[PATCH RFC v2 05/24] csiostor: use reserved command for LUN reset

John Garry
2020-03-10T16:30:50Z

From: Hannes Reinecke <hare@suse.de>

When issuing a LUN reset we should be using a reserved command
to avoid overwriting the original command.

Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/csiostor/csio_init.c | 3 +-
drivers/scsi/csiostor/csio_scsi.c | 49 +++++++++++++++++++------------
2 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/drivers/scsi/csiostor/csio_init.c b/drivers/scsi/csiostor/csio_init.c
index 8dea7d53788a..3848289485c9 100644
--- a/drivers/scsi/csiostor/csio_init.c
+++ b/drivers/scsi/csiostor/csio_init.c
@@ -621,7 +621,8 @@ csio_shost_init(struct csio_hw *hw, struct device *dev,
/* Link common lnode to this lnode */
ln->dev_num = (shost->host_no << 16);

- shost->can_queue = CSIO_MAX_QUEUE;
+ shost->can_queue = CSIO_MAX_QUEUE - 1;
+ shost->nr_reserved_cmds = 1;
shost->this_id = -1;
shost->unique_id = shost->host_no;
shost->max_cmd_len = 16; /* Max CDB length supported */
diff --git a/drivers/scsi/csiostor/csio_scsi.c b/drivers/scsi/csiostor/csio_scsi.c
index 00cf33573136..9eacdb3d4f07 100644
--- a/drivers/scsi/csiostor/csio_scsi.c
+++ b/drivers/scsi/csiostor/csio_scsi.c
@@ -2057,10 +2057,13 @@ csio_tm_cbfn(struct csio_hw *hw, struct csio_ioreq *req)
static int
csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
{
- struct csio_lnode *ln = shost_priv(cmnd->device->host);
+ struct scsi_cmnd *reset_cmnd;
+ struct scsi_device *sdev = cmnd->device;
+ struct Scsi_Host *shost = sdev->host;
+ struct csio_lnode *ln = shost_priv(sdev->host);
struct csio_hw *hw = csio_lnode_to_hw(ln);
struct csio_scsim *scsim = csio_hw_to_scsim(hw);
- struct csio_rnode *rn = (struct csio_rnode *)(cmnd->device->hostdata);
+ struct csio_rnode *rn = (struct csio_rnode *)(sdev->hostdata);
struct csio_ioreq *ioreq = NULL;
struct csio_scsi_qset *sqset;
unsigned long flags;
@@ -2073,13 +2076,13 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
goto fail;

csio_dbg(hw, "Request to reset LUN:%llu (ssni:0x%x tgtid:%d)\n",
- cmnd->device->lun, rn->flowid, rn->scsi_id);
+ sdev->lun, rn->flowid, rn->scsi_id);

if (!csio_is_lnode_ready(ln)) {
csio_err(hw,
"LUN reset cannot be issued on non-ready"
" local node vnpi:0x%x (LUN:%llu)\n",
- ln->vnp_flowid, cmnd->device->lun);
+ ln->vnp_flowid, sdev->lun);
goto fail;
}

@@ -2099,17 +2102,22 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
csio_err(hw,
"LUN reset cannot be issued on non-ready"
" remote node ssni:0x%x (LUN:%llu)\n",
- rn->flowid, cmnd->device->lun);
+ rn->flowid, sdev->lun);
goto fail;
}

+ reset_cmnd = scsi_get_reserved_cmd(shost);
+ if (!reset_cmnd) {
+ csio_err(hw, "No free TMF request\n");
+ goto fail;
+ }
/* Get a free ioreq structure - SM is already set to uninit */
ioreq = csio_get_scsi_ioreq_lock(hw, scsim);

if (!ioreq) {
csio_err(hw, "Out of IO request elements. Active # :%d\n",
scsim->stats.n_active);
- goto fail;
+ goto fail_ret_cmnd;
}

sqset = &hw->sqset[ln->portid][smp_processor_id()];
@@ -2119,11 +2127,11 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
ioreq->iq_idx = sqset->iq_idx;
ioreq->eq_idx = sqset->eq_idx;

- csio_scsi_cmnd(ioreq) = cmnd;
- cmnd->host_scribble = (unsigned char *)ioreq;
- cmnd->SCp.Status = 0;
+ csio_scsi_cmnd(ioreq) = reset_cmnd;
+ reset_cmnd->host_scribble = (unsigned char *)ioreq;
+ reset_cmnd->SCp.Status = 0;

- cmnd->SCp.Message = FCP_TMF_LUN_RESET;
+ reset_cmnd->SCp.Message = FCP_TMF_LUN_RESET;
ioreq->tmo = CSIO_SCSI_LUNRST_TMO_MS / 1000;

/*
@@ -2140,7 +2148,7 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
sld.level = CSIO_LEV_LUN;
sld.lnode = ioreq->lnode;
sld.rnode = ioreq->rnode;
- sld.oslun = cmnd->device->lun;
+ sld.oslun = sdev->lun;

spin_lock_irqsave(&hw->lock, flags);
/* Kick off TM SM on the ioreq */
@@ -2156,14 +2164,14 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
csio_dbg(hw, "Waiting max %d secs for LUN reset completion\n",
count * (CSIO_SCSI_TM_POLL_MS / 1000));
/* Wait for completion */
- while ((((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == cmnd)
+ while ((((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == reset_cmnd)
&& count--)
msleep(CSIO_SCSI_TM_POLL_MS);

/* LUN reset timed-out */
- if (((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == cmnd) {
+ if (((struct scsi_cmnd *)csio_scsi_cmnd(ioreq)) == reset_cmnd) {
csio_err(hw, "LUN reset (%d:%llu) timed out\n",
- cmnd->device->id, cmnd->device->lun);
+ sdev->id, sdev->lun);

spin_lock_irq(&hw->lock);
csio_scsi_drvcleanup(ioreq);
@@ -2174,11 +2182,12 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
}

/* LUN reset returned, check cached status */
- if (cmnd->SCp.Status != FW_SUCCESS) {
+ if (reset_cmnd->SCp.Status != FW_SUCCESS) {
csio_err(hw, "LUN reset failed (%d:%llu), status: %d\n",
- cmnd->device->id, cmnd->device->lun, cmnd->SCp.Status);
- goto fail;
+ sdev->id, sdev->lun, reset_cmnd->SCp.Status);
+ goto fail_ret_cmnd;
}
+ scsi_put_reserved_cmd(reset_cmnd);

/* LUN reset succeeded, Start aborting affected I/Os */
/*
@@ -2196,7 +2205,7 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
if (retval != 0) {
csio_err(hw,
"Attempt to abort I/Os during LUN reset of %llu"
- " returned %d\n", cmnd->device->lun, retval);
+ " returned %d\n", sdev->lun, retval);
/* Return I/Os back to active_q */
spin_lock_irq(&hw->lock);
list_splice_tail_init(&local_q, &scsim->active_q);
@@ -2207,12 +2216,14 @@ csio_eh_lun_reset_handler(struct scsi_cmnd *cmnd)
CSIO_INC_STATS(rn, n_lun_rst);

csio_info(hw, "LUN reset occurred (%d:%llu)\n",
- cmnd->device->id, cmnd->device->lun);
+ sdev->id, sdev->lun);

return SUCCESS;

fail_ret_ioreq:
csio_put_scsi_ioreq_lock(hw, scsim, ioreq);
+fail_ret_cmnd:
+ scsi_put_reserved_cmd(reset_cmnd);
fail:
CSIO_INC_STATS(rn, n_lun_rst_fail);
return FAILED;
--
2.17.1