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path: root/drivers/hv/vmbus_drv.c
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Diffstat (limited to 'drivers/hv/vmbus_drv.c')
-rw-r--r--drivers/hv/vmbus_drv.c37
1 files changed, 36 insertions, 1 deletions
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index dfc6149ccc93..eaa5c3b7fd8a 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -41,6 +41,7 @@
#include <linux/ptrace.h>
#include <linux/screen_info.h>
#include <linux/kdebug.h>
+#include <linux/efi.h>
#include "hyperv_vmbus.h"
static struct acpi_device *hv_acpi_dev;
@@ -101,6 +102,8 @@ static struct notifier_block hyperv_panic_block = {
.notifier_call = hyperv_panic_event,
};
+static const char *fb_mmio_name = "fb_range";
+static struct resource *fb_mmio;
struct resource *hyperv_mmio;
DEFINE_SEMAPHORE(hyperv_mmio_lock);
@@ -1091,6 +1094,12 @@ static int vmbus_acpi_remove(struct acpi_device *device)
struct resource *next_res;
if (hyperv_mmio) {
+ if (fb_mmio) {
+ __release_region(hyperv_mmio, fb_mmio->start,
+ resource_size(fb_mmio));
+ fb_mmio = NULL;
+ }
+
for (cur_res = hyperv_mmio; cur_res; cur_res = next_res) {
next_res = cur_res->sibling;
kfree(cur_res);
@@ -1100,6 +1109,30 @@ static int vmbus_acpi_remove(struct acpi_device *device)
return 0;
}
+static void vmbus_reserve_fb(void)
+{
+ int size;
+ /*
+ * Make a claim for the frame buffer in the resource tree under the
+ * first node, which will be the one below 4GB. The length seems to
+ * be underreported, particularly in a Generation 1 VM. So start out
+ * reserving a larger area and make it smaller until it succeeds.
+ */
+
+ if (screen_info.lfb_base) {
+ if (efi_enabled(EFI_BOOT))
+ size = max_t(__u32, screen_info.lfb_size, 0x800000);
+ else
+ size = max_t(__u32, screen_info.lfb_size, 0x4000000);
+
+ for (; !fb_mmio && (size >= 0x100000); size >>= 1) {
+ fb_mmio = __request_region(hyperv_mmio,
+ screen_info.lfb_base, size,
+ fb_mmio_name, 0);
+ }
+ }
+}
+
/**
* vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
* @new: If successful, supplied a pointer to the
@@ -1261,8 +1294,10 @@ static int vmbus_acpi_add(struct acpi_device *device)
if (ACPI_FAILURE(result))
continue;
- if (hyperv_mmio)
+ if (hyperv_mmio) {
+ vmbus_reserve_fb();
break;
+ }
}
ret_val = 0;