Merge tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from David Vrabel:
 - remove unused V2 grant table support
 - note that Konrad is xen-blkkback/front maintainer
 - add 'xen_nopv' option to disable PV extentions for x86 HVM guests
 - misc minor cleanups

* tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-pciback: Document the 'quirks' sysfs file
  xen/pciback: Fix error return code in xen_pcibk_attach()
  xen/events: drop negativity check of unsigned parameter
  xen/setup: Remove Identity Map Debug Message
  xen/events/fifo: remove a unecessary use of BM()
  xen/events/fifo: ensure all bitops are properly aligned even on x86
  xen/events/fifo: reset control block and local HEADs on resume
  xen/arm: use BUG_ON
  xen/grant-table: remove support for V2 tables
  x86/xen: safely map and unmap grant frames when in atomic context
  MAINTAINERS: Make me the Xen block subsystem (front and back) maintainer
  xen: Introduce 'xen_nopv' to disable PV extensions for HVM guests.

13 files changed, 88 insertions, 423 deletions

diff --git a/Documentation/ABI/testing/sysfs-driver-pciback b/Documentation/ABI/testing/sysfs-driver-pciback
new file mode 100644
index 000000000000..6a733bfa37e6
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-pciback
@@ -0,0 +1,13 @@
+What:           /sys/bus/pci/drivers/pciback/quirks
+Date:           Oct 2011
+KernelVersion:  3.1
+Contact:        xen-devel@lists.xenproject.org
+Description:
+                If the permissive attribute is set, then writing a string in
+                the format of DDDD:BB:DD.F-REG:SIZE:MASK will allow the guest
+                to write and read from the PCI device. That is Domain:Bus:
+                Device.Function-Register:Size:Mask (Domain is optional).
+                For example:
+                #echo 00:19.0-E0:2:FF > /sys/bus/pci/drivers/pciback/quirks
+                will allow the guest to read and write to the configuration
+                register 0x0E.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 664fd887cc37..a8eb6afce6a4 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3745,6 +3745,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         Disables the ticketlock slowpath using Xen PV
                         optimizations.
 
+        xen_nopv        [X86]
+                        Disables the PV optimizations forcing the HVM guest to
+                        run as generic HVM guest with no PV drivers.
+
         xirc2ps_cs=     [NET,PCMCIA]
                         Format:
                         <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
diff --git a/MAINTAINERS b/MAINTAINERS
index 946a67e6c4ea..b0981c2f4218 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10066,6 +10066,13 @@ S:	Supported
 F:      arch/x86/pci/*xen*
 F:      drivers/pci/*xen*
 
+XEN BLOCK SUBSYSTEM
+M:      Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+L:      xen-devel@lists.xenproject.org (moderated for non-subscribers)
+S:      Supported
+F:      drivers/block/xen-blkback/*
+F:      drivers/block/xen*
+
 XEN SWIOTLB SUBSYSTEM
 M:      Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
 L:      xen-devel@lists.xenproject.org (moderated for non-subscribers)
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 1e632430570b..98544c5f86e9 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -181,8 +181,7 @@ static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
         struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
         int rc;
         rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
-        if (rc)
-                BUG();
+        BUG_ON(rc);
 }
 
 static void xen_power_off(void)
@@ -190,8 +189,7 @@ static void xen_power_off(void)
         struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
         int rc;
         rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
-        if (rc)
-                BUG();
+        BUG_ON(rc);
 }
 
 static int xen_cpu_notification(struct notifier_block *self,
diff --git a/arch/arm/xen/grant-table.c b/arch/arm/xen/grant-table.c
index 91cf08ba1e95..2c4041c9bac5 100644
--- a/arch/arm/xen/grant-table.c
+++ b/arch/arm/xen/grant-table.c
@@ -45,11 +45,9 @@ void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
         return;
 }
 
-int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
-                           unsigned long max_nr_gframes,
-                           grant_status_t **__shared)
+int arch_gnttab_init(unsigned long nr_shared)
 {
-        return -ENOSYS;
+        return 0;
 }
 
 int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 94813515fdd6..c0cb11fb5008 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1828,8 +1828,19 @@ static void __init xen_hvm_guest_init(void)
         xen_hvm_init_mmu_ops();
 }
 
