diff options
author | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-01-08 02:44:57 +0400 |
---|---|---|
committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-01-18 13:53:12 +0400 |
commit | 41861fa831afd4b5006f0042e1f701360330351e (patch) | |
tree | 57818e9a7b160cd6b0bb17e74deb9565d238bcc5 /drivers/target/target_core_sbc.c | |
parent | 499bf77b0169605a23c38351e3849066fe696877 (diff) | |
download | linux-41861fa831afd4b5006f0042e1f701360330351e.tar.xz |
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: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'drivers/target/target_core_sbc.c')
-rw-r--r-- | drivers/target/target_core_sbc.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index 91a92f354e9f..26e8bfb27787 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -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 @@ err: 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); |