diff options
| -rw-r--r-- | fs/namespace.c | 46 | ||||
| -rw-r--r-- | include/linux/namespace.h | 1 |
2 files changed, 23 insertions, 24 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 65f9c0ecc21..4abee9ab009 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -46,6 +46,7 @@ static int event; static struct list_head *mount_hashtable; static int hash_mask __read_mostly, hash_bits __read_mostly; static kmem_cache_t *mnt_cache; +static struct rw_semaphore namespace_sem; static inline unsigned long hash(struct vfsmount *mnt, struct dentry *dentry) { @@ -250,7 +251,7 @@ static void *m_start(struct seq_file *m, loff_t *pos) struct list_head *p; loff_t l = *pos; - down_read(&n->sem); + down_read(&namespace_sem); list_for_each(p, &n->list) if (!l--) return list_entry(p, struct vfsmount, mnt_list); @@ -267,8 +268,7 @@ static void *m_next(struct seq_file *m, void *v, loff_t *pos) static void m_stop(struct seq_file *m, void *v) { - struct namespace *n = m->private; - up_read(&n->sem); + up_read(&namespace_sem); } static inline void mangle(struct seq_file *m, const char *s) @@ -487,7 +487,7 @@ static int do_umount(struct vfsmount *mnt, int flags) return retval; } - down_write(¤t->namespace->sem); + down_write(&namespace_sem); spin_lock(&vfsmount_lock); event++; @@ -500,7 +500,7 @@ static int do_umount(struct vfsmount *mnt, int flags) spin_unlock(&vfsmount_lock); if (retval) security_sb_umount_busy(mnt); - up_write(¤t->namespace->sem); + up_write(&namespace_sem); release_mounts(&umount_list); return retval; } @@ -678,7 +678,7 @@ static int do_loopback(struct nameidata *nd, char *old_name, int recurse) if (err) return err; - down_write(¤t->namespace->sem); + down_write(&namespace_sem); err = -EINVAL; if (!check_mnt(nd->mnt) || !check_mnt(old_nd.mnt)) goto out; @@ -702,7 +702,7 @@ static int do_loopback(struct nameidata *nd, char *old_name, int recurse) } out: - up_write(¤t->namespace->sem); + up_write(&namespace_sem); path_release(&old_nd); return err; } @@ -750,7 +750,7 @@ static int do_move_mount(struct nameidata *nd, char *old_name) if (err) return err; - down_write(¤t->namespace->sem); + down_write(&namespace_sem); while (d_mountpoint(nd->dentry) && follow_down(&nd->mnt, &nd->dentry)) ; err = -EINVAL; @@ -795,7 +795,7 @@ out2: out1: up(&nd->dentry->d_inode->i_sem); out: - up_write(¤t->namespace->sem); + up_write(&namespace_sem); if (!err) path_release(&parent_nd); path_release(&old_nd); @@ -834,7 +834,7 @@ int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd, { int err; - down_write(¤t->namespace->sem); + down_write(&namespace_sem); /* Something was mounted here while we slept */ while (d_mountpoint(nd->dentry) && follow_down(&nd->mnt, &nd->dentry)) ; @@ -862,11 +862,11 @@ int do_add_mount(struct vfsmount *newmnt, struct nameidata *nd, list_add_tail(&newmnt->mnt_expire, fslist); spin_unlock(&vfsmount_lock); } - up_write(¤t->namespace->sem); + up_write(&namespace_sem); return 0; unlock: - up_write(¤t->namespace->sem); + up_write(&namespace_sem); mntput(newmnt); return err; } @@ -958,9 +958,9 @@ void mark_mounts_for_expiry(struct list_head *mounts) get_namespace(namespace); spin_unlock(&vfsmount_lock); - down_write(&namespace->sem); + down_write(&namespace_sem); expire_mount(mnt, mounts, &umounts); - up_write(&namespace->sem); + up_write(&namespace_sem); release_mounts(&umounts); mntput(mnt); put_namespace(namespace); @@ -1127,17 +1127,16 @@ int copy_namespace(int flags, struct task_struct *tsk) goto out; atomic_set(&new_ns->count, 1); - init_rwsem(&new_ns->sem); INIT_LIST_HEAD(&new_ns->list); init_waitqueue_head(&new_ns->poll); new_ns->event = 0; - down_write(&tsk->namespace->sem); + down_write(&namespace_sem); /* First pass: copy the tree topology */ new_ns->root = copy_tree(namespace->root, namespace->root->mnt_root, CL_EXPIRE); if (!new_ns->root) { - up_write(&tsk->namespace->sem); + up_write(&namespace_sem); kfree(new_ns); goto out; } @@ -1171,7 +1170,7 @@ int copy_namespace(int flags, struct task_struct *tsk) p = next_mnt(p, namespace->root); q = next_mnt(q, new_ns->root); } - up_write(&tsk->namespace->sem); + up_write(&namespace_sem); tsk->namespace = new_ns; @@ -1356,7 +1355,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root, user_nd.mnt = mntget(current->fs->rootmnt); user_nd.dentry = dget(current->fs->root); read_unlock(¤t->fs->lock); - down_write(¤t->namespace->sem); + down_write(&namespace_sem); down(&old_nd.dentry->d_inode->i_sem); error = -EINVAL; if (!check_mnt(user_nd.mnt)) @@ -1407,7 +1406,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root, path_release(&parent_nd); out2: up(&old_nd.dentry->d_inode->i_sem); - up_write(¤t->namespace->sem); + up_write(&namespace_sem); path_release(&user_nd); path_release(&old_nd); out1: @@ -1434,7 +1433,6 @@ static void __init init_mount_tree(void) panic("Can't allocate initial namespace"); atomic_set(&namespace->count, 1); INIT_LIST_HEAD(&namespace->list); - init_rwsem(&namespace->sem); init_waitqueue_head(&namespace->poll); namespace->event = 0; list_add(&mnt->mnt_list, &namespace->list); @@ -1459,6 +1457,8 @@ void __init mnt_init(unsigned long mempages) unsigned int nr_hash; int i; + init_rwsem(&namespace_sem); + mnt_cache = kmem_cache_create("mnt_cache", sizeof(struct vfsmount), 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL, NULL); @@ -1507,11 +1507,11 @@ void __put_namespace(struct namespace *namespace) LIST_HEAD(umount_list); namespace->root = NULL; spin_unlock(&vfsmount_lock); - down_write(&namespace->sem); + down_write(&namespace_sem); spin_lock(&vfsmount_lock); umount_tree(root, &umount_list); spin_unlock(&vfsmount_lock); - up_write(&namespace->sem); + up_write(&namespace_sem); release_mounts(&umount_list); kfree(namespace); } diff --git a/include/linux/namespace.h b/include/linux/namespace.h index 6f0f25d64c3..6731977c4c1 100644 --- a/include/linux/namespace.h +++ b/include/linux/namespace.h @@ -9,7 +9,6 @@ struct namespace { atomic_t count; struct vfsmount * root; struct list_head list; - struct rw_semaphore sem; wait_queue_head_t poll; int event; }; |