Merge tag 'stable/for-linus-4.1-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen features and fixes from David Vrabel:

- use a single source list of hypercalls, generating other tables etc.
at build time.

- add a "Xen PV" APIC driver to support >255 VCPUs in PV guests.

- significant performance improve to guest save/restore/migration.

- scsiback/front save/restore support.

- infrastructure for multi-page xenbus rings.

- misc fixes.

* tag 'stable/for-linus-4.1-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pci: Try harder to get PXM information for Xen
xenbus_client: Extend interface to support multi-page ring
xen-pciback: also support disabling of bus-mastering and memory-write-invalidate
xen: support suspend/resume in pvscsi frontend
xen: scsiback: add LUN of restored domain
xen-scsiback: define a pr_fmt macro with xen-pvscsi
xen/mce: fix up xen_late_init_mcelog() error handling
xen/privcmd: improve performance of MMAPBATCH_V2
xen: unify foreign GFN map/unmap for auto-xlated physmap guests
x86/xen/apic: WARN with details.
x86/xen: Provide a "Xen PV" APIC driver to support >255 VCPUs
xen/pciback: Don't print scary messages when unsupported by hypervisor.
xen: use generated hypercall symbols in arch/x86/xen/xen-head.S
xen: use generated hypervisor symbols in arch/x86/xen/trace.c
xen: synchronize include/xen/interface/xen.h with xen
xen: build infrastructure for generating hypercall depending symbols
xen: balloon: Use static attribute groups for sysfs entries
xen: pcpu: Use static attribute groups for sysfs entry

arch/arm/xen/enlighten.c

···
 
 static __read_mostly int xen_events_irq = -1;
 
-/* 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);
-	if (rc || err) {
-		pr_warn("Failed to map pfn to mfn rc:%d:%d pfn:%lx mfn:%lx\n",
-			rc, err, lpfn, fgmfn);
-		return 1;
-	}
-	return 0;
-}
-
-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;
-};
-
-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));
-
-	if (map_foreign_page(pfn, info->fgmfn, info->domid))
-		return -EFAULT;
-	set_pte_at(info->vma->vm_mm, addr, ptep, pte);
-
-	return 0;
-}
-
-int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
 			       unsigned long addr,
-			       xen_pfn_t mfn, int nr,
-			       pgprot_t prot, unsigned domid,
+			       xen_pfn_t *mfn, int nr,
+			       int *err_ptr, pgprot_t prot,
+			       unsigned domid,
 			       struct page **pages)
 {
-	int err;
-	struct remap_data data;
+	return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr,
+					 prot, domid, pages);
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
 
-	/* TBD: Batching, current sole caller only does page at a time */
-	if (nr > 1)
-		return -EINVAL;
-
-	data.fgmfn = mfn;
-	data.prot = prot;
-	data.domid = domid;
-	data.vma = vma;
-	data.index = 0;
-	data.pages = pages;
-	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
-				  remap_pte_fn, &data);
-	return err;
+/* Not used by XENFEAT_auto_translated guests. */
+int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
+                              unsigned long addr,
+                              xen_pfn_t mfn, int nr,
+                              pgprot_t prot, unsigned domid,
+                              struct page **pages)
+{
+	return -ENOSYS;
 }
 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
 
 int xen_unmap_domain_mfn_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 rc, pfn;
-
-		pfn = page_to_pfn(pages[i]);
-
-		xrp.domid = DOMID_SELF;
-		xrp.gpfn = pfn;
-		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
-		if (rc) {
-			pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
-				pfn, rc);
-			return rc;
-		}
-	}
-	return 0;
+	return xen_xlate_unmap_gfn_range(vma, nr, pages);
 }
 EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
 

arch/x86/syscalls/Makefile

···
 quiet_cmd_systbl = SYSTBL  $@
       cmd_systbl = $(CONFIG_SHELL) '$(systbl)' $< $@
 
+quiet_cmd_hypercalls = HYPERCALLS $@
+      cmd_hypercalls = $(CONFIG_SHELL) '$<' $@ $(filter-out $<,$^)
+
 syshdr_abi_unistd_32 := i386
 $(uapi)/unistd_32.h: $(syscall32) $(syshdr)
 	$(call if_changed,syshdr)
···
 $(out)/syscalls_64.h: $(syscall64) $(systbl)
 	$(call if_changed,systbl)
 
+$(out)/xen-hypercalls.h: $(srctree)/scripts/xen-hypercalls.sh
+	$(call if_changed,hypercalls)
+
+$(out)/xen-hypercalls.h: $(srctree)/include/xen/interface/xen*.h
+
 uapisyshdr-y			+= unistd_32.h unistd_64.h unistd_x32.h
 syshdr-y			+= syscalls_32.h
 syshdr-$(CONFIG_X86_64)		+= unistd_32_ia32.h unistd_64_x32.h
 syshdr-$(CONFIG_X86_64)		+= syscalls_64.h
+syshdr-$(CONFIG_XEN)		+= xen-hypercalls.h
 
 targets	+= $(uapisyshdr-y) $(syshdr-y)
 

arch/x86/xen/apic.c

···
 #include <xen/xen.h>
 #include <xen/interface/physdev.h>
 #include "xen-ops.h"
+#include "smp.h"
 
 static unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
 {
···
 	return 0xfd;
 }
 
