mm: Convert all PageMovable users to movable_operations

These drivers are rather uncomfortably hammered into the
address_space_operations hole.  They aren't filesystems and don't behave
like filesystems.  They just need their own movable_operations structure,
which we can point to directly from page->mapping.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

2 files changed, 5 insertions, 103 deletions

diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c
index 086ce77d9074..85dd6aa33df6 100644
--- a/drivers/misc/vmw_balloon.c
+++ b/drivers/misc/vmw_balloon.c
@@ -29,8 +29,6 @@
 #include <linux/rwsem.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
-#include <linux/mount.h>
-#include <linux/pseudo_fs.h>
 #include <linux/balloon_compaction.h>
 #include <linux/vmw_vmci_defs.h>
 #include <linux/vmw_vmci_api.h>
@@ -1730,20 +1728,6 @@ static inline void vmballoon_debugfs_exit(struct vmballoon *b)
 
 
 #ifdef CONFIG_BALLOON_COMPACTION
-
-static int vmballoon_init_fs_context(struct fs_context *fc)
-{
-	return init_pseudo(fc, BALLOON_VMW_MAGIC) ? 0 : -ENOMEM;
-}
-
-static struct file_system_type vmballoon_fs = {
-	.name           	= "balloon-vmware",
-	.init_fs_context	= vmballoon_init_fs_context,
-	.kill_sb        	= kill_anon_super,
-};
-
-static struct vfsmount *vmballoon_mnt;
-
 /**
  * vmballoon_migratepage() - migrates a balloon page.
  * @b_dev_info: balloon device information descriptor.
@@ -1863,21 +1847,6 @@ out_unlock:
 }
 
 /**
- * vmballoon_compaction_deinit() - removes compaction related data.
- *
- * @b: pointer to the balloon.
- */
-static void vmballoon_compaction_deinit(struct vmballoon *b)
-{
-	if (!IS_ERR(b->b_dev_info.inode))
-		iput(b->b_dev_info.inode);
-
-	b->b_dev_info.inode = NULL;
-	kern_unmount(vmballoon_mnt);
-	vmballoon_mnt = NULL;
-}
-
-/**
  * vmballoon_compaction_init() - initialized compaction for the balloon.
  *
  * @b: pointer to the balloon.
@@ -1888,33 +1857,15 @@ static void vmballoon_compaction_deinit(struct vmballoon *b)
  *
  * Return: zero on success or error code on failure.
  */
-static __init int vmballoon_compaction_init(struct vmballoon *b)
+static __init void vmballoon_compaction_init(struct vmballoon *b)
 {
-	vmballoon_mnt = kern_mount(&vmballoon_fs);
-	if (IS_ERR(vmballoon_mnt))
-		return PTR_ERR(vmballoon_mnt);
-
 	b->b_dev_info.migratepage = vmballoon_migratepage;
-	b->b_dev_info.inode = alloc_anon_inode(vmballoon_mnt->mnt_sb);
-
-	if (IS_ERR(b->b_dev_info.inode))
-		return PTR_ERR(b->b_dev_info.inode);
-
-	b->b_dev_info.inode->i_mapping->a_ops = &balloon_aops;
-	return 0;
 }
 
 #else /* CONFIG_BALLOON_COMPACTION */
-
-static void vmballoon_compaction_deinit(struct vmballoon *b)
-{
-}
-
-static int vmballoon_compaction_init(struct vmballoon *b)
+static inline void vmballoon_compaction_init(struct vmballoon *b)
 {
-	return 0;
 }
-
 #endif /* CONFIG_BALLOON_COMPACTION */
 
 static int __init vmballoon_init(void)
@@ -1939,9 +1890,7 @@ static int __init vmballoon_init(void)
 	 * balloon_devinfo_init() .
 	 */
 	balloon_devinfo_init(&balloon.b_dev_info);
-	error = vmballoon_compaction_init(&balloon);
-	if (error)
-		goto fail;
+	vmballoon_compaction_init(&balloon);
 
 	INIT_LIST_HEAD(&balloon.huge_pages);
 	spin_lock_init(&balloon.comm_lock);
@@ -1958,7 +1907,6 @@ static int __init vmballoon_init(void)
 	return 0;
 fail:
 	vmballoon_unregister_shrinker(&balloon);
-	vmballoon_compaction_deinit(&balloon);
 	return error;
 }
 
