blob: 6b8889da69a60612301c2bd26244ae0f3e1e1966 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Christoph Lameter930fc452005-10-29 18:15:41 -07008 * Numa awareness, Christoph Lameter, SGI, June 2005
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 */
10
Nick Piggindb64fe02008-10-18 20:27:03 -070011#include <linux/vmalloc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/mm.h>
13#include <linux/module.h>
14#include <linux/highmem.h>
Alexey Dobriyand43c36d2009-10-07 17:09:06 +040015#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/slab.h>
17#include <linux/spinlock.h>
18#include <linux/interrupt.h>
Alexey Dobriyan5f6a6a92008-10-06 03:50:47 +040019#include <linux/proc_fs.h>
Christoph Lametera10aa572008-04-28 02:12:40 -070020#include <linux/seq_file.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070021#include <linux/debugobjects.h>
Christoph Lameter23016962008-04-28 02:12:42 -070022#include <linux/kallsyms.h>
Nick Piggindb64fe02008-10-18 20:27:03 -070023#include <linux/list.h>
24#include <linux/rbtree.h>
25#include <linux/radix-tree.h>
26#include <linux/rcupdate.h>
Tejun Heof0aa6612009-02-20 16:29:08 +090027#include <linux/pfn.h>
Catalin Marinas89219d32009-06-11 13:23:19 +010028#include <linux/kmemleak.h>
Nick Piggindb64fe02008-10-18 20:27:03 -070029#include <asm/atomic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <asm/uaccess.h>
31#include <asm/tlbflush.h>
David Miller2dca6992009-09-21 12:22:34 -070032#include <asm/shmparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
Jeremy Fitzhardingea0d40c82010-03-26 15:28:51 -070034bool vmap_lazy_unmap __read_mostly = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Nick Piggindb64fe02008-10-18 20:27:03 -070036/*** Page table manipulation functions ***/
Adrian Bunkb2213852006-09-25 23:31:02 -070037
Linus Torvalds1da177e2005-04-16 15:20:36 -070038static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end)
39{
40 pte_t *pte;
41
42 pte = pte_offset_kernel(pmd, addr);
43 do {
44 pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
45 WARN_ON(!pte_none(ptent) && !pte_present(ptent));
46 } while (pte++, addr += PAGE_SIZE, addr != end);
47}
48
Nick Piggindb64fe02008-10-18 20:27:03 -070049static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
51 pmd_t *pmd;
52 unsigned long next;
53
54 pmd = pmd_offset(pud, addr);
55 do {
56 next = pmd_addr_end(addr, end);
57 if (pmd_none_or_clear_bad(pmd))
58 continue;
59 vunmap_pte_range(pmd, addr, next);
60 } while (pmd++, addr = next, addr != end);
61}
62
Nick Piggindb64fe02008-10-18 20:27:03 -070063static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end)
Linus Torvalds1da177e2005-04-16 15:20:36 -070064{
65 pud_t *pud;
66 unsigned long next;
67
68 pud = pud_offset(pgd, addr);
69 do {
70 next = pud_addr_end(addr, end);
71 if (pud_none_or_clear_bad(pud))
72 continue;
73 vunmap_pmd_range(pud, addr, next);
74 } while (pud++, addr = next, addr != end);
75}
76
Nick Piggindb64fe02008-10-18 20:27:03 -070077static void vunmap_page_range(unsigned long addr, unsigned long end)
Linus Torvalds1da177e2005-04-16 15:20:36 -070078{
79 pgd_t *pgd;
80 unsigned long next;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
82 BUG_ON(addr >= end);
83 pgd = pgd_offset_k(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 do {
85 next = pgd_addr_end(addr, end);
86 if (pgd_none_or_clear_bad(pgd))
87 continue;
88 vunmap_pud_range(pgd, addr, next);
89 } while (pgd++, addr = next, addr != end);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090}
91
92static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
Nick Piggindb64fe02008-10-18 20:27:03 -070093 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070094{
95 pte_t *pte;
96
Nick Piggindb64fe02008-10-18 20:27:03 -070097 /*
98 * nr is a running index into the array which helps higher level
99 * callers keep track of where we're up to.
100 */
101
Hugh Dickins872fec12005-10-29 18:16:21 -0700102 pte = pte_alloc_kernel(pmd, addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 if (!pte)
104 return -ENOMEM;
105 do {
Nick Piggindb64fe02008-10-18 20:27:03 -0700106 struct page *page = pages[*nr];
107
108 if (WARN_ON(!pte_none(*pte)))
109 return -EBUSY;
110 if (WARN_ON(!page))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 return -ENOMEM;
112 set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
Nick Piggindb64fe02008-10-18 20:27:03 -0700113 (*nr)++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 } while (pte++, addr += PAGE_SIZE, addr != end);
115 return 0;
116}
117
Nick Piggindb64fe02008-10-18 20:27:03 -0700118static int vmap_pmd_range(pud_t *pud, unsigned long addr,
119 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120{
121 pmd_t *pmd;
122 unsigned long next;
123
124 pmd = pmd_alloc(&init_mm, pud, addr);
125 if (!pmd)
126 return -ENOMEM;
127 do {
128 next = pmd_addr_end(addr, end);
Nick Piggindb64fe02008-10-18 20:27:03 -0700129 if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 return -ENOMEM;
131 } while (pmd++, addr = next, addr != end);
132 return 0;
133}
134
Nick Piggindb64fe02008-10-18 20:27:03 -0700135static int vmap_pud_range(pgd_t *pgd, unsigned long addr,
136 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137{
138 pud_t *pud;
139 unsigned long next;
140
141 pud = pud_alloc(&init_mm, pgd, addr);
142 if (!pud)
143 return -ENOMEM;
144 do {
145 next = pud_addr_end(addr, end);
Nick Piggindb64fe02008-10-18 20:27:03 -0700146 if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 return -ENOMEM;
148 } while (pud++, addr = next, addr != end);
149 return 0;
150}
151
Nick Piggindb64fe02008-10-18 20:27:03 -0700152/*
153 * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
154 * will have pfns corresponding to the "pages" array.
155 *
156 * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
157 */
Tejun Heo8fc48982009-02-20 16:29:08 +0900158static int vmap_page_range_noflush(unsigned long start, unsigned long end,
159 pgprot_t prot, struct page **pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160{
161 pgd_t *pgd;
162 unsigned long next;
Adam Lackorzynski2e4e27c2009-01-04 12:00:46 -0800163 unsigned long addr = start;
Nick Piggindb64fe02008-10-18 20:27:03 -0700164 int err = 0;
165 int nr = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166
167 BUG_ON(addr >= end);
168 pgd = pgd_offset_k(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 do {
170 next = pgd_addr_end(addr, end);
Nick Piggindb64fe02008-10-18 20:27:03 -0700171 err = vmap_pud_range(pgd, addr, next, prot, pages, &nr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 if (err)
Figo.zhangbf88c8c2009-09-21 17:01:47 -0700173 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 } while (pgd++, addr = next, addr != end);
Nick Piggindb64fe02008-10-18 20:27:03 -0700175
Nick Piggindb64fe02008-10-18 20:27:03 -0700176 return nr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177}
178
Tejun Heo8fc48982009-02-20 16:29:08 +0900179static int vmap_page_range(unsigned long start, unsigned long end,
180 pgprot_t prot, struct page **pages)
181{
182 int ret;
183
184 ret = vmap_page_range_noflush(start, end, prot, pages);
185 flush_cache_vmap(start, end);
186 return ret;
187}
188
KAMEZAWA Hiroyuki81ac3ad2009-09-22 16:45:49 -0700189int is_vmalloc_or_module_addr(const void *x)
Linus Torvalds73bdf0a2008-10-15 08:35:12 -0700190{
191 /*
Russell Kingab4f2ee2008-11-06 17:11:07 +0000192 * ARM, x86-64 and sparc64 put modules in a special place,
Linus Torvalds73bdf0a2008-10-15 08:35:12 -0700193 * and fall back on vmalloc() if that fails. Others
194 * just put it in the vmalloc space.
195 */
196#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
197 unsigned long addr = (unsigned long)x;
198 if (addr >= MODULES_VADDR && addr < MODULES_END)
199 return 1;
200#endif
201 return is_vmalloc_addr(x);
202}
203
Christoph Lameter48667e72008-02-04 22:28:31 -0800204/*
Nick Piggindb64fe02008-10-18 20:27:03 -0700205 * Walk a vmap address to the struct page it maps.
Christoph Lameter48667e72008-02-04 22:28:31 -0800206 */
Christoph Lameterb3bdda02008-02-04 22:28:32 -0800207struct page *vmalloc_to_page(const void *vmalloc_addr)
Christoph Lameter48667e72008-02-04 22:28:31 -0800208{
209 unsigned long addr = (unsigned long) vmalloc_addr;
210 struct page *page = NULL;
211 pgd_t *pgd = pgd_offset_k(addr);
Christoph Lameter48667e72008-02-04 22:28:31 -0800212
Ingo Molnar7aa413d2008-06-19 13:28:11 +0200213 /*
214 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
215 * architectures that do not vmalloc module space
216 */
Linus Torvalds73bdf0a2008-10-15 08:35:12 -0700217 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
Jiri Slaby59ea7462008-06-12 13:56:40 +0200218
Christoph Lameter48667e72008-02-04 22:28:31 -0800219 if (!pgd_none(*pgd)) {
Nick Piggindb64fe02008-10-18 20:27:03 -0700220 pud_t *pud = pud_offset(pgd, addr);
Christoph Lameter48667e72008-02-04 22:28:31 -0800221 if (!pud_none(*pud)) {
Nick Piggindb64fe02008-10-18 20:27:03 -0700222 pmd_t *pmd = pmd_offset(pud, addr);
Christoph Lameter48667e72008-02-04 22:28:31 -0800223 if (!pmd_none(*pmd)) {
Nick Piggindb64fe02008-10-18 20:27:03 -0700224 pte_t *ptep, pte;
225
Christoph Lameter48667e72008-02-04 22:28:31 -0800226 ptep = pte_offset_map(pmd, addr);
227 pte = *ptep;
228 if (pte_present(pte))
229 page = pte_page(pte);
230 pte_unmap(ptep);
231 }
232 }
233 }
234 return page;
235}
236EXPORT_SYMBOL(vmalloc_to_page);
237
238/*
239 * Map a vmalloc()-space virtual address to the physical page frame number.
240 */
Christoph Lameterb3bdda02008-02-04 22:28:32 -0800241unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
Christoph Lameter48667e72008-02-04 22:28:31 -0800242{
243 return page_to_pfn(vmalloc_to_page(vmalloc_addr));
244}
245EXPORT_SYMBOL(vmalloc_to_pfn);
246
Nick Piggindb64fe02008-10-18 20:27:03 -0700247
248/*** Global kva allocator ***/
249
250#define VM_LAZY_FREE 0x01
251#define VM_LAZY_FREEING 0x02
252#define VM_VM_AREA 0x04
253
254struct vmap_area {
255 unsigned long va_start;
256 unsigned long va_end;
257 unsigned long flags;
258 struct rb_node rb_node; /* address sorted rbtree */
259 struct list_head list; /* address sorted list */
260 struct list_head purge_list; /* "lazy purge" list */
261 void *private;
262 struct rcu_head rcu_head;
263};
264
265static DEFINE_SPINLOCK(vmap_area_lock);
266static struct rb_root vmap_area_root = RB_ROOT;
267static LIST_HEAD(vmap_area_list);
Tejun Heoca23e402009-08-14 15:00:52 +0900268static unsigned long vmap_area_pcpu_hole;
Nick Piggindb64fe02008-10-18 20:27:03 -0700269
270static struct vmap_area *__find_vmap_area(unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271{
Nick Piggindb64fe02008-10-18 20:27:03 -0700272 struct rb_node *n = vmap_area_root.rb_node;
273
274 while (n) {
275 struct vmap_area *va;
276
277 va = rb_entry(n, struct vmap_area, rb_node);
278 if (addr < va->va_start)
279 n = n->rb_left;
280 else if (addr > va->va_start)
281 n = n->rb_right;
282 else
283 return va;
284 }
285
286 return NULL;
287}
288
289static void __insert_vmap_area(struct vmap_area *va)
290{
291 struct rb_node **p = &vmap_area_root.rb_node;
292 struct rb_node *parent = NULL;
293 struct rb_node *tmp;
294
295 while (*p) {
296 struct vmap_area *tmp;
297
298 parent = *p;
299 tmp = rb_entry(parent, struct vmap_area, rb_node);
300 if (va->va_start < tmp->va_end)
301 p = &(*p)->rb_left;
302 else if (va->va_end > tmp->va_start)
303 p = &(*p)->rb_right;
304 else
305 BUG();
306 }
307
308 rb_link_node(&va->rb_node, parent, p);
309 rb_insert_color(&va->rb_node, &vmap_area_root);
310
311 /* address-sort this list so it is usable like the vmlist */
312 tmp = rb_prev(&va->rb_node);
313 if (tmp) {
314 struct vmap_area *prev;
315 prev = rb_entry(tmp, struct vmap_area, rb_node);
316 list_add_rcu(&va->list, &prev->list);
317 } else
318 list_add_rcu(&va->list, &vmap_area_list);
319}
320
321static void purge_vmap_area_lazy(void);
322
323/*
324 * Allocate a region of KVA of the specified size and alignment, within the
325 * vstart and vend.
