edd= [EDD]
Format: {"off" | "on" | "skip[mbr]"}
+ efi= [EFI]
+ Format: { "old_map" }
+ old_map [X86-64]: switch to the old ioremap-based EFI
+ runtime services mapping. 32-bit still uses this one by
+ default.
+
efi_no_storage_paranoia [EFI; X86]
Using this parameter you can use more than 50% of
your efi variable storage. Use this parameter only if
Current X86-64 implementations only support 40 bits of address space,
but we support up to 46 bits. This expands into MBZ space in the page tables.
+->trampoline_pgd:
+
+We map EFI runtime services in the aforementioned PGD in the virtual
+range of 64Gb (arbitrarily set, can be raised if needed)
+
+0xffffffef00000000 - 0xffffffff00000000
+
-Andi Kleen, Jul 2004
#ifndef _ASM_X86_EFI_H
#define _ASM_X86_EFI_H
+/*
+ * We map the EFI regions needed for runtime services non-contiguously,
+ * with preserved alignment on virtual addresses starting from -4G down
+ * for a total max space of 64G. This way, we provide for stable runtime
+ * services addresses across kernels so that a kexec'd kernel can still
+ * use them.
+ *
+ * This is the main reason why we're doing stable VA mappings for RT
+ * services.
+ *
+ * This flag is used in conjuction with a chicken bit called
+ * "efi=old_map" which can be used as a fallback to the old runtime
+ * services mapping method in case there's some b0rkage with a
+ * particular EFI implementation (haha, it is hard to hold up the
+ * sarcasm here...).
+ */
+#define EFI_OLD_MEMMAP EFI_ARCH_1
+
#ifdef CONFIG_X86_32
#define EFI_LOADER_SIGNATURE "EL32"
efi_call6((f), (u64)(a1), (u64)(a2), (u64)(a3), \
(u64)(a4), (u64)(a5), (u64)(a6))
+#define _efi_call_virtX(x, f, ...) \
+({ \
+ efi_status_t __s; \
+ \
+ efi_sync_low_kernel_mappings(); \
+ preempt_disable(); \
+ __s = efi_call##x((void *)efi.systab->runtime->f, __VA_ARGS__); \
+ preempt_enable(); \
+ __s; \
+})
+
#define efi_call_virt0(f) \
- efi_call0((efi.systab->runtime->f))
-#define efi_call_virt1(f, a1) \
- efi_call1((efi.systab->runtime->f), (u64)(a1))
-#define efi_call_virt2(f, a1, a2) \
- efi_call2((efi.systab->runtime->f), (u64)(a1), (u64)(a2))
-#define efi_call_virt3(f, a1, a2, a3) \
- efi_call3((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
- (u64)(a3))
-#define efi_call_virt4(f, a1, a2, a3, a4) \
- efi_call4((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
- (u64)(a3), (u64)(a4))
-#define efi_call_virt5(f, a1, a2, a3, a4, a5) \
- efi_call5((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
- (u64)(a3), (u64)(a4), (u64)(a5))
-#define efi_call_virt6(f, a1, a2, a3, a4, a5, a6) \
- efi_call6((efi.systab->runtime->f), (u64)(a1), (u64)(a2), \
- (u64)(a3), (u64)(a4), (u64)(a5), (u64)(a6))
+ _efi_call_virtX(0, f)
+#define efi_call_virt1(f, a1) \
+ _efi_call_virtX(1, f, (u64)(a1))
+#define efi_call_virt2(f, a1, a2) \
+ _efi_call_virtX(2, f, (u64)(a1), (u64)(a2))
+#define efi_call_virt3(f, a1, a2, a3) \
+ _efi_call_virtX(3, f, (u64)(a1), (u64)(a2), (u64)(a3))
+#define efi_call_virt4(f, a1, a2, a3, a4) \
+ _efi_call_virtX(4, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4))
+#define efi_call_virt5(f, a1, a2, a3, a4, a5) \
