[SCSI] sd: Support for SCSI disk (SBC) Data Integrity Field (af55ff67) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/scsi/Kconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -63,6 +63,7 @@ comment "SCSI support type (disk, tape, CD-ROM)"
		config BLK_DEV_SD
		tristate "SCSI disk support"
		depends on SCSI
		select CRC_T10DIF
		---help---
		If you want to use SCSI hard disks, Fibre Channel disks,
		Serial ATA (SATA) or Parallel ATA (PATA) hard disks,

drivers/scsi/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -151,6 +151,8 @@ scsi_mod-$(CONFIG_SCSI_PROC_FS) += scsi_proc.o
		scsi_tgt-y += scsi_tgt_lib.o scsi_tgt_if.o

		sd_mod-objs := sd.o
		sd_mod-$(CONFIG_BLK_DEV_INTEGRITY) += sd_dif.o

		sr_mod-objs := sr.o sr_ioctl.o sr_vendor.o
		ncr53c8xx-flags-$(CONFIG_SCSI_ZALON) \
		:= -DCONFIG_NCR53C8XX_PREFETCH -DSCSI_NCR_BIG_ENDIAN \

drivers/scsi/sd.c

+81 −40

Original line number	Diff line number	Diff line
		@@ -373,6 +373,7 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		struct scsi_cmnd *SCpnt;
		struct scsi_device *sdp = q->queuedata;
		struct gendisk *disk = rq->rq_disk;
		struct scsi_disk *sdkp;
		sector_t block = rq->sector;
		unsigned int this_count = rq->nr_sectors;
		unsigned int timeout = sdp->timeout;
		@@ -389,6 +390,7 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		if (ret != BLKPREP_OK)
		goto out;
		SCpnt = rq->special;
		sdkp = scsi_disk(disk);

		/* from here on until we're complete, any goto out
		* is used for a killable error condition */
		@@ -478,6 +480,11 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		}
		SCpnt->cmnd[0] = WRITE_6;
		SCpnt->sc_data_direction = DMA_TO_DEVICE;

		if (blk_integrity_rq(rq) &&
		sd_dif_prepare(rq, block, sdp->sector_size) == -EIO)
		goto out;

		} else if (rq_data_dir(rq) == READ) {
		SCpnt->cmnd[0] = READ_6;
		SCpnt->sc_data_direction = DMA_FROM_DEVICE;
		@@ -492,6 +499,10 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		"writing" : "reading", this_count,
		rq->nr_sectors));

		/* Set RDPROTECT/WRPROTECT if disk is formatted with DIF */
		if (scsi_host_dif_capable(sdp->host, sdkp->protection_type))
		SCpnt->cmnd[1] = 1 << 5;
		else
		SCpnt->cmnd[1] = 0;

		if (block > 0xffffffff) {
		@@ -511,6 +522,7 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		SCpnt->cmnd[13] = (unsigned char) this_count & 0xff;
		SCpnt->cmnd[14] = SCpnt->cmnd[15] = 0;
		} else if ((this_count > 0xff) \|\| (block > 0x1fffff) \|\|
		scsi_device_protection(SCpnt->device) \|\|
		SCpnt->device->use_10_for_rw) {
		if (this_count > 0xffff)
		this_count = 0xffff;
		@@ -545,6 +557,10 @@ static int sd_prep_fn(struct request_queue q, struct request rq)
		}
		SCpnt->sdb.length = this_count * sdp->sector_size;

		/* If DIF or DIX is enabled, tell HBA how to handle request */
		if (sdkp->protection_type \|\| scsi_prot_sg_count(SCpnt))
		sd_dif_op(SCpnt, sdkp->protection_type, scsi_prot_sg_count(SCpnt));

