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/set_memory.h>
22 #include <linux/debugobjects.h>
23 #include <linux/kallsyms.h>
24 #include <linux/list.h>
25 #include <linux/notifier.h>
26 #include <linux/rbtree.h>
27 #include <linux/radix-tree.h>
28 #include <linux/rcupdate.h>
29 #include <linux/pfn.h>
30 #include <linux/kmemleak.h>
31 #include <linux/atomic.h>
32 #include <linux/compiler.h>
33 #include <linux/llist.h>
34 #include <linux/bitops.h>
35 #include <linux/rbtree_augmented.h>
37 #include <linux/uaccess.h>
38 #include <asm/tlbflush.h>
39 #include <asm/shmparam.h>
43 struct vfree_deferred
{
44 struct llist_head list
;
45 struct work_struct wq
;
47 static DEFINE_PER_CPU(struct vfree_deferred
, vfree_deferred
);
49 static void __vunmap(const void *, int);
51 static void free_work(struct work_struct
*w
)
53 struct vfree_deferred
*p
= container_of(w
, struct vfree_deferred
, wq
);
54 struct llist_node
*t
, *llnode
;
56 llist_for_each_safe(llnode
, t
, llist_del_all(&p
->list
))
57 __vunmap((void *)llnode
, 1);
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 DEBUG_AUGMENT_PROPAGATE_CHECK 0
329 #define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
331 #define VM_LAZY_FREE 0x02
332 #define VM_VM_AREA 0x04
334 static DEFINE_SPINLOCK(vmap_area_lock
);
335 /* Export for kexec only */
336 LIST_HEAD(vmap_area_list
);
337 static LLIST_HEAD(vmap_purge_list
);
338 static struct rb_root vmap_area_root
= RB_ROOT
;
339 static bool vmap_initialized __read_mostly
;
342 * This kmem_cache is used for vmap_area objects. Instead of
343 * allocating from slab we reuse an object from this cache to
344 * make things faster. Especially in "no edge" splitting of
347 static struct kmem_cache
*vmap_area_cachep
;
350 * This linked list is used in pair with free_vmap_area_root.
351 * It gives O(1) access to prev/next to perform fast coalescing.
353 static LIST_HEAD(free_vmap_area_list
);
356 * This augment red-black tree represents the free vmap space.
357 * All vmap_area objects in this tree are sorted by va->va_start
358 * address. It is used for allocation and merging when a vmap
359 * object is released.
361 * Each vmap_area node contains a maximum available free block
362 * of its sub-tree, right or left. Therefore it is possible to
363 * find a lowest match of free area.
365 static struct rb_root free_vmap_area_root
= RB_ROOT
;
367 static __always_inline
unsigned long
368 va_size(struct vmap_area
*va
)
370 return (va
->va_end
- va
->va_start
);
373 static __always_inline
unsigned long
374 get_subtree_max_size(struct rb_node
*node
)
376 struct vmap_area
*va
;
378 va
= rb_entry_safe(node
, struct vmap_area
, rb_node
);
379 return va
? va
->subtree_max_size
: 0;
383 * Gets called when remove the node and rotate.
385 static __always_inline
unsigned long
386 compute_subtree_max_size(struct vmap_area
*va
)
388 return max3(va_size(va
),
389 get_subtree_max_size(va
->rb_node
.rb_left
),
390 get_subtree_max_size(va
->rb_node
.rb_right
));
393 RB_DECLARE_CALLBACKS(static, free_vmap_area_rb_augment_cb
,
394 struct vmap_area
, rb_node
, unsigned long, subtree_max_size
,
395 compute_subtree_max_size
)
397 static void purge_vmap_area_lazy(void);
398 static BLOCKING_NOTIFIER_HEAD(vmap_notify_list
);
399 static unsigned long lazy_max_pages(void);
401 static struct vmap_area
*__find_vmap_area(unsigned long addr
)
403 struct rb_node
*n
= vmap_area_root
.rb_node
;
406 struct vmap_area
*va
;
408 va
= rb_entry(n
, struct vmap_area
, rb_node
);
409 if (addr
< va
->va_start
)
411 else if (addr
>= va
->va_end
)
421 * This function returns back addresses of parent node
422 * and its left or right link for further processing.
424 static __always_inline
struct rb_node
**
425 find_va_links(struct vmap_area
*va
,
426 struct rb_root
*root
, struct rb_node
*from
,
427 struct rb_node
**parent
)
429 struct vmap_area
*tmp_va
;
430 struct rb_node
**link
;
433 link
= &root
->rb_node
;
434 if (unlikely(!*link
)) {
443 * Go to the bottom of the tree. When we hit the last point
444 * we end up with parent rb_node and correct direction, i name
445 * it link, where the new va->rb_node will be attached to.
448 tmp_va
= rb_entry(*link
, struct vmap_area
, rb_node
);
451 * During the traversal we also do some sanity check.
452 * Trigger the BUG() if there are sides(left/right)
455 if (va
->va_start
< tmp_va
->va_end
&&
456 va
->va_end
<= tmp_va
->va_start
)
457 link
= &(*link
)->rb_left
;
458 else if (va
->va_end
> tmp_va
->va_start
&&
459 va
->va_start
>= tmp_va
->va_end
)
460 link
= &(*link
)->rb_right
;
465 *parent
= &tmp_va
->rb_node
;
469 static __always_inline
struct list_head
*
470 get_va_next_sibling(struct rb_node
*parent
, struct rb_node
**link
)
472 struct list_head
*list
;
474 if (unlikely(!parent
))
476 * The red-black tree where we try to find VA neighbors
477 * before merging or inserting is empty, i.e. it means
478 * there is no free vmap space. Normally it does not
479 * happen but we handle this case anyway.
483 list
= &rb_entry(parent
, struct vmap_area
, rb_node
)->list
;
484 return (&parent
->rb_right
== link
? list
->next
: list
);
487 static __always_inline
void
488 link_va(struct vmap_area
*va
, struct rb_root
*root
,
489 struct rb_node
*parent
, struct rb_node
**link
, struct list_head
*head
)
492 * VA is still not in the list, but we can
493 * identify its future previous list_head node.
495 if (likely(parent
)) {
496 head
= &rb_entry(parent
, struct vmap_area
, rb_node
)->list
;
497 if (&parent
->rb_right
!= link
)
501 /* Insert to the rb-tree */
502 rb_link_node(&va
->rb_node
, parent
, link
);
503 if (root
== &free_vmap_area_root
) {
505 * Some explanation here. Just perform simple insertion
506 * to the tree. We do not set va->subtree_max_size to
507 * its current size before calling rb_insert_augmented().
508 * It is because of we populate the tree from the bottom
509 * to parent levels when the node _is_ in the tree.
511 * Therefore we set subtree_max_size to zero after insertion,
512 * to let __augment_tree_propagate_from() puts everything to
513 * the correct order later on.
515 rb_insert_augmented(&va
->rb_node
,
516 root
, &free_vmap_area_rb_augment_cb
);
517 va
->subtree_max_size
= 0;
519 rb_insert_color(&va
->rb_node
, root
);
522 /* Address-sort this list */
523 list_add(&va
->list
, head
);
526 static __always_inline
void
527 unlink_va(struct vmap_area
*va
, struct rb_root
*root
)
530 * During merging a VA node can be empty, therefore
531 * not linked with the tree nor list. Just check it.
533 if (!RB_EMPTY_NODE(&va
->rb_node
)) {
534 if (root
== &free_vmap_area_root
)
535 rb_erase_augmented(&va
->rb_node
,
536 root
, &free_vmap_area_rb_augment_cb
);
538 rb_erase(&va
->rb_node
, root
);
541 RB_CLEAR_NODE(&va
->rb_node
);
545 #if DEBUG_AUGMENT_PROPAGATE_CHECK
547 augment_tree_propagate_check(struct rb_node
*n
)
549 struct vmap_area
*va
;
550 struct rb_node
*node
;
557 va
= rb_entry(n
, struct vmap_area
, rb_node
);
558 size
= va
->subtree_max_size
;
562 va
= rb_entry(node
, struct vmap_area
, rb_node
);
564 if (get_subtree_max_size(node
->rb_left
) == size
) {
565 node
= node
->rb_left
;
567 if (va_size(va
) == size
) {
572 node
= node
->rb_right
;
577 va
= rb_entry(n
, struct vmap_area
, rb_node
);
578 pr_emerg("tree is corrupted: %lu, %lu\n",
579 va_size(va
), va
->subtree_max_size
);
582 augment_tree_propagate_check(n
->rb_left
);
583 augment_tree_propagate_check(n
->rb_right
);
588 * This function populates subtree_max_size from bottom to upper
589 * levels starting from VA point. The propagation must be done
590 * when VA size is modified by changing its va_start/va_end. Or
591 * in case of newly inserting of VA to the tree.
593 * It means that __augment_tree_propagate_from() must be called:
594 * - After VA has been inserted to the tree(free path);
595 * - After VA has been shrunk(allocation path);
596 * - After VA has been increased(merging path).
598 * Please note that, it does not mean that upper parent nodes
599 * and their subtree_max_size are recalculated all the time up
608 * For example if we modify the node 4, shrinking it to 2, then
609 * no any modification is required. If we shrink the node 2 to 1
610 * its subtree_max_size is updated only, and set to 1. If we shrink
611 * the node 8 to 6, then its subtree_max_size is set to 6 and parent
614 static __always_inline
void
615 augment_tree_propagate_from(struct vmap_area
*va
)
617 struct rb_node
*node
= &va
->rb_node
;
618 unsigned long new_va_sub_max_size
;
621 va
= rb_entry(node
, struct vmap_area
, rb_node
);
622 new_va_sub_max_size
= compute_subtree_max_size(va
);
625 * If the newly calculated maximum available size of the
626 * subtree is equal to the current one, then it means that
627 * the tree is propagated correctly. So we have to stop at
628 * this point to save cycles.
630 if (va
->subtree_max_size
== new_va_sub_max_size
)
633 va
->subtree_max_size
= new_va_sub_max_size
;
634 node
= rb_parent(&va
->rb_node
);
637 #if DEBUG_AUGMENT_PROPAGATE_CHECK
638 augment_tree_propagate_check(free_vmap_area_root
.rb_node
);
643 insert_vmap_area(struct vmap_area
*va
,
644 struct rb_root
*root
, struct list_head
*head
)
646 struct rb_node
**link
;
647 struct rb_node
*parent
;
649 link
= find_va_links(va
, root
, NULL
, &parent
);
650 link_va(va
, root
, parent
, link
, head
);
654 insert_vmap_area_augment(struct vmap_area
*va
,
655 struct rb_node
*from
, struct rb_root
*root
,
656 struct list_head
*head
)
658 struct rb_node
**link
;
659 struct rb_node
*parent
;
662 link
= find_va_links(va
, NULL
, from
, &parent
);
664 link
= find_va_links(va
, root
, NULL
, &parent
);
666 link_va(va
, root
, parent
, link
, head
);
667 augment_tree_propagate_from(va
);
671 * Merge de-allocated chunk of VA memory with previous
672 * and next free blocks. If coalesce is not done a new
673 * free area is inserted. If VA has been merged, it is
676 static __always_inline
void
677 merge_or_add_vmap_area(struct vmap_area
*va
,
678 struct rb_root
*root
, struct list_head
*head
)
680 struct vmap_area
*sibling
;
681 struct list_head
*next
;
682 struct rb_node
**link
;
683 struct rb_node
*parent
;
687 * Find a place in the tree where VA potentially will be
688 * inserted, unless it is merged with its sibling/siblings.