+static bool xen_nopv = false;
+static __init int xen_parse_nopv(char *arg)
+{
+       xen_nopv = true;
+       return 0;
+}
+early_param("xen_nopv", xen_parse_nopv);
+
 static uint32_t __init xen_hvm_platform(void)
 {
+        if (xen_nopv)
+                return 0;
+
         if (xen_pv_domain())
                 return 0;
 
@@ -1838,6 +1849,8 @@ static uint32_t __init xen_hvm_platform(void)
 
 bool xen_hvm_need_lapic(void)
 {
+        if (xen_nopv)
+                return false;
         if (xen_pv_domain())
                 return false;
         if (!xen_hvm_domain())
diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index ebfa9b2c871d..c0413046483a 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -49,7 +49,7 @@
 static struct gnttab_vm_area {
         struct vm_struct *area;
         pte_t **ptes;
-} gnttab_shared_vm_area, gnttab_status_vm_area;
+} gnttab_shared_vm_area;
 
 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
                            unsigned long max_nr_gframes,
@@ -73,43 +73,16 @@ int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
         return 0;
 }
 
-int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
-                           unsigned long max_nr_gframes,
-                           grant_status_t **__shared)
-{
-        grant_status_t *shared = *__shared;
-        unsigned long addr;
-        unsigned long i;
-
-        if (shared == NULL)
-                *__shared = shared = gnttab_status_vm_area.area->addr;
-
-        addr = (unsigned long)shared;
-
-        for (i = 0; i < nr_gframes; i++) {
-                set_pte_at(&init_mm, addr, gnttab_status_vm_area.ptes[i],
-                           mfn_pte(frames[i], PAGE_KERNEL));
-                addr += PAGE_SIZE;
-        }
-
-        return 0;
-}
-
 void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
 {
-        pte_t **ptes;
         unsigned long addr;
         unsigned long i;
 
-        if (shared == gnttab_status_vm_area.area->addr)
-                ptes = gnttab_status_vm_area.ptes;
-        else
-                ptes = gnttab_shared_vm_area.ptes;
-
         addr = (unsigned long)shared;
 
         for (i = 0; i < nr_gframes; i++) {
-                set_pte_at(&init_mm, addr, ptes[i], __pte(0));
+                set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
+                           __pte(0));
                 addr += PAGE_SIZE;
         }
 }
@@ -129,35 +102,12 @@ static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
         return 0;
 }
 
-static void arch_gnttab_vfree(struct gnttab_vm_area *area)
+int arch_gnttab_init(unsigned long nr_shared)
 {
-        free_vm_area(area->area);
-        kfree(area->ptes);
-}
-
-int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
-{
-        int ret;
-
         if (!xen_pv_domain())
                 return 0;
 
-        ret = arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
-        if (ret < 0)
-                return ret;
-
-        /*
-         * Always allocate the space for the status frames in case
-         * we're migrated to a host with V2 support.
-         */
-        ret = arch_gnttab_valloc(&gnttab_status_vm_area, nr_status);
-        if (ret < 0)
-                goto err;
-
-        return 0;
-  err:
-        arch_gnttab_vfree(&gnttab_shared_vm_area);
-        return -ENOMEM;
+        return arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
 }
 
 #ifdef CONFIG_XEN_PVH
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index 9bb3d82ffec8..3172692381ae 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -841,10 +841,9 @@ unsigned long __init set_phys_range_identity(unsigned long pfn_s,
                         pfn = ALIGN(pfn, P2M_PER_PAGE);
         }
 
-        if (!WARN((pfn - pfn_s) != (pfn_e - pfn_s),
+        WARN((pfn - pfn_s) != (pfn_e - pfn_s),
                 "Identity mapping failed. We are %ld short of 1-1 mappings!\n",
-                (pfn_e - pfn_s) - (pfn - pfn_s)))
-                printk(KERN_DEBUG "1-1 mapping on %lx->%lx\n", pfn_s, pfn);
+                (pfn_e - pfn_s) - (pfn - pfn_s));
 
         return pfn - pfn_s;
 }
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index c919d3d5c845..5b5c5ff273fd 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -246,7 +246,7 @@ static void xen_irq_info_cleanup(struct irq_info *info)
  */
 unsigned int evtchn_from_irq(unsigned irq)
 {
-        if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
+        if (unlikely(WARN(irq >= nr_irqs, "Invalid irq %d!\n", irq)))
                 return 0;
 
         return info_for_irq(irq)->evtchn;
diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c
index 84b4bfb84344..417415d738d0 100644
--- a/drivers/xen/events/events_fifo.c
+++ b/drivers/xen/events/events_fifo.c
@@ -67,10 +67,9 @@ static event_word_t *event_array[MAX_EVENT_ARRAY_PAGES] __read_mostly;
 static unsigned event_array_pages __read_mostly;
 
