blob: 987bf392c336181036f19debf282be2c2f9d1ffa [file] [log] [blame]
Martin K. Petersenaf55ff62008-07-17 04:28:35 -04001/*
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>
Martin K. Petersen2341c2f2014-09-26 19:20:07 -040024#include <linux/t10-pi.h>
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040025
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
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040036#include "sd.h"
37
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040038/*
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;
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040046 struct blk_integrity bi;
Martin K. Petersen9e066882008-09-19 18:47:21 -040047 int dif, dix;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040048
Martin K. Petersen9e066882008-09-19 18:47:21 -040049 dif = scsi_host_dif_capable(sdp->host, type);
50 dix = scsi_host_dix_capable(sdp->host, type);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040051
Martin K. Petersen9e066882008-09-19 18:47:21 -040052 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
53 dif = 0; dix = 1;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040054 }
55
Martin K. Petersen9e066882008-09-19 18:47:21 -040056 if (!dix)
57 return;
58
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040059 memset(&bi, 0, sizeof(bi));
60
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040061 /* Enable DMA of protection information */
Martin K. Petersenaae7df52014-09-26 19:20:05 -040062 if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040063 if (type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040064 bi.profile = &t10_pi_type3_ip;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040065 else
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040066 bi.profile = &t10_pi_type1_ip;
Martin K. Petersenaae7df52014-09-26 19:20:05 -040067
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040068 bi.flags |= BLK_INTEGRITY_IP_CHECKSUM;
Martin K. Petersenaae7df52014-09-26 19:20:05 -040069 } else
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040070 if (type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040071 bi.profile = &t10_pi_type3_crc;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040072 else
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040073 bi.profile = &t10_pi_type1_crc;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040074
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040075 bi.tuple_size = sizeof(struct t10_pi_tuple);
Martin K. Petersencbdc1442008-10-01 01:37:21 -040076 sd_printk(KERN_NOTICE, sdkp,
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040077 "Enabling DIX %s protection\n", bi.profile->name);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040078
Martin K. Petersen3aec2f42014-09-26 19:20:03 -040079 if (dif && type) {
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040080 bi.flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
Martin K. Petersen3aec2f42014-09-26 19:20:03 -040081
Martin K. Petersene5579902015-04-14 17:11:03 -040082 if (!sdkp->ATO)
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040083 goto out;
Martin K. Petersen3aec2f42014-09-26 19:20:03 -040084
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040085 if (type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040086 bi.tag_size = sizeof(u16) + sizeof(u32);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040087 else
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040088 bi.tag_size = sizeof(u16);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040089
Martin K. Petersencbdc1442008-10-01 01:37:21 -040090 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040091 bi.tag_size);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040092 }
Martin K. Petersen0f8087e2015-10-21 13:19:33 -040093
94out:
95 blk_integrity_register(disk, &bi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040096}
97
98/*
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040099 * The virtual start sector is the one that was originally submitted
100 * by the block layer. Due to partitioning, MD/DM cloning, etc. the
101 * actual physical start sector is likely to be different. Remap
102 * protection information to match the physical LBA.
103 *
104 * From a protocol perspective there's a slight difference between
105 * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
106 * reference tag is seeded in the CDB. This gives us the potential to
107 * avoid virt->phys remapping during write. However, at read time we
108 * don't know whether the virt sector is the same as when we wrote it
109 * (we could be reading from real disk as opposed to MD/DM device. So
110 * we always remap Type 2 making it identical to Type 1.
111 *
112 * Type 3 does not have a reference tag so no remapping is required.
113 */
Martin K. Petersenc6115292014-09-26 19:20:08 -0400114void sd_dif_prepare(struct scsi_cmnd *scmd)
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400115{
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400116 const int tuple_sz = sizeof(struct t10_pi_tuple);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400117 struct bio *bio;
118 struct scsi_disk *sdkp;
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400119 struct t10_pi_tuple *pi;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400120 u32 phys, virt;
121
Martin K. Petersenc6115292014-09-26 19:20:08 -0400122 sdkp = scsi_disk(scmd->request->rq_disk);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400123
124 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen8c579ab2012-08-28 14:29:33 -0400125 return;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400126
Martin K. Petersenc6115292014-09-26 19:20:08 -0400127 phys = scsi_prot_ref_tag(scmd);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400128
Martin K. Petersenc6115292014-09-26 19:20:08 -0400129 __rq_for_each_bio(bio, scmd->request) {
Martin K. Petersen18593082014-09-26 19:20:01 -0400130 struct bio_integrity_payload *bip = bio_integrity(bio);
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800131 struct bio_vec iv;
132 struct bvec_iter iter;
133 unsigned int j;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400134
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200135 /* Already remapped? */
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400136 if (bip->bip_flags & BIP_MAPPED_INTEGRITY)
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200137 break;
138
Martin K. Petersen18593082014-09-26 19:20:01 -0400139 virt = bip_get_seed(bip) & 0xffffffff;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400140
Martin K. Petersen18593082014-09-26 19:20:01 -0400141 bip_for_each_vec(iv, bip, iter) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400142 pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400143
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400144 for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400145
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400146 if (be32_to_cpu(pi->ref_tag) == virt)
147 pi->ref_tag = cpu_to_be32(phys);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400148
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400149 virt++;
150 phys++;
151 }
152
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400153 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400154 }
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200155
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400156 bip->bip_flags |= BIP_MAPPED_INTEGRITY;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400157 }
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400158}
159
160/*
161 * Remap physical sector values in the reference tag to the virtual
162 * values expected by the block layer.
163 */
164void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
165{
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400166 const int tuple_sz = sizeof(struct t10_pi_tuple);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400167 struct scsi_disk *sdkp;
168 struct bio *bio;
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400169 struct t10_pi_tuple *pi;
Martin K. Petersenc6115292014-09-26 19:20:08 -0400170 unsigned int j, intervals;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400171 u32 phys, virt;
172
173 sdkp = scsi_disk(scmd->request->rq_disk);
174
175 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
176 return;
177
Martin K. Petersenc6115292014-09-26 19:20:08 -0400178 intervals = good_bytes / scsi_prot_interval(scmd);
179 phys = scsi_prot_ref_tag(scmd);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400180
181 __rq_for_each_bio(bio, scmd->request) {
Martin K. Petersen18593082014-09-26 19:20:01 -0400182 struct bio_integrity_payload *bip = bio_integrity(bio);
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800183 struct bio_vec iv;
184 struct bvec_iter iter;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400185
Martin K. Petersen18593082014-09-26 19:20:01 -0400186 virt = bip_get_seed(bip) & 0xffffffff;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400187
Martin K. Petersen18593082014-09-26 19:20:01 -0400188 bip_for_each_vec(iv, bip, iter) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400189 pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400190
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400191 for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400192
Martin K. Petersenc6115292014-09-26 19:20:08 -0400193 if (intervals == 0) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400194 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400195 return;
196 }
197
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400198 if (be32_to_cpu(pi->ref_tag) == phys)
199 pi->ref_tag = cpu_to_be32(virt);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400200
201 virt++;
202 phys++;
Martin K. Petersenc6115292014-09-26 19:20:08 -0400203 intervals--;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400204 }
205
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400206 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400207 }
208 }
209}
210