x86: clean up min_low_pfn
[safe/jmp/linux-2.6] / arch / x86 / mm / init_32.c
index 73dd060..9bb35cf 100644 (file)
@@ -1,5 +1,4 @@
 /*
- *  linux/arch/i386/mm/init.c
  *
  *  Copyright (C) 1995  Linus Torvalds
  *
@@ -51,7 +50,7 @@
 
 unsigned int __VMALLOC_RESERVE = 128 << 20;
 
-unsigned long end_pfn_map;
+unsigned long max_pfn_mapped;
 
 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
 unsigned long highstart_pfn, highend_pfn;
@@ -72,7 +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));
@@ -101,7 +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));
        }
@@ -163,6 +162,7 @@ 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;
 
        pgd_idx = pgd_index(PAGE_OFFSET);
        pgd = pgd_base + pgd_idx;
@@ -181,8 +181,13 @@ 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;
 
@@ -193,10 +198,11 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base)
                                    is_kernel_text(addr2))
                                        prot = PAGE_KERNEL_LARGE_EXEC;
 
+                               pages_2m++;
                                set_pmd(pmd, pfn_pmd(pfn, prot));
 
                                pfn += PTRS_PER_PTE;
-                               end_pfn_map = pfn;
+                               max_pfn_mapped = pfn;
                                continue;
                        }
                        pte = one_page_table_init(pmd);
@@ -209,16 +215,31 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base)
                                if (is_kernel_text(addr))
                                        prot = PAGE_KERNEL_EXEC;
 
+                               pages_4k++;
                                set_pte(pte, pfn_pte(pfn, prot));
                        }
-                       end_pfn_map = pfn;
+                       max_pfn_mapped = pfn;
                }
        }
+       update_page_count(PG_LEVEL_2M, pages_2m);
+       update_page_count(PG_LEVEL_4K, pages_4k);
 }
 
-static inline int page_kills_ppro(unsigned long pagenr)
+/*
+ * 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 >= 0x70000 && pagenr <= 0x7003F)
+       if (pagenr <= 256)
+               return 1;
+       if (!page_is_ram(pagenr))
                return 1;
        return 0;
 }
@@ -264,59 +285,62 @@ static void __init permanent_kmaps_init(pgd_t *pgd_base)
        pkmap_page_table = pte;
 }
 
-static void __meminit free_new_highpage(struct page *page)
+static void __init add_one_highpage_init(struct page *page, int pfn)
 {
+       ClearPageReserved(page);
        init_page_count(page);
        __free_page(page);
        totalhigh_pages++;
 }
 
-void __init add_one_highpage_init(struct page *page, int pfn, int bad_ppro)
-{
-       if (page_is_ram(pfn) && !(bad_ppro && page_kills_ppro(pfn))) {
-               ClearPageReserved(page);
-               free_new_highpage(page);
-       } else
-               SetPageReserved(page);
-}
+struct add_highpages_data {
+       unsigned long start_pfn;
+       unsigned long end_pfn;
+};
 
-static int __meminit
-add_one_highpage_hotplug(struct page *page, unsigned long pfn)
+static int __init add_highpages_work_fn(unsigned long start_pfn,
+                                        unsigned long end_pfn, void *datax)
 {
-       free_new_highpage(page);
-       totalram_pages++;
-#ifdef CONFIG_FLATMEM
-       max_mapnr = max(pfn, max_mapnr);
-#endif
-       num_physpages++;
+       int node_pfn;
+       struct page *page;
+       unsigned long final_start_pfn, final_end_pfn;
+       struct add_highpages_data *data;
+
+       data = (struct add_highpages_data *)datax;
+
+       final_start_pfn = max(start_pfn, data->start_pfn);
+       final_end_pfn = min(end_pfn, data->end_pfn);
+       if (final_start_pfn >= final_end_pfn)
+               return 0;
+
+       for (node_pfn = final_start_pfn; node_pfn < final_end_pfn;
+            node_pfn++) {
+               if (!pfn_valid(node_pfn))
+                       continue;
+               page = pfn_to_page(node_pfn);
+               add_one_highpage_init(page, node_pfn);
+       }
 
