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Diffstat (limited to 'arch/x86/mm/init_32.c')
-rw-r--r--arch/x86/mm/init_32.c90
1 files changed, 79 insertions, 11 deletions
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 60ec1d08ff24..8396868e82c5 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -31,6 +31,7 @@
#include <linux/cpumask.h>
#include <asm/asm.h>
+#include <asm/bios_ebda.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/uaccess.h>
@@ -47,6 +48,7 @@
#include <asm/paravirt.h>
#include <asm/setup.h>
#include <asm/cacheflush.h>
+#include <asm/smp.h>
unsigned int __VMALLOC_RESERVE = 128 << 20;
@@ -194,11 +196,30 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
- unsigned pages_2m = 0, pages_4k = 0;
+ unsigned pages_2m, pages_4k;
+ int mapping_iter;
+
+ /*
+ * First iteration will setup identity mapping using large/small pages
+ * based on use_pse, with other attributes same as set by
+ * the early code in head_32.S
+ *
+ * Second iteration will setup the appropriate attributes (NX, GLOBAL..)
+ * as desired for the kernel identity mapping.
+ *
+ * This two pass mechanism conforms to the TLB app note which says:
+ *
+ * "Software should not write to a paging-structure entry in a way
+ * that would change, for any linear address, both the page size
+ * and either the page frame or attributes."
+ */
+ mapping_iter = 1;
if (!cpu_has_pse)
use_pse = 0;
+repeat:
+ pages_2m = pages_4k = 0;
pfn = start_pfn;
pgd_idx = pgd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
pgd = pgd_base + pgd_idx;
@@ -224,6 +245,13 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
if (use_pse) {
unsigned int addr2;
pgprot_t prot = PAGE_KERNEL_LARGE;
+ /*
+ * first pass will use the same initial
+ * identity mapping attribute + _PAGE_PSE.
+ */
+ pgprot_t init_prot =
+ __pgprot(PTE_IDENT_ATTR |
+ _PAGE_PSE);
addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
PAGE_OFFSET + PAGE_SIZE-1;
@@ -233,7 +261,10 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
prot = PAGE_KERNEL_LARGE_EXEC;
pages_2m++;
- set_pmd(pmd, pfn_pmd(pfn, prot));
+ if (mapping_iter == 1)
+ set_pmd(pmd, pfn_pmd(pfn, init_prot));
+ else
+ set_pmd(pmd, pfn_pmd(pfn, prot));
pfn += PTRS_PER_PTE;
continue;
@@ -245,17 +276,43 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
for (; pte_ofs < PTRS_PER_PTE && pfn < end_pfn;
pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
pgprot_t prot = PAGE_KERNEL;
+ /*
+ * first pass will use the same initial
+ * identity mapping attribute.
+ */
+ pgprot_t init_prot = __pgprot(PTE_IDENT_ATTR);
if (is_kernel_text(addr))
prot = PAGE_KERNEL_EXEC;
pages_4k++;
- set_pte(pte, pfn_pte(pfn, prot));
+ if (mapping_iter == 1)
+ set_pte(pte, pfn_pte(pfn, init_prot));
+ else
+ set_pte(pte, pfn_pte(pfn, prot));
}
}
}
- update_page_count(PG_LEVEL_2M, pages_2m);
- update_page_count(PG_LEVEL_4K, pages_4k);
+ if (mapping_iter == 1) {
+ /*
+ * update direct mapping page count only in the first
+ * iteration.
+ */
+ update_page_count(PG_LEVEL_2M, pages_2m);
+ update_page_count(PG_LEVEL_4K, pages_4k);
+
+ /*
+ * local global flush tlb, which will flush the previous
+ * mappings present in both small and large page TLB's.
+ */
+ __flush_tlb_all();
+
+ /*
+ * Second iteration will set the actual desired PTE attributes.
+ */
+ mapping_iter = 2;
+ goto repeat;
+ }
}
/*
@@ -501,7 +558,7 @@ void zap_low_mappings(void)
int nx_enabled;
-pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL);
+pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
EXPORT_SYMBOL_GPL(__supported_pte_mask);
#ifdef CONFIG_X86_PAE
@@ -718,7 +775,7 @@ void __init setup_bootmem_allocator(void)
after_init_bootmem = 1;
}
-static void __init find_early_table_space(unsigned long end)
+static void __init find_early_table_space(unsigned long end, int use_pse)
{
unsigned long puds, pmds, ptes, tables, start;
@@ -728,7 +785,7 @@ static void __init find_early_table_space(unsigned long end)
pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
tables += PAGE_ALIGN(pmds * sizeof(pmd_t));
- if (cpu_has_pse) {
+ if (use_pse) {
unsigned long extra;
extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
@@ -768,12 +825,22 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
pgd_t *pgd_base = swapper_pg_dir;
unsigned long start_pfn, end_pfn;
unsigned long big_page_start;
+#ifdef CONFIG_DEBUG_PAGEALLOC
+ /*
+ * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+ * This will simplify cpa(), which otherwise needs to support splitting
+ * large pages into small in interrupt context, etc.
+ */
+ int use_pse = 0;
+#else
+ int use_pse = cpu_has_pse;
+#endif
/*
* Find space for the kernel direct mapping tables.
*/
if (!after_init_bootmem)
- find_early_table_space(end);
+ find_early_table_space(end, use_pse);
#ifdef CONFIG_X86_PAE
set_nx();
@@ -819,7 +886,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
if (start_pfn < end_pfn)
kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn,
- cpu_has_pse);
+ use_pse);
/* tail is not big page alignment ? */
start_pfn = end_pfn;
@@ -903,6 +970,8 @@ void __init mem_init(void)
int codesize, reservedpages, datasize, initsize;
int tmp;
+ start_periodic_check_for_corruption();
+
#ifdef CONFIG_FLATMEM
BUG_ON(!mem_map);
#endif
@@ -982,7 +1051,6 @@ void __init mem_init(void)
if (boot_cpu_data.wp_works_ok < 0)
test_wp_bit();
- cpa_init();
save_pg_dir();
zap_low_mappings();
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-17 11:57:32 +0300