Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

14 files changed, 674 insertions, 242 deletions

diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index 94d96809e686..a270004c9605 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -270,4 +270,10 @@ config XEN_EFI
 	def_bool y
 	depends on X86_64 && EFI
 
+config XEN_AUTO_XLATE
+	def_bool y
+	depends on ARM || ARM64 || XEN_PVHVM
+	help
+	  Support for auto-translated physmap guests.
+
 endmenu
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 2ccd3592d41f..40edd1cbb60d 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_XEN_ACPI_HOTPLUG_CPU)	+= xen-acpi-cpuhotplug.o
 obj-$(CONFIG_XEN_ACPI_PROCESSOR)	+= xen-acpi-processor.o
 obj-$(CONFIG_XEN_EFI)			+= efi.o
 obj-$(CONFIG_XEN_SCSI_BACKEND)		+= xen-scsiback.o
+obj-$(CONFIG_XEN_AUTO_XLATE)		+= xlate_mmu.o
 xen-evtchn-y				:= evtchn.o
 xen-gntdev-y				:= gntdev.o
 xen-gntalloc-y				:= gntalloc.o
diff --git a/drivers/xen/mcelog.c b/drivers/xen/mcelog.c
index 6ab6a79c38a5..a493c7315e94 100644
--- a/drivers/xen/mcelog.c
+++ b/drivers/xen/mcelog.c
@@ -393,14 +393,25 @@ static int bind_virq_for_mce(void)
 
 static int __init xen_late_init_mcelog(void)
 {
+	int ret;
+
 	/* Only DOM0 is responsible for MCE logging */
-	if (xen_initial_domain()) {
-		/* register character device /dev/mcelog for xen mcelog */
-		if (misc_register(&xen_mce_chrdev_device))
-			return -ENODEV;
-		return bind_virq_for_mce();
-	}
+	if (!xen_initial_domain())
+		return -ENODEV;
+
+	/* register character device /dev/mcelog for xen mcelog */
+	ret = misc_register(&xen_mce_chrdev_device);
+	if (ret)
+		return ret;
+
+	ret = bind_virq_for_mce();
+	if (ret)
+		goto deregister;
 
-	return -ENODEV;
+	return 0;
+
+deregister:
+	misc_deregister(&xen_mce_chrdev_device);
+	return ret;
 }
 device_initcall(xen_late_init_mcelog);
diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
index 95ee4302ffb8..7494dbeb4409 100644
--- a/drivers/xen/pci.c
+++ b/drivers/xen/pci.c
@@ -19,6 +19,7 @@
 
 #include <linux/pci.h>
 #include <linux/acpi.h>
+#include <linux/pci-acpi.h>
 #include <xen/xen.h>
 #include <xen/interface/physdev.h>
 #include <xen/interface/xen.h>
@@ -67,12 +68,22 @@ static int xen_add_device(struct device *dev)
 
 #ifdef CONFIG_ACPI
 		handle = ACPI_HANDLE(&pci_dev->dev);
-		if (!handle && pci_dev->bus->bridge)
-			handle = ACPI_HANDLE(pci_dev->bus->bridge);
 #ifdef CONFIG_PCI_IOV
 		if (!handle && pci_dev->is_virtfn)
 			handle = ACPI_HANDLE(physfn->bus->bridge);
 #endif
+		if (!handle) {
+			/*
+			 * This device was not listed in the ACPI name space at
+			 * all. Try to get acpi handle of parent pci bus.
+			 */
+			struct pci_bus *pbus;
+			for (pbus = pci_dev->bus; pbus; pbus = pbus->parent) {
+				handle = acpi_pci_get_bridge_handle(pbus);
+				if (handle)
+					break;
+			}
+		}
 		if (handle) {
 			acpi_status status;
 
diff --git a/drivers/xen/pcpu.c b/drivers/xen/pcpu.c
index 0aac403d53fd..49e88f2ce7a1 100644
--- a/drivers/xen/pcpu.c
+++ b/drivers/xen/pcpu.c
@@ -132,6 +132,33 @@ static ssize_t __ref store_online(struct device *dev,
 }
 static DEVICE_ATTR(online, S_IRUGO | S_IWUSR, show_online, store_online);
 
+static struct attribute *pcpu_dev_attrs[] = {
+	&dev_attr_online.attr,
+	NULL
+};
+
+static umode_t pcpu_dev_is_visible(struct kobject *kobj,
+				   struct attribute *attr, int idx)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	/*
+	 * Xen never offline cpu0 due to several restrictions
+	 * and assumptions. This basically doesn't add a sys control
+	 * to user, one cannot attempt to offline BSP.
+	 */
+	return dev->id ? attr->mode : 0;
+}
+
+static const struct attribute_group pcpu_dev_group = {
+	.attrs = pcpu_dev_attrs,
+	.is_visible = pcpu_dev_is_visible,
+};
+
+static const struct attribute_group *pcpu_dev_groups[] = {
+	&pcpu_dev_group,
+	NULL
+};
+
 static bool xen_pcpu_online(uint32_t flags)
 {
 	return !!(flags & XEN_PCPU_FLAGS_ONLINE);
@@ -181,9 +208,6 @@ static void unregister_and_remove_pcpu(struct pcpu *pcpu)
 		return;
 
 	dev = &pcpu->dev;
-	if (dev->id)
-		device_remove_file(dev, &dev_attr_online);
-
 	/* pcpu remove would be implicitly done */
 	device_unregister(dev);
 }
@@ -200,6 +224,7 @@ static int register_pcpu(struct pcpu *pcpu)
 	dev->bus = &xen_pcpu_subsys;
 	dev->id = pcpu->cpu_id;
 	dev->release = pcpu_release;
+	dev->groups = pcpu_dev_groups;
 
 	err = device_register(dev);
 	if (err) {
@@ -207,19 +232,6 @@ static int register_pcpu(struct pcpu *pcpu)
 		return err;
 	}
 
-	/*
-	 * Xen never offline cpu0 due to several restrictions
-	 * and assumptions. This basically doesn't add a sys control
-	 * to user, one cannot attempt to offline BSP.
-	 */
-	if (dev->id) {
-		err = device_create_file(dev, &dev_attr_online);
-		if (err) {
-			device_unregister(dev);
-			return err;
-		}
-	}
-
 	return 0;
 }
 
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index 59ac71c4a043..5a296161d843 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -159,6 +159,40 @@ static int traverse_pages(unsigned nelem, size_t size,
 	return ret;
 }
 