@@ -1985,8 +1933,5 @@ static void __exit vmballoon_exit(void)
 	 */
 	vmballoon_send_start(&balloon, 0);
 	vmballoon_pop(&balloon);
-
-	/* Only once we popped the balloon, compaction can be deinit */
-	vmballoon_compaction_deinit(&balloon);
 }
 module_exit(vmballoon_exit);
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index b9737da6c4dd..bd360b91e9d3 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -17,9 +17,6 @@
 #include <linux/oom.h>
 #include <linux/wait.h>
 #include <linux/mm.h>
-#include <linux/mount.h>
-#include <linux/magic.h>
-#include <linux/pseudo_fs.h>
 #include <linux/page_reporting.h>
 
 /*
@@ -42,10 +39,6 @@
 	(1 << (VIRTIO_BALLOON_HINT_BLOCK_ORDER + PAGE_SHIFT))
 #define VIRTIO_BALLOON_HINT_BLOCK_PAGES (1 << VIRTIO_BALLOON_HINT_BLOCK_ORDER)
 
-#ifdef CONFIG_BALLOON_COMPACTION
-static struct vfsmount *balloon_mnt;
-#endif
-
 enum virtio_balloon_vq {
 	VIRTIO_BALLOON_VQ_INFLATE,
 	VIRTIO_BALLOON_VQ_DEFLATE,
@@ -805,18 +798,6 @@ static int virtballoon_migratepage(struct balloon_dev_info *vb_dev_info,
 
 	return MIGRATEPAGE_SUCCESS;
 }
-
-static int balloon_init_fs_context(struct fs_context *fc)
-{
-	return init_pseudo(fc, BALLOON_KVM_MAGIC) ? 0 : -ENOMEM;
-}
-
-static struct file_system_type balloon_fs = {
-	.name           = "balloon-kvm",
-	.init_fs_context = balloon_init_fs_context,
-	.kill_sb        = kill_anon_super,
-};
-
 #endif /* CONFIG_BALLOON_COMPACTION */
 
 static unsigned long shrink_free_pages(struct virtio_balloon *vb,
@@ -909,19 +890,7 @@ static int virtballoon_probe(struct virtio_device *vdev)
 		goto out_free_vb;
 
 #ifdef CONFIG_BALLOON_COMPACTION
-	balloon_mnt = kern_mount(&balloon_fs);
-	if (IS_ERR(balloon_mnt)) {
-		err = PTR_ERR(balloon_mnt);
-		goto out_del_vqs;
-	}
-
 	vb->vb_dev_info.migratepage = virtballoon_migratepage;
-	vb->vb_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb);
-	if (IS_ERR(vb->vb_dev_info.inode)) {
-		err = PTR_ERR(vb->vb_dev_info.inode);
-		goto out_kern_unmount;
-	}
-	vb->vb_dev_info.inode->i_mapping->a_ops = &balloon_aops;
 #endif
 	if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) {
 		/*
@@ -930,13 +899,13 @@ static int virtballoon_probe(struct virtio_device *vdev)
 		 */
 		if (virtqueue_get_vring_size(vb->free_page_vq) < 2) {
 			err = -ENOSPC;
-			goto out_iput;
+			goto out_del_vqs;
 		}
 		vb->balloon_wq = alloc_workqueue("balloon-wq",
 					WQ_FREEZABLE | WQ_CPU_INTENSIVE, 0);
 		if (!vb->balloon_wq) {
 			err = -ENOMEM;
-			goto out_iput;
+			goto out_del_vqs;
 		}
 		INIT_WORK(&vb->report_free_page_work, report_free_page_func);
 		vb->cmd_id_received_cache = VIRTIO_BALLOON_CMD_ID_STOP;
@@ -1030,13 +999,7 @@ out_unregister_shrinker:
 out_del_balloon_wq:
 	if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT))
 		destroy_workqueue(vb->balloon_wq);
-out_iput:
-#ifdef CONFIG_BALLOON_COMPACTION
-	iput(vb->vb_dev_info.inode);
-out_kern_unmount:
-	kern_unmount(balloon_mnt);
 out_del_vqs:
-#endif
 	vdev->config->del_vqs(vdev);
 out_free_vb:
 	kfree(vb);
@@ -1083,12 +1046,6 @@ static void virtballoon_remove(struct virtio_device *vdev)
 	}
 
 	remove_common(vb);
-#ifdef CONFIG_BALLOON_COMPACTION
-	if (vb->vb_dev_info.inode)
-		iput(vb->vb_dev_info.inode);
-
-	kern_unmount(balloon_mnt);
-#endif
 	kfree(vb);
 }