![Sai Praneeth](/assets/img/avatar_default.png)
Presently, only ARM uses mm_struct to manage EFI page tables and EFI runtime region mappings. As this is the preferred approach, let's make this data structure common across architectures. Specially, for x86, using this data structure improves code maintainability and readability. Tested-by: Bhupesh Sharma <bhsharma@redhat.com> [ardb: don't #include the world to get a declaration of struct mm_struct] Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Ricardo Neri <ricardo.neri@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180312084500.10764-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
176 lines
3.9 KiB
C
176 lines
3.9 KiB
C
/*
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* Extensible Firmware Interface
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*
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* Based on Extensible Firmware Interface Specification version 2.4
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*
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* Copyright (C) 2013, 2014 Linaro Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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*/
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#include <linux/dmi.h>
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#include <linux/efi.h>
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#include <linux/io.h>
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#include <linux/memblock.h>
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#include <linux/mm_types.h>
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#include <linux/preempt.h>
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#include <linux/rbtree.h>
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#include <linux/rwsem.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <asm/cacheflush.h>
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#include <asm/efi.h>
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#include <asm/mmu.h>
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#include <asm/pgalloc.h>
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#include <asm/pgtable.h>
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extern u64 efi_system_table;
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#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS
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#include <asm/ptdump.h>
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static struct ptdump_info efi_ptdump_info = {
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.mm = &efi_mm,
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.markers = (struct addr_marker[]){
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{ 0, "UEFI runtime start" },
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{ TASK_SIZE_64, "UEFI runtime end" }
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},
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.base_addr = 0,
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};
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static int __init ptdump_init(void)
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{
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if (!efi_enabled(EFI_RUNTIME_SERVICES))
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return 0;
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return ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
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}
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device_initcall(ptdump_init);
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#endif
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static bool __init efi_virtmap_init(void)
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{
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efi_memory_desc_t *md;
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bool systab_found;
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efi_mm.pgd = pgd_alloc(&efi_mm);
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mm_init_cpumask(&efi_mm);
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init_new_context(NULL, &efi_mm);
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systab_found = false;
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for_each_efi_memory_desc(md) {
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phys_addr_t phys = md->phys_addr;
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int ret;
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if (!(md->attribute & EFI_MEMORY_RUNTIME))
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continue;
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if (md->virt_addr == 0)
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return false;
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ret = efi_create_mapping(&efi_mm, md);
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if (ret) {
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pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
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&phys, ret);
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return false;
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}
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/*
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* If this entry covers the address of the UEFI system table,
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* calculate and record its virtual address.
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*/
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if (efi_system_table >= phys &&
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efi_system_table < phys + (md->num_pages * EFI_PAGE_SIZE)) {
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efi.systab = (void *)(unsigned long)(efi_system_table -
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phys + md->virt_addr);
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systab_found = true;
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}
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}
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if (!systab_found) {
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pr_err("No virtual mapping found for the UEFI System Table\n");
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return false;
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}
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if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
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return false;
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return true;
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}
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/*
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* Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
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* non-early mapping of the UEFI system table and virtual mappings for all
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* EFI_MEMORY_RUNTIME regions.
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*/
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static int __init arm_enable_runtime_services(void)
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{
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u64 mapsize;
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if (!efi_enabled(EFI_BOOT)) {
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pr_info("EFI services will not be available.\n");
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return 0;
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}
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if (efi_runtime_disabled()) {
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pr_info("EFI runtime services will be disabled.\n");
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return 0;
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}
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if (efi_enabled(EFI_RUNTIME_SERVICES)) {
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pr_info("EFI runtime services access via paravirt.\n");
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return 0;
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}
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pr_info("Remapping and enabling EFI services.\n");
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mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
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if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
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pr_err("Failed to remap EFI memory map\n");
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return -ENOMEM;
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}
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if (!efi_virtmap_init()) {
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pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
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return -ENOMEM;
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}
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/* Set up runtime services function pointers */
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efi_native_runtime_setup();
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set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
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return 0;
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}
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early_initcall(arm_enable_runtime_services);
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void efi_virtmap_load(void)
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{
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preempt_disable();
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efi_set_pgd(&efi_mm);
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}
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void efi_virtmap_unload(void)
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{
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efi_set_pgd(current->active_mm);
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preempt_enable();
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}
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static int __init arm_dmi_init(void)
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{
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/*
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* On arm64/ARM, DMI depends on UEFI, and dmi_scan_machine() needs to
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* be called early because dmi_id_init(), which is an arch_initcall
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* itself, depends on dmi_scan_machine() having been called already.
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*/
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dmi_scan_machine();
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if (dmi_available)
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dmi_set_dump_stack_arch_desc();
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return 0;
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}
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core_initcall(arm_dmi_init);
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