[PATCH] introduce __blkdev_driver_ioctl()

Analog of blkdev_driver_ioctl() with sane arguments.  For
now uses fake struct file, by the end of the series it won't
and blkdev_driver_ioctl() will become a wrapper around it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

5 files changed, 39 insertions, 19 deletions

diff --git a/block/ioctl.c b/block/ioctl.c
index 38bee321e1fa..9a26ace6d042 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -283,6 +283,37 @@ int blkdev_driver_ioctl(struct inode *inode, struct file *file,
 }
 EXPORT_SYMBOL_GPL(blkdev_driver_ioctl);
 
+int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
+                        unsigned cmd, unsigned long arg)
+{
+        struct gendisk *disk = bdev->bd_disk;
+        int ret;
+        /* you bet it'll go away by the end of patch series */
+        struct file fake_file = {};
+        struct dentry fake_dentry = {};
+        fake_file.f_mode = mode;
+        fake_file.f_path.dentry = &fake_dentry;
+        fake_dentry.d_inode = bdev->bd_inode;
+
+        if (disk->fops->unlocked_ioctl)
+                return disk->fops->unlocked_ioctl(&fake_file, cmd, arg);
+
+        if (disk->fops->ioctl) {
+                lock_kernel();
+                ret = disk->fops->ioctl(bdev->bd_inode, &fake_file, cmd, arg);
+                unlock_kernel();
+                return ret;
+        }
+
+        return -ENOTTY;
+}
+/*
+ * For the record: _GPL here is only because somebody decided to slap it
+ * on the previous export.  Sheer idiocy, since it wasn't copyrightable
+ * at all and could be open-coded without any exports by anybody who cares.
+ */
+EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
+
 /*
  * always keep this in sync with compat_blkdev_ioctl() and
  * compat_blkdev_locked_ioctl()
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index bdd49abcb546..a0ba4023953b 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2819,8 +2819,8 @@ static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u
         case CDROM_LAST_WRITTEN:
         case CDROM_SEND_PACKET:
         case SCSI_IOCTL_SEND_COMMAND:
-                return blkdev_driver_ioctl(pd->bdev->bd_inode, pd->bdev->bd_disk,
-                                        file, cmd, arg);
+                return __blkdev_driver_ioctl(pd->bdev, file ? file->f_mode : 0,
+                                        cmd, arg);
 
         default:
                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index fa358385eed3..373442b1e98f 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -114,15 +114,7 @@ static int linear_ioctl(struct dm_target *ti, unsigned int cmd,
                         unsigned long arg)
 {
         struct linear_c *lc = (struct linear_c *) ti->private;
-        struct block_device *bdev = lc->dev->bdev;
-        struct file fake_file = {};
-        struct dentry fake_dentry = {};
-
-        fake_file.f_mode = lc->dev->mode;
-        fake_file.f_path.dentry = &fake_dentry;
-        fake_dentry.d_inode = bdev->bd_inode;
-
-        return blkdev_driver_ioctl(bdev->bd_inode, &fake_file, bdev->bd_disk, cmd, arg);
+        return __blkdev_driver_ioctl(lc->dev->bdev, lc->dev->mode, cmd, arg);
 }
 
 static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index c681d5e5f45c..d85c65a46433 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1400,13 +1400,10 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 {
         struct multipath *m = (struct multipath *) ti->private;
         struct block_device *bdev = NULL;
+        fmode_t mode = 0;
         unsigned long flags;
-        struct file fake_file = {};
-        struct dentry fake_dentry = {};
         int r = 0;
 
-        fake_file.f_path.dentry = &fake_dentry;
-
         spin_lock_irqsave(&m->lock, flags);
 
         if (!m->current_pgpath)
@@ -1414,8 +1411,7 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 
         if (m->current_pgpath) {
                 bdev = m->current_pgpath->path.dev->bdev;
-                fake_dentry.d_inode = bdev->bd_inode;
-                fake_file.f_mode = m->current_pgpath->path.dev->mode;
+                mode = m->current_pgpath->path.dev->mode;
         }
 
         if (m->queue_io)
@@ -1425,8 +1421,7 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 
         spin_unlock_irqrestore(&m->lock, flags);
 
-        return r ? : blkdev_driver_ioctl(bdev->bd_inode, &fake_file,
-                                         bdev->bd_disk, cmd, arg);
+        return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
 }
 
 /*-----------------------------------------------------------------
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 48ec8862a11a..2bad616b9949 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1074,6 +1074,8 @@ struct block_device_operations {
         struct module *owner;
 };
 
+extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
+                                 unsigned long);
 #else /* CONFIG_BLOCK */
 /*
  * stubs for when the block layer is configured out