Commit 69917e43 authored by Liu Bo's avatar Liu Bo Committed by Chris Mason
Browse files

Btrfs: fix a bug in parsing return value in logical resolve 



In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag.

It is possible to lose our errors because
(-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true.

I'm not sure if it is on purpose, it just looks too hacky if it is.
I'd rather use a real flag and a 'ret' to catch errors.

Acked-by: default avatarJan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: default avatarLiu Bo <liub.liubo@gmail.com>
parent dea7d76e

fs/btrfs/backref.c

+16 −8
Original line number Diff line number Diff line
@@ -1193,7 +1193,8 @@ char *btrfs_iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, 
 * tree blocks and <0 on error.

 */

int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,

			struct btrfs_path *path, struct btrfs_key *found_key)

			struct btrfs_path *path, struct btrfs_key *found_key,

			u64 *flags_ret)

{

	int ret;

	u64 flags;
@@ -1237,10 +1238,17 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical, 
		 (unsigned long long)found_key->objectid,

		 (unsigned long long)found_key->offset,

		 (unsigned long long)flags, item_size);



	WARN_ON(!flags_ret);

	if (flags_ret) {

		if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)

		return BTRFS_EXTENT_FLAG_TREE_BLOCK;

	if (flags & BTRFS_EXTENT_FLAG_DATA)

		return BTRFS_EXTENT_FLAG_DATA;

			*flags_ret = BTRFS_EXTENT_FLAG_TREE_BLOCK;

		else if (flags & BTRFS_EXTENT_FLAG_DATA)

			*flags_ret = BTRFS_EXTENT_FLAG_DATA;

		else

			BUG_ON(1);

		return 0;

	}



	return -EIO;

}
@@ -1433,15 +1441,15 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, 
{

	int ret;

	u64 extent_item_pos;

	u64 flags = 0;

	struct btrfs_key found_key;

	int search_commit_root = path->search_commit_root;



	ret = extent_from_logical(fs_info, logical, path,

					&found_key);

	ret = extent_from_logical(fs_info, logical, path, &found_key, &flags);

	btrfs_release_path(path);

	if (ret < 0)

		return ret;

	if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)

	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)

		return -EINVAL;



	extent_item_pos = logical - found_key.objectid;

fs/btrfs/backref.h

+2 −1
Original line number Diff line number Diff line
@@ -40,7 +40,8 @@ int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root, 
			struct btrfs_path *path);



int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,

			struct btrfs_path *path, struct btrfs_key *found_key);

			struct btrfs_path *path, struct btrfs_key *found_key,

			u64 *flags);



int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb,

				struct btrfs_extent_item *ei, u32 item_size,

fs/btrfs/ioctl.c

+4 −2
Original line number Diff line number Diff line
@@ -3211,6 +3211,7 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 
	int ret = 0;

	int size;

	u64 extent_item_pos;

	u64 flags = 0;

	struct btrfs_ioctl_logical_ino_args *loi;

	struct btrfs_data_container *inodes = NULL;

	struct btrfs_path *path = NULL;
@@ -3240,10 +3241,11 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, 
		goto out;

	}



	ret = extent_from_logical(root->fs_info, loi->logical, path, &key);

	ret = extent_from_logical(root->fs_info, loi->logical, path, &key,

				  &flags);

	btrfs_release_path(path);



	if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)

	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)

		ret = -ENOENT;

	if (ret < 0)

		goto out;

fs/btrfs/scrub.c

+8 −6
Original line number Diff line number Diff line
@@ -352,13 +352,14 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock) 
	struct extent_buffer *eb;

	struct btrfs_extent_item *ei;

	struct scrub_warning swarn;

	u32 item_size;

	int ret;

	unsigned long ptr = 0;

	u64 extent_item_pos;

	u64 flags = 0;

	u64 ref_root;

	u32 item_size;

	u8 ref_level;

	unsigned long ptr = 0;

	const int bufsize = 4096;

	u64 extent_item_pos;

	int ret;



	path = btrfs_alloc_path();
@@ -375,7 +376,8 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock) 
	if (!path || !swarn.scratch_buf || !swarn.msg_buf)

		goto out;



	ret = extent_from_logical(fs_info, swarn.logical, path, &found_key);

	ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,

				  &flags);

	if (ret < 0)

		goto out;
@@ -387,7 +389,7 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock) 
	item_size = btrfs_item_size_nr(eb, path->slots[0]);

	btrfs_release_path(path);



	if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {

	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {

		do {

			ret = tree_backref_for_extent(&ptr, eb, ei, item_size,

							&ref_root, &ref_level);

fs/btrfs/send.c

+4 −3
Original line number Diff line number Diff line
@@ -1152,6 +1152,7 @@ static int find_extent_clone(struct send_ctx *sctx, 
	u64 disk_byte;

	u64 num_bytes;

	u64 extent_item_pos;

	u64 flags = 0;

	struct btrfs_file_extent_item *fi;

	struct extent_buffer *eb = path->nodes[0];

	struct backref_ctx *backref_ctx = NULL;
@@ -1198,13 +1199,13 @@ static int find_extent_clone(struct send_ctx *sctx, 
	}

	logical = disk_byte + btrfs_file_extent_offset(eb, fi);



	ret = extent_from_logical(sctx->send_root->fs_info,

			disk_byte, tmp_path, &found_key);

	ret = extent_from_logical(sctx->send_root->fs_info, disk_byte, tmp_path,

				  &found_key, &flags);

	btrfs_release_path(tmp_path);



	if (ret < 0)

		goto out;

	if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {

	if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {

		ret = -EIO;

		goto out;

	}

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