mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
index 4107dbc..c2578e1 100644
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -48,7 +48,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
 
 	start = untagged_addr(start);
 
-	down_read(&mm->mmap_sem);
+	mmap_read_lock(mm);
 	locked = 1;
 	vma = find_vma_intersection(mm, start, start + 1);
 	if (!vma) {
@@ -102,7 +102,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
 	} while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
 out:
 	if (locked)
-		up_read(&mm->mmap_sem);
+		mmap_read_unlock(mm);
 	if (!ret)
 		ret = -EFAULT;
 	if (ret > 0)