| Message ID | 1401639581-20111-3-git-send-email-sagig@mellanox.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
>>>>> "Sagi" == Sagi Grimberg <sagig@mellanox.com> writes:
Sagi,
Sagi> In various areas of the code, it is assumed that
Sagi> se_cmd-> data_length describes pure data. In case
Sagi> that protection information exists over the wire (protect bits is
Sagi> are on) the target core decrease the protection length from the
Sagi> data length (instead of each transport peeking in the cdb).
I completely agree with the notion of including PI in the transport byte
count.
Why do you open code the transfer length adjustment below?
+ /**
+ * Adjust data_length to include
+ * protection information
+ **/
+ switch (sc->device->sector_size) {
+ case 512:
+ data_len += (data_len >> 9) * 8;
+ break;
+ case 1024:
+ data_len += (data_len >> 10) * 8;
+ break;
+ case 2048:
+ data_len += (data_len >> 11) * 8;
+ break;
+ case 4096:
+ data_len += (data_len >> 12) * 8;
+ break;
+ default:
+ data_len +=
+ (data_len >> ilog2(sc->device->sector_size)) * 8;
+ }
On 6/2/2014 7:54 PM, Martin K. Petersen wrote: >>>>>> "Sagi" == Sagi Grimberg <sagig@mellanox.com> writes: > Sagi, > > Sagi> In various areas of the code, it is assumed that > Sagi> se_cmd-> data_length describes pure data. In case > Sagi> that protection information exists over the wire (protect bits is > Sagi> are on) the target core decrease the protection length from the > Sagi> data length (instead of each transport peeking in the cdb). > > I completely agree with the notion of including PI in the transport byte > count. > > Why do you open code the transfer length adjustment below? Can't say I have a good reason for that. I'll move this logic to scsi_cmnd.h. > > + /** > + * Adjust data_length to include > + * protection information > + **/ > + switch (sc->device->sector_size) { > + case 512: > + data_len += (data_len >> 9) * 8; > + break; > + case 1024: > + data_len += (data_len >> 10) * 8; > + break; > + case 2048: > + data_len += (data_len >> 11) * 8; > + break; > + case 4096: > + data_len += (data_len >> 12) * 8; > + break; > + default: > + data_len += > + (data_len >> ilog2(sc->device->sector_size)) * 8; > + } > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c index c886ad1..9adde8d 100644 --- a/drivers/target/loopback/tcm_loop.c +++ b/drivers/target/loopback/tcm_loop.c @@ -179,7 +179,7 @@ static void tcm_loop_submission_work(struct work_struct *work) struct tcm_loop_hba *tl_hba; struct tcm_loop_tpg *tl_tpg; struct scatterlist *sgl_bidi = NULL; - u32 sgl_bidi_count = 0; + u32 sgl_bidi_count = 0, data_len; int rc; tl_hba = *(struct tcm_loop_hba **)shost_priv(sc->device->host); @@ -213,12 +213,39 @@ static void tcm_loop_submission_work(struct work_struct *work) } - if (!scsi_prot_sg_count(sc) && scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) - se_cmd->prot_pto = true; + data_len = scsi_bufflen(sc); + if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) { + if (!scsi_prot_sg_count(sc)) + se_cmd->prot_pto = true; + else { + /** + * Adjust data_length to include + * protection information + **/ + switch (sc->device->sector_size) { + case 512: + data_len += (data_len >> 9) * 8; + break; + case 1024: + data_len += (data_len >> 10) * 8; + break; + case 2048: + data_len += (data_len >> 11) * 8; + break; + case 4096: + data_len += (data_len >> 12) * 8; + break; + default: + data_len += + (data_len >> ilog2(sc->device->sector_size)) * 8; + } + } + } + rc = target_submit_cmd_map_sgls(se_cmd, tl_nexus->se_sess, sc->cmnd, &tl_cmd->tl_sense_buf[0], tl_cmd->sc->device->lun, - scsi_bufflen(sc), tcm_loop_sam_attr(sc), + data_len, tcm_loop_sam_attr(sc), sc->sc_data_direction, 0, scsi_sglist(sc), scsi_sg_count(sc), sgl_bidi, sgl_bidi_count, diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index e022959..06f8ecd 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -665,8 +665,19 @@ sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb, cmd->prot_type = dev->dev_attrib.pi_prot_type; cmd->prot_length = dev->prot_length * sectors; - pr_debug("%s: prot_type=%d, prot_length=%d prot_op=%d prot_checks=%d\n", - __func__, cmd->prot_type, cmd->prot_length, + + /** + * In case protection information exists over the wire + * we modify command data length to describe pure data. + * The actual transfer length is data length + protection + * length + **/ + if (protect) + cmd->data_length -= cmd->prot_length; + + pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d " + "prot_op=%d prot_checks=%d\n", + __func__, cmd->prot_type, cmd->data_length, cmd->prot_length, cmd->prot_op, cmd->prot_checks); return true;
In various areas of the code, it is assumed that se_cmd->data_length describes pure data. In case that protection information exists over the wire (protect bits is are on) the target core decrease the protection length from the data length (instead of each transport peeking in the cdb). Modify loopback transport to include protection information in the transferred data length (like other scsi transports). Signed-off-by: Sagi Grimberg <sagig@mellanox.com> --- drivers/target/loopback/tcm_loop.c | 35 +++++++++++++++++++++++++++++++---- drivers/target/target_core_sbc.c | 15 +++++++++++++-- 2 files changed, 44 insertions(+), 6 deletions(-)