+ _efi_call_virtX(5, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4), (u64)(a5))
+#define efi_call_virt6(f, a1, a2, a3, a4, a5, a6) \
+ _efi_call_virtX(6, f, (u64)(a1), (u64)(a2), (u64)(a3), (u64)(a4), (u64)(a5), (u64)(a6))
extern void __iomem *efi_ioremap(unsigned long addr, unsigned long size,
u32 type, u64 attribute);
extern int add_efi_memmap;
extern unsigned long x86_efi_facility;
+extern struct efi_scratch efi_scratch;
extern void efi_set_executable(efi_memory_desc_t *md, bool executable);
extern int efi_memblock_x86_reserve_range(void);
extern void efi_call_phys_prelog(void);
extern void efi_call_phys_epilog(void);
extern void efi_unmap_memmap(void);
extern void efi_memory_uc(u64 addr, unsigned long size);
+extern void __init efi_map_region(efi_memory_desc_t *md);
+extern void efi_sync_low_kernel_mappings(void);
+extern void efi_setup_page_tables(void);
+extern void __init old_map_region(efi_memory_desc_t *md);
#ifdef CONFIG_EFI
*/
extern pte_t *lookup_address(unsigned long address, unsigned int *level);
extern phys_addr_t slow_virt_to_phys(void *__address);
-
+extern int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
+ unsigned numpages, unsigned long page_flags);
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PGTABLE_DEFS_H */
*/
struct cpa_data {
unsigned long *vaddr;
+ pgd_t *pgd;
pgprot_t mask_set;
pgprot_t mask_clr;
int numpages;
return prot;
}
-/*
- * Lookup the page table entry for a virtual address. Return a pointer
- * to the entry and the level of the mapping.
- *
- * Note: We return pud and pmd either when the entry is marked large
- * or when the present bit is not set. Otherwise we would return a
- * pointer to a nonexisting mapping.
- */
-pte_t *lookup_address(unsigned long address, unsigned int *level)
+static pte_t *__lookup_address_in_pgd(pgd_t *pgd, unsigned long address,
+ unsigned int *level)
{
- pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
pmd_t *pmd;
return pte_offset_kernel(pmd, address);
}
+
+/*
+ * Lookup the page table entry for a virtual address. Return a pointer
+ * to the entry and the level of the mapping.
+ *
+ * Note: We return pud and pmd either when the entry is marked large
+ * or when the present bit is not set. Otherwise we would return a
+ * pointer to a nonexisting mapping.
+ */
+pte_t *lookup_address(unsigned long address, unsigned int *level)
+{
+ return __lookup_address_in_pgd(pgd_offset_k(address), address, level);
+}
EXPORT_SYMBOL_GPL(lookup_address);
+static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address,
+ unsigned int *level)
+{
+ if (cpa->pgd)
+ return __lookup_address_in_pgd(cpa->pgd + pgd_index(address),
+ address, level);
+
+ return lookup_address(address, level);
+}
+
/*
* This is necessary because __pa() does not work on some
* kinds of memory, like vmalloc() or the alloc_remap()
* Check for races, another CPU might have split this page
* up already:
*/
- tmp = lookup_address(address, &level);
+ tmp = _lookup_address_cpa(cpa, address, &level);
if (tmp != kpte)
goto out_unlock;
}
static int
-__split_large_page(pte_t *kpte, unsigned long address, struct page *base)
+__split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address,
