Merge 2.6.38-rc5 into usb-next
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / mm / vmalloc.c
blobf9b166732e70f44f703a8a510cb4d0c850bd30a0
1 /*
2 * linux/mm/vmalloc.c
4 * Copyright (C) 1993 Linus Torvalds
5 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
6 * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
7 * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002
8 * Numa awareness, Christoph Lameter, SGI, June 2005
9 */
11 #include <linux/vmalloc.h>
12 #include <linux/mm.h>
13 #include <linux/module.h>
14 #include <linux/highmem.h>
15 #include <linux/sched.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/interrupt.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/debugobjects.h>
22 #include <linux/kallsyms.h>
23 #include <linux/list.h>
24 #include <linux/rbtree.h>
25 #include <linux/radix-tree.h>
26 #include <linux/rcupdate.h>
27 #include <linux/pfn.h>
28 #include <linux/kmemleak.h>
29 #include <asm/atomic.h>
30 #include <asm/uaccess.h>
31 #include <asm/tlbflush.h>
32 #include <asm/shmparam.h>
34 /*** Page table manipulation functions ***/
36 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end)
38 pte_t *pte;
40 pte = pte_offset_kernel(pmd, addr);
41 do {
42 pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
43 WARN_ON(!pte_none(ptent) && !pte_present(ptent));
44 } while (pte++, addr += PAGE_SIZE, addr != end);
47 static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end)
49 pmd_t *pmd;
50 unsigned long next;
52 pmd = pmd_offset(pud, addr);
53 do {
54 next = pmd_addr_end(addr, end);
55 if (pmd_none_or_clear_bad(pmd))
56 continue;
57 vunmap_pte_range(pmd, addr, next);
58 } while (pmd++, addr = next, addr != end);
61 static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end)
63 pud_t *pud;
64 unsigned long next;
66 pud = pud_offset(pgd, addr);
67 do {
68 next = pud_addr_end(addr, end);
69 if (pud_none_or_clear_bad(pud))
70 continue;
71 vunmap_pmd_range(pud, addr, next);
72 } while (pud++, addr = next, addr != end);
75 static void vunmap_page_range(unsigned long addr, unsigned long end)
77 pgd_t *pgd;
78 unsigned long next;
80 BUG_ON(addr >= end);
81 pgd = pgd_offset_k(addr);
82 do {
83 next = pgd_addr_end(addr, end);
84 if (pgd_none_or_clear_bad(pgd))
85 continue;
86 vunmap_pud_range(pgd, addr, next);
87 } while (pgd++, addr = next, addr != end);
90 static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
91 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
93 pte_t *pte;
96 * nr is a running index into the array which helps higher level
97 * callers keep track of where we're up to.
100 pte = pte_alloc_kernel(pmd, addr);
101 if (!pte)
102 return -ENOMEM;
103 do {
104 struct page *page = pages[*nr];
106 if (WARN_ON(!pte_none(*pte)))
107 return -EBUSY;
108 if (WARN_ON(!page))
109 return -ENOMEM;
110 set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
111 (*nr)++;
112 } while (pte++, addr += PAGE_SIZE, addr != end);
113 return 0;
116 static int vmap_pmd_range(pud_t *pud, unsigned long addr,
117 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
119 pmd_t *pmd;
120 unsigned long next;
122 pmd = pmd_alloc(&init_mm, pud, addr);
123 if (!pmd)
124 return -ENOMEM;
125 do {
126 next = pmd_addr_end(addr, end);
127 if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
128 return -ENOMEM;
129 } while (pmd++, addr = next, addr != end);
130 return 0;
133 static int vmap_pud_range(pgd_t *pgd, unsigned long addr,
134 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
136 pud_t *pud;
137 unsigned long next;
139 pud = pud_alloc(&init_mm, pgd, addr);
140 if (!pud)
141 return -ENOMEM;
142 do {
143 next = pud_addr_end(addr, end);
144 if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
145 return -ENOMEM;
146 } while (pud++, addr = next, addr != end);
147 return 0;
151 * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
152 * will have pfns corresponding to the "pages" array.
154 * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
156 static int vmap_page_range_noflush(unsigned long start, unsigned long end,
157 pgprot_t prot, struct page **pages)
159 pgd_t *pgd;
160 unsigned long next;
161 unsigned long addr = start;
162 int err = 0;
163 int nr = 0;
165 BUG_ON(addr >= end);
166 pgd = pgd_offset_k(addr);
167 do {
168 next = pgd_addr_end(addr, end);
169 err = vmap_pud_range(pgd, addr, next, prot, pages, &nr);
170 if (err)
171 return err;
172 } while (pgd++, addr = next, addr != end);
174 return nr;
177 static int vmap_page_range(unsigned long start, unsigned long end,
178 pgprot_t prot, struct page **pages)
180 int ret;
182 ret = vmap_page_range_noflush(start, end, prot, pages);
183 flush_cache_vmap(start, end);
184 return ret;
187 int is_vmalloc_or_module_addr(const void *x)
190 * ARM, x86-64 and sparc64 put modules in a special place,
191 * and fall back on vmalloc() if that fails. Others
192 * just put it in the vmalloc space.
194 #if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
195 unsigned long addr = (unsigned long)x;
196 if (addr >= MODULES_VADDR && addr < MODULES_END)
197 return 1;
198 #endif
199 return is_vmalloc_addr(x);
203 * Walk a vmap address to the struct page it maps.
205 struct page *vmalloc_to_page(const void *vmalloc_addr)
207 unsigned long addr = (unsigned long) vmalloc_addr;
208 struct page *page = NULL;
209 pgd_t *pgd = pgd_offset_k(addr);
212 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
213 * architectures that do not vmalloc module space
215 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
217 if (!pgd_none(*pgd)) {
218 pud_t *pud = pud_offset(pgd, addr);
219 if (!pud_none(*pud)) {
220 pmd_t *pmd = pmd_offset(pud, addr);
221 if (!pmd_none(*pmd)) {
222 pte_t *ptep, pte;
224 ptep = pte_offset_map(pmd, addr);
225 pte = *ptep;
226 if (pte_present(pte))
227 page = pte_page(pte);
228 pte_unmap(ptep);
232 return page;
234 EXPORT_SYMBOL(vmalloc_to_page);
237 * Map a vmalloc()-space virtual address to the physical page frame number.
239 unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
241 return page_to_pfn(vmalloc_to_page(vmalloc_addr));
243 EXPORT_SYMBOL(vmalloc_to_pfn);
246 /*** Global kva allocator ***/
248 #define VM_LAZY_FREE 0x01
249 #define VM_LAZY_FREEING 0x02
250 #define VM_VM_AREA 0x04
252 struct vmap_area {
253 unsigned long va_start;
254 unsigned long va_end;
255 unsigned long flags;
256 struct rb_node rb_node; /* address sorted rbtree */
257 struct list_head list; /* address sorted list */
258 struct list_head purge_list; /* "lazy purge" list */
259 void *private;
260 struct rcu_head rcu_head;
263 static DEFINE_SPINLOCK(vmap_area_lock);
264 static struct rb_root vmap_area_root = RB_ROOT;
265 static LIST_HEAD(vmap_area_list);
266 static unsigned long vmap_area_pcpu_hole;
268 static struct vmap_area *__find_vmap_area(unsigned long addr)
270 struct rb_node *n = vmap_area_root.rb_node;
272 while (n) {
273 struct vmap_area *va;
275 va = rb_entry(n, struct vmap_area, rb_node);
276 if (addr < va->va_start)
277 n = n->rb_left;
278 else if (addr > va->va_start)
279 n = n->rb_right;
280 else
281 return va;
284 return NULL;
287 static void __insert_vmap_area(struct vmap_area *va)
289 struct rb_node **p = &vmap_area_root.rb_node;
290 struct rb_node *parent = NULL;
291 struct rb_node *tmp;
293 while (*p) {
294 struct vmap_area *tmp_va;
296 parent = *p;
297 tmp_va = rb_entry(parent, struct vmap_area, rb_node);
298 if (va->va_start < tmp_va->va_end)
299 p = &(*p)->rb_left;
300 else if (va->va_end > tmp_va->va_start)
301 p = &(*p)->rb_right;
302 else
303 BUG();
306 rb_link_node(&va->rb_node, parent, p);
307 rb_insert_color(&va->rb_node, &vmap_area_root);
309 /* address-sort this list so it is usable like the vmlist */
310 tmp = rb_prev(&va->rb_node);
311 if (tmp) {
312 struct vmap_area *prev;
313 prev = rb_entry(tmp, struct vmap_area, rb_node);
314 list_add_rcu(&va->list, &prev->list);
315 } else
316 list_add_rcu(&va->list, &vmap_area_list);
319 static void purge_vmap_area_lazy(void);
322 * Allocate a region of KVA of the specified size and alignment, within the
323 * vstart and vend.
