3 files changed, 92 insertions, 28 deletions

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index e7b0bcd453e7..ee59e06c2194 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -102,10 +102,7 @@ static struct notifier_block hyperv_panic_block = {
         .notifier_call = hyperv_panic_event,
 };
 
-struct resource hyperv_mmio = {
-        .name  = "hyperv mmio",
-        .flags = IORESOURCE_MEM,
-};
+struct resource *hyperv_mmio;
 EXPORT_SYMBOL_GPL(hyperv_mmio);
 
 static int vmbus_exists(void)
@@ -1013,30 +1010,105 @@ void vmbus_device_unregister(struct hv_device *device_obj)
 
 
 /*
- * VMBUS is an acpi enumerated device. Get the the information we
+ * VMBUS is an acpi enumerated device. Get the information we
  * need from DSDT.
  */
-
+#define VTPM_BASE_ADDRESS 0xfed40000
 static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
 {
+        resource_size_t start = 0;
+        resource_size_t end = 0;
+        struct resource *new_res;
+        struct resource **old_res = &hyperv_mmio;
+        struct resource **prev_res = NULL;
+
         switch (res->type) {
         case ACPI_RESOURCE_TYPE_IRQ:
                 irq = res->data.irq.interrupts[0];
+                return AE_OK;
+
+        /*
+         * "Address" descriptors are for bus windows. Ignore
+         * "memory" descriptors, which are for registers on
+         * devices.
+         */
+        case ACPI_RESOURCE_TYPE_ADDRESS32:
+                start = res->data.address32.address.minimum;
+                end = res->data.address32.address.maximum;
                 break;
 
         case ACPI_RESOURCE_TYPE_ADDRESS64:
-                hyperv_mmio.start = res->data.address64.address.minimum;
-                hyperv_mmio.end = res->data.address64.address.maximum;
+                start = res->data.address64.address.minimum;
+                end = res->data.address64.address.maximum;
                 break;
+
+        default:
+                /* Unused resource type */
+                return AE_OK;
+
         }
+        /*
+         * Ignore ranges that are below 1MB, as they're not
+         * necessary or useful here.
+         */
+        if (end < 0x100000)
+                return AE_OK;
+
+        new_res = kzalloc(sizeof(*new_res), GFP_ATOMIC);
+        if (!new_res)
+                return AE_NO_MEMORY;
+
+        /* If this range overlaps the virtual TPM, truncate it. */
+        if (end > VTPM_BASE_ADDRESS && start < VTPM_BASE_ADDRESS)
+                end = VTPM_BASE_ADDRESS;
+
+        new_res->name = "hyperv mmio";
+        new_res->flags = IORESOURCE_MEM;
+        new_res->start = start;
+        new_res->end = end;
+
+        do {
+                if (!*old_res) {
+                        *old_res = new_res;
+                        break;
+                }
+
+                if ((*old_res)->end < new_res->start) {
+                        new_res->sibling = *old_res;
+                        if (prev_res)
+                                (*prev_res)->sibling = new_res;
+                        *old_res = new_res;
+                        break;
+                }
+
+                prev_res = old_res;
+                old_res = &(*old_res)->sibling;
+
+        } while (1);
 
         return AE_OK;
 }
 
+static int vmbus_acpi_remove(struct acpi_device *device)
+{
+        struct resource *cur_res;
+        struct resource *next_res;
+
+        if (hyperv_mmio) {
+                for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
+                        next_res = cur_res->sibling;
+                        kfree(cur_res);
+                }
+        }
+
+        return 0;
+}
+
 static int vmbus_acpi_add(struct acpi_device *device)
 {
         acpi_status result;
         int ret_val = -ENODEV;
+        struct acpi_device *ancestor;
 
         hv_acpi_dev = device;
 
@@ -1046,35 +1118,27 @@ static int vmbus_acpi_add(struct acpi_device *device)
         if (ACPI_FAILURE(result))
                 goto acpi_walk_err;
         /*
-         * The parent of the vmbus acpi device (Gen2 firmware) is the VMOD that
-         * has the mmio ranges. Get that.
+         * Some ancestor of the vmbus acpi device (Gen1 or Gen2
+         * firmware) is the VMOD that has the mmio ranges. Get that.
          */
-        if (device->parent) {
-                result = acpi_walk_resources(device->parent->handle,
-                                        METHOD_NAME__CRS,
-                                        vmbus_walk_resources, NULL);
+        for (ancestor = device->parent; ancestor; ancestor = ancestor->parent) {
+                result = acpi_walk_resources(ancestor->handle, METHOD_NAME__CRS,
+                                             vmbus_walk_resources, NULL);
 
                 if (ACPI_FAILURE(result))
-                        goto acpi_walk_err;
-                if (hyperv_mmio.start && hyperv_mmio.end)
-                        request_resource(&iomem_resource, &hyperv_mmio);
+                        continue;
+                if (hyperv_mmio)
+                        break;
         }
         ret_val = 0;
 
 acpi_walk_err:
         complete(&probe_event);
+        if (ret_val)
+                vmbus_acpi_remove(device);
         return ret_val;
 }
 
-static int vmbus_acpi_remove(struct acpi_device *device)
-{
-        int ret = 0;
-
-        if (hyperv_mmio.start && hyperv_mmio.end)
-                ret = release_resource(&hyperv_mmio);
-        return ret;
-}
-
 static const struct acpi_device_id vmbus_acpi_device_ids[] = {
         {"VMBUS", 0},
         {"VMBus", 0},
diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c
index 807ee22ef229..b54ee1c05a5f 100644
--- a/drivers/video/fbdev/hyperv_fb.c
+++ b/drivers/video/fbdev/hyperv_fb.c
@@ -688,7 +688,7 @@ static int hvfb_getmem(struct fb_info *info)
         par->mem.name = KBUILD_MODNAME;
         par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
         if (gen2vm) {
-                ret = allocate_resource(&hyperv_mmio, &par->mem,
+                ret = allocate_resource(hyperv_mmio, &par->mem,
                                         screen_fb_size,
                                         0, -1,
                                         screen_fb_size,
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 30d3a1f79450..217e14be77b9 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1233,7 +1233,7 @@ extern bool vmbus_prep_negotiate_resp(struct icmsg_hdr *,
 
 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);
 
-extern struct resource hyperv_mmio;
+extern struct resource *hyperv_mmio;
 
 /*
  * Negotiated version with the Host.