Add /dev/btrfs-control for device scanning ioctls
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 4423a91..67ed216 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -36,6 +36,7 @@
#include <linux/parser.h>
#include <linux/ctype.h>
#include <linux/namei.h>
+#include <linux/miscdevice.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
@@ -444,6 +445,13 @@
return 0;
}
+static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ printk("btrfs control ioctl %d\n", cmd);
+ return 0;
+}
+
static struct file_system_type btrfs_fs_type = {
.owner = THIS_MODULE,
.name = "btrfs",
@@ -451,6 +459,7 @@
.kill_sb = kill_block_super,
.fs_flags = FS_REQUIRES_DEV,
};
+
static void btrfs_write_super_lockfs(struct super_block *sb)
{
struct btrfs_root *root = btrfs_sb(sb);
@@ -482,6 +491,30 @@
.write_super_lockfs = btrfs_write_super_lockfs,
.unlockfs = btrfs_unlockfs,
};
+
+static const struct file_operations btrfs_ctl_fops = {
+ .unlocked_ioctl = btrfs_control_ioctl,
+ .compat_ioctl = btrfs_control_ioctl,
+ .owner = THIS_MODULE,
+};
+
+static struct miscdevice btrfs_misc = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "btrfs-control",
+ .fops = &btrfs_ctl_fops
+};
+
+static int btrfs_interface_init(void)
+{
+ return misc_register(&btrfs_misc);
+}
+
+void btrfs_interface_exit(void)
+{
+ if (misc_deregister(&btrfs_misc) < 0)
+ printk("misc_deregister failed for control device");
+}
+
static int __init init_btrfs_fs(void)
{
int err;
@@ -503,11 +536,16 @@
if (err)
goto free_extent_io;
- err = register_filesystem(&btrfs_fs_type);
+ err = btrfs_interface_init();
if (err)
goto free_extent_map;
+ err = register_filesystem(&btrfs_fs_type);
+ if (err)
+ goto unregister_ioctl;
return 0;
+unregister_ioctl:
+ btrfs_interface_exit();
free_extent_map:
extent_map_exit();
free_extent_io:
@@ -526,6 +564,7 @@
btrfs_destroy_cachep();
extent_map_exit();
extent_io_exit();
+ btrfs_interface_exit();
unregister_filesystem(&btrfs_fs_type);
btrfs_exit_sysfs();
}