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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 |
8 | * Numa awareness, Christoph Lameter, SGI, June 2005 |
9 | */ |
10 | |
11 | #include <linux/vmalloc.h> |
12 | #include <linux/mm.h> |
13 | #include <linux/module.h> |
14 | #include <linux/highmem.h> |
15 | #include <linux/sched.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/spinlock.h> |
18 | #include <linux/interrupt.h> |
19 | #include <linux/proc_fs.h> |
20 | #include <linux/seq_file.h> |
21 | #include <linux/debugobjects.h> |
22 | #include <linux/kallsyms.h> |
23 | #include <linux/list.h> |
24 | #include <linux/rbtree.h> |
25 | #include <linux/radix-tree.h> |
26 | #include <linux/rcupdate.h> |
27 | #include <linux/pfn.h> |
28 | #include <linux/kmemleak.h> |
29 | #include <linux/atomic.h> |
30 | #include <asm/uaccess.h> |
31 | #include <asm/tlbflush.h> |
32 | #include <asm/shmparam.h> |
33 | |
34 | /*** Page table manipulation functions ***/ |
35 | |
36 | static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end) |
37 | { |
38 | pte_t *pte; |
39 | |
40 | pte = pte_offset_kernel(pmd, addr); |
41 | do { |
42 | pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte); |
43 | WARN_ON(!pte_none(ptent) && !pte_present(ptent)); |
44 | } while (pte++, addr += PAGE_SIZE, addr != end); |
45 | } |
46 | |
47 | static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end) |
48 | { |
49 | pmd_t *pmd; |
50 | unsigned long next; |
51 | |
52 | pmd = pmd_offset(pud, addr); |
53 | do { |
54 | next = pmd_addr_end(addr, end); |
55 | if (pmd_none_or_clear_bad(pmd)) |
56 | continue; |
57 | vunmap_pte_range(pmd, addr, next); |
58 | } while (pmd++, addr = next, addr != end); |
59 | } |
60 | |
61 | static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end) |
62 | { |
63 | pud_t *pud; |
64 | unsigned long next; |
65 | |
66 | pud = pud_offset(pgd, addr); |
67 | do { |
68 | next = pud_addr_end(addr, end); |
69 | if (pud_none_or_clear_bad(pud)) |
70 | continue; |
71 | vunmap_pmd_range(pud, addr, next); |
72 | } while (pud++, addr = next, addr != end); |
73 | } |
74 | |
75 | static void vunmap_page_range(unsigned long addr, unsigned long end) |
76 | { |
77 | pgd_t *pgd; |
78 | unsigned long next; |
79 | |
80 | BUG_ON(addr >= end); |
81 | pgd = pgd_offset_k(addr); |
82 | do { |
83 | next = pgd_addr_end(addr, end); |
84 | if (pgd_none_or_clear_bad(pgd)) |
85 | continue; |
86 | vunmap_pud_range(pgd, addr, next); |
87 | } while (pgd++, addr = next, 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, int *nr) |
92 | { |
93 | pte_t *pte; |
94 | |
95 | /* |
96 | * nr is a running index into the array which helps higher level |
97 | * callers keep track of where we're up to. |
98 | */ |
99 | |
100 | pte = pte_alloc_kernel(pmd, addr); |
101 | if (!pte) |
102 | return -ENOMEM; |
103 | do { |
104 | struct page *page = pages[*nr]; |
105 | |
106 | if (WARN_ON(!pte_none(*pte))) |
107 | return -EBUSY; |
108 | if (WARN_ON(!page)) |
109 | return -ENOMEM; |
110 | set_pte_at(&init_mm, addr, pte, mk_pte(page, prot)); |
111 | (*nr)++; |
112 | } while (pte++, addr += PAGE_SIZE, addr != end); |
113 | return 0; |
114 | } |
115 | |
116 | static int vmap_pmd_range(pud_t *pud, unsigned long addr, |
117 | unsigned long end, pgprot_t prot, struct page **pages, int *nr) |
118 | { |
119 | pmd_t *pmd; |
120 | unsigned long next; |
121 | |
122 | pmd = pmd_alloc(&init_mm, pud, addr); |
123 | if (!pmd) |
124 | return -ENOMEM; |
125 | do { |
126 | next = pmd_addr_end(addr, end); |
127 | if (vmap_pte_range(pmd, addr, next, prot, pages, nr)) |
128 | return -ENOMEM; |
129 | } while (pmd++, addr = next, addr != end); |
130 | return 0; |
131 | } |
132 | |
133 | static int vmap_pud_range(pgd_t *pgd, unsigned long addr, |
134 | unsigned long end, pgprot_t prot, struct page **pages, int *nr) |
135 | { |
136 | pud_t *pud; |
137 | unsigned long next; |
138 | |
139 | pud = pud_alloc(&init_mm, pgd, addr); |
140 | if (!pud) |
141 | return -ENOMEM; |
142 | do { |
143 | next = pud_addr_end(addr, end); |
144 | if (vmap_pmd_range(pud, addr, next, prot, pages, nr)) |
145 | return -ENOMEM; |
146 | } while (pud++, addr = next, addr != end); |
147 | return 0; |
148 | } |
149 | |
150 | /* |
151 | * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and |
152 | * will have pfns corresponding to the "pages" array. |
153 | * |
154 | * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N] |
155 | */ |
156 | static int vmap_page_range_noflush(unsigned long start, unsigned long end, |
157 | pgprot_t prot, struct page **pages) |
158 | { |
159 | pgd_t *pgd; |
160 | unsigned long next; |
161 | unsigned long addr = start; |
162 | int err = 0; |
163 | int nr = 0; |
164 | |
165 | BUG_ON(addr >= end); |
166 | pgd = pgd_offset_k(addr); |
167 | do { |
168 | next = pgd_addr_end(addr, end); |
169 | err = vmap_pud_range(pgd, addr, next, prot, pages, &nr); |
170 | if (err) |
171 | return err; |
172 | } while (pgd++, addr = next, addr != end); |
173 | |
174 | return nr; |
175 | } |
176 | |
177 | static int vmap_page_range(unsigned long start, unsigned long end, |
178 | pgprot_t prot, struct page **pages) |
179 | { |
180 | int ret; |
181 | |
182 | ret = vmap_page_range_noflush(start, end, prot, pages); |
183 | flush_cache_vmap(start, end); |
184 | return ret; |
185 | } |
186 | |
187 | int is_vmalloc_or_module_addr(const void *x) |
188 | { |
189 | /* |
190 | * ARM, x86-64 and sparc64 put modules in a special place, |
191 | * and fall back on vmalloc() if that fails. Others |
192 | * just put it in the vmalloc space. |
193 | */ |
194 | #if defined(CONFIG_MODULES) && defined(MODULES_VADDR) |
195 | unsigned long addr = (unsigned long)x; |
196 | if (addr >= MODULES_VADDR && addr < MODULES_END) |
197 | return 1; |
198 | #endif |
199 | return is_vmalloc_addr(x); |
200 | } |
201 | |
202 | /* |
203 | * Walk a vmap address to the struct page it maps. |
204 | */ |
205 | struct page *vmalloc_to_page(const void *vmalloc_addr) |
206 | { |
207 | unsigned long addr = (unsigned long) vmalloc_addr; |
208 | struct page *page = NULL; |
209 | pgd_t *pgd = pgd_offset_k(addr); |
210 | |
211 | /* |
212 | * XXX we might need to change this if we add VIRTUAL_BUG_ON for |
213 | * architectures that do not vmalloc module space |
214 | */ |
215 | VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr)); |
216 | |
217 | if (!pgd_none(*pgd)) { |
218 | pud_t *pud = pud_offset(pgd, addr); |
219 | if (!pud_none(*pud)) { |
220 | pmd_t *pmd = pmd_offset(pud, addr); |
221 | if (!pmd_none(*pmd)) { |
222 | pte_t *ptep, pte; |
223 | |
224 | ptep = pte_offset_map(pmd, addr); |
225 | pte = *ptep; |
226 | if (pte_present(pte)) |
227 | page = pte_page(pte); |
228 | pte_unmap(ptep); |
229 | } |
230 | } |
231 | } |
232 | return page; |
233 | } |
234 | EXPORT_SYMBOL(vmalloc_to_page); |
235 | |
236 | /* |
237 | * Map a vmalloc()-space virtual address to the physical page frame number. |
238 | */ |
239 | unsigned long vmalloc_to_pfn(const void *vmalloc_addr) |
240 | { |
241 | return page_to_pfn(vmalloc_to_page(vmalloc_addr)); |
242 | } |
243 | EXPORT_SYMBOL(vmalloc_to_pfn); |
244 | |
245 | |
246 | /*** Global kva allocator ***/ |
247 | |
248 | #define VM_LAZY_FREE 0x01 |
249 | #define VM_LAZY_FREEING 0x02 |
250 | #define VM_VM_AREA 0x04 |
251 | |
252 | struct vmap_area { |
253 | unsigned long va_start; |
254 | unsigned long va_end; |
255 | unsigned long flags; |
256 | struct rb_node rb_node; /* address sorted rbtree */ |
257 | struct list_head list; /* address sorted list */ |
258 | struct list_head purge_list; /* "lazy purge" list */ |
259 | void *private; |
260 | struct rcu_head rcu_head; |
261 | }; |
262 | |
263 | static DEFINE_SPINLOCK(vmap_area_lock); |
264 | static LIST_HEAD(vmap_area_list); |
265 | static struct rb_root vmap_area_root = RB_ROOT; |
266 | |
267 | /* The vmap cache globals are protected by vmap_area_lock */ |
268 | static struct rb_node *free_vmap_cache; |
269 | static unsigned long cached_hole_size; |
270 | static unsigned long cached_vstart; |
271 | static unsigned long cached_align; |
272 | |
273 | static unsigned long vmap_area_pcpu_hole; |
274 | |
275 | static struct vmap_area *__find_vmap_area(unsigned long addr) |
276 | { |
277 | struct rb_node *n = vmap_area_root.rb_node; |
278 | |
279 | while (n) { |
280 | struct vmap_area *va; |
281 | |
282 | va = rb_entry(n, struct vmap_area, rb_node); |
283 | if (addr < va->va_start) |
284 | n = n->rb_left; |
285 | else if (addr > va->va_start) |
286 | n = n->rb_right; |
287 | else |
288 | return va; |
289 | } |
290 | |
291 | return NULL; |
292 | } |
293 | |
294 | static void __insert_vmap_area(struct vmap_area *va) |
295 | { |
296 | struct rb_node **p = &vmap_area_root.rb_node; |
297 | struct rb_node *parent = NULL; |
298 | struct rb_node *tmp; |
299 | |
300 | while (*p) { |
301 | struct vmap_area *tmp_va; |
302 | |
303 | parent = *p; |
304 | tmp_va = rb_entry(parent, struct vmap_area, rb_node); |
305 | if (va->va_start < tmp_va->va_end) |
306 | p = &(*p)->rb_left; |
307 | else if (va->va_end > tmp_va->va_start) |
308 | p = &(*p)->rb_right; |
309 | else |
310 | BUG(); |
311 | } |
312 | |
313 | rb_link_node(&va->rb_node, parent, p); |
314 | rb_insert_color(&va->rb_node, &vmap_area_root); |
315 | |
316 | /* address-sort this list so it is usable like the vmlist */ |
317 | tmp = rb_prev(&va->rb_node); |
318 | if (tmp) { |
319 | struct vmap_area *prev; |
320 | prev = rb_entry(tmp, struct vmap_area, rb_node); |
321 | list_add_rcu(&va->list, &prev->list); |
322 | } else |
323 | list_add_rcu(&va->list, &vmap_area_list); |
324 | } |
325 | |
326 | static void purge_vmap_area_lazy(void); |
327 | |
328 | /* |
329 | * Allocate a region of KVA of the specified size and alignment, within the |
330 | * vstart and vend. |
331 | */ |
332 | static struct vmap_area *alloc_vmap_area(unsigned long size, |
333 | unsigned long align, |
334 | unsigned long vstart, unsigned long vend, |
335 | int node, gfp_t gfp_mask) |
336 | { |
337 | struct vmap_area *va; |
338 | struct rb_node *n; |
339 | unsigned long addr; |
340 | int purged = 0; |
341 | struct vmap_area *first; |
342 | |
343 | BUG_ON(!size); |
344 | BUG_ON(size & ~PAGE_MASK); |
345 | BUG_ON(!is_power_of_2(align)); |
346 | |
347 | va = kmalloc_node(sizeof(struct vmap_area), |
348 | gfp_mask & GFP_RECLAIM_MASK, node); |
349 | if (unlikely(!va)) |
350 | return ERR_PTR(-ENOMEM); |
351 | |
352 | retry: |
353 | spin_lock(&vmap_area_lock); |
354 | /* |
355 | * Invalidate cache if we have more permissive parameters. |