+ struct page *base)
{
pte_t *pbase = (pte_t *)page_address(base);
unsigned long pfn, pfninc = 1;
* Check for races, another CPU might have split this page
* up for us already:
*/
- tmp = lookup_address(address, &level);
+ tmp = _lookup_address_cpa(cpa, address, &level);
if (tmp != kpte) {
spin_unlock(&pgd_lock);
return 1;
return 0;
}
-static int split_large_page(pte_t *kpte, unsigned long address)
+static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
+ unsigned long address)
{
struct page *base;
if (!base)
return -ENOMEM;
- if (__split_large_page(kpte, address, base))
+ if (__split_large_page(cpa, kpte, address, base))
__free_page(base);
return 0;
}
+static bool try_to_free_pte_page(pte_t *pte)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ if (!pte_none(pte[i]))
+ return false;
+
+ free_page((unsigned long)pte);
+ return true;
+}
+
+static bool try_to_free_pmd_page(pmd_t *pmd)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PMD; i++)
+ if (!pmd_none(pmd[i]))
+ return false;
+
+ free_page((unsigned long)pmd);
+ return true;
+}
+
+static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
+{
+ pte_t *pte = pte_offset_kernel(pmd, start);
+
+ while (start < end) {
+ set_pte(pte, __pte(0));
+
+ start += PAGE_SIZE;
+ pte++;
+ }
+
+ if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
+ pmd_clear(pmd);
+ return true;
+ }
+ return false;
+}
+
+static void __unmap_pmd_range(pud_t *pud, pmd_t *pmd,
+ unsigned long start, unsigned long end)
+{
+ if (unmap_pte_range(pmd, start, end))
+ if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+ pud_clear(pud);
+}
+
+static void unmap_pmd_range(pud_t *pud, unsigned long start, unsigned long end)
+{
+ pmd_t *pmd = pmd_offset(pud, start);
+
+ /*
+ * Not on a 2MB page boundary?
+ */
+ if (start & (PMD_SIZE - 1)) {
+ unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
+ unsigned long pre_end = min_t(unsigned long, end, next_page);
+
+ __unmap_pmd_range(pud, pmd, start, pre_end);
+
+ start = pre_end;
+ pmd++;
+ }
+
+ /*
+ * Try to unmap in 2M chunks.
+ */
+ while (end - start >= PMD_SIZE) {
+ if (pmd_large(*pmd))
+ pmd_clear(pmd);
+ else
+ __unmap_pmd_range(pud, pmd, start, start + PMD_SIZE);
+
+ start += PMD_SIZE;
+ pmd++;
+ }
+
+ /*
+ * 4K leftovers?
+ */
+ if (start < end)
+ return __unmap_pmd_range(pud, pmd, start, end);
+
+ /*
+ * Try again to free the PMD page if haven't succeeded above.
+ */
+ if (!pud_none(*pud))
+ if (try_to_free_pmd_page((pmd_t *)pud_page_vaddr(*pud)))
+ pud_clear(pud);
+}
+
+static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end)
+{
+ pud_t *pud = pud_offset(pgd, start);
+
+ /*
+ * Not on a GB page boundary?
+ */
+ if (start & (PUD_SIZE - 1)) {
+ unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
+ unsigned long pre_end = min_t(unsigned long, end, next_page);
+
+ unmap_pmd_range(pud, start, pre_end);
+
+ start = pre_end;
+ pud++;
+ }
+
+ /*
+ * Try to unmap in 1G chunks?
+ */
+ while (end - start >= PUD_SIZE) {
+
+ if (pud_large(*pud))
+ pud_clear(pud);
+ else
+ unmap_pmd_range(pud, start, start + PUD_SIZE);
+
+ start += PUD_SIZE;
+ pud++;
+ }
+
+ /*
+ * 2M leftovers?