326 */
327static struct vmap_area *alloc_vmap_area(unsigned long size,
328 unsigned long align,
329 unsigned long vstart, unsigned long vend,
330 int node, gfp_t gfp_mask)
331{
332 struct vmap_area *va;
333 struct rb_node *n;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 unsigned long addr;
Nick Piggindb64fe02008-10-18 20:27:03 -0700335 int purged = 0;
336
Nick Piggin77669702009-02-27 14:03:03 -0800337 BUG_ON(!size);
Nick Piggindb64fe02008-10-18 20:27:03 -0700338 BUG_ON(size & ~PAGE_MASK);
339
Nick Piggindb64fe02008-10-18 20:27:03 -0700340 va = kmalloc_node(sizeof(struct vmap_area),
341 gfp_mask & GFP_RECLAIM_MASK, node);
342 if (unlikely(!va))
343 return ERR_PTR(-ENOMEM);
344
345retry:
Glauber Costa0ae15132008-11-19 15:36:33 -0800346 addr = ALIGN(vstart, align);
347
Nick Piggindb64fe02008-10-18 20:27:03 -0700348 spin_lock(&vmap_area_lock);
Nick Piggin77669702009-02-27 14:03:03 -0800349 if (addr + size - 1 < addr)
350 goto overflow;
351
Nick Piggindb64fe02008-10-18 20:27:03 -0700352 /* XXX: could have a last_hole cache */
353 n = vmap_area_root.rb_node;
354 if (n) {
355 struct vmap_area *first = NULL;
356
357 do {
358 struct vmap_area *tmp;
359 tmp = rb_entry(n, struct vmap_area, rb_node);
360 if (tmp->va_end >= addr) {
361 if (!first && tmp->va_start < addr + size)
362 first = tmp;
363 n = n->rb_left;
364 } else {
365 first = tmp;
366 n = n->rb_right;
367 }
368 } while (n);
369
370 if (!first)
371 goto found;
372
373 if (first->va_end < addr) {
374 n = rb_next(&first->rb_node);
375 if (n)
376 first = rb_entry(n, struct vmap_area, rb_node);
377 else
378 goto found;
379 }
380
Nick Pigginf011c2d2008-11-19 15:36:32 -0800381 while (addr + size > first->va_start && addr + size <= vend) {
Nick Piggindb64fe02008-10-18 20:27:03 -0700382 addr = ALIGN(first->va_end + PAGE_SIZE, align);
Nick Piggin77669702009-02-27 14:03:03 -0800383 if (addr + size - 1 < addr)
384 goto overflow;
Nick Piggindb64fe02008-10-18 20:27:03 -0700385
386 n = rb_next(&first->rb_node);
387 if (n)
388 first = rb_entry(n, struct vmap_area, rb_node);
389 else
390 goto found;
391 }
392 }
393found:
394 if (addr + size > vend) {
Nick Piggin77669702009-02-27 14:03:03 -0800395overflow:
Nick Piggindb64fe02008-10-18 20:27:03 -0700396 spin_unlock(&vmap_area_lock);
397 if (!purged) {
398 purge_vmap_area_lazy();
399 purged = 1;
400 goto retry;
401 }
402 if (printk_ratelimit())
Glauber Costac1279c42009-01-06 14:39:18 -0800403 printk(KERN_WARNING
404 "vmap allocation for size %lu failed: "
405 "use vmalloc=<size> to increase size.\n", size);
Ralph Wuerthner2498ce42009-05-06 16:02:59 -0700406 kfree(va);
Nick Piggindb64fe02008-10-18 20:27:03 -0700407 return ERR_PTR(-EBUSY);
408 }
409
410 BUG_ON(addr & (align-1));
411
412 va->va_start = addr;
413 va->va_end = addr + size;
414 va->flags = 0;
415 __insert_vmap_area(va);
416 spin_unlock(&vmap_area_lock);
417
418 return va;
419}
420
421static void rcu_free_va(struct rcu_head *head)
422{
423 struct vmap_area *va = container_of(head, struct vmap_area, rcu_head);
424
425 kfree(va);
426}
427
428static void __free_vmap_area(struct vmap_area *va)
429{
430 BUG_ON(RB_EMPTY_NODE(&va->rb_node));
431 rb_erase(&va->rb_node, &vmap_area_root);
432 RB_CLEAR_NODE(&va->rb_node);
433 list_del_rcu(&va->list);
434
Tejun Heoca23e402009-08-14 15:00:52 +0900435 /*
436 * Track the highest possible candidate for pcpu area
437 * allocation. Areas outside of vmalloc area can be returned
438 * here too, consider only end addresses which fall inside
439 * vmalloc area proper.
440 */
441 if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END)
442 vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end);
443
Nick Piggindb64fe02008-10-18 20:27:03 -0700444 call_rcu(&va->rcu_head, rcu_free_va);
445}
446
447/*
448 * Free a region of KVA allocated by alloc_vmap_area
449 */
450static void free_vmap_area(struct vmap_area *va)
451{
452 spin_lock(&vmap_area_lock);
453 __free_vmap_area(va);
454 spin_unlock(&vmap_area_lock);
455}
456
457/*
458 * Clear the pagetable entries of a given vmap_area
459 */
460static void unmap_vmap_area(struct vmap_area *va)
461{
462 vunmap_page_range(va->va_start, va->va_end);
463}
464
Nick Piggincd528582009-01-06 14:39:20 -0800465static void vmap_debug_free_range(unsigned long start, unsigned long end)
466{
467 /*
468 * Unmap page tables and force a TLB flush immediately if
469 * CONFIG_DEBUG_PAGEALLOC is set. This catches use after free
470 * bugs similarly to those in linear kernel virtual address
471 * space after a page has been freed.
472 *
473 * All the lazy freeing logic is still retained, in order to
474 * minimise intrusiveness of this debugging feature.
475 *
476 * This is going to be *slow* (linear kernel virtual address
477 * debugging doesn't do a broadcast TLB flush so it is a lot
478 * faster).
479 */
480#ifdef CONFIG_DEBUG_PAGEALLOC
481 vunmap_page_range(start, end);
482 flush_tlb_kernel_range(start, end);
483#endif
484}
485
Nick Piggindb64fe02008-10-18 20:27:03 -0700486/*
487 * lazy_max_pages is the maximum amount of virtual address space we gather up
488 * before attempting to purge with a TLB flush.
489 *
490 * There is a tradeoff here: a larger number will cover more kernel page tables
491 * and take slightly longer to purge, but it will linearly reduce the number of
492 * global TLB flushes that must be performed. It would seem natural to scale
493 * this number up linearly with the number of CPUs (because vmapping activity
494 * could also scale linearly with the number of CPUs), however it is likely
495 * that in practice, workloads might be constrained in other ways that mean
496 * vmap activity will not scale linearly with CPUs. Also, I want to be
497 * conservative and not introduce a big latency on huge systems, so go with
498 * a less aggressive log scale. It will still be an improvement over the old
499 * code, and it will be simple to change the scale factor if we find that it
500 * becomes a problem on bigger systems.
501 */
502static unsigned long lazy_max_pages(void)
503{
504 unsigned int log;
505
Jeremy Fitzhardingea0d40c82010-03-26 15:28:51 -0700506 if (!vmap_lazy_unmap)
507 return 0;
508
Nick Piggindb64fe02008-10-18 20:27:03 -0700509 log = fls(num_online_cpus());
510
511 return log * (32UL * 1024 * 1024 / PAGE_SIZE);
512}
513
514static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
515
Nick Piggin02b709d2010-02-01 22:25:57 +1100516/* for per-CPU blocks */
517static void purge_fragmented_blocks_allcpus(void);
518
Nick Piggindb64fe02008-10-18 20:27:03 -0700519/*
520 * Purges all lazily-freed vmap areas.
521 *
522 * If sync is 0 then don't purge if there is already a purge in progress.
523 * If force_flush is 1, then flush kernel TLBs between *start and *end even
524 * if we found no lazy vmap areas to unmap (callers can use this to optimise
525 * their own TLB flushing).
526 * Returns with *start = min(*start, lowest purged address)
527 * *end = max(*end, highest purged address)
528 */
529static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
530 int sync, int force_flush)
531{
Andrew Morton46666d82009-01-15 13:51:15 -0800532 static DEFINE_SPINLOCK(purge_lock);
Nick Piggindb64fe02008-10-18 20:27:03 -0700533 LIST_HEAD(valist);
534 struct vmap_area *va;
Vegard Nossumcbb76672009-02-27 14:03:04 -0800535 struct vmap_area *n_va;
Nick Piggindb64fe02008-10-18 20:27:03 -0700536 int nr = 0;
537
538 /*
539 * If sync is 0 but force_flush is 1, we'll go sync anyway but callers
540 * should not expect such behaviour. This just simplifies locking for
541 * the case that isn't actually used at the moment anyway.
542 */
543 if (!sync && !force_flush) {
Andrew Morton46666d82009-01-15 13:51:15 -0800544 if (!spin_trylock(&purge_lock))
Nick Piggindb64fe02008-10-18 20:27:03 -0700545 return;
546 } else
Andrew Morton46666d82009-01-15 13:51:15 -0800547 spin_lock(&purge_lock);
Nick Piggindb64fe02008-10-18 20:27:03 -0700548
Nick Piggin02b709d2010-02-01 22:25:57 +1100549 if (sync)
550 purge_fragmented_blocks_allcpus();
551
Nick Piggindb64fe02008-10-18 20:27:03 -0700552 rcu_read_lock();
553 list_for_each_entry_rcu(va, &vmap_area_list, list) {
554 if (va->flags & VM_LAZY_FREE) {
555 if (va->va_start < *start)
556 *start = va->va_start;
557 if (va->va_end > *end)
558 *end = va->va_end;
559 nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
560 unmap_vmap_area(va);
561 list_add_tail(&va->purge_list, &valist);
562 va->flags |= VM_LAZY_FREEING;
563 va->flags &= ~VM_LAZY_FREE;
564 }
565 }
566 rcu_read_unlock();
567
Yongseok Koh88f50042010-01-19 17:33:49 +0900568 if (nr)
Nick Piggindb64fe02008-10-18 20:27:03 -0700569 atomic_sub(nr, &vmap_lazy_nr);
Nick Piggindb64fe02008-10-18 20:27:03 -0700570
571 if (nr || force_flush)
572 flush_tlb_kernel_range(*start, *end);
573
574 if (nr) {
575 spin_lock(&vmap_area_lock);
Vegard Nossumcbb76672009-02-27 14:03:04 -0800576 list_for_each_entry_safe(va, n_va, &valist, purge_list)
Nick Piggindb64fe02008-10-18 20:27:03 -0700577 __free_vmap_area(va);
578 spin_unlock(&vmap_area_lock);
579 }
Andrew Morton46666d82009-01-15 13:51:15 -0800580 spin_unlock(&purge_lock);
Nick Piggindb64fe02008-10-18 20:27:03 -0700581}
582
583/*
Nick Piggin496850e2008-11-19 15:36:33 -0800584 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
585 * is already purging.
586 */
587static void try_purge_vmap_area_lazy(void)
588{
589 unsigned long start = ULONG_MAX, end = 0;
590
591 __purge_vmap_area_lazy(&start, &end, 0, 0);
592}
593
594/*
Nick Piggindb64fe02008-10-18 20:27:03 -0700595 * Kick off a purge of the outstanding lazy areas.
596 */
597static void purge_vmap_area_lazy(void)
598{
599 unsigned long start = ULONG_MAX, end = 0;
600
Nick Piggin496850e2008-11-19 15:36:33 -0800601 __purge_vmap_area_lazy(&start, &end, 1, 0);
Nick Piggindb64fe02008-10-18 20:27:03 -0700602}
603
604/*
Nick Pigginb29acbd2008-12-01 13:13:47 -0800605 * Free and unmap a vmap area, caller ensuring flush_cache_vunmap had been
606 * called for the correct range previously.