325 static struct vmap_area *alloc_vmap_area(unsigned long size,
326 unsigned long align,
327 unsigned long vstart, unsigned long vend,
328 int node, gfp_t gfp_mask)
330 struct vmap_area *va;
331 struct rb_node *n;
332 unsigned long addr;
333 int purged = 0;
335 BUG_ON(!size);
336 BUG_ON(size & ~PAGE_MASK);
338 va = kmalloc_node(sizeof(struct vmap_area),
339 gfp_mask & GFP_RECLAIM_MASK, node);
340 if (unlikely(!va))
341 return ERR_PTR(-ENOMEM);
343 retry:
344 addr = ALIGN(vstart, align);
346 spin_lock(&vmap_area_lock);
347 if (addr + size - 1 < addr)
348 goto overflow;
350 /* XXX: could have a last_hole cache */
351 n = vmap_area_root.rb_node;
352 if (n) {
353 struct vmap_area *first = NULL;
355 do {
356 struct vmap_area *tmp;
357 tmp = rb_entry(n, struct vmap_area, rb_node);
358 if (tmp->va_end >= addr) {
359 if (!first && tmp->va_start < addr + size)
360 first = tmp;
361 n = n->rb_left;
362 } else {
363 first = tmp;
364 n = n->rb_right;
366 } while (n);
368 if (!first)
369 goto found;
371 if (first->va_end < addr) {
372 n = rb_next(&first->rb_node);
373 if (n)
374 first = rb_entry(n, struct vmap_area, rb_node);
375 else
376 goto found;
379 while (addr + size > first->va_start && addr + size <= vend) {
380 addr = ALIGN(first->va_end + PAGE_SIZE, align);
381 if (addr + size - 1 < addr)
382 goto overflow;
384 n = rb_next(&first->rb_node);
385 if (n)
386 first = rb_entry(n, struct vmap_area, rb_node);
387 else
388 goto found;
391 found:
392 if (addr + size > vend) {
393 overflow:
394 spin_unlock(&vmap_area_lock);
395 if (!purged) {
396 purge_vmap_area_lazy();
397 purged = 1;
398 goto retry;
400 if (printk_ratelimit())
401 printk(KERN_WARNING
402 "vmap allocation for size %lu failed: "
403 "use vmalloc=<size> to increase size.\n", size);
404 kfree(va);
405 return ERR_PTR(-EBUSY);
408 BUG_ON(addr & (align-1));
410 va->va_start = addr;
411 va->va_end = addr + size;
412 va->flags = 0;
413 __insert_vmap_area(va);
414 spin_unlock(&vmap_area_lock);
416 return va;
419 static void rcu_free_va(struct rcu_head *head)
421 struct vmap_area *va = container_of(head, struct vmap_area, rcu_head);
423 kfree(va);
426 static void __free_vmap_area(struct vmap_area *va)
428 BUG_ON(RB_EMPTY_NODE(&va->rb_node));
429 rb_erase(&va->rb_node, &vmap_area_root);
430 RB_CLEAR_NODE(&va->rb_node);
431 list_del_rcu(&va->list);
434 * Track the highest possible candidate for pcpu area
435 * allocation. Areas outside of vmalloc area can be returned
436 * here too, consider only end addresses which fall inside
437 * vmalloc area proper.
439 if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END)
440 vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end);
442 call_rcu(&va->rcu_head, rcu_free_va);
446 * Free a region of KVA allocated by alloc_vmap_area
448 static void free_vmap_area(struct vmap_area *va)
450 spin_lock(&vmap_area_lock);
451 __free_vmap_area(va);
452 spin_unlock(&vmap_area_lock);
456 * Clear the pagetable entries of a given vmap_area
458 static void unmap_vmap_area(struct vmap_area *va)
460 vunmap_page_range(va->va_start, va->va_end);
463 static void vmap_debug_free_range(unsigned long start, unsigned long end)
466 * Unmap page tables and force a TLB flush immediately if
467 * CONFIG_DEBUG_PAGEALLOC is set. This catches use after free
468 * bugs similarly to those in linear kernel virtual address
469 * space after a page has been freed.
471 * All the lazy freeing logic is still retained, in order to
472 * minimise intrusiveness of this debugging feature.
474 * This is going to be *slow* (linear kernel virtual address
475 * debugging doesn't do a broadcast TLB flush so it is a lot
476 * faster).
478 #ifdef CONFIG_DEBUG_PAGEALLOC
479 vunmap_page_range(start, end);
480 flush_tlb_kernel_range(start, end);
481 #endif
485 * lazy_max_pages is the maximum amount of virtual address space we gather up
486 * before attempting to purge with a TLB flush.
488 * There is a tradeoff here: a larger number will cover more kernel page tables
489 * and take slightly longer to purge, but it will linearly reduce the number of
490 * global TLB flushes that must be performed. It would seem natural to scale
491 * this number up linearly with the number of CPUs (because vmapping activity
492 * could also scale linearly with the number of CPUs), however it is likely
493 * that in practice, workloads might be constrained in other ways that mean
494 * vmap activity will not scale linearly with CPUs. Also, I want to be
495 * conservative and not introduce a big latency on huge systems, so go with
496 * a less aggressive log scale. It will still be an improvement over the old
497 * code, and it will be simple to change the scale factor if we find that it
498 * becomes a problem on bigger systems.
500 static unsigned long lazy_max_pages(void)
502 unsigned int log;
504 log = fls(num_online_cpus());
506 return log * (32UL * 1024 * 1024 / PAGE_SIZE);
509 static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
511 /* for per-CPU blocks */
512 static void purge_fragmented_blocks_allcpus(void);
515 * called before a call to iounmap() if the caller wants vm_area_struct's
516 * immediately freed.
518 void set_iounmap_nonlazy(void)
520 atomic_set(&vmap_lazy_nr, lazy_max_pages()+1);
524 * Purges all lazily-freed vmap areas.
526 * If sync is 0 then don't purge if there is already a purge in progress.
527 * If force_flush is 1, then flush kernel TLBs between *start and *end even
528 * if we found no lazy vmap areas to unmap (callers can use this to optimise
529 * their own TLB flushing).
530 * Returns with *start = min(*start, lowest purged address)
531 * *end = max(*end, highest purged address)
533 static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
534 int sync, int force_flush)
536 static DEFINE_SPINLOCK(purge_lock);
537 LIST_HEAD(valist);
538 struct vmap_area *va;
539 struct vmap_area *n_va;
540 int nr = 0;
543 * If sync is 0 but force_flush is 1, we'll go sync anyway but callers
544 * should not expect such behaviour. This just simplifies locking for
545 * the case that isn't actually used at the moment anyway.
547 if (!sync && !force_flush) {
548 if (!spin_trylock(&purge_lock))
549 return;
550 } else
551 spin_lock(&purge_lock);
553 if (sync)
554 purge_fragmented_blocks_allcpus();
556 rcu_read_lock();
557 list_for_each_entry_rcu(va, &vmap_area_list, list) {
558 if (va->flags & VM_LAZY_FREE) {
559 if (va->va_start < *start)
560 *start = va->va_start;
561 if (va->va_end > *end)
562 *end = va->va_end;
563 nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
564 list_add_tail(&va->purge_list, &valist);
565 va->flags |= VM_LAZY_FREEING;
566 va->flags &= ~VM_LAZY_FREE;
569 rcu_read_unlock();
571 if (nr)
572 atomic_sub(nr, &vmap_lazy_nr);
574 if (nr || force_flush)
575 flush_tlb_kernel_range(*start, *end);
577 if (nr) {
578 spin_lock(&vmap_area_lock);
579 list_for_each_entry_safe(va, n_va, &valist, purge_list)
580 __free_vmap_area(va);
581 spin_unlock(&vmap_area_lock);
583 spin_unlock(&purge_lock);
587 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
588 * is already purging.
590 static void try_purge_vmap_area_lazy(void)
592 unsigned long start = ULONG_MAX, end = 0;
594 __purge_vmap_area_lazy(&start, &end, 0, 0);
598 * Kick off a purge of the outstanding lazy areas.
600 static void purge_vmap_area_lazy(void)
602 unsigned long start = ULONG_MAX, end = 0;
604 __purge_vmap_area_lazy(&start, &end, 1, 0);
608 * Free a vmap area, caller ensuring that the area has been unmapped
609 * and flush_cache_vunmap had been called for the correct range
610 * previously.
612 static void free_vmap_area_noflush(struct vmap_area *va)
614 va->flags |= VM_LAZY_FREE;
615 atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr);
616 if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages()))
617 try_purge_vmap_area_lazy();
621 * Free and unmap a vmap area, caller ensuring flush_cache_vunmap had been
622 * called for the correct range previously.
