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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. Petersen9e066882008-09-19 18:47:21 -040046 int dif, dix;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040047
Martin K. Petersen9e066882008-09-19 18:47:21 -040048 dif = scsi_host_dif_capable(sdp->host, type);
49 dix = scsi_host_dix_capable(sdp->host, type);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040050
Martin K. Petersen9e066882008-09-19 18:47:21 -040051 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
52 dif = 0; dix = 1;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040053 }
54
Martin K. Petersen9e066882008-09-19 18:47:21 -040055 if (!dix)
56 return;
57
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040058 /* Enable DMA of protection information */
Martin K. Petersenaae7df52014-09-26 19:20:05 -040059 if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040060 if (type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen2341c2f2014-09-26 19:20:07 -040061 blk_integrity_register(disk, &t10_pi_type3_ip);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040062 else
Martin K. Petersen2341c2f2014-09-26 19:20:07 -040063 blk_integrity_register(disk, &t10_pi_type1_ip);
Martin K. Petersenaae7df52014-09-26 19:20:05 -040064
65 disk->integrity->flags |= BLK_INTEGRITY_IP_CHECKSUM;
66 } else
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040067 if (type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen2341c2f2014-09-26 19:20:07 -040068 blk_integrity_register(disk, &t10_pi_type3_crc);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040069 else
Martin K. Petersen2341c2f2014-09-26 19:20:07 -040070 blk_integrity_register(disk, &t10_pi_type1_crc);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040071
Martin K. Petersencbdc1442008-10-01 01:37:21 -040072 sd_printk(KERN_NOTICE, sdkp,
Martin K. Petersen9e066882008-09-19 18:47:21 -040073 "Enabling DIX %s protection\n", disk->integrity->name);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040074
75 /* Signal to block layer that we support sector tagging */
Martin K. Petersen3aec2f42014-09-26 19:20:03 -040076 if (dif && type) {
77
78 disk->integrity->flags |= BLK_INTEGRITY_DEVICE_CAPABLE;
79
Martin K. Petersene5579902015-04-14 17:11:03 -040080 if (!sdkp->ATO)
Martin K. Petersen3aec2f42014-09-26 19:20:03 -040081 return;
82
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040083 if (type == SD_DIF_TYPE3_PROTECTION)
84 disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
85 else
86 disk->integrity->tag_size = sizeof(u16);
87
Martin K. Petersencbdc1442008-10-01 01:37:21 -040088 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040089 disk->integrity->tag_size);
90 }
91}
92
93/*
Martin K. Petersenaf55ff62008-07-17 04:28:35 -040094 * The virtual start sector is the one that was originally submitted
95 * by the block layer. Due to partitioning, MD/DM cloning, etc. the
96 * actual physical start sector is likely to be different. Remap
97 * protection information to match the physical LBA.
98 *
99 * From a protocol perspective there's a slight difference between
100 * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
101 * reference tag is seeded in the CDB. This gives us the potential to
102 * avoid virt->phys remapping during write. However, at read time we
103 * don't know whether the virt sector is the same as when we wrote it
104 * (we could be reading from real disk as opposed to MD/DM device. So
105 * we always remap Type 2 making it identical to Type 1.
106 *
107 * Type 3 does not have a reference tag so no remapping is required.
108 */
Martin K. Petersenc6115292014-09-26 19:20:08 -0400109void sd_dif_prepare(struct scsi_cmnd *scmd)
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400110{
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400111 const int tuple_sz = sizeof(struct t10_pi_tuple);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400112 struct bio *bio;
113 struct scsi_disk *sdkp;
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400114 struct t10_pi_tuple *pi;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400115 u32 phys, virt;
116
Martin K. Petersenc6115292014-09-26 19:20:08 -0400117 sdkp = scsi_disk(scmd->request->rq_disk);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400118
119 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
Martin K. Petersen8c579ab2012-08-28 14:29:33 -0400120 return;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400121
Martin K. Petersenc6115292014-09-26 19:20:08 -0400122 phys = scsi_prot_ref_tag(scmd);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400123
Martin K. Petersenc6115292014-09-26 19:20:08 -0400124 __rq_for_each_bio(bio, scmd->request) {
Martin K. Petersen18593082014-09-26 19:20:01 -0400125 struct bio_integrity_payload *bip = bio_integrity(bio);
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800126 struct bio_vec iv;
127 struct bvec_iter iter;
128 unsigned int j;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400129
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200130 /* Already remapped? */
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400131 if (bip->bip_flags & BIP_MAPPED_INTEGRITY)
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200132 break;
133
Martin K. Petersen18593082014-09-26 19:20:01 -0400134 virt = bip_get_seed(bip) & 0xffffffff;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400135
Martin K. Petersen18593082014-09-26 19:20:01 -0400136 bip_for_each_vec(iv, bip, iter) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400137 pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400138
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400139 for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400140
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400141 if (be32_to_cpu(pi->ref_tag) == virt)
142 pi->ref_tag = cpu_to_be32(phys);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400143
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400144 virt++;
145 phys++;
146 }
147
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400148 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400149 }
Martin K. Petersen495d2b32010-10-15 15:49:20 +0200150
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400151 bip->bip_flags |= BIP_MAPPED_INTEGRITY;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400152 }
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400153}
154
155/*
156 * Remap physical sector values in the reference tag to the virtual
157 * values expected by the block layer.
158 */
159void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
160{
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400161 const int tuple_sz = sizeof(struct t10_pi_tuple);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400162 struct scsi_disk *sdkp;
163 struct bio *bio;
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400164 struct t10_pi_tuple *pi;
Martin K. Petersenc6115292014-09-26 19:20:08 -0400165 unsigned int j, intervals;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400166 u32 phys, virt;
167
168 sdkp = scsi_disk(scmd->request->rq_disk);
169
170 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
171 return;
172
Martin K. Petersenc6115292014-09-26 19:20:08 -0400173 intervals = good_bytes / scsi_prot_interval(scmd);
174 phys = scsi_prot_ref_tag(scmd);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400175
176 __rq_for_each_bio(bio, scmd->request) {
Martin K. Petersen18593082014-09-26 19:20:01 -0400177 struct bio_integrity_payload *bip = bio_integrity(bio);
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800178 struct bio_vec iv;
179 struct bvec_iter iter;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400180
Martin K. Petersen18593082014-09-26 19:20:01 -0400181 virt = bip_get_seed(bip) & 0xffffffff;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400182
Martin K. Petersen18593082014-09-26 19:20:01 -0400183 bip_for_each_vec(iv, bip, iter) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400184 pi = kmap_atomic(iv.bv_page) + iv.bv_offset;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400185
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400186 for (j = 0; j < iv.bv_len; j += tuple_sz, pi++) {
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400187
Martin K. Petersenc6115292014-09-26 19:20:08 -0400188 if (intervals == 0) {
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400189 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400190 return;
191 }
192
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400193 if (be32_to_cpu(pi->ref_tag) == phys)
194 pi->ref_tag = cpu_to_be32(virt);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400195
196 virt++;
197 phys++;
Martin K. Petersenc6115292014-09-26 19:20:08 -0400198 intervals--;
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400199 }
200
Martin K. Petersen2341c2f2014-09-26 19:20:07 -0400201 kunmap_atomic(pi);
Martin K. Petersenaf55ff62008-07-17 04:28:35 -0400202 }
203 }
204}
205