brlocks/lglocks: API cleanups

lglocks and brlocks are currently generated with some complicated macros
in lglock.h. But there's no reason to not just use common utility
functions and put all the data into a common data structure.

In preparation, this patch changes the API to look more like normal
function calls with pointers, not magic macros.

The patch is rather large because I move over all users in one go to keep
it bisectable. This impacts the VFS somewhat in terms of lines changed.
But no actual behaviour change.

[[e-mail]: checkpatch fixes]
Signed-off-by: Andi Kleen <[e-mail]>
Cc: Al Viro <[e-mail]>
Cc: Rusty Russell <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Rusty Russell <[e-mail]>
Signed-off-by: Al Viro <[e-mail]>

fs/dcache.c

···
 	bool slash = false;
 	int error = 0;
 
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	while (dentry != root->dentry || vfsmnt != root->mnt) {
 		struct dentry * parent;
 
···
 		error = prepend(buffer, buflen, "/", 1);
 
 out:
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 	return error;
 
 global_root:

fs/file_table.c

···
  */
 void file_sb_list_add(struct file *file, struct super_block *sb)
 {
-	lg_local_lock(files_lglock);
+	lg_local_lock(&files_lglock);
 	__file_sb_list_add(file, sb);
-	lg_local_unlock(files_lglock);
+	lg_local_unlock(&files_lglock);
 }
 
 /**
···
 void file_sb_list_del(struct file *file)
 {
 	if (!list_empty(&file->f_u.fu_list)) {
-		lg_local_lock_cpu(files_lglock, file_list_cpu(file));
+		lg_local_lock_cpu(&files_lglock, file_list_cpu(file));
 		list_del_init(&file->f_u.fu_list);
-		lg_local_unlock_cpu(files_lglock, file_list_cpu(file));
+		lg_local_unlock_cpu(&files_lglock, file_list_cpu(file));
 	}
 }
 
···
 	struct file *f;
 
 retry:
-	lg_global_lock(files_lglock);
+	lg_global_lock(&files_lglock);
 	do_file_list_for_each_entry(sb, f) {
 		struct vfsmount *mnt;
 		if (!S_ISREG(f->f_path.dentry->d_inode->i_mode))
···
 		file_release_write(f);
 		mnt = mntget(f->f_path.mnt);
 		/* This can sleep, so we can't hold the spinlock. */
-		lg_global_unlock(files_lglock);
+		lg_global_unlock(&files_lglock);
 		mnt_drop_write(mnt);
 		mntput(mnt);
 		goto retry;
 	} while_file_list_for_each_entry;
-	lg_global_unlock(files_lglock);
+	lg_global_unlock(&files_lglock);
 }
 
 void __init files_init(unsigned long mempages)
···
 	n = (mempages * (PAGE_SIZE / 1024)) / 10;
 	files_stat.max_files = max_t(unsigned long, n, NR_FILE);
 	files_defer_init();
-	lg_lock_init(files_lglock);
+	lg_lock_init(&files_lglock, "files_lglock");
 	percpu_counter_init(&nr_files, 0);
 } 

fs/namei.c

···
 	mntget(nd->path.mnt);
 
 	rcu_read_unlock();
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 	nd->flags &= ~LOOKUP_RCU;
 	return 0;
 
···
 		if (unlikely(!__d_rcu_to_refcount(dentry, nd->seq))) {
 			spin_unlock(&dentry->d_lock);
 			rcu_read_unlock();
-			br_read_unlock(vfsmount_lock);
+			br_read_unlock(&vfsmount_lock);
 			return -ECHILD;
 		}
 		BUG_ON(nd->inode != dentry->d_inode);
 		spin_unlock(&dentry->d_lock);
 		mntget(nd->path.mnt);
 		rcu_read_unlock();
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 	}
 
 	if (likely(!(nd->flags & LOOKUP_JUMPED)))
···
 	struct mount *parent;
 	struct dentry *mountpoint;
 
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	parent = mnt->mnt_parent;
 	if (&parent->mnt == path->mnt) {
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 		return 0;
 	}
 	mntget(&parent->mnt);
 	mountpoint = dget(mnt->mnt_mountpoint);
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 	dput(path->dentry);
 	path->dentry = mountpoint;
 	mntput(path->mnt);
···
 	if (!(nd->flags & LOOKUP_ROOT))
 		nd->root.mnt = NULL;
 	rcu_read_unlock();
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 	return -ECHILD;
 }
 
