1 /* 2 * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com) 3 * Licensed under the GPL 4 */ 5 6 #include "linux/mm.h" 7 #include "linux/rbtree.h" 8 #include "linux/slab.h" 9 #include "linux/vmalloc.h" 10 #include "linux/bootmem.h" 11 #include "linux/module.h" 12 #include "linux/pfn.h" 13 #include "asm/types.h" 14 #include "asm/pgtable.h" 15 #include "kern_util.h" 16 #include "as-layout.h" 17 #include "mode_kern.h" 18 #include "mem.h" 19 #include "mem_user.h" 20 #include "os.h" 21 #include "kern.h" 22 #include "init.h" 23 24 static int physmem_fd = -1; 25 26 /* Changed during early boot */ 27 unsigned long high_physmem; 28 29 extern unsigned long long physmem_size; 30 31 int __init init_maps(unsigned long physmem, unsigned long iomem, 32 unsigned long highmem) 33 { 34 struct page *p, *map; 35 unsigned long phys_len, phys_pages, highmem_len, highmem_pages; 36 unsigned long iomem_len, iomem_pages, total_len, total_pages; 37 int i; 38 39 phys_pages = physmem >> PAGE_SHIFT; 40 phys_len = phys_pages * sizeof(struct page); 41 42 iomem_pages = iomem >> PAGE_SHIFT; 43 iomem_len = iomem_pages * sizeof(struct page); 44 45 highmem_pages = highmem >> PAGE_SHIFT; 46 highmem_len = highmem_pages * sizeof(struct page); 47 48 total_pages = phys_pages + iomem_pages + highmem_pages; 49 total_len = phys_len + iomem_len + highmem_len; 50 51 map = alloc_bootmem_low_pages(total_len); 52 if(map == NULL) 53 return -ENOMEM; 54 55 for(i = 0; i < total_pages; i++){ 56 p = &map[i]; 57 memset(p, 0, sizeof(struct page)); 58 SetPageReserved(p); 59 INIT_LIST_HEAD(&p->lru); 60 } 61 62 max_mapnr = total_pages; 63 return 0; 64 } 65 66 /* Changed during early boot */ 67 static unsigned long kmem_top = 0; 68 69 unsigned long get_kmem_end(void) 70 { 71 if(kmem_top == 0) 72 kmem_top = CHOOSE_MODE(kmem_end_tt, kmem_end_skas); 73 return kmem_top; 74 } 75 76 void map_memory(unsigned long virt, unsigned long phys, unsigned long len, 77 int r, int w, int x) 78 { 79 __u64 offset; 80 int fd, err; 81 82 fd = phys_mapping(phys, &offset); 83 err = os_map_memory((void *) virt, fd, offset, len, r, w, x); 84 if(err) { 85 if(err == -ENOMEM) 86 printk("try increasing the host's " 87 "/proc/sys/vm/max_map_count to <physical " 88 "memory size>/4096\n"); 89 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, " 90 "err = %d\n", virt, fd, offset, len, r, w, x, err); 91 } 92 } 93 94 extern int __syscall_stub_start; 95 96 void __init setup_physmem(unsigned long start, unsigned long reserve_end, 97 unsigned long len, unsigned long long highmem) 98 { 99 unsigned long reserve = reserve_end - start; 100 int pfn = PFN_UP(__pa(reserve_end)); 101 int delta = (len - reserve) >> PAGE_SHIFT; 102 int err, offset, bootmap_size; 103 104 physmem_fd = create_mem_file(len + highmem); 105 106 offset = uml_reserved - uml_physmem; 107 err = os_map_memory((void *) uml_reserved, physmem_fd, offset, 108 len - offset, 1, 1, 0); 109 if(err < 0){ 110 os_print_error(err, "Mapping memory"); 111 exit(1); 112 } 113 114 /* Special kludge - This page will be mapped in to userspace processes 115 * from physmem_fd, so it needs to be written out there. 116 */ 117 os_seek_file(physmem_fd, __pa(&__syscall_stub_start)); 118 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE); 119 120 bootmap_size = init_bootmem(pfn, pfn + delta); 121 free_bootmem(__pa(reserve_end) + bootmap_size, 122 len - bootmap_size - reserve); 123 } 124 125 int phys_mapping(unsigned long phys, __u64 *offset_out) 126 { 127 int fd = -1; 128 129 if(phys < physmem_size){ 130 fd = physmem_fd; 131 *offset_out = phys; 132 } 133 else if(phys < __pa(end_iomem)){ 134 struct iomem_region *region = iomem_regions; 135 136 while(region != NULL){ 137 if((phys >= region->phys) && 138 (phys < region->phys + region->size)){ 139 fd = region->fd; 140 *offset_out = phys - region->phys; 141 break; 142 } 143 region = region->next; 144 } 145 } 146 else if(phys < __pa(end_iomem) + highmem){ 147 fd = physmem_fd; 148 *offset_out = phys - iomem_size; 149 } 150 151 return fd; 152 } 153 154 static int __init uml_mem_setup(char *line, int *add) 155 { 156 char *retptr; 157 physmem_size = memparse(line,&retptr); 158 return 0; 159 } 160 __uml_setup("mem=", uml_mem_setup, 161 "mem=<Amount of desired ram>\n" 162 " This controls how much \"physical\" memory the kernel allocates\n" 163 " for the system. The size is specified as a number followed by\n" 164 " one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n" 165 " This is not related to the amount of memory in the host. It can\n" 166 " be more, and the excess, if it's ever used, will just be swapped out.\n" 167 " Example: mem=64M\n\n" 168 ); 169 170 extern int __init parse_iomem(char *str, int *add); 171 172 __uml_setup("iomem=", parse_iomem, 173 "iomem=<name>,<file>\n" 174 " Configure <file> as an IO memory region named <name>.\n\n" 175 ); 176 177 /* 178 * This list is constructed in parse_iomem and addresses filled in in 179 * setup_iomem, both of which run during early boot. Afterwards, it's 180 * unchanged. 181 */ 182 struct iomem_region *iomem_regions = NULL; 183 184 /* Initialized in parse_iomem */ 185 int iomem_size = 0; 186 187 unsigned long find_iomem(char *driver, unsigned long *len_out) 188 { 189 struct iomem_region *region = iomem_regions; 190 191 while(region != NULL){ 192 if(!strcmp(region->driver, driver)){ 193 *len_out = region->size; 194 return region->virt; 195 } 196 197 region = region->next; 198 } 199 200 return 0; 201 } 202 203 int setup_iomem(void) 204 { 205 struct iomem_region *region = iomem_regions; 206 unsigned long iomem_start = high_physmem + PAGE_SIZE; 207 int err; 208 209 while(region != NULL){ 210 err = os_map_memory((void *) iomem_start, region->fd, 0, 211 region->size, 1, 1, 0); 212 if(err) 213 printk("Mapping iomem region for driver '%s' failed, " 214 "errno = %d\n", region->driver, -err); 215 else { 216 region->virt = iomem_start; 217 region->phys = __pa(region->virt); 218 } 219 220 iomem_start += region->size + PAGE_SIZE; 221 region = region->next; 222 } 223 224 return 0; 225 } 226 227 __initcall(setup_iomem); 228