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
11 #include <linux/vmalloc.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/notifier.h>
25 #include <linux/rbtree.h>
26 #include <linux/radix-tree.h>
27 #include <linux/rcupdate.h>
28 #include <linux/pfn.h>
29 #include <linux/kmemleak.h>
30 #include <linux/atomic.h>
31 #include <linux/compiler.h>
32 #include <linux/llist.h>
33 #include <linux/bitops.h>
35 #include <asm/uaccess.h>
36 #include <asm/tlbflush.h>
37 #include <asm/shmparam.h>
41 struct vfree_deferred {
42 struct llist_head list;
43 struct work_struct wq;
45 static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
47 static void __vunmap(const void *, int);
49 static void free_work(struct work_struct *w)
51 struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
52 struct llist_node *llnode = llist_del_all(&p->list);
55 llnode = llist_next(llnode);
60 /*** Page table manipulation functions ***/
62 static void vunmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end)
66 pte = pte_offset_kernel(pmd, addr);
68 pte_t ptent = ptep_get_and_clear(&init_mm, addr, pte);
69 WARN_ON(!pte_none(ptent) && !pte_present(ptent));
70 } while (pte++, addr += PAGE_SIZE, addr != end);
73 static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end)
78 pmd = pmd_offset(pud, addr);
80 next = pmd_addr_end(addr, end);
81 if (pmd_clear_huge(pmd))
83 if (pmd_none_or_clear_bad(pmd))
85 vunmap_pte_range(pmd, addr, next);
86 } while (pmd++, addr = next, addr != end);
89 static void vunmap_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end)
94 pud = pud_offset(pgd, addr);
96 next = pud_addr_end(addr, end);
97 if (pud_clear_huge(pud))
99 if (pud_none_or_clear_bad(pud))
101 vunmap_pmd_range(pud, addr, next);
102 } while (pud++, addr = next, addr != end);
105 static void vunmap_page_range(unsigned long addr, unsigned long end)
111 pgd = pgd_offset_k(addr);
113 next = pgd_addr_end(addr, end);
114 if (pgd_none_or_clear_bad(pgd))
116 vunmap_pud_range(pgd, addr, next);
117 } while (pgd++, addr = next, addr != end);
120 static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
121 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
126 * nr is a running index into the array which helps higher level
127 * callers keep track of where we're up to.
130 pte = pte_alloc_kernel(pmd, addr);
134 struct page *page = pages[*nr];
136 if (WARN_ON(!pte_none(*pte)))
140 set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
142 } while (pte++, addr += PAGE_SIZE, addr != end);
146 static int vmap_pmd_range(pud_t *pud, unsigned long addr,
147 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
152 pmd = pmd_alloc(&init_mm, pud, addr);
156 next = pmd_addr_end(addr, end);
157 if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
159 } while (pmd++, addr = next, addr != end);
163 static int vmap_pud_range(pgd_t *pgd, unsigned long addr,
164 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
169 pud = pud_alloc(&init_mm, pgd, addr);
173 next = pud_addr_end(addr, end);
174 if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
176 } while (pud++, addr = next, addr != end);
181 * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
182 * will have pfns corresponding to the "pages" array.
184 * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
186 static int vmap_page_range_noflush(unsigned long start, unsigned long end,
187 pgprot_t prot, struct page **pages)
191 unsigned long addr = start;
196 pgd = pgd_offset_k(addr);
198 next = pgd_addr_end(addr, end);
199 err = vmap_pud_range(pgd, addr, next, prot, pages, &nr);
202 } while (pgd++, addr = next, addr != end);
207 static int vmap_page_range(unsigned long start, unsigned long end,
208 pgprot_t prot, struct page **pages)
212 ret = vmap_page_range_noflush(start, end, prot, pages);
213 flush_cache_vmap(start, end);
217 int is_vmalloc_or_module_addr(const void *x)
220 * ARM, x86-64 and sparc64 put modules in a special place,
221 * and fall back on vmalloc() if that fails. Others
222 * just put it in the vmalloc space.
224 #if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
225 unsigned long addr = (unsigned long)x;
226 if (addr >= MODULES_VADDR && addr < MODULES_END)
229 return is_vmalloc_addr(x);
233 * Walk a vmap address to the struct page it maps.
235 struct page *vmalloc_to_page(const void *vmalloc_addr)
237 unsigned long addr = (unsigned long) vmalloc_addr;
238 struct page *page = NULL;
239 pgd_t *pgd = pgd_offset_k(addr);
242 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
243 * architectures that do not vmalloc module space
245 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
247 if (!pgd_none(*pgd)) {
248 pud_t *pud = pud_offset(pgd, addr);
249 if (!pud_none(*pud)) {
250 pmd_t *pmd = pmd_offset(pud, addr);
251 if (!pmd_none(*pmd)) {
254 ptep = pte_offset_map(pmd, addr);
256 if (pte_present(pte))
257 page = pte_page(pte);
264 EXPORT_SYMBOL(vmalloc_to_page);
267 * Map a vmalloc()-space virtual address to the physical page frame number.
269 unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
271 return page_to_pfn(vmalloc_to_page(vmalloc_addr));
273 EXPORT_SYMBOL(vmalloc_to_pfn);
276 /*** Global kva allocator ***/
278 #define VM_LAZY_FREE 0x01
279 #define VM_LAZY_FREEING 0x02
280 #define VM_VM_AREA 0x04
282 static DEFINE_SPINLOCK(vmap_area_lock);
283 /* Export for kexec only */
284 LIST_HEAD(vmap_area_list);
285 static struct rb_root vmap_area_root = RB_ROOT;
287 /* The vmap cache globals are protected by vmap_area_lock */
288 static struct rb_node *free_vmap_cache;
289 static unsigned long cached_hole_size;
290 static unsigned long cached_vstart;
291 static unsigned long cached_align;
293 static unsigned long vmap_area_pcpu_hole;
295 static struct vmap_area *__find_vmap_area(unsigned long addr)
297 struct rb_node *n = vmap_area_root.rb_node;
300 struct vmap_area *va;
302 va = rb_entry(n, struct vmap_area, rb_node);
303 if (addr < va->va_start)
305 else if (addr >= va->va_end)
314 static void __insert_vmap_area(struct vmap_area *va)
316 struct rb_node **p = &vmap_area_root.rb_node;
317 struct rb_node *parent = NULL;
321 struct vmap_area *tmp_va;
324 tmp_va = rb_entry(parent, struct vmap_area, rb_node);
325 if (va->va_start < tmp_va->va_end)
327 else if (va->va_end > tmp_va->va_start)
333 rb_link_node(&va->rb_node, parent, p);
334 rb_insert_color(&va->rb_node, &vmap_area_root);
336 /* address-sort this list */
337 tmp = rb_prev(&va->rb_node);
339 struct vmap_area *prev;
340 prev = rb_entry(tmp, struct vmap_area, rb_node);
341 list_add_rcu(&va->list, &prev->list);
343 list_add_rcu(&va->list, &vmap_area_list);
346 static void purge_vmap_area_lazy(void);
348 static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
351 * Allocate a region of KVA of the specified size and alignment, within the
354 static struct vmap_area *alloc_vmap_area(unsigned long size,
356 unsigned long vstart, unsigned long vend,
357 int node, gfp_t gfp_mask)
359 struct vmap_area *va;
363 struct vmap_area *first;
366 BUG_ON(offset_in_page(size));
367 BUG_ON(!is_power_of_2(align));
369 might_sleep_if(gfpflags_allow_blocking(gfp_mask));
371 va = kmalloc_node(sizeof(struct vmap_area),
372 gfp_mask & GFP_RECLAIM_MASK, node);
374 return ERR_PTR(-ENOMEM);
377 * Only scan the relevant parts containing pointers to other objects
378 * to avoid false negatives.
380 kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask & GFP_RECLAIM_MASK);
383 spin_lock(&vmap_area_lock);
385 * Invalidate cache if we have more permissive parameters.
386 * cached_hole_size notes the largest hole noticed _below_
387 * the vmap_area cached in free_vmap_cache: if size fits
388 * into that hole, we want to scan from vstart to reuse
389 * the hole instead of allocating above free_vmap_cache.
390 * Note that __free_vmap_area may update free_vmap_cache
391 * without updating cached_hole_size or cached_align.
