[PATCHv4 08/12] mpt3sas: always use first reserved smid for ioctl passthrough

[Hannes Reinecke]

ioctl passthrough commands require a SCSIIO smid, but cannot
easily integrate with the block layer. But the driver already
has reserved some SCSIIO smids and we're only ever allowing
one ioctl command at a time we can use the first reserved smid
for ioctl commands.

Signed-off-by: Hannes Reinecke <h...@suse.com>
---
 drivers/scsi/mpt3sas/mpt3sas_base.c | 19 +++++++++++++------
 drivers/scsi/mpt3sas/mpt3sas_ctl.c  | 10 ++--------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c 
b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 3f9148c..e6aafa5 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -882,14 +882,18 @@ struct scsiio_tracker *
 _base_get_cb_idx(struct MPT3SAS_ADAPTER *ioc, u16 smid)
 {
        int i;
+       u16 ctl_smid = ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT + 1;
        u8 cb_idx = 0xFF;
 
        if (smid < ioc->hi_priority_smid) {
                struct scsiio_tracker *st;
 
-               st = mpt3sas_get_st_from_smid(ioc, smid);
-               if (st)
-                       cb_idx = st->cb_idx;
+               if (smid < ctl_smid) {
+                       st = mpt3sas_get_st_from_smid(ioc, smid);
+                       if (st)
+                               cb_idx = st->cb_idx;
+               } else if (smid == ctl_smid)
+                       cb_idx = ioc->ctl_cb_idx;
        } else if (smid < ioc->internal_smid) {
                i = smid - ioc->hi_priority_smid;
                cb_idx = ioc->hpr_lookup[i].cb_idx;
@@ -2432,7 +2436,9 @@ struct scsiio_tracker *
                ioc->scsi_lookup[i].cb_idx = 0xFF;
                ioc->scsi_lookup[i].scmd = NULL;
                ioc->scsi_lookup[i].direct_io = 0;
-               list_add(&ioc->scsi_lookup[i].tracker_list, &ioc->free_list);
+               if (i < ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT)
+                       list_add(&ioc->scsi_lookup[i].tracker_list,
+                                &ioc->free_list);
                spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
 
                _base_recovery_check(ioc);
@@ -5174,8 +5180,9 @@ struct scsiio_tracker *
                ioc->scsi_lookup[i].smid = smid;
                ioc->scsi_lookup[i].scmd = NULL;
                ioc->scsi_lookup[i].direct_io = 0;
-               list_add_tail(&ioc->scsi_lookup[i].tracker_list,
-                   &ioc->free_list);
+               if (i < ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT)
+                       list_add_tail(&ioc->scsi_lookup[i].tracker_list,
+                                     &ioc->free_list);
        }
 
        /* hi-priority queue */
diff --git a/drivers/scsi/mpt3sas/mpt3sas_ctl.c 
b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
index 02fe1c4..4476bba 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_ctl.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_ctl.c
@@ -719,14 +719,8 @@ enum block_state {
                        goto out;
                }
        } else {
-
-               smid = mpt3sas_base_get_smid_scsiio(ioc, ioc->ctl_cb_idx, NULL);
-               if (!smid) {
-                       pr_err(MPT3SAS_FMT "%s: failed obtaining a smid\n",
-                           ioc->name, __func__);
-                       ret = -EAGAIN;
-                       goto out;
-               }
+               /* Use first reserved smid for passthrough ioctls */
+               smid = ioc->scsiio_depth - INTERNAL_SCSIIO_CMDS_COUNT + 1;
        }
 
        ret = 0;
-- 
1.8.5.6