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 | ||
52fd24ca GP |
163 | static struct vm_struct *__get_vm_area_node(unsigned long size, unsigned long flags, |
164 | unsigned long start, unsigned long end, | |
165 | int node, gfp_t gfp_mask) | |
1da177e4 LT |
166 | { |
167 | struct vm_struct **p, *tmp, *area; | |
168 | unsigned long align = 1; | |
169 | unsigned long addr; | |
170 | ||
52fd24ca | 171 | BUG_ON(in_interrupt()); |
1da177e4 LT |
172 | if (flags & VM_IOREMAP) { |
173 | int bit = fls(size); | |
174 | ||
175 | if (bit > IOREMAP_MAX_ORDER) | |
176 | bit = IOREMAP_MAX_ORDER; | |
177 | else if (bit < PAGE_SHIFT) | |
178 | bit = PAGE_SHIFT; | |
179 | ||
180 | align = 1ul << bit; | |
181 | } | |
182 | addr = ALIGN(start, align); | |
183 | size = PAGE_ALIGN(size); | |
31be8309 OH |
184 | if (unlikely(!size)) |
185 | return NULL; | |
1da177e4 | 186 | |
5211e6e6 | 187 | area = kmalloc_node(sizeof(*area), gfp_mask & GFP_LEVEL_MASK, node); |
1da177e4 LT |
188 | if (unlikely(!area)) |
189 | return NULL; | |
190 | ||
1da177e4 LT |
191 | /* |
192 | * We always allocate a guard page. | |
193 | */ | |
194 | size += PAGE_SIZE; | |
195 | ||
196 | write_lock(&vmlist_lock); | |
197 | for (p = &vmlist; (tmp = *p) != NULL ;p = &tmp->next) { | |
198 | if ((unsigned long)tmp->addr < addr) { | |
199 | if((unsigned long)tmp->addr + tmp->size >= addr) | |
200 | addr = ALIGN(tmp->size + | |
201 | (unsigned long)tmp->addr, align); | |
202 | continue; | |
203 | } | |
204 | if ((size + addr) < addr) | |
205 | goto out; | |
206 | if (size + addr <= (unsigned long)tmp->addr) | |
207 | goto found; | |
208 | addr = ALIGN(tmp->size + (unsigned long)tmp->addr, align); | |
209 | if (addr > end - size) | |
210 | goto out; | |
211 | } | |
212 | ||
213 | found: | |
214 | area->next = *p; | |
215 | *p = area; | |
216 | ||
217 | area->flags = flags; | |
218 | area->addr = (void *)addr; | |
219 | area->size = size; | |
220 | area->pages = NULL; | |
221 | area->nr_pages = 0; | |
222 | area->phys_addr = 0; | |
223 | write_unlock(&vmlist_lock); | |
224 | ||
225 | return area; | |
226 | ||
227 | out: | |
228 | write_unlock(&vmlist_lock); | |
229 | kfree(area); | |
230 | if (printk_ratelimit()) | |
231 | printk(KERN_WARNING "allocation failed: out of vmalloc space - use vmalloc=<size> to increase size.\n"); | |
232 | return NULL; | |
233 | } | |
234 | ||
930fc45a CL |
235 | struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, |
236 | unsigned long start, unsigned long end) | |
237 | { | |
52fd24ca | 238 | return __get_vm_area_node(size, flags, start, end, -1, GFP_KERNEL); |
930fc45a CL |
239 | } |
240 | ||
1da177e4 LT |
241 | /** |
242 | * get_vm_area - reserve a contingous kernel virtual area | |
1da177e4 LT |
243 | * @size: size of the area |
244 | * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC | |
245 | * | |
246 | * Search an area of @size in the kernel virtual mapping area, | |
247 | * and reserved it for out purposes. Returns the area descriptor | |
248 | * on success or %NULL on failure. | |
249 | */ | |
250 | struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) | |
251 | { | |
252 | return __get_vm_area(size, flags, VMALLOC_START, VMALLOC_END); | |
253 | } | |
254 | ||
52fd24ca GP |
255 | struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags, |
256 | int node, gfp_t gfp_mask) | |
930fc45a | 257 | { |
52fd24ca GP |
258 | return __get_vm_area_node(size, flags, VMALLOC_START, VMALLOC_END, node, |
259 | gfp_mask); | |
930fc45a CL |
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 | 275 | /* Caller must hold vmlist_lock */ |
d24afc57 | 276 | static 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 | |
7856dfeb AK |
299 | * @addr: base address |
300 | * | |
301 | * Search for the kernel VM area starting at @addr, and remove it. | |