690 link
= find_va_links(va
, root
, NULL
, &parent
);
693 * Get next node of VA to check if merging can be done.
695 next
= get_va_next_sibling(parent
, link
);
696 if (unlikely(next
== NULL
))
702 * |<------VA------>|<-----Next----->|
707 sibling
= list_entry(next
, struct vmap_area
, list
);
708 if (sibling
->va_start
== va
->va_end
) {
709 sibling
->va_start
= va
->va_start
;
711 /* Check and update the tree if needed. */
712 augment_tree_propagate_from(sibling
);
714 /* Remove this VA, it has been merged. */
717 /* Free vmap_area object. */
718 kmem_cache_free(vmap_area_cachep
, va
);
720 /* Point to the new merged area. */
729 * |<-----Prev----->|<------VA------>|
733 if (next
->prev
!= head
) {
734 sibling
= list_entry(next
->prev
, struct vmap_area
, list
);
735 if (sibling
->va_end
== va
->va_start
) {
736 sibling
->va_end
= va
->va_end
;
738 /* Check and update the tree if needed. */
739 augment_tree_propagate_from(sibling
);
741 /* Remove this VA, it has been merged. */
744 /* Free vmap_area object. */
745 kmem_cache_free(vmap_area_cachep
, va
);
753 link_va(va
, root
, parent
, link
, head
);
754 augment_tree_propagate_from(va
);
758 static __always_inline
bool
759 is_within_this_va(struct vmap_area
*va
, unsigned long size
,
760 unsigned long align
, unsigned long vstart
)
762 unsigned long nva_start_addr
;
764 if (va
->va_start
> vstart
)
765 nva_start_addr
= ALIGN(va
->va_start
, align
);
767 nva_start_addr
= ALIGN(vstart
, align
);
769 /* Can be overflowed due to big size or alignment. */
770 if (nva_start_addr
+ size
< nva_start_addr
||
771 nva_start_addr
< vstart
)
774 return (nva_start_addr
+ size
<= va
->va_end
);
778 * Find the first free block(lowest start address) in the tree,
779 * that will accomplish the request corresponding to passing
782 static __always_inline
struct vmap_area
*
783 find_vmap_lowest_match(unsigned long size
,
784 unsigned long align
, unsigned long vstart
)
786 struct vmap_area
*va
;
787 struct rb_node
*node
;
788 unsigned long length
;
790 /* Start from the root. */
791 node
= free_vmap_area_root
.rb_node
;
793 /* Adjust the search size for alignment overhead. */
794 length
= size
+ align
- 1;
797 va
= rb_entry(node
, struct vmap_area
, rb_node
);
799 if (get_subtree_max_size(node
->rb_left
) >= length
&&
800 vstart
< va
->va_start
) {
801 node
= node
->rb_left
;
803 if (is_within_this_va(va
, size
, align
, vstart
))
807 * Does not make sense to go deeper towards the right
808 * sub-tree if it does not have a free block that is
809 * equal or bigger to the requested search length.
811 if (get_subtree_max_size(node
->rb_right
) >= length
) {
812 node
= node
->rb_right
;
817 * OK. We roll back and find the fist right sub-tree,
818 * that will satisfy the search criteria. It can happen
819 * only once due to "vstart" restriction.
821 while ((node
= rb_parent(node
))) {
822 va
= rb_entry(node
, struct vmap_area
, rb_node
);
823 if (is_within_this_va(va
, size
, align
, vstart
))
826 if (get_subtree_max_size(node
->rb_right
) >= length
&&
827 vstart
<= va
->va_start
) {
828 node
= node
->rb_right
;
838 #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
839 #include <linux/random.h>
841 static struct vmap_area
*
842 find_vmap_lowest_linear_match(unsigned long size
,
843 unsigned long align
, unsigned long vstart
)
845 struct vmap_area
*va
;
847 list_for_each_entry(va
, &free_vmap_area_list
, list
) {
848 if (!is_within_this_va(va
, size
, align
, vstart
))
858 find_vmap_lowest_match_check(unsigned long size
)
860 struct vmap_area
*va_1
, *va_2
;
861 unsigned long vstart
;
864 get_random_bytes(&rnd
, sizeof(rnd
));
865 vstart
= VMALLOC_START
+ rnd
;
867 va_1
= find_vmap_lowest_match(size
, 1, vstart
);
868 va_2
= find_vmap_lowest_linear_match(size
, 1, vstart
);
871 pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n",
878 FL_FIT_TYPE
= 1, /* full fit */
879 LE_FIT_TYPE
= 2, /* left edge fit */
880 RE_FIT_TYPE
= 3, /* right edge fit */
881 NE_FIT_TYPE
= 4 /* no edge fit */
884 static __always_inline
enum fit_type
885 classify_va_fit_type(struct vmap_area
*va
,
886 unsigned long nva_start_addr
, unsigned long size
)
890 /* Check if it is within VA. */
891 if (nva_start_addr
< va
->va_start
||
892 nva_start_addr
+ size
> va
->va_end
)
896 if (va
->va_start
== nva_start_addr
) {
897 if (va
->va_end
== nva_start_addr
+ size
)
901 } else if (va
->va_end
== nva_start_addr
+ size
) {
910 static __always_inline
int
911 adjust_va_to_fit_type(struct vmap_area
*va
,
912 unsigned long nva_start_addr
, unsigned long size
,
915 struct vmap_area
*lva
;
917 if (type
== FL_FIT_TYPE
) {
919 * No need to split VA, it fully fits.
925 unlink_va(va
, &free_vmap_area_root
);
926 kmem_cache_free(vmap_area_cachep
, va
);
927 } else if (type
== LE_FIT_TYPE
) {
929 * Split left edge of fit VA.
935 va
->va_start
+= size
;
936 } else if (type
== RE_FIT_TYPE
) {
938 * Split right edge of fit VA.
944 va
->va_end
= nva_start_addr
;
945 } else if (type
== NE_FIT_TYPE
) {
947 * Split no edge of fit VA.
953 lva
= kmem_cache_alloc(vmap_area_cachep
, GFP_NOWAIT
);
958 * Build the remainder.
960 lva
->va_start
= va
->va_start
;
961 lva
->va_end
= nva_start_addr
;
964 * Shrink this VA to remaining size.
966 va
->va_start
= nva_start_addr
+ size
;
971 if (type
!= FL_FIT_TYPE
) {
972 augment_tree_propagate_from(va
);
974 if (type
== NE_FIT_TYPE
)
975 insert_vmap_area_augment(lva
, &va
->rb_node
,
976 &free_vmap_area_root
, &free_vmap_area_list
);
983 * Returns a start address of the newly allocated area, if success.
984 * Otherwise a vend is returned that indicates failure.
986 static __always_inline
unsigned long
987 __alloc_vmap_area(unsigned long size
, unsigned long align
,
988 unsigned long vstart
, unsigned long vend
, int node
)
990 unsigned long nva_start_addr
;
991 struct vmap_area
*va
;
995 va
= find_vmap_lowest_match(size
, align
, vstart
);
999 if (va
->va_start
> vstart
)
1000 nva_start_addr
= ALIGN(va
->va_start
, align
);
1002 nva_start_addr
= ALIGN(vstart
, align
);
1004 /* Check the "vend" restriction. */
1005 if (nva_start_addr
+ size
> vend
)
1008 /* Classify what we have found. */
1009 type
= classify_va_fit_type(va
, nva_start_addr
, size
);
1010 if (WARN_ON_ONCE(type
== NOTHING_FIT
))
1013 /* Update the free vmap_area. */
1014 ret
= adjust_va_to_fit_type(va
, nva_start_addr
, size
, type
);
1018 #if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
1019 find_vmap_lowest_match_check(size
);
1022 return nva_start_addr
;
1026 * Allocate a region of KVA of the specified size and alignment, within the
1029 static struct vmap_area
*alloc_vmap_area(unsigned long size
,
1030 unsigned long align
,
1031 unsigned long vstart
, unsigned long vend
,
1032 int node
, gfp_t gfp_mask
)
1034 struct vmap_area
*va
;
1039 BUG_ON(offset_in_page(size
));
1040 BUG_ON(!is_power_of_2(align
));
1042 if (unlikely(!vmap_initialized
))
1043 return ERR_PTR(-EBUSY
);
1047 va
= kmem_cache_alloc_node(vmap_area_cachep
,
1048 gfp_mask
& GFP_RECLAIM_MASK
, node
);
1050 return ERR_PTR(-ENOMEM
);
1053 * Only scan the relevant parts containing pointers to other objects
1054 * to avoid false negatives.
1056 kmemleak_scan_area(&va
->rb_node
, SIZE_MAX
, gfp_mask
& GFP_RECLAIM_MASK
);
1059 spin_lock(&vmap_area_lock
);
1062 * If an allocation fails, the "vend" address is
1063 * returned. Therefore trigger the overflow path.
1065 addr
= __alloc_vmap_area(size
, align
, vstart
, vend
, node
);
1066 if (unlikely(addr
== vend
))
1069 va
->va_start
= addr
;
1070 va
->va_end
= addr
+ size
;
1072 insert_vmap_area(va
, &vmap_area_root
, &vmap_area_list
);
1074 spin_unlock(&vmap_area_lock
);
1076 BUG_ON(!IS_ALIGNED(va
->va_start
, align
));
1077 BUG_ON(va
->va_start
< vstart
);
1078 BUG_ON(va
->va_end
> vend
);
1083 spin_unlock(&vmap_area_lock
);
1085 purge_vmap_area_lazy();
1090 if (gfpflags_allow_blocking(gfp_mask
)) {
1091 unsigned long freed
= 0;
1092 blocking_notifier_call_chain(&vmap_notify_list
, 0, &freed
);
1099 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit())
1100 pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n",
1103 kmem_cache_free(vmap_area_cachep
, va
);
1104 return ERR_PTR(-EBUSY
);
1107 int register_vmap_purge_notifier(struct notifier_block
*nb
)
1109 return blocking_notifier_chain_register(&vmap_notify_list
, nb
);
1111 EXPORT_SYMBOL_GPL(register_vmap_purge_notifier
);
1113 int unregister_vmap_purge_notifier(struct notifier_block
*nb
)
1115 return blocking_notifier_chain_unregister(&vmap_notify_list
, nb
);
1117 EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier
);
1119 static void __free_vmap_area(struct vmap_area
*va
)
1121 BUG_ON(RB_EMPTY_NODE(&va
->rb_node
));
1124 * Remove from the busy tree/list.
1126 unlink_va(va
, &vmap_area_root
);
1129 * Merge VA with its neighbors, otherwise just add it.
1131 merge_or_add_vmap_area(va
,
1132 &free_vmap_area_root
, &free_vmap_area_list
);
1136 * Free a region of KVA allocated by alloc_vmap_area
1138 static void free_vmap_area(struct vmap_area
*va
)
1140 spin_lock(&vmap_area_lock
);
1141 __free_vmap_area(va
);
1142 spin_unlock(&vmap_area_lock
);
1146 * Clear the pagetable entries of a given vmap_area
1148 static void unmap_vmap_area(struct vmap_area
*va
)
1150 vunmap_page_range(va
->va_start
, va
->va_end
);
1154 * lazy_max_pages is the maximum amount of virtual address space we gather up
1155 * before attempting to purge with a TLB flush.
