libfc: Add runtime debugging with debug_logging module parameter

This patch adds the /sys/module/libfc/parameters/debug_logging
file to sysfs as a module parameter. It accepts an integer
bitmask for logging. Currently it supports:

   bit
LSB 0 = general libfc debugging
    1 = lport debugging
    2 = disc debugging
    3 = rport debugging
    4 = fcp debugging
    5 = EM debugging
    6 = exch/seq debugging
    7 = scsi logging (mostly error handling)

the other bits are not used at this time.

The patch converts all of the libfc source files to use
these new macros and removes the old FC_DBG macro.

Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 35 insertions, 48 deletions

diff --git a/drivers/scsi/libfc/fc_disc.c b/drivers/scsi/libfc/fc_disc.c
index 4c880656990..6fabf66972b 100644
--- a/drivers/scsi/libfc/fc_disc.c
+++ b/drivers/scsi/libfc/fc_disc.c
@@ -45,14 +45,6 @@
 
 #define	FC_DISC_DELAY		3
 
-static int fc_disc_debug;
-
-#define FC_DEBUG_DISC(fmt...)			\
-	do {					\
-		if (fc_disc_debug)		\
-			FC_DBG(fmt);		\
-	} while (0)
-
 static void fc_disc_gpn_ft_req(struct fc_disc *);
 static void fc_disc_gpn_ft_resp(struct fc_seq *, struct fc_frame *, void *);
 static int fc_disc_new_target(struct fc_disc *, struct fc_rport *,
@@ -137,8 +129,8 @@ static void fc_disc_rport_callback(struct fc_lport *lport,
 	struct fc_rport_libfc_priv *rdata = rport->dd_data;
 	struct fc_disc *disc = &lport->disc;
 
-	FC_DEBUG_DISC("Received a %d event for port (%6x)\n", event,
-		      rport->port_id);
+	FC_DISC_DBG(disc, "Received a %d event for port (%6x)\n", event,
+		    rport->port_id);
 
 	switch (event) {
 	case RPORT_EV_CREATED:
@@ -191,8 +183,7 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 
 	lport = disc->lport;
 
-	FC_DEBUG_DISC("Received an RSCN event on port (%6x)\n",
-		      fc_host_port_id(lport->host));
+	FC_DISC_DBG(disc, "Received an RSCN event\n");
 
 	/* make sure the frame contains an RSCN message */
 	rp = fc_frame_payload_get(fp, sizeof(*rp));
@@ -225,8 +216,8 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 		 */
 		switch (fmt) {
 		case ELS_ADDR_FMT_PORT:
-			FC_DEBUG_DISC("Port address format for port (%6x)\n",
-				      ntoh24(pp->rscn_fid));
+			FC_DISC_DBG(disc, "Port address format for port "
+				    "(%6x)\n", ntoh24(pp->rscn_fid));
 			dp = kzalloc(sizeof(*dp), GFP_KERNEL);
 			if (!dp) {
 				redisc = 1;
@@ -243,19 +234,19 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 		case ELS_ADDR_FMT_DOM:
 		case ELS_ADDR_FMT_FAB:
 		default:
-			FC_DEBUG_DISC("Address format is (%d)\n", fmt);
+			FC_DISC_DBG(disc, "Address format is (%d)\n", fmt);
 			redisc = 1;
 			break;
 		}
 	}
 	lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL);
 	if (redisc) {
-		FC_DEBUG_DISC("RSCN received: rediscovering\n");
+		FC_DISC_DBG(disc, "RSCN received: rediscovering\n");
 		fc_disc_restart(disc);
 	} else {
-		FC_DEBUG_DISC("RSCN received: not rediscovering. "
-			      "redisc %d state %d in_prog %d\n",
-			      redisc, lport->state, disc->pending);
+		FC_DISC_DBG(disc, "RSCN received: not rediscovering. "
+			    "redisc %d state %d in_prog %d\n",
+			    redisc, lport->state, disc->pending);
 		list_for_each_entry_safe(dp, next, &disc_ports, peers) {
 			list_del(&dp->peers);
 			rport = lport->tt.rport_lookup(lport, dp->ids.port_id);
@@ -270,7 +261,7 @@ static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp,
 	fc_frame_free(fp);
 	return;
 reject:
-	FC_DEBUG_DISC("Received a bad RSCN frame\n");
+	FC_DISC_DBG(disc, "Received a bad RSCN frame\n");
 	rjt_data.fp = NULL;
 	rjt_data.reason = ELS_RJT_LOGIC;
 	rjt_data.explan = ELS_EXPL_NONE;
@@ -302,7 +293,8 @@ static void fc_disc_recv_req(struct fc_seq *sp, struct fc_frame *fp,
 		mutex_unlock(&disc->disc_mutex);
 		break;
 	default:
-		FC_DBG("Received an unsupported request. opcode (%x)\n", op);
+		FC_DISC_DBG(disc, "Received an unsupported request, "
+			    "the opcode is (%x)\n", op);
 		break;
 	}
 }
@@ -320,12 +312,10 @@ static void fc_disc_restart(struct fc_disc *disc)
 	struct fc_rport_libfc_priv *rdata, *next;
 	struct fc_lport *lport = disc->lport;
 
