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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/crc-t10dif.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 <net/checksum.h>
37
38#include "sd.h"
39
40typedef __u16 (csum_fn) (void *, unsigned int);
41
42static __u16 sd_dif_crc_fn(void *data, unsigned int len)
43{
44 return cpu_to_be16(crc_t10dif(data, len));
45}
46
47static __u16 sd_dif_ip_fn(void *data, unsigned int len)
48{
49 return ip_compute_csum(data, len);
50}
51
52/*
53 * Type 1 and Type 2 protection use the same format: 16 bit guard tag,
54 * 16 bit app tag, 32 bit reference tag.
55 */
56static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
57{
58 void *buf = bix->data_buf;
59 struct sd_dif_tuple *sdt = bix->prot_buf;
60 sector_t sector = bix->sector;
61 unsigned int i;
62
63 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
64 sdt->guard_tag = fn(buf, bix->sector_size);
65 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
66 sdt->app_tag = 0;
67
68 buf += bix->sector_size;
69 sector++;
70 }
71}
72
73static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
74{
75 sd_dif_type1_generate(bix, sd_dif_crc_fn);
76}
77
78static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
79{
80 sd_dif_type1_generate(bix, sd_dif_ip_fn);
81}
82
83static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
84{
85 void *buf = bix->data_buf;
86 struct sd_dif_tuple *sdt = bix->prot_buf;
87 sector_t sector = bix->sector;
88 unsigned int i;
89 __u16 csum;
90
91 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
92 /* Unwritten sectors */
93 if (sdt->app_tag == 0xffff)
94 return 0;
95
96 /* Bad ref tag received from disk */
97 if (sdt->ref_tag == 0xffffffff) {
98 printk(KERN_ERR
99 "%s: bad phys ref tag on sector %lu\n",
100 bix->disk_name, (unsigned long)sector);
101 return -EIO;
102 }
103
104 if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
105 printk(KERN_ERR
106 "%s: ref tag error on sector %lu (rcvd %u)\n",
107 bix->disk_name, (unsigned long)sector,
108 be32_to_cpu(sdt->ref_tag));
109 return -EIO;
110 }
111
112 csum = fn(buf, bix->sector_size);
113
114 if (sdt->guard_tag != csum) {
115 printk(KERN_ERR "%s: guard tag error on sector %lu " \
116 "(rcvd %04x, data %04x)\n", bix->disk_name,
117 (unsigned long)sector,
118 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
119 return -EIO;
120 }
121
122 buf += bix->sector_size;
123 sector++;
124 }
125
126 return 0;
127}
128
129static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
130{
131 return sd_dif_type1_verify(bix, sd_dif_crc_fn);
132}
133
134static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
135{
136 return sd_dif_type1_verify(bix, sd_dif_ip_fn);
137}
138
139/*
140 * Functions for interleaving and deinterleaving application tags
141 */
142static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors)
143{
144 struct sd_dif_tuple *sdt = prot;
145 u8 *tag = tag_buf;
146 unsigned int i, j;
147
148 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
149 sdt->app_tag = tag[j] << 8 | tag[j+1];
150 BUG_ON(sdt->app_tag == 0xffff);
151 }
152}
153
154static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors)
155{
156 struct sd_dif_tuple *sdt = prot;
157 u8 *tag = tag_buf;
158 unsigned int i, j;
159
160 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
161 tag[j] = (sdt->app_tag & 0xff00) >> 8;
162 tag[j+1] = sdt->app_tag & 0xff;
163 }
164}
165
166static struct blk_integrity dif_type1_integrity_crc = {
167 .name = "T10-DIF-TYPE1-CRC",
168 .generate_fn = sd_dif_type1_generate_crc,
169 .verify_fn = sd_dif_type1_verify_crc,
170 .get_tag_fn = sd_dif_type1_get_tag,
171 .set_tag_fn = sd_dif_type1_set_tag,
172 .tuple_size = sizeof(struct sd_dif_tuple),
173 .tag_size = 0,
174};
175
176static struct blk_integrity dif_type1_integrity_ip = {
177 .name = "T10-DIF-TYPE1-IP",
178 .generate_fn = sd_dif_type1_generate_ip,
179 .verify_fn = sd_dif_type1_verify_ip,
180 .get_tag_fn = sd_dif_type1_get_tag,
181 .set_tag_fn = sd_dif_type1_set_tag,
182 .tuple_size = sizeof(struct sd_dif_tuple),
183 .tag_size = 0,
184};
185
186
187/*
188 * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
189 * tag space.
