Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/mm/vmalloc.c | |
3 | * | |
4 | * Copyright (C) 1993 Linus Torvalds | |
5 | * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 | |
6 | * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000 | |
7 | * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002 | |
930fc45a | 8 | * Numa awareness, Christoph Lameter, SGI, June 2005 |
1da177e4 LT |
9 | */ |
10 | ||
11 | #include <linux/mm.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/highmem.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/spinlock.h> | |
16 | #include <linux/interrupt.h> | |
17 | ||
18 | #include <linux/vmalloc.h> | |
19 | ||
20 | #include <asm/uaccess.h> | |
21 | #include <asm/tlbflush.h> | |
22 | ||
23 | ||
24 | DEFINE_RWLOCK(vmlist_lock); | |
25 | struct vm_struct *vmlist; | |
26 | ||
b221385b AB |
27 | static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, |
28 | int node); | |
29 | ||
1da177e4 LT |
30 | static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) |
31 | { | |
32 | pte_t *pte; | |
33 | ||
34 | pte = pte_offset_kernel(pmd, addr); | |
35 | do { | |
36 | pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte); | |
37 | WARN_ON(!pte_none(ptent) && !pte_present(ptent)); | |
38 | } while (pte++, addr += PAGE_SIZE, addr != end); | |
39 | } | |
40 | ||
41 | static inline void vunmap_pmd_range(pud_t *pud, unsigned long addr, | |
42 | unsigned long end) | |
43 | { | |
44 | pmd_t *pmd; | |
45 | unsigned long next; | |
46 | ||
47 | pmd = pmd_offset(pud, addr); | |
48 | do { | |
49 | next = pmd_addr_end(addr, end); | |
50 | if (pmd_none_or_clear_bad(pmd)) | |
51 | continue; | |
52 | vunmap_pte_range(pmd, addr, next); | |
53 | } while (pmd++, addr = next, addr != end); | |
54 | } | |
55 | ||
56 | static inline void vunmap_pud_range(pgd_t *pgd, unsigned long addr, | |
57 | unsigned long end) | |
58 | { | |
59 | pud_t *pud; | |
60 | unsigned long next; | |
61 | ||
62 | pud = pud_offset(pgd, addr); | |
63 | do { | |
64 | next = pud_addr_end(addr, end); | |
65 | if (pud_none_or_clear_bad(pud)) | |
66 | continue; | |
67 | vunmap_pmd_range(pud, addr, next); | |
68 | } while (pud++, addr = next, addr != end); | |
69 | } | |
70 | ||
71 | void unmap_vm_area(struct vm_struct *area) | |
72 | { | |
73 | pgd_t *pgd; | |
74 | unsigned long next; | |
75 | unsigned long addr = (unsigned long) area->addr; | |
76 | unsigned long end = addr + area->size; | |
77 | ||
78 | BUG_ON(addr >= end); | |
79 | pgd = pgd_offset_k(addr); | |
80 | flush_cache_vunmap(addr, end); | |
81 | do { | |
82 | next = pgd_addr_end(addr, end); | |
83 | if (pgd_none_or_clear_bad(pgd)) | |
84 | continue; | |
85 | vunmap_pud_range(pgd, addr, next); | |
86 | } while (pgd++, addr = next, addr != end); | |
87 | flush_tlb_kernel_range((unsigned long) area->addr, end); | |
88 | } | |
89 | ||
90 | static int vmap_pte_range(pmd_t *pmd, unsigned long addr, | |
91 | unsigned long end, pgprot_t prot, struct page ***pages) | |
92 | { | |
93 | pte_t *pte; | |
94 | ||
872fec16 | 95 | pte = pte_alloc_kernel(pmd, addr); |
1da177e4 LT |
96 | if (!pte) |
97 | return -ENOMEM; | |
98 | do { | |
99 | struct page *page = **pages; | |
100 | WARN_ON(!pte_none(*pte)); | |
101 | if (!page) | |
102 | return -ENOMEM; | |
103 | set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); | |
104 | (*pages)++; | |
105 | } while (pte++, addr += PAGE_SIZE, addr != end); | |
106 | return 0; | |
107 | } | |
108 | ||
109 | static inline int vmap_pmd_range(pud_t *pud, unsigned long addr, | |
