forked from mirrors/linux
9585116ba0
get_vm_area always returns an area with an adjacent guard page. That guard page is included in vm_struct.size. iounmap uses vm_struct.size to determine how much address space needs to have change_page_attr applied to it, which will BUG if applied to the guard page. This patch adds a helper function - get_vm_area_size() in linux/vmalloc.h - to return the actual size of a vm area, and uses it to make iounmap do the right thing. There are probably other places which should be using get_vm_area_size(). Thanks to Dave Young <hidave.darkstar@gmail.com> for debugging the problem. [ Andi, it wasn't clear to me whether x86_64 needs the same fix. ] Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Dave Young <hidave.darkstar@gmail.com> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
90 lines
2.7 KiB
C
90 lines
2.7 KiB
C
#ifndef _LINUX_VMALLOC_H
|
|
#define _LINUX_VMALLOC_H
|
|
|
|
#include <linux/spinlock.h>
|
|
#include <asm/page.h> /* pgprot_t */
|
|
|
|
struct vm_area_struct;
|
|
|
|
/* bits in vm_struct->flags */
|
|
#define VM_IOREMAP 0x00000001 /* ioremap() and friends */
|
|
#define VM_ALLOC 0x00000002 /* vmalloc() */
|
|
#define VM_MAP 0x00000004 /* vmap()ed pages */
|
|
#define VM_USERMAP 0x00000008 /* suitable for remap_vmalloc_range */
|
|
#define VM_VPAGES 0x00000010 /* buffer for pages was vmalloc'ed */
|
|
/* bits [20..32] reserved for arch specific ioremap internals */
|
|
|
|
/*
|
|
* Maximum alignment for ioremap() regions.
|
|
* Can be overriden by arch-specific value.
|
|
*/
|
|
#ifndef IOREMAP_MAX_ORDER
|
|
#define IOREMAP_MAX_ORDER (7 + PAGE_SHIFT) /* 128 pages */
|
|
#endif
|
|
|
|
struct vm_struct {
|
|
/* keep next,addr,size together to speedup lookups */
|
|
struct vm_struct *next;
|
|
void *addr;
|
|
unsigned long size;
|
|
unsigned long flags;
|
|
struct page **pages;
|
|
unsigned int nr_pages;
|
|
unsigned long phys_addr;
|
|
};
|
|
|
|
/*
|
|
* Highlevel APIs for driver use
|
|
*/
|
|
extern void *vmalloc(unsigned long size);
|
|
extern void *vmalloc_user(unsigned long size);
|
|
extern void *vmalloc_node(unsigned long size, int node);
|
|
extern void *vmalloc_exec(unsigned long size);
|
|
extern void *vmalloc_32(unsigned long size);
|
|
extern void *vmalloc_32_user(unsigned long size);
|
|
extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot);
|
|
extern void *__vmalloc_area(struct vm_struct *area, gfp_t gfp_mask,
|
|
pgprot_t prot);
|
|
extern void vfree(void *addr);
|
|
|
|
extern void *vmap(struct page **pages, unsigned int count,
|
|
unsigned long flags, pgprot_t prot);
|
|
extern void vunmap(void *addr);
|
|
|
|
extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
|
|
unsigned long pgoff);
|
|
void vmalloc_sync_all(void);
|
|
|
|
/*
|
|
* Lowlevel-APIs (not for driver use!)
|
|
*/
|
|
|
|
static inline size_t get_vm_area_size(const struct vm_struct *area)
|
|
{
|
|
/* return actual size without guard page */
|
|
return area->size - PAGE_SIZE;
|
|
}
|
|
|
|
extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
|
|
extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags,
|
|
unsigned long start, unsigned long end);
|
|
extern struct vm_struct *get_vm_area_node(unsigned long size,
|
|
unsigned long flags, int node,
|
|
gfp_t gfp_mask);
|
|
extern struct vm_struct *remove_vm_area(void *addr);
|
|
|
|
extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
|
|
struct page ***pages);
|
|
extern void unmap_kernel_range(unsigned long addr, unsigned long size);
|
|
|
|
/* Allocate/destroy a 'vmalloc' VM area. */
|
|
extern struct vm_struct *alloc_vm_area(size_t size);
|
|
extern void free_vm_area(struct vm_struct *area);
|
|
|
|
/*
|
|
* Internals. Dont't use..
|
|
*/
|
|
extern rwlock_t vmlist_lock;
|
|
extern struct vm_struct *vmlist;
|
|
|
|
#endif /* _LINUX_VMALLOC_H */
|