diff options
| -rw-r--r-- | fs/dcache.c | 2 | ||||
| -rw-r--r-- | fs/fs_struct.c | 32 | ||||
| -rw-r--r-- | fs/internal.h | 2 | ||||
| -rw-r--r-- | fs/mount.h | 9 | ||||
| -rw-r--r-- | fs/namespace.c | 53 |
5 files changed, 26 insertions, 72 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 40469044088d..44acb5b29ae4 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2622,7 +2622,7 @@ global_root: if (!slash) error = prepend(buffer, buflen, "/", 1); if (!error) - error = real_mount(vfsmnt)->mnt_ns ? 1 : 2; + error = is_mounted(vfsmnt) ? 1 : 2; goto out; } diff --git a/fs/fs_struct.c b/fs/fs_struct.c index e159e682ad4c..5df4775fea03 100644 --- a/fs/fs_struct.c +++ b/fs/fs_struct.c @@ -6,18 +6,6 @@ #include <linux/fs_struct.h> #include "internal.h" -static inline void path_get_longterm(struct path *path) -{ - path_get(path); - mnt_make_longterm(path->mnt); -} - -static inline void path_put_longterm(struct path *path) -{ - mnt_make_shortterm(path->mnt); - path_put(path); -} - /* * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values. * It can block. @@ -26,7 +14,7 @@ void set_fs_root(struct fs_struct *fs, struct path *path) { struct path old_root; - path_get_longterm(path); + path_get(path); spin_lock(&fs->lock); write_seqcount_begin(&fs->seq); old_root = fs->root; @@ -34,7 +22,7 @@ void set_fs_root(struct fs_struct *fs, struct path *path) write_seqcount_end(&fs->seq); spin_unlock(&fs->lock); if (old_root.dentry) - path_put_longterm(&old_root); + path_put(&old_root); } /* @@ -45,7 +33,7 @@ void set_fs_pwd(struct fs_struct *fs, struct path *path) { struct path old_pwd; - path_get_longterm(path); + path_get(path); spin_lock(&fs->lock); write_seqcount_begin(&fs->seq); old_pwd = fs->pwd; @@ -54,7 +42,7 @@ void set_fs_pwd(struct fs_struct *fs, struct path *path) spin_unlock(&fs->lock); if (old_pwd.dentry) - path_put_longterm(&old_pwd); + path_put(&old_pwd); } static inline int replace_path(struct path *p, const struct path *old, const struct path *new) @@ -84,7 +72,7 @@ void chroot_fs_refs(struct path *old_root, struct path *new_root) write_seqcount_end(&fs->seq); while (hits--) { count++; - path_get_longterm(new_root); + path_get(new_root); } spin_unlock(&fs->lock); } @@ -92,13 +80,13 @@ void chroot_fs_refs(struct path *old_root, struct path *new_root) } while_each_thread(g, p); read_unlock(&tasklist_lock); while (count--) - path_put_longterm(old_root); + path_put(old_root); } void free_fs_struct(struct fs_struct *fs) { - path_put_longterm(&fs->root); - path_put_longterm(&fs->pwd); + path_put(&fs->root); + path_put(&fs->pwd); kmem_cache_free(fs_cachep, fs); } @@ -132,9 +120,9 @@ struct fs_struct *copy_fs_struct(struct fs_struct *old) spin_lock(&old->lock); fs->root = old->root; - path_get_longterm(&fs->root); + path_get(&fs->root); fs->pwd = old->pwd; - path_get_longterm(&fs->pwd); + path_get(&fs->pwd); spin_unlock(&old->lock); } return fs; diff --git a/fs/internal.h b/fs/internal.h index 18bc216ea09d..d2a23ff61b40 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -50,8 +50,6 @@ extern int copy_mount_string(const void __user *, char **); extern struct vfsmount *lookup_mnt(struct path *); extern int finish_automount(struct vfsmount *, struct path *); -extern void mnt_make_longterm(struct vfsmount *); -extern void mnt_make_shortterm(struct vfsmount *); extern int sb_prepare_remount_readonly(struct super_block *); extern void __init mnt_init(void); diff --git a/fs/mount.h b/fs/mount.h index 4ef36d93e5a2..05a2a1185efc 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -22,7 +22,6 @@ struct mount { struct vfsmount mnt; #ifdef CONFIG_SMP struct mnt_pcp __percpu *mnt_pcp; - atomic_t mnt_longterm; /* how many of the refs are longterm */ #else int mnt_count; int mnt_writers; @@ -49,6 +48,8 @@ struct mount { int mnt_ghosts; }; +#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ + static inline struct mount *real_mount(struct vfsmount *mnt) { return container_of(mnt, struct mount, mnt); @@ -59,6 +60,12 @@ static inline int mnt_has_parent(struct mount *mnt) return mnt != mnt->mnt_parent; } +static inline int is_mounted(struct vfsmount *mnt) +{ + /* neither detached nor internal? */ + return !IS_ERR_OR_NULL(real_mount(mnt)); +} + extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int); static inline void get_mnt_ns(struct mnt_namespace *ns) diff --git a/fs/namespace.c b/fs/namespace.c index 1e4a5fe3d7b7..a524ea4dbd80 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -621,21 +621,6 @@ static void attach_mnt(struct mount *mnt, struct path *path) list_add_tail(&mnt->mnt_child, &real_mount(path->mnt)->mnt_mounts); } -static inline void __mnt_make_longterm(struct mount *mnt) -{ -#ifdef CONFIG_SMP - atomic_inc(&mnt->mnt_longterm); -#endif -} - -/* needs vfsmount lock for write */ -static inline void __mnt_make_shortterm(struct mount *mnt) -{ -#ifdef CONFIG_SMP - atomic_dec(&mnt->mnt_longterm); -#endif -} - /* * vfsmount lock must be held for write */ @@ -649,10 +634,8 @@ static void commit_tree(struct mount *mnt) BUG_ON(parent == mnt); list_add_tail(&head, &mnt->mnt_list); - list_for_each_entry(m, &head, mnt_list) { + list_for_each_entry(m, &head, mnt_list) m->mnt_ns = n; - __mnt_make_longterm(m); - } list_splice(&head, n->list.prev); @@ -804,7 +787,8 @@ static void mntput_no_expire(struct mount *mnt) put_again: #ifdef CONFIG_SMP br_read_lock(&vfsmount_lock); - if (likely(atomic_read(&mnt->mnt_longterm))) { + if (likely(mnt->mnt_ns)) { + /* shouldn't be the last one */ mnt_add_count(mnt, -1); br_read_unlock(&vfsmount_lock); return; @@ -1074,8 +1058,6 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill) list_del_init(&p->mnt_expire); list_del_init(&p->mnt_list); __touch_mnt_namespace(p->mnt_ns); - if (p->mnt_ns) - __mnt_make_shortterm(p); p->mnt_ns = NULL; list_del_init(&p->mnt_child); if (mnt_has_parent(p)) { @@ -2209,23 +2191,6 @@ static struct mnt_namespace *alloc_mnt_ns(void) return new_ns; } -void mnt_make_longterm(struct vfsmount *mnt) -{ - __mnt_make_longterm(real_mount(mnt)); -} - -void mnt_make_shortterm(struct vfsmount *m) -{ -#ifdef CONFIG_SMP - struct mount *mnt = real_mount(m); - if (atomic_add_unless(&mnt->mnt_longterm, -1, 1)) - return; - br_write_lock(&vfsmount_lock); - atomic_dec(&mnt->mnt_longterm); - br_write_unlock(&vfsmount_lock); -#endif -} - /* * Allocate a new namespace structure and populate it with contents * copied from the namespace of the passed in task structure. @@ -2265,18 +2230,13 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns, q = new; while (p) { q->mnt_ns = new_ns; - __mnt_make_longterm(q); if (fs) { if (&p->mnt == fs->root.mnt) { fs->root.mnt = mntget(&q->mnt); - __mnt_make_longterm(q); - mnt_make_shortterm(&p->mnt); rootmnt = &p->mnt; } if (&p->mnt == fs->pwd.mnt) { fs->pwd.mnt = mntget(&q->mnt); - __mnt_make_longterm(q); - mnt_make_shortterm(&p->mnt); pwdmnt = &p->mnt; } } @@ -2320,7 +2280,6 @@ static struct mnt_namespace *create_mnt_ns(struct vfsmount *m) if (!IS_ERR(new_ns)) { struct mount *mnt = real_mount(m); mnt->mnt_ns = new_ns; - __mnt_make_longterm(mnt); new_ns->root = mnt; list_add(&new_ns->list, &mnt->mnt_list); } else { @@ -2615,7 +2574,7 @@ struct vfsmount *kern_mount_data(struct file_system_type *type, void *data) * it is a longterm mount, don't release mnt until * we unmount before file sys is unregistered */ - mnt_make_longterm(mnt); + real_mount(mnt)->mnt_ns = MNT_NS_INTERNAL; } return mnt; } @@ -2625,7 +2584,9 @@ void kern_unmount(struct vfsmount *mnt) { /* release long term mount so mount point can be released */ if (!IS_ERR_OR_NULL(mnt)) { - mnt_make_shortterm(mnt); + br_write_lock(&vfsmount_lock); + real_mount(mnt)->mnt_ns = NULL; + br_write_unlock(&vfsmount_lock); mntput(mnt); } } |