+ */
+ if (start < end)
+ unmap_pmd_range(pud, start, end);
+
+ /*
+ * No need to try to free the PUD page because we'll free it in
+ * populate_pgd's error path
+ */
+}
+
+static int alloc_pte_page(pmd_t *pmd)
+{
+ pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK);
+ if (!pte)
+ return -1;
+
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
+ return 0;
+}
+
+static int alloc_pmd_page(pud_t *pud)
+{
+ pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK);
+ if (!pmd)
+ return -1;
+
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+ return 0;
+}
+
+static void populate_pte(struct cpa_data *cpa,
+ unsigned long start, unsigned long end,
+ unsigned num_pages, pmd_t *pmd, pgprot_t pgprot)
+{
+ pte_t *pte;
+
+ pte = pte_offset_kernel(pmd, start);
+
+ while (num_pages-- && start < end) {
+
+ /* deal with the NX bit */
+ if (!(pgprot_val(pgprot) & _PAGE_NX))
+ cpa->pfn &= ~_PAGE_NX;
+
+ set_pte(pte, pfn_pte(cpa->pfn >> PAGE_SHIFT, pgprot));
+
+ start += PAGE_SIZE;
+ cpa->pfn += PAGE_SIZE;
+ pte++;
+ }
+}
+
+static int populate_pmd(struct cpa_data *cpa,
+ unsigned long start, unsigned long end,
+ unsigned num_pages, pud_t *pud, pgprot_t pgprot)
+{
+ unsigned int cur_pages = 0;
+ pmd_t *pmd;
+
+ /*
+ * Not on a 2M boundary?
+ */
+ if (start & (PMD_SIZE - 1)) {
+ unsigned long pre_end = start + (num_pages << PAGE_SHIFT);
+ unsigned long next_page = (start + PMD_SIZE) & PMD_MASK;
+
+ pre_end = min_t(unsigned long, pre_end, next_page);
+ cur_pages = (pre_end - start) >> PAGE_SHIFT;
+ cur_pages = min_t(unsigned int, num_pages, cur_pages);
+
+ /*
+ * Need a PTE page?
+ */
+ pmd = pmd_offset(pud, start);
+ if (pmd_none(*pmd))
+ if (alloc_pte_page(pmd))
+ return -1;
+
+ populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
+
+ start = pre_end;
+ }
+
+ /*
+ * We mapped them all?
+ */
+ if (num_pages == cur_pages)
+ return cur_pages;
+
+ while (end - start >= PMD_SIZE) {
+
+ /*
+ * We cannot use a 1G page so allocate a PMD page if needed.
+ */
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ pmd = pmd_offset(pud, start);
+
+ set_pmd(pmd, __pmd(cpa->pfn | _PAGE_PSE | massage_pgprot(pgprot)));
+
+ start += PMD_SIZE;
+ cpa->pfn += PMD_SIZE;
+ cur_pages += PMD_SIZE >> PAGE_SHIFT;
+ }
+
+ /*
+ * Map trailing 4K pages.
+ */
+ if (start < end) {
+ pmd = pmd_offset(pud, start);
+ if (pmd_none(*pmd))
+ if (alloc_pte_page(pmd))
+ return -1;
+
+ populate_pte(cpa, start, end, num_pages - cur_pages,
+ pmd, pgprot);
+ }
+ return num_pages;
+}
+
+static int populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
+ pgprot_t pgprot)
+{
+ pud_t *pud;
+ unsigned long end;
+ int cur_pages = 0;
+
+ end = start + (cpa->numpages << PAGE_SHIFT);
+
+ /*
+ * Not on a Gb page boundary? => map everything up to it with
+ * smaller pages.
+ */
+ if (start & (PUD_SIZE - 1)) {
+ unsigned long pre_end;
+ unsigned long next_page = (start + PUD_SIZE) & PUD_MASK;
+
+ pre_end = min_t(unsigned long, end, next_page);
+ cur_pages = (pre_end - start) >> PAGE_SHIFT;
+ cur_pages = min_t(int, (int)cpa->numpages, cur_pages);
+
+ pud = pud_offset(pgd, start);
+
+ /*
+ * Need a PMD page?