		/*
		* We shouldn't disconnect in the middle of a sector, so with a dumb
		* host adapter, it's safe to assume that we can at least transfer
		@@ -939,6 +955,48 @@ static struct block_device_operations sd_fops = {
		.revalidate_disk = sd_revalidate_disk,
		};

		static unsigned int sd_completed_bytes(struct scsi_cmnd *scmd)
		{
		u64 start_lba = scmd->request->sector;
		u64 end_lba = scmd->request->sector + (scsi_bufflen(scmd) / 512);
		u64 bad_lba;
		int info_valid;

		if (!blk_fs_request(scmd->request))
		return 0;

		info_valid = scsi_get_sense_info_fld(scmd->sense_buffer,
		SCSI_SENSE_BUFFERSIZE,
		&bad_lba);
		if (!info_valid)
		return 0;

		if (scsi_bufflen(scmd) <= scmd->device->sector_size)
		return 0;

		if (scmd->device->sector_size < 512) {
		/* only legitimate sector_size here is 256 */
		start_lba <<= 1;
		end_lba <<= 1;
		} else {
		/* be careful ... don't want any overflows */
		u64 factor = scmd->device->sector_size / 512;
		do_div(start_lba, factor);
		do_div(end_lba, factor);
		}

		/* The bad lba was reported incorrectly, we have no idea where
		* the error is.
		*/
		if (bad_lba < start_lba \|\| bad_lba >= end_lba)
		return 0;

		/* This computation should always be done in terms of
		* the resolution of the device's medium.
		*/
		return (bad_lba - start_lba) * scmd->device->sector_size;
		}

		/**
		* sd_done - bottom half handler: called when the lower level
		* driver has completed (successfully or otherwise) a scsi command.
		@@ -949,15 +1007,10 @@ static struct block_device_operations sd_fops = {
		static int sd_done(struct scsi_cmnd *SCpnt)
		{
		int result = SCpnt->result;
		unsigned int xfer_size = scsi_bufflen(SCpnt);
		unsigned int good_bytes = result ? 0 : xfer_size;
		u64 start_lba = SCpnt->request->sector;
		u64 end_lba = SCpnt->request->sector + (xfer_size / 512);
		u64 bad_lba;
		unsigned int good_bytes = result ? 0 : scsi_bufflen(SCpnt);
		struct scsi_sense_hdr sshdr;
		int sense_valid = 0;
		int sense_deferred = 0;
		int info_valid;

		if (result) {
		sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
		@@ -982,36 +1035,7 @@ static int sd_done(struct scsi_cmnd *SCpnt)
		switch (sshdr.sense_key) {
		case HARDWARE_ERROR:
		case MEDIUM_ERROR:
		if (!blk_fs_request(SCpnt->request))
		goto out;
		info_valid = scsi_get_sense_info_fld(SCpnt->sense_buffer,
		SCSI_SENSE_BUFFERSIZE,
		&bad_lba);
		if (!info_valid)
		goto out;
		if (xfer_size <= SCpnt->device->sector_size)
		goto out;
		if (SCpnt->device->sector_size < 512) {
		/* only legitimate sector_size here is 256 */
		start_lba <<= 1;
		end_lba <<= 1;
		} else {
		/* be careful ... don't want any overflows */
		u64 factor = SCpnt->device->sector_size / 512;
		do_div(start_lba, factor);
		do_div(end_lba, factor);
		}

		if (bad_lba < start_lba \|\| bad_lba >= end_lba)
		/* the bad lba was reported incorrectly, we have
		* no idea where the error is
		*/
		goto out;