+static unsigned long xen_set_apic_id(unsigned int x)
+{
+	WARN_ON(1);
+	return x;
+}
+
+static unsigned int xen_get_apic_id(unsigned long x)
+{
+	return ((x)>>24) & 0xFFu;
+}
+
+static u32 xen_apic_read(u32 reg)
+{
+	struct xen_platform_op op = {
+		.cmd = XENPF_get_cpuinfo,
+		.interface_version = XENPF_INTERFACE_VERSION,
+		.u.pcpu_info.xen_cpuid = 0,
+	};
+	int ret = 0;
+
+	/* Shouldn't need this as APIC is turned off for PV, and we only
+	 * get called on the bootup processor. But just in case. */
+	if (!xen_initial_domain() || smp_processor_id())
+		return 0;
+
+	if (reg == APIC_LVR)
+		return 0x10;
+#ifdef CONFIG_X86_32
+	if (reg == APIC_LDR)
+		return SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
+#endif
+	if (reg != APIC_ID)
+		return 0;
+
+	ret = HYPERVISOR_dom0_op(&op);
+	if (ret)
+		return 0;
+
+	return op.u.pcpu_info.apic_id << 24;
+}
+
+static void xen_apic_write(u32 reg, u32 val)
+{
+	/* Warn to see if there's any stray references */
+	WARN(1,"register: %x, value: %x\n", reg, val);
+}
+
+static u64 xen_apic_icr_read(void)
+{
+	return 0;
+}
+
+static void xen_apic_icr_write(u32 low, u32 id)
+{
+	/* Warn to see if there's any stray references */
+	WARN_ON(1);
+}
+
+static u32 xen_safe_apic_wait_icr_idle(void)
+{
+        return 0;
+}
+
+static int xen_apic_probe_pv(void)
+{
+	if (xen_pv_domain())
+		return 1;
+
+	return 0;
+}
+
+static int xen_madt_oem_check(char *oem_id, char *oem_table_id)
+{
+	return xen_pv_domain();
+}
+
+static int xen_id_always_valid(int apicid)
+{
+	return 1;
+}
+
+static int xen_id_always_registered(void)
+{
+	return 1;
+}
+
+static int xen_phys_pkg_id(int initial_apic_id, int index_msb)
+{
+	return initial_apic_id >> index_msb;
+}
+
+#ifdef CONFIG_X86_32
+static int xen_x86_32_early_logical_apicid(int cpu)
+{
+	/* Match with APIC_LDR read. Otherwise setup_local_APIC complains. */
+	return 1 << cpu;
+}
+#endif
+
+static void xen_noop(void)
+{
+}
+
+static void xen_silent_inquire(int apicid)
+{
+}
+
+static struct apic xen_pv_apic = {
+	.name 				= "Xen PV",
+	.probe 				= xen_apic_probe_pv,
+	.acpi_madt_oem_check		= xen_madt_oem_check,
+	.apic_id_valid 			= xen_id_always_valid,
+	.apic_id_registered 		= xen_id_always_registered,
+
+	/* .irq_delivery_mode - used in native_compose_msi_msg only */
+	/* .irq_dest_mode     - used in native_compose_msi_msg only */
+
+	.target_cpus			= default_target_cpus,
+	.disable_esr			= 0,
+	/* .dest_logical      -  default_send_IPI_ use it but we use our own. */
+	.check_apicid_used		= default_check_apicid_used, /* Used on 32-bit */
+
+	.vector_allocation_domain	= flat_vector_allocation_domain,
+	.init_apic_ldr			= xen_noop, /* setup_local_APIC calls it */
+
+	.ioapic_phys_id_map		= default_ioapic_phys_id_map, /* Used on 32-bit */
+	.setup_apic_routing		= NULL,
+	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
+	.apicid_to_cpu_present		= physid_set_mask_of_physid, /* Used on 32-bit */
+	.check_phys_apicid_present	= default_check_phys_apicid_present, /* smp_sanity_check needs it */
+	.phys_pkg_id			= xen_phys_pkg_id, /* detect_ht */
+
+	.get_apic_id 			= xen_get_apic_id,
+	.set_apic_id 			= xen_set_apic_id, /* Can be NULL on 32-bit. */
+	.apic_id_mask			= 0xFF << 24, /* Used by verify_local_APIC. Match with what xen_get_apic_id does. */
+
+	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
+
+#ifdef CONFIG_SMP
+	.send_IPI_mask 			= xen_send_IPI_mask,
+	.send_IPI_mask_allbutself 	= xen_send_IPI_mask_allbutself,
+	.send_IPI_allbutself 		= xen_send_IPI_allbutself,
+	.send_IPI_all 			= xen_send_IPI_all,
+	.send_IPI_self 			= xen_send_IPI_self,
+#endif
+	/* .wait_for_init_deassert- used  by AP bootup - smp_callin which we don't use */
+	.inquire_remote_apic		= xen_silent_inquire,
+
+	.read				= xen_apic_read,
+	.write				= xen_apic_write,
+	.eoi_write			= xen_apic_write,
+
+	.icr_read 			= xen_apic_icr_read,
+	.icr_write 			= xen_apic_icr_write,
+	.wait_icr_idle 			= xen_noop,
+	.safe_wait_icr_idle 		= xen_safe_apic_wait_icr_idle,
+
+#ifdef CONFIG_X86_32
+	/* generic_processor_info and setup_local_APIC. */
+	.x86_32_early_logical_apicid	= xen_x86_32_early_logical_apicid,
+#endif
+};
+
+static void __init xen_apic_check(void)
+{
+	if (apic == &xen_pv_apic)
+		return;
+
+	pr_info("Switched APIC routing from %s to %s.\n", apic->name,
+		xen_pv_apic.name);
+	apic = &xen_pv_apic;
+}
 void __init xen_init_apic(void)
 {
 	x86_io_apic_ops.read = xen_io_apic_read;
+	/* On PV guests the APIC CPUID bit is disabled so none of the
+	 * routines end up executing. */
+	if (!xen_initial_domain())
+		apic = &xen_pv_apic;
+
+	x86_platform.apic_post_init = xen_apic_check;
 }
+apic_driver(xen_pv_apic);

arch/x86/xen/enlighten.c

···
 {
 }
 
-#ifdef CONFIG_X86_LOCAL_APIC
-static unsigned long xen_set_apic_id(unsigned int x)
-{
-	WARN_ON(1);
-	return x;
-}
-static unsigned int xen_get_apic_id(unsigned long x)
-{
-	return ((x)>>24) & 0xFFu;
-}
-static u32 xen_apic_read(u32 reg)
-{
-	struct xen_platform_op op = {
-		.cmd = XENPF_get_cpuinfo,
-		.interface_version = XENPF_INTERFACE_VERSION,
-		.u.pcpu_info.xen_cpuid = 0,
-	};
-	int ret = 0;
-
-	/* Shouldn't need this as APIC is turned off for PV, and we only
-	 * get called on the bootup processor. But just in case. */
-	if (!xen_initial_domain() || smp_processor_id())
-		return 0;
-
-	if (reg == APIC_LVR)
-		return 0x10;
-
-	if (reg != APIC_ID)
-		return 0;
-
-	ret = HYPERVISOR_dom0_op(&op);
-	if (ret)
-		return 0;
-
-	return op.u.pcpu_info.apic_id << 24;
-}
-
-static void xen_apic_write(u32 reg, u32 val)
-{
-	/* Warn to see if there's any stray references */
-	WARN_ON(1);
-}
-
-static u64 xen_apic_icr_read(void)
-{
-	return 0;
-}
-
-static void xen_apic_icr_write(u32 low, u32 id)
-{
-	/* Warn to see if there's any stray references */
-	WARN_ON(1);
-}
-
-static void xen_apic_wait_icr_idle(void)
-{
-        return;
-}
-
-static u32 xen_safe_apic_wait_icr_idle(void)
-{
-        return 0;
-}
-
-static void set_xen_basic_apic_ops(void)
-{
-	apic->read = xen_apic_read;
-	apic->write = xen_apic_write;
-	apic->icr_read = xen_apic_icr_read;
-	apic->icr_write = xen_apic_icr_write;
-	apic->wait_icr_idle = xen_apic_wait_icr_idle;
-	apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
-	apic->set_apic_id = xen_set_apic_id;
-	apic->get_apic_id = xen_get_apic_id;
-
-#ifdef CONFIG_SMP
-	apic->send_IPI_allbutself = xen_send_IPI_allbutself;
-	apic->send_IPI_mask_allbutself = xen_send_IPI_mask_allbutself;
-	apic->send_IPI_mask = xen_send_IPI_mask;
-	apic->send_IPI_all = xen_send_IPI_all;
-	apic->send_IPI_self = xen_send_IPI_self;
-#endif
-}
-
-#endif
-
 static void xen_clts(void)
 {
 	struct multicall_space mcs;
···
 	/*
 	 * set up the basic apic ops.
 	 */
-	set_xen_basic_apic_ops();
+	xen_init_apic();
 #endif
 
 	if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) {
···
 
 		if (HYPERVISOR_dom0_op(&op) == 0)
 			boot_params.kbd_status = op.u.firmware_info.u.kbd_shift_flags;
-
-		xen_init_apic();
 