393 if (!free_vmap_cache ||
394 size < cached_hole_size ||
395 vstart < cached_vstart ||
396 align < cached_align) {
398 cached_hole_size = 0;
399 free_vmap_cache = NULL;
401 /* record if we encounter less permissive parameters */
402 cached_vstart = vstart;
403 cached_align = align;
405 /* find starting point for our search */
406 if (free_vmap_cache) {
407 first = rb_entry(free_vmap_cache, struct vmap_area, rb_node);
408 addr = ALIGN(first->va_end, align);
411 if (addr + size < addr)
415 addr = ALIGN(vstart, align);
416 if (addr + size < addr)
419 n = vmap_area_root.rb_node;
423 struct vmap_area *tmp;
424 tmp = rb_entry(n, struct vmap_area, rb_node);
425 if (tmp->va_end >= addr) {
427 if (tmp->va_start <= addr)
438 /* from the starting point, walk areas until a suitable hole is found */
439 while (addr + size > first->va_start && addr + size <= vend) {
440 if (addr + cached_hole_size < first->va_start)
441 cached_hole_size = first->va_start - addr;
442 addr = ALIGN(first->va_end, align);
443 if (addr + size < addr)
446 if (list_is_last(&first->list, &vmap_area_list))
449 first = list_next_entry(first, list);
453 if (addr + size > vend)
457 va->va_end = addr + size;
459 __insert_vmap_area(va);
460 free_vmap_cache = &va->rb_node;
461 spin_unlock(&vmap_area_lock);
463 BUG_ON(!IS_ALIGNED(va->va_start, align));
464 BUG_ON(va->va_start < vstart);
465 BUG_ON(va->va_end > vend);
470 spin_unlock(&vmap_area_lock);
472 purge_vmap_area_lazy();
477 if (gfpflags_allow_blocking(gfp_mask)) {
478 unsigned long freed = 0;
479 blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
486 if (printk_ratelimit())
487 pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
490 return ERR_PTR(-EBUSY);
493 int register_vmap_purge_notifier(struct notifier_block *nb)
495 return blocking_notifier_chain_register(&vmap_notify_list, nb);
497 EXPORT_SYMBOL_GPL(register_vmap_purge_notifier);
499 int unregister_vmap_purge_notifier(struct notifier_block *nb)
501 return blocking_notifier_chain_unregister(&vmap_notify_list, nb);
503 EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
505 static void __free_vmap_area(struct vmap_area *va)
507 BUG_ON(RB_EMPTY_NODE(&va->rb_node));
509 if (free_vmap_cache) {
510 if (va->va_end < cached_vstart) {
511 free_vmap_cache = NULL;
513 struct vmap_area *cache;
514 cache = rb_entry(free_vmap_cache, struct vmap_area, rb_node);
515 if (va->va_start <= cache->va_start) {
516 free_vmap_cache = rb_prev(&va->rb_node);
518 * We don't try to update cached_hole_size or
519 * cached_align, but it won't go very wrong.
524 rb_erase(&va->rb_node, &vmap_area_root);
525 RB_CLEAR_NODE(&va->rb_node);
526 list_del_rcu(&va->list);
529 * Track the highest possible candidate for pcpu area
530 * allocation. Areas outside of vmalloc area can be returned
531 * here too, consider only end addresses which fall inside
532 * vmalloc area proper.
534 if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END)
535 vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end);
537 kfree_rcu(va, rcu_head);
541 * Free a region of KVA allocated by alloc_vmap_area
543 static void free_vmap_area(struct vmap_area *va)
545 spin_lock(&vmap_area_lock);
546 __free_vmap_area(va);
547 spin_unlock(&vmap_area_lock);
551 * Clear the pagetable entries of a given vmap_area
553 static void unmap_vmap_area(struct vmap_area *va)
555 vunmap_page_range(va->va_start, va->va_end);
558 static void vmap_debug_free_range(unsigned long start, unsigned long end)
561 * Unmap page tables and force a TLB flush immediately if pagealloc
562 * debugging is enabled. This catches use after free bugs similarly to
563 * those in linear kernel virtual address space after a page has been
566 * All the lazy freeing logic is still retained, in order to minimise
567 * intrusiveness of this debugging feature.
569 * This is going to be *slow* (linear kernel virtual address debugging
570 * doesn't do a broadcast TLB flush so it is a lot faster).
572 if (debug_pagealloc_enabled()) {
573 vunmap_page_range(start, end);
574 flush_tlb_kernel_range(start, end);
579 * lazy_max_pages is the maximum amount of virtual address space we gather up
580 * before attempting to purge with a TLB flush.
582 * There is a tradeoff here: a larger number will cover more kernel page tables
583 * and take slightly longer to purge, but it will linearly reduce the number of
584 * global TLB flushes that must be performed. It would seem natural to scale
585 * this number up linearly with the number of CPUs (because vmapping activity
586 * could also scale linearly with the number of CPUs), however it is likely
587 * that in practice, workloads might be constrained in other ways that mean
588 * vmap activity will not scale linearly with CPUs. Also, I want to be
589 * conservative and not introduce a big latency on huge systems, so go with
590 * a less aggressive log scale. It will still be an improvement over the old
591 * code, and it will be simple to change the scale factor if we find that it
592 * becomes a problem on bigger systems.
594 static unsigned long lazy_max_pages(void)
598 log = fls(num_online_cpus());
600 return log * (32UL * 1024 * 1024 / PAGE_SIZE);
603 static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
605 /* for per-CPU blocks */
606 static void purge_fragmented_blocks_allcpus(void);
609 * called before a call to iounmap() if the caller wants vm_area_struct's
612 void set_iounmap_nonlazy(void)
614 atomic_set(&vmap_lazy_nr, lazy_max_pages()+1);
618 * Purges all lazily-freed vmap areas.
620 * If sync is 0 then don't purge if there is already a purge in progress.
621 * If force_flush is 1, then flush kernel TLBs between *start and *end even
622 * if we found no lazy vmap areas to unmap (callers can use this to optimise
623 * their own TLB flushing).
624 * Returns with *start = min(*start, lowest purged address)
625 * *end = max(*end, highest purged address)
627 static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
628 int sync, int force_flush)
630 static DEFINE_SPINLOCK(purge_lock);
632 struct vmap_area *va;
633 struct vmap_area *n_va;
637 * If sync is 0 but force_flush is 1, we'll go sync anyway but callers
638 * should not expect such behaviour. This just simplifies locking for
639 * the case that isn't actually used at the moment anyway.
641 if (!sync && !force_flush) {
642 if (!spin_trylock(&purge_lock))
645 spin_lock(&purge_lock);
648 purge_fragmented_blocks_allcpus();
651 list_for_each_entry_rcu(va, &vmap_area_list, list) {
652 if (va->flags & VM_LAZY_FREE) {
653 if (va->va_start < *start)
654 *start = va->va_start;
655 if (va->va_end > *end)
657 nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
658 list_add_tail(&va->purge_list, &valist);
659 va->flags |= VM_LAZY_FREEING;
660 va->flags &= ~VM_LAZY_FREE;
666 atomic_sub(nr, &vmap_lazy_nr);
668 if (nr || force_flush)
669 flush_tlb_kernel_range(*start, *end);
672 spin_lock(&vmap_area_lock);
673 list_for_each_entry_safe(va, n_va, &valist, purge_list)
674 __free_vmap_area(va);
675 spin_unlock(&vmap_area_lock);
677 spin_unlock(&purge_lock);
681 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
682 * is already purging.
684 static void try_purge_vmap_area_lazy(void)
686 unsigned long start = ULONG_MAX, end = 0;
688 __purge_vmap_area_lazy(&start, &end, 0, 0);
692 * Kick off a purge of the outstanding lazy areas.
694 static void purge_vmap_area_lazy(void)
696 unsigned long start = ULONG_MAX, end = 0;
698 __purge_vmap_area_lazy(&start, &end, 1, 0);
702 * Free a vmap area, caller ensuring that the area has been unmapped
703 * and flush_cache_vunmap had been called for the correct range
706 static void free_vmap_area_noflush(struct vmap_area *va)
708 va->flags |= VM_LAZY_FREE;
709 atomic_add((va->va_end - va->va_start) >> PAGE_SHIFT, &vmap_lazy_nr);
710 if (unlikely(atomic_read(&vmap_lazy_nr) > lazy_max_pages()))
711 try_purge_vmap_area_lazy();
715 * Free and unmap a vmap area, caller ensuring flush_cache_vunmap had been
716 * called for the correct range previously.
