static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, dif_verify dif_verify)
{
struct se_device *se_dev = cmd->se_dev;
struct rd_dev *dev = RD_DEV(se_dev);
struct rd_dev_sg_table *prot_table;
bool need_to_release = false;
struct scatterlist *prot_sg;
u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size;
u32 prot_offset, prot_page;
u32 prot_npages __maybe_unused;
u64 tmp;
sense_reason_t rc = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
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];
#ifndef CONFIG_ARCH_HAS_SG_CHAIN
prot_npages = DIV_ROUND_UP(prot_offset + sectors * se_dev->prot_length,
PAGE_SIZE);
/*
* Allocate temporaly contiguous scatterlist entries if prot pages
* straddles multiple scatterlist tables.
*/
if (prot_table->page_end_offset < prot_page + prot_npages - 1) {
int i;
prot_sg = kcalloc(prot_npages, sizeof(*prot_sg), GFP_KERNEL);
if (!prot_sg)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
need_to_release = true;
sg_init_table(prot_sg, prot_npages);
for (i = 0; i < prot_npages; i++) {
if (prot_page + i > prot_table->page_end_offset) {
prot_table = rd_get_prot_table(dev,
prot_page + i);
if (!prot_table) {
kfree(prot_sg);
return rc;
}
sg_unmark_end(&prot_sg[i - 1]);
}
prot_sg[i] = prot_table->sg_table[prot_page + i -
prot_table->page_start_offset];
}
}
#endif /* !CONFIG_ARCH_HAS_SG_CHAIN */
rc = dif_verify(cmd, cmd->t_task_lba, sectors, 0, prot_sg, prot_offset);
if (need_to_release)
kfree(prot_sg);
return rc;
}
static sense_reason_t
rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
enum dma_data_direction data_direction)
{
struct se_device *se_dev = cmd->se_dev;
struct rd_dev *dev = RD_DEV(se_dev);
struct rd_dev_sg_table *table;
struct scatterlist *rd_sg;
struct sg_mapping_iter m;
u32 rd_offset;
u32 rd_size;
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);
return 0;
}
tmp = cmd->t_task_lba * se_dev->dev_attrib.block_size;
rd_offset = do_div(tmp, PAGE_SIZE);
rd_page = tmp;
rd_size = cmd->data_length;
table = rd_get_sg_table(dev, rd_page);
if (!table)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
rd_sg = &table->sg_table[rd_page - table->page_start_offset];
pr_debug("RD[%u]: %s LBA: %llu, Size: %u Page: %u, Offset: %u\n",
dev->rd_dev_id,
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 ?
SG_MITER_TO_SG : SG_MITER_FROM_SG);
while (rd_size) {
u32 len;
void *rd_addr;
sg_miter_next(&m);
if (!(u32)m.length) {
pr_debug("RD[%u]: invalid sgl %p len %zu\n",
dev->rd_dev_id, m.addr, m.length);
sg_miter_stop(&m);
return TCM_INCORRECT_AMOUNT_OF_DATA;
}
len = min((u32)m.length, src_len);
if (len > rd_size) {
pr_debug("RD[%u]: size underrun page %d offset %d "
"size %d\n", dev->rd_dev_id,
rd_page, rd_offset, rd_size);
len = rd_size;
}
m.consumed = len;
rd_addr = sg_virt(rd_sg) + rd_offset;
if (data_direction == DMA_FROM_DEVICE)
memcpy(m.addr, rd_addr, len);
else
memcpy(rd_addr, m.addr, len);
rd_size -= len;
if (!rd_size)
continue;
src_len -= len;
if (src_len) {
rd_offset += len;
continue;
}
/* rd page completed, next one please */
rd_page++;
rd_offset = 0;
src_len = PAGE_SIZE;
if (rd_page <= table->page_end_offset) {
rd_sg++;
continue;
}
table = rd_get_sg_table(dev, rd_page);
if (!table) {
sg_miter_stop(&m);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
/* since we increment, the first sg entry is correct */
rd_sg = table->sg_table;
}
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;
}