356 | * cached_hole_size notes the largest hole noticed _below_ |
357 | * the vmap_area cached in free_vmap_cache: if size fits |
358 | * into that hole, we want to scan from vstart to reuse |
359 | * the hole instead of allocating above free_vmap_cache. |
360 | * Note that __free_vmap_area may update free_vmap_cache |
361 | * without updating cached_hole_size or cached_align. |
362 | */ |
363 | if (!free_vmap_cache || |
364 | size < cached_hole_size || |
365 | vstart < cached_vstart || |
366 | align < cached_align) { |
367 | nocache: |
368 | cached_hole_size = 0; |
369 | free_vmap_cache = NULL; |
370 | } |
371 | /* record if we encounter less permissive parameters */ |
372 | cached_vstart = vstart; |
373 | cached_align = align; |
374 | |
375 | /* find starting point for our search */ |
376 | if (free_vmap_cache) { |
377 | first = rb_entry(free_vmap_cache, struct vmap_area, rb_node); |
378 | addr = ALIGN(first->va_end, align); |
379 | if (addr < vstart) |
380 | goto nocache; |
381 | if (addr + size - 1 < addr) |
382 | goto overflow; |
383 | |
384 | } else { |
385 | addr = ALIGN(vstart, align); |
386 | if (addr + size - 1 < addr) |
387 | goto overflow; |
388 | |
389 | n = vmap_area_root.rb_node; |
390 | first = NULL; |
391 | |
392 | while (n) { |
393 | struct vmap_area *tmp; |
394 | tmp = rb_entry(n, struct vmap_area, rb_node); |
395 | if (tmp->va_end >= addr) { |
396 | first = tmp; |
397 | if (tmp->va_start <= addr) |
398 | break; |
399 | n = n->rb_left; |
400 | } else |
401 | n = n->rb_right; |
402 | } |
403 | |
404 | if (!first) |
405 | goto found; |
406 | } |
407 | |
408 | /* from the starting point, walk areas until a suitable hole is found */ |
409 | while (addr + size > first->va_start && addr + size <= vend) { |
410 | if (addr + cached_hole_size < first->va_start) |
411 | cached_hole_size = first->va_start - addr; |
412 | addr = ALIGN(first->va_end, align); |
413 | if (addr + size - 1 < addr) |
414 | goto overflow; |
415 | |
416 | n = rb_next(&first->rb_node); |
417 | if (n) |
418 | first = rb_entry(n, struct vmap_area, rb_node); |
419 | else |
420 | goto found; |
421 | } |
422 | |
423 | found: |
424 | if (addr + size > vend) |
425 | goto overflow; |
426 | |
427 | va->va_start = addr; |
428 | va->va_end = addr + size; |
429 | va->flags = 0; |
430 | __insert_vmap_area(va); |
431 | free_vmap_cache = &va->rb_node; |
432 | spin_unlock(&vmap_area_lock); |
433 | |
434 | BUG_ON(va->va_start & (align-1)); |
435 | BUG_ON(va->va_start < vstart); |
436 | BUG_ON(va->va_end > vend); |
437 | |
438 | return va; |
439 | |
440 | overflow: |
441 | spin_unlock(&vmap_area_lock); |
442 | if (!purged) { |
443 | purge_vmap_area_lazy(); |
444 | purged = 1; |
445 | goto retry; |
446 | } |
447 | if (printk_ratelimit()) |
448 | printk(KERN_WARNING |
449 | "vmap allocation for size %lu failed: " |
450 | "use vmalloc=<size> to increase size.\n", size); |
451 | kfree(va); |
452 | return ERR_PTR(-EBUSY); |
453 | } |
454 | |
455 | static void __free_vmap_area(struct vmap_area *va) |
456 | { |
457 | BUG_ON(RB_EMPTY_NODE(&va->rb_node)); |
458 | |
459 | if (free_vmap_cache) { |
460 | if (va->va_end < cached_vstart) { |
461 | free_vmap_cache = NULL; |
462 | } else { |
463 | struct vmap_area *cache; |
464 | cache = rb_entry(free_vmap_cache, struct vmap_area, rb_node); |
465 | if (va->va_start <= cache->va_start) { |
466 | free_vmap_cache = rb_prev(&va->rb_node); |
467 | /* |
468 | * We don't try to update cached_hole_size or |
469 | * cached_align, but it won't go very wrong. |
470 | */ |
471 | } |
472 | } |
473 | } |
474 | rb_erase(&va->rb_node, &vmap_area_root); |
475 | RB_CLEAR_NODE(&va->rb_node); |
476 | list_del_rcu(&va->list); |
477 | |
478 | /* |
479 | * Track the highest possible candidate for pcpu area |
480 | * allocation. Areas outside of vmalloc area can be returned |
481 | * here too, consider only end addresses which fall inside |
482 | * vmalloc area proper. |
483 | */ |
484 | if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END) |
485 | vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end); |
486 | |
487 | kfree_rcu(va, rcu_head); |
488 | } |
489 | |
490 | /* |
491 | * Free a region of KVA allocated by alloc_vmap_area |
492 | */ |
493 | static void free_vmap_area(struct vmap_area *va) |
494 | { |
495 | spin_lock(&vmap_area_lock); |
496 | __free_vmap_area(va); |
497 | spin_unlock(&vmap_area_lock); |
498 | } |
499 | |
500 | /* |
501 | * Clear the pagetable entries of a given vmap_area |
502 | */ |
503 | static void unmap_vmap_area(struct vmap_area *va) |
504 | { |
505 | vunmap_page_range(va->va_start, va->va_end); |
506 | } |
507 | |
508 | static void vmap_debug_free_range(unsigned long start, unsigned long end) |
509 | { |
510 | /* |
511 | * Unmap page tables and force a TLB flush immediately if |
512 | * CONFIG_DEBUG_PAGEALLOC is set. This catches use after free |
513 | * bugs similarly to those in linear kernel virtual address |
514 | * space after a page has been freed. |
515 | * |
516 | * All the lazy freeing logic is still retained, in order to |
517 | * minimise intrusiveness of this debugging feature. |
518 | * |
519 | * This is going to be *slow* (linear kernel virtual address |
520 | * debugging doesn't do a broadcast TLB flush so it is a lot |
521 | * faster). |
522 | */ |
523 | #ifdef CONFIG_DEBUG_PAGEALLOC |
524 | vunmap_page_range(start, end); |
525 | flush_tlb_kernel_range(start, end); |
526 | #endif |
527 | } |
528 | |
529 | /* |
530 | * lazy_max_pages is the maximum amount of virtual address space we gather up |
531 | * before attempting to purge with a TLB flush. |
532 | * |
533 | * There is a tradeoff here: a larger number will cover more kernel page tables |
534 | * and take slightly longer to purge, but it will linearly reduce the number of |
535 | * global TLB flushes that must be performed. It would seem natural to scale |
536 | * this number up linearly with the number of CPUs (because vmapping activity |
537 | * could also scale linearly with the number of CPUs), however it is likely |
538 | * that in practice, workloads might be constrained in other ways that mean |
539 | * vmap activity will not scale linearly with CPUs. Also, I want to be |
540 | * conservative and not introduce a big latency on huge systems, so go with |
541 | * a less aggressive log scale. It will still be an improvement over the old |
542 | * code, and it will be simple to change the scale factor if we find that it |
543 | * becomes a problem on bigger systems. |
544 | */ |
545 | static unsigned long lazy_max_pages(void) |
546 | { |
547 | unsigned int log; |
548 | |
549 | log = fls(num_online_cpus()); |
550 | |
551 | return log * (32UL * 1024 * 1024 / PAGE_SIZE); |
552 | } |
553 | |
554 | static atomic_t vmap_lazy_nr = ATOMIC_INIT(0); |
555 | |
556 | /* for per-CPU blocks */ |
557 | static void purge_fragmented_blocks_allcpus(void); |
558 | |
559 | /* |
560 | * called before a call to iounmap() if the caller wants vm_area_struct's |
561 | * immediately freed. |
562 | */ |
563 | void set_iounmap_nonlazy(void) |
564 | { |
565 | atomic_set(&vmap_lazy_nr, lazy_max_pages()+1); |
566 | } |
567 | |
568 | /* |
569 | * Purges all lazily-freed vmap areas. |
570 | * |
571 | * If sync is 0 then don't purge if there is already a purge in progress. |
572 | * If force_flush is 1, then flush kernel TLBs between *start and *end even |
573 | * if we found no lazy vmap areas to unmap (callers can use this to optimise |
574 | * their own TLB flushing). |
575 | * Returns with *start = min(*start, lowest purged address) |
576 | * *end = max(*end, highest purged address) |
577 | */ |
578 | static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end, |
579 | int sync, int force_flush) |
580 | { |
581 | static DEFINE_SPINLOCK(purge_lock); |
582 | LIST_HEAD(valist); |
583 | struct vmap_area *va; |
584 | struct vmap_area *n_va; |
585 | int nr = 0; |
586 | |
587 | /* |
588 | * If sync is 0 but force_flush is 1, we'll go sync anyway but callers |
589 | * should not expect such behaviour. This just simplifies locking for |
590 | * the case that isn't actually used at the moment anyway. |
591 | */ |
592 | if (!sync && !force_flush) { |
593 | if (!spin_trylock(&purge_lock)) |
594 | return; |
595 | } else |
596 | spin_lock(&purge_lock); |
597 | |
598 | if (sync) |
599 | purge_fragmented_blocks_allcpus(); |
600 | |
601 | rcu_read_lock(); |
602 | list_for_each_entry_rcu(va, &vmap_area_list, list) { |
603 | if (va->flags & VM_LAZY_FREE) { |
604 | if (va->va_start < *start) |
605 | *start = va->va_start; |
606 | if (va->va_end > *end) |
607 | *end = va->va_end; |
608 | nr += (va->va_end - va->va_start) >> PAGE_SHIFT; |
609 | list_add_tail(&va->purge_list, &valist); |
610 | va->flags |= VM_LAZY_FREEING; |
611 | va->flags &= ~VM_LAZY_FREE; |
612 | } |
613 | } |
614 | rcu_read_unlock(); |
615 | |
616 | if (nr) |
617 | atomic_sub(nr, &vmap_lazy_nr); |
618 | |
619 | if (nr || force_flush) |
620 | flush_tlb_kernel_range(*start, *end); |
621 | |
622 | if (nr) { |
623 | spin_lock(&vmap_area_lock); |
624 | list_for_each_entry_safe(va, n_va, &valist, purge_list) |
625 | __free_vmap_area(va); |
626 | spin_unlock(&vmap_area_lock); |
627 | } |
628 | spin_unlock(&purge_lock); |
629 | } |
630 | |
631 | /* |
632 | * Kick off a purge of the outstanding lazy areas. Don't bother if somebody |
633 | * is already purging. |
634 | */ |
635 | static void try_purge_vmap_area_lazy(void) |
636 | { |
637 | unsigned long start = ULONG_MAX, end = 0; |
638 | |
639 | __purge_vmap_area_lazy(&start, &end, 0, 0); |
640 | } |
641 | |
642 | /* |
643 | * Kick off a purge of the outstanding lazy areas. |
644 | */ |
645 | static void purge_vmap_area_lazy(void) |
646 | { |
647 | unsigned long start = ULONG_MAX, end = 0; |
648 | |
649 | __purge_vmap_area_lazy(&start, &end, 1, 0); |
650 | } |
651 | |
652 | /* |
653 | * Free a vmap area, caller ensuring that the area has been unmapped |
654 | * and flush_cache_vunmap had been called for the correct range |
655 | * previously. |
656 | */ |
657 | static void free_vmap_area_noflush(struct vmap_area *va) |
658 | { |
659 | va->flags |= VM_LAZY_FREE; |
660 | atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr); |
661 | if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages())) |
662 | try_purge_vmap_area_lazy(); |
663 | } |
664 | |
665 | /* |
666 | * Free and unmap a vmap area, caller ensuring flush_cache_vunmap had been |
667 | * called for the correct range previously. |
668 | */ |
