cam/scsi: Support well known logical unit

This patch adds an additional state to probe well-known logical units
before probing normal logical units.

Reviewed by:		imp (mentor)
Sponsored by:		Samsung Electronics
Differential Revision:	https://reviews.freebsd.org/D53920

sys/cam/cam_ccb.h

@@ -614,6 +614,7 @@ typedef enum {
 } pi_tmflag;
 
 typedef enum {
+	PIM_WLUNS	= 0x400,/* Well known LUNs supported */
 	PIM_ATA_EXT	= 0x200,/* ATA requests can understand ata_ext requests */
 	PIM_EXTLUNS	= 0x100,/* 64bit extended LUNs supported */
 	PIM_SCANHILO	= 0x80,	/* Bus scans from high ID to low ID */

sys/cam/cam_xpt.c

@@ -4682,6 +4682,7 @@ xpt_alloc_target(struct cam_eb *bus, target_id_t target_id)
 	target->refcount = 1;
 	target->generation = 0;
 	target->luns = NULL;
+	target->wluns = NULL;
 	mtx_init(&target->luns_mtx, "CAM LUNs lock", NULL, MTX_DEF);
 	timevalclear(&target->last_reset);
 	/*

sys/cam/cam_xpt_internal.h

@@ -169,6 +169,7 @@ struct cam_et {
 	struct		timeval last_reset;
 	u_int		rpl_size;
 	struct scsi_report_luns_data *luns;
+	struct scsi_report_luns_data *wluns;
 	struct mtx	luns_mtx;	/* Protection for luns field. */
 };
 

sys/cam/scsi/scsi_all.h

@@ -3057,7 +3057,7 @@ struct scsi_report_luns_data {
 	uint8_t length[4];	/* length of LUN inventory, in bytes */
 	uint8_t reserved[4];	/* unused */
 	/*
-	 * LUN inventory- we only support the type zero form for now.
+	 * LUN inventory- we only support type zero and extended (well-known) formats.
 	 */
 	struct scsi_report_luns_lundata luns[0];
 };

sys/cam/scsi/scsi_xpt.c

@@ -130,6 +130,7 @@ typedef enum {
 	PROBE_TUR,
 	PROBE_INQUIRY,	/* this counts as DV0 for Basic Domain Validation */
 	PROBE_FULL_INQUIRY,
+	PROBE_REPORT_WLUNS,
 	PROBE_REPORT_LUNS,
 	PROBE_MODE_SENSE,
 	PROBE_SUPPORTED_VPD_LIST,
@@ -148,6 +149,7 @@ static char *probe_action_text[] = {
 	"PROBE_TUR",
 	"PROBE_INQUIRY",
 	"PROBE_FULL_INQUIRY",
+	"PROBE_REPORT_WLUNS",
 	"PROBE_REPORT_LUNS",
 	"PROBE_MODE_SENSE",
 	"PROBE_SUPPORTED_VPD_LIST",
@@ -567,7 +569,7 @@ static int       proberequestbackoff(struct cam_periph *periph,
 static void	 probedone(struct cam_periph *periph, union ccb *done_ccb);
 static void	 probe_purge_old(struct cam_path *path,
 				 struct scsi_report_luns_data *new,
-				 probe_flags flags);
+				 probe_flags flags, bool is_wlun);
 static void	 probecleanup(struct cam_periph *periph);
 static void	 scsi_find_quirk(struct cam_ed *device);
 static void	 scsi_scan_bus(struct cam_periph *periph, union ccb *ccb);
@@ -817,6 +819,23 @@ probestart(struct cam_periph *periph, union ccb *start_ccb)
 			     /*timeout*/60 * 1000);
 		break;
 	}
+	case PROBE_REPORT_WLUNS:
+	{
+		void *rp;
+
+		rp = malloc(periph->path->target->rpl_size,
+		    M_CAMXPT, M_NOWAIT | M_ZERO);
+		if (rp == NULL) {
+			xpt_print(periph->path,
+			    "Unable to alloc report wluns storage\n");
+			PROBE_SET_ACTION(softc, PROBE_REPORT_LUNS);
+			goto again;
+		}
+		scsi_report_luns(csio, 5, probedone, MSG_SIMPLE_Q_TAG,
+		    RPL_REPORT_WELLKNOWN, rp, periph->path->target->rpl_size,
+		    SSD_FULL_SIZE, 60000);
+		break;
+	}
 	case PROBE_REPORT_LUNS:
 	{
 		void *rp;
@@ -1162,6 +1181,7 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 	struct cam_path *path;
 	struct scsi_inquiry_data *inq_buf;
 	uint32_t  priority;
+	struct ccb_pathinq cpi;
 
 	CAM_DEBUG(done_ccb->ccb_h.path, CAM_DEBUG_TRACE, ("probedone\n"));
 
