linux-stable/include/linux/userfaultfd_k.h
Mike Rapoport d811914d87 userfaultfd: non-cooperative: rename *EVENT_MADVDONTNEED to *EVENT_REMOVE
Patch series "userfaultfd: non-cooperative: add madvise() event for
MADV_REMOVE request".

These patches add notification of madvise(MADV_REMOVE) event to
non-cooperative userfaultfd monitor.

The first pacth renames EVENT_MADVDONTNEED to EVENT_REMOVE along with
relevant functions and structures.  Using _REMOVE instead of
_MADVDONTNEED describes the event semantics more clearly and I hope it's
not too late for such change in the ABI.

This patch (of 3):

The UFFD_EVENT_MADVDONTNEED purpose is to notify uffd monitor about
removal of certain range from address space tracked by userfaultfd.
Hence, UFFD_EVENT_REMOVE seems to better reflect the operation
semantics.  Respectively, 'madv_dn' field of uffd_msg is renamed to
'remove' and the madvise_userfault_dontneed callback is renamed to
userfaultfd_remove.

Link: http://lkml.kernel.org/r/1484814154-1557-2-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00

123 lines
3.1 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);
}
extern int dup_userfaultfd(struct vm_area_struct *, struct list_head *);
extern void dup_userfaultfd_complete(struct list_head *);
extern void mremap_userfaultfd_prep(struct vm_area_struct *,
struct vm_userfaultfd_ctx *);
extern void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx *,
unsigned long from, unsigned long to,
unsigned long len);
extern void userfaultfd_remove(struct vm_area_struct *vma,
struct vm_area_struct **prev,
unsigned long start,
unsigned long end);
#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;
}
static inline int dup_userfaultfd(struct vm_area_struct *vma,
struct list_head *l)
{
return 0;
}
static inline void dup_userfaultfd_complete(struct list_head *l)
{
}
static inline void mremap_userfaultfd_prep(struct vm_area_struct *vma,
struct vm_userfaultfd_ctx *ctx)
{
}
static inline void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx *ctx,
unsigned long from,
unsigned long to,
unsigned long len)
{
}
static inline void userfaultfd_remove(struct vm_area_struct *vma,
struct vm_area_struct **prev,
unsigned long start,
unsigned long end)
{
}
#endif /* CONFIG_USERFAULTFD */
#endif /* _LINUX_USERFAULTFD_K_H */