drivers/scsi/sd_dif.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * sd_dif.c - SCSI Data Integrity Field
   4  *
   5  * Copyright (C) 2007, 2008 Oracle Corporation
   6  * Written by: Martin K. Petersen <martin.petersen@oracle.com>
   7  */
   8
   9 #include <linux/blk-integrity.h>
  10 #include <linux/t10-pi.h>
  11
  12 #include <scsi/scsi.h>
  13 #include <scsi/scsi_cmnd.h>
  14 #include <scsi/scsi_dbg.h>
  15 #include <scsi/scsi_device.h>
  16 #include <scsi/scsi_driver.h>
  17 #include <scsi/scsi_eh.h>
  18 #include <scsi/scsi_host.h>
  19 #include <scsi/scsi_ioctl.h>
  20 #include <scsi/scsicam.h>
  21
  22 #include "sd.h"
  23
  24 /*
  25  * Configure exchange of protection information between OS and HBA.
  26  */
  27 void sd_dif_config_host(struct scsi_disk *sdkp, struct queue_limits *lim)
  28 {
  29         struct scsi_device *sdp = sdkp->device;
  30         u8 type = sdkp->protection_type;
  31         struct blk_integrity *bi = &lim->integrity;
  32         int dif, dix;
  33
  34         memset(bi, 0, sizeof(*bi));
  35
  36         dif = scsi_host_dif_capable(sdp->host, type);
  37         dix = scsi_host_dix_capable(sdp->host, type);
  38
  39         if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
  40                 dif = 0; dix = 1;
  41         }
  42
  43         if (!dix)
  44                 return;
  45
  46         /* Enable DMA of protection information */
  47         if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
  48                 bi->csum_type = BLK_INTEGRITY_CSUM_IP;
  49         else
  50                 bi->csum_type = BLK_INTEGRITY_CSUM_CRC;
  51
  52         if (type != T10_PI_TYPE3_PROTECTION)
  53                 bi->flags |= BLK_INTEGRITY_REF_TAG;
  54
  55         bi->tuple_size = sizeof(struct t10_pi_tuple);
  56
  57         if (dif && type) {
  58                 bi->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
  59
  60                 if (!sdkp->ATO)
  61                         return;
  62
  63                 if (type == T10_PI_TYPE3_PROTECTION)
  64                         bi->tag_size = sizeof(u16) + sizeof(u32);
  65                 else
  66                         bi->tag_size = sizeof(u16);
  67         }
  68
  69         sd_first_printk(KERN_NOTICE, sdkp,
  70                         "Enabling DIX %s, application tag size %u bytes\n",
  71                         blk_integrity_profile_name(bi), bi->tag_size);
  72 }