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-rw-r--r--arch/x86/platform/efi/efi.c901
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diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
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+++ b/arch/x86/platform/efi/efi.c
@@ -0,0 +1,901 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common EFI (Extensible Firmware Interface) support functions
+ * Based on Extensible Firmware Interface Specification version 1.0
+ *
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999-2002 Hewlett-Packard Co.
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ * Stephane Eranian <eranian@hpl.hp.com>
+ * Copyright (C) 2005-2008 Intel Co.
+ * Fenghua Yu <fenghua.yu@intel.com>
+ * Bibo Mao <bibo.mao@intel.com>
+ * Chandramouli Narayanan <mouli@linux.intel.com>
+ * Huang Ying <ying.huang@intel.com>
+ * Copyright (C) 2013 SuSE Labs
+ * Borislav Petkov <bp@suse.de> - runtime services VA mapping
+ *
+ * Copied from efi_32.c to eliminate the duplicated code between EFI
+ * 32/64 support code. --ying 2007-10-26
+ *
+ * All EFI Runtime Services are not implemented yet as EFI only
+ * supports physical mode addressing on SoftSDV. This is to be fixed
+ * in a future version. --drummond 1999-07-20
+ *
+ * Implemented EFI runtime services and virtual mode calls. --davidm
+ *
+ * Goutham Rao: <goutham.rao@intel.com>
+ * Skip non-WB memory and ignore empty memory ranges.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/efi.h>
+#include <linux/efi-bgrt.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/time.h>
+#include <linux/io.h>
+#include <linux/reboot.h>
+#include <linux/bcd.h>
+
+#include <asm/setup.h>
+#include <asm/efi.h>
+#include <asm/e820/api.h>
+#include <asm/time.h>
+#include <asm/tlbflush.h>
+#include <asm/x86_init.h>
+#include <asm/uv/uv.h>
+
+static unsigned long efi_systab_phys __initdata;
+static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR;
+static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR;
+static unsigned long efi_runtime, efi_nr_tables;
+
+unsigned long efi_fw_vendor, efi_config_table;
+
+static const efi_config_table_type_t arch_tables[] __initconst = {
+ {EFI_PROPERTIES_TABLE_GUID, &prop_phys, "PROP" },
+ {UGA_IO_PROTOCOL_GUID, &uga_phys, "UGA" },
+#ifdef CONFIG_X86_UV
+ {UV_SYSTEM_TABLE_GUID, &uv_systab_phys, "UVsystab" },
+#endif
+ {},
+};
+
+static const unsigned long * const efi_tables[] = {
+ &efi.acpi,
+ &efi.acpi20,
+ &efi.smbios,
+ &efi.smbios3,
+ &uga_phys,
+#ifdef CONFIG_X86_UV
+ &uv_systab_phys,
+#endif
+ &efi_fw_vendor,
+ &efi_runtime,
+ &efi_config_table,
+ &efi.esrt,
+ &prop_phys,
+ &efi_mem_attr_table,
+#ifdef CONFIG_EFI_RCI2_TABLE
+ &rci2_table_phys,
+#endif
+ &efi.tpm_log,
+ &efi.tpm_final_log,
+ &efi_rng_seed,
+#ifdef CONFIG_LOAD_UEFI_KEYS
+ &efi.mokvar_table,
+#endif
+#ifdef CONFIG_EFI_COCO_SECRET
+ &efi.coco_secret,
+#endif
+};
+
+u64 efi_setup; /* efi setup_data physical address */
+
+static int add_efi_memmap __initdata;
+static int __init setup_add_efi_memmap(char *arg)
+{
+ add_efi_memmap = 1;
+ return 0;
+}
+early_param("add_efi_memmap", setup_add_efi_memmap);
+
+/*
+ * Tell the kernel about the EFI memory map. This might include
+ * more than the max 128 entries that can fit in the passed in e820
+ * legacy (zeropage) memory map, but the kernel's e820 table can hold
+ * E820_MAX_ENTRIES.