302 | * This function returns the found VM area, but using it is NOT safe | |
303 | * on SMP machines, except for its size or flags. | |
304 | */ | |
305 | struct vm_struct *remove_vm_area(void *addr) | |
306 | { | |
307 | struct vm_struct *v; | |
308 | write_lock(&vmlist_lock); | |
309 | v = __remove_vm_area(addr); | |
310 | write_unlock(&vmlist_lock); | |
311 | return v; | |
312 | } | |
313 | ||
1da177e4 LT |
314 | void __vunmap(void *addr, int deallocate_pages) |
315 | { | |
316 | struct vm_struct *area; | |
317 | ||
318 | if (!addr) | |
319 | return; | |
320 | ||
321 | if ((PAGE_SIZE-1) & (unsigned long)addr) { | |
322 | printk(KERN_ERR "Trying to vfree() bad address (%p)\n", addr); | |
323 | WARN_ON(1); | |
324 | return; | |
325 | } | |
326 | ||
327 | area = remove_vm_area(addr); | |
328 | if (unlikely(!area)) { | |
329 | printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", | |
330 | addr); | |
331 | WARN_ON(1); | |
332 | return; | |
333 | } | |
334 | ||
9a11b49a IM |
335 | debug_check_no_locks_freed(addr, area->size); |
336 | ||
1da177e4 LT |
337 | if (deallocate_pages) { |
338 | int i; | |
339 | ||
340 | for (i = 0; i < area->nr_pages; i++) { | |
5aae277e | 341 | BUG_ON(!area->pages[i]); |
1da177e4 LT |
342 | __free_page(area->pages[i]); |
343 | } | |
344 | ||
8757d5fa | 345 | if (area->flags & VM_VPAGES) |
1da177e4 LT |
346 | vfree(area->pages); |
347 | else | |
348 | kfree(area->pages); | |
349 | } | |
350 | ||
351 | kfree(area); | |
352 | return; | |
353 | } | |
354 | ||
355 | /** | |
356 | * vfree - release memory allocated by vmalloc() | |
1da177e4 LT |
357 | * @addr: memory base address |
358 | * | |
359 | * Free the virtually contiguous memory area starting at @addr, as | |
80e93eff PE |
360 | * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is |
361 | * NULL, no operation is performed. | |
1da177e4 | 362 | * |
80e93eff | 363 | * Must not be called in interrupt context. |
1da177e4 LT |
364 | */ |
365 | void vfree(void *addr) | |
366 | { | |
367 | BUG_ON(in_interrupt()); | |
368 | __vunmap(addr, 1); | |
369 | } | |
1da177e4 LT |
370 | EXPORT_SYMBOL(vfree); |
371 | ||
372 | /** | |
373 | * vunmap - release virtual mapping obtained by vmap() | |
1da177e4 LT |
374 | * @addr: memory base address |
375 | * | |
376 | * Free the virtually contiguous memory area starting at @addr, | |
377 | * which was created from the page array passed to vmap(). | |
378 | * | |
80e93eff | 379 | * Must not be called in interrupt context. |
1da177e4 LT |
380 | */ |
381 | void vunmap(void *addr) | |
382 | { | |
383 | BUG_ON(in_interrupt()); | |
384 | __vunmap(addr, 0); | |
385 | } | |
1da177e4 LT |
386 | EXPORT_SYMBOL(vunmap); |
387 | ||
388 | /** | |
389 | * vmap - map an array of pages into virtually contiguous space | |
1da177e4 LT |
390 | * @pages: array of page pointers |
391 | * @count: number of pages to map | |
392 | * @flags: vm_area->flags | |
393 | * @prot: page protection for the mapping | |
394 | * | |
395 | * Maps @count pages from @pages into contiguous kernel virtual | |
396 | * space. | |
397 | */ | |
398 | void *vmap(struct page **pages, unsigned int count, | |
399 | unsigned long flags, pgprot_t prot) | |
400 | { | |
401 | struct vm_struct *area; | |
402 | ||
403 | if (count > num_physpages) | |
404 | return NULL; | |
405 | ||
406 | area = get_vm_area((count << PAGE_SHIFT), flags); | |
407 | if (!area) | |
408 | return NULL; | |
409 | if (map_vm_area(area, prot, &pages)) { | |
410 | vunmap(area->addr); | |
411 | return NULL; | |
412 | } | |
413 | ||
414 | return area->addr; | |
415 | } | |
1da177e4 LT |
416 | EXPORT_SYMBOL(vmap); |
417 | ||
930fc45a CL |
418 | void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, |
419 | pgprot_t prot, int node) | |
1da177e4 LT |
420 | { |
421 | struct page **pages; | |
422 | unsigned int nr_pages, array_size, i; | |
