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-rw-r--r--arch/arm64/kernel/efi.c334
1 files changed, 17 insertions, 317 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index 4eeb17198..b6abc852f 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -11,317 +11,34 @@
*
*/
-#include <linux/atomic.h>
#include <linux/dmi.h>
#include <linux/efi.h>
-#include <linux/export.h>
-#include <linux/memblock.h>
-#include <linux/mm_types.h>
-#include <linux/bootmem.h>
-#include <linux/of.h>
-#include <linux/of_fdt.h>
-#include <linux/preempt.h>
-#include <linux/rbtree.h>
-#include <linux/rwsem.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
+#include <linux/init.h>
-#include <asm/cacheflush.h>
#include <asm/efi.h>
-#include <asm/tlbflush.h>
-#include <asm/mmu_context.h>
-#include <asm/mmu.h>
-#include <asm/pgtable.h>
-struct efi_memory_map memmap;
-
-static u64 efi_system_table;
-
-static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
-
-static struct mm_struct efi_mm = {
- .mm_rb = RB_ROOT,
- .pgd = efi_pgd,
- .mm_users = ATOMIC_INIT(2),
- .mm_count = ATOMIC_INIT(1),
- .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
- .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
- .mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
-};
-
-static int __init is_normal_ram(efi_memory_desc_t *md)
-{
- if (md->attribute & EFI_MEMORY_WB)
- return 1;
- return 0;
-}
-
-/*
- * Translate a EFI virtual address into a physical address: this is necessary,
- * as some data members of the EFI system table are virtually remapped after
- * SetVirtualAddressMap() has been called.
- */
-static phys_addr_t efi_to_phys(unsigned long addr)
+int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
{
- efi_memory_desc_t *md;
-
- for_each_efi_memory_desc(&memmap, md) {
- if (!(md->attribute & EFI_MEMORY_RUNTIME))
- continue;
- if (md->virt_addr == 0)
- /* no virtual mapping has been installed by the stub */
- break;
- if (md->virt_addr <= addr &&
- (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT))
- return md->phys_addr + addr - md->virt_addr;
- }
- return addr;
-}
-
-static int __init uefi_init(void)
-{
- efi_char16_t *c16;
- void *config_tables;
- u64 table_size;
- char vendor[100] = "unknown";
- int i, retval;
-
- efi.systab = early_memremap(efi_system_table,
- sizeof(efi_system_table_t));
- if (efi.systab == NULL) {
- pr_warn("Unable to map EFI system table.\n");
- return -ENOMEM;
- }
-
- set_bit(EFI_BOOT, &efi.flags);
- set_bit(EFI_64BIT, &efi.flags);
+ pteval_t prot_val;
/*
- * Verify the EFI Table
+ * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
+ * executable, everything else can be mapped with the XN bits
+ * set.
*/
- if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
- pr_err("System table signature incorrect\n");
- retval = -EINVAL;
- goto out;
- }
- if ((efi.systab->hdr.revision >> 16) < 2)
- pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
- efi.systab->hdr.revision >> 16,
- efi.systab->hdr.revision & 0xffff);
-
- /* Show what we know for posterity */
- c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor),
- sizeof(vendor) * sizeof(efi_char16_t));
- if (c16) {
- for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
- vendor[i] = c16[i];
- vendor[i] = '\0';
- early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t));
- }
-
- pr_info("EFI v%u.%.02u by %s\n",
- efi.systab->hdr.revision >> 16,
- efi.systab->hdr.revision & 0xffff, vendor);
-
- table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
- config_tables = early_memremap(efi_to_phys(efi.systab->tables),
- table_size);
- if (config_tables == NULL) {
- pr_warn("Unable to map EFI config table array.\n");
- retval = -ENOMEM;
- goto out;
- }
- retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables,
- sizeof(efi_config_table_64_t), NULL);
-
- early_memunmap(config_tables, table_size);
-out:
- early_memunmap(efi.systab, sizeof(efi_system_table_t));
- return retval;
-}
-
-/*
- * Return true for RAM regions we want to permanently reserve.
- */
-static __init int is_reserve_region(efi_memory_desc_t *md)
-{
- 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:
- case EFI_PERSISTENT_MEMORY:
- return 0;
- default:
- break;
- }
- return is_normal_ram(md);
-}
-
-static __init void reserve_regions(void)
-{
- efi_memory_desc_t *md;
- u64 paddr, npages, size;
-
- if (efi_enabled(EFI_DBG))
- pr_info("Processing EFI memory map:\n");
-
- for_each_efi_memory_desc(&memmap, md) {
- paddr = md->phys_addr;
- npages = md->num_pages;
-
- if (efi_enabled(EFI_DBG)) {
- char buf[64];
-
- pr_info(" 0x%012llx-0x%012llx %s",
- paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
- efi_md_typeattr_format(buf, sizeof(buf), md));
- }
-
- memrange_efi_to_native(&paddr, &npages);
- size = npages << PAGE_SHIFT;
-
- if (is_normal_ram(md))
- early_init_dt_add_memory_arch(paddr, size);
-
- if (is_reserve_region(md)) {
- memblock_reserve(paddr, size);
- if (efi_enabled(EFI_DBG))
- pr_cont("*");
- }
-
- if (efi_enabled(EFI_DBG))
- pr_cont("\n");
- }
-
- set_bit(EFI_MEMMAP, &efi.flags);
-}
-
-void __init efi_init(void)
-{
- struct efi_fdt_params params;
-
- /* Grab UEFI information placed in FDT by stub */
- if (!efi_get_fdt_params(&params))
- return;
-
- efi_system_table = params.system_table;
-
- memblock_reserve(params.mmap & PAGE_MASK,
- PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK)));
- memmap.phys_map = params.mmap;
- memmap.map = early_memremap(params.mmap, params.mmap_size);
- if (memmap.map == NULL) {
- /*
- * If we are booting via UEFI, the UEFI memory map is the only
- * description of memory we have, so there is little point in
- * proceeding if we cannot access it.