718 static void free_unmap_vmap_area_noflush(struct vmap_area *va)
721 free_vmap_area_noflush(va);
725 * Free and unmap a vmap area
727 static void free_unmap_vmap_area(struct vmap_area *va)
729 flush_cache_vunmap(va->va_start, va->va_end);
730 free_unmap_vmap_area_noflush(va);
733 static struct vmap_area *find_vmap_area(unsigned long addr)
735 struct vmap_area *va;
737 spin_lock(&vmap_area_lock);
738 va = __find_vmap_area(addr);
739 spin_unlock(&vmap_area_lock);
744 static void free_unmap_vmap_area_addr(unsigned long addr)
746 struct vmap_area *va;
748 va = find_vmap_area(addr);
750 free_unmap_vmap_area(va);
754 /*** Per cpu kva allocator ***/
757 * vmap space is limited especially on 32 bit architectures. Ensure there is
758 * room for at least 16 percpu vmap blocks per CPU.
761 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
762 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
763 * instead (we just need a rough idea)
765 #if BITS_PER_LONG == 32
766 #define VMALLOC_SPACE (128UL*1024*1024)
768 #define VMALLOC_SPACE (128UL*1024*1024*1024)
771 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
772 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
773 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
774 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
775 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
776 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
777 #define VMAP_BBMAP_BITS \
778 VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
779 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
780 VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16))
782 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
784 static bool vmap_initialized __read_mostly = false;
786 struct vmap_block_queue {
788 struct list_head free;
793 struct vmap_area *va;
794 unsigned long free, dirty;
795 unsigned long dirty_min, dirty_max; /*< dirty range */
796 struct list_head free_list;
797 struct rcu_head rcu_head;
798 struct list_head purge;
801 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
802 static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
805 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
806 * in the free path. Could get rid of this if we change the API to return a
807 * "cookie" from alloc, to be passed to free. But no big deal yet.
809 static DEFINE_SPINLOCK(vmap_block_tree_lock);
810 static RADIX_TREE(vmap_block_tree, GFP_ATOMIC);
813 * We should probably have a fallback mechanism to allocate virtual memory
814 * out of partially filled vmap blocks. However vmap block sizing should be
815 * fairly reasonable according to the vmalloc size, so it shouldn't be a
819 static unsigned long addr_to_vb_idx(unsigned long addr)
821 addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
822 addr /= VMAP_BLOCK_SIZE;
826 static void *vmap_block_vaddr(unsigned long va_start, unsigned long pages_off)
830 addr = va_start + (pages_off << PAGE_SHIFT);
831 BUG_ON(addr_to_vb_idx(addr) != addr_to_vb_idx(va_start));
836 * new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
837 * block. Of course pages number can't exceed VMAP_BBMAP_BITS
838 * @order: how many 2^order pages should be occupied in newly allocated block
839 * @gfp_mask: flags for the page level allocator
841 * Returns: virtual address in a newly allocated block or ERR_PTR(-errno)
843 static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
845 struct vmap_block_queue *vbq;
846 struct vmap_block *vb;
847 struct vmap_area *va;
848 unsigned long vb_idx;
852 node = numa_node_id();
854 vb = kmalloc_node(sizeof(struct vmap_block),
855 gfp_mask & GFP_RECLAIM_MASK, node);
857 return ERR_PTR(-ENOMEM);
859 va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
860 VMALLOC_START, VMALLOC_END,
867 err = radix_tree_preload(gfp_mask);
874 vaddr = vmap_block_vaddr(va->va_start, 0);
875 spin_lock_init(&vb->lock);
877 /* At least something should be left free */
878 BUG_ON(VMAP_BBMAP_BITS <= (1UL << order));
879 vb->free = VMAP_BBMAP_BITS - (1UL << order);
881 vb->dirty_min = VMAP_BBMAP_BITS;
883 INIT_LIST_HEAD(&vb->free_list);
885 vb_idx = addr_to_vb_idx(va->va_start);
886 spin_lock(&vmap_block_tree_lock);
887 err = radix_tree_insert(&vmap_block_tree, vb_idx, vb);
888 spin_unlock(&vmap_block_tree_lock);
890 radix_tree_preload_end();
892 vbq = &get_cpu_var(vmap_block_queue);
893 spin_lock(&vbq->lock);
894 list_add_tail_rcu(&vb->free_list, &vbq->free);
895 spin_unlock(&vbq->lock);
896 put_cpu_var(vmap_block_queue);
901 static void free_vmap_block(struct vmap_block *vb)
903 struct vmap_block *tmp;
904 unsigned long vb_idx;
906 vb_idx = addr_to_vb_idx(vb->va->va_start);
907 spin_lock(&vmap_block_tree_lock);
908 tmp = radix_tree_delete(&vmap_block_tree, vb_idx);
909 spin_unlock(&vmap_block_tree_lock);
912 free_vmap_area_noflush(vb->va);
913 kfree_rcu(vb, rcu_head);
916 static void purge_fragmented_blocks(int cpu)
919 struct vmap_block *vb;
920 struct vmap_block *n_vb;
921 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
924 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
926 if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
929 spin_lock(&vb->lock);
930 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
931 vb->free = 0; /* prevent further allocs after releasing lock */
932 vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
934 vb->dirty_max = VMAP_BBMAP_BITS;
935 spin_lock(&vbq->lock);
936 list_del_rcu(&vb->free_list);
937 spin_unlock(&vbq->lock);
938 spin_unlock(&vb->lock);
939 list_add_tail(&vb->purge, &purge);
941 spin_unlock(&vb->lock);
945 list_for_each_entry_safe(vb, n_vb, &purge, purge) {
946 list_del(&vb->purge);
951 static void purge_fragmented_blocks_allcpus(void)
955 for_each_possible_cpu(cpu)
956 purge_fragmented_blocks(cpu);
959 static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
961 struct vmap_block_queue *vbq;
962 struct vmap_block *vb;
966 BUG_ON(offset_in_page(size));
967 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
968 if (WARN_ON(size == 0)) {
970 * Allocating 0 bytes isn't what caller wants since
971 * get_order(0) returns funny result. Just warn and terminate
976 order = get_order(size);
979 vbq = &get_cpu_var(vmap_block_queue);
980 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
981 unsigned long pages_off;
983 spin_lock(&vb->lock);
984 if (vb->free < (1UL << order)) {
985 spin_unlock(&vb->lock);
989 pages_off = VMAP_BBMAP_BITS - vb->free;
990 vaddr = vmap_block_vaddr(vb->va->va_start, pages_off);
991 vb->free -= 1UL << order;
993 spin_lock(&vbq->lock);
994 list_del_rcu(&vb->free_list);
995 spin_unlock(&vbq->lock);
998 spin_unlock(&vb->lock);
1002 put_cpu_var(vmap_block_queue);
1005 /* Allocate new block if nothing was found */
1007 vaddr = new_vmap_block(order, gfp_mask);
1012 static void vb_free(const void *addr, unsigned long size)
1014 unsigned long offset;
1015 unsigned long vb_idx;
1017 struct vmap_block *vb;
1019 BUG_ON(offset_in_page(size));
1020 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
1022 flush_cache_vunmap((unsigned long)addr, (unsigned long)addr + size);
1024 order = get_order(size);
1026 offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1);
1027 offset >>= PAGE_SHIFT;
1029 vb_idx = addr_to_vb_idx((unsigned long)addr);
1031 vb = radix_tree_lookup(&vmap_block_tree, vb_idx);
1035 vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
1037 spin_lock(&vb->lock);
1039 /* Expand dirty range */
1040 vb->dirty_min = min(vb->dirty_min, offset);
1041 vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
1043 vb->dirty += 1UL << order;
1044 if (vb->dirty == VMAP_BBMAP_BITS) {
1046 spin_unlock(&vb->lock);
1047 free_vmap_block(vb);
1049 spin_unlock(&vb->lock);
1053 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
1055 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
1056 * to amortize TLB flushing overheads. What this means is that any page you
1057 * have now, may, in a former life, have been mapped into kernel virtual
1058 * address by the vmap layer and so there might be some CPUs with TLB entries
1059 * still referencing that page (additional to the regular 1:1 kernel mapping).
