Merge tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:

 - Improve balloon driver memory hotplug placement.

 - Use unpopulated hotplugged memory for foreign pages (if
   supported/enabled).

 - Support 64 KiB guest pages on arm64.

 - CPU hotplug support on arm/arm64.

* tag 'for-linus-4.4-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (44 commits)
  xen: fix the check of e_pfn in xen_find_pfn_range
  x86/xen: add reschedule point when mapping foreign GFNs
  xen/arm: don't try to re-register vcpu_info on cpu_hotplug.
  xen, cpu_hotplug: call device_offline instead of cpu_down
  xen/arm: Enable cpu_hotplug.c
  xenbus: Support multiple grants ring with 64KB
  xen/grant-table: Add an helper to iterate over a specific number of grants
  xen/xenbus: Rename *RING_PAGE* to *RING_GRANT*
  xen/arm: correct comment in enlighten.c
  xen/gntdev: use types from linux/types.h in userspace headers
  xen/gntalloc: use types from linux/types.h in userspace headers
  xen/balloon: Use the correct sizeof when declaring frame_list
  xen/swiotlb: Add support for 64KB page granularity
  xen/swiotlb: Pass addresses rather than frame numbers to xen_arch_need_swiotlb
  arm/xen: Add support for 64KB page granularity
  xen/privcmd: Add support for Linux 64KB page granularity
  net/xen-netback: Make it running on 64KB page granularity
  net/xen-netfront: Make it running on 64KB page granularity
  block/xen-blkback: Make it running on 64KB page granularity
  block/xen-blkfront: Make it running on 64KB page granularity
  ...

12 files changed, 497 insertions, 236 deletions

diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index e293bc507cbc..aa8a7f71f310 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -1,6 +1,4 @@
-ifeq ($(filter y, $(CONFIG_ARM) $(CONFIG_ARM64)),)
 obj-$(CONFIG_HOTPLUG_CPU)		+= cpu_hotplug.o
-endif
 obj-$(CONFIG_X86)			+= fallback.o
 obj-y	+= grant-table.o features.o balloon.o manage.o preempt.o
 obj-y	+= events/
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index c79329fcfa78..12eab503efd1 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -54,6 +54,8 @@
 #include <linux/memory.h>
 #include <linux/memory_hotplug.h>
 #include <linux/percpu-defs.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
 
 #include <asm/page.h>
 #include <asm/pgalloc.h>
@@ -70,16 +72,64 @@
 #include <xen/features.h>
 #include <xen/page.h>
 
+static int xen_hotplug_unpopulated;
+
+#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
+
+static int zero;
+static int one = 1;
+
+static struct ctl_table balloon_table[] = {
+	{
+		.procname	= "hotplug_unpopulated",
+		.data		= &xen_hotplug_unpopulated,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1         = &zero,
+		.extra2         = &one,
+	},
+	{ }
+};
+
+static struct ctl_table balloon_root[] = {
+	{
+		.procname	= "balloon",
+		.mode		= 0555,
+		.child		= balloon_table,
+	},
+	{ }
+};
+
+static struct ctl_table xen_root[] = {
+	{
+		.procname	= "xen",
+		.mode		= 0555,
+		.child		= balloon_root,
+	},
+	{ }
+};
+
+#endif
+
+/*
+ * Use one extent per PAGE_SIZE to avoid to break down the page into
+ * multiple frame.
+ */
+#define EXTENT_ORDER (fls(XEN_PFN_PER_PAGE) - 1)
+
 /*
  * balloon_process() state:
  *
  * BP_DONE: done or nothing to do,
+ * BP_WAIT: wait to be rescheduled,
  * BP_EAGAIN: error, go to sleep,
  * BP_ECANCELED: error, balloon operation canceled.
  */
 
 enum bp_state {
 	BP_DONE,
+	BP_WAIT,
 	BP_EAGAIN,
 	BP_ECANCELED
 };
@@ -91,11 +141,12 @@ struct balloon_stats balloon_stats;
 EXPORT_SYMBOL_GPL(balloon_stats);
 
 /* We increase/decrease in batches which fit in a page */
-static xen_pfn_t frame_list[PAGE_SIZE / sizeof(unsigned long)];
+static xen_pfn_t frame_list[PAGE_SIZE / sizeof(xen_pfn_t)];
 
 
 /* List of ballooned pages, threaded through the mem_map array. */
 static LIST_HEAD(ballooned_pages);
+static DECLARE_WAIT_QUEUE_HEAD(balloon_wq);
 
 /* Main work function, always executed in process context. */
 static void balloon_process(struct work_struct *work);
@@ -124,6 +175,7 @@ static void __balloon_append(struct page *page)
 		list_add(&page->lru, &ballooned_pages);
 		balloon_stats.balloon_low++;
 	}
+	wake_up(&balloon_wq);
 }
 
 static void balloon_append(struct page *page)
@@ -133,17 +185,16 @@ static void balloon_append(struct page *page)
 }
 
 /* balloon_retrieve: rescue a page from the balloon, if it is not empty. */
-static struct page *balloon_retrieve(bool prefer_highmem)
+static struct page *balloon_retrieve(bool require_lowmem)
 {
 	struct page *page;
 
 	if (list_empty(&ballooned_pages))
 		return NULL;
 
-	if (prefer_highmem)
-		page = list_entry(ballooned_pages.prev, struct page, lru);
-	else
-		page = list_entry(ballooned_pages.next, struct page, lru);
+	page = list_entry(ballooned_pages.next, struct page, lru);
+	if (require_lowmem && PageHighMem(page))
+		return NULL;
 	list_del(&page->lru);
 
 	if (PageHighMem(page))
@@ -166,6 +217,9 @@ static struct page *balloon_next_page(struct page *page)
 
 static enum bp_state update_schedule(enum bp_state state)
 {
+	if (state == BP_WAIT)
+		return BP_WAIT;
+
 	if (state == BP_ECANCELED)
 		return BP_ECANCELED;
 
@@ -193,43 +247,75 @@ static enum bp_state update_schedule(enum bp_state state)
 }
 
 #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-static long current_credit(void)
+static struct resource *additional_memory_resource(phys_addr_t size)
 {
-	return balloon_stats.target_pages - balloon_stats.current_pages -
-		balloon_stats.hotplug_pages;
+	struct resource *res;
+	int ret;
+
+	res = kzalloc(sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return NULL;
+
+	res->name = "System RAM";
+	res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+
+	ret = allocate_resource(&iomem_resource, res,
+				size, 0, -1,
+				PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL);
+	if (ret < 0) {
+		pr_err("Cannot allocate new System RAM resource\n");
+		kfree(res);
+		return NULL;
+	}
+
+	return res;
 }
 
