4 * Copyright (C) 1993 Linus Torvalds
5 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
6 * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
7 * Major rework to support vmap/vunmap, Christoph Hellwig, SGI, August 2002
8 * Numa awareness, Christoph Lameter, SGI, June 2005
11 #include <linux/vmalloc.h>
13 #include <linux/module.h>
14 #include <linux/highmem.h>
15 #include <linux/sched.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/interrupt.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <linux/debugobjects.h>
22 #include <linux/kallsyms.h>
23 #include <linux/list.h>
24 #include <linux/rbtree.h>
25 #include <linux/radix-tree.h>
26 #include <linux/rcupdate.h>
27 #include <linux/pfn.h>
28 #include <linux/kmemleak.h>
29 #include <asm/atomic.h>
30 #include <asm/uaccess.h>
31 #include <asm/tlbflush.h>
32 #include <asm/shmparam.h>
34 /*** Page table manipulation functions ***/
36 static void vunmap_pte_range(pmd_t
*pmd
, unsigned long addr
, unsigned long end
)
40 pte
= pte_offset_kernel(pmd
, addr
);
42 pte_t ptent
= ptep_get_and_clear(&init_mm
, addr
, pte
);
43 WARN_ON(!pte_none(ptent
) && !pte_present(ptent
));
44 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
47 static void vunmap_pmd_range(pud_t
*pud
, unsigned long addr
, unsigned long end
)
52 pmd
= pmd_offset(pud
, addr
);
54 next
= pmd_addr_end(addr
, end
);
55 if (pmd_none_or_clear_bad(pmd
))
57 vunmap_pte_range(pmd
, addr
, next
);
58 } while (pmd
++, addr
= next
, addr
!= end
);
61 static void vunmap_pud_range(pgd_t
*pgd
, unsigned long addr
, unsigned long end
)
66 pud
= pud_offset(pgd
, addr
);
68 next
= pud_addr_end(addr
, end
);
69 if (pud_none_or_clear_bad(pud
))
71 vunmap_pmd_range(pud
, addr
, next
);
72 } while (pud
++, addr
= next
, addr
!= end
);
75 static void vunmap_page_range(unsigned long addr
, unsigned long end
)
81 pgd
= pgd_offset_k(addr
);
83 next
= pgd_addr_end(addr
, end
);
84 if (pgd_none_or_clear_bad(pgd
))
86 vunmap_pud_range(pgd
, addr
, next
);
87 } while (pgd
++, addr
= next
, addr
!= end
);
90 static int vmap_pte_range(pmd_t
*pmd
, unsigned long addr
,
91 unsigned long end
, pgprot_t prot
, struct page
**pages
, int *nr
)
96 * nr is a running index into the array which helps higher level
97 * callers keep track of where we're up to.
100 pte
= pte_alloc_kernel(pmd
, addr
);
104 struct page
*page
= pages
[*nr
];
106 if (WARN_ON(!pte_none(*pte
)))
110 set_pte_at(&init_mm
, addr
, pte
, mk_pte(page
, prot
));
112 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
116 static int vmap_pmd_range(pud_t
*pud
, unsigned long addr
,
117 unsigned long end
, pgprot_t prot
, struct page
**pages
, int *nr
)
122 pmd
= pmd_alloc(&init_mm
, pud
, addr
);
126 next
= pmd_addr_end(addr
, end
);
127 if (vmap_pte_range(pmd
, addr
, next
, prot
, pages
, nr
))
129 } while (pmd
++, addr
= next
, addr
!= end
);
133 static int vmap_pud_range(pgd_t
*pgd
, unsigned long addr
,
134 unsigned long end
, pgprot_t prot
, struct page
**pages
, int *nr
)
139 pud
= pud_alloc(&init_mm
, pgd
, addr
);
143 next
= pud_addr_end(addr
, end
);
144 if (vmap_pmd_range(pud
, addr
, next
, prot
, pages
, nr
))
146 } while (pud
++, addr
= next
, addr
!= end
);
151 * Set up page tables in kva (addr, end). The ptes shall have prot "prot", and
152 * will have pfns corresponding to the "pages" array.
154 * Ie. pte at addr+N*PAGE_SIZE shall point to pfn corresponding to pages[N]
156 static int vmap_page_range_noflush(unsigned long start
, unsigned long end
,
157 pgprot_t prot
, struct page
**pages
)
161 unsigned long addr
= start
;
166 pgd
= pgd_offset_k(addr
);
168 next
= pgd_addr_end(addr
, end
);
169 err
= vmap_pud_range(pgd
, addr
, next
, prot
, pages
, &nr
);
172 } while (pgd
++, addr
= next
, addr
!= end
);
177 static int vmap_page_range(unsigned long start
, unsigned long end
,
178 pgprot_t prot
, struct page
**pages
)
182 ret
= vmap_page_range_noflush(start
, end
, prot
, pages
);
183 flush_cache_vmap(start
, end
);
187 int is_vmalloc_or_module_addr(const void *x
)
190 * ARM, x86-64 and sparc64 put modules in a special place,
191 * and fall back on vmalloc() if that fails. Others
192 * just put it in the vmalloc space.
194 #if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
195 unsigned long addr
= (unsigned long)x
;
196 if (addr
>= MODULES_VADDR
&& addr
< MODULES_END
)
199 return is_vmalloc_addr(x
);
203 * Walk a vmap address to the struct page it maps.
205 struct page
*vmalloc_to_page(const void *vmalloc_addr
)
207 unsigned long addr
= (unsigned long) vmalloc_addr
;
208 struct page
*page
= NULL
;
209 pgd_t
*pgd
= pgd_offset_k(addr
);
212 * XXX we might need to change this if we add VIRTUAL_BUG_ON for
213 * architectures that do not vmalloc module space
215 VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr
));
217 if (!pgd_none(*pgd
)) {
218 pud_t
*pud
= pud_offset(pgd
, addr
);
219 if (!pud_none(*pud
)) {
220 pmd_t
*pmd
= pmd_offset(pud
, addr
);
221 if (!pmd_none(*pmd
)) {
224 ptep
= pte_offset_map(pmd
, addr
);
226 if (pte_present(pte
))
227 page
= pte_page(pte
);
234 EXPORT_SYMBOL(vmalloc_to_page
);
237 * Map a vmalloc()-space virtual address to the physical page frame number.
239 unsigned long vmalloc_to_pfn(const void *vmalloc_addr
)
241 return page_to_pfn(vmalloc_to_page(vmalloc_addr
));
243 EXPORT_SYMBOL(vmalloc_to_pfn
);
246 /*** Global kva allocator ***/
248 #define VM_LAZY_FREE 0x01
249 #define VM_LAZY_FREEING 0x02
250 #define VM_VM_AREA 0x04
253 unsigned long va_start
;
254 unsigned long va_end
;
256 struct rb_node rb_node
; /* address sorted rbtree */
257 struct list_head list
; /* address sorted list */
258 struct list_head purge_list
; /* "lazy purge" list */
260 struct rcu_head rcu_head
;
263 static DEFINE_SPINLOCK(vmap_area_lock
);
264 static struct rb_root vmap_area_root
= RB_ROOT
;
265 static LIST_HEAD(vmap_area_list
);
266 static unsigned long vmap_area_pcpu_hole
;
268 static struct vmap_area
*__find_vmap_area(unsigned long addr
)
270 struct rb_node
*n
= vmap_area_root
.rb_node
;
273 struct vmap_area
*va
;
275 va
= rb_entry(n
, struct vmap_area
, rb_node
);
276 if (addr
< va
->va_start
)
278 else if (addr
> va
->va_start
)
287 static void __insert_vmap_area(struct vmap_area
*va
)
289 struct rb_node
**p
= &vmap_area_root
.rb_node
;
290 struct rb_node
*parent
= NULL
;
294 struct vmap_area
*tmp_va
;
297 tmp_va
= rb_entry(parent
, struct vmap_area
, rb_node
);
298 if (va
->va_start
< tmp_va
->va_end
)
300 else if (va
->va_end
> tmp_va
->va_start
)
306 rb_link_node(&va
->rb_node
, parent
, p
);
307 rb_insert_color(&va
->rb_node
, &vmap_area_root
);
309 /* address-sort this list so it is usable like the vmlist */
310 tmp
= rb_prev(&va
->rb_node
);
312 struct vmap_area
*prev
;
313 prev
= rb_entry(tmp
, struct vmap_area
, rb_node
);
314 list_add_rcu(&va
->list
, &prev
->list
);
316 list_add_rcu(&va
->list
, &vmap_area_list
);
319 static void purge_vmap_area_lazy(void);
322 * Allocate a region of KVA of the specified size and alignment, within the
325 static struct vmap_area
*alloc_vmap_area(unsigned long size
,
327 unsigned long vstart
, unsigned long vend
,
328 int node
, gfp_t gfp_mask
)
330 struct vmap_area
*va
;
336 BUG_ON(size
& ~PAGE_MASK
);
338 va
= kmalloc_node(sizeof(struct vmap_area
),
339 gfp_mask
& GFP_RECLAIM_MASK
, node
);
341 return ERR_PTR(-ENOMEM
);
344 addr
= ALIGN(vstart
, align
);
346 spin_lock(&vmap_area_lock
);
347 if (addr
+ size
- 1 < addr
)
350 /* XXX: could have a last_hole cache */
351 n
= vmap_area_root
.rb_node
;
353 struct vmap_area
*first
= NULL
;
356 struct vmap_area
*tmp
;
357 tmp
= rb_entry(n
, struct vmap_area
, rb_node
);
358 if (tmp
->va_end
>= addr
) {
359 if (!first
&& tmp
->va_start
< addr
+ size
)
371 if (first
->va_end
< addr
) {
372 n
= rb_next(&first
->rb_node
);
374 first
= rb_entry(n
, struct vmap_area
, rb_node
);
379 while (addr
+ size
> first
->va_start
&& addr
+ size
<= vend
) {
380 addr
= ALIGN(first
->va_end
+ PAGE_SIZE
, align
);
381 if (addr
+ size
- 1 < addr
)
384 n
= rb_next(&first
->rb_node
);
386 first
= rb_entry(n
, struct vmap_area
, rb_node
);
392 if (addr
+ size
> vend
) {
394 spin_unlock(&vmap_area_lock
);
396 purge_vmap_area_lazy();
400 if (printk_ratelimit())
402 "vmap allocation for size %lu failed: "
403 "use vmalloc=<size> to increase size.\n", size
);
405 return ERR_PTR(-EBUSY
);
408 BUG_ON(addr
& (align
-1));
411 va
->va_end
= addr
+ size
;
413 __insert_vmap_area(va
);
414 spin_unlock(&vmap_area_lock
);
419 static void rcu_free_va(struct rcu_head
*head
)
421 struct vmap_area
*va
= container_of(head
, struct vmap_area
, rcu_head
);
426 static void __free_vmap_area(struct vmap_area
*va
)
428 BUG_ON(RB_EMPTY_NODE(&va
->rb_node
));
429 rb_erase(&va
->rb_node
, &vmap_area_root
);
430 RB_CLEAR_NODE(&va
->rb_node
);
431 list_del_rcu(&va
->list
);
434 * Track the highest possible candidate for pcpu area
435 * allocation. Areas outside of vmalloc area can be returned
436 * here too, consider only end addresses which fall inside
437 * vmalloc area proper.
