1/*
2 * sd_dif.c - SCSI Data Integrity Field
3 *
4 * Copyright (C) 2007, 2008 Oracle Corporation
5 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; see the file COPYING. If not, write to
18 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
19 * USA.
20 *
21 */
22
23#include <linux/blkdev.h>
24#include <linux/t10-pi.h>
25
26#include <scsi/scsi.h>
27#include <scsi/scsi_cmnd.h>
28#include <scsi/scsi_dbg.h>
29#include <scsi/scsi_device.h>
30#include <scsi/scsi_driver.h>
31#include <scsi/scsi_eh.h>
32#include <scsi/scsi_host.h>
33#include <scsi/scsi_ioctl.h>
34#include <scsi/scsicam.h>
35
36#include "sd.h"
37
38/*
39 * Configure exchange of protection information between OS and HBA.
40 */
41void sd_dif_config_host(struct scsi_disk *sdkp)
42{
43 struct scsi_device *sdp = sdkp->device;
44 struct gendisk *disk = sdkp->disk;
45 u8 type = sdkp->protection_type;
46 struct blk_integrity bi;
47 int dif, dix;
48
49 dif = scsi_host_dif_capable(sdp->host, type);
50 dix = scsi_host_dix_capable(sdp->host, type);
51
52 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
53 dif = 0; dix = 1;
54 }
55
56 if (!dix)
57 return;
58
59 memset(&bi, 0, sizeof(bi));
60
61 /* Enable DMA of protection information */
62 if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) {
63 if (type == T10_PI_TYPE3_PROTECTION)
64 bi.profile = &t10_pi_type3_ip;
65 else
66 bi.profile = &t10_pi_type1_ip;
67
68 bi.flags |= BLK_INTEGRITY_IP_CHECKSUM;
69 } else
70 if (type == T10_PI_TYPE3_PROTECTION)
71 bi.profile = &t10_pi_type3_crc;
72 else
73 bi.profile = &t10_pi_type1_crc;
74
75 bi.tuple_size = sizeof(struct t10_pi_tuple);
76 sd_printk(KERN_NOTICE, sdkp,
77 "Enabling DIX %s protection\n", bi.profile->name);
78
79 if (dif && type) {
80 bi.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
81
82 if (!sdkp->ATO)
83 goto out;
84
85 if (type == T10_PI_TYPE3_PROTECTION)
86 bi.tag_size = sizeof(u16) + sizeof(u32);
87 else
88 bi.tag_size = sizeof(u16);
89
90 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
91 bi.tag_size);
92 }
93
94out:
95 blk_integrity_register(disk, &bi);
96}
97
98