624 static void free_unmap_vmap_area_noflush(struct vmap_area *va)
626 unmap_vmap_area(va);
627 free_vmap_area_noflush(va);
631 * Free and unmap a vmap area
633 static void free_unmap_vmap_area(struct vmap_area *va)
635 flush_cache_vunmap(va->va_start, va->va_end);
636 free_unmap_vmap_area_noflush(va);
639 static struct vmap_area *find_vmap_area(unsigned long addr)
641 struct vmap_area *va;
643 spin_lock(&vmap_area_lock);
644 va = __find_vmap_area(addr);
645 spin_unlock(&vmap_area_lock);
647 return va;
650 static void free_unmap_vmap_area_addr(unsigned long addr)
652 struct vmap_area *va;
654 va = find_vmap_area(addr);
655 BUG_ON(!va);
656 free_unmap_vmap_area(va);
660 /*** Per cpu kva allocator ***/
663 * vmap space is limited especially on 32 bit architectures. Ensure there is
664 * room for at least 16 percpu vmap blocks per CPU.
667 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
668 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
669 * instead (we just need a rough idea)
671 #if BITS_PER_LONG == 32
672 #define VMALLOC_SPACE (128UL*1024*1024)
673 #else
674 #define VMALLOC_SPACE (128UL*1024*1024*1024)
675 #endif
677 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
678 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
679 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
680 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
681 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
682 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
683 #define VMAP_BBMAP_BITS VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
684 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
685 VMALLOC_PAGES / NR_CPUS / 16))
687 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
689 static bool vmap_initialized __read_mostly = false;
691 struct vmap_block_queue {
692 spinlock_t lock;
693 struct list_head free;
696 struct vmap_block {
697 spinlock_t lock;
698 struct vmap_area *va;
699 struct vmap_block_queue *vbq;
700 unsigned long free, dirty;
701 DECLARE_BITMAP(alloc_map, VMAP_BBMAP_BITS);
702 DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS);
703 struct list_head free_list;
704 struct rcu_head rcu_head;
705 struct list_head purge;
708 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
709 static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
712 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
713 * in the free path. Could get rid of this if we change the API to return a
714 * "cookie" from alloc, to be passed to free. But no big deal yet.
716 static DEFINE_SPINLOCK(vmap_block_tree_lock);
717 static RADIX_TREE(vmap_block_tree, GFP_ATOMIC);
720 * We should probably have a fallback mechanism to allocate virtual memory
721 * out of partially filled vmap blocks. However vmap block sizing should be
722 * fairly reasonable according to the vmalloc size, so it shouldn't be a
723 * big problem.
726 static unsigned long addr_to_vb_idx(unsigned long addr)
728 addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
729 addr /= VMAP_BLOCK_SIZE;
730 return addr;
733 static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
735 struct vmap_block_queue *vbq;
736 struct vmap_block *vb;
737 struct vmap_area *va;
738 unsigned long vb_idx;
739 int node, err;
741 node = numa_node_id();
743 vb = kmalloc_node(sizeof(struct vmap_block),
744 gfp_mask & GFP_RECLAIM_MASK, node);
745 if (unlikely(!vb))
746 return ERR_PTR(-ENOMEM);
748 va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
749 VMALLOC_START, VMALLOC_END,
750 node, gfp_mask);
751 if (IS_ERR(va)) {
752 kfree(vb);
753 return ERR_CAST(va);
756 err = radix_tree_preload(gfp_mask);
757 if (unlikely(err)) {
758 kfree(vb);
759 free_vmap_area(va);
760 return ERR_PTR(err);
763 spin_lock_init(&vb->lock);
764 vb->va = va;
765 vb->free = VMAP_BBMAP_BITS;
766 vb->dirty = 0;
767 bitmap_zero(vb->alloc_map, VMAP_BBMAP_BITS);
768 bitmap_zero(vb->dirty_map, VMAP_BBMAP_BITS);
769 INIT_LIST_HEAD(&vb->free_list);
771 vb_idx = addr_to_vb_idx(va->va_start);
772 spin_lock(&vmap_block_tree_lock);
773 err = radix_tree_insert(&vmap_block_tree, vb_idx, vb);
774 spin_unlock(&vmap_block_tree_lock);
775 BUG_ON(err);
776 radix_tree_preload_end();
778 vbq = &get_cpu_var(vmap_block_queue);
779 vb->vbq = vbq;
780 spin_lock(&vbq->lock);
781 list_add_rcu(&vb->free_list, &vbq->free);
782 spin_unlock(&vbq->lock);
783 put_cpu_var(vmap_block_queue);
785 return vb;
788 static void rcu_free_vb(struct rcu_head *head)
790 struct vmap_block *vb = container_of(head, struct vmap_block, rcu_head);
792 kfree(vb);
795 static void free_vmap_block(struct vmap_block *vb)
797 struct vmap_block *tmp;
798 unsigned long vb_idx;
800 vb_idx = addr_to_vb_idx(vb->va->va_start);
801 spin_lock(&vmap_block_tree_lock);
802 tmp = radix_tree_delete(&vmap_block_tree, vb_idx);
803 spin_unlock(&vmap_block_tree_lock);
804 BUG_ON(tmp != vb);
806 free_vmap_area_noflush(vb->va);
807 call_rcu(&vb->rcu_head, rcu_free_vb);
810 static void purge_fragmented_blocks(int cpu)
812 LIST_HEAD(purge);
813 struct vmap_block *vb;
814 struct vmap_block *n_vb;
815 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
817 rcu_read_lock();
818 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
820 if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
821 continue;
823 spin_lock(&vb->lock);
824 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
825 vb->free = 0; /* prevent further allocs after releasing lock */
826 vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
827 bitmap_fill(vb->alloc_map, VMAP_BBMAP_BITS);
828 bitmap_fill(vb->dirty_map, VMAP_BBMAP_BITS);
829 spin_lock(&vbq->lock);
830 list_del_rcu(&vb->free_list);
831 spin_unlock(&vbq->lock);
832 spin_unlock(&vb->lock);
833 list_add_tail(&vb->purge, &purge);
834 } else
835 spin_unlock(&vb->lock);
837 rcu_read_unlock();
839 list_for_each_entry_safe(vb, n_vb, &purge, purge) {
840 list_del(&vb->purge);
841 free_vmap_block(vb);
845 static void purge_fragmented_blocks_thiscpu(void)
847 purge_fragmented_blocks(smp_processor_id());
850 static void purge_fragmented_blocks_allcpus(void)
852 int cpu;
854 for_each_possible_cpu(cpu)
855 purge_fragmented_blocks(cpu);
858 static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
860 struct vmap_block_queue *vbq;
861 struct vmap_block *vb;
862 unsigned long addr = 0;
863 unsigned int order;
864 int purge = 0;
866 BUG_ON(size & ~PAGE_MASK);
867 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
868 order = get_order(size);
870 again:
871 rcu_read_lock();
872 vbq = &get_cpu_var(vmap_block_queue);
873 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
874 int i;
876 spin_lock(&vb->lock);
877 if (vb->free < 1UL << order)
878 goto next;
880 i = bitmap_find_free_region(vb->alloc_map,
881 VMAP_BBMAP_BITS, order);
883 if (i < 0) {
884 if (vb->free + vb->dirty == VMAP_BBMAP_BITS) {
885 /* fragmented and no outstanding allocations */
886 BUG_ON(vb->dirty != VMAP_BBMAP_BITS);
887 purge = 1;
889 goto next;
891 addr = vb->va->va_start + (i << PAGE_SHIFT);
892 BUG_ON(addr_to_vb_idx(addr) !=
893 addr_to_vb_idx(vb->va->va_start));
894 vb->free -= 1UL << order;
895 if (vb->free == 0) {
896 spin_lock(&vbq->lock);
897 list_del_rcu(&vb->free_list);
898 spin_unlock(&vbq->lock);
900 spin_unlock(&vb->lock);
901 break;
902 next:
903 spin_unlock(&vb->lock);
906 if (purge)
907 purge_fragmented_blocks_thiscpu();
909 put_cpu_var(vmap_block_queue);
910 rcu_read_unlock();
912 if (!addr) {
913 vb = new_vmap_block(gfp_mask);
914 if (IS_ERR(vb))
915 return vb;
916 goto again;
919 return (void *)addr;
922 static void vb_free(const void *addr, unsigned long size)
924 unsigned long offset;
925 unsigned long vb_idx;
926 unsigned int order;
927 struct vmap_block *vb;
929 BUG_ON(size & ~PAGE_MASK);
930 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
932 flush_cache_vunmap((unsigned long)addr, (unsigned long)addr + size);
934 order = get_order(size);
936 offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1);
938 vb_idx = addr_to_vb_idx((unsigned long)addr);
939 rcu_read_lock();
940 vb = radix_tree_lookup(&vmap_block_tree, vb_idx);
941 rcu_read_unlock();
942 BUG_ON(!vb);
944 vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
946 spin_lock(&vb->lock);
947 BUG_ON(bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order));
949 vb->dirty += 1UL << order;
950 if (vb->dirty == VMAP_BBMAP_BITS) {
951 BUG_ON(vb->free);
952 spin_unlock(&vb->lock);
953 free_vmap_block(vb);
954 } else
955 spin_unlock(&vb->lock);
959 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
961 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
962 * to amortize TLB flushing overheads. What this means is that any page you
963 * have now, may, in a former life, have been mapped into kernel virtual
964 * address by the vmap layer and so there might be some CPUs with TLB entries
965 * still referencing that page (additional to the regular 1:1 kernel mapping).
