#define EFI_DEBUG 1
#define PFX "EFI: "
-int efi_enabled;
-EXPORT_SYMBOL(efi_enabled);
+#define EFI_MIN_RESERVE 5120
+
+#define EFI_DUMMY_GUID \
+ EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
+
+static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };
struct efi __read_mostly efi = {
.mps = EFI_INVALID_TABLE_ADDR,
static struct efi efi_phys __initdata;
static efi_system_table_t efi_systab __initdata;
+static inline bool efi_is_native(void)
+{
+ return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
+}
+
+unsigned long x86_efi_facility;
+
+/*
+ * Returns 1 if 'facility' is enabled, 0 otherwise.
+ */
+int efi_enabled(int facility)
+{
+ return test_bit(facility, &x86_efi_facility) != 0;
+}
+EXPORT_SYMBOL(efi_enabled);
+
+static bool disable_runtime = false;
static int __init setup_noefi(char *arg)
{
- efi_enabled = 0;
+ disable_runtime = true;
return 0;
}
early_param("noefi", setup_noefi);
}
early_param("add_efi_memmap", setup_add_efi_memmap);
+static bool efi_no_storage_paranoia;
+
+static int __init setup_storage_paranoia(char *arg)
+{
+ efi_no_storage_paranoia = true;
+ return 0;
+}
+early_param("efi_no_storage_paranoia", setup_storage_paranoia);
+
static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
{
* - Not within any part of the kernel
* - Not the bios reserved area
*/
- if ((start+size >= virt_to_phys(_text)
+ if ((start + size > virt_to_phys(_text)
&& start <= virt_to_phys(_end)) ||
!e820_all_mapped(start, start+size, E820_RAM) ||
memblock_x86_check_reserved_size(&start, &size,
int i = 0;
void *tmp;
+ if (!efi_is_native())
+ return;
+
#ifdef CONFIG_X86_32
efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
#else
efi.systab->hdr.revision >> 16,
efi.systab->hdr.revision & 0xffff);
+ set_bit(EFI_SYSTEM_TABLES, &x86_efi_facility);
+
/*
* Show what we know for posterity
*/
early_iounmap(config_tables,
efi.systab->nr_tables * sizeof(efi_config_table_t));
- /*
- * Check out the runtime services table. We need to map
- * the runtime services table so that we can grab the physical
- * address of several of the EFI runtime functions, needed to
- * set the firmware into virtual mode.
- */
- runtime = early_ioremap((unsigned long)efi.systab->runtime,
- sizeof(efi_runtime_services_t));
- if (runtime != NULL) {
- /*
- * We will only need *early* access to the following
- * two EFI runtime services before set_virtual_address_map
- * is invoked.
- */
- efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
- efi_phys.set_virtual_address_map =
- (efi_set_virtual_address_map_t *)
- runtime->set_virtual_address_map;
+ set_bit(EFI_CONFIG_TABLES, &x86_efi_facility);
+
+ if (!disable_runtime) {
/*
- * Make efi_get_time can be called before entering
- * virtual mode.
+ * Check out the runtime services table. We need to map
+ * the runtime services table so that we can grab the physical
+ * address of several of the EFI runtime functions, needed to
+ * set the firmware into virtual mode.
*/
- efi.get_time = phys_efi_get_time;
- } else
- printk(KERN_ERR "Could not map the EFI runtime service "
- "table!\n");
- early_iounmap(runtime, sizeof(efi_runtime_services_t));
+ runtime = early_ioremap((unsigned long)efi.systab->runtime,
+ sizeof(efi_runtime_services_t));
+ if (runtime != NULL) {
+ /*
+ * We will only need *early* access to the following
+ * two EFI runtime services before set_virtual_address_map
+ * is invoked.
+ */
+ efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
+ efi_phys.set_virtual_address_map =
+ (efi_set_virtual_address_map_t *)
+ runtime->set_virtual_address_map;
+ /*
+ * Make efi_get_time can be called before entering
+ * virtual mode.