@@ -1169,6 +1189,7 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 	path = done_ccb->ccb_h.path;
 	priority = done_ccb->ccb_h.pinfo.priority;
 	cam_periph_assert(periph, MA_OWNED);
+	xpt_path_inq(&cpi, path);
 
 	switch (softc->action) {
 	case PROBE_TUR:
@@ -1235,8 +1256,10 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 				    SID_ANSI_REV(inq_buf) > SCSI_REV_SPC2 &&
 				    (SCSI_QUIRK(path->device)->quirks &
 				     CAM_QUIRK_NORPTLUNS) == 0) {
-					PROBE_SET_ACTION(softc,
-					    PROBE_REPORT_LUNS);
+					if (cpi.hba_misc & PIM_WLUNS)
+						PROBE_SET_ACTION(softc, PROBE_REPORT_WLUNS);
+					else
+						PROBE_SET_ACTION(softc, PROBE_REPORT_LUNS);
 					/*
 					 * Start with room for *one* lun.
 					 */
@@ -1259,6 +1282,9 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 			    SID_ANSI_REV(inq_buf) >= SCSI_REV_SPC2 &&
 			    (SCSI_QUIRK(path->device)->quirks &
 			     CAM_QUIRK_NORPTLUNS) == 0) {
+				if (cpi.hba_misc & PIM_WLUNS)
+					PROBE_SET_ACTION(softc,	PROBE_REPORT_WLUNS);
+				else
 					PROBE_SET_ACTION(softc, PROBE_REPORT_LUNS);
 				periph->path->target->rpl_size = 16;
 				xpt_release_ccb(done_ccb);
@@ -1296,11 +1322,13 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 		xpt_release_ccb(done_ccb);
 		break;
 	}
+	case PROBE_REPORT_WLUNS:
 	case PROBE_REPORT_LUNS:
 	{
 		struct ccb_scsiio *csio;
 		struct scsi_report_luns_data *lp;
 		u_int nlun, maxlun;
+		bool is_wlun = softc->action == PROBE_REPORT_WLUNS;
 
 		csio = &done_ccb->csio;
 
@@ -1377,7 +1405,7 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 			 * This function will also install the new list
 			 * in the target structure.
 			 */
-			probe_purge_old(path, lp, softc->flags);
+			probe_purge_old(path, lp, softc->flags, is_wlun);
 			lp = NULL;
 		}
 		/* The processing above should either exit via a `goto
@@ -1390,7 +1418,9 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 		if (path->device->flags & CAM_DEV_INQUIRY_DATA_VALID &&
 		    (SID_QUAL(inq_buf) == SID_QUAL_LU_CONNECTED ||
 		    SID_QUAL(inq_buf) == SID_QUAL_LU_OFFLINE)) {
-			if (INQ_DATA_TQ_ENABLED(inq_buf))
+			if (is_wlun)
+				PROBE_SET_ACTION(softc, PROBE_REPORT_LUNS);
+			else if (INQ_DATA_TQ_ENABLED(inq_buf))
 				PROBE_SET_ACTION(softc, PROBE_MODE_SENSE);
 			else
 				PROBE_SET_ACTION(softc,
@@ -1815,20 +1845,22 @@ probedone(struct cam_periph *periph, union ccb *done_ccb)
 
 static void
 probe_purge_old(struct cam_path *path, struct scsi_report_luns_data *new,
-    probe_flags flags)
+    probe_flags flags, bool is_wlun)
 {
 	struct cam_path *tp;
-	struct scsi_report_luns_data *old;
+	struct scsi_report_luns_data **luns_data, *old;
 	u_int idx1, idx2, nlun_old, nlun_new;
 	lun_id_t this_lun;
 	uint8_t *ol, *nl;
 
+	luns_data = is_wlun ? &path->target->wluns : &path->target->luns;
+
 	if (path->target == NULL) {
 		return;
 	}
 	mtx_lock(&path->target->luns_mtx);
-	old = path->target->luns;
-	path->target->luns = new;
+	old = *luns_data;
+	*luns_data = new;
 	mtx_unlock(&path->target->luns_mtx);
 	if (old == NULL)
 		return;
@@ -1908,11 +1940,16 @@ scsi_find_quirk(struct cam_ed *device)
 	device->maxtags = quirk->maxtags;
 }
 
+typedef struct {
+	int lun;
+	int wlun;
+} lun_pair;
+
 typedef struct {
 	union	ccb *request_ccb;
 	struct 	ccb_pathinq *cpi;
 	int	counter;
-	int	lunindex[0];
+	lun_pair lunindex[0];
 } scsi_scan_bus_info;
 
 static void
@@ -1995,7 +2032,8 @@ scsi_scan_bus(struct cam_periph *periph, union ccb *request_ccb)
 