1061 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
1062 * be sure that none of the pages we have control over will have any aliases
1063 * from the vmap layer.
1065 void vm_unmap_aliases(void)
1067 unsigned long start = ULONG_MAX, end = 0;
1071 if (unlikely(!vmap_initialized))
1074 for_each_possible_cpu(cpu) {
1075 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
1076 struct vmap_block *vb;
1079 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
1080 spin_lock(&vb->lock);
1082 unsigned long va_start = vb->va->va_start;
1085 s = va_start + (vb->dirty_min << PAGE_SHIFT);
1086 e = va_start + (vb->dirty_max << PAGE_SHIFT);
1088 start = min(s, start);
1093 spin_unlock(&vb->lock);
1098 __purge_vmap_area_lazy(&start, &end, 1, flush);
1100 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
1103 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1104 * @mem: the pointer returned by vm_map_ram
1105 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1107 void vm_unmap_ram(const void *mem, unsigned int count)
1109 unsigned long size = count << PAGE_SHIFT;
1110 unsigned long addr = (unsigned long)mem;
1113 BUG_ON(addr < VMALLOC_START);
1114 BUG_ON(addr > VMALLOC_END);
1115 BUG_ON(!PAGE_ALIGNED(addr));
1117 debug_check_no_locks_freed(mem, size);
1118 vmap_debug_free_range(addr, addr+size);
1120 if (likely(count <= VMAP_MAX_ALLOC))
1123 free_unmap_vmap_area_addr(addr);
1125 EXPORT_SYMBOL(vm_unmap_ram);
1128 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1129 * @pages: an array of pointers to the pages to be mapped
1130 * @count: number of pages
1131 * @node: prefer to allocate data structures on this node
1132 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
1134 * If you use this function for less than VMAP_MAX_ALLOC pages, it could be
1135 * faster than vmap so it's good. But if you mix long-life and short-life
1136 * objects with vm_map_ram(), it could consume lots of address space through
1137 * fragmentation (especially on a 32bit machine). You could see failures in
1138 * the end. Please use this function for short-lived objects.
1140 * Returns: a pointer to the address that has been mapped, or %NULL on failure
1142 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
1144 unsigned long size = count << PAGE_SHIFT;
1148 if (likely(count <= VMAP_MAX_ALLOC)) {
1149 mem = vb_alloc(size, GFP_KERNEL);
1152 addr = (unsigned long)mem;
1154 struct vmap_area *va;
1155 va = alloc_vmap_area(size, PAGE_SIZE,
1156 VMALLOC_START, VMALLOC_END, node, GFP_KERNEL);
1160 addr = va->va_start;
1163 if (vmap_page_range(addr, addr + size, prot, pages) < 0) {
1164 vm_unmap_ram(mem, count);
1169 EXPORT_SYMBOL(vm_map_ram);
1171 static struct vm_struct *vmlist __initdata;
1173 * vm_area_add_early - add vmap area early during boot
1174 * @vm: vm_struct to add
1176 * This function is used to add fixed kernel vm area to vmlist before
1177 * vmalloc_init() is called. @vm->addr, @vm->size, and @vm->flags
1178 * should contain proper values and the other fields should be zero.
1180 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1182 void __init vm_area_add_early(struct vm_struct *vm)
1184 struct vm_struct *tmp, **p;
1186 BUG_ON(vmap_initialized);
1187 for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
1188 if (tmp->addr >= vm->addr) {
1189 BUG_ON(tmp->addr < vm->addr + vm->size);
1192 BUG_ON(tmp->addr + tmp->size > vm->addr);
1199 * vm_area_register_early - register vmap area early during boot
1200 * @vm: vm_struct to register
1201 * @align: requested alignment
1203 * This function is used to register kernel vm area before
1204 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1205 * proper values on entry and other fields should be zero. On return,
1206 * vm->addr contains the allocated address.
1208 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1210 void __init vm_area_register_early(struct vm_struct *vm, size_t align)
1212 static size_t vm_init_off __initdata;
1215 addr = ALIGN(VMALLOC_START + vm_init_off, align);
1216 vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START;
1218 vm->addr = (void *)addr;
1220 vm_area_add_early(vm);
1223 void __init vmalloc_init(void)
1225 struct vmap_area *va;
1226 struct vm_struct *tmp;
1229 for_each_possible_cpu(i) {
1230 struct vmap_block_queue *vbq;
1231 struct vfree_deferred *p;
1233 vbq = &per_cpu(vmap_block_queue, i);
1234 spin_lock_init(&vbq->lock);
1235 INIT_LIST_HEAD(&vbq->free);
1236 p = &per_cpu(vfree_deferred, i);
1237 init_llist_head(&p->list);
1238 INIT_WORK(&p->wq, free_work);
1241 /* Import existing vmlist entries. */
1242 for (tmp = vmlist; tmp; tmp = tmp->next) {
1243 va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT);
1244 va->flags = VM_VM_AREA;
1245 va->va_start = (unsigned long)tmp->addr;
1246 va->va_end = va->va_start + tmp->size;
1248 __insert_vmap_area(va);
1251 vmap_area_pcpu_hole = VMALLOC_END;
1253 vmap_initialized = true;
1257 * map_kernel_range_noflush - map kernel VM area with the specified pages
1258 * @addr: start of the VM area to map
1259 * @size: size of the VM area to map
1260 * @prot: page protection flags to use
1261 * @pages: pages to map
1263 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1264 * specify should have been allocated using get_vm_area() and its
1268 * This function does NOT do any cache flushing. The caller is
1269 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1270 * before calling this function.
1273 * The number of pages mapped on success, -errno on failure.
1275 int map_kernel_range_noflush(unsigned long addr, unsigned long size,
1276 pgprot_t prot, struct page **pages)
1278 return vmap_page_range_noflush(addr, addr + size, prot, pages);
1282 * unmap_kernel_range_noflush - unmap kernel VM area
1283 * @addr: start of the VM area to unmap
1284 * @size: size of the VM area to unmap
1286 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1287 * specify should have been allocated using get_vm_area() and its
1291 * This function does NOT do any cache flushing. The caller is
1292 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1293 * before calling this function and flush_tlb_kernel_range() after.
1295 void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
1297 vunmap_page_range(addr, addr + size);
1299 EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush);
1302 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1303 * @addr: start of the VM area to unmap
1304 * @size: size of the VM area to unmap
1306 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1307 * the unmapping and tlb after.
1309 void unmap_kernel_range(unsigned long addr, unsigned long size)
1311 unsigned long end = addr + size;
1313 flush_cache_vunmap(addr, end);
1314 vunmap_page_range(addr, end);
1315 flush_tlb_kernel_range(addr, end);
1317 EXPORT_SYMBOL_GPL(unmap_kernel_range);
1319 int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages)
1321 unsigned long addr = (unsigned long)area->addr;
1322 unsigned long end = addr + get_vm_area_size(area);
1325 err = vmap_page_range(addr, end, prot, pages);
1327 return err > 0 ? 0 : err;
1329 EXPORT_SYMBOL_GPL(map_vm_area);
1331 static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
1332 unsigned long flags, const void *caller)
1334 spin_lock(&vmap_area_lock);
1336 vm->addr = (void *)va->va_start;
1337 vm->size = va->va_end - va->va_start;
1338 vm->caller = caller;
1340 va->flags |= VM_VM_AREA;
1341 spin_unlock(&vmap_area_lock);
1344 static void clear_vm_uninitialized_flag(struct vm_struct *vm)
1347 * Before removing VM_UNINITIALIZED,
1348 * we should make sure that vm has proper values.
1349 * Pair with smp_rmb() in show_numa_info().
