From: Yinghai Lu Date: Tue, 24 Jun 2008 19:18:14 +0000 (-0700) Subject: x86: introduce init_memory_mapping for 32bit #1 X-Git-Tag: v2.6.27-rc1~1106^2~175 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4e29684c40f2a332ba4d05f6482d5807725d5624;p=linux-2.6 x86: introduce init_memory_mapping for 32bit #1 ... so can we use mem below max_low_pfn earlier. this allows us to move several functions more early instead of waiting to after paging_init. That includes moving relocate_initrd() earlier in the bootup, and kva related early setup done in initmem_init. (in followup patches) Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/kernel/setup_32.c b/arch/x86/kernel/setup_32.c index bba8d57bd7..03007cada0 100644 --- a/arch/x86/kernel/setup_32.c +++ b/arch/x86/kernel/setup_32.c @@ -226,10 +226,8 @@ static void __init reserve_initrd(void) } /* We need to move the initrd down into lowmem */ - ramdisk_target = max_pfn_mapped<>1), - end_of_lowmem, ramdisk_size, - PAGE_SIZE); + ramdisk_here = find_e820_area(0, end_of_lowmem, ramdisk_size, + PAGE_SIZE); if (ramdisk_here == -1ULL) panic("Cannot find place for new RAMDISK of size %lld\n", @@ -433,8 +431,12 @@ void __init setup_arch(char **cmdline_p) max_pfn = e820_end_of_ram(); } + /* max_low_pfn get updated here */ find_low_pfn_range(); + /* max_pfn_mapped is updated here */ + init_memory_mapping(0, (max_low_pfn << PAGE_SHIFT)); + reserve_initrd(); dmi_scan_machine(); diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 20ca29591a..619058e6bf 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -57,6 +57,27 @@ unsigned long highstart_pfn, highend_pfn; static noinline int do_test_wp_bit(void); + +static unsigned long __initdata table_start; +static unsigned long __meminitdata table_end; +static unsigned long __meminitdata table_top; + +static int __initdata after_init_bootmem; + +static __init void *alloc_low_page(unsigned long *phys) +{ + unsigned long pfn = table_end++; + void *adr; + + if (pfn >= table_top) + panic("alloc_low_page: ran out of memory"); + + adr = __va(pfn * PAGE_SIZE); + memset(adr, 0, PAGE_SIZE); + *phys = pfn * PAGE_SIZE; + return adr; +} + /* * Creates a middle page table and puts a pointer to it in the * given global directory entry. This only returns the gd entry @@ -68,9 +89,12 @@ static pmd_t * __init one_md_table_init(pgd_t *pgd) pmd_t *pmd_table; #ifdef CONFIG_X86_PAE + unsigned long phys; if (!(pgd_val(*pgd) & _PAGE_PRESENT)) { - pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE); - + if (after_init_bootmem) + pmd_table = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE); + else + pmd_table = (pmd_t *)alloc_low_page(&phys); paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT); set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT)); pud = pud_offset(pgd, 0); @@ -92,12 +116,16 @@ static pte_t * __init one_page_table_init(pmd_t *pmd) if (!(pmd_val(*pmd) & _PAGE_PRESENT)) { pte_t *page_table = NULL; + if (after_init_bootmem) { #ifdef CONFIG_DEBUG_PAGEALLOC - page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE); + page_table = (pte_t *) alloc_bootmem_pages(PAGE_SIZE); #endif - if (!page_table) { - page_table = + if (!page_table) + page_table = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE); + } else { + unsigned long phys; + page_table = (pte_t *)alloc_low_page(&phys); } paravirt_alloc_pte(&init_mm, __pa(page_table) >> PAGE_SHIFT); @@ -155,7 +183,9 @@ static inline int is_kernel_text(unsigned long addr) * of max_low_pfn pages, by creating page tables starting from address * PAGE_OFFSET: */ -static void __init kernel_physical_mapping_init(pgd_t *pgd_base) +static void __init kernel_physical_mapping_init(pgd_t *pgd_base, + unsigned long start, + unsigned long end) { int