| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2008 Oracle. All rights reserved. |
| */ |
| |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/blkdev.h> |
| #include <linux/list_sort.h> |
| #include <linux/iversion.h> |
| #include "ctree.h" |
| #include "tree-log.h" |
| #include "disk-io.h" |
| #include "locking.h" |
| #include "print-tree.h" |
| #include "backref.h" |
| #include "compression.h" |
| #include "qgroup.h" |
| #include "inode-map.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 |
| #define LOG_OTHER_INODE 2 |
| |
| /* |
| * 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_DIR_INDEX 2 |
| #define LOG_WALK_REPLAY_ALL 3 |
| |
| static int btrfs_log_inode(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, struct btrfs_inode *inode, |
| int inode_only, |
| const loff_t start, |
| const loff_t end, |
| struct btrfs_log_ctx *ctx); |
| 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, |
| struct btrfs_log_ctx *ctx) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| int ret = 0; |
| |
| mutex_lock(&root->log_mutex); |
| |
| if (root->log_root) { |
| if (btrfs_need_log_full_commit(fs_info, trans)) { |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| if (!root->log_start_pid) { |
| clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); |
| root->log_start_pid = current->pid; |
| } else if (root->log_start_pid != current->pid) { |
| set_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); |
| } |
| } else { |
| mutex_lock(&fs_info->tree_log_mutex); |
| if (!fs_info->log_root_tree) |
| ret = btrfs_init_log_root_tree(trans, fs_info); |
| mutex_unlock(&fs_info->tree_log_mutex); |
| if (ret) |
| goto out; |
| |
| ret = btrfs_add_log_tree(trans, root); |
| if (ret) |
| goto out; |
| |
| clear_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state); |
| root->log_start_pid = current->pid; |
| } |
| |
| atomic_inc(&root->log_batch); |
| atomic_inc(&root->log_writers); |
| if (ctx) { |
| int index = root->log_transid % 2; |
| list_add_tail(&ctx->list, &root->log_ctxs[index]); |
| ctx->log_transid = root->log_transid; |
| } |
| |
| out: |
| mutex_unlock(&root->log_mutex); |
| return ret; |
| } |
| |
| /* |
| * 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 |
| */ |
| void btrfs_end_log_trans(struct btrfs_root *root) |
| { |
| if (atomic_dec_and_test(&root->log_writers)) { |
| /* atomic_dec_and_test implies a barrier */ |
| cond_wake_up_nomb(&root->log_writer_wait); |
| } |
| } |
| |
| |
| /* |
| * 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; |
| |
| /* |
| * Ignore any items from the inode currently being processed. Needs |
| * to be set every time we find a BTRFS_INODE_ITEM_KEY and we are in |
| * the LOG_WALK_REPLAY_INODES stage. |
| */ |
| bool ignore_cur_inode; |
| |
| /* 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, int level); |
| }; |
| |
| /* |
| * 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, int level) |
| { |
| struct btrfs_fs_info *fs_info = log->fs_info; |
| int ret = 0; |
| |
| /* |
| * If this fs is mixed then we need to be able to process the leaves to |
| * pin down any logged extents, so we have to read the block. |
| */ |
| if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) { |
| ret = btrfs_read_buffer(eb, gen, level, NULL); |
| if (ret) |
| return ret; |
| } |
| |
| if (wc->pin) |
| ret = btrfs_pin_extent_for_log_replay(fs_info, eb->start, |
| eb->len); |
| |
| if (!ret && btrfs_buffer_uptodate(eb, gen, 0)) { |
| if (wc->pin && btrfs_header_level(eb) == 0) |
| ret = btrfs_exclude_logged_extents(fs_info, eb); |
| if (wc->write) |
| btrfs_write_tree_block(eb); |
| if (wc->wait) |
| btrfs_wait_tree_block_writeback(eb); |
| } |
| return ret; |
| } |
| |
| /* |
| * 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) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| 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; |
| bool inode_item = key->type == BTRFS_INODE_ITEM_KEY; |
| |
| 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) |
| return ret; |
| |
| 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; |
| } |
| |
| /* |
| * We need to load the old nbytes into the inode so when we |
| * replay the extents we've logged we get the right nbytes. |
| */ |
| if (inode_item) { |
| struct btrfs_inode_item *item; |
| u64 nbytes; |
| u32 mode; |
| |
| item = btrfs_item_ptr(path->nodes[0], path->slots[0], |
| struct btrfs_inode_item); |
| nbytes = btrfs_inode_nbytes(path->nodes[0], item); |
| item = btrfs_item_ptr(eb, slot, |
| struct btrfs_inode_item); |
| btrfs_set_inode_nbytes(eb, item, nbytes); |
| |
| /* |
| * If this is a directory we need to reset the i_size to |
| * 0 so that we can set it up properly when replaying |
| * the rest of the items in this log. |
| */ |
| mode = btrfs_inode_mode(eb, item); |
| if (S_ISDIR(mode)) |
| btrfs_set_inode_size(eb, item, 0); |
| } |
| } else if (inode_item) { |
| struct btrfs_inode_item *item; |
| u32 mode; |
| |
| /* |
| * New inode, set nbytes to 0 so that the nbytes comes out |
| * properly when we replay the extents. |
| */ |
| item = btrfs_item_ptr(eb, slot, struct btrfs_inode_item); |
| btrfs_set_inode_nbytes(eb, item, 0); |
| |
| /* |
| * If this is a directory we need to reset the i_size to 0 so |
| * that we can set it up properly when replaying the rest of |
| * the items in this log. |
| */ |
| mode = btrfs_inode_mode(eb, item); |
| if (S_ISDIR(mode)) |
| btrfs_set_inode_size(eb, item, 0); |
| } |
| insert: |
| btrfs_release_path(path); |
| /* try to insert the key into the destination tree */ |
| path->skip_release_on_error = 1; |
| ret = btrfs_insert_empty_item(trans, root, path, |
| key, item_size); |
| path->skip_release_on_error = 0; |
| |
| /* make sure any existing item is the correct size */ |
| if (ret == -EEXIST || ret == -EOVERFLOW) { |
| u32 found_size; |
| found_size = btrfs_item_size_nr(path->nodes[0], |
| path->slots[0]); |
| if (found_size > item_size) |
| btrfs_truncate_item(fs_info, path, item_size, 1); |
| else if (found_size < item_size) |
| btrfs_extend_item(fs_info, 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) { |
| struct extent_buffer *dst_eb = path->nodes[0]; |
| const u64 ino_size = btrfs_inode_size(eb, src_item); |
| |
| /* |
| * For regular files an ino_size == 0 is used only when |
| * logging that an inode exists, as part of a directory |
