Merge tag 'for-linus-5.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - decouple the PV interface from kernel internals in the Xen
   scsifront/scsiback pv drivers

 - harden the Xen scsifront PV driver against a malicious backend driver

 - simplify Xen PV frontend driver ring page setup

 - support Xen setups with multiple domains created at boot time to
   tolerate Xenstore coming up late

 - two small cleanup patches

* tag 'for-linus-5.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits)
  xen: add support for initializing xenstore later as HVM domain
  xen: sync xs_wire.h header with upstream xen
  x86: xen: remove STACK_FRAME_NON_STANDARD from xen_cpuid
  xen-blk{back,front}: Update contact points for buffer_squeeze_duration_ms and feature_persistent
  xen/xenbus: eliminate xenbus_grant_ring()
  xen/sndfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/usbfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/scsifront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/pcifront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/drmfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/tpmfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/netfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/blkfront: use xenbus_setup_ring() and xenbus_teardown_ring()
  xen/xenbus: add xenbus_setup_ring() service function
  xen: update ring.h
  xen/shbuf: switch xen-front-pgdir-shbuf to use INVALID_GRANT_REF
  xen/dmabuf: switch gntdev-dmabuf to use INVALID_GRANT_REF
  xen/sound: switch xen_snd_front to use INVALID_GRANT_REF
  xen/drm: switch xen_drm_front to use INVALID_GRANT_REF
  xen/usb: switch xen-hcd to use INVALID_GRANT_REF
  ...

1 files changed, 17 insertions, 40 deletions

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 0f3f5238f7bc..55e004d03ced 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -229,8 +229,6 @@ static unsigned int nr_minors;
 static unsigned long *minors;
 static DEFINE_SPINLOCK(minor_lock);
 
-#define GRANT_INVALID_REF	0
-
 #define PARTS_PER_DISK		16
 #define PARTS_PER_EXT_DISK      256
 
@@ -321,7 +319,7 @@ static int fill_grant_buffer(struct blkfront_ring_info *rinfo, int num)
 			gnt_list_entry->page = granted_page;
 		}
 
-		gnt_list_entry->gref = GRANT_INVALID_REF;
+		gnt_list_entry->gref = INVALID_GRANT_REF;
 		list_add(&gnt_list_entry->node, &rinfo->grants);
 		i++;
 	}
@@ -350,7 +348,7 @@ static struct grant *get_free_grant(struct blkfront_ring_info *rinfo)
 					  node);
 	list_del(&gnt_list_entry->node);
 
-	if (gnt_list_entry->gref != GRANT_INVALID_REF)
+	if (gnt_list_entry->gref != INVALID_GRANT_REF)
 		rinfo->persistent_gnts_c--;
 
 	return gnt_list_entry;
@@ -372,7 +370,7 @@ static struct grant *get_grant(grant_ref_t *gref_head,
 	struct grant *gnt_list_entry = get_free_grant(rinfo);
 	struct blkfront_info *info = rinfo->dev_info;
 
-	if (gnt_list_entry->gref != GRANT_INVALID_REF)
+	if (gnt_list_entry->gref != INVALID_GRANT_REF)
 		return gnt_list_entry;
 
 	/* Assign a gref to this page */
@@ -396,7 +394,7 @@ static struct grant *get_indirect_grant(grant_ref_t *gref_head,
 	struct grant *gnt_list_entry = get_free_grant(rinfo);
 	struct blkfront_info *info = rinfo->dev_info;
 
-	if (gnt_list_entry->gref != GRANT_INVALID_REF)
+	if (gnt_list_entry->gref != INVALID_GRANT_REF)
 		return gnt_list_entry;
 
 	/* Assign a gref to this page */
@@ -1221,7 +1219,7 @@ static void blkif_free_ring(struct blkfront_ring_info *rinfo)
 		list_for_each_entry_safe(persistent_gnt, n,
 					 &rinfo->grants, node) {
 			list_del(&persistent_gnt->node);
-			if (persistent_gnt->gref != GRANT_INVALID_REF) {
+			if (persistent_gnt->gref != INVALID_GRANT_REF) {
 				gnttab_end_foreign_access(persistent_gnt->gref,
 							  0UL);
 				rinfo->persistent_gnts_c--;
@@ -1282,15 +1280,8 @@ free_shadow:
 	flush_work(&rinfo->work);
 
