unsigned int mnt_get_count(struct vfsmount *mnt)
{
#ifdef CONFIG_SMP
- unsigned int count = atomic_read(&mnt->mnt_longrefs);
+ unsigned int count = 0;
int cpu;
for_each_possible_cpu(cpu) {
#endif
}
-struct vfsmount *alloc_vfsmnt(const char *name)
+static struct vfsmount *alloc_vfsmnt(const char *name)
{
struct vfsmount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL);
if (mnt) {
if (!mnt->mnt_pcp)
goto out_free_devname;
- atomic_set(&mnt->mnt_longrefs, 1);
+ this_cpu_add(mnt->mnt_pcp->mnt_count, 1);
#else
mnt->mnt_count = 1;
mnt->mnt_writers = 0;
br_write_unlock(vfsmount_lock);
}
-void simple_set_mnt(struct vfsmount *mnt, struct super_block *sb)
-{
- mnt->mnt_sb = sb;
- mnt->mnt_root = dget(sb->s_root);
-}
-
-EXPORT_SYMBOL(simple_set_mnt);
-
-void free_vfsmnt(struct vfsmount *mnt)
+static void free_vfsmnt(struct vfsmount *mnt)
{
kfree(mnt->mnt_devname);
mnt_free_id(mnt);
list_add_tail(&mnt->mnt_child, &path->mnt->mnt_mounts);
}
+static inline void __mnt_make_longterm(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ atomic_inc(&mnt->mnt_longterm);
+#endif
+}
+
+/* needs vfsmount lock for write */
+static inline void __mnt_make_shortterm(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ atomic_dec(&mnt->mnt_longterm);
+#endif
+}
+
/*
* vfsmount lock must be held for write
*/
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);
list_add_tail(&mnt->mnt_hash, mount_hashtable +
return p;
}
+struct vfsmount *
+vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void *data)
+{
+ struct vfsmount *mnt;
+ struct dentry *root;
+
+ if (!type)
+ return ERR_PTR(-ENODEV);
+
+ mnt = alloc_vfsmnt(name);
+ if (!mnt)
+ return ERR_PTR(-ENOMEM);
+
+ if (flags & MS_KERNMOUNT)
+ mnt->mnt_flags = MNT_INTERNAL;
+
+ root = mount_fs(type, flags, name, data);
+ if (IS_ERR(root)) {
+ free_vfsmnt(mnt);
+ return ERR_CAST(root);
+ }
+
+ mnt->mnt_root = root;
+ mnt->mnt_sb = root->d_sb;
+ mnt->mnt_mountpoint = mnt->mnt_root;
+ mnt->mnt_parent = mnt;
+ return mnt;
+}
+EXPORT_SYMBOL_GPL(vfs_kern_mount);
+
static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root,
int flag)
{
deactivate_super(sb);
}
-#ifdef CONFIG_SMP
-static inline void __mntput(struct vfsmount *mnt, int longrefs)
+static void mntput_no_expire(struct vfsmount *mnt)
{
- if (!longrefs) {
put_again:
- br_read_lock(vfsmount_lock);
- if (likely(atomic_read(&mnt->mnt_longrefs))) {
- mnt_dec_count(mnt);
- br_read_unlock(vfsmount_lock);
- return;
- }
+#ifdef CONFIG_SMP
+ br_read_lock(vfsmount_lock);
+ if (likely(atomic_read(&mnt->mnt_longterm))) {
+ mnt_dec_count(mnt);
br_read_unlock(vfsmount_lock);
- } else {
- BUG_ON(!atomic_read(&mnt->mnt_longrefs));
- if (atomic_add_unless(&mnt->mnt_longrefs, -1, 1))
- return;
+ return;
}
+ br_read_unlock(vfsmount_lock);
br_write_lock(vfsmount_lock);
- if (!longrefs)
- mnt_dec_count(mnt);
- else
- atomic_dec(&mnt->mnt_longrefs);
+ mnt_dec_count(mnt);
if (mnt_get_count(mnt)) {
br_write_unlock(vfsmount_lock);
return;
}
- if (unlikely(mnt->mnt_pinned)) {
- mnt_add_count(mnt, mnt->mnt_pinned + 1);
- mnt->mnt_pinned = 0;
- br_write_unlock(vfsmount_lock);
- acct_auto_close_mnt(mnt);
- goto put_again;
- }
- br_write_unlock(vfsmount_lock);
- mntfree(mnt);
-}
#else
-static inline void __mntput(struct vfsmount *mnt, int longrefs)