+/*
+ * Similar to traverse_pages, but use each page as a "block" of
+ * data to be processed as one unit.
+ */
+static int traverse_pages_block(unsigned nelem, size_t size,
+				struct list_head *pos,
+				int (*fn)(void *data, int nr, void *state),
+				void *state)
+{
+	void *pagedata;
+	unsigned pageidx;
+	int ret = 0;
+
+	BUG_ON(size > PAGE_SIZE);
+
+	pageidx = PAGE_SIZE;
+
+	while (nelem) {
+		int nr = (PAGE_SIZE/size);
+		struct page *page;
+		if (nr > nelem)
+			nr = nelem;
+		pos = pos->next;
+		page = list_entry(pos, struct page, lru);
+		pagedata = page_address(page);
+		ret = (*fn)(pagedata, nr, state);
+		if (ret)
+			break;
+		nelem -= nr;
+	}
+
+	return ret;
+}
+
 struct mmap_mfn_state {
 	unsigned long va;
 	struct vm_area_struct *vma;
@@ -274,39 +308,25 @@ struct mmap_batch_state {
 /* auto translated dom0 note: if domU being created is PV, then mfn is
  * mfn(addr on bus). If it's auto xlated, then mfn is pfn (input to HAP).
  */
-static int mmap_batch_fn(void *data, void *state)
+static int mmap_batch_fn(void *data, int nr, void *state)
 {
 	xen_pfn_t *mfnp = data;
 	struct mmap_batch_state *st = state;
 	struct vm_area_struct *vma = st->vma;
 	struct page **pages = vma->vm_private_data;
-	struct page *cur_page = NULL;
+	struct page **cur_pages = NULL;
 	int ret;
 
 	if (xen_feature(XENFEAT_auto_translated_physmap))
-		cur_page = pages[st->index++];
+		cur_pages = &pages[st->index];
 
-	ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
-					 st->vma->vm_page_prot, st->domain,
-					 &cur_page);
+	BUG_ON(nr < 0);
+	ret = xen_remap_domain_mfn_array(st->vma, st->va & PAGE_MASK, mfnp, nr,
+					 (int *)mfnp, st->vma->vm_page_prot,
+					 st->domain, cur_pages);
 
-	/* Store error code for second pass. */
-	if (st->version == 1) {
-		if (ret < 0) {
-			/*
-			 * V1 encodes the error codes in the 32bit top nibble of the
-			 * mfn (with its known limitations vis-a-vis 64 bit callers).
-			 */
-			*mfnp |= (ret == -ENOENT) ?
-						PRIVCMD_MMAPBATCH_PAGED_ERROR :
-						PRIVCMD_MMAPBATCH_MFN_ERROR;
-		}
-	} else { /* st->version == 2 */
-		*((int *) mfnp) = ret;
-	}
-
-	/* And see if it affects the global_error. */
-	if (ret < 0) {
+	/* Adjust the global_error? */
+	if (ret != nr) {
 		if (ret == -ENOENT)
 			st->global_error = -ENOENT;
 		else {
@@ -315,23 +335,35 @@ static int mmap_batch_fn(void *data, void *state)
 				st->global_error = 1;
 		}
 	}
-	st->va += PAGE_SIZE;
+	st->va += PAGE_SIZE * nr;
+	st->index += nr;
 
 	return 0;
 }
 
-static int mmap_return_errors(void *data, void *state)
+static int mmap_return_error(int err, struct mmap_batch_state *st)
 {
-	struct mmap_batch_state *st = state;
+	int ret;
 
 	if (st->version == 1) {
-		xen_pfn_t mfnp = *((xen_pfn_t *) data);
-		if (mfnp & PRIVCMD_MMAPBATCH_MFN_ERROR)
-			return __put_user(mfnp, st->user_mfn++);
-		else
+		if (err) {
+			xen_pfn_t mfn;
+
+			ret = get_user(mfn, st->user_mfn);
+			if (ret < 0)
+				return ret;
+			/*
+			 * V1 encodes the error codes in the 32bit top
+			 * nibble of the mfn (with its known
+			 * limitations vis-a-vis 64 bit callers).
+			 */
+			mfn |= (err == -ENOENT) ?
+				PRIVCMD_MMAPBATCH_PAGED_ERROR :
+				PRIVCMD_MMAPBATCH_MFN_ERROR;
+			return __put_user(mfn, st->user_mfn++);
+		} else
 			st->user_mfn++;
 	} else { /* st->version == 2 */
-		int err = *((int *) data);
 		if (err)
 			return __put_user(err, st->user_err++);
 		else
@@ -341,6 +373,21 @@ static int mmap_return_errors(void *data, void *state)
 	return 0;
 }
 
+static int mmap_return_errors(void *data, int nr, void *state)
+{
+	struct mmap_batch_state *st = state;
+	int *errs = data;
+	int i;
+	int ret;
+
+	for (i = 0; i < nr; i++) {
+		ret = mmap_return_error(errs[i], st);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
 /* Allocate pfns that are then mapped with gmfns from foreign domid. Update
  * the vma with the page info to use later.
  * Returns: 0 if success, otherwise -errno
@@ -472,8 +519,8 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 	state.version       = version;
 
 	/* mmap_batch_fn guarantees ret == 0 */
-	BUG_ON(traverse_pages(m.num, sizeof(xen_pfn_t),
-			     &pagelist, mmap_batch_fn, &state));
+	BUG_ON(traverse_pages_block(m.num, sizeof(xen_pfn_t),
+				    &pagelist, mmap_batch_fn, &state));
 
 	up_write(&mm->mmap_sem);
 
@@ -481,8 +528,8 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 		/* Write back errors in second pass. */
 		state.user_mfn = (xen_pfn_t *)m.arr;
 		state.user_err = m.err;
-		ret = traverse_pages(m.num, sizeof(xen_pfn_t),
-							 &pagelist, mmap_return_errors, &state);
+		ret = traverse_pages_block(m.num, sizeof(xen_pfn_t),
+					   &pagelist, mmap_return_errors, &state);
 	} else
 		ret = 0;
 
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index 8a65423bc696..c4211a31612d 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -397,13 +397,15 @@ static int __init xen_tmem_init(void)
 #ifdef CONFIG_CLEANCACHE
 	BUG_ON(sizeof(struct cleancache_filekey) != sizeof(struct tmem_oid));
 	if (tmem_enabled && cleancache) {
-		char *s = "";
-		struct cleancache_ops *old_ops =
-			cleancache_register_ops(&tmem_cleancache_ops);
-		if (old_ops)
-			s = " (WARNING: cleancache_ops overridden)";
-		pr_info("cleancache enabled, RAM provided by Xen Transcendent Memory%s\n",
-			s);
+		int err;
+
+		err = cleancache_register_ops(&tmem_cleancache_ops);
+		if (err)
+			pr_warn("xen-tmem: failed to enable cleancache: %d\n",
+				err);
+		else
+			pr_info("cleancache enabled, RAM provided by "
+				"Xen Transcendent Memory\n");
 	}
 #endif
 #ifdef CONFIG_XEN_SELFBALLOONING
diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c
index e555845d61fa..39e7ef8d3957 100644
--- a/drivers/xen/xen-balloon.c
+++ b/drivers/xen/xen-balloon.c
@@ -193,13 +193,18 @@ static DEVICE_ATTR(target, S_IRUGO | S_IWUSR,
 		   show_target, store_target);
 