1352 vm->flags &= ~VM_UNINITIALIZED;
1355 static struct vm_struct *__get_vm_area_node(unsigned long size,
1356 unsigned long align, unsigned long flags, unsigned long start,
1357 unsigned long end, int node, gfp_t gfp_mask, const void *caller)
1359 struct vmap_area *va;
1360 struct vm_struct *area;
1362 BUG_ON(in_interrupt());
1363 if (flags & VM_IOREMAP)
1364 align = 1ul << clamp_t(int, fls_long(size),
1365 PAGE_SHIFT, IOREMAP_MAX_ORDER);
1367 size = PAGE_ALIGN(size);
1368 if (unlikely(!size))
1371 area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
1372 if (unlikely(!area))
1375 if (!(flags & VM_NO_GUARD))
1378 va = alloc_vmap_area(size, align, start, end, node, gfp_mask);
1384 setup_vmalloc_vm(area, va, flags, caller);
1389 struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
1390 unsigned long start, unsigned long end)
1392 return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE,
1393 GFP_KERNEL, __builtin_return_address(0));
1395 EXPORT_SYMBOL_GPL(__get_vm_area);
1397 struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
1398 unsigned long start, unsigned long end,
1401 return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE,
1402 GFP_KERNEL, caller);
1406 * get_vm_area - reserve a contiguous kernel virtual area
1407 * @size: size of the area
1408 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
1410 * Search an area of @size in the kernel virtual mapping area,
1411 * and reserved it for out purposes. Returns the area descriptor
1412 * on success or %NULL on failure.
1414 struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
1416 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1417 NUMA_NO_NODE, GFP_KERNEL,
1418 __builtin_return_address(0));
1421 struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
1424 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1425 NUMA_NO_NODE, GFP_KERNEL, caller);
1429 * find_vm_area - find a continuous kernel virtual area
1430 * @addr: base address
1432 * Search for the kernel VM area starting at @addr, and return it.
1433 * It is up to the caller to do all required locking to keep the returned
1436 struct vm_struct *find_vm_area(const void *addr)
1438 struct vmap_area *va;
1440 va = find_vmap_area((unsigned long)addr);
1441 if (va && va->flags & VM_VM_AREA)
1448 * remove_vm_area - find and remove a continuous kernel virtual area
1449 * @addr: base address
1451 * Search for the kernel VM area starting at @addr, and remove it.
1452 * This function returns the found VM area, but using it is NOT safe
1453 * on SMP machines, except for its size or flags.
1455 struct vm_struct *remove_vm_area(const void *addr)
1457 struct vmap_area *va;
1459 va = find_vmap_area((unsigned long)addr);
1460 if (va && va->flags & VM_VM_AREA) {
1461 struct vm_struct *vm = va->vm;
1463 spin_lock(&vmap_area_lock);
1465 va->flags &= ~VM_VM_AREA;
1466 spin_unlock(&vmap_area_lock);
1468 vmap_debug_free_range(va->va_start, va->va_end);
1469 kasan_free_shadow(vm);
1470 free_unmap_vmap_area(va);
1477 static void __vunmap(const void *addr, int deallocate_pages)
1479 struct vm_struct *area;
1484 if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
1488 area = remove_vm_area(addr);
1489 if (unlikely(!area)) {
1490 WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
1495 debug_check_no_locks_freed(addr, get_vm_area_size(area));
1496 debug_check_no_obj_freed(addr, get_vm_area_size(area));
1498 if (deallocate_pages) {
1501 for (i = 0; i < area->nr_pages; i++) {
1502 struct page *page = area->pages[i];
1505 __free_kmem_pages(page, 0);
1508 kvfree(area->pages);
1516 * vfree - release memory allocated by vmalloc()
1517 * @addr: memory base address
1519 * Free the virtually continuous memory area starting at @addr, as
1520 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
1521 * NULL, no operation is performed.
1523 * Must not be called in NMI context (strictly speaking, only if we don't
1524 * have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
1525 * conventions for vfree() arch-depenedent would be a really bad idea)
1527 * NOTE: assumes that the object at *addr has a size >= sizeof(llist_node)
1529 void vfree(const void *addr)
1533 kmemleak_free(addr);
1537 if (unlikely(in_interrupt())) {
1538 struct vfree_deferred *p = this_cpu_ptr(&vfree_deferred);
1539 if (llist_add((struct llist_node *)addr, &p->list))
1540 schedule_work(&p->wq);
1544 EXPORT_SYMBOL(vfree);
1547 * vunmap - release virtual mapping obtained by vmap()
1548 * @addr: memory base address
1550 * Free the virtually contiguous memory area starting at @addr,
1551 * which was created from the page array passed to vmap().
1553 * Must not be called in interrupt context.
1555 void vunmap(const void *addr)
1557 BUG_ON(in_interrupt());
1562 EXPORT_SYMBOL(vunmap);
1565 * vmap - map an array of pages into virtually contiguous space
1566 * @pages: array of page pointers
1567 * @count: number of pages to map
1568 * @flags: vm_area->flags
1569 * @prot: page protection for the mapping
1571 * Maps @count pages from @pages into contiguous kernel virtual
1574 void *vmap(struct page **pages, unsigned int count,
1575 unsigned long flags, pgprot_t prot)
1577 struct vm_struct *area;
1581 if (count > totalram_pages)
1584 area = get_vm_area_caller((count << PAGE_SHIFT), flags,
1585 __builtin_return_address(0));
1589 if (map_vm_area(area, prot, pages)) {
1596 EXPORT_SYMBOL(vmap);
1598 static void *__vmalloc_node(unsigned long size, unsigned long align,
1599 gfp_t gfp_mask, pgprot_t prot,
1600 int node, const void *caller);
1601 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
1602 pgprot_t prot, int node)
1604 const int order = 0;
1605 struct page **pages;
1606 unsigned int nr_pages, array_size, i;
1607 const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
1608 const gfp_t alloc_mask = gfp_mask | __GFP_NOWARN;
1610 nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
1611 array_size = (nr_pages * sizeof(struct page *));
1613 area->nr_pages = nr_pages;
1614 /* Please note that the recursion is strictly bounded. */
1615 if (array_size > PAGE_SIZE) {
1616 pages = __vmalloc_node(array_size, 1, nested_gfp|__GFP_HIGHMEM,
1617 PAGE_KERNEL, node, area->caller);
1619 pages = kmalloc_node(array_size, nested_gfp, node);
1621 area->pages = pages;
1623 remove_vm_area(area->addr);
1628 for (i = 0; i < area->nr_pages; i++) {
1631 if (node == NUMA_NO_NODE)
1632 page = alloc_kmem_pages(alloc_mask, order);
1634 page = alloc_kmem_pages_node(node, alloc_mask, order);
1636 if (unlikely(!page)) {
1637 /* Successfully allocated i pages, free them in __vunmap() */
1641 area->pages[i] = page;
1642 if (gfpflags_allow_blocking(gfp_mask))
1646 if (map_vm_area(area, prot, pages))
1651 warn_alloc_failed(gfp_mask, order,
1652 "vmalloc: allocation failure, allocated %ld of %ld bytes\n",
1653 (area->nr_pages*PAGE_SIZE), area->size);
1659 * __vmalloc_node_range - allocate virtually contiguous memory
1660 * @size: allocation size
1661 * @align: desired alignment
1662 * @start: vm area range start
1663 * @end: vm area range end
1664 * @gfp_mask: flags for the page level allocator
1665 * @prot: protection mask for the allocated pages
1666 * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD)
1667 * @node: node to use for allocation or NUMA_NO_NODE
1668 * @caller: caller's return address
1670 * Allocate enough pages to cover @size from the page level
1671 * allocator with @gfp_mask flags. Map them into contiguous
1672 * kernel virtual space, using a pagetable protection of @prot.
1674 void *__vmalloc_node_range(unsigned long size, unsigned long align,
1675 unsigned long start, unsigned long end, gfp_t gfp_mask,
1676 pgprot_t prot, unsigned long vm_flags, int node,
1679 struct vm_struct *area;
1681 unsigned long real_size = size;
1683 size = PAGE_ALIGN(size);
1684 if (!size || (size >> PAGE_SHIFT) > totalram_pages)
1687 area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED |
1688 vm_flags, start, end, node, gfp_mask, caller);
1692 addr = __vmalloc_area_node(area, gfp_mask, prot, node);
1697 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
1698 * flag. It means that vm_struct is not fully initialized.
1699 * Now, it is fully initialized, so remove this flag here.
1701 clear_vm_uninitialized_flag(area);
1704 * A ref_count = 2 is needed because vm_struct allocated in
1705 * __get_vm_area_node() contains a reference to the virtual address of
1706 * the vmalloc'ed block.
