[PATCH 13/17] snic: Use scsi_host_busy_iter() to traverse commands

[Hannes Reinecke <hare@suse.de>]

Use scsi_host_busy_iter() to traverse commands instead of hand-crafted
routines walking the command list.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
 drivers/scsi/snic/snic_scsi.c | 177 ++++++++++++++++------------------
 1 file changed, 84 insertions(+), 93 deletions(-)

diff --git a/drivers/scsi/snic/snic_scsi.c b/drivers/scsi/snic/snic_scsi.c
index 06615619b84c..48261a37d4a6 100644
--- a/drivers/scsi/snic/snic_scsi.c
+++ b/drivers/scsi/snic/snic_scsi.c
@@ -63,7 +63,7 @@ static const char * const snic_io_status_str[] = {
 	[SNIC_STAT_FATAL_ERROR]	= "SNIC_STAT_FATAL_ERROR",
 };
 
-static void snic_scsi_cleanup(struct snic *, int);
+static void snic_scsi_cleanup(struct snic *);
 
 const char *
 snic_state_to_str(unsigned int state)
@@ -958,7 +958,7 @@ snic_hba_reset_scsi_cleanup(struct snic *snic)
 	long act_ios = 0, act_fwreqs = 0;
 
 	SNIC_SCSI_DBG(snic->shost, "HBA Reset scsi cleanup.\n");
-	snic_scsi_cleanup(snic, snic->max_tag_id);
+	snic_scsi_cleanup(snic);
 
 	/* Update stats on pending IOs */
 	act_ios = atomic64_read(&st->io.active);
@@ -2357,53 +2357,36 @@ snic_cmpl_pending_tmreq(struct snic *snic, struct scsi_cmnd *sc)
 		complete(rqi->abts_done);
 }
 
-/*
- * snic_scsi_cleanup: Walks through tag map and releases the reqs
- */
-static void
-snic_scsi_cleanup(struct snic *snic, int ex_tag)
+static bool
+snic_scsi_cleanup_iter(struct scsi_cmnd *sc, void *data, bool reserved)
 {
+	struct snic *snic = data;
 	struct snic_req_info *rqi = NULL;
-	struct scsi_cmnd *sc = NULL;
 	spinlock_t *io_lock = NULL;
 	unsigned long flags;
-	int tag;
+	int tag = scsi_cmd_to_rq(sc)->tag;
 	u64 st_time = 0;
 
 	SNIC_SCSI_DBG(snic->shost, "sc_clean: scsi cleanup.\n");
 
-	for (tag = 0; tag < snic->max_tag_id; tag++) {
-		/* Skip ex_tag */
-		if (tag == ex_tag)
-			continue;
-
-		io_lock = snic_io_lock_tag(snic, tag);
-		spin_lock_irqsave(io_lock, flags);
-		sc = scsi_host_find_tag(snic->shost, tag);
-		if (!sc) {
-			spin_unlock_irqrestore(io_lock, flags);
-
-			continue;
-		}
-
-		if (unlikely(snic_tmreq_pending(sc))) {
-			/*
-			 * When FW Completes reset w/o sending completions
-			 * for outstanding ios.
-			 */
-			snic_cmpl_pending_tmreq(snic, sc);
-			spin_unlock_irqrestore(io_lock, flags);
-
-			continue;
-		}
+	io_lock = snic_io_lock_tag(snic, tag);
+	spin_lock_irqsave(io_lock, flags);
 
-		rqi = (struct snic_req_info *) CMD_SP(sc);
-		if (!rqi) {
-			spin_unlock_irqrestore(io_lock, flags);
+	if (unlikely(snic_tmreq_pending(sc))) {
+		/*
+		 * When FW Completes reset w/o sending completions
+		 * for outstanding ios.
+		 */
+		snic_cmpl_pending_tmreq(snic, sc);
+		spin_unlock_irqrestore(io_lock, flags);
 