Nick Piggindb64fe02008-10-18 20:27:03 -0700607 */
Nick Pigginb29acbd2008-12-01 13:13:47 -0800608static void free_unmap_vmap_area_noflush(struct vmap_area *va)
Nick Piggindb64fe02008-10-18 20:27:03 -0700609{
610 va->flags |= VM_LAZY_FREE;
611 atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr);
612 if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages()))
Nick Piggin496850e2008-11-19 15:36:33 -0800613 try_purge_vmap_area_lazy();
Nick Piggindb64fe02008-10-18 20:27:03 -0700614}
615
Nick Pigginb29acbd2008-12-01 13:13:47 -0800616/*
617 * Free and unmap a vmap area
618 */
619static void free_unmap_vmap_area(struct vmap_area *va)
620{
621 flush_cache_vunmap(va->va_start, va->va_end);
622 free_unmap_vmap_area_noflush(va);
623}
624
Nick Piggindb64fe02008-10-18 20:27:03 -0700625static struct vmap_area *find_vmap_area(unsigned long addr)
626{
627 struct vmap_area *va;
628
629 spin_lock(&vmap_area_lock);
630 va = __find_vmap_area(addr);
631 spin_unlock(&vmap_area_lock);
632
633 return va;
634}
635
636static void free_unmap_vmap_area_addr(unsigned long addr)
637{
638 struct vmap_area *va;
639
640 va = find_vmap_area(addr);
641 BUG_ON(!va);
642 free_unmap_vmap_area(va);
643}
644
645
646/*** Per cpu kva allocator ***/
647
648/*
649 * vmap space is limited especially on 32 bit architectures. Ensure there is
650 * room for at least 16 percpu vmap blocks per CPU.
651 */
652/*
653 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
654 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
655 * instead (we just need a rough idea)
656 */
657#if BITS_PER_LONG == 32
658#define VMALLOC_SPACE (128UL*1024*1024)
659#else
660#define VMALLOC_SPACE (128UL*1024*1024*1024)
661#endif
662
663#define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
664#define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
665#define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
666#define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
667#define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
668#define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
669#define VMAP_BBMAP_BITS VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
670 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
671 VMALLOC_PAGES / NR_CPUS / 16))
672
673#define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
674
Jeremy Fitzhardinge9b463332008-10-28 19:22:34 +1100675static bool vmap_initialized __read_mostly = false;
676
Nick Piggindb64fe02008-10-18 20:27:03 -0700677struct vmap_block_queue {
678 spinlock_t lock;
679 struct list_head free;
Nick Piggindb64fe02008-10-18 20:27:03 -0700680};
681
682struct vmap_block {
683 spinlock_t lock;
684 struct vmap_area *va;
685 struct vmap_block_queue *vbq;
686 unsigned long free, dirty;
687 DECLARE_BITMAP(alloc_map, VMAP_BBMAP_BITS);
688 DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS);
Nick Pigginde560422010-02-01 22:24:18 +1100689 struct list_head free_list;
690 struct rcu_head rcu_head;
Nick Piggin02b709d2010-02-01 22:25:57 +1100691 struct list_head purge;
Nick Piggindb64fe02008-10-18 20:27:03 -0700692};
693
694/* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
695static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
696
697/*
698 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
699 * in the free path. Could get rid of this if we change the API to return a
700 * "cookie" from alloc, to be passed to free. But no big deal yet.
701 */
702static DEFINE_SPINLOCK(vmap_block_tree_lock);
703static RADIX_TREE(vmap_block_tree, GFP_ATOMIC);
704
705/*
706 * We should probably have a fallback mechanism to allocate virtual memory
707 * out of partially filled vmap blocks. However vmap block sizing should be
708 * fairly reasonable according to the vmalloc size, so it shouldn't be a
709 * big problem.
710 */
711
712static unsigned long addr_to_vb_idx(unsigned long addr)
713{
714 addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
715 addr /= VMAP_BLOCK_SIZE;
716 return addr;
717}
718
719static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
720{
721 struct vmap_block_queue *vbq;
722 struct vmap_block *vb;
723 struct vmap_area *va;
724 unsigned long vb_idx;
725 int node, err;
726
727 node = numa_node_id();
728
729 vb = kmalloc_node(sizeof(struct vmap_block),
730 gfp_mask & GFP_RECLAIM_MASK, node);
731 if (unlikely(!vb))
732 return ERR_PTR(-ENOMEM);
733
734 va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
735 VMALLOC_START, VMALLOC_END,
736 node, gfp_mask);
737 if (unlikely(IS_ERR(va))) {
738 kfree(vb);
Julia Lawalle7d86342010-08-09 17:18:28 -0700739 return ERR_CAST(va);
Nick Piggindb64fe02008-10-18 20:27:03 -0700740 }
741
742 err = radix_tree_preload(gfp_mask);
743 if (unlikely(err)) {
744 kfree(vb);
745 free_vmap_area(va);
746 return ERR_PTR(err);
747 }
748
749 spin_lock_init(&vb->lock);
750 vb->va = va;
751 vb->free = VMAP_BBMAP_BITS;
752 vb->dirty = 0;
753 bitmap_zero(vb->alloc_map, VMAP_BBMAP_BITS);
754 bitmap_zero(vb->dirty_map, VMAP_BBMAP_BITS);
755 INIT_LIST_HEAD(&vb->free_list);
Nick Piggindb64fe02008-10-18 20:27:03 -0700756
757 vb_idx = addr_to_vb_idx(va->va_start);
758 spin_lock(&vmap_block_tree_lock);
759 err = radix_tree_insert(&vmap_block_tree, vb_idx, vb);
760 spin_unlock(&vmap_block_tree_lock);
761 BUG_ON(err);
762 radix_tree_preload_end();
763
764 vbq = &get_cpu_var(vmap_block_queue);
765 vb->vbq = vbq;
766 spin_lock(&vbq->lock);
Nick Pigginde560422010-02-01 22:24:18 +1100767 list_add_rcu(&vb->free_list, &vbq->free);
Nick Piggindb64fe02008-10-18 20:27:03 -0700768 spin_unlock(&vbq->lock);
Tejun Heo3f04ba82009-10-29 22:34:12 +0900769 put_cpu_var(vmap_block_queue);
Nick Piggindb64fe02008-10-18 20:27:03 -0700770
771 return vb;
772}
773
774static void rcu_free_vb(struct rcu_head *head)
775{
776 struct vmap_block *vb = container_of(head, struct vmap_block, rcu_head);
777
778 kfree(vb);
779}
780
781static void free_vmap_block(struct vmap_block *vb)
782{
783 struct vmap_block *tmp;
784 unsigned long vb_idx;
785
Nick Piggindb64fe02008-10-18 20:27:03 -0700786 vb_idx = addr_to_vb_idx(vb->va->va_start);
787 spin_lock(&vmap_block_tree_lock);
788 tmp = radix_tree_delete(&vmap_block_tree, vb_idx);
789 spin_unlock(&vmap_block_tree_lock);
790 BUG_ON(tmp != vb);
791
Nick Pigginb29acbd2008-12-01 13:13:47 -0800792 free_unmap_vmap_area_noflush(vb->va);
Nick Piggindb64fe02008-10-18 20:27:03 -0700793 call_rcu(&vb->rcu_head, rcu_free_vb);
794}
795
Nick Piggin02b709d2010-02-01 22:25:57 +1100796static void purge_fragmented_blocks(int cpu)
797{
798 LIST_HEAD(purge);
799 struct vmap_block *vb;
800 struct vmap_block *n_vb;
801 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
802
803 rcu_read_lock();
804 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
805
806 if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
807 continue;
808
809 spin_lock(&vb->lock);
810 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
811 vb->free = 0; /* prevent further allocs after releasing lock */
812 vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
813 bitmap_fill(vb->alloc_map, VMAP_BBMAP_BITS);
814 bitmap_fill(vb->dirty_map, VMAP_BBMAP_BITS);
815 spin_lock(&vbq->lock);
816 list_del_rcu(&vb->free_list);
817 spin_unlock(&vbq->lock);
818 spin_unlock(&vb->lock);
819 list_add_tail(&vb->purge, &purge);
820 } else
821 spin_unlock(&vb->lock);
822 }
823 rcu_read_unlock();
824
825 list_for_each_entry_safe(vb, n_vb, &purge, purge) {
826 list_del(&vb->purge);
827 free_vmap_block(vb);
828 }
829}
830
831static void purge_fragmented_blocks_thiscpu(void)
832{
833 purge_fragmented_blocks(smp_processor_id());
834}
835
836static void purge_fragmented_blocks_allcpus(void)
837{
838 int cpu;
839
840 for_each_possible_cpu(cpu)
841 purge_fragmented_blocks(cpu);
842}
843
Nick Piggindb64fe02008-10-18 20:27:03 -0700844static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
845{
846 struct vmap_block_queue *vbq;
847 struct vmap_block *vb;
848 unsigned long addr = 0;
849 unsigned int order;
Nick Piggin02b709d2010-02-01 22:25:57 +1100850 int purge = 0;
Nick Piggindb64fe02008-10-18 20:27:03 -0700851
852 BUG_ON(size & ~PAGE_MASK);
853 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
854 order = get_order(size);
855
856again:
857 rcu_read_lock();
858 vbq = &get_cpu_var(vmap_block_queue);
859 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
860 int i;
861
862 spin_lock(&vb->lock);
Nick Piggin02b709d2010-02-01 22:25:57 +1100863 if (vb->free < 1UL << order)
864 goto next;
865
Nick Piggindb64fe02008-10-18 20:27:03 -0700866 i = bitmap_find_free_region(vb->alloc_map,
867 VMAP_BBMAP_BITS, order);
868
Nick Piggin02b709d2010-02-01 22:25:57 +1100869 if (i < 0) {
870 if (vb->free + vb->dirty == VMAP_BBMAP_BITS) {
871 /* fragmented and no outstanding allocations */
872 BUG_ON(vb->dirty != VMAP_BBMAP_BITS);
873 purge = 1;
Nick Piggindb64fe02008-10-18 20:27:03 -0700874 }
Nick Piggin02b709d2010-02-01 22:25:57 +1100875 goto next;
876 }
877 addr = vb->va->va_start + (i << PAGE_SHIFT);
878 BUG_ON(addr_to_vb_idx(addr) !=
879 addr_to_vb_idx(vb->va->va_start));
880 vb->free -= 1UL << order;
881 if (vb->free == 0) {
882 spin_lock(&vbq->lock);
883 list_del_rcu(&vb->free_list);
884 spin_unlock(&vbq->lock);
Nick Piggindb64fe02008-10-18 20:27:03 -0700885 }
886 spin_unlock(&vb->lock);
Nick Piggin02b709d2010-02-01 22:25:57 +1100887 break;
888next:
889 spin_unlock(&vb->lock);
Nick Piggindb64fe02008-10-18 20:27:03 -0700890 }
Nick Piggin02b709d2010-02-01 22:25:57 +1100891
892 if (purge)
893 purge_fragmented_blocks_thiscpu();
894
Tejun Heo3f04ba82009-10-29 22:34:12 +0900895 put_cpu_var(vmap_block_queue);
Nick Piggindb64fe02008-10-18 20:27:03 -0700896 rcu_read_unlock();
897
898 if (!addr) {
899 vb = new_vmap_block(gfp_mask);
900 if (IS_ERR(vb))
901 return vb;
902 goto again;
903 }
904
905 return (void *)addr;
906}
907
908static void vb_free(const void *addr, unsigned long size)
909{
910 unsigned long offset;
911 unsigned long vb_idx;
912 unsigned int order;
913 struct vmap_block *vb;
914
915 BUG_ON(size & ~PAGE_MASK);
916 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
Nick Pigginb29acbd2008-12-01 13:13:47 -0800917
918 flush_cache_vunmap((unsigned long)addr, (unsigned long)addr + size);
919
Nick Piggindb64fe02008-10-18 20:27:03 -0700920 order = get_order(size);
921
922 offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1);
923
924 vb_idx = addr_to_vb_idx((unsigned long)addr);
925 rcu_read_lock();
926 vb = radix_tree_lookup(&vmap_block_tree, vb_idx);
927 rcu_read_unlock();
928 BUG_ON(!vb);
929
930 spin_lock(&vb->lock);
Nick Pigginde560422010-02-01 22:24:18 +1100931 BUG_ON(bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order));
MinChan Kimd0868172009-03-31 15:19:26 -0700932
Nick Piggindb64fe02008-10-18 20:27:03 -0700933 vb->dirty += 1UL << order;
934 if (vb->dirty == VMAP_BBMAP_BITS) {
Nick Pigginde560422010-02-01 22:24:18 +1100935 BUG_ON(vb->free);
Nick Piggindb64fe02008-10-18 20:27:03 -0700936 spin_unlock(&vb->lock);
937 free_vmap_block(vb);
938 } else
939 spin_unlock(&vb->lock);
940}
941
942/**
943 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
944 *
945 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
946 * to amortize TLB flushing overheads. What this means is that any page you
947 * have now, may, in a former life, have been mapped into kernel virtual
948 * address by the vmap layer and so there might be some CPUs with TLB entries
949 * still referencing that page (additional to the regular 1:1 kernel mapping).
