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/signal.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 <linux/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(p4d_t *p4d, unsigned long addr, unsigned long end)
94 pud = pud_offset(p4d, 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_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end)
110 p4d = p4d_offset(pgd, addr);
112 next = p4d_addr_end(addr, end);
113 if (p4d_clear_huge(p4d))
115 if (p4d_none_or_clear_bad(p4d))
117 vunmap_pud_range(p4d, addr, next);
118 } while (p4d++, addr = next, addr != end);
121 static void vunmap_page_range(unsigned long addr, unsigned long end)
127 pgd = pgd_offset_k(addr);
129 next = pgd_addr_end(addr, end);
130 if (pgd_none_or_clear_bad(pgd))
132 vunmap_p4d_range(pgd, addr, next);
133 } while (pgd++, addr = next, addr != end);
136 static int vmap_pte_range(pmd_t *pmd, unsigned long addr,
137 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
142 * nr is a running index into the array which helps higher level
143 * callers keep track of where we're up to.
146 pte = pte_alloc_kernel(pmd, addr);
150 struct page *page = pages[*nr];
152 if (WARN_ON(!pte_none(*pte)))
156 set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
158 } while (pte++, addr += PAGE_SIZE, addr != end);
162 static int vmap_pmd_range(pud_t *pud, unsigned long addr,
163 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
168 pmd = pmd_alloc(&init_mm, pud, addr);
172 next = pmd_addr_end(addr, end);
173 if (vmap_pte_range(pmd, addr, next, prot, pages, nr))
175 } while (pmd++, addr = next, addr != end);
179 static int vmap_pud_range(p4d_t *p4d, unsigned long addr,
180 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
185 pud = pud_alloc(&init_mm, p4d, addr);
189 next = pud_addr_end(addr, end);
190 if (vmap_pmd_range(pud, addr, next, prot, pages, nr))
192 } while (pud++, addr = next, addr != end);
196 static int vmap_p4d_range(pgd_t *pgd, unsigned long addr,
197 unsigned long end, pgprot_t prot, struct page **pages, int *nr)
202 p4d = p4d_alloc(&init_mm, pgd, addr);
206 next = p4d_addr_end(addr, end);
207 if (vmap_pud_range(p4d, addr, next, prot, pages, nr))
209 } while (p4d++, addr = next, addr != end);
214 * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
215 * will have pfns corresponding to the "pages" array.
217 * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
219 static int vmap_page_range_noflush(unsigned long start, unsigned long end,
220 pgprot_t prot, struct page **pages)
224 unsigned long addr = start;
229 pgd = pgd_offset_k(addr);
231 next = pgd_addr_end(addr, end);
232 err = vmap_p4d_range(pgd, addr, next, prot, pages, &nr);
235 } while (pgd++, addr = next, addr != end);
240 static int vmap_page_range(unsigned long start, unsigned long end,
241 pgprot_t prot, struct page **pages)
245 ret = vmap_page_range_noflush(start, end, prot, pages);
246 flush_cache_vmap(start, end);
250 int is_vmalloc_or_module_addr(const void *x)
253 * ARM, x86-64 and sparc64 put modules in a special place,
254 * and fall back on vmalloc() if that fails. Others
255 * just put it in the vmalloc space.
257 #if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
258 unsigned long addr = (unsigned long)x;
259 if (addr >= MODULES_VADDR && addr < MODULES_END)
262 return is_vmalloc_addr(x);
266 * Walk a vmap address to the struct page it maps.
268 struct page *vmalloc_to_page(const void *vmalloc_addr)
270 unsigned long addr = (unsigned long) vmalloc_addr;
271 struct page *page = NULL;
272 pgd_t *pgd = pgd_offset_k(addr);
279 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
280 * architectures that do not vmalloc module space
282 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
286 p4d = p4d_offset(pgd, addr);
289 pud = pud_offset(p4d, addr);
292 * Don't dereference bad PUD or PMD (below) entries. This will also
293 * identify huge mappings, which we may encounter on architectures
294 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
295 * identified as vmalloc addresses by is_vmalloc_addr(), but are
296 * not [unambiguously] associated with a struct page, so there is
297 * no correct value to return for them.
299 WARN_ON_ONCE(pud_bad(*pud));
300 if (pud_none(*pud) || pud_bad(*pud))
302 pmd = pmd_offset(pud, addr);
303 WARN_ON_ONCE(pmd_bad(*pmd));
304 if (pmd_none(*pmd) || pmd_bad(*pmd))
307 ptep = pte_offset_map(pmd, addr);
309 if (pte_present(pte))
310 page = pte_page(pte);
314 EXPORT_SYMBOL(vmalloc_to_page);
317 * Map a vmalloc()-space virtual address to the physical page frame number.
319 unsigned long vmalloc_to_pfn(const void *vmalloc_addr)
321 return page_to_pfn(vmalloc_to_page(vmalloc_addr));
323 EXPORT_SYMBOL(vmalloc_to_pfn);
326 /*** Global kva allocator ***/
328 #define VM_VM_AREA 0x04
330 static DEFINE_SPINLOCK(vmap_area_lock);
331 /* Export for kexec only */
332 LIST_HEAD(vmap_area_list);
333 static LLIST_HEAD(vmap_purge_list);
334 static struct rb_root vmap_area_root = RB_ROOT;
336 /* The vmap cache globals are protected by vmap_area_lock */
337 static struct rb_node *free_vmap_cache;
338 static unsigned long cached_hole_size;
339 static unsigned long cached_vstart;
340 static unsigned long cached_align;
342 static unsigned long vmap_area_pcpu_hole;
344 static struct vmap_area *__find_vmap_area(unsigned long addr)
346 struct rb_node *n = vmap_area_root.rb_node;
349 struct vmap_area *va;
351 va = rb_entry(n, struct vmap_area, rb_node);
352 if (addr < va->va_start)
354 else if (addr >= va->va_end)
363 static void __insert_vmap_area(struct vmap_area *va)
365 struct rb_node **p = &vmap_area_root.rb_node;
366 struct rb_node *parent = NULL;
370 struct vmap_area *tmp_va;
373 tmp_va = rb_entry(parent, struct vmap_area, rb_node);
374 if (va->va_start < tmp_va->va_end)
376 else if (va->va_end > tmp_va->va_start)
382 rb_link_node(&va->rb_node, parent, p);
383 rb_insert_color(&va->rb_node, &vmap_area_root);
385 /* address-sort this list */
386 tmp = rb_prev(&va->rb_node);
388 struct vmap_area *prev;
389 prev = rb_entry(tmp, struct vmap_area, rb_node);
390 list_add_rcu(&va->list, &prev->list);
392 list_add_rcu(&va->list, &vmap_area_list);
395 static void purge_vmap_area_lazy(void);
397 static BLOCKING_NOTIFIER_HEAD(vmap_notify_list);
400 * Allocate a region of KVA of the specified size and alignment, within the
403 static struct vmap_area *alloc_vmap_area(unsigned long size,
405 unsigned long vstart, unsigned long vend,
406 int node, gfp_t gfp_mask)
408 struct vmap_area *va;
412 struct vmap_area *first;
415 BUG_ON(offset_in_page(size));
416 BUG_ON(!is_power_of_2(align));
420 va = kmalloc_node(sizeof(struct vmap_area),
421 gfp_mask & GFP_RECLAIM_MASK, node);
423 return ERR_PTR(-ENOMEM);
426 * Only scan the relevant parts containing pointers to other objects
427 * to avoid false negatives.
429 kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask & GFP_RECLAIM_MASK);
432 spin_lock(&vmap_area_lock);
434 * Invalidate cache if we have more permissive parameters.
435 * cached_hole_size notes the largest hole noticed _below_
436 * the vmap_area cached in free_vmap_cache: if size fits
437 * into that hole, we want to scan from vstart to reuse
438 * the hole instead of allocating above free_vmap_cache.
439 * Note that __free_vmap_area may update free_vmap_cache
440 * without updating cached_hole_size or cached_align.