		/* This computation should always be done in terms of
		* the resolution of the device's medium.
		*/
		good_bytes = (bad_lba - start_lba)*SCpnt->device->sector_size;
		good_bytes = sd_completed_bytes(SCpnt);
		break;
		case RECOVERED_ERROR:
		case NO_SENSE:
		@@ -1021,10 +1045,23 @@ static int sd_done(struct scsi_cmnd *SCpnt)
		scsi_print_sense("sd", SCpnt);
		SCpnt->result = 0;
		memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
		good_bytes = xfer_size;
		good_bytes = scsi_bufflen(SCpnt);
		break;
		case ABORTED_COMMAND:
		if (sshdr.asc == 0x10) { /* DIF: Disk detected corruption */
		scsi_print_result(SCpnt);
		scsi_print_sense("sd", SCpnt);
		good_bytes = sd_completed_bytes(SCpnt);
		}
		break;
		case ILLEGAL_REQUEST:
		if (SCpnt->device->use_10_for_rw &&
		if (sshdr.asc == 0x10) { /* DIX: HBA detected corruption */
		scsi_print_result(SCpnt);
		scsi_print_sense("sd", SCpnt);
		good_bytes = sd_completed_bytes(SCpnt);
		}
		if (!scsi_device_protection(SCpnt->device) &&
		SCpnt->device->use_10_for_rw &&
		(SCpnt->cmnd[0] == READ_10 \|\|
		SCpnt->cmnd[0] == WRITE_10))
		SCpnt->device->use_10_for_rw = 0;
		@@ -1037,6 +1074,9 @@ static int sd_done(struct scsi_cmnd *SCpnt)
		break;
		}
		out:
		if (rq_data_dir(SCpnt->request) == READ && scsi_prot_sg_count(SCpnt))
		sd_dif_complete(SCpnt, good_bytes);

		return good_bytes;
		}

		@@ -1826,6 +1866,7 @@ static int sd_probe(struct device *dev)

		dev_set_drvdata(dev, sdkp);
		add_disk(gd);
		sd_dif_config_host(sdkp);

		sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",
		sdp->removable ? "removable " : "");

drivers/scsi/sd.h

+25 −0

Original line number	Diff line number	Diff line
		@@ -82,4 +82,29 @@ enum sd_dif_target_protection_types {
		SD_DIF_TYPE3_PROTECTION = 0x3,
		};

		/*
		* Data Integrity Field tuple.
		*/
		struct sd_dif_tuple {
		__be16 guard_tag; /* Checksum */
		__be16 app_tag; /* Opaque storage */
		__be32 ref_tag; /* Target LBA or indirect LBA */
		};

		#if defined(CONFIG_BLK_DEV_INTEGRITY)

		extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int);
		extern void sd_dif_config_host(struct scsi_disk *);
		extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);
		extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);

		#else /* CONFIG_BLK_DEV_INTEGRITY */

		#define sd_dif_op(a, b, c) do { } while (0)
		#define sd_dif_config_host(a) do { } while (0)
		#define sd_dif_prepare(a, b, c) (0)
		#define sd_dif_complete(a, b) (0)

		#endif /* CONFIG_BLK_DEV_INTEGRITY */

		#endif /* _SCSI_DISK_H */

drivers/scsi/sd_dif.c

0 → 100644

+538 −0

Original line number	Diff line number	Diff line
		/*
		* 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;

		/* Bad ref tag received from disk */
		if (sdt->ref_tag == 0xffffffff) {
		printk(KERN_ERR
		"%s: bad phys ref tag on sector %lu\n",
		bix->disk_name, (unsigned long)sector);
		return -EIO;
		}

		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;
		char *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;
		char *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;
		char *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;
		char *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;

		/* If this HBA doesn't support DIX, resort to normal I/O or DIF */
		if (scsi_host_dix_capable(sdp->host, type) == 0) {

		if (type == SD_DIF_TYPE0_PROTECTION)
		return;

		if (scsi_host_dif_capable(sdp->host, type) == 0) {
		sd_printk(KERN_INFO, sdkp, "Type %d protection " \
		"unsupported by HBA. Disabling DIF.\n", type);
		sdkp->protection_type = 0;
		return;
		}

		sd_printk(KERN_INFO, sdkp, "Enabling DIF Type %d protection\n",
		type);

		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_INFO, sdkp,
		"Enabling %s integrity protection\n", disk->integrity->name);

		/* Signal to block layer that we support sector tagging */
		if (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_INFO, sdkp, "DIF application tag size %u\n",
		disk->integrity->tag_size);
		}
		}