-static bool balloon_is_inflated(void)
+static void release_memory_resource(struct resource *resource)
 {
-	if (balloon_stats.balloon_low || balloon_stats.balloon_high ||
-			balloon_stats.balloon_hotplug)
-		return true;
-	else
-		return false;
-}
+	if (!resource)
+		return;
 
-/*
- * reserve_additional_memory() adds memory region of size >= credit above
- * max_pfn. New region is section aligned and size is modified to be multiple
- * of section size. Those features allow optimal use of address space and
- * establish proper alignment when this function is called first time after
- * boot (last section not fully populated at boot time contains unused memory
- * pages with PG_reserved bit not set; online_pages_range() does not allow page
- * onlining in whole range if first onlined page does not have PG_reserved
- * bit set). Real size of added memory is established at page onlining stage.
- */
+	/*
+	 * No need to reset region to identity mapped since we now
+	 * know that no I/O can be in this region
+	 */
+	release_resource(resource);
+	kfree(resource);
+}
 
-static enum bp_state reserve_additional_memory(long credit)
+static enum bp_state reserve_additional_memory(void)
 {
+	long credit;
+	struct resource *resource;
 	int nid, rc;
-	u64 hotplug_start_paddr;
-	unsigned long balloon_hotplug = credit;
+	unsigned long balloon_hotplug;
+
+	credit = balloon_stats.target_pages + balloon_stats.target_unpopulated
+		- balloon_stats.total_pages;
+
+	/*
+	 * Already hotplugged enough pages?  Wait for them to be
+	 * onlined.
+	 */
+	if (credit <= 0)
+		return BP_WAIT;
 
-	hotplug_start_paddr = PFN_PHYS(SECTION_ALIGN_UP(max_pfn));
-	balloon_hotplug = round_up(balloon_hotplug, PAGES_PER_SECTION);
-	nid = memory_add_physaddr_to_nid(hotplug_start_paddr);
+	balloon_hotplug = round_up(credit, PAGES_PER_SECTION);
+
+	resource = additional_memory_resource(balloon_hotplug * PAGE_SIZE);
+	if (!resource)
+		goto err;
+
+	nid = memory_add_physaddr_to_nid(resource->start);
 
 #ifdef CONFIG_XEN_HAVE_PVMMU
+	/*
+	 * We don't support PV MMU when Linux and Xen is using
+	 * different page granularity.
+	 */
+	BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
+
         /*
          * add_memory() will build page tables for the new memory so
          * the p2m must contain invalid entries so the correct
@@ -242,29 +328,28 @@ static enum bp_state reserve_additional_memory(long credit)
 	if (!xen_feature(XENFEAT_auto_translated_physmap)) {
 		unsigned long pfn, i;
 
-		pfn = PFN_DOWN(hotplug_start_paddr);
+		pfn = PFN_DOWN(resource->start);
 		for (i = 0; i < balloon_hotplug; i++) {
 			if (!set_phys_to_machine(pfn + i, INVALID_P2M_ENTRY)) {
 				pr_warn("set_phys_to_machine() failed, no memory added\n");
-				return BP_ECANCELED;
+				goto err;
 			}
                 }
 	}
 #endif
 
-	rc = add_memory(nid, hotplug_start_paddr, balloon_hotplug << PAGE_SHIFT);
-
+	rc = add_memory_resource(nid, resource);
 	if (rc) {
 		pr_warn("Cannot add additional memory (%i)\n", rc);
-		return BP_ECANCELED;
+		goto err;
 	}
 
-	balloon_hotplug -= credit;
+	balloon_stats.total_pages += balloon_hotplug;
 
-	balloon_stats.hotplug_pages += credit;
-	balloon_stats.balloon_hotplug = balloon_hotplug;
-
-	return BP_DONE;
+	return BP_WAIT;
+  err:
+	release_memory_resource(resource);
+	return BP_ECANCELED;
 }
 
 static void xen_online_page(struct page *page)
@@ -275,11 +360,6 @@ static void xen_online_page(struct page *page)
 
 	__balloon_append(page);
 
-	if (balloon_stats.hotplug_pages)
-		--balloon_stats.hotplug_pages;
-	else
-		--balloon_stats.balloon_hotplug;
-
 	mutex_unlock(&balloon_mutex);
 }
 
@@ -296,53 +376,34 @@ static struct notifier_block xen_memory_nb = {
 	.priority = 0
 };
 #else
-static long current_credit(void)
+static enum bp_state reserve_additional_memory(void)
 {
-	unsigned long target = balloon_stats.target_pages;
-
-	target = min(target,
-		     balloon_stats.current_pages +
-		     balloon_stats.balloon_low +
-		     balloon_stats.balloon_high);
-
-	return target - balloon_stats.current_pages;
+	balloon_stats.target_pages = balloon_stats.current_pages;
+	return BP_ECANCELED;
 }
+#endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */
 
-static bool balloon_is_inflated(void)
+static long current_credit(void)
 {
-	if (balloon_stats.balloon_low || balloon_stats.balloon_high)
-		return true;
-	else
-		return false;
+	return balloon_stats.target_pages - balloon_stats.current_pages;
 }
 
-static enum bp_state reserve_additional_memory(long credit)
+static bool balloon_is_inflated(void)
 {
-	balloon_stats.target_pages = balloon_stats.current_pages;
-	return BP_DONE;
+	return balloon_stats.balloon_low || balloon_stats.balloon_high;
 }
-#endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */
 
 static enum bp_state increase_reservation(unsigned long nr_pages)
 {
 	int rc;
-	unsigned long  pfn, i;
+	unsigned long i;
 	struct page   *page;
 	struct xen_memory_reservation reservation = {
 		.address_bits = 0,
-		.extent_order = 0,
+		.extent_order = EXTENT_ORDER,
 		.domid        = DOMID_SELF
 	};
 
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-	if (!balloon_stats.balloon_low && !balloon_stats.balloon_high) {
-		nr_pages = min(nr_pages, balloon_stats.balloon_hotplug);
-		balloon_stats.hotplug_pages += nr_pages;
-		balloon_stats.balloon_hotplug -= nr_pages;
-		return BP_DONE;
-	}
-#endif
-
 	if (nr_pages > ARRAY_SIZE(frame_list))
 		nr_pages = ARRAY_SIZE(frame_list);
 
@@ -352,7 +413,11 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
 			nr_pages = i;
 			break;
 		}
-		frame_list[i] = page_to_pfn(page);
+
+		/* XENMEM_populate_physmap requires a PFN based on Xen
+		 * granularity.
+		 */
+		frame_list[i] = page_to_xen_pfn(page);
 		page = balloon_next_page(page);
 	}
 