 		/* Make sure ACS will be enabled */
 		pci_request_acs();

arch/x86/xen/mmu.c

···
 }
 #endif
 
-#ifdef CONFIG_XEN_PVH
-/*
- * Map foreign gfn (fgfn), to local pfn (lpfn). This for the user
- * space creating new guest on pvh dom0 and needing to map domU pages.
- */
-static int xlate_add_to_p2m(unsigned long lpfn, unsigned long fgfn,
-			    unsigned int domid)
-{
-	int rc, err = 0;
-	xen_pfn_t gpfn = lpfn;
-	xen_ulong_t idx = fgfn;
-
-	struct xen_add_to_physmap_range xatp = {
-		.domid = DOMID_SELF,
-		.foreign_domid = domid,
-		.size = 1,
-		.space = XENMAPSPACE_gmfn_foreign,
-	};
-	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);
-	if (rc < 0)
-		return rc;
-	return err;
-}
-
-static int xlate_remove_from_p2m(unsigned long spfn, int count)
-{
-	struct xen_remove_from_physmap xrp;
-	int i, rc;
-
-	for (i = 0; i < count; i++) {
-		xrp.domid = DOMID_SELF;
-		xrp.gpfn = spfn+i;
-		rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
-		if (rc)
-			break;
-	}
-	return rc;
-}
-
-struct xlate_remap_data {
-	unsigned long fgfn; /* foreign domain's gfn */
-	pgprot_t prot;
-	domid_t  domid;
-	int index;
-	struct page **pages;
-};
-
-static int xlate_map_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
-			    void *data)
-{
-	int rc;
-	struct xlate_remap_data *remap = data;
-	unsigned long pfn = page_to_pfn(remap->pages[remap->index++]);
-	pte_t pteval = pte_mkspecial(pfn_pte(pfn, remap->prot));
-
-	rc = xlate_add_to_p2m(pfn, remap->fgfn, remap->domid);
-	if (rc)
-		return rc;
-	native_set_pte(ptep, pteval);
-
-	return 0;
-}
-
-static int xlate_remap_gfn_range(struct vm_area_struct *vma,
-				 unsigned long addr, unsigned long mfn,
-				 int nr, pgprot_t prot, unsigned domid,
-				 struct page **pages)
-{
-	int err;
-	struct xlate_remap_data pvhdata;
-
-	BUG_ON(!pages);
-
-	pvhdata.fgfn = mfn;
-	pvhdata.prot = prot;
-	pvhdata.domid = domid;
-	pvhdata.index = 0;
-	pvhdata.pages = pages;
-	err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
-				  xlate_map_pte_fn, &pvhdata);
-	flush_tlb_all();
-	return err;
-}
-#endif
-
 #define REMAP_BATCH_SIZE 16
 
 struct remap_data {
-	unsigned long mfn;
+	xen_pfn_t *mfn;
+	bool contiguous;
 	pgprot_t prot;
 	struct mmu_update *mmu_update;
 };
···
 				 unsigned long addr, void *data)
 {
 	struct remap_data *rmd = data;
-	pte_t pte = pte_mkspecial(mfn_pte(rmd->mfn++, rmd->prot));
+	pte_t pte = pte_mkspecial(mfn_pte(*rmd->mfn, rmd->prot));
+
+	/* If we have a contigious range, just update the mfn itself,
+	   else update pointer to be "next mfn". */
+	if (rmd->contiguous)
+		(*rmd->mfn)++;
+	else
+		rmd->mfn++;
 
 	rmd->mmu_update->ptr = virt_to_machine(ptep).maddr;
 	rmd->mmu_update->val = pte_val_ma(pte);
···
 	return 0;
 }
 
-int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
-			       unsigned long addr,
-			       xen_pfn_t mfn, int nr,
-			       pgprot_t prot, unsigned domid,
-			       struct page **pages)
-
+static int do_remap_mfn(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 = 0;
 	struct remap_data rmd;
 	struct mmu_update mmu_update[REMAP_BATCH_SIZE];
-	int batch;
 	unsigned long range;
-	int err = 0;
+	int mapped = 0;
 
 	BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO)));
 
 	if (xen_feature(XENFEAT_auto_translated_physmap)) {
 #ifdef CONFIG_XEN_PVH
 		/* We need to update the local page tables and the xen HAP */
-		return xlate_remap_gfn_range(vma, addr, mfn, nr, prot,
-					     domid, pages);
+		return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr,
+						 prot, domid, pages);
 #else
 		return -EINVAL;
 #endif
···
 
 	rmd.mfn = mfn;
 	rmd.prot = prot;
+	/* We use the err_ptr to indicate if there we are doing a contigious
+	 * mapping or a discontigious mapping. */
+	rmd.contiguous = !err_ptr;
 
 	while (nr) {
-		batch = min(REMAP_BATCH_SIZE, nr);
+		int index = 0;
+		int done = 0;
+		int batch = min(REMAP_BATCH_SIZE, nr);
+		int batch_left = batch;
 		range = (unsigned long)batch << PAGE_SHIFT;
 
 		rmd.mmu_update = mmu_update;
···
 		if (err)
 			goto out;
 
-		err = HYPERVISOR_mmu_update(mmu_update, batch, NULL, domid);
-		if (err < 0)
-			goto out;
+		/* We record the error for each page that gives an error, but
+		 * continue mapping until the whole set is done */
+		do {
+			int i;
+
+			err = HYPERVISOR_mmu_update(&mmu_update[index],
+						    batch_left, &done, domid);
+
+			/*
+			 * @err_ptr may be the same buffer as @mfn, so
+			 * only clear it after each chunk of @mfn is
+			 * used.
+			 */
+			if (err_ptr) {
+				for (i = index; i < index + done; i++)
+					err_ptr[i] = 0;
+			}
+			if (err < 0) {
+				if (!err_ptr)
+					goto out;
+				err_ptr[i] = err;
+				done++; /* Skip failed frame. */
+			} else
+				mapped += done;
+			batch_left -= done;
+			index += done;
+		} while (batch_left);
 
 		nr -= batch;
 		addr += range;
+		if (err_ptr)
+			err_ptr += batch;
 	}
-
-	err = 0;
 out:
 
 	xen_flush_tlb_all();
 