1157 * There is a tradeoff here: a larger number will cover more kernel page tables
1158 * and take slightly longer to purge, but it will linearly reduce the number of
1159 * global TLB flushes that must be performed. It would seem natural to scale
1160 * this number up linearly with the number of CPUs (because vmapping activity
1161 * could also scale linearly with the number of CPUs), however it is likely
1162 * that in practice, workloads might be constrained in other ways that mean
1163 * vmap activity will not scale linearly with CPUs. Also, I want to be
1164 * conservative and not introduce a big latency on huge systems, so go with
1165 * a less aggressive log scale. It will still be an improvement over the old
1166 * code, and it will be simple to change the scale factor if we find that it
1167 * becomes a problem on bigger systems.
1169 static unsigned long lazy_max_pages(void)
1173 log
= fls(num_online_cpus());
1175 return log
* (32UL * 1024 * 1024 / PAGE_SIZE
);
1178 static atomic_long_t vmap_lazy_nr
= ATOMIC_LONG_INIT(0);
1181 * Serialize vmap purging. There is no actual criticial section protected
1182 * by this look, but we want to avoid concurrent calls for performance
1183 * reasons and to make the pcpu_get_vm_areas more deterministic.
1185 static DEFINE_MUTEX(vmap_purge_lock
);
1187 /* for per-CPU blocks */
1188 static void purge_fragmented_blocks_allcpus(void);
1191 * called before a call to iounmap() if the caller wants vm_area_struct's
1192 * immediately freed.
1194 void set_iounmap_nonlazy(void)
1196 atomic_long_set(&vmap_lazy_nr
, lazy_max_pages()+1);
1200 * Purges all lazily-freed vmap areas.
1202 static bool __purge_vmap_area_lazy(unsigned long start
, unsigned long end
)
1204 unsigned long resched_threshold
;
1205 struct llist_node
*valist
;
1206 struct vmap_area
*va
;
1207 struct vmap_area
*n_va
;
1209 lockdep_assert_held(&vmap_purge_lock
);
1211 valist
= llist_del_all(&vmap_purge_list
);
1212 if (unlikely(valist
== NULL
))
1216 * TODO: to calculate a flush range without looping.
1217 * The list can be up to lazy_max_pages() elements.
1219 llist_for_each_entry(va
, valist
, purge_list
) {
1220 if (va
->va_start
< start
)
1221 start
= va
->va_start
;
1222 if (va
->va_end
> end
)
1226 flush_tlb_kernel_range(start
, end
);
1227 resched_threshold
= lazy_max_pages() << 1;
1229 spin_lock(&vmap_area_lock
);
1230 llist_for_each_entry_safe(va
, n_va
, valist
, purge_list
) {
1231 unsigned long nr
= (va
->va_end
- va
->va_start
) >> PAGE_SHIFT
;
1233 __free_vmap_area(va
);
1234 atomic_long_sub(nr
, &vmap_lazy_nr
);
1236 if (atomic_long_read(&vmap_lazy_nr
) < resched_threshold
)
1237 cond_resched_lock(&vmap_area_lock
);
1239 spin_unlock(&vmap_area_lock
);
1244 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
1245 * is already purging.
1247 static void try_purge_vmap_area_lazy(void)
1249 if (mutex_trylock(&vmap_purge_lock
)) {
1250 __purge_vmap_area_lazy(ULONG_MAX
, 0);
1251 mutex_unlock(&vmap_purge_lock
);
1256 * Kick off a purge of the outstanding lazy areas.
1258 static void purge_vmap_area_lazy(void)
1260 mutex_lock(&vmap_purge_lock
);
1261 purge_fragmented_blocks_allcpus();
1262 __purge_vmap_area_lazy(ULONG_MAX
, 0);
1263 mutex_unlock(&vmap_purge_lock
);
1267 * Free a vmap area, caller ensuring that the area has been unmapped
1268 * and flush_cache_vunmap had been called for the correct range
1271 static void free_vmap_area_noflush(struct vmap_area
*va
)
1273 unsigned long nr_lazy
;
1275 nr_lazy
= atomic_long_add_return((va
->va_end
- va
->va_start
) >>
1276 PAGE_SHIFT
, &vmap_lazy_nr
);
1278 /* After this point, we may free va at any time */
1279 llist_add(&va
->purge_list
, &vmap_purge_list
);
1281 if (unlikely(nr_lazy
> lazy_max_pages()))
1282 try_purge_vmap_area_lazy();
1286 * Free and unmap a vmap area
1288 static void free_unmap_vmap_area(struct vmap_area
*va
)
1290 flush_cache_vunmap(va
->va_start
, va
->va_end
);
1291 unmap_vmap_area(va
);
1292 if (debug_pagealloc_enabled())
1293 flush_tlb_kernel_range(va
->va_start
, va
->va_end
);
1295 free_vmap_area_noflush(va
);
1298 static struct vmap_area
*find_vmap_area(unsigned long addr
)
1300 struct vmap_area
*va
;
1302 spin_lock(&vmap_area_lock
);
1303 va
= __find_vmap_area(addr
);
1304 spin_unlock(&vmap_area_lock
);
1309 /*** Per cpu kva allocator ***/
1312 * vmap space is limited especially on 32 bit architectures. Ensure there is
1313 * room for at least 16 percpu vmap blocks per CPU.
1316 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
1317 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
1318 * instead (we just need a rough idea)
1320 #if BITS_PER_LONG == 32
1321 #define VMALLOC_SPACE (128UL*1024*1024)
1323 #define VMALLOC_SPACE (128UL*1024*1024*1024)
1326 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
1327 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
1328 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
1329 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
1330 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
1331 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
1332 #define VMAP_BBMAP_BITS \
1333 VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
1334 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
1335 VMALLOC_PAGES / roundup_pow_of_two(NR_CPUS) / 16))
1337 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
1339 struct vmap_block_queue
{
1341 struct list_head free
;
1346 struct vmap_area
*va
;
1347 unsigned long free
, dirty
;
1348 unsigned long dirty_min
, dirty_max
; /*< dirty range */
1349 struct list_head free_list
;
1350 struct rcu_head rcu_head
;
1351 struct list_head purge
;
1354 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
1355 static DEFINE_PER_CPU(struct vmap_block_queue
, vmap_block_queue
);
1358 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
1359 * in the free path. Could get rid of this if we change the API to return a
1360 * "cookie" from alloc, to be passed to free. But no big deal yet.
1362 static DEFINE_SPINLOCK(vmap_block_tree_lock
);
1363 static RADIX_TREE(vmap_block_tree
, GFP_ATOMIC
);
1366 * We should probably have a fallback mechanism to allocate virtual memory
1367 * out of partially filled vmap blocks. However vmap block sizing should be
1368 * fairly reasonable according to the vmalloc size, so it shouldn't be a
1372 static unsigned long addr_to_vb_idx(unsigned long addr
)
1374 addr
-= VMALLOC_START
& ~(VMAP_BLOCK_SIZE
-1);
1375 addr
/= VMAP_BLOCK_SIZE
;
1379 static void *vmap_block_vaddr(unsigned long va_start
, unsigned long pages_off
)
1383 addr
= va_start
+ (pages_off
<< PAGE_SHIFT
);
1384 BUG_ON(addr_to_vb_idx(addr
) != addr_to_vb_idx(va_start
));
1385 return (void *)addr
;
1389 * new_vmap_block - allocates new vmap_block and occupies 2^order pages in this
1390 * block. Of course pages number can't exceed VMAP_BBMAP_BITS
1391 * @order: how many 2^order pages should be occupied in newly allocated block
1392 * @gfp_mask: flags for the page level allocator
1394 * Return: virtual address in a newly allocated block or ERR_PTR(-errno)
1396 static void *new_vmap_block(unsigned int order
, gfp_t gfp_mask
)
1398 struct vmap_block_queue
*vbq
;
1399 struct vmap_block
*vb
;
1400 struct vmap_area
*va
;
1401 unsigned long vb_idx
;
1405 node
= numa_node_id();
1407 vb
= kmalloc_node(sizeof(struct vmap_block
),
1408 gfp_mask
& GFP_RECLAIM_MASK
, node
);
1410 return ERR_PTR(-ENOMEM
);
1412 va
= alloc_vmap_area(VMAP_BLOCK_SIZE
, VMAP_BLOCK_SIZE
,
1413 VMALLOC_START
, VMALLOC_END
,
1417 return ERR_CAST(va
);
1420 err
= radix_tree_preload(gfp_mask
);
1421 if (unlikely(err
)) {
1424 return ERR_PTR(err
);
1427 vaddr
= vmap_block_vaddr(va
->va_start
, 0);
1428 spin_lock_init(&vb
->lock
);
1430 /* At least something should be left free */
1431 BUG_ON(VMAP_BBMAP_BITS
<= (1UL << order
));
1432 vb
->free
= VMAP_BBMAP_BITS
- (1UL << order
);
1434 vb
->dirty_min
= VMAP_BBMAP_BITS
;
1436 INIT_LIST_HEAD(&vb
->free_list
);
1438 vb_idx
= addr_to_vb_idx(va
->va_start
);
1439 spin_lock(&vmap_block_tree_lock
);
1440 err
= radix_tree_insert(&vmap_block_tree
, vb_idx
, vb
);
1441 spin_unlock(&vmap_block_tree_lock
);
1443 radix_tree_preload_end();
1445 vbq
= &get_cpu_var(vmap_block_queue
);
1446 spin_lock(&vbq
->lock
);
1447 list_add_tail_rcu(&vb
->free_list
, &vbq
->free
);
1448 spin_unlock(&vbq
->lock
);
1449 put_cpu_var(vmap_block_queue
);
1454 static void free_vmap_block(struct vmap_block
*vb
)
1456 struct vmap_block
*tmp
;
1457 unsigned long vb_idx
;
1459 vb_idx
= addr_to_vb_idx(vb
->va
->va_start
);
1460 spin_lock(&vmap_block_tree_lock
);
1461 tmp
= radix_tree_delete(&vmap_block_tree
, vb_idx
);
1462 spin_unlock(&vmap_block_tree_lock
);
1465 free_vmap_area_noflush(vb
->va
);
1466 kfree_rcu(vb
, rcu_head
);
1469 static void purge_fragmented_blocks(int cpu
)
1472 struct vmap_block
*vb
;
1473 struct vmap_block
*n_vb
;
1474 struct vmap_block_queue
*vbq
= &per_cpu(vmap_block_queue
, cpu
);
1477 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
1479 if (!(vb
->free
+ vb
->dirty
== VMAP_BBMAP_BITS
&& vb
->dirty
!= VMAP_BBMAP_BITS
))
1482 spin_lock(&vb
->lock
);
1483 if (vb
->free
+ vb
->dirty
== VMAP_BBMAP_BITS
&& vb
->dirty
!= VMAP_BBMAP_BITS
) {
1484 vb
->free
= 0; /* prevent further allocs after releasing lock */
1485 vb
->dirty
= VMAP_BBMAP_BITS
; /* prevent purging it again */
1487 vb
->dirty_max
= VMAP_BBMAP_BITS
;
1488 spin_lock(&vbq
->lock
);
1489 list_del_rcu(&vb
->free_list
);
1490 spin_unlock(&vbq
->lock
);
1491 spin_unlock(&vb
->lock
);