pgd_idx, pmd_idx, pte_ofs; unsigned long pfn; @@ -163,18 +193,19 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base) pmd_t *pmd; pte_t *pte; unsigned pages_2m = 0, pages_4k = 0; + unsigned limit_pfn = end >> PAGE_SHIFT; pgd_idx = pgd_index(PAGE_OFFSET); pgd = pgd_base + pgd_idx; - pfn = 0; + pfn = start >> PAGE_SHIFT; for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) { pmd = one_md_table_init(pgd); - if (pfn >= max_low_pfn) + if (pfn >= limit_pfn) continue; for (pmd_idx = 0; - pmd_idx < PTRS_PER_PMD && pfn < max_low_pfn; + pmd_idx < PTRS_PER_PMD && pfn < limit_pfn; pmd++, pmd_idx++) { unsigned int addr = pfn * PAGE_SIZE + PAGE_OFFSET; @@ -418,20 +449,7 @@ static void __init pagetable_init(void) paravirt_pagetable_setup_start(pgd_base); - /* Enable PSE if available */ - if (cpu_has_pse) - set_in_cr4(X86_CR4_PSE); - - /* Enable PGE if available */ - if (cpu_has_pge) { - set_in_cr4(X86_CR4_PGE); - __PAGE_KERNEL |= _PAGE_GLOBAL; - __PAGE_KERNEL_EXEC |= _PAGE_GLOBAL; - } - - kernel_physical_mapping_init(pgd_base); remap_numa_kva(); - /* * Fixed mappings, only the page table structure has to be * created - mappings will be set by set_fixmap(): @@ -703,6 +721,7 @@ void __init setup_bootmem_allocator(void) free_bootmem_with_active_regions(i, max_low_pfn); early_res_to_bootmem(0, max_low_pfn<> PUD_SHIFT; + tables = PAGE_ALIGN(puds * sizeof(pud_t)); + + pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; + tables += PAGE_ALIGN(pmds * sizeof(pmd_t)); + + /* + * RED-PEN putting page tables only on node 0 could + * cause a hotspot and fill up ZONE_DMA. The page tables + * need roughly 0.5KB per GB. + */ + start = 0x7000; + table_start = find_e820_area(start, max_pfn_mapped<>= PAGE_SHIFT; + table_end = table_start; + table_top = table_start + (tables>>PAGE_SHIFT); + + printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", + end, table_start << PAGE_SHIFT, + (table_start << PAGE_SHIFT) + tables); +} + +unsigned long __init_refok init_memory_mapping(unsigned long start, + unsigned long end) +{ + pgd_t *pgd_base = swapper_pg_dir; + + /* + * Find space for the kernel direct mapping tables. + */ + if (!after_init_bootmem) + find_early_table_space(end); + +#ifdef CONFIG_X86_PAE + set_nx(); + if (nx_enabled) + printk(KERN_INFO "NX (Execute Disable) protection: active\n"); +#endif + + /* Enable PSE if available */ + if (cpu_has_pse) + set_in_cr4(X86_CR4_PSE); + + /* Enable PGE if available */ + if (cpu_has_pge) { + set_in_cr4(X86_CR4_PGE); + __PAGE_KERNEL |= _PAGE_GLOBAL; + __PAGE_KERNEL_EXEC |= _PAGE_GLOBAL; + } + + kernel_physical_mapping_init(pgd_base, start, end); + + load_cr3(swapper_pg_dir); + + __flush_tlb_all(); + + if (!after_init_bootmem) + reserve_early(table_start << PAGE_SHIFT, + table_end << PAGE_SHIFT, "PGTABLE"); + + return end >> PAGE_SHIFT; +} + /* * paging_init() sets up the page tables - note that the first 8MB are * already mapped by head.S. @@ -732,15 +822,8 @@ static void __init remapped_pgdat_init(void) */ void __init paging_init(void) { -#ifdef CONFIG_X86_PAE - set_nx(); - if (nx_enabled) - printk(KERN_INFO "NX (Execute Disable) protection: active\n"); -#endif pagetable_init(); - load_cr3(swapper_pg_dir); - __flush_tlb_all(); kmap_init(); diff --git a/include/asm-x86/page_32.h b/include/asm-x86/page_32.h index 3810d14051..4ae1daba12 100644 --- a/include/asm-x86/page_32.h +++ b/include/asm-x86/page_32.h @@ -93,6 +93,8 @@ extern int sysctl_legacy_va_layout; #define MAXMEM (-__PAGE_OFFSET - __VMALLOC_RESERVE) extern void find_low_pfn_range(void); +extern unsigned long init_memory_mapping(unsigned long start, + unsigned long end); extern void initmem_init(unsigned long, unsigned long); extern void zone_sizes_init(void); extern void setup_bootmem_allocator(void);