1708 kmemleak_alloc(addr, real_size, 2, gfp_mask);
1713 warn_alloc_failed(gfp_mask, 0,
1714 "vmalloc: allocation failure: %lu bytes\n",
1720 * __vmalloc_node - allocate virtually contiguous memory
1721 * @size: allocation size
1722 * @align: desired alignment
1723 * @gfp_mask: flags for the page level allocator
1724 * @prot: protection mask for the allocated pages
1725 * @node: node to use for allocation or NUMA_NO_NODE
1726 * @caller: caller's return address
1728 * Allocate enough pages to cover @size from the page level
1729 * allocator with @gfp_mask flags. Map them into contiguous
1730 * kernel virtual space, using a pagetable protection of @prot.
1732 static void *__vmalloc_node(unsigned long size, unsigned long align,
1733 gfp_t gfp_mask, pgprot_t prot,
1734 int node, const void *caller)
1736 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
1737 gfp_mask, prot, 0, node, caller);
1740 void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
1742 return __vmalloc_node(size, 1, gfp_mask, prot, NUMA_NO_NODE,
1743 __builtin_return_address(0));
1745 EXPORT_SYMBOL(__vmalloc);
1747 static inline void *__vmalloc_node_flags(unsigned long size,
1748 int node, gfp_t flags)
1750 return __vmalloc_node(size, 1, flags, PAGE_KERNEL,
1751 node, __builtin_return_address(0));
1755 * vmalloc - allocate virtually contiguous memory
1756 * @size: allocation size
1757 * Allocate enough pages to cover @size from the page level
1758 * allocator and map them into contiguous kernel virtual space.
1760 * For tight control over page level allocator and protection flags
1761 * use __vmalloc() instead.
1763 void *vmalloc(unsigned long size)
1765 return __vmalloc_node_flags(size, NUMA_NO_NODE,
1766 GFP_KERNEL | __GFP_HIGHMEM);
1768 EXPORT_SYMBOL(vmalloc);
1771 * vzalloc - allocate virtually contiguous memory with zero fill
1772 * @size: allocation size
1773 * Allocate enough pages to cover @size from the page level
1774 * allocator and map them into contiguous kernel virtual space.
1775 * The memory allocated is set to zero.
1777 * For tight control over page level allocator and protection flags
1778 * use __vmalloc() instead.
1780 void *vzalloc(unsigned long size)
1782 return __vmalloc_node_flags(size, NUMA_NO_NODE,
1783 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
1785 EXPORT_SYMBOL(vzalloc);
1788 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
1789 * @size: allocation size
1791 * The resulting memory area is zeroed so it can be mapped to userspace
1792 * without leaking data.
1794 void *vmalloc_user(unsigned long size)
1796 struct vm_struct *area;
1799 ret = __vmalloc_node(size, SHMLBA,
1800 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
1801 PAGE_KERNEL, NUMA_NO_NODE,
1802 __builtin_return_address(0));
1804 area = find_vm_area(ret);
1805 area->flags |= VM_USERMAP;
1809 EXPORT_SYMBOL(vmalloc_user);
1812 * vmalloc_node - allocate memory on a specific node
1813 * @size: allocation size
1816 * Allocate enough pages to cover @size from the page level
1817 * allocator and map them into contiguous kernel virtual space.
1819 * For tight control over page level allocator and protection flags
1820 * use __vmalloc() instead.
1822 void *vmalloc_node(unsigned long size, int node)
1824 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL,
1825 node, __builtin_return_address(0));
1827 EXPORT_SYMBOL(vmalloc_node);
1830 * vzalloc_node - allocate memory on a specific node with zero fill
1831 * @size: allocation size
1834 * Allocate enough pages to cover @size from the page level
1835 * allocator and map them into contiguous kernel virtual space.
1836 * The memory allocated is set to zero.
1838 * For tight control over page level allocator and protection flags
1839 * use __vmalloc_node() instead.
1841 void *vzalloc_node(unsigned long size, int node)
1843 return __vmalloc_node_flags(size, node,
1844 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
1846 EXPORT_SYMBOL(vzalloc_node);
1848 #ifndef PAGE_KERNEL_EXEC
1849 # define PAGE_KERNEL_EXEC PAGE_KERNEL
1853 * vmalloc_exec - allocate virtually contiguous, executable memory
1854 * @size: allocation size
1856 * Kernel-internal function to allocate enough pages to cover @size
1857 * the page level allocator and map them into contiguous and
1858 * executable kernel virtual space.
1860 * For tight control over page level allocator and protection flags
1861 * use __vmalloc() instead.
1864 void *vmalloc_exec(unsigned long size)
1866 return __vmalloc_node(size, 1, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
1867 NUMA_NO_NODE, __builtin_return_address(0));
1870 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
1871 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
1872 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
1873 #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
1875 #define GFP_VMALLOC32 GFP_KERNEL
1879 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
1880 * @size: allocation size
1882 * Allocate enough 32bit PA addressable pages to cover @size from the
1883 * page level allocator and map them into contiguous kernel virtual space.
1885 void *vmalloc_32(unsigned long size)
1887 return __vmalloc_node(size, 1, GFP_VMALLOC32, PAGE_KERNEL,
1888 NUMA_NO_NODE, __builtin_return_address(0));
1890 EXPORT_SYMBOL(vmalloc_32);
1893 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
1894 * @size: allocation size
1896 * The resulting memory area is 32bit addressable and zeroed so it can be
1897 * mapped to userspace without leaking data.
1899 void *vmalloc_32_user(unsigned long size)
1901 struct vm_struct *area;
1904 ret = __vmalloc_node(size, 1, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
1905 NUMA_NO_NODE, __builtin_return_address(0));
1907 area = find_vm_area(ret);
1908 area->flags |= VM_USERMAP;
1912 EXPORT_SYMBOL(vmalloc_32_user);
1915 * small helper routine , copy contents to buf from addr.
1916 * If the page is not present, fill zero.
1919 static int aligned_vread(char *buf, char *addr, unsigned long count)
1925 unsigned long offset, length;
1927 offset = offset_in_page(addr);
1928 length = PAGE_SIZE - offset;
1931 p = vmalloc_to_page(addr);
1933 * To do safe access to this _mapped_ area, we need
1934 * lock. But adding lock here means that we need to add
1935 * overhead of vmalloc()/vfree() calles for this _debug_
1936 * interface, rarely used. Instead of that, we'll use
1937 * kmap() and get small overhead in this access function.
1941 * we can expect USER0 is not used (see vread/vwrite's
1942 * function description)
1944 void *map = kmap_atomic(p);
1945 memcpy(buf, map + offset, length);
1948 memset(buf, 0, length);
1958 static int aligned_vwrite(char *buf, char *addr, unsigned long count)
1964 unsigned long offset, length;
1966 offset = offset_in_page(addr);
1967 length = PAGE_SIZE - offset;
1970 p = vmalloc_to_page(addr);
1972 * To do safe access to this _mapped_ area, we need
1973 * lock. But adding lock here means that we need to add
1974 * overhead of vmalloc()/vfree() calles for this _debug_
1975 * interface, rarely used. Instead of that, we'll use
1976 * kmap() and get small overhead in this access function.
1980 * we can expect USER0 is not used (see vread/vwrite's
1981 * function description)
1983 void *map = kmap_atomic(p);
1984 memcpy(map + offset, buf, length);
1996 * vread() - read vmalloc area in a safe way.
1997 * @buf: buffer for reading data
1998 * @addr: vm address.
1999 * @count: number of bytes to be read.
2001 * Returns # of bytes which addr and buf should be increased.
2002 * (same number to @count). Returns 0 if [addr...addr+count) doesn't
2003 * includes any intersect with alive vmalloc area.
2005 * This function checks that addr is a valid vmalloc'ed area, and
2006 * copy data from that area to a given buffer. If the given memory range
2007 * of [addr...addr+count) includes some valid address, data is copied to
2008 * proper area of @buf. If there are memory holes, they'll be zero-filled.
2009 * IOREMAP area is treated as memory hole and no copy is done.
2011 * If [addr...addr+count) doesn't includes any intersects with alive
2012 * vm_struct area, returns 0. @buf should be kernel's buffer.
2014 * Note: In usual ops, vread() is never necessary because the caller
2015 * should know vmalloc() area is valid and can use memcpy().