190 */
191static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
192{
193 void *buf = bix->data_buf;
194 struct sd_dif_tuple *sdt = bix->prot_buf;
195 unsigned int i;
196
197 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
198 sdt->guard_tag = fn(buf, bix->sector_size);
199 sdt->ref_tag = 0;
200 sdt->app_tag = 0;
201
202 buf += bix->sector_size;
203 }
204}
205
206static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
207{
208 sd_dif_type3_generate(bix, sd_dif_crc_fn);
209}
210
211static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
212{
213 sd_dif_type3_generate(bix, sd_dif_ip_fn);
214}
215
216static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
217{
218 void *buf = bix->data_buf;
219 struct sd_dif_tuple *sdt = bix->prot_buf;
220 sector_t sector = bix->sector;
221 unsigned int i;
222 __u16 csum;
223
224 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
225 /* Unwritten sectors */
226 if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
227 return 0;
228
229 csum = fn(buf, bix->sector_size);
230
231 if (sdt->guard_tag != csum) {
232 printk(KERN_ERR "%s: guard tag error on sector %lu " \
233 "(rcvd %04x, data %04x)\n", bix->disk_name,
234 (unsigned long)sector,
235 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
236 return -EIO;
237 }
238
239 buf += bix->sector_size;
240 sector++;
241 }
242
243 return 0;
244}
245
246static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
247{
248 return sd_dif_type3_verify(bix, sd_dif_crc_fn);
249}
250
251static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
252{
253 return sd_dif_type3_verify(bix, sd_dif_ip_fn);
254}
255
256static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors)
257{
258 struct sd_dif_tuple *sdt = prot;
259 u8 *tag = tag_buf;
260 unsigned int i, j;
261
262 for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) {
263 sdt->app_tag = tag[j] << 8 | tag[j+1];
264 sdt->ref_tag = tag[j+2] << 24 | tag[j+3] << 16 |
265 tag[j+4] << 8 | tag[j+5];
266 }
267}
268
269static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors)
270{
271 struct sd_dif_tuple *sdt = prot;
272 u8 *tag = tag_buf;
273 unsigned int i, j;
274
275 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
276 tag[j] = (sdt->app_tag & 0xff00) >> 8;
277 tag[j+1] = sdt->app_tag & 0xff;
278 tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24;
279 tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16;
280 tag[j+4] = (sdt->ref_tag & 0xff00) >> 8;
281 tag[j+5] = sdt->ref_tag & 0xff;
282 BUG_ON(sdt->app_tag == 0xffff || sdt->ref_tag == 0xffffffff);
283 }
284}
285
286static struct blk_integrity dif_type3_integrity_crc = {
287 .name = "T10-DIF-TYPE3-CRC",
288 .generate_fn = sd_dif_type3_generate_crc,
289 .verify_fn = sd_dif_type3_verify_crc,
290 .get_tag_fn = sd_dif_type3_get_tag,
291 .set_tag_fn = sd_dif_type3_set_tag,
292 .tuple_size = sizeof(struct sd_dif_tuple),
293 .tag_size = 0,
294};
295
296static struct blk_integrity dif_type3_integrity_ip = {
297 .name = "T10-DIF-TYPE3-IP",
298 .generate_fn = sd_dif_type3_generate_ip,
299 .verify_fn = sd_dif_type3_verify_ip,
300 .get_tag_fn = sd_dif_type3_get_tag,
301 .set_tag_fn = sd_dif_type3_set_tag,
302 .tuple_size = sizeof(struct sd_dif_tuple),
303 .tag_size = 0,
304};
305
306/*
307 * Configure exchange of protection information between OS and HBA.