 	/* Free resources associated with old device channel. */
-	for (i = 0; i < info->nr_ring_pages; i++) {
-		if (rinfo->ring_ref[i] != GRANT_INVALID_REF) {
-			gnttab_end_foreign_access(rinfo->ring_ref[i], 0);
-			rinfo->ring_ref[i] = GRANT_INVALID_REF;
-		}
-	}
-	free_pages_exact(rinfo->ring.sring,
-			 info->nr_ring_pages * XEN_PAGE_SIZE);
-	rinfo->ring.sring = NULL;
+	xenbus_teardown_ring((void **)&rinfo->ring.sring, info->nr_ring_pages,
+			     rinfo->ring_ref);
 
 	if (rinfo->irq)
 		unbind_from_irqhandler(rinfo->irq, rinfo);
@@ -1475,7 +1466,7 @@ static int blkif_completion(unsigned long *id,
 			 * to the tail of the list, so it will not be picked
 			 * again unless we run out of persistent grants.
 			 */
-			s->grants_used[i]->gref = GRANT_INVALID_REF;
+			s->grants_used[i]->gref = INVALID_GRANT_REF;
 			list_add_tail(&s->grants_used[i]->node, &rinfo->grants);
 		}
 	}
@@ -1500,7 +1491,7 @@ static int blkif_completion(unsigned long *id,
 					indirect_page = s->indirect_grants[i]->page;
 					list_add(&indirect_page->lru, &rinfo->indirect_pages);
 				}
-				s->indirect_grants[i]->gref = GRANT_INVALID_REF;
+				s->indirect_grants[i]->gref = INVALID_GRANT_REF;
 				list_add_tail(&s->indirect_grants[i]->node, &rinfo->grants);
 			}
 		}
@@ -1681,30 +1672,16 @@ static int setup_blkring(struct xenbus_device *dev,
 			 struct blkfront_ring_info *rinfo)
 {
 	struct blkif_sring *sring;
-	int err, i;
+	int err;
 	struct blkfront_info *info = rinfo->dev_info;
 	unsigned long ring_size = info->nr_ring_pages * XEN_PAGE_SIZE;
-	grant_ref_t gref[XENBUS_MAX_RING_GRANTS];
-
-	for (i = 0; i < info->nr_ring_pages; i++)
-		rinfo->ring_ref[i] = GRANT_INVALID_REF;
 
-	sring = alloc_pages_exact(ring_size, GFP_NOIO);
-	if (!sring) {
-		xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
-		return -ENOMEM;
-	}
-	SHARED_RING_INIT(sring);
-	FRONT_RING_INIT(&rinfo->ring, sring, ring_size);
-
-	err = xenbus_grant_ring(dev, rinfo->ring.sring, info->nr_ring_pages, gref);
-	if (err < 0) {
-		free_pages_exact(sring, ring_size);
-		rinfo->ring.sring = NULL;
+	err = xenbus_setup_ring(dev, GFP_NOIO, (void **)&sring,
+				info->nr_ring_pages, rinfo->ring_ref);
+	if (err)
 		goto fail;
-	}
-	for (i = 0; i < info->nr_ring_pages; i++)
-		rinfo->ring_ref[i] = gref[i];
+
+	XEN_FRONT_RING_INIT(&rinfo->ring, sring, ring_size);
 
 	err = xenbus_alloc_evtchn(dev, &rinfo->evtchn);
 	if (err)
@@ -2544,13 +2521,13 @@ static void purge_persistent_grants(struct blkfront_info *info)
 
 		list_for_each_entry_safe(gnt_list_entry, tmp, &rinfo->grants,
 					 node) {
-			if (gnt_list_entry->gref == GRANT_INVALID_REF ||
+			if (gnt_list_entry->gref == INVALID_GRANT_REF ||
 			    !gnttab_try_end_foreign_access(gnt_list_entry->gref))
 				continue;
 
 			list_del(&gnt_list_entry->node);
 			rinfo->persistent_gnts_c--;
-			gnt_list_entry->gref = GRANT_INVALID_REF;
+			gnt_list_entry->gref = INVALID_GRANT_REF;
 			list_add_tail(&gnt_list_entry->node, &grants);
 		}