-{
-put_again:
mnt_dec_count(mnt);
if (likely(mnt_get_count(mnt)))
return;
br_write_lock(vfsmount_lock);
+#endif
if (unlikely(mnt->mnt_pinned)) {
mnt_add_count(mnt, mnt->mnt_pinned + 1);
mnt->mnt_pinned = 0;
br_write_unlock(vfsmount_lock);
mntfree(mnt);
}
-#endif
-
-static void mntput_no_expire(struct vfsmount *mnt)
-{
- __mntput(mnt, 0);
-}
void mntput(struct vfsmount *mnt)
{
/* avoid cacheline pingpong, hope gcc doesn't get "smart" */
if (unlikely(mnt->mnt_expiry_mark))
mnt->mnt_expiry_mark = 0;
- __mntput(mnt, 0);
+ mntput_no_expire(mnt);
}
}
EXPORT_SYMBOL(mntput);
}
EXPORT_SYMBOL(mntget);
-void mntput_long(struct vfsmount *mnt)
-{
-#ifdef CONFIG_SMP
- if (mnt) {
- /* avoid cacheline pingpong, hope gcc doesn't get "smart" */
- if (unlikely(mnt->mnt_expiry_mark))
- mnt->mnt_expiry_mark = 0;
- __mntput(mnt, 1);
- }
-#else
- mntput(mnt);
-#endif
-}
-EXPORT_SYMBOL(mntput_long);
-
-struct vfsmount *mntget_long(struct vfsmount *mnt)
-{
-#ifdef CONFIG_SMP
- if (mnt)
- atomic_inc(&mnt->mnt_longrefs);
- return mnt;
-#else
- return mntget(mnt);
-#endif
-}
-EXPORT_SYMBOL(mntget_long);
-
void mnt_pin(struct vfsmount *mnt)
{
br_write_lock(vfsmount_lock);
int res = 0;
br_read_lock(vfsmount_lock);
- if (p->event != ns->event) {
- p->event = ns->event;
+ if (p->m.poll_event != ns->event) {
+ p->m.poll_event = ns->event;
res = 1;
}
br_read_unlock(vfsmount_lock);
int err = 0;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
- mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
+ if (mnt->mnt_sb->s_op->show_devname) {
+ err = mnt->mnt_sb->s_op->show_devname(m, mnt);
+ if (err)
+ goto out;
+ } else {
+ mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
+ }
seq_putc(m, ' ');
seq_path(m, &mnt_path, " \t\n\\");
seq_putc(m, ' ');
seq_printf(m, "%i %i %u:%u ", mnt->mnt_id, mnt->mnt_parent->mnt_id,
MAJOR(sb->s_dev), MINOR(sb->s_dev));
- seq_dentry(m, mnt->mnt_root, " \t\n\\");
+ if (sb->s_op->show_path)
+ err = sb->s_op->show_path(m, mnt);
+ else
+ seq_dentry(m, mnt->mnt_root, " \t\n\\");
+ if (err)
+ goto out;
seq_putc(m, ' ');
seq_path_root(m, &mnt_path, &root, " \t\n\\");
if (root.mnt != p->root.mnt || root.dentry != p->root.dentry) {
seq_puts(m, " - ");
show_type(m, sb);
seq_putc(m, ' ');
- mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
+ if (sb->s_op->show_devname)
+ err = sb->s_op->show_devname(m, mnt);
+ else
+ mangle(m, mnt->mnt_devname ? mnt->mnt_devname : "none");
+ if (err)
+ goto out;
seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw");
err = show_sb_opts(m, sb);
if (err)
int err = 0;
/* device */
- if (mnt->mnt_devname) {
+ if (mnt->mnt_sb->s_op->show_devname) {
seq_puts(m, "device ");
- mangle(m, mnt->mnt_devname);
- } else
- seq_puts(m, "no device");
+ err = mnt->mnt_sb->s_op->show_devname(m, mnt);
+ } else {
+ if (mnt->mnt_devname) {
+ seq_puts(m, "device ");
+ mangle(m, mnt->mnt_devname);
+ } else
+ seq_puts(m, "no device");
+ }
/* mount point */
seq_puts(m, " mounted on ");
/* optional statistics */
if (mnt->mnt_sb->s_op->show_stats) {
seq_putc(m, ' ');
- err = mnt->mnt_sb->s_op->show_stats(m, mnt);
+ if (!err)
+ err = mnt->mnt_sb->s_op->show_stats(m, mnt);
}
seq_putc(m, '\n');
dput(dentry);
mntput(m);
}
- mntput_long(mnt);
+ mntput(mnt);
}
}
*/
