// SPDX-License-Identifier: GPL-2.0
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/*
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* Common EFI (Extensible Firmware Interface) support functions
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* Based on Extensible Firmware Interface Specification version 1.0
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*
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* Copyright (C) 1999 VA Linux Systems
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* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
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* Copyright (C) 1999-2002 Hewlett-Packard Co.
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* David Mosberger-Tang <davidm@hpl.hp.com>
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* Stephane Eranian <eranian@hpl.hp.com>
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* Copyright (C) 2005-2008 Intel Co.
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* Fenghua Yu <fenghua.yu@intel.com>
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* Bibo Mao <bibo.mao@intel.com>
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* Chandramouli Narayanan <mouli@linux.intel.com>
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* Huang Ying <ying.huang@intel.com>
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* Copyright (C) 2013 SuSE Labs
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* Borislav Petkov <bp@suse.de> - runtime services VA mapping
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*
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* Copied from efi_32.c to eliminate the duplicated code between EFI
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* 32/64 support code. --ying 2007-10-26
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*
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* All EFI Runtime Services are not implemented yet as EFI only
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* supports physical mode addressing on SoftSDV. This is to be fixed
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* in a future version. --drummond 1999-07-20
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*
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* Implemented EFI runtime services and virtual mode calls. --davidm
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*
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* Goutham Rao: <goutham.rao@intel.com>
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* Skip non-WB memory and ignore empty memory ranges.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/efi.h>
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#include <linux/efi-bgrt.h>
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#include <linux/export.h>
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#include <linux/bootmem.h>
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#include <linux/slab.h>
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#include <linux/memblock.h>
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#include <linux/spinlock.h>
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#include <linux/uaccess.h>
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#include <linux/time.h>
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#include <linux/io.h>
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#include <linux/reboot.h>
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#include <linux/bcd.h>
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#include <asm/setup.h>
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#include <asm/efi.h>
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#include <asm/e820/api.h>
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#include <asm/time.h>
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#include <asm/set_memory.h>
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#include <asm/tlbflush.h>
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#include <asm/x86_init.h>
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#include <asm/uv/uv.h>
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static struct efi efi_phys __initdata;
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static efi_system_table_t efi_systab __initdata;
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static efi_config_table_type_t arch_tables[] __initdata = {
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#ifdef CONFIG_X86_UV
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{UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
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#endif
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{NULL_GUID, NULL, NULL},
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};
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u64 efi_setup; /* efi setup_data physical address */
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static int add_efi_memmap __initdata;
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static int __init setup_add_efi_memmap(char *arg)
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{
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add_efi_memmap = 1;
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return 0;
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}
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early_param("add_efi_memmap", setup_add_efi_memmap);
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static efi_status_t __init phys_efi_set_virtual_address_map(
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unsigned long memory_map_size,
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unsigned long descriptor_size,
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u32 descriptor_version,
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efi_memory_desc_t *virtual_map)
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{
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efi_status_t status;
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unsigned long flags;
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pgd_t *save_pgd;
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save_pgd = efi_call_phys_prolog();
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/* Disable interrupts around EFI calls: */
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local_irq_save(flags);
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status = efi_call_phys(efi_phys.set_virtual_address_map,
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memory_map_size, descriptor_size,
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descriptor_version, virtual_map);
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local_irq_restore(flags);
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efi_call_phys_epilog(save_pgd);
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return status;
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}
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void __init efi_find_mirror(void)
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{
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efi_memory_desc_t *md;
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u64 mirror_size = 0, total_size = 0;
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for_each_efi_memory_desc(md) {
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unsigned long long start = md->phys_addr;
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unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
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total_size += size;
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if (md->attribute & EFI_MEMORY_MORE_RELIABLE) {
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memblock_mark_mirror(start, size);
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mirror_size += size;
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}
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}
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if (mirror_size)
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pr_info("Memory: %lldM/%lldM mirrored memory\n",
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mirror_size>>20, total_size>>20);
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}
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/*
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* Tell the kernel about the EFI memory map. This might include
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* more than the max 128 entries that can fit in the e820 legacy
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* (zeropage) memory map.