110 | unsigned long end, pgprot_t prot, struct page ***pages) | |
111 | { | |
112 | pmd_t *pmd; | |
113 | unsigned long next; | |
114 | ||
115 | pmd = pmd_alloc(&init_mm, pud, addr); | |
116 | if (!pmd) | |
117 | return -ENOMEM; | |
118 | do { | |
119 | next = pmd_addr_end(addr, end); | |
120 | if (vmap_pte_range(pmd, addr, next, prot, pages)) | |
121 | return -ENOMEM; | |
122 | } while (pmd++, addr = next, addr != end); | |
123 | return 0; | |
124 | } | |
125 | ||
126 | static inline int vmap_pud_range(pgd_t *pgd, unsigned long addr, | |
127 | unsigned long end, pgprot_t prot, struct page ***pages) | |
128 | { | |
129 | pud_t *pud; | |
130 | unsigned long next; | |
131 | ||
132 | pud = pud_alloc(&init_mm, pgd, addr); | |
133 | if (!pud) | |
134 | return -ENOMEM; | |
135 | do { | |
136 | next = pud_addr_end(addr, end); | |
137 | if (vmap_pmd_range(pud, addr, next, prot, pages)) | |
138 | return -ENOMEM; | |
139 | } while (pud++, addr = next, addr != end); | |
140 | return 0; | |
141 | } | |
142 | ||
143 | int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages) | |
144 | { | |
145 | pgd_t *pgd; | |
146 | unsigned long next; | |
147 | unsigned long addr = (unsigned long) area->addr; | |
148 | unsigned long end = addr + area->size - PAGE_SIZE; | |
149 | int err; | |
150 | ||
151 | BUG_ON(addr >= end); | |
152 | pgd = pgd_offset_k(addr); | |
1da177e4 LT |
153 | do { |
154 | next = pgd_addr_end(addr, end); | |
155 | err = vmap_pud_range(pgd, addr, next, prot, pages); | |
156 | if (err) | |
157 | break; | |
158 | } while (pgd++, addr = next, addr != end); | |
1da177e4 LT |
159 | flush_cache_vmap((unsigned long) area->addr, end); |
160 | return err; | |
161 | } | |
162 | ||
930fc45a CL |
163 | struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, |
164 | unsigned long start, unsigned long end, int node) | |
1da177e4 LT |
165 | { |
166 | struct vm_struct **p, *tmp, *area; | |
167 | unsigned long align = 1; | |
168 | unsigned long addr; | |
169 | ||
170 | if (flags & VM_IOREMAP) { | |
171 | int bit = fls(size); | |
172 | ||
173 | if (bit > IOREMAP_MAX_ORDER) | |
174 | bit = IOREMAP_MAX_ORDER; | |
175 | else if (bit < PAGE_SHIFT) | |
176 | bit = PAGE_SHIFT; | |
177 | ||
178 | align = 1ul << bit; | |
179 | } | |
180 | addr = ALIGN(start, align); | |
181 | size = PAGE_ALIGN(size); | |
182 | ||
930fc45a | 183 | area = kmalloc_node(sizeof(*area), GFP_KERNEL, node); |
1da177e4 LT |
184 | if (unlikely(!area)) |
185 | return NULL; | |
186 | ||
187 | if (unlikely(!size)) { | |
188 | kfree (area); | |
189 | return NULL; | |
190 | } | |
191 | ||
192 | /* | |
193 | * We always allocate a guard page. | |
194 | */ | |
195 | size += PAGE_SIZE; | |
196 | ||
197 | write_lock(&vmlist_lock); | |
198 | for (p = &vmlist; (tmp = *p) != NULL ;p = &tmp->next) { | |
199 | if ((unsigned long)tmp->addr < addr) { | |
200 | if((unsigned long)tmp->addr + tmp->size >= addr) | |
201 | addr = ALIGN(tmp->size + | |
202 | (unsigned long)tmp->addr, align); | |
203 | continue; | |
204 | } | |
205 | if ((size + addr) < addr) | |
206 | goto out; | |
207 | if (size + addr <= (unsigned long)tmp->addr) | |
208 | goto found; | |
209 | addr = ALIGN(tmp->size + (unsigned long)tmp->addr, align); | |
210 | if (addr > end - size) | |
211 | goto out; | |
212 | } | |
213 | ||
214 | found: | |
215 | area->next = *p; | |
216 | *p = area; | |
217 | ||
218 | area->flags = flags; | |
219 | area->addr = (void *)addr; | |
220 | area->size = size; | |
221 | area->pages = NULL; | |