950 *
951 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
952 * be sure that none of the pages we have control over will have any aliases
953 * from the vmap layer.
954 */
955void vm_unmap_aliases(void)
956{
957 unsigned long start = ULONG_MAX, end = 0;
958 int cpu;
959 int flush = 0;
960
Jeremy Fitzhardinge9b463332008-10-28 19:22:34 +1100961 if (unlikely(!vmap_initialized))
962 return;
963
Nick Piggindb64fe02008-10-18 20:27:03 -0700964 for_each_possible_cpu(cpu) {
965 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
966 struct vmap_block *vb;
967
968 rcu_read_lock();
969 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
970 int i;
971
972 spin_lock(&vb->lock);
973 i = find_first_bit(vb->dirty_map, VMAP_BBMAP_BITS);
974 while (i < VMAP_BBMAP_BITS) {
975 unsigned long s, e;
976 int j;
977 j = find_next_zero_bit(vb->dirty_map,
978 VMAP_BBMAP_BITS, i);
979
980 s = vb->va->va_start + (i << PAGE_SHIFT);
981 e = vb->va->va_start + (j << PAGE_SHIFT);
982 vunmap_page_range(s, e);
983 flush = 1;
984
985 if (s < start)
986 start = s;
987 if (e > end)
988 end = e;
989
990 i = j;
991 i = find_next_bit(vb->dirty_map,
992 VMAP_BBMAP_BITS, i);
993 }
994 spin_unlock(&vb->lock);
995 }
996 rcu_read_unlock();
997 }
998
999 __purge_vmap_area_lazy(&start, &end, 1, flush);
1000}
1001EXPORT_SYMBOL_GPL(vm_unmap_aliases);
1002
1003/**
1004 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1005 * @mem: the pointer returned by vm_map_ram
1006 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1007 */
1008void vm_unmap_ram(const void *mem, unsigned int count)
1009{
1010 unsigned long size = count << PAGE_SHIFT;
1011 unsigned long addr = (unsigned long)mem;
1012
1013 BUG_ON(!addr);
1014 BUG_ON(addr < VMALLOC_START);
1015 BUG_ON(addr > VMALLOC_END);
1016 BUG_ON(addr & (PAGE_SIZE-1));
1017
1018 debug_check_no_locks_freed(mem, size);
Nick Piggincd528582009-01-06 14:39:20 -08001019 vmap_debug_free_range(addr, addr+size);
Nick Piggindb64fe02008-10-18 20:27:03 -07001020
1021 if (likely(count <= VMAP_MAX_ALLOC))
1022 vb_free(mem, size);
1023 else
1024 free_unmap_vmap_area_addr(addr);
1025}
1026EXPORT_SYMBOL(vm_unmap_ram);
1027
1028/**
1029 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1030 * @pages: an array of pointers to the pages to be mapped
1031 * @count: number of pages
1032 * @node: prefer to allocate data structures on this node
1033 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
Randy Dunlape99c97a2008-10-29 14:01:09 -07001034 *
1035 * Returns: a pointer to the address that has been mapped, or %NULL on failure
Nick Piggindb64fe02008-10-18 20:27:03 -07001036 */
1037void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
1038{
1039 unsigned long size = count << PAGE_SHIFT;
1040 unsigned long addr;
1041 void *mem;
1042
1043 if (likely(count <= VMAP_MAX_ALLOC)) {
1044 mem = vb_alloc(size, GFP_KERNEL);
1045 if (IS_ERR(mem))
1046 return NULL;
1047 addr = (unsigned long)mem;
1048 } else {
1049 struct vmap_area *va;
1050 va = alloc_vmap_area(size, PAGE_SIZE,
1051 VMALLOC_START, VMALLOC_END, node, GFP_KERNEL);
1052 if (IS_ERR(va))
1053 return NULL;
1054
1055 addr = va->va_start;
1056 mem = (void *)addr;
1057 }
1058 if (vmap_page_range(addr, addr + size, prot, pages) < 0) {
1059 vm_unmap_ram(mem, count);
1060 return NULL;
1061 }
1062 return mem;
1063}
1064EXPORT_SYMBOL(vm_map_ram);
1065
Tejun Heof0aa6612009-02-20 16:29:08 +09001066/**
1067 * vm_area_register_early - register vmap area early during boot
1068 * @vm: vm_struct to register
Tejun Heoc0c0a292009-02-24 11:57:21 +09001069 * @align: requested alignment
Tejun Heof0aa6612009-02-20 16:29:08 +09001070 *
1071 * This function is used to register kernel vm area before
1072 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1073 * proper values on entry and other fields should be zero. On return,
1074 * vm->addr contains the allocated address.
1075 *
1076 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1077 */
Tejun Heoc0c0a292009-02-24 11:57:21 +09001078void __init vm_area_register_early(struct vm_struct *vm, size_t align)
Tejun Heof0aa6612009-02-20 16:29:08 +09001079{
1080 static size_t vm_init_off __initdata;
Tejun Heoc0c0a292009-02-24 11:57:21 +09001081 unsigned long addr;
Tejun Heof0aa6612009-02-20 16:29:08 +09001082
Tejun Heoc0c0a292009-02-24 11:57:21 +09001083 addr = ALIGN(VMALLOC_START + vm_init_off, align);
1084 vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START;
1085
1086 vm->addr = (void *)addr;
Tejun Heof0aa6612009-02-20 16:29:08 +09001087
1088 vm->next = vmlist;
1089 vmlist = vm;
1090}
1091
Nick Piggindb64fe02008-10-18 20:27:03 -07001092void __init vmalloc_init(void)
1093{
Ivan Kokshaysky822c18f2009-01-15 13:50:48 -08001094 struct vmap_area *va;
1095 struct vm_struct *tmp;
Nick Piggindb64fe02008-10-18 20:27:03 -07001096 int i;
1097
1098 for_each_possible_cpu(i) {
1099 struct vmap_block_queue *vbq;
1100
1101 vbq = &per_cpu(vmap_block_queue, i);
1102 spin_lock_init(&vbq->lock);
1103 INIT_LIST_HEAD(&vbq->free);
Nick Piggindb64fe02008-10-18 20:27:03 -07001104 }
Jeremy Fitzhardinge9b463332008-10-28 19:22:34 +11001105
Ivan Kokshaysky822c18f2009-01-15 13:50:48 -08001106 /* Import existing vmlist entries. */
1107 for (tmp = vmlist; tmp; tmp = tmp->next) {
Pekka Enberg43ebdac2009-05-25 15:01:35 +03001108 va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT);
Ivan Kokshaysky822c18f2009-01-15 13:50:48 -08001109 va->flags = tmp->flags | VM_VM_AREA;
1110 va->va_start = (unsigned long)tmp->addr;
1111 va->va_end = va->va_start + tmp->size;
1112 __insert_vmap_area(va);
1113 }
Tejun Heoca23e402009-08-14 15:00:52 +09001114
1115 vmap_area_pcpu_hole = VMALLOC_END;
1116
Jeremy Fitzhardinge9b463332008-10-28 19:22:34 +11001117 vmap_initialized = true;
Nick Piggindb64fe02008-10-18 20:27:03 -07001118}
1119
Tejun Heo8fc48982009-02-20 16:29:08 +09001120/**
1121 * map_kernel_range_noflush - map kernel VM area with the specified pages
1122 * @addr: start of the VM area to map
1123 * @size: size of the VM area to map
1124 * @prot: page protection flags to use
1125 * @pages: pages to map
1126 *
1127 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1128 * specify should have been allocated using get_vm_area() and its
1129 * friends.
1130 *
1131 * NOTE:
1132 * This function does NOT do any cache flushing. The caller is
1133 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1134 * before calling this function.
1135 *
1136 * RETURNS:
1137 * The number of pages mapped on success, -errno on failure.
1138 */
1139int map_kernel_range_noflush(unsigned long addr, unsigned long size,
1140 pgprot_t prot, struct page **pages)
1141{
1142 return vmap_page_range_noflush(addr, addr + size, prot, pages);
1143}
1144
1145/**
1146 * unmap_kernel_range_noflush - unmap kernel VM area
1147 * @addr: start of the VM area to unmap
1148 * @size: size of the VM area to unmap
1149 *
1150 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1151 * specify should have been allocated using get_vm_area() and its
1152 * friends.
1153 *
1154 * NOTE:
1155 * This function does NOT do any cache flushing. The caller is
1156 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1157 * before calling this function and flush_tlb_kernel_range() after.
1158 */
1159void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
1160{
1161 vunmap_page_range(addr, addr + size);
1162}
1163
1164/**
1165 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1166 * @addr: start of the VM area to unmap
1167 * @size: size of the VM area to unmap
1168 *
1169 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1170 * the unmapping and tlb after.
1171 */
Nick Piggindb64fe02008-10-18 20:27:03 -07001172void unmap_kernel_range(unsigned long addr, unsigned long size)
1173{
1174 unsigned long end = addr + size;
Tejun Heof6fcba72009-02-20 15:38:48 -08001175
1176 flush_cache_vunmap(addr, end);
Nick Piggindb64fe02008-10-18 20:27:03 -07001177 vunmap_page_range(addr, end);
1178 flush_tlb_kernel_range(addr, end);
1179}
1180
1181int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages)
1182{
1183 unsigned long addr = (unsigned long)area->addr;
1184 unsigned long end = addr + area->size - PAGE_SIZE;
1185 int err;
1186
1187 err = vmap_page_range(addr, end, prot, *pages);
1188 if (err > 0) {
1189 *pages += err;
1190 err = 0;
1191 }
1192
1193 return err;
1194}
1195EXPORT_SYMBOL_GPL(map_vm_area);
1196
1197/*** Old vmalloc interfaces ***/
1198DEFINE_RWLOCK(vmlist_lock);
1199struct vm_struct *vmlist;
1200
Tejun Heocf88c792009-08-14 15:00:52 +09001201static void insert_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
1202 unsigned long flags, void *caller)
1203{
1204 struct vm_struct *tmp, **p;
1205
1206 vm->flags = flags;
1207 vm->addr = (void *)va->va_start;
1208 vm->size = va->va_end - va->va_start;
1209 vm->caller = caller;
1210 va->private = vm;
1211 va->flags |= VM_VM_AREA;
1212
1213 write_lock(&vmlist_lock);
1214 for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
1215 if (tmp->addr >= vm->addr)
1216 break;
1217 }
1218 vm->next = *p;
1219 *p = vm;
1220 write_unlock(&vmlist_lock);
1221}
1222
Nick Piggindb64fe02008-10-18 20:27:03 -07001223static struct vm_struct *__get_vm_area_node(unsigned long size,
David Miller2dca6992009-09-21 12:22:34 -07001224 unsigned long align, unsigned long flags, unsigned long start,
1225 unsigned long end, int node, gfp_t gfp_mask, void *caller)
Nick Piggindb64fe02008-10-18 20:27:03 -07001226{
1227 static struct vmap_area *va;
1228 struct vm_struct *area;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229
Giridhar Pemmasani52fd24c2006-10-28 10:38:34 -07001230 BUG_ON(in_interrupt());
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231 if (flags & VM_IOREMAP) {
1232 int bit = fls(size);
1233
1234 if (bit > IOREMAP_MAX_ORDER)
1235 bit = IOREMAP_MAX_ORDER;
1236 else if (bit < PAGE_SHIFT)
1237 bit = PAGE_SHIFT;
1238
1239 align = 1ul << bit;
1240 }
Nick Piggindb64fe02008-10-18 20:27:03 -07001241
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242 size = PAGE_ALIGN(size);
OGAWA Hirofumi31be8302006-11-16 01:19:29 -08001243 if (unlikely(!size))
1244 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245
Tejun Heocf88c792009-08-14 15:00:52 +09001246 area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247 if (unlikely(!area))
1248 return NULL;
1249
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 /*
1251 * We always allocate a guard page.
