diff options
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 158 |
1 files changed, 122 insertions, 36 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index e7bb483557c9..9121bc1b9453 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -25,12 +25,12 @@ #include <asm/cpufeature.h> #include <asm/pti.h> #include <asm/text-patching.h> +#include <asm/memtype.h> /* * We need to define the tracepoints somewhere, and tlb.c - * is only compied when SMP=y. + * is only compiled when SMP=y. */ -#define CREATE_TRACE_POINTS #include <trace/events/tlb.h> #include "mm_internal.h" @@ -49,7 +49,7 @@ * Index into __pte2cachemode_tbl[] are the caching attribute bits of the pte * (_PAGE_PWT, _PAGE_PCD, _PAGE_PAT) at index bit positions 0, 1, 2. */ -uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = { +static uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = { [_PAGE_CACHE_MODE_WB ] = 0 | 0 , [_PAGE_CACHE_MODE_WC ] = 0 | _PAGE_PCD, [_PAGE_CACHE_MODE_UC_MINUS] = 0 | _PAGE_PCD, @@ -57,9 +57,16 @@ uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = { [_PAGE_CACHE_MODE_WT ] = 0 | _PAGE_PCD, [_PAGE_CACHE_MODE_WP ] = 0 | _PAGE_PCD, }; -EXPORT_SYMBOL(__cachemode2pte_tbl); -uint8_t __pte2cachemode_tbl[8] = { +unsigned long cachemode2protval(enum page_cache_mode pcm) +{ + if (likely(pcm == 0)) + return 0; + return __cachemode2pte_tbl[pcm]; +} +EXPORT_SYMBOL(cachemode2protval); + +static uint8_t __pte2cachemode_tbl[8] = { [__pte2cm_idx( 0 | 0 | 0 )] = _PAGE_CACHE_MODE_WB, [__pte2cm_idx(_PAGE_PWT | 0 | 0 )] = _PAGE_CACHE_MODE_UC_MINUS, [__pte2cm_idx( 0 | _PAGE_PCD | 0 )] = _PAGE_CACHE_MODE_UC_MINUS, @@ -69,7 +76,32 @@ uint8_t __pte2cachemode_tbl[8] = { [__pte2cm_idx(0 | _PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC_MINUS, [__pte2cm_idx(_PAGE_PWT | _PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC, }; -EXPORT_SYMBOL(__pte2cachemode_tbl); + +/* + * Check that the write-protect PAT entry is set for write-protect. + * To do this without making assumptions how PAT has been set up (Xen has + * another layout than the kernel), translate the _PAGE_CACHE_MODE_WP cache + * mode via the __cachemode2pte_tbl[] into protection bits (those protection + * bits will select a cache mode of WP or better), and then translate the + * protection bits back into the cache mode using __pte2cm_idx() and the + * __pte2cachemode_tbl[] array. This will return the really used cache mode. + */ +bool x86_has_pat_wp(void) +{ + uint16_t prot = __cachemode2pte_tbl[_PAGE_CACHE_MODE_WP]; + + return __pte2cachemode_tbl[__pte2cm_idx(prot)] == _PAGE_CACHE_MODE_WP; +} + +enum page_cache_mode pgprot2cachemode(pgprot_t pgprot) +{ + unsigned long masked; + + masked = pgprot_val(pgprot) & _PAGE_CACHE_MASK; + if (likely(masked == 0)) + return 0; + return __pte2cachemode_tbl[__pte2cm_idx(masked)]; +} static unsigned long __initdata pgt_buf_start; static unsigned long __initdata pgt_buf_end; @@ -104,14 +136,12 @@ __ref void *alloc_low_pages(unsigned int num) unsigned long ret = 0; if (min_pfn_mapped < max_pfn_mapped) { - ret = memblock_find_in_range( + ret = memblock_phys_alloc_range( + PAGE_SIZE * num, PAGE_SIZE, min_pfn_mapped << PAGE_SHIFT, - max_pfn_mapped << PAGE_SHIFT, - PAGE_SIZE * num , PAGE_SIZE); + max_pfn_mapped << PAGE_SHIFT); } - if (ret) - memblock_reserve(ret, PAGE_SIZE * num); - else if (can_use_brk_pgt) + if (!ret && can_use_brk_pgt) ret = __pa(extend_brk(PAGE_SIZE * num, PAGE_SIZE)); if (!ret) @@ -121,8 +151,6 @@ __ref void *alloc_low_pages(unsigned int num) } else { pfn = pgt_buf_end; pgt_buf_end += num; - printk(KERN_DEBUG "BRK [%#010lx, %#010lx] PGTABLE\n", - pfn << PAGE_SHIFT, (pgt_buf_end << PAGE_SHIFT) - 1); } for (i = 0; i < num; i++) { @@ -136,16 +164,25 @@ __ref void *alloc_low_pages(unsigned int num) } /* - * By default need 3 4k for initial PMD_SIZE, 3 4k for 0-ISA_END_ADDRESS. - * With KASLR memory randomization, depending on the machine e820 memory - * and the PUD alignment. We may need twice more pages when KASLR memory + * By default need to be able to allocate page tables below PGD firstly for + * the 0-ISA_END_ADDRESS range and secondly for the initial PMD_SIZE mapping. + * With KASLR memory randomization, depending on the machine e820 memory and the + * PUD alignment, twice that many pages may be needed when KASLR memory * randomization is enabled. */ + +#ifndef CONFIG_X86_5LEVEL +#define INIT_PGD_PAGE_TABLES 3 +#else +#define INIT_PGD_PAGE_TABLES 4 +#endif + #ifndef CONFIG_RANDOMIZE_MEMORY -#define INIT_PGD_PAGE_COUNT 6 +#define INIT_PGD_PAGE_COUNT (2 * INIT_PGD_PAGE_TABLES) #else -#define INIT_PGD_PAGE_COUNT 12 +#define INIT_PGD_PAGE_COUNT (4 * INIT_PGD_PAGE_TABLES) #endif + #define INIT_PGT_BUF_SIZE (INIT_PGD_PAGE_COUNT * PAGE_SIZE) RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE); void __init early_alloc_pgt_buf(void) @@ -172,6 +209,19 @@ struct map_range { static int page_size_mask; +/* + * Save some of cr4 feature set we're using (e.g. Pentium 4MB + * enable and PPro Global page enable), so that any CPU's that boot + * up after us can get the correct flags. Invoked on the boot CPU. + */ +static inline void cr4_set_bits_and_update_boot(unsigned long mask) +{ + mmu_cr4_features |= mask; + if (trampoline_cr4_features) + *trampoline_cr4_features = mmu_cr4_features; + cr4_set_bits(mask); +} + static void __init probe_page_size_mask(void) { /* @@ -467,7 +517,7 @@ bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn) * the physical memory. To access them they are temporarily mapped. */ unsigned long __ref init_memory_mapping(unsigned long start, - unsigned long end) + unsigned long end, pgprot_t prot) { struct map_range mr[NR_RANGE_MR]; unsigned long ret = 0; @@ -481,7 +531,8 @@ unsigned long __ref init_memory_mapping(unsigned long start, for (i = 0; i < nr_range; i++) ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, - mr[i].page_size_mask); + mr[i].page_size_mask, + prot); add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT); @@ -521,7 +572,7 @@ static unsigned long __init init_range_memory_mapping( */ can_use_brk_pgt = max(start, (u64)pgt_buf_end<<PAGE_SHIFT) >= min(end, (u64)pgt_buf_top<<PAGE_SHIFT); - init_memory_mapping(start, end); + init_memory_mapping(start, end, PAGE_KERNEL); mapped_ram_size += end - start; can_use_brk_pgt = true; } @@ -561,20 +612,29 @@ static unsigned long __init get_new_step_size(unsigned long step_size) static void __init memory_map_top_down(unsigned long map_start, unsigned long map_end) { - unsigned long real_end, start, last_start; + unsigned long real_end, last_start; unsigned long step_size; unsigned long addr; unsigned long mapped_ram_size = 0; - /* xen has big range in reserved near end of ram, skip it at first.*/ - addr = memblock_find_in_range(map_start, map_end, PMD_SIZE, PMD_SIZE); + /* + * Systems that have many reserved areas near top of the memory, + * e.g. QEMU with less than 1G RAM and EFI enabled, or Xen, will + * require lots of 4K mappings which may exhaust pgt_buf. + * Start with top-most PMD_SIZE range aligned at PMD_SIZE to ensure + * there is enough mapped memory that can be allocated from + * memblock. + */ + addr = memblock_phys_alloc_range(PMD_SIZE, PMD_SIZE, map_start, + map_end); + memblock_phys_free(addr, PMD_SIZE); real_end = addr + PMD_SIZE; /* step_size need to be small so pgt_buf from BRK could cover it */ step_size = PMD_SIZE; max_pfn_mapped = 0; /* will