From ec315732f2856ee6bdea67922fec1c1acb41eb16 Mon Sep 17 00:00:00 2001 From: Pekka Enberg Date: Thu, 5 Mar 2009 10:29:50 +0200 Subject: [PATCH 02/17] x86: add gbpages support to 32-bit init_memory_mapping() Impact: cleanup To reduce the diff between the 32-bit and 64-bit versions of init_memory_mapping(), add gbpages support to the 32-bit version. Cc: Yinghai Lu Signed-off-by: Pekka Enberg --- arch/x86/mm/init_32.c | 23 ++++++++++++++++++----- 1 files changed, 18 insertions(+), 5 deletions(-) diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index ad4e03c..5fad0f9 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -65,6 +65,8 @@ static unsigned long __meminitdata table_top; static int __initdata after_init_bootmem; +int direct_gbpages; + static __init void *alloc_low_page(void) { unsigned long pfn = table_end++; @@ -831,14 +833,22 @@ void __init setup_bootmem_allocator(void) after_init_bootmem = 1; } -static void __init find_early_table_space(unsigned long end, int use_pse) +static void __init find_early_table_space(unsigned long end, int use_pse, + int use_gbpages) { unsigned long puds, pmds, ptes, tables, start; puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); - pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; + if (use_gbpages) { + unsigned long extra; + + extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); + pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; + } else + pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; + tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); if (use_pse) { @@ -913,7 +923,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, struct map_range mr[NR_RANGE_MR]; int nr_range, i; - int use_pse; + int use_pse, use_gbpages; printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end); @@ -923,9 +933,10 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, * This will simplify cpa(), which otherwise needs to support splitting * large pages into small in interrupt context, etc. */ - use_pse = 0; + use_pse = use_gbpages = 0; #else use_pse = cpu_has_pse; + use_gbpages = direct_gbpages; #endif #ifdef CONFIG_X86_PAE @@ -944,6 +955,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, __supported_pte_mask |= _PAGE_GLOBAL; } + if (use_gbpages) + page_size_mask |= 1 << PG_LEVEL_1G; if (use_pse) page_size_mask |= 1 << PG_LEVEL_2M; @@ -1015,7 +1028,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, * nodes are discovered. */ if (!after_init_bootmem) - find_early_table_space(end, use_pse); + find_early_table_space(end, use_pse, use_gbpages); for (i = 0; i < nr_range; i++) kernel_physical_mapping_init(pgd_base, -- 1.5.4.3