669 | static void free_unmap_vmap_area_noflush(struct vmap_area *va) |
670 | { |
671 | unmap_vmap_area(va); |
672 | free_vmap_area_noflush(va); |
673 | } |
674 | |
675 | /* |
676 | * Free and unmap a vmap area |
677 | */ |
678 | static void free_unmap_vmap_area(struct vmap_area *va) |
679 | { |
680 | flush_cache_vunmap(va->va_start, va->va_end); |
681 | free_unmap_vmap_area_noflush(va); |
682 | } |
683 | |
684 | static struct vmap_area *find_vmap_area(unsigned long addr) |
685 | { |
686 | struct vmap_area *va; |
687 | |
688 | spin_lock(&vmap_area_lock); |
689 | va = __find_vmap_area(addr); |
690 | spin_unlock(&vmap_area_lock); |
691 | |
692 | return va; |
693 | } |
694 | |
695 | static void free_unmap_vmap_area_addr(unsigned long addr) |
696 | { |
697 | struct vmap_area *va; |
698 | |
699 | va = find_vmap_area(addr); |
700 | BUG_ON(!va); |
701 | free_unmap_vmap_area(va); |
702 | } |
703 | |
704 | |
705 | /*** Per cpu kva allocator ***/ |
706 | |
707 | /* |
708 | * vmap space is limited especially on 32 bit architectures. Ensure there is |
709 | * room for at least 16 percpu vmap blocks per CPU. |
710 | */ |
711 | /* |
712 | * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able |
713 | * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess |
714 | * instead (we just need a rough idea) |
715 | */ |
716 | #if BITS_PER_LONG == 32 |
717 | #define VMALLOC_SPACE (128UL*1024*1024) |
718 | #else |
719 | #define VMALLOC_SPACE (128UL*1024*1024*1024) |
720 | #endif |
721 | |
722 | #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE) |
723 | #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */ |
724 | #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */ |
725 | #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2) |
726 | #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */ |
727 | #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */ |
728 | #define VMAP_BBMAP_BITS \ |
729 | VMAP_MIN(VMAP_BBMAP_BITS_MAX, \ |
730 | VMAP_MAX(VMAP_BBMAP_BITS_MIN, \ |
731 | VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16)) |
732 | |
733 | #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE) |
734 | |
735 | static bool vmap_initialized __read_mostly = false; |
736 | |
737 | struct vmap_block_queue { |
738 | spinlock_t lock; |
739 | struct list_head free; |
740 | }; |
741 | |
742 | struct vmap_block { |
743 | spinlock_t lock; |
744 | struct vmap_area *va; |
745 | struct vmap_block_queue *vbq; |
746 | unsigned long free, dirty; |
747 | DECLARE_BITMAP(alloc_map, VMAP_BBMAP_BITS); |
748 | DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS); |
749 | struct list_head free_list; |
750 | struct rcu_head rcu_head; |
751 | struct list_head purge; |
752 | }; |
753 | |
754 | /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */ |
755 | static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue); |
756 | |
757 | /* |
758 | * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block |
759 | * in the free path. Could get rid of this if we change the API to return a |
760 | * "cookie" from alloc, to be passed to free. But no big deal yet. |
761 | */ |
762 | static DEFINE_SPINLOCK(vmap_block_tree_lock); |
763 | static RADIX_TREE(vmap_block_tree, GFP_ATOMIC); |
764 | |
765 | /* |
766 | * We should probably have a fallback mechanism to allocate virtual memory |
767 | * out of partially filled vmap blocks. However vmap block sizing should be |
768 | * fairly reasonable according to the vmalloc size, so it shouldn't be a |
769 | * big problem. |
770 | */ |
771 | |
772 | static unsigned long addr_to_vb_idx(unsigned long addr) |
773 | { |
774 | addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1); |
775 | addr /= VMAP_BLOCK_SIZE; |
776 | return addr; |
777 | } |
778 | |
779 | static struct vmap_block *new_vmap_block(gfp_t gfp_mask) |
780 | { |
781 | struct vmap_block_queue *vbq; |
782 | struct vmap_block *vb; |
783 | struct vmap_area *va; |
784 | unsigned long vb_idx; |
785 | int node, err; |
786 | |
787 | node = numa_node_id(); |
788 | |
789 | vb = kmalloc_node(sizeof(struct vmap_block), |
790 | gfp_mask & GFP_RECLAIM_MASK, node); |
791 | if (unlikely(!vb)) |
792 | return ERR_PTR(-ENOMEM); |
793 | |
794 | va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE, |
795 | VMALLOC_START, VMALLOC_END, |
796 | node, gfp_mask); |
797 | if (IS_ERR(va)) { |
798 | kfree(vb); |
799 | return ERR_CAST(va); |
800 | } |
801 | |
802 | err = radix_tree_preload(gfp_mask); |
803 | if (unlikely(err)) { |
804 | kfree(vb); |
805 | free_vmap_area(va); |
806 | return ERR_PTR(err); |
807 | } |
808 | |
809 | spin_lock_init(&vb->lock); |
810 | vb->va = va; |
811 | vb->free = VMAP_BBMAP_BITS; |
812 | vb->dirty = 0; |
813 | bitmap_zero(vb->alloc_map, VMAP_BBMAP_BITS); |
814 | bitmap_zero(vb->dirty_map, VMAP_BBMAP_BITS); |
815 | INIT_LIST_HEAD(&vb->free_list); |
816 | |
817 | vb_idx = addr_to_vb_idx(va->va_start); |
818 | spin_lock(&vmap_block_tree_lock); |
819 | err = radix_tree_insert(&vmap_block_tree, vb_idx, vb); |
820 | spin_unlock(&vmap_block_tree_lock); |
821 | BUG_ON(err); |
822 | radix_tree_preload_end(); |
823 | |
824 | vbq = &get_cpu_var(vmap_block_queue); |
825 | vb->vbq = vbq; |
826 | spin_lock(&vbq->lock); |
827 | list_add_rcu(&vb->free_list, &vbq->free); |
828 | spin_unlock(&vbq->lock); |
829 | put_cpu_var(vmap_block_queue); |
830 | |
831 | return vb; |
832 | } |
833 | |
834 | static void free_vmap_block(struct vmap_block *vb) |
835 | { |
836 | struct vmap_block *tmp; |
837 | unsigned long vb_idx; |
838 | |
839 | vb_idx = addr_to_vb_idx(vb->va->va_start); |
840 | spin_lock(&vmap_block_tree_lock); |
841 | tmp = radix_tree_delete(&vmap_block_tree, vb_idx); |
842 | spin_unlock(&vmap_block_tree_lock); |
843 | BUG_ON(tmp != vb); |
844 | |
845 | free_vmap_area_noflush(vb->va); |
846 | kfree_rcu(vb, rcu_head); |
847 | } |
848 | |
849 | static void purge_fragmented_blocks(int cpu) |
850 | { |
851 | LIST_HEAD(purge); |
852 | struct vmap_block *vb; |
853 | struct vmap_block *n_vb; |
854 | struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu); |
855 | |
856 | rcu_read_lock(); |
857 | list_for_each_entry_rcu(vb, &vbq->free, free_list) { |
858 | |
859 | if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS)) |
860 | continue; |
861 | |
862 | spin_lock(&vb->lock); |
863 | if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) { |
864 | vb->free = 0; /* prevent further allocs after releasing lock */ |
865 | vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */ |
866 | bitmap_fill(vb->alloc_map, VMAP_BBMAP_BITS); |
867 | bitmap_fill(vb->dirty_map, VMAP_BBMAP_BITS); |
868 | spin_lock(&vbq->lock); |
869 | list_del_rcu(&vb->free_list); |
870 | spin_unlock(&vbq->lock); |
871 | spin_unlock(&vb->lock); |
872 | list_add_tail(&vb->purge, &purge); |
873 | } else |
874 | spin_unlock(&vb->lock); |
875 | } |
876 | rcu_read_unlock(); |
877 | |
878 | list_for_each_entry_safe(vb, n_vb, &purge, purge) { |
879 | list_del(&vb->purge); |
880 | free_vmap_block(vb); |
881 | } |
882 | } |
883 | |
884 | static void purge_fragmented_blocks_thiscpu(void) |
885 | { |
886 | purge_fragmented_blocks(smp_processor_id()); |
887 | } |
888 | |
889 | static void purge_fragmented_blocks_allcpus(void) |
890 | { |
891 | int cpu; |
892 | |
893 | for_each_possible_cpu(cpu) |
894 | purge_fragmented_blocks(cpu); |
895 | } |
896 | |
897 | static void *vb_alloc(unsigned long size, gfp_t gfp_mask) |
898 | { |
899 | struct vmap_block_queue *vbq; |
900 | struct vmap_block *vb; |
901 | unsigned long addr = 0; |
902 | unsigned int order; |
903 | int purge = 0; |
904 | |
905 | BUG_ON(size & ~PAGE_MASK); |
906 | BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); |
907 | order = get_order(size); |
908 | |
909 | again: |
910 | rcu_read_lock(); |
911 | vbq = &get_cpu_var(vmap_block_queue); |
912 | list_for_each_entry_rcu(vb, &vbq->free, free_list) { |
913 | int i; |
914 | |
915 | spin_lock(&vb->lock); |
916 | if (vb->free < 1UL << order) |
917 | goto next; |
918 | |
919 | i = bitmap_find_free_region(vb->alloc_map, |
920 | VMAP_BBMAP_BITS, order); |
921 | |
922 | if (i < 0) { |
923 | if (vb->free + vb->dirty == VMAP_BBMAP_BITS) { |
924 | /* fragmented and no outstanding allocations */ |
925 | BUG_ON(vb->dirty != VMAP_BBMAP_BITS); |
926 | purge = 1; |
927 | } |
928 | goto next; |
929 | } |
930 | addr = vb->va->va_start + (i << PAGE_SHIFT); |
931 | BUG_ON(addr_to_vb_idx(addr) != |
932 | addr_to_vb_idx(vb->va->va_start)); |
933 | vb->free -= 1UL << order; |
934 | if (vb->free == 0) { |
935 | spin_lock(&vbq->lock); |
936 | list_del_rcu(&vb->free_list); |
937 | spin_unlock(&vbq->lock); |
938 | } |
939 | spin_unlock(&vb->lock); |
940 | break; |
941 | next: |
942 | spin_unlock(&vb->lock); |
943 | } |
944 | |
945 | if (purge) |
946 | purge_fragmented_blocks_thiscpu(); |
947 | |
948 | put_cpu_var(vmap_block_queue); |
949 | rcu_read_unlock(); |
950 | |
951 | if (!addr) { |
952 | vb = new_vmap_block(gfp_mask); |
953 | if (IS_ERR(vb)) |
954 | return vb; |
955 | goto again; |
956 | } |
957 | |
958 | return (void *)addr; |
959 | } |
960 | |
961 | static void vb_free(const void *addr, unsigned long size) |
962 | { |
963 | unsigned long offset; |
964 | unsigned long vb_idx; |
965 | unsigned int order; |
966 | struct vmap_block *vb; |
967 | |
968 | BUG_ON(size & ~PAGE_MASK); |
969 | BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); |
970 | |
971 | flush_cache_vunmap((unsigned long)addr, (unsigned long)addr + size); |
972 | |
973 | order = get_order(size); |
974 | |
975 | offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1); |
976 | |
977 | vb_idx = addr_to_vb_idx((unsigned long)addr); |
978 | rcu_read_lock(); |
979 | vb = radix_tree_lookup(&vmap_block_tree, vb_idx); |
980 | rcu_read_unlock(); |
981 | BUG_ON(!vb); |
982 | |
983 | vunmap_page_range((unsigned long)addr, (unsigned long)addr + size); |
984 | |
985 | spin_lock(&vb->lock); |
986 | BUG_ON(bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order)); |
987 | |
988 | vb->dirty += 1UL << order; |
989 | if (vb->dirty == VMAP_BBMAP_BITS) { |
990 | BUG_ON(vb->free); |
991 | spin_unlock(&vb->lock); |
992 | free_vmap_block(vb); |
993 | } else |
994 | spin_unlock(&vb->lock); |
995 | } |
996 | |
997 | /** |
998 | * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer |
999 | * |
1000 | * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily |
1001 | * to amortize TLB flushing overheads. What this means is that any page you |
1002 | * have now, may, in a former life, have been mapped into kernel virtual |