439 if (va
->va_end
> VMALLOC_START
&& va
->va_end
<= VMALLOC_END
)
440 vmap_area_pcpu_hole
= max(vmap_area_pcpu_hole
, va
->va_end
);
442 call_rcu(&va
->rcu_head
, rcu_free_va
);
446 * Free a region of KVA allocated by alloc_vmap_area
448 static void free_vmap_area(struct vmap_area
*va
)
450 spin_lock(&vmap_area_lock
);
451 __free_vmap_area(va
);
452 spin_unlock(&vmap_area_lock
);
456 * Clear the pagetable entries of a given vmap_area
458 static void unmap_vmap_area(struct vmap_area
*va
)
460 vunmap_page_range(va
->va_start
, va
->va_end
);
463 static void vmap_debug_free_range(unsigned long start
, unsigned long end
)
466 * Unmap page tables and force a TLB flush immediately if
467 * CONFIG_DEBUG_PAGEALLOC is set. This catches use after free
468 * bugs similarly to those in linear kernel virtual address
469 * space after a page has been freed.
471 * All the lazy freeing logic is still retained, in order to
472 * minimise intrusiveness of this debugging feature.
474 * This is going to be *slow* (linear kernel virtual address
475 * debugging doesn't do a broadcast TLB flush so it is a lot
478 #ifdef CONFIG_DEBUG_PAGEALLOC
479 vunmap_page_range(start
, end
);
480 flush_tlb_kernel_range(start
, end
);
485 * lazy_max_pages is the maximum amount of virtual address space we gather up
486 * before attempting to purge with a TLB flush.
488 * There is a tradeoff here: a larger number will cover more kernel page tables
489 * and take slightly longer to purge, but it will linearly reduce the number of
490 * global TLB flushes that must be performed. It would seem natural to scale
491 * this number up linearly with the number of CPUs (because vmapping activity
492 * could also scale linearly with the number of CPUs), however it is likely
493 * that in practice, workloads might be constrained in other ways that mean
494 * vmap activity will not scale linearly with CPUs. Also, I want to be
495 * conservative and not introduce a big latency on huge systems, so go with
496 * a less aggressive log scale. It will still be an improvement over the old
497 * code, and it will be simple to change the scale factor if we find that it
498 * becomes a problem on bigger systems.
500 static unsigned long lazy_max_pages(void)
504 log
= fls(num_online_cpus());
506 return log
* (32UL * 1024 * 1024 / PAGE_SIZE
);
509 static atomic_t vmap_lazy_nr
= ATOMIC_INIT(0);
511 /* for per-CPU blocks */
512 static void purge_fragmented_blocks_allcpus(void);
515 * called before a call to iounmap() if the caller wants vm_area_struct's
518 void set_iounmap_nonlazy(void)
520 atomic_set(&vmap_lazy_nr
, lazy_max_pages()+1);
524 * Purges all lazily-freed vmap areas.
526 * If sync is 0 then don't purge if there is already a purge in progress.
527 * If force_flush is 1, then flush kernel TLBs between *start and *end even
528 * if we found no lazy vmap areas to unmap (callers can use this to optimise
529 * their own TLB flushing).
530 * Returns with *start = min(*start, lowest purged address)
531 * *end = max(*end, highest purged address)
533 static void __purge_vmap_area_lazy(unsigned long *start
, unsigned long *end
,
534 int sync
, int force_flush
)
536 static DEFINE_SPINLOCK(purge_lock
);
538 struct vmap_area
*va
;
539 struct vmap_area
*n_va
;
543 * If sync is 0 but force_flush is 1, we'll go sync anyway but callers
544 * should not expect such behaviour. This just simplifies locking for
545 * the case that isn't actually used at the moment anyway.
547 if (!sync
&& !force_flush
) {
548 if (!spin_trylock(&purge_lock
))
551 spin_lock(&purge_lock
);
554 purge_fragmented_blocks_allcpus();
557 list_for_each_entry_rcu(va
, &vmap_area_list
, list
) {
558 if (va
->flags
& VM_LAZY_FREE
) {
559 if (va
->va_start
< *start
)
560 *start
= va
->va_start
;
561 if (va
->va_end
> *end
)
563 nr
+= (va
->va_end
- va
->va_start
) >> PAGE_SHIFT
;
564 list_add_tail(&va
->purge_list
, &valist
);
565 va
->flags
|= VM_LAZY_FREEING
;
566 va
->flags
&= ~VM_LAZY_FREE
;
572 atomic_sub(nr
, &vmap_lazy_nr
);
574 if (nr
|| force_flush
)
575 flush_tlb_kernel_range(*start
, *end
);
578 spin_lock(&vmap_area_lock
);
579 list_for_each_entry_safe(va
, n_va
, &valist
, purge_list
)
580 __free_vmap_area(va
);
581 spin_unlock(&vmap_area_lock
);
583 spin_unlock(&purge_lock
);
587 * Kick off a purge of the outstanding lazy areas. Don't bother if somebody
588 * is already purging.
590 static void try_purge_vmap_area_lazy(void)
592 unsigned long start
= ULONG_MAX
, end
= 0;
594 __purge_vmap_area_lazy(&start
, &end
, 0, 0);
598 * Kick off a purge of the outstanding lazy areas.
600 static void purge_vmap_area_lazy(void)
602 unsigned long start
= ULONG_MAX
, end
= 0;
604 __purge_vmap_area_lazy(&start
, &end
, 1, 0);
608 * Free a vmap area, caller ensuring that the area has been unmapped
609 * and flush_cache_vunmap had been called for the correct range
612 static void free_vmap_area_noflush(struct vmap_area
*va
)
614 va
->flags
|= VM_LAZY_FREE
;
615 atomic_add((va
->va_end
- va
->va_start
) >> PAGE_SHIFT
, &vmap_lazy_nr
);
616 if (unlikely(atomic_read(&vmap_lazy_nr
) > lazy_max_pages()))
617 try_purge_vmap_area_lazy();
621 * Free and unmap a vmap area, caller ensuring flush_cache_vunmap had been
622 * called for the correct range previously.
624 static void free_unmap_vmap_area_noflush(struct vmap_area
*va
)
627 free_vmap_area_noflush(va
);
631 * Free and unmap a vmap area
633 static void free_unmap_vmap_area(struct vmap_area
*va
)
635 flush_cache_vunmap(va
->va_start
, va
->va_end
);
636 free_unmap_vmap_area_noflush(va
);
639 static struct vmap_area
*find_vmap_area(unsigned long addr
)
641 struct vmap_area
*va
;
643 spin_lock(&vmap_area_lock
);
644 va
= __find_vmap_area(addr
);
645 spin_unlock(&vmap_area_lock
);
650 static void free_unmap_vmap_area_addr(unsigned long addr
)
652 struct vmap_area
*va
;
654 va
= find_vmap_area(addr
);
656 free_unmap_vmap_area(va
);
660 /*** Per cpu kva allocator ***/
663 * vmap space is limited especially on 32 bit architectures. Ensure there is
664 * room for at least 16 percpu vmap blocks per CPU.