423 | ||
424 | nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT; | |
425 | array_size = (nr_pages * sizeof(struct page *)); | |
426 | ||
427 | area->nr_pages = nr_pages; | |
428 | /* Please note that the recursion is strictly bounded. */ | |
8757d5fa | 429 | if (array_size > PAGE_SIZE) { |
930fc45a | 430 | pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node); |
8757d5fa | 431 | area->flags |= VM_VPAGES; |
286e1ea3 AM |
432 | } else { |
433 | pages = kmalloc_node(array_size, | |
434 | (gfp_mask & ~(__GFP_HIGHMEM | __GFP_ZERO)), | |
435 | node); | |
436 | } | |
1da177e4 LT |
437 | area->pages = pages; |
438 | if (!area->pages) { | |
439 | remove_vm_area(area->addr); | |
440 | kfree(area); | |
441 | return NULL; | |
442 | } | |
443 | memset(area->pages, 0, array_size); | |
444 | ||
445 | for (i = 0; i < area->nr_pages; i++) { | |
930fc45a CL |
446 | if (node < 0) |
447 | area->pages[i] = alloc_page(gfp_mask); | |
448 | else | |
449 | area->pages[i] = alloc_pages_node(node, gfp_mask, 0); | |
1da177e4 LT |
450 | if (unlikely(!area->pages[i])) { |
451 | /* Successfully allocated i pages, free them in __vunmap() */ | |
452 | area->nr_pages = i; | |
453 | goto fail; | |
454 | } | |
455 | } | |
456 | ||
457 | if (map_vm_area(area, prot, &pages)) | |
458 | goto fail; | |
459 | return area->addr; | |
460 | ||
461 | fail: | |
462 | vfree(area->addr); | |
463 | return NULL; | |
464 | } | |
465 | ||
930fc45a CL |
466 | void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot) |
467 | { | |
468 | return __vmalloc_area_node(area, gfp_mask, prot, -1); | |
469 | } | |
470 | ||
1da177e4 | 471 | /** |
930fc45a | 472 | * __vmalloc_node - allocate virtually contiguous memory |
1da177e4 LT |
473 | * @size: allocation size |
474 | * @gfp_mask: flags for the page level allocator | |
475 | * @prot: protection mask for the allocated pages | |
d44e0780 | 476 | * @node: node to use for allocation or -1 |
1da177e4 LT |
477 | * |
478 | * Allocate enough pages to cover @size from the page level | |
479 | * allocator with @gfp_mask flags. Map them into contiguous | |
480 | * kernel virtual space, using a pagetable protection of @prot. | |
481 | */ | |
b221385b AB |
482 | static void *__vmalloc_node(unsigned long size, gfp_t gfp_mask, pgprot_t prot, |
483 | int node) | |
1da177e4 LT |
484 | { |
485 | struct vm_struct *area; | |
486 | ||
487 | size = PAGE_ALIGN(size); | |
488 | if (!size || (size >> PAGE_SHIFT) > num_physpages) | |
489 | return NULL; | |
490 | ||
52fd24ca | 491 | area = get_vm_area_node(size, VM_ALLOC, node, gfp_mask); |
1da177e4 LT |
492 | if (!area) |
493 | return NULL; | |
494 | ||
930fc45a | 495 | return __vmalloc_area_node(area, gfp_mask, prot, node); |
1da177e4 LT |
496 | } |
497 | ||
930fc45a CL |
498 | void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) |
499 | { | |
500 | return __vmalloc_node(size, gfp_mask, prot, -1); | |
501 | } | |
1da177e4 LT |
502 | EXPORT_SYMBOL(__vmalloc); |
503 | ||
504 | /** | |
505 | * vmalloc - allocate virtually contiguous memory | |
1da177e4 | 506 | * @size: allocation size |
1da177e4 LT |
507 | * Allocate enough pages to cover @size from the page level |
508 | * allocator and map them into contiguous kernel virtual space. | |
509 | * | |
c1c8897f | 510 | * For tight control over page level allocator and protection flags |
1da177e4 LT |
511 | * use __vmalloc() instead. |
512 | */ | |
513 | void *vmalloc(unsigned long size) | |
514 | { | |
83342314 | 515 | return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL); |
1da177e4 | 516 | } |
1da177e4 LT |
517 | EXPORT_SYMBOL(vmalloc); |
518 | ||
83342314 | 519 | /** |
ead04089 REB |
520 | * vmalloc_user - allocate zeroed virtually contiguous memory for userspace |
521 | * @size: allocation size | |
83342314 | 522 | * |
ead04089 REB |
