Commit 41861fa8 authored by Nicholas Bellinger's avatar Nicholas Bellinger

target/sbc: Add DIF TYPE1+TYPE3 read/write verify emulation

This patch adds support for DIF read/write verify emulation
for TARGET_DIF_TYPE1_PROT + TARGET_DIF_TYPE3_PROT operation.

This includes sbc_dif_verify_write() + sbc_dif_verify_read()
calls accessable by backend drivers to perform DIF verify
for SGL based data and protection information.

Also included is sbc_dif_copy_prot() logic to copy protection
information to/from backend provided protection SGLs.

Based on scsi_debug.c DIF TYPE1+TYPE3 emulation.

v2 changes:
  - Select CRC_T10DIF for TARGET_CORE in Kconfig (Fengguang)
  - Drop IP checksum logic from sbc_dif_v1_verify (MKP)
  - Fix offset on app_tag = 0xffff in sbc_dif_verify_read()

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
parent 499bf77b
......@@ -3,6 +3,7 @@ menuconfig TARGET_CORE
tristate "Generic Target Core Mod (TCM) and ConfigFS Infrastructure"
depends on SCSI && BLOCK
select CONFIGFS_FS
select CRC_T10DIF
default n
help
Say Y or M here to enable the TCM Storage Engine and ConfigFS enabled
......
......@@ -23,6 +23,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ratelimit.h>
#include <linux/crc-t10dif.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
#include <scsi/scsi_tcq.h>
......@@ -1024,3 +1025,180 @@ sbc_execute_unmap(struct se_cmd *cmd,
return ret;
}
EXPORT_SYMBOL(sbc_execute_unmap);
static sense_reason_t
sbc_dif_v1_verify(struct se_device *dev, struct se_dif_v1_tuple *sdt,
const void *p, sector_t sector, unsigned int ei_lba)
{
int block_size = dev->dev_attrib.block_size;
__be16 csum;
csum = cpu_to_be16(crc_t10dif(p, block_size));
if (sdt->guard_tag != csum) {
pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
" csum 0x%04x\n", (unsigned long long)sector,
be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
}
if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT &&
be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
" sector MSB: 0x%08x\n", (unsigned long long)sector,
be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
}
if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE2_PROT &&
be32_to_cpu(sdt->ref_tag) != ei_lba) {
pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
" ei_lba: 0x%08x\n", (unsigned long long)sector,
be32_to_cpu(sdt->ref_tag), ei_lba);
return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
}
return 0;
}
static void
sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
struct scatterlist *sg, int sg_off)
{
struct se_device *dev = cmd->se_dev;
struct scatterlist *psg;
void *paddr, *addr;
unsigned int i, len, left;
left = sectors * dev->prot_length;
for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
len = min(psg->length, left);
paddr = kmap_atomic(sg_page(psg)) + psg->offset;
addr = kmap_atomic(sg_page(sg)) + sg_off;
if (read)
memcpy(paddr, addr, len);
else
memcpy(addr, paddr, len);
left -= len;
kunmap_atomic(paddr);
kunmap_atomic(addr);
}
}
sense_reason_t
sbc_dif_verify_write(struct se_cmd *cmd, sector_t start, unsigned int sectors,
unsigned int ei_lba, struct scatterlist *sg, int sg_off)
{
struct se_device *dev = cmd->se_dev;
struct se_dif_v1_tuple *sdt;
struct scatterlist *dsg, *psg = cmd->t_prot_sg;
sector_t sector = start;
void *daddr, *paddr;
int i, j, offset = 0;
sense_reason_t rc;
for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
paddr = kmap_atomic(sg_page(psg)) + psg->offset;
for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
if (offset >= psg->length) {
kunmap_atomic(paddr);
psg = sg_next(psg);
paddr = kmap_atomic(sg_page(psg)) + psg->offset;
offset = 0;
}
sdt = paddr + offset;
pr_debug("DIF WRITE sector: %llu guard_tag: 0x%04x"
" app_tag: 0x%04x ref_tag: %u\n",
(unsigned long long)sector, sdt->guard_tag,
sdt->app_tag, be32_to_cpu(sdt->ref_tag));
rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
ei_lba);
if (rc) {
kunmap_atomic(paddr);
kunmap_atomic(daddr);
return rc;
}
sector++;
ei_lba++;
offset += sizeof(struct se_dif_v1_tuple);
}
kunmap_atomic(paddr);
kunmap_atomic(daddr);
}
sbc_dif_copy_prot(cmd, sectors, false, sg, sg_off);
return 0;
}
EXPORT_SYMBOL(sbc_dif_verify_write);
sense_reason_t
sbc_dif_verify_read(struct se_cmd *cmd, sector_t start, unsigned int sectors,
unsigned int ei_lba, struct scatterlist *sg, int sg_off)
{
struct se_device *dev = cmd->se_dev;
struct se_dif_v1_tuple *sdt;
struct scatterlist *dsg;
sector_t sector = start;
void *daddr, *paddr;
int i, j, offset = sg_off;
sense_reason_t rc;
for_each_sg(cmd->t_data_sg, dsg, cmd->t_data_nents, i) {
daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
paddr = kmap_atomic(sg_page(sg)) + sg->offset;
for (j = 0; j < dsg->length; j += dev->dev_attrib.block_size) {
if (offset >= sg->length) {
kunmap_atomic(paddr);
sg = sg_next(sg);
paddr = kmap_atomic(sg_page(sg)) + sg->offset;
offset = 0;
}
sdt = paddr + offset;
pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
" app_tag: 0x%04x ref_tag: %u\n",
(unsigned long long)sector, sdt->guard_tag,
sdt->app_tag, be32_to_cpu(sdt->ref_tag));
if (sdt->app_tag == cpu_to_be16(0xffff)) {
sector++;
offset += sizeof(struct se_dif_v1_tuple);
continue;
}
rc = sbc_dif_v1_verify(dev, sdt, daddr + j, sector,
ei_lba);
if (rc) {
kunmap_atomic(paddr);
kunmap_atomic(daddr);
return rc;
}
sector++;
ei_lba++;
offset += sizeof(struct se_dif_v1_tuple);
}
kunmap_atomic(paddr);
kunmap_atomic(daddr);
}
sbc_dif_copy_prot(cmd, sectors, true, sg, sg_off);
return 0;
}
EXPORT_SYMBOL(sbc_dif_verify_read);
......@@ -73,6 +73,10 @@ sense_reason_t sbc_execute_unmap(struct se_cmd *cmd,
sense_reason_t (*do_unmap_fn)(struct se_cmd *cmd, void *priv,
sector_t lba, sector_t nolb),
void *priv);
sense_reason_t sbc_dif_verify_write(struct se_cmd *, sector_t, unsigned int,
unsigned int, struct scatterlist *, int);
sense_reason_t sbc_dif_verify_read(struct se_cmd *, sector_t, unsigned int,
unsigned int, struct scatterlist *, int);
void transport_set_vpd_proto_id(struct t10_vpd *, unsigned char *);
int transport_set_vpd_assoc(struct t10_vpd *, unsigned char *);
......
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