667 * If we had a constant VMALLOC_START and VMALLOC_END, we'd like to be able
668 * to #define VMALLOC_SPACE (VMALLOC_END-VMALLOC_START). Guess
669 * instead (we just need a rough idea)
671 #if BITS_PER_LONG == 32
672 #define VMALLOC_SPACE (128UL*1024*1024)
674 #define VMALLOC_SPACE (128UL*1024*1024*1024)
677 #define VMALLOC_PAGES (VMALLOC_SPACE / PAGE_SIZE)
678 #define VMAP_MAX_ALLOC BITS_PER_LONG /* 256K with 4K pages */
679 #define VMAP_BBMAP_BITS_MAX 1024 /* 4MB with 4K pages */
680 #define VMAP_BBMAP_BITS_MIN (VMAP_MAX_ALLOC*2)
681 #define VMAP_MIN(x, y) ((x) < (y) ? (x) : (y)) /* can't use min() */
682 #define VMAP_MAX(x, y) ((x) > (y) ? (x) : (y)) /* can't use max() */
683 #define VMAP_BBMAP_BITS VMAP_MIN(VMAP_BBMAP_BITS_MAX, \
684 VMAP_MAX(VMAP_BBMAP_BITS_MIN, \
685 VMALLOC_PAGES / NR_CPUS / 16))
687 #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE)
689 static bool vmap_initialized __read_mostly
= false;
691 struct vmap_block_queue
{
693 struct list_head free
;
698 struct vmap_area
*va
;
699 struct vmap_block_queue
*vbq
;
700 unsigned long free
, dirty
;
701 DECLARE_BITMAP(alloc_map
, VMAP_BBMAP_BITS
);
702 DECLARE_BITMAP(dirty_map
, VMAP_BBMAP_BITS
);
703 struct list_head free_list
;
704 struct rcu_head rcu_head
;
705 struct list_head purge
;
708 /* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
709 static DEFINE_PER_CPU(struct vmap_block_queue
, vmap_block_queue
);
712 * Radix tree of vmap blocks, indexed by address, to quickly find a vmap block
713 * in the free path. Could get rid of this if we change the API to return a
714 * "cookie" from alloc, to be passed to free. But no big deal yet.
716 static DEFINE_SPINLOCK(vmap_block_tree_lock
);
717 static RADIX_TREE(vmap_block_tree
, GFP_ATOMIC
);
720 * We should probably have a fallback mechanism to allocate virtual memory
721 * out of partially filled vmap blocks. However vmap block sizing should be
722 * fairly reasonable according to the vmalloc size, so it shouldn't be a
726 static unsigned long addr_to_vb_idx(unsigned long addr
)
728 addr
-= VMALLOC_START
& ~(VMAP_BLOCK_SIZE
-1);
729 addr
/= VMAP_BLOCK_SIZE
;
733 static struct vmap_block
*new_vmap_block(gfp_t gfp_mask
)
735 struct vmap_block_queue
*vbq
;
736 struct vmap_block
*vb
;
737 struct vmap_area
*va
;
738 unsigned long vb_idx
;
741 node
= numa_node_id();
743 vb
= kmalloc_node(sizeof(struct vmap_block
),
744 gfp_mask
& GFP_RECLAIM_MASK
, node
);
746 return ERR_PTR(-ENOMEM
);
748 va
= alloc_vmap_area(VMAP_BLOCK_SIZE
, VMAP_BLOCK_SIZE
,
749 VMALLOC_START
, VMALLOC_END
,
756 err
= radix_tree_preload(gfp_mask
);
763 spin_lock_init(&vb
->lock
);
765 vb
->free
= VMAP_BBMAP_BITS
;
767 bitmap_zero(vb
->alloc_map
, VMAP_BBMAP_BITS
);
768 bitmap_zero(vb
->dirty_map
, VMAP_BBMAP_BITS
);
769 INIT_LIST_HEAD(&vb
->free_list
);
771 vb_idx
= addr_to_vb_idx(va
->va_start
);
772 spin_lock(&vmap_block_tree_lock
);
773 err
= radix_tree_insert(&vmap_block_tree
, vb_idx
, vb
);
774 spin_unlock(&vmap_block_tree_lock
);
776 radix_tree_preload_end();
778 vbq
= &get_cpu_var(vmap_block_queue
);
780 spin_lock(&vbq
->lock
);
781 list_add_rcu(&vb
->free_list
, &vbq
->free
);
782 spin_unlock(&vbq
->lock
);
783 put_cpu_var(vmap_block_queue
);
788 static void rcu_free_vb(struct rcu_head
*head
)
790 struct vmap_block
*vb
= container_of(head
, struct vmap_block
, rcu_head
);
795 static void free_vmap_block(struct vmap_block
*vb
)
797 struct vmap_block
*tmp
;
798 unsigned long vb_idx
;
800 vb_idx
= addr_to_vb_idx(vb
->va
->va_start
);
801 spin_lock(&vmap_block_tree_lock
);
802 tmp
= radix_tree_delete(&vmap_block_tree
, vb_idx
);
803 spin_unlock(&vmap_block_tree_lock
);
806 free_vmap_area_noflush(vb
->va
);
807 call_rcu(&vb
->rcu_head
, rcu_free_vb
);
810 static void purge_fragmented_blocks(int cpu
)
813 struct vmap_block
*vb
;
814 struct vmap_block
*n_vb
;
815 struct vmap_block_queue
*vbq
= &per_cpu(vmap_block_queue
, cpu
);
818 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
820 if (!(vb
->free
+ vb
->dirty
== VMAP_BBMAP_BITS
&& vb
->dirty
!= VMAP_BBMAP_BITS
))
823 spin_lock(&vb
->lock
);
824 if (vb
->free
+ vb
->dirty
== VMAP_BBMAP_BITS
&& vb
->dirty
!= VMAP_BBMAP_BITS
) {
825 vb
->free
= 0; /* prevent further allocs after releasing lock */
826 vb
->dirty
= VMAP_BBMAP_BITS
; /* prevent purging it again */
827 bitmap_fill(vb
->alloc_map
, VMAP_BBMAP_BITS
);
828 bitmap_fill(vb
->dirty_map
, VMAP_BBMAP_BITS
);
829 spin_lock(&vbq
->lock
);
830 list_del_rcu(&vb
->free_list
);
831 spin_unlock(&vbq
->lock
);
832 spin_unlock(&vb
->lock
);
833 list_add_tail(&vb
->purge
, &purge
);
835 spin_unlock(&vb
->lock
);
839 list_for_each_entry_safe(vb
, n_vb
, &purge
, purge
) {
840 list_del(&vb
->purge
);
845 static void purge_fragmented_blocks_thiscpu(void)
847 purge_fragmented_blocks(smp_processor_id());
850 static void purge_fragmented_blocks_allcpus(void)
854 for_each_possible_cpu(cpu
)
855 purge_fragmented_blocks(cpu
);
858 static void *vb_alloc(unsigned long size
, gfp_t gfp_mask
)
860 struct vmap_block_queue
*vbq
;
861 struct vmap_block
*vb
;
862 unsigned long addr
= 0;
866 BUG_ON(size
& ~PAGE_MASK
);
867 BUG_ON(size
> PAGE_SIZE
*VMAP_MAX_ALLOC
);
868 order
= get_order(size
);
872 vbq
= &get_cpu_var(vmap_block_queue
);
873 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
876 spin_lock(&vb
->lock
);
877 if (vb
->free
< 1UL << order
)
880 i
= bitmap_find_free_region(vb
->alloc_map
,
881 VMAP_BBMAP_BITS
, order
);
884 if (vb
->free
+ vb
->dirty
== VMAP_BBMAP_BITS
) {
885 /* fragmented and no outstanding allocations */
886 BUG_ON(vb
->dirty
!= VMAP_BBMAP_BITS
);
891 addr
= vb
->va
->va_start
+ (i
<< PAGE_SHIFT
);
892 BUG_ON(addr_to_vb_idx(addr
) !=
893 addr_to_vb_idx(vb
->va
->va_start
));
894 vb
->free
-= 1UL << order
;
896 spin_lock(&vbq
->lock
);
897 list_del_rcu(&vb
->free_list
);
898 spin_unlock(&vbq
->lock
);
900 spin_unlock(&vb
->lock
);
903 spin_unlock(&vb
->lock
);
907 purge_fragmented_blocks_thiscpu();
909 put_cpu_var(vmap_block_queue
);
913 vb
= new_vmap_block(gfp_mask
);
922 static void vb_free(const void *addr
, unsigned long size
)
924 unsigned long offset
;
925 unsigned long vb_idx
;
927 struct vmap_block
*vb
;
929 BUG_ON(size
& ~PAGE_MASK
);
930 BUG_ON(size
> PAGE_SIZE
*VMAP_MAX_ALLOC
);
932 flush_cache_vunmap((unsigned long)addr
, (unsigned long)addr
+ size
);
934 order
= get_order(size
);
936 offset
= (unsigned long)addr
& (VMAP_BLOCK_SIZE
- 1);
938 vb_idx
= addr_to_vb_idx((unsigned long)addr
);
940 vb
= radix_tree_lookup(&vmap_block_tree
, vb_idx
);
944 vunmap_page_range((unsigned long)addr
, (unsigned long)addr
+ size
);
946 spin_lock(&vb
->lock
);
947 BUG_ON(bitmap_allocate_region(vb
->dirty_map
, offset
>> PAGE_SHIFT
, order
));
949 vb
->dirty
+= 1UL << order
;
950 if (vb
->dirty
== VMAP_BBMAP_BITS
) {
952 spin_unlock(&vb
->lock
);
955 spin_unlock(&vb
->lock
);
959 * vm_unmap_aliases - unmap outstanding lazy aliases in the vmap layer
961 * The vmap/vmalloc layer lazily flushes kernel virtual mappings primarily
962 * to amortize TLB flushing overheads. What this means is that any page you
963 * have now, may, in a former life, have been mapped into kernel virtual
964 * address by the vmap layer and so there might be some CPUs with TLB entries
965 * still referencing that page (additional to the regular 1:1 kernel mapping).
