Currently kernfs_link_sibling() increates parent->dir.subdirs before adding the node into parent's chidren rb tree.
Because it is possible that kernfs_link_sibling() couldn't find a suitable slot and bail out, this leads to a mismatch between elevated subdir count with actual children node numbers. This patches fix this problem, by moving the subdir accouting after the actual addtion happening. Signed-off-by: Jianyu Zhan <[email protected]> --- fs/kernfs/dir.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 78f3403..ac127cd 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -232,9 +232,6 @@ static int kernfs_link_sibling(struct kernfs_node *kn) struct rb_node **node = &kn->parent->dir.children.rb_node; struct rb_node *parent = NULL; - if (kernfs_type(kn) == KERNFS_DIR) - kn->parent->dir.subdirs++; - while (*node) { struct kernfs_node *pos; int result; @@ -249,9 +246,15 @@ static int kernfs_link_sibling(struct kernfs_node *kn) else return -EEXIST; } + /* add new node and rebalance the tree */ rb_link_node(&kn->rb, parent, node); rb_insert_color(&kn->rb, &kn->parent->dir.children); + + /* successfully added, account subdir number */ + if (kernfs_type(kn) == KERNFS_DIR) + kn->parent->dir.subdirs++; + return 0; } -- 1.9.0.GIT -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
