diff options
| author | Lorenzo Stoakes <lstoakes@gmail.com> | 2016-10-12 20:20:14 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-10-19 11:11:05 -0400 |
| commit | 3b913179c3fa89dd0e304193fa0c746fc0481447 (patch) | |
| tree | 9d19f80b42aa94ccdd93d926332aee9881ac439b /mm | |
| parent | c164154f66f0c9b02673f07aa4f044f1d9c70274 (diff) | |
mm: replace get_user_pages_locked() write/force parameters with gup_flags
This removes the 'write' and 'force' use from get_user_pages_locked()
and replaces them with 'gup_flags' to make the use of FOLL_FORCE
explicit in callers as use of this flag can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/frame_vector.c | 8 | ||||
| -rw-r--r-- | mm/gup.c | 12 | ||||
| -rw-r--r-- | mm/nommu.c | 5 |
3 files changed, 14 insertions, 11 deletions
diff --git a/mm/frame_vector.c b/mm/frame_vector.c index 381bb07ed14f..81b67498bb9c 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c | |||
| @@ -41,10 +41,16 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, | |||
| 41 | int ret = 0; | 41 | int ret = 0; |
| 42 | int err; | 42 | int err; |
| 43 | int locked; | 43 | int locked; |
| 44 | unsigned int gup_flags = 0; | ||
| 44 | 45 | ||
| 45 | if (nr_frames == 0) | 46 | if (nr_frames == 0) |
| 46 | return 0; | 47 | return 0; |
| 47 | 48 | ||
| 49 | if (write) | ||
| 50 | gup_flags |= FOLL_WRITE; | ||
| 51 | if (force) | ||
| 52 | gup_flags |= FOLL_FORCE; | ||
| 53 | |||
| 48 | if (WARN_ON_ONCE(nr_frames > vec->nr_allocated)) | 54 | if (WARN_ON_ONCE(nr_frames > vec->nr_allocated)) |
| 49 | nr_frames = vec->nr_allocated; | 55 | nr_frames = vec->nr_allocated; |
| 50 | 56 | ||
| @@ -59,7 +65,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, | |||
| 59 | vec->got_ref = true; | 65 | vec->got_ref = true; |
| 60 | vec->is_pfns = false; | 66 | vec->is_pfns = false; |
| 61 | ret = get_user_pages_locked(start, nr_frames, | 67 | ret = get_user_pages_locked(start, nr_frames, |
| 62 | write, force, (struct page **)(vec->ptrs), &locked); | 68 | gup_flags, (struct page **)(vec->ptrs), &locked); |
| 63 | goto out; | 69 | goto out; |
| 64 | } | 70 | } |
| 65 | 71 | ||
| @@ -848,18 +848,12 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, | |||
| 848 | * up_read(&mm->mmap_sem); | 848 | * up_read(&mm->mmap_sem); |
| 849 | */ | 849 | */ |
| 850 | long get_user_pages_locked(unsigned long start, unsigned long nr_pages, | 850 | long get_user_pages_locked(unsigned long start, unsigned long nr_pages, |
| 851 | int write, int force, struct page **pages, | 851 | unsigned int gup_flags, struct page **pages, |
| 852 | int *locked) | 852 | int *locked) |
| 853 | { | 853 | { |
| 854 | unsigned int flags = FOLL_TOUCH; | ||
| 855 | |||
| 856 | if (write) | ||
| 857 | flags |= FOLL_WRITE; | ||
| 858 | if (force) | ||
| 859 | flags |= FOLL_FORCE; | ||
| 860 | |||
| 861 | return __get_user_pages_locked(current, current->mm, start, nr_pages, | 854 | return __get_user_pages_locked(current, current->mm, start, nr_pages, |
| 862 | pages, NULL, locked, true, flags); | 855 | pages, NULL, locked, true, |
| 856 | gup_flags | FOLL_TOUCH); | ||
| 863 | } | 857 | } |
| 864 | EXPORT_SYMBOL(get_user_pages_locked); | 858 | EXPORT_SYMBOL(get_user_pages_locked); |
| 865 | 859 | ||
diff --git a/mm/nommu.c b/mm/nommu.c index 7e27add39f7e..842cfdd1a31e 100644 --- a/mm/nommu.c +++ b/mm/nommu.c | |||
| @@ -176,9 +176,12 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, | |||
| 176 | EXPORT_SYMBOL(get_user_pages); | 176 | EXPORT_SYMBOL(get_user_pages); |
| 177 | 177 | ||
| 178 | long get_user_pages_locked(unsigned long start, unsigned long nr_pages, | 178 | long get_user_pages_locked(unsigned long start, unsigned long nr_pages, |
| 179 | int write, int force, struct page **pages, | 179 | unsigned int gup_flags, struct page **pages, |
| 180 | int *locked) | 180 | int *locked) |
| 181 | { | 181 | { |
| 182 | int write = gup_flags & FOLL_WRITE; | ||
| 183 | int force = gup_flags & FOLL_FORCE; | ||
| 184 | |||
| 182 | return get_user_pages(start, nr_pages, write, force, pages, NULL); | 185 | return get_user_pages(start, nr_pages, write, force, pages, NULL); |
| 183 | } | 186 | } |
| 184 | EXPORT_SYMBOL(get_user_pages_locked); | 187 | EXPORT_SYMBOL(get_user_pages_locked); |