442 if (!free_vmap_cache ||
443 size < cached_hole_size ||
444 vstart < cached_vstart ||
445 align < cached_align) {
447 cached_hole_size = 0;
448 free_vmap_cache = NULL;
450 /* record if we encounter less permissive parameters */
451 cached_vstart = vstart;
452 cached_align = align;
454 /* find starting point for our search */
455 if (free_vmap_cache) {
456 first = rb_entry(free_vmap_cache, struct vmap_area, rb_node);
457 addr = ALIGN(first->va_end, align);
460 if (addr + size < addr)
464 addr = ALIGN(vstart, align);
465 if (addr + size < addr)
468 n = vmap_area_root.rb_node;
472 struct vmap_area *tmp;
473 tmp = rb_entry(n, struct vmap_area, rb_node);
474 if (tmp->va_end >= addr) {
476 if (tmp->va_start <= addr)
487 /* from the starting point, walk areas until a suitable hole is found */
488 while (addr + size > first->va_start && addr + size <= vend) {
489 if (addr + cached_hole_size < first->va_start)
490 cached_hole_size = first->va_start - addr;
491 addr = ALIGN(first->va_end, align);
492 if (addr + size < addr)
495 if (list_is_last(&first->list, &vmap_area_list))
498 first = list_next_entry(first, list);
502 if (addr + size > vend)
506 va->va_end = addr + size;
508 __insert_vmap_area(va);
509 free_vmap_cache = &va->rb_node;
510 spin_unlock(&vmap_area_lock);
512 BUG_ON(!IS_ALIGNED(va->va_start, align));
513 BUG_ON(va->va_start < vstart);
514 BUG_ON(va->va_end > vend);
519 spin_unlock(&vmap_area_lock);
521 purge_vmap_area_lazy();
526 if (gfpflags_allow_blocking(gfp_mask)) {
527 unsigned long freed = 0;
528 blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
535 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit())
536 pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
539 return ERR_PTR(-EBUSY);
542 int register_vmap_purge_notifier(struct notifier_block *nb)
544 return blocking_notifier_chain_register(&vmap_notify_list, nb);
546 EXPORT_SYMBOL_GPL(register_vmap_purge_notifier);
548 int unregister_vmap_purge_notifier(struct notifier_block *nb)
550 return blocking_notifier_chain_unregister(&vmap_notify_list, nb);
552 EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
554 static void __free_vmap_area(struct vmap_area *va)
556 BUG_ON(RB_EMPTY_NODE(&va->rb_node));
558 if (free_vmap_cache) {
559 if (va->va_end < cached_vstart) {
560 free_vmap_cache = NULL;
562 struct vmap_area *cache;
563 cache = rb_entry(free_vmap_cache, struct vmap_area, rb_node);
564 if (va->va_start <= cache->va_start) {
565 free_vmap_cache = rb_prev(&va->rb_node);
567 * We don't try to update cached_hole_size or
568 * cached_align, but it won't go very wrong.
573 rb_erase(&va->rb_node, &vmap_area_root);
574 RB_CLEAR_NODE(&va->rb_node);
575 list_del_rcu(&va->list);
578 * Track the highest possible candidate for pcpu area
579 * allocation. Areas outside of vmalloc area can be returned
580 * here too, consider only end addresses which fall inside
581 * vmalloc area proper.
583 if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END)
584 vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end);
586 kfree_rcu(va, rcu_head);
590 * Free a region of KVA allocated by alloc_vmap_area
592 static void free_vmap_area(struct vmap_area *va)
594 spin_lock(&vmap_area_lock);
595 __free_vmap_area(va);
596 spin_unlock(&vmap_area_lock);
600 * Clear the pagetable entries of a given vmap_area
602 static void unmap_vmap_area(struct vmap_area *va)
604 vunmap_page_range(va->va_start, va->va_end);
607 static void vmap_debug_free_range(unsigned long start, unsigned long end)
610 * Unmap page tables and force a TLB flush immediately if pagealloc
611 * debugging is enabled. This catches use after free bugs similarly to
612 * those in linear kernel virtual address space after a page has been
615 * All the lazy freeing logic is still retained, in order to minimise
616 * intrusiveness of this debugging feature.
618 * This is going to be *slow* (linear kernel virtual address debugging
619 * doesn't do a broadcast TLB flush so it is a lot faster).
621 if (debug_pagealloc_enabled()) {
622 vunmap_page_range(start, end);
623 flush_tlb_kernel_range(start, end);
628 * lazy_max_pages is the maximum amount of virtual address space we gather up
629 * before attempting to purge with a TLB flush.
631 * There is a tradeoff here: a larger number will cover more kernel page tables
632 * and take slightly longer to purge, but it will linearly reduce the number of
633 * global TLB flushes that must be performed. It would seem natural to scale
634 * this number up linearly with the number of CPUs (because vmapping activity
635 * could also scale linearly with the number of CPUs), however it is likely
636 * that in practice, workloads might be constrained in other ways that mean
637 * vmap activity will not scale linearly with CPUs. Also, I want to be
638 * conservative and not introduce a big latency on huge systems, so go with
639 * a less aggressive log scale. It will still be an improvement over the old
640 * code, and it will be simple to change the scale factor if we find that it
641 * becomes a problem on bigger systems.
643 static unsigned long lazy_max_pages(void)
647 log = fls(num_online_cpus());
649 return log * (32UL * 1024 * 1024 / PAGE_SIZE);
652 static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
655 * Serialize vmap purging. There is no actual criticial section protected
656 * by this look, but we want to avoid concurrent calls for performance
657 * reasons and to make the pcpu_get_vm_areas more deterministic.
659 static DEFINE_MUTEX(vmap_purge_lock);
661 /* for per-CPU blocks */
662 static void purge_fragmented_blocks_allcpus(void);
665 * called before a call to iounmap() if the caller wants vm_area_struct's
668 void set_iounmap_nonlazy(void)
670 atomic_set(&vmap_lazy_nr, lazy_max_pages()+1);
674 * Purges all lazily-freed vmap areas.
676 static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
678 struct llist_node *valist;
679 struct vmap_area *va;
680 struct vmap_area *n_va;
681 bool do_free = false;
683 lockdep_assert_held(&vmap_purge_lock);
685 valist = llist_del_all(&vmap_purge_list);
686 llist_for_each_entry(va, valist, purge_list) {
687 if (va->va_start < start)
688 start = va->va_start;
689 if (va->va_end > end)
697 flush_tlb_kernel_range(start, end);
699 spin_lock(&vmap_area_lock);
700 llist_for_each_entry_safe(va, n_va, valist, purge_list) {
701 int nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
703 __free_vmap_area(va);
704 atomic_sub(nr, &vmap_lazy_nr);
705 cond_resched_lock(&vmap_area_lock);
707 spin_unlock(&vmap_area_lock);
712 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
713 * is already purging.
715 static void try_purge_vmap_area_lazy(void)
717 if (mutex_trylock(&vmap_purge_lock)) {
718 __purge_vmap_area_lazy(ULONG_MAX, 0);
719 mutex_unlock(&vmap_purge_lock);
724 * Kick off a purge of the outstanding lazy areas.
726 static void purge_vmap_area_lazy(void)
728 mutex_lock(&vmap_purge_lock);
729 purge_fragmented_blocks_allcpus();
730 __purge_vmap_area_lazy(ULONG_MAX, 0);
731 mutex_unlock(&vmap_purge_lock);
735 * Free a vmap area, caller ensuring that the area has been unmapped
736 * and flush_cache_vunmap had been called for the correct range
739 static void free_vmap_area_noflush(struct vmap_area *va)
743 nr_lazy = atomic_add_return((va->va_end - va->va_start) >> PAGE_SHIFT,
746 /* After this point, we may free va at any time */
747 llist_add(&va->purge_list, &vmap_purge_list);
749 if (unlikely(nr_lazy > lazy_max_pages()))
750 try_purge_vmap_area_lazy();
754 * Free and unmap a vmap area
756 static void free_unmap_vmap_area(struct vmap_area *va)
758 flush_cache_vunmap(va->va_start, va->va_end);
760 free_vmap_area_noflush(va);
763 static struct vmap_area *find_vmap_area(unsigned long addr)
765 struct vmap_area *va;
767 spin_lock(&vmap_area_lock);
768 va = __find_vmap_area(addr);
769 spin_unlock(&vmap_area_lock);
774 /*** Per cpu kva allocator ***/
777 * vmap space is limited especially on 32 bit architectures. Ensure there is
778 * room for at least 16 percpu vmap blocks per CPU.
