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-rw-r--r--arch/x86/mm/init.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index cc7fe660f33d..3a21b136da24 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -2,10 +2,338 @@
#include <linux/swap.h>
#include <asm/cacheflush.h>
+#include <asm/e820.h>
#include <asm/page.h>
#include <asm/page_types.h>
#include <asm/sections.h>
#include <asm/system.h>
+#include <asm/tlbflush.h>
+
+#ifdef CONFIG_X86_32
+extern void __init early_ioremap_page_table_range_init(void);
+extern void __init kernel_physical_mapping_init(unsigned long start_pfn,
+ unsigned long end_pfn,
+ int use_pse);
+#endif
+
+#ifdef CONFIG_X86_64
+extern unsigned long __meminit
+kernel_physical_mapping_init(unsigned long start,
+ unsigned long end,
+ unsigned long page_size_mask);
+#endif
+
+unsigned long __initdata table_start;
+unsigned long __meminitdata table_end;
+unsigned long __meminitdata table_top;
+
+int after_bootmem;
+
+int direct_gbpages
+#ifdef CONFIG_DIRECT_GBPAGES
+ = 1
+#endif
+;
+
+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);
+
+ 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) {
+ unsigned long extra;
+
+ extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
+#ifdef CONFIG_X86_32
+ extra += PMD_SIZE;
+#endif
+ ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ } else
+ ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+ tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
+
+#ifdef CONFIG_X86_32
+ /* for fixmap */
+ tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
+#endif
+
+ /*
+ * 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.
+ */
+#ifdef CONFIG_X86_32
+ start = 0x7000;
+ table_start = find_e820_area(start, max_pfn_mapped<<PAGE_SHIFT,
+ tables, PAGE_SIZE);
+#else /* CONFIG_X86_64 */
+ start = 0x8000;
+ table_start = find_e820_area(start, end, tables, PAGE_SIZE);
+#endif
+ if (table_start == -1UL)
+ panic("Cannot find space for the kernel page tables");
+
+ table_start >>= 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_top << PAGE_SHIFT);
+}
+
+struct map_range {
+ unsigned long start;
+ unsigned long end;
+ unsigned page_size_mask;
+};
+
+#ifdef CONFIG_X86_32
+#define NR_RANGE_MR 3
+#else /* CONFIG_X86_64 */
+#define NR_RANGE_MR 5
+#endif
+
+static int save_mr(struct map_range *mr, int nr_range,
+ unsigned long start_pfn, unsigned long end_pfn,
+ unsigned long page_size_mask)
+{
+ if (start_pfn < end_pfn) {
+ if (nr_range >= NR_RANGE_MR)
+ panic("run out of range for init_memory_mapping\n");
+ mr[nr_range].start = start_pfn<<PAGE_SHIFT;
+ mr[nr_range].end = end_pfn<<PAGE_SHIFT;
+ mr[nr_range].page_size_mask = page_size_mask;
+ nr_range++;
+ }
+
+ return nr_range;
+}
+
+#ifdef CONFIG_X86_64
+static void __init init_gbpages(void)
+{
+ if (direct_gbpages && cpu_has_gbpages)
+ printk(KERN_INFO "Using GB pages for direct mapping\n");
+ else
+ direct_gbpages = 0;
+}
+#else
+static inline void init_gbpages(void)
+{
+}
+#endif
+
+/*
+ * Setup the direct mapping of the physical memory at PAGE_OFFSET.
+ * This runs before bootmem is initialized and gets pages directly from
+ * the physical memory. To access them they are temporarily mapped.
+ */
+unsigned long __init_refok init_memory_mapping(unsigned long start,
+ unsigned long end)
+{
+ unsigned long page_size_mask = 0;
+ unsigned long start_pfn, end_pfn;
+ unsigned long pos;
+ unsigned long ret;
+
+ struct map_range mr[NR_RANGE_MR];
+ int nr_range, i;
+ int use_pse, use_gbpages;
+
+ printk(KERN_INFO "init_memory_mapping: %016lx-%016lx\n", start, end);
+
+ if (!after_bootmem)
+ init_gbpages();
+
+#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.
