2 * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
3 * Licensed under the GPL
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 "user_util.h"
18 #include "mode_kern.h"
31 struct list_head list;
34 static struct rb_root phys_mappings = RB_ROOT;
36 static struct rb_node **find_rb(void *virt)
38 struct rb_node **n = &phys_mappings.rb_node;
42 d = rb_entry(*n, struct phys_desc, rb);
55 static struct phys_desc *find_phys_mapping(void *virt)
57 struct rb_node **n = find_rb(virt);
62 return rb_entry(*n, struct phys_desc, rb);
65 static void insert_phys_mapping(struct phys_desc *desc)
67 struct rb_node **n = find_rb(desc->virt);
70 panic("Physical remapping for %p already present",
73 rb_link_node(&desc->rb, rb_parent(*n), n);
74 rb_insert_color(&desc->rb, &phys_mappings);
77 LIST_HEAD(descriptor_mappings);
81 struct list_head list;
82 struct list_head pages;
85 static struct desc_mapping *find_mapping(int fd)
87 struct desc_mapping *desc;
88 struct list_head *ele;
90 list_for_each(ele, &descriptor_mappings){
91 desc = list_entry(ele, struct desc_mapping, list);
99 static struct desc_mapping *descriptor_mapping(int fd)
101 struct desc_mapping *desc;
103 desc = find_mapping(fd);
107 desc = kmalloc(sizeof(*desc), GFP_ATOMIC);
111 *desc = ((struct desc_mapping)
113 .list = LIST_HEAD_INIT(desc->list),
114 .pages = LIST_HEAD_INIT(desc->pages) });
115 list_add(&desc->list, &descriptor_mappings);
120 int physmem_subst_mapping(void *virt, int fd, __u64 offset, int w)
122 struct desc_mapping *fd_maps;
123 struct phys_desc *desc;
127 fd_maps = descriptor_mapping(fd);
132 desc = find_phys_mapping(virt);
134 panic("Address 0x%p is already substituted\n", virt);
137 desc = kmalloc(sizeof(*desc), GFP_ATOMIC);
141 *desc = ((struct phys_desc)
146 .list = LIST_HEAD_INIT(desc->list) });
147 insert_phys_mapping(desc);
149 list_add(&desc->list, &fd_maps->pages);
151 virt = (void *) ((unsigned long) virt & PAGE_MASK);
152 err = os_map_memory(virt, fd, offset, PAGE_SIZE, 1, w, 0);
156 rb_erase(&desc->rb, &phys_mappings);
162 static int physmem_fd = -1;
164 static void remove_mapping(struct phys_desc *desc)
166 void *virt = desc->virt;
169 rb_erase(&desc->rb, &phys_mappings);
170 list_del(&desc->list);
173 err = os_map_memory(virt, physmem_fd, __pa(virt), PAGE_SIZE, 1, 1, 0);
175 panic("Failed to unmap block device page from physical memory, "
179 int physmem_remove_mapping(void *virt)
181 struct phys_desc *desc;
183 virt = (void *) ((unsigned long) virt & PAGE_MASK);
184 desc = find_phys_mapping(virt);
188 remove_mapping(desc);
192 void physmem_forget_descriptor(int fd)
194 struct desc_mapping *desc;
195 struct phys_desc *page;
196 struct list_head *ele, *next;
201 desc = find_mapping(fd);
205 list_for_each_safe(ele, next, &desc->pages){
206 page = list_entry(ele, struct phys_desc, list);
207 offset = page->offset;
209 remove_mapping(page);
210 err = os_seek_file(fd, offset);
212 panic("physmem_forget_descriptor - failed to seek "
213 "to %lld in fd %d, error = %d\n",
215 err = os_read_file(fd, addr, PAGE_SIZE);
217 panic("physmem_forget_descriptor - failed to read "
218 "from fd %d to 0x%p, error = %d\n",
222 list_del(&desc->list);
226 EXPORT_SYMBOL(physmem_forget_descriptor);
227 EXPORT_SYMBOL(physmem_remove_mapping);
228 EXPORT_SYMBOL(physmem_subst_mapping);
230 void arch_free_page(struct page *page, int order)
235 for(i = 0; i < (1 << order); i++){
236 virt = __va(page_to_phys(page + i));
237 physmem_remove_mapping(virt);
241 int is_remapped(void *virt)
243 struct phys_desc *desc = find_phys_mapping(virt);
248 /* Changed during early boot */
249 unsigned long high_physmem;
251 extern unsigned long long physmem_size;
253 int init_maps(unsigned long physmem, unsigned long iomem, unsigned long highmem)
255 struct page *p, *map;
256 unsigned long phys_len, phys_pages, highmem_len, highmem_pages;
257 unsigned long iomem_len, iomem_pages, total_len, total_pages;
260 phys_pages = physmem >> PAGE_SHIFT;
261 phys_len = phys_pages * sizeof(struct page);
263 iomem_pages = iomem >> PAGE_SHIFT;
264 iomem_len = iomem_pages * sizeof(struct page);
266 highmem_pages = highmem >> PAGE_SHIFT;
267 highmem_len = highmem_pages * sizeof(struct page);