        return 0;
+
 }
 
-/*
- * Not currently handling the NUMA case.
- * Assuming single node and all memory that
- * has been added dynamically that would be
- * onlined here is in HIGHMEM.
- */
-void __meminit online_page(struct page *page)
+void __init add_highpages_with_active_regions(int nid, unsigned long start_pfn,
+                                             unsigned long end_pfn)
 {
-       ClearPageReserved(page);
-       add_one_highpage_hotplug(page, page_to_pfn(page));
+       struct add_highpages_data data;
+
+       data.start_pfn = start_pfn;
+       data.end_pfn = end_pfn;
+
+       work_with_active_regions(nid, add_highpages_work_fn, &data);
 }
 
 #ifndef CONFIG_NUMA
-static void __init set_highmem_pages_init(int bad_ppro)
+static void __init set_highmem_pages_init(void)
 {
-       int pfn;
+       add_highpages_with_active_regions(0, highstart_pfn, highend_pfn);
 
-       for (pfn = highstart_pfn; pfn < highend_pfn; pfn++) {
-               /*
-                * Holes under sparsemem might not have no mem_map[]:
-                */
-               if (pfn_valid(pfn))
-                       add_one_highpage_init(pfn_to_page(pfn), pfn, bad_ppro);
-       }
        totalram_pages += totalhigh_pages;
 }
 #endif /* !CONFIG_NUMA */
@@ -324,7 +348,7 @@ static void __init set_highmem_pages_init(int bad_ppro)
 #else
 # define kmap_init()                           do { } while (0)
 # define permanent_kmaps_init(pgd_base)                do { } while (0)
-# define set_highmem_pages_init(bad_ppro)      do { } while (0)
+# define set_highmem_pages_init()      do { } while (0)
 #endif /* CONFIG_HIGHMEM */
 
 pteval_t __PAGE_KERNEL = _PAGE_KERNEL;
@@ -361,7 +385,7 @@ 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)
@@ -445,15 +469,13 @@ void zap_low_mappings(void)
 {
        int i;
 
-       save_pg_dir();
-
        /*
         * Zap initial low-memory mappings.
         *
         * 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
@@ -518,6 +540,172 @@ static void __init set_nx(void)
 }
 #endif
 