@@ -366,10 +431,16 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
 		page = balloon_retrieve(false);
 		BUG_ON(page == NULL);
 
-		pfn = page_to_pfn(page);
-
 #ifdef CONFIG_XEN_HAVE_PVMMU
+		/*
+		 * We don't support PV MMU when Linux and Xen is using
+		 * different page granularity.
+		 */
+		BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
+
 		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+			unsigned long pfn = page_to_pfn(page);
+
 			set_phys_to_machine(pfn, frame_list[i]);
 
 			/* Link back into the page tables if not highmem. */
@@ -396,23 +467,15 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
 static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 {
 	enum bp_state state = BP_DONE;
-	unsigned long  pfn, i;
-	struct page   *page;
+	unsigned long i;
+	struct page *page, *tmp;
 	int ret;
 	struct xen_memory_reservation reservation = {
 		.address_bits = 0,
-		.extent_order = 0,
+		.extent_order = EXTENT_ORDER,
 		.domid        = DOMID_SELF
 	};
-
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-	if (balloon_stats.hotplug_pages) {
-		nr_pages = min(nr_pages, balloon_stats.hotplug_pages);
-		balloon_stats.hotplug_pages -= nr_pages;
-		balloon_stats.balloon_hotplug += nr_pages;
-		return BP_DONE;
-	}
-#endif
+	LIST_HEAD(pages);
 
 	if (nr_pages > ARRAY_SIZE(frame_list))
 		nr_pages = ARRAY_SIZE(frame_list);
@@ -425,8 +488,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 			break;
 		}
 		scrub_page(page);
-
-		frame_list[i] = page_to_pfn(page);
+		list_add(&page->lru, &pages);
 	}
 
 	/*
@@ -438,14 +500,25 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 	 */
 	kmap_flush_unused();
 
-	/* Update direct mapping, invalidate P2M, and add to balloon. */
-	for (i = 0; i < nr_pages; i++) {
-		pfn = frame_list[i];
-		frame_list[i] = pfn_to_gfn(pfn);
-		page = pfn_to_page(pfn);
+	/*
+	 * Setup the frame, update direct mapping, invalidate P2M,
+	 * and add to balloon.
+	 */
+	i = 0;
+	list_for_each_entry_safe(page, tmp, &pages, lru) {
+		/* XENMEM_decrease_reservation requires a GFN */
+		frame_list[i++] = xen_page_to_gfn(page);
 
 #ifdef CONFIG_XEN_HAVE_PVMMU
+		/*
+		 * We don't support PV MMU when Linux and Xen is using
+		 * different page granularity.
+		 */
+		BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
+
 		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+			unsigned long pfn = page_to_pfn(page);
+
 			if (!PageHighMem(page)) {
 				ret = HYPERVISOR_update_va_mapping(
 						(unsigned long)__va(pfn << PAGE_SHIFT),
@@ -455,6 +528,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 			__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
 		}
 #endif
+		list_del(&page->lru);
 
 		balloon_append(page);
 	}
@@ -492,7 +566,7 @@ static void balloon_process(struct work_struct *work)
 			if (balloon_is_inflated())
 				state = increase_reservation(credit);
 			else
-				state = reserve_additional_memory(credit);
+				state = reserve_additional_memory();
 		}
 
 		if (credit < 0)
@@ -520,41 +594,71 @@ void balloon_set_new_target(unsigned long target)
 }
 EXPORT_SYMBOL_GPL(balloon_set_new_target);
 
+static int add_ballooned_pages(int nr_pages)
+{
+	enum bp_state st;
+
+	if (xen_hotplug_unpopulated) {
+		st = reserve_additional_memory();
+		if (st != BP_ECANCELED) {
+			mutex_unlock(&balloon_mutex);
+			wait_event(balloon_wq,
+				   !list_empty(&ballooned_pages));
+			mutex_lock(&balloon_mutex);
+			return 0;
+		}
+	}
+
+	st = decrease_reservation(nr_pages, GFP_USER);
+	if (st != BP_DONE)
+		return -ENOMEM;
+
+	return 0;
+}
+
 /**
  * alloc_xenballooned_pages - get pages that have been ballooned out
  * @nr_pages: Number of pages to get
  * @pages: pages returned
- * @highmem: allow highmem pages
  * @return 0 on success, error otherwise
  */
-int alloc_xenballooned_pages(int nr_pages, struct page **pages, bool highmem)
+int alloc_xenballooned_pages(int nr_pages, struct page **pages)
 {
 	int pgno = 0;
 	struct page *page;
+	int ret;
+
 	mutex_lock(&balloon_mutex);
+
+	balloon_stats.target_unpopulated += nr_pages;
+
 	while (pgno < nr_pages) {
-		page = balloon_retrieve(highmem);
-		if (page && (highmem || !PageHighMem(page))) {
+		page = balloon_retrieve(true);
+		if (page) {
 			pages[pgno++] = page;
+#ifdef CONFIG_XEN_HAVE_PVMMU
+			/*
+			 * We don't support PV MMU when Linux and Xen is using
+			 * different page granularity.
+			 */
+			BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
+
+			ret = xen_alloc_p2m_entry(page_to_pfn(page));
+			if (ret < 0)
+				goto out_undo;
+#endif
 		} else {
-			enum bp_state st;
-			if (page)
-				balloon_append(page);
-			st = decrease_reservation(nr_pages - pgno,
-					highmem ? GFP_HIGHUSER : GFP_USER);
-			if (st != BP_DONE)
+			ret = add_ballooned_pages(nr_pages - pgno);
+			if (ret < 0)
 				goto out_undo;
 		}
 	}
 	mutex_unlock(&balloon_mutex);
 	return 0;
  out_undo:
-	while (pgno)
-		balloon_append(pages[--pgno]);
-	/* Free the memory back to the kernel soon */
-	schedule_delayed_work(&balloon_worker, 0);
 	mutex_unlock(&balloon_mutex);
-	return -ENOMEM;
+	free_xenballooned_pages(pgno, pages);
+	return ret;
 }
 EXPORT_SYMBOL(alloc_xenballooned_pages);
 
@@ -574,6 +678,8 @@ void free_xenballooned_pages(int nr_pages, struct page **pages)
 			balloon_append(pages[i]);
 	}
 