-	return err;
+	return err < 0 ? err : mapped;
+}
+
+int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
+			       unsigned long addr,
+			       xen_pfn_t mfn, int nr,
+			       pgprot_t prot, unsigned domid,
+			       struct page **pages)
+{
+	return do_remap_mfn(vma, addr, &mfn, nr, NULL, prot, domid, pages);
 }
 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
+
+int xen_remap_domain_mfn_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)
+{
+	/* We BUG_ON because it's a programmer error to pass a NULL err_ptr,
+	 * and the consequences later is quite hard to detect what the actual
+	 * cause of "wrong memory was mapped in".
+	 */
+	BUG_ON(err_ptr == NULL);
+	return do_remap_mfn(vma, addr, mfn, nr, err_ptr, prot, domid, pages);
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
+
 
 /* Returns: 0 success */
 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
···
 		return 0;
 
 #ifdef CONFIG_XEN_PVH
-	while (numpgs--) {
-		/*
-		 * The mmu has already cleaned up the process mmu
-		 * resources at this point (lookup_address will return
-		 * NULL).
-		 */
-		unsigned long pfn = page_to_pfn(pages[numpgs]);
-
-		xlate_remove_from_p2m(pfn, 1);
-	}
-	/*
-	 * We don't need to flush tlbs because as part of
-	 * xlate_remove_from_p2m, the hypervisor will do tlb flushes
-	 * after removing the p2m entries from the EPT/NPT
-	 */
-	return 0;
+	return xen_xlate_unmap_gfn_range(vma, numpgs, pages);
 #else
 	return -EINVAL;
 #endif

arch/x86/xen/trace.c

···
 #include <linux/ftrace.h>
 #include <xen/interface/xen.h>
+#include <xen/interface/xen-mca.h>
 
-#define N(x)	[__HYPERVISOR_##x] = "("#x")"
+#define HYPERCALL(x)	[__HYPERVISOR_##x] = "("#x")",
 static const char *xen_hypercall_names[] = {
-	N(set_trap_table),
-	N(mmu_update),
-	N(set_gdt),
-	N(stack_switch),
-	N(set_callbacks),
-	N(fpu_taskswitch),
-	N(sched_op_compat),
-	N(dom0_op),
-	N(set_debugreg),
-	N(get_debugreg),
-	N(update_descriptor),
-	N(memory_op),
-	N(multicall),
-	N(update_va_mapping),
-	N(set_timer_op),
-	N(event_channel_op_compat),
-	N(xen_version),
-	N(console_io),
-	N(physdev_op_compat),
-	N(grant_table_op),
-	N(vm_assist),
-	N(update_va_mapping_otherdomain),
-	N(iret),
-	N(vcpu_op),
-	N(set_segment_base),
-	N(mmuext_op),
-	N(acm_op),
-	N(nmi_op),
-	N(sched_op),
-	N(callback_op),
-	N(xenoprof_op),
-	N(event_channel_op),
-	N(physdev_op),
-	N(hvm_op),
-
-/* Architecture-specific hypercall definitions. */
-	N(arch_0),
-	N(arch_1),
-	N(arch_2),
-	N(arch_3),
-	N(arch_4),
-	N(arch_5),
-	N(arch_6),
-	N(arch_7),
+#include <asm/xen-hypercalls.h>
 };
-#undef N
+#undef HYPERCALL
 
 static const char *xen_hypercall_name(unsigned op)
 {

arch/x86/xen/xen-head.S

···
 
 #include <xen/interface/elfnote.h>
 #include <xen/interface/features.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/xen-mca.h>
 #include <asm/xen/interface.h>
 
 #ifdef CONFIG_XEN_PVH
···
 .pushsection .text
 	.balign PAGE_SIZE
 ENTRY(hypercall_page)
-#define NEXT_HYPERCALL(x) \
-	ENTRY(xen_hypercall_##x) \
-	.skip 32
+	.skip PAGE_SIZE
 
-NEXT_HYPERCALL(set_trap_table)
-NEXT_HYPERCALL(mmu_update)
-NEXT_HYPERCALL(set_gdt)
-NEXT_HYPERCALL(stack_switch)
-NEXT_HYPERCALL(set_callbacks)
-NEXT_HYPERCALL(fpu_taskswitch)
-NEXT_HYPERCALL(sched_op_compat)
-NEXT_HYPERCALL(platform_op)
-NEXT_HYPERCALL(set_debugreg)
-NEXT_HYPERCALL(get_debugreg)
-NEXT_HYPERCALL(update_descriptor)
-NEXT_HYPERCALL(ni)
-NEXT_HYPERCALL(memory_op)
-NEXT_HYPERCALL(multicall)
-NEXT_HYPERCALL(update_va_mapping)
-NEXT_HYPERCALL(set_timer_op)
-NEXT_HYPERCALL(event_channel_op_compat)
-NEXT_HYPERCALL(xen_version)
-NEXT_HYPERCALL(console_io)
-NEXT_HYPERCALL(physdev_op_compat)
-NEXT_HYPERCALL(grant_table_op)
-NEXT_HYPERCALL(vm_assist)
-NEXT_HYPERCALL(update_va_mapping_otherdomain)
-NEXT_HYPERCALL(iret)
-NEXT_HYPERCALL(vcpu_op)
-NEXT_HYPERCALL(set_segment_base)
-NEXT_HYPERCALL(mmuext_op)
-NEXT_HYPERCALL(xsm_op)
-NEXT_HYPERCALL(nmi_op)
-NEXT_HYPERCALL(sched_op)
-NEXT_HYPERCALL(callback_op)
-NEXT_HYPERCALL(xenoprof_op)
-NEXT_HYPERCALL(event_channel_op)
-NEXT_HYPERCALL(physdev_op)
-NEXT_HYPERCALL(hvm_op)
-NEXT_HYPERCALL(sysctl)
-NEXT_HYPERCALL(domctl)
-NEXT_HYPERCALL(kexec_op)
-NEXT_HYPERCALL(tmem_op) /* 38 */
-ENTRY(xen_hypercall_rsvr)
-	.skip 320
-NEXT_HYPERCALL(mca) /* 48 */
-NEXT_HYPERCALL(arch_1)
-NEXT_HYPERCALL(arch_2)
-NEXT_HYPERCALL(arch_3)
-NEXT_HYPERCALL(arch_4)
-NEXT_HYPERCALL(arch_5)
-NEXT_HYPERCALL(arch_6)
-	.balign PAGE_SIZE
+#define HYPERCALL(n) \
+	.equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \
+	.type xen_hypercall_##n, @function; .size xen_hypercall_##n, 32
+#include <asm/xen-hypercalls.h>
+#undef HYPERCALL
+
 .popsection
 
