Commit 97216be0 authored by Al Viro's avatar Al Viro
Browse files

fold release_mounts() into namespace_unlock() 



... and provide namespace_lock() as a trivial wrapper;
switch to those two consistently.

Result is patterned after rtnl_lock/rtnl_unlock pair.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 328e6d90

fs/namespace.c

+30 −23
Original line number Original line Diff line number Diff line
@@ -1121,11 +1121,21 @@ EXPORT_SYMBOL(may_umount); 




static LIST_HEAD(unmounted);	/* protected by namespace_sem */

static LIST_HEAD(unmounted);	/* protected by namespace_sem */





static void release_mounts(struct list_head *head)

static void namespace_unlock(void)

{

{

	struct mount *mnt;

	struct mount *mnt;

	while (!list_empty(head)) {

	LIST_HEAD(head);

		mnt = list_first_entry(head, struct mount, mnt_hash);



	if (likely(list_empty(&unmounted))) {

		up_write(&namespace_sem);

		return;

	}



	list_splice_init(&unmounted, &head);

	up_write(&namespace_sem);



	while (!list_empty(&head)) {

		mnt = list_first_entry(&head, struct mount, mnt_hash);

		list_del_init(&mnt->mnt_hash);

		list_del_init(&mnt->mnt_hash);

		if (mnt_has_parent(mnt)) {

		if (mnt_has_parent(mnt)) {

			struct dentry *dentry;

			struct dentry *dentry;
@@ -1145,12 +1155,9 @@ static void release_mounts(struct list_head *head) 
	}

	}

}

}





static void namespace_unlock(void)

static inline void namespace_lock(void)

{

{

	LIST_HEAD(head);

	down_write(&namespace_sem);

	list_splice_init(&unmounted, &head);

	up_write(&namespace_sem);

	release_mounts(&head);

}

}





/*

/*
@@ -1256,7 +1263,7 @@ static int do_umount(struct mount *mnt, int flags) 
		return retval;

		return retval;

	}

	}





	down_write(&namespace_sem);

	namespace_lock();

	br_write_lock(&vfsmount_lock);

	br_write_lock(&vfsmount_lock);

	event++;

	event++;
@@ -1412,7 +1419,7 @@ out: 
struct vfsmount *collect_mounts(struct path *path)

struct vfsmount *collect_mounts(struct path *path)

{

{

	struct mount *tree;

	struct mount *tree;

	down_write(&namespace_sem);

	namespace_lock();

	tree = copy_tree(real_mount(path->mnt), path->dentry,

	tree = copy_tree(real_mount(path->mnt), path->dentry,

			 CL_COPY_ALL | CL_PRIVATE);

			 CL_COPY_ALL | CL_PRIVATE);

	namespace_unlock();

	namespace_unlock();
@@ -1423,7 +1430,7 @@ struct vfsmount *collect_mounts(struct path *path) 




void drop_collected_mounts(struct vfsmount *mnt)

void drop_collected_mounts(struct vfsmount *mnt)

{

{

	down_write(&namespace_sem);

	namespace_lock();

	br_write_lock(&vfsmount_lock);

	br_write_lock(&vfsmount_lock);

	umount_tree(real_mount(mnt), 0);

	umount_tree(real_mount(mnt), 0);

	br_write_unlock(&vfsmount_lock);

	br_write_unlock(&vfsmount_lock);
@@ -1593,18 +1600,18 @@ retry: 
		mutex_unlock(&dentry->d_inode->i_mutex);

		mutex_unlock(&dentry->d_inode->i_mutex);

		return ERR_PTR(-ENOENT);

		return ERR_PTR(-ENOENT);

	}

	}

	down_write(&namespace_sem);

	namespace_lock();

	mnt = lookup_mnt(path);

	mnt = lookup_mnt(path);

	if (likely(!mnt)) {

	if (likely(!mnt)) {

		struct mountpoint *mp = new_mountpoint(dentry);

		struct mountpoint *mp = new_mountpoint(dentry);

		if (IS_ERR(mp)) {

		if (IS_ERR(mp)) {

			up_write(&namespace_sem);

			namespace_unlock();

			mutex_unlock(&dentry->d_inode->i_mutex);

			mutex_unlock(&dentry->d_inode->i_mutex);

			return mp;

			return mp;

		}

		}

		return mp;

		return mp;

