linux.git/drivers/scsi/sd.c, branch v3.19

sd: Fix max transfer length for 4k disks

2015-02-02T12:46:29+00:00

The following patch fixes an issue observed with 4k sector disks
where the max_hw_sectors attribute was getting set too large in
sd_revalidate_disk. Since sdkp->max_xfer_blocks is in units
of SCSI logical blocks and queue_max_hw_sectors is in units of
512 byte blocks, on a 4k sector disk, every time we went through
sd_revalidate_disk, we were taking the current value of
queue_max_hw_sectors and increasing it by a factor of 8. Fix
this by only shifting sdkp->max_xfer_blocks.

Cc: stable@vger.kernel.org
Signed-off-by: Brian King 
Reviewed-by: Paolo Bonzini 
Reviewed-by: Martin K. Petersen 
Signed-off-by: Christoph Hellwig

sd: tweak discard heuristics to work around QEMU SCSI issue

2014-12-30T12:30:38+00:00

7985090aa020 changed the discard heuristics to give preference to the
WRITE SAME commands that (unlike UNMAP) guarantee deterministic results.

Ming Lei discovered that QEMU SCSI's WRITE SAME implementation
internally relied on limits that were only communicated for the UNMAP
case. And therefore discard commands backed by WRITE SAME would fail.

Tweak the heuristics so we still pick UNMAP in the LBPRZ=0 case and only
prefer the WRITE SAME variants if the device has the LBPRZ flag set.

Reported-by: Ming Lei 
Tested-by: Ming Lei 
Signed-off-by: Martin K. Petersen 
Acked-by: Paolo Bonzini 
Signed-off-by: Christoph Hellwig

scsi: rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16

2014-11-24T19:01:40+00:00

SPC-3 defines SERVICE ACTION IN(12) and SERVICE ACTION IN(16).
So rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16 to be
consistent with SPC and to allow for better distinction.

Signed-off-by: Hannes Reinecke 
Tested-by: Robert Elliott 
Reviewed-by: Robert Elliott 
Signed-off-by: Christoph Hellwig

scsi: remove scsi_driver owner field

2014-11-24T19:01:28+00:00

The driver core driver structure has grown an owner field and now
requires it to be set for all modular drivers.  Set it up for
all scsi_driver instances and get rid of the now superflous
scsi_driver owner field.

Signed-off-by: Christoph Hellwig 
Reported-by: Shane M Seymour 
Reviewed-by: Ewan D. Milne

scsi: stop passing a gfp_mask argument down the command setup path

2014-11-24T18:56:55+00:00

There is no reason for ULDs to pass in a flag on how to allocate the S/G
lists.  While we don't need GFP_ATOMIC for the blk-mq case because we
don't hold locks, that decision can be made way down the chain without
having to pass a pointless gfp_mask argument.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Bart Van Assche 
Reviewed-by: Hannes Reinecke

sd: disable discard_zeroes_data for UNMAP

2014-11-12T10:19:14+00:00

The T10 SBC UNMAP command does not provide any hard guarantees that
blocks will return zeroes on a subsequent READ. This is due to the fact
that the device server is free to silently ignore all or parts of the
request.

The only way to ensure that a block consistently returns zeroes after
being unmapped is to use WRITE SAME with the UNMAP bit set. Should the
device be unable to unmap one or more blocks described by the command it
is required to manually write zeroes to them.

Until now we have preferred UNMAP over the WRITE SAME variants to
accommodate thinly provisioned devices that predated the final SBC-3
spec. This patch changes the heuristic so that we favor WRITE SAME(16)
or (10) over UNMAP if these commands are marked as supported in the
Logical Block Provisioning VPD page.

The patch also disables discard_zeroes_data for devices operating in
UNMAP mode.

Signed-off-by: Martin K. Petersen 
Reviewed-by: Paolo Bonzini 
Signed-off-by: Christoph Hellwig

sd: fix up ->compat_ioctl

2014-11-12T10:16:11+00:00

No need to verify the passthrough ioctls, the real handler will
take care of that.  Also make sure not to block for resets on
O_NONBLOCK fds.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Martin K. Petersen 
Reviewed-by: Hannes Reinecke

scsi: split scsi_nonblockable_ioctl

2014-11-12T10:16:11+00:00

The calling conventions for this function are bad as it could return
-ENODEV both for a device not currently online and a not recognized ioctl.

Add a new scsi_ioctl_block_when_processing_errors function that wraps
scsi_block_when_processing_errors with the a special case for the
SG_SCSI_RESET ioctl command, and handle the SG_SCSI_RESET case itself
in scsi_ioctl.  All callers of scsi_ioctl now must call the above helper
to check for the EH state, so that the ioctl handler itself doesn't
have to.

Reported-by: Robert Elliott 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Martin K. Petersen 
Reviewed-by: Hannes Reinecke

scsi: remove scsi_show_result()

2014-11-12T10:16:05+00:00

Open-code scsi_print_result in sd.c, and cleanup logging to
not print duplicate informations.
Also remove the call to scsi_show_result() in ufshcd.c
to be consistent with other callers of scsi_execute().

With that we can remove scsi_show_result in constants.c

Signed-off-by: Hannes Reinecke 
Reviewed-by: Robert Elliott 
Signed-off-by: Christoph Hellwig

scsi: use sdev as argument for sense code printing

2014-11-12T10:15:58+00:00

We should be using the standard dev_printk() variants for
sense code printing.

[hch: remove __scsi_print_sense call in xen-scsiback, Acked by Juergen]
[hch: folded bracing fix from Dan Carpenter]
Signed-off-by: Hannes Reinecke 
Reviewed-by: Robert Elliott 
Signed-off-by: Christoph Hellwig