diff options
Diffstat (limited to 'fs/dcache.c')
| -rw-r--r-- | fs/dcache.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 4365998..74da947 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2191,6 +2191,30 @@ int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry) return result; } +int path_is_under(struct path *path1, struct path *path2) +{ + struct vfsmount *mnt = path1->mnt; + struct dentry *dentry = path1->dentry; + int res; + spin_lock(&vfsmount_lock); + if (mnt != path2->mnt) { + for (;;) { + if (mnt->mnt_parent == mnt) { + spin_unlock(&vfsmount_lock); + return 0; + } + if (mnt->mnt_parent == path2->mnt) + break; + mnt = mnt->mnt_parent; + } + dentry = mnt->mnt_mountpoint; + } + res = is_subdir(dentry, path2->dentry); + spin_unlock(&vfsmount_lock); + return res; +} +EXPORT_SYMBOL(path_is_under); + void d_genocide(struct dentry *root) { struct dentry *this_parent = root; |