308 */
309void sd_dif_config_host(struct scsi_disk *sdkp)
310{
311 struct scsi_device *sdp = sdkp->device;
312 struct gendisk *disk = sdkp->disk;
313 u8 type = sdkp->protection_type;
314 int dif, dix;
315
316 dif = scsi_host_dif_capable(sdp->host, type);
317 dix = scsi_host_dix_capable(sdp->host, type);
318
319 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
320 dif = 0; dix = 1;
321 }
322
323 if (!dix)
324 return;
325
326 /* Enable DMA of protection information */
327 if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
328 if (type == SD_DIF_TYPE3_PROTECTION)
329 blk_integrity_register(disk, &dif_type3_integrity_ip);
330 else
331 blk_integrity_register(disk, &dif_type1_integrity_ip);
332 else
333 if (type == SD_DIF_TYPE3_PROTECTION)
334 blk_integrity_register(disk, &dif_type3_integrity_crc);
335 else
336 blk_integrity_register(disk, &dif_type1_integrity_crc);
337
338 sd_printk(KERN_NOTICE, sdkp,
339 "Enabling DIX %s protection\n", disk->integrity->name);
340
341 /* Signal to block layer that we support sector tagging */
342 if (dif && type && sdkp->ATO) {
343 if (type == SD_DIF_TYPE3_PROTECTION)
344 disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
345 else
346 disk->integrity->tag_size = sizeof(u16);
347
348 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
349 disk->integrity->tag_size);
350 }
351}
352
353/*
354 * The virtual start sector is the one that was originally submitted
355 * by the block layer. Due to partitioning, MD/DM cloning, etc. the
356 * actual physical start sector is likely to be different. Remap
357 * protection information to match the physical LBA.
358 *
359 * From a protocol perspective there's a slight difference between
360 * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
361 * reference tag is seeded in the CDB. This gives us the potential to
362 * avoid virt->phys remapping during write. However, at read time we
363 * don't know whether the virt sector is the same as when we wrote it
364 * (we could be reading from real disk as opposed to MD/DM device. So
365 * we always remap Type 2 making it identical to Type 1.
366 *
367 * Type 3 does not have a reference tag so no remapping is required.
368 */
369int sd_dif_prepare(struct request *rq, sector_t hw_sector, unsigned int sector_sz)
370{
371 const int tuple_sz = sizeof(struct sd_dif_tuple);
372 struct bio *bio;
373 struct scsi_disk *sdkp;
374 struct sd_dif_tuple *sdt;
375 unsigned int i, j;
376 u32 phys, virt;
377
378 sdkp = rq->bio->bi_bdev->bd_disk->private_data;
379
380 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
381 return 0;
382
383 phys = hw_sector & 0xffffffff;
384
385 __rq_for_each_bio(bio, rq) {
386 struct bio_vec *iv;
387
388 /* Already remapped? */
389 if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
390 break;
391
392 virt = bio->bi_integrity->bip_sector & 0xffffffff;
393
394 bip_for_each_vec(iv, bio->bi_integrity, i) {
395 sdt = kmap_atomic(iv->bv_page, KM_USER0)
396 + iv->bv_offset;
397
398 for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {
399
400 if (be32_to_cpu(sdt->ref_tag) != virt)
401 goto error;
402
403 sdt->ref_tag = cpu_to_be32(phys);
404 virt++;
405 phys++;
406 }
407
408 kunmap_atomic(sdt, KM_USER0);
409 }
410
411 bio->bi_flags |= BIO_MAPPED_INTEGRITY;
412 }
413
414 return 0;
415
416error:
417 kunmap_atomic(sdt, KM_USER0);
418 sd_printk(KERN_ERR, sdkp, "%s: virt %u, phys %u, ref %u, app %4x\n",
419 __func__, virt, phys, be32_to_cpu(sdt->ref_tag),
420 be16_to_cpu(sdt->app_tag));
421
422 return -EILSEQ;
423}
424
425/*
426 * Remap physical sector values in the reference tag to the virtual
427 * values expected by the block layer.
