| ret = 0; |
| goto end_trans; |
| } |
| |
| inode_only = LOG_INODE_EXISTS; |
| while (1) { |
| if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb) |
| break; |
| |
| inode = parent->d_inode; |
| if (root != BTRFS_I(inode)->root) |
| break; |
| |
| if (BTRFS_I(inode)->generation > |
| root->fs_info->last_trans_committed) { |
| ret = btrfs_log_inode(trans, root, inode, inode_only); |
| if (ret) |
| goto end_trans; |
| } |
| if (IS_ROOT(parent)) |
| break; |
| |
| parent = dget_parent(parent); |
| dput(old_parent); |
| old_parent = parent; |
| } |
| ret = 0; |
| end_trans: |
| dput(old_parent); |
| if (ret < 0) { |
| BUG_ON(ret != -ENOSPC); |
| root->fs_info->last_trans_log_full_commit = trans->transid; |
| ret = 1; |
| } |
| btrfs_end_log_trans(root); |
| end_no_trans: |
| return ret; |
| } |
| |
| /* |
| * it is not safe to log dentry if the chunk root has added new |
| * chunks. This returns 0 if the dentry was logged, and 1 otherwise. |
| * If this returns 1, you must commit the transaction to safely get your |
| * data on disk. |
| */ |
| int btrfs_log_dentry_safe(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct dentry *dentry) |
| { |
| struct dentry *parent = dget_parent(dentry); |
| int ret; |
| |
| ret = btrfs_log_inode_parent(trans, root, dentry->d_inode, parent, 0); |
| dput(parent); |
| |
| return ret; |
| } |
| |
| /* |
| * should be called during mount to recover any replay any log trees |
| * from the FS |
| */ |
| int btrfs_recover_log_trees(struct btrfs_root *log_root_tree) |
| { |
| int ret; |
| struct btrfs_path *path; |
| struct btrfs_trans_handle *trans; |
| struct btrfs_key key; |
| struct btrfs_key found_key; |
| struct btrfs_key tmp_key; |
| struct btrfs_root *log; |
| struct btrfs_fs_info *fs_info = log_root_tree->fs_info; |
| struct walk_control wc = { |
| .process_func = process_one_buffer, |
| .stage = 0, |
| }; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| fs_info->log_root_recovering = 1; |
| |
| trans = btrfs_start_transaction(fs_info->tree_root, 0); |
| BUG_ON(IS_ERR(trans)); |
| |
| wc.trans = trans; |
| wc.pin = 1; |
| |
| ret = walk_log_tree(trans, log_root_tree, &wc); |
| BUG_ON(ret); |
| |
| again: |
| key.objectid = BTRFS_TREE_LOG_OBJECTID; |
| key.offset = (u64)-1; |
| btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); |
| |
| while (1) { |
| ret = btrfs_search_slot(NULL, log_root_tree, &key, path, 0, 0); |
| if (ret < 0) |
| break; |
| if (ret > 0) { |
| if (path->slots[0] == 0) |
| break; |
| path->slots[0]--; |
| } |
| btrfs_item_key_to_cpu(path->nodes[0], &found_key, |
| path->slots[0]); |
| btrfs_release_path(path); |
| if (found_key.objectid != BTRFS_TREE_LOG_OBJECTID) |
| break; |
| |
| log = btrfs_read_fs_root_no_radix(log_root_tree, |
| &found_key); |
| BUG_ON(IS_ERR(log)); |
| |
| tmp_key.objectid = found_key.offset; |
| tmp_key.type = BTRFS_ROOT_ITEM_KEY; |
| tmp_key.offset = (u64)-1; |
| |
| wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key); |
| BUG_ON(IS_ERR_OR_NULL(wc.replay_dest)); |
| |
| wc.replay_dest->log_root = log; |
| btrfs_record_root_in_trans(trans, wc.replay_dest); |
| ret = walk_log_tree(trans, log, &wc); |
| BUG_ON(ret); |
| |
| if (wc.stage == LOG_WALK_REPLAY_ALL) { |
| ret = fixup_inode_link_counts(trans, wc.replay_dest, |
| path); |
| BUG_ON(ret); |
| } |
| |
| key.offset = found_key.offset - 1; |
| wc.replay_dest->log_root = NULL; |
| free_extent_buffer(log->node); |
| free_extent_buffer(log->commit_root); |
| kfree(log); |
| |
| if (found_key.offset == 0) |
| break; |
| } |
| btrfs_release_path(path); |
| |