+ */
+
+static void __init do_add_efi_memmap(void)
+{
+ efi_memory_desc_t *md;
+
+ if (!efi_enabled(EFI_MEMMAP))
+ return;
+
+ for_each_efi_memory_desc(md) {
+ unsigned long long start = md->phys_addr;
+ unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
+ int e820_type;
+
+ switch (md->type) {
+ case EFI_LOADER_CODE:
+ case EFI_LOADER_DATA:
+ case EFI_BOOT_SERVICES_CODE:
+ case EFI_BOOT_SERVICES_DATA:
+ case EFI_CONVENTIONAL_MEMORY:
+ if (efi_soft_reserve_enabled()
+ && (md->attribute & EFI_MEMORY_SP))
+ e820_type = E820_TYPE_SOFT_RESERVED;
+ else if (md->attribute & EFI_MEMORY_WB)
+ e820_type = E820_TYPE_RAM;
+ else
+ e820_type = E820_TYPE_RESERVED;
+ break;
+ case EFI_ACPI_RECLAIM_MEMORY:
+ e820_type = E820_TYPE_ACPI;
+ break;
+ case EFI_ACPI_MEMORY_NVS:
+ e820_type = E820_TYPE_NVS;
+ break;
+ case EFI_UNUSABLE_MEMORY:
+ e820_type = E820_TYPE_UNUSABLE;
+ break;
+ case EFI_PERSISTENT_MEMORY:
+ e820_type = E820_TYPE_PMEM;
+ break;
+ default:
+ /*
+ * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
+ * EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
+ * EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
+ */
+ e820_type = E820_TYPE_RESERVED;
+ break;
+ }
+
+ e820__range_add(start, size, e820_type);
+ }
+ e820__update_table(e820_table);
+}
+
+/*
+ * Given add_efi_memmap defaults to 0 and there is no alternative
+ * e820 mechanism for soft-reserved memory, import the full EFI memory
+ * map if soft reservations are present and enabled. Otherwise, the
+ * mechanism to disable the kernel's consideration of EFI_MEMORY_SP is
+ * the efi=nosoftreserve option.
+ */
+static bool do_efi_soft_reserve(void)
+{
+ efi_memory_desc_t *md;
+
+ if (!efi_enabled(EFI_MEMMAP))
+ return false;
+
+ if (!efi_soft_reserve_enabled())
+ return false;
+
+ for_each_efi_memory_desc(md)
+ if (md->type == EFI_CONVENTIONAL_MEMORY &&
+ (md->attribute & EFI_MEMORY_SP))
+ return true;
+ return false;
+}
+
+int __init efi_memblock_x86_reserve_range(void)
+{
+ struct efi_info *e = &boot_params.efi_info;
+ struct efi_memory_map_data data;
+ phys_addr_t pmap;
+ int rv;
+
+ if (efi_enabled(EFI_PARAVIRT))
+ return 0;
+
+ /* Can't handle firmware tables above 4GB on i386 */
+ if (IS_ENABLED(CONFIG_X86_32) && e->efi_memmap_hi > 0) {
+ pr_err("Memory map is above 4GB, disabling EFI.\n");
+ return -EINVAL;
+ }
+ pmap = (phys_addr_t)(e->efi_memmap | ((u64)e->efi_memmap_hi << 32));
+
+ data.phys_map = pmap;
+ data.size = e->efi_memmap_size;
+ data.desc_size = e->efi_memdesc_size;
+ data.desc_version = e->efi_memdesc_version;
+
+ rv = efi_memmap_init_early(&data);
+ if (rv)
+ return rv;
+
+ if (add_efi_memmap || do_efi_soft_reserve())
+ do_add_efi_memmap();
+
+ efi_fake_memmap_early();
+
+ WARN(efi.memmap.desc_version != 1,
+ "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
+ efi.memmap.desc_version);
+
+ memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
+ set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
+
+ return 0;
+}
+
+#define OVERFLOW_ADDR_SHIFT (64 - EFI_PAGE_SHIFT)
+#define OVERFLOW_ADDR_MASK (U64_MAX << OVERFLOW_ADDR_SHIFT)
+#define U64_HIGH_BIT (~(U64_MAX >> 1))
+
+static bool __init efi_memmap_entry_valid(const efi_memory_desc_t *md, int i)
+{
+ u64 end = (md->num_pages << EFI_PAGE_SHIFT) + md->phys_addr - 1;
+ u64 end_hi = 0;