 
-static struct device_attribute *balloon_attrs[] = {
-	&dev_attr_target_kb,
-	&dev_attr_target,
-	&dev_attr_schedule_delay.attr,
-	&dev_attr_max_schedule_delay.attr,
-	&dev_attr_retry_count.attr,
-	&dev_attr_max_retry_count.attr
+static struct attribute *balloon_attrs[] = {
+	&dev_attr_target_kb.attr,
+	&dev_attr_target.attr,
+	&dev_attr_schedule_delay.attr.attr,
+	&dev_attr_max_schedule_delay.attr.attr,
+	&dev_attr_retry_count.attr.attr,
+	&dev_attr_max_retry_count.attr.attr,
+	NULL
+};
+
+static const struct attribute_group balloon_group = {
+	.attrs = balloon_attrs
 };
 
 static struct attribute *balloon_info_attrs[] = {
@@ -214,6 +219,12 @@ static const struct attribute_group balloon_info_group = {
 	.attrs = balloon_info_attrs
 };
 
+static const struct attribute_group *balloon_groups[] = {
+	&balloon_group,
+	&balloon_info_group,
+	NULL
+};
+
 static struct bus_type balloon_subsys = {
 	.name = BALLOON_CLASS_NAME,
 	.dev_name = BALLOON_CLASS_NAME,
@@ -221,7 +232,7 @@ static struct bus_type balloon_subsys = {
 
 static int register_balloon(struct device *dev)
 {
-	int i, error;
+	int error;
 
 	error = subsys_system_register(&balloon_subsys, NULL);
 	if (error)
@@ -229,6 +240,7 @@ static int register_balloon(struct device *dev)
 
 	dev->id = 0;
 	dev->bus = &balloon_subsys;
+	dev->groups = balloon_groups;
 
 	error = device_register(dev);
 	if (error) {
@@ -236,24 +248,7 @@ static int register_balloon(struct device *dev)
 		return error;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(balloon_attrs); i++) {
-		error = device_create_file(dev, balloon_attrs[i]);
-		if (error)
-			goto fail;
-	}
-
-	error = sysfs_create_group(&dev->kobj, &balloon_info_group);
-	if (error)
-		goto fail;
-
 	return 0;
-
- fail:
-	while (--i >= 0)
-		device_remove_file(dev, balloon_attrs[i]);
-	device_unregister(dev);
-	bus_unregister(&balloon_subsys);
-	return error;
 }
 
 MODULE_LICENSE("GPL");
diff --git a/drivers/xen/xen-pciback/conf_space_header.c b/drivers/xen/xen-pciback/conf_space_header.c
index 2d7369391472..c2260a0456c9 100644
--- a/drivers/xen/xen-pciback/conf_space_header.c
+++ b/drivers/xen/xen-pciback/conf_space_header.c
@@ -88,9 +88,15 @@ static int command_write(struct pci_dev *dev, int offset, u16 value, void *data)
 			printk(KERN_DEBUG DRV_NAME ": %s: set bus master\n",
 			       pci_name(dev));
 		pci_set_master(dev);
+	} else if (dev->is_busmaster && !is_master_cmd(value)) {
+		if (unlikely(verbose_request))
+			printk(KERN_DEBUG DRV_NAME ": %s: clear bus master\n",
+			       pci_name(dev));
+		pci_clear_master(dev);
 	}
 
-	if (value & PCI_COMMAND_INVALIDATE) {
+	if (!(cmd->val & PCI_COMMAND_INVALIDATE) &&
+	    (value & PCI_COMMAND_INVALIDATE)) {
 		if (unlikely(verbose_request))
 			printk(KERN_DEBUG
 			       DRV_NAME ": %s: enable memory-write-invalidate\n",
@@ -101,6 +107,13 @@ static int command_write(struct pci_dev *dev, int offset, u16 value, void *data)
 				pci_name(dev), err);
 			value &= ~PCI_COMMAND_INVALIDATE;
 		}
+	} else if ((cmd->val & PCI_COMMAND_INVALIDATE) &&
+		   !(value & PCI_COMMAND_INVALIDATE)) {
+		if (unlikely(verbose_request))
+			printk(KERN_DEBUG
+			       DRV_NAME ": %s: disable memory-write-invalidate\n",
+			       pci_name(dev));
+		pci_clear_mwi(dev);
 	}
 
 	cmd->val = value;
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index cc3cbb4435f8..258b7c325649 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -118,7 +118,7 @@ static void pcistub_device_release(struct kref *kref)
 		int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 						&ppdev);
 
-		if (err)
+		if (err && err != -ENOSYS)
 			dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 				 err);
 	}
@@ -402,7 +402,7 @@ static int pcistub_init_device(struct pci_dev *dev)
 		};
 
 		err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
-		if (err)
+		if (err && err != -ENOSYS)
 			dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 				err);
 	}
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index fe17c80ff4b7..98bc345f296e 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -113,7 +113,7 @@ static int xen_pcibk_do_attach(struct xen_pcibk_device *pdev, int gnt_ref,
 		"Attaching to frontend resources - gnt_ref=%d evtchn=%d\n",
 		gnt_ref, remote_evtchn);
 
-	err = xenbus_map_ring_valloc(pdev->xdev, gnt_ref, &vaddr);
+	err = xenbus_map_ring_valloc(pdev->xdev, &gnt_ref, 1, &vaddr);
 	if (err < 0) {
 		xenbus_dev_fatal(pdev->xdev, err,
 				"Error mapping other domain page in ours.");
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index 42bd55a6c237..07ef38325223 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -31,6 +31,8 @@
  * IN THE SOFTWARE.
  */
 
+#define pr_fmt(fmt) "xen-pvscsi: " fmt
+
 #include <stdarg.h>
 
 #include <linux/module.h>
@@ -69,9 +71,6 @@
 #include <xen/interface/grant_table.h>
 #include <xen/interface/io/vscsiif.h>
 
-#define DPRINTK(_f, _a...)			\
-	pr_debug("(file=%s, line=%d) " _f, __FILE__ , __LINE__ , ## _a)
-
 #define VSCSI_VERSION	"v0.1"
 #define VSCSI_NAMELEN	32
 
@@ -271,7 +270,7 @@ static void scsiback_print_status(char *sense_buffer, int errors,
 {
 	struct scsiback_tpg *tpg = pending_req->v2p->tpg;
 