222 | area->nr_pages = 0; | |
223 | area->phys_addr = 0; | |
224 | write_unlock(&vmlist_lock); | |
225 | ||
226 | return area; | |
227 | ||
228 | out: | |
229 | write_unlock(&vmlist_lock); | |
230 | kfree(area); | |
231 | if (printk_ratelimit()) | |
232 | printk(KERN_WARNING "allocation failed: out of vmalloc space - use vmalloc=<size> to increase size.\n"); | |
233 | return NULL; | |
234 | } | |
235 | ||
930fc45a CL |
236 | struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, |
237 | unsigned long start, unsigned long end) | |
238 | { | |
239 | return __get_vm_area_node(size, flags, start, end, -1); | |
240 | } | |
241 | ||
1da177e4 LT |
242 | /** |
243 | * get_vm_area - reserve a contingous kernel virtual area | |
244 | * | |
245 | * @size: size of the area | |
246 | * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC | |
247 | * | |
248 | * Search an area of @size in the kernel virtual mapping area, | |
249 | * and reserved it for out purposes. Returns the area descriptor | |
250 | * on success or %NULL on failure. | |
251 | */ | |
252 | struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) | |
253 | { | |
254 | return __get_vm_area(size, flags, VMALLOC_START, VMALLOC_END); | |
255 | } | |
256 | ||
930fc45a CL |
257 | struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, int node) |
258 | { | |
259 | return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node); | |
260 | } | |
261 | ||
83342314 NP |
262 | /* Caller must hold vmlist_lock */ |
263 | static struct vm_struct *__find_vm_area(void *addr) | |
264 | { | |
265 | struct vm_struct *tmp; | |
266 | ||
267 | for (tmp = vmlist; tmp != NULL; tmp = tmp->next) { | |
268 | if (tmp->addr == addr) | |
269 | break; | |
270 | } | |
271 | ||
272 | return tmp; | |
273 | } | |
274 | ||
7856dfeb AK |
275 | /* Caller must hold vmlist_lock */ |
276 | struct vm_struct *__remove_vm_area(void *addr) | |
1da177e4 LT |
277 | { |
278 | struct vm_struct **p, *tmp; | |
279 | ||
1da177e4 LT |
280 | for (p = &vmlist ; (tmp = *p) != NULL ;p = &tmp->next) { |
281 | if (tmp->addr == addr) | |
282 | goto found; | |
283 | } | |
1da177e4 LT |
284 | return NULL; |
285 | ||
286 | found: | |
287 | unmap_vm_area(tmp); | |
288 | *p = tmp->next; | |
1da177e4 LT |
289 | |
290 | /* | |
291 | * Remove the guard page. | |
292 | */ | |
293 | tmp->size -= PAGE_SIZE; | |
294 | return tmp; | |
295 | } | |
296 | ||
7856dfeb AK |
297 | /** |
298 | * remove_vm_area - find and remove a contingous kernel virtual area | |
299 | * | |
300 | * @addr: base address | |
301 | * | |
302 | * Search for the kernel VM area starting at @addr, and remove it. | |
303 | * This function returns the found VM area, but using it is NOT safe | |
304 | * on SMP machines, except for its size or flags. | |
305 | */ | |
306 | struct vm_struct *remove_vm_area(void *addr) | |
307 | { | |
308 | struct vm_struct *v; | |
309 | write_lock(&vmlist_lock); | |
310 | v = __remove_vm_area(addr); | |
311 | write_unlock(&vmlist_lock); | |
312 | return v; | |
313 | } | |
314 | ||
1da177e4 LT |
315 | void __vunmap(void *addr, int deallocate_pages) |
316 | { | |
317 | struct vm_struct *area; | |
318 | ||
319 | if (!addr) | |
320 | return; | |
321 | ||
322 | if ((PAGE_SIZE-1) & (unsigned long)addr) { | |
323 | printk(KERN_ERR "Trying to vfree() bad address (%p)\n", addr); | |
324 | WARN_ON(1); | |
325 | return; | |
326 | } | |
327 | ||
328 | area = remove_vm_area(addr); | |
329 | if (unlikely(!area)) { | |