+ */
+ use_pse = use_gbpages = 0;
+#else
+ use_pse = cpu_has_pse;
+ use_gbpages = direct_gbpages;
+#endif
+
+#ifdef CONFIG_X86_32
+#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);
+ __supported_pte_mask |= _PAGE_GLOBAL;
+ }
+#endif
+
+ if (use_gbpages)
+ page_size_mask |= 1 << PG_LEVEL_1G;
+ if (use_pse)
+ page_size_mask |= 1 << PG_LEVEL_2M;
+
+ memset(mr, 0, sizeof(mr));
+ nr_range = 0;
+
+ /* head if not big page alignment ? */
+ start_pfn = start >> PAGE_SHIFT;
+ pos = start_pfn << PAGE_SHIFT;
+#ifdef CONFIG_X86_32
+ /*
+ * 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 (pos == 0)
+ end_pfn = 1<<(PMD_SHIFT - PAGE_SHIFT);
+ else
+ end_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#else /* CONFIG_X86_64 */
+ end_pfn = ((pos + (PMD_SIZE - 1)) >> PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#endif
+ if (end_pfn > (end >> PAGE_SHIFT))
+ end_pfn = end >> PAGE_SHIFT;
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+ /* big page (2M) range */
+ start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+#ifdef CONFIG_X86_32
+ end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+#else /* CONFIG_X86_64 */
+ end_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
+ << (PUD_SHIFT - PAGE_SHIFT);
+ if (end_pfn > ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT)))
+ end_pfn = ((end>>PMD_SHIFT)<<(PMD_SHIFT - PAGE_SHIFT));
+#endif
+
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask & (1<<PG_LEVEL_2M));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+#ifdef CONFIG_X86_64
+ /* big page (1G) range */
+ start_pfn = ((pos + (PUD_SIZE - 1))>>PUD_SHIFT)
+ << (PUD_SHIFT - PAGE_SHIFT);
+ end_pfn = (end >> PUD_SHIFT) << (PUD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask &
+ ((1<<PG_LEVEL_2M)|(1<<PG_LEVEL_1G)));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+
+ /* tail is not big page (1G) alignment */
+ start_pfn = ((pos + (PMD_SIZE - 1))>>PMD_SHIFT)
+ << (PMD_SHIFT - PAGE_SHIFT);
+ end_pfn = (end >> PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+ if (start_pfn < end_pfn) {
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn,
+ page_size_mask & (1<<PG_LEVEL_2M));
+ pos = end_pfn << PAGE_SHIFT;
+ }
+#endif
+
+ /* tail is not big page (2M) alignment */
+ start_pfn = pos>>PAGE_SHIFT;
+ end_pfn = end>>PAGE_SHIFT;
+ nr_range = save_mr(mr, nr_range, start_pfn, end_pfn, 0);
+
+ /* try to merge same page size and continuous */
+ for (i = 0; nr_range > 1 && i < nr_range - 1; i++) {
+ unsigned long old_start;
+ if (mr[i].end != mr[i+1].start ||
+ mr[i].page_size_mask != mr[i+1].page_size_mask)
+ continue;
+ /* move it */
+ old_start = mr[i].start;
+ memmove(&mr[i], &mr[i+1],
+ (nr_range - 1 - i) * sizeof(struct map_range));
+ mr[i--].start = old_start;
+ nr_range--;
+ }
+
+ for (i = 0; i < nr_range; i++)
+ printk(KERN_DEBUG " %010lx - %010lx page %s\n",
+ mr[i].start, mr[i].end,
+ (mr[i].page_size_mask & (1<<PG_LEVEL_1G))?"1G":(
+ (mr[i].page_size_mask & (1<<PG_LEVEL_2M))?"2M":"4k"));
+
+ /*
+ * Find space for the kernel direct mapping tables.
+ *
+ * Later we should allocate these tables in the local node of the
+ * memory mapped. Unfortunately this is done currently before the
+ * nodes are discovered.
+ */
+ if (!after_bootmem)
+ find_early_table_space(end, use_pse, use_gbpages);
+
+#ifdef CONFIG_X86_32
+ for (i = 0; i < nr_range; i++)
+ kernel_physical_mapping_init(
+ mr[i].start >> PAGE_SHIFT,
+ mr[i].end >> PAGE_SHIFT,
+ mr[i].page_size_mask == (1<<PG_LEVEL_2M));
+ ret = end;
+#else /* CONFIG_X86_64 */
+ for (i = 0; i < nr_range; i++)
+ ret = kernel_physical_mapping_init(mr[i].start, mr[i].end,
+ mr[i].page_size_mask);
+#endif
+
+#ifdef CONFIG_X86_32
+ early_ioremap_page_table_range_init();
+
+ load_cr3(swapper_pg_dir);
+#endif
+
+#ifdef CONFIG_X86_64
+ if (!after_bootmem)
+ mmu_cr4_features = read_cr4();
+#endif
+ __flush_tlb_all();
+
+ if (!after_bootmem && table_end > table_start)
+ reserve_early(table_start << PAGE_SHIFT,
+ table_end << PAGE_SHIFT, "PGTABLE");
+
+ if (!after_bootmem)
+ early_memtest(start, end);
+
+ return ret >> PAGE_SHIFT;
+}
+
/*
* devmem_is_allowed() checks to see if /dev/mem access to a certain address
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