 	ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS,       .asciz "linux")

drivers/block/xen-blkback/xenbus.c

···
 	return ERR_PTR(-ENOMEM);
 }
 
-static int xen_blkif_map(struct xen_blkif *blkif, unsigned long shared_page,
+static int xen_blkif_map(struct xen_blkif *blkif, grant_ref_t gref,
 			 unsigned int evtchn)
 {
 	int err;
···
 	if (blkif->irq)
 		return 0;
 
-	err = xenbus_map_ring_valloc(blkif->be->dev, shared_page, &blkif->blk_ring);
+	err = xenbus_map_ring_valloc(blkif->be->dev, &gref, 1,
+				     &blkif->blk_ring);
 	if (err < 0)
 		return err;
 

drivers/block/xen-blkfront.c

···
 			 struct blkfront_info *info)
 {
 	struct blkif_sring *sring;
+	grant_ref_t gref;
 	int err;
 
 	info->ring_ref = GRANT_INVALID_REF;
···
 	SHARED_RING_INIT(sring);
 	FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
 
-	err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring));
+	err = xenbus_grant_ring(dev, info->ring.sring, 1, &gref);
 	if (err < 0) {
 		free_page((unsigned long)sring);
 		info->ring.sring = NULL;
 		goto fail;
 	}
-	info->ring_ref = err;
+	info->ring_ref = gref;
 
 	err = xenbus_alloc_evtchn(dev, &info->evtchn);
 	if (err)

drivers/char/tpm/xen-tpmfront.c

···
 	struct xenbus_transaction xbt;
 	const char *message = NULL;
 	int rv;
+	grant_ref_t gref;
 
 	priv->shr = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
 	if (!priv->shr) {
···
 		return -ENOMEM;
 	}
 
-	rv = xenbus_grant_ring(dev, virt_to_mfn(priv->shr));
+	rv = xenbus_grant_ring(dev, &priv->shr, 1, &gref);
 	if (rv < 0)
 		return rv;
 
-	priv->ring_ref = rv;
+	priv->ring_ref = gref;
 
 	rv = xenbus_alloc_evtchn(dev, &priv->evtchn);
 	if (rv)

drivers/net/xen-netback/netback.c

···
 	int err = -ENOMEM;
 
 	err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif),
-				     tx_ring_ref, &addr);
+				     &tx_ring_ref, 1, &addr);
 	if (err)
 		goto err;
 
···
 	BACK_RING_INIT(&queue->tx, txs, PAGE_SIZE);
 
 	err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif),
-				     rx_ring_ref, &addr);
+				     &rx_ring_ref, 1, &addr);
 	if (err)
 		goto err;
 

drivers/net/xen-netfront.c

···
 {
 	struct xen_netif_tx_sring *txs;
 	struct xen_netif_rx_sring *rxs;
+	grant_ref_t gref;
 	int err;
 
 	queue->tx_ring_ref = GRANT_INVALID_REF;
···
 	SHARED_RING_INIT(txs);
 	FRONT_RING_INIT(&queue->tx, txs, PAGE_SIZE);
 
-	err = xenbus_grant_ring(dev, virt_to_mfn(txs));
+	err = xenbus_grant_ring(dev, txs, 1, &gref);
 	if (err < 0)
 		goto grant_tx_ring_fail;
-	queue->tx_ring_ref = err;
+	queue->tx_ring_ref = gref;
 
 	rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
 	if (!rxs) {
···
 	SHARED_RING_INIT(rxs);
 	FRONT_RING_INIT(&queue->rx, rxs, PAGE_SIZE);
 
-	err = xenbus_grant_ring(dev, virt_to_mfn(rxs));
+	err = xenbus_grant_ring(dev, rxs, 1, &gref);
 	if (err < 0)
 		goto grant_rx_ring_fail;
-	queue->rx_ring_ref = err;
+	queue->rx_ring_ref = gref;
 
 	if (feature_split_evtchn)
 		err = setup_netfront_split(queue);

drivers/pci/xen-pcifront.c

···
 {
 	int err = 0;
 	struct xenbus_transaction trans;
+	grant_ref_t gref;
 
-	err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
+	err = xenbus_grant_ring(pdev->xdev, pdev->sh_info, 1, &gref);
 	if (err < 0)
 		goto out;
 
-	pdev->gnt_ref = err;
+	pdev->gnt_ref = gref;
 
 	err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
 	if (err)

drivers/scsi/xen-scsifront.c

···
 
 #define VSCSIFRONT_OP_ADD_LUN	1
 #define VSCSIFRONT_OP_DEL_LUN	2
+#define VSCSIFRONT_OP_READD_LUN	3
 
 /* Tuning point. */
 #define VSCSIIF_DEFAULT_CMD_PER_LUN 10
···
 	DECLARE_BITMAP(shadow_free_bitmap, VSCSIIF_MAX_REQS);
 	struct vscsifrnt_shadow *shadow[VSCSIIF_MAX_REQS];
 
+	/* Following items are protected by the host lock. */
 	wait_queue_head_t wq_sync;
+	wait_queue_head_t wq_pause;
 	unsigned int wait_ring_available:1;
+	unsigned int waiting_pause:1;
+	unsigned int pause:1;
+	unsigned callers;
 
 	char dev_state_path[64];
 	struct task_struct *curr;
···
 	wake_up(&shadow->wq_reset);
 }
 
-static int scsifront_cmd_done(struct vscsifrnt_info *info)
+static void scsifront_do_response(struct vscsifrnt_info *info,
+				  struct vscsiif_response *ring_rsp)
+{
+	if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
+		 test_bit(ring_rsp->rqid, info->shadow_free_bitmap),
+		 "illegal rqid %u returned by backend!\n", ring_rsp->rqid))
+		return;
+
+	if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB)
+		scsifront_cdb_cmd_done(info, ring_rsp);
+	else
+		scsifront_sync_cmd_done(info, ring_rsp);
+}
+
+static int scsifront_ring_drain(struct vscsifrnt_info *info)
 {
 	struct vscsiif_response *ring_rsp;
 	RING_IDX i, rp;
 	int more_to_do = 0;
-	unsigned long flags;
-
-	spin_lock_irqsave(info->host->host_lock, flags);
 
 	rp = info->ring.sring->rsp_prod;
 	rmb();	/* ordering required respective to dom0 */
 	for (i = info->ring.rsp_cons; i != rp; i++) {
-
 		ring_rsp = RING_GET_RESPONSE(&info->ring, i);
-
-		if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS ||
-			 test_bit(ring_rsp->rqid, info->shadow_free_bitmap),
-			 "illegal rqid %u returned by backend!\n",
-			 ring_rsp->rqid))
-			continue;
-
-		if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB)
-			scsifront_cdb_cmd_done(info, ring_rsp);
-		else
-			scsifront_sync_cmd_done(info, ring_rsp);
+		scsifront_do_response(info, ring_rsp);
 	}
 
 	info->ring.rsp_cons = i;
···
 		RING_FINAL_CHECK_FOR_RESPONSES(&info->ring, more_to_do);
 	else
 		info->ring.sring->rsp_event = i + 1;
+
+	return more_to_do;
+}
+
+static int scsifront_cmd_done(struct vscsifrnt_info *info)
+{
+	int more_to_do;
+	unsigned long flags;
+
+	spin_lock_irqsave(info->host->host_lock, flags);
+
+	more_to_do = scsifront_ring_drain(info);
 
 	info->wait_ring_available = 0;
 
