[linux-2.6-block.git] / drivers / scsi / sd_dif.c

/*
 * 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 seed = bix->seed;
	unsigned int i;

	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
		sdt->guard_tag = fn(buf, bix->interval);
		sdt->ref_tag = cpu_to_be32(seed & 0xffffffff);
		sdt->app_tag = 0;

		buf += bix->interval;
		seed++;
	}
}

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 seed = bix->seed;
	unsigned int i;
	__u16 csum;

	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
		/* Unwritten sectors */
		if (sdt->app_tag == 0xffff)
			return 0;

		if (be32_to_cpu(sdt->ref_tag) != (seed & 0xffffffff)) {
			printk(KERN_ERR
			       "%s: ref tag error on sector %lu (rcvd %u)\n",
			       bix->disk_name, (unsigned long)seed,
			       be32_to_cpu(sdt->ref_tag));
			return -EIO;
		}

		csum = fn(buf, bix->interval);

		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)seed,
			       be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
			return -EIO;
		}

		buf += bix->interval;
		seed++;
	}

	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);
}

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,
	.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,
	.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->interval, sdt++) {
		sdt->guard_tag = fn(buf, bix->interval);
		sdt->ref_tag = 0;
		sdt->app_tag = 0;

		buf += bix->interval;
	}
}

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 seed = bix->seed;
	unsigned int i;
	__u16 csum;

	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
		/* Unwritten sectors */
		if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
			return 0;

		csum = fn(buf, bix->interval);

		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)seed,
			       be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
			return -EIO;
		}

		buf += bix->interval;
		seed++;
	}

	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 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,
	.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,
	.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_integrity(bio)->bip_iter.bi_sector & 0xffffffff;

		bip_for_each_vec(iv, bio_integrity(bio), 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;

	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_integrity(bio)->bip_iter.bi_sector & 0xffffffff;