···
 		if (!(nd->flags & LOOKUP_ROOT))
 			nd->root.mnt = NULL;
 		rcu_read_unlock();
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 	}
 }
 
···
 		nd->path = nd->root;
 		nd->inode = inode;
 		if (flags & LOOKUP_RCU) {
-			br_read_lock(vfsmount_lock);
+			br_read_lock(&vfsmount_lock);
 			rcu_read_lock();
 			nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
 		} else {
···
 
 	if (*name=='/') {
 		if (flags & LOOKUP_RCU) {
-			br_read_lock(vfsmount_lock);
+			br_read_lock(&vfsmount_lock);
 			rcu_read_lock();
 			set_root_rcu(nd);
 		} else {
···
 			struct fs_struct *fs = current->fs;
 			unsigned seq;
 
-			br_read_lock(vfsmount_lock);
+			br_read_lock(&vfsmount_lock);
 			rcu_read_lock();
 
 			do {
···
 			if (fput_needed)
 				*fp = file;
 			nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq);
-			br_read_lock(vfsmount_lock);
+			br_read_lock(&vfsmount_lock);
 			rcu_read_lock();
 		} else {
 			path_get(&file->f_path);

fs/namespace.c

···
 {
 	int ret = 0;
 
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
 	/*
 	 * After storing MNT_WRITE_HOLD, we'll read the counters. This store
···
 	 */
 	smp_wmb();
 	mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	return ret;
 }
 
 static void __mnt_unmake_readonly(struct mount *mnt)
 {
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	mnt->mnt.mnt_flags &= ~MNT_READONLY;
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 }
 
 int sb_prepare_remount_readonly(struct super_block *sb)
···
 	if (atomic_long_read(&sb->s_remove_count))
 		return -EBUSY;
 
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	list_for_each_entry(mnt, &sb->s_mounts, mnt_instance) {
 		if (!(mnt->mnt.mnt_flags & MNT_READONLY)) {
 			mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
···
 		if (mnt->mnt.mnt_flags & MNT_WRITE_HOLD)
 			mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 
 	return err;
 }
···
 {
 	struct mount *child_mnt;
 
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	child_mnt = __lookup_mnt(path->mnt, path->dentry, 1);
 	if (child_mnt) {
 		mnt_add_count(child_mnt, 1);
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 		return &child_mnt->mnt;
 	} else {
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 		return NULL;
 	}
 }
···
 	mnt->mnt.mnt_sb = root->d_sb;
 	mnt->mnt_mountpoint = mnt->mnt.mnt_root;
 	mnt->mnt_parent = mnt;
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	list_add_tail(&mnt->mnt_instance, &root->d_sb->s_mounts);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	return &mnt->mnt;
 }
 EXPORT_SYMBOL_GPL(vfs_kern_mount);
···
 		mnt->mnt.mnt_root = dget(root);
 		mnt->mnt_mountpoint = mnt->mnt.mnt_root;
 		mnt->mnt_parent = mnt;
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		list_add_tail(&mnt->mnt_instance, &sb->s_mounts);
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 
 		if (flag & CL_SLAVE) {
 			list_add(&mnt->mnt_slave, &old->mnt_slave_list);
···
 {
 put_again:
 #ifdef CONFIG_SMP
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	if (likely(atomic_read(&mnt->mnt_longterm))) {
 		mnt_add_count(mnt, -1);
-		br_read_unlock(vfsmount_lock);
+		br_read_unlock(&vfsmount_lock);
 		return;
 	}
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	mnt_add_count(mnt, -1);
 	if (mnt_get_count(mnt)) {
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 		return;
 	}
 #else
 	mnt_add_count(mnt, -1);
 	if (likely(mnt_get_count(mnt)))
 		return;
-	br_write_lock(vfsmount_lock);
+	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);
+		br_write_unlock(&vfsmount_lock);
 		acct_auto_close_mnt(&mnt->mnt);
 		goto put_again;
 	}
+
 	list_del(&mnt->mnt_instance);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	mntfree(mnt);
 }
 