···
 		cond_resched();
 
 	return IRQ_HANDLED;
+}
+
+static void scsifront_finish_all(struct vscsifrnt_info *info)
+{
+	unsigned i;
+	struct vscsiif_response resp;
+
+	scsifront_ring_drain(info);
+
+	for (i = 0; i < VSCSIIF_MAX_REQS; i++) {
+		if (test_bit(i, info->shadow_free_bitmap))
+			continue;
+		resp.rqid = i;
+		resp.sense_len = 0;
+		resp.rslt = DID_RESET << 16;
+		resp.residual_len = 0;
+		scsifront_do_response(info, &resp);
+	}
 }
 
 static int map_data_for_request(struct vscsifrnt_info *info,
···
 	return ring_req;
 }
 
+static int scsifront_enter(struct vscsifrnt_info *info)
+{
+	if (info->pause)
+		return 1;
+	info->callers++;
+	return 0;
+}
+
+static void scsifront_return(struct vscsifrnt_info *info)
+{
+	info->callers--;
+	if (info->callers)
+		return;
+
+	if (!info->waiting_pause)
+		return;
+
+	info->waiting_pause = 0;
+	wake_up(&info->wq_pause);
+}
+
 static int scsifront_queuecommand(struct Scsi_Host *shost,
 				  struct scsi_cmnd *sc)
 {
···
 	uint16_t rqid;
 
 	spin_lock_irqsave(shost->host_lock, flags);
+	if (scsifront_enter(info)) {
+		spin_unlock_irqrestore(shost->host_lock, flags);
+		return SCSI_MLQUEUE_HOST_BUSY;
+	}
 	if (RING_FULL(&info->ring))
 		goto busy;
 
···
 	if (err < 0) {
 		pr_debug("%s: err %d\n", __func__, err);
 		scsifront_put_rqid(info, rqid);
+		scsifront_return(info);
 		spin_unlock_irqrestore(shost->host_lock, flags);
 		if (err == -ENOMEM)
 			return SCSI_MLQUEUE_HOST_BUSY;
···
 	}
 
 	scsifront_do_request(info);
+	scsifront_return(info);
 	spin_unlock_irqrestore(shost->host_lock, flags);
 
 	return 0;
 
 busy:
+	scsifront_return(info);
 	spin_unlock_irqrestore(shost->host_lock, flags);
 	pr_debug("%s: busy\n", __func__);
 	return SCSI_MLQUEUE_HOST_BUSY;
···
 			if (ring_req)
 				break;
 		}
-		if (err) {
+		if (err || info->pause) {
 			spin_unlock_irq(host->host_lock);
 			kfree(shadow);
 			return FAILED;
···
 		err = wait_event_interruptible(info->wq_sync,
 					       !info->wait_ring_available);
 		spin_lock_irq(host->host_lock);
+	}
+
+	if (scsifront_enter(info)) {
+		spin_unlock_irq(host->host_lock);
+		return FAILED;
 	}
 
 	ring_req->act = act;
···
 		err = FAILED;
 	}
 
+	scsifront_return(info);
 	spin_unlock_irq(host->host_lock);
 	return err;
 }
···
 {
 	struct xenbus_device *dev = info->dev;
 	struct vscsiif_sring *sring;
+	grant_ref_t gref;
 	int err = -ENOMEM;
 
 	/***** Frontend to Backend ring start *****/
···
 	SHARED_RING_INIT(sring);
 	FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);
 
-	err = xenbus_grant_ring(dev, virt_to_mfn(sring));
+	err = xenbus_grant_ring(dev, sring, 1, &gref);
 	if (err < 0) {
 		free_page((unsigned long)sring);
 		xenbus_dev_fatal(dev, err,
 			"fail to grant shared ring (Front to Back)");
 		return err;
 	}
-	info->ring_ref = err;
+	info->ring_ref = gref;
 
 	err = xenbus_alloc_evtchn(dev, &info->evtchn);
 	if (err) {
···
 				  (unsigned long)info->ring.sring);
 
 	return err;
+}
+
+static void scsifront_free_ring(struct vscsifrnt_info *info)
+{
+	unbind_from_irqhandler(info->irq, info);
+	gnttab_end_foreign_access(info->ring_ref, 0,
+				  (unsigned long)info->ring.sring);
 }
 
 static int scsifront_init_ring(struct vscsifrnt_info *info)
···
 fail:
 	xenbus_transaction_end(xbt, 1);
 free_sring:
-	unbind_from_irqhandler(info->irq, info);
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
+	scsifront_free_ring(info);
 
 	return err;
 }
···
 	}
 
 	init_waitqueue_head(&info->wq_sync);
+	init_waitqueue_head(&info->wq_pause);
 	spin_lock_init(&info->shadow_lock);
 
 	snprintf(name, TASK_COMM_LEN, "vscsiif.%d", host->host_no);
···
 	return 0;
 
 free_sring:
-	unbind_from_irqhandler(info->irq, info);
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
+	scsifront_free_ring(info);
 	scsi_host_put(host);
+	return err;
+}
+
+static int scsifront_resume(struct xenbus_device *dev)
+{
+	struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev);
+	struct Scsi_Host *host = info->host;
+	int err;
+
+	spin_lock_irq(host->host_lock);
+
+	/* Finish all still pending commands. */
+	scsifront_finish_all(info);
+
+	spin_unlock_irq(host->host_lock);
+
+	/* Reconnect to dom0. */
+	scsifront_free_ring(info);
+	err = scsifront_init_ring(info);
+	if (err) {
+		dev_err(&dev->dev, "fail to resume %d\n", err);
+		scsi_host_put(host);
+		return err;
+	}
+
+	xenbus_switch_state(dev, XenbusStateInitialised);
+
+	return 0;
+}
+
+static int scsifront_suspend(struct xenbus_device *dev)
+{
+	struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev);
+	struct Scsi_Host *host = info->host;
+	int err = 0;
+
+	/* No new commands for the backend. */
+	spin_lock_irq(host->host_lock);
+	info->pause = 1;
+	while (info->callers && !err) {
+		info->waiting_pause = 1;
+		info->wait_ring_available = 0;
+		spin_unlock_irq(host->host_lock);
+		wake_up(&info->wq_sync);
+		err = wait_event_interruptible(info->wq_pause,
+					       !info->waiting_pause);
+		spin_lock_irq(host->host_lock);
+	}
+	spin_unlock_irq(host->host_lock);
 	return err;
 }
 
