[SCSI] iscsi: Some fixes in preparation for bidirectional support - exp_datasn

This patch fixes handling of expected datasn/r2tsn as received from
target. It is done according to: T10 rfc3720 section 3.2.2.3. Data Sequencing.

. unify expected datasn/r2tsn into one counter
. calculate than check expected datasn/r2tsn. On error print a message
  and fail the request. (TODO use iscsi retransmits)
. remove the FIXME   ;)
. avoid zero length memset

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index deae90a56a0d..61e069206ac5 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -99,7 +99,6 @@ struct iscsi_cmd_task {
          */
         struct iscsi_cmd        *hdr;
         int                     itt;            /* this ITT */
-        int                     datasn;         /* DataSN */
 
         uint32_t                unsol_datasn;
         int                     imm_count;      /* imm-data (bytes)   */