-			goto cleanup;
-		}
+		return true;
+	}
 
+	rqi = (struct snic_req_info *) CMD_SP(sc);
+	if (!rqi)
+		spin_unlock_irqrestore(io_lock, flags);
+	else {
 		SNIC_SCSI_DBG(snic->shost,
 			      "sc_clean: sc %p, rqi %p, tag %d flags 0x%llx\n",
 			      sc, rqi, tag, CMD_FLAGS(sc));
@@ -2418,24 +2401,34 @@ snic_scsi_cleanup(struct snic *snic, int ex_tag)
 			       rqi, CMD_FLAGS(sc));
 
 		snic_release_req_buf(snic, rqi, sc);
+	}
+	sc->result = DID_TRANSPORT_DISRUPTED << 16;
+	SNIC_HOST_INFO(snic->shost,
+		       "sc_clean: DID_TRANSPORT_DISRUPTED for sc %p, Tag %d flags 0x%llx rqi %p duration %u msecs\n",
+		       sc, tag, CMD_FLAGS(sc), rqi,
+		       jiffies_to_msecs(jiffies - st_time));
 
-cleanup:
-		sc->result = DID_TRANSPORT_DISRUPTED << 16;
-		SNIC_HOST_INFO(snic->shost,
-			       "sc_clean: DID_TRANSPORT_DISRUPTED for sc %p, Tag %d flags 0x%llx rqi %p duration %u msecs\n",
-			       sc, scsi_cmd_to_rq(sc)->tag, CMD_FLAGS(sc), rqi,
-			       jiffies_to_msecs(jiffies - st_time));
+	/* Update IO stats */
+	snic_stats_update_io_cmpl(&snic->s_stats);
 
-		/* Update IO stats */
-		snic_stats_update_io_cmpl(&snic->s_stats);
+	SNIC_TRC(snic->shost->host_no, tag, (ulong) sc,
+		 jiffies_to_msecs(jiffies - st_time), 0,
+		 SNIC_TRC_CMD(sc),
+		 SNIC_TRC_CMD_STATE_FLAGS(sc));
 
-		SNIC_TRC(snic->shost->host_no, tag, (ulong) sc,
-			 jiffies_to_msecs(jiffies - st_time), 0,
-			 SNIC_TRC_CMD(sc),
-			 SNIC_TRC_CMD_STATE_FLAGS(sc));
+	scsi_done(sc);
+	return true;
+}
 
-		scsi_done(sc);
-	}
+/*
+ * snic_scsi_cleanup: Walks through tag map and releases the reqs
+ */
+static void
+snic_scsi_cleanup(struct snic *snic)
+{
+	SNIC_SCSI_DBG(snic->shost, "sc_clean: scsi cleanup\n");
+
+	scsi_host_busy_iter(snic->shost, snic_scsi_cleanup_iter, snic);
 } /* end of snic_scsi_cleanup */
 
 void
@@ -2443,7 +2436,7 @@ snic_shutdown_scsi_cleanup(struct snic *snic)
 {
 	SNIC_HOST_INFO(snic->shost, "Shutdown time SCSI Cleanup.\n");
 
-	snic_scsi_cleanup(snic, SCSI_NO_TAG);
+	snic_scsi_cleanup(snic);
 } /* end of snic_shutdown_scsi_cleanup */
 
 /*
@@ -2457,7 +2450,7 @@ snic_internal_abort_io(struct snic *snic, struct scsi_cmnd *sc, int tmf)
 	spinlock_t *io_lock = NULL;
 	unsigned long flags;
 	u32 sv_state = 0;
-	int ret = 0;
+	int ret = FAILED;
 
 	io_lock = snic_io_lock_hash(snic, sc);
 	spin_lock_irqsave(io_lock, flags);
@@ -2532,6 +2525,35 @@ snic_internal_abort_io(struct snic *snic, struct scsi_cmnd *sc, int tmf)
 	return ret;
 } /* end of snic_internal_abort_io */
 