1252 */
1253 size += PAGE_SIZE;
1254
Nick Piggindb64fe02008-10-18 20:27:03 -07001255 va = alloc_vmap_area(size, align, start, end, node, gfp_mask);
1256 if (IS_ERR(va)) {
1257 kfree(area);
1258 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001260
Tejun Heocf88c792009-08-14 15:00:52 +09001261 insert_vmalloc_vm(area, va, flags, caller);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 return area;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263}
1264
Christoph Lameter930fc452005-10-29 18:15:41 -07001265struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
1266 unsigned long start, unsigned long end)
1267{
David Miller2dca6992009-09-21 12:22:34 -07001268 return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL,
Christoph Lameter23016962008-04-28 02:12:42 -07001269 __builtin_return_address(0));
Christoph Lameter930fc452005-10-29 18:15:41 -07001270}
Rusty Russell5992b6d2007-07-19 01:49:21 -07001271EXPORT_SYMBOL_GPL(__get_vm_area);
Christoph Lameter930fc452005-10-29 18:15:41 -07001272
Benjamin Herrenschmidtc2968612009-02-18 14:48:12 -08001273struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
1274 unsigned long start, unsigned long end,
1275 void *caller)
1276{
David Miller2dca6992009-09-21 12:22:34 -07001277 return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL,
Benjamin Herrenschmidtc2968612009-02-18 14:48:12 -08001278 caller);
1279}
1280
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281/**
Simon Arlott183ff222007-10-20 01:27:18 +02001282 * get_vm_area - reserve a contiguous kernel virtual area
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283 * @size: size of the area
1284 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
1285 *
1286 * Search an area of @size in the kernel virtual mapping area,
1287 * and reserved it for out purposes. Returns the area descriptor
1288 * on success or %NULL on failure.
1289 */
1290struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
1291{
David Miller2dca6992009-09-21 12:22:34 -07001292 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
Christoph Lameter23016962008-04-28 02:12:42 -07001293 -1, GFP_KERNEL, __builtin_return_address(0));
1294}
1295
1296struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
1297 void *caller)
1298{
David Miller2dca6992009-09-21 12:22:34 -07001299 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
Christoph Lameter23016962008-04-28 02:12:42 -07001300 -1, GFP_KERNEL, caller);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301}
1302
Giridhar Pemmasani52fd24c2006-10-28 10:38:34 -07001303struct vm_struct *get_vm_area_node(unsigned long size, unsigned long flags,
1304 int node, gfp_t gfp_mask)
Christoph Lameter930fc452005-10-29 18:15:41 -07001305{
David Miller2dca6992009-09-21 12:22:34 -07001306 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1307 node, gfp_mask, __builtin_return_address(0));
Christoph Lameter930fc452005-10-29 18:15:41 -07001308}
1309
Nick Piggindb64fe02008-10-18 20:27:03 -07001310static struct vm_struct *find_vm_area(const void *addr)
Nick Piggin83342312006-06-23 02:03:20 -07001311{
Nick Piggindb64fe02008-10-18 20:27:03 -07001312 struct vmap_area *va;
Nick Piggin83342312006-06-23 02:03:20 -07001313
Nick Piggindb64fe02008-10-18 20:27:03 -07001314 va = find_vmap_area((unsigned long)addr);
1315 if (va && va->flags & VM_VM_AREA)
1316 return va->private;
Nick Piggin83342312006-06-23 02:03:20 -07001317
Andi Kleen7856dfe2005-05-20 14:27:57 -07001318 return NULL;
Andi Kleen7856dfe2005-05-20 14:27:57 -07001319}
1320
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321/**
Simon Arlott183ff222007-10-20 01:27:18 +02001322 * remove_vm_area - find and remove a continuous kernel virtual area
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 * @addr: base address
1324 *
1325 * Search for the kernel VM area starting at @addr, and remove it.
1326 * This function returns the found VM area, but using it is NOT safe
Andi Kleen7856dfe2005-05-20 14:27:57 -07001327 * on SMP machines, except for its size or flags.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 */
Christoph Lameterb3bdda02008-02-04 22:28:32 -08001329struct vm_struct *remove_vm_area(const void *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330{
Nick Piggindb64fe02008-10-18 20:27:03 -07001331 struct vmap_area *va;
1332
1333 va = find_vmap_area((unsigned long)addr);
1334 if (va && va->flags & VM_VM_AREA) {
1335 struct vm_struct *vm = va->private;
1336 struct vm_struct *tmp, **p;
KAMEZAWA Hiroyukidd32c272009-09-21 17:02:32 -07001337 /*
1338 * remove from list and disallow access to this vm_struct
1339 * before unmap. (address range confliction is maintained by
1340 * vmap.)
1341 */
Nick Piggindb64fe02008-10-18 20:27:03 -07001342 write_lock(&vmlist_lock);
1343 for (p = &vmlist; (tmp = *p) != vm; p = &tmp->next)
1344 ;
1345 *p = tmp->next;
1346 write_unlock(&vmlist_lock);
1347
KAMEZAWA Hiroyukidd32c272009-09-21 17:02:32 -07001348 vmap_debug_free_range(va->va_start, va->va_end);
1349 free_unmap_vmap_area(va);
1350 vm->size -= PAGE_SIZE;
1351
Nick Piggindb64fe02008-10-18 20:27:03 -07001352 return vm;
1353 }
1354 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355}
1356
Christoph Lameterb3bdda02008-02-04 22:28:32 -08001357static void __vunmap(const void *addr, int deallocate_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358{
1359 struct vm_struct *area;
1360
1361 if (!addr)
1362 return;
1363
1364 if ((PAGE_SIZE-1) & (unsigned long)addr) {
Arjan van de Ven4c8573e2008-07-25 19:45:37 -07001365 WARN(1, KERN_ERR "Trying to vfree() bad address (%p)\n", addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 return;
1367 }
1368
1369 area = remove_vm_area(addr);
1370 if (unlikely(!area)) {
Arjan van de Ven4c8573e2008-07-25 19:45:37 -07001371 WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373 return;
1374 }
1375
Ingo Molnar9a11b49a2006-07-03 00:24:33 -07001376 debug_check_no_locks_freed(addr, area->size);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001377 debug_check_no_obj_freed(addr, area->size);
Ingo Molnar9a11b49a2006-07-03 00:24:33 -07001378
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379 if (deallocate_pages) {
1380 int i;
1381
1382 for (i = 0; i < area->nr_pages; i++) {
Christoph Lameterbf53d6f2008-02-04 22:28:34 -08001383 struct page *page = area->pages[i];
1384
1385 BUG_ON(!page);
1386 __free_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001387 }
1388
Jan Kiszka8757d5f2006-07-14 00:23:56 -07001389 if (area->flags & VM_VPAGES)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001390 vfree(area->pages);
1391 else
1392 kfree(area->pages);
1393 }
1394
1395 kfree(area);
1396 return;
1397}
1398
1399/**
1400 * vfree - release memory allocated by vmalloc()
Linus Torvalds1da177e2005-04-16 15:20:36 -07001401 * @addr: memory base address
1402 *
Simon Arlott183ff222007-10-20 01:27:18 +02001403 * Free the virtually continuous memory area starting at @addr, as
Pekka Enberg80e93ef2005-09-09 13:10:16 -07001404 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
1405 * NULL, no operation is performed.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 *
Pekka Enberg80e93ef2005-09-09 13:10:16 -07001407 * Must not be called in interrupt context.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408 */
Christoph Lameterb3bdda02008-02-04 22:28:32 -08001409void vfree(const void *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410{
1411 BUG_ON(in_interrupt());
Catalin Marinas89219d32009-06-11 13:23:19 +01001412
1413 kmemleak_free(addr);
1414
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 __vunmap(addr, 1);
1416}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417EXPORT_SYMBOL(vfree);
1418
1419/**
1420 * vunmap - release virtual mapping obtained by vmap()
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 * @addr: memory base address
1422 *
1423 * Free the virtually contiguous memory area starting at @addr,
1424 * which was created from the page array passed to vmap().
1425 *
Pekka Enberg80e93ef2005-09-09 13:10:16 -07001426 * Must not be called in interrupt context.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427 */
Christoph Lameterb3bdda02008-02-04 22:28:32 -08001428void vunmap(const void *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429{
1430 BUG_ON(in_interrupt());
Peter Zijlstra34754b62009-02-25 16:04:03 +01001431 might_sleep();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432 __vunmap(addr, 0);
1433}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001434EXPORT_SYMBOL(vunmap);
1435
1436/**
1437 * vmap - map an array of pages into virtually contiguous space
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438 * @pages: array of page pointers
1439 * @count: number of pages to map
1440 * @flags: vm_area->flags
1441 * @prot: page protection for the mapping
1442 *
1443 * Maps @count pages from @pages into contiguous kernel virtual
1444 * space.
1445 */
1446void *vmap(struct page **pages, unsigned int count,
1447 unsigned long flags, pgprot_t prot)
1448{
1449 struct vm_struct *area;
1450
Peter Zijlstra34754b62009-02-25 16:04:03 +01001451 might_sleep();
1452
Jan Beulich44813742009-09-21 17:03:05 -07001453 if (count > totalram_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 return NULL;
1455
Christoph Lameter23016962008-04-28 02:12:42 -07001456 area = get_vm_area_caller((count << PAGE_SHIFT), flags,
1457 __builtin_return_address(0));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001458 if (!area)
1459 return NULL;
Christoph Lameter23016962008-04-28 02:12:42 -07001460
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461 if (map_vm_area(area, prot, &pages)) {
1462 vunmap(area->addr);
1463 return NULL;
1464 }
1465
1466 return area->addr;
1467}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468EXPORT_SYMBOL(vmap);
1469
David Miller2dca6992009-09-21 12:22:34 -07001470static void *__vmalloc_node(unsigned long size, unsigned long align,
1471 gfp_t gfp_mask, pgprot_t prot,
Nick Piggindb64fe02008-10-18 20:27:03 -07001472 int node, void *caller);
Adrian Bunke31d9eb2008-02-04 22:29:09 -08001473static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
Christoph Lameter23016962008-04-28 02:12:42 -07001474 pgprot_t prot, int node, void *caller)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475{
1476 struct page **pages;
1477 unsigned int nr_pages, array_size, i;
Jan Beulich976d6df2009-12-14 17:58:39 -08001478 gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479
1480 nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT;
1481 array_size = (nr_pages * sizeof(struct page *));
1482
1483 area->nr_pages = nr_pages;
1484 /* Please note that the recursion is strictly bounded. */
Jan Kiszka8757d5f2006-07-14 00:23:56 -07001485 if (array_size > PAGE_SIZE) {
Jan Beulich976d6df2009-12-14 17:58:39 -08001486 pages = __vmalloc_node(array_size, 1, nested_gfp|__GFP_HIGHMEM,
Christoph Lameter23016962008-04-28 02:12:42 -07001487 PAGE_KERNEL, node, caller);
Jan Kiszka8757d5f2006-07-14 00:23:56 -07001488 area->flags |= VM_VPAGES;
Andrew Morton286e1ea2006-10-17 00:09:57 -07001489 } else {
Jan Beulich976d6df2009-12-14 17:58:39 -08001490 pages = kmalloc_node(array_size, nested_gfp, node);
Andrew Morton286e1ea2006-10-17 00:09:57 -07001491 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 area->pages = pages;
Christoph Lameter23016962008-04-28 02:12:42 -07001493 area->caller = caller;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494 if (!area->pages) {
1495 remove_vm_area(area->addr);
1496 kfree(area);
1497 return NULL;
1498 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001499
1500 for (i = 0; i < area->nr_pages; i++) {
Christoph Lameterbf53d6f2008-02-04 22:28:34 -08001501 struct page *page;
1502
Christoph Lameter930fc452005-10-29 18:15:41 -07001503 if (node < 0)
Christoph Lameterbf53d6f2008-02-04 22:28:34 -08001504 page = alloc_page(gfp_mask);
Christoph Lameter930fc452005-10-29 18:15:41 -07001505 else
Christoph Lameterbf53d6f2008-02-04 22:28:34 -08001506 page = alloc_pages_node(node, gfp_mask, 0);
1507
1508 if (unlikely(!page)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509 /* Successfully allocated i pages, free them in __vunmap() */
1510 area->nr_pages = i;
1511 goto fail;
1512 }
Christoph Lameterbf53d6f2008-02-04 22:28:34 -08001513 area->pages[i] = page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514 }
1515
1516 if (map_vm_area(area, prot, &pages))
1517 goto fail;
1518 return area->addr;
1519
1520fail:
1521 vfree(area->addr);
1522 return NULL;
1523}
1524
Christoph Lameter930fc452005-10-29 18:15:41 -07001525void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask, pgprot_t prot)
1526{
Catalin Marinas89219d32009-06-11 13:23:19 +01001527 void *addr = __vmalloc_area_node(area, gfp_mask, prot, -1,
1528 __builtin_return_address(0));
1529
1530 /*
1531 * A ref_count = 3 is needed because the vm_struct and vmap_area
1532 * structures allocated in the __get_vm_area_node() function contain
1533 * references to the virtual address of the vmalloc'ed block.
