projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 932b18e0 AA |
1 | /* |
| 2 | * include/linux/userfaultfd_k.h | |
| 3 | * | |
| 4 | * Copyright (C) 2015 Red Hat, Inc. | |
| 5 | * | |
| 6 | */ | |
| 7 | ||
| 8 | #ifndef _LINUX_USERFAULTFD_K_H | |
| 9 | #define _LINUX_USERFAULTFD_K_H | |
| 10 | ||
| 11 | #ifdef CONFIG_USERFAULTFD | |
| 12 | ||
| 13 | #include <linux/userfaultfd.h> /* linux/include/uapi/linux/userfaultfd.h */ | |
| 14 | ||
| 15 | #include <linux/fcntl.h> | |
| 16 | ||
| 17 | /* | |
| 18 | * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining | |
| 19 | * new flags, since they might collide with O_* ones. We want | |
| 20 | * to re-use O_* flags that couldn't possibly have a meaning | |
| 21 | * from userfaultfd, in order to leave a free define-space for | |
| 22 | * shared O_* flags. | |
| 23 | */ | |
| 24 | #define UFFD_CLOEXEC O_CLOEXEC | |
| 25 | #define UFFD_NONBLOCK O_NONBLOCK | |
| 26 | ||
| 27 | #define UFFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK) | |
| 28 | #define UFFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS) | |
| 29 | ||
| bae473a4 | 30 | extern int handle_userfault(struct fault_env *fe, unsigned long reason); |
| 932b18e0 | 31 | |
| c1a4de99 AA |
32 | extern ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start, |
| 33 | unsigned long src_start, unsigned long len); | |
| 34 | extern ssize_t mfill_zeropage(struct mm_struct *dst_mm, | |
| 35 | unsigned long dst_start, | |
| 36 | unsigned long len); | |
| 37 | ||
| 932b18e0 AA |
38 | /* mm helpers */ |
| 39 | static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, | |
| 40 | struct vm_userfaultfd_ctx vm_ctx) | |
| 41 | { | |
| 42 | return vma->vm_userfaultfd_ctx.ctx == vm_ctx.ctx; | |
| 43 | } | |
| 44 | ||
| 45 | static inline bool userfaultfd_missing(struct vm_area_struct *vma) | |
| 46 | { | |
| 47 | return vma->vm_flags & VM_UFFD_MISSING; | |
| 48 | } | |
| 49 | ||
| 50 | static inline bool userfaultfd_armed(struct vm_area_struct *vma) | |
| 51 | { | |
| 52 | return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP); | |
| 53 | } | |
| 54 | ||
| 55 | #else /* CONFIG_USERFAULTFD */ | |
| 56 | ||
| 57 | /* mm helpers */ | |
| bae473a4 | 58 | static inline int handle_userfault(struct fault_env *fe, unsigned long reason) |
| 932b18e0 AA |
59 | { |
| 60 | return VM_FAULT_SIGBUS; | |
| 61 | } | |
| 62 | ||
| 63 | static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, | |
| 64 | struct vm_userfaultfd_ctx vm_ctx) | |
| 65 | { | |
| 66 | return true; | |
| 67 | } | |
| 68 | ||
| 69 | static inline bool userfaultfd_missing(struct vm_area_struct *vma) | |
| 70 | { | |
| 71 | return false; | |
| 72 | } | |
| 73 | ||
| 74 | static inline bool userfaultfd_armed(struct vm_area_struct *vma) | |
| 75 | { | |
| 76 | return false; | |
| 77 | } | |
| 78 | ||
| 79 | #endif /* CONFIG_USERFAULTFD */ | |
| 80 | ||
| 81 | #endif /* _LINUX_USERFAULTFD_K_H */ |