 		/* Save some state for use while we probe for devices */
 		scan_info = (scsi_scan_bus_info *) malloc(sizeof(scsi_scan_bus_info) +
-		    (work_ccb->cpi.max_target * sizeof (u_int)), M_CAMXPT, M_ZERO|M_NOWAIT);
+		    (work_ccb->cpi.max_target * sizeof(lun_pair)),
+				M_CAMXPT, M_ZERO|M_NOWAIT);
 		if (scan_info == NULL) {
 			request_ccb->ccb_h.status = CAM_RESRC_UNAVAIL;
 			xpt_free_ccb(work_ccb);
@@ -2080,6 +2118,8 @@ scsi_scan_bus(struct cam_periph *periph, union ccb *request_ccb)
 		path_id_t path_id;
 		target_id_t target_id;
 		lun_id_t lun_id;
+		u_int nwluns;
+		bool need_wlun_scan = false;
 
 		oldpath = request_ccb->ccb_h.path;
 
@@ -2093,6 +2133,40 @@ scsi_scan_bus(struct cam_periph *periph, union ccb *request_ccb)
 
 		mtx = xpt_path_mtx(scan_info->request_ccb->ccb_h.path);
 		mtx_lock(mtx);
+
+		if (scan_info->cpi->hba_misc & PIM_WLUNS) {
+			/* Scan Well known logical units */
+			mtx_lock(&target->luns_mtx);
+
+			if (target->wluns) {
+				nwluns = scsi_4btoul(target->wluns->length) / 8;
+				if (scan_info->lunindex[target_id].wlun < nwluns)
+					need_wlun_scan = true;
+			}
+
+			if (need_wlun_scan) {
+				/*
+				 * WLUN uses the Extended WLUN address format, so we can handle all of
+				 * them.
+				 */
+				CAM_GET_LUN(target->wluns, scan_info->lunindex[target_id].wlun, lun_id);
+
+				mtx_unlock(&target->luns_mtx);
+				next_target = 0;
+				CAM_DEBUG(request_ccb->ccb_h.path,
+						CAM_DEBUG_PROBE,
+					("next wlun to try at index %u is %jx\n",
+					scan_info->lunindex[target_id].wlun,
+					(uintmax_t)lun_id));
+				scan_info->lunindex[target_id].wlun++;
+			} else {
+				mtx_unlock(&target->luns_mtx);
+				/* We're done with scanning all wluns. */
+			}
+		}
+
+		if (!need_wlun_scan) {
+			/* Scan logical units */
 			mtx_lock(&target->luns_mtx);
 			if (target->luns) {
 				lun_id_t first;
@@ -2104,41 +2178,41 @@ scsi_scan_bus(struct cam_periph *periph, union ccb *request_ccb)
 				* it.
 				*/
 				CAM_GET_LUN(target->luns, 0, first);
-			if (first == 0 && scan_info->lunindex[target_id] == 0) {
-				scan_info->lunindex[target_id]++;
+				if (first == 0 && scan_info->lunindex[target_id].lun == 0) {
+					scan_info->lunindex[target_id].lun++;
 				}
 
 				/*
 				* Skip any LUNs that the HBA can't deal with.
 				*/
-			while (scan_info->lunindex[target_id] < nluns) {
+				while (scan_info->lunindex[target_id].lun < nluns) {
 					if (scan_info->cpi->hba_misc & PIM_EXTLUNS) {
 						CAM_GET_LUN(target->luns,
-					    scan_info->lunindex[target_id],
+								scan_info->lunindex[target_id].lun,
 								lun_id);
 						break;
 					}
 
 					if (CAM_CAN_GET_SIMPLE_LUN(target->luns,
-				    scan_info->lunindex[target_id])) {
+							scan_info->lunindex[target_id].lun)) {
 						CAM_GET_SIMPLE_LUN(target->luns,
-					    scan_info->lunindex[target_id],
+								scan_info->lunindex[target_id].lun,
 								lun_id);
 						break;
 					}
 
-				scan_info->lunindex[target_id]++;
+					scan_info->lunindex[target_id].lun++;
 				}
 
-			if (scan_info->lunindex[target_id] < nluns) {
+				if (scan_info->lunindex[target_id].lun < nluns) {
 					mtx_unlock(&target->luns_mtx);
 					next_target = 0;
 					CAM_DEBUG(request_ccb->ccb_h.path,
 							CAM_DEBUG_PROBE,
 						("next lun to try at index %u is %jx\n",
-				   scan_info->lunindex[target_id],
+						scan_info->lunindex[target_id].lun,
 						(uintmax_t)lun_id));
-				scan_info->lunindex[target_id]++;
+					scan_info->lunindex[target_id].lun++;
 				} else {
 					mtx_unlock(&target->luns_mtx);
 					/* We're done with scanning all luns. */
@@ -2178,6 +2252,7 @@ scsi_scan_bus(struct cam_periph *periph, union ccb *request_ccb)
 						next_target = 1;
 				}
 			}
+		}
 
 		/*
 		 * Check to see if we scan any further luns.