| * fsync, and the inode wasn't fsynced before. In this |
| * case don't set the size of the inode in the fs/subvol |
| * tree, otherwise we would be throwing valid data away. |
| */ |
| if (S_ISREG(btrfs_inode_mode(eb, src_item)) && |
| S_ISREG(btrfs_inode_mode(dst_eb, dst_item)) && |
| ino_size != 0) { |
| struct btrfs_map_token token; |
| |
| btrfs_init_map_token(&token); |
| btrfs_set_token_inode_size(dst_eb, dst_item, |
| ino_size, &token); |
| } |
| 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; |
| 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) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| int found_type; |
| u64 extent_end; |
| u64 start = key->offset; |
| u64 nbytes = 0; |
| 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) { |
| nbytes = btrfs_file_extent_num_bytes(eb, item); |
| extent_end = start + nbytes; |
| |
| /* |
| * We don't add to the inodes nbytes if we are prealloc or a |
| * hole. |
| */ |
| if (btrfs_file_extent_disk_bytenr(eb, item) == 0) |
| nbytes = 0; |
| } else if (found_type == BTRFS_FILE_EXTENT_INLINE) { |
| size = btrfs_file_extent_ram_bytes(eb, item); |
| nbytes = btrfs_file_extent_ram_bytes(eb, item); |
| extent_end = ALIGN(start + size, |
| fs_info->sectorsize); |
| } 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(BTRFS_I(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); |
| |
| /* drop any overlapping extents */ |
| ret = btrfs_drop_extents(trans, root, inode, start, extent_end, 1); |
| if (ret) |
| goto out; |
| |
| if (found_type == BTRFS_FILE_EXTENT_REG || |
| found_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| u64 offset; |
| unsigned long dest_offset; |
| struct btrfs_key ins; |
| |
| if (btrfs_file_extent_disk_bytenr(eb, item) == 0 && |
| btrfs_fs_incompat(fs_info, NO_HOLES)) |
| goto update_inode; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, key, |
| sizeof(*item)); |
| if (ret) |
| goto out; |
| 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); |
| |
| /* |
| * Manually record dirty extent, as here we did a shallow |
| * file extent item copy and skip normal backref update, |
| * but modifying extent tree all by ourselves. |
| * So need to manually record dirty extent for qgroup, |
| * as the owner of the file extent changed from log tree |
| * (doesn't affect qgroup) to fs/file tree(affects qgroup) |
| */ |
| ret = btrfs_qgroup_trace_extent(trans, |
| btrfs_file_extent_disk_bytenr(eb, item), |
| btrfs_file_extent_disk_num_bytes(eb, item), |
| GFP_NOFS); |
| if (ret < 0) |
| goto out; |
| |
| 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_data_extent(fs_info, 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); |
| if (ret) |
| goto out; |
| } else { |
| /* |
| * insert the extent pointer in the extent |
| * allocation tree |
| */ |
| ret = btrfs_alloc_logged_file_extent(trans, |
| root->root_key.objectid, |
| key->objectid, offset, &ins); |
| if (ret) |
| goto out; |
| } |
| 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); |
| if (ret) |
| goto out; |
| /* |
| * Now delete all existing cums in the csum root that |
| * cover our range. We do this because we can have an |
| * extent that is completely referenced by one file |
| * extent item and partially referenced by another |
| * file extent item (like after using the clone or |
| * extent_same ioctls). In this case if we end up doing |
| * the replay of the one that partially references the |
| * extent first, and we do not do the csum deletion |
| * below, we can get 2 csum items in the csum tree that |
| * overlap each other. For example, imagine our log has |
| * the two following file extent items: |
| * |
| * key (257 EXTENT_DATA 409600) |
| * extent data disk byte 12845056 nr 102400 |
| * extent data offset 20480 nr 20480 ram 102400 |
| * |
| * key (257 EXTENT_DATA 819200) |
| * extent data disk byte 12845056 nr 102400 |
| * extent data offset 0 nr 102400 ram 102400 |
| * |
| * Where the second one fully references the 100K extent |
| * that starts at disk byte 12845056, and the log tree |
| * has a single csum item that covers the entire range |
| * of the extent: |
| * |
| * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100 |
| * |
| * After the first file extent item is replayed, the |
| * csum tree gets the following csum item: |
| * |
| * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20 |
| * |
| * Which covers the 20K sub-range starting at offset 20K |
| * of our extent. Now when we replay the second file |
| * extent item, if we do not delete existing csum items |
| * that cover any of its blocks, we end up getting two |
| * csum items in our csum tree that overlap each other: |
| * |
| * key (EXTENT_CSUM EXTENT_CSUM 12845056) itemsize 100 |
| * key (EXTENT_CSUM EXTENT_CSUM 12865536) itemsize 20 |
| * |
| * Which is a problem, because after this anyone trying |
| * to lookup up for the checksum of any block of our |
| * extent starting at an offset of 40K or higher, will |
| * end up looking at the second csum item only, which |
| * does not contain the checksum for any block starting |
| * at offset 40K or higher of our extent. |
| */ |
| while (!list_empty(&ordered_sums)) { |
| struct btrfs_ordered_sum *sums; |
| sums = list_entry(ordered_sums.next, |
| struct btrfs_ordered_sum, |
| list); |
| if (!ret) |
| ret = btrfs_del_csums(trans, |
| fs_info->csum_root, |
| sums->bytenr, |
| sums->len); |
| if (!ret) |
| ret = btrfs_csum_file_blocks(trans, |
| fs_info->csum_root, sums); |
| list_del(&sums->list); |
| kfree(sums); |
| } |
| if (ret) |
| goto out; |
| } 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); |
| if (ret) |
| goto out; |
| } |
| |
| inode_add_bytes(inode, nbytes); |
| update_inode: |
| ret = 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 btrfs_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) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| ret = link_to_fixup_dir(trans, root, path, location.objectid); |
| if (ret) |
| goto out; |
| |
| ret = btrfs_unlink_inode(trans, root, dir, BTRFS_I(inode), name, |
| name_len); |
| if (ret) |
| goto out; |
| else |
| ret = btrfs_run_delayed_items(trans); |
| out: |
| 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, |
| u64 ref_objectid, |
| const 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; |
| |
| ptr = btrfs_item_ptr_offset(path->nodes[0], path->slots[0]); |
| |
