This is in preparation for enabling this functionality through io_uring.
Add a helper that is just exporting what sys_madvise() does, and have the
system call use it.
No functional changes in this patch.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
include/linux/mm.h | 1 +
mm/madvise.c | 7 ++++++-
2 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 80a9162b406c..766cad8aaa60 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2328,6 +2328,7 @@ extern int __do_munmap(struct mm_struct *, unsigned long, size_t,
struct list_head *uf, bool downgrade);
extern int do_munmap(struct mm_struct *, unsigned long, size_t,
struct list_head *uf);
+extern int do_madvise(unsigned long start, size_t len_in, int behavior);
static inline unsigned long
do_mmap_pgoff(struct file *file, unsigned long addr,
diff --git a/mm/madvise.c b/mm/madvise.c
index bcdb6a042787..43b47d3fae02 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -1044,7 +1044,7 @@ madvise_behavior_valid(int behavior)
* -EBADF - map exists, but area maps something that isn't a file.
* -EAGAIN - a kernel resource was temporarily unavailable.
*/
-SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
+int do_madvise(unsigned long start, size_t len_in, int behavior)
{
unsigned long end, tmp;
struct vm_area_struct *vma, *prev;
@@ -1141,3 +1141,8 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
return error;
}
+
+SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
+{
+ return do_madvise(start, len_in, behavior);
+}
--
2.24.1
