Btrfs: check file extent type before anything else (007d31f7) · Commits · 戴 / test

I hit this problem with my no holes patch and it made me realize what the problem was for bz 60834. If the first item in the leaf is an inline extent and we try to read anything starting from disk_bytenr onward we will read off the end of the leaf. So we need to check to see what it's type is, and if it's not REG we can just break out. This should fix this problem. Thanks, Signed-off-by:

Josef Bacik <jbacik@fusionio.com> Signed-off-by:

Chris Mason <chris.mason@fusionio.com>

fs/btrfs/send.c

+5 −5

Original line number	Diff line number	Diff line
		@@ -3902,16 +3902,16 @@ static int is_extent_unchanged(struct send_ctx *sctx,
		while (key.offset < ekey->offset + left_len) {
		ei = btrfs_item_ptr(eb, slot, struct btrfs_file_extent_item);
		right_type = btrfs_file_extent_type(eb, ei);
		right_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
		right_len = btrfs_file_extent_num_bytes(eb, ei);
		right_offset = btrfs_file_extent_offset(eb, ei);
		right_gen = btrfs_file_extent_generation(eb, ei);

		if (right_type != BTRFS_FILE_EXTENT_REG) {
		ret = 0;
		goto out;
		}

		right_disknr = btrfs_file_extent_disk_bytenr(eb, ei);
		right_len = btrfs_file_extent_num_bytes(eb, ei);
		right_offset = btrfs_file_extent_offset(eb, ei);
		right_gen = btrfs_file_extent_generation(eb, ei);

		/*
		* Are we at extent 8? If yes, we know the extent is changed.
		* This may only happen on the first iteration.

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