269 total_pages = phys_pages + iomem_pages + highmem_pages;
270 total_len = phys_len + iomem_len + highmem_len;
273 map = kmalloc(total_len, GFP_KERNEL);
275 map = vmalloc(total_len);
277 else map = alloc_bootmem_low_pages(total_len);
282 for(i = 0; i < total_pages; i++){
284 memset(p, 0, sizeof(struct page));
286 INIT_LIST_HEAD(&p->lru);
289 max_mapnr = total_pages;
293 /* Changed during early boot */
294 static unsigned long kmem_top = 0;
296 unsigned long get_kmem_end(void)
299 kmem_top = CHOOSE_MODE(kmem_end_tt, kmem_end_skas);
303 void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
309 fd = phys_mapping(phys, &offset);
310 err = os_map_memory((void *) virt, fd, offset, len, r, w, x);
313 printk("try increasing the host's "
314 "/proc/sys/vm/max_map_count to <physical "
315 "memory size>/4096\n");
316 panic("map_memory(0x%lx, %d, 0x%llx, %ld, %d, %d, %d) failed, "
317 "err = %d\n", virt, fd, offset, len, r, w, x, err);
321 extern int __syscall_stub_start;
323 void setup_physmem(unsigned long start, unsigned long reserve_end,
324 unsigned long len, unsigned long long highmem)
326 unsigned long reserve = reserve_end - start;
327 int pfn = PFN_UP(__pa(reserve_end));
328 int delta = (len - reserve) >> PAGE_SHIFT;
329 int err, offset, bootmap_size;
331 physmem_fd = create_mem_file(len + highmem);
333 offset = uml_reserved - uml_physmem;
334 err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
335 len - offset, 1, 1, 0);
337 os_print_error(err, "Mapping memory");
341 /* Special kludge - This page will be mapped in to userspace processes
342 * from physmem_fd, so it needs to be written out there.
344 os_seek_file(physmem_fd, __pa(&__syscall_stub_start));
345 os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE);
347 bootmap_size = init_bootmem(pfn, pfn + delta);
348 free_bootmem(__pa(reserve_end) + bootmap_size,
349 len - bootmap_size - reserve);
352 int phys_mapping(unsigned long phys, __u64 *offset_out)
354 struct phys_desc *desc = find_phys_mapping(__va(phys & PAGE_MASK));
359 *offset_out = desc->offset;
361 else if(phys < physmem_size){
365 else if(phys < __pa(end_iomem)){
366 struct iomem_region *region = iomem_regions;
368 while(region != NULL){
369 if((phys >= region->phys) &&
370 (phys < region->phys + region->size)){
372 *offset_out = phys - region->phys;
375 region = region->next;
378 else if(phys < __pa(end_iomem) + highmem){
380 *offset_out = phys - iomem_size;
386 static int __init uml_mem_setup(char *line, int *add)
389 physmem_size = memparse(line,&retptr);
392 __uml_setup("mem=", uml_mem_setup,
393 "mem=<Amount of desired ram>\n"
394 " This controls how much \"physical\" memory the kernel allocates\n"
395 " for the system. The size is specified as a number followed by\n"
396 " one of 'k', 'K', 'm', 'M', which have the obvious meanings.\n"
397 " This is not related to the amount of memory in the host. It can\n"
398 " be more, and the excess, if it's ever used, will just be swapped out.\n"
399 " Example: mem=64M\n\n"
402 extern int __init parse_iomem(char *str, int *add);
404 __uml_setup("iomem=", parse_iomem,
405 "iomem=<name>,<file>\n"
406 " Configure <file> as an IO memory region named <name>.\n\n"
410 * This list is constructed in parse_iomem and addresses filled in in
411 * setup_iomem, both of which run during early boot. Afterwards, it's
414 struct iomem_region *iomem_regions = NULL;
416 /* Initialized in parse_iomem */
419 unsigned long find_iomem(char *driver, unsigned long *len_out)
421 struct iomem_region *region = iomem_regions;
423 while(region != NULL){
424 if(!strcmp(region->driver, driver)){
425 *len_out = region->size;
429 region = region->next;
435 int setup_iomem(void)
437 struct iomem_region *region = iomem_regions;
438 unsigned long iomem_start = high_physmem + PAGE_SIZE;
441 while(region != NULL){
442 err = os_map_memory((void *) iomem_start, region->fd, 0,
443 region->size, 1, 1, 0);
445 printk("Mapping iomem region for driver '%s' failed, "
446 "errno = %d\n", region->driver, -err);
448 region->virt = iomem_start;
449 region->phys = __pa(region->virt);
452 iomem_start += region->size + PAGE_SIZE;
453 region = region->next;
459 __initcall(setup_iomem);