void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill)
{
+ LIST_HEAD(tmp_list);
struct vfsmount *p;
for (p = mnt; p; p = next_mnt(p, mnt))
- list_move(&p->mnt_hash, kill);
+ list_move(&p->mnt_hash, &tmp_list);
if (propagate)
- propagate_umount(kill);
+ propagate_umount(&tmp_list);
- list_for_each_entry(p, kill, mnt_hash) {
+ list_for_each_entry(p, &tmp_list, mnt_hash) {
list_del_init(&p->mnt_expire);
list_del_init(&p->mnt_list);
__touch_mnt_namespace(p->mnt_ns);
p->mnt_ns = NULL;
+ __mnt_make_shortterm(p);
list_del_init(&p->mnt_child);
if (p->mnt_parent != p) {
p->mnt_parent->mnt_ghosts++;
}
change_mnt_propagation(p, MS_PRIVATE);
}
+ list_splice(&tmp_list, kill);
}
static void shrink_submounts(struct vfsmount *mnt, struct list_head *umounts);
*/
br_write_lock(vfsmount_lock);
if (mnt_get_count(mnt) != 2) {
- br_write_lock(vfsmount_lock);
+ br_write_unlock(vfsmount_lock);
return -EBUSY;
}
br_write_unlock(vfsmount_lock);
return err;
}
+static int lock_mount(struct path *path)
+{
+ struct vfsmount *mnt;
+retry:
+ mutex_lock(&path->dentry->d_inode->i_mutex);
+ if (unlikely(cant_mount(path->dentry))) {
+ mutex_unlock(&path->dentry->d_inode->i_mutex);
+ return -ENOENT;
+ }
+ down_write(&namespace_sem);
+ mnt = lookup_mnt(path);
+ if (likely(!mnt))
+ return 0;
+ up_write(&namespace_sem);
+ mutex_unlock(&path->dentry->d_inode->i_mutex);
+ path_put(path);
+ path->mnt = mnt;
+ path->dentry = dget(mnt->mnt_root);
+ goto retry;
+}
+
+static void unlock_mount(struct path *path)
+{
+ up_write(&namespace_sem);
+ mutex_unlock(&path->dentry->d_inode->i_mutex);
+}
+
static int graft_tree(struct vfsmount *mnt, struct path *path)
{
- int err;
if (mnt->mnt_sb->s_flags & MS_NOUSER)
return -EINVAL;
S_ISDIR(mnt->mnt_root->d_inode->i_mode))
return -ENOTDIR;
- err = -ENOENT;
- mutex_lock(&path->dentry->d_inode->i_mutex);
- if (cant_mount(path->dentry))
- goto out_unlock;
+ if (d_unlinked(path->dentry))
+ return -ENOENT;
- if (!d_unlinked(path->dentry))
- err = attach_recursive_mnt(mnt, path, NULL);
-out_unlock:
- mutex_unlock(&path->dentry->d_inode->i_mutex);
- return err;
+ return attach_recursive_mnt(mnt, path, NULL);
}
/*
static int flags_to_propagation_type(int flags)
{
- int type = flags & ~MS_REC;
+ int type = flags & ~(MS_REC | MS_SILENT);
/* Fail if any non-propagation flags are set */
if (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
static int do_loopback(struct path *path, char *old_name,
int recurse)
{
+ LIST_HEAD(umount_list);
struct path old_path;
struct vfsmount *mnt = NULL;
int err = mount_is_safe(path);
return err;
if (!old_name || !*old_name)
return -EINVAL;
- err = kern_path(old_name, LOOKUP_FOLLOW, &old_path);
+ err = kern_path(old_name, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &old_path);
if (err)
return err;
- down_write(&namespace_sem);
+ err = lock_mount(path);
+ if (err)
+ goto out;
+
err = -EINVAL;
if (IS_MNT_UNBINDABLE(old_path.mnt))
- goto out;
+ goto out2;
if (!check_mnt(path->mnt) || !check_mnt(old_path.mnt))
- goto out;
+ goto out2;
err = -ENOMEM;
if (recurse)
mnt = clone_mnt(old_path.mnt, old_path.dentry, 0);
if (!mnt)
- goto out;
+ goto out2;
err = graft_tree(mnt, path);
if (err) {
- LIST_HEAD(umount_list);
-
br_write_lock(vfsmount_lock);
umount_tree(mnt, 0, &umount_list);