+	balloon_stats.target_unpopulated -= nr_pages;
+
 	/* The balloon may be too large now. Shrink it if needed. */
 	if (current_credit())
 		schedule_delayed_work(&balloon_worker, 0);
@@ -602,6 +708,8 @@ static void __init balloon_add_region(unsigned long start_pfn,
 		   don't subtract from it. */
 		__balloon_append(page);
 	}
+
+	balloon_stats.total_pages += extra_pfn_end - start_pfn;
 }
 
 static int __init balloon_init(void)
@@ -619,6 +727,7 @@ static int __init balloon_init(void)
 	balloon_stats.target_pages  = balloon_stats.current_pages;
 	balloon_stats.balloon_low   = 0;
 	balloon_stats.balloon_high  = 0;
+	balloon_stats.total_pages   = balloon_stats.current_pages;
 
 	balloon_stats.schedule_delay = 1;
 	balloon_stats.max_schedule_delay = 32;
@@ -626,11 +735,9 @@ static int __init balloon_init(void)
 	balloon_stats.max_retry_count = RETRY_UNLIMITED;
 
 #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-	balloon_stats.hotplug_pages = 0;
-	balloon_stats.balloon_hotplug = 0;
-
 	set_online_page_callback(&xen_online_page);
 	register_memory_notifier(&xen_memory_nb);
+	register_sysctl_table(xen_root);
 #endif
 
 	/*
diff --git a/drivers/xen/biomerge.c b/drivers/xen/biomerge.c
index 8ae2fc90e1ea..4da69dbf7dca 100644
--- a/drivers/xen/biomerge.c
+++ b/drivers/xen/biomerge.c
@@ -6,10 +6,18 @@
 bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 			       const struct bio_vec *vec2)
 {
+#if XEN_PAGE_SIZE == PAGE_SIZE
 	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
 	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(vec2->bv_page));
 
 	return __BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&
 		((bfn1 == bfn2) || ((bfn1+1) == bfn2));
+#else
+	/*
+	 * XXX: Add support for merging bio_vec when using different page
+	 * size in Xen and Linux.
+	 */
+	return 0;
+#endif
 }
 EXPORT_SYMBOL(xen_biovec_phys_mergeable);
diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
index cc6513a176b0..5676aefdf2bc 100644
--- a/drivers/xen/cpu_hotplug.c
+++ b/drivers/xen/cpu_hotplug.c
@@ -11,15 +11,20 @@
 static void enable_hotplug_cpu(int cpu)
 {
 	if (!cpu_present(cpu))
-		arch_register_cpu(cpu);
+		xen_arch_register_cpu(cpu);
 
 	set_cpu_present(cpu, true);
 }
 
 static void disable_hotplug_cpu(int cpu)
 {
+	if (cpu_online(cpu)) {
+		lock_device_hotplug();
+		device_offline(get_cpu_device(cpu));
+		unlock_device_hotplug();
+	}
 	if (cpu_present(cpu))
-		arch_unregister_cpu(cpu);
+		xen_arch_unregister_cpu(cpu);
 
 	set_cpu_present(cpu, false);
 }
@@ -55,7 +60,6 @@ static void vcpu_hotplug(unsigned int cpu)
 		enable_hotplug_cpu(cpu);
 		break;
 	case 0:
-		(void)cpu_down(cpu);
 		disable_hotplug_cpu(cpu);
 		break;
 	default:
@@ -102,7 +106,11 @@ static int __init setup_vcpu_hotplug_event(void)
 	static struct notifier_block xsn_cpu = {
 		.notifier_call = setup_cpu_watcher };
 
+#ifdef CONFIG_X86
 	if (!xen_pv_domain())
+#else
+	if (!xen_domain())
+#endif
 		return -ENODEV;
 
 	register_xenstore_notifier(&xsn_cpu);
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 6cd5e65c4aff..849500e4e14d 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -40,11 +40,11 @@
 #include <asm/idle.h>
 #include <asm/io_apic.h>
 #include <asm/xen/pci.h>
-#include <xen/page.h>
 #endif
 #include <asm/sync_bitops.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
+#include <xen/page.h>
 
 #include <xen/xen.h>
 #include <xen/hvm.h>
diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c
index 1d4baf56c36b..e3e9e3d46d1b 100644
--- a/drivers/xen/events/events_fifo.c
+++ b/drivers/xen/events/events_fifo.c
@@ -54,7 +54,7 @@
 
 #include "events_internal.h"
 
-#define EVENT_WORDS_PER_PAGE (PAGE_SIZE / sizeof(event_word_t))
+#define EVENT_WORDS_PER_PAGE (XEN_PAGE_SIZE / sizeof(event_word_t))
 #define MAX_EVENT_ARRAY_PAGES (EVTCHN_FIFO_NR_CHANNELS / EVENT_WORDS_PER_PAGE)
 
 struct evtchn_fifo_queue {
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 62f591f8763c..c49f79ed58c5 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -642,7 +642,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr)
 	if (xen_auto_xlat_grant_frames.count)
 		return -EINVAL;
 
-	vaddr = xen_remap(addr, PAGE_SIZE * max_nr_gframes);
+	vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes);
 	if (vaddr == NULL) {
 		pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n",
 			&addr);
@@ -654,7 +654,7 @@ int gnttab_setup_auto_xlat_frames(phys_addr_t addr)
 		return -ENOMEM;
 	}
 	for (i = 0; i < max_nr_gframes; i++)
-		pfn[i] = PFN_DOWN(addr) + i;
+		pfn[i] = XEN_PFN_DOWN(addr) + i;
 
 	xen_auto_xlat_grant_frames.vaddr = vaddr;
 	xen_auto_xlat_grant_frames.pfn = pfn;
@@ -687,7 +687,7 @@ int gnttab_alloc_pages(int nr_pages, struct page **pages)
 	int i;
 	int ret;
 
-	ret = alloc_xenballooned_pages(nr_pages, pages, false);
+	ret = alloc_xenballooned_pages(nr_pages, pages);
 	if (ret < 0)
 		return ret;
 
@@ -776,6 +776,54 @@ void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count)
 }
 EXPORT_SYMBOL_GPL(gnttab_batch_copy);
 