···
 
 void mnt_pin(struct vfsmount *mnt)
 {
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	real_mount(mnt)->mnt_pinned++;
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 }
 EXPORT_SYMBOL(mnt_pin);
 
 void mnt_unpin(struct vfsmount *m)
 {
 	struct mount *mnt = real_mount(m);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	if (mnt->mnt_pinned) {
 		mnt_add_count(mnt, 1);
 		mnt->mnt_pinned--;
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 }
 EXPORT_SYMBOL(mnt_unpin);
 
···
 	BUG_ON(!m);
 
 	/* write lock needed for mnt_get_count */
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	for (p = mnt; p; p = next_mnt(p, mnt)) {
 		actual_refs += mnt_get_count(p);
 		minimum_refs += 2;
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 
 	if (actual_refs > minimum_refs)
 		return 0;
···
 {
 	int ret = 1;
 	down_read(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	if (propagate_mount_busy(real_mount(mnt), 2))
 		ret = 0;
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_read(&namespace_sem);
 	return ret;
 }
···
 			struct dentry *dentry;
 			struct mount *m;
 
-			br_write_lock(vfsmount_lock);
+			br_write_lock(&vfsmount_lock);
 			dentry = mnt->mnt_mountpoint;
 			m = mnt->mnt_parent;
 			mnt->mnt_mountpoint = mnt->mnt.mnt_root;
 			mnt->mnt_parent = mnt;
 			m->mnt_ghosts--;
-			br_write_unlock(vfsmount_lock);
+			br_write_unlock(&vfsmount_lock);
 			dput(dentry);
 			mntput(&m->mnt);
 		}
···
 		 * probably don't strictly need the lock here if we examined
 		 * all race cases, but it's a slowpath.
 		 */
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		if (mnt_get_count(mnt) != 2) {
-			br_write_unlock(vfsmount_lock);
+			br_write_unlock(&vfsmount_lock);
 			return -EBUSY;
 		}
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 
 		if (!xchg(&mnt->mnt_expiry_mark, 1))
 			return -EAGAIN;
···
 	}
 
 	down_write(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	event++;
 
 	if (!(flags & MNT_DETACH))
···
 			umount_tree(mnt, 1, &umount_list);
 		retval = 0;
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_write(&namespace_sem);
 	release_mounts(&umount_list);
 	return retval;
···
 			q = clone_mnt(p, p->mnt.mnt_root, flag);
 			if (!q)
 				goto Enomem;
-			br_write_lock(vfsmount_lock);
+			br_write_lock(&vfsmount_lock);
 			list_add_tail(&q->mnt_list, &res->mnt_list);
 			attach_mnt(q, &path);
-			br_write_unlock(vfsmount_lock);
+			br_write_unlock(&vfsmount_lock);
 		}
 	}
 	return res;
 Enomem:
 	if (res) {
 		LIST_HEAD(umount_list);
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		umount_tree(res, 0, &umount_list);
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 		release_mounts(&umount_list);
 	}
 	return NULL;
···
 {
 	LIST_HEAD(umount_list);
 	down_write(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	umount_tree(real_mount(mnt), 0, &umount_list);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_write(&namespace_sem);
 	release_mounts(&umount_list);
 }
···
 	if (err)
 		goto out_cleanup_ids;
 
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 
 	if (IS_MNT_SHARED(dest_mnt)) {
 		for (p = source_mnt; p; p = next_mnt(p, source_mnt))
···
 		list_del_init(&child->mnt_hash);
 		commit_tree(child);
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 
 	return 0;
 
