[PATCH 22/39] convert ibmasmfs

[Al Viro]

static contents for each "service processor", whatever the fuck it is.
Congruent subdirectories of root, created at mount time, taken out
by kill_litter_super().  All dentries created with d_alloc_name() and are
left pinned.  The odd part is that the list of service providers is
assumed to be unchanging - no locking, nothing to handle removals or
extra elements added later on.

... and it's a PCI device.  If you ever tell it to remove an instance,
you are fucked - it doesn't bother with removing its directory from filesystem,
it has a strange check that presumably wanted to be a check for removed
devices, but it had never been fleshed out.

Anyway, d_add() -> d_make_persistent()+dput() in ibmasmfs_create_dir() and
ibmasmfs_create_file(), and make the latter return int - no need to even
borrow that dentry, callers completely ignore it.

Signed-off-by: Al Viro <viro at zeniv.linux.org.uk>
---
 drivers/misc/ibmasm/ibmasmfs.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/misc/ibmasm/ibmasmfs.c b/drivers/misc/ibmasm/ibmasmfs.c
index c44de892a61e..785ce294f4b9 100644
--- a/drivers/misc/ibmasm/ibmasmfs.c
+++ b/drivers/misc/ibmasm/ibmasmfs.c
@@ -103,7 +103,7 @@ static struct file_system_type ibmasmfs_type = {
 	.owner          = THIS_MODULE,
 	.name           = "ibmasmfs",
 	.init_fs_context = ibmasmfs_init_fs_context,
-	.kill_sb        = kill_litter_super,
+	.kill_sb        = kill_anon_super,
 };
 MODULE_ALIAS_FS("ibmasmfs");
 
@@ -144,7 +144,7 @@ static struct inode *ibmasmfs_make_inode(struct super_block *sb, int mode)
 	return ret;
 }
 
-static struct dentry *ibmasmfs_create_file(struct dentry *parent,
+static int ibmasmfs_create_file(struct dentry *parent,
 			const char *name,
 			const struct file_operations *fops,
 			void *data,
@@ -155,19 +155,20 @@ static struct dentry *ibmasmfs_create_file(struct dentry *parent,
 
 	dentry = d_alloc_name(parent, name);
 	if (!dentry)
-		return NULL;
+		return -ENOMEM;
 
 	inode = ibmasmfs_make_inode(parent->d_sb, S_IFREG | mode);
 	if (!inode) {
 		dput(dentry);
-		return NULL;
+		return -ENOMEM;
 	}
 
 	inode->i_fop = fops;
 	inode->i_private = data;
 
-	d_add(dentry, inode);
-	return dentry;
+	d_make_persistent(dentry, inode);
+	dput(dentry);
+	return 0;
 }
 
 static struct dentry *ibmasmfs_create_dir(struct dentry *parent,
@@ -189,8 +190,9 @@ static struct dentry *ibmasmfs_create_dir(struct dentry *parent,
 	inode->i_op = &simple_dir_inode_operations;
 	inode->i_fop = ibmasmfs_dir_ops;
 
-	d_add(dentry, inode);
-	return dentry;
+	d_make_persistent(dentry, inode);
+	dput(dentry);
+	return dentry; // borrowed
 }
 
 int ibmasmfs_register(void)
-- 
2.47.3