+void gnttab_foreach_grant_in_range(struct page *page,
+				   unsigned int offset,
+				   unsigned int len,
+				   xen_grant_fn_t fn,
+				   void *data)
+{
+	unsigned int goffset;
+	unsigned int glen;
+	unsigned long xen_pfn;
+
+	len = min_t(unsigned int, PAGE_SIZE - offset, len);
+	goffset = xen_offset_in_page(offset);
+
+	xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset);
+
+	while (len) {
+		glen = min_t(unsigned int, XEN_PAGE_SIZE - goffset, len);
+		fn(pfn_to_gfn(xen_pfn), goffset, glen, data);
+
+		goffset = 0;
+		xen_pfn++;
+		len -= glen;
+	}
+}
+EXPORT_SYMBOL_GPL(gnttab_foreach_grant_in_range);
+
+void gnttab_foreach_grant(struct page **pages,
+			  unsigned int nr_grefs,
+			  xen_grant_fn_t fn,
+			  void *data)
+{
+	unsigned int goffset = 0;
+	unsigned long xen_pfn = 0;
+	unsigned int i;
+
+	for (i = 0; i < nr_grefs; i++) {
+		if ((i % XEN_PFN_PER_PAGE) == 0) {
+			xen_pfn = page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);
+			goffset = 0;
+		}
+
+		fn(pfn_to_gfn(xen_pfn), goffset, XEN_PAGE_SIZE, data);
+
+		goffset += XEN_PAGE_SIZE;
+		xen_pfn++;
+	}
+}
+
 int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
 		    struct gnttab_map_grant_ref *kmap_ops,
 		    struct page **pages, unsigned int count)
@@ -978,7 +1026,7 @@ static void gnttab_request_version(void)
 {
 	/* Only version 1 is used, which will always be available. */
 	grant_table_version = 1;
-	grefs_per_grant_frame = PAGE_SIZE / sizeof(struct grant_entry_v1);
+	grefs_per_grant_frame = XEN_PAGE_SIZE / sizeof(struct grant_entry_v1);
 	gnttab_interface = &gnttab_v1_ops;
 
 	pr_info("Grant tables using version %d layout\n", grant_table_version);
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index 5e9adac928e6..df2e6f783318 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -401,7 +401,7 @@ static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs)
 	if (pages == NULL)
 		return -ENOMEM;
 
-	rc = alloc_xenballooned_pages(numpgs, pages, 0);
+	rc = alloc_xenballooned_pages(numpgs, pages);
 	if (rc != 0) {
 		pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__,
 			numpgs, rc);
@@ -446,7 +446,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 		return -EINVAL;
 	}
 
-	nr_pages = m.num;
+	nr_pages = DIV_ROUND_UP(m.num, XEN_PFN_PER_PAGE);
 	if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT)))
 		return -EINVAL;
 
@@ -494,7 +494,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 			goto out_unlock;
 		}
 		if (xen_feature(XENFEAT_auto_translated_physmap)) {
-			ret = alloc_empty_pages(vma, m.num);
+			ret = alloc_empty_pages(vma, nr_pages);
 			if (ret < 0)
 				goto out_unlock;
 		} else
@@ -518,6 +518,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 	state.global_error  = 0;
 	state.version       = version;
 
+	BUILD_BUG_ON(((PAGE_SIZE / sizeof(xen_pfn_t)) % XEN_PFN_PER_PAGE) != 0);
 	/* mmap_batch_fn guarantees ret == 0 */
 	BUG_ON(traverse_pages_block(m.num, sizeof(xen_pfn_t),
 				    &pagelist, mmap_batch_fn, &state));
@@ -582,12 +583,13 @@ static void privcmd_close(struct vm_area_struct *vma)
 {
 	struct page **pages = vma->vm_private_data;
 	int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	int numgfns = (vma->vm_end - vma->vm_start) >> XEN_PAGE_SHIFT;
 	int rc;
 
 	if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages)
 		return;
 
-	rc = xen_unmap_domain_gfn_range(vma, numpgs, pages);
+	rc = xen_unmap_domain_gfn_range(vma, numgfns, pages);
 	if (rc == 0)
 		free_xenballooned_pages(numpgs, pages);
 	else
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 79bc4933b13e..7399782c0998 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -76,27 +76,27 @@ static unsigned long xen_io_tlb_nslabs;
 static u64 start_dma_addr;
 
 /*
- * Both of these functions should avoid PFN_PHYS because phys_addr_t
+ * Both of these functions should avoid XEN_PFN_PHYS because phys_addr_t
  * can be 32bit when dma_addr_t is 64bit leading to a loss in
  * information if the shift is done before casting to 64bit.
  */
 static inline dma_addr_t xen_phys_to_bus(phys_addr_t paddr)
 {
-	unsigned long bfn = pfn_to_bfn(PFN_DOWN(paddr));
-	dma_addr_t dma = (dma_addr_t)bfn << PAGE_SHIFT;
+	unsigned long bfn = pfn_to_bfn(XEN_PFN_DOWN(paddr));
+	dma_addr_t dma = (dma_addr_t)bfn << XEN_PAGE_SHIFT;
 
-	dma |= paddr & ~PAGE_MASK;
+	dma |= paddr & ~XEN_PAGE_MASK;
 
 	return dma;
 }
 
 static inline phys_addr_t xen_bus_to_phys(dma_addr_t baddr)
 {
-	unsigned long pfn = bfn_to_pfn(PFN_DOWN(baddr));
-	dma_addr_t dma = (dma_addr_t)pfn << PAGE_SHIFT;
+	unsigned long xen_pfn = bfn_to_pfn(XEN_PFN_DOWN(baddr));
+	dma_addr_t dma = (dma_addr_t)xen_pfn << XEN_PAGE_SHIFT;
 	phys_addr_t paddr = dma;
 
-	paddr |= baddr & ~PAGE_MASK;
+	paddr |= baddr & ~XEN_PAGE_MASK;
 
 	return paddr;
 }
@@ -106,7 +106,7 @@ static inline dma_addr_t xen_virt_to_bus(void *address)
 	return xen_phys_to_bus(virt_to_phys(address));
 }
 
-static int check_pages_physically_contiguous(unsigned long pfn,
+static int check_pages_physically_contiguous(unsigned long xen_pfn,
 					     unsigned int offset,
 					     size_t length)
 {
@@ -114,11 +114,11 @@ static int check_pages_physically_contiguous(unsigned long pfn,
 	int i;
 	int nr_pages;
 
-	next_bfn = pfn_to_bfn(pfn);
-	nr_pages = (offset + length + PAGE_SIZE-1) >> PAGE_SHIFT;
+	next_bfn = pfn_to_bfn(xen_pfn);
+	nr_pages = (offset + length + XEN_PAGE_SIZE-1) >> XEN_PAGE_SHIFT;
 
 	for (i = 1; i < nr_pages; i++) {
-		if (pfn_to_bfn(++pfn) != ++next_bfn)
+		if (pfn_to_bfn(++xen_pfn) != ++next_bfn)
 			return 0;
 	}
 	return 1;
@@ -126,28 +126,27 @@ static int check_pages_physically_contiguous(unsigned long pfn,
 
 static inline int range_straddles_page_boundary(phys_addr_t p, size_t size)
 {
-	unsigned long pfn = PFN_DOWN(p);
-	unsigned int offset = p & ~PAGE_MASK;
+	unsigned long xen_pfn = XEN_PFN_DOWN(p);
+	unsigned int offset = p & ~XEN_PAGE_MASK;
 
