projects / linux-2.6-block.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 | ||
| 30 | extern int handle_userfault(struct vm_area_struct *vma, unsigned long address, | |
| 31 | unsigned int flags, unsigned long reason); | |
| 32 | ||
| 33 | /* mm helpers */ | |
| 34 | static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, | |
| 35 | struct vm_userfaultfd_ctx vm_ctx) | |
| 36 | { | |
| 37 | return vma->vm_userfaultfd_ctx.ctx == vm_ctx.ctx; | |
| 38 | } | |
| 39 | ||
| 40 | static inline bool userfaultfd_missing(struct vm_area_struct *vma) | |
| 41 | { | |
| 42 | return vma->vm_flags & VM_UFFD_MISSING; | |
| 43 | } | |
| 44 | ||
| 45 | static inline bool userfaultfd_armed(struct vm_area_struct *vma) | |
| 46 | { | |
| 47 | return vma->vm_flags & (VM_UFFD_MISSING | VM_UFFD_WP); | |
| 48 | } | |
| 49 | ||
| 50 | #else /* CONFIG_USERFAULTFD */ | |
| 51 | ||
| 52 | /* mm helpers */ | |
| 53 | static inline int handle_userfault(struct vm_area_struct *vma, | |
| 54 | unsigned long address, | |
| 55 | unsigned int flags, | |
| 56 | unsigned long reason) | |
| 57 | { | |
| 58 | return VM_FAULT_SIGBUS; | |
| 59 | } | |
| 60 | ||
| 61 | static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, | |
| 62 | struct vm_userfaultfd_ctx vm_ctx) | |
| 63 | { | |
| 64 | return true; | |
| 65 | } | |
| 66 | ||
| 67 | static inline bool userfaultfd_missing(struct vm_area_struct *vma) | |
| 68 | { | |
| 69 | return false; | |
| 70 | } | |
| 71 | ||
| 72 | static inline bool userfaultfd_armed(struct vm_area_struct *vma) | |
| 73 | { | |
| 74 | return false; | |
| 75 | } | |
| 76 | ||
| 77 | #endif /* CONFIG_USERFAULTFD */ | |
| 78 | ||
| 79 | #endif /* _LINUX_USERFAULTFD_K_H */ |