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/mmap.c b/mm/mmap.c
index 39bd60c..7ed7cfc 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -198,7 +198,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 	bool downgraded = false;
 	LIST_HEAD(uf);
 
-	if (down_write_killable(&mm->mmap_sem))
+	if (mmap_write_lock_killable(mm))
 		return -EINTR;
 
 	origbrk = mm->brk;
@@ -272,9 +272,9 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 success:
 	populate = newbrk > oldbrk && (mm->def_flags & VM_LOCKED) != 0;
 	if (downgraded)
-		up_read(&mm->mmap_sem);
+		mmap_read_unlock(mm);
 	else
-		up_write(&mm->mmap_sem);
+		mmap_write_unlock(mm);
 	userfaultfd_unmap_complete(mm, &uf);
 	if (populate)
 		mm_populate(oldbrk, newbrk - oldbrk);
@@ -282,7 +282,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 
 out:
 	retval = origbrk;
-	up_write(&mm->mmap_sem);
+	mmap_write_unlock(mm);
 	return retval;
 }
 
@@ -2828,7 +2828,7 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
 	detach_vmas_to_be_unmapped(mm, vma, prev, end);
 
 	if (downgrade)
-		downgrade_write(&mm->mmap_sem);
+		mmap_write_downgrade(mm);
 
 	unmap_region(mm, vma, prev, start, end);
 
@@ -2850,7 +2850,7 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade)
 	struct mm_struct *mm = current->mm;
 	LIST_HEAD(uf);
 
-	if (down_write_killable(&mm->mmap_sem))
+	if (mmap_write_lock_killable(mm))
 		return -EINTR;
 
 	ret = __do_munmap(mm, start, len, &uf, downgrade);
@@ -2860,10 +2860,10 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade)
 	 * it to 0 before return.
 	 */
 	if (ret == 1) {
-		up_read(&mm->mmap_sem);
+		mmap_read_unlock(mm);
 		ret = 0;
 	} else
-		up_write(&mm->mmap_sem);
+		mmap_write_unlock(mm);
 
 	userfaultfd_unmap_complete(mm, &uf);
 	return ret;
@@ -2911,7 +2911,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
 	if (pgoff + (size >> PAGE_SHIFT) < pgoff)
 		return ret;
 
-	if (down_write_killable(&mm->mmap_sem))
+	if (mmap_write_lock_killable(mm))
 		return -EINTR;
 
 	vma = find_vma(mm, start);
@@ -2974,7 +2974,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
 			prot, flags, pgoff, &populate, NULL);
 	fput(file);
 out:
-	up_write(&mm->mmap_sem);
+	mmap_write_unlock(mm);
 	if (populate)
 		mm_populate(ret, populate);
 	if (!IS_ERR_VALUE(ret))
@@ -3074,12 +3074,12 @@ int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags)
 	if (!len)
 		return 0;
 
-	if (down_write_killable(&mm->mmap_sem))
+	if (mmap_write_lock_killable(mm))
 		return -EINTR;
 
 	ret = do_brk_flags(addr, len, flags, &uf);
 	populate = ((mm->def_flags & VM_LOCKED) != 0);
-	up_write(&mm->mmap_sem);
+	mmap_write_unlock(mm);
 	userfaultfd_unmap_complete(mm, &uf);
 	if (populate && !ret)
 		mm_populate(addr, len);
@@ -3123,8 +3123,8 @@ void exit_mmap(struct mm_struct *mm)
 		(void)__oom_reap_task_mm(mm);
 
 		set_bit(MMF_OOM_SKIP, &mm->flags);
-		down_write(&mm->mmap_sem);
-		up_write(&mm->mmap_sem);
+		mmap_write_lock(mm);
+		mmap_write_unlock(mm);
 	}
 
 	if (mm->locked_vm) {
@@ -3550,7 +3550,7 @@ int mm_take_all_locks(struct mm_struct *mm)
 	struct vm_area_struct *vma;
 	struct anon_vma_chain *avc;
 
-	BUG_ON(down_read_trylock(&mm->mmap_sem));
+	BUG_ON(mmap_read_trylock(mm));
 
 	mutex_lock(&mm_all_locks_mutex);
 
@@ -3630,7 +3630,7 @@ void mm_drop_all_locks(struct mm_struct *mm)
 	struct vm_area_struct *vma;
 	struct anon_vma_chain *avc;
 
-	BUG_ON(down_read_trylock(&mm->mmap_sem));
+	BUG_ON(mmap_read_trylock(mm));
 	BUG_ON(!mutex_is_locked(&mm_all_locks_mutex));
 
 	for (vma = mm->mmap; vma; vma = vma->vm_next) {