From 67710892ec983aa79ad1e2a2642fe8e3a4a194ea Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Mon, 6 Jun 2016 11:51:25 +0100 Subject: [PATCH] Btrfs: be more precise on errors when getting an inode from disk When we attempt to read an inode from disk, we end up always returning an -ESTALE error to the caller regardless of the actual failure reason, which can be an out of memory problem (when allocating a path), some error found when reading from the fs/subvolume btree (like a genuine IO error) or the inode does not exists. So lets start returning the real error code to the callers so that they don't treat all -ESTALE errors as meaning that the inode does not exists (such as during orphan cleanup). This will also be needed for a subsequent patch in the same series dealing with a special fsync case. Signed-off-by: Filipe Manana --- fs/btrfs/inode.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 3e61bd1f3f65..f9686541997b 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3428,10 +3428,10 @@ int btrfs_orphan_cleanup(struct btrfs_root *root) found_key.offset = 0; inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL); ret = PTR_ERR_OR_ZERO(inode); - if (ret && ret != -ESTALE) + if (ret && ret != -ENOENT) goto out; - if (ret == -ESTALE && root == root->fs_info->tree_root) { + if (ret == -ENOENT && root == root->fs_info->tree_root) { struct btrfs_root *dead_root; struct btrfs_fs_info *fs_info = root->fs_info; int is_dead_root = 0; @@ -3467,7 +3467,7 @@ int btrfs_orphan_cleanup(struct btrfs_root *root) * Inode is already gone but the orphan item is still there, * kill the orphan item. */ - if (ret == -ESTALE) { + if (ret == -ENOENT) { trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); @@ -3626,7 +3626,7 @@ static noinline int acls_after_inode_item(struct extent_buffer *leaf, /* * read an inode from the btree into the in-memory inode */ -static void btrfs_read_locked_inode(struct inode *inode) +static int btrfs_read_locked_inode(struct inode *inode) { struct btrfs_path *path; struct extent_buffer *leaf; @@ -3645,14 +3645,19 @@ static void btrfs_read_locked_inode(struct inode *inode) filled = true; path = btrfs_alloc_path(); - if (!path) + if (!path) { + ret = -ENOMEM; goto make_bad; + } memcpy(&location, &BTRFS_I(inode)->location, sizeof(location)); ret = btrfs_lookup_inode(NULL, root, path, &location, 0); - if (ret) + if (ret) { + if (ret > 0) + ret = -ENOENT; goto make_bad; + } leaf = path->nodes[0]; @@ -3805,11 +3810,12 @@ cache_acl: } btrfs_update_iflags(inode); - return; + return 0; make_bad: btrfs_free_path(path); make_bad_inode(inode); + return ret; } /* @@ -5595,7 +5601,9 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, return ERR_PTR(-ENOMEM); if (inode->i_state & I_NEW) { - btrfs_read_locked_inode(inode); + int ret; + + ret = btrfs_read_locked_inode(inode); if (!is_bad_inode(inode)) { inode_tree_add(inode); unlock_new_inode(inode); @@ -5604,7 +5612,8 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location, } else { unlock_new_inode(inode); iput(inode); - inode = ERR_PTR(-ESTALE); + ASSERT(ret < 0); + inode = ERR_PTR(ret < 0 ? ret : -ESTALE); } } -- 2.20.1