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*/
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static void __init do_add_efi_memmap(void)
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{
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efi_memory_desc_t *md;
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for_each_efi_memory_desc(md) {
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unsigned long long start = md->phys_addr;
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unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
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int e820_type;
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switch (md->type) {
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case EFI_LOADER_CODE:
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case EFI_LOADER_DATA:
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case EFI_BOOT_SERVICES_CODE:
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case EFI_BOOT_SERVICES_DATA:
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case EFI_CONVENTIONAL_MEMORY:
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if (md->attribute & EFI_MEMORY_WB)
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e820_type = E820_TYPE_RAM;
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else
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e820_type = E820_TYPE_RESERVED;
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break;
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case EFI_ACPI_RECLAIM_MEMORY:
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e820_type = E820_TYPE_ACPI;
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break;
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case EFI_ACPI_MEMORY_NVS:
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e820_type = E820_TYPE_NVS;
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break;
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case EFI_UNUSABLE_MEMORY:
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e820_type = E820_TYPE_UNUSABLE;
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break;
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case EFI_PERSISTENT_MEMORY:
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e820_type = E820_TYPE_PMEM;
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break;
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default:
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/*
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* EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE
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* EFI_RUNTIME_SERVICES_DATA EFI_MEMORY_MAPPED_IO
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* EFI_MEMORY_MAPPED_IO_PORT_SPACE EFI_PAL_CODE
|
*/
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e820_type = E820_TYPE_RESERVED;
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break;
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}
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e820__range_add(start, size, e820_type);
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}
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e820__update_table(e820_table);
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}
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int __init efi_memblock_x86_reserve_range(void)
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{
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struct efi_info *e = &boot_params.efi_info;
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struct efi_memory_map_data data;
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phys_addr_t pmap;
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int rv;
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if (efi_enabled(EFI_PARAVIRT))
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return 0;
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#ifdef CONFIG_X86_32
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/* Can't handle data above 4GB at this time */
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if (e->efi_memmap_hi) {
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pr_err("Memory map is above 4GB, disabling EFI.\n");
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return -EINVAL;
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}
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pmap = e->efi_memmap;
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#else
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pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32));
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#endif
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data.phys_map = pmap;
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data.size = e->efi_memmap_size;
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data.desc_size = e->efi_memdesc_size;
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data.desc_version = e->efi_memdesc_version;
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rv = efi_memmap_init_early(&data);
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if (rv)
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return rv;
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if (add_efi_memmap)
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do_add_efi_memmap();
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WARN(efi.memmap.desc_version != 1,
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"Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
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efi.memmap.desc_version);
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memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
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return 0;
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}
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#define OVERFLOW_ADDR_SHIFT (64 - EFI_PAGE_SHIFT)
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#define OVERFLOW_ADDR_MASK (U64_MAX << OVERFLOW_ADDR_SHIFT)
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#define U64_HIGH_BIT (~(U64_MAX >> 1))
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static bool __init efi_memmap_entry_valid(const efi_memory_desc_t *md, int i)
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{
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u64 end = (md->num_pages << EFI_PAGE_SHIFT) + md->phys_addr - 1;
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u64 end_hi = 0;
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char buf[64];
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if (md->num_pages == 0) {
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end = 0;
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} else if (md->num_pages > EFI_PAGES_MAX ||
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EFI_PAGES_MAX - md->num_pages <
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(md->phys_addr >> EFI_PAGE_SHIFT)) {
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end_hi = (md->num_pages & OVERFLOW_ADDR_MASK)
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>> OVERFLOW_ADDR_SHIFT;
