1 files changed, 11 insertions, 36 deletions

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 89d97f6188e0..bc4115288eec 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1280,13 +1280,13 @@ static inline unsigned int fuse_wr_pages(loff_t pos, size_t len,
 		     max_pages);
 }
 
-static ssize_t fuse_perform_write(struct kiocb *iocb,
-				  struct address_space *mapping,
-				  struct iov_iter *ii, loff_t pos)
+static ssize_t fuse_perform_write(struct kiocb *iocb, struct iov_iter *ii)
 {
+	struct address_space *mapping = iocb->ki_filp->f_mapping;
 	struct inode *inode = mapping->host;
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	struct fuse_inode *fi = get_fuse_inode(inode);
+	loff_t pos = iocb->ki_pos;
 	int err = 0;
 	ssize_t res = 0;
 
@@ -1329,7 +1329,10 @@ static ssize_t fuse_perform_write(struct kiocb *iocb,
 	fuse_write_update_attr(inode, pos, res);
 	clear_bit(FUSE_I_SIZE_UNSTABLE, &fi->state);
 
-	return res > 0 ? res : err;
+	if (!res)
+		return err;
+	iocb->ki_pos += res;
+	return res;
 }
 
 static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
@@ -1337,11 +1340,9 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
 	ssize_t written = 0;
-	ssize_t written_buffered = 0;
 	struct inode *inode = mapping->host;
 	ssize_t err;
 	struct fuse_conn *fc = get_fuse_conn(inode);
-	loff_t endbyte = 0;
 
 	if (fc->writeback_cache) {
 		/* Update size (EOF optimization) and mode (SUID clearing) */
@@ -1362,9 +1363,6 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 writethrough:
 	inode_lock(inode);
 
-	/* We can write back this queue in page reclaim */
-	current->backing_dev_info = inode_to_bdi(inode);
-
 	err = generic_write_checks(iocb, from);
 	if (err <= 0)
 		goto out;
@@ -1378,38 +1376,15 @@ writethrough:
 		goto out;
 
 	if (iocb->ki_flags & IOCB_DIRECT) {
-		loff_t pos = iocb->ki_pos;
 		written = generic_file_direct_write(iocb, from);
 		if (written < 0 || !iov_iter_count(from))
 			goto out;
-
-		pos += written;
-
-		written_buffered = fuse_perform_write(iocb, mapping, from, pos);
-		if (written_buffered < 0) {
-			err = written_buffered;
-			goto out;
-		}
-		endbyte = pos + written_buffered - 1;
-
-		err = filemap_write_and_wait_range(file->f_mapping, pos,
-						   endbyte);
-		if (err)
-			goto out;
-
-		invalidate_mapping_pages(file->f_mapping,
-					 pos >> PAGE_SHIFT,
-					 endbyte >> PAGE_SHIFT);
-
-		written += written_buffered;
-		iocb->ki_pos = pos + written_buffered;
+		written = direct_write_fallback(iocb, from, written,
+				fuse_perform_write(iocb, from));
 	} else {
-		written = fuse_perform_write(iocb, mapping, from, iocb->ki_pos);
-		if (written >= 0)
-			iocb->ki_pos += written;
+		written = fuse_perform_write(iocb, from);
 	}
 out:
-	current->backing_dev_info = NULL;
 	inode_unlock(inode);
 	if (written > 0)
 		written = generic_write_sync(iocb, written);
@@ -3252,7 +3227,7 @@ static const struct file_operations fuse_file_operations = {
 	.lock		= fuse_file_lock,
 	.get_unmapped_area = thp_get_unmapped_area,
 	.flock		= fuse_file_flock,
-	.splice_read	= generic_file_splice_read,
+	.splice_read	= filemap_splice_read,
 	.splice_write	= iter_file_splice_write,
 	.unlocked_ioctl	= fuse_file_ioctl,
 	.compat_ioctl	= fuse_file_compat_ioctl,