+ */
+ efi.get_time = phys_efi_get_time;
+
+ set_bit(EFI_RUNTIME_SERVICES, &x86_efi_facility);
+ } else
+ printk(KERN_ERR "Could not map the EFI runtime service "
+ "table!\n");
+ early_iounmap(runtime, sizeof(efi_runtime_services_t));
+ }
/* Map the EFI memory map */
memmap.map = early_ioremap((unsigned long)memmap.phys_map,
if (add_efi_memmap)
do_add_efi_memmap();
-#ifdef CONFIG_X86_32
- x86_platform.get_wallclock = efi_get_time;
- x86_platform.set_wallclock = efi_set_rtc_mmss;
-#endif
+ set_bit(EFI_MEMMAP, &x86_efi_facility);
#if EFI_DEBUG
print_efi_memmap();
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
- if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
- md->type != EFI_BOOT_SERVICES_CODE &&
- md->type != EFI_BOOT_SERVICES_DATA)
- continue;
+ if (!(md->attribute & EFI_MEMORY_RUNTIME)) {
+#ifdef CONFIG_X86_64
+ if (md->type != EFI_BOOT_SERVICES_CODE &&
+ md->type != EFI_BOOT_SERVICES_DATA)
+#endif
+ continue;
+ }
size = md->num_pages << EFI_PAGE_SHIFT;
end = md->phys_addr + size;
*
* Call EFI services through wrapper functions.
*/
+ efi.runtime_version = efi_systab.hdr.revision;
efi.get_time = virt_efi_get_time;
efi.set_time = virt_efi_set_time;
efi.get_wakeup_time = virt_efi_get_wakeup_time;
efi.query_capsule_caps = virt_efi_query_capsule_caps;
if (__supported_pte_mask & _PAGE_NX)
runtime_code_page_mkexec();
+ clear_bit(EFI_MEMMAP, &x86_efi_facility);
early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
memmap.map = NULL;
kfree(new_memmap);
+
+ /* clean DUMMY object */
+ efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+ EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS,
+ 0, NULL);
}
/*
efi_memory_desc_t *md;
void *p;
+ if (!efi_enabled(EFI_MEMMAP))
+ return 0;
+
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
if ((md->phys_addr <= phys_addr) &&
}
return 0;
}
+
+/*
+ * Some firmware has serious problems when using more than 50% of the EFI
+ * variable store, i.e. it triggers bugs that can brick machines. Ensure that
+ * we never use more than this safe limit.
+ *
+ * Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
+ * store.
+ */
+efi_status_t efi_query_variable_store(u32 attributes, unsigned long size)
+{
+ efi_status_t status;
+ u64 storage_size, remaining_size, max_size;
+
+ if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
+ return 0;
+
+ status = efi.query_variable_info(attributes, &storage_size,
+ &remaining_size, &max_size);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ /*
+ * Some firmware implementations refuse to boot if there's insufficient
+ * space in the variable store. We account for that by refusing the
+ * write if permitting it would reduce the available space to under
+ * 5KB. This figure was provided by Samsung, so should be safe.
+ */
+ if ((remaining_size - size < EFI_MIN_RESERVE) &&
+ !efi_no_storage_paranoia) {
+
+ /*
+ * Triggering garbage collection may require that the firmware
+ * generate a real EFI_OUT_OF_RESOURCES error. We can force
+ * that by attempting to use more space than is available.
+ */
+ unsigned long dummy_size = remaining_size + 1024;
+ void *dummy = kzalloc(dummy_size, GFP_ATOMIC);
+
+ if (!dummy)
+ return EFI_OUT_OF_RESOURCES;
+
+ status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+ EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS,
+ dummy_size, dummy);
+
+ if (status == EFI_SUCCESS) {
+ /*
+ * This should have failed, so if it didn't make sure
+ * that we delete it...
+ */
+ efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID,
+ EFI_VARIABLE_NON_VOLATILE |
+ EFI_VARIABLE_BOOTSERVICE_ACCESS |
+ EFI_VARIABLE_RUNTIME_ACCESS,
+ 0, dummy);
+ }
+
+ kfree(dummy);
+
+ /*
+ * The runtime code may now have triggered a garbage collection
+ * run, so check the variable info again
+ */
+ status = efi.query_variable_info(attributes, &storage_size,
+ &remaining_size, &max_size);
+
+ if (status != EFI_SUCCESS)
+ return status;
+
+ /*
+ * There still isn't enough room, so return an error
+ */
+ if (remaining_size - size < EFI_MIN_RESERVE)
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ return EFI_SUCCESS;
+}
+EXPORT_SYMBOL_GPL(efi_query_variable_store);
git.openpandora.org / pandora-kernel.git / blobdiff