| if (key->type == BTRFS_INODE_EXTREF_KEY) { |
| if (btrfs_find_name_in_ext_backref(path->nodes[0], |
| path->slots[0], |
| ref_objectid, |
| name, namelen, NULL)) |
| match = 1; |
| |
| goto out; |
| } |
| |
| item_size = btrfs_item_size_nr(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; |
| } |
| |
| static inline int __add_inode_ref(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct btrfs_root *log_root, |
| struct btrfs_inode *dir, |
| struct btrfs_inode *inode, |
| u64 inode_objectid, u64 parent_objectid, |
| u64 ref_index, char *name, int namelen, |
| int *search_done) |
| { |
| int ret; |
| char *victim_name; |
| int victim_name_len; |
| struct extent_buffer *leaf; |
| struct btrfs_dir_item *di; |
| struct btrfs_key search_key; |
| struct btrfs_inode_extref *extref; |
| |
| again: |
| /* Search old style refs */ |
| search_key.objectid = inode_objectid; |
| search_key.type = BTRFS_INODE_REF_KEY; |
| search_key.offset = parent_objectid; |
| ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0); |
| if (ret == 0) { |
| struct btrfs_inode_ref *victim_ref; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| |
| 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 (search_key.objectid == search_key.offset) |
| return 1; |
| |
| /* 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); |
| if (!victim_name) |
| return -ENOMEM; |
| |
| read_extent_buffer(leaf, victim_name, |
| (unsigned long)(victim_ref + 1), |
| victim_name_len); |
| |
| if (!backref_in_log(log_root, &search_key, |
| parent_objectid, |
| victim_name, |
| victim_name_len)) { |
| inc_nlink(&inode->vfs_inode); |
| btrfs_release_path(path); |
| |
| ret = btrfs_unlink_inode(trans, root, dir, inode, |
| victim_name, victim_name_len); |
| kfree(victim_name); |
| if (ret) |
| return ret; |
| ret = btrfs_run_delayed_items(trans); |
| if (ret) |
| return ret; |
| *search_done = 1; |
| goto again; |
| } |
| kfree(victim_name); |
| |
| ptr = (unsigned long)(victim_ref + 1) + victim_name_len; |
| } |
| |
| /* |
| * NOTE: we have searched root tree and checked the |
| * corresponding ref, it does not need to check again. |
| */ |
| *search_done = 1; |
| } |
| btrfs_release_path(path); |
| |
| /* Same search but for extended refs */ |
| extref = btrfs_lookup_inode_extref(NULL, root, path, name, namelen, |
| inode_objectid, parent_objectid, 0, |
| 0); |
| if (!IS_ERR_OR_NULL(extref)) { |
| u32 item_size; |
| u32 cur_offset = 0; |
| unsigned long base; |
| struct inode *victim_parent; |
| |
| leaf = path->nodes[0]; |
| |
| item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
| base = btrfs_item_ptr_offset(leaf, path->slots[0]); |
| |
| while (cur_offset < item_size) { |
| extref = (struct btrfs_inode_extref *)(base + cur_offset); |
| |
| victim_name_len = btrfs_inode_extref_name_len(leaf, extref); |
| |
| if (btrfs_inode_extref_parent(leaf, extref) != parent_objectid) |
| goto next; |
| |
| victim_name = kmalloc(victim_name_len, GFP_NOFS); |
| if (!victim_name) |
| return -ENOMEM; |
| read_extent_buffer(leaf, victim_name, (unsigned long)&extref->name, |
| victim_name_len); |
| |
| search_key.objectid = inode_objectid; |
| search_key.type = BTRFS_INODE_EXTREF_KEY; |
| search_key.offset = btrfs_extref_hash(parent_objectid, |
| victim_name, |
| victim_name_len); |
| ret = 0; |
| if (!backref_in_log(log_root, &search_key, |
| parent_objectid, victim_name, |
| victim_name_len)) { |
| ret = -ENOENT; |
| victim_parent = read_one_inode(root, |
| parent_objectid); |
| if (victim_parent) { |
| inc_nlink(&inode->vfs_inode); |
| btrfs_release_path(path); |
| |
| ret = btrfs_unlink_inode(trans, root, |
| BTRFS_I(victim_parent), |
| inode, |
| victim_name, |
| victim_name_len); |
| if (!ret) |
| ret = btrfs_run_delayed_items( |
| trans); |
| } |
| iput(victim_parent); |
| kfree(victim_name); |
| if (ret) |
| return ret; |
| *search_done = 1; |
| goto again; |
| } |
| kfree(victim_name); |
| next: |
| cur_offset += victim_name_len + sizeof(*extref); |
| } |
| *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), |
| ref_index, name, namelen, 0); |
| if (di && !IS_ERR(di)) { |
| ret = drop_one_dir_item(trans, root, path, dir, di); |
| if (ret) |
| return 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); |
| if (ret) |
| return ret; |
| } |
| btrfs_release_path(path); |
| |
| return 0; |
| } |
| |
| static int extref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr, |
| u32 *namelen, char **name, u64 *index, |
| u64 *parent_objectid) |
| { |
| struct btrfs_inode_extref *extref; |
| |
| extref = (struct btrfs_inode_extref *)ref_ptr; |
| |
| *namelen = btrfs_inode_extref_name_len(eb, extref); |
| *name = kmalloc(*namelen, GFP_NOFS); |
| if (*name == NULL) |
| return -ENOMEM; |
| |
| read_extent_buffer(eb, *name, (unsigned long)&extref->name, |
| *namelen); |
| |
| if (index) |
| *index = btrfs_inode_extref_index(eb, extref); |
| if (parent_objectid) |
| *parent_objectid = btrfs_inode_extref_parent(eb, extref); |
| |
| return 0; |
| } |
| |
| static int ref_get_fields(struct extent_buffer *eb, unsigned long ref_ptr, |
| u32 *namelen, char **name, u64 *index) |
| { |
| struct btrfs_inode_ref *ref; |
| |
| ref = (struct btrfs_inode_ref *)ref_ptr; |
| |
| *namelen = btrfs_inode_ref_name_len(eb, ref); |
| *name = kmalloc(*namelen, GFP_NOFS); |
| if (*name == NULL) |
| return -ENOMEM; |
| |
| read_extent_buffer(eb, *name, (unsigned long)(ref + 1), *namelen); |
| |
| if (index) |
| *index = btrfs_inode_ref_index(eb, ref); |
| |
| return 0; |
| } |
| |
| /* |
| * Take an inode reference item from the log tree and iterate all names from the |
| * inode reference item in the subvolume tree with the same key (if it exists). |
| * For any name that is not in the inode reference item from the log tree, do a |
| * proper unlink of that name (that is, remove its entry from the inode |
| * reference item and both dir index keys). |
| */ |
| static int unlink_old_inode_refs(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_path *path, |
| struct btrfs_inode *inode, |
| struct extent_buffer *log_eb, |
| int log_slot, |
| struct btrfs_key *key) |
| { |
| int ret; |
| unsigned long ref_ptr; |
| unsigned long ref_end; |
| struct extent_buffer *eb; |
| |
| again: |
| btrfs_release_path(path); |
| ret = btrfs_search_slot(NULL, root, key, path, 0, 0); |
| if (ret > 0) { |
| ret = 0; |
| goto out; |
| } |
