8 files changed, 115 insertions, 28 deletions

diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 3ee2b91ca4e..fb213cf81a7 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -2,6 +2,7 @@ ifneq ($(CONFIG_ARM),y)
 obj-y   += manage.o
 obj-$(CONFIG_HOTPLUG_CPU)               += cpu_hotplug.o
 endif
+obj-$(CONFIG_X86)                       += fallback.o
 obj-y   += grant-table.o features.o events.o balloon.o
 obj-y   += xenbus/
 
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 912ac81b6db..0be4df39e95 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -1395,10 +1395,10 @@ void xen_evtchn_do_upcall(struct pt_regs *regs)
 {
         struct pt_regs *old_regs = set_irq_regs(regs);
 
+        irq_enter();
 #ifdef CONFIG_X86
         exit_idle();
 #endif
-        irq_enter();
 
         __xen_evtchn_do_upcall();
 
diff --git a/drivers/xen/fallback.c b/drivers/xen/fallback.c
new file mode 100644
index 00000000000..0ef7c4d40f8
--- /dev/null
+++ b/drivers/xen/fallback.c
@@ -0,0 +1,80 @@
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/bug.h>
+#include <linux/export.h>
+#include <asm/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+int xen_event_channel_op_compat(int cmd, void *arg)
+{
+        struct evtchn_op op;
+        int rc;
+
+        op.cmd = cmd;
+        memcpy(&op.u, arg, sizeof(op.u));
+        rc = _hypercall1(int, event_channel_op_compat, &op);
+
+        switch (cmd) {
+        case EVTCHNOP_close:
+        case EVTCHNOP_send:
+        case EVTCHNOP_bind_vcpu:
+        case EVTCHNOP_unmask:
+                /* no output */
+                break;
+
+#define COPY_BACK(eop) \
+        case EVTCHNOP_##eop: \
+                memcpy(arg, &op.u.eop, sizeof(op.u.eop)); \
+                break
+
+        COPY_BACK(bind_interdomain);
+        COPY_BACK(bind_virq);
+        COPY_BACK(bind_pirq);
+        COPY_BACK(status);
+        COPY_BACK(alloc_unbound);
+        COPY_BACK(bind_ipi);
+#undef COPY_BACK
+
+        default:
+                WARN_ON(rc != -ENOSYS);
+                break;
+        }
+
+        return rc;
+}
+EXPORT_SYMBOL_GPL(xen_event_channel_op_compat);
+
+int HYPERVISOR_physdev_op_compat(int cmd, void *arg)
+{
+        struct physdev_op op;
+        int rc;
+
+        op.cmd = cmd;
+        memcpy(&op.u, arg, sizeof(op.u));
+        rc = _hypercall1(int, physdev_op_compat, &op);
+
+        switch (cmd) {
+        case PHYSDEVOP_IRQ_UNMASK_NOTIFY:
+        case PHYSDEVOP_set_iopl:
+        case PHYSDEVOP_set_iobitmap:
+        case PHYSDEVOP_apic_write:
+                /* no output */
+                break;
+
+#define COPY_BACK(pop, fld) \
+        case PHYSDEVOP_##pop: \
+                memcpy(arg, &op.u.fld, sizeof(op.u.fld)); \
+                break
+
+        COPY_BACK(irq_status_query, irq_status_query);
+        COPY_BACK(apic_read, apic_op);
+        COPY_BACK(ASSIGN_VECTOR, irq_op);
+#undef COPY_BACK
+
+        default:
+                WARN_ON(rc != -ENOSYS);
+                break;
+        }
+
+        return rc;
+}
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 610bfc6be17..2e22df2f7a3 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -105,6 +105,21 @@ static void gntdev_print_maps(struct gntdev_priv *priv,
 #endif
 }
 
+static void gntdev_free_map(struct grant_map *map)
+{
+        if (map == NULL)
+                return;
+
+        if (map->pages)
+                free_xenballooned_pages(map->count, map->pages);
+        kfree(map->pages);
+        kfree(map->grants);
+        kfree(map->map_ops);
+        kfree(map->unmap_ops);
+        kfree(map->kmap_ops);
+        kfree(map);
+}
+
 static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
 {
         struct grant_map *add;
@@ -142,12 +157,7 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
         return add;
 
 err:
-        kfree(add->pages);
-        kfree(add->grants);
-        kfree(add->map_ops);
-        kfree(add->unmap_ops);
-        kfree(add->kmap_ops);
-        kfree(add);
+        gntdev_free_map(add);
         return NULL;
 }
 