- */
- panic("Unable to map EFI memory map.\n");
- }
- memmap.map_end = memmap.map + params.mmap_size;
- memmap.desc_size = params.desc_size;
- memmap.desc_version = params.desc_ver;
-
- if (uefi_init() < 0)
- return;
-
- reserve_regions();
- early_memunmap(memmap.map, params.mmap_size);
-}
-
-static bool __init efi_virtmap_init(void)
-{
- efi_memory_desc_t *md;
-
- init_new_context(NULL, &efi_mm);
-
- for_each_efi_memory_desc(&memmap, md) {
- pgprot_t prot;
-
- if (!(md->attribute & EFI_MEMORY_RUNTIME))
- continue;
- if (md->virt_addr == 0)
- return false;
-
- pr_info(" EFI remap 0x%016llx => %p\n",
- md->phys_addr, (void *)md->virt_addr);
-
- /*
- * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
- * executable, everything else can be mapped with the XN bits
- * set.
- */
- if (!is_normal_ram(md))
- prot = __pgprot(PROT_DEVICE_nGnRE);
- else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
- !PAGE_ALIGNED(md->phys_addr))
- prot = PAGE_KERNEL_EXEC;
- else
- prot = PAGE_KERNEL;
-
- create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr,
- md->num_pages << EFI_PAGE_SHIFT,
- __pgprot(pgprot_val(prot) | PTE_NG));
- }
- return true;
-}
-
-/*
- * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
- * non-early mapping of the UEFI system table and virtual mappings for all
- * EFI_MEMORY_RUNTIME regions.
- */
-static int __init arm64_enable_runtime_services(void)
-{
- u64 mapsize;
-
- if (!efi_enabled(EFI_BOOT)) {
- pr_info("EFI services will not be available.\n");
- return 0;
- }
-
- if (efi_runtime_disabled()) {
- pr_info("EFI runtime services will be disabled.\n");
- return 0;
- }
-
- pr_info("Remapping and enabling EFI services.\n");
-
- mapsize = memmap.map_end - memmap.map;
- memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
- mapsize);
- if (!memmap.map) {
- pr_err("Failed to remap EFI memory map\n");
- return -ENOMEM;
- }
- memmap.map_end = memmap.map + mapsize;
- efi.memmap = &memmap;
-
- efi.systab = (__force void *)ioremap_cache(efi_system_table,
- sizeof(efi_system_table_t));
- if (!efi.systab) {
- pr_err("Failed to remap EFI System Table\n");
- return -ENOMEM;
- }
- set_bit(EFI_SYSTEM_TABLES, &efi.flags);
-
- if (!efi_virtmap_init()) {
- pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
- return -ENOMEM;
- }
-
- /* Set up runtime services function pointers */
- efi_native_runtime_setup();
- set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
-
- efi.runtime_version = efi.systab->hdr.revision;
-
+ if ((md->attribute & EFI_MEMORY_WB) == 0)
+ prot_val = PROT_DEVICE_nGnRE;
+ else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
+ !PAGE_ALIGNED(md->phys_addr))
+ prot_val = pgprot_val(PAGE_KERNEL_EXEC);
+ else
+ prot_val = pgprot_val(PAGE_KERNEL);
+
+ create_pgd_mapping(mm, md->phys_addr, md->virt_addr,
+ md->num_pages << EFI_PAGE_SHIFT,
+ __pgprot(prot_val | PTE_NG));
return 0;
}
-early_initcall(arm64_enable_runtime_services);
static int __init arm64_dmi_init(void)
{
@@ -337,23 +54,6 @@ static int __init arm64_dmi_init(void)
}
core_initcall(arm64_dmi_init);
-static void efi_set_pgd(struct mm_struct *mm)
-{
- switch_mm(NULL, mm, NULL);
-}
-
-void efi_virtmap_load(void)
-{
- preempt_disable();
- efi_set_pgd(&efi_mm);
-}
-
-void efi_virtmap_unload(void)
-{
- efi_set_pgd(current->active_mm);
- preempt_enable();
-}
-
/*
* UpdateCapsule() depends on the system being shutdown via
* ResetSystem().