diff options
| -rw-r--r-- | fs/fs_pin.c | 1 | ||||
| -rw-r--r-- | fs/mount.h | 4 | ||||
| -rw-r--r-- | fs/namespace.c | 44 |
3 files changed, 20 insertions, 29 deletions
diff --git a/fs/fs_pin.c b/fs/fs_pin.c index 0c77bdc238b..b06c98796af 100644 --- a/fs/fs_pin.c +++ b/fs/fs_pin.c @@ -1,7 +1,6 @@ #include <linux/fs.h> #include <linux/sched.h> #include <linux/slab.h> -#include <linux/fs_pin.h> #include "internal.h" #include "mount.h" diff --git a/fs/mount.h b/fs/mount.h index 0ad6f760ce5..6a61c2b3e38 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -2,6 +2,7 @@ #include <linux/seq_file.h> #include <linux/poll.h> #include <linux/ns_common.h> +#include <linux/fs_pin.h> struct mnt_namespace { atomic_t count; @@ -62,7 +63,8 @@ struct mount { int mnt_group_id; /* peer group identifier */ int mnt_expiry_mark; /* true if marked for expiry */ struct hlist_head mnt_pins; - struct path mnt_ex_mountpoint; + struct fs_pin mnt_umount; + struct dentry *mnt_ex_mountpoint; }; #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ diff --git a/fs/namespace.c b/fs/namespace.c index cd1e9681a0c..4a985ff0ddf 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -190,6 +190,14 @@ unsigned int mnt_get_count(struct mount *mnt) #endif } +static void drop_mountpoint(struct fs_pin *p) +{ + struct mount *m = container_of(p, struct mount, mnt_umount); + dput(m->mnt_ex_mountpoint); + pin_remove(p); + mntput(&m->mnt); +} + static struct mount *alloc_vfsmnt(const char *name) { struct mount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL); @@ -229,6 +237,7 @@ static struct mount *alloc_vfsmnt(const char *name) #ifdef CONFIG_FSNOTIFY INIT_HLIST_HEAD(&mnt->mnt_fsnotify_marks); #endif + init_fs_pin(&mnt->mnt_umount, drop_mountpoint); } return mnt; @@ -1289,7 +1298,6 @@ static HLIST_HEAD(unmounted); /* protected by namespace_sem */ static void namespace_unlock(void) { - struct mount *mnt; struct hlist_head head = unmounted; if (likely(hlist_empty(&head))) { @@ -1299,23 +1307,11 @@ static void namespace_unlock(void) head.first->pprev = &head.first; INIT_HLIST_HEAD(&unmounted); - - /* undo decrements we'd done in umount_tree() */ - hlist_for_each_entry(mnt, &head, mnt_hash) - if (mnt->mnt_ex_mountpoint.mnt) - mntget(mnt->mnt_ex_mountpoint.mnt); - up_write(&namespace_sem); synchronize_rcu(); - while (!hlist_empty(&head)) { - mnt = hlist_entry(head.first, struct mount, mnt_hash); - hlist_del_init(&mnt->mnt_hash); - if (mnt->mnt_ex_mountpoint.mnt) - path_put(&mnt->mnt_ex_mountpoint); - mntput(&mnt->mnt); - } + group_pin_kill(&head); } static inline void namespace_lock(void) @@ -1334,7 +1330,6 @@ void umount_tree(struct mount *mnt, int how) { HLIST_HEAD(tmp_list); struct mount *p; - struct mount *last = NULL; for (p = mnt; p; p = next_mnt(p, mnt)) { hlist_del_init_rcu(&p->mnt_hash); @@ -1347,33 +1342,28 @@ void umount_tree(struct mount *mnt, int how) if (how) propagate_umount(&tmp_list); - hlist_for_each_entry(p, &tmp_list, mnt_hash) { + while (!hlist_empty(&tmp_list)) { + p = hlist_entry(tmp_list.first, struct mount, mnt_hash); + hlist_del_init_rcu(&p->mnt_hash); list_del_init(&p->mnt_expire); list_del_init(&p->mnt_list); __touch_mnt_namespace(p->mnt_ns); p->mnt_ns = NULL; if (how < 2) p->mnt.mnt_flags |= MNT_SYNC_UMOUNT; + + pin_insert_group(&p->mnt_umount, &p->mnt_parent->mnt, &unmounted); if (mnt_has_parent(p)) { hlist_del_init(&p->mnt_mp_list); put_mountpoint(p->mnt_mp); mnt_add_count(p->mnt_parent, -1); - /* move the reference to mountpoint into ->mnt_ex_mountpoint */ - p->mnt_ex_mountpoint.dentry = p->mnt_mountpoint; - p->mnt_ex_mountpoint.mnt = &p->mnt_parent->mnt; + /* old mountpoint will be dropped when we can do that */ + p->mnt_ex_mountpoint = p->mnt_mountpoint; p->mnt_mountpoint = p->mnt.mnt_root; p->mnt_parent = p; p->mnt_mp = NULL; } change_mnt_propagation(p, MS_PRIVATE); - last = p; - } - if (last) { - last->mnt_hash.next = unmounted.first; - if (unmounted.first) - unmounted.first->pprev = &last->mnt_hash.next; - unmounted.first = tmp_list.first; - unmounted.first->pprev = &unmounted.first; } } |