x86/xen: resume timer irqs early
[linux/fpc-iii.git] / drivers / scsi / sd_dif.c
blob6174ca4ea27594487d7dc0828d9e21841742b8ed
1 /*
2 * sd_dif.c - SCSI Data Integrity Field
4 * Copyright (C) 2007, 2008 Oracle Corporation
5 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
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.
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.
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.
23 #include <linux/blkdev.h>
24 #include <linux/crc-t10dif.h>
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>
36 #include <net/checksum.h>
38 #include "sd.h"
40 typedef __u16 (csum_fn) (void *, unsigned int);
42 static __u16 sd_dif_crc_fn(void *data, unsigned int len)
44 return cpu_to_be16(crc_t10dif(data, len));
47 static __u16 sd_dif_ip_fn(void *data, unsigned int len)
49 return ip_compute_csum(data, len);
53 * Type 1 and Type 2 protection use the same format: 16 bit guard tag,
54 * 16 bit app tag, 32 bit reference tag.
56 static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
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;
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;
68 buf += bix->sector_size;
69 sector++;
73 static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
75 sd_dif_type1_generate(bix, sd_dif_crc_fn);
78 static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
80 sd_dif_type1_generate(bix, sd_dif_ip_fn);
83 static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
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;
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;
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;
104 csum = fn(buf, bix->sector_size);
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;
114 buf += bix->sector_size;
115 sector++;
118 return 0;
121 static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
123 return sd_dif_type1_verify(bix, sd_dif_crc_fn);
126 static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
128 return sd_dif_type1_verify(bix, sd_dif_ip_fn);
132 * Functions for interleaving and deinterleaving application tags
134 static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors)
136 struct sd_dif_tuple *sdt = prot;
137 u8 *tag = tag_buf;
138 unsigned int i, j;
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);
146 static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors)
148 struct sd_dif_tuple *sdt = prot;
149 u8 *tag = tag_buf;
150 unsigned int i, j;
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;
158 static 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,
168 static 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,
180 * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
181 * tag space.
183 static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
185 void *buf = bix->data_buf;
186 struct sd_dif_tuple *sdt = bix->prot_buf;
187 unsigned int i;
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;
194 buf += bix->sector_size;
198 static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
200 sd_dif_type3_generate(bix, sd_dif_crc_fn);
203 static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
205 sd_dif_type3_generate(bix, sd_dif_ip_fn);
208 static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
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;
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;
221 csum = fn(buf, bix->sector_size);
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;
231 buf += bix->sector_size;
232 sector++;
235 return 0;
238 static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
240 return sd_dif_type3_verify(bix, sd_dif_crc_fn);
243 static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
245 return sd_dif_type3_verify(bix, sd_dif_ip_fn);
248 static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors)
250 struct sd_dif_tuple *sdt = prot;
251 u8 *tag = tag_buf;
252 unsigned int i, j;
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];
261 static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors)
263 struct sd_dif_tuple *sdt = prot;
264 u8 *tag = tag_buf;
265 unsigned int i, j;
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);
278 static 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,
288 static 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,
299 * Configure exchange of protection information between OS and HBA.
301 void sd_dif_config_host(struct scsi_disk *sdkp)
303 struct scsi_device *sdp = sdkp->device;
304 struct gendisk *disk = sdkp->disk;
305 u8 type = sdkp->protection_type;
306 int dif, dix;
308 dif = scsi_host_dif_capable(sdp->host, type);
309 dix = scsi_host_dix_capable(sdp->host, type);
311 if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
312 dif = 0; dix = 1;
315 if (!dix)
316 return;
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);
330 sd_printk(KERN_NOTICE, sdkp,
331 "Enabling DIX %s protection\n", disk->integrity->name);
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);
340 sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
341 disk->integrity->tag_size);
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.
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.
359 * Type 3 does not have a reference tag so no remapping is required.
361 void sd_dif_prepare(struct request *rq, sector_t hw_sector,
362 unsigned int sector_sz)
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 unsigned int i, j;
369 u32 phys, virt;
371 sdkp = rq->bio->bi_bdev->bd_disk->private_data;
373 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
374 return;
376 phys = hw_sector & 0xffffffff;
378 __rq_for_each_bio(bio, rq) {
379 struct bio_vec *iv;
381 /* Already remapped? */
382 if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
383 break;
385 virt = bio->bi_integrity->bip_sector & 0xffffffff;
387 bip_for_each_vec(iv, bio->bi_integrity, i) {
388 sdt = kmap_atomic(iv->bv_page)
389 + iv->bv_offset;
391 for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {
393 if (be32_to_cpu(sdt->ref_tag) == virt)
394 sdt->ref_tag = cpu_to_be32(phys);
396 virt++;
397 phys++;
400 kunmap_atomic(sdt);
403 bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY);
408 * Remap physical sector values in the reference tag to the virtual
409 * values expected by the block layer.
411 void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
413 const int tuple_sz = sizeof(struct sd_dif_tuple);
414 struct scsi_disk *sdkp;
415 struct bio *bio;
416 struct sd_dif_tuple *sdt;
417 unsigned int i, j, sectors, sector_sz;
418 u32 phys, virt;
420 sdkp = scsi_disk(scmd->request->rq_disk);
422 if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
423 return;
425 sector_sz = scmd->device->sector_size;
426 sectors = good_bytes / sector_sz;
428 phys = blk_rq_pos(scmd->request) & 0xffffffff;
429 if (sector_sz == 4096)
430 phys >>= 3;
432 __rq_for_each_bio(bio, scmd->request) {
433 struct bio_vec *iv;
435 virt = bio->bi_integrity->bip_sector & 0xffffffff;
437 bip_for_each_vec(iv, bio->bi_integrity, i) {
438 sdt = kmap_atomic(iv->bv_page)
439 + iv->bv_offset;
441 for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {
443 if (sectors == 0) {
444 kunmap_atomic(sdt);
445 return;
448 if (be32_to_cpu(sdt->ref_tag) == phys)
449 sdt->ref_tag = cpu_to_be32(virt);
451 virt++;
452 phys++;
453 sectors--;
456 kunmap_atomic(sdt);