-	if (offset + size <= PAGE_SIZE)
+	if (offset + size <= XEN_PAGE_SIZE)
 		return 0;
-	if (check_pages_physically_contiguous(pfn, offset, size))
+	if (check_pages_physically_contiguous(xen_pfn, offset, size))
 		return 0;
 	return 1;
 }
 
 static int is_xen_swiotlb_buffer(dma_addr_t dma_addr)
 {
-	unsigned long bfn = PFN_DOWN(dma_addr);
-	unsigned long pfn = bfn_to_local_pfn(bfn);
-	phys_addr_t paddr;
+	unsigned long bfn = XEN_PFN_DOWN(dma_addr);
+	unsigned long xen_pfn = bfn_to_local_pfn(bfn);
+	phys_addr_t paddr = XEN_PFN_PHYS(xen_pfn);
 
 	/* If the address is outside our domain, it CAN
 	 * have the same virtual address as another address
 	 * in our domain. Therefore _only_ check address within our domain.
 	 */
-	if (pfn_valid(pfn)) {
-		paddr = PFN_PHYS(pfn);
+	if (pfn_valid(PFN_DOWN(paddr))) {
 		return paddr >= virt_to_phys(xen_io_tlb_start) &&
 		       paddr < virt_to_phys(xen_io_tlb_end);
 	}
@@ -392,7 +391,7 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
 	 */
 	if (dma_capable(dev, dev_addr, size) &&
 	    !range_straddles_page_boundary(phys, size) &&
-		!xen_arch_need_swiotlb(dev, PFN_DOWN(phys), PFN_DOWN(dev_addr)) &&
+		!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
 		!swiotlb_force) {
 		/* we are not interested in the dma_addr returned by
 		 * xen_dma_map_page, only in the potential cache flushes executed
@@ -551,7 +550,7 @@ xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
 		dma_addr_t dev_addr = xen_phys_to_bus(paddr);
 
 		if (swiotlb_force ||
-		    xen_arch_need_swiotlb(hwdev, PFN_DOWN(paddr), PFN_DOWN(dev_addr)) ||
+		    xen_arch_need_swiotlb(hwdev, paddr, dev_addr) ||
 		    !dma_capable(hwdev, dev_addr, sg->length) ||
 		    range_straddles_page_boundary(paddr, sg->length)) {
 			phys_addr_t map = swiotlb_tbl_map_single(hwdev,
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 2ba09c1195c8..056da6ee1a35 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -49,6 +49,10 @@
 
 #include "xenbus_probe.h"
 
+#define XENBUS_PAGES(_grants)	(DIV_ROUND_UP(_grants, XEN_PFN_PER_PAGE))
+
+#define XENBUS_MAX_RING_PAGES	(XENBUS_PAGES(XENBUS_MAX_RING_GRANTS))
+
 struct xenbus_map_node {
 	struct list_head next;
 	union {
@@ -57,10 +61,11 @@ struct xenbus_map_node {
 		} pv;
 		struct {
 			struct page *pages[XENBUS_MAX_RING_PAGES];
+			unsigned long addrs[XENBUS_MAX_RING_GRANTS];
 			void *addr;
 		} hvm;
 	};
-	grant_handle_t handles[XENBUS_MAX_RING_PAGES];
+	grant_handle_t handles[XENBUS_MAX_RING_GRANTS];
 	unsigned int   nr_handles;
 };
 
@@ -388,7 +393,7 @@ int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
 		}
 		grefs[i] = err;
 
-		vaddr = vaddr + PAGE_SIZE;
+		vaddr = vaddr + XEN_PAGE_SIZE;
 	}
 
 	return 0;
@@ -479,12 +484,12 @@ static int __xenbus_map_ring(struct xenbus_device *dev,
 			     unsigned int flags,
 			     bool *leaked)
 {
-	struct gnttab_map_grant_ref map[XENBUS_MAX_RING_PAGES];
-	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES];
+	struct gnttab_map_grant_ref map[XENBUS_MAX_RING_GRANTS];
+	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
 	int i, j;
 	int err = GNTST_okay;
 
-	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+	if (nr_grefs > XENBUS_MAX_RING_GRANTS)
 		return -EINVAL;
 
 	for (i = 0; i < nr_grefs; i++) {
@@ -540,22 +545,22 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
 {
 	struct xenbus_map_node *node;
 	struct vm_struct *area;
-	pte_t *ptes[XENBUS_MAX_RING_PAGES];
-	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
+	pte_t *ptes[XENBUS_MAX_RING_GRANTS];
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
 	int err = GNTST_okay;
 	int i;
 	bool leaked;
 
 	*vaddr = NULL;
 
-	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+	if (nr_grefs > XENBUS_MAX_RING_GRANTS)
 		return -EINVAL;
 
 	node = kzalloc(sizeof(*node), GFP_KERNEL);
 	if (!node)
 		return -ENOMEM;
 
-	area = alloc_vm_area(PAGE_SIZE * nr_grefs, ptes);
+	area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, ptes);
 	if (!area) {
 		kfree(node);
 		return -ENOMEM;
@@ -591,21 +596,44 @@ failed:
 	return err;
 }
 
+struct map_ring_valloc_hvm
+{
+	unsigned int idx;
+
+	/* Why do we need two arrays? See comment of __xenbus_map_ring */
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
+	unsigned long addrs[XENBUS_MAX_RING_GRANTS];
+};
+
+static void xenbus_map_ring_setup_grant_hvm(unsigned long gfn,
+					    unsigned int goffset,
+					    unsigned int len,
+					    void *data)
+{
+	struct map_ring_valloc_hvm *info = data;
+	unsigned long vaddr = (unsigned long)gfn_to_virt(gfn);
+
+	info->phys_addrs[info->idx] = vaddr;
+	info->addrs[info->idx] = vaddr;
+
+	info->idx++;
+}
+
 static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 				      grant_ref_t *gnt_ref,
 				      unsigned int nr_grefs,
 				      void **vaddr)
 {
 	struct xenbus_map_node *node;
-	int i;
 	int err;
 	void *addr;
 	bool leaked = false;
-	/* Why do we need two arrays? See comment of __xenbus_map_ring */
-	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
-	unsigned long addrs[XENBUS_MAX_RING_PAGES];
+	struct map_ring_valloc_hvm info = {
+		.idx = 0,
+	};
+	unsigned int nr_pages = XENBUS_PAGES(nr_grefs);
 