967 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
968 * be sure that none of the pages we have control over will have any aliases
969 * from the vmap layer.
971 void vm_unmap_aliases(void)
973 unsigned long start = ULONG_MAX, end = 0;
974 int cpu;
975 int flush = 0;
977 if (unlikely(!vmap_initialized))
978 return;
980 for_each_possible_cpu(cpu) {
981 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
982 struct vmap_block *vb;
984 rcu_read_lock();
985 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
986 int i;
988 spin_lock(&vb->lock);
989 i = find_first_bit(vb->dirty_map, VMAP_BBMAP_BITS);
990 while (i < VMAP_BBMAP_BITS) {
991 unsigned long s, e;
992 int j;
993 j = find_next_zero_bit(vb->dirty_map,
994 VMAP_BBMAP_BITS, i);
996 s = vb->va->va_start + (i << PAGE_SHIFT);
997 e = vb->va->va_start + (j << PAGE_SHIFT);
998 flush = 1;
1000 if (s < start)
1001 start = s;
1002 if (e > end)
1003 end = e;
1005 i = j;
1006 i = find_next_bit(vb->dirty_map,
1007 VMAP_BBMAP_BITS, i);
1009 spin_unlock(&vb->lock);
1011 rcu_read_unlock();
1014 __purge_vmap_area_lazy(&start, &end, 1, flush);
1016 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
1019 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1020 * @mem: the pointer returned by vm_map_ram
1021 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1023 void vm_unmap_ram(const void *mem, unsigned int count)
1025 unsigned long size = count << PAGE_SHIFT;
1026 unsigned long addr = (unsigned long)mem;
1028 BUG_ON(!addr);
1029 BUG_ON(addr < VMALLOC_START);
1030 BUG_ON(addr > VMALLOC_END);
1031 BUG_ON(addr & (PAGE_SIZE-1));
1033 debug_check_no_locks_freed(mem, size);
1034 vmap_debug_free_range(addr, addr+size);
1036 if (likely(count <= VMAP_MAX_ALLOC))
1037 vb_free(mem, size);
1038 else
1039 free_unmap_vmap_area_addr(addr);
1041 EXPORT_SYMBOL(vm_unmap_ram);
1044 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1045 * @pages: an array of pointers to the pages to be mapped
1046 * @count: number of pages
1047 * @node: prefer to allocate data structures on this node
1048 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
1050 * Returns: a pointer to the address that has been mapped, or %NULL on failure
1052 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
1054 unsigned long size = count << PAGE_SHIFT;
1055 unsigned long addr;
1056 void *mem;
1058 if (likely(count <= VMAP_MAX_ALLOC)) {
1059 mem = vb_alloc(size, GFP_KERNEL);
1060 if (IS_ERR(mem))
1061 return NULL;
1062 addr = (unsigned long)mem;
1063 } else {
1064 struct vmap_area *va;
1065 va = alloc_vmap_area(size, PAGE_SIZE,
1066 VMALLOC_START, VMALLOC_END, node, GFP_KERNEL);
1067 if (IS_ERR(va))
1068 return NULL;
1070 addr = va->va_start;
1071 mem = (void *)addr;
1073 if (vmap_page_range(addr, addr + size, prot, pages) < 0) {
1074 vm_unmap_ram(mem, count);
1075 return NULL;
1077 return mem;
1079 EXPORT_SYMBOL(vm_map_ram);
1082 * vm_area_register_early - register vmap area early during boot
1083 * @vm: vm_struct to register
1084 * @align: requested alignment
1086 * This function is used to register kernel vm area before
1087 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1088 * proper values on entry and other fields should be zero. On return,
1089 * vm->addr contains the allocated address.
1091 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1093 void __init vm_area_register_early(struct vm_struct *vm, size_t align)
1095 static size_t vm_init_off __initdata;
1096 unsigned long addr;
1098 addr = ALIGN(VMALLOC_START + vm_init_off, align);
1099 vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START;
1101 vm->addr = (void *)addr;
1103 vm->next = vmlist;
1104 vmlist = vm;
1107 void __init vmalloc_init(void)
1109 struct vmap_area *va;
1110 struct vm_struct *tmp;
1111 int i;
1113 for_each_possible_cpu(i) {
1114 struct vmap_block_queue *vbq;
1116 vbq = &per_cpu(vmap_block_queue, i);
1117 spin_lock_init(&vbq->lock);
1118 INIT_LIST_HEAD(&vbq->free);
1121 /* Import existing vmlist entries. */
1122 for (tmp = vmlist; tmp; tmp = tmp->next) {
1123 va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT);
1124 va->flags = tmp->flags | VM_VM_AREA;
1125 va->va_start = (unsigned long)tmp->addr;
1126 va->va_end = va->va_start + tmp->size;
1127 __insert_vmap_area(va);
1130 vmap_area_pcpu_hole = VMALLOC_END;
1132 vmap_initialized = true;
1136 * map_kernel_range_noflush - map kernel VM area with the specified pages
1137 * @addr: start of the VM area to map
1138 * @size: size of the VM area to map
1139 * @prot: page protection flags to use
1140 * @pages: pages to map
1142 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1143 * specify should have been allocated using get_vm_area() and its
1144 * friends.
1146 * NOTE:
1147 * This function does NOT do any cache flushing. The caller is
1148 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1149 * before calling this function.
1151 * RETURNS:
1152 * The number of pages mapped on success, -errno on failure.
1154 int map_kernel_range_noflush(unsigned long addr, unsigned long size,
1155 pgprot_t prot, struct page **pages)
1157 return vmap_page_range_noflush(addr, addr + size, prot, pages);
1161 * unmap_kernel_range_noflush - unmap kernel VM area
1162 * @addr: start of the VM area to unmap
1163 * @size: size of the VM area to unmap
1165 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1166 * specify should have been allocated using get_vm_area() and its
1167 * friends.
1169 * NOTE:
1170 * This function does NOT do any cache flushing. The caller is
1171 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1172 * before calling this function and flush_tlb_kernel_range() after.
1174 void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
1176 vunmap_page_range(addr, addr + size);
1178 EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush);
1181 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1182 * @addr: start of the VM area to unmap
1183 * @size: size of the VM area to unmap
1185 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1186 * the unmapping and tlb after.
1188 void unmap_kernel_range(unsigned long addr, unsigned long size)
1190 unsigned long end = addr + size;
1192 flush_cache_vunmap(addr, end);
1193 vunmap_page_range(addr, end);
1194 flush_tlb_kernel_range(addr, end);
1197 int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page ***pages)
1199 unsigned long addr = (unsigned long)area->addr;
1200 unsigned long end = addr + area->size - PAGE_SIZE;
1201 int err;
1203 err = vmap_page_range(addr, end, prot, *pages);
1204 if (err > 0) {
1205 *pages += err;
1206 err = 0;
1209 return err;
1211 EXPORT_SYMBOL_GPL(map_vm_area);
1213 /*** Old vmalloc interfaces ***/
1214 DEFINE_RWLOCK(vmlist_lock);
1215 struct vm_struct *vmlist;
1217 static void insert_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
1218 unsigned long flags, void *caller)
1220 struct vm_struct *tmp, **p;
1222 vm->flags = flags;
1223 vm->addr = (void *)va->va_start;
1224 vm->size = va->va_end - va->va_start;
1225 vm->caller = caller;
1226 va->private = vm;
1227 va->flags |= VM_VM_AREA;
1229 write_lock(&vmlist_lock);
1230 for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
1231 if (tmp->addr >= vm->addr)
1232 break;
1234 vm->next = *p;
1235 *p = vm;
1236 write_unlock(&vmlist_lock);
1239 static struct vm_struct *__get_vm_area_node(unsigned long size,
1240 unsigned long align, unsigned long flags, unsigned long start,
1241 unsigned long end, int node, gfp_t gfp_mask, void *caller)
1243 static struct vmap_area *va;
1244 struct vm_struct *area;
1246 BUG_ON(in_interrupt());
1247 if (flags & VM_IOREMAP) {
1248 int bit = fls(size);
1250 if (bit > IOREMAP_MAX_ORDER)
1251 bit = IOREMAP_MAX_ORDER;
1252 else if (bit < PAGE_SHIFT)
1253 bit = PAGE_SHIFT;
1255 align = 1ul << bit;
1258 size = PAGE_ALIGN(size);
1259 if (unlikely(!size))
1260 return NULL;
1262 area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
1263 if (unlikely(!area))
1264 return NULL;
1267 * We always allocate a guard page.