+ */
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ cur_pages = populate_pmd(cpa, start, pre_end, cur_pages,
+ pud, pgprot);
+ if (cur_pages < 0)
+ return cur_pages;
+
+ start = pre_end;
+ }
+
+ /* We mapped them all? */
+ if (cpa->numpages == cur_pages)
+ return cur_pages;
+
+ pud = pud_offset(pgd, start);
+
+ /*
+ * Map everything starting from the Gb boundary, possibly with 1G pages
+ */
+ while (end - start >= PUD_SIZE) {
+ set_pud(pud, __pud(cpa->pfn | _PAGE_PSE | massage_pgprot(pgprot)));
+
+ start += PUD_SIZE;
+ cpa->pfn += PUD_SIZE;
+ cur_pages += PUD_SIZE >> PAGE_SHIFT;
+ pud++;
+ }
+
+ /* Map trailing leftover */
+ if (start < end) {
+ int tmp;
+
+ pud = pud_offset(pgd, start);
+ if (pud_none(*pud))
+ if (alloc_pmd_page(pud))
+ return -1;
+
+ tmp = populate_pmd(cpa, start, end, cpa->numpages - cur_pages,
+ pud, pgprot);
+ if (tmp < 0)
+ return cur_pages;
+
+ cur_pages += tmp;
+ }
+ return cur_pages;
+}
+
+/*
+ * Restrictions for kernel page table do not necessarily apply when mapping in
+ * an alternate PGD.
+ */
+static int populate_pgd(struct cpa_data *cpa, unsigned long addr)
+{
+ pgprot_t pgprot = __pgprot(_KERNPG_TABLE);
+ bool allocd_pgd = false;
+ pgd_t *pgd_entry;
+ pud_t *pud = NULL; /* shut up gcc */
+ int ret;
+
+ pgd_entry = cpa->pgd + pgd_index(addr);
+
+ /*
+ * Allocate a PUD page and hand it down for mapping.
+ */
+ if (pgd_none(*pgd_entry)) {
+ pud = (pud_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK);
+ if (!pud)
+ return -1;
+
+ set_pgd(pgd_entry, __pgd(__pa(pud) | _KERNPG_TABLE));
+ allocd_pgd = true;
+ }
+
+ pgprot_val(pgprot) &= ~pgprot_val(cpa->mask_clr);
+ pgprot_val(pgprot) |= pgprot_val(cpa->mask_set);
+
+ ret = populate_pud(cpa, addr, pgd_entry, pgprot);
+ if (ret < 0) {
+ unmap_pud_range(pgd_entry, addr,
+ addr + (cpa->numpages << PAGE_SHIFT));
+
+ if (allocd_pgd) {
+ /*
+ * If I allocated this PUD page, I can just as well
+ * free it in this error path.
+ */
+ pgd_clear(pgd_entry);
+ free_page((unsigned long)pud);
+ }
+ return ret;
+ }
+ cpa->numpages = ret;
+ return 0;
+}
+
static int __cpa_process_fault(struct cpa_data *cpa, unsigned long vaddr,
int primary)
{
+ if (cpa->pgd)
+ return populate_pgd(cpa, vaddr);
+
/*
* Ignore all non primary paths.
*/
else
address = *cpa->vaddr;
repeat:
- kpte = lookup_address(address, &level);
+ kpte = _lookup_address_cpa(cpa, address, &level);
if (!kpte)
return __cpa_process_fault(cpa, address, primary);
/*
* We have to split the large page:
*/
- err = split_large_page(kpte, address);
+ err = split_large_page(cpa, kpte, address);
if (!err) {
/*
* Do a global flush tlb after splitting the large page
int ret, cache, checkalias;
unsigned long baddr = 0;
+ memset(&cpa, 0, sizeof(cpa));
+
/*
* Check, if we are requested to change a not supported
* feature:
{
unsigned long tempaddr = (unsigned long) page_address(page);
struct cpa_data cpa = { .vaddr = &tempaddr,
+ .pgd = NULL,
.numpages = numpages,
.mask_set = __pgprot(_PAGE_PRESENT | _PAGE_RW),
.mask_clr = __pgprot(0),
{
unsigned long tempaddr = (unsigned long) page_address(page);
struct cpa_data cpa = { .vaddr = &tempaddr,
+ .pgd = NULL,
.numpages = numpages,
.mask_set = __pgprot(0),
.mask_clr = __pgprot(_PAGE_PRESENT | _PAGE_RW),
#endif /* CONFIG_DEBUG_PAGEALLOC */
+int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
+ unsigned numpages, unsigned long page_flags)
+{
+ int retval = -EINVAL;
+
+ struct cpa_data cpa = {
+ .vaddr = &address,
+ .pfn = pfn,
+ .pgd = pgd,
+ .numpages = numpages,
+ .mask_set = __pgprot(0),
+ .mask_clr = __pgprot(0),
+ .flags = 0,
+ };
+
+ if (!(__supported_pte_mask & _PAGE_NX))
+ goto out;
+
+ if (!(page_flags & _PAGE_NX))
+ cpa.mask_clr = __pgprot(_PAGE_NX);
+
+ cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
+
+ retval = __change_page_attr_set_clr(&cpa, 0);
+ __flush_tlb_all();
+
+out:
+ return retval;
+}
+
/*
* The testcases use internal knowledge of the implementation that shouldn't
* be exposed to the rest of the kernel. Include these directly here.
