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 */
27void sd_dif_config_host(struct scsi_disk *sdkp)
28{
29 struct scsi_device *sdp = sdkp->device;
30 struct gendisk *disk = sdkp->disk;
31 u8 type = sdkp->protection_type;
32 struct blk_integrity bi;
33 int dif, dix;
34
35 dif = scsi_host_dif_capable(shost: sdp->host, target_type: type);
36 dix = scsi_host_dix_capable(shost: sdp->host, target_type: type);
37
38 if (!dix && scsi_host_dix_capable(shost: sdp->host, target_type: 0)) {
39 dif = 0; dix = 1;
40 }
41
42 if (!dix) {
43 blk_integrity_unregister(disk);
44 return;
45 }
46
47 memset(&bi, 0, sizeof(bi));
48
49 /* Enable DMA of protection information */
50 if (scsi_host_get_guard(shost: sdkp->device->host) & SHOST_DIX_GUARD_IP) {
51 if (type == T10_PI_TYPE3_PROTECTION)
52 bi.profile = &t10_pi_type3_ip;
53 else
54 bi.profile = &t10_pi_type1_ip;
55
56 bi.flags |= BLK_INTEGRITY_IP_CHECKSUM;
57 } else
58 if (type == T10_PI_TYPE3_PROTECTION)
59 bi.profile = &t10_pi_type3_crc;
60 else
61 bi.profile = &t10_pi_type1_crc;
62
63 bi.tuple_size = sizeof(struct t10_pi_tuple);
64
65 if (dif && type) {
66 bi.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
67
68 if (!sdkp->ATO)
69 goto out;
70
71 if (type == T10_PI_TYPE3_PROTECTION)
72 bi.tag_size = sizeof(u16) + sizeof(u32);
73 else
74 bi.tag_size = sizeof(u16);
75 }
76
77 sd_first_printk(KERN_NOTICE, sdkp,
78 "Enabling DIX %s, application tag size %u bytes\n",
79 bi.profile->name, bi.tag_size);
80out:
81 blk_integrity_register(disk, &bi);
82}
83
84

source code of linux/drivers/scsi/sd_dif.c