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if ((md->phys_addr & U64_HIGH_BIT) && !(end & U64_HIGH_BIT))
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end_hi += 1;
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} else {
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return true;
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}
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pr_warn_once(FW_BUG "Invalid EFI memory map entries:\n");
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if (end_hi) {
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pr_warn("mem%02u: %s range=[0x%016llx-0x%llx%016llx] (invalid)\n",
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i, efi_md_typeattr_format(buf, sizeof(buf), md),
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md->phys_addr, end_hi, end);
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} else {
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pr_warn("mem%02u: %s range=[0x%016llx-0x%016llx] (invalid)\n",
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i, efi_md_typeattr_format(buf, sizeof(buf), md),
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md->phys_addr, end);
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}
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return false;
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}
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static void __init efi_clean_memmap(void)
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{
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efi_memory_desc_t *out = efi.memmap.map;
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const efi_memory_desc_t *in = out;
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const efi_memory_desc_t *end = efi.memmap.map_end;
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int i, n_removal;
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for (i = n_removal = 0; in < end; i++) {
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if (efi_memmap_entry_valid(in, i)) {
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if (out != in)
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memcpy(out, in, efi.memmap.desc_size);
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out = (void *)out + efi.memmap.desc_size;
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} else {
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n_removal++;
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}
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in = (void *)in + efi.memmap.desc_size;
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}
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if (n_removal > 0) {
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u64 size = efi.memmap.nr_map - n_removal;
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pr_warn("Removing %d invalid memory map entries.\n", n_removal);
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efi_memmap_install(efi.memmap.phys_map, size);
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}
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}
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void __init efi_print_memmap(void)
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{
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efi_memory_desc_t *md;
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int i = 0;
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for_each_efi_memory_desc(md) {
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char buf[64];
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pr_info("mem%02u: %s range=[0x%016llx-0x%016llx] (%lluMB)\n",
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i++, efi_md_typeattr_format(buf, sizeof(buf), md),
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md->phys_addr,
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md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1,
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(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
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}
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}
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static int __init efi_systab_init(void *phys)
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{
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if (efi_enabled(EFI_64BIT)) {
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efi_system_table_64_t *systab64;
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struct efi_setup_data *data = NULL;
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u64 tmp = 0;
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if (efi_setup) {
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data = early_memremap(efi_setup, sizeof(*data));
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if (!data)
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return -ENOMEM;
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}
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systab64 = early_memremap((unsigned long)phys,
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sizeof(*systab64));
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if (systab64 == NULL) {
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pr_err("Couldn't map the system table!\n");
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if (data)
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early_memunmap(data, sizeof(*data));
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return -ENOMEM;
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}
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efi_systab.hdr = systab64->hdr;
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efi_systab.fw_vendor = data ? (unsigned long)data->fw_vendor :
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systab64->fw_vendor;
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tmp |= data ? data->fw_vendor : systab64->fw_vendor;
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efi_systab.fw_revision = systab64->fw_revision;
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efi_systab.con_in_handle = systab64->con_in_handle;
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tmp |= systab64->con_in_handle;
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efi_systab.con_in = systab64->con_in;
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tmp |= systab64->con_in;
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efi_systab.con_out_handle = systab64->con_out_handle;
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tmp |= systab64->con_out_handle;
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efi_systab.con_out = systab64->con_out;
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tmp |= systab64->con_out;
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efi_systab.stderr_handle = systab64->stderr_handle;
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tmp |= systab64->stderr_handle;
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efi_systab.stderr = systab64->stderr;
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tmp |= systab64->stderr;
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efi_systab.runtime = data ?