967 * vm_unmap_aliases flushes all such lazy mappings. After it returns, we can
968 * be sure that none of the pages we have control over will have any aliases
969 * from the vmap layer.
971 void vm_unmap_aliases(void)
973 unsigned long start
= ULONG_MAX
, end
= 0;
977 if (unlikely(!vmap_initialized
))
980 for_each_possible_cpu(cpu
) {
981 struct vmap_block_queue
*vbq
= &per_cpu(vmap_block_queue
, cpu
);
982 struct vmap_block
*vb
;
985 list_for_each_entry_rcu(vb
, &vbq
->free
, free_list
) {
988 spin_lock(&vb
->lock
);
989 i
= find_first_bit(vb
->dirty_map
, VMAP_BBMAP_BITS
);
990 while (i
< VMAP_BBMAP_BITS
) {
993 j
= find_next_zero_bit(vb
->dirty_map
,
996 s
= vb
->va
->va_start
+ (i
<< PAGE_SHIFT
);
997 e
= vb
->va
->va_start
+ (j
<< PAGE_SHIFT
);
1006 i
= find_next_bit(vb
->dirty_map
,
1007 VMAP_BBMAP_BITS
, i
);
1009 spin_unlock(&vb
->lock
);
1014 __purge_vmap_area_lazy(&start
, &end
, 1, flush
);
1016 EXPORT_SYMBOL_GPL(vm_unmap_aliases
);
1019 * vm_unmap_ram - unmap linear kernel address space set up by vm_map_ram
1020 * @mem: the pointer returned by vm_map_ram
1021 * @count: the count passed to that vm_map_ram call (cannot unmap partial)
1023 void vm_unmap_ram(const void *mem
, unsigned int count
)
1025 unsigned long size
= count
<< PAGE_SHIFT
;
1026 unsigned long addr
= (unsigned long)mem
;
1029 BUG_ON(addr
< VMALLOC_START
);
1030 BUG_ON(addr
> VMALLOC_END
);
1031 BUG_ON(addr
& (PAGE_SIZE
-1));
1033 debug_check_no_locks_freed(mem
, size
);
1034 vmap_debug_free_range(addr
, addr
+size
);
1036 if (likely(count
<= VMAP_MAX_ALLOC
))
1039 free_unmap_vmap_area_addr(addr
);
1041 EXPORT_SYMBOL(vm_unmap_ram
);
1044 * vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
1045 * @pages: an array of pointers to the pages to be mapped
1046 * @count: number of pages
1047 * @node: prefer to allocate data structures on this node
1048 * @prot: memory protection to use. PAGE_KERNEL for regular RAM
1050 * Returns: a pointer to the address that has been mapped, or %NULL on failure
1052 void *vm_map_ram(struct page
**pages
, unsigned int count
, int node
, pgprot_t prot
)
1054 unsigned long size
= count
<< PAGE_SHIFT
;
1058 if (likely(count
<= VMAP_MAX_ALLOC
)) {
1059 mem
= vb_alloc(size
, GFP_KERNEL
);
1062 addr
= (unsigned long)mem
;
1064 struct vmap_area
*va
;
1065 va
= alloc_vmap_area(size
, PAGE_SIZE
,
1066 VMALLOC_START
, VMALLOC_END
, node
, GFP_KERNEL
);
1070 addr
= va
->va_start
;
1073 if (vmap_page_range(addr
, addr
+ size
, prot
, pages
) < 0) {
1074 vm_unmap_ram(mem
, count
);
1079 EXPORT_SYMBOL(vm_map_ram
);
1082 * vm_area_register_early - register vmap area early during boot
1083 * @vm: vm_struct to register
1084 * @align: requested alignment
1086 * This function is used to register kernel vm area before
1087 * vmalloc_init() is called. @vm->size and @vm->flags should contain
1088 * proper values on entry and other fields should be zero. On return,
1089 * vm->addr contains the allocated address.
1091 * DO NOT USE THIS FUNCTION UNLESS YOU KNOW WHAT YOU'RE DOING.
1093 void __init
vm_area_register_early(struct vm_struct
*vm
, size_t align
)
1095 static size_t vm_init_off __initdata
;
1098 addr
= ALIGN(VMALLOC_START
+ vm_init_off
, align
);
1099 vm_init_off
= PFN_ALIGN(addr
+ vm
->size
) - VMALLOC_START
;
1101 vm
->addr
= (void *)addr
;
1107 void __init
vmalloc_init(void)
1109 struct vmap_area
*va
;
1110 struct vm_struct
*tmp
;
1113 for_each_possible_cpu(i
) {
1114 struct vmap_block_queue
*vbq
;
1116 vbq
= &per_cpu(vmap_block_queue
, i
);
1117 spin_lock_init(&vbq
->lock
);
1118 INIT_LIST_HEAD(&vbq
->free
);
1121 /* Import existing vmlist entries. */
1122 for (tmp
= vmlist
; tmp
; tmp
= tmp
->next
) {
1123 va
= kzalloc(sizeof(struct vmap_area
), GFP_NOWAIT
);
1124 va
->flags
= tmp
->flags
| VM_VM_AREA
;
1125 va
->va_start
= (unsigned long)tmp
->addr
;
1126 va
->va_end
= va
->va_start
+ tmp
->size
;
1127 __insert_vmap_area(va
);
1130 vmap_area_pcpu_hole
= VMALLOC_END
;
1132 vmap_initialized
= true;
1136 * map_kernel_range_noflush - map kernel VM area with the specified pages
1137 * @addr: start of the VM area to map
1138 * @size: size of the VM area to map
1139 * @prot: page protection flags to use
1140 * @pages: pages to map
1142 * Map PFN_UP(@size) pages at @addr. The VM area @addr and @size
1143 * specify should have been allocated using get_vm_area() and its
1147 * This function does NOT do any cache flushing. The caller is
1148 * responsible for calling flush_cache_vmap() on to-be-mapped areas
1149 * before calling this function.
1152 * The number of pages mapped on success, -errno on failure.
1154 int map_kernel_range_noflush(unsigned long addr
, unsigned long size
,
1155 pgprot_t prot
, struct page
**pages
)
1157 return vmap_page_range_noflush(addr
, addr
+ size
, prot
, pages
);
1161 * unmap_kernel_range_noflush - unmap kernel VM area
1162 * @addr: start of the VM area to unmap
1163 * @size: size of the VM area to unmap
1165 * Unmap PFN_UP(@size) pages at @addr. The VM area @addr and @size
1166 * specify should have been allocated using get_vm_area() and its
1170 * This function does NOT do any cache flushing. The caller is
1171 * responsible for calling flush_cache_vunmap() on to-be-mapped areas
1172 * before calling this function and flush_tlb_kernel_range() after.
1174 void unmap_kernel_range_noflush(unsigned long addr
, unsigned long size
)
1176 vunmap_page_range(addr
, addr
+ size
);
1180 * unmap_kernel_range - unmap kernel VM area and flush cache and TLB
1181 * @addr: start of the VM area to unmap
1182 * @size: size of the VM area to unmap
1184 * Similar to unmap_kernel_range_noflush() but flushes vcache before
1185 * the unmapping and tlb after.
1187 void unmap_kernel_range(unsigned long addr
, unsigned long size
)
1189 unsigned long end
= addr
+ size
;
1191 flush_cache_vunmap(addr
, end
);
1192 vunmap_page_range(addr
, end
);
1193 flush_tlb_kernel_range(addr
, end
);
1196 int map_vm_area(struct vm_struct
*area
, pgprot_t prot
, struct page
***pages
)
1198 unsigned long addr
= (unsigned long)area
->addr
;
1199 unsigned long end
= addr
+ area
->size
- PAGE_SIZE
;
1202 err
= vmap_page_range(addr
, end
, prot
, *pages
);
1210 EXPORT_SYMBOL_GPL(map_vm_area
);
1212 /*** Old vmalloc interfaces ***/
1213 DEFINE_RWLOCK(vmlist_lock
);
1214 struct vm_struct
*vmlist
;
1216 static void insert_vmalloc_vm(struct vm_struct
*vm
, struct vmap_area
*va
,
1217 unsigned long flags
, void *caller
)
1219 struct vm_struct
*tmp
, **p
;
1222 vm
->addr
= (void *)va
->va_start
;
1223 vm
->size
= va
->va_end
- va
->va_start
;
1224 vm
->caller
= caller
;
1226 va
->flags
|= VM_VM_AREA
;
1228 write_lock(&vmlist_lock
);
1229 for (p
= &vmlist
; (tmp
= *p
) != NULL
; p
= &tmp
->next
) {
1230 if (tmp
->addr
>= vm
->addr
)
1235 write_unlock(&vmlist_lock
);
1238 static struct vm_struct
*__get_vm_area_node(unsigned long size
,
1239 unsigned long align
, unsigned long flags
, unsigned long start
,
1240 unsigned long end
, int node
, gfp_t gfp_mask
, void *caller
)
1242 static struct vmap_area
*va
;
1243 struct vm_struct
*area
;
1245 BUG_ON(in_interrupt());
1246 if (flags
& VM_IOREMAP
) {
1247 int bit
= fls(size
);
1249 if (bit
> IOREMAP_MAX_ORDER
)
1250 bit
= IOREMAP_MAX_ORDER
;
1251 else if (bit
< PAGE_SHIFT
)
1257 size
= PAGE_ALIGN(size
);
1258 if (unlikely(!size
))
1261 area
= kzalloc_node(sizeof(*area
), gfp_mask
& GFP_RECLAIM_MASK
, node
);
1262 if (unlikely(!area
))
1266 * We always allocate a guard page.