781 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
782 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
783 * instead (we just need a rough idea)
785 #if BITS_PER_LONG == 32
786 #define VMALLOC_SPACE (128UL*1024*1024)
788 #define VMALLOC_SPACE (128UL*1024*1024*1024)
791 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
792 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
793 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
794 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
795 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
796 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
797 #define VMAP_BBMAP_BITS \
798 VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
799 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
800 VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16))
802 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
804 static bool vmap_initialized __read_mostly = false;
806 struct vmap_block_queue {
808 struct list_head free;
813 struct vmap_area *va;
814 unsigned long free, dirty;
815 unsigned long dirty_min, dirty_max; /*< dirty range */
816 struct list_head free_list;
817 struct rcu_head rcu_head;
818 struct list_head purge;
821 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
822 static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
825 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
826 * in the free path. Could get rid of this if we change the API to return a
827 * "cookie" from alloc, to be passed to free. But no big deal yet.
829 static DEFINE_SPINLOCK(vmap_block_tree_lock);
830 static RADIX_TREE(vmap_block_tree, GFP_ATOMIC);
833 * We should probably have a fallback mechanism to allocate virtual memory
834 * out of partially filled vmap blocks. However vmap block sizing should be
835 * fairly reasonable according to the vmalloc size, so it shouldn't be a
839 static unsigned long addr_to_vb_idx(unsigned long addr)
841 addr -= VMALLOC_START & ~(VMAP_BLOCK_SIZE-1);
842 addr /= VMAP_BLOCK_SIZE;
846 static void *vmap_block_vaddr(unsigned long va_start, unsigned long pages_off)
850 addr = va_start + (pages_off << PAGE_SHIFT);
851 BUG_ON(addr_to_vb_idx(addr) != addr_to_vb_idx(va_start));
856 * new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
857 * block. Of course pages number can't exceed VMAP_BBMAP_BITS
858 * @order: how many 2^order pages should be occupied in newly allocated block
859 * @gfp_mask: flags for the page level allocator
861 * Returns: virtual address in a newly allocated block or ERR_PTR(-errno)
863 static void *new_vmap_block(unsigned int order, gfp_t gfp_mask)
865 struct vmap_block_queue *vbq;
866 struct vmap_block *vb;
867 struct vmap_area *va;
868 unsigned long vb_idx;
872 node = numa_node_id();
874 vb = kmalloc_node(sizeof(struct vmap_block),
875 gfp_mask & GFP_RECLAIM_MASK, node);
877 return ERR_PTR(-ENOMEM);
879 va = alloc_vmap_area(VMAP_BLOCK_SIZE, VMAP_BLOCK_SIZE,
880 VMALLOC_START, VMALLOC_END,
887 err = radix_tree_preload(gfp_mask);
894 vaddr = vmap_block_vaddr(va->va_start, 0);
895 spin_lock_init(&vb->lock);
897 /* At least something should be left free */
898 BUG_ON(VMAP_BBMAP_BITS <= (1UL << order));
899 vb->free = VMAP_BBMAP_BITS - (1UL << order);
901 vb->dirty_min = VMAP_BBMAP_BITS;
903 INIT_LIST_HEAD(&vb->free_list);
905 vb_idx = addr_to_vb_idx(va->va_start);
906 spin_lock(&vmap_block_tree_lock);
907 err = radix_tree_insert(&vmap_block_tree, vb_idx, vb);
908 spin_unlock(&vmap_block_tree_lock);
910 radix_tree_preload_end();
912 vbq = &get_cpu_var(vmap_block_queue);
913 spin_lock(&vbq->lock);
914 list_add_tail_rcu(&vb->free_list, &vbq->free);
915 spin_unlock(&vbq->lock);
916 put_cpu_var(vmap_block_queue);
921 static void free_vmap_block(struct vmap_block *vb)
923 struct vmap_block *tmp;
924 unsigned long vb_idx;
926 vb_idx = addr_to_vb_idx(vb->va->va_start);
927 spin_lock(&vmap_block_tree_lock);
928 tmp = radix_tree_delete(&vmap_block_tree, vb_idx);
929 spin_unlock(&vmap_block_tree_lock);
932 free_vmap_area_noflush(vb->va);
933 kfree_rcu(vb, rcu_head);
936 static void purge_fragmented_blocks(int cpu)
939 struct vmap_block *vb;
940 struct vmap_block *n_vb;
941 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
944 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
946 if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
949 spin_lock(&vb->lock);
950 if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
951 vb->free = 0; /* prevent further allocs after releasing lock */
952 vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
954 vb->dirty_max = VMAP_BBMAP_BITS;
955 spin_lock(&vbq->lock);
956 list_del_rcu(&vb->free_list);
957 spin_unlock(&vbq->lock);
958 spin_unlock(&vb->lock);
959 list_add_tail(&vb->purge, &purge);
961 spin_unlock(&vb->lock);
965 list_for_each_entry_safe(vb, n_vb, &purge, purge) {
966 list_del(&vb->purge);
971 static void purge_fragmented_blocks_allcpus(void)
975 for_each_possible_cpu(cpu)
976 purge_fragmented_blocks(cpu);
979 static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
981 struct vmap_block_queue *vbq;
982 struct vmap_block *vb;
986 BUG_ON(offset_in_page(size));
987 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
988 if (WARN_ON(size == 0)) {
990 * Allocating 0 bytes isn't what caller wants since
991 * get_order(0) returns funny result. Just warn and terminate
996 order = get_order(size);
999 vbq = &get_cpu_var(vmap_block_queue);
1000 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
1001 unsigned long pages_off;
1003 spin_lock(&vb->lock);
1004 if (vb->free < (1UL << order)) {
1005 spin_unlock(&vb->lock);
1009 pages_off = VMAP_BBMAP_BITS - vb->free;
1010 vaddr = vmap_block_vaddr(vb->va->va_start, pages_off);
1011 vb->free -= 1UL << order;
1012 if (vb->free == 0) {
1013 spin_lock(&vbq->lock);
1014 list_del_rcu(&vb->free_list);
1015 spin_unlock(&vbq->lock);
1018 spin_unlock(&vb->lock);
1022 put_cpu_var(vmap_block_queue);
1025 /* Allocate new block if nothing was found */
1027 vaddr = new_vmap_block(order, gfp_mask);
1032 static void vb_free(const void *addr, unsigned long size)
1034 unsigned long offset;
1035 unsigned long vb_idx;
1037 struct vmap_block *vb;
1039 BUG_ON(offset_in_page(size));
1040 BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
1042 flush_cache_vunmap((unsigned long)addr, (unsigned long)addr + size);
1044 order = get_order(size);
1046 offset = (unsigned long)addr & (VMAP_BLOCK_SIZE - 1);
1047 offset >>= PAGE_SHIFT;
1049 vb_idx = addr_to_vb_idx((unsigned long)addr);
1051 vb = radix_tree_lookup(&vmap_block_tree, vb_idx);
1055 vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
1057 spin_lock(&vb->lock);
1059 /* Expand dirty range */
1060 vb->dirty_min = min(vb->dirty_min, offset);
1061 vb->dirty_max = max(vb->dirty_max, offset + (1UL << order));
1063 vb->dirty += 1UL << order;
1064 if (vb->dirty == VMAP_BBMAP_BITS) {
1066 spin_unlock(&vb->lock);
1067 free_vmap_block(vb);
1069 spin_unlock(&vb->lock);
1073 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
1075 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
1076 * to amortize TLB flushing overheads. What this means is that any page you
1077 * have now, may, in a former life, have been mapped into kernel virtual
1078 * address by the vmap layer and so there might be some CPUs with TLB entries
1079 * still referencing that page (additional to the regular 1:1 kernel mapping).
1081 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
1082 * be sure that none of the pages we have control over will have any aliases
1083 * from the vmap layer.