| if (ret < 0) |
| goto out; |
| |
| eb = path->nodes[0]; |
| ref_ptr = btrfs_item_ptr_offset(eb, path->slots[0]); |
| ref_end = ref_ptr + btrfs_item_size_nr(eb, path->slots[0]); |
| while (ref_ptr < ref_end) { |
| char *name = NULL; |
| int namelen; |
| u64 parent_id; |
| |
| if (key->type == BTRFS_INODE_EXTREF_KEY) { |
| ret = extref_get_fields(eb, ref_ptr, &namelen, &name, |
| NULL, &parent_id); |
| } else { |
| parent_id = key->offset; |
| ret = ref_get_fields(eb, ref_ptr, &namelen, &name, |
| NULL); |
| } |
| if (ret) |
| goto out; |
| |
| if (key->type == BTRFS_INODE_EXTREF_KEY) |
| ret = btrfs_find_name_in_ext_backref(log_eb, log_slot, |
| parent_id, name, |
| namelen, NULL); |
| else |
| ret = btrfs_find_name_in_backref(log_eb, log_slot, name, |
| namelen, NULL); |
| |
| if (!ret) { |
| struct inode *dir; |
| |
| btrfs_release_path(path); |
| dir = read_one_inode(root, parent_id); |
| if (!dir) { |
| ret = -ENOENT; |
| kfree(name); |
| goto out; |
| } |
| ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir), |
| inode, name, namelen); |
| kfree(name); |
| iput(dir); |
| if (ret) |
| goto out; |
| goto again; |
| } |
| |
| kfree(name); |
| ref_ptr += namelen; |
| if (key->type == BTRFS_INODE_EXTREF_KEY) |
| ref_ptr += sizeof(struct btrfs_inode_extref); |
| else |
| ref_ptr += sizeof(struct btrfs_inode_ref); |
| } |
| ret = 0; |
| out: |
| btrfs_release_path(path); |
| return ret; |
| } |
| |
| static int btrfs_inode_ref_exists(struct inode *inode, struct inode *dir, |
| const u8 ref_type, const char *name, |
| const int namelen) |
| { |
| struct btrfs_key key; |
| struct btrfs_path *path; |
| const u64 parent_id = btrfs_ino(BTRFS_I(dir)); |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| key.objectid = btrfs_ino(BTRFS_I(inode)); |
| key.type = ref_type; |
| if (key.type == BTRFS_INODE_REF_KEY) |
| key.offset = parent_id; |
| else |
| key.offset = btrfs_extref_hash(parent_id, name, namelen); |
| |
| ret = btrfs_search_slot(NULL, BTRFS_I(inode)->root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| if (ret > 0) { |
| ret = 0; |
| goto out; |
| } |
| if (key.type == BTRFS_INODE_EXTREF_KEY) |
| ret = btrfs_find_name_in_ext_backref(path->nodes[0], |
| path->slots[0], parent_id, |
| name, namelen, NULL); |
| else |
| ret = btrfs_find_name_in_backref(path->nodes[0], path->slots[0], |
| name, namelen, NULL); |
| |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| /* |
| * 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 inode *dir = NULL; |
| struct inode *inode = NULL; |
| unsigned long ref_ptr; |
| unsigned long ref_end; |
| char *name = NULL; |
| int namelen; |
| int ret; |
| int search_done = 0; |
| int log_ref_ver = 0; |
| u64 parent_objectid; |
| u64 inode_objectid; |
| u64 ref_index = 0; |
| int ref_struct_size; |
| |
| ref_ptr = btrfs_item_ptr_offset(eb, slot); |
| ref_end = ref_ptr + btrfs_item_size_nr(eb, slot); |
| |
| if (key->type == BTRFS_INODE_EXTREF_KEY) { |
| struct btrfs_inode_extref *r; |
| |
| ref_struct_size = sizeof(struct btrfs_inode_extref); |
| log_ref_ver = 1; |
| r = (struct btrfs_inode_extref *)ref_ptr; |
| parent_objectid = btrfs_inode_extref_parent(eb, r); |
| } else { |
| ref_struct_size = sizeof(struct btrfs_inode_ref); |
| parent_objectid = key->offset; |
| } |
| inode_objectid = key->objectid; |
| |
| /* |
| * 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, parent_objectid); |
| if (!dir) { |
| ret = -ENOENT; |
| goto out; |
| } |
| |
| inode = read_one_inode(root, inode_objectid); |
| if (!inode) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| while (ref_ptr < ref_end) { |
| if (log_ref_ver) { |
| ret = extref_get_fields(eb, ref_ptr, &namelen, &name, |
| &ref_index, &parent_objectid); |
| /* |
| * parent object can change from one array |
| * item to another. |
| */ |
| if (!dir) |
| dir = read_one_inode(root, parent_objectid); |
| if (!dir) { |
| ret = -ENOENT; |
| goto out; |
| } |
| } else { |
| ret = ref_get_fields(eb, ref_ptr, &namelen, &name, |
| &ref_index); |
| } |
| if (ret) |
| goto out; |
| |
| /* if we already have a perfect match, we're done */ |
| if (!inode_in_dir(root, path, btrfs_ino(BTRFS_I(dir)), |
| btrfs_ino(BTRFS_I(inode)), ref_index, |
| name, namelen)) { |
| /* |
| * 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) { |
| ret = __add_inode_ref(trans, root, path, log, |
| BTRFS_I(dir), |
| BTRFS_I(inode), |
| inode_objectid, |
| parent_objectid, |
| ref_index, name, namelen, |
| &search_done); |
| if (ret) { |
| if (ret == 1) |
| ret = 0; |
| goto out; |
| } |
| } |
| |
| /* |
| * If a reference item already exists for this inode |
| * with the same parent and name, but different index, |
| * drop it and the corresponding directory index entries |
| * from the parent before adding the new reference item |
| * and dir index entries, otherwise we would fail with |
| * -EEXIST returned from btrfs_add_link() below. |
| */ |
| ret = btrfs_inode_ref_exists(inode, dir, key->type, |
| name, namelen); |
| if (ret > 0) { |
| ret = btrfs_unlink_inode(trans, root, |
| BTRFS_I(dir), |
| BTRFS_I(inode), |
| name, namelen); |
| /* |
| * If we dropped the link count to 0, bump it so |
| * that later the iput() on the inode will not |
| * free it. We will fixup the link count later. |
| */ |
| if (!ret && inode->i_nlink == 0) |
| inc_nlink(inode); |
| } |
| if (ret < 0) |
| goto out; |
| |
| /* insert our name */ |
| ret = btrfs_add_link(trans, BTRFS_I(dir), |
| BTRFS_I(inode), |
| name, namelen, 0, ref_index); |
| if (ret) |
| goto out; |
| |
| btrfs_update_inode(trans, root, inode); |
| } |
| |
| ref_ptr = (unsigned long)(ref_ptr + ref_struct_size) + namelen; |
| kfree(name); |
| name = NULL; |
| if (log_ref_ver) { |
| iput(dir); |
| dir = NULL; |
| } |
| } |
| |
| /* |
| * Before we overwrite the inode reference item in the subvolume tree |
| * with the item from the log tree, we must unlink all names from the |
| * parent directory that are in the subvolume's tree inode reference |
| * item, otherwise we end up with an inconsistent subvolume tree where |
| * dir index entries exist for a name but there is no inode reference |
| * item with the same name. |
| */ |
| ret = unlink_old_inode_refs(trans, root, path, BTRFS_I(inode), eb, slot, |
| key); |
| if (ret) |
| goto out; |
| |
| /* finally write the back reference in the inode */ |
| ret = overwrite_item(trans, root, path, eb, slot, key); |