-	pr_err("xen-pvscsi[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n",
+	pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n",
 	       tpg->tport->tport_name, pending_req->v2p->lun,
 	       pending_req->cmnd[0], status_byte(errors), msg_byte(errors),
 	       host_byte(errors), driver_byte(errors));
@@ -427,7 +426,7 @@ static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map,
 	BUG_ON(err);
 	for (i = 0; i < cnt; i++) {
 		if (unlikely(map[i].status != GNTST_okay)) {
-			pr_err("xen-pvscsi: invalid buffer -- could not remap it\n");
+			pr_err("invalid buffer -- could not remap it\n");
 			map[i].handle = SCSIBACK_INVALID_HANDLE;
 			err = -ENOMEM;
 		} else {
@@ -449,7 +448,7 @@ static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req,
 	for (i = 0; i < cnt; i++) {
 		if (get_free_page(pg + mapcount)) {
 			put_free_pages(pg, mapcount);
-			pr_err("xen-pvscsi: no grant page\n");
+			pr_err("no grant page\n");
 			return -ENOMEM;
 		}
 		gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]),
@@ -492,7 +491,7 @@ static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
 		return 0;
 
 	if (nr_segments > VSCSIIF_SG_TABLESIZE) {
-		DPRINTK("xen-pvscsi: invalid parameter nr_seg = %d\n",
+		pr_debug("invalid parameter nr_seg = %d\n",
 			ring_req->nr_segments);
 		return -EINVAL;
 	}
@@ -516,13 +515,12 @@ static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req,
 			nr_segments += n_segs;
 		}
 		if (nr_segments > SG_ALL) {
-			DPRINTK("xen-pvscsi: invalid nr_seg = %d\n",
-				nr_segments);
+			pr_debug("invalid nr_seg = %d\n", nr_segments);
 			return -EINVAL;
 		}
 	}
 
-	/* free of (sgl) in fast_flush_area()*/
+	/* free of (sgl) in fast_flush_area() */
 	pending_req->sgl = kmalloc_array(nr_segments,
 					sizeof(struct scatterlist), GFP_KERNEL);
 	if (!pending_req->sgl)
@@ -679,7 +677,8 @@ static int prepare_pending_reqs(struct vscsibk_info *info,
 	v2p = scsiback_do_translation(info, &vir);
 	if (!v2p) {
 		pending_req->v2p = NULL;
-		DPRINTK("xen-pvscsi: doesn't exist.\n");
+		pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n",
+			vir.chn, vir.tgt, vir.lun);
 		return -ENODEV;
 	}
 	pending_req->v2p = v2p;
@@ -690,14 +689,14 @@ static int prepare_pending_reqs(struct vscsibk_info *info,
 		(pending_req->sc_data_direction != DMA_TO_DEVICE) &&
 		(pending_req->sc_data_direction != DMA_FROM_DEVICE) &&
 		(pending_req->sc_data_direction != DMA_NONE)) {
-		DPRINTK("xen-pvscsi: invalid parameter data_dir = %d\n",
+		pr_debug("invalid parameter data_dir = %d\n",
 			pending_req->sc_data_direction);
 		return -EINVAL;
 	}
 
 	pending_req->cmd_len = ring_req->cmd_len;
 	if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) {
-		DPRINTK("xen-pvscsi: invalid parameter cmd_len = %d\n",
+		pr_debug("invalid parameter cmd_len = %d\n",
 			pending_req->cmd_len);
 		return -EINVAL;
 	}
@@ -721,7 +720,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
 
 	if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) {
 		rc = ring->rsp_prod_pvt;
-		pr_warn("xen-pvscsi: Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
+		pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n",
 			   info->domid, rp, rc, rp - rc);
 		info->ring_error = 1;
 		return 0;
@@ -772,7 +771,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
 			scsiback_device_action(pending_req, TMR_LUN_RESET, 0);
 			break;
 		default:
-			pr_err_ratelimited("xen-pvscsi: invalid request\n");
+			pr_err_ratelimited("invalid request\n");
 			scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24,
 						    0, pending_req);
 			kmem_cache_free(scsiback_cachep, pending_req);
@@ -810,7 +809,7 @@ static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
 	if (info->irq)
 		return -1;
 
-	err = xenbus_map_ring_valloc(info->dev, ring_ref, &area);
+	err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area);
 	if (err)
 		return err;
 
@@ -874,14 +873,13 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info,
 
 	lunp = strrchr(phy, ':');
 	if (!lunp) {
-		pr_err("xen-pvscsi: illegal format of physical device %s\n",
-			phy);
+		pr_err("illegal format of physical device %s\n", phy);
 		return -EINVAL;
 	}
 	*lunp = 0;
 	lunp++;
 	if (kstrtouint(lunp, 10, &lun) || lun >= TRANSPORT_MAX_LUNS_PER_TPG) {
-		pr_err("xen-pvscsi: lun number not valid: %s\n", lunp);
+		pr_err("lun number not valid: %s\n", lunp);
 		return -EINVAL;
 	}
 
@@ -909,7 +907,7 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info,
 	mutex_unlock(&scsiback_mutex);
 
 	if (!tpg) {
-		pr_err("xen-pvscsi: %s:%d %s\n", phy, lun, error);
+		pr_err("%s:%d %s\n", phy, lun, error);
 		return -ENODEV;
 	}
 
@@ -926,7 +924,7 @@ static int scsiback_add_translation_entry(struct vscsibk_info *info,
 		if ((entry->v.chn == v->chn) &&
 		    (entry->v.tgt == v->tgt) &&
 		    (entry->v.lun == v->lun)) {
-			pr_warn("xen-pvscsi: Virtual ID is already used. Assignment was not performed.\n");
+			pr_warn("Virtual ID is already used. Assignment was not performed.\n");
 			err = -EEXIST;
 			goto out;
 		}
@@ -992,15 +990,15 @@ found:
 }
 
 static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state,
-				char *phy, struct ids_tuple *vir)
+				char *phy, struct ids_tuple *vir, int try)
 {
 	if (!scsiback_add_translation_entry(info, phy, vir)) {
 		if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
 				  "%d", XenbusStateInitialised)) {
-			pr_err("xen-pvscsi: xenbus_printf error %s\n", state);
+			pr_err("xenbus_printf error %s\n", state);
 			scsiback_del_translation_entry(info, vir);
 		}
-	} else {
+	} else if (!try) {
 		xenbus_printf(XBT_NIL, info->dev->nodename, state,
 			      "%d", XenbusStateClosed);
 	}
@@ -1012,7 +1010,7 @@ static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state,
 	if (!scsiback_del_translation_entry(info, vir)) {
 		if (xenbus_printf(XBT_NIL, info->dev->nodename, state,
 				  "%d", XenbusStateClosed))
-			pr_err("xen-pvscsi: xenbus_printf error %s\n", state);
+			pr_err("xenbus_printf error %s\n", state);
 	}
 }
 