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(void *)(unsigned long)data->runtime :
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(void *)(unsigned long)systab64->runtime;
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tmp |= data ? data->runtime : systab64->runtime;
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efi_systab.boottime = (void *)(unsigned long)systab64->boottime;
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tmp |= systab64->boottime;
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efi_systab.nr_tables = systab64->nr_tables;
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efi_systab.tables = data ? (unsigned long)data->tables :
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systab64->tables;
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tmp |= data ? data->tables : systab64->tables;
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early_memunmap(systab64, sizeof(*systab64));
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if (data)
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early_memunmap(data, sizeof(*data));
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#ifdef CONFIG_X86_32
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if (tmp >> 32) {
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pr_err("EFI data located above 4GB, disabling EFI.\n");
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return -EINVAL;
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}
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#endif
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} else {
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efi_system_table_32_t *systab32;
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systab32 = early_memremap((unsigned long)phys,
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sizeof(*systab32));
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if (systab32 == NULL) {
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pr_err("Couldn't map the system table!\n");
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return -ENOMEM;
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}
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efi_systab.hdr = systab32->hdr;
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efi_systab.fw_vendor = systab32->fw_vendor;
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efi_systab.fw_revision = systab32->fw_revision;
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efi_systab.con_in_handle = systab32->con_in_handle;
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efi_systab.con_in = systab32->con_in;
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efi_systab.con_out_handle = systab32->con_out_handle;
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efi_systab.con_out = systab32->con_out;
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efi_systab.stderr_handle = systab32->stderr_handle;
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efi_systab.stderr = systab32->stderr;
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efi_systab.runtime = (void *)(unsigned long)systab32->runtime;
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efi_systab.boottime = (void *)(unsigned long)systab32->boottime;
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efi_systab.nr_tables = systab32->nr_tables;
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efi_systab.tables = systab32->tables;
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early_memunmap(systab32, sizeof(*systab32));
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}
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efi.systab = &efi_systab;
|
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/*
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* Verify the EFI Table
|
*/
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if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
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pr_err("System table signature incorrect!\n");
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return -EINVAL;
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}
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if ((efi.systab->hdr.revision >> 16) == 0)
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pr_err("Warning: System table version %d.%02d, expected 1.00 or greater!\n",
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efi.systab->hdr.revision >> 16,
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efi.systab->hdr.revision & 0xffff);
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return 0;
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}
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static int __init efi_runtime_init32(void)
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{
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efi_runtime_services_32_t *runtime;
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runtime = early_memremap((unsigned long)efi.systab->runtime,
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sizeof(efi_runtime_services_32_t));
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if (!runtime) {
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pr_err("Could not map the runtime service table!\n");
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return -ENOMEM;
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}
|
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/*
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* We will only need *early* access to the SetVirtualAddressMap
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* EFI runtime service. All other runtime services will be called
|
* via the virtual mapping.
|
*/
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efi_phys.set_virtual_address_map =
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(efi_set_virtual_address_map_t *)
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(unsigned long)runtime->set_virtual_address_map;
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early_memunmap(runtime, sizeof(efi_runtime_services_32_t));
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return 0;
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}
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static int __init efi_runtime_init64(void)
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{
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efi_runtime_services_64_t *runtime;
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runtime = early_memremap((unsigned long)efi.systab->runtime,
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sizeof(efi_runtime_services_64_t));
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if (!runtime) {
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pr_err("Could not map the runtime service table!\n");
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return -ENOMEM;
|
}
|
|
/*
|
* We will only need *early* access to the SetVirtualAddressMap
|
* EFI runtime service. All other runtime services will be called
|
* via the virtual mapping.
|
*/
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efi_phys.set_virtual_address_map =
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(efi_set_virtual_address_map_t *)
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(unsigned long)runtime->set_virtual_address_map;
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early_memunmap(runtime, sizeof(efi_runtime_services_64_t));
|
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return 0;
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}
|
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static int __init efi_runtime_init(void)
|
{
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int rv;
|
|
/*
|
* 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.
|
*
|
* When EFI_PARAVIRT is in force then we could not map runtime
|
* service memory region because we do not have direct access to it.
|
* However, runtime services are available through proxy functions
|
* (e.g. in case of Xen dom0 EFI implementation they call special
|
* hypercall which executes relevant EFI functions) and that is why
|
* they are always enabled.