1492 list_add_tail(&vb
->purge
, &purge
);
1494 spin_unlock(&vb
->lock
);
1498 list_for_each_entry_safe(vb
, n_vb
, &purge
, purge
) {
1499 list_del(&vb
->purge
);
1500 free_vmap_block(vb
);
1504 static void purge_fragmented_blocks_allcpus(void)
1508 for_each_possible_cpu(cpu
)
1509 purge_fragmented_blocks(cpu
);
1512 static void *vb_alloc(unsigned long size
, gfp_t gfp_mask
)
1514 struct vmap_block_queue
*vbq
;
1515 struct vmap_block
*vb
;
1519 BUG_ON(offset_in_page(size
));
1520 BUG_ON(size
> PAGE_SIZE
*VMAP_MAX_ALLOC
);
1521 if (WARN_ON(size
== 0)) {
1523 * Allocating 0 bytes isn't what caller wants since
1524 * get_order(0) returns funny result. Just warn and terminate
1529 order
= get_order(size
);
1532 vbq
= &get_cpu_var(vmap_block_queue
);
1533 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
1534 unsigned long pages_off
;
1536 spin_lock(&vb
->lock
);
1537 if (vb
->free
< (1UL << order
)) {
1538 spin_unlock(&vb
->lock
);
1542 pages_off
= VMAP_BBMAP_BITS
- vb
->free
;
1543 vaddr
= vmap_block_vaddr(vb
->va
->va_start
, pages_off
);
1544 vb
->free
-= 1UL << order
;
1545 if (vb
->free
== 0) {
1546 spin_lock(&vbq
->lock
);
1547 list_del_rcu(&vb
->free_list
);
1548 spin_unlock(&vbq
->lock
);
1551 spin_unlock(&vb
->lock
);
1555 put_cpu_var(vmap_block_queue
);
1558 /* Allocate new block if nothing was found */
1560 vaddr
= new_vmap_block(order
, gfp_mask
);
1565 static void vb_free(const void *addr
, unsigned long size
)
1567 unsigned long offset
;
1568 unsigned long vb_idx
;
1570 struct vmap_block
*vb
;
1572 BUG_ON(offset_in_page(size
));
1573 BUG_ON(size
> PAGE_SIZE
*VMAP_MAX_ALLOC
);
1575 flush_cache_vunmap((unsigned long)addr
, (unsigned long)addr
+ size
);
1577 order
= get_order(size
);
1579 offset
= (unsigned long)addr
& (VMAP_BLOCK_SIZE
- 1);
1580 offset
>>= PAGE_SHIFT
;
1582 vb_idx
= addr_to_vb_idx((unsigned long)addr
);
1584 vb
= radix_tree_lookup(&vmap_block_tree
, vb_idx
);
1588 vunmap_page_range((unsigned long)addr
, (unsigned long)addr
+ size
);
1590 if (debug_pagealloc_enabled())
1591 flush_tlb_kernel_range((unsigned long)addr
,
1592 (unsigned long)addr
+ size
);
1594 spin_lock(&vb
->lock
);
1596 /* Expand dirty range */
1597 vb
->dirty_min
= min(vb
->dirty_min
, offset
);
1598 vb
->dirty_max
= max(vb
->dirty_max
, offset
+ (1UL << order
));
1600 vb
->dirty
+= 1UL << order
;
1601 if (vb
->dirty
== VMAP_BBMAP_BITS
) {
1603 spin_unlock(&vb
->lock
);
1604 free_vmap_block(vb
);
1606 spin_unlock(&vb
->lock
);
1609 static void _vm_unmap_aliases(unsigned long start
, unsigned long end
, int flush
)
1613 if (unlikely(!vmap_initialized
))
1618 for_each_possible_cpu(cpu
) {
1619 struct vmap_block_queue
*vbq
= &per_cpu(vmap_block_queue
, cpu
);
1620 struct vmap_block
*vb
;
1623 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
1624 spin_lock(&vb
->lock
);
1626 unsigned long va_start
= vb
->va
->va_start
;
1629 s
= va_start
+ (vb
->dirty_min
<< PAGE_SHIFT
);
1630 e
= va_start
+ (vb
->dirty_max
<< PAGE_SHIFT
);
1632 start
= min(s
, start
);
1637 spin_unlock(&vb
->lock
);
1642 mutex_lock(&vmap_purge_lock
);
1643 purge_fragmented_blocks_allcpus();
1644 if (!__purge_vmap_area_lazy(start
, end
) && flush
)
1645 flush_tlb_kernel_range(start
, end
);
1646 mutex_unlock(&vmap_purge_lock
);
1650 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
1652 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
1653 * to amortize TLB flushing overheads. What this means is that any page you
1654 * have now, may, in a former life, have been mapped into kernel virtual
1655 * address by the vmap layer and so there might be some CPUs with TLB entries
1656 * still referencing that page (additional to the regular 1:1 kernel mapping).
1658 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
1659 * be sure that none of the pages we have control over will have any aliases
1660 * from the vmap layer.
1662 void vm_unmap_aliases(void)
1664 unsigned long start
= ULONG_MAX
, end
= 0;
1667 _vm_unmap_aliases(start
, end
, flush
);
1669 EXPORT_SYMBOL_GPL(vm_unmap_aliases
);
1672 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1673 * @mem: the pointer returned by vm_map_ram
1674 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1676 void vm_unmap_ram(const void *mem
, unsigned int count
)
1678 unsigned long size
= (unsigned long)count
<< PAGE_SHIFT
;
1679 unsigned long addr
= (unsigned long)mem
;
1680 struct vmap_area
*va
;
1684 BUG_ON(addr
< VMALLOC_START
);
1685 BUG_ON(addr
> VMALLOC_END
);
1686 BUG_ON(!PAGE_ALIGNED(addr
));
1688 if (likely(count
<= VMAP_MAX_ALLOC
)) {
1689 debug_check_no_locks_freed(mem
, size
);
1694 va
= find_vmap_area(addr
);
1696 debug_check_no_locks_freed((void *)va
->va_start
,
1697 (va
->va_end
- va
->va_start
));
1698 free_unmap_vmap_area(va
);
1700 EXPORT_SYMBOL(vm_unmap_ram
);
1703 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1704 * @pages: an array of pointers to the pages to be mapped
1705 * @count: number of pages
1706 * @node: prefer to allocate data structures on this node
1707 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
1709 * If you use this function for less than VMAP_MAX_ALLOC pages, it could be
1710 * faster than vmap so it's good. But if you mix long-life and short-life
1711 * objects with vm_map_ram(), it could consume lots of address space through
1712 * fragmentation (especially on a 32bit machine). You could see failures in
1713 * the end. Please use this function for short-lived objects.
1715 * Returns: a pointer to the address that has been mapped, or %NULL on failure
1717 void *vm_map_ram(struct page
**pages
, unsigned int count
, int node
, pgprot_t prot
)
1719 unsigned long size
= (unsigned long)count
<< PAGE_SHIFT
;
1723 if (likely(count
<= VMAP_MAX_ALLOC
)) {
1724 mem
= vb_alloc(size
, GFP_KERNEL
);
1727 addr
= (unsigned long)mem
;
1729 struct vmap_area
*va
;
1730 va
= alloc_vmap_area(size
, PAGE_SIZE
,
1731 VMALLOC_START
, VMALLOC_END
, node
, GFP_KERNEL
);
1735 addr
= va
->va_start
;
1738 if (vmap_page_range(addr
, addr
+ size
, prot
, pages
) < 0) {
1739 vm_unmap_ram(mem
, count
);
1744 EXPORT_SYMBOL(vm_map_ram
);
1746 static struct vm_struct
*vmlist __initdata
;
1749 * vm_area_add_early - add vmap area early during boot
1750 * @vm: vm_struct to add
1752 * This function is used to add fixed kernel vm area to vmlist before
1753 * vmalloc_init() is called. @vm->addr, @vm->size, and @vm->flags
1754 * should contain proper values and the other fields should be zero.
1756 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1758 void __init
vm_area_add_early(struct vm_struct
*vm
)
1760 struct vm_struct
*tmp
, **p
;
1762 BUG_ON(vmap_initialized
);
1763 for (p
= &vmlist
; (tmp
= *p
) != NULL
; p
= &tmp
->next
) {
1764 if (tmp
->addr
>= vm
->addr
) {
1765 BUG_ON(tmp
->addr
< vm
->addr
+ vm
->size
);
1768 BUG_ON(tmp
->addr
+ tmp
->size
> vm
->addr
);
1775 * vm_area_register_early - register vmap area early during boot
1776 * @vm: vm_struct to register
1777 * @align: requested alignment
1779 * This function is used to register kernel vm area before
1780 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1781 * proper values on entry and other fields should be zero. On return,
1782 * vm->addr contains the allocated address.
1784 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1786 void __init
vm_area_register_early(struct vm_struct
*vm
, size_t align
)
1788 static size_t vm_init_off __initdata
;
1791 addr
= ALIGN(VMALLOC_START
+ vm_init_off
, align
);
1792 vm_init_off
= PFN_ALIGN(addr
+ vm
->size
) - VMALLOC_START
;
1794 vm
->addr
= (void *)addr
;
1796 vm_area_add_early(vm
);
1799 static void vmap_init_free_space(void)
1801 unsigned long vmap_start
= 1;
1802 const unsigned long vmap_end
= ULONG_MAX
;
1803 struct vmap_area
*busy
, *free
;
1807 * -|-----|.....|-----|-----|-----|.....|-
1809 * |<--------------------------------->|
1811 list_for_each_entry(busy
, &vmap_area_list
, list
) {
1812 if (busy
->va_start
- vmap_start
> 0) {
1813 free
= kmem_cache_zalloc(vmap_area_cachep
, GFP_NOWAIT
);
1814 if (!WARN_ON_ONCE(!free
)) {
1815 free
->va_start
= vmap_start
;
1816 free
->va_end
= busy
->va_start
;
1818 insert_vmap_area_augment(free
, NULL
,
1819 &free_vmap_area_root
,
1820 &free_vmap_area_list
);
1824 vmap_start
= busy
->va_end
;
1827 if (vmap_end
- vmap_start
> 0) {
1828 free
= kmem_cache_zalloc(vmap_area_cachep
, GFP_NOWAIT
);
1829 if (!WARN_ON_ONCE(!free
)) {
1830 free
->va_start
= vmap_start
;
1831 free
->va_end
= vmap_end
;
1833 insert_vmap_area_augment(free
, NULL
,
1834 &free_vmap_area_root
,
1835 &free_vmap_area_list
);
1840 void __init
vmalloc_init(void)
1842 struct vmap_area
*va
;
1843 struct vm_struct
*tmp
;
1847 * Create the cache for vmap_area objects.
1849 vmap_area_cachep
= KMEM_CACHE(vmap_area
, SLAB_PANIC
);
1851 for_each_possible_cpu(i
) {
1852 struct vmap_block_queue
*vbq
;
1853 struct vfree_deferred
*p
;
1855 vbq
= &per_cpu(vmap_block_queue
, i
);
1856 spin_lock_init(&vbq
->lock
);
1857 INIT_LIST_HEAD(&vbq
->free
);
1858 p
= &per_cpu(vfree_deferred
, i
);
1859 init_llist_head(&p
->list
);
1860 INIT_WORK(&p
->wq
, free_work
);
1863 /* Import existing vmlist entries. */
1864 for (tmp
= vmlist
; tmp
; tmp
= tmp
->next
) {
1865 va
= kmem_cache_zalloc(vmap_area_cachep
, GFP_NOWAIT
);
1866 if (WARN_ON_ONCE(!va
))
1869 va
->flags
= VM_VM_AREA
;
1870 va
->va_start
= (unsigned long)tmp
->addr
;
1871 va
->va_end
= va
->va_start
+ tmp
->size
;
1873 insert_vmap_area(va
, &vmap_area_root
, &vmap_area_list
);
1877 * Now we can initialize a free vmap space.
