From: Nicholas Bellinger <n...@linux-iscsi.org>
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.
Cc: Martin K. Petersen <martin.peter...@oracle.com>
Cc: Christoph Hellwig <h...@lst.de>
Cc: Hannes Reinecke <h...@suse.de>
Cc: Sagi Grimberg <sa...@mellanox.com>
Cc: Or Gerlitz <ogerl...@mellanox.com>
Signed-off-by: Nicholas Bellinger <n...@linux-iscsi.org>
---
drivers/target/target_core_rd.c | 67 +++++++++++++++++++++++++++++++++++++++
1 file changed, 67 insertions(+)
diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c
index dd99844..3fd51eb 100644
--- a/drivers/target/target_core_rd.c
+++ b/drivers/target/target_core_rd.c
@@ -363,6 +363,26 @@ 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)
@@ -377,6 +397,7 @@ 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);
@@ -399,6 +420,29 @@ 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->se_cmd_flags & SCF_PROT) && se_dev->dev_attrib.pi_prot_type &&
+ data_direction == DMA_TO_DEVICE) {
+ sector_t sector = cmd->data_length /
se_dev->dev_attrib.block_size;
+ struct rd_dev_sg_table *prot_table;
+ struct scatterlist *prot_sg;
+ 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, sector, 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 ?
@@ -460,6 +504,29 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl,
u32 sgl_nents,
}
sg_miter_stop(&m);
+ if ((cmd->se_cmd_flags & SCF_PROT) && se_dev->dev_attrib.pi_prot_type &&
+ data_direction == DMA_FROM_DEVICE) {
+ sector_t sector = cmd->data_length /
se_dev->dev_attrib.block_size;
+ struct rd_dev_sg_table *prot_table;
+ struct scatterlist *prot_sg;
+ 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, sector, 0,
+ prot_sg, prot_offset);
+ if (rc)
+ return rc;
+ }
+
target_complete_cmd(cmd, SAM_STAT_GOOD);
return 0;
}