···
 	}
 	mutex_unlock(&scsifront_mutex);
 
-	gnttab_end_foreign_access(info->ring_ref, 0,
-				  (unsigned long)info->ring.sring);
-	unbind_from_irqhandler(info->irq, info);
-
+	scsifront_free_ring(info);
 	scsi_host_put(info->host);
 
 	return 0;
···
 				scsi_device_put(sdev);
 			}
 			break;
+		case VSCSIFRONT_OP_READD_LUN:
+			if (device_state == XenbusStateConnected)
+				xenbus_printf(XBT_NIL, dev->nodename,
+					      info->dev_state_path,
+					      "%d", XenbusStateConnected);
+			break;
 		default:
 			break;
 		}
···
 static void scsifront_read_backend_params(struct xenbus_device *dev,
 					  struct vscsifrnt_info *info)
 {
-	unsigned int sg_grant;
+	unsigned int sg_grant, nr_segs;
 	int ret;
 	struct Scsi_Host *host = info->host;
 
 	ret = xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg-grant", "%u",
 			   &sg_grant);
-	if (ret == 1 && sg_grant) {
-		sg_grant = min_t(unsigned int, sg_grant, SG_ALL);
-		sg_grant = max_t(unsigned int, sg_grant, VSCSIIF_SG_TABLESIZE);
-		host->sg_tablesize = min_t(unsigned int, sg_grant,
+	if (ret != 1)
+		sg_grant = 0;
+	nr_segs = min_t(unsigned int, sg_grant, SG_ALL);
+	nr_segs = max_t(unsigned int, nr_segs, VSCSIIF_SG_TABLESIZE);
+	nr_segs = min_t(unsigned int, nr_segs,
 			VSCSIIF_SG_TABLESIZE * PAGE_SIZE /
 			sizeof(struct scsiif_request_segment));
-		host->max_sectors = (host->sg_tablesize - 1) * PAGE_SIZE / 512;
-	}
-	dev_info(&dev->dev, "using up to %d SG entries\n", host->sg_tablesize);
+
+	if (!info->pause && sg_grant)
+		dev_info(&dev->dev, "using up to %d SG entries\n", nr_segs);
+	else if (info->pause && nr_segs < host->sg_tablesize)
+		dev_warn(&dev->dev,
+			 "SG entries decreased from %d to %u - device may not work properly anymore\n",
+			 host->sg_tablesize, nr_segs);
+
+	host->sg_tablesize = nr_segs;
+	host->max_sectors = (nr_segs - 1) * PAGE_SIZE / 512;
 }
 
 static void scsifront_backend_changed(struct xenbus_device *dev,
···
 
 	case XenbusStateConnected:
 		scsifront_read_backend_params(dev, info);
+
+		if (info->pause) {
+			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_READD_LUN);
+			xenbus_switch_state(dev, XenbusStateConnected);
+			info->pause = 0;
+			return;
+		}
+
 		if (xenbus_read_driver_state(dev->nodename) ==
 		    XenbusStateInitialised)
 			scsifront_do_lun_hotplug(info, VSCSIFRONT_OP_ADD_LUN);
···
 	.ids			= scsifront_ids,
 	.probe			= scsifront_probe,
 	.remove			= scsifront_remove,
+	.resume			= scsifront_resume,
+	.suspend		= scsifront_suspend,
 	.otherend_changed	= scsifront_backend_changed,
 };
 

drivers/xen/Kconfig

···
 	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

drivers/xen/Makefile

···
 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

drivers/xen/mcelog.c

···
 
 static int __init xen_late_init_mcelog(void)
 {
-	/* 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();
-	}
+	int ret;
 
-	return -ENODEV;
+	/* Only DOM0 is responsible for MCE logging */
+	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 0;
+
+deregister:
+	misc_deregister(&xen_mce_chrdev_device);
+	return ret;
 }
 device_initcall(xen_late_init_mcelog);

drivers/xen/pci.c

···
 
 #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>
···
 
 #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;
 

drivers/xen/pcpu.c

···
 }
 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);
···
 		return;
 
 	dev = &pcpu->dev;
-	if (dev->id)
-		device_remove_file(dev, &dev_attr_online);
-
 	/* pcpu remove would be implicitly done */
 	device_unregister(dev);
 }
···
 	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) {
 		pcpu_release(dev);
 		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;

drivers/xen/privcmd.c

···
 	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;
···
 /* 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 {
···
 				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
 			st->user_err++;
 	}
 
+	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;
 }
 
···
 	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);
 
···
 		/* 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;
 

drivers/xen/xen-balloon.c

···
 		   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[] = {
···
 	.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,
···
 
 static int register_balloon(struct device *dev)
 {
-	int i, error;
+	int error;
 
 	error = subsys_system_register(&balloon_subsys, NULL);
 	if (error)
···
 
 	dev->id = 0;
 	dev->bus = &balloon_subsys;
+	dev->groups = balloon_groups;
 
 	error = device_register(dev);
 	if (error) {
···
 		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");

drivers/xen/xen-pciback/conf_space_header.c

···
 			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",
···
 				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;

drivers/xen/xen-pciback/pci_stub.c

···
 		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);
 	}
···
 		};
 
 		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);
 	}

drivers/xen/xen-pciback/xenbus.c

···
 		"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.");

drivers/xen/xen-scsiback.c

···
  * IN THE SOFTWARE.
  */
 
+#define pr_fmt(fmt) "xen-pvscsi: " fmt
+
 #include <stdarg.h>
 
 #include <linux/module.h>
···
 
 #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
···
 {
 	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));
···
 	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 {
···
 	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]),
···
 		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;
 	}
···
 			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)
···
 	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;
···
 		(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;
 	}
···
 
 	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;
···
 			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);
···
 	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;
 
···
 
 	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;
 	}
 
···
 	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;
 	}
 
···
 		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;
 		}
···
 }
 
 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);
 	}
···
 	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);
 	}
 }
 
···
 
 	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:
···
 			/* 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;
 	}
···
 	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");
···
 	return 0;
 
 fail:
-	pr_warn("xen-pvscsi: %s failed\n", __func__);
+	pr_warn("%s failed\n", __func__);
 	scsiback_remove(dev);
 
 	return err;
···
 	}
 	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;
···
 	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);
···
 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)
···
 		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)) {
···
 		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);
 
···
 	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);
···
 	 */
 	scsiback_drop_nexus(tpg);
 	/*
-	 * Deregister the se_tpg from TCM..
+	 * Deregister the se_tpg from TCM.
 	 */
 	core_tpg_deregister(se_tpg);
 	kfree(tpg);
···
 	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
···
 	 * 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;
 };
 
