From 951e05a90469e29326715e7e3aefd4680748b4fa Mon Sep 17 00:00:00 2001 From: Nikolay Borisov Date: Tue, 8 Jan 2019 16:53:46 +0200 Subject: [PATCH] btrfs: Remove impossible condition from mergable_maps We can never have extents marked as EXTENT_MAP_DELALLOC since this value is only ever used by btrfs_get_extent_fiemap. In this case the extent map is created by btrfs_get_extent_fiemap and is never really published, this flag is used to return the corresponding userspace one. Considering this, it's pointless having a check for EXTENT_MAP_DELALLOC in mergable_maps. Just remove it. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/extent_map.c | 5 +++-- fs/btrfs/extent_map.h | 1 + 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index a042a193c120..928f729c55ba 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -210,6 +210,9 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next) if (!list_empty(&prev->list) || !list_empty(&next->list)) return 0; + ASSERT(next->block_start != EXTENT_MAP_DELALLOC && + prev->block_start != EXTENT_MAP_DELALLOC); + if (extent_map_end(prev) == next->start && prev->flags == next->flags && prev->bdev == next->bdev && @@ -217,8 +220,6 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next) prev->block_start == EXTENT_MAP_HOLE) || (next->block_start == EXTENT_MAP_INLINE && prev->block_start == EXTENT_MAP_INLINE) || - (next->block_start == EXTENT_MAP_DELALLOC && - prev->block_start == EXTENT_MAP_DELALLOC) || (next->block_start < EXTENT_MAP_LAST_BYTE - 1 && next->block_start == extent_map_block_end(prev)))) { return 1; diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h index ef05a0121652..473f039fcd7c 100644 --- a/fs/btrfs/extent_map.h +++ b/fs/btrfs/extent_map.h @@ -9,6 +9,7 @@ #define EXTENT_MAP_LAST_BYTE ((u64)-4) #define EXTENT_MAP_HOLE ((u64)-3) #define EXTENT_MAP_INLINE ((u64)-2) +/* used only during fiemap calls */ #define EXTENT_MAP_DELALLOC ((u64)-1) /* bits for the extent_map::flags field */