mm: change return type to vm_fault_t

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.

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

Link: http://lkml.kernel.org/r/20180512063745.GA26866@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 49dd59e..eb9da24 100644 (file)
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -629,9 +629,9 @@ 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,
-                    struct vm_area_struct *vma,
-                    struct vm_fault *vmf);
+       vm_fault_t (*fault)(const struct vm_special_mapping *sm,
+                               struct vm_area_struct *vma,
+                               struct vm_fault *vmf);
 
        int (*mremap)(const struct vm_special_mapping *sm,
                     struct vm_area_struct *new_vma);

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 1290887..6c6decc 100644 (file)
--- 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 d817764..d1eb87e 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3277,7 +3277,7 @@ 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.
@@ -3316,7 +3316,7 @@ static const struct vm_operations_struct legacy_special_mapping_vmops = {
        .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;