From 196619d9ccd238a9e37a438c8b9bcc62c96e879c Mon Sep 17 00:00:00 2001
From: Alexander Motin <mav@FreeBSD.org>
Date: Sat, 27 Jul 2013 22:19:34 +0000
Subject: [PATCH] Detect unsupported PREVENT ALLOW MEDIUM REMOVAL and
 SYNCHRONIZE CACHE(10) to not spam devices with useless commands and logs with
 errors.

---
 sys/cam/scsi/scsi_da.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/sys/cam/scsi/scsi_da.c b/sys/cam/scsi/scsi_da.c
index a2b802cc669e..715f4c6b025c 100644
--- a/sys/cam/scsi/scsi_da.c
+++ b/sys/cam/scsi/scsi_da.c
@@ -535,6 +535,7 @@ static struct da_quirk_entry da_quirk_table[] =
 		{T_DIRECT, SIP_MEDIA_REMOVABLE, "TOSHIBA", "TransMemory",
 		"*"}, /*quirks*/ DA_Q_NO_SYNC_CACHE
 	},
+#if 0
 	{
 		/*
 		 * PNY USB Flash keys
@@ -543,6 +544,7 @@ static struct da_quirk_entry da_quirk_table[] =
 		{T_DIRECT, SIP_MEDIA_REMOVABLE, "*" , "USB DISK*",
 		"*"}, /*quirks*/ DA_Q_NO_SYNC_CACHE
 	},
+#endif
 	{
 		/*
 		 * Genesys 6-in-1 Card Reader
@@ -2786,6 +2788,28 @@ cmd6workaround(union ccb *ccb)
 		return (0);
 	}
 
+	/* Detect unsupported PREVENT ALLOW MEDIUM REMOVAL. */
+	if ((ccb->ccb_h.flags & CAM_CDB_POINTER) == 0 &&
+	    (*cdb == PREVENT_ALLOW) &&
+	    (softc->quirks & DA_Q_NO_PREVENT) == 0) {
+		if (bootverbose)
+			xpt_print(ccb->ccb_h.path,
+			    "PREVENT ALLOW MEDIUM REMOVAL not supported.\n");
+		softc->quirks |= DA_Q_NO_PREVENT;
+		return (0);
+	}
+
+	/* Detect unsupported SYNCHRONIZE CACHE(10). */
+	if ((ccb->ccb_h.flags & CAM_CDB_POINTER) == 0 &&
+	    (*cdb == SYNCHRONIZE_CACHE) &&
+	    (softc->quirks & DA_Q_NO_SYNC_CACHE) == 0) {
+		if (bootverbose)
+			xpt_print(ccb->ccb_h.path,
+			    "SYNCHRONIZE CACHE(10) not supported.\n");
+		softc->quirks |= DA_Q_NO_SYNC_CACHE;
+		return (0);
+	}
+
 	/* Translation only possible if CDB is an array and cmd is R/W6 */
 	if ((ccb->ccb_h.flags & CAM_CDB_POINTER) != 0 ||
 	    (*cdb != READ_6 && *cdb != WRITE_6))