Subject: [PATCH 8/9] z3fold: remove the z3fold file system

From: Christoph Hellwig <[email-masked]>
Date: Tue, 9 Mar 2021 16:53:47 +0100

Just use the generic anon_inode file system.

Signed-off-by: Christoph Hellwig <[email-masked]>
---
 mm/z3fold.c | 38 ++------------------------------------
 1 file changed, 2 insertions(+), 36 deletions(-)

diff --git a/mm/z3fold.c b/mm/z3fold.c
index e7cd9298b221f5..e0749a3d8987de 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -23,6 +23,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/anon_inodes.h>
 #include <linux/atomic.h>
 #include <linux/sched.h>
 #include <linux/cpumask.h>
@@ -345,38 +346,10 @@ static inline void free_handle(unsigned long handle, struct z3fold_header *zhdr)
 	}
 }
 
-static int z3fold_init_fs_context(struct fs_context *fc)
-{
-	return init_pseudo(fc, Z3FOLD_MAGIC) ? 0 : -ENOMEM;
-}
-
-static struct file_system_type z3fold_fs = {
-	.name		= "z3fold",
-	.init_fs_context = z3fold_init_fs_context,
-	.kill_sb	= kill_anon_super,
-};
-
-static struct vfsmount *z3fold_mnt;
-static int z3fold_mount(void)
-{
-	int ret = 0;
-
-	z3fold_mnt = kern_mount(&z3fold_fs);
-	if (IS_ERR(z3fold_mnt))
-		ret = PTR_ERR(z3fold_mnt);
-
-	return ret;
-}
-
-static void z3fold_unmount(void)
-{
-	kern_unmount(z3fold_mnt);
-}
-
 static const struct address_space_operations z3fold_aops;
 static int z3fold_register_migration(struct z3fold_pool *pool)
 {
-	pool->inode = alloc_anon_inode_sb(z3fold_mnt->mnt_sb);
+	pool->inode = alloc_anon_inode();
 	if (IS_ERR(pool->inode)) {
 		pool->inode = NULL;
 		return 1;
@@ -1787,22 +1760,15 @@ MODULE_ALIAS("zpool-z3fold");
 
 static int __init init_z3fold(void)
 {
-	int ret;
-
 	/* Make sure the z3fold header is not larger than the page size */
 	BUILD_BUG_ON(ZHDR_SIZE_ALIGNED > PAGE_SIZE);
-	ret = z3fold_mount();
-	if (ret)
-		return ret;
 
 	zpool_register_driver(&z3fold_zpool_driver);
-
 	return 0;
 }
 
 static void __exit exit_z3fold(void)
 {
-	z3fold_unmount();
 	zpool_unregister_driver(&z3fold_zpool_driver);
 }
 
-- 
2.30.1