* 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
#include <asm/x86_init.h>
#include <asm/rtc.h>
-#define EFI_DEBUG 1
+#define EFI_DEBUG
#define EFI_MIN_RESERVE 5120
return 0;
}
-#if EFI_DEBUG
static void __init print_efi_memmap(void)
{
+#ifdef EFI_DEBUG
efi_memory_desc_t *md;
void *p;
int i;
md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
(md->num_pages >> (20 - EFI_PAGE_SHIFT)));
}
-}
#endif /* EFI_DEBUG */
+}
void __init efi_reserve_boot_services(void)
{
x86_platform.set_wallclock = efi_set_rtc_mmss;
}
#endif
-
-#if EFI_DEBUG
print_efi_memmap();
-#endif
}
void __init efi_late_init(void)
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);
+}
+
/*
* This function will switch the EFI runtime services to virtual mode.
- * Essentially, look through the EFI memmap and map every region that
- * has the runtime attribute bit set in its memory descriptor and update
- * that memory descriptor with the virtual address obtained from ioremap().
- * This enables the runtime services to be called without having to
+ * Essentially, we look through the EFI memmap and map every region that
+ * has the runtime attribute bit set in its memory descriptor into the
+ * ->trampoline_pgd page table using a top-down VA allocation scheme.
+ *
+ * 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 PGDs of the
+ * kernel page table into ->trampoline_pgd prior to each call.
*/
void __init efi_enter_virtual_mode(void)
{
efi_memory_desc_t *md, *prev_md = NULL;
- efi_status_t status;
+ void *p, *new_memmap = NULL;
unsigned long size;
- u64 end, systab, start_pfn, end_pfn;
- void *p, *va, *new_memmap = NULL;
+ efi_status_t status;
+ u64 end, systab;
int count = 0;
efi.systab = NULL;
* We don't do virtual mode, since we don't do runtime services, on
* non-native EFI
*/
-
if (!efi_is_native()) {
efi_unmap_memmap();
return;
continue;
}
prev_md = md;
+
}
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
continue;
}
+ efi_map_region(md);
+
size = md->num_pages << EFI_PAGE_SHIFT;
end = md->phys_addr + size;
- start_pfn = PFN_DOWN(md->phys_addr);
- 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);
- continue;
- }
-
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;
}
+
new_memmap = krealloc(new_memmap,
(count + 1) * memmap.desc_size,
GFP_KERNEL);
+ if (!new_memmap)
+ goto err_out;
+
memcpy(new_memmap + (count * memmap.desc_size), md,
memmap.desc_size);
count++;
BUG_ON(!efi.systab);
+ efi_setup_page_tables();
+ efi_sync_low_kernel_mappings();
+
status = phys_efi_set_virtual_address_map(
memmap.desc_size * count,
memmap.desc_size,
efi.query_variable_info = virt_efi_query_variable_info;
efi.update_capsule = virt_efi_update_capsule;
efi.query_capsule_caps = virt_efi_query_capsule_caps;
- if (__supported_pte_mask & _PAGE_NX)
+
+ if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX))
runtime_code_page_mkexec();
kfree(new_memmap);
EFI_VARIABLE_BOOTSERVICE_ACCESS |
EFI_VARIABLE_RUNTIME_ACCESS,
0, NULL);
+
+ return;
+
+ err_out:
+ pr_err("Error reallocating memory, EFI runtime non-functional!\n");
}
/*
return EFI_SUCCESS;
}
EXPORT_SYMBOL_GPL(efi_query_variable_store);
+
+static int __init parse_efi_cmdline(char *str)
+{
+ if (*str == '=')
+ str++;
+
+ if (!strncmp(str, "old_map", 7))
+ set_bit(EFI_OLD_MEMMAP, &x86_efi_facility);
+
+ return 0;
+}
+early_param("efi", parse_efi_cmdline);
* claim EFI runtime service handler exclusively and to duplicate a memory in
* low memory space say 0 - 3G.
