1 /* 2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) 3 * Licensed under the GPL 4 */ 5 6 #include <linux/module.h> 7 #include <linux/bootmem.h> 8 #include <linux/mm.h> 9 #include <linux/pfn.h> 10 #include <asm/page.h> 11 #include <as-layout.h> 12 #include <init.h> 13 #include <kern.h> 14 #include <mem_user.h> 15 #include <os.h> 16 17 static int physmem_fd = -1; 18 19 /* Changed during early boot */ 20 unsigned long high_physmem; 21 EXPORT_SYMBOL(high_physmem); 22 23 extern unsigned long long physmem_size; 24 25 int __init init_maps(unsigned long physmem, unsigned long iomem, 26 unsigned long highmem) 27 { 28 struct page *p, *map; 29 unsigned long phys_len, phys_pages, highmem_len, highmem_pages; 30 unsigned long iomem_len, iomem_pages, total_len, total_pages; 31 int i; 32 33 phys_pages = physmem >> PAGE_SHIFT; 34 phys_len = phys_pages * sizeof(struct page); 35 36 iomem_pages = iomem >> PAGE_SHIFT; 37 iomem_len = iomem_pages * sizeof(struct page); 38 39 highmem_pages = highmem >> PAGE_SHIFT; 40 highmem_len = highmem_pages * sizeof(struct page); 41 42 total_pages = phys_pages + iomem_pages + highmem_pages; 43 total_len = phys_len + iomem_len + highmem_len; 44 45 map = alloc_bootmem_low_pages(total_len); 46 if (map == NULL) 47 return -ENOMEM; 48 49 for (i = 0; i < total_pages; i++) { 50 p = &map[i]; 51 memset(p, 0, sizeof(struct page)); 52 SetPageReserved(p); 53 INIT_LIST_HEAD(&p->lru); 54 } 55 56 max_mapnr = total_pages; 57 return 0; 58 } 59 60 void map_memory(unsigned long virt, unsigned long phys, unsigned long len, 61 int r, int w, int x) 62 { 63 __u64 offset; 64 int fd, err; 65 66 fd = phys_mapping(phys, &offset); 67 err = os_map_memory((void *) virt, fd, offset, len, r, w, x); 68 if (err) { 69 if (err == -ENOMEM) 70 printk(KERN_ERR "try increasing the host's " 71 "/proc/sys/vm/max_map_count to <physical " 72 "memory size>/4096\n"); 73 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, " 74 "err = %d\n", virt, fd, offset, len, r, w, x, err); 75 } 76 } 77 78 extern int __syscall_stub_start; 79 80 void __init setup_physmem(unsigned long start, unsigned long reserve_end, 81 unsigned long len, unsigned long long highmem) 82 { 83 unsigned long reserve = reserve_end - start; 84 int pfn = PFN_UP(__pa(reserve_end)); 85 int delta = (len - reserve) >> PAGE_SHIFT; 86 int err, offset, bootmap_size; 87 88 physmem_fd = create_mem_file(len + highmem); 89 90 offset = uml_reserved - uml_physmem; 91 err = os_map_memory((void *) uml_reserved, physmem_fd, offset, 92 len - offset, 1, 1, 1); 93 if (err < 0) { 94 printf("setup_physmem - mapping %ld bytes of memory at 0x%p " 95 "failed - errno = %d\n", len - offset, 96 (void *) uml_reserved, err); 97 exit(1); 98 } 99 100 /* 101 * Special kludge - This page will be mapped in to userspace processes 102 * from physmem_fd, so it needs to be written out there. 103 */ 104 os_seek_file(physmem_fd, __pa(&__syscall_stub_start)); 105 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE); 106 107 bootmap_size = init_bootmem(pfn, pfn + delta); 108 free_bootmem(__pa(reserve_end) + bootmap_size, 109 len - bootmap_size - reserve); 110 } 111 112 int phys_mapping(unsigned long phys, unsigned long long *offset_out) 113 { 114 int fd = -1; 115 116 if (phys < physmem_size) { 117 fd = physmem_fd; 118 *offset_out = phys; 119 } 120 else if (phys < __pa(end_iomem)) { 121 struct iomem_region *region = iomem_regions; 122 123 while (region != NULL) { 124 if ((phys >= region->phys) && 125 (phys < region->phys + region->size)) { 126 fd = region->fd; 127 *offset_out = phys - region->phys; 128 break; 129 } 130 region = region->next; 131 } 132 } 133 else if (phys < __pa(end_iomem) + highmem) { 134 fd = physmem_fd; 135 *offset_out = phys - iomem_size; 136 } 137 138 return fd; 139 } 140 141 static int __init uml_mem_setup(char *line, int *add) 142 { 143 char *retptr; 144 physmem_size = memparse(line,&retptr); 145 return 0; 146 } 147 __uml_setup("mem=", uml_mem_setup, 148 "mem=<Amount of desired ram>\n" 149 " This controls how much \"physical\" memory the kernel allocates\n" 150 " for the system. The size is specified as a number followed by\n" 151 " one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n" 152 " This is not related to the amount of memory in the host. It can\n" 153 " be more, and the excess, if it's ever used, will just be swapped out.\n" 154 " Example: mem=64M\n\n" 155 ); 156 157 extern int __init parse_iomem(char *str, int *add); 158 159 __uml_setup("iomem=", parse_iomem, 160 "iomem=<name>,<file>\n" 161 " Configure <file> as an IO memory region named <name>.\n\n" 162 ); 163 164 /* 165 * This list is constructed in parse_iomem and addresses filled in in 166 * setup_iomem, both of which run during early boot. Afterwards, it's 167 * unchanged. 168 */ 169 struct iomem_region *iomem_regions; 170 171 /* Initialized in parse_iomem and unchanged thereafter */ 172 int iomem_size; 173 174 unsigned long find_iomem(char *driver, unsigned long *len_out) 175 { 176 struct iomem_region *region = iomem_regions; 177 178 while (region != NULL) { 179 if (!strcmp(region->driver, driver)) { 180 *len_out = region->size; 181 return region->virt; 182 } 183 184 region = region->next; 185 } 186 187 return 0; 188 } 189 EXPORT_SYMBOL(find_iomem); 190 191 static int setup_iomem(void) 192 { 193 struct iomem_region *region = iomem_regions; 194 unsigned long iomem_start = high_physmem + PAGE_SIZE; 195 int err; 196 197 while (region != NULL) { 198 err = os_map_memory((void *) iomem_start, region->fd, 0, 199 region->size, 1, 1, 0); 200 if (err) 201 printk(KERN_ERR "Mapping iomem region for driver '%s' " 202 "failed, errno = %d\n", region->driver, -err); 203 else { 204 region->virt = iomem_start; 205 region->phys = __pa(region->virt); 206 } 207 208 iomem_start += region->size + PAGE_SIZE; 209 region = region->next; 210 } 211 212 return 0; 213 } 214 215 __initcall(setup_iomem); 216