82 lines
2.0 KiB
C
82 lines
2.0 KiB
C
/*
|
|
* include/linux/userfaultfd_k.h
|
|
*
|
|
* Copyright (C) 2015 Red Hat, Inc.
|
|
*
|
|
*/
|
|
|
|
#ifndef _LINUX_USERFAULTFD_K_H
|
|
#define _LINUX_USERFAULTFD_K_H
|
|
|
|
#ifdef CONFIG_USERFAULTFD
|
|
|
|
#include <linux/userfaultfd.h> /* linux/include/uapi/linux/userfaultfd.h */
|
|
|
|
#include <linux/fcntl.h>
|
|
|
|
/*
|
|
* CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
|
|
* new flags, since they might collide with O_* ones. We want
|
|
* to re-use O_* flags that couldn't possibly have a meaning
|
|
* from userfaultfd, in order to leave a free define-space for
|
|
* shared O_* flags.
|
|
*/
|
|
#define UFFD_CLOEXEC O_CLOEXEC
|
|
#define UFFD_NONBLOCK O_NONBLOCK
|
|
|
|
#define UFFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
|
|
#define UFFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS)
|
|
|
|
extern int handle_userfault(struct vm_fault *vmf, unsigned long reason);
|
|
|
|
extern ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start,
|
|
unsigned long src_start, unsigned long len);
|
|
extern ssize_t mfill_zeropage(struct mm_struct *dst_mm,
|
|
unsigned long dst_start,
|
|
unsigned long len);
|
|
|
|
/* mm helpers */
|
|
static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma,
|
|
struct vm_userfaultfd_ctx vm_ctx)
|
|
{
|
|
return vma->vm_userfaultfd_ctx.ctx == vm_ctx.ctx;
|
|
}
|
|
|
|
static inline bool userfaultfd_missing(struct vm_area_struct *vma)
|
|
{
|
|
return vma->vm_flags & VM_UFFD_MISSING;
|
|
}
|
|
|
|
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
|
|
{
|
|
return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP);
|
|
}
|
|
|
|
#else /* CONFIG_USERFAULTFD */
|
|
|
|
/* mm helpers */
|
|
static inline int handle_userfault(struct vm_fault *vmf, unsigned long reason)
|
|
{
|
|
return VM_FAULT_SIGBUS;
|
|
}
|
|
|
|
static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma,
|
|
struct vm_userfaultfd_ctx vm_ctx)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline bool userfaultfd_missing(struct vm_area_struct *vma)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
static inline bool userfaultfd_armed(struct vm_area_struct *vma)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* CONFIG_USERFAULTFD */
|
|
|
|
#endif /* _LINUX_USERFAULTFD_K_H */
|