From: Filipe Manana fdmanana@suse.com
[ Upstream commit 528ee697126fddaff448897c2d649bd756153c79 ]
At btrfs_set_inode_index_count() we refer twice to the number 2 as the initial index value for a directory (when it's empty), with a proper comment explaining the reason for that value. In the next patch I'll have to use that magic value in the directory logging code, so put the value in a #define at btrfs_inode.h, to avoid hardcoding the magic value again at tree-log.c.
Signed-off-by: Filipe Manana fdmanana@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/btrfs_inode.h | 12 ++++++++++-- fs/btrfs/inode.c | 10 ++-------- 2 files changed, 12 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 76ee1452c57ba..37ceea85b871c 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -13,6 +13,13 @@ #include "ordered-data.h" #include "delayed-inode.h"
+/* + * Since we search a directory based on f_pos (struct dir_context::pos) we have + * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so + * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()). + */ +#define BTRFS_DIR_START_INDEX 2 + /* * ordered_data_close is set by truncate when a file that used * to have good data has been truncated to zero. When it is set @@ -164,8 +171,9 @@ struct btrfs_inode { u64 disk_i_size;
/* - * if this is a directory then index_cnt is the counter for the index - * number for new files that are created + * If this is a directory then index_cnt is the counter for the index + * number for new files that are created. For an empty directory, this + * must be initialized to BTRFS_DIR_START_INDEX. */ u64 index_cnt;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index ac6ba984973c0..26a4acb856a38 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -6396,14 +6396,8 @@ static int btrfs_set_inode_index_count(struct btrfs_inode *inode) goto out; ret = 0;
- /* - * MAGIC NUMBER EXPLANATION: - * since we search a directory based on f_pos we have to start at 2 - * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody - * else has to start at 2 - */ if (path->slots[0] == 0) { - inode->index_cnt = 2; + inode->index_cnt = BTRFS_DIR_START_INDEX; goto out; }
@@ -6414,7 +6408,7 @@ static int btrfs_set_inode_index_count(struct btrfs_inode *inode)
if (found_key.objectid != btrfs_ino(inode) || found_key.type != BTRFS_DIR_INDEX_KEY) { - inode->index_cnt = 2; + inode->index_cnt = BTRFS_DIR_START_INDEX; goto out; }