1003 | * address by the vmap layer and so there might be some CPUs with TLB entries |
1004 | * still referencing that page (additional to the regular 1:1 kernel mapping). |
1005 | * |
1006 | * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can |
1007 | * be sure that none of the pages we have control over will have any aliases |
1008 | * from the vmap layer. |
1009 | */ |
1010 | void vm_unmap_aliases(void) |
1011 | { |
1012 | unsigned long start = ULONG_MAX, end = 0; |
1013 | int cpu; |
1014 | int flush = 0; |
1015 | |
1016 | if (unlikely(!vmap_initialized)) |
1017 | return; |
1018 | |
1019 | for_each_possible_cpu(cpu) { |
1020 | struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu); |
1021 | struct vmap_block *vb; |
1022 | |
1023 | rcu_read_lock(); |
1024 | list_for_each_entry_rcu(vb, &vbq->free, free_list) { |
1025 | int i; |
1026 | |
1027 | spin_lock(&vb->lock); |
1028 | i = find_first_bit(vb->dirty_map, VMAP_BBMAP_BITS); |
1029 | while (i < VMAP_BBMAP_BITS) { |
1030 | unsigned long s, e; |
1031 | int j; |
1032 | j = find_next_zero_bit(vb->dirty_map, |
1033 | VMAP_BBMAP_BITS, i); |
1034 | |
1035 | s = vb->va->va_start + (i << PAGE_SHIFT); |
1036 | e = vb->va->va_start + (j << PAGE_SHIFT); |
1037 | flush = 1; |
1038 | |
1039 | if (s < start) |
1040 | start = s; |
1041 | if (e > end) |
1042 | end = e; |
1043 | |
1044 | i = j; |
1045 | i = find_next_bit(vb->dirty_map, |
1046 | VMAP_BBMAP_BITS, i); |
1047 | } |
1048 | spin_unlock(&vb->lock); |
1049 | } |
1050 | rcu_read_unlock(); |
1051 | } |
1052 | |
1053 | __purge_vmap_area_lazy(&start, &end, 1, flush); |
1054 | } |
1055 | EXPORT_SYMBOL_GPL(vm_unmap_aliases); |
1056 | |
1057 | /** |
1058 | * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram |
1059 | * @mem: the pointer returned by vm_map_ram |
1060 | * @count: the count passed to that vm_map_ram call (cannot unmap partial) |
1061 | */ |
1062 | void vm_unmap_ram(const void *mem, unsigned int count) |
1063 | { |
1064 | unsigned long size = count << PAGE_SHIFT; |
1065 | unsigned long addr = (unsigned long)mem; |
1066 | |
1067 | BUG_ON(!addr); |
1068 | BUG_ON(addr < VMALLOC_START); |
1069 | BUG_ON(addr > VMALLOC_END); |
1070 | BUG_ON(addr & (PAGE_SIZE-1)); |
1071 | |
1072 | debug_check_no_locks_freed(mem, size); |
1073 | vmap_debug_free_range(addr, addr+size); |
1074 | |
1075 | if (likely(count <= VMAP_MAX_ALLOC)) |
1076 | vb_free(mem, size); |
1077 | else |
1078 | free_unmap_vmap_area_addr(addr); |
1079 | } |
1080 | EXPORT_SYMBOL(vm_unmap_ram); |
1081 | |
1082 | /** |
1083 | * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space) |
1084 | * @pages: an array of pointers to the pages to be mapped |
1085 | * @count: number of pages |
1086 | * @node: prefer to allocate data structures on this node |
1087 | * @prot: memory protection to use. PAGE_KERNEL for regular RAM |
1088 | * |
1089 | * Returns: a pointer to the address that has been mapped, or %NULL on failure |
1090 | */ |
1091 | void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot) |
1092 | { |
1093 | unsigned long size = count << PAGE_SHIFT; |
1094 | unsigned long addr; |
1095 | void *mem; |
1096 | |
1097 | if (likely(count <= VMAP_MAX_ALLOC)) { |
1098 | mem = vb_alloc(size, GFP_KERNEL); |
1099 | if (IS_ERR(mem)) |
1100 | return NULL; |
1101 | addr = (unsigned long)mem; |
1102 | } else { |
1103 | struct vmap_area *va; |
1104 | va = alloc_vmap_area(size, PAGE_SIZE, |
1105 | VMALLOC_START, VMALLOC_END, node, GFP_KERNEL); |
1106 | if (IS_ERR(va)) |
1107 | return NULL; |
1108 | |
1109 | addr = va->va_start; |
1110 | mem = (void *)addr; |
1111 | } |
1112 | if (vmap_page_range(addr, addr + size, prot, pages) < 0) { |
1113 | vm_unmap_ram(mem, count); |
1114 | return NULL; |
1115 | } |
1116 | return mem; |
1117 | } |
1118 | EXPORT_SYMBOL(vm_map_ram); |
1119 | |
1120 | /** |
1121 | * vm_area_register_early - register vmap area early during boot |
1122 | * @vm: vm_struct to register |
1123 | * @align: requested alignment |
1124 | * |
1125 | * This function is used to register kernel vm area before |
1126 | * vmalloc_init() is called. @vm->size and @vm->flags should contain |
1127 | * proper values on entry and other fields should be zero. On return, |
1128 | * vm->addr contains the allocated address. |
1129 | * |
1130 | * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING. |
1131 | */ |
1132 | void __init vm_area_register_early(struct vm_struct *vm, size_t align) |
1133 | { |
1134 | static size_t vm_init_off __initdata; |
1135 | unsigned long addr; |
1136 | |
1137 | addr = ALIGN(VMALLOC_START + vm_init_off, align); |
1138 | vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START; |
1139 | |
1140 | vm->addr = (void *)addr; |
1141 | |
1142 | vm->next = vmlist; |
1143 | vmlist = vm; |
1144 | } |
1145 | |
1146 | void __init vmalloc_init(void) |
1147 | { |
1148 | struct vmap_area *va; |
1149 | struct vm_struct *tmp; |
1150 | int i; |
1151 | |
1152 | for_each_possible_cpu(i) { |
1153 | struct vmap_block_queue *vbq; |
1154 | |
1155 | vbq = &per_cpu(vmap_block_queue, i); |
1156 | spin_lock_init(&vbq->lock); |
1157 | INIT_LIST_HEAD(&vbq->free); |
1158 | } |
1159 | |
1160 | /* Import existing vmlist entries. */ |
1161 | for (tmp = vmlist; tmp; tmp = tmp->next) { |
1162 | va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT); |
1163 | va->flags = tmp->flags | VM_VM_AREA; |
1164 | va->va_start = (unsigned long)tmp->addr; |
1165 | va->va_end = va->va_start + tmp->size; |
1166 | __insert_vmap_area(va); |
1167 | } |
1168 | |
1169 | vmap_area_pcpu_hole = VMALLOC_END; |
1170 | |
1171 | vmap_initialized = true; |
1172 | } |
1173 | |
1174 | /** |
1175 | * map_kernel_range_noflush - map kernel VM area with the specified pages |
1176 | * @addr: start of the VM area to map |
1177 | * @size: size of the VM area to map |
1178 | * @prot: page protection flags to use |
1179 | * @pages: pages to map |
1180 | * |
1181 | * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size |
1182 | * specify should have been allocated using get_vm_area() and its |
1183 | * friends. |
1184 | * |
1185 | * NOTE: |
1186 | * This function does NOT do any cache flushing. The caller is |
1187 | * responsible for calling flush_cache_vmap() on to-be-mapped areas |
1188 | * before calling this function. |
1189 | * |
1190 | * RETURNS: |
1191 | * The number of pages mapped on success, -errno on failure. |
1192 | */ |
1193 | int map_kernel_range_noflush(unsigned long addr, unsigned long size, |
1194 | pgprot_t prot, struct page **pages) |
1195 | { |
1196 | return vmap_page_range_noflush(addr, addr + size, prot, pages); |
1197 | } |
1198 | |
1199 | /** |
1200 | * unmap_kernel_range_noflush - unmap kernel VM area |
1201 | * @addr: start of the VM area to unmap |
1202 | * @size: size of the VM area to unmap |
1203 | * |
1204 | * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size |
1205 | * specify should have been allocated using get_vm_area() and its |
1206 | * friends. |
1207 | * |
1208 | * NOTE: |
1209 | * This function does NOT do any cache flushing. The caller is |
1210 | * responsible for calling flush_cache_vunmap() on to-be-mapped areas |
1211 | * before calling this function and flush_tlb_kernel_range() after. |
1212 | */ |
1213 | void unmap_kernel_range_noflush(unsigned long addr, unsigned long size) |
1214 | { |
1215 | vunmap_page_range(addr, addr + size); |
1216 | } |
1217 | EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush); |
1218 | |
1219 | /** |
1220 | * unmap_kernel_range - unmap kernel VM area and flush cache and TLB |
1221 | * @addr: start of the VM area to unmap |
1222 | * @size: size of the VM area to unmap |
1223 | * |
1224 | * Similar to unmap_kernel_range_noflush() but flushes vcache before |
1225 | * the unmapping and tlb after. |
1226 | */ |
1227 | void unmap_kernel_range(unsigned long addr, unsigned long size) |
1228 | { |
1229 | unsigned long end = addr + size; |
1230 | |
1231 | flush_cache_vunmap(addr, end); |
1232 | vunmap_page_range(addr, end); |
1233 | flush_tlb_kernel_range(addr, end); |
1234 | } |
1235 | |
1236 | int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages) |
1237 | { |
1238 | unsigned long addr = (unsigned long)area->addr; |
1239 | unsigned long end = addr + area->size - PAGE_SIZE; |
1240 | int err; |
1241 | |
1242 | err = vmap_page_range(addr, end, prot, *pages); |
1243 | if (err > 0) { |
1244 | *pages += err; |
1245 | err = 0; |
1246 | } |
1247 | |
1248 | return err; |
1249 | } |
1250 | EXPORT_SYMBOL_GPL(map_vm_area); |
1251 | |
1252 | /*** Old vmalloc interfaces ***/ |
1253 | DEFINE_RWLOCK(vmlist_lock); |
1254 | struct vm_struct *vmlist; |
1255 | |
1256 | static void insert_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, |
1257 | unsigned long flags, void *caller) |
1258 | { |
1259 | struct vm_struct *tmp, **p; |
1260 | |
1261 | vm->flags = flags; |
1262 | vm->addr = (void *)va->va_start; |
1263 | vm->size = va->va_end - va->va_start; |
1264 | vm->caller = caller; |
1265 | va->private = vm; |
1266 | va->flags |= VM_VM_AREA; |
1267 | |
1268 | write_lock(&vmlist_lock); |
1269 | for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) { |
1270 | if (tmp->addr >= vm->addr) |
1271 | break; |
1272 | } |
1273 | vm->next = *p; |
1274 | *p = vm; |
1275 | write_unlock(&vmlist_lock); |
1276 | } |
1277 | |
1278 | static struct vm_struct *__get_vm_area_node(unsigned long size, |
1279 | unsigned long align, unsigned long flags, unsigned long start, |
1280 | unsigned long end, int node, gfp_t gfp_mask, void *caller) |
1281 | { |
1282 | static struct vmap_area *va; |
1283 | struct vm_struct *area; |
1284 | |
1285 | BUG_ON(in_interrupt()); |
1286 | if (flags & VM_IOREMAP) { |
1287 | int bit = fls(size); |
1288 | |
1289 | if (bit > IOREMAP_MAX_ORDER) |
1290 | bit = IOREMAP_MAX_ORDER; |
1291 | else if (bit < PAGE_SHIFT) |
1292 | bit = PAGE_SHIFT; |
1293 | |
1294 | align = 1ul << bit; |
1295 | } |
1296 | |
1297 | size = PAGE_ALIGN(size); |
1298 | if (unlikely(!size)) |
1299 | return NULL; |
1300 | |
1301 | area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node); |
1302 | if (unlikely(!area)) |
1303 | return NULL; |
1304 | |
1305 | /* |
1306 | * We always allocate a guard page. |
1307 | */ |
1308 | size += PAGE_SIZE; |
1309 | |
1310 | va = alloc_vmap_area(size, align, start, end, node, gfp_mask); |
1311 | if (IS_ERR(va)) { |
1312 | kfree(area); |
1313 | return NULL; |
1314 | } |
1315 | |
1316 | insert_vmalloc_vm(area, va, flags, caller); |
1317 | return area; |
1318 | } |
1319 | |
