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linux/drivers/scsi/sd_dif.c
Christoph Hellwig c6e56cf6b2 block: move integrity information into queue_limits
Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.

Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired.  However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED().  Given that tiny size of it that seems like
a worthwhile trade off.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-14 10:20:07 -06:00

73 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* sd_dif.c - SCSI Data Integrity Field
*
* Copyright (C) 2007, 2008 Oracle Corporation
* Written by: Martin K. Petersen <martin.petersen@oracle.com>
*/
#include <linux/blk-integrity.h>
#include <linux/t10-pi.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h>
#include "sd.h"
/*
* Configure exchange of protection information between OS and HBA.
*/
void sd_dif_config_host(struct scsi_disk *sdkp, struct queue_limits *lim)
{
struct scsi_device *sdp = sdkp->device;
u8 type = sdkp->protection_type;
struct blk_integrity *bi = &lim->integrity;
int dif, dix;
memset(bi, 0, sizeof(*bi));
dif = scsi_host_dif_capable(sdp->host, type);
dix = scsi_host_dix_capable(sdp->host, type);
if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
dif = 0; dix = 1;
}
if (!dix)
return;
/* Enable DMA of protection information */
if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
bi->csum_type = BLK_INTEGRITY_CSUM_IP;
else
bi->csum_type = BLK_INTEGRITY_CSUM_CRC;
if (type != T10_PI_TYPE3_PROTECTION)
bi->flags |= BLK_INTEGRITY_REF_TAG;
bi->tuple_size = sizeof(struct t10_pi_tuple);
if (dif && type) {
bi->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
if (!sdkp->ATO)
return;
if (type == T10_PI_TYPE3_PROTECTION)
bi->tag_size = sizeof(u16) + sizeof(u32);
else
bi->tag_size = sizeof(u16);
}
sd_first_printk(KERN_NOTICE, sdkp,
"Enabling DIX %s, application tag size %u bytes\n",
blk_integrity_profile_name(bi), bi->tag_size);
}