1269 size += PAGE_SIZE;
1271 va = alloc_vmap_area(size, align, start, end, node, gfp_mask);
1272 if (IS_ERR(va)) {
1273 kfree(area);
1274 return NULL;
1277 insert_vmalloc_vm(area, va, flags, caller);
1278 return area;
1281 struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
1282 unsigned long start, unsigned long end)
1284 return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL,
1285 __builtin_return_address(0));
1287 EXPORT_SYMBOL_GPL(__get_vm_area);
1289 struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
1290 unsigned long start, unsigned long end,
1291 void *caller)
1293 return __get_vm_area_node(size, 1, flags, start, end, -1, GFP_KERNEL,
1294 caller);
1298 * get_vm_area - reserve a contiguous kernel virtual area
1299 * @size: size of the area
1300 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
1302 * Search an area of @size in the kernel virtual mapping area,
1303 * and reserved it for out purposes. Returns the area descriptor
1304 * on success or %NULL on failure.
1306 struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
1308 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1309 -1, GFP_KERNEL, __builtin_return_address(0));
1312 struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
1313 void *caller)
1315 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1316 -1, GFP_KERNEL, caller);
1319 static struct vm_struct *find_vm_area(const void *addr)
1321 struct vmap_area *va;
1323 va = find_vmap_area((unsigned long)addr);
1324 if (va && va->flags & VM_VM_AREA)
1325 return va->private;
1327 return NULL;
1331 * remove_vm_area - find and remove a continuous kernel virtual area
1332 * @addr: base address
1334 * Search for the kernel VM area starting at @addr, and remove it.
1335 * This function returns the found VM area, but using it is NOT safe
1336 * on SMP machines, except for its size or flags.
1338 struct vm_struct *remove_vm_area(const void *addr)
1340 struct vmap_area *va;
1342 va = find_vmap_area((unsigned long)addr);
1343 if (va && va->flags & VM_VM_AREA) {
1344 struct vm_struct *vm = va->private;
1345 struct vm_struct *tmp, **p;
1347 * remove from list and disallow access to this vm_struct
1348 * before unmap. (address range confliction is maintained by
1349 * vmap.)
1351 write_lock(&vmlist_lock);
1352 for (p = &vmlist; (tmp = *p) != vm; p = &tmp->next)
1354 *p = tmp->next;
1355 write_unlock(&vmlist_lock);
1357 vmap_debug_free_range(va->va_start, va->va_end);
1358 free_unmap_vmap_area(va);
1359 vm->size -= PAGE_SIZE;
1361 return vm;
1363 return NULL;
1366 static void __vunmap(const void *addr, int deallocate_pages)
1368 struct vm_struct *area;
1370 if (!addr)
1371 return;
1373 if ((PAGE_SIZE-1) & (unsigned long)addr) {
1374 WARN(1, KERN_ERR "Trying to vfree() bad address (%p)\n", addr);
1375 return;
1378 area = remove_vm_area(addr);
1379 if (unlikely(!area)) {
1380 WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
1381 addr);
1382 return;
1385 debug_check_no_locks_freed(addr, area->size);
1386 debug_check_no_obj_freed(addr, area->size);
1388 if (deallocate_pages) {
1389 int i;
1391 for (i = 0; i < area->nr_pages; i++) {
1392 struct page *page = area->pages[i];
1394 BUG_ON(!page);
1395 __free_page(page);
1398 if (area->flags & VM_VPAGES)
1399 vfree(area->pages);
1400 else
1401 kfree(area->pages);
1404 kfree(area);
1405 return;
1409 * vfree - release memory allocated by vmalloc()
1410 * @addr: memory base address
1412 * Free the virtually continuous memory area starting at @addr, as
1413 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
1414 * NULL, no operation is performed.
1416 * Must not be called in interrupt context.
1418 void vfree(const void *addr)
1420 BUG_ON(in_interrupt());
1422 kmemleak_free(addr);
1424 __vunmap(addr, 1);
1426 EXPORT_SYMBOL(vfree);
1429 * vunmap - release virtual mapping obtained by vmap()
1430 * @addr: memory base address
1432 * Free the virtually contiguous memory area starting at @addr,
1433 * which was created from the page array passed to vmap().
1435 * Must not be called in interrupt context.
1437 void vunmap(const void *addr)
1439 BUG_ON(in_interrupt());
1440 might_sleep();
1441 __vunmap(addr, 0);
1443 EXPORT_SYMBOL(vunmap);
1446 * vmap - map an array of pages into virtually contiguous space
1447 * @pages: array of page pointers
1448 * @count: number of pages to map
1449 * @flags: vm_area->flags
1450 * @prot: page protection for the mapping
1452 * Maps @count pages from @pages into contiguous kernel virtual
1453 * space.
1455 void *vmap(struct page **pages, unsigned int count,
1456 unsigned long flags, pgprot_t prot)
1458 struct vm_struct *area;
1460 might_sleep();
1462 if (count > totalram_pages)
1463 return NULL;
1465 area = get_vm_area_caller((count << PAGE_SHIFT), flags,
1466 __builtin_return_address(0));
1467 if (!area)
1468 return NULL;
1470 if (map_vm_area(area, prot, &pages)) {
1471 vunmap(area->addr);
1472 return NULL;
1475 return area->addr;
1477 EXPORT_SYMBOL(vmap);
1479 static void *__vmalloc_node(unsigned long size, unsigned long align,
1480 gfp_t gfp_mask, pgprot_t prot,
1481 int node, void *caller);
1482 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
1483 pgprot_t prot, int node, void *caller)
1485 struct page **pages;
1486 unsigned int nr_pages, array_size, i;
1487 gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
1489 nr_pages = (area->size - PAGE_SIZE) >> PAGE_SHIFT;
1490 array_size = (nr_pages * sizeof(struct page *));
1492 area->nr_pages = nr_pages;
1493 /* Please note that the recursion is strictly bounded. */
1494 if (array_size > PAGE_SIZE) {
1495 pages = __vmalloc_node(array_size, 1, nested_gfp|__GFP_HIGHMEM,
1496 PAGE_KERNEL, node, caller);
1497 area->flags |= VM_VPAGES;
1498 } else {
1499 pages = kmalloc_node(array_size, nested_gfp, node);
1501 area->pages = pages;
1502 area->caller = caller;
1503 if (!area->pages) {
1504 remove_vm_area(area->addr);
1505 kfree(area);
1506 return NULL;
1509 for (i = 0; i < area->nr_pages; i++) {
1510 struct page *page;
1512 if (node < 0)
1513 page = alloc_page(gfp_mask);
1514 else
1515 page = alloc_pages_node(node, gfp_mask, 0);
1517 if (unlikely(!page)) {
1518 /* Successfully allocated i pages, free them in __vunmap() */
1519 area->nr_pages = i;
1520 goto fail;
1522 area->pages[i] = page;
1525 if (map_vm_area(area, prot, &pages))
1526 goto fail;
1527 return area->addr;
1529 fail:
1530 vfree(area->addr);
1531 return NULL;
1535 * __vmalloc_node_range - allocate virtually contiguous memory
1536 * @size: allocation size
1537 * @align: desired alignment
1538 * @start: vm area range start
1539 * @end: vm area range end
1540 * @gfp_mask: flags for the page level allocator
1541 * @prot: protection mask for the allocated pages
1542 * @node: node to use for allocation or -1
1543 * @caller: caller's return address
1545 * Allocate enough pages to cover @size from the page level
1546 * allocator with @gfp_mask flags. Map them into contiguous
1547 * kernel virtual space, using a pagetable protection of @prot.
1549 void *__vmalloc_node_range(unsigned long size, unsigned long align,
1550 unsigned long start, unsigned long end, gfp_t gfp_mask,
1551 pgprot_t prot, int node, void *caller)
1553 struct vm_struct *area;
1554 void *addr;
1555 unsigned long real_size = size;
1557 size = PAGE_ALIGN(size);
1558 if (!size || (size >> PAGE_SHIFT) > totalram_pages)
1559 return NULL;
1561 area = __get_vm_area_node(size, align, VM_ALLOC, start, end, node,
1562 gfp_mask, caller);
1564 if (!area)
1565 return NULL;
1567 addr = __vmalloc_area_node(area, gfp_mask, prot, node, caller);
1570 * A ref_count = 3 is needed because the vm_struct and vmap_area
1571 * structures allocated in the __get_vm_area_node() function contain
1572 * references to the virtual address of the vmalloc'ed block.
1574 kmemleak_alloc(addr, real_size, 3, gfp_mask);
1576 return addr;
1580 * __vmalloc_node - allocate virtually contiguous memory
1581 * @size: allocation size
1582 * @align: desired alignment
1583 * @gfp_mask: flags for the page level allocator
1584 * @prot: protection mask for the allocated pages
1585 * @node: node to use for allocation or -1
1586 * @caller: caller's return address
1588 * Allocate enough pages to cover @size from the page level
1589 * allocator with @gfp_mask flags. Map them into contiguous
1590 * kernel virtual space, using a pagetable protection of @prot.