1270 va
= alloc_vmap_area(size
, align
, start
, end
, node
, gfp_mask
);
1276 insert_vmalloc_vm(area
, va
, flags
, caller
);
1280 struct vm_struct
*__get_vm_area(unsigned long size
, unsigned long flags
,
1281 unsigned long start
, unsigned long end
)
1283 return __get_vm_area_node(size
, 1, flags
, start
, end
, -1, GFP_KERNEL
,
1284 __builtin_return_address(0));
1286 EXPORT_SYMBOL_GPL(__get_vm_area
);
1288 struct vm_struct
*__get_vm_area_caller(unsigned long size
, unsigned long flags
,
1289 unsigned long start
, unsigned long end
,
1292 return __get_vm_area_node(size
, 1, flags
, start
, end
, -1, GFP_KERNEL
,
1297 * get_vm_area - reserve a contiguous kernel virtual area
1298 * @size: size of the area
1299 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
1301 * Search an area of @size in the kernel virtual mapping area,
1302 * and reserved it for out purposes. Returns the area descriptor
1303 * on success or %NULL on failure.
1305 struct vm_struct
*get_vm_area(unsigned long size
, unsigned long flags
)
1307 return __get_vm_area_node(size
, 1, flags
, VMALLOC_START
, VMALLOC_END
,
1308 -1, GFP_KERNEL
, __builtin_return_address(0));
1311 struct vm_struct
*get_vm_area_caller(unsigned long size
, unsigned long flags
,
1314 return __get_vm_area_node(size
, 1, flags
, VMALLOC_START
, VMALLOC_END
,
1315 -1, GFP_KERNEL
, caller
);
1318 static struct vm_struct
*find_vm_area(const void *addr
)
1320 struct vmap_area
*va
;
1322 va
= find_vmap_area((unsigned long)addr
);
1323 if (va
&& va
->flags
& VM_VM_AREA
)
1330 * remove_vm_area - find and remove a continuous kernel virtual area
1331 * @addr: base address
1333 * Search for the kernel VM area starting at @addr, and remove it.
1334 * This function returns the found VM area, but using it is NOT safe
1335 * on SMP machines, except for its size or flags.
1337 struct vm_struct
*remove_vm_area(const void *addr
)
1339 struct vmap_area
*va
;
1341 va
= find_vmap_area((unsigned long)addr
);
1342 if (va
&& va
->flags
& VM_VM_AREA
) {
1343 struct vm_struct
*vm
= va
->private;
1344 struct vm_struct
*tmp
, **p
;
1346 * remove from list and disallow access to this vm_struct
1347 * before unmap. (address range confliction is maintained by
1350 write_lock(&vmlist_lock
);
1351 for (p
= &vmlist
; (tmp
= *p
) != vm
; p
= &tmp
->next
)
1354 write_unlock(&vmlist_lock
);
1356 vmap_debug_free_range(va
->va_start
, va
->va_end
);
1357 free_unmap_vmap_area(va
);
1358 vm
->size
-= PAGE_SIZE
;
1365 static void __vunmap(const void *addr
, int deallocate_pages
)
1367 struct vm_struct
*area
;
1372 if ((PAGE_SIZE
-1) & (unsigned long)addr
) {
1373 WARN(1, KERN_ERR
"Trying to vfree() bad address (%p)\n", addr
);
1377 area
= remove_vm_area(addr
);
1378 if (unlikely(!area
)) {
1379 WARN(1, KERN_ERR
"Trying to vfree() nonexistent vm area (%p)\n",
1384 debug_check_no_locks_freed(addr
, area
->size
);
1385 debug_check_no_obj_freed(addr
, area
->size
);
1387 if (deallocate_pages
) {
1390 for (i
= 0; i
< area
->nr_pages
; i
++) {
1391 struct page
*page
= area
->pages
[i
];
1397 if (area
->flags
& VM_VPAGES
)
1408 * vfree - release memory allocated by vmalloc()
1409 * @addr: memory base address
1411 * Free the virtually continuous memory area starting at @addr, as
1412 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
1413 * NULL, no operation is performed.
1415 * Must not be called in interrupt context.
1417 void vfree(const void *addr
)
1419 BUG_ON(in_interrupt());
1421 kmemleak_free(addr
);
1425 EXPORT_SYMBOL(vfree
);
1428 * vunmap - release virtual mapping obtained by vmap()
1429 * @addr: memory base address
1431 * Free the virtually contiguous memory area starting at @addr,
1432 * which was created from the page array passed to vmap().
1434 * Must not be called in interrupt context.
1436 void vunmap(const void *addr
)
1438 BUG_ON(in_interrupt());
1442 EXPORT_SYMBOL(vunmap
);
1445 * vmap - map an array of pages into virtually contiguous space
1446 * @pages: array of page pointers
1447 * @count: number of pages to map
1448 * @flags: vm_area->flags
1449 * @prot: page protection for the mapping
1451 * Maps @count pages from @pages into contiguous kernel virtual
1454 void *vmap(struct page
**pages
, unsigned int count
,
1455 unsigned long flags
, pgprot_t prot
)
1457 struct vm_struct
*area
;
1461 if (count
> totalram_pages
)
1464 area
= get_vm_area_caller((count
<< PAGE_SHIFT
), flags
,
1465 __builtin_return_address(0));
1469 if (map_vm_area(area
, prot
, &pages
)) {
1476 EXPORT_SYMBOL(vmap
);
1478 static void *__vmalloc_node(unsigned long size
, unsigned long align
,
1479 gfp_t gfp_mask
, pgprot_t prot
,
1480 int node
, void *caller
);
1481 static void *__vmalloc_area_node(struct vm_struct
*area
, gfp_t gfp_mask
,
1482 pgprot_t prot
, int node
, void *caller
)
1484 struct page
**pages
;
1485 unsigned int nr_pages
, array_size
, i
;
1486 gfp_t nested_gfp
= (gfp_mask
& GFP_RECLAIM_MASK
) | __GFP_ZERO
;
1488 nr_pages
= (area
->size
- PAGE_SIZE
) >> PAGE_SHIFT
;
1489 array_size
= (nr_pages
* sizeof(struct page
*));
1491 area
->nr_pages
= nr_pages
;
1492 /* Please note that the recursion is strictly bounded. */
1493 if (array_size
> PAGE_SIZE
) {
1494 pages
= __vmalloc_node(array_size
, 1, nested_gfp
|__GFP_HIGHMEM
,
1495 PAGE_KERNEL
, node
, caller
);
1496 area
->flags
|= VM_VPAGES
;
1498 pages
= kmalloc_node(array_size
, nested_gfp
, node
);
1500 area
->pages
= pages
;
1501 area
->caller
= caller
;
1503 remove_vm_area(area
->addr
);
1508 for (i
= 0; i
< area
->nr_pages
; i
++) {
1512 page
= alloc_page(gfp_mask
);
1514 page
= alloc_pages_node(node
, gfp_mask
, 0);
1516 if (unlikely(!page
)) {
1517 /* Successfully allocated i pages, free them in __vunmap() */
1521 area
->pages
[i
] = page
;
1524 if (map_vm_area(area
, prot
, &pages
))
1534 * __vmalloc_node_range - allocate virtually contiguous memory
1535 * @size: allocation size
1536 * @align: desired alignment
1537 * @start: vm area range start
1538 * @end: vm area range end
1539 * @gfp_mask: flags for the page level allocator
1540 * @prot: protection mask for the allocated pages
1541 * @node: node to use for allocation or -1
1542 * @caller: caller's return address
1544 * Allocate enough pages to cover @size from the page level
1545 * allocator with @gfp_mask flags. Map them into contiguous
1546 * kernel virtual space, using a pagetable protection of @prot.
