linux/drivers/scsi/sd_dif.c

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/*
* sd_dif.c - SCSI Data Integrity Field
*
* Copyright (C) 2007, 2008 Oracle Corporation
* Written by: Martin K. Petersen <martin.petersen@oracle.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
* USA.
*
*/
#include <linux/blkdev.h>
#include <linux/crc-t10dif.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h>
#include <net/checksum.h>
#include "sd.h"
typedef __u16 (csum_fn) (void *, unsigned int);
static __u16 sd_dif_crc_fn(void *data, unsigned int len)
{
return cpu_to_be16(crc_t10dif(data, len));
}
static __u16 sd_dif_ip_fn(void *data, unsigned int len)
{
return ip_compute_csum(data, len);
}
/*
* Type 1 and Type 2 protection use the same format: 16 bit guard tag,
* 16 bit app tag, 32 bit reference tag.
*/
static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
{
void *buf = bix->data_buf;
struct sd_dif_tuple *sdt = bix->prot_buf;
sector_t sector = bix->sector;
unsigned int i;
for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
sdt->guard_tag = fn(buf, bix->sector_size);
sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
sdt->app_tag = 0;
buf += bix->sector_size;
sector++;
}
}
static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
{
sd_dif_type1_generate(bix, sd_dif_crc_fn);
}
static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
{
sd_dif_type1_generate(bix, sd_dif_ip_fn);
}
static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
{
void *buf = bix->data_buf;
struct sd_dif_tuple *sdt = bix->prot_buf;
sector_t sector = bix->sector;
unsigned int i;
__u16 csum;
for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
/* Unwritten sectors */
if (sdt->app_tag == 0xffff)
return 0;
if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
printk(KERN_ERR
"%s: ref tag error on sector %lu (rcvd %u)\n",
bix->disk_name, (unsigned long)sector,
be32_to_cpu(sdt->ref_tag));
return -EIO;
}
csum = fn(buf, bix->sector_size);
if (sdt->guard_tag != csum) {
printk(KERN_ERR "%s: guard tag error on sector %lu " \
"(rcvd %04x, data %04x)\n", bix->disk_name,
(unsigned long)sector,
be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
return -EIO;
}
buf += bix->sector_size;
sector++;
}
return 0;
}
static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
{
return sd_dif_type1_verify(bix, sd_dif_crc_fn);
}
static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
{
return sd_dif_type1_verify(bix, sd_dif_ip_fn);
}
/*
* Functions for interleaving and deinterleaving application tags
*/
static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors)
{
struct sd_dif_tuple *sdt = prot;
u8 *tag = tag_buf;
unsigned int i, j;
for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
sdt->app_tag = tag[j] << 8 | tag[j+1];
BUG_ON(sdt->app_tag == 0xffff);
}
}
static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors)
{
struct sd_dif_tuple *sdt = prot;
u8 *tag = tag_buf;
unsigned int i, j;
for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
tag[j] = (sdt->app_tag & 0xff00) >> 8;
tag[j+1] = sdt->app_tag & 0xff;
}
}
static struct blk_integrity dif_type1_integrity_crc = {
.name = "T10-DIF-TYPE1-CRC",
.generate_fn = sd_dif_type1_generate_crc,
.verify_fn = sd_dif_type1_verify_crc,
.get_tag_fn = sd_dif_type1_get_tag,
.set_tag_fn = sd_dif_type1_set_tag,
.tuple_size = sizeof(struct sd_dif_tuple),
.tag_size = 0,
};
static struct blk_integrity dif_type1_integrity_ip = {
.name = "T10-DIF-TYPE1-IP",
.generate_fn = sd_dif_type1_generate_ip,
.verify_fn = sd_dif_type1_verify_ip,
.get_tag_fn = sd_dif_type1_get_tag,
.set_tag_fn = sd_dif_type1_set_tag,
.tuple_size = sizeof(struct sd_dif_tuple),
.tag_size = 0,
};
/*
* Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
* tag space.