| out: |
| btrfs_release_path(path); |
| kfree(name); |
| iput(dir); |
| iput(inode); |
| return ret; |
| } |
| |
| static int insert_orphan_item(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, u64 ino) |
| { |
| int ret; |
| |
| ret = btrfs_insert_orphan_item(trans, root, ino); |
| if (ret == -EEXIST) |
| ret = 0; |
| |
| return ret; |
| } |
| |
| static int count_inode_extrefs(struct btrfs_root *root, |
| struct btrfs_inode *inode, struct btrfs_path *path) |
| { |
| int ret = 0; |
| int name_len; |
| unsigned int nlink = 0; |
| u32 item_size; |
| u32 cur_offset = 0; |
| u64 inode_objectid = btrfs_ino(inode); |
| u64 offset = 0; |
| unsigned long ptr; |
| struct btrfs_inode_extref *extref; |
| struct extent_buffer *leaf; |
| |
| while (1) { |
| ret = btrfs_find_one_extref(root, inode_objectid, offset, path, |
| &extref, &offset); |
| if (ret) |
| break; |
| |
| leaf = path->nodes[0]; |
| item_size = btrfs_item_size_nr(leaf, path->slots[0]); |
| ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); |
| cur_offset = 0; |
| |
| while (cur_offset < item_size) { |
| extref = (struct btrfs_inode_extref *) (ptr + cur_offset); |
| name_len = btrfs_inode_extref_name_len(leaf, extref); |
| |
| nlink++; |
| |
| cur_offset += name_len + sizeof(*extref); |
| } |
| |
| offset++; |
| btrfs_release_path(path); |
| } |
| btrfs_release_path(path); |
| |
| if (ret < 0 && ret != -ENOENT) |
| return ret; |
| return nlink; |
| } |
| |
| static int count_inode_refs(struct btrfs_root *root, |
| struct btrfs_inode *inode, struct btrfs_path *path) |
| { |
| int ret; |
| struct btrfs_key key; |
| unsigned int 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; |
| |
| 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]--; |
| } |
| process_slot: |
| 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; |
| if (path->slots[0] > 0) { |
| path->slots[0]--; |
| goto process_slot; |
| } |
| key.offset--; |
| btrfs_release_path(path); |
| } |
| btrfs_release_path(path); |
| |
| return nlink; |
| } |
| |
| /* |
| * 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; |
| u64 nlink = 0; |
| u64 ino = btrfs_ino(BTRFS_I(inode)); |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| ret = count_inode_refs(root, BTRFS_I(inode), path); |
| if (ret < 0) |
| goto out; |
| |
| nlink = ret; |
| |
| ret = count_inode_extrefs(root, BTRFS_I(inode), path); |
| if (ret < 0) |
| goto out; |
| |
| nlink += ret; |
| |
| ret = 0; |
| |
| if (nlink != inode->i_nlink) { |
| set_nlink(inode, 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); |
| if (ret) |
| goto out; |
| } |
| ret = insert_orphan_item(trans, root, ino); |
| } |
| |
| out: |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| 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); |
| iput(inode); |
| if (ret) |
| goto out; |
| |
| /* |
| * 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; |
| key.type = BTRFS_ORPHAN_ITEM_KEY; |
| key.offset = objectid; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, &key, 0); |
| |
| btrfs_release_path(path); |
| if (ret == 0) { |
| if (!inode->i_nlink) |
| set_nlink(inode, 1); |
| else |
| inc_nlink(inode); |
| ret = btrfs_update_inode(trans, root, inode); |
| } else if (ret == -EEXIST) { |
| ret = 0; |
| } else { |
| BUG(); /* Logic Error */ |
| } |
| 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, |
| u64 dirid, u64 index, |
| char *name, int name_len, |
| 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, BTRFS_I(dir), BTRFS_I(inode), name, |
| name_len, 1, index); |
| |
| /* FIXME, put inode into FIXUP list */ |
| |
| iput(inode); |
| iput(dir); |
| return ret; |
| } |
| |
| /* |
| * Return true if an inode reference exists in the log for the given name, |
| * inode and parent inode. |
| */ |
| static bool name_in_log_ref(struct btrfs_root *log_root, |
| const char *name, const int name_len, |
| const u64 dirid, const u64 ino) |
| { |
| struct btrfs_key search_key; |
| |
| search_key.objectid = ino; |
| search_key.type = BTRFS_INODE_REF_KEY; |
| search_key.offset = dirid; |
| if (backref_in_log(log_root, &search_key, dirid, name, name_len)) |
| return true; |
| |
| search_key.type = BTRFS_INODE_EXTREF_KEY; |
| search_key.offset = btrfs_extref_hash(dirid, name, name_len); |
| if (backref_in_log(log_root, &search_key, dirid, name, name_len)) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * 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. |
| * |
| * Returns < 0 on error, 0 if the name wasn't replayed (dentry points to a |
| * non-existing inode) and 1 if the name was replayed. |
| */ |
| 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 = 0; |
| bool update_size = (key->type == BTRFS_DIR_INDEX_KEY); |
| bool name_added = false; |
| |
| 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) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| 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 { |
| /* Corruption */ |
| ret = -EINVAL; |
| goto out; |
| } |
| 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) { |
| update_size = false; |
| 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, BTRFS_I(dir), dst_di); |
| if (ret) |
| goto out; |
| |
| if (key->type == BTRFS_DIR_INDEX_KEY) |
| goto insert; |
| out: |
| btrfs_release_path(path); |
| if (!ret && update_size) { |
| btrfs_i_size_write(BTRFS_I(dir), dir->i_size + name_len * 2); |
| ret = btrfs_update_inode(trans, root, dir); |
| } |
| kfree(name); |
| iput(dir); |
| if (!ret && name_added) |
| ret = 1; |
| return ret; |
| |
| insert: |
| if (name_in_log_ref(root->log_root, name, name_len, |
| key->objectid, log_key.objectid)) { |
| /* The dentry will be added later. */ |
| ret = 0; |
| update_size = false; |
| goto out; |
| } |
| btrfs_release_path(path); |
| ret = insert_one_name(trans, root, key->objectid, key->offset, |
| name, name_len, &log_key); |
| if (ret && ret != -ENOENT && ret != -EEXIST) |
| goto out; |
| if (!ret) |
| name_added = true; |
| update_size = false; |
| ret = 0; |
| 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 = 0; |
| u32 item_size = btrfs_item_size_nr(eb, slot); |
| struct btrfs_dir_item *di; |
| int name_len; |
| unsigned long ptr; |
| unsigned long ptr_end; |
| struct btrfs_path *fixup_path = NULL; |
| |
| ptr = btrfs_item_ptr_offset(eb, slot); |
| ptr_end = ptr + item_size; |
| while (ptr < ptr_end) { |