| /* step one is to pin it all, step two is to replay just inodes */ |
| if (wc.pin) { |
| wc.pin = 0; |
| wc.process_func = replay_one_buffer; |
| wc.stage = LOG_WALK_REPLAY_INODES; |
| goto again; |
| } |
| /* step three is to replay everything */ |
| if (wc.stage < LOG_WALK_REPLAY_ALL) { |
| wc.stage++; |
| goto again; |
| } |
| |
| btrfs_free_path(path); |
| |
| free_extent_buffer(log_root_tree->node); |
| log_root_tree->log_root = NULL; |
| fs_info->log_root_recovering = 0; |
| |
| /* step 4: commit the transaction, which also unpins the blocks */ |
| btrfs_commit_transaction(trans, fs_info->tree_root); |
| |
| kfree(log_root_tree); |
| return 0; |
| } |
| |
| /* |
| * there are some corner cases where we want to force a full |
| * commit instead of allowing a directory to be logged. |
| * |
| * They revolve around files there were unlinked from the directory, and |
| * this function updates the parent directory so that a full commit is |
| * properly done if it is fsync'd later after the unlinks are done. |
| */ |
| void btrfs_record_unlink_dir(struct btrfs_trans_handle *trans, |
| struct inode *dir, struct inode *inode, |
| int for_rename) |
| { |
| /* |
| * when we're logging a file, if it hasn't been renamed |
| * or unlinked, and its inode is fully committed on disk, |
| * we don't have to worry about walking up the directory chain |
| * to log its parents. |
| * |
| * So, we use the last_unlink_trans field to put this transid |
| * into the file. When the file is logged we check it and |
| * don't log the parents if the file is fully on disk. |
| */ |
| if (S_ISREG(inode->i_mode)) |
| BTRFS_I(inode)->last_unlink_trans = trans->transid; |
| |
| /* |
| * if this directory was already logged any new |
| * names for this file/dir will get recorded |
| */ |
| smp_mb(); |
| if (BTRFS_I(dir)->logged_trans == trans->transid) |
| return; |
| |
| /* |
| * if the inode we're about to unlink was logged, |
| * the log will be properly updated for any new names |
| */ |
| if (BTRFS_I(inode)->logged_trans == trans->transid) |
| return; |
| |
| /* |
| * when renaming files across directories, if the directory |
| * there we're unlinking from gets fsync'd later on, there's |
| * no way to find the destination directory later and fsync it |
| * properly. So, we have to be conservative and force commits |
| * so the new name gets discovered. |
| */ |
| if (for_rename) |
| goto record; |
| |
| /* we can safely do the unlink without any special recording */ |
| return; |
| |
| record: |
| BTRFS_I(dir)->last_unlink_trans = trans->transid; |
| } |
| |
| /* |
| * Call this after adding a new name for a file and it will properly |
| * update the log to reflect the new name. |
| * |
| * It will return zero if all goes well, and it will return 1 if a |
| * full transaction commit is required. |
| */ |
| int btrfs_log_new_name(struct btrfs_trans_handle *trans, |
| struct inode *inode, struct inode *old_dir, |
| struct dentry *parent) |
| { |
| struct btrfs_root * root = BTRFS_I(inode)->root; |
| |
| /* |
| * this will force the logging code to walk the dentry chain |
| * up for the file |
| */ |
| if (S_ISREG(inode->i_mode)) |
| BTRFS_I(inode)->last_unlink_trans = trans->transid; |
| |
| /* |
| * if this inode hasn't been logged and directory we're renaming it |
| * from hasn't been logged, we don't need to log it |
| */ |
| if (BTRFS_I(inode)->logged_trans <= |
| root->fs_info->last_trans_committed && |
| (!old_dir || BTRFS_I(old_dir)->logged_trans <= |
| root->fs_info->last_trans_committed)) |
| return 0; |
| |
| return btrfs_log_inode_parent(trans, root, inode, parent, 1); |
| } |
| |