*/
static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
{
void *buf = bix->data_buf;
struct sd_dif_tuple *sdt = bix->prot_buf;
unsigned int i;
for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
sdt->guard_tag = fn(buf, bix->sector_size);
sdt->ref_tag = 0;
sdt->app_tag = 0;
buf += bix->sector_size;
}
}
static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
{
sd_dif_type3_generate(bix, sd_dif_crc_fn);
}
static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
{
sd_dif_type3_generate(bix, sd_dif_ip_fn);
}
static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
{
void *buf = bix->data_buf;
struct sd_dif_tuple *sdt = bix->prot_buf;
sector_t sector = bix->sector;
unsigned int i;
__u16 csum;
for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
/* Unwritten sectors */
if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
return 0;
csum = fn(buf, bix->sector_size);
if (sdt->guard_tag != csum) {
printk(KERN_ERR "%s: guard tag error on sector %lu " \
"(rcvd %04x, data %04x)\n", bix->disk_name,
(unsigned long)sector,
be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
return -EIO;
}
buf += bix->sector_size;
sector++;
}
return 0;
}
static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
{
return sd_dif_type3_verify(bix, sd_dif_crc_fn);
}
static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
{
return sd_dif_type3_verify(bix, sd_dif_ip_fn);
}
static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors)
{
struct sd_dif_tuple *sdt = prot;
u8 *tag = tag_buf;
unsigned int i, j;
for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) {
sdt->app_tag = tag[j] << 8 | tag[j+1];
sdt->ref_tag = tag[j+2] << 24 | tag[j+3] << 16 |
tag[j+4] << 8 | tag[j+5];
}
}
static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors)
{
struct sd_dif_tuple *sdt = prot;
u8 *tag = tag_buf;
unsigned int i, j;
for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
tag[j] = (sdt->app_tag & 0xff00) >> 8;
tag[j+1] = sdt->app_tag & 0xff;
tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24;
tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16;
tag[j+4] = (sdt->ref_tag & 0xff00) >> 8;
tag[j+5] = sdt->ref_tag & 0xff;
BUG_ON(sdt->app_tag == 0xffff || sdt->ref_tag == 0xffffffff);
}
}
static struct blk_integrity dif_type3_integrity_crc = {
.name = "T10-DIF-TYPE3-CRC",
.generate_fn = sd_dif_type3_generate_crc,
.verify_fn = sd_dif_type3_verify_crc,
.get_tag_fn = sd_dif_type3_get_tag,
.set_tag_fn = sd_dif_type3_set_tag,
.tuple_size = sizeof(struct sd_dif_tuple),
.tag_size = 0,
};
static struct blk_integrity dif_type3_integrity_ip = {
.name = "T10-DIF-TYPE3-IP",
.generate_fn = sd_dif_type3_generate_ip,
.verify_fn = sd_dif_type3_verify_ip,
.get_tag_fn = sd_dif_type3_get_tag,
.set_tag_fn = sd_dif_type3_set_tag,
.tuple_size = sizeof(struct sd_dif_tuple),
.tag_size = 0,
};
/*
* Configure exchange of protection information between OS and HBA.
*/
void sd_dif_config_host(struct scsi_disk *sdkp)
{
struct scsi_device *sdp = sdkp->device;
struct gendisk *disk = sdkp->disk;
u8 type = sdkp->protection_type;
int dif, dix;
dif = scsi_host_dif_capable(sdp->host, type);
dix = scsi_host_dix_capable(sdp->host, type);
if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
dif = 0; dix = 1;
}
if (!dix)
return;
/* Enable DMA of protection information */
if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
if (type == SD_DIF_TYPE3_PROTECTION)
blk_integrity_register(disk, &dif_type3_integrity_ip);
else
blk_integrity_register(disk, &dif_type1_integrity_ip);
else
if (type == SD_DIF_TYPE3_PROTECTION)
blk_integrity_register(disk, &dif_type3_integrity_crc);
else
blk_integrity_register(disk, &dif_type1_integrity_crc);
sd_printk(KERN_NOTICE, sdkp,
"Enabling DIX %s protection\n", disk->integrity->name);
/* Signal to block layer that we support sector tagging */
if (dif && type && sdkp->ATO) {
if (type == SD_DIF_TYPE3_PROTECTION)
disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
else
disk->integrity->tag_size = sizeof(u16);
sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
disk->integrity->tag_size);
}
}
/*
* The virtual start sector is the one that was originally submitted
* by the block layer. Due to partitioning, MD/DM cloning, etc. the
* actual physical start sector is likely to be different. Remap
* protection information to match the physical LBA.
