target/rd: Add DIF protection into rd_execute_rw

This patch adds support for DIF protection into rd_execute_rw() code
for WRITE/READ I/O using sbc_dif_verify_[write,read]() logic.

It also adds rd_get_prot_table() for locating protection SGLs
assoicated with the ramdisk backend device.

v2 changes:
  - Make rd_execute_rw() to u32 sectors count instead of sector_t
  - Drop SCF_PROT usage

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>
This commit is contained in:
Nicholas Bellinger 2014-01-08 12:06:30 +00:00
parent d7e8eb5d92
commit 6e611119b1

View file

@ -356,6 +356,26 @@ static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page)
return NULL;
}
static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page)
{
struct rd_dev_sg_table *sg_table;
u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE /
sizeof(struct scatterlist));
i = page / sg_per_table;
if (i < rd_dev->sg_prot_count) {
sg_table = &rd_dev->sg_prot_array[i];
if ((sg_table->page_start_offset <= page) &&
(sg_table->page_end_offset >= page))
return sg_table;
}
pr_err("Unable to locate struct prot rd_dev_sg_table for page: %u\n",
page);
return NULL;
}
static sense_reason_t
rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
enum dma_data_direction data_direction)
@ -370,6 +390,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
u32 rd_page;
u32 src_len;
u64 tmp;
sense_reason_t rc;
if (dev->rd_flags & RDF_NULLIO) {
target_complete_cmd(cmd, SAM_STAT_GOOD);
@ -392,6 +413,28 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
data_direction == DMA_FROM_DEVICE ? "Read" : "Write",
cmd->t_task_lba, rd_size, rd_page, rd_offset);
if (cmd->prot_type && data_direction == DMA_TO_DEVICE) {
struct rd_dev_sg_table *prot_table;
struct scatterlist *prot_sg;
u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
u32 prot_offset, prot_page;
tmp = cmd->t_task_lba * se_dev->prot_length;
prot_offset = do_div(tmp, PAGE_SIZE);
prot_page = tmp;
prot_table = rd_get_prot_table(dev, prot_page);
if (!prot_table)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors, 0,
prot_sg, prot_offset);
if (rc)
return rc;
}
src_len = PAGE_SIZE - rd_offset;
sg_miter_start(&m, sgl, sgl_nents,
data_direction == DMA_FROM_DEVICE ?
@ -453,6 +496,28 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
}
sg_miter_stop(&m);
if (cmd->prot_type && data_direction == DMA_FROM_DEVICE) {
struct rd_dev_sg_table *prot_table;
struct scatterlist *prot_sg;
u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
u32 prot_offset, prot_page;
tmp = cmd->t_task_lba * se_dev->prot_length;
prot_offset = do_div(tmp, PAGE_SIZE);
prot_page = tmp;
prot_table = rd_get_prot_table(dev, prot_page);
if (!prot_table)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset];
rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0,
prot_sg, prot_offset);
if (rc)
return rc;
}
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}