 /*
- * sync_set_bit() and friends must be unsigned long aligned on non-x86
- * platforms.
+ * sync_set_bit() and friends must be unsigned long aligned.
  */
-#if !defined(CONFIG_X86) && BITS_PER_LONG > 32
+#if BITS_PER_LONG > 32
 
 #define BM(w) (unsigned long *)((unsigned long)w & ~0x7UL)
 #define EVTCHN_FIFO_BIT(b, w) \
@@ -100,6 +99,25 @@ static unsigned evtchn_fifo_nr_channels(void)
         return event_array_pages * EVENT_WORDS_PER_PAGE;
 }
 
+static int init_control_block(int cpu,
+                              struct evtchn_fifo_control_block *control_block)
+{
+        struct evtchn_fifo_queue *q = &per_cpu(cpu_queue, cpu);
+        struct evtchn_init_control init_control;
+        unsigned int i;
+
+        /* Reset the control block and the local HEADs. */
+        clear_page(control_block);
+        for (i = 0; i < EVTCHN_FIFO_MAX_QUEUES; i++)
+                q->head[i] = 0;
+
+        init_control.control_gfn = virt_to_mfn(control_block);
+        init_control.offset      = 0;
+        init_control.vcpu        = cpu;
+
+        return HYPERVISOR_event_channel_op(EVTCHNOP_init_control, &init_control);
+}
+
 static void free_unused_array_pages(void)
 {
         unsigned i;
@@ -312,7 +330,7 @@ static void evtchn_fifo_handle_events(unsigned cpu)
         ready = xchg(&control_block->ready, 0);
 
         while (ready) {
-                q = find_first_bit(BM(&ready), EVTCHN_FIFO_MAX_QUEUES);
+                q = find_first_bit(&ready, EVTCHN_FIFO_MAX_QUEUES);
                 consume_one_event(cpu, control_block, q, &ready);
                 ready |= xchg(&control_block->ready, 0);
         }
@@ -324,7 +342,6 @@ static void evtchn_fifo_resume(void)
 
         for_each_possible_cpu(cpu) {
                 void *control_block = per_cpu(cpu_control_block, cpu);
-                struct evtchn_init_control init_control;
                 int ret;
 
                 if (!control_block)
@@ -341,12 +358,7 @@ static void evtchn_fifo_resume(void)
                         continue;
                 }
 
-                init_control.control_gfn = virt_to_mfn(control_block);
-                init_control.offset = 0;
-                init_control.vcpu = cpu;
-
-                ret = HYPERVISOR_event_channel_op(EVTCHNOP_init_control,
-                                                  &init_control);
+                ret = init_control_block(cpu, control_block);
                 if (ret < 0)
                         BUG();
         }
@@ -374,30 +386,25 @@ static const struct evtchn_ops evtchn_ops_fifo = {
         .resume            = evtchn_fifo_resume,
 };
 
-static int evtchn_fifo_init_control_block(unsigned cpu)
+static int evtchn_fifo_alloc_control_block(unsigned cpu)
 {
-        struct page *control_block = NULL;
-        struct evtchn_init_control init_control;
+        void *control_block = NULL;
         int ret = -ENOMEM;
 
-        control_block = alloc_page(GFP_KERNEL|__GFP_ZERO);
+        control_block = (void *)__get_free_page(GFP_KERNEL);
         if (control_block == NULL)
                 goto error;
 
-        init_control.control_gfn = virt_to_mfn(page_address(control_block));
-        init_control.offset      = 0;
-        init_control.vcpu        = cpu;
-
-        ret = HYPERVISOR_event_channel_op(EVTCHNOP_init_control, &init_control);
+        ret = init_control_block(cpu, control_block);
         if (ret < 0)
                 goto error;
 
-        per_cpu(cpu_control_block, cpu) = page_address(control_block);
+        per_cpu(cpu_control_block, cpu) = control_block;
 
         return 0;
 
   error:
-        __free_page(control_block);
+        free_page((unsigned long)control_block);
         return ret;
 }
 