*/
-
static unsigned long efi_rt_eflags;
+void efi_sync_low_kernel_mappings(void) {}
+void efi_setup_page_tables(void) {}
+
+void __init efi_map_region(efi_memory_desc_t *md)
+{
+ old_map_region(md);
+}
+
void efi_call_phys_prelog(void)
{
struct desc_ptr gdt_descr;
#include <asm/efi.h>
#include <asm/cacheflush.h>
#include <asm/fixmap.h>
+#include <asm/realmode.h>
static pgd_t *save_pgd __initdata;
static unsigned long efi_flags __initdata;
+/*
+ * We allocate runtime services regions bottom-up, starting from -4G, i.e.
+ * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
+ */
+static u64 efi_va = -4 * (1UL << 30);
+#define EFI_VA_END (-68 * (1UL << 30))
+
+/*
+ * Scratch space used for switching the pagetable in the EFI stub
+ */
+struct efi_scratch {
+ u64 r15;
+ u64 prev_cr3;
+ pgd_t *efi_pgt;
+ bool use_pgd;
+};
+
static void __init early_code_mapping_set_exec(int executable)
{
efi_memory_desc_t *md;
int pgd;
int n_pgds;
+ if (!efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
early_code_mapping_set_exec(1);
local_irq_save(efi_flags);
*/
int pgd;
int n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE);
+
+ if (!efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
for (pgd = 0; pgd < n_pgds; pgd++)
set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), save_pgd[pgd]);
kfree(save_pgd);
early_code_mapping_set_exec(0);
}
+/*
+ * Add low kernel mappings for passing arguments to EFI functions.
+ */
+void efi_sync_low_kernel_mappings(void)
+{
+ unsigned num_pgds;
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return;
+
+ num_pgds = pgd_index(MODULES_END - 1) - pgd_index(PAGE_OFFSET);
+
+ memcpy(pgd + pgd_index(PAGE_OFFSET),
+ init_mm.pgd + pgd_index(PAGE_OFFSET),
+ sizeof(pgd_t) * num_pgds);
+}
+
+void efi_setup_page_tables(void)
+{
+ efi_scratch.efi_pgt = (pgd_t *)(unsigned long)real_mode_header->trampoline_pgd;
+
+ if (!efi_enabled(EFI_OLD_MEMMAP))
+ efi_scratch.use_pgd = true;
+}
+
+static void __init __map_region(efi_memory_desc_t *md, u64 va)
+{
+ pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd);
+ unsigned long pf = 0, size;
+ u64 end;
+
+ if (!(md->attribute & EFI_MEMORY_WB))
+ pf |= _PAGE_PCD;
+
+ size = md->num_pages << PAGE_SHIFT;
+ end = va + size;
+
+ if (kernel_map_pages_in_pgd(pgd, md->phys_addr, va, md->num_pages, pf))
+ pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
+ md->phys_addr, va);
+}
+
+void __init efi_map_region(efi_memory_desc_t *md)
+{
+ unsigned long size = md->num_pages << PAGE_SHIFT;
+ u64 pa = md->phys_addr;
+
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return old_map_region(md);
+
+ /*
+ * Make sure the 1:1 mappings are present as a catch-all for b0rked
+ * firmware which doesn't update all internal pointers after switching
+ * to virtual mode and would otherwise crap on us.