1320 | struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, |
1321 | unsigned long start, unsigned long end) |
1322 | { |
1323 | return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL, |
1324 | __builtin_return_address(0)); |
1325 | } |
1326 | EXPORT_SYMBOL_GPL(__get_vm_area); |
1327 | |
1328 | struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags, |
1329 | unsigned long start, unsigned long end, |
1330 | void *caller) |
1331 | { |
1332 | return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL, |
1333 | caller); |
1334 | } |
1335 | |
1336 | /** |
1337 | * get_vm_area - reserve a contiguous kernel virtual area |
1338 | * @size: size of the area |
1339 | * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC |
1340 | * |
1341 | * Search an area of @size in the kernel virtual mapping area, |
1342 | * and reserved it for out purposes. Returns the area descriptor |
1343 | * on success or %NULL on failure. |
1344 | */ |
1345 | struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) |
1346 | { |
1347 | return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END, |
1348 | -1, GFP_KERNEL, __builtin_return_address(0)); |
1349 | } |
1350 | |
1351 | struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags, |
1352 | void *caller) |
1353 | { |
1354 | return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END, |
1355 | -1, GFP_KERNEL, caller); |
1356 | } |
1357 | |
1358 | static struct vm_struct *find_vm_area(const void *addr) |
1359 | { |
1360 | struct vmap_area *va; |
1361 | |
1362 | va = find_vmap_area((unsigned long)addr); |
1363 | if (va && va->flags & VM_VM_AREA) |
1364 | return va->private; |
1365 | |
1366 | return NULL; |
1367 | } |
1368 | |
1369 | /** |
1370 | * remove_vm_area - find and remove a continuous kernel virtual area |
1371 | * @addr: base address |
1372 | * |
1373 | * Search for the kernel VM area starting at @addr, and remove it. |
1374 | * This function returns the found VM area, but using it is NOT safe |
1375 | * on SMP machines, except for its size or flags. |
1376 | */ |
1377 | struct vm_struct *remove_vm_area(const void *addr) |
1378 | { |
1379 | struct vmap_area *va; |
1380 | |
1381 | va = find_vmap_area((unsigned long)addr); |
1382 | if (va && va->flags & VM_VM_AREA) { |
1383 | struct vm_struct *vm = va->private; |
1384 | struct vm_struct *tmp, **p; |
1385 | /* |
1386 | * remove from list and disallow access to this vm_struct |
1387 | * before unmap. (address range confliction is maintained by |
1388 | * vmap.) |
1389 | */ |
1390 | write_lock(&vmlist_lock); |
1391 | for (p = &vmlist; (tmp = *p) != vm; p = &tmp->next) |
1392 | ; |
1393 | *p = tmp->next; |
1394 | write_unlock(&vmlist_lock); |
1395 | |
1396 | vmap_debug_free_range(va->va_start, va->va_end); |
1397 | free_unmap_vmap_area(va); |
1398 | vm->size -= PAGE_SIZE; |
1399 | |
1400 | return vm; |
1401 | } |
1402 | return NULL; |
1403 | } |
1404 | |
1405 | static void __vunmap(const void *addr, int deallocate_pages) |
1406 | { |
1407 | struct vm_struct *area; |
1408 | |
1409 | if (!addr) |
1410 | return; |
1411 | |
1412 | if ((PAGE_SIZE-1) & (unsigned long)addr) { |
1413 | WARN(1, KERN_ERR "Trying to vfree() bad address (%p)\n", addr); |
1414 | return; |
1415 | } |
1416 | |
1417 | area = remove_vm_area(addr); |
1418 | if (unlikely(!area)) { |
1419 | WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", |
1420 | addr); |
1421 | return; |
1422 | } |
1423 | |
1424 | debug_check_no_locks_freed(addr, area->size); |
1425 | debug_check_no_obj_freed(addr, area->size); |
1426 | |
1427 | if (deallocate_pages) { |
1428 | int i; |
1429 | |
1430 | for (i = 0; i < area->nr_pages; i++) { |
1431 | struct page *page = area->pages[i]; |
1432 | |
1433 | BUG_ON(!page); |
1434 | __free_page(page); |
1435 | } |
1436 | |
1437 | if (area->flags & VM_VPAGES) |
1438 | vfree(area->pages); |
1439 | else |
1440 | kfree(area->pages); |
1441 | } |
1442 | |
1443 | kfree(area); |
1444 | return; |
1445 | } |
1446 | |
1447 | /** |
1448 | * vfree - release memory allocated by vmalloc() |
1449 | * @addr: memory base address |
1450 | * |
1451 | * Free the virtually continuous memory area starting at @addr, as |
1452 | * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is |
1453 | * NULL, no operation is performed. |
1454 | * |
1455 | * Must not be called in interrupt context. |
1456 | */ |
1457 | void vfree(const void *addr) |
1458 | { |
1459 | BUG_ON(in_interrupt()); |
1460 | |
1461 | kmemleak_free(addr); |
1462 | |
1463 | __vunmap(addr, 1); |
1464 | } |
1465 | EXPORT_SYMBOL(vfree); |
1466 | |
1467 | /** |
1468 | * vunmap - release virtual mapping obtained by vmap() |
1469 | * @addr: memory base address |
1470 | * |
1471 | * Free the virtually contiguous memory area starting at @addr, |
1472 | * which was created from the page array passed to vmap(). |
1473 | * |
1474 | * Must not be called in interrupt context. |
1475 | */ |
1476 | void vunmap(const void *addr) |
1477 | { |
1478 | BUG_ON(in_interrupt()); |
1479 | might_sleep(); |
1480 | __vunmap(addr, 0); |
1481 | } |
1482 | EXPORT_SYMBOL(vunmap); |
1483 | |
1484 | /** |
1485 | * vmap - map an array of pages into virtually contiguous space |
1486 | * @pages: array of page pointers |
1487 | * @count: number of pages to map |
1488 | * @flags: vm_area->flags |
1489 | * @prot: page protection for the mapping |
1490 | * |
1491 | * Maps @count pages from @pages into contiguous kernel virtual |
1492 | * space. |
1493 | */ |
1494 | void *vmap(struct page **pages, unsigned int count, |
1495 | unsigned long flags, pgprot_t prot) |
1496 | { |
1497 | struct vm_struct *area; |
1498 | |
1499 | might_sleep(); |
1500 | |
1501 | if (count > totalram_pages) |
1502 | return NULL; |
1503 | |
1504 | area = get_vm_area_caller((count << PAGE_SHIFT), flags, |
1505 | __builtin_return_address(0)); |
1506 | if (!area) |
1507 | return NULL; |
1508 | |
1509 | if (map_vm_area(area, prot, &pages)) { |
1510 | vunmap(area->addr); |
1511 | return NULL; |
1512 | } |
1513 | |
1514 | return area->addr; |
1515 | } |
1516 | EXPORT_SYMBOL(vmap); |
1517 | |
1518 | static void *__vmalloc_node(unsigned long size, unsigned long align, |
1519 | gfp_t gfp_mask, pgprot_t prot, |
1520 | int node, void *caller); |
1521 | static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, |
1522 | pgprot_t prot, int node, void *caller) |
1523 | { |
1524 | const int order = 0; |
1525 | struct page **pages; |
1526 | unsigned int nr_pages, array_size, i; |
1527 | gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO; |
1528 | |
1529 | nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT; |
1530 | array_size = (nr_pages * sizeof(struct page *)); |
1531 | |
1532 | area->nr_pages = nr_pages; |
1533 | /* Please note that the recursion is strictly bounded. */ |
1534 | if (array_size > PAGE_SIZE) { |
1535 | pages = __vmalloc_node(array_size, 1, nested_gfp|__GFP_HIGHMEM, |
1536 | PAGE_KERNEL, node, caller); |
1537 | area->flags |= VM_VPAGES; |
1538 | } else { |
1539 | pages = kmalloc_node(array_size, nested_gfp, node); |
1540 | } |
1541 | area->pages = pages; |
1542 | area->caller = caller; |
1543 | if (!area->pages) { |
1544 | remove_vm_area(area->addr); |
1545 | kfree(area); |
1546 | return NULL; |
1547 | } |
1548 | |
1549 | for (i = 0; i < area->nr_pages; i++) { |
1550 | struct page *page; |
1551 | gfp_t tmp_mask = gfp_mask | __GFP_NOWARN; |
1552 | |
1553 | if (node < 0) |
1554 | page = alloc_page(tmp_mask); |
1555 | else |
1556 | page = alloc_pages_node(node, tmp_mask, order); |
1557 | |
1558 | if (unlikely(!page)) { |
1559 | /* Successfully allocated i pages, free them in __vunmap() */ |
1560 | area->nr_pages = i; |
1561 | goto fail; |
1562 | } |
1563 | area->pages[i] = page; |
1564 | } |
1565 | |
1566 | if (map_vm_area(area, prot, &pages)) |
1567 | goto fail; |
1568 | return area->addr; |
1569 | |
1570 | fail: |
1571 | warn_alloc_failed(gfp_mask, order, "vmalloc: allocation failure, " |
1572 | "allocated %ld of %ld bytes\n", |
1573 | (area->nr_pages*PAGE_SIZE), area->size); |
1574 | vfree(area->addr); |
1575 | return NULL; |
1576 | } |
1577 | |
1578 | /** |
1579 | * __vmalloc_node_range - allocate virtually contiguous memory |
1580 | * @size: allocation size |
1581 | * @align: desired alignment |
1582 | * @start: vm area range start |
1583 | * @end: vm area range end |
1584 | * @gfp_mask: flags for the page level allocator |
1585 | * @prot: protection mask for the allocated pages |
1586 | * @node: node to use for allocation or -1 |
1587 | * @caller: caller's return address |
1588 | * |
1589 | * Allocate enough pages to cover @size from the page level |
1590 | * allocator with @gfp_mask flags. Map them into contiguous |
1591 | * kernel virtual space, using a pagetable protection of @prot. |
1592 | */ |
1593 | void *__vmalloc_node_range(unsigned long size, unsigned long align, |
1594 | unsigned long start, unsigned long end, gfp_t gfp_mask, |
1595 | pgprot_t prot, int node, void *caller) |
1596 | { |
1597 | struct vm_struct *area; |
1598 | void *addr; |
1599 | unsigned long real_size = size; |
1600 | |
1601 | size = PAGE_ALIGN(size); |
1602 | if (!size || (size >> PAGE_SHIFT) > totalram_pages) |
1603 | return NULL; |
1604 | |
1605 | area = __get_vm_area_node(size, align, VM_ALLOC, start, end, node, |
1606 | gfp_mask, caller); |
1607 | |
1608 | if (!area) |
1609 | return NULL; |
1610 | |
1611 | addr = __vmalloc_area_node(area, gfp_mask, prot, node, caller); |
1612 | |
1613 | /* |
1614 | * A ref_count = 3 is needed because the vm_struct and vmap_area |
1615 | * structures allocated in the __get_vm_area_node() function contain |
1616 | * references to the virtual address of the vmalloc'ed block. |
1617 | */ |
1618 | kmemleak_alloc(addr, real_size, 3, gfp_mask); |
1619 | |
1620 | return addr; |
1621 | } |
1622 | |
1623 | /** |
1624 | * __vmalloc_node - allocate virtually contiguous memory |
1625 | * @size: allocation size |
1626 | * @align: desired alignment |
1627 | * @gfp_mask: flags for the page level allocator |
1628 | * @prot: protection mask for the allocated pages |
1629 | * @node: node to use for allocation or -1 |
1630 | * @caller: caller's return address |
1631 | * |
1632 | * Allocate enough pages to cover @size from the page level |
1633 | * allocator with @gfp_mask flags. Map them into contiguous |
1634 | * kernel virtual space, using a pagetable protection of @prot. |
1635 | */ |
1636 | static void *__vmalloc_node(unsigned long size, unsigned long align, |
1637 | gfp_t gfp_mask, pgprot_t prot, |
