---

yaml
---
r: 213355
b: refs/heads/master
c: 045d3fe
h: refs/heads/master
i:
  213353: 27d18d3
  213351: 19834e2
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a36c61f9025b8924f99f54d518763bee7aa84085
+refs/heads/master: 045d3fe766b01921e24e2d4178e011b3b09ad4d6

trunk/drivers/scsi/sd.c

@@ -2039,14 +2039,24 @@ static void sd_read_block_limits(struct scsi_disk *sdkp)
 		lba_count = get_unaligned_be32(&buffer[20]);
 		desc_count = get_unaligned_be32(&buffer[24]);
 
-		if (lba_count) {
-			q->limits.max_discard_sectors =
-				lba_count * sector_sz >> 9;
-
-			if (desc_count)
+		if (lba_count && desc_count) {
+			if (sdkp->tpvpd && !sdkp->tpu)
+				sdkp->unmap = 0;
+			else
 				sdkp->unmap = 1;
 		}
 
+		if (sdkp->tpvpd && !sdkp->tpu && !sdkp->tpws) {
+			sd_printk(KERN_ERR, sdkp, "Thin provisioning is " \
+				  "enabled but neither TPU, nor TPWS are " \
+				  "set. Disabling discard!\n");
+			goto out;
+		}
+
+		if (lba_count)
+			q->limits.max_discard_sectors =
+				lba_count * sector_sz >> 9;
+
 		granularity = get_unaligned_be32(&buffer[28]);
 
 		if (granularity)
@@ -2087,6 +2097,31 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp)
 	kfree(buffer);
 }
 
+/**
+ * sd_read_thin_provisioning - Query thin provisioning VPD page
+ * @disk: disk to query
+ */
+static void sd_read_thin_provisioning(struct scsi_disk *sdkp)
+{
+	unsigned char *buffer;
+	const int vpd_len = 8;
+
+	if (sdkp->thin_provisioning == 0)
+		return;
+
+	buffer = kmalloc(vpd_len, GFP_KERNEL);
+
+	if (!buffer || scsi_get_vpd_page(sdkp->device, 0xb2, buffer, vpd_len))
+		goto out;
+
+	sdkp->tpvpd = 1;
+	sdkp->tpu   = (buffer[5] >> 7) & 1;	/* UNMAP */
+	sdkp->tpws  = (buffer[5] >> 6) & 1;	/* WRITE SAME(16) with UNMAP */
+
+ out:
+	kfree(buffer);
+}
+
 static int sd_try_extended_inquiry(struct scsi_device *sdp)
 {
 	/*
@@ -2138,6 +2173,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
 		sd_read_capacity(sdkp, buffer);
 
 		if (sd_try_extended_inquiry(sdp)) {
+			sd_read_thin_provisioning(sdkp);
 			sd_read_block_limits(sdkp);
 			sd_read_block_characteristics(sdkp);
 		}

trunk/drivers/scsi/sd.h

@@ -63,6 +63,9 @@ struct scsi_disk {
 	unsigned	first_scan : 1;
 	unsigned	thin_provisioning : 1;
 	unsigned	unmap : 1;
+	unsigned	tpws : 1;
+	unsigned	tpu : 1;
+	unsigned	tpvpd : 1;
 };
 #define to_scsi_disk(obj) container_of(obj,struct scsi_disk,dev)