1592 static void *__vmalloc_node(unsigned long size, unsigned long align,
1593 gfp_t gfp_mask, pgprot_t prot,
1594 int node, void *caller)
1596 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
1597 gfp_mask, prot, node, caller);
1600 void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
1602 return __vmalloc_node(size, 1, gfp_mask, prot, -1,
1603 __builtin_return_address(0));
1605 EXPORT_SYMBOL(__vmalloc);
1607 static inline void *__vmalloc_node_flags(unsigned long size,
1608 int node, gfp_t flags)
1610 return __vmalloc_node(size, 1, flags, PAGE_KERNEL,
1611 node, __builtin_return_address(0));
1615 * vmalloc - allocate virtually contiguous memory
1616 * @size: allocation size
1617 * Allocate enough pages to cover @size from the page level
1618 * allocator and map them into contiguous kernel virtual space.
1620 * For tight control over page level allocator and protection flags
1621 * use __vmalloc() instead.
1623 void *vmalloc(unsigned long size)
1625 return __vmalloc_node_flags(size, -1, GFP_KERNEL | __GFP_HIGHMEM);
1627 EXPORT_SYMBOL(vmalloc);
1630 * vzalloc - allocate virtually contiguous memory with zero fill
1631 * @size: allocation size
1632 * Allocate enough pages to cover @size from the page level
1633 * allocator and map them into contiguous kernel virtual space.
1634 * The memory allocated is set to zero.
1636 * For tight control over page level allocator and protection flags
1637 * use __vmalloc() instead.
1639 void *vzalloc(unsigned long size)
1641 return __vmalloc_node_flags(size, -1,
1642 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
1644 EXPORT_SYMBOL(vzalloc);
1647 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
1648 * @size: allocation size
1650 * The resulting memory area is zeroed so it can be mapped to userspace
1651 * without leaking data.
1653 void *vmalloc_user(unsigned long size)
1655 struct vm_struct *area;
1656 void *ret;
1658 ret = __vmalloc_node(size, SHMLBA,
1659 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
1660 PAGE_KERNEL, -1, __builtin_return_address(0));
1661 if (ret) {
1662 area = find_vm_area(ret);
1663 area->flags |= VM_USERMAP;
1665 return ret;
1667 EXPORT_SYMBOL(vmalloc_user);
1670 * vmalloc_node - allocate memory on a specific node
1671 * @size: allocation size
1672 * @node: numa node
1674 * Allocate enough pages to cover @size from the page level
1675 * allocator and map them into contiguous kernel virtual space.
1677 * For tight control over page level allocator and protection flags
1678 * use __vmalloc() instead.
1680 void *vmalloc_node(unsigned long size, int node)
1682 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL,
1683 node, __builtin_return_address(0));
1685 EXPORT_SYMBOL(vmalloc_node);
1688 * vzalloc_node - allocate memory on a specific node with zero fill
1689 * @size: allocation size
1690 * @node: numa node
1692 * Allocate enough pages to cover @size from the page level
1693 * allocator and map them into contiguous kernel virtual space.
1694 * The memory allocated is set to zero.
1696 * For tight control over page level allocator and protection flags
1697 * use __vmalloc_node() instead.
1699 void *vzalloc_node(unsigned long size, int node)
1701 return __vmalloc_node_flags(size, node,
1702 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
1704 EXPORT_SYMBOL(vzalloc_node);
1706 #ifndef PAGE_KERNEL_EXEC
1707 # define PAGE_KERNEL_EXEC PAGE_KERNEL
1708 #endif
1711 * vmalloc_exec - allocate virtually contiguous, executable memory
1712 * @size: allocation size
1714 * Kernel-internal function to allocate enough pages to cover @size
1715 * the page level allocator and map them into contiguous and
1716 * executable kernel virtual space.
1718 * For tight control over page level allocator and protection flags
1719 * use __vmalloc() instead.
1722 void *vmalloc_exec(unsigned long size)
1724 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
1725 -1, __builtin_return_address(0));
1728 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
1729 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
1730 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
1731 #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
1732 #else
1733 #define GFP_VMALLOC32 GFP_KERNEL
1734 #endif
1737 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
1738 * @size: allocation size
1740 * Allocate enough 32bit PA addressable pages to cover @size from the
1741 * page level allocator and map them into contiguous kernel virtual space.
1743 void *vmalloc_32(unsigned long size)
1745 return __vmalloc_node(size, 1, GFP_VMALLOC32, PAGE_KERNEL,
1746 -1, __builtin_return_address(0));
1748 EXPORT_SYMBOL(vmalloc_32);
1751 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
1752 * @size: allocation size
1754 * The resulting memory area is 32bit addressable and zeroed so it can be
1755 * mapped to userspace without leaking data.
1757 void *vmalloc_32_user(unsigned long size)
1759 struct vm_struct *area;
1760 void *ret;
1762 ret = __vmalloc_node(size, 1, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
1763 -1, __builtin_return_address(0));
1764 if (ret) {
1765 area = find_vm_area(ret);
1766 area->flags |= VM_USERMAP;
1768 return ret;
1770 EXPORT_SYMBOL(vmalloc_32_user);
1773 * small helper routine , copy contents to buf from addr.
1774 * If the page is not present, fill zero.
1777 static int aligned_vread(char *buf, char *addr, unsigned long count)
1779 struct page *p;
1780 int copied = 0;
1782 while (count) {
1783 unsigned long offset, length;
1785 offset = (unsigned long)addr & ~PAGE_MASK;
1786 length = PAGE_SIZE - offset;
1787 if (length > count)
1788 length = count;
1789 p = vmalloc_to_page(addr);
1791 * To do safe access to this _mapped_ area, we need
1792 * lock. But adding lock here means that we need to add
1793 * overhead of vmalloc()/vfree() calles for this _debug_
1794 * interface, rarely used. Instead of that, we'll use
1795 * kmap() and get small overhead in this access function.
1797 if (p) {
1799 * we can expect USER0 is not used (see vread/vwrite's
1800 * function description)
1802 void *map = kmap_atomic(p, KM_USER0);
1803 memcpy(buf, map + offset, length);
1804 kunmap_atomic(map, KM_USER0);
1805 } else
1806 memset(buf, 0, length);
1808 addr += length;
1809 buf += length;
1810 copied += length;
1811 count -= length;
1813 return copied;
1816 static int aligned_vwrite(char *buf, char *addr, unsigned long count)
1818 struct page *p;
1819 int copied = 0;
1821 while (count) {
1822 unsigned long offset, length;
1824 offset = (unsigned long)addr & ~PAGE_MASK;
1825 length = PAGE_SIZE - offset;
1826 if (length > count)
1827 length = count;
1828 p = vmalloc_to_page(addr);
1830 * To do safe access to this _mapped_ area, we need
1831 * lock. But adding lock here means that we need to add
1832 * overhead of vmalloc()/vfree() calles for this _debug_
1833 * interface, rarely used. Instead of that, we'll use
1834 * kmap() and get small overhead in this access function.
1836 if (p) {
1838 * we can expect USER0 is not used (see vread/vwrite's
1839 * function description)
1841 void *map = kmap_atomic(p, KM_USER0);
1842 memcpy(map + offset, buf, length);
1843 kunmap_atomic(map, KM_USER0);
1845 addr += length;
1846 buf += length;
1847 copied += length;
1848 count -= length;
1850 return copied;
1854 * vread() - read vmalloc area in a safe way.
1855 * @buf: buffer for reading data
1856 * @addr: vm address.
1857 * @count: number of bytes to be read.
1859 * Returns # of bytes which addr and buf should be increased.
1860 * (same number to @count). Returns 0 if [addr...addr+count) doesn't
1861 * includes any intersect with alive vmalloc area.
1863 * This function checks that addr is a valid vmalloc'ed area, and
1864 * copy data from that area to a given buffer. If the given memory range
1865 * of [addr...addr+count) includes some valid address, data is copied to
1866 * proper area of @buf. If there are memory holes, they'll be zero-filled.
1867 * IOREMAP area is treated as memory hole and no copy is done.
1869 * If [addr...addr+count) doesn't includes any intersects with alive
1870 * vm_struct area, returns 0.
1871 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1872 * the caller should guarantee KM_USER0 is not used.
1874 * Note: In usual ops, vread() is never necessary because the caller
1875 * should know vmalloc() area is valid and can use memcpy().
1876 * This is for routines which have to access vmalloc area without
1877 * any informaion, as /dev/kmem.
1881 long vread(char *buf, char *addr, unsigned long count)
1883 struct vm_struct *tmp;
1884 char *vaddr, *buf_start = buf;
1885 unsigned long buflen = count;
1886 unsigned long n;
1888 /* Don't allow overflow */
1889 if ((unsigned long) addr + count < count)
1890 count = -(unsigned long) addr;
1892 read_lock(&vmlist_lock);
1893 for (tmp = vmlist; count && tmp; tmp = tmp->next) {
1894 vaddr = (char *) tmp->addr;
1895 if (addr >= vaddr + tmp->size - PAGE_SIZE)
1896 continue;
1897 while (addr < vaddr) {
1898 if (count == 0)
1899 goto finished;
1900 *buf = '\0';
1901 buf++;
1902 addr++;
1903 count--;
1905 n = vaddr + tmp->size - PAGE_SIZE - addr;
1906 if (n > count)
1907 n = count;
1908 if (!(tmp->flags & VM_IOREMAP))
1909 aligned_vread(buf, addr, n);
1910 else /* IOREMAP area is treated as memory hole */
1911 memset(buf, 0, n);
1912 buf += n;
1913 addr += n;
1914 count -= n;
1916 finished:
1917 read_unlock(&vmlist_lock);
1919 if (buf == buf_start)
1920 return 0;
1921 /* zero-fill memory holes */
1922 if (buf != buf_start + buflen)
1923 memset(buf, 0, buflen - (buf - buf_start));
1925 return buflen;
1929 * vwrite() - write vmalloc area in a safe way.