1879 vmap_init_free_space();
1880 vmap_initialized
= true;
1884 * map_kernel_range_noflush - map kernel VM area with the specified pages
1885 * @addr: start of the VM area to map
1886 * @size: size of the VM area to map
1887 * @prot: page protection flags to use
1888 * @pages: pages to map
1890 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1891 * specify should have been allocated using get_vm_area() and its
1895 * This function does NOT do any cache flushing. The caller is
1896 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1897 * before calling this function.
1900 * The number of pages mapped on success, -errno on failure.
1902 int map_kernel_range_noflush(unsigned long addr
, unsigned long size
,
1903 pgprot_t prot
, struct page
**pages
)
1905 return vmap_page_range_noflush(addr
, addr
+ size
, prot
, pages
);
1909 * unmap_kernel_range_noflush - unmap kernel VM area
1910 * @addr: start of the VM area to unmap
1911 * @size: size of the VM area to unmap
1913 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1914 * specify should have been allocated using get_vm_area() and its
1918 * This function does NOT do any cache flushing. The caller is
1919 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1920 * before calling this function and flush_tlb_kernel_range() after.
1922 void unmap_kernel_range_noflush(unsigned long addr
, unsigned long size
)
1924 vunmap_page_range(addr
, addr
+ size
);
1926 EXPORT_SYMBOL_GPL(unmap_kernel_range_noflush
);
1929 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1930 * @addr: start of the VM area to unmap
1931 * @size: size of the VM area to unmap
1933 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1934 * the unmapping and tlb after.
1936 void unmap_kernel_range(unsigned long addr
, unsigned long size
)
1938 unsigned long end
= addr
+ size
;
1940 flush_cache_vunmap(addr
, end
);
1941 vunmap_page_range(addr
, end
);
1942 flush_tlb_kernel_range(addr
, end
);
1944 EXPORT_SYMBOL_GPL(unmap_kernel_range
);
1946 int map_vm_area(struct vm_struct
*area
, pgprot_t prot
, struct page
**pages
)
1948 unsigned long addr
= (unsigned long)area
->addr
;
1949 unsigned long end
= addr
+ get_vm_area_size(area
);
1952 err
= vmap_page_range(addr
, end
, prot
, pages
);
1954 return err
> 0 ? 0 : err
;
1956 EXPORT_SYMBOL_GPL(map_vm_area
);
1958 static void setup_vmalloc_vm(struct vm_struct
*vm
, struct vmap_area
*va
,
1959 unsigned long flags
, const void *caller
)
1961 spin_lock(&vmap_area_lock
);
1963 vm
->addr
= (void *)va
->va_start
;
1964 vm
->size
= va
->va_end
- va
->va_start
;
1965 vm
->caller
= caller
;
1967 va
->flags
|= VM_VM_AREA
;
1968 spin_unlock(&vmap_area_lock
);
1971 static void clear_vm_uninitialized_flag(struct vm_struct
*vm
)
1974 * Before removing VM_UNINITIALIZED,
1975 * we should make sure that vm has proper values.
1976 * Pair with smp_rmb() in show_numa_info().
1979 vm
->flags
&= ~VM_UNINITIALIZED
;
1982 static struct vm_struct
*__get_vm_area_node(unsigned long size
,
1983 unsigned long align
, unsigned long flags
, unsigned long start
,
1984 unsigned long end
, int node
, gfp_t gfp_mask
, const void *caller
)
1986 struct vmap_area
*va
;
1987 struct vm_struct
*area
;
1989 BUG_ON(in_interrupt());
1990 size
= PAGE_ALIGN(size
);
1991 if (unlikely(!size
))
1994 if (flags
& VM_IOREMAP
)
1995 align
= 1ul << clamp_t(int, get_count_order_long(size
),
1996 PAGE_SHIFT
, IOREMAP_MAX_ORDER
);
1998 area
= kzalloc_node(sizeof(*area
), gfp_mask
& GFP_RECLAIM_MASK
, node
);
1999 if (unlikely(!area
))
2002 if (!(flags
& VM_NO_GUARD
))
2005 va
= alloc_vmap_area(size
, align
, start
, end
, node
, gfp_mask
);
2011 setup_vmalloc_vm(area
, va
, flags
, caller
);
2016 struct vm_struct
*__get_vm_area(unsigned long size
, unsigned long flags
,
2017 unsigned long start
, unsigned long end
)
2019 return __get_vm_area_node(size
, 1, flags
, start
, end
, NUMA_NO_NODE
,
2020 GFP_KERNEL
, __builtin_return_address(0));
2022 EXPORT_SYMBOL_GPL(__get_vm_area
);
2024 struct vm_struct
*__get_vm_area_caller(unsigned long size
, unsigned long flags
,
2025 unsigned long start
, unsigned long end
,
2028 return __get_vm_area_node(size
, 1, flags
, start
, end
, NUMA_NO_NODE
,
2029 GFP_KERNEL
, caller
);
2033 * get_vm_area - reserve a contiguous kernel virtual area
2034 * @size: size of the area
2035 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
2037 * Search an area of @size in the kernel virtual mapping area,
2038 * and reserved it for out purposes. Returns the area descriptor
2039 * on success or %NULL on failure.
2041 * Return: the area descriptor on success or %NULL on failure.
2043 struct vm_struct
*get_vm_area(unsigned long size
, unsigned long flags
)
2045 return __get_vm_area_node(size
, 1, flags
, VMALLOC_START
, VMALLOC_END
,
2046 NUMA_NO_NODE
, GFP_KERNEL
,
2047 __builtin_return_address(0));
2050 struct vm_struct
*get_vm_area_caller(unsigned long size
, unsigned long flags
,
2053 return __get_vm_area_node(size
, 1, flags
, VMALLOC_START
, VMALLOC_END
,
2054 NUMA_NO_NODE
, GFP_KERNEL
, caller
);
2058 * find_vm_area - find a continuous kernel virtual area
2059 * @addr: base address
2061 * Search for the kernel VM area starting at @addr, and return it.
2062 * It is up to the caller to do all required locking to keep the returned
2065 * Return: pointer to the found area or %NULL on faulure
2067 struct vm_struct
*find_vm_area(const void *addr
)
2069 struct vmap_area
*va
;
2071 va
= find_vmap_area((unsigned long)addr
);
2072 if (va
&& va
->flags
& VM_VM_AREA
)
2079 * remove_vm_area - find and remove a continuous kernel virtual area
2080 * @addr: base address
2082 * Search for the kernel VM area starting at @addr, and remove it.
2083 * This function returns the found VM area, but using it is NOT safe
2084 * on SMP machines, except for its size or flags.
2086 * Return: pointer to the found area or %NULL on faulure
2088 struct vm_struct
*remove_vm_area(const void *addr
)
2090 struct vmap_area
*va
;
2094 va
= find_vmap_area((unsigned long)addr
);
2095 if (va
&& va
->flags
& VM_VM_AREA
) {
2096 struct vm_struct
*vm
= va
->vm
;
2098 spin_lock(&vmap_area_lock
);
2100 va
->flags
&= ~VM_VM_AREA
;
2101 va
->flags
|= VM_LAZY_FREE
;
2102 spin_unlock(&vmap_area_lock
);
2104 kasan_free_shadow(vm
);
2105 free_unmap_vmap_area(va
);
2112 static inline void set_area_direct_map(const struct vm_struct
*area
,
2113 int (*set_direct_map
)(struct page
*page
))
2117 for (i
= 0; i
< area
->nr_pages
; i
++)
2118 if (page_address(area
->pages
[i
]))
2119 set_direct_map(area
->pages
[i
]);
2122 /* Handle removing and resetting vm mappings related to the vm_struct. */
2123 static void vm_remove_mappings(struct vm_struct
*area
, int deallocate_pages
)
2125 unsigned long addr
= (unsigned long)area
->addr
;
2126 unsigned long start
= ULONG_MAX
, end
= 0;
2127 int flush_reset
= area
->flags
& VM_FLUSH_RESET_PERMS
;
2131 * The below block can be removed when all architectures that have
2132 * direct map permissions also have set_direct_map_() implementations.
2133 * This is concerned with resetting the direct map any an vm alias with
2134 * execute permissions, without leaving a RW+X window.
2136 if (flush_reset
&& !IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP
)) {
2137 set_memory_nx(addr
, area
->nr_pages
);
2138 set_memory_rw(addr
, area
->nr_pages
);
2141 remove_vm_area(area
->addr
);
2143 /* If this is not VM_FLUSH_RESET_PERMS memory, no need for the below. */
2148 * If not deallocating pages, just do the flush of the VM area and
2151 if (!deallocate_pages
) {
2157 * If execution gets here, flush the vm mapping and reset the direct
2158 * map. Find the start and end range of the direct mappings to make sure
2159 * the vm_unmap_aliases() flush includes the direct map.
2161 for (i
= 0; i
< area
->nr_pages
; i
++) {
2162 if (page_address(area
->pages
[i
])) {
2163 start
= min(addr
, start
);
2164 end
= max(addr
, end
);
2169 * Set direct map to something invalid so that it won't be cached if
2170 * there are any accesses after the TLB flush, then flush the TLB and
2171 * reset the direct map permissions to the default.
2173 set_area_direct_map(area
, set_direct_map_invalid_noflush
);
2174 _vm_unmap_aliases(start
, end
, 1);
2175 set_area_direct_map(area
, set_direct_map_default_noflush
);
2178 static void __vunmap(const void *addr
, int deallocate_pages
)
2180 struct vm_struct
*area
;
2185 if (WARN(!PAGE_ALIGNED(addr
), "Trying to vfree() bad address (%p)\n",
2189 area
= find_vm_area(addr
);
2190 if (unlikely(!area
)) {
2191 WARN(1, KERN_ERR
"Trying to vfree() nonexistent vm area (%p)\n",
2196 debug_check_no_locks_freed(area
->addr
, get_vm_area_size(area
));
2197 debug_check_no_obj_freed(area
->addr
, get_vm_area_size(area
));
2199 vm_remove_mappings(area
, deallocate_pages
);
2201 if (deallocate_pages
) {
2204 for (i
= 0; i
< area
->nr_pages
; i
++) {
2205 struct page
*page
= area
->pages
[i
];
2208 __free_pages(page
, 0);
2211 kvfree(area
->pages
);
2218 static inline void __vfree_deferred(const void *addr
)
2221 * Use raw_cpu_ptr() because this can be called from preemptible
2222 * context. Preemption is absolutely fine here, because the llist_add()
2223 * implementation is lockless, so it works even if we are adding to
2224 * nother cpu's list. schedule_work() should be fine with this too.
2226 struct vfree_deferred
*p
= raw_cpu_ptr(&vfree_deferred
);
2228 if (llist_add((struct llist_node
*)addr
, &p
->list
))
2229 schedule_work(&p
->wq
);
2233 * vfree_atomic - release memory allocated by vmalloc()
2234 * @addr: memory base address
2236 * This one is just like vfree() but can be called in any atomic context
2239 void vfree_atomic(const void *addr
)
2243 kmemleak_free(addr
);
2247 __vfree_deferred(addr
);
2250 static void __vfree(const void *addr
)
2252 if (unlikely(in_interrupt()))
2253 __vfree_deferred(addr
);
2259 * vfree - release memory allocated by vmalloc()
2260 * @addr: memory base address
2262 * Free the virtually continuous memory area starting at @addr, as
2263 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
2264 * NULL, no operation is performed.
