btrfs: switch to on-stack csum buffer in csum_tree_block (71a63551) · Commits · 戴 / test

fs/btrfs/disk-io.c

+3 −13

Original line number	Diff line number	Diff line
		@@ -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;
		}