523 | * The resulting memory area is zeroed so it can be mapped to userspace |
524 | * without leaking data. | |
83342314 NP |
525 | */ |
526 | void *vmalloc_user(unsigned long size) | |
527 | { | |
528 | struct vm_struct *area; | |
529 | void *ret; | |
530 | ||
531 | ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, PAGE_KERNEL); | |
2b4ac44e ED |
532 | if (ret) { |
533 | write_lock(&vmlist_lock); | |
534 | area = __find_vm_area(ret); | |
535 | area->flags |= VM_USERMAP; | |
536 | write_unlock(&vmlist_lock); | |
537 | } | |
83342314 NP |
538 | return ret; |
539 | } | |
540 | EXPORT_SYMBOL(vmalloc_user); | |
541 | ||
930fc45a CL |
542 | /** |
543 | * vmalloc_node - allocate memory on a specific node | |
930fc45a | 544 | * @size: allocation size |
d44e0780 | 545 | * @node: numa node |
930fc45a CL |
546 | * |
547 | * Allocate enough pages to cover @size from the page level | |
548 | * allocator and map them into contiguous kernel virtual space. | |
549 | * | |
c1c8897f | 550 | * For tight control over page level allocator and protection flags |
930fc45a CL |
551 | * use __vmalloc() instead. |
552 | */ | |
553 | void *vmalloc_node(unsigned long size, int node) | |
554 | { | |
83342314 | 555 | return __vmalloc_node(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, node); |
930fc45a CL |
556 | } |
557 | EXPORT_SYMBOL(vmalloc_node); | |
558 | ||
4dc3b16b PP |
559 | #ifndef PAGE_KERNEL_EXEC |
560 | # define PAGE_KERNEL_EXEC PAGE_KERNEL | |
561 | #endif | |
562 | ||
1da177e4 LT |
563 | /** |
564 | * vmalloc_exec - allocate virtually contiguous, executable memory | |
1da177e4 LT |
565 | * @size: allocation size |
566 | * | |
567 | * Kernel-internal function to allocate enough pages to cover @size | |
568 | * the page level allocator and map them into contiguous and | |
569 | * executable kernel virtual space. | |
570 | * | |
c1c8897f | 571 | * For tight control over page level allocator and protection flags |
1da177e4 LT |
572 | * use __vmalloc() instead. |
573 | */ | |
574 | ||
1da177e4 LT |
575 | void *vmalloc_exec(unsigned long size) |
576 | { | |
577 | return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC); | |
578 | } | |
579 | ||
580 | /** | |
581 | * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) | |
1da177e4 LT |
582 | * @size: allocation size |
583 | * | |
584 | * Allocate enough 32bit PA addressable pages to cover @size from the | |
585 | * page level allocator and map them into contiguous kernel virtual space. | |
586 | */ | |
587 | void *vmalloc_32(unsigned long size) | |
588 | { | |
589 | return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL); | |
590 | } | |
1da177e4 LT |
591 | EXPORT_SYMBOL(vmalloc_32); |
592 | ||
83342314 | 593 | /** |
ead04089 | 594 | * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory |
83342314 | 595 | * @size: allocation size |
ead04089 REB |
596 | * |
597 | * The resulting memory area is 32bit addressable and zeroed so it can be | |
598 | * mapped to userspace without leaking data. | |
83342314 NP |
599 | */ |
600 | void *vmalloc_32_user(unsigned long size) | |
601 | { | |
602 | struct vm_struct *area; | |
603 | void *ret; | |
604 | ||
605 | ret = __vmalloc(size, GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL); | |
2b4ac44e ED |
606 | if (ret) { |
607 | write_lock(&vmlist_lock); | |
608 | area = __find_vm_area(ret); | |
609 | area->flags |= VM_USERMAP; | |
610 | write_unlock(&vmlist_lock); | |
611 | } | |
83342314 NP |
612 | return ret; |
613 | } | |
614 | EXPORT_SYMBOL(vmalloc_32_user); | |
615 | ||
1da177e4 LT |
616 | long vread(char *buf, char *addr, unsigned long count) |
617 | { | |
618 | struct vm_struct *tmp; | |
619 | char *vaddr, *buf_start = buf; | |
620 | unsigned long n; | |
621 | ||
622 | /* Don't allow overflow */ | |
623 | if ((unsigned long) addr + count < count) | |