···
 
 	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[] = {
···
 	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;
 }
 

drivers/xen/xenbus/xenbus_client.c

···
 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);
 };
 
···
 /**
  * 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);
···
 /**
  * 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);
 
-static int xenbus_map_ring_valloc_pv(struct xenbus_device *dev,
-				     int gnt_ref, void **vaddr)
+/* 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 op = {
-		.flags = GNTMAP_host_map | GNTMAP_contains_pte,
-		.ref   = gnt_ref,
-		.dom   = dev->otherend_id,
-	};
+	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,
+				     grant_ref_t *gnt_refs,
+				     unsigned int nr_grefs,
+				     void **vaddr)
+{
 	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);
+	err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
+				phys_addrs,
+				GNTMAP_host_map | GNTMAP_contains_pte,
+				&leaked);
+	if (err)
+		goto failed;
 
-	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;
-	}
-
-	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);
···
 
 	*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;
 
···
 	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, &node->handle, addr);
+	err = __xenbus_map_ring(dev, gnt_ref, nr_grefs, node->handles,
+				phys_addrs, GNTMAP_host_map, &leaked);
+	node->nr_handles = nr_grefs;
+
 	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);
···
 	*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;
···
 /**
  * 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;
+	phys_addr_t phys_addrs[XENBUS_MAX_RING_PAGES];
+	int i;
 
-	gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref,
-			  dev->otherend_id);
+	if (nr_grefs > XENBUS_MAX_RING_PAGES)
+		return -EINVAL;
 
-	gnttab_batch_map(&op, 1);
+	for (i = 0; i < nr_grefs; i++)
+		phys_addrs[i] = (unsigned long)vaddrs[i];
 
-	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;
-
-	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);
 
···
 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;
 		}
···
 		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;
 
-	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+		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, 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)
···
 	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;
···
 		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;
···
 /**
  * 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);
 

drivers/xen/xlate_mmu.c

···
+/*
+ * 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);

include/xen/interface/xen.h

···
 #define __HYPERVISOR_vcpu_op              24
 #define __HYPERVISOR_set_segment_base     25 /* x86/64 only */
 #define __HYPERVISOR_mmuext_op            26
-#define __HYPERVISOR_acm_op               27
+#define __HYPERVISOR_xsm_op               27
 #define __HYPERVISOR_nmi_op               28
 #define __HYPERVISOR_sched_op             29
 #define __HYPERVISOR_callback_op          30
···
 #define __HYPERVISOR_event_channel_op     32
 #define __HYPERVISOR_physdev_op           33
 #define __HYPERVISOR_hvm_op               34
+#define __HYPERVISOR_sysctl               35
+#define __HYPERVISOR_domctl               36
+#define __HYPERVISOR_kexec_op             37
 #define __HYPERVISOR_tmem_op              38
+#define __HYPERVISOR_xc_reserved_op       39 /* reserved for XenClient */
 
 /* Architecture-specific hypercall definitions. */
 #define __HYPERVISOR_arch_0               48

include/xen/xen-ops.h

···
 void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order);
 
 struct vm_area_struct;
+
+/*
+ * xen_remap_domain_mfn_array() - map an array of foreign frames
+ * @vma:     VMA to map the pages into
+ * @addr:    Address at which to map the pages
+ * @gfn:     Array of GFNs to map
+ * @nr:      Number entries in the GFN array
+ * @err_ptr: Returns per-GFN error status.
+ * @prot:    page protection mask
+ * @domid:   Domain owning the pages
+ * @pages:   Array of pages if this domain has an auto-translated physmap
+ *
+ * @gfn and @err_ptr may point to the same buffer, the GFNs will be
+ * overwritten by the error codes after they are mapped.
+ *
+ * Returns the number of successfully mapped frames, or a -ve error
+ * code.
+ */
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+			       unsigned long addr,
+			       xen_pfn_t *gfn, int nr,
+			       int *err_ptr, pgprot_t prot,
+			       unsigned domid,
+			       struct page **pages);
+
+/* xen_remap_domain_mfn_range() - map a range of foreign frames
+ * @vma:     VMA to map the pages into
+ * @addr:    Address at which to map the pages
+ * @gfn:     First GFN to map.
+ * @nr:      Number frames to map
+ * @prot:    page protection mask
+ * @domid:   Domain owning the pages
+ * @pages:   Array of pages if this domain has an auto-translated physmap
+ *
+ * Returns the number of successfully mapped frames, or a -ve error
+ * code.
+ */
 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
 			       unsigned long addr,
-			       xen_pfn_t mfn, int nr,
+			       xen_pfn_t gfn, int nr,
 			       pgprot_t prot, unsigned domid,
 			       struct page **pages);
 int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
 			       int numpgs, struct page **pages);
+int xen_xlate_remap_gfn_array(struct vm_area_struct *vma,
+			      unsigned long addr,
+			      xen_pfn_t *gfn, int nr,
+			      int *err_ptr, pgprot_t prot,
+			      unsigned domid,
+			      struct page **pages);
+int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma,
+			      int nr, struct page **pages);
 
 bool xen_running_on_version_or_later(unsigned int major, unsigned int minor);
 

include/xen/xenbus.h

···
 #include <xen/interface/io/xenbus.h>
 #include <xen/interface/io/xs_wire.h>
 
+#define XENBUS_MAX_RING_PAGE_ORDER 4
+#define XENBUS_MAX_RING_PAGES      (1U << XENBUS_MAX_RING_PAGE_ORDER)
+#define INVALID_GRANT_HANDLE       (~0U)
+
 /* Register callback to watch this node. */
 struct xenbus_watch
 {
···
 			 const char *pathfmt, ...);
 
 int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state);
-int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn);
-int xenbus_map_ring_valloc(struct xenbus_device *dev,
-			   int gnt_ref, void **vaddr);
-int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
-			   grant_handle_t *handle, void *vaddr);
+int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
+		      unsigned int nr_pages, grant_ref_t *grefs);
+int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
+			   unsigned int nr_grefs, 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);
 
 int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
 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);
 
 int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
 int xenbus_free_evtchn(struct xenbus_device *dev, int port);

scripts/xen-hypercalls.sh

···
+#!/bin/sh
+out="$1"
+shift
+in="$@"
+
+for i in $in; do
+	eval $CPP $LINUXINCLUDE -dD -imacros "$i" -x c /dev/null
+done | \
+awk '$1 == "#define" && $2 ~ /__HYPERVISOR_[a-z][a-z_0-9]*/ { v[$3] = $2 }
+	END {   print "/* auto-generated by scripts/xen-hypercall.sh */"
+		for (i in v) if (!(v[i] in v))
+			print "HYPERCALL("substr(v[i], 14)")"}' | sort -u >$out