+/* user-defined highmem size */
+static unsigned int highmem_pages = -1;
+
+/*
+ * highmem=size forces highmem to be exactly 'size' bytes.
+ * This works even on boxes that have no highmem otherwise.
+ * This also works to reduce highmem size on bigger boxes.
+ */
+static int __init parse_highmem(char *arg)
+{
+       if (!arg)
+               return -EINVAL;
+
+       highmem_pages = memparse(arg, &arg) >> PAGE_SHIFT;
+       return 0;
+}
+early_param("highmem", parse_highmem);
+
+/*
+ * Determine low and high memory ranges:
+ */
+void __init find_low_pfn_range(void)
+{
+       /* it could update max_pfn */
+
+       /* max_low_pfn is 0, we already have early_res support */
+
+       max_low_pfn = max_pfn;
+       if (max_low_pfn > MAXMEM_PFN) {
+               if (highmem_pages == -1)
+                       highmem_pages = max_pfn - MAXMEM_PFN;
+               if (highmem_pages + MAXMEM_PFN < max_pfn)
+                       max_pfn = MAXMEM_PFN + highmem_pages;
+               if (highmem_pages + MAXMEM_PFN > max_pfn) {
+                       printk(KERN_WARNING "only %luMB highmem pages "
+                               "available, ignoring highmem size of %uMB.\n",
+                               pages_to_mb(max_pfn - MAXMEM_PFN),
+                               pages_to_mb(highmem_pages));
+                       highmem_pages = 0;
+               }
+               max_low_pfn = MAXMEM_PFN;
+#ifndef CONFIG_HIGHMEM
+               /* Maximum memory usable is what is directly addressable */
+               printk(KERN_WARNING "Warning only %ldMB will be used.\n",
+                                       MAXMEM>>20);
+               if (max_pfn > MAX_NONPAE_PFN)
+                       printk(KERN_WARNING
+                                "Use a HIGHMEM64G enabled kernel.\n");
+               else
+                       printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
+               max_pfn = MAXMEM_PFN;
+#else /* !CONFIG_HIGHMEM */
+#ifndef CONFIG_HIGHMEM64G
+               if (max_pfn > MAX_NONPAE_PFN) {
+                       max_pfn = MAX_NONPAE_PFN;
+                       printk(KERN_WARNING "Warning only 4GB will be used."
+                               "Use a HIGHMEM64G enabled kernel.\n");
+               }
+#endif /* !CONFIG_HIGHMEM64G */
+#endif /* !CONFIG_HIGHMEM */
+       } else {
+               if (highmem_pages == -1)
+                       highmem_pages = 0;
+#ifdef CONFIG_HIGHMEM
+               if (highmem_pages >= max_pfn) {
+                       printk(KERN_ERR "highmem size specified (%uMB) is "
+                               "bigger than pages available (%luMB)!.\n",
+                               pages_to_mb(highmem_pages),
+                               pages_to_mb(max_pfn));
+                       highmem_pages = 0;
+               }
+               if (highmem_pages) {
+                       if (max_low_pfn - highmem_pages <
+                           64*1024*1024/PAGE_SIZE){
+                               printk(KERN_ERR "highmem size %uMB results in "
+                               "smaller than 64MB lowmem, ignoring it.\n"
+                                       , pages_to_mb(highmem_pages));
+                               highmem_pages = 0;
+                       }
+                       max_low_pfn -= highmem_pages;
+               }
+#else
+               if (highmem_pages)
+                       printk(KERN_ERR "ignoring highmem size on non-highmem"
+                                       " kernel!\n");
+#endif
+       }
+}
+
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+void __init initmem_init(unsigned long start_pfn,
+                                 unsigned long end_pfn)
+{
+#ifdef CONFIG_HIGHMEM
+       highstart_pfn = highend_pfn = max_pfn;
+       if (max_pfn > max_low_pfn)
+               highstart_pfn = max_low_pfn;
+       memory_present(0, 0, highend_pfn);
+       printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
+               pages_to_mb(highend_pfn - highstart_pfn));
+       num_physpages = highend_pfn;
+       high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
+#else
+       memory_present(0, 0, max_low_pfn);
+       num_physpages = max_low_pfn;
+       high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
+#endif
+#ifdef CONFIG_FLATMEM
+       max_mapnr = num_physpages;
+#endif
+       printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
+                       pages_to_mb(max_low_pfn));
+
+       setup_bootmem_allocator();
+}
+
+void __init zone_sizes_init(void)
+{
+       unsigned long max_zone_pfns[MAX_NR_ZONES];
+       memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+       max_zone_pfns[ZONE_DMA] =
+               virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
+       max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
+       remove_all_active_ranges();
+#ifdef CONFIG_HIGHMEM
+       max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
+       e820_register_active_regions(0, 0, highend_pfn);
+#else
+       e820_register_active_regions(0, 0, max_low_pfn);
+#endif
+
+       free_area_init_nodes(max_zone_pfns);
+}
+#endif /* !CONFIG_NEED_MULTIPLE_NODES */
+
+void __init setup_bootmem_allocator(void)
+{
+       int i;
+       unsigned long bootmap_size, bootmap;
+       /*
+        * Initialize the boot-time allocator (with low memory only):
+        */
+       bootmap_size = bootmem_bootmap_pages(max_low_pfn)<<PAGE_SHIFT;
+       bootmap = find_e820_area(min_low_pfn<<PAGE_SHIFT,
+                                max_pfn_mapped<<PAGE_SHIFT, bootmap_size,
+                                PAGE_SIZE);
+       if (bootmap == -1L)
+               panic("Cannot find bootmem map of size %ld\n", bootmap_size);
+       reserve_early(bootmap, bootmap + bootmap_size, "BOOTMAP");
+
+       /* don't touch min_low_pfn */
+       bootmap_size = init_bootmem_node(NODE_DATA(0), bootmap >> PAGE_SHIFT,
+                                        min_low_pfn, max_low_pfn);
+       printk(KERN_INFO "  mapped low ram: 0 - %08lx\n",
+                max_pfn_mapped<<PAGE_SHIFT);
+       printk(KERN_INFO "  low ram: %08lx - %08lx\n",
+                min_low_pfn<<PAGE_SHIFT, max_low_pfn<<PAGE_SHIFT);
+       printk(KERN_INFO "  bootmap %08lx - %08lx\n",
+                bootmap, bootmap + bootmap_size);
+       for_each_online_node(i)
+               free_bootmem_with_active_regions(i, max_low_pfn);
+       early_res_to_bootmem(0, max_low_pfn<<PAGE_SHIFT);
+
+}
+
+
 /*
  * paging_init() sets up the page tables - note that the first 8MB are
  * already mapped by head.S.
@@ -543,9 +731,9 @@ void __init paging_init(void)
 
