From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
This patch adds support for 4096, 2048 and 1024 byte block_size / sector conversion
from incoming struct se_task->task_lba from native TCM SCSI sector size into our
the iblock_map_task_SG() caller. This is required as for each TCM struct se_task ->
struct bio I/O descriptor will always need to be assuming 512-byte sectors into
Linux/Block for submit_bio(), so when iblock_map_task_SG() is called we increment
block_lba in 512 byte units from sg->length for passing into iblock_get_bio() ->
struct bio->bi_sector assignment.
So far this patch has been tested with TCM_Loop virtual SCSI device on top of
IBLOCK+scsi_debug using non 512-byte block_sizes on x86 HVM.
Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/target_core_iblock.c | 37 ++++++++++++++++++++++++++--------
1 files changed, 28 insertions(+), 9 deletions(-)
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 1a0552f..d10930e 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -757,11 +757,12 @@ static void iblock_bio_destructor(struct bio *bio)
bio_free(bio, ib_dev->ibd_bio_set);
}
-static struct bio *iblock_get_bio(struct se_task *task,
+static struct bio *iblock_get_bio(
+ struct se_task *task,
struct iblock_req *ib_req,
struct iblock_dev *ib_dev,
int *ret,
- u64 lba,
+ sector_t lba,
u32 sg_num)
{
struct bio *bio;
@@ -792,18 +793,36 @@ static struct bio *iblock_get_bio(struct se_task *task,
static int iblock_map_task_SG(struct se_task *task)
{
+ struct se_cmd *cmd = task->task_se_cmd;
+ struct se_device *dev = SE_DEV(cmd);
struct iblock_dev *ib_dev = (struct iblock_dev *) task->se_dev->dev_ptr;
struct iblock_req *ib_req = (struct iblock_req *) task->transport_req;
struct bio *bio = NULL, *hbio = NULL, *tbio = NULL;
struct scatterlist *sg = task->task_sg;
int ret = 0;
u32 i, sg_num = task->task_sg_num;
- u64 lba = task->task_lba;
+ sector_t block_lba;
+ /*
+ * Do starting conversion up from non 512-byte blocksize with
+ * struct se_task SCSI blocksize into Linux/Block 512 units for BIO.
+ */
+ if (DEV_ATTRIB(dev)->block_size == 4096)
+ block_lba = (task->task_lba << 3);
+ else if (DEV_ATTRIB(dev)->block_size == 2048)
+ block_lba = (task->task_lba << 2);
+ else if (DEV_ATTRIB(dev)->block_size == 1024)
+ block_lba = (task->task_lba << 1);
+ else if (DEV_ATTRIB(dev)->block_size == 512)
+ block_lba = task->task_lba;
+ else {
+ printk(KERN_ERR "Unsupported SCSI -> BLOCK LBA conversion:"
+ " %u\n", DEV_ATTRIB(dev)->block_size);
+ return PYX_TRANSPORT_LU_COMM_FAILURE;
+ }
atomic_set(&ib_req->ib_bio_cnt, 0);
- bio = iblock_get_bio(task, ib_req, ib_dev, &ret,
- task->task_lba, sg_num);
+ bio = iblock_get_bio(task, ib_req, ib_dev, &ret, block_lba, sg_num);
if (!(bio))
return ret;
@@ -832,7 +851,7 @@ again:
bio->bi_vcnt);
bio = iblock_get_bio(task, ib_req, ib_dev, &ret,
- lba, sg_num);
+ block_lba, sg_num);
if (!(bio))
goto fail;
@@ -841,13 +860,13 @@ again:
" list, Going to again\n", bio);
goto again;
}
-
- lba += sg[i].length >> IBLOCK_LBA_SHIFT;
+ /* Always in 512 byte units for Linux/Block */
+ block_lba += sg[i].length >> IBLOCK_LBA_SHIFT;
sg_num--;
DEBUG_IBLOCK("task: %p bio-add_page() passed!, decremented"
" sg_num to %u\n", task, sg_num);
DEBUG_IBLOCK("task: %p bio_add_page() passed!, increased lba"
- " to %llu\n", task, lba);
+ " to %llu\n", task, block_lba);
DEBUG_IBLOCK("task: %p bio_add_page() passed!, bio->bi_vcnt:"
" %u\n", task, bio->bi_vcnt);
}
--
1.5.6.5
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