mm: replace access_process_vm() write parameter with gup_flags
This removes the 'write' argument from access_process_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/nommu.c b/mm/nommu.c
index 93d5bb5..db5fd17 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1861,7 +1861,8 @@
* Access another process' address space.
* - source/target buffer must be kernel space
*/
-int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
+int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len,
+ unsigned int gup_flags)
{
struct mm_struct *mm;
@@ -1872,8 +1873,7 @@
if (!mm)
return 0;
- len = __access_remote_vm(tsk, mm, addr, buf, len,
- write ? FOLL_WRITE : 0);
+ len = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags);
mmput(mm);
return len;