Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux...

[sfrench/cifs-2.6.git] / arch / x86 / mm / init_32.c

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index ee1091a469641f95db2564c558827e972728ee37..baf7c4f643c86ec7e8a7101b2f3306551269bba7 100644 (file)
--- 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
  *
@@ -51,6 +50,8 @@
 
 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;
 
@@ -70,7 +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));
@@ -99,7 +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));
        }
@@ -179,8 +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;
 
@@ -194,6 +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);
@@ -208,6 +215,7 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base)
 
                                set_pte(pte, pfn_pte(pfn, prot));
                        }
+                       max_pfn_mapped = pfn;
                }
        }
 }
@@ -219,6 +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;
@@ -357,7 +384,7 @@ 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)
@@ -449,7 +476,7 @@ void zap_low_mappings(void)
         * 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
@@ -723,25 +750,17 @@ 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;