		bip_for_each_vec(iv, bio_integrity(bio), 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);
		}
	}
}
Commit	Line	Data
af55ff67 MP	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
	40	typedef __u16 (csum_fn) (void *, unsigned int);
	41
	42	static __u16 sd_dif_crc_fn(void *data, unsigned int len)
	43	{
	44	return cpu_to_be16(crc_t10dif(data, len));
	45	}
	46
	47	static __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	*/
	56	static 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;
3be91c4a	60	sector_t seed = bix->seed;
af55ff67 MP	61	unsigned int i;
af55ff67 MP	62
3be91c4a MP	63	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
	64	sdt->guard_tag = fn(buf, bix->interval);
	65	sdt->ref_tag = cpu_to_be32(seed & 0xffffffff);
af55ff67 MP	66	sdt->app_tag = 0;
af55ff67 MP	67
3be91c4a MP	68	buf += bix->interval;
3be91c4a MP	69	seed++;
af55ff67 MP	70	}
	71	}
	72
	73	static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
	74	{
	75	sd_dif_type1_generate(bix, sd_dif_crc_fn);
	76	}
	77
	78	static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
	79	{
	80	sd_dif_type1_generate(bix, sd_dif_ip_fn);
	81	}
	82
	83	static 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;
3be91c4a	87	sector_t seed = bix->seed;
af55ff67 MP	88	unsigned int i;
	89	__u16 csum;
	90
3be91c4a	91	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
af55ff67 MP	92	/* Unwritten sectors */
	93	if (sdt->app_tag == 0xffff)
	94	return 0;
	95
3be91c4a	96	if (be32_to_cpu(sdt->ref_tag) != (seed & 0xffffffff)) {
af55ff67 MP	97	printk(KERN_ERR
af55ff67 MP	98	"%s: ref tag error on sector %lu (rcvd %u)\n",
3be91c4a	99	bix->disk_name, (unsigned long)seed,
af55ff67 MP	100	be32_to_cpu(sdt->ref_tag));
	101	return -EIO;
	102	}
	103
3be91c4a	104	csum = fn(buf, bix->interval);
af55ff67 MP	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,
3be91c4a	109	(unsigned long)seed,
af55ff67 MP	110	be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
	111	return -EIO;
	112	}
	113
3be91c4a MP	114	buf += bix->interval;
3be91c4a MP	115	seed++;
af55ff67 MP	116	}
	117
	118	return 0;
	119	}
	120
	121	static 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
	126	static 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
af55ff67 MP	131	static struct blk_integrity dif_type1_integrity_crc = {
	132	.name = "T10-DIF-TYPE1-CRC",
	133	.generate_fn = sd_dif_type1_generate_crc,
	134	.verify_fn = sd_dif_type1_verify_crc,
af55ff67 MP	135	.tuple_size = sizeof(struct sd_dif_tuple),
	136	.tag_size = 0,
	137	};
	138
	139	static struct blk_integrity dif_type1_integrity_ip = {
	140	.name = "T10-DIF-TYPE1-IP",
	141	.generate_fn = sd_dif_type1_generate_ip,
	142	.verify_fn = sd_dif_type1_verify_ip,
af55ff67 MP	143	.tuple_size = sizeof(struct sd_dif_tuple),
	144	.tag_size = 0,
	145	};
	146
	147
	148	/*
	149	* Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
	150	* tag space.
	151	*/
	152	static void sd_dif_type3_generate(struct blk_integrity_exchg bix, csum_fn fn)
	153	{
	154	void *buf = bix->data_buf;
	155	struct sd_dif_tuple *sdt = bix->prot_buf;
	156	unsigned int i;
	157
3be91c4a MP	158	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
3be91c4a MP	159	sdt->guard_tag = fn(buf, bix->interval);
af55ff67 MP	160	sdt->ref_tag = 0;
	161	sdt->app_tag = 0;
	162
3be91c4a	163	buf += bix->interval;
af55ff67 MP	164	}
	165	}
	166
	167	static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
	168	{
	169	sd_dif_type3_generate(bix, sd_dif_crc_fn);
	170	}
	171
	172	static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
	173	{
	174	sd_dif_type3_generate(bix, sd_dif_ip_fn);
	175	}
	176
	177	static int sd_dif_type3_verify(struct blk_integrity_exchg bix, csum_fn fn)
	178	{
	179	void *buf = bix->data_buf;
	180	struct sd_dif_tuple *sdt = bix->prot_buf;
3be91c4a	181	sector_t seed = bix->seed;
af55ff67 MP	182	unsigned int i;
	183	__u16 csum;
	184
3be91c4a	185	for (i = 0 ; i < bix->data_size ; i += bix->interval, sdt++) {
af55ff67 MP	186	/* Unwritten sectors */
	187	if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
	188	return 0;
	189
3be91c4a	190	csum = fn(buf, bix->interval);
af55ff67 MP	191
	192	if (sdt->guard_tag != csum) {
	193	printk(KERN_ERR "%s: guard tag error on sector %lu " \
	194	"(rcvd %04x, data %04x)\n", bix->disk_name,
3be91c4a	195	(unsigned long)seed,
af55ff67 MP	196	be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
	197	return -EIO;
	198	}
	199
3be91c4a MP	200	buf += bix->interval;
3be91c4a MP	201	seed++;
af55ff67 MP	202	}
	203
	204	return 0;
	205	}
	206
	207	static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
	208	{
	209	return sd_dif_type3_verify(bix, sd_dif_crc_fn);
	210	}
	211
	212	static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
	213	{
	214	return sd_dif_type3_verify(bix, sd_dif_ip_fn);
	215	}
	216
af55ff67 MP	217	static struct blk_integrity dif_type3_integrity_crc = {
	218	.name = "T10-DIF-TYPE3-CRC",
	219	.generate_fn = sd_dif_type3_generate_crc,
	220	.verify_fn = sd_dif_type3_verify_crc,
af55ff67 MP	221	.tuple_size = sizeof(struct sd_dif_tuple),
	222	.tag_size = 0,
	223	};
	224
	225	static struct blk_integrity dif_type3_integrity_ip = {
	226	.name = "T10-DIF-TYPE3-IP",
	227	.generate_fn = sd_dif_type3_generate_ip,
	228	.verify_fn = sd_dif_type3_verify_ip,
af55ff67 MP	229	.tuple_size = sizeof(struct sd_dif_tuple),
	230	.tag_size = 0,
	231	};
	232
	233	/*
	234	* Configure exchange of protection information between OS and HBA.
	235	*/