+ char buf[64];
+
+ if (md->num_pages == 0) {
+ end = 0;
+ } else if (md->num_pages > EFI_PAGES_MAX ||
+ EFI_PAGES_MAX - md->num_pages <
+ (md->phys_addr >> EFI_PAGE_SHIFT)) {
+ end_hi = (md->num_pages & OVERFLOW_ADDR_MASK)
+ >> OVERFLOW_ADDR_SHIFT;
+
+ if ((md->phys_addr & U64_HIGH_BIT) && !(end & U64_HIGH_BIT))
+ end_hi += 1;
+ } else {
+ return true;
+ }
+
+ pr_warn_once(FW_BUG "Invalid EFI memory map entries:\n");
+
+ if (end_hi) {
+ pr_warn("mem%02u: %s range=[0x%016llx-0x%llx%016llx] (invalid)\n",
+ i, efi_md_typeattr_format(buf, sizeof(buf), md),
+ md->phys_addr, end_hi, end);
+ } else {
+ pr_warn("mem%02u: %s range=[0x%016llx-0x%016llx] (invalid)\n",
+ i, efi_md_typeattr_format(buf, sizeof(buf), md),
+ md->phys_addr, end);
+ }
+ return false;
+}
+
+static void __init efi_clean_memmap(void)
+{
+ efi_memory_desc_t *out = efi.memmap.map;
+ const efi_memory_desc_t *in = out;
+ const efi_memory_desc_t *end = efi.memmap.map_end;
+ int i, n_removal;
+
+ for (i = n_removal = 0; in < end; i++) {
+ if (efi_memmap_entry_valid(in, i)) {
+ if (out != in)
+ memcpy(out, in, efi.memmap.desc_size);
+ out = (void *)out + efi.memmap.desc_size;
+ } else {
+ n_removal++;
+ }
+ in = (void *)in + efi.memmap.desc_size;
+ }
+
+ if (n_removal > 0) {
+ struct efi_memory_map_data data = {
+ .phys_map = efi.memmap.phys_map,
+ .desc_version = efi.memmap.desc_version,
+ .desc_size = efi.memmap.desc_size,
+ .size = efi.memmap.desc_size * (efi.memmap.nr_map - n_removal),
+ .flags = 0,
+ };
+
+ pr_warn("Removing %d invalid memory map entries.\n", n_removal);
+ efi_memmap_install(&data);
+ }
+}
+
+void __init efi_print_memmap(void)
+{
+ efi_memory_desc_t *md;
+ int i = 0;
+
+ for_each_efi_memory_desc(md) {
+ char buf[64];
+
+ pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
+ i++, efi_md_typeattr_format(buf, sizeof(buf), md),
+ md->phys_addr,
+ md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
+ (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
+ }
+}
+
+static int __init efi_systab_init(unsigned long phys)
+{
+ int size = efi_enabled(EFI_64BIT) ? sizeof(efi_system_table_64_t)
+ : sizeof(efi_system_table_32_t);
+ const efi_table_hdr_t *hdr;
+ bool over4g = false;
+ void *p;
+ int ret;
+
+ hdr = p = early_memremap_ro(phys, size);
+ if (p == NULL) {
+ pr_err("Couldn't map the system table!\n");
+ return -ENOMEM;
+ }
+
+ ret = efi_systab_check_header(hdr, 1);
+ if (ret) {
+ early_memunmap(p, size);
+ return ret;
+ }
+
+ if (efi_enabled(EFI_64BIT)) {
+ const efi_system_table_64_t *systab64 = p;
+
+ efi_runtime = systab64->runtime;
+ over4g = systab64->runtime > U32_MAX;
+
+ if (efi_setup) {
+ struct efi_setup_data *data;
+
+ data = early_memremap_ro(efi_setup, sizeof(*data));
+ if (!data) {
+ early_memunmap(p, size);
+ return -ENOMEM;
+ }
+
+ efi_fw_vendor = (unsigned long)data->fw_vendor;
+ efi_config_table = (unsigned long)data->tables;
+
+ over4g |= data->fw_vendor > U32_MAX ||
+ data->tables > U32_MAX;
+
+ early_memunmap(data, sizeof(*data));
+ } else {
+ efi_fw_vendor = systab64->fw_vendor;
+ efi_config_table = systab64->tables;
+
+ over4g |= systab64->fw_vendor > U32_MAX ||
+ systab64->tables > U32_MAX;
+ }
+ efi_nr_tables = systab64->nr_tables;
+ } else {
+ const efi_system_table_32_t *systab32 = p;
+
+ efi_fw_vendor = systab32->fw_vendor;
