diff options
| author | Lorenzo Stoakes <lstoakes@gmail.com> | 2016-10-13 01:20:12 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-17 21:55:16 +0100 |
| commit | ab424c8eb71ee9ea4ba798faaeaf62e84048cb9a (patch) | |
| tree | 24ed72e49c33b6aade395525b9710f19cf96984d /mm | |
| parent | 6a3c9524df93e9597d30c2d32114950772fce58e (diff) | |
mm: remove write/force parameters from __get_user_pages_unlocked()
commit d4944b0ecec0af882483fe44b66729316e575208 upstream.
This removes the redundant 'write' and 'force' parameters from
__get_user_pages_unlocked() 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: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.4:
- Defer changes in process_vm_rw_single_vec() and async_pf_execute() since
they use get_user_pages_unlocked() here
- Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/gup.c | 19 | ||||
| -rw-r--r-- | mm/nommu.c | 14 |
2 files changed, 20 insertions, 13 deletions
@@ -764,17 +764,11 @@ EXPORT_SYMBOL(get_user_pages_locked); */ __always_inline long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - unsigned int gup_flags) + struct page **pages, unsigned int gup_flags) { long ret; int locked = 1; - if (write) - gup_flags |= FOLL_WRITE; - if (force) - gup_flags |= FOLL_FORCE; - down_read(&mm->mmap_sem); ret = __get_user_pages_locked(tsk, mm, start, nr_pages, pages, NULL, &locked, false, gup_flags); @@ -805,8 +799,15 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages) { - return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write, - force, pages, FOLL_TOUCH); + unsigned int flags = FOLL_TOUCH; + + if (write) + flags |= FOLL_WRITE; + if (force) + flags |= FOLL_FORCE; + + return __get_user_pages_unlocked(tsk, mm, start, nr_pages, + pages, flags); } EXPORT_SYMBOL(get_user_pages_unlocked); diff --git a/mm/nommu.c b/mm/nommu.c index 92be862c859b..5462ed88a548 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -211,8 +211,7 @@ EXPORT_SYMBOL(get_user_pages_locked); long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - unsigned int gup_flags) + struct page **pages, unsigned int gup_flags) { long ret; down_read(&mm->mmap_sem); @@ -227,8 +226,15 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages) { - return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write, - force, pages, 0); + unsigned int flags = 0; + + if (write) + flags |= FOLL_WRITE; + if (force) + flags |= FOLL_FORCE; + + return __get_user_pages_unlocked(tsk, mm, start, nr_pages, + pages, flags); } EXPORT_SYMBOL(get_user_pages_unlocked); |