@@ -198,17 +208,9 @@ static void gntdev_put_map(struct grant_map *map)
                 evtchn_put(map->notify.event);
         }
 
-        if (map->pages) {
-                if (!use_ptemod)
-                        unmap_grant_pages(map, 0, map->count);
-
-                free_xenballooned_pages(map->count, map->pages);
-        }
-        kfree(map->pages);
-        kfree(map->grants);
-        kfree(map->map_ops);
-        kfree(map->unmap_ops);
-        kfree(map);
+        if (map->pages && !use_ptemod)
+                unmap_grant_pages(map, 0, map->count);
+        gntdev_free_map(map);
 }
 
 /* ------------------------------------------------------------------ */
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index b9d08987a5a..0bbbccbb1f1 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -405,13 +405,13 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
         down_write(&mm->mmap_sem);
 
         vma = find_vma(mm, m.addr);
-        ret = -EINVAL;
         if (!vma ||
             vma->vm_ops != &privcmd_vm_ops ||
             (m.addr != vma->vm_start) ||
             ((m.addr + (nr_pages << PAGE_SHIFT)) != vma->vm_end) ||
             !privcmd_enforce_singleshot_mapping(vma)) {
                 up_write(&mm->mmap_sem);
+                ret = -EINVAL;
                 goto out;
         }
         if (xen_feature(XENFEAT_auto_translated_physmap)) {
@@ -435,12 +435,16 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 
         up_write(&mm->mmap_sem);
 
-        if (state.global_error && (version == 1)) {
-                /* Write back errors in second pass. */
-                state.user_mfn = (xen_pfn_t *)m.arr;
-                state.err      = err_array;
-                ret = traverse_pages(m.num, sizeof(xen_pfn_t),
-                                     &pagelist, mmap_return_errors_v1, &state);
+        if (version == 1) {
+                if (state.global_error) {
+                        /* Write back errors in second pass. */
+                        state.user_mfn = (xen_pfn_t *)m.arr;
+                        state.err      = err_array;
+                        ret = traverse_pages(m.num, sizeof(xen_pfn_t),
+                                             &pagelist, mmap_return_errors_v1, &state);
+                } else
+                        ret = 0;
+
         } else if (version == 2) {
                 ret = __copy_to_user(m.err, err_array, m.num * sizeof(int));
                 if (ret)
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 129e1674f4a..cd50d251998 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -362,7 +362,7 @@ static int __devinit pcistub_init_device(struct pci_dev *dev)
         if (!dev_data->pci_saved_state)
                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
         else {
-                dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n");
+                dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
                 __pci_reset_function_locked(dev);
                 pci_restore_state(dev);
         }
diff --git a/drivers/xen/xen-selfballoon.c b/drivers/xen/xen-selfballoon.c
index 7d041cb6da2..2552d3e0a70 100644
--- a/drivers/xen/xen-selfballoon.c
+++ b/drivers/xen/xen-selfballoon.c
@@ -222,7 +222,7 @@ static void selfballoon_process(struct work_struct *work)
         if (xen_selfballooning_enabled) {
                 cur_pages = totalram_pages;
                 tgt_pages = cur_pages; /* default is no change */
-                goal_pages = percpu_counter_read_positive(&vm_committed_as) +
+                goal_pages = vm_memory_committed() +
                                 totalreserve_pages +
                                 MB2PAGES(selfballoon_reserved_mb);
 #ifdef CONFIG_FRONTSWAP
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 89f76252a16..ac727028e65 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -458,7 +458,7 @@ static ssize_t xenbus_file_write(struct file *filp,
                 goto out;
 
         /* Can't write a xenbus message larger we can buffer */
-        if ((len + u->len) > sizeof(u->u.buffer)) {
+        if (len > sizeof(u->u.buffer) - u->len) {
                 /* On error, dump existing buffer */
                 u->len = 0;
                 rc = -EINVAL;