2016 * This is for routines which have to access vmalloc area without
2017 * any informaion, as /dev/kmem.
2021 long vread(char *buf, char *addr, unsigned long count)
2023 struct vmap_area *va;
2024 struct vm_struct *vm;
2025 char *vaddr, *buf_start = buf;
2026 unsigned long buflen = count;
2029 /* Don't allow overflow */
2030 if ((unsigned long) addr + count < count)
2031 count = -(unsigned long) addr;
2033 spin_lock(&vmap_area_lock);
2034 list_for_each_entry(va, &vmap_area_list, list) {
2038 if (!(va->flags & VM_VM_AREA))
2042 vaddr = (char *) vm->addr;
2043 if (addr >= vaddr + get_vm_area_size(vm))
2045 while (addr < vaddr) {
2053 n = vaddr + get_vm_area_size(vm) - addr;
2056 if (!(vm->flags & VM_IOREMAP))
2057 aligned_vread(buf, addr, n);
2058 else /* IOREMAP area is treated as memory hole */
2065 spin_unlock(&vmap_area_lock);
2067 if (buf == buf_start)
2069 /* zero-fill memory holes */
2070 if (buf != buf_start + buflen)
2071 memset(buf, 0, buflen - (buf - buf_start));
2077 * vwrite() - write vmalloc area in a safe way.
2078 * @buf: buffer for source data
2079 * @addr: vm address.
2080 * @count: number of bytes to be read.
2082 * Returns # of bytes which addr and buf should be incresed.
2083 * (same number to @count).
2084 * If [addr...addr+count) doesn't includes any intersect with valid
2085 * vmalloc area, returns 0.
2087 * This function checks that addr is a valid vmalloc'ed area, and
2088 * copy data from a buffer to the given addr. If specified range of
2089 * [addr...addr+count) includes some valid address, data is copied from
2090 * proper area of @buf. If there are memory holes, no copy to hole.
2091 * IOREMAP area is treated as memory hole and no copy is done.
2093 * If [addr...addr+count) doesn't includes any intersects with alive
2094 * vm_struct area, returns 0. @buf should be kernel's buffer.
2096 * Note: In usual ops, vwrite() is never necessary because the caller
2097 * should know vmalloc() area is valid and can use memcpy().
2098 * This is for routines which have to access vmalloc area without
2099 * any informaion, as /dev/kmem.
2102 long vwrite(char *buf, char *addr, unsigned long count)
2104 struct vmap_area *va;
2105 struct vm_struct *vm;
2107 unsigned long n, buflen;
2110 /* Don't allow overflow */
2111 if ((unsigned long) addr + count < count)
2112 count = -(unsigned long) addr;
2115 spin_lock(&vmap_area_lock);
2116 list_for_each_entry(va, &vmap_area_list, list) {
2120 if (!(va->flags & VM_VM_AREA))
2124 vaddr = (char *) vm->addr;
2125 if (addr >= vaddr + get_vm_area_size(vm))
2127 while (addr < vaddr) {
2134 n = vaddr + get_vm_area_size(vm) - addr;
2137 if (!(vm->flags & VM_IOREMAP)) {
2138 aligned_vwrite(buf, addr, n);
2146 spin_unlock(&vmap_area_lock);
2153 * remap_vmalloc_range_partial - map vmalloc pages to userspace
2154 * @vma: vma to cover
2155 * @uaddr: target user address to start at
2156 * @kaddr: virtual address of vmalloc kernel memory
2157 * @size: size of map area
2159 * Returns: 0 for success, -Exxx on failure
2161 * This function checks that @kaddr is a valid vmalloc'ed area,
2162 * and that it is big enough to cover the range starting at
2163 * @uaddr in @vma. Will return failure if that criteria isn't
2166 * Similar to remap_pfn_range() (see mm/memory.c)
2168 int remap_vmalloc_range_partial(struct vm_area_struct *vma, unsigned long uaddr,
2169 void *kaddr, unsigned long size)
2171 struct vm_struct *area;
2173 size = PAGE_ALIGN(size);
2175 if (!PAGE_ALIGNED(uaddr) || !PAGE_ALIGNED(kaddr))
2178 area = find_vm_area(kaddr);
2182 if (!(area->flags & VM_USERMAP))
2185 if (kaddr + size > area->addr + area->size)
2189 struct page *page = vmalloc_to_page(kaddr);
2192 ret = vm_insert_page(vma, uaddr, page);
2201 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
2205 EXPORT_SYMBOL(remap_vmalloc_range_partial);
2208 * remap_vmalloc_range - map vmalloc pages to userspace
2209 * @vma: vma to cover (map full range of vma)
2210 * @addr: vmalloc memory
2211 * @pgoff: number of pages into addr before first page to map
2213 * Returns: 0 for success, -Exxx on failure
2215 * This function checks that addr is a valid vmalloc'ed area, and
2216 * that it is big enough to cover the vma. Will return failure if
2217 * that criteria isn't met.
2219 * Similar to remap_pfn_range() (see mm/memory.c)
2221 int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
2222 unsigned long pgoff)
2224 return remap_vmalloc_range_partial(vma, vma->vm_start,
2225 addr + (pgoff << PAGE_SHIFT),
2226 vma->vm_end - vma->vm_start);
2228 EXPORT_SYMBOL(remap_vmalloc_range);
2231 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
2234 void __weak vmalloc_sync_all(void)
2239 static int f(pte_t *pte, pgtable_t table, unsigned long addr, void *data)
2251 * alloc_vm_area - allocate a range of kernel address space
2252 * @size: size of the area
2253 * @ptes: returns the PTEs for the address space
2255 * Returns: NULL on failure, vm_struct on success
2257 * This function reserves a range of kernel address space, and
2258 * allocates pagetables to map that range. No actual mappings
2261 * If @ptes is non-NULL, pointers to the PTEs (in init_mm)
2262 * allocated for the VM area are returned.
2264 struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
2266 struct vm_struct *area;
2268 area = get_vm_area_caller(size, VM_IOREMAP,
2269 __builtin_return_address(0));
2274 * This ensures that page tables are constructed for this region
2275 * of kernel virtual address space and mapped into init_mm.
2277 if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
2278 size, f, ptes ? &ptes : NULL)) {
2285 EXPORT_SYMBOL_GPL(alloc_vm_area);
2287 void free_vm_area(struct vm_struct *area)
2289 struct vm_struct *ret;
2290 ret = remove_vm_area(area->addr);
2291 BUG_ON(ret != area);
2294 EXPORT_SYMBOL_GPL(free_vm_area);
2297 static struct vmap_area *node_to_va(struct rb_node *n)
2299 return n ? rb_entry(n, struct vmap_area, rb_node) : NULL;
2303 * pvm_find_next_prev - find the next and prev vmap_area surrounding @end
2304 * @end: target address
2305 * @pnext: out arg for the next vmap_area
2306 * @pprev: out arg for the previous vmap_area
2308 * Returns: %true if either or both of next and prev are found,
2309 * %false if no vmap_area exists
2311 * Find vmap_areas end addresses of which enclose @end. ie. if not
2312 * NULL, *pnext->va_end > @end and *pprev->va_end <= @end.
2314 static bool pvm_find_next_prev(unsigned long end,
2315 struct vmap_area **pnext,
2316 struct vmap_area **pprev)
2318 struct rb_node *n = vmap_area_root.rb_node;
2319 struct vmap_area *va = NULL;
2322 va = rb_entry(n, struct vmap_area, rb_node);
2323 if (end < va->va_end)
2325 else if (end > va->va_end)
2334 if (va->va_end > end) {
2336 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2339 *pnext = node_to_va(rb_next(&(*pprev)->rb_node));
2345 * pvm_determine_end - find the highest aligned address between two vmap_areas
2346 * @pnext: in/out arg for the next vmap_area
2347 * @pprev: in/out arg for the previous vmap_area
2350 * Returns: determined end address
2352 * Find the highest aligned address between *@pnext and *@pprev below
2353 * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned
2354 * down address is between the end addresses of the two vmap_areas.
