mm: move common segment checks to separate helper function

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Monakhov Dmitriy <dmonakhov@openvz.org>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Anton Altaparmakov <aia21@cam.ac.uk>
Acked-by: David Chinner <dgc@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index bc6d27c..020a842 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1735,6 +1735,8 @@
 extern void do_generic_mapping_read(struct address_space *mapping,
 				    struct file_ra_state *, struct file *,
 				    loff_t *, read_descriptor_t *, read_actor_t);
+extern int generic_segment_checks(const struct iovec *iov,
+		unsigned long *nr_segs, size_t *count, int access_flags);
 
 /* fs/splice.c */
 extern ssize_t generic_file_splice_read(struct file *, loff_t *,