@@ -411,7 +418,7 @@ static int evtchn_fifo_cpu_notification(struct notifier_block *self,
         switch (action) {
         case CPU_UP_PREPARE:
                 if (!per_cpu(cpu_control_block, cpu))
-                        ret = evtchn_fifo_init_control_block(cpu);
+                        ret = evtchn_fifo_alloc_control_block(cpu);
                 break;
         default:
                 break;
@@ -428,7 +435,7 @@ int __init xen_evtchn_fifo_init(void)
         int cpu = get_cpu();
         int ret;
 
-        ret = evtchn_fifo_init_control_block(cpu);
+        ret = evtchn_fifo_alloc_control_block(cpu);
         if (ret < 0)
                 goto out;
 
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index eeba7544f0cd..c254ae036f18 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -69,7 +69,6 @@ struct grant_frames xen_auto_xlat_grant_frames;
 
 static union {
         struct grant_entry_v1 *v1;
-        union grant_entry_v2 *v2;
         void *addr;
 } gnttab_shared;
 
@@ -120,36 +119,10 @@ struct gnttab_ops {
          * by bit operations.
          */
         int (*query_foreign_access)(grant_ref_t ref);
-        /*
-         * Grant a domain to access a range of bytes within the page referred by
-         * an available grant entry. Ref parameter is reference of a grant entry
-         * which will be sub-page accessed, domid is id of grantee domain, frame
-         * is frame address of subpage grant, flags is grant type and flag
-         * information, page_off is offset of the range of bytes, and length is
-         * length of bytes to be accessed.
-         */
-        void (*update_subpage_entry)(grant_ref_t ref, domid_t domid,
-                                     unsigned long frame, int flags,
-                                     unsigned page_off, unsigned length);
-        /*
-         * Redirect an available grant entry on domain A to another grant
-         * reference of domain B, then allow domain C to use grant reference
-         * of domain B transitively. Ref parameter is an available grant entry
-         * reference on domain A, domid is id of domain C which accesses grant
-         * entry transitively, flags is grant type and flag information,
-         * trans_domid is id of domain B whose grant entry is finally accessed
-         * transitively, trans_gref is grant entry transitive reference of
-         * domain B.
-         */
-        void (*update_trans_entry)(grant_ref_t ref, domid_t domid, int flags,
-                                   domid_t trans_domid, grant_ref_t trans_gref);
 };
 
 static struct gnttab_ops *gnttab_interface;
 
-/*This reflects status of grant entries, so act as a global value*/
-static grant_status_t *grstatus;
-
 static int grant_table_version;
 static int grefs_per_grant_frame;
 
@@ -231,7 +204,7 @@ static void put_free_entry(grant_ref_t ref)
 }
 
 /*
- * Following applies to gnttab_update_entry_v1 and gnttab_update_entry_v2.
+ * Following applies to gnttab_update_entry_v1.
  * Introducing a valid entry into the grant table:
  *  1. Write ent->domid.
  *  2. Write ent->frame:
@@ -250,15 +223,6 @@ static void gnttab_update_entry_v1(grant_ref_t ref, domid_t domid,
         gnttab_shared.v1[ref].flags = flags;
 }
 
-static void gnttab_update_entry_v2(grant_ref_t ref, domid_t domid,
-                                   unsigned long frame, unsigned flags)
-{
-        gnttab_shared.v2[ref].hdr.domid = domid;
-        gnttab_shared.v2[ref].full_page.frame = frame;
-        wmb();
-        gnttab_shared.v2[ref].hdr.flags = GTF_permit_access | flags;
-}
-
 /*
  * Public grant-issuing interface functions
  */
@@ -285,132 +249,11 @@ int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
 }
 EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);
 