330 | printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", | |
331 | addr); | |
332 | WARN_ON(1); | |
333 | return; | |
334 | } | |
335 | ||
9a11b49a IM |
336 | debug_check_no_locks_freed(addr, area->size); |
337 | ||
1da177e4 LT |
338 | if (deallocate_pages) { |
339 | int i; | |
340 | ||
341 | for (i = 0; i < area->nr_pages; i++) { | |
5aae277e | 342 | BUG_ON(!area->pages[i]); |
1da177e4 LT |
343 | __free_page(area->pages[i]); |
344 | } | |
345 | ||
8757d5fa | 346 | if (area->flags & VM_VPAGES) |
1da177e4 LT |
347 | vfree(area->pages); |
348 | else | |
349 | kfree(area->pages); | |
350 | } | |
351 | ||
352 | kfree(area); | |
353 | return; | |
354 | } | |
355 | ||
356 | /** | |
357 | * vfree - release memory allocated by vmalloc() | |
358 | * | |
359 | * @addr: memory base address | |
360 | * | |
361 | * Free the virtually contiguous memory area starting at @addr, as | |
80e93eff PE |
362 | * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is |
363 | * NULL, no operation is performed. | |
1da177e4 | 364 | * |
80e93eff | 365 | * Must not be called in interrupt context. |
1da177e4 LT |
366 | */ |
367 | void vfree(void *addr) | |
368 | { | |
369 | BUG_ON(in_interrupt()); | |
370 | __vunmap(addr, 1); | |
371 | } | |
1da177e4 LT |
372 | EXPORT_SYMBOL(vfree); |
373 | ||
374 | /** | |
375 | * vunmap - release virtual mapping obtained by vmap() | |
376 | * | |
377 | * @addr: memory base address | |
378 | * | |
379 | * Free the virtually contiguous memory area starting at @addr, | |
380 | * which was created from the page array passed to vmap(). | |
381 | * | |
80e93eff | 382 | * Must not be called in interrupt context. |
1da177e4 LT |
383 | */ |
384 | void vunmap(void *addr) | |
385 | { | |
386 | BUG_ON(in_interrupt()); | |
387 | __vunmap(addr, 0); | |
388 | } | |
1da177e4 LT |
389 | EXPORT_SYMBOL(vunmap); |
390 | ||
391 | /** | |
392 | * vmap - map an array of pages into virtually contiguous space | |
393 | * | |
394 | * @pages: array of page pointers | |
395 | * @count: number of pages to map | |
396 | * @flags: vm_area->flags | |
397 | * @prot: page protection for the mapping | |
398 | * | |
399 | * Maps @count pages from @pages into contiguous kernel virtual | |
400 | * space. | |
401 | */ | |
402 | void *vmap(struct page **pages, unsigned int count, | |
403 | unsigned long flags, pgprot_t prot) | |
404 | { | |
405 | struct vm_struct *area; | |
406 | ||
407 | if (count > num_physpages) | |
408 | return NULL; | |
409 | ||
410 | area = get_vm_area((count << PAGE_SHIFT), flags); | |
411 | if (!area) | |
412 | return NULL; | |
413 | if (map_vm_area(area, prot, &pages)) { | |
414 | vunmap(area->addr); | |
415 | return NULL; | |
416 | } | |
417 | ||
418 | return area->addr; | |
419 | } | |
1da177e4 LT |
420 | EXPORT_SYMBOL(vmap); |
421 | ||
930fc45a CL |
422 | void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, |
423 | pgprot_t prot, int node) | |
1da177e4 LT |
424 | { |
425 | struct page **pages; | |
426 | unsigned int nr_pages, array_size, i; | |
427 | ||
428 | nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT; | |
429 | array_size = (nr_pages * sizeof(struct page *)); | |
430 | ||
431 | area->nr_pages = nr_pages; | |
432 | /* Please note that the recursion is strictly bounded. */ | |
8757d5fa | 433 | if (array_size > PAGE_SIZE) { |
930fc45a | 434 | pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node); |
8757d5fa JK |
435 | area->flags |= VM_VPAGES; |
436 | } else | |
930fc45a | 437 | pages = kmalloc_node(array_size, (gfp_mask & ~__GFP_HIGHMEM), node); |