···
 			goto out_unlock;
 	}
 
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	for (m = mnt; m; m = (recurse ? next_mnt(m, mnt) : NULL))
 		change_mnt_propagation(m, type);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 
  out_unlock:
 	up_write(&namespace_sem);
···
 
 	err = graft_tree(mnt, path);
 	if (err) {
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		umount_tree(mnt, 0, &umount_list);
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 	}
 out2:
 	unlock_mount(path);
···
 	else
 		err = do_remount_sb(sb, flags, data, 0);
 	if (!err) {
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		mnt_flags |= mnt->mnt.mnt_flags & MNT_PROPAGATION_MASK;
 		mnt->mnt.mnt_flags = mnt_flags;
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 	}
 	up_write(&sb->s_umount);
 	if (!err) {
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		touch_mnt_namespace(mnt->mnt_ns);
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 	}
 	return err;
 }
···
 	/* remove m from any expiration list it may be on */
 	if (!list_empty(&mnt->mnt_expire)) {
 		down_write(&namespace_sem);
-		br_write_lock(vfsmount_lock);
+		br_write_lock(&vfsmount_lock);
 		list_del_init(&mnt->mnt_expire);
-		br_write_unlock(vfsmount_lock);
+		br_write_unlock(&vfsmount_lock);
 		up_write(&namespace_sem);
 	}
 	mntput(m);
···
 void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list)
 {
 	down_write(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 
 	list_add_tail(&real_mount(mnt)->mnt_expire, expiry_list);
 
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_write(&namespace_sem);
 }
 EXPORT_SYMBOL(mnt_set_expiry);
···
 		return;
 
 	down_write(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 
 	/* extract from the expiration list every vfsmount that matches the
 	 * following criteria:
···
 		touch_mnt_namespace(mnt->mnt_ns);
 		umount_tree(mnt, 1, &umounts);
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_write(&namespace_sem);
 
 	release_mounts(&umounts);
···
 	struct mount *mnt = real_mount(m);
 	if (atomic_add_unless(&mnt->mnt_longterm, -1, 1))
 		return;
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	atomic_dec(&mnt->mnt_longterm);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 #endif
 }
 
···
 		return ERR_PTR(-ENOMEM);
 	}
 	new_ns->root = new;
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	list_add_tail(&new_ns->list, &new->mnt_list);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 
 	/*
 	 * Second pass: switch the tsk->fs->* elements and mark new vfsmounts
···
 int path_is_under(struct path *path1, struct path *path2)
 {
 	int res;
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	res = is_path_reachable(real_mount(path1->mnt), path1->dentry, path2);
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 	return res;
 }
 EXPORT_SYMBOL(path_is_under);
···
 	/* make sure we can reach put_old from new_root */
 	if (!is_path_reachable(real_mount(old.mnt), old.dentry, &new))
 		goto out4;
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	detach_mnt(new_mnt, &parent_path);
 	detach_mnt(root_mnt, &root_parent);
 	/* mount old root on put_old */
···
 	/* mount new_root on / */
 	attach_mnt(new_mnt, &root_parent);
 	touch_mnt_namespace(current->nsproxy->mnt_ns);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	chroot_fs_refs(&root, &new);
 	error = 0;
 out4:
···
 	for (u = 0; u < HASH_SIZE; u++)
 		INIT_LIST_HEAD(&mount_hashtable[u]);
 
-	br_lock_init(vfsmount_lock);
+	br_lock_init(&vfsmount_lock);
 
 	err = sysfs_init();
 	if (err)
···
 	if (!atomic_dec_and_test(&ns->count))
 		return;
 	down_write(&namespace_sem);
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	umount_tree(ns->root, 0, &umount_list);
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	up_write(&namespace_sem);
 	release_mounts(&umount_list);
 	kfree(ns);

fs/pnode.c

···
 		prev_src_mnt  = child;
 	}
 out:
-	br_write_lock(vfsmount_lock);
+	br_write_lock(&vfsmount_lock);
 	while (!list_empty(&tmp_list)) {
 		child = list_first_entry(&tmp_list, struct mount, mnt_hash);
 		umount_tree(child, 0, &umount_list);
 	}
-	br_write_unlock(vfsmount_lock);
+	br_write_unlock(&vfsmount_lock);
 	release_mounts(&umount_list);
 	return ret;
 }

fs/proc_namespace.c

···
 
 	poll_wait(file, &p->ns->poll, wait);
 
-	br_read_lock(vfsmount_lock);
+	br_read_lock(&vfsmount_lock);
 	if (p->m.poll_event != ns->event) {
 		p->m.poll_event = ns->event;
 		res |= POLLERR | POLLPRI;
 	}
-	br_read_unlock(vfsmount_lock);
+	br_read_unlock(&vfsmount_lock);
 
 	return res;
 }