get exact value next */ min_pfn_mapped = real_end >> PAGE_SHIFT; - last_start = start = real_end; + last_start = real_end; /* * We start from the top (end of memory) and go to the bottom. @@ -583,6 +643,8 @@ static void __init memory_map_top_down(unsigned long map_start, * for page table. */ while (last_start > map_start) { + unsigned long start; + if (last_start > step_size) { start = round_down(last_start - 1, step_size); if (start < map_start) @@ -646,6 +708,33 @@ static void __init memory_map_bottom_up(unsigned long map_start, } } +/* + * The real mode trampoline, which is required for bootstrapping CPUs + * occupies only a small area under the low 1MB. See reserve_real_mode() + * for details. + * + * If KASLR is disabled the first PGD entry of the direct mapping is copied + * to map the real mode trampoline. + * + * If KASLR is enabled, copy only the PUD which covers the low 1MB + * area. This limits the randomization granularity to 1GB for both 4-level + * and 5-level paging. + */ +static void __init init_trampoline(void) +{ +#ifdef CONFIG_X86_64 + /* + * The code below will alias kernel page-tables in the user-range of the + * address space, including the Global bit. So global TLB entries will + * be created when using the trampoline page-table. + */ + if (!kaslr_memory_enabled()) + trampoline_pgd_entry = init_top_pgt[pgd_index(__PAGE_OFFSET)]; + else + init_trampoline_kaslr(); +#endif +} + void __init init_mem_mapping(void) { unsigned long end; @@ -661,7 +750,7 @@ void __init init_mem_mapping(void) #endif /* the ISA range is always mapped regardless of memory holes */ - init_memory_mapping(0, ISA_END_ADDRESS); + init_memory_mapping(0, ISA_END_ADDRESS, PAGE_KERNEL); /* Init the trampoline, possibly with KASLR memory offset */ init_trampoline(); @@ -688,7 +777,7 @@ void __init init_mem_mapping(void) #ifdef CONFIG_X86_64 if (max_pfn > max_low_pfn) { - /* can we preseve max_low_pfn ?*/ + /* can we preserve max_low_pfn ?*/ max_low_pfn = max_pfn; } #else @@ -767,7 +856,7 @@ int devmem_is_allowed(unsigned long pagenr) /* * This must follow RAM test, since System RAM is considered a - * restricted resource under CONFIG_STRICT_IOMEM. + * restricted resource under CONFIG_STRICT_DEVMEM. */ if (iomem_is_exclusive(pagenr << PAGE_SHIFT)) { /* Low 1MB bypasses iomem restrictions. */ @@ -856,8 +945,6 @@ void free_kernel_image_pages(const char *what, void *begin, void *end) set_memory_np_noalias(begin_ul, len_pages); } -void __weak mem_encrypt_free_decrypted_mem(void) { } - void __ref free_initmem(void) { e820__reallocate_tables(); @@ -873,7 +960,7 @@ void __init free_initrd_mem(unsigned long start, unsigned long end) { /* * end could be not aligned, and We can not align that, - * decompresser could be confused by aligned initrd_end + * decompressor could be confused by aligned initrd_end * We already reserve the end partial page before in * - i386_start_kernel() * - x86_64_start_kernel() @@ -948,15 +1035,14 @@ void __init zone_sizes_init(void) max_zone_pfns[ZONE_HIGHMEM] = max_pfn; #endif - free_area_init_nodes(max_zone_pfns); + free_area_init(max_zone_pfns); } -__visible DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = { +__visible DEFINE_PER_CPU_ALIGNED(struct tlb_state, cpu_tlbstate) = { .loaded_mm = &init_mm, .next_asid = 1, .cr4 = ~0UL, /* fail hard if we screw up cr4 shadow initialization */ }; -EXPORT_PER_CPU_SYMBOL(cpu_tlbstate); void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache) { @@ -968,7 +1054,7 @@ void update_cache_mode_entry(unsigned entry, enum page_cache_mode cache) } #ifdef CONFIG_SWAP -unsigned long max_swapfile_size(void) +unsigned long arch_max_swapfile_size(void) { unsigned long pages; |