Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...

fs/fat/file.c

@@ -170,10 +170,10 @@ int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
 
 const struct file_operations fat_file_operations = {
 	.llseek		= generic_file_llseek,
-	.read		= do_sync_read,
-	.write		= do_sync_write,
-	.aio_read	= generic_file_aio_read,
-	.aio_write	= generic_file_aio_write,
+	.read		= new_sync_read,
+	.write		= new_sync_write,
+	.read_iter	= generic_file_read_iter,
+	.write_iter	= generic_file_write_iter,
 	.mmap		= generic_file_mmap,
 	.release	= fat_file_release,
 	.unlocked_ioctl	= fat_generic_ioctl,

fs/fat/inode.c

@@ -247,12 +247,13 @@ static int fat_write_end(struct file *file, struct address_space *mapping,
 }
 
 static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
-			     const struct iovec *iov,
-			     loff_t offset, unsigned long nr_segs)
+			     struct iov_iter *iter,
+			     loff_t offset)
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
+	size_t count = iov_iter_count(iter);
 	ssize_t ret;
 
 	if (rw == WRITE) {
@@ -265,7 +266,7 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
 		 *
 		 * Return 0, and fallback to normal buffered write.
 		 */
-		loff_t size = offset + iov_length(iov, nr_segs);
+		loff_t size = offset + count;
 		if (MSDOS_I(inode)->mmu_private < size)
 			return 0;
 	}
@@ -274,10 +275,9 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
 	 * FAT need to use the DIO_LOCKING for avoiding the race
 	 * condition of fat_get_block() and ->truncate().
 	 */
-	ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
-				 fat_get_block);
+	ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, fat_get_block);
 	if (ret < 0 && (rw & WRITE))
-		fat_write_failed(mapping, offset + iov_length(iov, nr_segs));
+		fat_write_failed(mapping, offset + count);
 
 	return ret;
 }