-	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+	if (nr_grefs > XENBUS_MAX_RING_GRANTS)
 		return -EINVAL;
 
 	*vaddr = NULL;
@@ -614,25 +642,22 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 	if (!node)
 		return -ENOMEM;
 
-	err = alloc_xenballooned_pages(nr_grefs, node->hvm.pages,
-				       false /* lowmem */);
+	err = alloc_xenballooned_pages(nr_pages, node->hvm.pages);
 	if (err)
 		goto out_err;
 
-	for (i = 0; i < nr_grefs; i++) {
-		unsigned long pfn = page_to_pfn(node->hvm.pages[i]);
-		phys_addrs[i] = (unsigned long)pfn_to_kaddr(pfn);
-		addrs[i] = (unsigned long)pfn_to_kaddr(pfn);
-	}
+	gnttab_foreach_grant(node->hvm.pages, nr_grefs,
+			     xenbus_map_ring_setup_grant_hvm,
+			     &info);
 
 	err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles,
-				phys_addrs, GNTMAP_host_map, &leaked);
+				info.phys_addrs, GNTMAP_host_map, &leaked);
 	node->nr_handles = nr_grefs;
 
 	if (err)
 		goto out_free_ballooned_pages;
 
-	addr = vmap(node->hvm.pages, nr_grefs, VM_MAP | VM_IOREMAP,
+	addr = vmap(node->hvm.pages, nr_pages, VM_MAP | VM_IOREMAP,
 		    PAGE_KERNEL);
 	if (!addr) {
 		err = -ENOMEM;
@@ -650,14 +675,13 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 
  out_xenbus_unmap_ring:
 	if (!leaked)
-		xenbus_unmap_ring(dev, node->handles, node->nr_handles,
-				  addrs);
+		xenbus_unmap_ring(dev, node->handles, nr_grefs, info.addrs);
 	else
 		pr_alert("leaking %p size %u page(s)",
-			 addr, nr_grefs);
+			 addr, nr_pages);
  out_free_ballooned_pages:
 	if (!leaked)
-		free_xenballooned_pages(nr_grefs, node->hvm.pages);
+		free_xenballooned_pages(nr_pages, node->hvm.pages);
  out_err:
 	kfree(node);
 	return err;
@@ -687,10 +711,10 @@ int xenbus_map_ring(struct xenbus_device *dev, grant_ref_t *gnt_refs,
 		    unsigned int nr_grefs, grant_handle_t *handles,
 		    unsigned long *vaddrs, bool *leaked)
 {
-	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
 	int i;
 
-	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+	if (nr_grefs > XENBUS_MAX_RING_GRANTS)
 		return -EINVAL;
 
 	for (i = 0; i < nr_grefs; i++)
@@ -723,7 +747,7 @@ EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
 static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
 {
 	struct xenbus_map_node *node;
-	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES];
+	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
 	unsigned int level;
 	int i;
 	bool leaked = false;
@@ -750,7 +774,7 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
 		unsigned long addr;
 
 		memset(&unmap[i], 0, sizeof(unmap[i]));
-		addr = (unsigned long)vaddr + (PAGE_SIZE * i);
+		addr = (unsigned long)vaddr + (XEN_PAGE_SIZE * i);
 		unmap[i].host_addr = arbitrary_virt_to_machine(
 			lookup_address(addr, &level)).maddr;
 		unmap[i].dev_bus_addr = 0;
@@ -783,13 +807,33 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
 	return err;
 }
 
+struct unmap_ring_vfree_hvm
+{
+	unsigned int idx;
+	unsigned long addrs[XENBUS_MAX_RING_GRANTS];
+};
+
+static void xenbus_unmap_ring_setup_grant_hvm(unsigned long gfn,
+					      unsigned int goffset,
+					      unsigned int len,
+					      void *data)
+{
+	struct unmap_ring_vfree_hvm *info = data;
+
+	info->addrs[info->idx] = (unsigned long)gfn_to_virt(gfn);
+
+	info->idx++;
+}
+
 static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
 {
 	int rv;
 	struct xenbus_map_node *node;
 	void *addr;
-	unsigned long addrs[XENBUS_MAX_RING_PAGES];
-	int i;
+	struct unmap_ring_vfree_hvm info = {
+		.idx = 0,
+	};
+	unsigned int nr_pages;
 
 	spin_lock(&xenbus_valloc_lock);
 	list_for_each_entry(node, &xenbus_valloc_pages, next) {
@@ -809,18 +853,20 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
 		return GNTST_bad_virt_addr;
 	}
 
-	for (i = 0; i < node->nr_handles; i++)
-		addrs[i] = (unsigned long)pfn_to_kaddr(page_to_pfn(node->hvm.pages[i]));
+	nr_pages = XENBUS_PAGES(node->nr_handles);
+
+	gnttab_foreach_grant(node->hvm.pages, node->nr_handles,
+			     xenbus_unmap_ring_setup_grant_hvm,
+			     &info);
 
 	rv = xenbus_unmap_ring(dev, node->handles, node->nr_handles,
-			       addrs);
+			       info.addrs);
 	if (!rv) {
 		vunmap(vaddr);
-		free_xenballooned_pages(node->nr_handles, node->hvm.pages);
+		free_xenballooned_pages(nr_pages, node->hvm.pages);
 	}
 	else
-		WARN(1, "Leaking %p, size %u page(s)\n", vaddr,
-		     node->nr_handles);
+		WARN(1, "Leaking %p, size %u page(s)\n", vaddr, nr_pages);
 
 	kfree(node);
 	return rv;
@@ -841,11 +887,11 @@ int xenbus_unmap_ring(struct xenbus_device *dev,
 		      grant_handle_t *handles, unsigned int nr_handles,
 		      unsigned long *vaddrs)
 {
-	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES];
+	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
 	int i;
 	int err;
 
-	if (nr_handles > XENBUS_MAX_RING_PAGES)
+	if (nr_handles > XENBUS_MAX_RING_GRANTS)
 		return -EINVAL;
 
 	for (i = 0; i < nr_handles; i++)
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3cbe0556de26..33a31cfef55d 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -802,7 +802,8 @@ static int __init xenbus_init(void)
 			goto out_error;
 		xen_store_gfn = (unsigned long)v;
 		xen_store_interface =
-			xen_remap(xen_store_gfn << PAGE_SHIFT, PAGE_SIZE);
+			xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
+				  XEN_PAGE_SIZE);
 		break;
 	default:
 		pr_warn("Xenstore state unknown\n");
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
index cff23872c5a9..5063c5e796b7 100644
--- a/drivers/xen/xlate_mmu.c
+++ b/drivers/xen/xlate_mmu.c
@@ -38,31 +38,28 @@
 #include <xen/interface/xen.h>
 #include <xen/interface/memory.h>
 
