Andrew Morton wrote:
On Wed, 21 Jun 2006 20:31:21 +0100
Alasdair G Kergon <[email protected]> wrote:
From: Milan Broz <[email protected]>
Extend the core device-mapper infrastructure to accept arbitrary ioctls
on a mapped device provided that it has exactly one target and it is
capable of supporting ioctls.
I don't understand that. We're taking an ioctl against a dm device and
we're passing it through to an underlying device? Or something else?
Solving this situation: logical volume (say /dev/mapper/lv1) mapped in dm
to single device (/dev/sda):
If there is need to send ioctl you must know that /dev/mapper/lv1
is mapped to /dev/sda (and use /dev/sda for ioctl).
This is dm work - so send ioctl to /dev/mapper/lv1 directly
and let dm decide what to do.
This is supported only for single mapping. If there are more than one target
it will return -ENOTTY.
[We can't use unlocked_ioctl because we need 'inode': 'file' might be NULL.
Is it worth changing this?]
It _should_ be possible to use unlocked_ioctl() - unlocked_ioctl() would be
pretty useless if someone was passing it a NULL file*. More details?
yes,
(I prefer change block code to not pass NULL and use unlocked_ioctl,
- Alasdair ?)
see
drivers/char/raw.c:
126: return blkdev_ioctl(bdev->bd_inode, *NULL*, command, arg);
and block/ioctl.c: [file = NULL here]
206: if (disk->fops->unlocked_ioctl)
207: return disk->fops->unlocked_ioctl(*file*, cmd, arg);
--
Milan Broz
[email protected]
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
