1 /* 2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include "linux/bootmem.h" 7 #include "linux/mm.h" 8 #include "linux/pfn.h" 9 #include "asm/page.h" 10 #include "as-layout.h" 11 #include "init.h" 12 #include "kern.h" 13 #include "mem_user.h" 14 #include "os.h" 15 16 static int physmem_fd = -1; 17 18 /* Changed during early boot */ 19 unsigned long high_physmem; 20 21 extern unsigned long long physmem_size; 22 23 int __init init_maps(unsigned long physmem, unsigned long iomem, 24 unsigned long highmem) 25 { 26 struct page *p, *map; 27 unsigned long phys_len, phys_pages, highmem_len, highmem_pages; 28 unsigned long iomem_len, iomem_pages, total_len, total_pages; 29 int i; 30 31 phys_pages = physmem >> PAGE_SHIFT; 32 phys_len = phys_pages * sizeof(struct page); 33 34 iomem_pages = iomem >> PAGE_SHIFT; 35 iomem_len = iomem_pages * sizeof(struct page); 36 37 highmem_pages = highmem >> PAGE_SHIFT; 38 highmem_len = highmem_pages * sizeof(struct page); 39 40 total_pages = phys_pages + iomem_pages + highmem_pages; 41 total_len = phys_len + iomem_len + highmem_len; 42 43 map = alloc_bootmem_low_pages(total_len); 44 if (map == NULL) 45 return -ENOMEM; 46 47 for (i = 0; i < total_pages; i++) { 48 p = &map[i]; 49 memset(p, 0, sizeof(struct page)); 50 SetPageReserved(p); 51 INIT_LIST_HEAD(&p->lru); 52 } 53 54 max_mapnr = total_pages; 55 return 0; 56 } 57 58 void map_memory(unsigned long virt, unsigned long phys, unsigned long len, 59 int r, int w, int x) 60 { 61 __u64 offset; 62 int fd, err; 63 64 fd = phys_mapping(phys, &offset); 65 err = os_map_memory((void *) virt, fd, offset, len, r, w, x); 66 if (err) { 67 if (err == -ENOMEM) 68 printk(KERN_ERR "try increasing the host's " 69 "/proc/sys/vm/max_map_count to <physical " 70 "memory size>/4096\n"); 71 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, " 72 "err = %d\n", virt, fd, offset, len, r, w, x, err); 73 } 74 } 75 76 extern int __syscall_stub_start; 77 78 void __init setup_physmem(unsigned long start, unsigned long reserve_end, 79 unsigned long len, unsigned long long highmem) 80 { 81 unsigned long reserve = reserve_end - start; 82 int pfn = PFN_UP(__pa(reserve_end)); 83 int delta = (len - reserve) >> PAGE_SHIFT; 84 int err, offset, bootmap_size; 85 86 physmem_fd = create_mem_file(len + highmem); 87 88 offset = uml_reserved - uml_physmem; 89 err = os_map_memory((void *) uml_reserved, physmem_fd, offset, 90 len - offset, 1, 1, 1); 91 if (err < 0) { 92 printf("setup_physmem - mapping %ld bytes of memory at 0x%p " 93 "failed - errno = %d\n", len - offset, 94 (void *) uml_reserved, err); 95 exit(1); 96 } 97 98 /* 99 * Special kludge - This page will be mapped in to userspace processes 100 * from physmem_fd, so it needs to be written out there. 101 */ 102 os_seek_file(physmem_fd, __pa(&__syscall_stub_start)); 103 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE); 104 105 bootmap_size = init_bootmem(pfn, pfn + delta); 106 free_bootmem(__pa(reserve_end) + bootmap_size, 107 len - bootmap_size - reserve); 108 } 109 110 int phys_mapping(unsigned long phys, unsigned long long *offset_out) 111 { 112 int fd = -1; 113 114 if (phys < physmem_size) { 115 fd = physmem_fd; 116 *offset_out = phys; 117 } 118 else if (phys < __pa(end_iomem)) { 119 struct iomem_region *region = iomem_regions; 120 121 while (region != NULL) { 122 if ((phys >= region->phys) && 123 (phys < region->phys + region->size)) { 124 fd = region->fd; 125 *offset_out = phys - region->phys; 126 break; 127 } 128 region = region->next; 129 } 130 } 131 else if (phys < __pa(end_iomem) + highmem) { 132 fd = physmem_fd; 133 *offset_out = phys - iomem_size; 134 } 135 136 return fd; 137 } 138 139 static int __init uml_mem_setup(char *line, int *add) 140 { 141 char *retptr; 142 physmem_size = memparse(line,&retptr); 143 return 0; 144 } 145 __uml_setup("mem=", uml_mem_setup, 146 "mem=<Amount of desired ram>\n" 147 " This controls how much \"physical\" memory the kernel allocates\n" 148 " for the system. The size is specified as a number followed by\n" 149 " one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n" 150 " This is not related to the amount of memory in the host. It can\n" 151 " be more, and the excess, if it's ever used, will just be swapped out.\n" 152 " Example: mem=64M\n\n" 153 ); 154 155 extern int __init parse_iomem(char *str, int *add); 156 157 __uml_setup("iomem=", parse_iomem, 158 "iomem=<name>,<file>\n" 159 " Configure <file> as an IO memory region named <name>.\n\n" 160 ); 161 162 /* 163 * This list is constructed in parse_iomem and addresses filled in in 164 * setup_iomem, both of which run during early boot. Afterwards, it's 165 * unchanged. 166 */ 167 struct iomem_region *iomem_regions; 168 169 /* Initialized in parse_iomem and unchanged thereafter */ 170 int iomem_size; 171 172 unsigned long find_iomem(char *driver, unsigned long *len_out) 173 { 174 struct iomem_region *region = iomem_regions; 175 176 while (region != NULL) { 177 if (!strcmp(region->driver, driver)) { 178 *len_out = region->size; 179 return region->virt; 180 } 181 182 region = region->next; 183 } 184 185 return 0; 186 } 187 188 static int setup_iomem(void) 189 { 190 struct iomem_region *region = iomem_regions; 191 unsigned long iomem_start = high_physmem + PAGE_SIZE; 192 int err; 193 194 while (region != NULL) { 195 err = os_map_memory((void *) iomem_start, region->fd, 0, 196 region->size, 1, 1, 0); 197 if (err) 198 printk(KERN_ERR "Mapping iomem region for driver '%s' " 199 "failed, errno = %d\n", region->driver, -err); 200 else { 201 region->virt = iomem_start; 202 region->phys = __pa(region->virt); 203 } 204 205 iomem_start += region->size + PAGE_SIZE; 206 region = region->next; 207 } 208 209 return 0; 210 } 211 212 __initcall(setup_iomem); 213