2266 * Must not be called in NMI context (strictly speaking, only if we don't
2267 * have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
2268 * conventions for vfree() arch-depenedent would be a really bad idea)
2270 * May sleep if called *not* from interrupt context.
2272 * NOTE: assumes that the object at @addr has a size >= sizeof(llist_node)
2274 void vfree(const void *addr
)
2278 kmemleak_free(addr
);
2280 might_sleep_if(!in_interrupt());
2287 EXPORT_SYMBOL(vfree
);
2290 * vunmap - release virtual mapping obtained by vmap()
2291 * @addr: memory base address
2293 * Free the virtually contiguous memory area starting at @addr,
2294 * which was created from the page array passed to vmap().
2296 * Must not be called in interrupt context.
2298 void vunmap(const void *addr
)
2300 BUG_ON(in_interrupt());
2305 EXPORT_SYMBOL(vunmap
);
2308 * vmap - map an array of pages into virtually contiguous space
2309 * @pages: array of page pointers
2310 * @count: number of pages to map
2311 * @flags: vm_area->flags
2312 * @prot: page protection for the mapping
2314 * Maps @count pages from @pages into contiguous kernel virtual
2317 * Return: the address of the area or %NULL on failure
2319 void *vmap(struct page
**pages
, unsigned int count
,
2320 unsigned long flags
, pgprot_t prot
)
2322 struct vm_struct
*area
;
2323 unsigned long size
; /* In bytes */
2327 if (count
> totalram_pages())
2330 size
= (unsigned long)count
<< PAGE_SHIFT
;
2331 area
= get_vm_area_caller(size
, flags
, __builtin_return_address(0));
2335 if (map_vm_area(area
, prot
, pages
)) {
2342 EXPORT_SYMBOL(vmap
);
2344 static void *__vmalloc_node(unsigned long size
, unsigned long align
,
2345 gfp_t gfp_mask
, pgprot_t prot
,
2346 int node
, const void *caller
);
2347 static void *__vmalloc_area_node(struct vm_struct
*area
, gfp_t gfp_mask
,
2348 pgprot_t prot
, int node
)
2350 struct page
**pages
;
2351 unsigned int nr_pages
, array_size
, i
;
2352 const gfp_t nested_gfp
= (gfp_mask
& GFP_RECLAIM_MASK
) | __GFP_ZERO
;
2353 const gfp_t alloc_mask
= gfp_mask
| __GFP_NOWARN
;
2354 const gfp_t highmem_mask
= (gfp_mask
& (GFP_DMA
| GFP_DMA32
)) ?
2358 nr_pages
= get_vm_area_size(area
) >> PAGE_SHIFT
;
2359 array_size
= (nr_pages
* sizeof(struct page
*));
2361 area
->nr_pages
= nr_pages
;
2362 /* Please note that the recursion is strictly bounded. */
2363 if (array_size
> PAGE_SIZE
) {
2364 pages
= __vmalloc_node(array_size
, 1, nested_gfp
|highmem_mask
,
2365 PAGE_KERNEL
, node
, area
->caller
);
2367 pages
= kmalloc_node(array_size
, nested_gfp
, node
);
2369 area
->pages
= pages
;
2371 remove_vm_area(area
->addr
);
2376 for (i
= 0; i
< area
->nr_pages
; i
++) {
2379 if (node
== NUMA_NO_NODE
)
2380 page
= alloc_page(alloc_mask
|highmem_mask
);
2382 page
= alloc_pages_node(node
, alloc_mask
|highmem_mask
, 0);
2384 if (unlikely(!page
)) {
2385 /* Successfully allocated i pages, free them in __vunmap() */
2389 area
->pages
[i
] = page
;
2390 if (gfpflags_allow_blocking(gfp_mask
|highmem_mask
))
2394 if (map_vm_area(area
, prot
, pages
))
2399 warn_alloc(gfp_mask
, NULL
,
2400 "vmalloc: allocation failure, allocated %ld of %ld bytes",
2401 (area
->nr_pages
*PAGE_SIZE
), area
->size
);
2402 __vfree(area
->addr
);
2407 * __vmalloc_node_range - allocate virtually contiguous memory
2408 * @size: allocation size
2409 * @align: desired alignment
2410 * @start: vm area range start
2411 * @end: vm area range end
2412 * @gfp_mask: flags for the page level allocator
2413 * @prot: protection mask for the allocated pages
2414 * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD)
2415 * @node: node to use for allocation or NUMA_NO_NODE
2416 * @caller: caller's return address
2418 * Allocate enough pages to cover @size from the page level
2419 * allocator with @gfp_mask flags. Map them into contiguous
2420 * kernel virtual space, using a pagetable protection of @prot.
2422 * Return: the address of the area or %NULL on failure
2424 void *__vmalloc_node_range(unsigned long size
, unsigned long align
,
2425 unsigned long start
, unsigned long end
, gfp_t gfp_mask
,
2426 pgprot_t prot
, unsigned long vm_flags
, int node
,
2429 struct vm_struct
*area
;
2431 unsigned long real_size
= size
;
2433 size
= PAGE_ALIGN(size
);
2434 if (!size
|| (size
>> PAGE_SHIFT
) > totalram_pages())
2437 area
= __get_vm_area_node(size
, align
, VM_ALLOC
| VM_UNINITIALIZED
|
2438 vm_flags
, start
, end
, node
, gfp_mask
, caller
);
2442 addr
= __vmalloc_area_node(area
, gfp_mask
, prot
, node
);
2447 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
2448 * flag. It means that vm_struct is not fully initialized.
2449 * Now, it is fully initialized, so remove this flag here.
2451 clear_vm_uninitialized_flag(area
);
2453 kmemleak_vmalloc(area
, size
, gfp_mask
);
2458 warn_alloc(gfp_mask
, NULL
,
2459 "vmalloc: allocation failure: %lu bytes", real_size
);
2464 * This is only for performance analysis of vmalloc and stress purpose.
2465 * It is required by vmalloc test module, therefore do not use it other
2468 #ifdef CONFIG_TEST_VMALLOC_MODULE
2469 EXPORT_SYMBOL_GPL(__vmalloc_node_range
);
2473 * __vmalloc_node - allocate virtually contiguous memory
2474 * @size: allocation size
2475 * @align: desired alignment
2476 * @gfp_mask: flags for the page level allocator
2477 * @prot: protection mask for the allocated pages
2478 * @node: node to use for allocation or NUMA_NO_NODE
2479 * @caller: caller's return address
2481 * Allocate enough pages to cover @size from the page level
2482 * allocator with @gfp_mask flags. Map them into contiguous
2483 * kernel virtual space, using a pagetable protection of @prot.
2485 * Reclaim modifiers in @gfp_mask - __GFP_NORETRY, __GFP_RETRY_MAYFAIL
2486 * and __GFP_NOFAIL are not supported
2488 * Any use of gfp flags outside of GFP_KERNEL should be consulted
2491 * Return: pointer to the allocated memory or %NULL on error
2493 static void *__vmalloc_node(unsigned long size
, unsigned long align
,
2494 gfp_t gfp_mask
, pgprot_t prot
,
2495 int node
, const void *caller
)
2497 return __vmalloc_node_range(size
, align
, VMALLOC_START
, VMALLOC_END
,
2498 gfp_mask
, prot
, 0, node
, caller
);
2501 void *__vmalloc(unsigned long size
, gfp_t gfp_mask
, pgprot_t prot
)
2503 return __vmalloc_node(size
, 1, gfp_mask
, prot
, NUMA_NO_NODE
,
2504 __builtin_return_address(0));
2506 EXPORT_SYMBOL(__vmalloc
);
2508 static inline void *__vmalloc_node_flags(unsigned long size
,
2509 int node
, gfp_t flags
)
2511 return __vmalloc_node(size
, 1, flags
, PAGE_KERNEL
,
2512 node
, __builtin_return_address(0));
2516 void *__vmalloc_node_flags_caller(unsigned long size
, int node
, gfp_t flags
,
2519 return __vmalloc_node(size
, 1, flags
, PAGE_KERNEL
, node
, caller
);
2523 * vmalloc - allocate virtually contiguous memory
2524 * @size: allocation size
2526 * Allocate enough pages to cover @size from the page level
2527 * allocator and map them into contiguous kernel virtual space.
2529 * For tight control over page level allocator and protection flags
2530 * use __vmalloc() instead.
2532 * Return: pointer to the allocated memory or %NULL on error
2534 void *vmalloc(unsigned long size
)
2536 return __vmalloc_node_flags(size
, NUMA_NO_NODE
,
2539 EXPORT_SYMBOL(vmalloc
);
2542 * vzalloc - allocate virtually contiguous memory with zero fill
2543 * @size: allocation size
2545 * Allocate enough pages to cover @size from the page level
2546 * allocator and map them into contiguous kernel virtual space.
2547 * The memory allocated is set to zero.
2549 * For tight control over page level allocator and protection flags
2550 * use __vmalloc() instead.
2552 * Return: pointer to the allocated memory or %NULL on error
2554 void *vzalloc(unsigned long size
)
2556 return __vmalloc_node_flags(size
, NUMA_NO_NODE
,
2557 GFP_KERNEL
| __GFP_ZERO
);
2559 EXPORT_SYMBOL(vzalloc
);
2562 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
2563 * @size: allocation size
2565 * The resulting memory area is zeroed so it can be mapped to userspace
2566 * without leaking data.
2568 * Return: pointer to the allocated memory or %NULL on error
2570 void *vmalloc_user(unsigned long size
)
2572 return __vmalloc_node_range(size
, SHMLBA
, VMALLOC_START
, VMALLOC_END
,
2573 GFP_KERNEL
| __GFP_ZERO
, PAGE_KERNEL
,
2574 VM_USERMAP
, NUMA_NO_NODE
,
2575 __builtin_return_address(0));
2577 EXPORT_SYMBOL(vmalloc_user
);
2580 * vmalloc_node - allocate memory on a specific node
2581 * @size: allocation size
2584 * Allocate enough pages to cover @size from the page level
2585 * allocator and map them into contiguous kernel virtual space.
2587 * For tight control over page level allocator and protection flags
2588 * use __vmalloc() instead.
2590 * Return: pointer to the allocated memory or %NULL on error
2592 void *vmalloc_node(unsigned long size
, int node
)
2594 return __vmalloc_node(size
, 1, GFP_KERNEL
, PAGE_KERNEL
,
2595 node
, __builtin_return_address(0));
2597 EXPORT_SYMBOL(vmalloc_node
);
2600 * vzalloc_node - allocate memory on a specific node with zero fill
2601 * @size: allocation size
2604 * Allocate enough pages to cover @size from the page level
2605 * allocator and map them into contiguous kernel virtual space.
2606 * The memory allocated is set to zero.
2608 * For tight control over page level allocator and protection flags
2609 * use __vmalloc_node() instead.
2611 * Return: pointer to the allocated memory or %NULL on error
2613 void *vzalloc_node(unsigned long size
, int node
)
2615 return __vmalloc_node_flags(size
, node
,
2616 GFP_KERNEL
| __GFP_ZERO
);
2618 EXPORT_SYMBOL(vzalloc_node
);
2621 * vmalloc_exec - allocate virtually contiguous, executable memory
2622 * @size: allocation size
2624 * Kernel-internal function to allocate enough pages to cover @size
2625 * the page level allocator and map them into contiguous and
2626 * executable kernel virtual space.
2628 * For tight control over page level allocator and protection flags
2629 * use __vmalloc() instead.
