Btrfs already skip store of data where compression didn't free at least one byte. So make logic better and make check that compression free at least one PAGE_SIZE, because in another case it useless to store this data compressed
Signed-off-by: Timofey Titovets <[email protected]> --- fs/btrfs/lzo.c | 5 ++++- fs/btrfs/zlib.c | 3 ++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c index bd0b0938..7f38bc3c 100644 --- a/fs/btrfs/lzo.c +++ b/fs/btrfs/lzo.c @@ -229,8 +229,11 @@ static int lzo_compress_pages(struct list_head *ws, in_len = min(bytes_left, PAGE_SIZE); } - if (tot_out > tot_in) + /* Compression must save at least one PAGE_SIZE */ + if (tot_out + PAGE_SIZE => tot_in) { + ret = -E2BIG; goto out; + } /* store the size of all chunks of compressed data */ cpage_out = kmap(pages[0]); diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c index 135b1082..2b04259b 100644 --- a/fs/btrfs/zlib.c +++ b/fs/btrfs/zlib.c @@ -191,7 +191,8 @@ static int zlib_compress_pages(struct list_head *ws, goto out; } - if (workspace->strm.total_out >= workspace->strm.total_in) { + /* Compression must save at least one PAGE_SIZE */ + if (workspace->strm.total_out + PAGE_SIZE >= workspace->strm.total_in) { ret = -E2BIG; goto out; } -- 2.13.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