2356 * Please note that the address returned by this function may fall
2357 * inside *@pnext vmap_area. The caller is responsible for checking
2360 static unsigned long pvm_determine_end(struct vmap_area **pnext,
2361 struct vmap_area **pprev,
2362 unsigned long align)
2364 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2368 addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end);
2372 while (*pprev && (*pprev)->va_end > addr) {
2374 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2381 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
2382 * @offsets: array containing offset of each area
2383 * @sizes: array containing size of each area
2384 * @nr_vms: the number of areas to allocate
2385 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
2387 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
2388 * vm_structs on success, %NULL on failure
2390 * Percpu allocator wants to use congruent vm areas so that it can
2391 * maintain the offsets among percpu areas. This function allocates
2392 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
2393 * be scattered pretty far, distance between two areas easily going up
2394 * to gigabytes. To avoid interacting with regular vmallocs, these
2395 * areas are allocated from top.
2397 * Despite its complicated look, this allocator is rather simple. It
2398 * does everything top-down and scans areas from the end looking for
2399 * matching slot. While scanning, if any of the areas overlaps with
2400 * existing vmap_area, the base address is pulled down to fit the
2401 * area. Scanning is repeated till all the areas fit and then all
2402 * necessary data structres are inserted and the result is returned.
2404 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
2405 const size_t *sizes, int nr_vms,
2408 const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
2409 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2410 struct vmap_area **vas, *prev, *next;
2411 struct vm_struct **vms;
2412 int area, area2, last_area, term_area;
2413 unsigned long base, start, end, last_end;
2414 bool purged = false;
2416 /* verify parameters and allocate data structures */
2417 BUG_ON(offset_in_page(align) || !is_power_of_2(align));
2418 for (last_area = 0, area = 0; area < nr_vms; area++) {
2419 start = offsets[area];
2420 end = start + sizes[area];
2422 /* is everything aligned properly? */
2423 BUG_ON(!IS_ALIGNED(offsets[area], align));
2424 BUG_ON(!IS_ALIGNED(sizes[area], align));
2426 /* detect the area with the highest address */
2427 if (start > offsets[last_area])
2430 for (area2 = 0; area2 < nr_vms; area2++) {
2431 unsigned long start2 = offsets[area2];
2432 unsigned long end2 = start2 + sizes[area2];
2437 BUG_ON(start2 >= start && start2 < end);
2438 BUG_ON(end2 <= end && end2 > start);
2441 last_end = offsets[last_area] + sizes[last_area];
2443 if (vmalloc_end - vmalloc_start < last_end) {
2448 vms = kcalloc(nr_vms, sizeof(vms[0]), GFP_KERNEL);
2449 vas = kcalloc(nr_vms, sizeof(vas[0]), GFP_KERNEL);
2453 for (area = 0; area < nr_vms; area++) {
2454 vas[area] = kzalloc(sizeof(struct vmap_area), GFP_KERNEL);
2455 vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL);
2456 if (!vas[area] || !vms[area])
2460 spin_lock(&vmap_area_lock);
2462 /* start scanning - we scan from the top, begin with the last area */
2463 area = term_area = last_area;
2464 start = offsets[area];
2465 end = start + sizes[area];
2467 if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) {
2468 base = vmalloc_end - last_end;
2471 base = pvm_determine_end(&next, &prev, align) - end;
2474 BUG_ON(next && next->va_end <= base + end);
2475 BUG_ON(prev && prev->va_end > base + end);
2478 * base might have underflowed, add last_end before
2481 if (base + last_end < vmalloc_start + last_end) {
2482 spin_unlock(&vmap_area_lock);
2484 purge_vmap_area_lazy();
2492 * If next overlaps, move base downwards so that it's
2493 * right below next and then recheck.
2495 if (next && next->va_start < base + end) {
2496 base = pvm_determine_end(&next, &prev, align) - end;
2502 * If prev overlaps, shift down next and prev and move
2503 * base so that it's right below new next and then
2506 if (prev && prev->va_end > base + start) {
2508 prev = node_to_va(rb_prev(&next->rb_node));
2509 base = pvm_determine_end(&next, &prev, align) - end;
2515 * This area fits, move on to the previous one. If
2516 * the previous one is the terminal one, we're done.
2518 area = (area + nr_vms - 1) % nr_vms;
2519 if (area == term_area)
2521 start = offsets[area];
2522 end = start + sizes[area];
2523 pvm_find_next_prev(base + end, &next, &prev);
2526 /* we've found a fitting base, insert all va's */
2527 for (area = 0; area < nr_vms; area++) {
2528 struct vmap_area *va = vas[area];
2530 va->va_start = base + offsets[area];
2531 va->va_end = va->va_start + sizes[area];
2532 __insert_vmap_area(va);
2535 vmap_area_pcpu_hole = base + offsets[last_area];
2537 spin_unlock(&vmap_area_lock);
2539 /* insert all vm's */
2540 for (area = 0; area < nr_vms; area++)
2541 setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
2548 for (area = 0; area < nr_vms; area++) {
2559 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
2560 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
2561 * @nr_vms: the number of allocated areas
2563 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
2565 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
2569 for (i = 0; i < nr_vms; i++)
2570 free_vm_area(vms[i]);
2573 #endif /* CONFIG_SMP */
2575 #ifdef CONFIG_PROC_FS
2576 static void *s_start(struct seq_file *m, loff_t *pos)
2577 __acquires(&vmap_area_lock)
2580 struct vmap_area *va;
2582 spin_lock(&vmap_area_lock);
2583 va = list_first_entry(&vmap_area_list, typeof(*va), list);
2584 while (n > 0 && &va->list != &vmap_area_list) {
2586 va = list_next_entry(va, list);
2588 if (!n && &va->list != &vmap_area_list)
2595 static void *s_next(struct seq_file *m, void *p, loff_t *pos)
2597 struct vmap_area *va = p, *next;
2600 next = list_next_entry(va, list);
2601 if (&next->list != &vmap_area_list)
2607 static void s_stop(struct seq_file *m, void *p)
2608 __releases(&vmap_area_lock)
2610 spin_unlock(&vmap_area_lock);
2613 static void show_numa_info(struct seq_file *m, struct vm_struct *v)
2615 if (IS_ENABLED(CONFIG_NUMA)) {
2616 unsigned int nr, *counters = m->private;
2621 if (v->flags & VM_UNINITIALIZED)
2623 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
2626 memset(counters, 0, nr_node_ids * sizeof(unsigned int));
2628 for (nr = 0; nr < v->nr_pages; nr++)
2629 counters[page_to_nid(v->pages[nr])]++;
2631 for_each_node_state(nr, N_HIGH_MEMORY)
2633 seq_printf(m, " N%u=%u", nr, counters[nr]);
2637 static int s_show(struct seq_file *m, void *p)
2639 struct vmap_area *va = p;
2640 struct vm_struct *v;
2643 * s_show can encounter race with remove_vm_area, !VM_VM_AREA on
2644 * behalf of vmap area is being tear down or vm_map_ram allocation.
2646 if (!(va->flags & VM_VM_AREA))
2651 seq_printf(m, "0x%pK-0x%pK %7ld",
2652 v->addr, v->addr + v->size, v->size);
2655 seq_printf(m, " %pS", v->caller);
2658 seq_printf(m, " pages=%d", v->nr_pages);
2661 seq_printf(m, " phys=%llx", (unsigned long long)v->phys_addr);
2663 if (v->flags & VM_IOREMAP)
2664 seq_puts(m, " ioremap");
2666 if (v->flags & VM_ALLOC)
2667 seq_puts(m, " vmalloc");
2669 if (v->flags & VM_MAP)
2670 seq_puts(m, " vmap");
2672 if (v->flags & VM_USERMAP)
2673 seq_puts(m, " user");
2675 if (is_vmalloc_addr(v->pages))
2676 seq_puts(m, " vpages");
2678 show_numa_info(m, v);
2683 static const struct seq_operations vmalloc_op = {
2690 static int vmalloc_open(struct inode *inode, struct file *file)
2692 if (IS_ENABLED(CONFIG_NUMA))
2693 return seq_open_private(file, &vmalloc_op,
2694 nr_node_ids * sizeof(unsigned int));
2696 return seq_open(file, &vmalloc_op);
2699 static const struct file_operations proc_vmalloc_operations = {
2700 .open = vmalloc_open,
2702 .llseek = seq_lseek,
2703 .release = seq_release_private,
2706 static int __init proc_vmalloc_init(void)
2708 proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
2711 module_init(proc_vmalloc_init);