-static void gnttab_update_subpage_entry_v2(grant_ref_t ref, domid_t domid,
-                                           unsigned long frame, int flags,
-                                           unsigned page_off, unsigned length)
-{
-        gnttab_shared.v2[ref].sub_page.frame = frame;
-        gnttab_shared.v2[ref].sub_page.page_off = page_off;
-        gnttab_shared.v2[ref].sub_page.length = length;
-        gnttab_shared.v2[ref].hdr.domid = domid;
-        wmb();
-        gnttab_shared.v2[ref].hdr.flags =
-                                GTF_permit_access | GTF_sub_page | flags;
-}
-
-int gnttab_grant_foreign_access_subpage_ref(grant_ref_t ref, domid_t domid,
-                                            unsigned long frame, int flags,
-                                            unsigned page_off,
-                                            unsigned length)
-{
-        if (flags & (GTF_accept_transfer | GTF_reading |
-                     GTF_writing | GTF_transitive))
-                return -EPERM;
-
-        if (gnttab_interface->update_subpage_entry == NULL)
-                return -ENOSYS;
-
-        gnttab_interface->update_subpage_entry(ref, domid, frame, flags,
-                                               page_off, length);
-
-        return 0;
-}
-EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_subpage_ref);
-
-int gnttab_grant_foreign_access_subpage(domid_t domid, unsigned long frame,
-                                        int flags, unsigned page_off,
-                                        unsigned length)
-{
-        int ref, rc;
-
-        ref = get_free_entries(1);
-        if (unlikely(ref < 0))
-                return -ENOSPC;
-
-        rc = gnttab_grant_foreign_access_subpage_ref(ref, domid, frame, flags,
-                                                     page_off, length);
-        if (rc < 0) {
-                put_free_entry(ref);
-                return rc;
-        }
-
-        return ref;
-}
-EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_subpage);
-
-bool gnttab_subpage_grants_available(void)
-{
-        return gnttab_interface->update_subpage_entry != NULL;
-}
-EXPORT_SYMBOL_GPL(gnttab_subpage_grants_available);
-
-static void gnttab_update_trans_entry_v2(grant_ref_t ref, domid_t domid,
-                                         int flags, domid_t trans_domid,
-                                         grant_ref_t trans_gref)
-{
-        gnttab_shared.v2[ref].transitive.trans_domid = trans_domid;
-        gnttab_shared.v2[ref].transitive.gref = trans_gref;
-        gnttab_shared.v2[ref].hdr.domid = domid;
-        wmb();
-        gnttab_shared.v2[ref].hdr.flags =
-                                GTF_permit_access | GTF_transitive | flags;
-}
-
-int gnttab_grant_foreign_access_trans_ref(grant_ref_t ref, domid_t domid,
-                                          int flags, domid_t trans_domid,
-                                          grant_ref_t trans_gref)
-{
-        if (flags & (GTF_accept_transfer | GTF_reading |
-                     GTF_writing | GTF_sub_page))
-                return -EPERM;
-
-        if (gnttab_interface->update_trans_entry == NULL)
-                return -ENOSYS;
-
-        gnttab_interface->update_trans_entry(ref, domid, flags, trans_domid,
-                                             trans_gref);
-
-        return 0;
-}
-EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_trans_ref);
-
-int gnttab_grant_foreign_access_trans(domid_t domid, int flags,
-                                      domid_t trans_domid,
-                                      grant_ref_t trans_gref)
-{
-        int ref, rc;
-
-        ref = get_free_entries(1);
-        if (unlikely(ref < 0))
-                return -ENOSPC;
-
-        rc = gnttab_grant_foreign_access_trans_ref(ref, domid, flags,
-                                                   trans_domid, trans_gref);
-        if (rc < 0) {
-                put_free_entry(ref);
-                return rc;
-        }
-
-        return ref;
-}
-EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_trans);
-
-bool gnttab_trans_grants_available(void)
-{
-        return gnttab_interface->update_trans_entry != NULL;
-}
-EXPORT_SYMBOL_GPL(gnttab_trans_grants_available);
-
 static int gnttab_query_foreign_access_v1(grant_ref_t ref)
 {
         return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing);
 }
 
-static int gnttab_query_foreign_access_v2(grant_ref_t ref)
-{
-        return grstatus[ref] & (GTF_reading|GTF_writing);
-}
-
 int gnttab_query_foreign_access(grant_ref_t ref)
 {
         return gnttab_interface->query_foreign_access(ref);
@@ -433,29 +276,6 @@ static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
         return 1;
 }
 
-static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly)
-{
-        gnttab_shared.v2[ref].hdr.flags = 0;
-        mb();
-        if (grstatus[ref] & (GTF_reading|GTF_writing)) {
-                return 0;
-        } else {
-                /* The read of grstatus needs to have acquire
-                semantics.  On x86, reads already have
-                that, and we just need to protect against
-                compiler reorderings.  On other
-                architectures we may need a full
-                barrier. */
-#ifdef CONFIG_X86
-                barrier();
-#else
-                mb();
-#endif
-        }
-
-        return 1;
-}
-
 static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
 {
         return gnttab_interface->end_foreign_access_ref(ref, readonly);
@@ -616,37 +436,6 @@ static unsigned long gnttab_end_foreign_transfer_ref_v1(grant_ref_t ref)
         return frame;
 }
 