1da177e4 LT |
438 | area->pages = pages; |
439 | if (!area->pages) { | |
440 | remove_vm_area(area->addr); | |
441 | kfree(area); | |
442 | return NULL; | |
443 | } | |
444 | memset(area->pages, 0, array_size); | |
445 | ||
446 | for (i = 0; i < area->nr_pages; i++) { | |
930fc45a CL |
447 | if (node < 0) |
448 | area->pages[i] = alloc_page(gfp_mask); | |
449 | else | |
450 | area->pages[i] = alloc_pages_node(node, gfp_mask, 0); | |
1da177e4 LT |
451 | if (unlikely(!area->pages[i])) { |
452 | /* Successfully allocated i pages, free them in __vunmap() */ | |
453 | area->nr_pages = i; | |
454 | goto fail; | |
455 | } | |
456 | } | |
457 | ||
458 | if (map_vm_area(area, prot, &pages)) | |
459 | goto fail; | |
460 | return area->addr; | |
461 | ||
462 | fail: | |
463 | vfree(area->addr); | |
464 | return NULL; | |
465 | } | |
466 | ||
930fc45a CL |
467 | void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot) |
468 | { | |
469 | return __vmalloc_area_node(area, gfp_mask, prot, -1); | |
470 | } | |
471 | ||
1da177e4 | 472 | /** |
930fc45a | 473 | * __vmalloc_node - allocate virtually contiguous memory |
1da177e4 LT |
474 | * |
475 | * @size: allocation size | |
476 | * @gfp_mask: flags for the page level allocator | |
477 | * @prot: protection mask for the allocated pages | |
d44e0780 | 478 | * @node: node to use for allocation or -1 |
1da177e4 LT |
479 | * |
480 | * Allocate enough pages to cover @size from the page level | |
481 | * allocator with @gfp_mask flags. Map them into contiguous | |
482 | * kernel virtual space, using a pagetable protection of @prot. | |
483 | */ | |
b221385b AB |
484 | static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, |
485 | int node) | |
1da177e4 LT |
486 | { |
487 | struct vm_struct *area; | |
488 | ||
489 | size = PAGE_ALIGN(size); | |
490 | if (!size || (size >> PAGE_SHIFT) > num_physpages) | |
491 | return NULL; | |
492 | ||
930fc45a | 493 | area = get_vm_area_node(size, VM_ALLOC, node); |
1da177e4 LT |
494 | if (!area) |
495 | return NULL; | |
496 | ||
930fc45a | 497 | return __vmalloc_area_node(area, gfp_mask, prot, node); |
1da177e4 LT |
498 | } |
499 | ||
930fc45a CL |
500 | void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) |
501 | { | |
502 | return __vmalloc_node(size, gfp_mask, prot, -1); | |
503 | } | |
1da177e4 LT |
504 | EXPORT_SYMBOL(__vmalloc); |
505 | ||
506 | /** | |
507 | * vmalloc - allocate virtually contiguous memory | |
508 | * | |
509 | * @size: allocation size | |
510 | * | |
511 | * Allocate enough pages to cover @size from the page level | |
512 | * allocator and map them into contiguous kernel virtual space. | |
513 | * | |
514 | * For tight cotrol over page level allocator and protection flags | |
515 | * use __vmalloc() instead. | |
516 | */ | |
517 | void *vmalloc(unsigned long size) | |
518 | { | |
83342314 | 519 | return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL); |
1da177e4 | 520 | } |
1da177e4 LT |
521 | EXPORT_SYMBOL(vmalloc); |
522 | ||
83342314 NP |
523 | /** |
524 | * vmalloc_user - allocate virtually contiguous memory which has | |
525 | * been zeroed so it can be mapped to userspace without | |
526 | * leaking data. | |
527 | * | |
528 | * @size: allocation size | |
529 | */ | |
530 | void *vmalloc_user(unsigned long size) | |
531 | { | |
532 | struct vm_struct *area; | |
533 | void *ret; | |
534 | ||
535 | ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); | |
536 | write_lock(&vmlist_lock); | |
537 | area = __find_vm_area(ret); | |