2631 * Return: pointer to the allocated memory or %NULL on error
2633 void *vmalloc_exec(unsigned long size
)
2635 return __vmalloc_node_range(size
, 1, VMALLOC_START
, VMALLOC_END
,
2636 GFP_KERNEL
, PAGE_KERNEL_EXEC
, VM_FLUSH_RESET_PERMS
,
2637 NUMA_NO_NODE
, __builtin_return_address(0));
2640 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
2641 #define GFP_VMALLOC32 (GFP_DMA32 | GFP_KERNEL)
2642 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
2643 #define GFP_VMALLOC32 (GFP_DMA | GFP_KERNEL)
2646 * 64b systems should always have either DMA or DMA32 zones. For others
2647 * GFP_DMA32 should do the right thing and use the normal zone.
2649 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
2653 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
2654 * @size: allocation size
2656 * Allocate enough 32bit PA addressable pages to cover @size from the
2657 * page level allocator and map them into contiguous kernel virtual space.
2659 * Return: pointer to the allocated memory or %NULL on error
2661 void *vmalloc_32(unsigned long size
)
2663 return __vmalloc_node(size
, 1, GFP_VMALLOC32
, PAGE_KERNEL
,
2664 NUMA_NO_NODE
, __builtin_return_address(0));
2666 EXPORT_SYMBOL(vmalloc_32
);
2669 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
2670 * @size: allocation size
2672 * The resulting memory area is 32bit addressable and zeroed so it can be
2673 * mapped to userspace without leaking data.
2675 * Return: pointer to the allocated memory or %NULL on error
2677 void *vmalloc_32_user(unsigned long size
)
2679 return __vmalloc_node_range(size
, SHMLBA
, VMALLOC_START
, VMALLOC_END
,
2680 GFP_VMALLOC32
| __GFP_ZERO
, PAGE_KERNEL
,
2681 VM_USERMAP
, NUMA_NO_NODE
,
2682 __builtin_return_address(0));
2684 EXPORT_SYMBOL(vmalloc_32_user
);
2687 * small helper routine , copy contents to buf from addr.
2688 * If the page is not present, fill zero.
2691 static int aligned_vread(char *buf
, char *addr
, unsigned long count
)
2697 unsigned long offset
, length
;
2699 offset
= offset_in_page(addr
);
2700 length
= PAGE_SIZE
- offset
;
2703 p
= vmalloc_to_page(addr
);
2705 * To do safe access to this _mapped_ area, we need
2706 * lock. But adding lock here means that we need to add
2707 * overhead of vmalloc()/vfree() calles for this _debug_
2708 * interface, rarely used. Instead of that, we'll use
2709 * kmap() and get small overhead in this access function.
2713 * we can expect USER0 is not used (see vread/vwrite's
2714 * function description)
2716 void *map
= kmap_atomic(p
);
2717 memcpy(buf
, map
+ offset
, length
);
2720 memset(buf
, 0, length
);
2730 static int aligned_vwrite(char *buf
, char *addr
, unsigned long count
)
2736 unsigned long offset
, length
;
2738 offset
= offset_in_page(addr
);
2739 length
= PAGE_SIZE
- offset
;
2742 p
= vmalloc_to_page(addr
);
2744 * To do safe access to this _mapped_ area, we need
2745 * lock. But adding lock here means that we need to add
2746 * overhead of vmalloc()/vfree() calles for this _debug_
2747 * interface, rarely used. Instead of that, we'll use
2748 * kmap() and get small overhead in this access function.
2752 * we can expect USER0 is not used (see vread/vwrite's
2753 * function description)
2755 void *map
= kmap_atomic(p
);
2756 memcpy(map
+ offset
, buf
, length
);
2768 * vread() - read vmalloc area in a safe way.
2769 * @buf: buffer for reading data
2770 * @addr: vm address.
2771 * @count: number of bytes to be read.
2773 * This function checks that addr is a valid vmalloc'ed area, and
2774 * copy data from that area to a given buffer. If the given memory range
2775 * of [addr...addr+count) includes some valid address, data is copied to
2776 * proper area of @buf. If there are memory holes, they'll be zero-filled.
2777 * IOREMAP area is treated as memory hole and no copy is done.
2779 * If [addr...addr+count) doesn't includes any intersects with alive
2780 * vm_struct area, returns 0. @buf should be kernel's buffer.
2782 * Note: In usual ops, vread() is never necessary because the caller
2783 * should know vmalloc() area is valid and can use memcpy().
2784 * This is for routines which have to access vmalloc area without
2785 * any informaion, as /dev/kmem.
2787 * Return: number of bytes for which addr and buf should be increased
2788 * (same number as @count) or %0 if [addr...addr+count) doesn't
2789 * include any intersection with valid vmalloc area
2791 long vread(char *buf
, char *addr
, unsigned long count
)
2793 struct vmap_area
*va
;
2794 struct vm_struct
*vm
;
2795 char *vaddr
, *buf_start
= buf
;
2796 unsigned long buflen
= count
;
2799 /* Don't allow overflow */
2800 if ((unsigned long) addr
+ count
< count
)
2801 count
= -(unsigned long) addr
;
2803 spin_lock(&vmap_area_lock
);
2804 list_for_each_entry(va
, &vmap_area_list
, list
) {
2808 if (!(va
->flags
& VM_VM_AREA
))
2812 vaddr
= (char *) vm
->addr
;
2813 if (addr
>= vaddr
+ get_vm_area_size(vm
))
2815 while (addr
< vaddr
) {
2823 n
= vaddr
+ get_vm_area_size(vm
) - addr
;
2826 if (!(vm
->flags
& VM_IOREMAP
))
2827 aligned_vread(buf
, addr
, n
);
2828 else /* IOREMAP area is treated as memory hole */
2835 spin_unlock(&vmap_area_lock
);
2837 if (buf
== buf_start
)
2839 /* zero-fill memory holes */
2840 if (buf
!= buf_start
+ buflen
)
2841 memset(buf
, 0, buflen
- (buf
- buf_start
));
2847 * vwrite() - write vmalloc area in a safe way.
2848 * @buf: buffer for source data
2849 * @addr: vm address.
2850 * @count: number of bytes to be read.
2852 * This function checks that addr is a valid vmalloc'ed area, and
2853 * copy data from a buffer to the given addr. If specified range of
2854 * [addr...addr+count) includes some valid address, data is copied from
2855 * proper area of @buf. If there are memory holes, no copy to hole.
2856 * IOREMAP area is treated as memory hole and no copy is done.
2858 * If [addr...addr+count) doesn't includes any intersects with alive
2859 * vm_struct area, returns 0. @buf should be kernel's buffer.
2861 * Note: In usual ops, vwrite() is never necessary because the caller
2862 * should know vmalloc() area is valid and can use memcpy().
2863 * This is for routines which have to access vmalloc area without
2864 * any informaion, as /dev/kmem.
2866 * Return: number of bytes for which addr and buf should be
2867 * increased (same number as @count) or %0 if [addr...addr+count)
2868 * doesn't include any intersection with valid vmalloc area
2870 long vwrite(char *buf
, char *addr
, unsigned long count
)
2872 struct vmap_area
*va
;
2873 struct vm_struct
*vm
;
2875 unsigned long n
, buflen
;
2878 /* Don't allow overflow */
2879 if ((unsigned long) addr
+ count
< count
)
2880 count
= -(unsigned long) addr
;
2883 spin_lock(&vmap_area_lock
);
2884 list_for_each_entry(va
, &vmap_area_list
, list
) {
2888 if (!(va
->flags
& VM_VM_AREA
))
2892 vaddr
= (char *) vm
->addr
;
2893 if (addr
>= vaddr
+ get_vm_area_size(vm
))
2895 while (addr
< vaddr
) {
2902 n
= vaddr
+ get_vm_area_size(vm
) - addr
;
2905 if (!(vm
->flags
& VM_IOREMAP
)) {
2906 aligned_vwrite(buf
, addr
, n
);
2914 spin_unlock(&vmap_area_lock
);
2921 * remap_vmalloc_range_partial - map vmalloc pages to userspace
2922 * @vma: vma to cover
2923 * @uaddr: target user address to start at
2924 * @kaddr: virtual address of vmalloc kernel memory
2925 * @size: size of map area
2927 * Returns: 0 for success, -Exxx on failure
2929 * This function checks that @kaddr is a valid vmalloc'ed area,
2930 * and that it is big enough to cover the range starting at
2931 * @uaddr in @vma. Will return failure if that criteria isn't
2934 * Similar to remap_pfn_range() (see mm/memory.c)
2936 int remap_vmalloc_range_partial(struct vm_area_struct
*vma
, unsigned long uaddr
,
2937 void *kaddr
, unsigned long size
)
2939 struct vm_struct
*area
;
2941 size
= PAGE_ALIGN(size
);
2943 if (!PAGE_ALIGNED(uaddr
) || !PAGE_ALIGNED(kaddr
))
2946 area
= find_vm_area(kaddr
);
2950 if (!(area
->flags
& VM_USERMAP
))
2953 if (kaddr
+ size
> area
->addr
+ get_vm_area_size(area
))
2957 struct page
*page
= vmalloc_to_page(kaddr
);
2960 ret
= vm_insert_page(vma
, uaddr
, page
);
2969 vma
->vm_flags
|= VM_DONTEXPAND
| VM_DONTDUMP
;
2973 EXPORT_SYMBOL(remap_vmalloc_range_partial
);
2976 * remap_vmalloc_range - map vmalloc pages to userspace
2977 * @vma: vma to cover (map full range of vma)
2978 * @addr: vmalloc memory
2979 * @pgoff: number of pages into addr before first page to map
2981 * Returns: 0 for success, -Exxx on failure
2983 * This function checks that addr is a valid vmalloc'ed area, and
2984 * that it is big enough to cover the vma. Will return failure if
2985 * that criteria isn't met.
2987 * Similar to remap_pfn_range() (see mm/memory.c)
2989 int remap_vmalloc_range(struct vm_area_struct
*vma
, void *addr
,
2990 unsigned long pgoff
)
2992 return remap_vmalloc_range_partial(vma
, vma
->vm_start
,
2993 addr
+ (pgoff
<< PAGE_SHIFT
),
2994 vma
->vm_end
- vma
->vm_start
);
2996 EXPORT_SYMBOL(remap_vmalloc_range
);
2999 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
3002 void __weak
vmalloc_sync_all(void)
3007 static int f(pte_t
*pte
, pgtable_t table
, unsigned long addr
, void *data
)
3019 * alloc_vm_area - allocate a range of kernel address space
3020 * @size: size of the area
3021 * @ptes: returns the PTEs for the address space
3023 * Returns: NULL on failure, vm_struct on success
3025 * This function reserves a range of kernel address space, and
3026 * allocates pagetables to map that range. No actual mappings
3029 * If @ptes is non-NULL, pointers to the PTEs (in init_mm)
3030 * allocated for the VM area are returned.
3032 struct vm_struct
*alloc_vm_area(size_t size
, pte_t
**ptes
)
3034 struct vm_struct
*area
;
3036 area
= get_vm_area_caller(size
, VM_IOREMAP
,
3037 __builtin_return_address(0));
3042 * This ensures that page tables are constructed for this region
3043 * of kernel virtual address space and mapped into init_mm.