+ efi_runtime = systab32->runtime;
+ efi_config_table = systab32->tables;
+ efi_nr_tables = systab32->nr_tables;
+ }
+
+ efi.runtime_version = hdr->revision;
+
+ efi_systab_report_header(hdr, efi_fw_vendor);
+ early_memunmap(p, size);
+
+ if (IS_ENABLED(CONFIG_X86_32) && over4g) {
+ pr_err("EFI data located above 4GB, disabling EFI.\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init efi_config_init(const efi_config_table_type_t *arch_tables)
+{
+ void *config_tables;
+ int sz, ret;
+
+ if (efi_nr_tables == 0)
+ return 0;
+
+ if (efi_enabled(EFI_64BIT))
+ sz = sizeof(efi_config_table_64_t);
+ else
+ sz = sizeof(efi_config_table_32_t);
+
+ /*
+ * Let's see what config tables the firmware passed to us.
+ */
+ config_tables = early_memremap(efi_config_table, efi_nr_tables * sz);
+ if (config_tables == NULL) {
+ pr_err("Could not map Configuration table!\n");
+ return -ENOMEM;
+ }
+
+ ret = efi_config_parse_tables(config_tables, efi_nr_tables,
+ arch_tables);
+
+ early_memunmap(config_tables, efi_nr_tables * sz);
+ return ret;
+}
+
+void __init efi_init(void)
+{
+ if (IS_ENABLED(CONFIG_X86_32) &&
+ (boot_params.efi_info.efi_systab_hi ||
+ boot_params.efi_info.efi_memmap_hi)) {
+ pr_info("Table located above 4GB, disabling EFI.\n");
+ return;
+ }
+
+ efi_systab_phys = boot_params.efi_info.efi_systab |
+ ((__u64)boot_params.efi_info.efi_systab_hi << 32);
+
+ if (efi_systab_init(efi_systab_phys))
+ return;
+
+ if (efi_reuse_config(efi_config_table, efi_nr_tables))
+ return;
+
+ if (efi_config_init(arch_tables))
+ return;
+
+ /*
+ * Note: We currently don't support runtime services on an EFI
+ * that doesn't match the kernel 32/64-bit mode.
+ */
+
+ if (!efi_runtime_supported())
+ pr_err("No EFI runtime due to 32/64-bit mismatch with kernel\n");
+
+ if (!efi_runtime_supported() || efi_runtime_disabled()) {
+ efi_memmap_unmap();
+ return;
+ }
+
+ /* Parse the EFI Properties table if it exists */
+ if (prop_phys != EFI_INVALID_TABLE_ADDR) {
+ efi_properties_table_t *tbl;
+
+ tbl = early_memremap_ro(prop_phys, sizeof(*tbl));
+ if (tbl == NULL) {
+ pr_err("Could not map Properties table!\n");
+ } else {
+ if (tbl->memory_protection_attribute &
+ EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
+ set_bit(EFI_NX_PE_DATA, &efi.flags);
+
+ early_memunmap(tbl, sizeof(*tbl));
+ }
+ }
+
+ set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ efi_clean_memmap();
+
+ if (efi_enabled(EFI_DBG))
+ efi_print_memmap();
+}
+
+/* Merge contiguous regions of the same type and attribute */
+static void __init efi_merge_regions(void)
+{
+ efi_memory_desc_t *md, *prev_md = NULL;
+
+ for_each_efi_memory_desc(md) {
+ u64 prev_size;
+
+ if (!prev_md) {
+ prev_md = md;
+ continue;
+ }
+
+ if (prev_md->type != md->type ||
+ prev_md->attribute != md->attribute) {
+ prev_md = md;
+ continue;
+ }
+
+ prev_size = prev_md->num_pages << EFI_PAGE_SHIFT;
+
+ if (md->phys_addr == (prev_md->phys_addr + prev_size)) {
+ prev_md->num_pages += md->num_pages;
+ md->type = EFI_RESERVED_TYPE;
+ md->attribute = 0;
+ continue;
+ }
+ prev_md = md;
+ }
+}
+
+static void *realloc_pages(void *old_memmap, int old_shift)
+{
+ void *ret;
+
+ ret = (void *)__get_free_pages(GFP_KERNEL, old_shift + 1);
+ if (!ret)
+ goto out;
+
+ /*
+ * A first-time allocation doesn't have anything to copy.
