diff options
| author | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-04-02 14:19:09 -0700 |
|---|---|---|
| committer | Nicholas Bellinger <nab@linux-iscsi.org> | 2014-04-07 01:48:56 -0700 |
| commit | 66a3d5bc47d2973820816226e957db9e85285455 (patch) | |
| tree | 9af631288b3701492f458d879516a4cda7e658cb | |
| parent | 2d3359832513ac62a8bd6d2bffbb2c5bdd29aad3 (diff) | |
target/sbc: Add sbc_dif_generate software emulation
This patch adds WRITE_INSERT emulation within target-core
using TYPE1 / TYPE3 PI modes in sbc_dif_generate() code.
This is useful in order for existing legacy fabrics that do not
support protection offloads to interact with backend devices that
currently have T10 PI enabled.
v2 changes:
- Rename to sbc_dif_generate() (Sagi)
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
| -rw-r--r-- | drivers/target/target_core_sbc.c | 44 | ||||
| -rw-r--r-- | include/target/target_core_backend.h | 1 |
2 files changed, 45 insertions, 0 deletions
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index f2d73dd4f9a..cc8c0ba5393 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -1096,6 +1096,50 @@ err: } EXPORT_SYMBOL(sbc_execute_unmap); +void +sbc_dif_generate(struct se_cmd *cmd) +{ + struct se_device *dev = cmd->se_dev; + struct se_dif_v1_tuple *sdt; + struct scatterlist *dsg, *psg = cmd->t_prot_sg; + sector_t sector = cmd->t_task_lba; + void *daddr, *paddr; + int i, j, offset = 0; + + 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; + sdt->guard_tag = cpu_to_be16(crc_t10dif(daddr + j, + dev->dev_attrib.block_size)); + if (dev->dev_attrib.pi_prot_type == TARGET_DIF_TYPE1_PROT) + sdt->ref_tag = cpu_to_be32(sector & 0xffffffff); + sdt->app_tag = 0; + + pr_debug("DIF WRITE INSERT 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)); + + sector++; + offset += sizeof(struct se_dif_v1_tuple); + } + + kunmap_atomic(paddr); + kunmap_atomic(daddr); + } +} + 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) diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h index 7020e33e742..0a36c6cb93b 100644 --- a/include/target/target_core_backend.h +++ b/include/target/target_core_backend.h @@ -73,6 +73,7 @@ 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); +void sbc_dif_generate(struct se_cmd *); 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, |