1085 void vm_unmap_aliases(void)
1087 unsigned long start = ULONG_MAX, end = 0;
1091 if (unlikely(!vmap_initialized))
1096 for_each_possible_cpu(cpu) {
1097 struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
1098 struct vmap_block *vb;
1101 list_for_each_entry_rcu(vb, &vbq->free, free_list) {
1102 spin_lock(&vb->lock);
1104 unsigned long va_start = vb->va->va_start;
1107 s = va_start + (vb->dirty_min << PAGE_SHIFT);
1108 e = va_start + (vb->dirty_max << PAGE_SHIFT);
1110 start = min(s, start);
1115 spin_unlock(&vb->lock);
1120 mutex_lock(&vmap_purge_lock);
1121 purge_fragmented_blocks_allcpus();
1122 if (!__purge_vmap_area_lazy(start, end) && flush)
1123 flush_tlb_kernel_range(start, end);
1124 mutex_unlock(&vmap_purge_lock);
1126 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
1129 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1130 * @mem: the pointer returned by vm_map_ram
1131 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1133 void vm_unmap_ram(const void *mem, unsigned int count)
1135 unsigned long size = (unsigned long)count << PAGE_SHIFT;
1136 unsigned long addr = (unsigned long)mem;
1137 struct vmap_area *va;
1141 BUG_ON(addr < VMALLOC_START);
1142 BUG_ON(addr > VMALLOC_END);
1143 BUG_ON(!PAGE_ALIGNED(addr));
1145 debug_check_no_locks_freed(mem, size);
1146 vmap_debug_free_range(addr, addr+size);
1148 if (likely(count <= VMAP_MAX_ALLOC)) {
1153 va = find_vmap_area(addr);
1155 free_unmap_vmap_area(va);
1157 EXPORT_SYMBOL(vm_unmap_ram);
1160 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1161 * @pages: an array of pointers to the pages to be mapped
1162 * @count: number of pages
1163 * @node: prefer to allocate data structures on this node
1164 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
1166 * If you use this function for less than VMAP_MAX_ALLOC pages, it could be
1167 * faster than vmap so it's good. But if you mix long-life and short-life
1168 * objects with vm_map_ram(), it could consume lots of address space through
1169 * fragmentation (especially on a 32bit machine). You could see failures in
1170 * the end. Please use this function for short-lived objects.
1172 * Returns: a pointer to the address that has been mapped, or %NULL on failure
1174 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
1176 unsigned long size = (unsigned long)count << PAGE_SHIFT;
1180 if (likely(count <= VMAP_MAX_ALLOC)) {
1181 mem = vb_alloc(size, GFP_KERNEL);
1184 addr = (unsigned long)mem;
1186 struct vmap_area *va;
1187 va = alloc_vmap_area(size, PAGE_SIZE,
1188 VMALLOC_START, VMALLOC_END, node, GFP_KERNEL);
1192 addr = va->va_start;
1195 if (vmap_page_range(addr, addr + size, prot, pages) < 0) {
1196 vm_unmap_ram(mem, count);
1201 EXPORT_SYMBOL(vm_map_ram);
1203 static struct vm_struct *vmlist __initdata;
1205 * vm_area_add_early - add vmap area early during boot
1206 * @vm: vm_struct to add
1208 * This function is used to add fixed kernel vm area to vmlist before
1209 * vmalloc_init() is called. @vm->addr, @vm->size, and @vm->flags
1210 * should contain proper values and the other fields should be zero.
1212 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1214 void __init vm_area_add_early(struct vm_struct *vm)
1216 struct vm_struct *tmp, **p;
1218 BUG_ON(vmap_initialized);
1219 for (p = &vmlist; (tmp = *p) != NULL; p = &tmp->next) {
1220 if (tmp->addr >= vm->addr) {
1221 BUG_ON(tmp->addr < vm->addr + vm->size);
1224 BUG_ON(tmp->addr + tmp->size > vm->addr);
1231 * vm_area_register_early - register vmap area early during boot
1232 * @vm: vm_struct to register
1233 * @align: requested alignment
1235 * This function is used to register kernel vm area before
1236 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1237 * proper values on entry and other fields should be zero. On return,
1238 * vm->addr contains the allocated address.
1240 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1242 void __init vm_area_register_early(struct vm_struct *vm, size_t align)
1244 static size_t vm_init_off __initdata;
1247 addr = ALIGN(VMALLOC_START + vm_init_off, align);
1248 vm_init_off = PFN_ALIGN(addr + vm->size) - VMALLOC_START;
1250 vm->addr = (void *)addr;
1252 vm_area_add_early(vm);
1255 void __init vmalloc_init(void)
1257 struct vmap_area *va;
1258 struct vm_struct *tmp;
1261 for_each_possible_cpu(i) {
1262 struct vmap_block_queue *vbq;
1263 struct vfree_deferred *p;
1265 vbq = &per_cpu(vmap_block_queue, i);
1266 spin_lock_init(&vbq->lock);
1267 INIT_LIST_HEAD(&vbq->free);
1268 p = &per_cpu(vfree_deferred, i);
1269 init_llist_head(&p->list);
1270 INIT_WORK(&p->wq, free_work);
1273 /* Import existing vmlist entries. */
1274 for (tmp = vmlist; tmp; tmp = tmp->next) {
1275 va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT);
1276 va->flags = VM_VM_AREA;
1277 va->va_start = (unsigned long)tmp->addr;
1278 va->va_end = va->va_start + tmp->size;
1280 __insert_vmap_area(va);
1283 vmap_area_pcpu_hole = VMALLOC_END;
1285 vmap_initialized = true;
1289 * map_kernel_range_noflush - map kernel VM area with the specified pages
1290 * @addr: start of the VM area to map
1291 * @size: size of the VM area to map
1292 * @prot: page protection flags to use
1293 * @pages: pages to map
1295 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1296 * specify should have been allocated using get_vm_area() and its
1300 * This function does NOT do any cache flushing. The caller is
1301 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1302 * before calling this function.
1305 * The number of pages mapped on success, -errno on failure.
1307 int map_kernel_range_noflush(unsigned long addr, unsigned long size,
1308 pgprot_t prot, struct page **pages)
1310 return vmap_page_range_noflush(addr, addr + size, prot, pages);
1314 * unmap_kernel_range_noflush - unmap kernel VM area
1315 * @addr: start of the VM area to unmap
1316 * @size: size of the VM area to unmap
1318 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1319 * specify should have been allocated using get_vm_area() and its
1323 * This function does NOT do any cache flushing. The caller is
1324 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1325 * before calling this function and flush_tlb_kernel_range() after.
1327 void unmap_kernel_range_noflush(unsigned long addr, unsigned long size)
1329 vunmap_page_range(addr, addr + size);
1331 EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush);
1334 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1335 * @addr: start of the VM area to unmap
1336 * @size: size of the VM area to unmap
1338 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1339 * the unmapping and tlb after.
1341 void unmap_kernel_range(unsigned long addr, unsigned long size)
1343 unsigned long end = addr + size;
1345 flush_cache_vunmap(addr, end);
1346 vunmap_page_range(addr, end);
1347 flush_tlb_kernel_range(addr, end);
1349 EXPORT_SYMBOL_GPL(unmap_kernel_range);
1351 int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages)
1353 unsigned long addr = (unsigned long)area->addr;
1354 unsigned long end = addr + get_vm_area_size(area);
1357 err = vmap_page_range(addr, end, prot, pages);
1359 return err > 0 ? 0 : err;
1361 EXPORT_SYMBOL_GPL(map_vm_area);
1363 static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
1364 unsigned long flags, const void *caller)
1366 spin_lock(&vmap_area_lock);
1368 vm->addr = (void *)va->va_start;
1369 vm->size = va->va_end - va->va_start;
1370 vm->caller = caller;
1372 va->flags |= VM_VM_AREA;
1373 spin_unlock(&vmap_area_lock);
1376 static void clear_vm_uninitialized_flag(struct vm_struct *vm)
1379 * Before removing VM_UNINITIALIZED,
1380 * we should make sure that vm has proper values.
1381 * Pair with smp_rmb() in show_numa_info().
1384 vm->flags &= ~VM_UNINITIALIZED;
1387 static struct vm_struct *__get_vm_area_node(unsigned long size,
1388 unsigned long align, unsigned long flags, unsigned long start,
1389 unsigned long end, int node, gfp_t gfp_mask, const void *caller)
1391 struct vmap_area *va;
1392 struct vm_struct *area;
1394 BUG_ON(in_interrupt());
1395 size = PAGE_ALIGN(size);
1396 if (unlikely(!size))
1399 if (flags & VM_IOREMAP)
1400 align = 1ul << clamp_t(int, get_count_order_long(size),
1401 PAGE_SHIFT, IOREMAP_MAX_ORDER);
1403 area = kzalloc_node(sizeof(*area), gfp_mask & GFP_RECLAIM_MASK, node);
1404 if (unlikely(!area))
1407 if (!(flags & VM_NO_GUARD))
1410 va = alloc_vmap_area(size, align, start, end, node, gfp_mask);
1416 setup_vmalloc_vm(area, va, flags, caller);
1421 struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
1422 unsigned long start, unsigned long end)
1424 return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE,
1425 GFP_KERNEL, __builtin_return_address(0));
1427 EXPORT_SYMBOL_GPL(__get_vm_area);
1429 struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags,
1430 unsigned long start, unsigned long end,
1433 return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE,
1434 GFP_KERNEL, caller);
1438 * get_vm_area - reserve a contiguous kernel virtual area
1439 * @size: size of the area
1440 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
1442 * Search an area of @size in the kernel virtual mapping area,
1443 * and reserved it for out purposes. Returns the area descriptor
1444 * on success or %NULL on failure.
