X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fmm%2Finit_32.c;h=ec30d10154b657a63ab07b5e25b4298c10f4aabe;hb=42a886af728c089df8da1b0017b0e7e6c81b5335;hp=8106bba41ecb4b7ce5b87a58545c50102cc562b7;hpb=76ebd0548df6ee48586e9b80d8fc2f58aa5fb51c;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 8106bba..ec30d10 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -1,5 +1,4 @@ /* - * linux/arch/i386/mm/init.c * * Copyright (C) 1995 Linus Torvalds * @@ -47,9 +46,12 @@ #include #include #include +#include unsigned int __VMALLOC_RESERVE = 128 << 20; +unsigned long max_pfn_mapped; + DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); unsigned long highstart_pfn, highend_pfn; @@ -69,7 +71,7 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd) if (!(pgd_val(*pgd) & _PAGE_PRESENT)) { pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE); - paravirt_alloc_pd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT); + paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT); set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT)); pud = pud_offset(pgd, 0); BUG_ON(pmd_table != pmd_offset(pud, 0)); @@ -98,7 +100,7 @@ static pte_t * __init one_page_table_init(pmd_t *pmd) (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE); } - paravirt_alloc_pt(&init_mm, __pa(page_table) >> PAGE_SHIFT); + paravirt_alloc_pte(&init_mm, __pa(page_table) >> PAGE_SHIFT); set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE)); BUG_ON(page_table != pte_offset_kernel(pmd, 0)); } @@ -178,8 +180,13 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) /* * Map with big pages if possible, otherwise * create normal page tables: + * + * Don't use a large page for the first 2/4MB of memory + * because there are often fixed size MTRRs in there + * and overlapping MTRRs into large pages can cause + * slowdowns. */ - if (cpu_has_pse) { + if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0)) { unsigned int addr2; pgprot_t prot = PAGE_KERNEL_LARGE; @@ -193,6 +200,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) set_pmd(pmd, pfn_pmd(pfn, prot)); pfn += PTRS_PER_PTE; + max_pfn_mapped = pfn; continue; } pte = one_page_table_init(pmd); @@ -207,6 +215,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) set_pte(pte, pfn_pte(pfn, prot)); } + max_pfn_mapped = pfn; } } } @@ -218,6 +227,25 @@ static inline int page_kills_ppro(unsigned long pagenr) return 0; } +/* + * devmem_is_allowed() checks to see if /dev/mem access to a certain address + * is valid. The argument is a physical page number. + * + * + * On x86, access has to be given to the first megabyte of ram because that area + * contains bios code and data regions used by X and dosemu and similar apps. + * Access has to be given to non-kernel-ram areas as well, these contain the PCI + * mmio resources as well as potential bios/acpi data regions. + */ +int devmem_is_allowed(unsigned long pagenr) +{ + if (pagenr <= 256) + return 1; + if (!page_is_ram(pagenr)) + return 1; + return 0; +} + #ifdef CONFIG_HIGHMEM pte_t *kmap_pte; pgprot_t kmap_prot; @@ -259,47 +287,17 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base) pkmap_page_table = pte; } -static void __meminit free_new_highpage(struct page *page) -{ - init_page_count(page); - __free_page(page); - totalhigh_pages++; -} - void __init add_one_highpage_init(struct page *page, int pfn, int bad_ppro) { if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) { ClearPageReserved(page); - free_new_highpage(page); + init_page_count(page); + __free_page(page); + totalhigh_pages++; } else SetPageReserved(page); } -static int __meminit -add_one_highpage_hotplug(struct page *page, unsigned long pfn) -{ - free_new_highpage(page); - totalram_pages++; -#ifdef CONFIG_FLATMEM - max_mapnr = max(pfn, max_mapnr); -#endif - num_physpages++; - - return 0; -} - -/* - * Not currently handling the NUMA case. - * Assuming single node and all memory that - * has been added dynamically that would be - * onlined here is in HIGHMEM. - */ -void __meminit online_page(struct page *page) -{ - ClearPageReserved(page); - add_one_highpage_hotplug(page, page_to_pfn(page)); -} - #ifndef CONFIG_NUMA static void __init set_highmem_pages_init(int bad_ppro) { @@ -356,7 +354,7 @@ void __init native_pagetable_setup_start(pgd_t *base) pte_clear(NULL, va, pte); } - paravirt_alloc_pd(&init_mm, __pa(base) >> PAGE_SHIFT); + paravirt_alloc_pmd(&init_mm, __pa(base) >> PAGE_SHIFT); } void __init native_pagetable_setup_done(pgd_t *base) @@ -440,15 +438,13 @@ void zap_low_mappings(void) { int i; - save_pg_dir(); - /* * Zap initial low-memory mappings. * * Note that "pgd_clear()" doesn't do it for * us, because pgd_clear() is a no-op on i386. */ - for (i = 0; i < USER_PTRS_PER_PGD; i++) { + for (i = 0; i < KERNEL_PGD_BOUNDARY; i++) { #ifdef CONFIG_X86_PAE set_pgd(swapper_pg_dir+i, __pgd(1 + __pa(empty_zero_page))); #else @@ -538,9 +534,9 @@ void __init paging_init(void) /* * Test if the WP bit works in supervisor mode. It isn't supported on 386's - * and also on some strange 486's (NexGen etc.). All 586+'s are OK. This - * used to involve black magic jumps to work around some nasty CPU bugs, - * but fortunately the switch to using exceptions got rid of all that. + * and also on some strange 486's. All 586+'s are OK. This used to involve + * black magic jumps to work around some nasty CPU bugs, but fortunately the + * switch to using exceptions got rid of all that. */ static void __init test_wp_bit(void) { @@ -665,16 +661,8 @@ void __init mem_init(void) test_wp_bit(); cpa_init(); - - /* - * Subtle. SMP is doing it's boot stuff late (because it has to - * fork idle threads) - but it also needs low mappings for the - * protected-mode entry to work. We zap these entries only after - * the WP-bit has been tested. - */ -#ifndef CONFIG_SMP + save_pg_dir(); zap_low_mappings(); -#endif } #ifdef CONFIG_MEMORY_HOTPLUG @@ -722,25 +710,17 @@ void mark_rodata_ro(void) unsigned long start = PFN_ALIGN(_text); unsigned long size = PFN_ALIGN(_etext) - start; -#ifndef CONFIG_KPROBES -#ifdef CONFIG_HOTPLUG_CPU - /* It must still be possible to apply SMP alternatives. */ - if (num_possible_cpus() <= 1) -#endif - { - set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); - printk(KERN_INFO "Write protecting the kernel text: %luk\n", - size >> 10); + set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT); + printk(KERN_INFO "Write protecting the kernel text: %luk\n", + size >> 10); #ifdef CONFIG_CPA_DEBUG - printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n", - start, start+size); - set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT); + printk(KERN_INFO "Testing CPA: Reverting %lx-%lx\n", + start, start+size); + set_pages_rw(virt_to_page(start), size>>PAGE_SHIFT); - printk(KERN_INFO "Testing CPA: write protecting again\n"); - set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT); -#endif - } + printk(KERN_INFO "Testing CPA: write protecting again\n"); + set_pages_ro(virt_to_page(start), size>>PAGE_SHIFT); #endif start += size; size = (unsigned long)__end_rodata - start;