[PATCH v3] mm: Change return type to vm_fault_t

[Souptick Joarder]

Use new return type vm_fault_t for fault handler
in struct vm_operations_struct. For now, this is
just documenting that the function returns a
VM_FAULT value rather than an errno.  Once all
instances are converted, vm_fault_t will become
a distinct type.

commit 1c8f422059ae ("mm: change return type to
vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.li...@gmail.com>
Reviewed-by: Matthew Wilcox <mawil...@microsoft.com>
---
v2: updated the change log

v3: added <linux/mm_types.h> changes
    into the same patch

 include/linux/mm_types.h | 2 +-
 mm/hugetlb.c             | 2 +-
 mm/mmap.c                | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 2161234..11acfdb 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -627,7 +627,7 @@ struct vm_special_mapping {
         * If non-NULL, then this is called to resolve page faults
         * on the special mapping.  If used, .pages is not checked.
         */
-       int (*fault)(const struct vm_special_mapping *sm,
+       vm_fault_t (*fault)(const struct vm_special_mapping *sm,
                     struct vm_area_struct *vma,
                     struct vm_fault *vmf);
 
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 2186791..7e00bd3 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3159,7 +3159,7 @@ static unsigned long hugetlb_vm_op_pagesize(struct 
vm_area_struct *vma)
  * hugegpage VMA.  do_page_fault() is supposed to trap this, so BUG is we get
  * this far.
  */
-static int hugetlb_vm_op_fault(struct vm_fault *vmf)
+static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf)
 {
        BUG();
        return 0;
diff --git a/mm/mmap.c b/mm/mmap.c
index 188f195..bdd4ba9a 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3228,7 +3228,7 @@ void vm_stat_account(struct mm_struct *mm, vm_flags_t 
flags, long npages)
                mm->data_vm += npages;
 }
 
-static int special_mapping_fault(struct vm_fault *vmf);
+static vm_fault_t special_mapping_fault(struct vm_fault *vmf);
 
 /*
  * Having a close hook prevents vma merging regardless of flags.
@@ -3267,7 +3267,7 @@ static int special_mapping_mremap(struct vm_area_struct 
*new_vma)
        .fault = special_mapping_fault,
 };
 
-static int special_mapping_fault(struct vm_fault *vmf)
+static vm_fault_t special_mapping_fault(struct vm_fault *vmf)
 {
        struct vm_area_struct *vma = vmf->vma;
        pgoff_t pgoff;
-- 
1.9.1