+ */
+ if (!old_memmap)
+ return ret;
+
+ memcpy(ret, old_memmap, PAGE_SIZE << old_shift);
+
+out:
+ free_pages((unsigned long)old_memmap, old_shift);
+ return ret;
+}
+
+/*
+ * Iterate the EFI memory map in reverse order because the regions
+ * will be mapped top-down. The end result is the same as if we had
+ * mapped things forward, but doesn't require us to change the
+ * existing implementation of efi_map_region().
+ */
+static inline void *efi_map_next_entry_reverse(void *entry)
+{
+ /* Initial call */
+ if (!entry)
+ return efi.memmap.map_end - efi.memmap.desc_size;
+
+ entry -= efi.memmap.desc_size;
+ if (entry < efi.memmap.map)
+ return NULL;
+
+ return entry;
+}
+
+/*
+ * efi_map_next_entry - Return the next EFI memory map descriptor
+ * @entry: Previous EFI memory map descriptor
+ *
+ * This is a helper function to iterate over the EFI memory map, which
+ * we do in different orders depending on the current configuration.
+ *
+ * To begin traversing the memory map @entry must be %NULL.
+ *
+ * Returns %NULL when we reach the end of the memory map.
+ */
+static void *efi_map_next_entry(void *entry)
+{
+ if (efi_enabled(EFI_64BIT)) {
+ /*
+ * Starting in UEFI v2.5 the EFI_PROPERTIES_TABLE
+ * config table feature requires us to map all entries
+ * in the same order as they appear in the EFI memory
+ * map. That is to say, entry N must have a lower
+ * virtual address than entry N+1. This is because the
+ * firmware toolchain leaves relative references in
+ * the code/data sections, which are split and become
+ * separate EFI memory regions. Mapping things
+ * out-of-order leads to the firmware accessing
+ * unmapped addresses.
+ *
+ * Since we need to map things this way whether or not
+ * the kernel actually makes use of
+ * EFI_PROPERTIES_TABLE, let's just switch to this
+ * scheme by default for 64-bit.
+ */
+ return efi_map_next_entry_reverse(entry);
+ }
+
+ /* Initial call */
+ if (!entry)
+ return efi.memmap.map;
+
+ entry += efi.memmap.desc_size;
+ if (entry >= efi.memmap.map_end)
+ return NULL;
+
+ return entry;
+}
+
+static bool should_map_region(efi_memory_desc_t *md)
+{
+ /*
+ * Runtime regions always require runtime mappings (obviously).
+ */
+ if (md->attribute & EFI_MEMORY_RUNTIME)
+ return true;
+
+ /*
+ * 32-bit EFI doesn't suffer from the bug that requires us to
+ * reserve boot services regions, and mixed mode support
+ * doesn't exist for 32-bit kernels.
+ */
+ if (IS_ENABLED(CONFIG_X86_32))
+ return false;
+
+ /*
+ * EFI specific purpose memory may be reserved by default
+ * depending on kernel config and boot options.
+ */
+ if (md->type == EFI_CONVENTIONAL_MEMORY &&
+ efi_soft_reserve_enabled() &&
+ (md->attribute & EFI_MEMORY_SP))
+ return false;
+
+ /*
+ * Map all of RAM so that we can access arguments in the 1:1
+ * mapping when making EFI runtime calls.