@@ -1060,10 +1058,19 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
 
 	switch (op) {
 	case VSCSIBACK_OP_ADD_OR_DEL_LUN:
-		if (device_state == XenbusStateInitialising)
-			scsiback_do_add_lun(info, state, phy, &vir);
-		if (device_state == XenbusStateClosing)
+		switch (device_state) {
+		case XenbusStateInitialising:
+			scsiback_do_add_lun(info, state, phy, &vir, 0);
+			break;
+		case XenbusStateConnected:
+			scsiback_do_add_lun(info, state, phy, &vir, 1);
+			break;
+		case XenbusStateClosing:
 			scsiback_do_del_lun(info, state, &vir);
+			break;
+		default:
+			break;
+		}
 		break;
 
 	case VSCSIBACK_OP_UPDATEDEV_STATE:
@@ -1071,15 +1078,14 @@ static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op,
 			/* modify vscsi-devs/dev-x/state */
 			if (xenbus_printf(XBT_NIL, dev->nodename, state,
 					  "%d", XenbusStateConnected)) {
-				pr_err("xen-pvscsi: xenbus_printf error %s\n",
-				       str);
+				pr_err("xenbus_printf error %s\n", str);
 				scsiback_del_translation_entry(info, &vir);
 				xenbus_printf(XBT_NIL, dev->nodename, state,
 					      "%d", XenbusStateClosed);
 			}
 		}
 		break;
-	/*When it is necessary, processing is added here.*/
+	/* When it is necessary, processing is added here. */
 	default:
 		break;
 	}
@@ -1196,7 +1202,7 @@ static int scsiback_probe(struct xenbus_device *dev,
 	struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info),
 					    GFP_KERNEL);
 
-	DPRINTK("%p %d\n", dev, dev->otherend_id);
+	pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id);
 
 	if (!info) {
 		xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure");
@@ -1227,7 +1233,7 @@ static int scsiback_probe(struct xenbus_device *dev,
 	return 0;
 
 fail:
-	pr_warn("xen-pvscsi: %s failed\n", __func__);
+	pr_warn("%s failed\n", __func__);
 	scsiback_remove(dev);
 
 	return err;
@@ -1432,7 +1438,7 @@ check_len:
 	}
 	snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]);
 
-	pr_debug("xen-pvscsi: Allocated emulated Target %s Address: %s\n",
+	pr_debug("Allocated emulated Target %s Address: %s\n",
 		 scsiback_dump_proto_id(tport), name);
 
 	return &tport->tport_wwn;
@@ -1443,7 +1449,7 @@ static void scsiback_drop_tport(struct se_wwn *wwn)
 	struct scsiback_tport *tport = container_of(wwn,
 				struct scsiback_tport, tport_wwn);
 
-	pr_debug("xen-pvscsi: Deallocating emulated Target %s Address: %s\n",
+	pr_debug("Deallocating emulated Target %s Address: %s\n",
 		 scsiback_dump_proto_id(tport), tport->tport_name);
 
 	kfree(tport);
@@ -1470,8 +1476,8 @@ static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg)
 static int scsiback_check_stop_free(struct se_cmd *se_cmd)
 {
 	/*
-	 * Do not release struct se_cmd's containing a valid TMR
-	 * pointer.  These will be released directly in scsiback_device_action()
+	 * Do not release struct se_cmd's containing a valid TMR pointer.
+	 * These will be released directly in scsiback_device_action()
 	 * with transport_generic_free_cmd().
 	 */
 	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
@@ -1637,7 +1643,7 @@ static int scsiback_make_nexus(struct scsiback_tpg *tpg,
 		return -ENOMEM;
 	}
 	/*
-	 *  Initialize the struct se_session pointer
+	 * Initialize the struct se_session pointer
 	 */
 	tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL);
 	if (IS_ERR(tv_nexus->tvn_se_sess)) {
@@ -1705,7 +1711,7 @@ static int scsiback_drop_nexus(struct scsiback_tpg *tpg)
 		return -EBUSY;
 	}
 
-	pr_debug("xen-pvscsi: Removing I_T Nexus to emulated %s Initiator Port: %s\n",
+	pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n",
 		scsiback_dump_proto_id(tpg->tport),
 		tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
 
@@ -1751,7 +1757,7 @@ static ssize_t scsiback_tpg_store_nexus(struct se_portal_group *se_tpg,
 	unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr;
 	int ret;
 	/*
-	 * Shutdown the active I_T nexus if 'NULL' is passed..
+	 * Shutdown the active I_T nexus if 'NULL' is passed.
 	 */
 	if (!strncmp(page, "NULL", 4)) {
 		ret = scsiback_drop_nexus(tpg);
@@ -1922,7 +1928,7 @@ static void scsiback_drop_tpg(struct se_portal_group *se_tpg)
 	 */
 	scsiback_drop_nexus(tpg);
 	/*
-	 * Deregister the se_tpg from TCM..
+	 * Deregister the se_tpg from TCM.
 	 */
 	core_tpg_deregister(se_tpg);
 	kfree(tpg);
@@ -1992,7 +1998,7 @@ static int scsiback_register_configfs(void)
 	struct target_fabric_configfs *fabric;
 	int ret;
 
-	pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n",
+	pr_debug("fabric module %s on %s/%s on "UTS_RELEASE"\n",
 		 VSCSI_VERSION, utsname()->sysname, utsname()->machine);
 	/*
 	 * Register the top level struct config_item_type with TCM core
@@ -2029,7 +2035,7 @@ static int scsiback_register_configfs(void)
 	 * Setup our local pointer to *fabric
 	 */
 	scsiback_fabric_configfs = fabric;
-	pr_debug("xen-pvscsi: Set fabric -> scsiback_fabric_configfs\n");
+	pr_debug("Set fabric -> scsiback_fabric_configfs\n");
 	return 0;
 };
 
@@ -2040,7 +2046,7 @@ static void scsiback_deregister_configfs(void)
 
 	target_fabric_configfs_deregister(scsiback_fabric_configfs);
 	scsiback_fabric_configfs = NULL;
-	pr_debug("xen-pvscsi: Cleared scsiback_fabric_configfs\n");
+	pr_debug("Cleared scsiback_fabric_configfs\n");
 };
 
 static const struct xenbus_device_id scsiback_ids[] = {
@@ -2091,7 +2097,7 @@ out_unregister_xenbus:
 	xenbus_unregister_driver(&scsiback_driver);
 out_cache_destroy:
 	kmem_cache_destroy(scsiback_cachep);
-	pr_err("xen-pvscsi: %s: error %d\n", __func__, ret);
+	pr_err("%s: error %d\n", __func__, ret);
 	return ret;
 }
 