1638 | int node, void *caller) |
1639 | { |
1640 | return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, |
1641 | gfp_mask, prot, node, caller); |
1642 | } |
1643 | |
1644 | void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) |
1645 | { |
1646 | return __vmalloc_node(size, 1, gfp_mask, prot, -1, |
1647 | __builtin_return_address(0)); |
1648 | } |
1649 | EXPORT_SYMBOL(__vmalloc); |
1650 | |
1651 | static inline void *__vmalloc_node_flags(unsigned long size, |
1652 | int node, gfp_t flags) |
1653 | { |
1654 | return __vmalloc_node(size, 1, flags, PAGE_KERNEL, |
1655 | node, __builtin_return_address(0)); |
1656 | } |
1657 | |
1658 | /** |
1659 | * vmalloc - allocate virtually contiguous memory |
1660 | * @size: allocation size |
1661 | * Allocate enough pages to cover @size from the page level |
1662 | * allocator and map them into contiguous kernel virtual space. |
1663 | * |
1664 | * For tight control over page level allocator and protection flags |
1665 | * use __vmalloc() instead. |
1666 | */ |
1667 | void *vmalloc(unsigned long size) |
1668 | { |
1669 | return __vmalloc_node_flags(size, -1, GFP_KERNEL | __GFP_HIGHMEM); |
1670 | } |
1671 | EXPORT_SYMBOL(vmalloc); |
1672 | |
1673 | /** |
1674 | * vzalloc - allocate virtually contiguous memory with zero fill |
1675 | * @size: allocation size |
1676 | * Allocate enough pages to cover @size from the page level |
1677 | * allocator and map them into contiguous kernel virtual space. |
1678 | * The memory allocated is set to zero. |
1679 | * |
1680 | * For tight control over page level allocator and protection flags |
1681 | * use __vmalloc() instead. |
1682 | */ |
1683 | void *vzalloc(unsigned long size) |
1684 | { |
1685 | return __vmalloc_node_flags(size, -1, |
1686 | GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO); |
1687 | } |
1688 | EXPORT_SYMBOL(vzalloc); |
1689 | |
1690 | /** |
1691 | * vmalloc_user - allocate zeroed virtually contiguous memory for userspace |
1692 | * @size: allocation size |
1693 | * |
1694 | * The resulting memory area is zeroed so it can be mapped to userspace |
1695 | * without leaking data. |
1696 | */ |
1697 | void *vmalloc_user(unsigned long size) |
1698 | { |
1699 | struct vm_struct *area; |
1700 | void *ret; |
1701 | |
1702 | ret = __vmalloc_node(size, SHMLBA, |
1703 | GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO, |
1704 | PAGE_KERNEL, -1, __builtin_return_address(0)); |
1705 | if (ret) { |
1706 | area = find_vm_area(ret); |
1707 | area->flags |= VM_USERMAP; |
1708 | } |
1709 | return ret; |
1710 | } |
1711 | EXPORT_SYMBOL(vmalloc_user); |
1712 | |
1713 | /** |
1714 | * vmalloc_node - allocate memory on a specific node |
1715 | * @size: allocation size |
1716 | * @node: numa node |
1717 | * |
1718 | * Allocate enough pages to cover @size from the page level |
1719 | * allocator and map them into contiguous kernel virtual space. |
1720 | * |
1721 | * For tight control over page level allocator and protection flags |
1722 | * use __vmalloc() instead. |
1723 | */ |
1724 | void *vmalloc_node(unsigned long size, int node) |
1725 | { |
1726 | return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL, |
1727 | node, __builtin_return_address(0)); |
1728 | } |
1729 | EXPORT_SYMBOL(vmalloc_node); |
1730 | |
1731 | /** |
1732 | * vzalloc_node - allocate memory on a specific node with zero fill |
1733 | * @size: allocation size |
1734 | * @node: numa node |
1735 | * |
1736 | * Allocate enough pages to cover @size from the page level |
1737 | * allocator and map them into contiguous kernel virtual space. |
1738 | * The memory allocated is set to zero. |
1739 | * |
1740 | * For tight control over page level allocator and protection flags |
1741 | * use __vmalloc_node() instead. |
1742 | */ |
1743 | void *vzalloc_node(unsigned long size, int node) |
1744 | { |
1745 | return __vmalloc_node_flags(size, node, |
1746 | GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO); |
1747 | } |
1748 | EXPORT_SYMBOL(vzalloc_node); |
1749 | |
1750 | #ifndef PAGE_KERNEL_EXEC |
1751 | # define PAGE_KERNEL_EXEC PAGE_KERNEL |
1752 | #endif |
1753 | |
1754 | /** |
1755 | * vmalloc_exec - allocate virtually contiguous, executable memory |
1756 | * @size: allocation size |
1757 | * |
1758 | * Kernel-internal function to allocate enough pages to cover @size |
1759 | * the page level allocator and map them into contiguous and |
1760 | * executable kernel virtual space. |
1761 | * |
1762 | * For tight control over page level allocator and protection flags |
1763 | * use __vmalloc() instead. |
1764 | */ |
1765 | |
1766 | void *vmalloc_exec(unsigned long size) |
1767 | { |
1768 | return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC, |
1769 | -1, __builtin_return_address(0)); |
1770 | } |
1771 | |
1772 | #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32) |
1773 | #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL |
1774 | #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA) |
1775 | #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL |
1776 | #else |
1777 | #define GFP_VMALLOC32 GFP_KERNEL |
1778 | #endif |
1779 | |
1780 | /** |
1781 | * vmalloc_32 - allocate virtually contiguous memory (32bit addressable) |
1782 | * @size: allocation size |
1783 | * |
1784 | * Allocate enough 32bit PA addressable pages to cover @size from the |
1785 | * page level allocator and map them into contiguous kernel virtual space. |
1786 | */ |
1787 | void *vmalloc_32(unsigned long size) |
1788 | { |
1789 | return __vmalloc_node(size, 1, GFP_VMALLOC32, PAGE_KERNEL, |
1790 | -1, __builtin_return_address(0)); |
1791 | } |
1792 | EXPORT_SYMBOL(vmalloc_32); |
1793 | |
1794 | /** |
1795 | * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory |
1796 | * @size: allocation size |
1797 | * |
1798 | * The resulting memory area is 32bit addressable and zeroed so it can be |
1799 | * mapped to userspace without leaking data. |
1800 | */ |
1801 | void *vmalloc_32_user(unsigned long size) |
1802 | { |
1803 | struct vm_struct *area; |
1804 | void *ret; |
1805 | |
1806 | ret = __vmalloc_node(size, 1, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL, |
1807 | -1, __builtin_return_address(0)); |
1808 | if (ret) { |
1809 | area = find_vm_area(ret); |
1810 | area->flags |= VM_USERMAP; |
1811 | } |
1812 | return ret; |
1813 | } |
1814 | EXPORT_SYMBOL(vmalloc_32_user); |
1815 | |
1816 | /* |
1817 | * small helper routine , copy contents to buf from addr. |
1818 | * If the page is not present, fill zero. |
1819 | */ |
1820 | |
1821 | static int aligned_vread(char *buf, char *addr, unsigned long count) |
1822 | { |
1823 | struct page *p; |
1824 | int copied = 0; |
1825 | |
1826 | while (count) { |
1827 | unsigned long offset, length; |
1828 | |
1829 | offset = (unsigned long)addr & ~PAGE_MASK; |
1830 | length = PAGE_SIZE - offset; |
1831 | if (length > count) |
1832 | length = count; |
1833 | p = vmalloc_to_page(addr); |
1834 | /* |
1835 | * To do safe access to this _mapped_ area, we need |
1836 | * lock. But adding lock here means that we need to add |
1837 | * overhead of vmalloc()/vfree() calles for this _debug_ |
1838 | * interface, rarely used. Instead of that, we'll use |
1839 | * kmap() and get small overhead in this access function. |
1840 | */ |
1841 | if (p) { |
1842 | /* |
1843 | * we can expect USER0 is not used (see vread/vwrite's |
1844 | * function description) |
1845 | */ |
1846 | void *map = kmap_atomic(p, KM_USER0); |
1847 | memcpy(buf, map + offset, length); |
1848 | kunmap_atomic(map, KM_USER0); |
1849 | } else |
1850 | memset(buf, 0, length); |
1851 | |
1852 | addr += length; |
1853 | buf += length; |
1854 | copied += length; |
1855 | count -= length; |
1856 | } |
1857 | return copied; |
1858 | } |
1859 | |
1860 | static int aligned_vwrite(char *buf, char *addr, unsigned long count) |
1861 | { |
1862 | struct page *p; |
1863 | int copied = 0; |
1864 | |
1865 | while (count) { |
1866 | unsigned long offset, length; |
1867 | |
1868 | offset = (unsigned long)addr & ~PAGE_MASK; |
1869 | length = PAGE_SIZE - offset; |
1870 | if (length > count) |
1871 | length = count; |
1872 | p = vmalloc_to_page(addr); |
1873 | /* |
1874 | * To do safe access to this _mapped_ area, we need |
1875 | * lock. But adding lock here means that we need to add |
1876 | * overhead of vmalloc()/vfree() calles for this _debug_ |
1877 | * interface, rarely used. Instead of that, we'll use |
1878 | * kmap() and get small overhead in this access function. |
1879 | */ |
1880 | if (p) { |
1881 | /* |
1882 | * we can expect USER0 is not used (see vread/vwrite's |
1883 | * function description) |
1884 | */ |
1885 | void *map = kmap_atomic(p, KM_USER0); |
1886 | memcpy(map + offset, buf, length); |
1887 | kunmap_atomic(map, KM_USER0); |
1888 | } |
1889 | addr += length; |
1890 | buf += length; |
1891 | copied += length; |
1892 | count -= length; |
1893 | } |
1894 | return copied; |
1895 | } |
1896 | |
1897 | /** |
1898 | * vread() - read vmalloc area in a safe way. |
1899 | * @buf: buffer for reading data |
1900 | * @addr: vm address. |
1901 | * @count: number of bytes to be read. |
1902 | * |
1903 | * Returns # of bytes which addr and buf should be increased. |
1904 | * (same number to @count). Returns 0 if [addr...addr+count) doesn't |
1905 | * includes any intersect with alive vmalloc area. |
1906 | * |
1907 | * This function checks that addr is a valid vmalloc'ed area, and |
1908 | * copy data from that area to a given buffer. If the given memory range |
1909 | * of [addr...addr+count) includes some valid address, data is copied to |
1910 | * proper area of @buf. If there are memory holes, they'll be zero-filled. |
1911 | * IOREMAP area is treated as memory hole and no copy is done. |
1912 | * |
1913 | * If [addr...addr+count) doesn't includes any intersects with alive |
1914 | * vm_struct area, returns 0. |
1915 | * @buf should be kernel's buffer. Because this function uses KM_USER0, |
1916 | * the caller should guarantee KM_USER0 is not used. |
1917 | * |
1918 | * Note: In usual ops, vread() is never necessary because the caller |
1919 | * should know vmalloc() area is valid and can use memcpy(). |
1920 | * This is for routines which have to access vmalloc area without |
1921 | * any informaion, as /dev/kmem. |
1922 | * |
1923 | */ |
1924 | |
1925 | long vread(char *buf, char *addr, unsigned long count) |
1926 | { |
1927 | struct vm_struct *tmp; |
1928 | char *vaddr, *buf_start = buf; |
1929 | unsigned long buflen = count; |