1534 */
1535 kmemleak_alloc(addr, area->size - PAGE_SIZE, 3, gfp_mask);
1536
1537 return addr;
Christoph Lameter930fc452005-10-29 18:15:41 -07001538}
1539
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540/**
Christoph Lameter930fc452005-10-29 18:15:41 -07001541 * __vmalloc_node - allocate virtually contiguous memory
Linus Torvalds1da177e2005-04-16 15:20:36 -07001542 * @size: allocation size
David Miller2dca6992009-09-21 12:22:34 -07001543 * @align: desired alignment
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544 * @gfp_mask: flags for the page level allocator
1545 * @prot: protection mask for the allocated pages
Randy Dunlapd44e0782005-11-07 01:01:10 -08001546 * @node: node to use for allocation or -1
Randy Dunlapc85d1942008-05-01 04:34:48 -07001547 * @caller: caller's return address
Linus Torvalds1da177e2005-04-16 15:20:36 -07001548 *
1549 * Allocate enough pages to cover @size from the page level
1550 * allocator with @gfp_mask flags. Map them into contiguous
1551 * kernel virtual space, using a pagetable protection of @prot.
1552 */
David Miller2dca6992009-09-21 12:22:34 -07001553static void *__vmalloc_node(unsigned long size, unsigned long align,
1554 gfp_t gfp_mask, pgprot_t prot,
1555 int node, void *caller)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001556{
1557 struct vm_struct *area;
Catalin Marinas89219d32009-06-11 13:23:19 +01001558 void *addr;
1559 unsigned long real_size = size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001560
1561 size = PAGE_ALIGN(size);
Jan Beulich44813742009-09-21 17:03:05 -07001562 if (!size || (size >> PAGE_SHIFT) > totalram_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563 return NULL;
1564
David Miller2dca6992009-09-21 12:22:34 -07001565 area = __get_vm_area_node(size, align, VM_ALLOC, VMALLOC_START,
1566 VMALLOC_END, node, gfp_mask, caller);
Christoph Lameter23016962008-04-28 02:12:42 -07001567
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568 if (!area)
1569 return NULL;
1570
Catalin Marinas89219d32009-06-11 13:23:19 +01001571 addr = __vmalloc_area_node(area, gfp_mask, prot, node, caller);
1572
1573 /*
1574 * A ref_count = 3 is needed because the vm_struct and vmap_area
1575 * structures allocated in the __get_vm_area_node() function contain
1576 * references to the virtual address of the vmalloc'ed block.
1577 */
1578 kmemleak_alloc(addr, real_size, 3, gfp_mask);
1579
1580 return addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581}
1582
Christoph Lameter930fc452005-10-29 18:15:41 -07001583void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
1584{
David Miller2dca6992009-09-21 12:22:34 -07001585 return __vmalloc_node(size, 1, gfp_mask, prot, -1,
Christoph Lameter23016962008-04-28 02:12:42 -07001586 __builtin_return_address(0));
Christoph Lameter930fc452005-10-29 18:15:41 -07001587}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588EXPORT_SYMBOL(__vmalloc);
1589
1590/**
1591 * vmalloc - allocate virtually contiguous memory
Linus Torvalds1da177e2005-04-16 15:20:36 -07001592 * @size: allocation size
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 * Allocate enough pages to cover @size from the page level
1594 * allocator and map them into contiguous kernel virtual space.
1595 *
Michael Opdenackerc1c88972006-10-03 23:21:02 +02001596 * For tight control over page level allocator and protection flags
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 * use __vmalloc() instead.
1598 */
1599void *vmalloc(unsigned long size)
1600{
David Miller2dca6992009-09-21 12:22:34 -07001601 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL,
Christoph Lameter23016962008-04-28 02:12:42 -07001602 -1, __builtin_return_address(0));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604EXPORT_SYMBOL(vmalloc);
1605
Christoph Lameter930fc452005-10-29 18:15:41 -07001606/**
Rolf Eike Beeread04082006-09-27 01:50:13 -07001607 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
1608 * @size: allocation size
Nick Piggin83342312006-06-23 02:03:20 -07001609 *
Rolf Eike Beeread04082006-09-27 01:50:13 -07001610 * The resulting memory area is zeroed so it can be mapped to userspace
1611 * without leaking data.
Nick Piggin83342312006-06-23 02:03:20 -07001612 */
1613void *vmalloc_user(unsigned long size)
1614{
1615 struct vm_struct *area;
1616 void *ret;
1617
David Miller2dca6992009-09-21 12:22:34 -07001618 ret = __vmalloc_node(size, SHMLBA,
1619 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
Glauber Costa84877842009-01-06 14:39:19 -08001620 PAGE_KERNEL, -1, __builtin_return_address(0));
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001621 if (ret) {
Nick Piggindb64fe02008-10-18 20:27:03 -07001622 area = find_vm_area(ret);
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001623 area->flags |= VM_USERMAP;
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001624 }
Nick Piggin83342312006-06-23 02:03:20 -07001625 return ret;
1626}
1627EXPORT_SYMBOL(vmalloc_user);
1628
1629/**
Christoph Lameter930fc452005-10-29 18:15:41 -07001630 * vmalloc_node - allocate memory on a specific node
Christoph Lameter930fc452005-10-29 18:15:41 -07001631 * @size: allocation size
Randy Dunlapd44e0782005-11-07 01:01:10 -08001632 * @node: numa node
Christoph Lameter930fc452005-10-29 18:15:41 -07001633 *
1634 * Allocate enough pages to cover @size from the page level
1635 * allocator and map them into contiguous kernel virtual space.
1636 *
Michael Opdenackerc1c88972006-10-03 23:21:02 +02001637 * For tight control over page level allocator and protection flags
Christoph Lameter930fc452005-10-29 18:15:41 -07001638 * use __vmalloc() instead.
1639 */
1640void *vmalloc_node(unsigned long size, int node)
1641{
David Miller2dca6992009-09-21 12:22:34 -07001642 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL,
Christoph Lameter23016962008-04-28 02:12:42 -07001643 node, __builtin_return_address(0));
Christoph Lameter930fc452005-10-29 18:15:41 -07001644}
1645EXPORT_SYMBOL(vmalloc_node);
1646
Pavel Pisa4dc3b162005-05-01 08:59:25 -07001647#ifndef PAGE_KERNEL_EXEC
1648# define PAGE_KERNEL_EXEC PAGE_KERNEL
1649#endif
1650
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651/**
1652 * vmalloc_exec - allocate virtually contiguous, executable memory
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 * @size: allocation size
1654 *
1655 * Kernel-internal function to allocate enough pages to cover @size
1656 * the page level allocator and map them into contiguous and
1657 * executable kernel virtual space.
1658 *
Michael Opdenackerc1c88972006-10-03 23:21:02 +02001659 * For tight control over page level allocator and protection flags
Linus Torvalds1da177e2005-04-16 15:20:36 -07001660 * use __vmalloc() instead.
1661 */
1662
Linus Torvalds1da177e2005-04-16 15:20:36 -07001663void *vmalloc_exec(unsigned long size)
1664{
David Miller2dca6992009-09-21 12:22:34 -07001665 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
Glauber Costa84877842009-01-06 14:39:19 -08001666 -1, __builtin_return_address(0));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667}
1668
Andi Kleen0d08e0d2007-05-02 19:27:12 +02001669#if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
Benjamin Herrenschmidt7ac674f2007-07-19 01:49:10 -07001670#define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
Andi Kleen0d08e0d2007-05-02 19:27:12 +02001671#elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
Benjamin Herrenschmidt7ac674f2007-07-19 01:49:10 -07001672#define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
Andi Kleen0d08e0d2007-05-02 19:27:12 +02001673#else
1674#define GFP_VMALLOC32 GFP_KERNEL
1675#endif
1676
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677/**
1678 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001679 * @size: allocation size
1680 *
1681 * Allocate enough 32bit PA addressable pages to cover @size from the
1682 * page level allocator and map them into contiguous kernel virtual space.
1683 */
1684void *vmalloc_32(unsigned long size)
1685{
David Miller2dca6992009-09-21 12:22:34 -07001686 return __vmalloc_node(size, 1, GFP_VMALLOC32, PAGE_KERNEL,
Glauber Costa84877842009-01-06 14:39:19 -08001687 -1, __builtin_return_address(0));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001689EXPORT_SYMBOL(vmalloc_32);
1690
Nick Piggin83342312006-06-23 02:03:20 -07001691/**
Rolf Eike Beeread04082006-09-27 01:50:13 -07001692 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
Nick Piggin83342312006-06-23 02:03:20 -07001693 * @size: allocation size
Rolf Eike Beeread04082006-09-27 01:50:13 -07001694 *
1695 * The resulting memory area is 32bit addressable and zeroed so it can be
1696 * mapped to userspace without leaking data.
Nick Piggin83342312006-06-23 02:03:20 -07001697 */
1698void *vmalloc_32_user(unsigned long size)
1699{
1700 struct vm_struct *area;
1701 void *ret;
1702
David Miller2dca6992009-09-21 12:22:34 -07001703 ret = __vmalloc_node(size, 1, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
Glauber Costa84877842009-01-06 14:39:19 -08001704 -1, __builtin_return_address(0));
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001705 if (ret) {
Nick Piggindb64fe02008-10-18 20:27:03 -07001706 area = find_vm_area(ret);
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001707 area->flags |= VM_USERMAP;
Eric Dumazet2b4ac442006-11-10 12:27:48 -08001708 }
Nick Piggin83342312006-06-23 02:03:20 -07001709 return ret;
1710}
1711EXPORT_SYMBOL(vmalloc_32_user);
1712
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001713/*
1714 * small helper routine , copy contents to buf from addr.
1715 * If the page is not present, fill zero.
1716 */
1717
1718static int aligned_vread(char *buf, char *addr, unsigned long count)
1719{
1720 struct page *p;
1721 int copied = 0;
1722
1723 while (count) {
1724 unsigned long offset, length;
1725
1726 offset = (unsigned long)addr & ~PAGE_MASK;
1727 length = PAGE_SIZE - offset;
1728 if (length > count)
1729 length = count;
1730 p = vmalloc_to_page(addr);
1731 /*
1732 * To do safe access to this _mapped_ area, we need
1733 * lock. But adding lock here means that we need to add
1734 * overhead of vmalloc()/vfree() calles for this _debug_
1735 * interface, rarely used. Instead of that, we'll use
1736 * kmap() and get small overhead in this access function.
1737 */
1738 if (p) {
1739 /*
1740 * we can expect USER0 is not used (see vread/vwrite's
1741 * function description)
1742 */
1743 void *map = kmap_atomic(p, KM_USER0);
1744 memcpy(buf, map + offset, length);
1745 kunmap_atomic(map, KM_USER0);
1746 } else
1747 memset(buf, 0, length);
1748
1749 addr += length;
1750 buf += length;
1751 copied += length;
1752 count -= length;
1753 }
1754 return copied;
1755}
1756
1757static int aligned_vwrite(char *buf, char *addr, unsigned long count)
1758{
1759 struct page *p;
1760 int copied = 0;
1761
1762 while (count) {
1763 unsigned long offset, length;
1764
1765 offset = (unsigned long)addr & ~PAGE_MASK;
1766 length = PAGE_SIZE - offset;
1767 if (length > count)
1768 length = count;
1769 p = vmalloc_to_page(addr);
1770 /*
1771 * To do safe access to this _mapped_ area, we need
1772 * lock. But adding lock here means that we need to add
1773 * overhead of vmalloc()/vfree() calles for this _debug_
1774 * interface, rarely used. Instead of that, we'll use
1775 * kmap() and get small overhead in this access function.
1776 */
1777 if (p) {
1778 /*
1779 * we can expect USER0 is not used (see vread/vwrite's
1780 * function description)
1781 */
1782 void *map = kmap_atomic(p, KM_USER0);
1783 memcpy(map + offset, buf, length);
1784 kunmap_atomic(map, KM_USER0);
1785 }
1786 addr += length;
1787 buf += length;
1788 copied += length;
1789 count -= length;
1790 }
1791 return copied;
1792}
1793
1794/**
1795 * vread() - read vmalloc area in a safe way.
