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