+ */
+ if (efi_is_mixed()) {
+ if (md->type == EFI_CONVENTIONAL_MEMORY ||
+ md->type == EFI_LOADER_DATA ||
+ md->type == EFI_LOADER_CODE)
+ return true;
+ }
+
+ /*
+ * Map boot services regions as a workaround for buggy
+ * firmware that accesses them even when they shouldn't.
+ *
+ * See efi_{reserve,free}_boot_services().
+ */
+ if (md->type == EFI_BOOT_SERVICES_CODE ||
+ md->type == EFI_BOOT_SERVICES_DATA)
+ return true;
+
+ return false;
+}
+
+/*
+ * Map the efi memory ranges of the runtime services and update new_mmap with
+ * virtual addresses.
+ */
+static void * __init efi_map_regions(int *count, int *pg_shift)
+{
+ void *p, *new_memmap = NULL;
+ unsigned long left = 0;
+ unsigned long desc_size;
+ efi_memory_desc_t *md;
+
+ desc_size = efi.memmap.desc_size;
+
+ p = NULL;
+ while ((p = efi_map_next_entry(p))) {
+ md = p;
+
+ if (!should_map_region(md))
+ continue;
+
+ efi_map_region(md);
+
+ if (left < desc_size) {
+ new_memmap = realloc_pages(new_memmap, *pg_shift);
+ if (!new_memmap)
+ return NULL;
+
+ left += PAGE_SIZE << *pg_shift;
+ (*pg_shift)++;
+ }
+
+ memcpy(new_memmap + (*count * desc_size), md, desc_size);
+
+ left -= desc_size;
+ (*count)++;
+ }
+
+ return new_memmap;
+}
+
+static void __init kexec_enter_virtual_mode(void)
+{
+#ifdef CONFIG_KEXEC_CORE
+ efi_memory_desc_t *md;
+ unsigned int num_pages;
+
+ /*
+ * We don't do virtual mode, since we don't do runtime services, on
+ * non-native EFI.
+ */
+ if (efi_is_mixed()) {
+ efi_memmap_unmap();
+ clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ return;
+ }
+
+ if (efi_alloc_page_tables()) {
+ pr_err("Failed to allocate EFI page tables\n");
+ clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ return;
+ }
+
+ /*
+ * Map efi regions which were passed via setup_data. The virt_addr is a
+ * fixed addr which was used in first kernel of a kexec boot.
+ */
+ for_each_efi_memory_desc(md)
+ efi_map_region_fixed(md); /* FIXME: add error handling */
+
+ /*
+ * Unregister the early EFI memmap from efi_init() and install
+ * the new EFI memory map.
+ */
+ efi_memmap_unmap();
+
+ if (efi_memmap_init_late(efi.memmap.phys_map,
+ efi.memmap.desc_size * efi.memmap.nr_map)) {
+ pr_err("Failed to remap late EFI memory map\n");
+ clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ return;
+ }
+
+ num_pages = ALIGN(efi.memmap.nr_map * efi.memmap.desc_size, PAGE_SIZE);
+ num_pages >>= PAGE_SHIFT;
+
+ if (efi_setup_page_tables(efi.memmap.phys_map, num_pages)) {
+ clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ return;
+ }
+
+ efi_sync_low_kernel_mappings();
+ efi_native_runtime_setup();
+#endif
+}
+
+/*
+ * This function will switch the EFI runtime services to virtual mode.
+ * Essentially, we look through the EFI memmap and map every region that
+ * has the runtime attribute bit set in its memory descriptor into the
+ * efi_pgd page table.
+ *
+ * The new method does a pagetable switch in a preemption-safe manner
+ * so that we're in a different address space when calling a runtime
+ * function. For function arguments passing we do copy the PUDs of the
+ * kernel page table into efi_pgd prior to each call.
+ *
+ * Specially for kexec boot, efi runtime maps in previous kernel should
+ * be passed in via setup_data. In that case runtime ranges will be mapped
+ * to the same virtual addresses as the first kernel, see
+ * kexec_enter_virtual_mode().