+struct snic_tgt_scsi_abort_io_data {
+	struct snic *snic;
+	struct snic_tgt *tgt;
+	int tmf;
+	int abt_cnt;
+};
+
+static bool snic_tgt_scsi_abort_io_iter(struct scsi_cmnd *sc, void *data,
+					bool reserved)
+{
+	struct snic_tgt_scsi_abort_io_data *iter_data = data;
+	struct snic *snic = iter_data->snic;
+	struct snic_tgt *sc_tgt;
+	int ret;
+
+	sc_tgt = starget_to_tgt(scsi_target(sc->device));
+	if (sc_tgt != iter_data->tgt)
+		return true;
+
+	ret = snic_internal_abort_io(snic, sc, iter_data->tmf);
+	if (ret == SUCCESS)
+		iter_data->abt_cnt++;
+	else
+		SNIC_HOST_ERR(snic->shost,
+			      "tgt_abt_io: Tag %x, Failed w err = %d\n",
+			      scsi_cmd_to_rq(sc)->tag, ret);
+	return true;
+}
+
 /*
  * snic_tgt_scsi_abort_io : called by snic_tgt_del
  */
@@ -2539,11 +2561,9 @@ int
 snic_tgt_scsi_abort_io(struct snic_tgt *tgt)
 {
 	struct snic *snic = NULL;
-	struct scsi_cmnd *sc = NULL;
-	struct snic_tgt *sc_tgt = NULL;
-	spinlock_t *io_lock = NULL;
-	unsigned long flags;
-	int ret = 0, tag, abt_cnt = 0, tmf = 0;
+	struct snic_tgt_scsi_abort_io_data data = {
+		.abt_cnt = 0,
+	};
 
 	if (!tgt)
 		return -1;
@@ -2551,44 +2571,15 @@ snic_tgt_scsi_abort_io(struct snic_tgt *tgt)
 	snic = shost_priv(snic_tgt_to_shost(tgt));
 	SNIC_SCSI_DBG(snic->shost, "tgt_abt_io: Cleaning Pending IOs.\n");
 
+	data.snic = snic;
 	if (tgt->tdata.typ == SNIC_TGT_DAS)
-		tmf = SNIC_ITMF_ABTS_TASK;
+		data.tmf = SNIC_ITMF_ABTS_TASK;
 	else
-		tmf = SNIC_ITMF_ABTS_TASK_TERM;
-
-	for (tag = 0; tag < snic->max_tag_id; tag++) {
-		io_lock = snic_io_lock_tag(snic, tag);
-
-		spin_lock_irqsave(io_lock, flags);
-		sc = scsi_host_find_tag(snic->shost, tag);
-		if (!sc) {
-			spin_unlock_irqrestore(io_lock, flags);
-
-			continue;
-		}
+		data.tmf = SNIC_ITMF_ABTS_TASK_TERM;
 
-		sc_tgt = starget_to_tgt(scsi_target(sc->device));
-		if (sc_tgt != tgt) {
-			spin_unlock_irqrestore(io_lock, flags);
-
-			continue;
-		}
-		spin_unlock_irqrestore(io_lock, flags);
-
-		ret = snic_internal_abort_io(snic, sc, tmf);
-		if (ret < 0) {
-			SNIC_HOST_ERR(snic->shost,
-				      "tgt_abt_io: Tag %x, Failed w err = %d\n",
-				      tag, ret);
-
-			continue;
-		}
-
-		if (ret == SUCCESS)
-			abt_cnt++;
-	}
+	scsi_host_busy_iter(snic->shost, snic_tgt_scsi_abort_io_iter, &data);
 
-	SNIC_SCSI_DBG(snic->shost, "tgt_abt_io: abt_cnt = %d\n", abt_cnt);
+	SNIC_SCSI_DBG(snic->shost, "tgt_abt_io: abt_cnt = %d\n", data.abt_cnt);
 
 	return 0;
 } /* end of snic_tgt_scsi_abort_io */
-- 
2.35.3