1548 void *__vmalloc_node_range(unsigned long size
, unsigned long align
,
1549 unsigned long start
, unsigned long end
, gfp_t gfp_mask
,
1550 pgprot_t prot
, int node
, void *caller
)
1552 struct vm_struct
*area
;
1554 unsigned long real_size
= size
;
1556 size
= PAGE_ALIGN(size
);
1557 if (!size
|| (size
>> PAGE_SHIFT
) > totalram_pages
)
1560 area
= __get_vm_area_node(size
, align
, VM_ALLOC
, start
, end
, node
,
1566 addr
= __vmalloc_area_node(area
, gfp_mask
, prot
, node
, caller
);
1569 * A ref_count = 3 is needed because the vm_struct and vmap_area
1570 * structures allocated in the __get_vm_area_node() function contain
1571 * references to the virtual address of the vmalloc'ed block.
1573 kmemleak_alloc(addr
, real_size
, 3, gfp_mask
);
1579 * __vmalloc_node - allocate virtually contiguous memory
1580 * @size: allocation size
1581 * @align: desired alignment
1582 * @gfp_mask: flags for the page level allocator
1583 * @prot: protection mask for the allocated pages
1584 * @node: node to use for allocation or -1
1585 * @caller: caller's return address
1587 * Allocate enough pages to cover @size from the page level
1588 * allocator with @gfp_mask flags. Map them into contiguous
1589 * kernel virtual space, using a pagetable protection of @prot.
1591 static void *__vmalloc_node(unsigned long size
, unsigned long align
,
1592 gfp_t gfp_mask
, pgprot_t prot
,
1593 int node
, void *caller
)
1595 return __vmalloc_node_range(size
, align
, VMALLOC_START
, VMALLOC_END
,
1596 gfp_mask
, prot
, node
, caller
);
1599 void *__vmalloc(unsigned long size
, gfp_t gfp_mask
, pgprot_t prot
)
1601 return __vmalloc_node(size
, 1, gfp_mask
, prot
, -1,
1602 __builtin_return_address(0));
1604 EXPORT_SYMBOL(__vmalloc
);
1606 static inline void *__vmalloc_node_flags(unsigned long size
,
1607 int node
, gfp_t flags
)
1609 return __vmalloc_node(size
, 1, flags
, PAGE_KERNEL
,
1610 node
, __builtin_return_address(0));
1614 * vmalloc - allocate virtually contiguous memory
1615 * @size: allocation size
1616 * Allocate enough pages to cover @size from the page level
1617 * allocator and map them into contiguous kernel virtual space.
1619 * For tight control over page level allocator and protection flags
1620 * use __vmalloc() instead.
1622 void *vmalloc(unsigned long size
)
1624 return __vmalloc_node_flags(size
, -1, GFP_KERNEL
| __GFP_HIGHMEM
);
1626 EXPORT_SYMBOL(vmalloc
);
1629 * vzalloc - allocate virtually contiguous memory with zero fill
1630 * @size: allocation size
1631 * Allocate enough pages to cover @size from the page level
1632 * allocator and map them into contiguous kernel virtual space.
1633 * The memory allocated is set to zero.
1635 * For tight control over page level allocator and protection flags
1636 * use __vmalloc() instead.
1638 void *vzalloc(unsigned long size
)
1640 return __vmalloc_node_flags(size
, -1,
1641 GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_ZERO
);
1643 EXPORT_SYMBOL(vzalloc
);
1646 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
1647 * @size: allocation size
1649 * The resulting memory area is zeroed so it can be mapped to userspace
1650 * without leaking data.
1652 void *vmalloc_user(unsigned long size
)
1654 struct vm_struct
*area
;
1657 ret
= __vmalloc_node(size
, SHMLBA
,
1658 GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_ZERO
,
1659 PAGE_KERNEL
, -1, __builtin_return_address(0));
1661 area
= find_vm_area(ret
);
1662 area
->flags
|= VM_USERMAP
;
1666 EXPORT_SYMBOL(vmalloc_user
);
1669 * vmalloc_node - allocate memory on a specific node
1670 * @size: allocation size
1673 * Allocate enough pages to cover @size from the page level
1674 * allocator and map them into contiguous kernel virtual space.
1676 * For tight control over page level allocator and protection flags
1677 * use __vmalloc() instead.
1679 void *vmalloc_node(unsigned long size
, int node
)
1681 return __vmalloc_node(size
, 1, GFP_KERNEL
| __GFP_HIGHMEM
, PAGE_KERNEL
,
1682 node
, __builtin_return_address(0));
1684 EXPORT_SYMBOL(vmalloc_node
);
1687 * vzalloc_node - allocate memory on a specific node with zero fill
1688 * @size: allocation size
1691 * Allocate enough pages to cover @size from the page level
1692 * allocator and map them into contiguous kernel virtual space.
1693 * The memory allocated is set to zero.
1695 * For tight control over page level allocator and protection flags
1696 * use __vmalloc_node() instead.
1698 void *vzalloc_node(unsigned long size
, int node
)
1700 return __vmalloc_node_flags(size
, node
,
1701 GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_ZERO
);
1703 EXPORT_SYMBOL(vzalloc_node
);
1705 #ifndef PAGE_KERNEL_EXEC
1706 # define PAGE_KERNEL_EXEC PAGE_KERNEL
1710 * vmalloc_exec - allocate virtually contiguous, executable memory
1711 * @size: allocation size
1713 * Kernel-internal function to allocate enough pages to cover @size
1714 * the page level allocator and map them into contiguous and
1715 * executable kernel virtual space.
1717 * For tight control over page level allocator and protection flags
1718 * use __vmalloc() instead.
1721 void *vmalloc_exec(unsigned long size
)
1723 return __vmalloc_node(size
, 1, GFP_KERNEL
| __GFP_HIGHMEM
, PAGE_KERNEL_EXEC
,
1724 -1, __builtin_return_address(0));
1727 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
1728 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
1729 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
1730 #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
1732 #define GFP_VMALLOC32 GFP_KERNEL
1736 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
1737 * @size: allocation size
1739 * Allocate enough 32bit PA addressable pages to cover @size from the
1740 * page level allocator and map them into contiguous kernel virtual space.
1742 void *vmalloc_32(unsigned long size
)
1744 return __vmalloc_node(size
, 1, GFP_VMALLOC32
, PAGE_KERNEL
,
1745 -1, __builtin_return_address(0));
1747 EXPORT_SYMBOL(vmalloc_32
);
1750 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
1751 * @size: allocation size
1753 * The resulting memory area is 32bit addressable and zeroed so it can be
1754 * mapped to userspace without leaking data.
1756 void *vmalloc_32_user(unsigned long size
)
1758 struct vm_struct
*area
;
1761 ret
= __vmalloc_node(size
, 1, GFP_VMALLOC32
| __GFP_ZERO
, PAGE_KERNEL
,
1762 -1, __builtin_return_address(0));
1764 area
= find_vm_area(ret
);
1765 area
->flags
|= VM_USERMAP
;
1769 EXPORT_SYMBOL(vmalloc_32_user
);
1772 * small helper routine , copy contents to buf from addr.
1773 * If the page is not present, fill zero.
1776 static int aligned_vread(char *buf
, char *addr
, unsigned long count
)
1782 unsigned long offset
, length
;
1784 offset
= (unsigned long)addr
& ~PAGE_MASK
;
1785 length
= PAGE_SIZE
- offset
;
1788 p
= vmalloc_to_page(addr
);
1790 * To do safe access to this _mapped_ area, we need
1791 * lock. But adding lock here means that we need to add
1792 * overhead of vmalloc()/vfree() calles for this _debug_
1793 * interface, rarely used. Instead of that, we'll use
1794 * kmap() and get small overhead in this access function.
1798 * we can expect USER0 is not used (see vread/vwrite's
1799 * function description)
1801 void *map
= kmap_atomic(p
, KM_USER0
);
1802 memcpy(buf
, map
+ offset
, length
);
1803 kunmap_atomic(map
, KM_USER0
);
1805 memset(buf
, 0, length
);
1815 static int aligned_vwrite(char *buf
, char *addr
, unsigned long count
)
1821 unsigned long offset
, length
;
1823 offset
= (unsigned long)addr
& ~PAGE_MASK
;
1824 length
= PAGE_SIZE
- offset
;
1827 p
= vmalloc_to_page(addr
);
1829 * To do safe access to this _mapped_ area, we need
1830 * lock. But adding lock here means that we need to add
1831 * overhead of vmalloc()/vfree() calles for this _debug_
1832 * interface, rarely used. Instead of that, we'll use
1833 * kmap() and get small overhead in this access function.
1837 * we can expect USER0 is not used (see vread/vwrite's
1838 * function description)
1840 void *map
= kmap_atomic(p
, KM_USER0
);
1841 memcpy(map
+ offset
, buf
, length
);
1842 kunmap_atomic(map
, KM_USER0
);
1853 * vread() - read vmalloc area in a safe way.
1854 * @buf: buffer for reading data
1855 * @addr: vm address.
1856 * @count: number of bytes to be read.
1858 * Returns # of bytes which addr and buf should be increased.
1859 * (same number to @count). Returns 0 if [addr...addr+count) doesn't
1860 * includes any intersect with alive vmalloc area.
1862 * This function checks that addr is a valid vmalloc'ed area, and
1863 * copy data from that area to a given buffer. If the given memory range
1864 * of [addr...addr+count) includes some valid address, data is copied to
1865 * proper area of @buf. If there are memory holes, they'll be zero-filled.
1866 * IOREMAP area is treated as memory hole and no copy is done.
1868 * If [addr...addr+count) doesn't includes any intersects with alive
1869 * vm_struct area, returns 0.
