From 71a635516ca521931be418827150f782b0a03ae7 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Mon, 6 Nov 2017 19:23:00 +0100 Subject: [PATCH] btrfs: switch to on-stack csum buffer in csum_tree_block The maximum size of a checksum buffer is known, BTRFS_CSUM_SIZE, and we don't have to allocate it dynamically. This code path is not used at all as we have only the crc32c and use an on-stack buffer already. Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index cbf37df05a88..5f9430063c50 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -285,7 +285,7 @@ static int csum_tree_block(struct btrfs_fs_info *fs_info, int verify) { u16 csum_size = btrfs_super_csum_size(fs_info->super_copy); - char *result = NULL; + char result[BTRFS_CSUM_SIZE]; unsigned long len; unsigned long cur_len; unsigned long offset = BTRFS_CSUM_SIZE; @@ -294,7 +294,6 @@ static int csum_tree_block(struct btrfs_fs_info *fs_info, unsigned long map_len; int err; u32 crc = ~(u32)0; - unsigned long inline_result; len = buf->len - offset; while (len > 0) { @@ -308,13 +307,7 @@ static int csum_tree_block(struct btrfs_fs_info *fs_info, len -= cur_len; offset += cur_len; } - if (csum_size > sizeof(inline_result)) { - result = kzalloc(csum_size, GFP_NOFS); - if (!result) - return -ENOMEM; - } else { - result = (char *)&inline_result; - } + memset(result, 0, BTRFS_CSUM_SIZE); btrfs_csum_final(crc, result); @@ -329,15 +322,12 @@ static int csum_tree_block(struct btrfs_fs_info *fs_info, "%s checksum verify failed on %llu wanted %X found %X level %d", fs_info->sb->s_id, buf->start, val, found, btrfs_header_level(buf)); - if (result != (char *)&inline_result) - kfree(result); return -EUCLEAN; } } else { write_extent_buffer(buf, result, 0, csum_size); } - if (result != (char *)&inline_result) - kfree(result); + return 0; } -- 2.45.2