Liu Bo
2012-Aug-16 06:10 UTC
[PATCH v2 1/2] 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: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- fs/btrfs/backref.c | 24 ++++++++++++++++-------- fs/btrfs/backref.h | 3 ++- fs/btrfs/ioctl.c | 6 ++++-- fs/btrfs/scrub.c | 14 ++++++++------ fs/btrfs/send.c | 7 ++++--- 5 files changed, 34 insertions(+), 20 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index a256f3b..08d5385 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -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); - if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) - return BTRFS_EXTENT_FLAG_TREE_BLOCK; - if (flags & BTRFS_EXTENT_FLAG_DATA) - return BTRFS_EXTENT_FLAG_DATA; + + WARN_ON(!flags_ret); + if (flags_ret) { + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) + *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; } @@ -1432,13 +1440,13 @@ 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 & BTRFS_EXTENT_FLAG_TREE_BLOCK) + if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) ret = -EINVAL; if (ret < 0) return ret; diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index 032f4dc..4fda5d8 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -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, diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 7bb7556..405b279 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -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; diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index b223620..5def223 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -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); diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index fb5ffe9..7186ae8 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -1143,6 +1143,7 @@ static int find_extent_clone(struct send_ctx *sctx, u64 logical; 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; @@ -1181,13 +1182,13 @@ static int find_extent_clone(struct send_ctx *sctx, } logical += btrfs_file_extent_offset(eb, fi); - ret = extent_from_logical(sctx->send_root->fs_info, - logical, tmp_path, &found_key); + ret = extent_from_logical(sctx->send_root->fs_info, logical, 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; } -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
We already have a helper, iterate_inodes_from_logical(), for logical resolve, so just use it. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- v1->v2: patch -EINVAL to -ENOENT to keep the behaviour, thanks to Jan. fs/btrfs/ioctl.c | 19 +++---------------- 1 files changed, 3 insertions(+), 16 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 405b279..be51870 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3210,12 +3210,9 @@ 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; - struct btrfs_key key; if (!capable(CAP_SYS_ADMIN)) return -EPERM; @@ -3241,23 +3238,13 @@ static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root, goto out; } - ret = extent_from_logical(root->fs_info, loi->logical, path, &key, - &flags); - btrfs_release_path(path); - - if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) + ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path, + build_ino_list, inodes); + if (ret == -EINVAL) ret = -ENOENT; if (ret < 0) goto out; - extent_item_pos = loi->logical - key.objectid; - ret = iterate_extent_inodes(root->fs_info, key.objectid, - extent_item_pos, 0, build_ino_list, - inodes); - - if (ret < 0) - goto out; - ret = copy_to_user((void *)(unsigned long)loi->inodes, (void *)(unsigned long)inodes, size); if (ret) -- 1.7.7.6 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html