CAPI: Pin capifs instead of mounting it
Auto-mounting the capifs during module init prevents unloading its
module. Instead, pin the filesystem as long as some NCCI node exists.
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/isdn/capi/capifs.c b/drivers/isdn/capi/capifs.c
index 6ae0edf..51c01ef 100644
--- a/drivers/isdn/capi/capifs.c
+++ b/drivers/isdn/capi/capifs.c
@@ -32,6 +32,7 @@
#define CAPIFS_SUPER_MAGIC (('C'<<8)|'N')
static struct vfsmount *capifs_mnt;
+static int capifs_mnt_count;
static struct {
int setuid;
@@ -140,7 +141,7 @@
.kill_sb = kill_anon_super,
};
-struct dentry *capifs_new_ncci(unsigned int number, dev_t device)
+static struct dentry *new_ncci(unsigned int number, dev_t device)
{
struct super_block *s = capifs_mnt->mnt_sb;
struct dentry *root = s->s_root;
@@ -187,6 +188,20 @@
return dentry;
}
+struct dentry *capifs_new_ncci(unsigned int number, dev_t device)
+{
+ struct dentry *dentry;
+
+ if (simple_pin_fs(&capifs_fs_type, &capifs_mnt, &capifs_mnt_count) < 0)
+ return NULL;
+
+ dentry = new_ncci(number, device);
+ if (!dentry)
+ simple_release_fs(&capifs_mnt, &capifs_mnt_count);
+
+ return dentry;
+}
+
void capifs_free_ncci(struct dentry *dentry)
{
struct dentry *root = capifs_mnt->mnt_sb->s_root;
@@ -206,6 +221,8 @@
dput(dentry);
mutex_unlock(&root->d_inode->i_mutex);
+
+ simple_release_fs(&capifs_mnt, &capifs_mnt_count);
}
static int __init capifs_init(void)
@@ -222,13 +239,6 @@
strcpy(rev, "1.0");
err = register_filesystem(&capifs_fs_type);
- if (!err) {
- capifs_mnt = kern_mount(&capifs_fs_type);
- if (IS_ERR(capifs_mnt)) {
- err = PTR_ERR(capifs_mnt);
- unregister_filesystem(&capifs_fs_type);
- }
- }
if (!err)
printk(KERN_NOTICE "capifs: Rev %s\n", rev);
return err;
@@ -237,7 +247,6 @@
static void __exit capifs_exit(void)
{
unregister_filesystem(&capifs_fs_type);
- mntput(capifs_mnt);
}
EXPORT_SYMBOL(capifs_new_ncci);