-/* map fgfn of domid to lpfn in the current domain */
-static int map_foreign_page(unsigned long lpfn, unsigned long fgfn,
-			    unsigned int domid)
-{
-	int rc;
-	struct xen_add_to_physmap_range xatp = {
-		.domid = DOMID_SELF,
-		.foreign_domid = domid,
-		.size = 1,
-		.space = XENMAPSPACE_gmfn_foreign,
-	};
-	xen_ulong_t idx = fgfn;
-	xen_pfn_t gpfn = lpfn;
-	int err = 0;
+typedef void (*xen_gfn_fn_t)(unsigned long gfn, void *data);
 
-	set_xen_guest_handle(xatp.idxs, &idx);
-	set_xen_guest_handle(xatp.gpfns, &gpfn);
-	set_xen_guest_handle(xatp.errs, &err);
+/* Break down the pages in 4KB chunk and call fn for each gfn */
+static void xen_for_each_gfn(struct page **pages, unsigned nr_gfn,
+			     xen_gfn_fn_t fn, void *data)
+{
+	unsigned long xen_pfn = 0;
+	struct page *page;
+	int i;
 
-	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
-	return rc < 0 ? rc : err;
+	for (i = 0; i < nr_gfn; i++) {
+		if ((i % XEN_PFN_PER_PAGE) == 0) {
+			page = pages[i / XEN_PFN_PER_PAGE];
+			xen_pfn = page_to_xen_pfn(page);
+		}
+		fn(pfn_to_gfn(xen_pfn++), data);
+	}
 }
 
 struct remap_data {
 	xen_pfn_t *fgfn; /* foreign domain's gfn */
+	int nr_fgfn; /* Number of foreign gfn left to map */
 	pgprot_t prot;
 	domid_t  domid;
 	struct vm_area_struct *vma;
@@ -71,24 +68,71 @@ struct remap_data {
 	struct xen_remap_gfn_info *info;
 	int *err_ptr;
 	int mapped;
+
+	/* Hypercall parameters */
+	int h_errs[XEN_PFN_PER_PAGE];
+	xen_ulong_t h_idxs[XEN_PFN_PER_PAGE];
+	xen_pfn_t h_gpfns[XEN_PFN_PER_PAGE];
+
+	int h_iter;	/* Iterator */
 };
 
+static void setup_hparams(unsigned long gfn, void *data)
+{
+	struct remap_data *info = data;
+
+	info->h_idxs[info->h_iter] = *info->fgfn;
+	info->h_gpfns[info->h_iter] = gfn;
+	info->h_errs[info->h_iter] = 0;
+
+	info->h_iter++;
+	info->fgfn++;
+}
+
 static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
 			void *data)
 {
 	struct remap_data *info = data;
 	struct page *page = info->pages[info->index++];
-	unsigned long pfn = page_to_pfn(page);
-	pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot));
-	int rc;
+	pte_t pte = pte_mkspecial(pfn_pte(page_to_pfn(page), info->prot));
+	int rc, nr_gfn;
+	uint32_t i;
+	struct xen_add_to_physmap_range xatp = {
+		.domid = DOMID_SELF,
+		.foreign_domid = info->domid,
+		.space = XENMAPSPACE_gmfn_foreign,
+	};
 
-	rc = map_foreign_page(pfn, *info->fgfn, info->domid);
-	*info->err_ptr++ = rc;
-	if (!rc) {
-		set_pte_at(info->vma->vm_mm, addr, ptep, pte);
-		info->mapped++;
+	nr_gfn = min_t(typeof(info->nr_fgfn), XEN_PFN_PER_PAGE, info->nr_fgfn);
+	info->nr_fgfn -= nr_gfn;
+
+	info->h_iter = 0;
+	xen_for_each_gfn(&page, nr_gfn, setup_hparams, info);
+	BUG_ON(info->h_iter != nr_gfn);
+
+	set_xen_guest_handle(xatp.idxs, info->h_idxs);
+	set_xen_guest_handle(xatp.gpfns, info->h_gpfns);
+	set_xen_guest_handle(xatp.errs, info->h_errs);
+	xatp.size = nr_gfn;
+
+	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
+
+	/* info->err_ptr expect to have one error status per Xen PFN */
+	for (i = 0; i < nr_gfn; i++) {
+		int err = (rc < 0) ? rc : info->h_errs[i];
+
+		*(info->err_ptr++) = err;
+		if (!err)
+			info->mapped++;
 	}
-	info->fgfn++;
+
+	/*
+	 * Note: The hypercall will return 0 in most of the case if even if
+	 * all the fgmfn are not mapped. We still have to update the pte
+	 * as the userspace may decide to continue.
+	 */
+	if (!rc)
+		set_pte_at(info->vma->vm_mm, addr, ptep, pte);
 
 	return 0;
 }
@@ -102,13 +146,14 @@ int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
 {
 	int err;
 	struct remap_data data;
-	unsigned long range = nr << PAGE_SHIFT;
+	unsigned long range = DIV_ROUND_UP(nr, XEN_PFN_PER_PAGE) << PAGE_SHIFT;
 
 	/* Kept here for the purpose of making sure code doesn't break
 	   x86 PVOPS */
 	BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
 
 	data.fgfn = gfn;
+	data.nr_fgfn = nr;
 	data.prot  = prot;
 	data.domid = domid;
 	data.vma   = vma;
@@ -123,21 +168,20 @@ int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
 }
 EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
 
-int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
-			      int nr, struct page **pages)
+static void unmap_gfn(unsigned long gfn, void *data)
 {
-	int i;
+	struct xen_remove_from_physmap xrp;
 
-	for (i = 0; i < nr; i++) {
-		struct xen_remove_from_physmap xrp;
-		unsigned long pfn;
+	xrp.domid = DOMID_SELF;
+	xrp.gpfn = gfn;
+	(void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
+}
 
-		pfn = page_to_pfn(pages[i]);
+int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
+			      int nr, struct page **pages)
+{
+	xen_for_each_gfn(pages, nr, unmap_gfn, NULL);
 
-		xrp.domid = DOMID_SELF;
-		xrp.gpfn = pfn;
-		(void)HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
-	}
 	return 0;
 }
 EXPORT_SYMBOL_GPL(xen_xlate_unmap_gfn_range);