1930 | unsigned long n; |
1931 | |
1932 | /* Don't allow overflow */ |
1933 | if ((unsigned long) addr + count < count) |
1934 | count = -(unsigned long) addr; |
1935 | |
1936 | read_lock(&vmlist_lock); |
1937 | for (tmp = vmlist; count && tmp; tmp = tmp->next) { |
1938 | vaddr = (char *) tmp->addr; |
1939 | if (addr >= vaddr + tmp->size - PAGE_SIZE) |
1940 | continue; |
1941 | while (addr < vaddr) { |
1942 | if (count == 0) |
1943 | goto finished; |
1944 | *buf = '\0'; |
1945 | buf++; |
1946 | addr++; |
1947 | count--; |
1948 | } |
1949 | n = vaddr + tmp->size - PAGE_SIZE - addr; |
1950 | if (n > count) |
1951 | n = count; |
1952 | if (!(tmp->flags & VM_IOREMAP)) |
1953 | aligned_vread(buf, addr, n); |
1954 | else /* IOREMAP area is treated as memory hole */ |
1955 | memset(buf, 0, n); |
1956 | buf += n; |
1957 | addr += n; |
1958 | count -= n; |
1959 | } |
1960 | finished: |
1961 | read_unlock(&vmlist_lock); |
1962 | |
1963 | if (buf == buf_start) |
1964 | return 0; |
1965 | /* zero-fill memory holes */ |
1966 | if (buf != buf_start + buflen) |
1967 | memset(buf, 0, buflen - (buf - buf_start)); |
1968 | |
1969 | return buflen; |
1970 | } |
1971 | |
1972 | /** |
1973 | * vwrite() - write vmalloc area in a safe way. |
1974 | * @buf: buffer for source data |
1975 | * @addr: vm address. |
1976 | * @count: number of bytes to be read. |
1977 | * |
1978 | * Returns # of bytes which addr and buf should be incresed. |
1979 | * (same number to @count). |
1980 | * If [addr...addr+count) doesn't includes any intersect with valid |
1981 | * vmalloc area, returns 0. |
1982 | * |
1983 | * This function checks that addr is a valid vmalloc'ed area, and |
1984 | * copy data from a buffer to the given addr. If specified range of |
1985 | * [addr...addr+count) includes some valid address, data is copied from |
1986 | * proper area of @buf. If there are memory holes, no copy to hole. |
1987 | * IOREMAP area is treated as memory hole and no copy is done. |
1988 | * |
1989 | * If [addr...addr+count) doesn't includes any intersects with alive |
1990 | * vm_struct area, returns 0. |
1991 | * @buf should be kernel's buffer. Because this function uses KM_USER0, |
1992 | * the caller should guarantee KM_USER0 is not used. |
1993 | * |
1994 | * Note: In usual ops, vwrite() is never necessary because the caller |
1995 | * should know vmalloc() area is valid and can use memcpy(). |
1996 | * This is for routines which have to access vmalloc area without |
1997 | * any informaion, as /dev/kmem. |
1998 | */ |
1999 | |
2000 | long vwrite(char *buf, char *addr, unsigned long count) |
2001 | { |
2002 | struct vm_struct *tmp; |
2003 | char *vaddr; |
2004 | unsigned long n, buflen; |
2005 | int copied = 0; |
2006 | |
2007 | /* Don't allow overflow */ |
2008 | if ((unsigned long) addr + count < count) |
2009 | count = -(unsigned long) addr; |
2010 | buflen = count; |
2011 | |
2012 | read_lock(&vmlist_lock); |
2013 | for (tmp = vmlist; count && tmp; tmp = tmp->next) { |
2014 | vaddr = (char *) tmp->addr; |
2015 | if (addr >= vaddr + tmp->size - PAGE_SIZE) |
2016 | continue; |
2017 | while (addr < vaddr) { |
2018 | if (count == 0) |
2019 | goto finished; |
2020 | buf++; |
2021 | addr++; |
2022 | count--; |
2023 | } |
2024 | n = vaddr + tmp->size - PAGE_SIZE - addr; |
2025 | if (n > count) |
2026 | n = count; |
2027 | if (!(tmp->flags & VM_IOREMAP)) { |
2028 | aligned_vwrite(buf, addr, n); |
2029 | copied++; |
2030 | } |
2031 | buf += n; |
2032 | addr += n; |
2033 | count -= n; |
2034 | } |
2035 | finished: |
2036 | read_unlock(&vmlist_lock); |
2037 | if (!copied) |
2038 | return 0; |
2039 | return buflen; |
2040 | } |
2041 | |
2042 | /** |
2043 | * remap_vmalloc_range - map vmalloc pages to userspace |
2044 | * @vma: vma to cover (map full range of vma) |
2045 | * @addr: vmalloc memory |
2046 | * @pgoff: number of pages into addr before first page to map |
2047 | * |
2048 | * Returns: 0 for success, -Exxx on failure |
2049 | * |
2050 | * This function checks that addr is a valid vmalloc'ed area, and |
2051 | * that it is big enough to cover the vma. Will return failure if |
2052 | * that criteria isn't met. |
2053 | * |
2054 | * Similar to remap_pfn_range() (see mm/memory.c) |
2055 | */ |
2056 | int remap_vmalloc_range(struct vm_area_struct *vma, void *addr, |
2057 | unsigned long pgoff) |
2058 | { |
2059 | struct vm_struct *area; |
2060 | unsigned long uaddr = vma->vm_start; |
2061 | unsigned long usize = vma->vm_end - vma->vm_start; |
2062 | |
2063 | if ((PAGE_SIZE-1) & (unsigned long)addr) |
2064 | return -EINVAL; |
2065 | |
2066 | area = find_vm_area(addr); |
2067 | if (!area) |
2068 | return -EINVAL; |
2069 | |
2070 | if (!(area->flags & VM_USERMAP)) |
2071 | return -EINVAL; |
2072 | |
2073 | if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE) |
2074 | return -EINVAL; |
2075 | |
2076 | addr += pgoff << PAGE_SHIFT; |
2077 | do { |
2078 | struct page *page = vmalloc_to_page(addr); |
2079 | int ret; |
2080 | |
2081 | ret = vm_insert_page(vma, uaddr, page); |
2082 | if (ret) |
2083 | return ret; |
2084 | |
2085 | uaddr += PAGE_SIZE; |
2086 | addr += PAGE_SIZE; |
2087 | usize -= PAGE_SIZE; |
2088 | } while (usize > 0); |
2089 | |
2090 | /* Prevent "things" like memory migration? VM_flags need a cleanup... */ |
2091 | vma->vm_flags |= VM_RESERVED; |
2092 | |
2093 | return 0; |
2094 | } |
2095 | EXPORT_SYMBOL(remap_vmalloc_range); |
2096 | |
2097 | /* |
2098 | * Implement a stub for vmalloc_sync_all() if the architecture chose not to |
2099 | * have one. |
2100 | */ |
2101 | void __attribute__((weak)) vmalloc_sync_all(void) |
2102 | { |
2103 | } |
2104 | |
2105 | |
2106 | static int f(pte_t *pte, pgtable_t table, unsigned long addr, void *data) |
2107 | { |
2108 | /* apply_to_page_range() does all the hard work. */ |
2109 | return 0; |
2110 | } |
2111 | |
2112 | /** |
2113 | * alloc_vm_area - allocate a range of kernel address space |
2114 | * @size: size of the area |
2115 | * |
2116 | * Returns: NULL on failure, vm_struct on success |
2117 | * |
2118 | * This function reserves a range of kernel address space, and |
2119 | * allocates pagetables to map that range. No actual mappings |
2120 | * are created. If the kernel address space is not shared |
2121 | * between processes, it syncs the pagetable across all |
2122 | * processes. |
2123 | */ |
2124 | struct vm_struct *alloc_vm_area(size_t size) |
2125 | { |
2126 | struct vm_struct *area; |
2127 | |
2128 | area = get_vm_area_caller(size, VM_IOREMAP, |
2129 | __builtin_return_address(0)); |
2130 | if (area == NULL) |
2131 | return NULL; |
2132 | |
2133 | /* |
2134 | * This ensures that page tables are constructed for this region |
2135 | * of kernel virtual address space and mapped into init_mm. |
2136 | */ |
2137 | if (apply_to_page_range(&init_mm, (unsigned long)area->addr, |
2138 | area->size, f, NULL)) { |
2139 | free_vm_area(area); |
2140 | return NULL; |
2141 | } |
2142 | |
2143 | /* |
2144 | * If the allocated address space is passed to a hypercall |
2145 | * before being used then we cannot rely on a page fault to |
2146 | * trigger an update of the page tables. So sync all the page |
2147 | * tables here. |
2148 | */ |
2149 | vmalloc_sync_all(); |
2150 | |
2151 | return area; |
2152 | } |
2153 | EXPORT_SYMBOL_GPL(alloc_vm_area); |
2154 | |
2155 | void free_vm_area(struct vm_struct *area) |
2156 | { |
2157 | struct vm_struct *ret; |
2158 | ret = remove_vm_area(area->addr); |
2159 | BUG_ON(ret != area); |
2160 | kfree(area); |
2161 | } |
2162 | EXPORT_SYMBOL_GPL(free_vm_area); |
2163 | |
2164 | #ifdef CONFIG_SMP |
2165 | static struct vmap_area *node_to_va(struct rb_node *n) |
2166 | { |
2167 | return n ? rb_entry(n, struct vmap_area, rb_node) : NULL; |
2168 | } |
2169 | |
2170 | /** |
2171 | * pvm_find_next_prev - find the next and prev vmap_area surrounding @end |
2172 | * @end: target address |
2173 | * @pnext: out arg for the next vmap_area |
2174 | * @pprev: out arg for the previous vmap_area |
2175 | * |
2176 | * Returns: %true if either or both of next and prev are found, |
2177 | * %false if no vmap_area exists |
2178 | * |
2179 | * Find vmap_areas end addresses of which enclose @end. ie. if not |
2180 | * NULL, *pnext->va_end > @end and *pprev->va_end <= @end. |
2181 | */ |
2182 | static bool pvm_find_next_prev(unsigned long end, |
2183 | struct vmap_area **pnext, |
2184 | struct vmap_area **pprev) |
2185 | { |
2186 | struct rb_node *n = vmap_area_root.rb_node; |
2187 | struct vmap_area *va = NULL; |
2188 | |
2189 | while (n) { |
2190 | va = rb_entry(n, struct vmap_area, rb_node); |
2191 | if (end < va->va_end) |
2192 | n = n->rb_left; |
2193 | else if (end > va->va_end) |
2194 | n = n->rb_right; |
2195 | else |
2196 | break; |
2197 | } |
2198 | |
2199 | if (!va) |
2200 | return false; |
2201 | |
2202 | if (va->va_end > end) { |
2203 | *pnext = va; |
2204 | *pprev = node_to_va(rb_prev(&(*pnext)->rb_node)); |
2205 | } else { |
2206 | *pprev = va; |
2207 | *pnext = node_to_va(rb_next(&(*pprev)->rb_node)); |
2208 | } |
2209 | return true; |
2210 | } |
2211 | |
2212 | /** |
2213 | * pvm_determine_end - find the highest aligned address between two vmap_areas |
2214 | * @pnext: in/out arg for the next vmap_area |
2215 | * @pprev: in/out arg for the previous vmap_area |
2216 | * @align: alignment |
2217 | * |
2218 | * Returns: determined end address |
2219 | * |
2220 | * Find the highest aligned address between *@pnext and *@pprev below |
2221 | * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned |
2222 | * down address is between the end addresses of the two vmap_areas. |
2223 | * |
2224 | * Please note that the address returned by this function may fall |
2225 | * inside *@pnext vmap_area. The caller is responsible for checking |
2226 | * that. |
2227 | */ |
2228 | static unsigned long pvm_determine_end(struct vmap_area **pnext, |
2229 | struct vmap_area **pprev, |
2230 | unsigned long align) |
2231 | { |
2232 | const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1); |
2233 | unsigned long addr; |
2234 | |
2235 | if (*pnext) |
2236 | addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end); |
2237 | else |
2238 | addr = vmalloc_end; |
2239 | |
2240 | while (*pprev && (*pprev)->va_end > addr) { |
2241 | *pnext = *pprev; |
2242 | *pprev = node_to_va(rb_prev(&(*pnext)->rb_node)); |
2243 | } |
2244 | |
2245 | return addr; |
2246 | } |
2247 | |
2248 | /** |
2249 | * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator |
2250 | * @offsets: array containing offset of each area |
2251 | * @sizes: array containing size of each area |
2252 | * @nr_vms: the number of areas to allocate |
2253 | * @align: alignment, all entries in @offsets and @sizes must be aligned to this |
2254 | * |
2255 | * Returns: kmalloc'd vm_struct pointer array pointing to allocated |
2256 | * vm_structs on success, %NULL on failure |
2257 | * |
2258 | * Percpu allocator wants to use congruent vm areas so that it can |
2259 | * maintain the offsets among percpu areas. This function allocates |
2260 | * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to |
2261 | * be scattered pretty far, distance between two areas easily going up |
2262 | * to gigabytes. To avoid interacting with regular vmallocs, these |
2263 | * areas are allocated from top. |
2264 | * |
2265 | * Despite its complicated look, this allocator is rather simple. It |
2266 | * does everything top-down and scans areas from the end looking for |
2267 | * matching slot. While scanning, if any of the areas overlaps with |
2268 | * existing vmap_area, the base address is pulled down to fit the |
2269 | * area. Scanning is repeated till all the areas fit and then all |
2270 | * necessary data structres are inserted and the result is returned. |
2271 | */ |
2272 | struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, |
2273 | const size_t *sizes, int nr_vms, |
2274 | size_t align) |
2275 | { |
2276 | const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align); |
2277 | const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1); |
2278 | struct vmap_area **vas, *prev, *next; |
2279 | struct vm_struct **vms; |
2280 | int area, area2, last_area, term_area; |
2281 | unsigned long base, start, end, last_end; |
2282 | bool purged = false; |
2283 | |
2284 | /* verify parameters and allocate data structures */ |
2285 | BUG_ON(align & ~PAGE_MASK || !is_power_of_2(align)); |
2286 | for (last_area = 0, area = 0; area < nr_vms; area++) { |
2287 | start = offsets[area]; |
2288 | end = start + sizes[area]; |
2289 | |
2290 | /* is everything aligned properly? */ |
2291 | BUG_ON(!IS_ALIGNED(offsets[area], align)); |
2292 | BUG_ON(!IS_ALIGNED(sizes[area], align)); |
2293 | |
2294 | /* detect the area with the highest address */ |
2295 | if (start > offsets[last_area]) |
2296 | last_area = area; |
2297 | |
2298 | for (area2 = 0; area2 < nr_vms; area2++) { |
2299 | unsigned long start2 = offsets[area2]; |
2300 | unsigned long end2 = start2 + sizes[area2]; |
2301 | |
2302 | if (area2 == area) |
2303 | continue; |
2304 | |
2305 | BUG_ON(start2 >= start && start2 < end); |
2306 | BUG_ON(end2 <= end && end2 > start); |
2307 | } |
2308 | } |
2309 | last_end = offsets[last_area] + sizes[last_area]; |
2310 | |
2311 | if (vmalloc_end - vmalloc_start < last_end) { |
2312 | WARN_ON(true); |
2313 | return NULL; |
2314 | } |
2315 | |
2316 | vms = kzalloc(sizeof(vms[0]) * nr_vms, GFP_KERNEL); |
2317 | vas = kzalloc(sizeof(vas[0]) * nr_vms, GFP_KERNEL); |
2318 | if (!vas || !vms) |
2319 | goto err_free; |
2320 | |
2321 | for (area = 0; area < nr_vms; area++) { |
2322 | vas[area] = kzalloc(sizeof(struct vmap_area), GFP_KERNEL); |
2323 | vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL); |
2324 | if (!vas[area] || !vms[area]) |
2325 | goto err_free; |
2326 | } |
2327 | retry: |
2328 | spin_lock(&vmap_area_lock); |
2329 | |
2330 | /* start scanning - we scan from the top, begin with the last area */ |
2331 | area = term_area = last_area; |
2332 | start = offsets[area]; |
2333 | end = start + sizes[area]; |
2334 | |
2335 | if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) { |
2336 | base = vmalloc_end - last_end; |
2337 | goto found; |
2338 | } |
2339 | base = pvm_determine_end(&next, &prev, align) - end; |
2340 | |
2341 | while (true) { |
2342 | BUG_ON(next && next->va_end <= base + end); |
2343 | BUG_ON(prev && prev->va_end > base + end); |
2344 | |
2345 | /* |
2346 | * base might have underflowed, add last_end before |
2347 | * comparing. |
2348 | */ |
2349 | if (base + last_end < vmalloc_start + last_end) { |
2350 | spin_unlock(&vmap_area_lock); |
2351 | if (!purged) { |
2352 | purge_vmap_area_lazy(); |
2353 | purged = true; |
2354 | goto retry; |
2355 | } |
2356 | goto err_free; |
2357 | } |
2358 | |
2359 | /* |
2360 | * If next overlaps, move base downwards so that it's |
2361 | * right below next and then recheck. |
2362 | */ |
2363 | if (next && next->va_start < base + end) { |
2364 | base = pvm_determine_end(&next, &prev, align) - end; |
2365 | term_area = area; |
2366 | continue; |
2367 | } |
2368 | |
2369 | /* |
2370 | * If prev overlaps, shift down next and prev and move |
2371 | * base so that it's right below new next and then |
2372 | * recheck. |
2373 | */ |
2374 | if (prev && prev->va_end > base + start) { |
2375 | next = prev; |
2376 | prev = node_to_va(rb_prev(&next->rb_node)); |
2377 | base = pvm_determine_end(&next, &prev, align) - end; |
2378 | term_area = area; |
2379 | continue; |
2380 | } |
2381 | |
2382 | /* |
2383 | * This area fits, move on to the previous one. If |
2384 | * the previous one is the terminal one, we're done. |
2385 | */ |
2386 | area = (area + nr_vms - 1) % nr_vms; |
2387 | if (area == term_area) |
2388 | break; |
2389 | start = offsets[area]; |
2390 | end = start + sizes[area]; |
2391 | pvm_find_next_prev(base + end, &next, &prev); |
2392 | } |
2393 | found: |
2394 | /* we've found a fitting base, insert all va's */ |
2395 | for (area = 0; area < nr_vms; area++) { |
2396 | struct vmap_area *va = vas[area]; |
2397 | |
2398 | va->va_start = base + offsets[area]; |
2399 | va->va_end = va->va_start + sizes[area]; |
2400 | __insert_vmap_area(va); |
2401 | } |
2402 | |
2403 | vmap_area_pcpu_hole = base + offsets[last_area]; |
2404 | |
2405 | spin_unlock(&vmap_area_lock); |
2406 | |
2407 | /* insert all vm's */ |
2408 | for (area = 0; area < nr_vms; area++) |
2409 | insert_vmalloc_vm(vms[area], vas[area], VM_ALLOC, |
2410 | pcpu_get_vm_areas); |
2411 | |
2412 | kfree(vas); |
2413 | return vms; |
2414 | |
2415 | err_free: |
2416 | for (area = 0; area < nr_vms; area++) { |
2417 | if (vas) |
2418 | kfree(vas[area]); |
2419 | if (vms) |
2420 | kfree(vms[area]); |
2421 | } |
2422 | kfree(vas); |
2423 | kfree(vms); |
2424 | return NULL; |
2425 | } |
2426 | |
2427 | /** |
2428 | * pcpu_free_vm_areas - free vmalloc areas for percpu allocator |
2429 | * @vms: vm_struct pointer array returned by pcpu_get_vm_areas() |
2430 | * @nr_vms: the number of allocated areas |
2431 | * |
2432 | * Free vm_structs and the array allocated by pcpu_get_vm_areas(). |
2433 | */ |
2434 | void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) |
2435 | { |
2436 | int i; |
2437 | |
2438 | for (i = 0; i < nr_vms; i++) |
2439 | free_vm_area(vms[i]); |
2440 | kfree(vms); |
2441 | } |
2442 | #endif /* CONFIG_SMP */ |
2443 | |
2444 | #ifdef CONFIG_PROC_FS |
2445 | static void *s_start(struct seq_file *m, loff_t *pos) |
2446 | __acquires(&vmlist_lock) |
2447 | { |
2448 | loff_t n = *pos; |
2449 | struct vm_struct *v; |
2450 | |
2451 | read_lock(&vmlist_lock); |
2452 | v = vmlist; |
2453 | while (n > 0 && v) { |
2454 | n--; |
2455 | v = v->next; |
2456 | } |
2457 | if (!n) |
2458 | return v; |
2459 | |
2460 | return NULL; |
2461 | |
2462 | } |
2463 | |
2464 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) |
2465 | { |
2466 | struct vm_struct *v = p; |
2467 | |
2468 | ++*pos; |
2469 | return v->next; |
2470 | } |
2471 | |
2472 | static void s_stop(struct seq_file *m, void *p) |
2473 | __releases(&vmlist_lock) |
2474 | { |
2475 | read_unlock(&vmlist_lock); |
2476 | } |
2477 | |
2478 | static void show_numa_info(struct seq_file *m, struct vm_struct *v) |
2479 | { |
2480 | if (NUMA_BUILD) { |
2481 | unsigned int nr, *counters = m->private; |
2482 | |
2483 | if (!counters) |
2484 | return; |
2485 | |
2486 | memset(counters, 0, nr_node_ids * sizeof(unsigned int)); |
2487 | |
2488 | for (nr = 0; nr < v->nr_pages; nr++) |
2489 | counters[page_to_nid(v->pages[nr])]++; |
2490 | |
2491 | for_each_node_state(nr, N_HIGH_MEMORY) |
2492 | if (counters[nr]) |
2493 | seq_printf(m, " N%u=%u", nr, counters[nr]); |
2494 | } |
2495 | } |
2496 | |
2497 | static int s_show(struct seq_file *m, void *p) |
2498 | { |
2499 | struct vm_struct *v = p; |
2500 | |
2501 | seq_printf(m, "0x%p-0x%p %7ld", |
2502 | v->addr, v->addr + v->size, v->size); |
2503 | |
2504 | if (v->caller) |
2505 | seq_printf(m, " %pS", v->caller); |
2506 | |
2507 | if (v->nr_pages) |
2508 | seq_printf(m, " pages=%d", v->nr_pages); |
2509 | |
2510 | if (v->phys_addr) |
2511 | seq_printf(m, " phys=%llx", (unsigned long long)v->phys_addr); |
2512 | |
2513 | if (v->flags & VM_IOREMAP) |
2514 | seq_printf(m, " ioremap"); |
2515 | |
2516 | if (v->flags & VM_ALLOC) |
2517 | seq_printf(m, " vmalloc"); |
2518 | |
2519 | if (v->flags & VM_MAP) |
2520 | seq_printf(m, " vmap"); |
2521 | |
2522 | if (v->flags & VM_USERMAP) |
2523 | seq_printf(m, " user"); |
2524 | |
2525 | if (v->flags & VM_VPAGES) |
2526 | seq_printf(m, " vpages"); |
2527 | |
2528 | show_numa_info(m, v); |
2529 | seq_putc(m, '\n'); |
2530 | return 0; |
2531 | } |
2532 | |
2533 | static const struct seq_operations vmalloc_op = { |
2534 | .start = s_start, |
2535 | .next = s_next, |
2536 | .stop = s_stop, |
2537 | .show = s_show, |
2538 | }; |
2539 | |
2540 | static int vmalloc_open(struct inode *inode, struct file *file) |
2541 | { |
2542 | unsigned int *ptr = NULL; |
2543 | int ret; |
2544 | |
2545 | if (NUMA_BUILD) { |
2546 | ptr = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL); |
2547 | if (ptr == NULL) |
2548 | return -ENOMEM; |
2549 | } |
2550 | ret = seq_open(file, &vmalloc_op); |
2551 | if (!ret) { |
2552 | struct seq_file *m = file->private_data; |
2553 | m->private = ptr; |
2554 | } else |
2555 | kfree(ptr); |
2556 | return ret; |
2557 | } |
2558 | |
2559 | static const struct file_operations proc_vmalloc_operations = { |
2560 | .open = vmalloc_open, |
2561 | .read = seq_read, |
2562 | .llseek = seq_lseek, |
2563 | .release = seq_release_private, |
2564 | }; |
2565 | |
2566 | static int __init proc_vmalloc_init(void) |
2567 | { |
2568 | proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations); |
2569 | return 0; |
2570 | } |
2571 | module_init(proc_vmalloc_init); |
2572 | #endif |
2573 | |
2574 |
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javiroman/ks7010
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Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9