1796 * @buf: buffer for reading data
1797 * @addr: vm address.
1798 * @count: number of bytes to be read.
1799 *
1800 * Returns # of bytes which addr and buf should be increased.
1801 * (same number to @count). Returns 0 if [addr...addr+count) doesn't
1802 * includes any intersect with alive vmalloc area.
1803 *
1804 * This function checks that addr is a valid vmalloc'ed area, and
1805 * copy data from that area to a given buffer. If the given memory range
1806 * of [addr...addr+count) includes some valid address, data is copied to
1807 * proper area of @buf. If there are memory holes, they'll be zero-filled.
1808 * IOREMAP area is treated as memory hole and no copy is done.
1809 *
1810 * If [addr...addr+count) doesn't includes any intersects with alive
1811 * vm_struct area, returns 0.
1812 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1813 * the caller should guarantee KM_USER0 is not used.
1814 *
1815 * Note: In usual ops, vread() is never necessary because the caller
1816 * should know vmalloc() area is valid and can use memcpy().
1817 * This is for routines which have to access vmalloc area without
1818 * any informaion, as /dev/kmem.
1819 *
1820 */
1821
Linus Torvalds1da177e2005-04-16 15:20:36 -07001822long vread(char *buf, char *addr, unsigned long count)
1823{
1824 struct vm_struct *tmp;
1825 char *vaddr, *buf_start = buf;
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001826 unsigned long buflen = count;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001827 unsigned long n;
1828
1829 /* Don't allow overflow */
1830 if ((unsigned long) addr + count < count)
1831 count = -(unsigned long) addr;
1832
1833 read_lock(&vmlist_lock);
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001834 for (tmp = vmlist; count && tmp; tmp = tmp->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001835 vaddr = (char *) tmp->addr;
1836 if (addr >= vaddr + tmp->size - PAGE_SIZE)
1837 continue;
1838 while (addr < vaddr) {
1839 if (count == 0)
1840 goto finished;
1841 *buf = '\0';
1842 buf++;
1843 addr++;
1844 count--;
1845 }
1846 n = vaddr + tmp->size - PAGE_SIZE - addr;
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001847 if (n > count)
1848 n = count;
1849 if (!(tmp->flags & VM_IOREMAP))
1850 aligned_vread(buf, addr, n);
1851 else /* IOREMAP area is treated as memory hole */
1852 memset(buf, 0, n);
1853 buf += n;
1854 addr += n;
1855 count -= n;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001856 }
1857finished:
1858 read_unlock(&vmlist_lock);
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001859
1860 if (buf == buf_start)
1861 return 0;
1862 /* zero-fill memory holes */
1863 if (buf != buf_start + buflen)
1864 memset(buf, 0, buflen - (buf - buf_start));
1865
1866 return buflen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001867}
1868
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001869/**
1870 * vwrite() - write vmalloc area in a safe way.
1871 * @buf: buffer for source data
1872 * @addr: vm address.
1873 * @count: number of bytes to be read.
1874 *
1875 * Returns # of bytes which addr and buf should be incresed.
1876 * (same number to @count).
1877 * If [addr...addr+count) doesn't includes any intersect with valid
1878 * vmalloc area, returns 0.
1879 *
1880 * This function checks that addr is a valid vmalloc'ed area, and
1881 * copy data from a buffer to the given addr. If specified range of
1882 * [addr...addr+count) includes some valid address, data is copied from
1883 * proper area of @buf. If there are memory holes, no copy to hole.
1884 * IOREMAP area is treated as memory hole and no copy is done.
1885 *
1886 * If [addr...addr+count) doesn't includes any intersects with alive
1887 * vm_struct area, returns 0.
1888 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1889 * the caller should guarantee KM_USER0 is not used.
1890 *
1891 * Note: In usual ops, vwrite() is never necessary because the caller
1892 * should know vmalloc() area is valid and can use memcpy().
1893 * This is for routines which have to access vmalloc area without
1894 * any informaion, as /dev/kmem.
1895 *
1896 * The caller should guarantee KM_USER1 is not used.
1897 */
1898
Linus Torvalds1da177e2005-04-16 15:20:36 -07001899long vwrite(char *buf, char *addr, unsigned long count)
1900{
1901 struct vm_struct *tmp;
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001902 char *vaddr;
1903 unsigned long n, buflen;
1904 int copied = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001905
1906 /* Don't allow overflow */
1907 if ((unsigned long) addr + count < count)
1908 count = -(unsigned long) addr;
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001909 buflen = count;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001910
1911 read_lock(&vmlist_lock);
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001912 for (tmp = vmlist; count && tmp; tmp = tmp->next) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001913 vaddr = (char *) tmp->addr;
1914 if (addr >= vaddr + tmp->size - PAGE_SIZE)
1915 continue;
1916 while (addr < vaddr) {
1917 if (count == 0)
1918 goto finished;
1919 buf++;
1920 addr++;
1921 count--;
1922 }
1923 n = vaddr + tmp->size - PAGE_SIZE - addr;
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001924 if (n > count)
1925 n = count;
1926 if (!(tmp->flags & VM_IOREMAP)) {
1927 aligned_vwrite(buf, addr, n);
1928 copied++;
1929 }
1930 buf += n;
1931 addr += n;
1932 count -= n;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001933 }
1934finished:
1935 read_unlock(&vmlist_lock);
KAMEZAWA Hiroyukid0107eb2009-09-21 17:02:34 -07001936 if (!copied)
1937 return 0;
1938 return buflen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939}
Nick Piggin83342312006-06-23 02:03:20 -07001940
1941/**
1942 * remap_vmalloc_range - map vmalloc pages to userspace
Nick Piggin83342312006-06-23 02:03:20 -07001943 * @vma: vma to cover (map full range of vma)
1944 * @addr: vmalloc memory
1945 * @pgoff: number of pages into addr before first page to map
Randy Dunlap76824862008-03-19 17:00:40 -07001946 *
1947 * Returns: 0 for success, -Exxx on failure
Nick Piggin83342312006-06-23 02:03:20 -07001948 *
1949 * This function checks that addr is a valid vmalloc'ed area, and
1950 * that it is big enough to cover the vma. Will return failure if
1951 * that criteria isn't met.
1952 *
Robert P. J. Day72fd4a32007-02-10 01:45:59 -08001953 * Similar to remap_pfn_range() (see mm/memory.c)
Nick Piggin83342312006-06-23 02:03:20 -07001954 */
1955int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
1956 unsigned long pgoff)
1957{
1958 struct vm_struct *area;
1959 unsigned long uaddr = vma->vm_start;
1960 unsigned long usize = vma->vm_end - vma->vm_start;
Nick Piggin83342312006-06-23 02:03:20 -07001961
1962 if ((PAGE_SIZE-1) & (unsigned long)addr)
1963 return -EINVAL;
1964
Nick Piggindb64fe02008-10-18 20:27:03 -07001965 area = find_vm_area(addr);
Nick Piggin83342312006-06-23 02:03:20 -07001966 if (!area)
Nick Piggindb64fe02008-10-18 20:27:03 -07001967 return -EINVAL;
Nick Piggin83342312006-06-23 02:03:20 -07001968
1969 if (!(area->flags & VM_USERMAP))
Nick Piggindb64fe02008-10-18 20:27:03 -07001970 return -EINVAL;
Nick Piggin83342312006-06-23 02:03:20 -07001971
1972 if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE)
Nick Piggindb64fe02008-10-18 20:27:03 -07001973 return -EINVAL;
Nick Piggin83342312006-06-23 02:03:20 -07001974
1975 addr += pgoff << PAGE_SHIFT;
1976 do {
1977 struct page *page = vmalloc_to_page(addr);
Nick Piggindb64fe02008-10-18 20:27:03 -07001978 int ret;
1979
Nick Piggin83342312006-06-23 02:03:20 -07001980 ret = vm_insert_page(vma, uaddr, page);
1981 if (ret)
1982 return ret;
1983
1984 uaddr += PAGE_SIZE;
1985 addr += PAGE_SIZE;
1986 usize -= PAGE_SIZE;
1987 } while (usize > 0);
1988
1989 /* Prevent "things" like memory migration? VM_flags need a cleanup... */
1990 vma->vm_flags |= VM_RESERVED;
1991
Nick Piggindb64fe02008-10-18 20:27:03 -07001992 return 0;
Nick Piggin83342312006-06-23 02:03:20 -07001993}
1994EXPORT_SYMBOL(remap_vmalloc_range);
1995
Christoph Hellwig1eeb66a2007-05-08 00:27:03 -07001996/*
1997 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
1998 * have one.
1999 */
2000void __attribute__((weak)) vmalloc_sync_all(void)
2001{
2002}
Jeremy Fitzhardinge5f4352f2007-07-17 18:37:04 -07002003
2004
Martin Schwidefsky2f569af2008-02-08 04:22:04 -08002005static int f(pte_t *pte, pgtable_t table, unsigned long addr, void *data)
Jeremy Fitzhardinge5f4352f2007-07-17 18:37:04 -07002006{
2007 /* apply_to_page_range() does all the hard work. */
2008 return 0;
2009}
2010
2011/**
2012 * alloc_vm_area - allocate a range of kernel address space
2013 * @size: size of the area
Randy Dunlap76824862008-03-19 17:00:40 -07002014 *
2015 * Returns: NULL on failure, vm_struct on success
Jeremy Fitzhardinge5f4352f2007-07-17 18:37:04 -07002016 *
2017 * This function reserves a range of kernel address space, and
2018 * allocates pagetables to map that range. No actual mappings
2019 * are created. If the kernel address space is not shared
2020 * between processes, it syncs the pagetable across all
2021 * processes.
2022 */
2023struct vm_struct *alloc_vm_area(size_t size)
2024{
2025 struct vm_struct *area;
2026
Christoph Lameter23016962008-04-28 02:12:42 -07002027 area = get_vm_area_caller(size, VM_IOREMAP,
2028 __builtin_return_address(0));
Jeremy Fitzhardinge5f4352f2007-07-17 18:37:04 -07002029 if (area == NULL)
2030 return NULL;
2031
2032 /*
2033 * This ensures that page tables are constructed for this region
2034 * of kernel virtual address space and mapped into init_mm.
2035 */
2036 if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
2037 area->size, f, NULL)) {
2038 free_vm_area(area);
2039 return NULL;
2040 }
2041
2042 /* Make sure the pagetables are constructed in process kernel
2043 mappings */
2044 vmalloc_sync_all();
2045
2046 return area;
2047}
2048EXPORT_SYMBOL_GPL(alloc_vm_area);
2049
2050void free_vm_area(struct vm_struct *area)
2051{
2052 struct vm_struct *ret;
2053 ret = remove_vm_area(area->addr);
2054 BUG_ON(ret != area);
2055 kfree(area);
2056}
2057EXPORT_SYMBOL_GPL(free_vm_area);
Christoph Lametera10aa572008-04-28 02:12:40 -07002058
Tejun Heoca23e402009-08-14 15:00:52 +09002059static struct vmap_area *node_to_va(struct rb_node *n)
2060{
2061 return n ? rb_entry(n, struct vmap_area, rb_node) : NULL;
2062}
2063
2064/**
2065 * pvm_find_next_prev - find the next and prev vmap_area surrounding @end
2066 * @end: target address
2067 * @pnext: out arg for the next vmap_area
2068 * @pprev: out arg for the previous vmap_area
2069 *
2070 * Returns: %true if either or both of next and prev are found,
2071 * %false if no vmap_area exists
2072 *
2073 * Find vmap_areas end addresses of which enclose @end. ie. if not
2074 * NULL, *pnext->va_end > @end and *pprev->va_end <= @end.
2075 */
2076static bool pvm_find_next_prev(unsigned long end,
2077 struct vmap_area **pnext,
2078 struct vmap_area **pprev)
2079{
2080 struct rb_node *n = vmap_area_root.rb_node;
2081 struct vmap_area *va = NULL;
2082
2083 while (n) {
2084 va = rb_entry(n, struct vmap_area, rb_node);
2085 if (end < va->va_end)
2086 n = n->rb_left;
2087 else if (end > va->va_end)
2088 n = n->rb_right;
2089 else
2090 break;
2091 }
2092
2093 if (!va)
2094 return false;
2095
2096 if (va->va_end > end) {
2097 *pnext = va;
2098 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2099 } else {
2100 *pprev = va;
2101 *pnext = node_to_va(rb_next(&(*pprev)->rb_node));
2102 }
2103 return true;
2104}
2105
2106/**
2107 * pvm_determine_end - find the highest aligned address between two vmap_areas
2108 * @pnext: in/out arg for the next vmap_area
2109 * @pprev: in/out arg for the previous vmap_area
2110 * @align: alignment
2111 *
2112 * Returns: determined end address
2113 *
2114 * Find the highest aligned address between *@pnext and *@pprev below
2115 * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned
2116 * down address is between the end addresses of the two vmap_areas.
