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
12 #include <linux/module.h>
13 #include <linux/highmem.h>
14 #include <linux/slab.h>
15 #include <linux/spinlock.h>
16 #include <linux/interrupt.h>
18 #include <linux/vmalloc.h>
20 #include <asm/uaccess.h>
21 #include <asm/tlbflush.h>
24 DEFINE_RWLOCK(vmlist_lock
);
25 struct vm_struct
*vmlist
;
27 static void *__vmalloc_node(unsigned long size
, gfp_t gfp_mask
, pgprot_t prot
,
30 static void vunmap_pte_range(pmd_t
*pmd
, unsigned long addr
, unsigned long end
)
34 pte
= pte_offset_kernel(pmd
, addr
);
36 pte_t ptent
= ptep_get_and_clear(&init_mm
, addr
, pte
);
37 WARN_ON(!pte_none(ptent
) && !pte_present(ptent
));
38 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
41 static inline void vunmap_pmd_range(pud_t
*pud
, unsigned long addr
,
47 pmd
= pmd_offset(pud
, addr
);
49 next
= pmd_addr_end(addr
, end
);
50 if (pmd_none_or_clear_bad(pmd
))
52 vunmap_pte_range(pmd
, addr
, next
);
53 } while (pmd
++, addr
= next
, addr
!= end
);
56 static inline void vunmap_pud_range(pgd_t
*pgd
, unsigned long addr
,
62 pud
= pud_offset(pgd
, addr
);
64 next
= pud_addr_end(addr
, end
);
65 if (pud_none_or_clear_bad(pud
))
67 vunmap_pmd_range(pud
, addr
, next
);
68 } while (pud
++, addr
= next
, addr
!= end
);
71 void unmap_kernel_range(unsigned long addr
, unsigned long size
)
75 unsigned long start
= addr
;
76 unsigned long end
= addr
+ size
;
79 pgd
= pgd_offset_k(addr
);
80 flush_cache_vunmap(addr
, end
);
82 next
= pgd_addr_end(addr
, end
);
83 if (pgd_none_or_clear_bad(pgd
))
85 vunmap_pud_range(pgd
, addr
, next
);
86 } while (pgd
++, addr
= next
, addr
!= end
);
87 flush_tlb_kernel_range(start
, end
);
90 static void unmap_vm_area(struct vm_struct
*area
)
92 unmap_kernel_range((unsigned long)area
->addr
, area
->size
);
95 static int vmap_pte_range(pmd_t
*pmd
, unsigned long addr
,
96 unsigned long end
, pgprot_t prot
, struct page
***pages
)
100 pte
= pte_alloc_kernel(pmd
, addr
);
104 struct page
*page
= **pages
;
105 WARN_ON(!pte_none(*pte
));
108 set_pte_at(&init_mm
, addr
, pte
, mk_pte(page
, prot
));
110 } while (pte
++, addr
+= PAGE_SIZE
, addr
!= end
);
114 static inline int vmap_pmd_range(pud_t
*pud
, unsigned long addr
,
115 unsigned long end
, pgprot_t prot
, struct page
***pages
)
120 pmd
= pmd_alloc(&init_mm
, pud
, addr
);
124 next
= pmd_addr_end(addr
, end
);
125 if (vmap_pte_range(pmd
, addr
, next
, prot
, pages
))
127 } while (pmd
++, addr
= next
, addr
!= end
);
131 static inline int vmap_pud_range(pgd_t
*pgd
, unsigned long addr
,
132 unsigned long end
, pgprot_t prot
, struct page
***pages
)
137 pud
= pud_alloc(&init_mm
, pgd
, addr
);
141 next
= pud_addr_end(addr
, end
);
142 if (vmap_pmd_range(pud
, addr
, next
, prot
, pages
))
144 } while (pud
++, addr
= next
, addr
!= end
);
148 int map_vm_area(struct vm_struct
*area
, pgprot_t prot
, struct page
***pages
)
152 unsigned long addr
= (unsigned long) area
->addr
;
153 unsigned long end
= addr
+ area
->size
- PAGE_SIZE
;
157 pgd
= pgd_offset_k(addr
);
159 next
= pgd_addr_end(addr
, end
);
160 err
= vmap_pud_range(pgd
, addr
, next
, prot
, pages
);
163 } while (pgd
++, addr
= next
, addr
!= end
);
164 flush_cache_vmap((unsigned long) area
->addr
, end
);
167 EXPORT_SYMBOL_GPL(map_vm_area
);
169 static struct vm_struct
*__get_vm_area_node(unsigned long size
, unsigned long flags
,
170 unsigned long start
, unsigned long end
,
171 int node
, gfp_t gfp_mask
)
173 struct vm_struct
**p
, *tmp
, *area
;
174 unsigned long align
= 1;
177 BUG_ON(in_interrupt());
178 if (flags
& VM_IOREMAP
) {
181 if (bit
> IOREMAP_MAX_ORDER
)
182 bit
= IOREMAP_MAX_ORDER
;
183 else if (bit
< PAGE_SHIFT
)
188 addr
= ALIGN(start
, align
);
189 size
= PAGE_ALIGN(size
);
193 area
= kmalloc_node(sizeof(*area
), gfp_mask
& GFP_RECLAIM_MASK
, node
);
199 * We always allocate a guard page.
