vfs: Rename generic_file_aio_write_nolock

generic_file_aio_write_nolock() is now used only by block devices and raw
character device. Filesystems should use __generic_file_aio_write() in case
generic_file_aio_write() doesn't suit them. So rename the function to
blkdev_aio_write() and move it to fs/blockdev.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

drivers/char/raw.c

@@ -246,7 +246,7 @@ static const struct file_operations raw_fops = {
 	.read	=	do_sync_read,
 	.aio_read = 	generic_file_aio_read,
 	.write	=	do_sync_write,
-	.aio_write = 	generic_file_aio_write_nolock,
+	.aio_write =	blkdev_aio_write,
 	.open	=	raw_open,
 	.release=	raw_release,
 	.ioctl	=	raw_ioctl,

fs/block_dev.c

@@ -1404,6 +1404,33 @@ static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	return blkdev_ioctl(bdev, mode, cmd, arg);
 }
 
+/*
+ * Write data to the block device.  Only intended for the block device itself
+ * and the raw driver which basically is a fake block device.
+ *
+ * Does not take i_mutex for the write and thus is not for general purpose
+ * use.
+ */
+ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
+			 unsigned long nr_segs, loff_t pos)
+{
+	struct file *file = iocb->ki_filp;
+	ssize_t ret;
+
+	BUG_ON(iocb->ki_pos != pos);
+
+	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
+	if (ret > 0 || ret == -EIOCBQUEUED) {
+		ssize_t err;
+
+		err = generic_write_sync(file, pos, ret);
+		if (err < 0 && ret > 0)
+			ret = err;
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(blkdev_aio_write);
+
 /*
  * Try to release a page associated with block device when the system
  * is under memory pressure.
@@ -1436,7 +1463,7 @@ const struct file_operations def_blk_fops = {
 	.read		= do_sync_read,
 	.write		= do_sync_write,
   	.aio_read	= generic_file_aio_read,
-  	.aio_write	= generic_file_aio_write_nolock,
+	.aio_write	= blkdev_aio_write,
 	.mmap		= generic_file_mmap,
 	.fsync		= block_fsync,
 	.unlocked_ioctl	= block_ioctl,

include/linux/fs.h

@@ -2207,8 +2207,6 @@ extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsig
 extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
 		loff_t *);
 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
-extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
-		unsigned long, loff_t);
 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
 		unsigned long *, loff_t, loff_t *, size_t, size_t);
 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
@@ -2218,6 +2216,10 @@ extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t l
 extern int generic_segment_checks(const struct iovec *iov,
 		unsigned long *nr_segs, size_t *count, int access_flags);
 
+/* fs/block_dev.c */
+extern ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov,
+				unsigned long nr_segs, loff_t pos);
+
 /* fs/splice.c */
 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
 		struct pipe_inode_info *, size_t, unsigned int);

mm/filemap.c

@@ -2462,45 +2462,6 @@ out:
 }
 EXPORT_SYMBOL(__generic_file_aio_write);
 
-
-/**
- * generic_file_aio_write_nolock - write data, usually to a device
- * @iocb:	IO state structure
- * @iov:	vector with data to write
- * @nr_segs:	number of segments in the vector
- * @pos:	position in file where to write
- *
- * This is a wrapper around __generic_file_aio_write() which takes care of
- * syncing the file in case of O_SYNC file. It does not take i_mutex for the
- * write itself but may do so during syncing. It is meant for users like block
- * devices which do not need i_mutex during write. If your filesystem needs to
- * do a write but already holds i_mutex, use __generic_file_aio_write()
- * directly and then sync the file like generic_file_aio_write().
- */
-ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
-		const struct iovec *iov, unsigned long nr_segs, loff_t pos)
-{
-	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
-	ssize_t ret;
-
-	BUG_ON(iocb->ki_pos != pos);
-
-	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
-
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-		ssize_t err;
-
-		err = sync_page_range_nolock(inode, mapping, pos, ret);
-		if (err < 0 && ret > 0)
-			ret = err;
-	}
-	return ret;
-}
-EXPORT_SYMBOL(generic_file_aio_write_nolock);
-
 /**
  * generic_file_aio_write - write data to a file
  * @iocb:	IO state structure