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index ca744102b666..96b2011d25f3 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -52,17 +52,25 @@
 struct xenbus_map_node {
 	struct list_head next;
 	union {
-		struct vm_struct *area; /* PV */
-		struct page *page;     /* HVM */
+		struct {
+			struct vm_struct *area;
+		} pv;
+		struct {
+			struct page *pages[XENBUS_MAX_RING_PAGES];
+			void *addr;
+		} hvm;
 	};
-	grant_handle_t handle;
+	grant_handle_t handles[XENBUS_MAX_RING_PAGES];
+	unsigned int   nr_handles;
 };
 
 static DEFINE_SPINLOCK(xenbus_valloc_lock);
 static LIST_HEAD(xenbus_valloc_pages);
 
 struct xenbus_ring_ops {
-	int (*map)(struct xenbus_device *dev, int gnt, void **vaddr);
+	int (*map)(struct xenbus_device *dev,
+		   grant_ref_t *gnt_refs, unsigned int nr_grefs,
+		   void **vaddr);
 	int (*unmap)(struct xenbus_device *dev, void *vaddr);
 };
 
@@ -355,17 +363,39 @@ static void xenbus_switch_fatal(struct xenbus_device *dev, int depth, int err,
 /**
  * xenbus_grant_ring
  * @dev: xenbus device
- * @ring_mfn: mfn of ring to grant
-
- * Grant access to the given @ring_mfn to the peer of the given device.  Return
- * a grant reference on success, or -errno on error. On error, the device will
- * switch to XenbusStateClosing, and the error will be saved in the store.
+ * @vaddr: starting virtual address of the ring
+ * @nr_pages: number of pages to be granted
+ * @grefs: grant reference array to be filled in
+ *
+ * Grant access to the given @vaddr to the peer of the given device.
+ * Then fill in @grefs with grant references.  Return 0 on success, or
+ * -errno on error.  On error, the device will switch to
+ * XenbusStateClosing, and the error will be saved in the store.
  */
-int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn)
+int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
+		      unsigned int nr_pages, grant_ref_t *grefs)
 {
-	int err = gnttab_grant_foreign_access(dev->otherend_id, ring_mfn, 0);
-	if (err < 0)
-		xenbus_dev_fatal(dev, err, "granting access to ring page");
+	int err;
+	int i, j;
+
+	for (i = 0; i < nr_pages; i++) {
+		unsigned long addr = (unsigned long)vaddr +
+			(PAGE_SIZE * i);
+		err = gnttab_grant_foreign_access(dev->otherend_id,
+						  virt_to_mfn(addr), 0);
+		if (err < 0) {
+			xenbus_dev_fatal(dev, err,
+					 "granting access to ring page");
+			goto fail;
+		}
+		grefs[i] = err;
+	}
+
+	return 0;
+
+fail:
+	for (j = 0; j < i; j++)
+		gnttab_end_foreign_access_ref(grefs[j], 0);
 	return err;
 }
 EXPORT_SYMBOL_GPL(xenbus_grant_ring);
@@ -419,62 +449,130 @@ EXPORT_SYMBOL_GPL(xenbus_free_evtchn);
 /**
  * xenbus_map_ring_valloc
  * @dev: xenbus device
- * @gnt_ref: grant reference
+ * @gnt_refs: grant reference array
+ * @nr_grefs: number of grant references
  * @vaddr: pointer to address to be filled out by mapping
  *
- * Based on Rusty Russell's skeleton driver's map_page.
- * Map a page of memory into this domain from another domain's grant table.
- * xenbus_map_ring_valloc allocates a page of virtual address space, maps the
- * page to that address, and sets *vaddr to that address.
- * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h)
- * or -ENOMEM on error. If an error is returned, device will switch to
+ * Map @nr_grefs pages of memory into this domain from another
+ * domain's grant table.  xenbus_map_ring_valloc allocates @nr_grefs
+ * pages of virtual address space, maps the pages to that address, and
+ * sets *vaddr to that address.  Returns 0 on success, and GNTST_*
+ * (see xen/include/interface/grant_table.h) or -ENOMEM / -EINVAL on
+ * error. If an error is returned, device will switch to
  * XenbusStateClosing and the error message will be saved in XenStore.
  */
-int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
+int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
+			   unsigned int nr_grefs, void **vaddr)
 {
-	return ring_ops->map(dev, gnt_ref, vaddr);
+	return ring_ops->map(dev, gnt_refs, nr_grefs, vaddr);
 }
 EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
 
+/* N.B. sizeof(phys_addr_t) doesn't always equal to sizeof(unsigned
+ * long), e.g. 32-on-64.  Caller is responsible for preparing the
+ * right array to feed into this function */
+static int __xenbus_map_ring(struct xenbus_device *dev,
+			     grant_ref_t *gnt_refs,
+			     unsigned int nr_grefs,
+			     grant_handle_t *handles,
+			     phys_addr_t *addrs,
+			     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];
+	int i, j;
+	int err = GNTST_okay;
+
+	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
+
+	for (i = 0; i < nr_grefs; i++) {
+		memset(&map[i], 0, sizeof(map[i]));
+		gnttab_set_map_op(&map[i], addrs[i], flags, gnt_refs[i],
+				  dev->otherend_id);
+		handles[i] = INVALID_GRANT_HANDLE;
+	}
+
+	gnttab_batch_map(map, i);
+
+	for (i = 0; i < nr_grefs; i++) {
+		if (map[i].status != GNTST_okay) {
+			err = map[i].status;
+			xenbus_dev_fatal(dev, map[i].status,
+					 "mapping in shared page %d from domain %d",
+					 gnt_refs[i], dev->otherend_id);
+			goto fail;
+		} else
+			handles[i] = map[i].handle;
+	}
+
+	return GNTST_okay;
+
+ fail:
+	for (i = j = 0; i < nr_grefs; i++) {
+		if (handles[i] != INVALID_GRANT_HANDLE) {
+			memset(&unmap[j], 0, sizeof(unmap[j]));
+			gnttab_set_unmap_op(&unmap[j], (phys_addr_t)addrs[i],
+					    GNTMAP_host_map, handles[i]);
+			j++;
+		}
+	}
+
+	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, j))
+		BUG();
+
+	*leaked = false;
+	for (i = 0; i < j; i++) {
+		if (unmap[i].status != GNTST_okay) {
+			*leaked = true;
+			break;
+		}
+	}
+
+	return err;
+}
+
 static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
-				     int gnt_ref, void **vaddr)
+				     grant_ref_t *gnt_refs,
+				     unsigned int nr_grefs,
+				     void **vaddr)
 {
-	struct gnttab_map_grant_ref op = {
-		.flags = GNTMAP_host_map | GNTMAP_contains_pte,
-		.ref   = gnt_ref,
-		.dom   = dev->otherend_id,
-	};
 	struct xenbus_map_node *node;
 	struct vm_struct *area;
-	pte_t *pte;
+	pte_t *ptes[XENBUS_MAX_RING_PAGES];
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
+	int err = GNTST_okay;
+	int i;
+	bool leaked;
 
 	*vaddr = NULL;
 
+	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
+
 	node = kzalloc(sizeof(*node), GFP_KERNEL);
 	if (!node)
 		return -ENOMEM;
 