-	FC_DEBUG_DISC("Restarting discovery for port (%6x)\n",
-		      fc_host_port_id(lport->host));
+	FC_DISC_DBG(disc, "Restarting discovery\n");
 
 	list_for_each_entry_safe(rdata, next, &disc->rports, peers) {
 		rport = PRIV_TO_RPORT(rdata);
-		FC_DEBUG_DISC("list_del(%6x)\n", rport->port_id);
 		list_del(&rdata->peers);
 		lport->tt.rport_logoff(rport);
 	}
@@ -485,8 +475,7 @@ static void fc_disc_done(struct fc_disc *disc)
 	struct fc_lport *lport = disc->lport;
 	enum fc_disc_event event;
 
-	FC_DEBUG_DISC("Discovery complete for port (%6x)\n",
-		      fc_host_port_id(lport->host));
+	FC_DISC_DBG(disc, "Discovery complete\n");
 
 	event = disc->event;
 	disc->event = DISC_EV_NONE;
@@ -510,10 +499,10 @@ static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp)
 {
 	struct fc_lport *lport = disc->lport;
 	unsigned long delay = 0;
-	if (fc_disc_debug)
-		FC_DBG("Error %ld, retries %d/%d\n",
-		       PTR_ERR(fp), disc->retry_count,
-		       FC_DISC_RETRY_LIMIT);
+
+	FC_DISC_DBG(disc, "Error %ld, retries %d/%d\n",
+		    PTR_ERR(fp), disc->retry_count,
+		    FC_DISC_RETRY_LIMIT);
 
 	if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) {
 		/*
@@ -649,9 +638,9 @@ static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len)
 					      &disc->rogue_rports);
 				lport->tt.rport_login(rport);
 			} else
-				FC_DBG("Failed to allocate memory for "
-				       "the newly discovered port (%6x)\n",
-				       dp.ids.port_id);
+				printk(KERN_WARNING "libfc: Failed to allocate "
+				       "memory for the newly discovered port "
+				       "(%6x)\n", dp.ids.port_id);
 		}
 
 		if (np->fp_flags & FC_NS_FID_LAST) {
@@ -671,9 +660,8 @@ static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len)
 	 */
 	if (error == 0 && len > 0 && len < sizeof(*np)) {
 		if (np != &disc->partial_buf) {
-			FC_DEBUG_DISC("Partial buffer remains "
-				      "for discovery by (%6x)\n",
-				      fc_host_port_id(lport->host));
+			FC_DISC_DBG(disc, "Partial buffer remains "
+				    "for discovery\n");
 			memcpy(&disc->partial_buf, np, len);
 		}
 		disc->buf_len = (unsigned char) len;
@@ -721,8 +709,7 @@ static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp,
 	int error;
 
 	mutex_lock(&disc->disc_mutex);
-	FC_DEBUG_DISC("Received a GPN_FT response on port (%6x)\n",
-		      fc_host_port_id(disc->lport->host));
+	FC_DISC_DBG(disc, "Received a GPN_FT response\n");
 
 	if (IS_ERR(fp)) {
 		fc_disc_error(disc, fp);
@@ -738,30 +725,30 @@ static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp,
 	    disc->seq_count == 0) {
 		cp = fc_frame_payload_get(fp, sizeof(*cp));
 		if (!cp) {
-			FC_DBG("GPN_FT response too short, len %d\n",
-			       fr_len(fp));
+			FC_DISC_DBG(disc, "GPN_FT response too short, len %d\n",
+				    fr_len(fp));
 		} else if (ntohs(cp->ct_cmd) == FC_FS_ACC) {
 
 			/* Accepted, parse the response. */
 			buf = cp + 1;
 			len -= sizeof(*cp);
 		} else if (ntohs(cp->ct_cmd) == FC_FS_RJT) {
-			FC_DBG("GPN_FT rejected reason %x exp %x "
-			       "(check zoning)\n", cp->ct_reason,
-			       cp->ct_explan);
+			FC_DISC_DBG(disc, "GPN_FT rejected reason %x exp %x "
+				    "(check zoning)\n", cp->ct_reason,
+				    cp->ct_explan);
 			disc->event = DISC_EV_FAILED;
 			fc_disc_done(disc);
 		} else {
-			FC_DBG("GPN_FT unexpected response code %x\n",
-			       ntohs(cp->ct_cmd));
+			FC_DISC_DBG(disc, "GPN_FT unexpected response code "
+				    "%x\n", ntohs(cp->ct_cmd));
 		}
 	} else if (fr_sof(fp) == FC_SOF_N3 &&
 		   seq_cnt == disc->seq_count) {
 		buf = fh + 1;
 	} else {
-		FC_DBG("GPN_FT unexpected frame - out of sequence? "
-		       "seq_cnt %x expected %x sof %x eof %x\n",
-		       seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp));
+		FC_DISC_DBG(disc, "GPN_FT unexpected frame - out of sequence? "
+			    "seq_cnt %x expected %x sof %x eof %x\n",
+			    seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp));
 	}
 	if (buf) {
 		error = fc_disc_gpn_ft_parse(disc, buf, len);