Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #include <linux/highmem.h> |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 2 | #include <linux/module.h> |
Pekka Enberg | 867c5b52 | 2009-03-03 14:10:12 +0200 | [diff] [blame] | 3 | #include <linux/swap.h> /* for totalram_pages */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | |
| 5 | void *kmap(struct page *page) |
| 6 | { |
| 7 | might_sleep(); |
| 8 | if (!PageHighMem(page)) |
| 9 | return page_address(page); |
| 10 | return kmap_high(page); |
| 11 | } |
| 12 | |
| 13 | void kunmap(struct page *page) |
| 14 | { |
| 15 | if (in_interrupt()) |
| 16 | BUG(); |
| 17 | if (!PageHighMem(page)) |
| 18 | return; |
| 19 | kunmap_high(page); |
| 20 | } |
| 21 | |
Andrew Morton | 022eb43 | 2008-01-30 13:30:47 +0100 | [diff] [blame] | 22 | static void debug_kmap_atomic_prot(enum km_type type) |
| 23 | { |
| 24 | #ifdef CONFIG_DEBUG_HIGHMEM |
| 25 | static unsigned warn_count = 10; |
| 26 | |
| 27 | if (unlikely(warn_count == 0)) |
| 28 | return; |
| 29 | |
| 30 | if (unlikely(in_interrupt())) { |
| 31 | if (in_irq()) { |
| 32 | if (type != KM_IRQ0 && type != KM_IRQ1 && |
| 33 | type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ && |
| 34 | type != KM_BOUNCE_READ) { |
| 35 | WARN_ON(1); |
| 36 | warn_count--; |
| 37 | } |
| 38 | } else if (!irqs_disabled()) { /* softirq */ |
| 39 | if (type != KM_IRQ0 && type != KM_IRQ1 && |
| 40 | type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 && |
| 41 | type != KM_SKB_SUNRPC_DATA && |
| 42 | type != KM_SKB_DATA_SOFTIRQ && |
| 43 | type != KM_BOUNCE_READ) { |
| 44 | WARN_ON(1); |
| 45 | warn_count--; |
| 46 | } |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ || |
| 51 | type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ) { |
| 52 | if (!irqs_disabled()) { |
| 53 | WARN_ON(1); |
| 54 | warn_count--; |
| 55 | } |
| 56 | } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) { |
| 57 | if (irq_count() == 0 && !irqs_disabled()) { |
| 58 | WARN_ON(1); |
| 59 | warn_count--; |
| 60 | } |
| 61 | } |
| 62 | #endif |
| 63 | } |
| 64 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | /* |
| 66 | * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because |
| 67 | * no global lock is needed and because the kmap code must perform a global TLB |
| 68 | * invalidation when the kmap pool wraps. |
| 69 | * |
| 70 | * However when holding an atomic kmap is is not legal to sleep, so atomic |
| 71 | * kmaps are appropriate for short, tight code paths only. |
| 72 | */ |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 73 | void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | { |
| 75 | enum fixed_addresses idx; |
| 76 | unsigned long vaddr; |
Andrew Morton | 9c31205 | 2008-03-28 11:47:34 -0700 | [diff] [blame] | 77 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */ |
Peter Zijlstra | a866374 | 2006-12-06 20:32:20 -0800 | [diff] [blame] | 79 | pagefault_disable(); |
Ingo Molnar | 656dad3 | 2007-02-10 01:46:36 -0800 | [diff] [blame] | 80 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | if (!PageHighMem(page)) |
| 82 | return page_address(page); |
| 83 | |
Andrew Morton | 9c31205 | 2008-03-28 11:47:34 -0700 | [diff] [blame] | 84 | debug_kmap_atomic_prot(type); |
| 85 | |
Andrew Morton | 4150d3f | 2007-09-11 15:24:10 -0700 | [diff] [blame] | 86 | idx = type + KM_TYPE_NR*smp_processor_id(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); |
Andrew Morton | 4150d3f | 2007-09-11 15:24:10 -0700 | [diff] [blame] | 88 | BUG_ON(!pte_none(*(kmap_pte-idx))); |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 89 | set_pte(kmap_pte-idx, mk_pte(page, prot)); |
Zachary Amsden | 49f1971 | 2007-04-08 16:04:01 -0700 | [diff] [blame] | 90 | arch_flush_lazy_mmu_mode(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | |
Andrew Morton | 4150d3f | 2007-09-11 15:24:10 -0700 | [diff] [blame] | 92 | return (void *)vaddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | } |
| 94 | |
Jeremy Fitzhardinge | ce6234b | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 95 | void *kmap_atomic(struct page *page, enum km_type type) |
| 96 | { |
| 97 | return kmap_atomic_prot(page, type, kmap_prot); |
| 98 | } |
| 99 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | void kunmap_atomic(void *kvaddr, enum km_type type) |
| 101 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; |
| 103 | enum fixed_addresses idx = type + KM_TYPE_NR*smp_processor_id(); |
| 104 | |
Zachary Amsden | 23002d8 | 2006-09-30 23:29:35 -0700 | [diff] [blame] | 105 | /* |
| 106 | * Force other mappings to Oops if they'll try to access this pte |
| 107 | * without first remap it. Keeping stale mappings around is a bad idea |
| 108 | * also, in case the page changes cacheability attributes or becomes |
| 109 | * a protected page in a hypervisor. |
| 110 | */ |
Jeremy Fitzhardinge | 3b17979 | 2006-12-06 20:32:22 -0800 | [diff] [blame] | 111 | if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) |
| 112 | kpte_clear_flush(kmap_pte-idx, vaddr); |
| 113 | else { |
| 114 | #ifdef CONFIG_DEBUG_HIGHMEM |
| 115 | BUG_ON(vaddr < PAGE_OFFSET); |
| 116 | BUG_ON(vaddr >= (unsigned long)high_memory); |
| 117 | #endif |
| 118 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
Jeremy Fitzhardinge | 7b2f27f | 2007-05-02 19:27:15 +0200 | [diff] [blame] | 120 | arch_flush_lazy_mmu_mode(); |
Peter Zijlstra | a866374 | 2006-12-06 20:32:20 -0800 | [diff] [blame] | 121 | pagefault_enable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | } |
| 123 | |
Ingo Molnar | dd63fdc | 2009-03-13 03:20:49 +0100 | [diff] [blame^] | 124 | /* |
| 125 | * This is the same as kmap_atomic() but can map memory that doesn't |
Akinobu Mita | bb6d59c | 2009-03-11 23:33:18 +0900 | [diff] [blame] | 126 | * have a struct page associated with it. |
| 127 | */ |
| 128 | void *kmap_atomic_pfn(unsigned long pfn, enum km_type type) |
| 129 | { |
| 130 | return kmap_atomic_prot_pfn(pfn, type, kmap_prot); |
| 131 | } |
Eric Anholt | d1d8c92 | 2008-08-21 12:53:33 -0700 | [diff] [blame] | 132 | EXPORT_SYMBOL_GPL(kmap_atomic_pfn); /* temporarily in use by i915 GEM until vmap */ |
Vivek Goyal | 60e64d4 | 2005-06-25 14:58:19 -0700 | [diff] [blame] | 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | struct page *kmap_atomic_to_page(void *ptr) |
| 135 | { |
| 136 | unsigned long idx, vaddr = (unsigned long)ptr; |
| 137 | pte_t *pte; |
| 138 | |
| 139 | if (vaddr < FIXADDR_START) |
| 140 | return virt_to_page(ptr); |
| 141 | |
| 142 | idx = virt_to_fix(vaddr); |
| 143 | pte = kmap_pte - (idx - FIX_KMAP_BEGIN); |
| 144 | return pte_page(*pte); |
| 145 | } |
| 146 | |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 147 | EXPORT_SYMBOL(kmap); |
| 148 | EXPORT_SYMBOL(kunmap); |
| 149 | EXPORT_SYMBOL(kmap_atomic); |
| 150 | EXPORT_SYMBOL(kunmap_atomic); |
Pekka Enberg | 867c5b52 | 2009-03-03 14:10:12 +0200 | [diff] [blame] | 151 | |
Pekka Enberg | 867c5b52 | 2009-03-03 14:10:12 +0200 | [diff] [blame] | 152 | void __init set_highmem_pages_init(void) |
| 153 | { |
| 154 | struct zone *zone; |
| 155 | int nid; |
| 156 | |
| 157 | for_each_zone(zone) { |
| 158 | unsigned long zone_start_pfn, zone_end_pfn; |
| 159 | |
| 160 | if (!is_highmem(zone)) |
| 161 | continue; |
| 162 | |
| 163 | zone_start_pfn = zone->zone_start_pfn; |
| 164 | zone_end_pfn = zone_start_pfn + zone->spanned_pages; |
| 165 | |
| 166 | nid = zone_to_nid(zone); |
| 167 | printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n", |
| 168 | zone->name, nid, zone_start_pfn, zone_end_pfn); |
| 169 | |
| 170 | add_highpages_with_active_regions(nid, zone_start_pfn, |
| 171 | zone_end_pfn); |
| 172 | } |
| 173 | totalram_pages += totalhigh_pages; |
| 174 | } |