diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 6 | ||||
| -rw-r--r-- | Documentation/x86/x86_64/mm.txt | 7 | ||||
| -rw-r--r-- | arch/x86/include/asm/efi.h | 64 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable_types.h | 3 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr.c | 461 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi.c | 111 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi_32.c | 9 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 109 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi_stub_64.S | 54 | ||||
| -rw-r--r-- | include/linux/efi.h | 1 |
10 files changed, 755 insertions, 70 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 50680a59a2f..e06e99303dd 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -890,6 +890,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. 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 diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index 881582f75c9..c584a51add1 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -28,4 +28,11 @@ reference. 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 diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index 65c6e6e3a55..89a05b0507b 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -1,6 +1,24 @@ #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" @@ -69,24 +87,31 @@ extern u64 efi_call6(void *fp, u64 arg1, u64 arg2, u64 arg3, 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); @@ -95,12 +120,17 @@ extern void __iomem *efi_ioremap(unsigned long addr, unsigned long size, 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 diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 0ecac257fb2..a83aa44bb1f 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -382,7 +382,8 @@ static inline void update_page_count(int level, unsigned long pages) { } */ 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 */ diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index bb32480c2d7..b3b19f46c01 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -30,6 +30,7 @@ */ struct cpa_data { unsigned long *vaddr; + pgd_t *pgd; pgprot_t mask_set; pgprot_t mask_clr; int numpages; @@ -322,17 +323,9 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address, 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; @@ -361,8 +354,31 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) 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() @@ -437,7 +453,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, * 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; @@ -543,7 +559,8 @@ 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; @@ -556,7 +573,7 @@ __split_large_page(pte_t *kpte, unsigned long address, struct page *base) * 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; @@ -632,7 +649,8 @@ __split_large_page(pte_t *kpte, unsigned long address, struct page *base) 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; @@ -644,15 +662,390 @@ static int split_large_page(pte_t *kpte, unsigned long address) 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. */ @@ -697,7 +1090,7 @@ static int __change_page_attr(struct cpa_data *cpa, int primary) 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); @@ -761,7 +1154,7 @@ repeat: /* * 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 @@ -910,6 +1303,8 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages, int ret, cache, checkalias; unsigned long baddr = 0; + memset(&cpa, 0, sizeof(cpa)); + /* * Check, if we are requested to change a not supported * feature: @@ -1356,6 +1751,7 @@ static int __set_pages_p(struct page *page, int numpages) { 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), @@ -1374,6 +1770,7 @@ static int __set_pages_np(struct page *page, int numpages) { 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), @@ -1434,6 +1831,36 @@ bool kernel_page_present(struct page *page) #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. diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 92c02344a06..f8ec4dafc74 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -12,6 +12,8 @@ * 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 @@ -51,7 +53,7 @@ #include <asm/x86_init.h> #include <asm/rtc.h> -#define EFI_DEBUG 1 +#define EFI_DEBUG #define EFI_MIN_RESERVE 5120 @@ -398,9 +400,9 @@ int __init efi_memblock_x86_reserve_range(void) return 0; } -#if EFI_DEBUG static void __init print_efi_memmap(void) { +#ifdef EFI_DEBUG efi_memory_desc_t *md; void *p; int i; @@ -415,8 +417,8 @@ static void __init print_efi_memmap(void) 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) { @@ -696,10 +698,7 @@ void __init efi_init(void) x86_platform.set_wallclock = efi_set_rtc_mmss; } #endif - -#if EFI_DEBUG print_efi_memmap(); -#endif } void __init efi_late_init(void) @@ -748,21 +747,56 @@ void efi_memory_uc(u64 addr, unsigned long size) 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; @@ -771,7 +805,6 @@ void __init efi_enter_virtual_mode(void) * 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; @@ -802,6 +835,7 @@ void __init efi_enter_virtual_mode(void) continue; } prev_md = md; + } for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) { @@ -814,36 +848,24 @@ void __init efi_enter_virtual_mode(void) 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++; @@ -851,6 +873,9 @@ void __init efi_enter_virtual_mode(void) 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, @@ -883,7 +908,8 @@ void __init efi_enter_virtual_mode(void) 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); @@ -894,6 +920,11 @@ void __init efi_enter_virtual_mode(void) EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL); + + return; + + err_out: + pr_err("Error reallocating memory, EFI runtime non-functional!\n"); } /* @@ -1013,3 +1044,15 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) 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); diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index 40e446941dd..e94557cf548 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -37,9 +37,16 @@ * 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; diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 39a0e7f1f0a..bf286c386d3 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -38,10 +38,28 @@ #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; @@ -65,6 +83,9 @@ void __init efi_call_phys_prelog(void) int pgd; int n_pgds; + if (!efi_enabled(EFI_OLD_MEMMAP)) + return; + early_code_mapping_set_exec(1); local_irq_save(efi_flags); @@ -86,6 +107,10 @@ void __init efi_call_phys_epilog(void) */ 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); @@ -94,6 +119,90 @@ void __init efi_call_phys_epilog(void) 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) { diff --git a/arch/x86/platform/efi/efi_stub_64.S b/arch/x86/platform/efi/efi_stub_64.S index 4c07ccab814..88073b14029 100644 --- a/arch/x86/platform/efi/efi_stub_64.S +++ b/arch/x86/platform/efi/efi_stub_64.S @@ -34,10 +34,47 @@ 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 @@ -47,7 +84,9 @@ ENTRY(efi_call1) SAVE_XMM subq $32, %rsp mov %rsi, %rcx + SWITCH_PGT call *%rdi + RESTORE_PGT addq $32, %rsp RESTORE_XMM ret @@ -57,7 +96,9 @@ ENTRY(efi_call2) SAVE_XMM subq $32, %rsp mov %rsi, %rcx + SWITCH_PGT call *%rdi + RESTORE_PGT addq $32, %rsp RESTORE_XMM ret @@ -68,7 +109,9 @@ ENTRY(efi_call3) subq $32, %rsp mov %rcx, %r8 mov %rsi, %rcx + SWITCH_PGT call *%rdi + RESTORE_PGT addq $32, %rsp RESTORE_XMM ret @@ -80,7 +123,9 @@ ENTRY(efi_call4) mov %r8, %r9 mov %rcx, %r8 mov %rsi, %rcx + SWITCH_PGT call *%rdi + RESTORE_PGT addq $32, %rsp RESTORE_XMM ret @@ -93,7 +138,9 @@ ENTRY(efi_call5) mov %r8, %r9 mov %rcx, %r8 mov %rsi, %rcx + SWITCH_PGT call *%rdi + RESTORE_PGT addq $48, %rsp RESTORE_XMM ret @@ -109,8 +156,15 @@ ENTRY(efi_call6) 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 diff --git a/include/linux/efi.h b/include/linux/efi.h index bc5687d0f31..6c0ca528300 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -653,6 +653,7 @@ extern int __init efi_setup_pcdp_console(char *); #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 |