diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2013-10-01 20:11:26 (GMT) |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2013-10-25 03:35:00 (GMT) |
commit | 474279dc0f7745124fc76b474c8dc1294f8e87ce (patch) | |
tree | 2ad5e963e698e9524e0eabe466534f03ce324226 /fs | |
parent | 7eb5e8826911f2792179f99e77e75fbb7ef53a4a (diff) | |
download | linux-474279dc0f7745124fc76b474c8dc1294f8e87ce.tar.xz |
split __lookup_mnt() in two functions
Instead of passing the direction as argument (and checking it on every
step through the hash chain), just have separate __lookup_mnt() and
__lookup_mnt_last(). And use the standard iterators...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/mount.h | 3 | ||||
-rw-r--r-- | fs/namei.c | 4 | ||||
-rw-r--r-- | fs/namespace.c | 42 | ||||
-rw-r--r-- | fs/pnode.c | 6 |
4 files changed, 30 insertions, 25 deletions
@@ -77,7 +77,8 @@ static inline int is_mounted(struct vfsmount *mnt) return !IS_ERR_OR_NULL(real_mount(mnt)); } -extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int); +extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *); +extern struct mount *__lookup_mnt_last(struct vfsmount *, struct dentry *); static inline void get_mnt_ns(struct mnt_namespace *ns) { @@ -1111,7 +1111,7 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path, if (!d_mountpoint(path->dentry)) break; - mounted = __lookup_mnt(path->mnt, path->dentry, 1); + mounted = __lookup_mnt(path->mnt, path->dentry); if (!mounted) break; path->mnt = &mounted->mnt; @@ -1132,7 +1132,7 @@ static void follow_mount_rcu(struct nameidata *nd) { while (d_mountpoint(nd->path.dentry)) { struct mount *mounted; - mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry, 1); + mounted = __lookup_mnt(nd->path.mnt, nd->path.dentry); if (!mounted) break; nd->path.mnt = &mounted->mnt; diff --git a/fs/namespace.c b/fs/namespace.c index 5cbe8ce..500202c 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -548,29 +548,33 @@ static void free_vfsmnt(struct mount *mnt) } /* - * find the first or last mount at @dentry on vfsmount @mnt depending on - * @dir. If @dir is set return the first mount else return the last mount. + * find the first mount at @dentry on vfsmount @mnt. * vfsmount_lock must be held for read or write. */ -struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry, - int dir) +struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry) { struct list_head *head = mount_hashtable + hash(mnt, dentry); - struct list_head *tmp = head; - struct mount *p, *found = NULL; + struct mount *p; - for (;;) { - tmp = dir ? tmp->next : tmp->prev; - p = NULL; - if (tmp == head) - break; - p = list_entry(tmp, struct mount, mnt_hash); - if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry) { - found = p; - break; - } - } - return found; + list_for_each_entry(p, head, mnt_hash) + if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry) + return p; + return NULL; +} + +/* + * find the last mount at @dentry on vfsmount @mnt. + * vfsmount_lock must be held for read or write. + */ +struct mount *__lookup_mnt_last(struct vfsmount *mnt, struct dentry *dentry) +{ + struct list_head *head = mount_hashtable + hash(mnt, dentry); + struct mount *p; + + list_for_each_entry_reverse(p, head, mnt_hash) + if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry) + return p; + return NULL; } /* @@ -594,7 +598,7 @@ struct vfsmount *lookup_mnt(struct path *path) struct mount *child_mnt; br_read_lock(&vfsmount_lock); - child_mnt = __lookup_mnt(path->mnt, path->dentry, 1); + child_mnt = __lookup_mnt(path->mnt, path->dentry); if (child_mnt) { mnt_add_count(child_mnt, 1); br_read_unlock(&vfsmount_lock); @@ -310,7 +310,7 @@ int propagate_mount_busy(struct mount *mnt, int refcnt) for (m = propagation_next(parent, parent); m; m = propagation_next(m, parent)) { - child = __lookup_mnt(&m->mnt, mnt->mnt_mountpoint, 0); + child = __lookup_mnt_last(&m->mnt, mnt->mnt_mountpoint); if (child && list_empty(&child->mnt_mounts) && (ret = do_refcount_check(child, 1))) break; @@ -332,8 +332,8 @@ static void __propagate_umount(struct mount *mnt) for (m = propagation_next(parent, parent); m; m = propagation_next(m, parent)) { - struct mount *child = __lookup_mnt(&m->mnt, - mnt->mnt_mountpoint, 0); + struct mount *child = __lookup_mnt_last(&m->mnt, + mnt->mnt_mountpoint); /* * umount the child only if the child has no * other children |