mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf

->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/relay.c b/kernel/relay.c
index 8f18d31..8f8dc91 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -39,10 +39,10 @@ static void relay_file_mmap_close(struct vm_area_struct *vma)
 /*
  * fault() vm_op implementation for relay file mapping.
  */
-static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+static int relay_buf_fault(struct vm_fault *vmf)
 {
 	struct page *page;
-	struct rchan_buf *buf = vma->vm_private_data;
+	struct rchan_buf *buf = vmf->vma->vm_private_data;
 	pgoff_t pgoff = vmf->pgoff;
 
 	if (!buf)