-	area = alloc_vm_area(PAGE_SIZE, &pte);
+	area = alloc_vm_area(PAGE_SIZE * nr_grefs, ptes);
 	if (!area) {
 		kfree(node);
 		return -ENOMEM;
 	}
 
-	op.host_addr = arbitrary_virt_to_machine(pte).maddr;
+	for (i = 0; i < nr_grefs; i++)
+		phys_addrs[i] = arbitrary_virt_to_machine(ptes[i]).maddr;
 
-	gnttab_batch_map(&op, 1);
-
-	if (op.status != GNTST_okay) {
-		free_vm_area(area);
-		kfree(node);
-		xenbus_dev_fatal(dev, op.status,
-				 "mapping in shared page %d from domain %d",
-				 gnt_ref, dev->otherend_id);
-		return op.status;
-	}
+	err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
+				phys_addrs,
+				GNTMAP_host_map | GNTMAP_contains_pte,
+				&leaked);
+	if (err)
+		goto failed;
 
-	node->handle = op.handle;
-	node->area = area;
+	node->nr_handles = nr_grefs;
+	node->pv.area = area;
 
 	spin_lock(&xenbus_valloc_lock);
 	list_add(&node->next, &xenbus_valloc_pages);
@@ -482,14 +580,33 @@ static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
 
 	*vaddr = area->addr;
 	return 0;
+
+failed:
+	if (!leaked)
+		free_vm_area(area);
+	else
+		pr_alert("leaking VM area %p size %u page(s)", area, nr_grefs);
+
+	kfree(node);
+	return err;
 }
 
 static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
-				      int gnt_ref, void **vaddr)
+				      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];
+
+	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
 
 	*vaddr = NULL;
 
@@ -497,15 +614,32 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 	if (!node)
 		return -ENOMEM;
 
-	err = alloc_xenballooned_pages(1, &node->page, false /* lowmem */);
+	err = alloc_xenballooned_pages(nr_grefs, node->hvm.pages,
+				       false /* lowmem */);
 	if (err)
 		goto out_err;
 
-	addr = pfn_to_kaddr(page_to_pfn(node->page));
+	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);
+	}
+
+	err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles,
+				phys_addrs, GNTMAP_host_map, &leaked);
+	node->nr_handles = nr_grefs;
 
-	err = xenbus_map_ring(dev, gnt_ref, &node->handle, addr);
 	if (err)
-		goto out_err_free_ballooned_pages;
+		goto out_free_ballooned_pages;
+
+	addr = vmap(node->hvm.pages, nr_grefs, VM_MAP | VM_IOREMAP,
+		    PAGE_KERNEL);
+	if (!addr) {
+		err = -ENOMEM;
+		goto out_xenbus_unmap_ring;
+	}
+
+	node->hvm.addr = addr;
 
 	spin_lock(&xenbus_valloc_lock);
 	list_add(&node->next, &xenbus_valloc_pages);
@@ -514,8 +648,16 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 	*vaddr = addr;
 	return 0;
 
- out_err_free_ballooned_pages:
-	free_xenballooned_pages(1, &node->page);
+ out_xenbus_unmap_ring:
+	if (!leaked)
+		xenbus_unmap_ring(dev, node->handles, node->nr_handles,
+				  addrs);
+	else
+		pr_alert("leaking %p size %u page(s)",
+			 addr, nr_grefs);
+ out_free_ballooned_pages:
+	if (!leaked)
+		free_xenballooned_pages(nr_grefs, node->hvm.pages);
  out_err:
 	kfree(node);
 	return err;
@@ -525,35 +667,37 @@ static int xenbus_map_ring_valloc_hvm(struct xenbus_device *dev,
 /**
  * xenbus_map_ring
  * @dev: xenbus device
- * @gnt_ref: grant reference
- * @handle: pointer to grant handle to be filled
- * @vaddr: address to be mapped to
+ * @gnt_refs: grant reference array
+ * @nr_grefs: number of grant reference
+ * @handles: pointer to grant handle to be filled
+ * @vaddrs: addresses to be mapped to
+ * @leaked: fail to clean up a failed map, caller should not free vaddr
  *
- * Map a page of memory into this domain from another domain's grant table.
+ * Map pages of memory into this domain from another domain's grant table.
  * xenbus_map_ring does not allocate the virtual address space (you must do
- * this yourself!). It only maps in the page to the specified address.
+ * this yourself!). It only maps in the pages to the specified address.
  * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h)
- * or -ENOMEM on error. If an error is returned, device will switch to
- * XenbusStateClosing and the error message will be saved in XenStore.
+ * or -ENOMEM / -EINVAL on error. If an error is returned, device will switch to
+ * XenbusStateClosing and the first error message will be saved in XenStore.
+ * Further more if we fail to map the ring, caller should check @leaked.
+ * If @leaked is not zero it means xenbus_map_ring fails to clean up, caller
+ * should not free the address space of @vaddr.
  */
-int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
-		    grant_handle_t *handle, void *vaddr)
+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)
 {
-	struct gnttab_map_grant_ref op;
-
-	gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref,
-			  dev->otherend_id);
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
+	int i;
 
-	gnttab_batch_map(&op, 1);
+	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
 
-	if (op.status != GNTST_okay) {
-		xenbus_dev_fatal(dev, op.status,
-				 "mapping in shared page %d from domain %d",
-				 gnt_ref, dev->otherend_id);
-	} else
-		*handle = op.handle;
+	for (i = 0; i < nr_grefs; i++)
+		phys_addrs[i] = (unsigned long)vaddrs[i];
 
-	return op.status;
+	return __xenbus_map_ring(dev, gnt_refs, nr_grefs, handles,
+				 phys_addrs, GNTMAP_host_map, leaked);
 }
 EXPORT_SYMBOL_GPL(xenbus_map_ring);
 
@@ -579,14 +723,15 @@ 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 op = {
-		.host_addr = (unsigned long)vaddr,
-	};
+	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES];
 	unsigned int level;
+	int i;
+	bool leaked = false;
+	int err;
 
 	spin_lock(&xenbus_valloc_lock);
 	list_for_each_entry(node, &xenbus_valloc_pages, next) {
-		if (node->area->addr == vaddr) {
+		if (node->pv.area->addr == vaddr) {
 			list_del(&node->next);
 			goto found;
 		}
@@ -601,22 +746,41 @@ static int xenbus_unmap_ring_vfree_pv(struct xenbus_device *dev, void *vaddr)
 		return GNTST_bad_virt_addr;
 	}
 
-	op.handle = node->handle;
-	op.host_addr = arbitrary_virt_to_machine(
-		lookup_address((unsigned long)vaddr, &level)).maddr;
+	for (i = 0; i < node->nr_handles; i++) {
+		unsigned long addr;
+
+		memset(&unmap[i], 0, sizeof(unmap[i]));
+		addr = (unsigned long)vaddr + (PAGE_SIZE * i);
+		unmap[i].host_addr = arbitrary_virt_to_machine(
+			lookup_address(addr, &level)).maddr;
+		unmap[i].dev_bus_addr = 0;
+		unmap[i].handle = node->handles[i];
+	}
 
