fs: ocfs2: use new return type vm_fault_t

Use new return type vm_fault_t for fault handler.  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.

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

vmf_error() is the newly introduce inline function in 4.18.

Fix one checkpatch.pl warning by replacing BUG_ON() with WARN_ON()

[akpm@linux-foundation.org: undo BUG_ON->WARN_ON change]
Link: http://lkml.kernel.org/r/20180523153258.GA28451@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/ocfs2/mmap.c b/fs/ocfs2/mmap.c
index fb9a20e3d608508db994024558fbea027486f998..05220b365fb96cff1ea3701af72fb51c681cd20a 100644 (file)
--- a/fs/ocfs2/mmap.c
+++ b/fs/ocfs2/mmap.c
@@ -44,11 +44,11 @@
 #include "ocfs2_trace.h"
 
 
-static int ocfs2_fault(struct vm_fault *vmf)
+static vm_fault_t ocfs2_fault(struct vm_fault *vmf)
 {
        struct vm_area_struct *vma = vmf->vma;
        sigset_t oldset;
-       int ret;
+       vm_fault_t ret;
 
        ocfs2_block_signals(&oldset);
        ret = filemap_fault(vmf);
@@ -59,10 +59,11 @@ static int ocfs2_fault(struct vm_fault *vmf)
        return ret;
 }
 
-static int __ocfs2_page_mkwrite(struct file *file, struct buffer_head *di_bh,
-                               struct page *page)
+static vm_fault_t __ocfs2_page_mkwrite(struct file *file,
+                       struct buffer_head *di_bh, struct page *page)
 {
-       int ret = VM_FAULT_NOPAGE;
+       int err;
+       vm_fault_t ret = VM_FAULT_NOPAGE;
        struct inode *inode = file_inode(file);
        struct address_space *mapping = inode->i_mapping;
        loff_t pos = page_offset(page);
@@ -105,15 +106,12 @@ static int __ocfs2_page_mkwrite(struct file *file, struct buffer_head *di_bh,
        if (page->index == last_index)
                len = ((size - 1) & ~PAGE_MASK) + 1;
 
-       ret = ocfs2_write_begin_nolock(mapping, pos, len, OCFS2_WRITE_MMAP,
+       err = ocfs2_write_begin_nolock(mapping, pos, len, OCFS2_WRITE_MMAP,
                                       &locked_page, &fsdata, di_bh, page);
-       if (ret) {
-               if (ret != -ENOSPC)
-                       mlog_errno(ret);
-               if (ret == -ENOMEM)
-                       ret = VM_FAULT_OOM;
-               else
-                       ret = VM_FAULT_SIGBUS;
+       if (err) {
+               if (err != -ENOSPC)
+                       mlog_errno(err);
+               ret = vmf_error(err);
                goto out;
        }
 
@@ -121,20 +119,21 @@ static int __ocfs2_page_mkwrite(struct file *file, struct buffer_head *di_bh,
                ret = VM_FAULT_NOPAGE;
                goto out;
        }
-       ret = ocfs2_write_end_nolock(mapping, pos, len, len, fsdata);
-       BUG_ON(ret != len);
+       err = ocfs2_write_end_nolock(mapping, pos, len, len, fsdata);
+       BUG_ON(err != len);
        ret = VM_FAULT_LOCKED;
 out:
        return ret;
 }
 
-static int ocfs2_page_mkwrite(struct vm_fault *vmf)
+static vm_fault_t ocfs2_page_mkwrite(struct vm_fault *vmf)
 {
        struct page *page = vmf->page;
        struct inode *inode = file_inode(vmf->vma->vm_file);
        struct buffer_head *di_bh = NULL;
        sigset_t oldset;
-       int ret;
+       int err;
+       vm_fault_t ret;
 
        sb_start_pagefault(inode->i_sb);
        ocfs2_block_signals(&oldset);
@@ -144,13 +143,10 @@ static int ocfs2_page_mkwrite(struct vm_fault *vmf)
         * node. Taking the data lock will also ensure that we don't
         * attempt page truncation as part of a downconvert.
         */
-       ret = ocfs2_inode_lock(inode, &di_bh, 1);
-       if (ret < 0) {
-               mlog_errno(ret);
-               if (ret == -ENOMEM)
-                       ret = VM_FAULT_OOM;
-               else
-                       ret = VM_FAULT_SIGBUS;
+       err = ocfs2_inode_lock(inode, &di_bh, 1);
+       if (err < 0) {
+               mlog_errno(err);
+               ret = vmf_error(err);
                goto out;
        }