Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 1 | /* |
| 2 | * sparse memory mappings. |
| 3 | */ |
| 4 | #include <linux/config.h> |
| 5 | #include <linux/mm.h> |
| 6 | #include <linux/mmzone.h> |
| 7 | #include <linux/bootmem.h> |
| 8 | #include <linux/module.h> |
| 9 | #include <asm/dma.h> |
| 10 | |
| 11 | /* |
| 12 | * Permanent SPARSEMEM data: |
| 13 | * |
| 14 | * 1) mem_section - memory sections, mem_map's for valid memory |
| 15 | */ |
Bob Picco | 802f192 | 2005-09-03 15:54:26 -0700 | [diff] [blame^] | 16 | #ifdef CONFIG_ARCH_SPARSEMEM_EXTREME |
| 17 | struct mem_section *mem_section[NR_SECTION_ROOTS] |
| 18 | ____cacheline_maxaligned_in_smp; |
| 19 | |
| 20 | static void sparse_index_init(unsigned long section, int nid) |
| 21 | { |
| 22 | unsigned long root = SECTION_TO_ROOT(section); |
| 23 | |
| 24 | if (mem_section[root]) |
| 25 | return; |
| 26 | mem_section[root] = alloc_bootmem_node(NODE_DATA(nid), PAGE_SIZE); |
| 27 | if (mem_section[root]) |
| 28 | memset(mem_section[root], 0, PAGE_SIZE); |
| 29 | else |
| 30 | panic("memory_present: NO MEMORY\n"); |
| 31 | } |
| 32 | #else |
| 33 | struct mem_section mem_section[NR_MEM_SECTIONS] |
| 34 | ____cacheline_maxaligned_in_smp; |
| 35 | #endif |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 36 | EXPORT_SYMBOL(mem_section); |
| 37 | |
| 38 | /* Record a memory area against a node. */ |
| 39 | void memory_present(int nid, unsigned long start, unsigned long end) |
| 40 | { |
| 41 | unsigned long pfn; |
| 42 | |
| 43 | start &= PAGE_SECTION_MASK; |
| 44 | for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) { |
| 45 | unsigned long section = pfn_to_section_nr(pfn); |
Bob Picco | 802f192 | 2005-09-03 15:54:26 -0700 | [diff] [blame^] | 46 | struct mem_section *ms; |
| 47 | |
| 48 | sparse_index_init(section, nid); |
| 49 | |
| 50 | ms = __nr_to_section(section); |
| 51 | if (!ms->section_mem_map) |
| 52 | ms->section_mem_map = SECTION_MARKED_PRESENT; |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 53 | } |
| 54 | } |
| 55 | |
| 56 | /* |
| 57 | * Only used by the i386 NUMA architecures, but relatively |
| 58 | * generic code. |
| 59 | */ |
| 60 | unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn, |
| 61 | unsigned long end_pfn) |
| 62 | { |
| 63 | unsigned long pfn; |
| 64 | unsigned long nr_pages = 0; |
| 65 | |
| 66 | for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) { |
| 67 | if (nid != early_pfn_to_nid(pfn)) |
| 68 | continue; |
| 69 | |
| 70 | if (pfn_valid(pfn)) |
| 71 | nr_pages += PAGES_PER_SECTION; |
| 72 | } |
| 73 | |
| 74 | return nr_pages * sizeof(struct page); |
| 75 | } |
| 76 | |
| 77 | /* |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 78 | * Subtle, we encode the real pfn into the mem_map such that |
| 79 | * the identity pfn - section_mem_map will return the actual |
| 80 | * physical page frame number. |
| 81 | */ |
| 82 | static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum) |
| 83 | { |
| 84 | return (unsigned long)(mem_map - (section_nr_to_pfn(pnum))); |
| 85 | } |
| 86 | |
| 87 | /* |
| 88 | * We need this if we ever free the mem_maps. While not implemented yet, |
| 89 | * this function is included for parity with its sibling. |
| 90 | */ |
| 91 | static __attribute((unused)) |
| 92 | struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum) |
| 93 | { |
| 94 | return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum); |
| 95 | } |
| 96 | |
| 97 | static int sparse_init_one_section(struct mem_section *ms, |
| 98 | unsigned long pnum, struct page *mem_map) |
| 99 | { |
| 100 | if (!valid_section(ms)) |
| 101 | return -EINVAL; |
| 102 | |
| 103 | ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum); |
| 104 | |
| 105 | return 1; |
| 106 | } |
| 107 | |
| 108 | static struct page *sparse_early_mem_map_alloc(unsigned long pnum) |
| 109 | { |
| 110 | struct page *map; |
| 111 | int nid = early_pfn_to_nid(section_nr_to_pfn(pnum)); |
Bob Picco | 802f192 | 2005-09-03 15:54:26 -0700 | [diff] [blame^] | 112 | struct mem_section *ms = __nr_to_section(pnum); |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 113 | |
| 114 | map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION); |
| 115 | if (map) |
| 116 | return map; |
| 117 | |
| 118 | map = alloc_bootmem_node(NODE_DATA(nid), |
| 119 | sizeof(struct page) * PAGES_PER_SECTION); |
| 120 | if (map) |
| 121 | return map; |
| 122 | |
| 123 | printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__); |
Bob Picco | 802f192 | 2005-09-03 15:54:26 -0700 | [diff] [blame^] | 124 | ms->section_mem_map = 0; |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 125 | return NULL; |
| 126 | } |
| 127 | |
| 128 | /* |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 129 | * Allocate the accumulated non-linear sections, allocate a mem_map |
| 130 | * for each and record the physical to section mapping. |
| 131 | */ |
| 132 | void sparse_init(void) |
| 133 | { |
| 134 | unsigned long pnum; |
| 135 | struct page *map; |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 136 | |
| 137 | for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 138 | if (!valid_section_nr(pnum)) |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 139 | continue; |
| 140 | |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 141 | map = sparse_early_mem_map_alloc(pnum); |
Bob Picco | 802f192 | 2005-09-03 15:54:26 -0700 | [diff] [blame^] | 142 | if (!map) |
| 143 | continue; |
| 144 | sparse_init_one_section(__nr_to_section(pnum), pnum, map); |
Andy Whitcroft | d41dee3 | 2005-06-23 00:07:54 -0700 | [diff] [blame] | 145 | } |
| 146 | } |
Andy Whitcroft | 29751f6 | 2005-06-23 00:08:00 -0700 | [diff] [blame] | 147 | |
| 148 | /* |
| 149 | * returns the number of sections whose mem_maps were properly |
| 150 | * set. If this is <=0, then that means that the passed-in |
| 151 | * map was not consumed and must be freed. |
| 152 | */ |
| 153 | int sparse_add_one_section(unsigned long start_pfn, int nr_pages, struct page *map) |
| 154 | { |
| 155 | struct mem_section *ms = __pfn_to_section(start_pfn); |
| 156 | |
| 157 | if (ms->section_mem_map & SECTION_MARKED_PRESENT) |
| 158 | return -EEXIST; |
| 159 | |
| 160 | ms->section_mem_map |= SECTION_MARKED_PRESENT; |
| 161 | |
| 162 | return sparse_init_one_section(ms, pfn_to_section_nr(start_pfn), map); |
| 163 | } |