3 files changed, 38 insertions, 54 deletions

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 14e452896d04..a5cf7f1e871c 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -442,7 +442,7 @@ static void free_req(struct xen_blkif_ring *ring, struct pending_req *req)
  * Routines for managing virtual block devices (vbds).
  */
 static int xen_vbd_translate(struct phys_req *req, struct xen_blkif *blkif,
-			     int operation)
+			     enum req_op operation)
 {
 	struct xen_vbd *vbd = &blkif->vbd;
 	int rc = -EACCES;
@@ -931,7 +931,7 @@ static int xen_blkbk_parse_indirect(struct blkif_request *req,
 	if (rc)
 		goto unmap;
 
-	for (n = 0, i = 0; n < nseg; n++) {
+	for (n = 0; n < nseg; n++) {
 		uint8_t first_sect, last_sect;
 
 		if ((n % SEGS_PER_INDIRECT_FRAME) == 0) {
@@ -970,7 +970,6 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	int status = BLKIF_RSP_OKAY;
 	struct xen_blkif *blkif = ring->blkif;
 	struct block_device *bdev = blkif->vbd.bdev;
-	unsigned long secure;
 	struct phys_req preq;
 
 	xen_blkif_get(blkif);
@@ -987,13 +986,15 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	}
 	ring->st_ds_req++;
 
-	secure = (blkif->vbd.discard_secure &&
-		 (req->u.discard.flag & BLKIF_DISCARD_SECURE)) ?
-		 BLKDEV_DISCARD_SECURE : 0;
+	if (blkif->vbd.discard_secure &&
+	    (req->u.discard.flag & BLKIF_DISCARD_SECURE))
+		err = blkdev_issue_secure_erase(bdev,
+				req->u.discard.sector_number,
+				req->u.discard.nr_sectors, GFP_KERNEL);
+	else
+		err = blkdev_issue_discard(bdev, req->u.discard.sector_number,
+				req->u.discard.nr_sectors, GFP_KERNEL);
 
-	err = blkdev_issue_discard(bdev, req->u.discard.sector_number,
-				   req->u.discard.nr_sectors,
-				   GFP_KERNEL, secure);
 fail_response:
 	if (err == -EOPNOTSUPP) {
 		pr_debug("discard op failed, not supported\n");
@@ -1192,8 +1193,8 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	struct bio *bio = NULL;
 	struct bio **biolist = pending_req->biolist;
 	int i, nbio = 0;
-	int operation;
-	int operation_flags = 0;
+	enum req_op operation;
+	blk_opf_t operation_flags = 0;
 	struct blk_plug plug;
 	bool drain = false;
 	struct grant_page **pages = pending_req->segments;
@@ -1326,16 +1327,13 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 				     pages[i]->page,
 				     seg[i].nsec << 9,
 				     seg[i].offset) == 0)) {
-			bio = bio_alloc(GFP_KERNEL, bio_max_segs(nseg - i));
-			if (unlikely(bio == NULL))
-				goto fail_put_bio;
-
+			bio = bio_alloc(preq.bdev, bio_max_segs(nseg - i),
+					operation | operation_flags,
+					GFP_KERNEL);
 			biolist[nbio++] = bio;
-			bio_set_dev(bio, preq.bdev);
 			bio->bi_private = pending_req;
 			bio->bi_end_io  = end_block_io_op;
 			bio->bi_iter.bi_sector  = preq.sector_number;
-			bio_set_op_attrs(bio, operation, operation_flags);
 		}
 
 		preq.sector_number += seg[i].nsec;
@@ -1345,15 +1343,11 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	if (!bio) {
 		BUG_ON(operation_flags != REQ_PREFLUSH);
 
-		bio = bio_alloc(GFP_KERNEL, 0);
-		if (unlikely(bio == NULL))
-			goto fail_put_bio;
-
+		bio = bio_alloc(preq.bdev, 0, operation | operation_flags,
+				GFP_KERNEL);
 		biolist[nbio++] = bio;
-		bio_set_dev(bio, preq.bdev);
 		bio->bi_private = pending_req;
 		bio->bi_end_io  = end_block_io_op;
-		bio_set_op_attrs(bio, operation, operation_flags);
 	}
 
 	atomic_set(&pending_req->pendcnt, nbio);
@@ -1381,14 +1375,6 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 	free_req(ring, pending_req);
 	msleep(1); /* back off a bit */
 	return -EIO;
-
- fail_put_bio:
-	for (i = 0; i < nbio; i++)
-		bio_put(biolist[i]);
-	atomic_set(&pending_req->pendcnt, 1);
-	__end_block_io_op(pending_req, BLK_STS_RESOURCE);
-	msleep(1); /* back off a bit */
-	return -EIO;
 }
 