br_write_unlock(vfsmount_lock);
- release_mounts(&umount_list);
}
-
+out2:
+ unlock_mount(path);
+ release_mounts(&umount_list);
out:
- up_write(&namespace_sem);
path_put(&old_path);
return err;
}
if (path->dentry != path->mnt->mnt_root)
return -EINVAL;
+ err = security_sb_remount(sb, data);
+ if (err)
+ return err;
+
down_write(&sb->s_umount);
if (flags & MS_BIND)
err = change_mount_flags(path->mnt, flags);
if (err)
return err;
- down_write(&namespace_sem);
- while (d_mountpoint(path->dentry) &&
- follow_down(path))
- ;
- err = -EINVAL;
- if (!check_mnt(path->mnt) || !check_mnt(old_path.mnt))
+ err = lock_mount(path);
+ if (err < 0)
goto out;
- err = -ENOENT;
- mutex_lock(&path->dentry->d_inode->i_mutex);
- if (cant_mount(path->dentry))
+ err = -EINVAL;
+ if (!check_mnt(path->mnt) || !check_mnt(old_path.mnt))
goto out1;
if (d_unlinked(path->dentry))
* automatically */
list_del_init(&old_path.mnt->mnt_expire);
out1:
- mutex_unlock(&path->dentry->d_inode->i_mutex);
+ unlock_mount(path);
out:
- up_write(&namespace_sem);
if (!err)
path_put(&parent_path);
path_put(&old_path);
return err;
}
-/*
- * create a new mount for userspace and request it to be added into the
- * namespace's tree
- */
-static int do_new_mount(struct path *path, char *type, int flags,
- int mnt_flags, char *name, void *data)
+static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
{
- struct vfsmount *mnt;
-
- if (!type)
- return -EINVAL;
+ int err;
+ const char *subtype = strchr(fstype, '.');
+ if (subtype) {
+ subtype++;
+ err = -EINVAL;
+ if (!subtype[0])
+ goto err;
+ } else
+ subtype = "";
- /* we need capabilities... */
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
+ mnt->mnt_sb->s_subtype = kstrdup(subtype, GFP_KERNEL);
+ err = -ENOMEM;
+ if (!mnt->mnt_sb->s_subtype)
+ goto err;
+ return mnt;
- mnt = do_kern_mount(type, flags, name, data);
- if (IS_ERR(mnt))
- return PTR_ERR(mnt);
+ err:
+ mntput(mnt);
+ return ERR_PTR(err);
+}
- return do_add_mount(mnt, path, mnt_flags, NULL);
+struct vfsmount *
+do_kern_mount(const char *fstype, int flags, const char *name, void *data)
+{
+ struct file_system_type *type = get_fs_type(fstype);
+ struct vfsmount *mnt;
+ if (!type)
+ return ERR_PTR(-ENODEV);
+ mnt = vfs_kern_mount(type, flags, name, data);
+ if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
+ !mnt->mnt_sb->s_subtype)
+ mnt = fs_set_subtype(mnt, fstype);
+ put_filesystem(type);
+ return mnt;
}
+EXPORT_SYMBOL_GPL(do_kern_mount);
/*
* add a mount into a namespace's mount tree
- * - provide the option of adding the new mount to an expiration list
*/
-int do_add_mount(struct vfsmount *newmnt, struct path *path,
- int mnt_flags, struct list_head *fslist)
+static int do_add_mount(struct vfsmount *newmnt, struct path *path, int mnt_flags)
{
int err;
mnt_flags &= ~(MNT_SHARED | MNT_WRITE_HOLD | MNT_INTERNAL);
- down_write(&namespace_sem);
- /* Something was mounted here while we slept */
- while (d_mountpoint(path->dentry) &&
- follow_down(path))
- ;
+ err = lock_mount(path);
+ if (err)
+ return err;
+
err = -EINVAL;
if (!(mnt_flags & MNT_SHRINKABLE) && !check_mnt(path->mnt))
goto unlock;
goto unlock;
newmnt->mnt_flags = mnt_flags;
- if ((err = graft_tree(newmnt, path)))
- goto unlock;
+ err = graft_tree(newmnt, path);