| di = (struct btrfs_dir_item *)ptr; |
| name_len = btrfs_dir_name_len(eb, di); |
| ret = replay_one_name(trans, root, path, eb, di, key); |
| if (ret < 0) |
| break; |
| ptr = (unsigned long)(di + 1); |
| ptr += name_len; |
| |
| /* |
| * If this entry refers to a non-directory (directories can not |
| * have a link count > 1) and it was added in the transaction |
| * that was not committed, make sure we fixup the link count of |
| * the inode it the entry points to. Otherwise something like |
| * the following would result in a directory pointing to an |
| * inode with a wrong link that does not account for this dir |
| * entry: |
| * |
| * mkdir testdir |
| * touch testdir/foo |
| * touch testdir/bar |
| * sync |
| * |
| * ln testdir/bar testdir/bar_link |
| * ln testdir/foo testdir/foo_link |
| * xfs_io -c "fsync" testdir/bar |
| * |
| * <power failure> |
| * |
| * mount fs, log replay happens |
| * |
| * File foo would remain with a link count of 1 when it has two |
| * entries pointing to it in the directory testdir. This would |
| * make it impossible to ever delete the parent directory has |
| * it would result in stale dentries that can never be deleted. |
| */ |
| if (ret == 1 && btrfs_dir_type(eb, di) != BTRFS_FT_DIR) { |
| struct btrfs_key di_key; |
| |
| if (!fixup_path) { |
| fixup_path = btrfs_alloc_path(); |
| if (!fixup_path) { |
| ret = -ENOMEM; |
| break; |
| } |
| } |
| |
| btrfs_dir_item_key_to_cpu(eb, di, &di_key); |
| ret = link_to_fixup_dir(trans, root, fixup_path, |
| di_key.objectid); |
| if (ret) |
| break; |
| } |
| ret = 0; |
| } |
| btrfs_free_path(fixup_path); |
| return ret; |
| } |
| |
| /* |
| * 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]); |
| path->slots[0]++; |
| if (path->slots[0] >= nritems) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret) |
| goto out; |
| } |
| |
| 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; |
| 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 (!log_di || log_di == ERR_PTR(-ENOENT)) { |
| 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); |
| if (ret) { |
| kfree(name); |
| iput(inode); |
| goto out; |
| } |
| |
| inc_nlink(inode); |
| ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir), |
| BTRFS_I(inode), name, name_len); |
| if (!ret) |
| ret = btrfs_run_delayed_items(trans); |
| kfree(name); |
| iput(inode); |
| if (ret) |
| goto out; |
| |
| /* 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; |
| } else if (IS_ERR(log_di)) { |
| kfree(name); |
| return PTR_ERR(log_di); |
| } |
| 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; |
| } |
| |
| static int replay_xattr_deletes(struct btrfs_trans_handle *trans, |
| struct btrfs_root *root, |
| struct btrfs_root *log, |
| struct btrfs_path *path, |
| const u64 ino) |
| { |
| struct btrfs_key search_key; |
| struct btrfs_path *log_path; |
| int i; |
| int nritems; |
| int ret; |
| |
| log_path = btrfs_alloc_path(); |
| if (!log_path) |
| return -ENOMEM; |
| |
| search_key.objectid = ino; |
| search_key.type = BTRFS_XATTR_ITEM_KEY; |
| search_key.offset = 0; |
| again: |
| ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| process_leaf: |
| nritems = btrfs_header_nritems(path->nodes[0]); |
| for (i = path->slots[0]; i < nritems; i++) { |
| struct btrfs_key key; |
| struct btrfs_dir_item *di; |
| struct btrfs_dir_item *log_di; |
| u32 total_size; |
| u32 cur; |
| |
| btrfs_item_key_to_cpu(path->nodes[0], &key, i); |
| if (key.objectid != ino || key.type != BTRFS_XATTR_ITEM_KEY) { |
| ret = 0; |
| goto out; |
| } |
| |
| di = btrfs_item_ptr(path->nodes[0], i, struct btrfs_dir_item); |
| total_size = btrfs_item_size_nr(path->nodes[0], i); |
| cur = 0; |
| while (cur < total_size) { |
| u16 name_len = btrfs_dir_name_len(path->nodes[0], di); |
| u16 data_len = btrfs_dir_data_len(path->nodes[0], di); |
| u32 this_len = sizeof(*di) + name_len + data_len; |
| char *name; |
| |
| name = kmalloc(name_len, GFP_NOFS); |
| if (!name) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| read_extent_buffer(path->nodes[0], name, |
| (unsigned long)(di + 1), name_len); |
| |
| log_di = btrfs_lookup_xattr(NULL, log, log_path, ino, |
| name, name_len, 0); |
| btrfs_release_path(log_path); |
| if (!log_di) { |
| /* Doesn't exist in log tree, so delete it. */ |
| btrfs_release_path(path); |
| di = btrfs_lookup_xattr(trans, root, path, ino, |
| name, name_len, -1); |
| kfree(name); |
| if (IS_ERR(di)) { |
| ret = PTR_ERR(di); |
| goto out; |
| } |
| ASSERT(di); |
| ret = btrfs_delete_one_dir_name(trans, root, |
| path, di); |
| if (ret) |
| goto out; |
| btrfs_release_path(path); |
| search_key = key; |
| goto again; |
| } |
| kfree(name); |
| if (IS_ERR(log_di)) { |
| ret = PTR_ERR(log_di); |
| goto out; |
| } |
| cur += this_len; |
| di = (struct btrfs_dir_item *)((char *)di + this_len); |
| } |
| } |
| ret = btrfs_next_leaf(root, path); |
| if (ret > 0) |
| ret = 0; |
| else if (ret == 0) |
| goto process_leaf; |
| out: |
| btrfs_free_path(log_path); |
| btrfs_release_path(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 == 1) |
| break; |
| else if (ret < 0) |
| goto out; |
| } |
| 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); |
| if (ret) |
| goto out; |
| 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 level) |
| { |
| int nritems; |
| struct btrfs_path *path; |
| struct btrfs_root *root = wc->replay_dest; |
| struct btrfs_key key; |
| int i; |
| int ret; |
| |
| ret = btrfs_read_buffer(eb, gen, level, NULL); |
| if (ret) |
| return ret; |
| |
| 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); |
| /* |
| * If we have a tmpfile (O_TMPFILE) that got fsync'ed |
| * and never got linked before the fsync, skip it, as |
| * replaying it is pointless since it would be deleted |
| * later. We skip logging tmpfiles, but it's always |
| * possible we are replaying a log created with a kernel |
| * that used to log tmpfiles. |
| */ |
| if (btrfs_inode_nlink(eb, inode_item) == 0) { |
| wc->ignore_cur_inode = true; |
| continue; |
| } else { |
| wc->ignore_cur_inode = false; |
| } |
| ret = replay_xattr_deletes(wc->trans, root, log, |
| path, key.objectid); |
| if (ret) |
| break; |
| mode = btrfs_inode_mode(eb, inode_item); |
| if (S_ISDIR(mode)) { |
| ret = replay_dir_deletes(wc->trans, |
| root, log, path, key.objectid, 0); |
| if (ret) |
| break; |
| } |
| ret = overwrite_item(wc->trans, root, path, |