428 */
429void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
430{
431 const int tuple_sz = sizeof(struct sd_dif_tuple);
432 struct scsi_disk *sdkp;
433 struct bio *bio;
434 struct sd_dif_tuple *sdt;
435 unsigned int i, j, sectors, sector_sz;
436 u32 phys, virt;
437
438 sdkp = scsi_disk(scmd->request->rq_disk);
439
440 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
441 return;
442
443 sector_sz = scmd->device->sector_size;
444 sectors = good_bytes / sector_sz;
445
446 phys = blk_rq_pos(scmd->request) & 0xffffffff;
447 if (sector_sz == 4096)
448 phys >>= 3;
449
450 __rq_for_each_bio(bio, scmd->request) {
451 struct bio_vec *iv;
452
453 virt = bio->bi_integrity->bip_sector & 0xffffffff;
454
455 bip_for_each_vec(iv, bio->bi_integrity, i) {
456 sdt = kmap_atomic(iv->bv_page, KM_USER0)
457 + iv->bv_offset;
458
459 for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {
460
461 if (sectors == 0) {
462 kunmap_atomic(sdt, KM_USER0);
463 return;
464 }
465
466 if (be32_to_cpu(sdt->ref_tag) != phys &&
467 sdt->app_tag != 0xffff)
468 sdt->ref_tag = 0xffffffff; /* Bad ref */
469 else
470 sdt->ref_tag = cpu_to_be32(virt);
471
472 virt++;
473 phys++;
474 sectors--;
475 }
476
477 kunmap_atomic(sdt, KM_USER0);
478 }
479 }
480}
481
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/crc-t10dif.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 <net/checksum.h>
37
38#include "sd.h"
39
40typedef __u16 (csum_fn) (void *, unsigned int);
41
42static __u16 sd_dif_crc_fn(void *data, unsigned int len)
43{
44 return cpu_to_be16(crc_t10dif(data, len));
45}
46
47static __u16 sd_dif_ip_fn(void *data, unsigned int len)
48{
49 return ip_compute_csum(data, len);
50}
51
52/*
53 * Type 1 and Type 2 protection use the same format: 16 bit guard tag,
54 * 16 bit app tag, 32 bit reference tag.
55 */
56static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
57{
58 void *buf = bix->data_buf;
59 struct sd_dif_tuple *sdt = bix->prot_buf;
60 sector_t sector = bix->sector;
61 unsigned int i;
62
63 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
64 sdt->guard_tag = fn(buf, bix->sector_size);
65 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
66 sdt->app_tag = 0;
67
68 buf += bix->sector_size;
69 sector++;
70 }
71}
72
73static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
74{
75 sd_dif_type1_generate(bix, sd_dif_crc_fn);
76}
77
78static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
79{
80 sd_dif_type1_generate(bix, sd_dif_ip_fn);
81}
82
83static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
84{
85 void *buf = bix->data_buf;
86 struct sd_dif_tuple *sdt = bix->prot_buf;
87 sector_t sector = bix->sector;
88 unsigned int i;
89 __u16 csum;
90
91 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
92 /* Unwritten sectors */
93 if (sdt->app_tag == 0xffff)
94 return 0;
95
96 if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
97 printk(KERN_ERR
98 "%s: ref tag error on sector %lu (rcvd %u)\n",
99 bix->disk_name, (unsigned long)sector,
100 be32_to_cpu(sdt->ref_tag));
101 return -EIO;
102 }
103
104 csum = fn(buf, bix->sector_size);
105
106 if (sdt->guard_tag != csum) {
107 printk(KERN_ERR "%s: guard tag error on sector %lu " \
108 "(rcvd %04x, data %04x)\n", bix->disk_name,
109 (unsigned long)sector,
110 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
111 return -EIO;
112 }
113
114 buf += bix->sector_size;
115 sector++;
116 }
117
118 return 0;
119}
120
121static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
122{
123 return sd_dif_type1_verify(bix, sd_dif_crc_fn);
124}
125
126static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
127{
128 return sd_dif_type1_verify(bix, sd_dif_ip_fn);
129}
130
131/*
132 * Functions for interleaving and deinterleaving application tags
133 */
134static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors)
135{
136 struct sd_dif_tuple *sdt = prot;
137 u8 *tag = tag_buf;
138 unsigned int i, j;
139
140 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
141 sdt->app_tag = tag[j] << 8 | tag[j+1];
142 BUG_ON(sdt->app_tag == 0xffff);
143 }
144}
145
146static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors)
147{
148 struct sd_dif_tuple *sdt = prot;
149 u8 *tag = tag_buf;
150 unsigned int i, j;
151
152 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
153 tag[j] = (sdt->app_tag & 0xff00) >> 8;
154 tag[j+1] = sdt->app_tag & 0xff;
155 }
156}
157
158static struct blk_integrity dif_type1_integrity_crc = {
159 .name = "T10-DIF-TYPE1-CRC",
160 .generate_fn = sd_dif_type1_generate_crc,
161 .verify_fn = sd_dif_type1_verify_crc,
162 .get_tag_fn = sd_dif_type1_get_tag,
163 .set_tag_fn = sd_dif_type1_set_tag,
164 .tuple_size = sizeof(struct sd_dif_tuple),
165 .tag_size = 0,
166};
167
168static struct blk_integrity dif_type1_integrity_ip = {
169 .name = "T10-DIF-TYPE1-IP",
170 .generate_fn = sd_dif_type1_generate_ip,
171 .verify_fn = sd_dif_type1_verify_ip,
172 .get_tag_fn = sd_dif_type1_get_tag,
173 .set_tag_fn = sd_dif_type1_set_tag,
174 .tuple_size = sizeof(struct sd_dif_tuple),
175 .tag_size = 0,
176};
177
178
179/*
180 * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
181 * tag space.
