From dbe6ec815641aa22b50775aaeb47fa3a8d04ccf1 Mon Sep 17 00:00:00 2001
From: Toshi Kani <toshi.kani@hpe.com>
Date: Fri, 7 Oct 2016 16:59:59 -0700
Subject: [PATCH] ext2/4, xfs: call thp_get_unmapped_area() for pmd mappings

To support DAX pmd mappings with unmodified applications, filesystems
need to align an mmap address by the pmd size.

Call thp_get_unmapped_area() from f_op->get_unmapped_area.

Note, there is no change in behavior for a non-DAX file.

Link: http://lkml.kernel.org/r/1472497881-9323-3-git-send-email-toshi.kani@hpe.com
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 fs/ext2/file.c    | 1 +
 fs/ext4/file.c    | 1 +
 fs/xfs/xfs_file.c | 1 +
 3 files changed, 3 insertions(+)

diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 423cc01c9d41..0ca363d1341c 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -234,6 +234,7 @@ const struct file_operations ext2_file_operations = {
 	.open		= dquot_file_open,
 	.release	= ext2_release_file,
 	.fsync		= ext2_fsync,
+	.get_unmapped_area = thp_get_unmapped_area,
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= iter_file_splice_write,
 };
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 261ac3734c58..28f542bb0bda 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -703,6 +703,7 @@ const struct file_operations ext4_file_operations = {
 	.open		= ext4_file_open,
 	.release	= ext4_release_file,
 	.fsync		= ext4_sync_file,
+	.get_unmapped_area = thp_get_unmapped_area,
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= iter_file_splice_write,
 	.fallocate	= ext4_fallocate,
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index c68517b0f248..bac55c687085 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1618,6 +1618,7 @@ const struct file_operations xfs_file_operations = {
 	.open		= xfs_file_open,
 	.release	= xfs_file_release,
 	.fsync		= xfs_file_fsync,
+	.get_unmapped_area = thp_get_unmapped_area,
 	.fallocate	= xfs_file_fallocate,
 };
 
-- 
2.20.1