	236	void sd_dif_config_host(struct scsi_disk *sdkp)
	237	{
	238	struct scsi_device *sdp = sdkp->device;
	239	struct gendisk *disk = sdkp->disk;
	240	u8 type = sdkp->protection_type;
9e06688e	241	int dif, dix;
af55ff67	242
9e06688e MP	243	dif = scsi_host_dif_capable(sdp->host, type);
9e06688e MP	244	dix = scsi_host_dix_capable(sdp->host, type);
af55ff67	245
9e06688e MP	246	if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
	247	dif = 0; dix = 1;
	248	}
af55ff67	249
9e06688e	250	if (!dix)
af55ff67	251	return;
af55ff67 MP	252
	253	/* Enable DMA of protection information */
	254	if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
	255	if (type == SD_DIF_TYPE3_PROTECTION)
	256	blk_integrity_register(disk, &dif_type3_integrity_ip);
	257	else
	258	blk_integrity_register(disk, &dif_type1_integrity_ip);
	259	else
	260	if (type == SD_DIF_TYPE3_PROTECTION)
	261	blk_integrity_register(disk, &dif_type3_integrity_crc);
	262	else
	263	blk_integrity_register(disk, &dif_type1_integrity_crc);
	264
cbdc1445	265	sd_printk(KERN_NOTICE, sdkp,
9e06688e	266	"Enabling DIX %s protection\n", disk->integrity->name);
af55ff67 MP	267
af55ff67 MP	268	/* Signal to block layer that we support sector tagging */
9e06688e	269	if (dif && type && sdkp->ATO) {
af55ff67 MP	270	if (type == SD_DIF_TYPE3_PROTECTION)
	271	disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
	272	else
	273	disk->integrity->tag_size = sizeof(u16);
	274
cbdc1445	275	sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
af55ff67 MP	276	disk->integrity->tag_size);
	277	}
	278	}
	279
af55ff67 MP	280	/*
	281	* The virtual start sector is the one that was originally submitted
	282	* by the block layer. Due to partitioning, MD/DM cloning, etc. the
	283	* actual physical start sector is likely to be different. Remap
	284	* protection information to match the physical LBA.
	285	*
	286	* From a protocol perspective there's a slight difference between
	287	* Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
	288	* reference tag is seeded in the CDB. This gives us the potential to
	289	* avoid virt->phys remapping during write. However, at read time we
	290	* don't know whether the virt sector is the same as when we wrote it
	291	* (we could be reading from real disk as opposed to MD/DM device. So
	292	* we always remap Type 2 making it identical to Type 1.
	293	*
	294	* Type 3 does not have a reference tag so no remapping is required.
	295	*/
8c579ab6 MP	296	void sd_dif_prepare(struct request *rq, sector_t hw_sector,
8c579ab6 MP	297	unsigned int sector_sz)
af55ff67 MP	298	{
	299	const int tuple_sz = sizeof(struct sd_dif_tuple);
	300	struct bio *bio;
	301	struct scsi_disk *sdkp;
	302	struct sd_dif_tuple *sdt;
af55ff67 MP	303	u32 phys, virt;
af55ff67 MP	304
af55ff67 MP	305	sdkp = rq->bio->bi_bdev->bd_disk->private_data;
	306
	307	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
8c579ab6	308	return;
af55ff67	309
af55ff67 MP	310	phys = hw_sector & 0xffffffff;
	311
	312	__rq_for_each_bio(bio, rq) {
d57a5f7c KO	313	struct bio_vec iv;
	314	struct bvec_iter iter;
	315	unsigned int j;
af55ff67	316
495d2b38 MP	317	/* Already remapped? */
	318	if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
	319	break;
	320
180b2f95	321	virt = bio_integrity(bio)->bip_iter.bi_sector & 0xffffffff;
af55ff67	322
180b2f95	323	bip_for_each_vec(iv, bio_integrity(bio), iter) {
d57a5f7c KO	324	sdt = kmap_atomic(iv.bv_page)
d57a5f7c KO	325	+ iv.bv_offset;
af55ff67	326
d57a5f7c	327	for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
af55ff67	328
8c579ab6 MP	329	if (be32_to_cpu(sdt->ref_tag) == virt)
8c579ab6 MP	330	sdt->ref_tag = cpu_to_be32(phys);
af55ff67	331
af55ff67 MP	332	virt++;
	333	phys++;
	334	}
	335
77dfce07	336	kunmap_atomic(sdt);
af55ff67	337	}
495d2b38	338
9354f1b8	339	bio->bi_flags \|= (1 << BIO_MAPPED_INTEGRITY);
af55ff67	340	}
af55ff67 MP	341	}
	342
	343	/*
	344	* Remap physical sector values in the reference tag to the virtual
	345	* values expected by the block layer.
	346	*/
	347	void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
	348	{
	349	const int tuple_sz = sizeof(struct sd_dif_tuple);
	350	struct scsi_disk *sdkp;
	351	struct bio *bio;
	352	struct sd_dif_tuple *sdt;
d57a5f7c	353	unsigned int j, sectors, sector_sz;
af55ff67 MP	354	u32 phys, virt;
	355
	356	sdkp = scsi_disk(scmd->request->rq_disk);
	357
	358	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION \|\| good_bytes == 0)
	359	return;
	360
	361	sector_sz = scmd->device->sector_size;
	362	sectors = good_bytes / sector_sz;
	363
83096ebf	364	phys = blk_rq_pos(scmd->request) & 0xffffffff;
af55ff67 MP	365	if (sector_sz == 4096)
	366	phys >>= 3;
	367
	368	__rq_for_each_bio(bio, scmd->request) {
d57a5f7c KO	369	struct bio_vec iv;
d57a5f7c KO	370	struct bvec_iter iter;
af55ff67	371
180b2f95	372	virt = bio_integrity(bio)->bip_iter.bi_sector & 0xffffffff;
af55ff67	373
180b2f95	374	bip_for_each_vec(iv, bio_integrity(bio), iter) {
d57a5f7c KO	375	sdt = kmap_atomic(iv.bv_page)
d57a5f7c KO	376	+ iv.bv_offset;
af55ff67	377
d57a5f7c	378	for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
af55ff67 MP	379
af55ff67 MP	380	if (sectors == 0) {
77dfce07	381	kunmap_atomic(sdt);
af55ff67 MP	382	return;
	383	}
	384
8c579ab6	385	if (be32_to_cpu(sdt->ref_tag) == phys)
af55ff67 MP	386	sdt->ref_tag = cpu_to_be32(virt);
	387
	388	virt++;
	389	phys++;
	390	sectors--;
	391	}
	392
77dfce07	393	kunmap_atomic(sdt);
af55ff67 MP	394	}
	395	}
	396	}
	397