diff options
Diffstat (limited to 'drivers/hv/vmbus_drv.c')
| -rw-r--r-- | drivers/hv/vmbus_drv.c | 37 |
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; |