dm: do not forward ioctls from logical volumes to the underlying device

A logical volume can map to just part of underlying physical volume.
In this case, it must be treated like a partition.

Based on a patch from Alasdair G Kergon.

Cc: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paolo Bonzini 2012-01-12 16:01:29 +01:00 committed by Linus Torvalds
parent 0bfc96cb77
commit ec8013bedd
3 changed files with 27 additions and 2 deletions

View File

@ -368,8 +368,17 @@ static int flakey_status(struct dm_target *ti, status_type_t type,
static int flakey_ioctl(struct dm_target *ti, unsigned int cmd, unsigned long arg)
{
struct flakey_c *fc = ti->private;
struct dm_dev *dev = fc->dev;
int r = 0;
return __blkdev_driver_ioctl(fc->dev->bdev, fc->dev->mode, cmd, arg);
/*
* Only pass ioctls through if the device sizes match exactly.
*/
if (fc->start ||
ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT)
r = scsi_verify_blk_ioctl(NULL, cmd);
return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
}
static int flakey_merge(struct dm_target *ti, struct bvec_merge_data *bvm,

View File

@ -116,7 +116,17 @@ static int linear_ioctl(struct dm_target *ti, unsigned int cmd,
unsigned long arg)
{
struct linear_c *lc = (struct linear_c *) ti->private;
return __blkdev_driver_ioctl(lc->dev->bdev, lc->dev->mode, cmd, arg);
struct dm_dev *dev = lc->dev;
int r = 0;
/*
* Only pass ioctls through if the device sizes match exactly.
*/
if (lc->start ||
ti->len != i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT)
r = scsi_verify_blk_ioctl(NULL, cmd);
return r ? : __blkdev_driver_ioctl(dev->bdev, dev->mode, cmd, arg);
}
static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,

View File

@ -1520,6 +1520,12 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
spin_unlock_irqrestore(&m->lock, flags);
/*
* Only pass ioctls through if the device sizes match exactly.
*/
if (!r && ti->len != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT)
r = scsi_verify_blk_ioctl(NULL, cmd);
return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}