624 | count = -(unsigned long) addr; | |
625 | ||
626 | read_lock(&vmlist_lock); | |
627 | for (tmp = vmlist; tmp; tmp = tmp->next) { | |
628 | vaddr = (char *) tmp->addr; | |
629 | if (addr >= vaddr + tmp->size - PAGE_SIZE) | |
630 | continue; | |
631 | while (addr < vaddr) { | |
632 | if (count == 0) | |
633 | goto finished; | |
634 | *buf = '\0'; | |
635 | buf++; | |
636 | addr++; | |
637 | count--; | |
638 | } | |
639 | n = vaddr + tmp->size - PAGE_SIZE - addr; | |
640 | do { | |
641 | if (count == 0) | |
642 | goto finished; | |
643 | *buf = *addr; | |
644 | buf++; | |
645 | addr++; | |
646 | count--; | |
647 | } while (--n > 0); | |
648 | } | |
649 | finished: | |
650 | read_unlock(&vmlist_lock); | |
651 | return buf - buf_start; | |
652 | } | |
653 | ||
654 | long vwrite(char *buf, char *addr, unsigned long count) | |
655 | { | |
656 | struct vm_struct *tmp; | |
657 | char *vaddr, *buf_start = buf; | |
658 | unsigned long n; | |
659 | ||
660 | /* Don't allow overflow */ | |
661 | if ((unsigned long) addr + count < count) | |
662 | count = -(unsigned long) addr; | |
663 | ||
664 | read_lock(&vmlist_lock); | |
665 | for (tmp = vmlist; tmp; tmp = tmp->next) { | |
666 | vaddr = (char *) tmp->addr; | |
667 | if (addr >= vaddr + tmp->size - PAGE_SIZE) | |
668 | continue; | |
669 | while (addr < vaddr) { | |
670 | if (count == 0) | |
671 | goto finished; | |
672 | buf++; | |
673 | addr++; | |
674 | count--; | |
675 | } | |
676 | n = vaddr + tmp->size - PAGE_SIZE - addr; | |
677 | do { | |
678 | if (count == 0) | |
679 | goto finished; | |
680 | *addr = *buf; | |
681 | buf++; | |
682 | addr++; | |
683 | count--; | |
684 | } while (--n > 0); | |
685 | } | |
686 | finished: | |
687 | read_unlock(&vmlist_lock); | |
688 | return buf - buf_start; | |
689 | } | |
83342314 NP |
690 | |
691 | /** | |
692 | * remap_vmalloc_range - map vmalloc pages to userspace | |
83342314 NP |
693 | * @vma: vma to cover (map full range of vma) |
694 | * @addr: vmalloc memory | |
695 | * @pgoff: number of pages into addr before first page to map | |
696 | * @returns: 0 for success, -Exxx on failure | |
697 | * | |
698 | * This function checks that addr is a valid vmalloc'ed area, and | |
699 | * that it is big enough to cover the vma. Will return failure if | |
700 | * that criteria isn't met. | |
701 | * | |
72fd4a35 | 702 | * Similar to remap_pfn_range() (see mm/memory.c) |
83342314 NP |
703 | */ |
704 | int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, | |
705 | unsigned long pgoff) | |
706 | { | |
707 | struct vm_struct *area; | |
708 | unsigned long uaddr = vma->vm_start; | |
709 | unsigned long usize = vma->vm_end - vma->vm_start; | |
710 | int ret; | |
711 | ||
712 | if ((PAGE_SIZE-1) & (unsigned long)addr) | |
713 | return -EINVAL; | |
714 | ||
715 | read_lock(&vmlist_lock); | |
716 | area = __find_vm_area(addr); | |
717 | if (!area) | |
718 | goto out_einval_locked; | |
719 | ||
720 | if (!(area->flags & VM_USERMAP)) | |
721 | goto out_einval_locked; | |
722 | ||
723 | if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE) | |
724 | goto out_einval_locked; | |
725 | read_unlock(&vmlist_lock); | |
726 | ||
727 | addr += pgoff << PAGE_SHIFT; | |
728 | do { | |
729 | struct page *page = vmalloc_to_page(addr); | |
730 | ret = vm_insert_page(vma, uaddr, page); | |
731 | if (ret) | |
732 | return ret; | |
733 | ||
734 | uaddr += PAGE_SIZE; | |
735 | addr += PAGE_SIZE; | |
736 | usize -= PAGE_SIZE; | |
737 | } while (usize > 0); | |
738 | ||
739 | /* Prevent "things" like memory migration? VM_flags need a cleanup... */ | |
740 | vma->vm_flags |= VM_RESERVED; | |
741 | ||
742 | return ret; | |
743 | ||
744 | out_einval_locked: | |
745 | read_unlock(&vmlist_lock); | |
746 | return -EINVAL; | |
747 | } | |
748 | EXPORT_SYMBOL(remap_vmalloc_range); | |
749 |