1930 * @buf: buffer for source data
1931 * @addr: vm address.
1932 * @count: number of bytes to be read.
1934 * Returns # of bytes which addr and buf should be incresed.
1935 * (same number to @count).
1936 * If [addr...addr+count) doesn't includes any intersect with valid
1937 * vmalloc area, returns 0.
1939 * This function checks that addr is a valid vmalloc'ed area, and
1940 * copy data from a buffer to the given addr. If specified range of
1941 * [addr...addr+count) includes some valid address, data is copied from
1942 * proper area of @buf. If there are memory holes, no copy to hole.
1943 * IOREMAP area is treated as memory hole and no copy is done.
1945 * If [addr...addr+count) doesn't includes any intersects with alive
1946 * vm_struct area, returns 0.
1947 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1948 * the caller should guarantee KM_USER0 is not used.
1950 * Note: In usual ops, vwrite() is never necessary because the caller
1951 * should know vmalloc() area is valid and can use memcpy().
1952 * This is for routines which have to access vmalloc area without
1953 * any informaion, as /dev/kmem.
1955 * The caller should guarantee KM_USER1 is not used.
1958 long vwrite(char *buf, char *addr, unsigned long count)
1960 struct vm_struct *tmp;
1961 char *vaddr;
1962 unsigned long n, buflen;
1963 int copied = 0;
1965 /* Don't allow overflow */
1966 if ((unsigned long) addr + count < count)
1967 count = -(unsigned long) addr;
1968 buflen = count;
1970 read_lock(&vmlist_lock);
1971 for (tmp = vmlist; count && tmp; tmp = tmp->next) {
1972 vaddr = (char *) tmp->addr;
1973 if (addr >= vaddr + tmp->size - PAGE_SIZE)
1974 continue;
1975 while (addr < vaddr) {
1976 if (count == 0)
1977 goto finished;
1978 buf++;
1979 addr++;
1980 count--;
1982 n = vaddr + tmp->size - PAGE_SIZE - addr;
1983 if (n > count)
1984 n = count;
1985 if (!(tmp->flags & VM_IOREMAP)) {
1986 aligned_vwrite(buf, addr, n);
1987 copied++;
1989 buf += n;
1990 addr += n;
1991 count -= n;
1993 finished:
1994 read_unlock(&vmlist_lock);
1995 if (!copied)
1996 return 0;
1997 return buflen;
2001 * remap_vmalloc_range - map vmalloc pages to userspace
2002 * @vma: vma to cover (map full range of vma)
2003 * @addr: vmalloc memory
2004 * @pgoff: number of pages into addr before first page to map
2006 * Returns: 0 for success, -Exxx on failure
2008 * This function checks that addr is a valid vmalloc'ed area, and
2009 * that it is big enough to cover the vma. Will return failure if
2010 * that criteria isn't met.
2012 * Similar to remap_pfn_range() (see mm/memory.c)
2014 int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
2015 unsigned long pgoff)
2017 struct vm_struct *area;
2018 unsigned long uaddr = vma->vm_start;
2019 unsigned long usize = vma->vm_end - vma->vm_start;
2021 if ((PAGE_SIZE-1) & (unsigned long)addr)
2022 return -EINVAL;
2024 area = find_vm_area(addr);
2025 if (!area)
2026 return -EINVAL;
2028 if (!(area->flags & VM_USERMAP))
2029 return -EINVAL;
2031 if (usize + (pgoff << PAGE_SHIFT) > area->size - PAGE_SIZE)
2032 return -EINVAL;
2034 addr += pgoff << PAGE_SHIFT;
2035 do {
2036 struct page *page = vmalloc_to_page(addr);
2037 int ret;
2039 ret = vm_insert_page(vma, uaddr, page);
2040 if (ret)
2041 return ret;
2043 uaddr += PAGE_SIZE;
2044 addr += PAGE_SIZE;
2045 usize -= PAGE_SIZE;
2046 } while (usize > 0);
2048 /* Prevent "things" like memory migration? VM_flags need a cleanup... */
2049 vma->vm_flags |= VM_RESERVED;
2051 return 0;
2053 EXPORT_SYMBOL(remap_vmalloc_range);
2056 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
2057 * have one.
2059 void __attribute__((weak)) vmalloc_sync_all(void)
2064 static int f(pte_t *pte, pgtable_t table, unsigned long addr, void *data)
2066 /* apply_to_page_range() does all the hard work. */
2067 return 0;
2071 * alloc_vm_area - allocate a range of kernel address space
2072 * @size: size of the area
2074 * Returns: NULL on failure, vm_struct on success
2076 * This function reserves a range of kernel address space, and
2077 * allocates pagetables to map that range. No actual mappings
2078 * are created. If the kernel address space is not shared
2079 * between processes, it syncs the pagetable across all
2080 * processes.
2082 struct vm_struct *alloc_vm_area(size_t size)
2084 struct vm_struct *area;
2086 area = get_vm_area_caller(size, VM_IOREMAP,
2087 __builtin_return_address(0));
2088 if (area == NULL)
2089 return NULL;
2092 * This ensures that page tables are constructed for this region
2093 * of kernel virtual address space and mapped into init_mm.
2095 if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
2096 area->size, f, NULL)) {
2097 free_vm_area(area);
2098 return NULL;
2101 /* Make sure the pagetables are constructed in process kernel
2102 mappings */
2103 vmalloc_sync_all();
2105 return area;
2107 EXPORT_SYMBOL_GPL(alloc_vm_area);
2109 void free_vm_area(struct vm_struct *area)
2111 struct vm_struct *ret;
2112 ret = remove_vm_area(area->addr);
2113 BUG_ON(ret != area);
2114 kfree(area);
2116 EXPORT_SYMBOL_GPL(free_vm_area);
2118 #ifdef CONFIG_SMP
2119 static struct vmap_area *node_to_va(struct rb_node *n)
2121 return n ? rb_entry(n, struct vmap_area, rb_node) : NULL;
2125 * pvm_find_next_prev - find the next and prev vmap_area surrounding @end
2126 * @end: target address
2127 * @pnext: out arg for the next vmap_area
2128 * @pprev: out arg for the previous vmap_area
2130 * Returns: %true if either or both of next and prev are found,
2131 * %false if no vmap_area exists
2133 * Find vmap_areas end addresses of which enclose @end. ie. if not
2134 * NULL, *pnext->va_end > @end and *pprev->va_end <= @end.
2136 static bool pvm_find_next_prev(unsigned long end,
2137 struct vmap_area **pnext,
2138 struct vmap_area **pprev)
2140 struct rb_node *n = vmap_area_root.rb_node;
2141 struct vmap_area *va = NULL;
2143 while (n) {
2144 va = rb_entry(n, struct vmap_area, rb_node);
2145 if (end < va->va_end)
2146 n = n->rb_left;
2147 else if (end > va->va_end)
2148 n = n->rb_right;
2149 else
2150 break;
2153 if (!va)
2154 return false;
2156 if (va->va_end > end) {
2157 *pnext = va;
2158 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2159 } else {
2160 *pprev = va;
2161 *pnext = node_to_va(rb_next(&(*pprev)->rb_node));
2163 return true;
2167 * pvm_determine_end - find the highest aligned address between two vmap_areas
2168 * @pnext: in/out arg for the next vmap_area
2169 * @pprev: in/out arg for the previous vmap_area
2170 * @align: alignment
2172 * Returns: determined end address
2174 * Find the highest aligned address between *@pnext and *@pprev below
2175 * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned
2176 * down address is between the end addresses of the two vmap_areas.
2178 * Please note that the address returned by this function may fall
2179 * inside *@pnext vmap_area. The caller is responsible for checking
2180 * that.
2182 static unsigned long pvm_determine_end(struct vmap_area **pnext,
2183 struct vmap_area **pprev,
2184 unsigned long align)
2186 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2187 unsigned long addr;
2189 if (*pnext)
2190 addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end);
2191 else
2192 addr = vmalloc_end;
2194 while (*pprev && (*pprev)->va_end > addr) {
2195 *pnext = *pprev;
2196 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2199 return addr;
2203 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
2204 * @offsets: array containing offset of each area
2205 * @sizes: array containing size of each area
2206 * @nr_vms: the number of areas to allocate
2207 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
2209 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
2210 * vm_structs on success, %NULL on failure
2212 * Percpu allocator wants to use congruent vm areas so that it can
2213 * maintain the offsets among percpu areas. This function allocates
2214 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
2215 * be scattered pretty far, distance between two areas easily going up
2216 * to gigabytes. To avoid interacting with regular vmallocs, these
2217 * areas are allocated from top.
