dm: refactor ioctl handling
This moves the call to blkdev_ioctl and the argument checking to DM core
code, and only leaves a callout to find the block device to operate on
in the targets. This simplifies the code and allows us to pass through
ioctl-like command using other methods in the next patch.
Also split out a helper around calling the prepare_ioctl method that
will be reused for persistent reservation handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
diff --git a/drivers/md/dm-switch.c b/drivers/md/dm-switch.c
index 50fca46..b128575 100644
--- a/drivers/md/dm-switch.c
+++ b/drivers/md/dm-switch.c
@@ -511,27 +511,24 @@
*
* Passthrough all ioctls to the path for sector 0
*/
-static int switch_ioctl(struct dm_target *ti, unsigned cmd,
- unsigned long arg)
+static int switch_prepare_ioctl(struct dm_target *ti,
+ struct block_device **bdev, fmode_t *mode)
{
struct switch_ctx *sctx = ti->private;
- struct block_device *bdev;
- fmode_t mode;
unsigned path_nr;
- int r = 0;
path_nr = switch_get_path_nr(sctx, 0);
- bdev = sctx->path_list[path_nr].dmdev->bdev;
- mode = sctx->path_list[path_nr].dmdev->mode;
+ *bdev = sctx->path_list[path_nr].dmdev->bdev;
+ *mode = sctx->path_list[path_nr].dmdev->mode;
/*
* Only pass ioctls through if the device sizes match exactly.
*/
- if (ti->len + sctx->path_list[path_nr].start != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT)
- r = scsi_verify_blk_ioctl(NULL, cmd);
-
- return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+ if (ti->len + sctx->path_list[path_nr].start !=
+ i_size_read((*bdev)->bd_inode) >> SECTOR_SHIFT)
+ return 1;
+ return 0;
}
static int switch_iterate_devices(struct dm_target *ti,
@@ -560,7 +557,7 @@
.map = switch_map,
.message = switch_message,
.status = switch_status,
- .ioctl = switch_ioctl,
+ .prepare_ioctl = switch_prepare_ioctl,
.iterate_devices = switch_iterate_devices,
};