	}

	}

	up_write(&namespace_sem);

	namespace_unlock();

	mutex_unlock(&path->dentry->d_inode->i_mutex);

	mutex_unlock(&path->dentry->d_inode->i_mutex);

	path_put(path);

	path_put(path);

	path->mnt = mnt;

	path->mnt = mnt;
@@ -1667,7 +1674,7 @@ static int do_change_type(struct path *path, int flag) 
	if (!type)

	if (!type)

		return -EINVAL;

		return -EINVAL;





	down_write(&namespace_sem);

	namespace_lock();

	if (type == MS_SHARED) {

	if (type == MS_SHARED) {

		err = invent_group_ids(mnt, recurse);

		err = invent_group_ids(mnt, recurse);

		if (err)

		if (err)
@@ -1680,7 +1687,7 @@ static int do_change_type(struct path *path, int flag) 
	br_write_unlock(&vfsmount_lock);

	br_write_unlock(&vfsmount_lock);





 out_unlock:

 out_unlock:

	up_write(&namespace_sem);

	namespace_unlock();

	return err;

	return err;

}

}
@@ -2016,11 +2023,11 @@ int finish_automount(struct vfsmount *m, struct path *path) 
fail:

fail:

	/* remove m from any expiration list it may be on */

	/* remove m from any expiration list it may be on */

	if (!list_empty(&mnt->mnt_expire)) {

	if (!list_empty(&mnt->mnt_expire)) {

		down_write(&namespace_sem);

		namespace_lock();

		br_write_lock(&vfsmount_lock);

		br_write_lock(&vfsmount_lock);

		list_del_init(&mnt->mnt_expire);

		list_del_init(&mnt->mnt_expire);

		br_write_unlock(&vfsmount_lock);

		br_write_unlock(&vfsmount_lock);

		up_write(&namespace_sem);

		namespace_unlock();

	}

	}

	mntput(m);

	mntput(m);

	mntput(m);

	mntput(m);
@@ -2034,13 +2041,13 @@ fail: 
 */

 */

void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list)

void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list)

{

{

	down_write(&namespace_sem);

	namespace_lock();

	br_write_lock(&vfsmount_lock);

	br_write_lock(&vfsmount_lock);





	list_add_tail(&real_mount(mnt)->mnt_expire, expiry_list);

	list_add_tail(&real_mount(mnt)->mnt_expire, expiry_list);





	br_write_unlock(&vfsmount_lock);

	br_write_unlock(&vfsmount_lock);

	up_write(&namespace_sem);

	namespace_unlock();

}

}

EXPORT_SYMBOL(mnt_set_expiry);

EXPORT_SYMBOL(mnt_set_expiry);
@@ -2057,7 +2064,7 @@ void mark_mounts_for_expiry(struct list_head *mounts) 
	if (list_empty(mounts))

	if (list_empty(mounts))

		return;

		return;





	down_write(&namespace_sem);

	namespace_lock();

	br_write_lock(&vfsmount_lock);

	br_write_lock(&vfsmount_lock);





	/* extract from the expiration list every vfsmount that matches the

	/* extract from the expiration list every vfsmount that matches the
@@ -2373,7 +2380,7 @@ static struct mnt_namespace *dup_mnt_ns(struct mnt_namespace *mnt_ns, 
	if (IS_ERR(new_ns))

	if (IS_ERR(new_ns))

		return new_ns;

		return new_ns;





	down_write(&namespace_sem);

	namespace_lock();

	/* First pass: copy the tree topology */

	/* First pass: copy the tree topology */

	copy_flags = CL_COPY_ALL | CL_EXPIRE;

	copy_flags = CL_COPY_ALL | CL_EXPIRE;

	if (user_ns != mnt_ns->user_ns)

	if (user_ns != mnt_ns->user_ns)
@@ -2733,7 +2740,7 @@ void put_mnt_ns(struct mnt_namespace *ns) 
{

{

	if (!atomic_dec_and_test(&ns->count))

	if (!atomic_dec_and_test(&ns->count))

		return;

		return;

	down_write(&namespace_sem);

	namespace_lock();

	br_write_lock(&vfsmount_lock);

	br_write_lock(&vfsmount_lock);

	umount_tree(ns->root, 0);

	umount_tree(ns->root, 0);

	br_write_unlock(&vfsmount_lock);

	br_write_unlock(&vfsmount_lock);

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