538 | area->flags |= VM_USERMAP; | |
539 | write_unlock(&vmlist_lock); | |
540 | ||
541 | return ret; | |
542 | } | |
543 | EXPORT_SYMBOL(vmalloc_user); | |
544 | ||
930fc45a CL |
545 | /** |
546 | * vmalloc_node - allocate memory on a specific node | |
547 | * | |
548 | * @size: allocation size | |
d44e0780 | 549 | * @node: numa node |
930fc45a CL |
550 | * |
551 | * Allocate enough pages to cover @size from the page level | |
552 | * allocator and map them into contiguous kernel virtual space. | |
553 | * | |
554 | * For tight cotrol over page level allocator and protection flags | |
555 | * use __vmalloc() instead. | |
556 | */ | |
557 | void *vmalloc_node(unsigned long size, int node) | |
558 | { | |
83342314 | 559 | return __vmalloc_node(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, node); |
930fc45a CL |
560 | } |
561 | EXPORT_SYMBOL(vmalloc_node); | |
562 | ||
4dc3b16b PP |
563 | #ifndef PAGE_KERNEL_EXEC |
564 | # define PAGE_KERNEL_EXEC PAGE_KERNEL | |
565 | #endif | |
566 | ||
1da177e4 LT |
567 | /** |
568 | * vmalloc_exec - allocate virtually contiguous, executable memory | |
569 | * | |
570 | * @size: allocation size | |
571 | * | |
572 | * Kernel-internal function to allocate enough pages to cover @size | |
573 | * the page level allocator and map them into contiguous and | |
574 | * executable kernel virtual space. | |
575 | * | |
576 | * For tight cotrol over page level allocator and protection flags | |
577 | * use __vmalloc() instead. | |
578 | */ | |
579 | ||
1da177e4 LT |
580 | void *vmalloc_exec(unsigned long size) |
581 | { | |
582 | return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC); | |
583 | } | |
584 | ||
585 | /** | |
586 | * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) | |
587 | * | |
588 | * @size: allocation size | |
589 | * | |
590 | * Allocate enough 32bit PA addressable pages to cover @size from the | |
591 | * page level allocator and map them into contiguous kernel virtual space. | |
592 | */ | |
593 | void *vmalloc_32(unsigned long size) | |
594 | { | |
595 | return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL); | |
596 | } | |
1da177e4 LT |
597 | EXPORT_SYMBOL(vmalloc_32); |
598 | ||
83342314 NP |
599 | /** |
600 | * vmalloc_32_user - allocate virtually contiguous memory (32bit | |
601 | * addressable) which is zeroed so it can be | |
602 | * mapped to userspace without leaking data. | |
603 | * | |
604 | * @size: allocation size | |
605 | */ | |
606 | void *vmalloc_32_user(unsigned long size) | |
607 | { | |
608 | struct vm_struct *area; | |
609 | void *ret; | |
610 | ||
611 | ret = __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL); | |
612 | write_lock(&vmlist_lock); | |
613 | area = __find_vm_area(ret); | |
614 | area->flags |= VM_USERMAP; | |
615 | write_unlock(&vmlist_lock); | |
616 | ||
617 | return ret; | |
618 | } | |
619 | EXPORT_SYMBOL(vmalloc_32_user); | |
620 | ||
1da177e4 LT |
621 | long vread(char *buf, char *addr, unsigned long count) |
622 | { | |
623 | struct vm_struct *tmp; | |
624 | char *vaddr, *buf_start = buf; | |
625 | unsigned long n; | |
626 | ||
627 | /* Don't allow overflow */ | |
628 | if ((unsigned long) addr + count < count) | |
629 | count = -(unsigned long) addr; | |
630 | ||
631 | read_lock(&vmlist_lock); | |
632 | for (tmp = vmlist; tmp; tmp = tmp->next) { | |
633 | vaddr = (char *) tmp->addr; | |
634 | if (addr >= vaddr + tmp->size - PAGE_SIZE) | |
635 | continue; | |
636 | while (addr < vaddr) { | |