-static unsigned long gnttab_end_foreign_transfer_ref_v2(grant_ref_t ref)
-{
-        unsigned long frame;
-        u16           flags;
-        u16          *pflags;
-
-        pflags = &gnttab_shared.v2[ref].hdr.flags;
-
-        /*
-         * If a transfer is not even yet started, try to reclaim the grant
-         * reference and return failure (== 0).
-         */
-        while (!((flags = *pflags) & GTF_transfer_committed)) {
-                if (sync_cmpxchg(pflags, flags, 0) == flags)
-                        return 0;
-                cpu_relax();
-        }
-
-        /* If a transfer is in progress then wait until it is completed. */
-        while (!(flags & GTF_transfer_completed)) {
-                flags = *pflags;
-                cpu_relax();
-        }
-
-        rmb();  /* Read the frame number /after/ reading completion status. */
-        frame = gnttab_shared.v2[ref].full_page.frame;
-        BUG_ON(frame == 0);
-
-        return frame;
-}
-
 unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref)
 {
         return gnttab_interface->end_foreign_transfer_ref(ref);
@@ -962,12 +751,6 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
 }
 EXPORT_SYMBOL_GPL(gnttab_unmap_refs);
 
-static unsigned nr_status_frames(unsigned nr_grant_frames)
-{
-        BUG_ON(grefs_per_grant_frame == 0);
-        return (nr_grant_frames * grefs_per_grant_frame + SPP - 1) / SPP;
-}
-
 static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes)
 {
         int rc;
@@ -985,55 +768,6 @@ static void gnttab_unmap_frames_v1(void)
         arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames);
 }
 
-static int gnttab_map_frames_v2(xen_pfn_t *frames, unsigned int nr_gframes)
-{
-        uint64_t *sframes;
-        unsigned int nr_sframes;
-        struct gnttab_get_status_frames getframes;
-        int rc;
-
-        nr_sframes = nr_status_frames(nr_gframes);
-
-        /* No need for kzalloc as it is initialized in following hypercall
-         * GNTTABOP_get_status_frames.
-         */
-        sframes = kmalloc(nr_sframes  * sizeof(uint64_t), GFP_ATOMIC);
-        if (!sframes)
-                return -ENOMEM;
-
-        getframes.dom        = DOMID_SELF;
-        getframes.nr_frames  = nr_sframes;
-        set_xen_guest_handle(getframes.frame_list, sframes);
-
-        rc = HYPERVISOR_grant_table_op(GNTTABOP_get_status_frames,
-                                       &getframes, 1);
-        if (rc == -ENOSYS) {
-                kfree(sframes);
-                return -ENOSYS;
-        }
-
-        BUG_ON(rc || getframes.status);
-
-        rc = arch_gnttab_map_status(sframes, nr_sframes,
-                                    nr_status_frames(gnttab_max_grant_frames()),
-                                    &grstatus);
-        BUG_ON(rc);
-        kfree(sframes);
-
-        rc = arch_gnttab_map_shared(frames, nr_gframes,
-                                    gnttab_max_grant_frames(),
-                                    &gnttab_shared.addr);
-        BUG_ON(rc);
-
-        return 0;
-}
-
-static void gnttab_unmap_frames_v2(void)
-{
-        arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames);
-        arch_gnttab_unmap(grstatus, nr_status_frames(nr_grant_frames));
-}
-
 static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
 {
         struct gnttab_setup_table setup;
@@ -1101,43 +835,13 @@ static struct gnttab_ops gnttab_v1_ops = {
         .query_foreign_access           = gnttab_query_foreign_access_v1,
 };
 