| eb, i, &key); |
| if (ret) |
| break; |
| |
| /* |
| * Before replaying extents, truncate the inode to its |
| * size. We need to do it now and not after log replay |
| * because before an fsync we can have prealloc extents |
| * added beyond the inode's i_size. If we did it after, |
| * through orphan cleanup for example, we would drop |
| * those prealloc extents just after replaying them. |
| */ |
| if (S_ISREG(mode)) { |
| struct inode *inode; |
| u64 from; |
| |
| inode = read_one_inode(root, key.objectid); |
| if (!inode) { |
| ret = -EIO; |
| break; |
| } |
| from = ALIGN(i_size_read(inode), |
| root->fs_info->sectorsize); |
| ret = btrfs_drop_extents(wc->trans, root, inode, |
| from, (u64)-1, 1); |
| if (!ret) { |
| /* Update the inode's nbytes. */ |
| ret = btrfs_update_inode(wc->trans, |
| root, inode); |
| } |
| iput(inode); |
| if (ret) |
| break; |
| } |
| |
| ret = link_to_fixup_dir(wc->trans, root, |
| path, key.objectid); |
| if (ret) |
| break; |
| } |
| |
| if (wc->ignore_cur_inode) |
| continue; |
| |
| if (key.type == BTRFS_DIR_INDEX_KEY && |
| wc->stage == LOG_WALK_REPLAY_DIR_INDEX) { |
| ret = replay_one_dir_item(wc->trans, root, path, |
| eb, i, &key); |
| if (ret) |
| break; |
| } |
| |
| 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); |
| if (ret) |
| break; |
| } else if (key.type == BTRFS_INODE_REF_KEY || |
| key.type == BTRFS_INODE_EXTREF_KEY) { |
| ret = add_inode_ref(wc->trans, root, log, path, |
| eb, i, &key); |
| if (ret && ret != -ENOENT) |
| break; |
| ret = 0; |
| } else if (key.type == BTRFS_EXTENT_DATA_KEY) { |
| ret = replay_one_extent(wc->trans, root, path, |
| eb, i, &key); |
| if (ret) |
| break; |
| } else if (key.type == BTRFS_DIR_ITEM_KEY) { |
| ret = replay_one_dir_item(wc->trans, root, path, |
| eb, i, &key); |
| if (ret) |
| break; |
| } |
| } |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| 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) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| 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) { |
| struct btrfs_key first_key; |
| |
| WARN_ON(*level < 0); |
| WARN_ON(*level >= BTRFS_MAX_LEVEL); |
| cur = path->nodes[*level]; |
| |
| WARN_ON(btrfs_header_level(cur) != *level); |
| |
| 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]); |
| btrfs_node_key_to_cpu(cur, &first_key, path->slots[*level]); |
| blocksize = fs_info->nodesize; |
| |
| parent = path->nodes[*level]; |
| root_owner = btrfs_header_owner(parent); |
| |
| next = btrfs_find_create_tree_block(fs_info, bytenr); |
| if (IS_ERR(next)) |
| return PTR_ERR(next); |
| |
| if (*level == 1) { |
| ret = wc->process_func(root, next, wc, ptr_gen, |
| *level - 1); |
| if (ret) { |
| free_extent_buffer(next); |
| return ret; |
| } |
| |
| path->slots[*level]++; |
| if (wc->free) { |
| ret = btrfs_read_buffer(next, ptr_gen, |
| *level - 1, &first_key); |
| if (ret) { |
| free_extent_buffer(next); |
| return ret; |
| } |
| |
| if (trans) { |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(fs_info, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| } else { |
| if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags)) |
| clear_extent_buffer_dirty(next); |
| } |
| |
| WARN_ON(root_owner != |
| BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_and_pin_reserved_extent( |
| fs_info, bytenr, |
| blocksize); |
| if (ret) { |
| free_extent_buffer(next); |
| return ret; |
| } |
| } |
| free_extent_buffer(next); |
| continue; |
| } |
| ret = btrfs_read_buffer(next, ptr_gen, *level - 1, &first_key); |
| if (ret) { |
| free_extent_buffer(next); |
| return ret; |
| } |
| |
| 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) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| 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]), |
| *level); |
| if (ret) |
| return ret; |
| |
| if (wc->free) { |
| struct extent_buffer *next; |
| |
| next = path->nodes[*level]; |
| |
| if (trans) { |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(fs_info, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| } else { |
| if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags)) |
| clear_extent_buffer_dirty(next); |
| } |
| |
| WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_and_pin_reserved_extent( |
| fs_info, |
| path->nodes[*level]->start, |
| path->nodes[*level]->len); |
| if (ret) |
| return 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) |
| { |
| struct btrfs_fs_info *fs_info = log->fs_info; |
| int ret = 0; |
| int wret; |
| int level; |
| struct btrfs_path *path; |
| 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; |
| goto out; |
| } |
| |
| wret = walk_up_log_tree(trans, log, path, &level, wc); |
| if (wret > 0) |
| break; |
| if (wret < 0) { |
| ret = wret; |
| goto out; |
| } |
| } |
| |
| /* was the root node processed? if not, catch it here */ |
| if (path->nodes[orig_level]) { |
| ret = wc->process_func(log, path->nodes[orig_level], wc, |
| btrfs_header_generation(path->nodes[orig_level]), |
| orig_level); |
| if (ret) |
| goto out; |
| if (wc->free) { |
| struct extent_buffer *next; |
| |
| next = path->nodes[orig_level]; |
| |
| if (trans) { |
| btrfs_tree_lock(next); |
| btrfs_set_lock_blocking(next); |
| clean_tree_block(fs_info, next); |
| btrfs_wait_tree_block_writeback(next); |
| btrfs_tree_unlock(next); |
| } else { |
| if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &next->bflags)) |
| clear_extent_buffer_dirty(next); |
| } |
| |
| WARN_ON(log->root_key.objectid != |
| BTRFS_TREE_LOG_OBJECTID); |
| ret = btrfs_free_and_pin_reserved_extent(fs_info, |
| next->start, next->len); |
| if (ret) |
| goto out; |
| } |
| } |
| |
| out: |
| 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, |
| struct btrfs_root_item *root_item) |
| { |
| struct btrfs_fs_info *fs_info = log->fs_info; |
| int ret; |
| |
| if (log->log_transid == 1) { |
| /* insert root item on the first sync */ |
| ret = btrfs_insert_root(trans, fs_info->log_root_tree, |
| &log->root_key, root_item); |
| } else { |
| ret = btrfs_update_root(trans, fs_info->log_root_tree, |
| &log->root_key, root_item); |
| } |
| return ret; |
| } |
| |
| static void wait_log_commit(struct btrfs_root *root, int 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 |
| */ |
| for (;;) { |
| prepare_to_wait(&root->log_commit_wait[index], |
| &wait, TASK_UNINTERRUPTIBLE); |