203 write_lock(&vmlist_lock
);
204 for (p
= &vmlist
; (tmp
= *p
) != NULL
;p
= &tmp
->next
) {
205 if ((unsigned long)tmp
->addr
< addr
) {
206 if((unsigned long)tmp
->addr
+ tmp
->size
>= addr
)
207 addr
= ALIGN(tmp
->size
+
208 (unsigned long)tmp
->addr
, align
);
211 if ((size
+ addr
) < addr
)
213 if (size
+ addr
<= (unsigned long)tmp
->addr
)
215 addr
= ALIGN(tmp
->size
+ (unsigned long)tmp
->addr
, align
);
216 if (addr
> end
- size
)
225 area
->addr
= (void *)addr
;
230 write_unlock(&vmlist_lock
);
235 write_unlock(&vmlist_lock
);
237 if (printk_ratelimit())
238 printk(KERN_WARNING
"allocation failed: out of vmalloc space - use vmalloc=<size> to increase size.\n");
242 struct vm_struct
*__get_vm_area(unsigned long size
, unsigned long flags
,
243 unsigned long start
, unsigned long end
)
245 return __get_vm_area_node(size
, flags
, start
, end
, -1, GFP_KERNEL
);
247 EXPORT_SYMBOL_GPL(__get_vm_area
);
250 * get_vm_area - reserve a contingous kernel virtual area
251 * @size: size of the area
252 * @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
254 * Search an area of @size in the kernel virtual mapping area,
255 * and reserved it for out purposes. Returns the area descriptor
256 * on success or %NULL on failure.
258 struct vm_struct
*get_vm_area(unsigned long size
, unsigned long flags
)
260 return __get_vm_area(size
, flags
, VMALLOC_START
, VMALLOC_END
);
263 struct vm_struct
*get_vm_area_node(unsigned long size
, unsigned long flags
,
264 int node
, gfp_t gfp_mask
)
266 return __get_vm_area_node(size
, flags
, VMALLOC_START
, VMALLOC_END
, node
,
270 /* Caller must hold vmlist_lock */
271 static struct vm_struct
*__find_vm_area(void *addr
)
273 struct vm_struct
*tmp
;
275 for (tmp
= vmlist
; tmp
!= NULL
; tmp
= tmp
->next
) {
276 if (tmp
->addr
== addr
)
283 /* Caller must hold vmlist_lock */
284 static struct vm_struct
*__remove_vm_area(void *addr
)
286 struct vm_struct
**p
, *tmp
;
288 for (p
= &vmlist
; (tmp
= *p
) != NULL
;p
= &tmp
->next
) {
289 if (tmp
->addr
== addr
)
299 * Remove the guard page.
301 tmp
->size
-= PAGE_SIZE
;
306 * remove_vm_area - find and remove a contingous kernel virtual area
307 * @addr: base address
309 * Search for the kernel VM area starting at @addr, and remove it.
310 * This function returns the found VM area, but using it is NOT safe
311 * on SMP machines, except for its size or flags.