		/*
		* DIF DMA operation magic decoder ring.
		*/
		void sd_dif_op(struct scsi_cmnd *scmd, unsigned int dif, unsigned int dix)
		{
		int csum_convert, prot_op;

		prot_op = 0;

		/* Convert checksum? */
		if (scsi_host_get_guard(scmd->device->host) != SHOST_DIX_GUARD_CRC)
		csum_convert = 1;
		else
		csum_convert = 0;

		switch (scmd->cmnd[0]) {
		case READ_10:
		case READ_12:
		case READ_16:
		if (dif && dix)
		if (csum_convert)
		prot_op = SCSI_PROT_READ_CONVERT;
		else
		prot_op = SCSI_PROT_READ_PASS;
		else if (dif && !dix)
		prot_op = SCSI_PROT_READ_STRIP;
		else if (!dif && dix)
		prot_op = SCSI_PROT_READ_INSERT;

		break;

		case WRITE_10:
		case WRITE_12:
		case WRITE_16:
		if (dif && dix)
		if (csum_convert)
		prot_op = SCSI_PROT_WRITE_CONVERT;
		else
		prot_op = SCSI_PROT_WRITE_PASS;
		else if (dif && !dix)
		prot_op = SCSI_PROT_WRITE_INSERT;
		else if (!dif && dix)
		prot_op = SCSI_PROT_WRITE_STRIP;

		break;
		}

		scsi_set_prot_op(scmd, prot_op);
		scsi_set_prot_type(scmd, dif);
		}

		/*
		* 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.
		*/
		int 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;
		unsigned int i, j;
		u32 phys, virt;

		/* Already remapped? */
		if (rq->cmd_flags & REQ_INTEGRITY)
		return 0;

		sdkp = rq->bio->bi_bdev->bd_disk->private_data;

		if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
		return 0;

		rq->cmd_flags \|= REQ_INTEGRITY;
		phys = hw_sector & 0xffffffff;

		__rq_for_each_bio(bio, rq) {
		struct bio_vec *iv;

		virt = bio->bi_integrity->bip_sector & 0xffffffff;

		bip_for_each_vec(iv, bio->bi_integrity, i) {
		sdt = kmap_atomic(iv->bv_page, KM_USER0)
		+ iv->bv_offset;

		for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {

		if (be32_to_cpu(sdt->ref_tag) != virt)
		goto error;

		sdt->ref_tag = cpu_to_be32(phys);
		virt++;
		phys++;
		}

		kunmap_atomic(sdt, KM_USER0);
		}
		}

		return 0;

		error:
		kunmap_atomic(sdt, KM_USER0);
		sd_printk(KERN_ERR, sdkp, "%s: virt %u, phys %u, ref %u\n",
		__func__, virt, phys, be32_to_cpu(sdt->ref_tag));

		return -EIO;
		}

		/*
		* 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 i, 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 = scmd->request->sector & 0xffffffff;
		if (sector_sz == 4096)
		phys >>= 3;

		__rq_for_each_bio(bio, scmd->request) {
		struct bio_vec *iv;

		virt = bio->bi_integrity->bip_sector & 0xffffffff;

		bip_for_each_vec(iv, bio->bi_integrity, i) {
		sdt = kmap_atomic(iv->bv_page, KM_USER0)
		+ iv->bv_offset;

		for (j = 0 ; j < iv->bv_len ; j += tuple_sz, sdt++) {

		if (sectors == 0) {
		kunmap_atomic(sdt, KM_USER0);
		return;
		}

		if (be32_to_cpu(sdt->ref_tag) != phys &&
		sdt->app_tag != 0xffff)
		sdt->ref_tag = 0xffffffff; /* Bad ref */
		else
		sdt->ref_tag = cpu_to_be32(virt);

		virt++;
		phys++;
		sectors--;
		}

		kunmap_atomic(sdt, KM_USER0);
		}
		}
		}