This patch adds support for DIX and DIF in scsi_debug.  A separate
buffer is allocated for the protection information.

 - The dix parameter indicates whether the controller supports DIX
   (protection information DMA)

 - The dif parameter indicates whether the simulated storage device
   supports DIF

 - The guard parameter switches between T10 CRC(0) and IP checksum(1)

 - The ato parameter indicates whether the application tag is owned by
   the disk(0) or the OS(1)

 - DIF and DIX errors can be triggered using the scsi_debug_opts mask

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[jejb: limit ioctl to returning 20 characters to avoid overrun
       on long device names and add a few more conversions]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[jejb: fixed up a ton of missed conversions.

 All of you are on notice this has happened, driver trees will now
 need to be rebased]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: SCSI List <linux-scsi@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

Add support for VPD page b1 to scsi_debug

SCSI VPD page b1 reports the nominal rotation speed of the device.
Since scsi_debug is ram-based, claim to be a non-rotating medium.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

Make scsi_debug sector size configurable at load time instead of being
a #define.  Handy for testing 4KB sectors.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

This patch removes function declarations with moving some
functions. This cleans up them a bit to silence checkpatch.pl. There
is no functional change.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

Currently, the maximum amount of RAM that scsi_debug can allocate is
4GB. This patch increases it to 2TB; scsi_debug can allocates 2TB
memory and export it as if it were 2TB scsi disk.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

resp_read and resp_write performs READ_* and WRITE_* commands
respectively. This sweeps up the similar code in them.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

sdebug_capacity is calculated at five different places. This add a
helper function to calculate sdebug_capacity to sweep up the
duplicatated code.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Douglas Gilbert <dougg@torque.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>