| |
| if (!(root->log_transid_committed < transid && |
| atomic_read(&root->log_commit[index]))) |
| break; |
| |
| mutex_unlock(&root->log_mutex); |
| schedule(); |
| mutex_lock(&root->log_mutex); |
| } |
| finish_wait(&root->log_commit_wait[index], &wait); |
| } |
| |
| static void wait_for_writer(struct btrfs_root *root) |
| { |
| DEFINE_WAIT(wait); |
| |
| for (;;) { |
| prepare_to_wait(&root->log_writer_wait, &wait, |
| TASK_UNINTERRUPTIBLE); |
| if (!atomic_read(&root->log_writers)) |
| break; |
| |
| mutex_unlock(&root->log_mutex); |
| schedule(); |
| mutex_lock(&root->log_mutex); |
| } |
| finish_wait(&root->log_writer_wait, &wait); |
| } |
| |
| static inline void btrfs_remove_log_ctx(struct btrfs_root *root, |
| struct btrfs_log_ctx *ctx) |
| { |
| if (!ctx) |
| return; |
| |
| mutex_lock(&root->log_mutex); |
| list_del_init(&ctx->list); |
| mutex_unlock(&root->log_mutex); |
| } |
| |
| /* |
| * Invoked in log mutex context, or be sure there is no other task which |
| * can access the list. |
| */ |
| static inline void btrfs_remove_all_log_ctxs(struct btrfs_root *root, |
| int index, int error) |
| { |
| struct btrfs_log_ctx *ctx; |
| struct btrfs_log_ctx *safe; |
| |
| list_for_each_entry_safe(ctx, safe, &root->log_ctxs[index], list) { |
| list_del_init(&ctx->list); |
| ctx->log_ret = error; |
| } |
| |
| INIT_LIST_HEAD(&root->log_ctxs[index]); |
| } |
| |
| /* |
| * 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, struct btrfs_log_ctx *ctx) |
| { |
| int index1; |
| int index2; |
| int mark; |
| int ret; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_root *log = root->log_root; |
| struct btrfs_root *log_root_tree = fs_info->log_root_tree; |
| struct btrfs_root_item new_root_item; |
| int log_transid = 0; |
| struct btrfs_log_ctx root_log_ctx; |
| struct blk_plug plug; |
| |
| mutex_lock(&root->log_mutex); |
| log_transid = ctx->log_transid; |
| if (root->log_transid_committed >= log_transid) { |
| mutex_unlock(&root->log_mutex); |
| return ctx->log_ret; |
| } |
| |
| index1 = log_transid % 2; |
| if (atomic_read(&root->log_commit[index1])) { |
| wait_log_commit(root, log_transid); |
| mutex_unlock(&root->log_mutex); |
| return ctx->log_ret; |
| } |
| ASSERT(log_transid == root->log_transid); |
| 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(root, log_transid - 1); |
| |
| while (1) { |
| int batch = atomic_read(&root->log_batch); |
| /* when we're on an ssd, just kick the log commit out */ |
| if (!btrfs_test_opt(fs_info, SSD) && |
| test_bit(BTRFS_ROOT_MULTI_LOG_TASKS, &root->state)) { |
| mutex_unlock(&root->log_mutex); |
| schedule_timeout_uninterruptible(1); |
| mutex_lock(&root->log_mutex); |
| } |
| wait_for_writer(root); |
| if (batch == atomic_read(&root->log_batch)) |
| break; |
| } |
| |
| /* bail out if we need to do a full commit */ |
| if (btrfs_need_log_full_commit(fs_info, trans)) { |
| ret = -EAGAIN; |
| mutex_unlock(&root->log_mutex); |
| goto out; |
| } |
| |
| 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. |
| */ |
| blk_start_plug(&plug); |
| ret = btrfs_write_marked_extents(fs_info, &log->dirty_log_pages, mark); |
| if (ret) { |
| blk_finish_plug(&plug); |
| btrfs_abort_transaction(trans, ret); |
| btrfs_set_log_full_commit(fs_info, trans); |
| mutex_unlock(&root->log_mutex); |
| goto out; |
| } |
| |
| /* |
| * We _must_ update under the root->log_mutex in order to make sure we |
| * have a consistent view of the log root we are trying to commit at |
| * this moment. |
| * |
| * We _must_ copy this into a local copy, because we are not holding the |
| * log_root_tree->log_mutex yet. This is important because when we |
| * commit the log_root_tree we must have a consistent view of the |
| * log_root_tree when we update the super block to point at the |
| * log_root_tree bytenr. If we update the log_root_tree here we'll race |
| * with the commit and possibly point at the new block which we may not |
| * have written out. |
| */ |
| btrfs_set_root_node(&log->root_item, log->node); |
| memcpy(&new_root_item, &log->root_item, sizeof(new_root_item)); |
| |
| root->log_transid++; |
| log->log_transid = root->log_transid; |
| root->log_start_pid = 0; |
| /* |
| * 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); |
| |
| btrfs_init_log_ctx(&root_log_ctx, NULL); |
| |
| mutex_lock(&log_root_tree->log_mutex); |
| atomic_inc(&log_root_tree->log_batch); |
| atomic_inc(&log_root_tree->log_writers); |
| |
| index2 = log_root_tree->log_transid % 2; |
| list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]); |
| root_log_ctx.log_transid = log_root_tree->log_transid; |
| |
| mutex_unlock(&log_root_tree->log_mutex); |
| |
| mutex_lock(&log_root_tree->log_mutex); |
| |
| /* |
| * Now we are safe to update the log_root_tree because we're under the |
| * log_mutex, and we're a current writer so we're holding the commit |
| * open until we drop the log_mutex. |
| */ |
| ret = update_log_root(trans, log, &new_root_item); |
| |
| if (atomic_dec_and_test(&log_root_tree->log_writers)) { |
| /* atomic_dec_and_test implies a barrier */ |
| cond_wake_up_nomb(&log_root_tree->log_writer_wait); |
| } |
| |
| if (ret) { |
| if (!list_empty(&root_log_ctx.list)) |
| list_del_init(&root_log_ctx.list); |
| |
| blk_finish_plug(&plug); |
| btrfs_set_log_full_commit(fs_info, trans); |
| |
| if (ret != -ENOSPC) { |
| btrfs_abort_transaction(trans, ret); |
| mutex_unlock(&log_root_tree->log_mutex); |
| goto out; |
| } |
| btrfs_wait_tree_log_extents(log, mark); |
| mutex_unlock(&log_root_tree->log_mutex); |
| ret = -EAGAIN; |
| goto out; |
| } |
| |
| if (log_root_tree->log_transid_committed >= root_log_ctx.log_transid) { |
| blk_finish_plug(&plug); |
| list_del_init(&root_log_ctx.list); |
| mutex_unlock(&log_root_tree->log_mutex); |
| ret = root_log_ctx.log_ret; |
| goto out; |
| } |
| |
| index2 = root_log_ctx.log_transid % 2; |
| if (atomic_read(&log_root_tree->log_commit[index2])) { |
| blk_finish_plug(&plug); |
| ret = btrfs_wait_tree_log_extents(log, mark); |
| wait_log_commit(log_root_tree, |
| root_log_ctx.log_transid); |
| mutex_unlock(&log_root_tree->log_mutex); |
| if (!ret) |
| ret = root_log_ctx.log_ret; |
| goto out; |
| } |
| ASSERT(root_log_ctx.log_transid == log_root_tree->log_transid); |
| atomic_set(&log_root_tree->log_commit[index2], 1); |
| |
| if (atomic_read(&log_root_tree->log_commit |