3045 if (apply_to_page_range(&init_mm
, (unsigned long)area
->addr
,
3046 size
, f
, ptes
? &ptes
: NULL
)) {
3053 EXPORT_SYMBOL_GPL(alloc_vm_area
);
3055 void free_vm_area(struct vm_struct
*area
)
3057 struct vm_struct
*ret
;
3058 ret
= remove_vm_area(area
->addr
);
3059 BUG_ON(ret
!= area
);
3062 EXPORT_SYMBOL_GPL(free_vm_area
);
3065 static struct vmap_area
*node_to_va(struct rb_node
*n
)
3067 return rb_entry_safe(n
, struct vmap_area
, rb_node
);
3071 * pvm_find_va_enclose_addr - find the vmap_area @addr belongs to
3072 * @addr: target address
3074 * Returns: vmap_area if it is found. If there is no such area
3075 * the first highest(reverse order) vmap_area is returned
3076 * i.e. va->va_start < addr && va->va_end < addr or NULL
3077 * if there are no any areas before @addr.
3079 static struct vmap_area
*
3080 pvm_find_va_enclose_addr(unsigned long addr
)
3082 struct vmap_area
*va
, *tmp
;
3085 n
= free_vmap_area_root
.rb_node
;
3089 tmp
= rb_entry(n
, struct vmap_area
, rb_node
);
3090 if (tmp
->va_start
<= addr
) {
3092 if (tmp
->va_end
>= addr
)
3105 * pvm_determine_end_from_reverse - find the highest aligned address
3106 * of free block below VMALLOC_END
3108 * in - the VA we start the search(reverse order);
3109 * out - the VA with the highest aligned end address.
3111 * Returns: determined end address within vmap_area
3113 static unsigned long
3114 pvm_determine_end_from_reverse(struct vmap_area
**va
, unsigned long align
)
3116 unsigned long vmalloc_end
= VMALLOC_END
& ~(align
- 1);
3120 list_for_each_entry_from_reverse((*va
),
3121 &free_vmap_area_list
, list
) {
3122 addr
= min((*va
)->va_end
& ~(align
- 1), vmalloc_end
);
3123 if ((*va
)->va_start
< addr
)
3132 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
3133 * @offsets: array containing offset of each area
3134 * @sizes: array containing size of each area
3135 * @nr_vms: the number of areas to allocate
3136 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
3138 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
3139 * vm_structs on success, %NULL on failure
3141 * Percpu allocator wants to use congruent vm areas so that it can
3142 * maintain the offsets among percpu areas. This function allocates
3143 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
3144 * be scattered pretty far, distance between two areas easily going up
3145 * to gigabytes. To avoid interacting with regular vmallocs, these
3146 * areas are allocated from top.
3148 * Despite its complicated look, this allocator is rather simple. It
3149 * does everything top-down and scans free blocks from the end looking
3150 * for matching base. While scanning, if any of the areas do not fit the
3151 * base address is pulled down to fit the area. Scanning is repeated till
3152 * all the areas fit and then all necessary data structures are inserted
3153 * and the result is returned.
3155 struct vm_struct
**pcpu_get_vm_areas(const unsigned long *offsets
,
3156 const size_t *sizes
, int nr_vms
,
3159 const unsigned long vmalloc_start
= ALIGN(VMALLOC_START
, align
);
3160 const unsigned long vmalloc_end
= VMALLOC_END
& ~(align
- 1);
3161 struct vmap_area
**vas
, *va
;
3162 struct vm_struct
**vms
;
3163 int area
, area2
, last_area
, term_area
;
3164 unsigned long base
, start
, size
, end
, last_end
;
3165 bool purged
= false;
3168 /* verify parameters and allocate data structures */
3169 BUG_ON(offset_in_page(align
) || !is_power_of_2(align
));
3170 for (last_area
= 0, area
= 0; area
< nr_vms
; area
++) {
3171 start
= offsets
[area
];
3172 end
= start
+ sizes
[area
];
3174 /* is everything aligned properly? */
3175 BUG_ON(!IS_ALIGNED(offsets
[area
], align
));
3176 BUG_ON(!IS_ALIGNED(sizes
[area
], align
));
3178 /* detect the area with the highest address */
3179 if (start
> offsets
[last_area
])
3182 for (area2
= area
+ 1; area2
< nr_vms
; area2
++) {
3183 unsigned long start2
= offsets
[area2
];
3184 unsigned long end2
= start2
+ sizes
[area2
];
3186 BUG_ON(start2
< end
&& start
< end2
);
3189 last_end
= offsets
[last_area
] + sizes
[last_area
];
3191 if (vmalloc_end
- vmalloc_start
< last_end
) {
3196 vms
= kcalloc(nr_vms
, sizeof(vms
[0]), GFP_KERNEL
);
3197 vas
= kcalloc(nr_vms
, sizeof(vas
[0]), GFP_KERNEL
);
3201 for (area
= 0; area
< nr_vms
; area
++) {
3202 vas
[area
] = kmem_cache_zalloc(vmap_area_cachep
, GFP_KERNEL
);
3203 vms
[area
] = kzalloc(sizeof(struct vm_struct
), GFP_KERNEL
);
3204 if (!vas
[area
] || !vms
[area
])
3208 spin_lock(&vmap_area_lock
);
3210 /* start scanning - we scan from the top, begin with the last area */
3211 area
= term_area
= last_area
;
3212 start
= offsets
[area
];
3213 end
= start
+ sizes
[area
];
3215 va
= pvm_find_va_enclose_addr(vmalloc_end
);
3216 base
= pvm_determine_end_from_reverse(&va
, align
) - end
;
3220 * base might have underflowed, add last_end before
3223 if (base
+ last_end
< vmalloc_start
+ last_end
)
3227 * Fitting base has not been found.
3233 * If this VA does not fit, move base downwards and recheck.
3235 if (base
+ start
< va
->va_start
|| base
+ end
> va
->va_end
) {
3236 va
= node_to_va(rb_prev(&va
->rb_node
));
3237 base
= pvm_determine_end_from_reverse(&va
, align
) - end
;
3243 * This area fits, move on to the previous one. If
3244 * the previous one is the terminal one, we're done.
3246 area
= (area
+ nr_vms
- 1) % nr_vms
;
3247 if (area
== term_area
)
3250 start
= offsets
[area
];
3251 end
= start
+ sizes
[area
];
3252 va
= pvm_find_va_enclose_addr(base
+ end
);
3255 /* we've found a fitting base, insert all va's */
3256 for (area
= 0; area
< nr_vms
; area
++) {
3259 start
= base
+ offsets
[area
];
3262 va
= pvm_find_va_enclose_addr(start
);
3263 if (WARN_ON_ONCE(va
== NULL
))
3264 /* It is a BUG(), but trigger recovery instead. */
3267 type
= classify_va_fit_type(va
, start
, size
);
3268 if (WARN_ON_ONCE(type
== NOTHING_FIT
))
3269 /* It is a BUG(), but trigger recovery instead. */
3272 ret
= adjust_va_to_fit_type(va
, start
, size
, type
);
3276 /* Allocated area. */
3278 va
->va_start
= start
;
3279 va
->va_end
= start
+ size
;
3281 insert_vmap_area(va
, &vmap_area_root
, &vmap_area_list
);
3284 spin_unlock(&vmap_area_lock
);
3286 /* insert all vm's */
3287 for (area
= 0; area
< nr_vms
; area
++)
3288 setup_vmalloc_vm(vms
[area
], vas
[area
], VM_ALLOC
,
3295 /* Remove previously inserted areas. */
3297 __free_vmap_area(vas
[area
]);
3302 spin_unlock(&vmap_area_lock
);
3304 purge_vmap_area_lazy();
3307 /* Before "retry", check if we recover. */
3308 for (area
= 0; area
< nr_vms
; area
++) {
3312 vas
[area
] = kmem_cache_zalloc(
3313 vmap_area_cachep
, GFP_KERNEL
);
3322 for (area
= 0; area
< nr_vms
; area
++) {
3324 kmem_cache_free(vmap_area_cachep
, vas
[area
]);
3335 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
3336 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
3337 * @nr_vms: the number of allocated areas
3339 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
3341 void pcpu_free_vm_areas(struct vm_struct
**vms
, int nr_vms
)
3345 for (i
= 0; i
< nr_vms
; i
++)
3346 free_vm_area(vms
[i
]);
3349 #endif /* CONFIG_SMP */
3351 #ifdef CONFIG_PROC_FS
3352 static void *s_start(struct seq_file
*m
, loff_t
*pos
)
3353 __acquires(&vmap_area_lock
)
3355 spin_lock(&vmap_area_lock
);
3356 return seq_list_start(&vmap_area_list
, *pos
);
3359 static void *s_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
3361 return seq_list_next(p
, &vmap_area_list
, pos
);
3364 static void s_stop(struct seq_file
*m
, void *p
)
3365 __releases(&vmap_area_lock
)
3367 spin_unlock(&vmap_area_lock
);
3370 static void show_numa_info(struct seq_file
*m
, struct vm_struct
*v
)
3372 if (IS_ENABLED(CONFIG_NUMA
)) {
3373 unsigned int nr
, *counters
= m
->private;
3378 if (v
->flags
& VM_UNINITIALIZED
)
3380 /* Pair with smp_wmb() in clear_vm_uninitialized_flag() */
3383 memset(counters
, 0, nr_node_ids
* sizeof(unsigned int));
3385 for (nr
= 0; nr
< v
->nr_pages
; nr
++)
3386 counters
[page_to_nid(v
->pages
[nr
])]++;
3388 for_each_node_state(nr
, N_HIGH_MEMORY
)
3390 seq_printf(m
, " N%u=%u", nr
, counters
[nr
]);
3394 static int s_show(struct seq_file
*m
, void *p
)
3396 struct vmap_area
*va
;
3397 struct vm_struct
*v
;
3399 va
= list_entry(p
, struct vmap_area
, list
);
3402 * s_show can encounter race with remove_vm_area, !VM_VM_AREA on
3403 * behalf of vmap area is being tear down or vm_map_ram allocation.
3405 if (!(va
->flags
& VM_VM_AREA
)) {
3406 seq_printf(m
, "0x%pK-0x%pK %7ld %s\n",
3407 (void *)va
->va_start
, (void *)va
->va_end
,
3408 va
->va_end
- va
->va_start
,
3409 va
->flags
& VM_LAZY_FREE
? "unpurged vm_area" : "vm_map_ram");
3416 seq_printf(m
, "0x%pK-0x%pK %7ld",
3417 v
->addr
, v
->addr
+ v
->size
, v
->size
);
3420 seq_printf(m
, " %pS", v
->caller
);
3423 seq_printf(m
, " pages=%d", v
->nr_pages
);
3426 seq_printf(m
, " phys=%pa", &v
->phys_addr
);
3428 if (v
->flags
& VM_IOREMAP
)
3429 seq_puts(m
, " ioremap");
3431 if (v
->flags
& VM_ALLOC
)
3432 seq_puts(m
, " vmalloc");
3434 if (v
->flags
& VM_MAP
)
3435 seq_puts(m
, " vmap");
3437 if (v
->flags
& VM_USERMAP
)
3438 seq_puts(m
, " user");
3440 if (is_vmalloc_addr(v
->pages
))
3441 seq_puts(m
, " vpages");
3443 show_numa_info(m
, v
);
3448 static const struct seq_operations vmalloc_op
= {
3455 static int __init
proc_vmalloc_init(void)
3457 if (IS_ENABLED(CONFIG_NUMA
))
3458 proc_create_seq_private("vmallocinfo", 0400, NULL
,
3460 nr_node_ids
* sizeof(unsigned int), NULL
);
3462 proc_create_seq("vmallocinfo", 0400, NULL
, &vmalloc_op
);
3465 module_init(proc_vmalloc_init
);