- if (fslist) /* add to the specified expiration list */
- list_add_tail(&newmnt->mnt_expire, fslist);
+unlock:
+ unlock_mount(path);
+ return err;
+}
- up_write(&namespace_sem);
- return 0;
+/*
+ * create a new mount for userspace and request it to be added into the
+ * namespace's tree
+ */
+static int do_new_mount(struct path *path, char *type, int flags,
+ int mnt_flags, char *name, void *data)
+{
+ struct vfsmount *mnt;
+ int err;
-unlock:
- up_write(&namespace_sem);
- mntput_long(newmnt);
+ if (!type)
+ return -EINVAL;
+
+ /* we need capabilities... */
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mnt = do_kern_mount(type, flags, name, data);
+ if (IS_ERR(mnt))
+ return PTR_ERR(mnt);
+
+ err = do_add_mount(mnt, path, mnt_flags);
+ if (err)
+ mntput(mnt);
return err;
}
-EXPORT_SYMBOL_GPL(do_add_mount);
+int finish_automount(struct vfsmount *m, struct path *path)
+{
+ int err;
+ /* The new mount record should have at least 2 refs to prevent it being
+ * expired before we get a chance to add it
+ */
+ BUG_ON(mnt_get_count(m) < 2);
+
+ if (m->mnt_sb == path->mnt->mnt_sb &&
+ m->mnt_root == path->dentry) {
+ err = -ELOOP;
+ goto fail;
+ }
+
+ err = do_add_mount(m, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
+ if (!err)
+ return 0;
+fail:
+ /* remove m from any expiration list it may be on */
+ if (!list_empty(&m->mnt_expire)) {
+ down_write(&namespace_sem);
+ br_write_lock(vfsmount_lock);
+ list_del_init(&m->mnt_expire);
+ br_write_unlock(vfsmount_lock);
+ up_write(&namespace_sem);
+ }
+ mntput(m);
+ mntput(m);
+ return err;
+}
+
+/**
+ * mnt_set_expiry - Put a mount on an expiration list
+ * @mnt: The mount to list.
+ * @expiry_list: The list to add the mount to.
+ */
+void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list)
+{
+ down_write(&namespace_sem);
+ br_write_lock(vfsmount_lock);
+
+ list_add_tail(&mnt->mnt_expire, expiry_list);
+
+ br_write_unlock(vfsmount_lock);
+ up_write(&namespace_sem);
+}
+EXPORT_SYMBOL(mnt_set_expiry);
/*
* process a list of expirable mountpoints with the intent of discarding any
return new_ns;
}
+void mnt_make_longterm(struct vfsmount *mnt)
+{
+ __mnt_make_longterm(mnt);
+}
+
+void mnt_make_shortterm(struct vfsmount *mnt)
+{
+#ifdef CONFIG_SMP
+ 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.
q = new_ns->root;
while (p) {
q->mnt_ns = new_ns;
+ __mnt_make_longterm(q);
if (fs) {
if (p == fs->root.mnt) {
+ fs->root.mnt = mntget(q);
+ __mnt_make_longterm(q);
+ mnt_make_shortterm(p);
rootmnt = p;
- fs->root.mnt = mntget_long(q);
}
if (p == fs->pwd.mnt) {
+ fs->pwd.mnt = mntget(q);
+ __mnt_make_longterm(q);
+ mnt_make_shortterm(p);
pwdmnt = p;
- fs->pwd.mnt = mntget_long(q);
}
}
p = next_mnt(p, mnt_ns->root);
up_write(&namespace_sem);
if (rootmnt)
- mntput_long(rootmnt);
+ mntput(rootmnt);
if (pwdmnt)
- mntput_long(pwdmnt);
+ mntput(pwdmnt);
return new_ns;
}
new_ns = alloc_mnt_ns();
if (!IS_ERR(new_ns)) {
mnt->mnt_ns = new_ns;
+ __mnt_make_longterm(mnt);
new_ns->root = mnt;
list_add(&new_ns->list, &new_ns->root->mnt_list);
}
error = user_path_dir(new_root, &new);
if (error)
goto out0;
- error = -EINVAL;
- if (!check_mnt(new.mnt))
- goto out1;
error = user_path_dir(put_old, &old);
if (error)
goto out1;