1446 struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
1448 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1449 NUMA_NO_NODE, GFP_KERNEL,
1450 __builtin_return_address(0));
1453 struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
1456 return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END,
1457 NUMA_NO_NODE, GFP_KERNEL, caller);
1461 * find_vm_area - find a continuous kernel virtual area
1462 * @addr: base address
1464 * Search for the kernel VM area starting at @addr, and return it.
1465 * It is up to the caller to do all required locking to keep the returned
1468 struct vm_struct *find_vm_area(const void *addr)
1470 struct vmap_area *va;
1472 va = find_vmap_area((unsigned long)addr);
1473 if (va && va->flags & VM_VM_AREA)
1480 * remove_vm_area - find and remove a continuous kernel virtual area
1481 * @addr: base address
1483 * Search for the kernel VM area starting at @addr, and remove it.
1484 * This function returns the found VM area, but using it is NOT safe
1485 * on SMP machines, except for its size or flags.
1487 struct vm_struct *remove_vm_area(const void *addr)
1489 struct vmap_area *va;
1493 va = find_vmap_area((unsigned long)addr);
1494 if (va && va->flags & VM_VM_AREA) {
1495 struct vm_struct *vm = va->vm;
1497 spin_lock(&vmap_area_lock);
1499 va->flags &= ~VM_VM_AREA;
1500 spin_unlock(&vmap_area_lock);
1502 vmap_debug_free_range(va->va_start, va->va_end);
1503 kasan_free_shadow(vm);
1504 free_unmap_vmap_area(va);
1511 static void __vunmap(const void *addr, int deallocate_pages)
1513 struct vm_struct *area;
1518 if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
1522 area = remove_vm_area(addr);
1523 if (unlikely(!area)) {
1524 WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
1529 debug_check_no_locks_freed(addr, get_vm_area_size(area));
1530 debug_check_no_obj_freed(addr, get_vm_area_size(area));
1532 if (deallocate_pages) {
1535 for (i = 0; i < area->nr_pages; i++) {
1536 struct page *page = area->pages[i];
1539 __free_pages(page, 0);
1542 kvfree(area->pages);
1549 static inline void __vfree_deferred(const void *addr)
1552 * Use raw_cpu_ptr() because this can be called from preemptible
1553 * context. Preemption is absolutely fine here, because the llist_add()
1554 * implementation is lockless, so it works even if we are adding to
1555 * nother cpu's list. schedule_work() should be fine with this too.
1557 struct vfree_deferred *p = raw_cpu_ptr(&vfree_deferred);
1559 if (llist_add((struct llist_node *)addr, &p->list))
1560 schedule_work(&p->wq);
1564 * vfree_atomic - release memory allocated by vmalloc()
1565 * @addr: memory base address
1567 * This one is just like vfree() but can be called in any atomic context
1570 void vfree_atomic(const void *addr)
1574 kmemleak_free(addr);
1578 __vfree_deferred(addr);
1582 * vfree - release memory allocated by vmalloc()
1583 * @addr: memory base address
1585 * Free the virtually continuous memory area starting at @addr, as
1586 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
1587 * NULL, no operation is performed.
1589 * Must not be called in NMI context (strictly speaking, only if we don't
1590 * have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
1591 * conventions for vfree() arch-depenedent would be a really bad idea)
1593 * NOTE: assumes that the object at @addr has a size >= sizeof(llist_node)
1595 void vfree(const void *addr)
1599 kmemleak_free(addr);
1603 if (unlikely(in_interrupt()))
1604 __vfree_deferred(addr);
1608 EXPORT_SYMBOL(vfree);
1611 * vunmap - release virtual mapping obtained by vmap()
1612 * @addr: memory base address
1614 * Free the virtually contiguous memory area starting at @addr,
1615 * which was created from the page array passed to vmap().
1617 * Must not be called in interrupt context.
1619 void vunmap(const void *addr)
1621 BUG_ON(in_interrupt());
1626 EXPORT_SYMBOL(vunmap);
1629 * vmap - map an array of pages into virtually contiguous space
1630 * @pages: array of page pointers
1631 * @count: number of pages to map
1632 * @flags: vm_area->flags
1633 * @prot: page protection for the mapping
1635 * Maps @count pages from @pages into contiguous kernel virtual
1638 void *vmap(struct page **pages, unsigned int count,
1639 unsigned long flags, pgprot_t prot)
1641 struct vm_struct *area;
1642 unsigned long size; /* In bytes */
1646 if (count > totalram_pages)
1649 size = (unsigned long)count << PAGE_SHIFT;
1650 area = get_vm_area_caller(size, flags, __builtin_return_address(0));
1654 if (map_vm_area(area, prot, pages)) {
1661 EXPORT_SYMBOL(vmap);
1663 static void *__vmalloc_node(unsigned long size, unsigned long align,
1664 gfp_t gfp_mask, pgprot_t prot,
1665 int node, const void *caller);
1666 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
1667 pgprot_t prot, int node)
1669 struct page **pages;
1670 unsigned int nr_pages, array_size, i;
1671 const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
1672 const gfp_t alloc_mask = gfp_mask | __GFP_HIGHMEM | __GFP_NOWARN;
1674 nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
1675 array_size = (nr_pages * sizeof(struct page *));
1677 area->nr_pages = nr_pages;
1678 /* Please note that the recursion is strictly bounded. */
1679 if (array_size > PAGE_SIZE) {
1680 pages = __vmalloc_node(array_size, 1, nested_gfp|__GFP_HIGHMEM,
1681 PAGE_KERNEL, node, area->caller);
1683 pages = kmalloc_node(array_size, nested_gfp, node);
1685 area->pages = pages;
1687 remove_vm_area(area->addr);
1692 for (i = 0; i < area->nr_pages; i++) {
1695 if (fatal_signal_pending(current)) {
1700 if (node == NUMA_NO_NODE)
1701 page = alloc_page(alloc_mask);
1703 page = alloc_pages_node(node, alloc_mask, 0);
1705 if (unlikely(!page)) {
1706 /* Successfully allocated i pages, free them in __vunmap() */
1710 area->pages[i] = page;
1711 if (gfpflags_allow_blocking(gfp_mask))
1715 if (map_vm_area(area, prot, pages))
1720 warn_alloc(gfp_mask, NULL,
1721 "vmalloc: allocation failure, allocated %ld of %ld bytes",
1722 (area->nr_pages*PAGE_SIZE), area->size);
1729 * __vmalloc_node_range - allocate virtually contiguous memory
1730 * @size: allocation size
1731 * @align: desired alignment
1732 * @start: vm area range start
1733 * @end: vm area range end
1734 * @gfp_mask: flags for the page level allocator
1735 * @prot: protection mask for the allocated pages
1736 * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD)
1737 * @node: node to use for allocation or NUMA_NO_NODE
1738 * @caller: caller's return address
1740 * Allocate enough pages to cover @size from the page level
1741 * allocator with @gfp_mask flags. Map them into contiguous
1742 * kernel virtual space, using a pagetable protection of @prot.
1744 void *__vmalloc_node_range(unsigned long size, unsigned long align,
1745 unsigned long start, unsigned long end, gfp_t gfp_mask,
1746 pgprot_t prot, unsigned long vm_flags, int node,
1749 struct vm_struct *area;
1751 unsigned long real_size = size;
1753 size = PAGE_ALIGN(size);
1754 if (!size || (size >> PAGE_SHIFT) > totalram_pages)
1757 area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED |
1758 vm_flags, start, end, node, gfp_mask, caller);
1762 addr = __vmalloc_area_node(area, gfp_mask, prot, node);
1767 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
1768 * flag. It means that vm_struct is not fully initialized.
1769 * Now, it is fully initialized, so remove this flag here.