+ */
+static void __init __efi_enter_virtual_mode(void)
+{
+ int count = 0, pg_shift = 0;
+ void *new_memmap = NULL;
+ efi_status_t status;
+ unsigned long pa;
+
+ if (efi_alloc_page_tables()) {
+ pr_err("Failed to allocate EFI page tables\n");
+ goto err;
+ }
+
+ efi_merge_regions();
+ new_memmap = efi_map_regions(&count, &pg_shift);
+ if (!new_memmap) {
+ pr_err("Error reallocating memory, EFI runtime non-functional!\n");
+ goto err;
+ }
+
+ pa = __pa(new_memmap);
+
+ /*
+ * Unregister the early EFI memmap from efi_init() and install
+ * the new EFI memory map that we are about to pass to the
+ * firmware via SetVirtualAddressMap().
+ */
+ efi_memmap_unmap();
+
+ if (efi_memmap_init_late(pa, efi.memmap.desc_size * count)) {
+ pr_err("Failed to remap late EFI memory map\n");
+ goto err;
+ }
+
+ if (efi_enabled(EFI_DBG)) {
+ pr_info("EFI runtime memory map:\n");
+ efi_print_memmap();
+ }
+
+ if (efi_setup_page_tables(pa, 1 << pg_shift))
+ goto err;
+
+ efi_sync_low_kernel_mappings();
+
+ status = efi_set_virtual_address_map(efi.memmap.desc_size * count,
+ efi.memmap.desc_size,
+ efi.memmap.desc_version,
+ (efi_memory_desc_t *)pa,
+ efi_systab_phys);
+ if (status != EFI_SUCCESS) {
+ pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n",
+ status);
+ goto err;
+ }
+
+ efi_check_for_embedded_firmwares();
+ efi_free_boot_services();
+
+ if (!efi_is_mixed())
+ efi_native_runtime_setup();
+ else
+ efi_thunk_runtime_setup();
+
+ /*
+ * Apply more restrictive page table mapping attributes now that
+ * SVAM() has been called and the firmware has performed all
+ * necessary relocation fixups for the new virtual addresses.
+ */
+ efi_runtime_update_mappings();
+
+ /* clean DUMMY object */
+ efi_delete_dummy_variable();
+ return;
+
+err:
+ clear_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+}
+
+void __init efi_enter_virtual_mode(void)
+{
+ if (efi_enabled(EFI_PARAVIRT))
+ return;
+
+ efi.runtime = (efi_runtime_services_t *)efi_runtime;
+
+ if (efi_setup)
+ kexec_enter_virtual_mode();
+ else
+ __efi_enter_virtual_mode();
+
+ efi_dump_pagetable();
+}
+
+bool efi_is_table_address(unsigned long phys_addr)
+{
+ unsigned int i;
+
+ if (phys_addr == EFI_INVALID_TABLE_ADDR)
+ return false;
+
+ for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
+ if (*(efi_tables[i]) == phys_addr)
+ return true;
+
+ return false;
+}
+
+char *efi_systab_show_arch(char *str)
+{
+ if (uga_phys != EFI_INVALID_TABLE_ADDR)
+ str += sprintf(str, "UGA=0x%lx\n", uga_phys);
+ return str;
+}
+
+#define EFI_FIELD(var) efi_ ## var
+
+#define EFI_ATTR_SHOW(name) \
+static ssize_t name##_show(struct kobject *kobj, \
+ struct kobj_attribute *attr, char *buf) \
+{ \
+ return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
+}
+
+EFI_ATTR_SHOW(fw_vendor);
+EFI_ATTR_SHOW(runtime);
+EFI_ATTR_SHOW(config_table);
+
+struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
+struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
+struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
+
+umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n)
+{
+ if (attr == &efi_attr_fw_vendor.attr) {
+ if (efi_enabled(EFI_PARAVIRT) ||
+ efi_fw_vendor == EFI_INVALID_TABLE_ADDR)
+ return 0;
+ } else if (attr == &efi_attr_runtime.attr) {
+ if (efi_runtime == EFI_INVALID_TABLE_ADDR)
+ return 0;
+ } else if (attr == &efi_attr_config_table.attr) {
+ if (efi_config_table == EFI_INVALID_TABLE_ADDR)
+ return 0;
+ }
+ return attr->mode;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-12 15:09:16 +0000