 /*
  * Test if the WP bit works in supervisor mode. It isn't supported on 386's
- * and also on some strange 486's (NexGen etc.). All 586+'s are OK. This
- * used to involve black magic jumps to work around some nasty CPU bugs,
- * but fortunately the switch to using exceptions got rid of all that.
+ * and also on some strange 486's. All 586+'s are OK. This used to involve
+ * black magic jumps to work around some nasty CPU bugs, but fortunately the
+ * switch to using exceptions got rid of all that.
  */
 static void __init test_wp_bit(void)
 {
@@ -573,24 +761,11 @@ static struct kcore_list kcore_mem, kcore_vmalloc;
 void __init mem_init(void)
 {
        int codesize, reservedpages, datasize, initsize;
-       int tmp, bad_ppro;
+       int tmp;
 
 #ifdef CONFIG_FLATMEM
        BUG_ON(!mem_map);
 #endif
-       bad_ppro = ppro_with_ram_bug();
-
-#ifdef CONFIG_HIGHMEM
-       /* check that fixmap and pkmap do not overlap */
-       if (PKMAP_BASE + LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
-               printk(KERN_ERR
-                       "fixmap and kmap areas overlap - this will crash\n");
-               printk(KERN_ERR "pkstart: %lxh pkend: %lxh fixstart %lxh\n",
-                               PKMAP_BASE, PKMAP_BASE + LAST_PKMAP*PAGE_SIZE,
-                               FIXADDR_START);
-               BUG();
-       }
-#endif
        /* this will put all low memory onto the freelists */
        totalram_pages += free_all_bootmem();
 
@@ -602,7 +777,7 @@ void __init mem_init(void)
                if (page_is_ram(tmp) && PageReserved(pfn_to_page(tmp)))
                        reservedpages++;
 
-       set_highmem_pages_init(bad_ppro);
+       set_highmem_pages_init();
 
        codesize =  (unsigned long) &_etext - (unsigned long) &_text;
        datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
@@ -623,7 +798,6 @@ void __init mem_init(void)
                (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10))
               );
 
-#if 1 /* double-sanity-check paranoia */
        printk(KERN_INFO "virtual kernel memory layout:\n"
                "    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 #ifdef CONFIG_HIGHMEM
@@ -664,22 +838,13 @@ void __init mem_init(void)
 #endif
        BUG_ON(VMALLOC_START                            > VMALLOC_END);
        BUG_ON((unsigned long)high_memory               > VMALLOC_START);
-#endif /* double-sanity-check paranoia */
 
        if (boot_cpu_data.wp_works_ok < 0)
                test_wp_bit();
 
        cpa_init();
-
-       /*
-        * Subtle. SMP is doing it's boot stuff late (because it has to
-        * fork idle threads) - but it also needs low mappings for the
-        * protected-mode entry to work. We zap these entries only after
-        * the WP-bit has been tested.
-        */
-#ifndef CONFIG_SMP
+       save_pg_dir();
        zap_low_mappings();
-#endif
 }
 
 #ifdef CONFIG_MEMORY_HOTPLUG
@@ -801,3 +966,9 @@ void free_initrd_mem(unsigned long start, unsigned long end)
        free_init_pages("initrd memory", start, end);
 }
 #endif
+
+int __init reserve_bootmem_generic(unsigned long phys, unsigned long len,
+                                  int flags)
+{
+       return reserve_bootmem(phys, len, flags);
+}