1771 clear_vm_uninitialized_flag(area);
1773 kmemleak_vmalloc(area, size, gfp_mask);
1778 warn_alloc(gfp_mask, NULL,
1779 "vmalloc: allocation failure: %lu bytes", real_size);
1784 * __vmalloc_node - allocate virtually contiguous memory
1785 * @size: allocation size
1786 * @align: desired alignment
1787 * @gfp_mask: flags for the page level allocator
1788 * @prot: protection mask for the allocated pages
1789 * @node: node to use for allocation or NUMA_NO_NODE
1790 * @caller: caller's return address
1792 * Allocate enough pages to cover @size from the page level
1793 * allocator with @gfp_mask flags. Map them into contiguous
1794 * kernel virtual space, using a pagetable protection of @prot.
1796 * Reclaim modifiers in @gfp_mask - __GFP_NORETRY, __GFP_REPEAT
1797 * and __GFP_NOFAIL are not supported
1799 * Any use of gfp flags outside of GFP_KERNEL should be consulted
1803 static void *__vmalloc_node(unsigned long size, unsigned long align,
1804 gfp_t gfp_mask, pgprot_t prot,
1805 int node, const void *caller)
1807 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
1808 gfp_mask, prot, 0, node, caller);
1811 void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
1813 return __vmalloc_node(size, 1, gfp_mask, prot, NUMA_NO_NODE,
1814 __builtin_return_address(0));
1816 EXPORT_SYMBOL(__vmalloc);
1818 static inline void *__vmalloc_node_flags(unsigned long size,
1819 int node, gfp_t flags)
1821 return __vmalloc_node(size, 1, flags, PAGE_KERNEL,
1822 node, __builtin_return_address(0));
1826 void *__vmalloc_node_flags_caller(unsigned long size, int node, gfp_t flags,
1829 return __vmalloc_node(size, 1, flags, PAGE_KERNEL, node, caller);
1833 * vmalloc - allocate virtually contiguous memory
1834 * @size: allocation size
1835 * Allocate enough pages to cover @size from the page level
1836 * allocator and map them into contiguous kernel virtual space.
1838 * For tight control over page level allocator and protection flags
1839 * use __vmalloc() instead.
1841 void *vmalloc(unsigned long size)
1843 return __vmalloc_node_flags(size, NUMA_NO_NODE,
1846 EXPORT_SYMBOL(vmalloc);
1849 * vzalloc - allocate virtually contiguous memory with zero fill
1850 * @size: allocation size
1851 * Allocate enough pages to cover @size from the page level
1852 * allocator and map them into contiguous kernel virtual space.
1853 * The memory allocated is set to zero.
1855 * For tight control over page level allocator and protection flags
1856 * use __vmalloc() instead.
1858 void *vzalloc(unsigned long size)
1860 return __vmalloc_node_flags(size, NUMA_NO_NODE,
1861 GFP_KERNEL | __GFP_ZERO);
1863 EXPORT_SYMBOL(vzalloc);
1866 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
1867 * @size: allocation size
1869 * The resulting memory area is zeroed so it can be mapped to userspace
1870 * without leaking data.
1872 void *vmalloc_user(unsigned long size)
1874 struct vm_struct *area;
1877 ret = __vmalloc_node(size, SHMLBA,
1878 GFP_KERNEL | __GFP_ZERO,
1879 PAGE_KERNEL, NUMA_NO_NODE,
1880 __builtin_return_address(0));
1882 area = find_vm_area(ret);
1883 area->flags |= VM_USERMAP;
1887 EXPORT_SYMBOL(vmalloc_user);
1890 * vmalloc_node - allocate memory on a specific node
1891 * @size: allocation size
1894 * Allocate enough pages to cover @size from the page level
1895 * allocator and map them into contiguous kernel virtual space.
1897 * For tight control over page level allocator and protection flags
1898 * use __vmalloc() instead.
1900 void *vmalloc_node(unsigned long size, int node)
1902 return __vmalloc_node(size, 1, GFP_KERNEL, PAGE_KERNEL,
1903 node, __builtin_return_address(0));
1905 EXPORT_SYMBOL(vmalloc_node);
1908 * vzalloc_node - allocate memory on a specific node with zero fill
1909 * @size: allocation size
1912 * Allocate enough pages to cover @size from the page level
1913 * allocator and map them into contiguous kernel virtual space.
1914 * The memory allocated is set to zero.
1916 * For tight control over page level allocator and protection flags
1917 * use __vmalloc_node() instead.
1919 void *vzalloc_node(unsigned long size, int node)
1921 return __vmalloc_node_flags(size, node,
1922 GFP_KERNEL | __GFP_ZERO);
1924 EXPORT_SYMBOL(vzalloc_node);
1926 #ifndef PAGE_KERNEL_EXEC
1927 # define PAGE_KERNEL_EXEC PAGE_KERNEL
1931 * vmalloc_exec - allocate virtually contiguous, executable memory
1932 * @size: allocation size
1934 * Kernel-internal function to allocate enough pages to cover @size
1935 * the page level allocator and map them into contiguous and
1936 * executable kernel virtual space.
1938 * For tight control over page level allocator and protection flags
1939 * use __vmalloc() instead.
1942 void *vmalloc_exec(unsigned long size)
1944 return __vmalloc_node(size, 1, GFP_KERNEL, PAGE_KERNEL_EXEC,
1945 NUMA_NO_NODE, __builtin_return_address(0));
1948 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
1949 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
1950 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
1951 #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
1953 #define GFP_VMALLOC32 GFP_KERNEL
1957 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
1958 * @size: allocation size
1960 * Allocate enough 32bit PA addressable pages to cover @size from the
1961 * page level allocator and map them into contiguous kernel virtual space.
1963 void *vmalloc_32(unsigned long size)
1965 return __vmalloc_node(size, 1, GFP_VMALLOC32, PAGE_KERNEL,
1966 NUMA_NO_NODE, __builtin_return_address(0));
1968 EXPORT_SYMBOL(vmalloc_32);
1971 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
1972 * @size: allocation size
1974 * The resulting memory area is 32bit addressable and zeroed so it can be
1975 * mapped to userspace without leaking data.
1977 void *vmalloc_32_user(unsigned long size)
1979 struct vm_struct *area;
1982 ret = __vmalloc_node(size, 1, GFP_VMALLOC32 | __GFP_ZERO, PAGE_KERNEL,
1983 NUMA_NO_NODE, __builtin_return_address(0));
1985 area = find_vm_area(ret);
1986 area->flags |= VM_USERMAP;
1990 EXPORT_SYMBOL(vmalloc_32_user);
1993 * small helper routine , copy contents to buf from addr.
1994 * If the page is not present, fill zero.
1997 static int aligned_vread(char *buf, char *addr, unsigned long count)
2003 unsigned long offset, length;
2005 offset = offset_in_page(addr);
2006 length = PAGE_SIZE - offset;
2009 p = vmalloc_to_page(addr);
2011 * To do safe access to this _mapped_ area, we need
2012 * lock. But adding lock here means that we need to add
2013 * overhead of vmalloc()/vfree() calles for this _debug_
2014 * interface, rarely used. Instead of that, we'll use
2015 * kmap() and get small overhead in this access function.
2019 * we can expect USER0 is not used (see vread/vwrite's
2020 * function description)
2022 void *map = kmap_atomic(p);
2023 memcpy(buf, map + offset, length);
2026 memset(buf, 0, length);
2036 static int aligned_vwrite(char *buf, char *addr, unsigned long count)
2042 unsigned long offset, length;
2044 offset = offset_in_page(addr);
2045 length = PAGE_SIZE - offset;
2048 p = vmalloc_to_page(addr);
2050 * To do safe access to this _mapped_ area, we need
2051 * lock. But adding lock here means that we need to add
2052 * overhead of vmalloc()/vfree() calles for this _debug_
2053 * interface, rarely used. Instead of that, we'll use
2054 * kmap() and get small overhead in this access function.
2058 * we can expect USER0 is not used (see vread/vwrite's
2059 * function description)
2061 void *map = kmap_atomic(p);
2062 memcpy(map + offset, buf, length);
2074 * vread() - read vmalloc area in a safe way.
2075 * @buf: buffer for reading data
2076 * @addr: vm address.
2077 * @count: number of bytes to be read.
2079 * Returns # of bytes which addr and buf should be increased.
2080 * (same number to @count). Returns 0 if [addr...addr+count) doesn't
2081 * includes any intersect with alive vmalloc area.
2083 * This function checks that addr is a valid vmalloc'ed area, and
2084 * copy data from that area to a given buffer. If the given memory range
2085 * of [addr...addr+count) includes some valid address, data is copied to
2086 * proper area of @buf. If there are memory holes, they'll be zero-filled.