313 struct vm_struct
*remove_vm_area(void *addr
)
316 write_lock(&vmlist_lock
);
317 v
= __remove_vm_area(addr
);
318 write_unlock(&vmlist_lock
);
322 static void __vunmap(void *addr
, int deallocate_pages
)
324 struct vm_struct
*area
;
329 if ((PAGE_SIZE
-1) & (unsigned long)addr
) {
330 printk(KERN_ERR
"Trying to vfree() bad address (%p)\n", addr
);
335 area
= remove_vm_area(addr
);
336 if (unlikely(!area
)) {
337 printk(KERN_ERR
"Trying to vfree() nonexistent vm area (%p)\n",
343 debug_check_no_locks_freed(addr
, area
->size
);
345 if (deallocate_pages
) {
348 for (i
= 0; i
< area
->nr_pages
; i
++) {
349 BUG_ON(!area
->pages
[i
]);
350 __free_page(area
->pages
[i
]);
353 if (area
->flags
& VM_VPAGES
)
364 * vfree - release memory allocated by vmalloc()
365 * @addr: memory base address
367 * Free the virtually contiguous memory area starting at @addr, as
368 * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
369 * NULL, no operation is performed.
371 * Must not be called in interrupt context.
373 void vfree(void *addr
)
375 BUG_ON(in_interrupt());
378 EXPORT_SYMBOL(vfree
);
381 * vunmap - release virtual mapping obtained by vmap()
382 * @addr: memory base address
384 * Free the virtually contiguous memory area starting at @addr,
385 * which was created from the page array passed to vmap().
387 * Must not be called in interrupt context.
389 void vunmap(void *addr
)
391 BUG_ON(in_interrupt());
394 EXPORT_SYMBOL(vunmap
);
397 * vmap - map an array of pages into virtually contiguous space
398 * @pages: array of page pointers
399 * @count: number of pages to map
400 * @flags: vm_area->flags
401 * @prot: page protection for the mapping
403 * Maps @count pages from @pages into contiguous kernel virtual
406 void *vmap(struct page
**pages
, unsigned int count
,
407 unsigned long flags
, pgprot_t prot
)
409 struct vm_struct
*area
;
411 if (count
> num_physpages
)
414 area
= get_vm_area((count
<< PAGE_SHIFT
), flags
);
417 if (map_vm_area(area
, prot
, &pages
)) {
426 void *__vmalloc_area_node(struct vm_struct
*area
, gfp_t gfp_mask
,
427 pgprot_t prot
, int node
)
430 unsigned int nr_pages
, array_size
, i
;
432 nr_pages
= (area
->size
- PAGE_SIZE
) >> PAGE_SHIFT
;
433 array_size
= (nr_pages
* sizeof(struct page
*));
435 area
->nr_pages
= nr_pages
;
436 /* Please note that the recursion is strictly bounded. */
437 if (array_size
> PAGE_SIZE
) {
438 pages
= __vmalloc_node(array_size
, gfp_mask
| __GFP_ZERO
,
440 area
->flags
|= VM_VPAGES
;
442 pages
= kmalloc_node(array_size
,
443 (gfp_mask
& GFP_RECLAIM_MASK
) | __GFP_ZERO
,
448 remove_vm_area(area
->addr
);
453 for (i
= 0; i
< area
->nr_pages
; i
++) {
455 area
->pages
[i
] = alloc_page(gfp_mask
);
457 area
->pages
[i
] = alloc_pages_node(node
, gfp_mask
, 0);
458 if (unlikely(!area
->pages
[i
])) {
459 /* Successfully allocated i pages, free them in __vunmap() */
465 if (map_vm_area(area
, prot
, &pages
))
474 void *__vmalloc_area(struct vm_struct
*area
, gfp_t gfp_mask
, pgprot_t prot
)
476 return __vmalloc_area_node(area
, gfp_mask
, prot
, -1);
480 * __vmalloc_node - allocate virtually contiguous memory
481 * @size: allocation size
482 * @gfp_mask: flags for the page level allocator
483 * @prot: protection mask for the allocated pages
484 * @node: node to use for allocation or -1
486 * Allocate enough pages to cover @size from the page level
487 * allocator with @gfp_mask flags. Map them into contiguous
488 * kernel virtual space, using a pagetable protection of @prot.
490 static void *__vmalloc_node(unsigned long size
, gfp_t gfp_mask
, pgprot_t prot
,
493 struct vm_struct
*area
;
495 size
= PAGE_ALIGN(size
);
496 if (!size
|| (size
>> PAGE_SHIFT
) > num_physpages
)
499 area
= get_vm_area_node(size
, VM_ALLOC
, node
, gfp_mask
);
503 return __vmalloc_area_node(area
, gfp_mask
, prot
, node
);
506 void *__vmalloc(unsigned long size
, gfp_t gfp_mask
, pgprot_t prot
)
508 return __vmalloc_node(size
, gfp_mask
, prot
, -1);
510 EXPORT_SYMBOL(__vmalloc
);
513 * vmalloc - allocate virtually contiguous memory
514 * @size: allocation size
515 * Allocate enough pages to cover @size from the page level
516 * allocator and map them into contiguous kernel virtual space.
