[PATCH] mm/hmm: Convert to use vm_fault_t

[Souptick Joarder <jrdr.linux@gmail.com>]

convert to use vm_fault_t type as return type for
fault handler.

kbuild reported warning during testing of
*mm-create-the-new-vm_fault_t-type.patch* available in below link -
https://patchwork.kernel.org/patch/10752741/

[auto build test WARNING on linus/master]
[also build test WARNING on v5.0-rc1 next-20190109]
[if your patch is applied to the wrong git tree, please drop us a note
to help improve the system]

kernel/memremap.c:46:34: warning: incorrect type in return expression
                         (different base types)
kernel/memremap.c:46:34: expected restricted vm_fault_t
kernel/memremap.c:46:34: got int

This patch has fixed the warnings and also hmm_devmem_fault() is
converted to return vm_fault_t to avoid further warnings.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
---
 include/linux/hmm.h | 4 ++--
 mm/hmm.c            | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 66f9ebb..ad50b7b 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -468,7 +468,7 @@ struct hmm_devmem_ops {
 	 * Note that mmap semaphore is held in read mode at least when this
 	 * callback occurs, hence the vma is valid upon callback entry.
 	 */
-	int (*fault)(struct hmm_devmem *devmem,
+	vm_fault_t (*fault)(struct hmm_devmem *devmem,
 		     struct vm_area_struct *vma,
 		     unsigned long addr,
 		     const struct page *page,
@@ -511,7 +511,7 @@ struct hmm_devmem_ops {
  * chunk, as an optimization. It must, however, prioritize the faulting address
  * over all the others.
  */
-typedef int (*dev_page_fault_t)(struct vm_area_struct *vma,
+typedef vm_fault_t (*dev_page_fault_t)(struct vm_area_struct *vma,
 				unsigned long addr,
 				const struct page *page,
 				unsigned int flags,
diff --git a/mm/hmm.c b/mm/hmm.c
index a04e4b8..fe1cd87 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -990,7 +990,7 @@ static void hmm_devmem_ref_kill(struct percpu_ref *ref)
 	percpu_ref_kill(ref);
 }
 
-static int hmm_devmem_fault(struct vm_area_struct *vma,
+static vm_fault_t hmm_devmem_fault(struct vm_area_struct *vma,
 			    unsigned long addr,
 			    const struct page *page,
 			    unsigned int flags,
-- 
1.9.1