2087 * IOREMAP area is treated as memory hole and no copy is done.
2089 * If [addr...addr+count) doesn't includes any intersects with alive
2090 * vm_struct area, returns 0. @buf should be kernel's buffer.
2092 * Note: In usual ops, vread() is never necessary because the caller
2093 * should know vmalloc() area is valid and can use memcpy().
2094 * This is for routines which have to access vmalloc area without
2095 * any informaion, as /dev/kmem.
2099 long vread(char *buf, char *addr, unsigned long count)
2101 struct vmap_area *va;
2102 struct vm_struct *vm;
2103 char *vaddr, *buf_start = buf;
2104 unsigned long buflen = count;
2107 /* Don't allow overflow */
2108 if ((unsigned long) addr + count < count)
2109 count = -(unsigned long) addr;
2111 spin_lock(&vmap_area_lock);
2112 list_for_each_entry(va, &vmap_area_list, list) {
2116 if (!(va->flags & VM_VM_AREA))
2120 vaddr = (char *) vm->addr;
2121 if (addr >= vaddr + get_vm_area_size(vm))
2123 while (addr < vaddr) {
2131 n = vaddr + get_vm_area_size(vm) - addr;
2134 if (!(vm->flags & VM_IOREMAP))
2135 aligned_vread(buf, addr, n);
2136 else /* IOREMAP area is treated as memory hole */
2143 spin_unlock(&vmap_area_lock);
2145 if (buf == buf_start)
2147 /* zero-fill memory holes */
2148 if (buf != buf_start + buflen)
2149 memset(buf, 0, buflen - (buf - buf_start));
2155 * vwrite() - write vmalloc area in a safe way.
2156 * @buf: buffer for source data
2157 * @addr: vm address.
2158 * @count: number of bytes to be read.
2160 * Returns # of bytes which addr and buf should be incresed.
2161 * (same number to @count).
2162 * If [addr...addr+count) doesn't includes any intersect with valid
2163 * vmalloc area, returns 0.
2165 * This function checks that addr is a valid vmalloc'ed area, and
2166 * copy data from a buffer to the given addr. If specified range of
2167 * [addr...addr+count) includes some valid address, data is copied from
2168 * proper area of @buf. If there are memory holes, no copy to hole.
2169 * IOREMAP area is treated as memory hole and no copy is done.
2171 * If [addr...addr+count) doesn't includes any intersects with alive
2172 * vm_struct area, returns 0. @buf should be kernel's buffer.
2174 * Note: In usual ops, vwrite() is never necessary because the caller
2175 * should know vmalloc() area is valid and can use memcpy().
2176 * This is for routines which have to access vmalloc area without
2177 * any informaion, as /dev/kmem.
2180 long vwrite(char *buf, char *addr, unsigned long count)
2182 struct vmap_area *va;
2183 struct vm_struct *vm;
2185 unsigned long n, buflen;
2188 /* Don't allow overflow */
2189 if ((unsigned long) addr + count < count)
2190 count = -(unsigned long) addr;
2193 spin_lock(&vmap_area_lock);
2194 list_for_each_entry(va, &vmap_area_list, list) {
2198 if (!(va->flags & VM_VM_AREA))
2202 vaddr = (char *) vm->addr;
2203 if (addr >= vaddr + get_vm_area_size(vm))
2205 while (addr < vaddr) {
2212 n = vaddr + get_vm_area_size(vm) - addr;
2215 if (!(vm->flags & VM_IOREMAP)) {
2216 aligned_vwrite(buf, addr, n);
2224 spin_unlock(&vmap_area_lock);
2231 * remap_vmalloc_range_partial - map vmalloc pages to userspace
2232 * @vma: vma to cover
2233 * @uaddr: target user address to start at
2234 * @kaddr: virtual address of vmalloc kernel memory
2235 * @size: size of map area
2237 * Returns: 0 for success, -Exxx on failure
2239 * This function checks that @kaddr is a valid vmalloc'ed area,
2240 * and that it is big enough to cover the range starting at
2241 * @uaddr in @vma. Will return failure if that criteria isn't
2244 * Similar to remap_pfn_range() (see mm/memory.c)
2246 int remap_vmalloc_range_partial(struct vm_area_struct *vma, unsigned long uaddr,
2247 void *kaddr, unsigned long size)
2249 struct vm_struct *area;
2251 size = PAGE_ALIGN(size);
2253 if (!PAGE_ALIGNED(uaddr) || !PAGE_ALIGNED(kaddr))
2256 area = find_vm_area(kaddr);
2260 if (!(area->flags & VM_USERMAP))
2263 if (kaddr + size > area->addr + area->size)
2267 struct page *page = vmalloc_to_page(kaddr);
2270 ret = vm_insert_page(vma, uaddr, page);
2279 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
2283 EXPORT_SYMBOL(remap_vmalloc_range_partial);
2286 * remap_vmalloc_range - map vmalloc pages to userspace
2287 * @vma: vma to cover (map full range of vma)
2288 * @addr: vmalloc memory
2289 * @pgoff: number of pages into addr before first page to map
2291 * Returns: 0 for success, -Exxx on failure
2293 * This function checks that addr is a valid vmalloc'ed area, and
2294 * that it is big enough to cover the vma. Will return failure if
2295 * that criteria isn't met.
2297 * Similar to remap_pfn_range() (see mm/memory.c)
2299 int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
2300 unsigned long pgoff)
2302 return remap_vmalloc_range_partial(vma, vma->vm_start,
2303 addr + (pgoff << PAGE_SHIFT),
2304 vma->vm_end - vma->vm_start);
2306 EXPORT_SYMBOL(remap_vmalloc_range);
2309 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
2312 void __weak vmalloc_sync_all(void)
2317 static int f(pte_t *pte, pgtable_t table, unsigned long addr, void *data)
2329 * alloc_vm_area - allocate a range of kernel address space
2330 * @size: size of the area
2331 * @ptes: returns the PTEs for the address space
2333 * Returns: NULL on failure, vm_struct on success
2335 * This function reserves a range of kernel address space, and
2336 * allocates pagetables to map that range. No actual mappings
2339 * If @ptes is non-NULL, pointers to the PTEs (in init_mm)
2340 * allocated for the VM area are returned.
2342 struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
2344 struct vm_struct *area;
2346 area = get_vm_area_caller(size, VM_IOREMAP,
2347 __builtin_return_address(0));
2352 * This ensures that page tables are constructed for this region
2353 * of kernel virtual address space and mapped into init_mm.
2355 if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
2356 size, f, ptes ? &ptes : NULL)) {
2363 EXPORT_SYMBOL_GPL(alloc_vm_area);
2365 void free_vm_area(struct vm_struct *area)
2367 struct vm_struct *ret;
2368 ret = remove_vm_area(area->addr);
2369 BUG_ON(ret != area);
2372 EXPORT_SYMBOL_GPL(free_vm_area);
2375 static struct vmap_area *node_to_va(struct rb_node *n)
2377 return rb_entry_safe(n, struct vmap_area, rb_node);
2381 * pvm_find_next_prev - find the next and prev vmap_area surrounding @end
2382 * @end: target address
2383 * @pnext: out arg for the next vmap_area
2384 * @pprev: out arg for the previous vmap_area
2386 * Returns: %true if either or both of next and prev are found,
2387 * %false if no vmap_area exists
2389 * Find vmap_areas end addresses of which enclose @end. ie. if not
2390 * NULL, *pnext->va_end > @end and *pprev->va_end <= @end.
2392 static bool pvm_find_next_prev(unsigned long end,
2393 struct vmap_area **pnext,
2394 struct vmap_area **pprev)
2396 struct rb_node *n = vmap_area_root.rb_node;
2397 struct vmap_area *va = NULL;
2400 va = rb_entry(n, struct vmap_area, rb_node);
2401 if (end < va->va_end)
2403 else if (end > va->va_end)
2412 if (va->va_end > end) {
2414 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2417 *pnext = node_to_va(rb_next(&(*pprev)->rb_node));
2423 * pvm_determine_end - find the highest aligned address between two vmap_areas
2424 * @pnext: in/out arg for the next vmap_area
2425 * @pprev: in/out arg for the previous vmap_area
2428 * Returns: determined end address
2430 * Find the highest aligned address between *@pnext and *@pprev below
2431 * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned
2432 * down address is between the end addresses of the two vmap_areas.