518 * For tight control over page level allocator and protection flags
519 * use __vmalloc() instead.
521 void *vmalloc(unsigned long size
)
523 return __vmalloc(size
, GFP_KERNEL
| __GFP_HIGHMEM
, PAGE_KERNEL
);
525 EXPORT_SYMBOL(vmalloc
);
528 * vmalloc_user - allocate zeroed virtually contiguous memory for userspace
529 * @size: allocation size
531 * The resulting memory area is zeroed so it can be mapped to userspace
532 * without leaking data.
534 void *vmalloc_user(unsigned long size
)
536 struct vm_struct
*area
;
539 ret
= __vmalloc(size
, GFP_KERNEL
| __GFP_HIGHMEM
| __GFP_ZERO
, PAGE_KERNEL
);
541 write_lock(&vmlist_lock
);
542 area
= __find_vm_area(ret
);
543 area
->flags
|= VM_USERMAP
;
544 write_unlock(&vmlist_lock
);
548 EXPORT_SYMBOL(vmalloc_user
);
551 * vmalloc_node - allocate memory on a specific node
552 * @size: allocation size
555 * Allocate enough pages to cover @size from the page level
556 * allocator and map them into contiguous kernel virtual space.
558 * For tight control over page level allocator and protection flags
559 * use __vmalloc() instead.
561 void *vmalloc_node(unsigned long size
, int node
)
563 return __vmalloc_node(size
, GFP_KERNEL
| __GFP_HIGHMEM
, PAGE_KERNEL
, node
);
565 EXPORT_SYMBOL(vmalloc_node
);
567 #ifndef PAGE_KERNEL_EXEC
568 # define PAGE_KERNEL_EXEC PAGE_KERNEL
572 * vmalloc_exec - allocate virtually contiguous, executable memory
573 * @size: allocation size
575 * Kernel-internal function to allocate enough pages to cover @size
576 * the page level allocator and map them into contiguous and
577 * executable kernel virtual space.
579 * For tight control over page level allocator and protection flags
580 * use __vmalloc() instead.
583 void *vmalloc_exec(unsigned long size
)
585 return __vmalloc(size
, GFP_KERNEL
| __GFP_HIGHMEM
, PAGE_KERNEL_EXEC
);
588 #if defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA32)
589 #define GFP_VMALLOC32 GFP_DMA32 | GFP_KERNEL
590 #elif defined(CONFIG_64BIT) && defined(CONFIG_ZONE_DMA)
591 #define GFP_VMALLOC32 GFP_DMA | GFP_KERNEL
593 #define GFP_VMALLOC32 GFP_KERNEL
597 * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
598 * @size: allocation size
600 * Allocate enough 32bit PA addressable pages to cover @size from the
601 * page level allocator and map them into contiguous kernel virtual space.
603 void *vmalloc_32(unsigned long size
)
605 return __vmalloc(size
, GFP_VMALLOC32
, PAGE_KERNEL
);
607 EXPORT_SYMBOL(vmalloc_32
);
610 * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
611 * @size: allocation size
613 * The resulting memory area is 32bit addressable and zeroed so it can be
614 * mapped to userspace without leaking data.