182 */
183static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
184{
185 void *buf = bix->data_buf;
186 struct sd_dif_tuple *sdt = bix->prot_buf;
187 unsigned int i;
188
189 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
190 sdt->guard_tag = fn(buf, bix->sector_size);
191 sdt->ref_tag = 0;
192 sdt->app_tag = 0;
193
194 buf += bix->sector_size;
195 }
196}
197
198static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
199{
200 sd_dif_type3_generate(bix, sd_dif_crc_fn);
201}
202
203static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
204{
205 sd_dif_type3_generate(bix, sd_dif_ip_fn);
206}
207
208static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
209{
210 void *buf = bix->data_buf;
211 struct sd_dif_tuple *sdt = bix->prot_buf;
212 sector_t sector = bix->sector;
213 unsigned int i;
214 __u16 csum;
215
216 for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
217 /* Unwritten sectors */
218 if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
219 return 0;
220
221 csum = fn(buf, bix->sector_size);
222
223 if (sdt->guard_tag != csum) {
224 printk(KERN_ERR "%s: guard tag error on sector %lu " \
225 "(rcvd %04x, data %04x)\n", bix->disk_name,
226 (unsigned long)sector,
227 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
228 return -EIO;
229 }
230
231 buf += bix->sector_size;
232 sector++;
233 }
234
235 return 0;
236}
237
238static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
239{
240 return sd_dif_type3_verify(bix, sd_dif_crc_fn);
241}
242
243static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
244{
245 return sd_dif_type3_verify(bix, sd_dif_ip_fn);
246}
247
248static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors)
249{
250 struct sd_dif_tuple *sdt = prot;
251 u8 *tag = tag_buf;
252 unsigned int i, j;
253
254 for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) {
255 sdt->app_tag = tag[j] << 8 | tag[j+1];
256 sdt->ref_tag = tag[j+2] << 24 | tag[j+3] << 16 |
257 tag[j+4] << 8 | tag[j+5];
258 }
259}
260
261static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors)
262{
263 struct sd_dif_tuple *sdt = prot;
264 u8 *tag = tag_buf;
265 unsigned int i, j;
266
267 for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
268 tag[j] = (sdt->app_tag & 0xff00) >> 8;
269 tag[j+1] = sdt->app_tag & 0xff;
270 tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24;
271 tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16;
272 tag[j+4] = (sdt->ref_tag & 0xff00) >> 8;
273 tag[j+5] = sdt->ref_tag & 0xff;
274 BUG_ON(sdt->app_tag == 0xffff || sdt->ref_tag == 0xffffffff);
275 }
276}
277
278static struct blk_integrity dif_type3_integrity_crc = {
279 .name = "T10-DIF-TYPE3-CRC",
280 .generate_fn = sd_dif_type3_generate_crc,
281 .verify_fn = sd_dif_type3_verify_crc,
282 .get_tag_fn = sd_dif_type3_get_tag,
283 .set_tag_fn = sd_dif_type3_set_tag,
284 .tuple_size = sizeof(struct sd_dif_tuple),
285 .tag_size = 0,
286};
287
288static struct blk_integrity dif_type3_integrity_ip = {
289 .name = "T10-DIF-TYPE3-IP",
290 .generate_fn = sd_dif_type3_generate_ip,
291 .verify_fn = sd_dif_type3_verify_ip,
292 .get_tag_fn = sd_dif_type3_get_tag,
293 .set_tag_fn = sd_dif_type3_set_tag,
294 .tuple_size = sizeof(struct sd_dif_tuple),
295 .tag_size = 0,
296};
297
298/*
299 * Configure exchange of protection information between OS and HBA.