2219 * Despite its complicated look, this allocator is rather simple. It
2220 * does everything top-down and scans areas from the end looking for
2221 * matching slot. While scanning, if any of the areas overlaps with
2222 * existing vmap_area, the base address is pulled down to fit the
2223 * area. Scanning is repeated till all the areas fit and then all
2224 * necessary data structres are inserted and the result is returned.
2226 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
2227 const size_t *sizes, int nr_vms,
2228 size_t align)
2230 const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
2231 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2232 struct vmap_area **vas, *prev, *next;
2233 struct vm_struct **vms;
2234 int area, area2, last_area, term_area;
2235 unsigned long base, start, end, last_end;
2236 bool purged = false;
2238 /* verify parameters and allocate data structures */
2239 BUG_ON(align & ~PAGE_MASK || !is_power_of_2(align));
2240 for (last_area = 0, area = 0; area < nr_vms; area++) {
2241 start = offsets[area];
2242 end = start + sizes[area];
2244 /* is everything aligned properly? */
2245 BUG_ON(!IS_ALIGNED(offsets[area], align));
2246 BUG_ON(!IS_ALIGNED(sizes[area], align));
2248 /* detect the area with the highest address */
2249 if (start > offsets[last_area])
2250 last_area = area;
2252 for (area2 = 0; area2 < nr_vms; area2++) {
2253 unsigned long start2 = offsets[area2];
2254 unsigned long end2 = start2 + sizes[area2];
2256 if (area2 == area)
2257 continue;
2259 BUG_ON(start2 >= start && start2 < end);
2260 BUG_ON(end2 <= end && end2 > start);
2263 last_end = offsets[last_area] + sizes[last_area];
2265 if (vmalloc_end - vmalloc_start < last_end) {
2266 WARN_ON(true);
2267 return NULL;
2270 vms = kzalloc(sizeof(vms[0]) * nr_vms, GFP_KERNEL);
2271 vas = kzalloc(sizeof(vas[0]) * nr_vms, GFP_KERNEL);
2272 if (!vas || !vms)
2273 goto err_free;
2275 for (area = 0; area < nr_vms; area++) {
2276 vas[area] = kzalloc(sizeof(struct vmap_area), GFP_KERNEL);
2277 vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL);
2278 if (!vas[area] || !vms[area])
2279 goto err_free;
2281 retry:
2282 spin_lock(&vmap_area_lock);
2284 /* start scanning - we scan from the top, begin with the last area */
2285 area = term_area = last_area;
2286 start = offsets[area];
2287 end = start + sizes[area];
2289 if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) {
2290 base = vmalloc_end - last_end;
2291 goto found;
2293 base = pvm_determine_end(&next, &prev, align) - end;
2295 while (true) {
2296 BUG_ON(next && next->va_end <= base + end);
2297 BUG_ON(prev && prev->va_end > base + end);
2300 * base might have underflowed, add last_end before
2301 * comparing.
2303 if (base + last_end < vmalloc_start + last_end) {
2304 spin_unlock(&vmap_area_lock);
2305 if (!purged) {
2306 purge_vmap_area_lazy();
2307 purged = true;
2308 goto retry;
2310 goto err_free;
2314 * If next overlaps, move base downwards so that it's
2315 * right below next and then recheck.
2317 if (next && next->va_start < base + end) {
2318 base = pvm_determine_end(&next, &prev, align) - end;
2319 term_area = area;
2320 continue;
2324 * If prev overlaps, shift down next and prev and move
2325 * base so that it's right below new next and then
2326 * recheck.
2328 if (prev && prev->va_end > base + start) {
2329 next = prev;
2330 prev = node_to_va(rb_prev(&next->rb_node));
2331 base = pvm_determine_end(&next, &prev, align) - end;
2332 term_area = area;
2333 continue;
2337 * This area fits, move on to the previous one. If
2338 * the previous one is the terminal one, we're done.
2340 area = (area + nr_vms - 1) % nr_vms;
2341 if (area == term_area)
2342 break;
2343 start = offsets[area];
2344 end = start + sizes[area];
2345 pvm_find_next_prev(base + end, &next, &prev);
2347 found:
2348 /* we've found a fitting base, insert all va's */
2349 for (area = 0; area < nr_vms; area++) {
2350 struct vmap_area *va = vas[area];
2352 va->va_start = base + offsets[area];
2353 va->va_end = va->va_start + sizes[area];
2354 __insert_vmap_area(va);
2357 vmap_area_pcpu_hole = base + offsets[last_area];
2359 spin_unlock(&vmap_area_lock);
2361 /* insert all vm's */
2362 for (area = 0; area < nr_vms; area++)
2363 insert_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
2364 pcpu_get_vm_areas);
2366 kfree(vas);
2367 return vms;
2369 err_free:
2370 for (area = 0; area < nr_vms; area++) {
2371 if (vas)
2372 kfree(vas[area]);
2373 if (vms)
2374 kfree(vms[area]);
2376 kfree(vas);
2377 kfree(vms);
2378 return NULL;
2382 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
2383 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
2384 * @nr_vms: the number of allocated areas
2386 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
2388 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
2390 int i;
2392 for (i = 0; i < nr_vms; i++)
2393 free_vm_area(vms[i]);
2394 kfree(vms);
2396 #endif /* CONFIG_SMP */
2398 #ifdef CONFIG_PROC_FS
2399 static void *s_start(struct seq_file *m, loff_t *pos)
2400 __acquires(&vmlist_lock)
2402 loff_t n = *pos;
2403 struct vm_struct *v;
2405 read_lock(&vmlist_lock);
2406 v = vmlist;
2407 while (n > 0 && v) {
2408 n--;
2409 v = v->next;
2411 if (!n)
2412 return v;
2414 return NULL;
2418 static void *s_next(struct seq_file *m, void *p, loff_t *pos)
2420 struct vm_struct *v = p;
2422 ++*pos;
2423 return v->next;
2426 static void s_stop(struct seq_file *m, void *p)
2427 __releases(&vmlist_lock)
2429 read_unlock(&vmlist_lock);
2432 static void show_numa_info(struct seq_file *m, struct vm_struct *v)
2434 if (NUMA_BUILD) {
2435 unsigned int nr, *counters = m->private;
2437 if (!counters)
2438 return;
2440 memset(counters, 0, nr_node_ids * sizeof(unsigned int));
2442 for (nr = 0; nr < v->nr_pages; nr++)
2443 counters[page_to_nid(v->pages[nr])]++;
2445 for_each_node_state(nr, N_HIGH_MEMORY)
2446 if (counters[nr])
2447 seq_printf(m, " N%u=%u", nr, counters[nr]);
2451 static int s_show(struct seq_file *m, void *p)
2453 struct vm_struct *v = p;
2455 seq_printf(m, "0x%p-0x%p %7ld",
2456 v->addr, v->addr + v->size, v->size);
2458 if (v->caller)
2459 seq_printf(m, " %pS", v->caller);
2461 if (v->nr_pages)
2462 seq_printf(m, " pages=%d", v->nr_pages);
2464 if (v->phys_addr)
2465 seq_printf(m, " phys=%llx", (unsigned long long)v->phys_addr);
2467 if (v->flags & VM_IOREMAP)
2468 seq_printf(m, " ioremap");
2470 if (v->flags & VM_ALLOC)
2471 seq_printf(m, " vmalloc");
2473 if (v->flags & VM_MAP)
2474 seq_printf(m, " vmap");
2476 if (v->flags & VM_USERMAP)
2477 seq_printf(m, " user");
2479 if (v->flags & VM_VPAGES)
2480 seq_printf(m, " vpages");
2482 show_numa_info(m, v);
2483 seq_putc(m, '\n');
2484 return 0;
2487 static const struct seq_operations vmalloc_op = {
2488 .start = s_start,
2489 .next = s_next,
2490 .stop = s_stop,
2491 .show = s_show,
2494 static int vmalloc_open(struct inode *inode, struct file *file)
2496 unsigned int *ptr = NULL;
2497 int ret;
2499 if (NUMA_BUILD) {
2500 ptr = kmalloc(nr_node_ids * sizeof(unsigned int), GFP_KERNEL);
2501 if (ptr == NULL)
2502 return -ENOMEM;
2504 ret = seq_open(file, &vmalloc_op);
2505 if (!ret) {
2506 struct seq_file *m = file->private_data;
2507 m->private = ptr;
2508 } else
2509 kfree(ptr);
2510 return ret;
2513 static const struct file_operations proc_vmalloc_operations = {
2514 .open = vmalloc_open,
2515 .read = seq_read,
2516 .llseek = seq_lseek,
2517 .release = seq_release_private,
2520 static int __init proc_vmalloc_init(void)
2522 proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
2523 return 0;
2525 module_init(proc_vmalloc_init);
2526 #endif