error = security_sb_pivotroot(&old, &new);
- if (error) {
- path_put(&old);
- goto out1;
- }
+ if (error)
+ goto out2;
get_fs_root(current->fs, &root);
- down_write(&namespace_sem);
- mutex_lock(&old.dentry->d_inode->i_mutex);
+ error = lock_mount(&old);
+ if (error)
+ goto out3;
+
error = -EINVAL;
if (IS_MNT_SHARED(old.mnt) ||
IS_MNT_SHARED(new.mnt->mnt_parent) ||
IS_MNT_SHARED(root.mnt->mnt_parent))
- goto out2;
- if (!check_mnt(root.mnt))
- goto out2;
+ goto out4;
+ if (!check_mnt(root.mnt) || !check_mnt(new.mnt))
+ goto out4;
error = -ENOENT;
- if (cant_mount(old.dentry))
- goto out2;
if (d_unlinked(new.dentry))
- goto out2;
+ goto out4;
if (d_unlinked(old.dentry))
- goto out2;
+ goto out4;
error = -EBUSY;
if (new.mnt == root.mnt ||
old.mnt == root.mnt)
- goto out2; /* loop, on the same file system */
+ goto out4; /* loop, on the same file system */
error = -EINVAL;
if (root.mnt->mnt_root != root.dentry)
- goto out2; /* not a mountpoint */
+ goto out4; /* not a mountpoint */
if (root.mnt->mnt_parent == root.mnt)
- goto out2; /* not attached */
+ goto out4; /* not attached */
if (new.mnt->mnt_root != new.dentry)
- goto out2; /* not a mountpoint */
+ goto out4; /* not a mountpoint */
if (new.mnt->mnt_parent == new.mnt)
- goto out2; /* not attached */
+ goto out4; /* not attached */
/* make sure we can reach put_old from new_root */
tmp = old.mnt;
- br_write_lock(vfsmount_lock);
if (tmp != new.mnt) {
for (;;) {
if (tmp->mnt_parent == tmp)
- goto out3; /* already mounted on put_old */
+ goto out4; /* already mounted on put_old */
if (tmp->mnt_parent == new.mnt)
break;
tmp = tmp->mnt_parent;
}
if (!is_subdir(tmp->mnt_mountpoint, new.dentry))
- goto out3;
+ goto out4;
} else if (!is_subdir(old.dentry, new.dentry))
- goto out3;
+ goto out4;
+ br_write_lock(vfsmount_lock);
detach_mnt(new.mnt, &parent_path);
detach_mnt(root.mnt, &root_parent);
/* mount old root on put_old */
touch_mnt_namespace(current->nsproxy->mnt_ns);
br_write_unlock(vfsmount_lock);
chroot_fs_refs(&root, &new);
-
error = 0;
- path_put(&root_parent);
- path_put(&parent_path);
-out2:
- mutex_unlock(&old.dentry->d_inode->i_mutex);
- up_write(&namespace_sem);
+out4:
+ unlock_mount(&old);
+ if (!error) {
+ path_put(&root_parent);
+ path_put(&parent_path);
+ }
+out3:
path_put(&root);
+out2:
path_put(&old);
out1:
path_put(&new);
out0:
return error;
-out3:
- br_write_unlock(vfsmount_lock);
- goto out2;
}
static void __init init_mount_tree(void)
if (!mount_hashtable)
panic("Failed to allocate mount hash table\n");
- printk("Mount-cache hash table entries: %lu\n", HASH_SIZE);
+ printk(KERN_INFO "Mount-cache hash table entries: %lu\n", HASH_SIZE);
for (u = 0; u < HASH_SIZE; u++)
INIT_LIST_HEAD(&mount_hashtable[u]);
kfree(ns);
}
EXPORT_SYMBOL(put_mnt_ns);
+
+struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
+{
+ struct vfsmount *mnt;
+ mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
+ if (!IS_ERR(mnt)) {
+ /*
+ * it is a longterm mount, don't release mnt until
+ * we unmount before file sys is unregistered
+ */
+ mnt_make_longterm(mnt);
+ }
+ return mnt;
+}
+EXPORT_SYMBOL_GPL(kern_mount_data);
+
+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);
+ mntput(mnt);
+ }
+}
+EXPORT_SYMBOL(kern_unmount);
Code Review / linux-2.6.git / blobdiff