300 */
301void sd_dif_config_host(struct scsi_disk *sdkp)
302{
303 struct scsi_device *sdp = sdkp->device;
304 struct gendisk *disk = sdkp->disk;
305 u8 type = sdkp->protection_type;
306 int dif, dix;
307
308 dif = scsi_host_dif_capable(sdp->host, type);
309 dix = scsi_host_dix_capable(sdp->host, type);
310
311 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
312 dif = 0; dix = 1;
313 }
314
315 if (!dix)
316 return;
317
318 /* Enable DMA of protection information */
319 if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
320 if (type == SD_DIF_TYPE3_PROTECTION)
321 blk_integrity_register(disk, &dif_type3_integrity_ip);
322 else
323 blk_integrity_register(disk, &dif_type1_integrity_ip);
324 else
325 if (type == SD_DIF_TYPE3_PROTECTION)
326 blk_integrity_register(disk, &dif_type3_integrity_crc);
327 else
328 blk_integrity_register(disk, &dif_type1_integrity_crc);
329
330 sd_printk(KERN_NOTICE, sdkp,
331 "Enabling DIX %s protection\n", disk->integrity->name);
332
333 /* Signal to block layer that we support sector tagging */
334 if (dif && type && sdkp->ATO) {
335 if (type == SD_DIF_TYPE3_PROTECTION)
336 disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
337 else
338 disk->integrity->tag_size = sizeof(u16);
339
340 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
341 disk->integrity->tag_size);
342 }
343}
344
345/*
346 * The virtual start sector is the one that was originally submitted
347 * by the block layer. Due to partitioning, MD/DM cloning, etc. the
348 * actual physical start sector is likely to be different. Remap
349 * protection information to match the physical LBA.
350 *
351 * From a protocol perspective there's a slight difference between
352 * Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
353 * reference tag is seeded in the CDB. This gives us the potential to
354 * avoid virt->phys remapping during write. However, at read time we
355 * don't know whether the virt sector is the same as when we wrote it
356 * (we could be reading from real disk as opposed to MD/DM device. So
357 * we always remap Type 2 making it identical to Type 1.
358 *
359 * Type 3 does not have a reference tag so no remapping is required.
360 */
361void sd_dif_prepare(struct request *rq, sector_t hw_sector,
362 unsigned int sector_sz)
363{
364 const int tuple_sz = sizeof(struct sd_dif_tuple);
365 struct bio *bio;
366 struct scsi_disk *sdkp;
367 struct sd_dif_tuple *sdt;
368 u32 phys, virt;
369
370 sdkp = rq->bio->bi_bdev->bd_disk->private_data;
371
372 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
373 return;
374
375 phys = hw_sector & 0xffffffff;
376
377 __rq_for_each_bio(bio, rq) {
378 struct bio_vec iv;
379 struct bvec_iter iter;
380 unsigned int j;
381
382 /* Already remapped? */
383 if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
384 break;
385
386 virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
387
388 bip_for_each_vec(iv, bio->bi_integrity, iter) {
389 sdt = kmap_atomic(iv.bv_page)
390 + iv.bv_offset;
391
392 for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
393
394 if (be32_to_cpu(sdt->ref_tag) == virt)
395 sdt->ref_tag = cpu_to_be32(phys);
396
397 virt++;
398 phys++;
399 }
400
401 kunmap_atomic(sdt);
402 }
403
404 bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY);
405 }
406}
407
408/*
409 * Remap physical sector values in the reference tag to the virtual
410 * values expected by the block layer.
411 */
412void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
413{
414 const int tuple_sz = sizeof(struct sd_dif_tuple);
415 struct scsi_disk *sdkp;
416 struct bio *bio;
417 struct sd_dif_tuple *sdt;
418 unsigned int j, sectors, sector_sz;
419 u32 phys, virt;
420
421 sdkp = scsi_disk(scmd->request->rq_disk);
422
423 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
424 return;
425
426 sector_sz = scmd->device->sector_size;
427 sectors = good_bytes / sector_sz;
428
429 phys = blk_rq_pos(scmd->request) & 0xffffffff;
430 if (sector_sz == 4096)
431 phys >>= 3;
432
433 __rq_for_each_bio(bio, scmd->request) {
434 struct bio_vec iv;
435 struct bvec_iter iter;
436
437 virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
438
439 bip_for_each_vec(iv, bio->bi_integrity, iter) {
440 sdt = kmap_atomic(iv.bv_page)
441 + iv.bv_offset;
442
443 for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
444
445 if (sectors == 0) {
446 kunmap_atomic(sdt);
447 return;
448 }
449
450 if (be32_to_cpu(sdt->ref_tag) == phys)
451 sdt->ref_tag = cpu_to_be32(virt);
452
453 virt++;
454 phys++;
455 sectors--;
456 }
457
458 kunmap_atomic(sdt);
459 }
460 }
461}
462