|
*/
|
|
if (!efi_enabled(EFI_PARAVIRT)) {
|
if (efi_enabled(EFI_64BIT))
|
rv = efi_runtime_init64();
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else
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rv = efi_runtime_init32();
|
|
if (rv)
|
return rv;
|
}
|
|
set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
|
|
return 0;
|
}
|
|
void __init efi_init(void)
|
{
|
efi_char16_t *c16;
|
char vendor[100] = "unknown";
|
int i = 0;
|
|
#ifdef CONFIG_X86_32
|
if (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_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
|
#else
|
efi_phys.systab = (efi_system_table_t *)
|
(boot_params.efi_info.efi_systab |
|
((__u64)boot_params.efi_info.efi_systab_hi<<32));
|
#endif
|
|
if (efi_systab_init(efi_phys.systab))
|
return;
|
|
efi.config_table = (unsigned long)efi.systab->tables;
|
efi.fw_vendor = (unsigned long)efi.systab->fw_vendor;
|
efi.runtime = (unsigned long)efi.systab->runtime;
|
|
/*
|
* Show what we know for posterity
|
*/
|
c16 = early_memremap_ro(efi.systab->fw_vendor,
|
sizeof(vendor) * sizeof(efi_char16_t));
|
if (c16) {
|
for (i = 0; i < sizeof(vendor) - 1 && c16[i]; ++i)
|
vendor[i] = c16[i];
|
vendor[i] = '\0';
|
early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t));
|
} else {
|
pr_err("Could not map the firmware vendor!\n");
|
}
|
|
pr_info("EFI v%u.%.02u by %s\n",
|
efi.systab->hdr.revision >> 16,
|
efi.systab->hdr.revision & 0xffff, vendor);
|
|
if (efi_reuse_config(efi.systab->tables, efi.systab->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_info("No EFI runtime due to 32/64-bit mismatch with kernel\n");
|
else {
|
if (efi_runtime_disabled() || efi_runtime_init()) {
|
efi_memmap_unmap();
|
return;
|
}
|
}
|
|
efi_clean_memmap();
|
|
if (efi_enabled(EFI_DBG))
|
efi_print_memmap();
|
}
|
|
void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
|
{
|
u64 addr, npages;
|
|
addr = md->virt_addr;
|
npages = md->num_pages;
|
|
memrange_efi_to_native(&addr, &npages);
|
|
if (executable)
|
set_memory_x(addr, npages);
|
else
|
set_memory_nx(addr, npages);
|
}
|
|
void __init runtime_code_page_mkexec(void)
|
{
|
efi_memory_desc_t *md;
|
|
/* Make EFI runtime service code area executable */
|
for_each_efi_memory_desc(md) {
|
if (md->type != EFI_RUNTIME_SERVICES_CODE)
|
continue;
|
|
efi_set_executable(md, true);
|
}
|
}
|
|
void __init efi_memory_uc(u64 addr, unsigned long size)
|
{
|
unsigned long page_shift = 1UL << EFI_PAGE_SHIFT;
|
u64 npages;
|
|
npages = round_up(size, page_shift) / page_shift;
|
memrange_efi_to_native(&addr, &npages);
|
set_memory_uc(addr, npages);
|
}
|
|
void __init old_map_region(efi_memory_desc_t *md)
|
{
|
u64 start_pfn, end_pfn, end;
|
unsigned long size;
|
void *va;
|
|
start_pfn = PFN_DOWN(md->phys_addr);
|
size = md->num_pages << PAGE_SHIFT;
|
end = md->phys_addr + size;
|
end_pfn = PFN_UP(end);
|
|
if (pfn_range_is_mapped(start_pfn, end_pfn)) {
|
va = __va(md->phys_addr);
|
|
if (!(md->attribute & EFI_MEMORY_WB))
|
efi_memory_uc((u64)(unsigned long)va, size);
|
} else
|
va = efi_ioremap(md->phys_addr, size,
|
md->type, md->attribute);
|
|
md->virt_addr = (u64) (unsigned long) va;
|
if (!va)
|
pr_err("ioremap of 0x%llX failed!\n",
|
(unsigned long long)md->phys_addr);
|
}
|
|
/* 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 __init get_systab_virt_addr(efi_memory_desc_t *md)
|
{
|
unsigned long size;
|
u64 end, systab;
|
|
size = md->num_pages << EFI_PAGE_SHIFT;
|
end = md->phys_addr + size;
|
systab = (u64)(unsigned long)efi_phys.systab;
|
if (md->phys_addr <= systab && systab < end) {
|
systab += md->virt_addr - md->phys_addr;
|
efi.systab = (efi_system_table_t *)(unsigned long)systab;
|
}
|
}
|
|
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_OLD_MEMMAP) && 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;
|
|
/*
|
* Map all of RAM so that we can access arguments in the 1:1
|
* mapping when making EFI runtime calls.