+ */
+ __map_region(md, md->phys_addr);
+
+ efi_va -= size;
+
+ /* Is PA 2M-aligned? */
+ if (!(pa & (PMD_SIZE - 1))) {
+ efi_va &= PMD_MASK;
+ } else {
+ u64 pa_offset = pa & (PMD_SIZE - 1);
+ u64 prev_va = efi_va;
+
+ /* get us the same offset within this 2M page */
+ efi_va = (efi_va & PMD_MASK) + pa_offset;
+
+ if (efi_va > prev_va)
+ efi_va -= PMD_SIZE;
+ }
+
+ if (efi_va < EFI_VA_END) {
+ pr_warn(FW_WARN "VA address range overflow!\n");
+ return;
+ }
+
+ /* Do the VA map */
+ __map_region(md, efi_va);
+ md->virt_addr = efi_va;
+}
+
void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
u32 type, u64 attribute)
{
mov %rsi, %cr0; \
mov (%rsp), %rsp
+ /* stolen from gcc */
+ .macro FLUSH_TLB_ALL
+ movq %r15, efi_scratch(%rip)
+ movq %r14, efi_scratch+8(%rip)
+ movq %cr4, %r15
+ movq %r15, %r14
+ andb $0x7f, %r14b
+ movq %r14, %cr4
+ movq %r15, %cr4
+ movq efi_scratch+8(%rip), %r14
+ movq efi_scratch(%rip), %r15
+ .endm
+
+ .macro SWITCH_PGT
+ cmpb $0, efi_scratch+24(%rip)
+ je 1f
+ movq %r15, efi_scratch(%rip) # r15
+ # save previous CR3
+ movq %cr3, %r15
+ movq %r15, efi_scratch+8(%rip) # prev_cr3
+ movq efi_scratch+16(%rip), %r15 # EFI pgt
+ movq %r15, %cr3
+ 1:
+ .endm
+
+ .macro RESTORE_PGT
+ cmpb $0, efi_scratch+24(%rip)
+ je 2f
+ movq efi_scratch+8(%rip), %r15
+ movq %r15, %cr3
+ movq efi_scratch(%rip), %r15
+ FLUSH_TLB_ALL
+ 2:
+ .endm
+
ENTRY(efi_call0)
SAVE_XMM
subq $32, %rsp
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $32, %rsp
RESTORE_XMM
ret
SAVE_XMM
subq $32, %rsp
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $32, %rsp
RESTORE_XMM
ret
SAVE_XMM
subq $32, %rsp
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $32, %rsp
RESTORE_XMM
ret
subq $32, %rsp
mov %rcx, %r8
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $32, %rsp
RESTORE_XMM
ret
mov %r8, %r9
mov %rcx, %r8
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $32, %rsp
RESTORE_XMM
ret
mov %r8, %r9
mov %rcx, %r8
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $48, %rsp
RESTORE_XMM
ret
mov %r8, %r9
mov %rcx, %r8
mov %rsi, %rcx
+ SWITCH_PGT
call *%rdi
+ RESTORE_PGT
addq $48, %rsp
RESTORE_XMM
ret
ENDPROC(efi_call6)
+
+ .data
+ENTRY(efi_scratch)
+ .fill 3,8,0
+ .byte 0
#define EFI_RUNTIME_SERVICES 3 /* Can we use runtime services? */
#define EFI_MEMMAP 4 /* Can we use EFI memory map? */
#define EFI_64BIT 5 /* Is the firmware 64-bit? */
+#define EFI_ARCH_1 6 /* First arch-specific bit */
#ifdef CONFIG_EFI
# ifdef CONFIG_X86
projects / ~andy / linux / commitdiff