1870 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1871 * the caller should guarantee KM_USER0 is not used.
1873 * Note: In usual ops, vread() is never necessary because the caller
1874 * should know vmalloc() area is valid and can use memcpy().
1875 * This is for routines which have to access vmalloc area without
1876 * any informaion, as /dev/kmem.
1880 long vread(char *buf
, char *addr
, unsigned long count
)
1882 struct vm_struct
*tmp
;
1883 char *vaddr
, *buf_start
= buf
;
1884 unsigned long buflen
= count
;
1887 /* Don't allow overflow */
1888 if ((unsigned long) addr
+ count
< count
)
1889 count
= -(unsigned long) addr
;
1891 read_lock(&vmlist_lock
);
1892 for (tmp
= vmlist
; count
&& tmp
; tmp
= tmp
->next
) {
1893 vaddr
= (char *) tmp
->addr
;
1894 if (addr
>= vaddr
+ tmp
->size
- PAGE_SIZE
)
1896 while (addr
< vaddr
) {
1904 n
= vaddr
+ tmp
->size
- PAGE_SIZE
- addr
;
1907 if (!(tmp
->flags
& VM_IOREMAP
))
1908 aligned_vread(buf
, addr
, n
);
1909 else /* IOREMAP area is treated as memory hole */
1916 read_unlock(&vmlist_lock
);
1918 if (buf
== buf_start
)
1920 /* zero-fill memory holes */
1921 if (buf
!= buf_start
+ buflen
)
1922 memset(buf
, 0, buflen
- (buf
- buf_start
));
1928 * vwrite() - write vmalloc area in a safe way.
1929 * @buf: buffer for source data
1930 * @addr: vm address.
1931 * @count: number of bytes to be read.
1933 * Returns # of bytes which addr and buf should be incresed.
1934 * (same number to @count).
1935 * If [addr...addr+count) doesn't includes any intersect with valid
1936 * vmalloc area, returns 0.
1938 * This function checks that addr is a valid vmalloc'ed area, and
1939 * copy data from a buffer to the given addr. If specified range of
1940 * [addr...addr+count) includes some valid address, data is copied from
1941 * proper area of @buf. If there are memory holes, no copy to hole.
1942 * IOREMAP area is treated as memory hole and no copy is done.
1944 * If [addr...addr+count) doesn't includes any intersects with alive
1945 * vm_struct area, returns 0.
1946 * @buf should be kernel's buffer. Because this function uses KM_USER0,
1947 * the caller should guarantee KM_USER0 is not used.
1949 * Note: In usual ops, vwrite() is never necessary because the caller
1950 * should know vmalloc() area is valid and can use memcpy().
1951 * This is for routines which have to access vmalloc area without
1952 * any informaion, as /dev/kmem.
1954 * The caller should guarantee KM_USER1 is not used.
1957 long vwrite(char *buf
, char *addr
, unsigned long count
)
1959 struct vm_struct
*tmp
;
1961 unsigned long n
, buflen
;
1964 /* Don't allow overflow */
1965 if ((unsigned long) addr
+ count
< count
)
1966 count
= -(unsigned long) addr
;
1969 read_lock(&vmlist_lock
);
1970 for (tmp
= vmlist
; count
&& tmp
; tmp
= tmp
->next
) {
1971 vaddr
= (char *) tmp
->addr
;
1972 if (addr
>= vaddr
+ tmp
->size
- PAGE_SIZE
)
1974 while (addr
< vaddr
) {
1981 n
= vaddr
+ tmp
->size
- PAGE_SIZE
- addr
;
1984 if (!(tmp
->flags
& VM_IOREMAP
)) {
1985 aligned_vwrite(buf
, addr
, n
);
1993 read_unlock(&vmlist_lock
);
2000 * remap_vmalloc_range - map vmalloc pages to userspace
2001 * @vma: vma to cover (map full range of vma)
2002 * @addr: vmalloc memory
2003 * @pgoff: number of pages into addr before first page to map
2005 * Returns: 0 for success, -Exxx on failure
2007 * This function checks that addr is a valid vmalloc'ed area, and
2008 * that it is big enough to cover the vma. Will return failure if
2009 * that criteria isn't met.
2011 * Similar to remap_pfn_range() (see mm/memory.c)
2013 int remap_vmalloc_range(struct vm_area_struct
*vma
, void *addr
,
2014 unsigned long pgoff
)
2016 struct vm_struct
*area
;
2017 unsigned long uaddr
= vma
->vm_start
;
2018 unsigned long usize
= vma
->vm_end
- vma
->vm_start
;
2020 if ((PAGE_SIZE
-1) & (unsigned long)addr
)
2023 area
= find_vm_area(addr
);
2027 if (!(area
->flags
& VM_USERMAP
))
2030 if (usize
+ (pgoff
<< PAGE_SHIFT
) > area
->size
- PAGE_SIZE
)
2033 addr
+= pgoff
<< PAGE_SHIFT
;
2035 struct page
*page
= vmalloc_to_page(addr
);
2038 ret
= vm_insert_page(vma
, uaddr
, page
);
2045 } while (usize
> 0);
2047 /* Prevent "things" like memory migration? VM_flags need a cleanup... */
2048 vma
->vm_flags
|= VM_RESERVED
;
2052 EXPORT_SYMBOL(remap_vmalloc_range
);
2055 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
2058 void __attribute__((weak
)) vmalloc_sync_all(void)
2063 static int f(pte_t
*pte
, pgtable_t table
, unsigned long addr
, void *data
)
2065 /* apply_to_page_range() does all the hard work. */
2070 * alloc_vm_area - allocate a range of kernel address space
2071 * @size: size of the area
2073 * Returns: NULL on failure, vm_struct on success
2075 * This function reserves a range of kernel address space, and
2076 * allocates pagetables to map that range. No actual mappings
2077 * are created. If the kernel address space is not shared
2078 * between processes, it syncs the pagetable across all
2081 struct vm_struct
*alloc_vm_area(size_t size
)
2083 struct vm_struct
*area
;
2085 area
= get_vm_area_caller(size
, VM_IOREMAP
,
2086 __builtin_return_address(0));
2091 * This ensures that page tables are constructed for this region
2092 * of kernel virtual address space and mapped into init_mm.
2094 if (apply_to_page_range(&init_mm
, (unsigned long)area
->addr
,
2095 area
->size
, f
, NULL
)) {
2100 /* Make sure the pagetables are constructed in process kernel
2106 EXPORT_SYMBOL_GPL(alloc_vm_area
);
2108 void free_vm_area(struct vm_struct
*area
)
2110 struct vm_struct
*ret
;
2111 ret
= remove_vm_area(area
->addr
);
2112 BUG_ON(ret
!= area
);
2115 EXPORT_SYMBOL_GPL(free_vm_area
);
2118 static struct vmap_area
*node_to_va(struct rb_node
*n
)
2120 return n
? rb_entry(n
, struct vmap_area
, rb_node
) : NULL
;
2124 * pvm_find_next_prev - find the next and prev vmap_area surrounding @end
2125 * @end: target address
2126 * @pnext: out arg for the next vmap_area
2127 * @pprev: out arg for the previous vmap_area
2129 * Returns: %true if either or both of next and prev are found,
2130 * %false if no vmap_area exists
2132 * Find vmap_areas end addresses of which enclose @end. ie. if not
2133 * NULL, *pnext->va_end > @end and *pprev->va_end <= @end.
2135 static bool pvm_find_next_prev(unsigned long end
,
2136 struct vmap_area
**pnext
,
2137 struct vmap_area
**pprev
)
2139 struct rb_node
*n
= vmap_area_root
.rb_node
;
2140 struct vmap_area
*va
= NULL
;
2143 va
= rb_entry(n
, struct vmap_area
, rb_node
);
2144 if (end
< va
->va_end
)
2146 else if (end
> va
->va_end
)
2155 if (va
->va_end
> end
) {
2157 *pprev
= node_to_va(rb_prev(&(*pnext
)->rb_node
));
2160 *pnext
= node_to_va(rb_next(&(*pprev
)->rb_node
));
2166 * pvm_determine_end - find the highest aligned address between two vmap_areas
2167 * @pnext: in/out arg for the next vmap_area
2168 * @pprev: in/out arg for the previous vmap_area
2171 * Returns: determined end address
2173 * Find the highest aligned address between *@pnext and *@pprev below
2174 * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned
2175 * down address is between the end addresses of the two vmap_areas.
2177 * Please note that the address returned by this function may fall
2178 * inside *@pnext vmap_area. The caller is responsible for checking
2181 static unsigned long pvm_determine_end(struct vmap_area
**pnext
,
2182 struct vmap_area
**pprev
,
2183 unsigned long align
)
2185 const unsigned long vmalloc_end
= VMALLOC_END
& ~(align
- 1);
2189 addr
= min((*pnext
)->va_start
& ~(align
- 1), vmalloc_end
);
2193 while (*pprev
&& (*pprev
)->va_end
> addr
) {
2195 *pprev
= node_to_va(rb_prev(&(*pnext
)->rb_node
));
2202 * pcpu_get_vm_areas - allocate vmalloc areas for percpu allocator
2203 * @offsets: array containing offset of each area
2204 * @sizes: array containing size of each area
2205 * @nr_vms: the number of areas to allocate
2206 * @align: alignment, all entries in @offsets and @sizes must be aligned to this
2208 * Returns: kmalloc'd vm_struct pointer array pointing to allocated
2209 * vm_structs on success, %NULL on failure
2211 * Percpu allocator wants to use congruent vm areas so that it can
2212 * maintain the offsets among percpu areas. This function allocates
2213 * congruent vmalloc areas for it with GFP_KERNEL. These areas tend to
2214 * be scattered pretty far, distance between two areas easily going up
2215 * to gigabytes. To avoid interacting with regular vmallocs, these
2216 * areas are allocated from top.