 
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index bda5c815e441..a28473470e66 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -226,6 +226,9 @@ struct xen_vbd {
 	sector_t		size;
 	unsigned int		flush_support:1;
 	unsigned int		discard_secure:1;
+	/* Connect-time cached feature_persistent parameter value */
+	unsigned int		feature_gnt_persistent_parm:1;
+	/* Persistent grants feature negotiation result */
 	unsigned int		feature_gnt_persistent:1;
 	unsigned int		overflow_max_grants:1;
 };
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 914587aabca0..c0227dfa4688 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -10,6 +10,7 @@
 
 #include <linux/module.h>
 #include <linux/kthread.h>
+#include <linux/pagemap.h>
 #include <xen/events.h>
 #include <xen/grant_table.h>
 #include "common.h"
@@ -156,6 +157,11 @@ static int xen_blkif_alloc_rings(struct xen_blkif *blkif)
 	return 0;
 }
 
+/* Enable the persistent grants feature. */
+static bool feature_persistent = true;
+module_param(feature_persistent, bool, 0644);
+MODULE_PARM_DESC(feature_persistent, "Enables the persistent grants feature");
+
 static struct xen_blkif *xen_blkif_alloc(domid_t domid)
 {
 	struct xen_blkif *blkif;
@@ -471,19 +477,12 @@ static void xen_vbd_free(struct xen_vbd *vbd)
 	vbd->bdev = NULL;
 }
 
-/* Enable the persistent grants feature. */
-static bool feature_persistent = true;
-module_param(feature_persistent, bool, 0644);
-MODULE_PARM_DESC(feature_persistent,
-		"Enables the persistent grants feature");
-
 static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 			  unsigned major, unsigned minor, int readonly,
 			  int cdrom)
 {
 	struct xen_vbd *vbd;
 	struct block_device *bdev;
-	struct request_queue *q;
 
 	vbd = &blkif->vbd;
 	vbd->handle   = handle;
@@ -510,20 +509,16 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 	}
 	vbd->size = vbd_sz(vbd);
 
-	if (vbd->bdev->bd_disk->flags & GENHD_FL_CD || cdrom)
+	if (cdrom || disk_to_cdi(vbd->bdev->bd_disk))
 		vbd->type |= VDISK_CDROM;
 	if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
 		vbd->type |= VDISK_REMOVABLE;
 
-	q = bdev_get_queue(bdev);
-	if (q && test_bit(QUEUE_FLAG_WC, &q->queue_flags))
+	if (bdev_write_cache(bdev))
 		vbd->flush_support = true;
-
-	if (q && blk_queue_secure_erase(q))
+	if (bdev_max_secure_erase_sectors(bdev))
 		vbd->discard_secure = true;
 
-	vbd->feature_gnt_persistent = feature_persistent;
-
 	pr_debug("Successful creation of handle=%04x (dom=%u)\n",
 		handle, blkif->domid);
 	return 0;
@@ -577,22 +572,21 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info
 	int err;
 	int state = 0;
 	struct block_device *bdev = be->blkif->vbd.bdev;
-	struct request_queue *q = bdev_get_queue(bdev);
 
 	if (!xenbus_read_unsigned(dev->nodename, "discard-enable", 1))
 		return;
 
-	if (blk_queue_discard(q)) {
+	if (bdev_max_discard_sectors(bdev)) {
 		err = xenbus_printf(xbt, dev->nodename,
 			"discard-granularity", "%u",
-			q->limits.discard_granularity);
+			bdev_discard_granularity(bdev));
 		if (err) {
 			dev_warn(&dev->dev, "writing discard-granularity (%d)", err);
 			return;
 		}
 		err = xenbus_printf(xbt, dev->nodename,
 			"discard-alignment", "%u",
-			q->limits.discard_alignment);
+			bdev_discard_alignment(bdev));
 		if (err) {
 			dev_warn(&dev->dev, "writing discard-alignment (%d)", err);
 			return;
@@ -913,7 +907,7 @@ again:
 	xen_blkbk_barrier(xbt, be, be->blkif->vbd.flush_support);
 
 	err = xenbus_printf(xbt, dev->nodename, "feature-persistent", "%u",
-			be->blkif->vbd.feature_gnt_persistent);
+			be->blkif->vbd.feature_gnt_persistent_parm);
 	if (err) {
 		xenbus_dev_fatal(dev, err, "writing %s/feature-persistent",
 				 dev->nodename);
@@ -1090,10 +1084,11 @@ static int connect_ring(struct backend_info *be)
 		xenbus_dev_fatal(dev, err, "unknown fe protocol %s", protocol);
 		return -ENOSYS;
 	}
-	if (blkif->vbd.feature_gnt_persistent)
-		blkif->vbd.feature_gnt_persistent =
-			xenbus_read_unsigned(dev->otherend,
-					"feature-persistent", 0);
+
+	blkif->vbd.feature_gnt_persistent_parm = feature_persistent;
+	blkif->vbd.feature_gnt_persistent =
+		blkif->vbd.feature_gnt_persistent_parm &&
+		xenbus_read_unsigned(dev->otherend, "feature-persistent", 0);
 
 	blkif->vbd.overflow_max_grants = 0;