2117 *
2118 * Please note that the address returned by this function may fall
2119 * inside *@pnext vmap_area. The caller is responsible for checking
2120 * that.
2121 */
2122static unsigned long pvm_determine_end(struct vmap_area **pnext,
2123 struct vmap_area **pprev,
2124 unsigned long align)
2125{
2126 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2127 unsigned long addr;
2128
2129 if (*pnext)
2130 addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end);
2131 else
2132 addr = vmalloc_end;
2133
2134 while (*pprev && (*pprev)->va_end > addr) {
2135 *pnext = *pprev;
2136 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2137 }
2138
2139 return addr;
2140}
2141
2142/**
2143 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
2144 * @offsets: array containing offset of each area
2145 * @sizes: array containing size of each area
2146 * @nr_vms: the number of areas to allocate
2147 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
2148 * @gfp_mask: allocation mask
2149 *
2150 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
2151 * vm_structs on success, %NULL on failure
2152 *
2153 * Percpu allocator wants to use congruent vm areas so that it can
2154 * maintain the offsets among percpu areas. This function allocates
2155 * congruent vmalloc areas for it. These areas tend to be scattered
2156 * pretty far, distance between two areas easily going up to
2157 * gigabytes. To avoid interacting with regular vmallocs, these areas
2158 * are allocated from top.
2159 *
2160 * Despite its complicated look, this allocator is rather simple. It
2161 * does everything top-down and scans areas from the end looking for
2162 * matching slot. While scanning, if any of the areas overlaps with
2163 * existing vmap_area, the base address is pulled down to fit the
2164 * area. Scanning is repeated till all the areas fit and then all
2165 * necessary data structres are inserted and the result is returned.
2166 */
2167struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
2168 const size_t *sizes, int nr_vms,
2169 size_t align, gfp_t gfp_mask)
2170{
2171 const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
2172 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2173 struct vmap_area **vas, *prev, *next;
2174 struct vm_struct **vms;
2175 int area, area2, last_area, term_area;
2176 unsigned long base, start, end, last_end;
2177 bool purged = false;
2178
2179 gfp_mask &= GFP_RECLAIM_MASK;
2180
2181 /* verify parameters and allocate data structures */
2182 BUG_ON(align & ~PAGE_MASK || !is_power_of_2(align));
2183 for (last_area = 0, area = 0; area < nr_vms; area++) {
2184 start = offsets[area];
2185 end = start + sizes[area];
2186
2187 /* is everything aligned properly? */
2188 BUG_ON(!IS_ALIGNED(offsets[area], align));
2189 BUG_ON(!IS_ALIGNED(sizes[area], align));
2190
2191 /* detect the area with the highest address */
2192 if (start > offsets[last_area])
2193 last_area = area;
2194
2195 for (area2 = 0; area2 < nr_vms; area2++) {
2196 unsigned long start2 = offsets[area2];
2197 unsigned long end2 = start2 + sizes[area2];
2198
2199 if (area2 == area)
2200 continue;
2201
2202 BUG_ON(start2 >= start && start2 < end);
2203 BUG_ON(end2 <= end && end2 > start);
2204 }
2205 }
2206 last_end = offsets[last_area] + sizes[last_area];
2207
2208 if (vmalloc_end - vmalloc_start < last_end) {
2209 WARN_ON(true);
2210 return NULL;
2211 }
2212
2213 vms = kzalloc(sizeof(vms[0]) * nr_vms, gfp_mask);
2214 vas = kzalloc(sizeof(vas[0]) * nr_vms, gfp_mask);
2215 if (!vas || !vms)
2216 goto err_free;
2217
2218 for (area = 0; area < nr_vms; area++) {
2219 vas[area] = kzalloc(sizeof(struct vmap_area), gfp_mask);
2220 vms[area] = kzalloc(sizeof(struct vm_struct), gfp_mask);
2221 if (!vas[area] || !vms[area])
2222 goto err_free;
2223 }
2224retry:
2225 spin_lock(&vmap_area_lock);
2226
2227 /* start scanning - we scan from the top, begin with the last area */
2228 area = term_area = last_area;
2229 start = offsets[area];
2230 end = start + sizes[area];
2231
2232 if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) {
2233 base = vmalloc_end - last_end;
2234 goto found;
2235 }
2236 base = pvm_determine_end(&next, &prev, align) - end;
2237
2238 while (true) {
2239 BUG_ON(next && next->va_end <= base + end);
2240 BUG_ON(prev && prev->va_end > base + end);
2241
2242 /*
2243 * base might have underflowed, add last_end before
2244 * comparing.
2245 */
2246 if (base + last_end < vmalloc_start + last_end) {
2247 spin_unlock(&vmap_area_lock);
2248 if (!purged) {
2249 purge_vmap_area_lazy();
2250 purged = true;
2251 goto retry;
2252 }
2253 goto err_free;
2254 }
2255
2256 /*
2257 * If next overlaps, move base downwards so that it's
2258 * right below next and then recheck.
2259 */
2260 if (next && next->va_start < base + end) {
2261 base = pvm_determine_end(&next, &prev, align) - end;
2262 term_area = area;
2263 continue;
2264 }
2265
2266 /*
2267 * If prev overlaps, shift down next and prev and move
2268 * base so that it's right below new next and then
2269 * recheck.
2270 */
2271 if (prev && prev->va_end > base + start) {
2272 next = prev;
2273 prev = node_to_va(rb_prev(&next->rb_node));
2274 base = pvm_determine_end(&next, &prev, align) - end;
2275 term_area = area;
2276 continue;
2277 }
2278
2279 /*
2280 * This area fits, move on to the previous one. If
2281 * the previous one is the terminal one, we're done.
2282 */
2283 area = (area + nr_vms - 1) % nr_vms;
2284 if (area == term_area)
2285 break;
2286 start = offsets[area];
2287 end = start + sizes[area];
2288 pvm_find_next_prev(base + end, &next, &prev);
2289 }
2290found:
2291 /* we've found a fitting base, insert all va's */
2292 for (area = 0; area < nr_vms; area++) {
2293 struct vmap_area *va = vas[area];
2294
2295 va->va_start = base + offsets[area];
2296 va->va_end = va->va_start + sizes[area];
2297 __insert_vmap_area(va);
2298 }
2299
2300 vmap_area_pcpu_hole = base + offsets[last_area];
2301
2302 spin_unlock(&vmap_area_lock);
2303
2304 /* insert all vm's */
2305 for (area = 0; area < nr_vms; area++)
2306 insert_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
2307 pcpu_get_vm_areas);
2308
2309 kfree(vas);
2310 return vms;
2311
2312err_free:
2313 for (area = 0; area < nr_vms; area++) {
2314 if (vas)
2315 kfree(vas[area]);
2316 if (vms)
2317 kfree(vms[area]);
2318 }
2319 kfree(vas);
2320 kfree(vms);
2321 return NULL;
2322}
2323
2324/**
2325 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
2326 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
2327 * @nr_vms: the number of allocated areas
2328 *
2329 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
2330 */
2331void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
2332{
2333 int i;
2334
2335 for (i = 0; i < nr_vms; i++)
2336 free_vm_area(vms[i]);
2337 kfree(vms);
2338}
Christoph Lametera10aa572008-04-28 02:12:40 -07002339
2340#ifdef CONFIG_PROC_FS
2341static void *s_start(struct seq_file *m, loff_t *pos)
2342{
2343 loff_t n = *pos;
2344 struct vm_struct *v;
2345
2346 read_lock(&vmlist_lock);
2347 v = vmlist;
2348 while (n > 0 && v) {
2349 n--;
2350 v = v->next;
2351 }
2352 if (!n)
2353 return v;
2354
2355 return NULL;
2356
2357}
2358
2359static void *s_next(struct seq_file *m, void *p, loff_t *pos)
2360{
2361 struct vm_struct *v = p;
2362
2363 ++*pos;
2364 return v->next;
2365}
2366
2367static void s_stop(struct seq_file *m, void *p)
2368{
2369 read_unlock(&vmlist_lock);
2370}
2371
Eric Dumazeta47a1262008-07-23 21:27:38 -07002372static void show_numa_info(struct seq_file *m, struct vm_struct *v)
2373{
2374 if (NUMA_BUILD) {
2375 unsigned int nr, *counters = m->private;
2376
2377 if (!counters)
2378 return;
2379
2380 memset(counters, 0, nr_node_ids * sizeof(unsigned int));
2381
2382 for (nr = 0; nr < v->nr_pages; nr++)
2383 counters[page_to_nid(v->pages[nr])]++;
2384
2385 for_each_node_state(nr, N_HIGH_MEMORY)
2386 if (counters[nr])
2387 seq_printf(m, " N%u=%u", nr, counters[nr]);
2388 }
2389}
2390
Christoph Lametera10aa572008-04-28 02:12:40 -07002391static int s_show(struct seq_file *m, void *p)
2392{
2393 struct vm_struct *v = p;
2394
2395 seq_printf(m, "0x%p-0x%p %7ld",
2396 v->addr, v->addr + v->size, v->size);
2397
Christoph Lameter23016962008-04-28 02:12:42 -07002398 if (v->caller) {
Hugh Dickins9c246242008-12-09 13:14:27 -08002399 char buff[KSYM_SYMBOL_LEN];
Christoph Lameter23016962008-04-28 02:12:42 -07002400
2401 seq_putc(m, ' ');
2402 sprint_symbol(buff, (unsigned long)v->caller);
2403 seq_puts(m, buff);
2404 }
2405
Christoph Lametera10aa572008-04-28 02:12:40 -07002406 if (v->nr_pages)
2407 seq_printf(m, " pages=%d", v->nr_pages);
2408
2409 if (v->phys_addr)
Kenji Kaneshigeffa71f32010-06-18 12:22:40 +09002410 seq_printf(m, " phys=%llx", (unsigned long long)v->phys_addr);
Christoph Lametera10aa572008-04-28 02:12:40 -07002411
2412 if (v->flags & VM_IOREMAP)
2413 seq_printf(m, " ioremap");
2414
2415 if (v->flags & VM_ALLOC)
2416 seq_printf(m, " vmalloc");
2417
2418 if (v->flags & VM_MAP)
2419 seq_printf(m, " vmap");
2420
2421 if (v->flags & VM_USERMAP)
2422 seq_printf(m, " user");
2423
2424 if (v->flags & VM_VPAGES)
2425 seq_printf(m, " vpages");
2426
Eric Dumazeta47a1262008-07-23 21:27:38 -07002427 show_numa_info(m, v);
Christoph Lametera10aa572008-04-28 02:12:40 -07002428 seq_putc(m, '\n');
2429 return 0;
2430}
2431
Alexey Dobriyan5f6a6a92008-10-06 03:50:47 +04002432static const struct seq_operations vmalloc_op = {
Christoph Lametera10aa572008-04-28 02:12:40 -07002433 .start = s_start,
2434 .next = s_next,
2435 .stop = s_stop,
2436 .show = s_show,
2437};
Alexey Dobriyan5f6a6a92008-10-06 03:50:47 +04002438
2439static int vmalloc_open(struct inode *inode, struct file *file)
2440{
2441 unsigned int *ptr = NULL;
2442 int ret;
2443
Kulikov Vasiliy51980ac2010-08-09 17:19:58 -07002444 if (NUMA_BUILD) {
Alexey Dobriyan5f6a6a92008-10-06 03:50:47 +04002445 ptr = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL);
Kulikov Vasiliy51980ac2010-08-09 17:19:58 -07002446 if (ptr == NULL)
2447 return -ENOMEM;
2448 }
Alexey Dobriyan5f6a6a92008-10-06 03:50:47 +04002449 ret = seq_open(file, &vmalloc_op);
2450 if (!ret) {
2451 struct seq_file *m = file->private_data;
2452 m->private = ptr;
2453 } else
2454 kfree(ptr);
2455 return ret;
2456}
2457
2458static const struct file_operations proc_vmalloc_operations = {
2459 .open = vmalloc_open,
2460 .read = seq_read,
2461 .llseek = seq_lseek,
2462 .release = seq_release_private,
2463};
2464
2465static int __init proc_vmalloc_init(void)
2466{
2467 proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
2468 return 0;
2469}
2470module_init(proc_vmalloc_init);
Christoph Lametera10aa572008-04-28 02:12:40 -07002471#endif
2472