2218 * Despite its complicated look, this allocator is rather simple. It
2219 * does everything top-down and scans areas from the end looking for
2220 * matching slot. While scanning, if any of the areas overlaps with
2221 * existing vmap_area, the base address is pulled down to fit the
2222 * area. Scanning is repeated till all the areas fit and then all
2223 * necessary data structres are inserted and the result is returned.
2225 struct vm_struct
**pcpu_get_vm_areas(const unsigned long *offsets
,
2226 const size_t *sizes
, int nr_vms
,
2229 const unsigned long vmalloc_start
= ALIGN(VMALLOC_START
, align
);
2230 const unsigned long vmalloc_end
= VMALLOC_END
& ~(align
- 1);
2231 struct vmap_area
**vas
, *prev
, *next
;
2232 struct vm_struct
**vms
;
2233 int area
, area2
, last_area
, term_area
;
2234 unsigned long base
, start
, end
, last_end
;
2235 bool purged
= false;
2237 /* verify parameters and allocate data structures */
2238 BUG_ON(align
& ~PAGE_MASK
|| !is_power_of_2(align
));
2239 for (last_area
= 0, area
= 0; area
< nr_vms
; area
++) {
2240 start
= offsets
[area
];
2241 end
= start
+ sizes
[area
];
2243 /* is everything aligned properly? */
2244 BUG_ON(!IS_ALIGNED(offsets
[area
], align
));
2245 BUG_ON(!IS_ALIGNED(sizes
[area
], align
));
2247 /* detect the area with the highest address */
2248 if (start
> offsets
[last_area
])
2251 for (area2
= 0; area2
< nr_vms
; area2
++) {
2252 unsigned long start2
= offsets
[area2
];
2253 unsigned long end2
= start2
+ sizes
[area2
];
2258 BUG_ON(start2
>= start
&& start2
< end
);
2259 BUG_ON(end2
<= end
&& end2
> start
);
2262 last_end
= offsets
[last_area
] + sizes
[last_area
];
2264 if (vmalloc_end
- vmalloc_start
< last_end
) {
2269 vms
= kzalloc(sizeof(vms
[0]) * nr_vms
, GFP_KERNEL
);
2270 vas
= kzalloc(sizeof(vas
[0]) * nr_vms
, GFP_KERNEL
);
2274 for (area
= 0; area
< nr_vms
; area
++) {
2275 vas
[area
] = kzalloc(sizeof(struct vmap_area
), GFP_KERNEL
);
2276 vms
[area
] = kzalloc(sizeof(struct vm_struct
), GFP_KERNEL
);
2277 if (!vas
[area
] || !vms
[area
])
2281 spin_lock(&vmap_area_lock
);
2283 /* start scanning - we scan from the top, begin with the last area */
2284 area
= term_area
= last_area
;
2285 start
= offsets
[area
];
2286 end
= start
+ sizes
[area
];
2288 if (!pvm_find_next_prev(vmap_area_pcpu_hole
, &next
, &prev
)) {
2289 base
= vmalloc_end
- last_end
;
2292 base
= pvm_determine_end(&next
, &prev
, align
) - end
;
2295 BUG_ON(next
&& next
->va_end
<= base
+ end
);
2296 BUG_ON(prev
&& prev
->va_end
> base
+ end
);
2299 * base might have underflowed, add last_end before
2302 if (base
+ last_end
< vmalloc_start
+ last_end
) {
2303 spin_unlock(&vmap_area_lock
);
2305 purge_vmap_area_lazy();
2313 * If next overlaps, move base downwards so that it's
2314 * right below next and then recheck.
2316 if (next
&& next
->va_start
< base
+ end
) {
2317 base
= pvm_determine_end(&next
, &prev
, align
) - end
;
2323 * If prev overlaps, shift down next and prev and move
2324 * base so that it's right below new next and then
2327 if (prev
&& prev
->va_end
> base
+ start
) {
2329 prev
= node_to_va(rb_prev(&next
->rb_node
));
2330 base
= pvm_determine_end(&next
, &prev
, align
) - end
;
2336 * This area fits, move on to the previous one. If
2337 * the previous one is the terminal one, we're done.
2339 area
= (area
+ nr_vms
- 1) % nr_vms
;
2340 if (area
== term_area
)
2342 start
= offsets
[area
];
2343 end
= start
+ sizes
[area
];
2344 pvm_find_next_prev(base
+ end
, &next
, &prev
);
2347 /* we've found a fitting base, insert all va's */
2348 for (area
= 0; area
< nr_vms
; area
++) {
2349 struct vmap_area
*va
= vas
[area
];
2351 va
->va_start
= base
+ offsets
[area
];
2352 va
->va_end
= va
->va_start
+ sizes
[area
];
2353 __insert_vmap_area(va
);
2356 vmap_area_pcpu_hole
= base
+ offsets
[last_area
];
2358 spin_unlock(&vmap_area_lock
);
2360 /* insert all vm's */
2361 for (area
= 0; area
< nr_vms
; area
++)
2362 insert_vmalloc_vm(vms
[area
], vas
[area
], VM_ALLOC
,
2369 for (area
= 0; area
< nr_vms
; area
++) {
2381 * pcpu_free_vm_areas - free vmalloc areas for percpu allocator
2382 * @vms: vm_struct pointer array returned by pcpu_get_vm_areas()
2383 * @nr_vms: the number of allocated areas
2385 * Free vm_structs and the array allocated by pcpu_get_vm_areas().
2387 void pcpu_free_vm_areas(struct vm_struct
**vms
, int nr_vms
)
2391 for (i
= 0; i
< nr_vms
; i
++)
2392 free_vm_area(vms
[i
]);
2395 #endif /* CONFIG_SMP */
2397 #ifdef CONFIG_PROC_FS
2398 static void *s_start(struct seq_file
*m
, loff_t
*pos
)
2399 __acquires(&vmlist_lock
)
2402 struct vm_struct
*v
;
2404 read_lock(&vmlist_lock
);
2406 while (n
> 0 && v
) {
2417 static void *s_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
2419 struct vm_struct
*v
= p
;
2425 static void s_stop(struct seq_file
*m
, void *p
)
2426 __releases(&vmlist_lock
)
2428 read_unlock(&vmlist_lock
);
2431 static void show_numa_info(struct seq_file
*m
, struct vm_struct
*v
)
2434 unsigned int nr
, *counters
= m
->private;
2439 memset(counters
, 0, nr_node_ids
* sizeof(unsigned int));
2441 for (nr
= 0; nr
< v
->nr_pages
; nr
++)
2442 counters
[page_to_nid(v
->pages
[nr
])]++;
2444 for_each_node_state(nr
, N_HIGH_MEMORY
)
2446 seq_printf(m
, " N%u=%u", nr
, counters
[nr
]);
2450 static int s_show(struct seq_file
*m
, void *p
)
2452 struct vm_struct
*v
= p
;
2454 seq_printf(m
, "0x%p-0x%p %7ld",
2455 v
->addr
, v
->addr
+ v
->size
, v
->size
);
2458 seq_printf(m
, " %pS", v
->caller
);
2461 seq_printf(m
, " pages=%d", v
->nr_pages
);
2464 seq_printf(m
, " phys=%llx", (unsigned long long)v
->phys_addr
);
2466 if (v
->flags
& VM_IOREMAP
)
2467 seq_printf(m
, " ioremap");
2469 if (v
->flags
& VM_ALLOC
)
2470 seq_printf(m
, " vmalloc");
2472 if (v
->flags
& VM_MAP
)
2473 seq_printf(m
, " vmap");
2475 if (v
->flags
& VM_USERMAP
)
2476 seq_printf(m
, " user");
2478 if (v
->flags
& VM_VPAGES
)
2479 seq_printf(m
, " vpages");
2481 show_numa_info(m
, v
);
2486 static const struct seq_operations vmalloc_op
= {
2493 static int vmalloc_open(struct inode
*inode
, struct file
*file
)
2495 unsigned int *ptr
= NULL
;
2499 ptr
= kmalloc(nr_node_ids
* sizeof(unsigned int), GFP_KERNEL
);
2503 ret
= seq_open(file
, &vmalloc_op
);
2505 struct seq_file
*m
= file
->private_data
;
2512 static const struct file_operations proc_vmalloc_operations
= {
2513 .open
= vmalloc_open
,
2515 .llseek
= seq_lseek
,
2516 .release
= seq_release_private
,
2519 static int __init
proc_vmalloc_init(void)
2521 proc_create("vmallocinfo", S_IRUSR
, NULL
, &proc_vmalloc_operations
);
2524 module_init(proc_vmalloc_init
);