637 | if (count == 0) | |
638 | goto finished; | |
639 | *buf = '\0'; | |
640 | buf++; | |
641 | addr++; | |
642 | count--; | |
643 | } | |
644 | n = vaddr + tmp->size - PAGE_SIZE - addr; | |
645 | do { | |
646 | if (count == 0) | |
647 | goto finished; | |
648 | *buf = *addr; | |
649 | buf++; | |
650 | addr++; | |
651 | count--; | |
652 | } while (--n > 0); | |
653 | } | |
654 | finished: | |
655 | read_unlock(&vmlist_lock); | |
656 | return buf - buf_start; | |
657 | } | |
658 | ||
659 | long vwrite(char *buf, char *addr, unsigned long count) | |
660 | { | |
661 | struct vm_struct *tmp; | |
662 | char *vaddr, *buf_start = buf; | |
663 | unsigned long n; | |
664 | ||
665 | /* Don't allow overflow */ | |
666 | if ((unsigned long) addr + count < count) | |
667 | count = -(unsigned long) addr; | |
668 | ||
669 | read_lock(&vmlist_lock); | |
670 | for (tmp = vmlist; tmp; tmp = tmp->next) { | |
671 | vaddr = (char *) tmp->addr; | |
672 | if (addr >= vaddr + tmp->size - PAGE_SIZE) | |
673 | continue; | |
674 | while (addr < vaddr) { | |
675 | if (count == 0) | |
676 | goto finished; | |
677 | buf++; | |
678 | addr++; | |
679 | count--; | |
680 | } | |
681 | n = vaddr + tmp->size - PAGE_SIZE - addr; | |
682 | do { | |
683 | if (count == 0) | |
684 | goto finished; | |
685 | *addr = *buf; | |
686 | buf++; | |
687 | addr++; | |
688 | count--; | |
689 | } while (--n > 0); | |
690 | } | |
691 | finished: | |
692 | read_unlock(&vmlist_lock); | |
693 | return buf - buf_start; | |
694 | } | |
83342314 NP |
695 | |
696 | /** | |
697 | * remap_vmalloc_range - map vmalloc pages to userspace | |
698 | * | |
699 | * @vma: vma to cover (map full range of vma) | |
700 | * @addr: vmalloc memory | |
701 | * @pgoff: number of pages into addr before first page to map | |
702 | * @returns: 0 for success, -Exxx on failure | |
703 | * | |
704 | * This function checks that addr is a valid vmalloc'ed area, and | |
705 | * that it is big enough to cover the vma. Will return failure if | |
706 | * that criteria isn't met. | |
707 | * | |
708 | * Similar to remap_pfn_range (see mm/memory.c) | |
709 | */ | |
710 | int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, | |
711 | unsigned long pgoff) | |
712 | { | |
713 | struct vm_struct *area; | |
714 | unsigned long uaddr = vma->vm_start; | |
715 | unsigned long usize = vma->vm_end - vma->vm_start; | |
716 | int ret; | |
717 | ||
718 | if ((PAGE_SIZE-1) & (unsigned long)addr) | |
719 | return -EINVAL; | |
720 | ||
721 | read_lock(&vmlist_lock); | |
722 | area = __find_vm_area(addr); | |
723 | if (!area) | |
724 | goto out_einval_locked; | |
725 | ||
726 | if (!(area->flags & VM_USERMAP)) | |
727 | goto out_einval_locked; | |
728 | ||
729 | if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE) | |
730 | goto out_einval_locked; | |
731 | read_unlock(&vmlist_lock); | |
732 | ||
733 | addr += pgoff << PAGE_SHIFT; | |
734 | do { | |
735 | struct page *page = vmalloc_to_page(addr); | |
736 | ret = vm_insert_page(vma, uaddr, page); | |
737 | if (ret) | |
738 | return ret; | |
739 | ||
740 | uaddr += PAGE_SIZE; | |
741 | addr += PAGE_SIZE; | |
742 | usize -= PAGE_SIZE; | |
743 | } while (usize > 0); | |
744 | ||
745 | /* Prevent "things" like memory migration? VM_flags need a cleanup... */ | |
746 | vma->vm_flags |= VM_RESERVED; | |
747 | ||
748 | return ret; | |
749 | ||
750 | out_einval_locked: | |
751 | read_unlock(&vmlist_lock); | |
752 | return -EINVAL; | |
753 | } | |
754 | EXPORT_SYMBOL(remap_vmalloc_range); | |
755 |