2434 * Please note that the address returned by this function may fall
2435 * inside *@pnext vmap_area. The caller is responsible for checking
2438 static unsigned long pvm_determine_end(struct vmap_area **pnext,
2439 struct vmap_area **pprev,
2440 unsigned long align)
2442 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2446 addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end);
2450 while (*pprev && (*pprev)->va_end > addr) {
2452 *pprev = node_to_va(rb_prev(&(*pnext)->rb_node));
2459 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
2460 * @offsets: array containing offset of each area
2461 * @sizes: array containing size of each area
2462 * @nr_vms: the number of areas to allocate
2463 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
2465 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
2466 * vm_structs on success, %NULL on failure
2468 * Percpu allocator wants to use congruent vm areas so that it can
2469 * maintain the offsets among percpu areas. This function allocates
2470 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
2471 * be scattered pretty far, distance between two areas easily going up
2472 * to gigabytes. To avoid interacting with regular vmallocs, these
2473 * areas are allocated from top.
2475 * Despite its complicated look, this allocator is rather simple. It
2476 * does everything top-down and scans areas from the end looking for
2477 * matching slot. While scanning, if any of the areas overlaps with
2478 * existing vmap_area, the base address is pulled down to fit the
2479 * area. Scanning is repeated till all the areas fit and then all
2480 * necessary data structres are inserted and the result is returned.
2482 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
2483 const size_t *sizes, int nr_vms,
2486 const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align);
2487 const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1);
2488 struct vmap_area **vas, *prev, *next;
2489 struct vm_struct **vms;
2490 int area, area2, last_area, term_area;
2491 unsigned long base, start, end, last_end;
2492 bool purged = false;
2494 /* verify parameters and allocate data structures */
2495 BUG_ON(offset_in_page(align) || !is_power_of_2(align));
2496 for (last_area = 0, area = 0; area < nr_vms; area++) {
2497 start = offsets[area];
2498 end = start + sizes[area];
2500 /* is everything aligned properly? */
2501 BUG_ON(!IS_ALIGNED(offsets[area], align));
2502 BUG_ON(!IS_ALIGNED(sizes[area], align));
2504 /* detect the area with the highest address */
2505 if (start > offsets[last_area])
2508 for (area2 = 0; area2 < nr_vms; area2++) {
2509 unsigned long start2 = offsets[area2];
2510 unsigned long end2 = start2 + sizes[area2];
2515 BUG_ON(start2 >= start && start2 < end);
2516 BUG_ON(end2 <= end && end2 > start);
2519 last_end = offsets[last_area] + sizes[last_area];
2521 if (vmalloc_end - vmalloc_start < last_end) {
2526 vms = kcalloc(nr_vms, sizeof(vms[0]), GFP_KERNEL);
2527 vas = kcalloc(nr_vms, sizeof(vas[0]), GFP_KERNEL);
2531 for (area = 0; area < nr_vms; area++) {
2532 vas[area] = kzalloc(sizeof(struct vmap_area), GFP_KERNEL);
2533 vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL);
2534 if (!vas[area] || !vms[area])
2538 spin_lock(&vmap_area_lock);
2540 /* start scanning - we scan from the top, begin with the last area */
2541 area = term_area = last_area;
2542 start = offsets[area];
2543 end = start + sizes[area];
2545 if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) {
2546 base = vmalloc_end - last_end;
2549 base = pvm_determine_end(&next, &prev, align) - end;
2552 BUG_ON(next && next->va_end <= base + end);
2553 BUG_ON(prev && prev->va_end > base + end);
2556 * base might have underflowed, add last_end before
2559 if (base + last_end < vmalloc_start + last_end) {
2560 spin_unlock(&vmap_area_lock);
2562 purge_vmap_area_lazy();
2570 * If next overlaps, move base downwards so that it's
2571 * right below next and then recheck.
2573 if (next && next->va_start < base + end) {
2574 base = pvm_determine_end(&next, &prev, align) - end;
2580 * If prev overlaps, shift down next and prev and move
2581 * base so that it's right below new next and then
2584 if (prev && prev->va_end > base + start) {
2586 prev = node_to_va(rb_prev(&next->rb_node));
2587 base = pvm_determine_end(&next, &prev, align) - end;
2593 * This area fits, move on to the previous one. If
2594 * the previous one is the terminal one, we're done.
2596 area = (area + nr_vms - 1) % nr_vms;
2597 if (area == term_area)
2599 start = offsets[area];
2600 end = start + sizes[area];
2601 pvm_find_next_prev(base + end, &next, &prev);
2604 /* we've found a fitting base, insert all va's */
2605 for (area = 0; area < nr_vms; area++) {
2606 struct vmap_area *va = vas[area];
2608 va->va_start = base + offsets[area];
2609 va->va_end = va->va_start + sizes[area];
2610 __insert_vmap_area(va);
2613 vmap_area_pcpu_hole = base + offsets[last_area];
2615 spin_unlock(&vmap_area_lock);
2617 /* insert all vm's */
2618 for (area = 0; area < nr_vms; area++)
2619 setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
2626 for (area = 0; area < nr_vms; area++) {
2637 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
2638 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
2639 * @nr_vms: the number of allocated areas
2641 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
2643 void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
2647 for (i = 0; i < nr_vms; i++)
2648 free_vm_area(vms[i]);
2651 #endif /* CONFIG_SMP */
2653 #ifdef CONFIG_PROC_FS
2654 static void *s_start(struct seq_file *m, loff_t *pos)
2655 __acquires(&vmap_area_lock)
2657 spin_lock(&vmap_area_lock);
2658 return seq_list_start(&vmap_area_list, *pos);
2661 static void *s_next(struct seq_file *m, void *p, loff_t *pos)
2663 return seq_list_next(p, &vmap_area_list, pos);
2666 static void s_stop(struct seq_file *m, void *p)
2667 __releases(&vmap_area_lock)
2669 spin_unlock(&vmap_area_lock);
2672 static void show_numa_info(struct seq_file *m, struct vm_struct *v)
2674 if (IS_ENABLED(CONFIG_NUMA)) {
2675 unsigned int nr, *counters = m->private;
2680 if (v->flags & VM_UNINITIALIZED)
2682 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
2685 memset(counters, 0, nr_node_ids * sizeof(unsigned int));
2687 for (nr = 0; nr < v->nr_pages; nr++)
2688 counters[page_to_nid(v->pages[nr])]++;
2690 for_each_node_state(nr, N_HIGH_MEMORY)
2692 seq_printf(m, " N%u=%u", nr, counters[nr]);
2696 static int s_show(struct seq_file *m, void *p)
2698 struct vmap_area *va;
2699 struct vm_struct *v;
2701 va = list_entry(p, struct vmap_area, list);
2704 * s_show can encounter race with remove_vm_area, !VM_VM_AREA on
2705 * behalf of vmap area is being tear down or vm_map_ram allocation.
2707 if (!(va->flags & VM_VM_AREA))
2712 seq_printf(m, "0x%pK-0x%pK %7ld",
2713 v->addr, v->addr + v->size, v->size);
2716 seq_printf(m, " %pS", v->caller);
2719 seq_printf(m, " pages=%d", v->nr_pages);
2722 seq_printf(m, " phys=%pa", &v->phys_addr);
2724 if (v->flags & VM_IOREMAP)
2725 seq_puts(m, " ioremap");
2727 if (v->flags & VM_ALLOC)
2728 seq_puts(m, " vmalloc");
2730 if (v->flags & VM_MAP)
2731 seq_puts(m, " vmap");
2733 if (v->flags & VM_USERMAP)
2734 seq_puts(m, " user");
2736 if (is_vmalloc_addr(v->pages))
2737 seq_puts(m, " vpages");
2739 show_numa_info(m, v);
2744 static const struct seq_operations vmalloc_op = {
2751 static int vmalloc_open(struct inode *inode, struct file *file)
2753 if (IS_ENABLED(CONFIG_NUMA))
2754 return seq_open_private(file, &vmalloc_op,
2755 nr_node_ids * sizeof(unsigned int));
2757 return seq_open(file, &vmalloc_op);
2760 static const struct file_operations proc_vmalloc_operations = {
2761 .open = vmalloc_open,
2763 .llseek = seq_lseek,
2764 .release = seq_release_private,
2767 static int __init proc_vmalloc_init(void)
2769 proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
2772 module_init(proc_vmalloc_init);