-static struct gnttab_ops gnttab_v2_ops = {
-        .map_frames                     = gnttab_map_frames_v2,
-        .unmap_frames                   = gnttab_unmap_frames_v2,
-        .update_entry                   = gnttab_update_entry_v2,
-        .end_foreign_access_ref         = gnttab_end_foreign_access_ref_v2,
-        .end_foreign_transfer_ref       = gnttab_end_foreign_transfer_ref_v2,
-        .query_foreign_access           = gnttab_query_foreign_access_v2,
-        .update_subpage_entry           = gnttab_update_subpage_entry_v2,
-        .update_trans_entry             = gnttab_update_trans_entry_v2,
-};
-
 static void gnttab_request_version(void)
 {
-        int rc;
-        struct gnttab_set_version gsv;
+        /* Only version 1 is used, which will always be available. */
+        grant_table_version = 1;
+        grefs_per_grant_frame = PAGE_SIZE / sizeof(struct grant_entry_v1);
+        gnttab_interface = &gnttab_v1_ops;
 
-        gsv.version = 1;
-
-        rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1);
-        if (rc == 0 && gsv.version == 2) {
-                grant_table_version = 2;
-                grefs_per_grant_frame = PAGE_SIZE / sizeof(union grant_entry_v2);
-                gnttab_interface = &gnttab_v2_ops;
-        } else if (grant_table_version == 2) {
-                /*
-                 * If we've already used version 2 features,
-                 * but then suddenly discover that they're not
-                 * available (e.g. migrating to an older
-                 * version of Xen), almost unbounded badness
-                 * can happen.
-                 */
-                panic("we need grant tables version 2, but only version 1 is available");
-        } else {
-                grant_table_version = 1;
-                grefs_per_grant_frame = PAGE_SIZE / sizeof(struct grant_entry_v1);
-                gnttab_interface = &gnttab_v1_ops;
-        }
         pr_info("Grant tables using version %d layout\n", grant_table_version);
 }
 
@@ -1225,8 +929,7 @@ int gnttab_init(void)
                 }
         }
 
-        ret = arch_gnttab_init(max_nr_grant_frames,
-                               nr_status_frames(max_nr_grant_frames));
+        ret = arch_gnttab_init(max_nr_grant_frames);
         if (ret < 0)
                 goto ini_nomem;
 
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index 4a7e6e0a5f4c..c214daab4829 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -174,6 +174,7 @@ static int xen_pcibk_attach(struct xen_pcibk_device *pdev)
                                  "version mismatch (%s/%s) with pcifront - "
                                  "halting " DRV_NAME,
                                  magic, XEN_PCI_MAGIC);
+                err = -EFAULT;
                 goto out;
         }
 
diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h
index 5c1aba154b64..3387465b9caa 100644
--- a/include/xen/grant_table.h
+++ b/include/xen/grant_table.h
@@ -64,24 +64,6 @@ int gnttab_resume(void);
 
 int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
                                 int readonly);
-int gnttab_grant_foreign_access_subpage(domid_t domid, unsigned long frame,
-                                        int flags, unsigned page_off,
-                                        unsigned length);
-int gnttab_grant_foreign_access_trans(domid_t domid, int flags,
-                                      domid_t trans_domid,
-                                      grant_ref_t trans_gref);
-
-/*
- * Are sub-page grants available on this version of Xen?  Returns true if they
- * are, and false if they're not.
- */
-bool gnttab_subpage_grants_available(void);
-
-/*
- * Are transitive grants available on this version of Xen?  Returns true if they
- * are, and false if they're not.
- */
-bool gnttab_trans_grants_available(void);
 
 /*
  * End access through the given grant reference, iff the grant entry is no
@@ -128,13 +110,6 @@ void gnttab_cancel_free_callback(struct gnttab_free_callback *callback);
 
 void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
                                      unsigned long frame, int readonly);
-int gnttab_grant_foreign_access_subpage_ref(grant_ref_t ref, domid_t domid,
-                                            unsigned long frame, int flags,
-                                            unsigned page_off,
-                                            unsigned length);
-int gnttab_grant_foreign_access_trans_ref(grant_ref_t ref, domid_t domid,
-                                          int flags, domid_t trans_domid,
-                                          grant_ref_t trans_gref);
 
 void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
                                        unsigned long pfn);
@@ -170,13 +145,10 @@ gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
         unmap->dev_bus_addr = 0;
 }
 
-int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status);
+int arch_gnttab_init(unsigned long nr_shared);
 int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes,
                            unsigned long max_nr_gframes,
                            void **__shared);
-int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
-                           unsigned long max_nr_gframes,
-                           grant_status_t **__shared);
 void arch_gnttab_unmap(void *shared, unsigned long nr_gframes);
 
 struct grant_frames {