-	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, i))
 		BUG();
 
-	if (op.status == GNTST_okay)
-		free_vm_area(node->area);
+	err = GNTST_okay;
+	leaked = false;
+	for (i = 0; i < node->nr_handles; i++) {
+		if (unmap[i].status != GNTST_okay) {
+			leaked = true;
+			xenbus_dev_error(dev, unmap[i].status,
+					 "unmapping page at handle %d error %d",
+					 node->handles[i], unmap[i].status);
+			err = unmap[i].status;
+			break;
+		}
+	}
+
+	if (!leaked)
+		free_vm_area(node->pv.area);
 	else
-		xenbus_dev_error(dev, op.status,
-				 "unmapping page at handle %d error %d",
-				 node->handle, op.status);
+		pr_alert("leaking VM area %p size %u page(s)",
+			 node->pv.area, node->nr_handles);
 
 	kfree(node);
-	return op.status;
+	return err;
 }
 
 static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
@@ -624,10 +788,12 @@ 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;
 
 	spin_lock(&xenbus_valloc_lock);
 	list_for_each_entry(node, &xenbus_valloc_pages, next) {
-		addr = pfn_to_kaddr(page_to_pfn(node->page));
+		addr = node->hvm.addr;
 		if (addr == vaddr) {
 			list_del(&node->next);
 			goto found;
@@ -643,12 +809,16 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
 		return GNTST_bad_virt_addr;
 	}
 
-	rv = xenbus_unmap_ring(dev, node->handle, addr);
+	for (i = 0; i < node->nr_handles; i++)
+		addrs[i] = (unsigned long)pfn_to_kaddr(page_to_pfn(node->hvm.pages[i]));
 
+	rv = xenbus_unmap_ring(dev, node->handles, node->nr_handles,
+			       addrs);
 	if (!rv)
-		free_xenballooned_pages(1, &node->page);
+		vunmap(vaddr);
 	else
-		WARN(1, "Leaking %p\n", vaddr);
+		WARN(1, "Leaking %p, size %u page(s)\n", vaddr,
+		     node->nr_handles);
 
 	kfree(node);
 	return rv;
@@ -657,29 +827,44 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
 /**
  * xenbus_unmap_ring
  * @dev: xenbus device
- * @handle: grant handle
- * @vaddr: addr to unmap
+ * @handles: grant handle array
+ * @nr_handles: number of handles in the array
+ * @vaddrs: addresses to unmap
  *
- * Unmap a page of memory in this domain that was imported from another domain.
+ * Unmap memory in this domain that was imported from another domain.
  * Returns 0 on success and returns GNTST_* on error
  * (see xen/include/interface/grant_table.h).
  */
 int xenbus_unmap_ring(struct xenbus_device *dev,
-		      grant_handle_t handle, void *vaddr)
+		      grant_handle_t *handles, unsigned int nr_handles,
+		      unsigned long *vaddrs)
 {
-	struct gnttab_unmap_grant_ref op;
+	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_PAGES];
+	int i;
+	int err;
 
-	gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map, handle);
+	if (nr_handles > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
 
-	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+	for (i = 0; i < nr_handles; i++)
+		gnttab_set_unmap_op(&unmap[i], vaddrs[i],
+				    GNTMAP_host_map, handles[i]);
+
+	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap, i))
 		BUG();
 
-	if (op.status != GNTST_okay)
-		xenbus_dev_error(dev, op.status,
-				 "unmapping page at handle %d error %d",
-				 handle, op.status);
+	err = GNTST_okay;
+	for (i = 0; i < nr_handles; i++) {
+		if (unmap[i].status != GNTST_okay) {
+			xenbus_dev_error(dev, unmap[i].status,
+					 "unmapping page at handle %d error %d",
+					 handles[i], unmap[i].status);
+			err = unmap[i].status;
+			break;
+		}
+	}
 
-	return op.status;
+	return err;
 }
 EXPORT_SYMBOL_GPL(xenbus_unmap_ring);
 
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
new file mode 100644
index 000000000000..58a5389aec89
--- /dev/null
+++ b/drivers/xen/xlate_mmu.c
@@ -0,0 +1,143 @@
+/*
+ * MMU operations common to all auto-translated physmap guests.
+ *
+ * Copyright (C) 2015 Citrix Systems R&D Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include <linux/kernel.h>
+#include <linux/mm.h>
+
+#include <asm/xen/hypercall.h>
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/page.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
+
+/* map fgmfn of domid to lpfn in the current domain */
+static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
+			    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 = fgmfn;
+	xen_pfn_t gpfn = lpfn;
+	int err = 0;
+
+	set_xen_guest_handle(xatp.idxs, &idx);
+	set_xen_guest_handle(xatp.gpfns, &gpfn);
+	set_xen_guest_handle(xatp.errs, &err);
+
+	rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
+	return rc < 0 ? rc : err;
+}
+
+struct remap_data {
+	xen_pfn_t *fgmfn; /* foreign domain's gmfn */
+	pgprot_t prot;
+	domid_t  domid;
+	struct vm_area_struct *vma;
+	int index;
+	struct page **pages;
+	struct xen_remap_mfn_info *info;
+	int *err_ptr;
+	int mapped;
+};
+
+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;
+
+	rc = map_foreign_page(pfn, *info->fgmfn, info->domid);
+	*info->err_ptr++ = rc;
+	if (!rc) {
+		set_pte_at(info->vma->vm_mm, addr, ptep, pte);
+		info->mapped++;
+	}
+	info->fgmfn++;
+
+	return 0;
+}
+
+int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
+			      unsigned long addr,
+			      xen_pfn_t *mfn, int nr,
+			      int *err_ptr, pgprot_t prot,
+			      unsigned domid,
+			      struct page **pages)
+{
+	int err;
+	struct remap_data data;
+	unsigned long range = nr << 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.fgmfn = mfn;
+	data.prot  = prot;
+	data.domid = domid;
+	data.vma   = vma;
+	data.pages = pages;
+	data.index = 0;
+	data.err_ptr = err_ptr;
+	data.mapped = 0;
+
+	err = apply_to_page_range(vma->vm_mm, addr, range,
+				  remap_pte_fn, &data);
+	return err < 0 ? err : data.mapped;
+}
+EXPORT_SYMBOL_GPL(xen_xlate_remap_gfn_array);
+
+int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
+			      int nr, struct page **pages)
+{
+	int i;
+
+	for (i = 0; i < nr; i++) {
+		struct xen_remove_from_physmap xrp;
+		unsigned long pfn;
+
+		pfn = page_to_pfn(pages[i]);
+
+		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);