From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Date: Fri, 22 Jul 2011 13:30:15 +0000 (-0400)
Subject: xen/blk[front|back]: Use the full FLUSH | FUA instead of just FLUSH.
X-Git-Tag: next-20110816~9^2^2~3
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f7df9f0c55908ace025ba804dcce72dac6e9730a;p=karo-tx-linux.git

xen/blk[front|back]: Use the full FLUSH | FUA instead of just FLUSH.

During a FLUSH we can pass sector number that we want to
have flushed - which is what FUA requests are.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 2330a9ad5e95..8c42986a9525 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -561,7 +561,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 		break;
 	case BLKIF_OP_FLUSH_DISKCACHE:
 		blkif->st_f_req++;
-		operation = WRITE_FLUSH;
+		operation = WRITE_FLUSH_FUA;
 		break;
 	case BLKIF_OP_WRITE_BARRIER:
 	default:
@@ -572,7 +572,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 
 	/* Check that the number of segments is sane. */
 	nseg = req->nr_segments;
-	if (unlikely(nseg == 0 && operation != WRITE_FLUSH) ||
+	if (unlikely(nseg == 0 && operation != WRITE_FLUSH_FUA) ||
 	    unlikely(nseg > BLKIF_MAX_SEGMENTS_PER_REQUEST)) {
 		pr_debug(DRV_PFX "Bad number of segments in request (%d)\n",
 			 nseg);
@@ -656,7 +656,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 
 	/* This will be hit if the operation was a flush. */
 	if (!bio) {
-		BUG_ON(operation != WRITE_FLUSH);
+		BUG_ON(operation != WRITE_FLUSH_FUA);
 
 		bio = bio_alloc(GFP_KERNEL, 0);
 		if (unlikely(bio == NULL))
@@ -685,7 +685,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 
 	if (operation == READ)
 		blkif->st_rd_sect += preq.nr_sects;
-	else if (operation == WRITE || operation == WRITE_FLUSH)
+	else if (operation == WRITE || operation == WRITE_FLUSH_FUA)
 		blkif->st_wr_sect += preq.nr_sects;
 
 	return 0;
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 9ea8c2576c70..67d656b1adc6 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1148,7 +1148,7 @@ static void blkfront_connect(struct blkfront_info *info)
 		return;
 	}
 
-	info->feature_flush = 0;
+	info->feature_flush = REQ_FLUSH | REQ_FUA;
 	info->flush_op = 0;
 
 	err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
@@ -1163,7 +1163,6 @@ static void blkfront_connect(struct blkfront_info *info)
 	 * If there are barriers, then we use flush.
 	 */
 	if (!err && barrier) {
-		info->feature_flush = REQ_FLUSH | REQ_FUA;
 		info->flush_op = BLKIF_OP_WRITE_BARRIER;
 	}
 	/*
@@ -1175,10 +1174,12 @@ static void blkfront_connect(struct blkfront_info *info)
 			    NULL);
 
 	if (!err && flush) {
-		info->feature_flush = REQ_FLUSH;
 		info->flush_op = BLKIF_OP_FLUSH_DISKCACHE;
 	}
-		
+
+	if (!flush && !barrier)
+		info->feature_flush = 0;
+
 	err = xlvbd_alloc_gendisk(sectors, info, binfo, sector_size);
 	if (err) {
 		xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s",