![Souptick Joarder](/assets/img/avatar_default.png)
Use new return type vm_fault_t for fault handler. For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno. Once all instances are converted, vm_fault_t will become a
distinct type.
Ref-> commit 1c8f422059
("mm: change return type to vm_fault_t")
The aim is to change the return type of finish_fault() and
handle_mm_fault() to vm_fault_t type. As part of that clean up return
type of all other recursively called functions have been changed to
vm_fault_t type.
The places from where handle_mm_fault() is getting invoked will be
change to vm_fault_t type but in a separate patch.
vmf_error() is the newly introduce inline function in 4.17-rc6.
[akpm@linux-foundation.org: don't shadow outer local `ret' in __do_huge_pmd_anonymous_page()]
Link: http://lkml.kernel.org/r/20180604171727.GA20279@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
146 lines
3.6 KiB
C
146 lines
3.6 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* 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 vm_fault_t 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,
|
|
bool *mmap_changing);
|
|
extern ssize_t mfill_zeropage(struct mm_struct *dst_mm,
|
|
unsigned long dst_start,
|
|
unsigned long len,
|
|
bool *mmap_changing);
|
|
|
|
/* 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 bool userfaultfd_remove(struct vm_area_struct *vma,
|
|
unsigned long start,
|
|
unsigned long end);
|
|
|
|
extern int userfaultfd_unmap_prep(struct vm_area_struct *vma,
|
|
unsigned long start, unsigned long end,
|
|
struct list_head *uf);
|
|
extern void userfaultfd_unmap_complete(struct mm_struct *mm,
|
|
struct list_head *uf);
|
|
|
|
#else /* CONFIG_USERFAULTFD */
|
|
|
|
/* mm helpers */
|
|
static inline vm_fault_t 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 bool userfaultfd_remove(struct vm_area_struct *vma,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static inline int userfaultfd_unmap_prep(struct vm_area_struct *vma,
|
|
unsigned long start, unsigned long end,
|
|
struct list_head *uf)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void userfaultfd_unmap_complete(struct mm_struct *mm,
|
|
struct list_head *uf)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_USERFAULTFD */
|
|
|
|
#endif /* _LINUX_USERFAULTFD_K_H */
|