616 void *vmalloc_32_user(unsigned long size
)
618 struct vm_struct
*area
;
621 ret
= __vmalloc(size
, GFP_VMALLOC32
| __GFP_ZERO
, PAGE_KERNEL
);
623 write_lock(&vmlist_lock
);
624 area
= __find_vm_area(ret
);
625 area
->flags
|= VM_USERMAP
;
626 write_unlock(&vmlist_lock
);
630 EXPORT_SYMBOL(vmalloc_32_user
);
632 long vread(char *buf
, char *addr
, unsigned long count
)
634 struct vm_struct
*tmp
;
635 char *vaddr
, *buf_start
= buf
;
638 /* Don't allow overflow */
639 if ((unsigned long) addr
+ count
< count
)
640 count
= -(unsigned long) addr
;
642 read_lock(&vmlist_lock
);
643 for (tmp
= vmlist
; tmp
; tmp
= tmp
->next
) {
644 vaddr
= (char *) tmp
->addr
;
645 if (addr
>= vaddr
+ tmp
->size
- PAGE_SIZE
)
647 while (addr
< vaddr
) {
655 n
= vaddr
+ tmp
->size
- PAGE_SIZE
- addr
;
666 read_unlock(&vmlist_lock
);
667 return buf
- buf_start
;
670 long vwrite(char *buf
, char *addr
, unsigned long count
)
672 struct vm_struct
*tmp
;
673 char *vaddr
, *buf_start
= buf
;
676 /* Don't allow overflow */
677 if ((unsigned long) addr
+ count
< count
)
678 count
= -(unsigned long) addr
;
680 read_lock(&vmlist_lock
);
681 for (tmp
= vmlist
; tmp
; tmp
= tmp
->next
) {
682 vaddr
= (char *) tmp
->addr
;
683 if (addr
>= vaddr
+ tmp
->size
- PAGE_SIZE
)
685 while (addr
< vaddr
) {
692 n
= vaddr
+ tmp
->size
- PAGE_SIZE
- addr
;
703 read_unlock(&vmlist_lock
);
704 return buf
- buf_start
;
708 * remap_vmalloc_range - map vmalloc pages to userspace
709 * @vma: vma to cover (map full range of vma)
710 * @addr: vmalloc memory
711 * @pgoff: number of pages into addr before first page to map
712 * @returns: 0 for success, -Exxx on failure
714 * This function checks that addr is a valid vmalloc'ed area, and
715 * that it is big enough to cover the vma. Will return failure if
716 * that criteria isn't met.
718 * Similar to remap_pfn_range() (see mm/memory.c)
720 int remap_vmalloc_range(struct vm_area_struct
*vma
, void *addr
,
723 struct vm_struct
*area
;
724 unsigned long uaddr
= vma
->vm_start
;
725 unsigned long usize
= vma
->vm_end
- vma
->vm_start
;
728 if ((PAGE_SIZE
-1) & (unsigned long)addr
)
731 read_lock(&vmlist_lock
);
732 area
= __find_vm_area(addr
);
734 goto out_einval_locked
;
736 if (!(area
->flags
& VM_USERMAP
))
737 goto out_einval_locked
;
739 if (usize
+ (pgoff
<< PAGE_SHIFT
) > area
->size
- PAGE_SIZE
)
740 goto out_einval_locked
;
741 read_unlock(&vmlist_lock
);
743 addr
+= pgoff
<< PAGE_SHIFT
;
745 struct page
*page
= vmalloc_to_page(addr
);
746 ret
= vm_insert_page(vma
, uaddr
, page
);
755 /* Prevent "things" like memory migration? VM_flags need a cleanup... */
756 vma
->vm_flags
|= VM_RESERVED
;
761 read_unlock(&vmlist_lock
);
764 EXPORT_SYMBOL(remap_vmalloc_range
);
767 * Implement a stub for vmalloc_sync_all() if the architecture chose not to
770 void __attribute__((weak
)) vmalloc_sync_all(void)
775 static int f(pte_t
*pte
, struct page
*pmd_page
, unsigned long addr
, void *data
)
777 /* apply_to_page_range() does all the hard work. */
782 * alloc_vm_area - allocate a range of kernel address space
783 * @size: size of the area
784 * @returns: NULL on failure, vm_struct on success
786 * This function reserves a range of kernel address space, and
787 * allocates pagetables to map that range. No actual mappings
788 * are created. If the kernel address space is not shared
789 * between processes, it syncs the pagetable across all
792 struct vm_struct
*alloc_vm_area(size_t size
)
794 struct vm_struct
*area
;
796 area
= get_vm_area(size
, VM_IOREMAP
);
801 * This ensures that page tables are constructed for this region
802 * of kernel virtual address space and mapped into init_mm.
804 if (apply_to_page_range(&init_mm
, (unsigned long)area
->addr
,
805 area
->size
, f
, NULL
)) {
810 /* Make sure the pagetables are constructed in process kernel
816 EXPORT_SYMBOL_GPL(alloc_vm_area
);
818 void free_vm_area(struct vm_struct
*area
)
820 struct vm_struct
*ret
;
821 ret
= remove_vm_area(area
->addr
);
825 EXPORT_SYMBOL_GPL(free_vm_area
);
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