[PATCH v2] fs: Un-inline page_mkwrite_check_truncate

[Andreas Gruenbacher <agruenba@redhat.com>]

Per review comments from Jan and Ted, un-inline page_mkwrite_check_truncate
and move it to mm/filemap.c.  This function doesn't seem worth inlining.

v2: Define page_mkwrite_check_truncate outside the CONFIG_MMU guard in
mm/filemap.c to allow block_page_mkwrite to use this helper on
ARCH=m68k.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Theodore Y. Ts'o <tytso@mit.edu>
---
 include/linux/pagemap.h | 28 +---------------------------
 mm/filemap.c            | 28 ++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 27 deletions(-)

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index ccb14b6a16b5..6c9c5b88924d 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -636,32 +636,6 @@ static inline unsigned long dir_pages(struct inode *inode)
 			       PAGE_SHIFT;
 }
 
-/**
- * page_mkwrite_check_truncate - check if page was truncated
- * @page: the page to check
- * @inode: the inode to check the page against
- *
- * Returns the number of bytes in the page up to EOF,
- * or -EFAULT if the page was truncated.
- */
-static inline int page_mkwrite_check_truncate(struct page *page,
-					      struct inode *inode)
-{
-	loff_t size = i_size_read(inode);
-	pgoff_t index = size >> PAGE_SHIFT;
-	int offset = offset_in_page(size);
-
-	if (page->mapping != inode->i_mapping)
-		return -EFAULT;
-
-	/* page is wholly inside EOF */
-	if (page->index < index)
-		return PAGE_SIZE;
-	/* page is wholly past EOF */
-	if (page->index > index || !offset)
-		return -EFAULT;
-	/* page is partially inside EOF */
-	return offset;
-}
+int page_mkwrite_check_truncate(struct page *page, struct inode *inode);
 
 #endif /* _LINUX_PAGEMAP_H */
diff --git a/mm/filemap.c b/mm/filemap.c
index 1784478270e1..eac4f7e84823 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2305,6 +2305,34 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 }
 EXPORT_SYMBOL(generic_file_read_iter);
 
+/**
+ * page_mkwrite_check_truncate - check if page was truncated
+ * @page: the page to check
+ * @inode: the inode to check the page against
+ *
+ * Returns the number of bytes in the page up to EOF,
+ * or -EFAULT if the page was truncated.
+ */
+int page_mkwrite_check_truncate(struct page *page, struct inode *inode)
+{
+	loff_t size = i_size_read(inode);
+	pgoff_t index = size >> PAGE_SHIFT;
+	int offset = offset_in_page(size);
+
+	if (page->mapping != inode->i_mapping)
+		return -EFAULT;
+
+	/* page is wholly inside EOF */
+	if (page->index < index)
+		return PAGE_SIZE;
+	/* page is wholly past EOF */
+	if (page->index > index || !offset)
+		return -EFAULT;
+	/* page is partially inside EOF */
+	return offset;
+}
+EXPORT_SYMBOL(page_mkwrite_check_truncate);
+
 #ifdef CONFIG_MMU
 #define MMAP_LOTSAMISS  (100)
 /*
-- 
2.24.1