On 09.03.21 16:53, Christoph Hellwig wrote:

Just use the generic anon_inode file system.

Signed-off-by: Christoph Hellwig hch@lst.de

arch/powerpc/platforms/pseries/cmm.c | 27 ++------------------------- 1 file changed, 2 insertions(+), 25 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/cmm.c b/arch/powerpc/platforms/pseries/cmm.c index 6d36b858b14df1..9d07e6bea7126c 100644 --- a/arch/powerpc/platforms/pseries/cmm.c +++ b/arch/powerpc/platforms/pseries/cmm.c @@ -6,6 +6,7 @@

• Author(s): Brian King (brking@linux.vnet.ibm.com),

*/

+#include <linux/anon_inodes.h> #include <linux/ctype.h> #include <linux/delay.h> #include <linux/errno.h> @@ -502,19 +503,6 @@ static struct notifier_block cmm_mem_nb = { };

#ifdef CONFIG_BALLOON_COMPACTION -static struct vfsmount *balloon_mnt;

-static int cmm_init_fs_context(struct fs_context *fc) -{

• return init_pseudo(fc, PPC_CMM_MAGIC) ? 0 : -ENOMEM;

-}

-static struct file_system_type balloon_fs = {

• .name = "ppc-cmm",
• .init_fs_context = cmm_init_fs_context,
• .kill_sb = kill_anon_super,

-};

• static int cmm_migratepage(struct balloon_dev_info *b_dev_info, struct page *newpage, struct page *page, enum migrate_mode mode)

@@ -573,19 +561,10 @@ static int cmm_balloon_compaction_init(void) balloon_devinfo_init(&b_dev_info); b_dev_info.migratepage = cmm_migratepage;

• balloon_mnt = kern_mount(&balloon_fs);
• if (IS_ERR(balloon_mnt)) {

• rc = PTR_ERR(balloon_mnt);
  

• balloon_mnt = NULL;
  

• return rc;
  

• }
• b_dev_info.inode = alloc_anon_inode_sb(balloon_mnt->mnt_sb);

• b_dev_info.inode = alloc_anon_inode(); if (IS_ERR(b_dev_info.inode)) { rc = PTR_ERR(b_dev_info.inode); b_dev_info.inode = NULL;

• kern_unmount(balloon_mnt);
  

• balloon_mnt = NULL;
  

  return rc; }

@@ -597,8 +576,6 @@ static void cmm_balloon_compaction_deinit(void) if (b_dev_info.inode) iput(b_dev_info.inode); b_dev_info.inode = NULL;

• kern_unmount(balloon_mnt);
• balloon_mnt = NULL; } #else /* CONFIG_BALLOON_COMPACTION */ static int cmm_balloon_compaction_init(void)

I always wondered why that was necessary after all (with my limited fs knowledge :) ).

a) I assume you want to remove PPC_CMM_MAGIC from include/uapi/linux/magic.h as well?

b) Do we still need #include <linux/magic.h>, #include <linux/mount.h> and #include <linux/pseudo_fs.h>?

Apart from that looks much cleaner.