*
* From a protocol perspective there's a slight difference between
* Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
* reference tag is seeded in the CDB. This gives us the potential to
* avoid virt->phys remapping during write. However, at read time we
* don't know whether the virt sector is the same as when we wrote it
* (we could be reading from real disk as opposed to MD/DM device. So
* we always remap Type 2 making it identical to Type 1.
*
* Type 3 does not have a reference tag so no remapping is required.
*/
void sd_dif_prepare(struct request *rq, sector_t hw_sector,
unsigned int sector_sz)
{
const int tuple_sz = sizeof(struct sd_dif_tuple);
struct bio *bio;
struct scsi_disk *sdkp;
struct sd_dif_tuple *sdt;
u32 phys, virt;
sdkp = rq->bio->bi_bdev->bd_disk->private_data;
if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
return;
phys = hw_sector & 0xffffffff;
__rq_for_each_bio(bio, rq) {
struct bio_vec iv;
struct bvec_iter iter;
unsigned int j;
/* Already remapped? */
if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
break;
virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
bip_for_each_vec(iv, bio->bi_integrity, iter) {
sdt = kmap_atomic(iv.bv_page)
+ iv.bv_offset;
for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
if (be32_to_cpu(sdt->ref_tag) == virt)
sdt->ref_tag = cpu_to_be32(phys);
virt++;
phys++;
}
kunmap_atomic(sdt);
}
bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY);
}
}
/*
* Remap physical sector values in the reference tag to the virtual
* values expected by the block layer.
*/
void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
{
const int tuple_sz = sizeof(struct sd_dif_tuple);
struct scsi_disk *sdkp;
struct bio *bio;
struct sd_dif_tuple *sdt;
unsigned int j, sectors, sector_sz;
u32 phys, virt;
sdkp = scsi_disk(scmd->request->rq_disk);
if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
return;
sector_sz = scmd->device->sector_size;
sectors = good_bytes / sector_sz;
block: convert to pos and nr_sectors accessors With recent cleanups, there is no place where low level driver directly manipulates request fields. This means that the 'hard' request fields always equal the !hard fields. Convert all rq->sectors, nr_sectors and current_nr_sectors references to accessors. While at it, drop superflous blk_rq_pos() < 0 test in swim.c. [ Impact: use pos and nr_sectors accessors ] Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Tested-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Adrian McMenamin <adrian@mcmen.demon.co.uk> Acked-by: Adrian McMenamin <adrian@mcmen.demon.co.uk> Acked-by: Mike Miller <mike.miller@hp.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Borislav Petkov <petkovbb@googlemail.com> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Eric Moore <Eric.Moore@lsi.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Pete Zaitcev <zaitcev@redhat.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Paul Clements <paul.clements@steeleye.com> Cc: Tim Waugh <tim@cyberelk.net> Cc: Jeff Garzik <jgarzik@pobox.com> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Alex Dubov <oakad@yahoo.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Dario Ballabio <ballabio_dario@emc.com> Cc: David S. Miller <davem@davemloft.net> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: unsik Kim <donari75@gmail.com> Cc: Laurent Vivier <Laurent@lvivier.info> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-07 21:24:39 +08:00
phys = blk_rq_pos(scmd->request) & 0xffffffff;
if (sector_sz == 4096)
phys >>= 3;
__rq_for_each_bio(bio, scmd->request) {
struct bio_vec iv;
struct bvec_iter iter;
virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
bip_for_each_vec(iv, bio->bi_integrity, iter) {
sdt = kmap_atomic(iv.bv_page)
+ iv.bv_offset;
for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
if (sectors == 0) {
kunmap_atomic(sdt);
return;
}
if (be32_to_cpu(sdt->ref_tag) == phys)
sdt->ref_tag = cpu_to_be32(virt);
virt++;
phys++;
sectors--;
}
kunmap_atomic(sdt);
}
}
}