|
*/
|
if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_is_native()) {
|
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);
|
get_systab_virt_addr(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;
|
|
efi.systab = NULL;
|
|
/*
|
* We don't do virtual mode, since we don't do runtime services, on
|
* non-native EFI. With efi=old_map, we don't do runtime services in
|
* kexec kernel because in the initial boot something else might
|
* have been mapped at these virtual addresses.
|
*/
|
if (!efi_is_native() || efi_enabled(EFI_OLD_MEMMAP)) {
|
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 */
|
get_systab_virt_addr(md);
|
}
|
|
/*
|
* 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;
|
}
|
|
BUG_ON(!efi.systab);
|
|
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();
|
|
/*
|
* Now that EFI is in virtual mode, update the function
|
* pointers in the runtime service table to the new virtual addresses.
|
*
|
* Call EFI services through wrapper functions.
|
*/
|
efi.runtime_version = efi_systab.hdr.revision;
|
|
efi_native_runtime_setup();
|
|
efi.set_virtual_address_map = NULL;
|
|
if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
|
runtime_code_page_mkexec();
|
#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 old method which used to update that memory descriptor with the
|
* virtual address obtained from ioremap() is still supported when the
|
* kernel is booted with efi=old_map on its command line. Same old
|
* method enabled the runtime services to be called without having to
|
* thunk back into physical mode for every invocation.
|
*
|
* 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;
|
|
efi.systab = NULL;
|
|
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 (WARN_ON(!efi.systab))
|
goto err;
|
|
if (efi_setup_page_tables(pa, 1 << pg_shift))
|
goto err;
|
|
efi_sync_low_kernel_mappings();
|
|
if (efi_is_native()) {
|
status = phys_efi_set_virtual_address_map(
|
efi.memmap.desc_size * count,
|
efi.memmap.desc_size,
|
efi.memmap.desc_version,
|
(efi_memory_desc_t *)pa);
|
} else {
|
status = efi_thunk_set_virtual_address_map(
|
efi_phys.set_virtual_address_map,
|
efi.memmap.desc_size * count,
|
efi.memmap.desc_size,
|
efi.memmap.desc_version,
|
(efi_memory_desc_t *)pa);
|
}
|
|
if (status != EFI_SUCCESS) {
|
pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n",
|
status);
|
goto err;
|
}
|
|
/*
|
* Now that EFI is in virtual mode, update the function
|
* pointers in the runtime service table to the new virtual addresses.
|
*
|
* Call EFI services through wrapper functions.
|
*/
|
efi.runtime_version = efi_systab.hdr.revision;
|
|
if (efi_is_native())
|
efi_native_runtime_setup();
|
else
|
efi_thunk_runtime_setup();
|
|
efi.set_virtual_address_map = NULL;
|
|
/*
|
* 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;
|
|
if (efi_setup)
|
kexec_enter_virtual_mode();
|
else
|
__efi_enter_virtual_mode();
|
|
efi_dump_pagetable();
|
}
|
|
static int __init arch_parse_efi_cmdline(char *str)
|
{
|
if (!str) {
|
pr_warn("need at least one option\n");
|
return -EINVAL;
|
}
|
|
if (parse_option_str(str, "old_map"))
|
set_bit(EFI_OLD_MEMMAP, &efi.flags);
|
|
return 0;
|
}
|
early_param("efi", arch_parse_efi_cmdline);
|
