MFC r289146:

Make delete method set via kern.cam.da.X.delete_method persistent.

This allows to set delete method via tunable, before device capabilities
are known.  Also allow ZERO method for devices not reporting LBP, if user
explicitly requests it -- it may be useful if storage supports compression
and WRITE SAME, but does not support UNMAP.

1 files changed, 35 insertions, 37 deletions

diff --git a/sys/cam/scsi/scsi_da.c b/sys/cam/scsi/scsi_da.c
index 0fa5a11..90c917c 100644
--- a/sys/cam/scsi/scsi_da.c
+++ b/sys/cam/scsi/scsi_da.c
@@ -219,6 +219,7 @@ struct da_softc {
 	uint32_t		unmap_max_ranges;
 	uint32_t		unmap_max_lba; /* Max LBAs in UNMAP req */
 	uint64_t		ws_max_blks;
+	da_delete_methods	delete_method_pref;
 	da_delete_methods	delete_method;
 	da_delete_func_t	*delete_func;
 	struct	 disk_params params;
@@ -1805,7 +1806,7 @@ dasysctlinit(void *context, int pending)
 	 * the fly.
 	 */
 	SYSCTL_ADD_PROC(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
-		OID_AUTO, "delete_method", CTLTYPE_STRING | CTLFLAG_RW,
+		OID_AUTO, "delete_method", CTLTYPE_STRING | CTLFLAG_RWTUN,
 		softc, 0, dadeletemethodsysctl, "A",
 		"BIO_DELETE execution method");
 	SYSCTL_ADD_PROC(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree),
@@ -1916,7 +1917,6 @@ static void
 dadeletemethodset(struct da_softc *softc, da_delete_methods delete_method)
 {
 
-
 	softc->delete_method = delete_method;
 	softc->disk->d_delmaxsize = dadeletemaxsize(softc, delete_method);
 	softc->delete_func = da_delete_functions[delete_method];
@@ -1969,25 +1969,17 @@ daprobedone(struct cam_periph *periph, union ccb *ccb)
 
 		snprintf(buf, sizeof(buf), "Delete methods: <");
 		sep = 0;
-		for (i = DA_DELETE_MIN; i <= DA_DELETE_MAX; i++) {
-			if (softc->delete_available & (1 << i)) {
-				if (sep) {
-					strlcat(buf, ",", sizeof(buf));
-				} else {
-				    sep = 1;
-				}
-				strlcat(buf, da_delete_method_names[i],
-				    sizeof(buf));
-				if (i == softc->delete_method) {
-					strlcat(buf, "(*)", sizeof(buf));
-				}
-			}
-		}
-		if (sep == 0) {
-			if (softc->delete_method == DA_DELETE_NONE) 
-				strlcat(buf, "NONE(*)", sizeof(buf));
-			else
-				strlcat(buf, "DISABLED(*)", sizeof(buf));
+		for (i = 0; i <= DA_DELETE_MAX; i++) {
+			if ((softc->delete_available & (1 << i)) == 0 &&
+			    i != softc->delete_method)
+				continue;
+			if (sep)
+				strlcat(buf, ",", sizeof(buf));
+			strlcat(buf, da_delete_method_names[i],
+			    sizeof(buf));
+			if (i == softc->delete_method)
+				strlcat(buf, "(*)", sizeof(buf));
+			sep = 1;
 		}
 		strlcat(buf, ">", sizeof(buf));
 		printf("%s%d: %s\n", periph->periph_name,
@@ -2017,21 +2009,28 @@ daprobedone(struct cam_periph *periph, union ccb *ccb)
 static void
 dadeletemethodchoose(struct da_softc *softc, da_delete_methods default_method)
 {
-	int i, delete_method;
+	int i, methods;
 
-	delete_method = default_method;
+	/* If available, prefer the method requested by user. */
+	i = softc->delete_method_pref;
+	methods = softc->delete_available | (1 << DA_DELETE_DISABLE);
+	if (methods & (1 << i)) {
+		dadeletemethodset(softc, i);
+		return;
+	}
 
-	/*
-	 * Use the pre-defined order to choose the best
-	 * performing delete.
-	 */
+	/* Use the pre-defined order to choose the best performing delete. */
 	for (i = DA_DELETE_MIN; i <= DA_DELETE_MAX; i++) {
+		if (i == DA_DELETE_ZERO)
+			continue;
 		if (softc->delete_available & (1 << i)) {
 			dadeletemethodset(softc, i);
 			return;
 		}
 	}
-	dadeletemethodset(softc, delete_method);
+
+	/* Fallback to default. */
+	dadeletemethodset(softc, default_method);
 }
 
 static int
@@ -2055,13 +2054,14 @@ dadeletemethodsysctl(SYSCTL_HANDLER_ARGS)
 		return (error);
 	methods = softc->delete_available | (1 << DA_DELETE_DISABLE);
 	for (i = 0; i <= DA_DELETE_MAX; i++) {
-		if (!(methods & (1 << i)) ||
-		    strcmp(buf, da_delete_method_names[i]) != 0)
-			continue;
-		dadeletemethodset(softc, i);
-		return (0);
+		if (strcmp(buf, da_delete_method_names[i]) == 0)
+			break;
 	}
-	return (EINVAL);
+	if (i > DA_DELETE_MAX)
+		return (EINVAL);
+	softc->delete_method_pref = i;
+	dadeletemethodchoose(softc, DA_DELETE_NONE);
+	return (0);
 }
 
 static cam_status
@@ -3298,6 +3298,7 @@ dadone(struct cam_periph *periph, union ccb *done_ccb)
 
 		/* Ensure re-probe doesn't see old delete. */
 		softc->delete_available = 0;
+		dadeleteflag(softc, DA_DELETE_ZERO, 1);
 		if (lbp && (softc->quirks & DA_Q_NO_UNMAP) == 0) {
 			/*
 			 * Based on older SBC-3 spec revisions
@@ -3314,7 +3315,6 @@ dadone(struct cam_periph *periph, union ccb *done_ccb)
 			 */
 			dadeleteflag(softc, DA_DELETE_WS16, 1);
 			dadeleteflag(softc, DA_DELETE_WS10, 1);
-			dadeleteflag(softc, DA_DELETE_ZERO, 1);
 			dadeleteflag(softc, DA_DELETE_UNMAP, 1);
 
 			xpt_release_ccb(done_ccb);
@@ -3343,8 +3343,6 @@ dadone(struct cam_periph *periph, union ccb *done_ccb)
 				     (lbp->flags & SVPD_LBP_WS16));
 			dadeleteflag(softc, DA_DELETE_WS10,
 				     (lbp->flags & SVPD_LBP_WS10));
-			dadeleteflag(softc, DA_DELETE_ZERO,
-				     (lbp->flags & SVPD_LBP_WS10));
 			dadeleteflag(softc, DA_DELETE_UNMAP,
 				     (lbp->flags & SVPD_LBP_UNMAP));
 		} else {