9p: get rid of v9fs_direct_file_write()

just handle it in ->direct_IO()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/9p/vfs_addr.c

@@ -252,15 +252,21 @@ static int v9fs_launder_page(struct page *page)
 static ssize_t
 v9fs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, loff_t pos)
 {
-	/*
-	 * FIXME
-	 * Now that we do caching with cache mode enabled, We need
-	 * to support direct IO
-	 */
-	p9_debug(P9_DEBUG_VFS, "v9fs_direct_IO: v9fs_direct_IO (%pD) off/no(%lld/%lu) EINVAL\n",
-		 iocb->ki_filp,
-		 (long long)pos, iter->nr_segs);
-
+	struct file *file = iocb->ki_filp;
+	if (rw == WRITE) {
+		ssize_t written;
+		int err = 0;
+
+		written = p9_client_write(file->private_data, pos, iter, &err);
+		if (written) {
+			struct inode *inode = file_inode(file);
+			loff_t i_size = i_size_read(inode);
+			if (pos + written > i_size)
+				inode_add_bytes(inode, pos + written - i_size);
+			return written;
+		}
+		return err;
+	}
 	return -EINVAL;
 }
 

fs/9p/vfs_file.c

@@ -688,77 +688,6 @@ v9fs_mmap_file_read(struct file *filp, char __user *data, size_t count,
 	return v9fs_file_read(filp, data, count, offset);
 }
 
-static ssize_t
-v9fs_direct_write(struct file *filp, const char __user * data,
-		  size_t count, loff_t *offsetp)
-{
-	loff_t offset;
-	ssize_t retval;
-	struct inode *inode;
-	struct address_space *mapping;
-
-	offset = *offsetp;
-	mapping = filp->f_mapping;
-	inode = mapping->host;
-	if (!count)
-		return 0;
-
-	mutex_lock(&inode->i_mutex);
-	retval = filemap_write_and_wait_range(mapping, offset,
-					      offset + count - 1);
-	if (retval)
-		goto err_out;
-	/*
-	 * After a write we want buffered reads to be sure to go to disk to get
-	 * the new data.  We invalidate clean cached page from the region we're
-	 * about to write.  We do this *before* the write so that if we fail
-	 * here we fall back to buffered write
-	 */
-	if (mapping->nrpages) {
-		pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
-		pgoff_t pg_end   = (offset + count - 1) >> PAGE_CACHE_SHIFT;
-
-		retval = invalidate_inode_pages2_range(mapping,
-							pg_start, pg_end);
-		/*
-		 * If a page can not be invalidated, fall back
-		 * to buffered write.
-		 */
-		if (retval) {
-			if (retval == -EBUSY)
-				goto buff_write;
-			goto err_out;
-		}
-	}
-	retval = v9fs_file_write(filp, data, count, offsetp);
-err_out:
-	mutex_unlock(&inode->i_mutex);
-	return retval;
-
-buff_write:
-	mutex_unlock(&inode->i_mutex);
-	return new_sync_write(filp, data, count, offsetp);
-}
-
-/**
- * v9fs_cached_file_write - write to a file
- * @filp: file pointer to write
- * @data: data buffer to write data from
- * @count: size of buffer
- * @offset: offset at which to write data
- *
- */
-static ssize_t
-v9fs_cached_file_write(struct file *filp, const char __user * data,
-		       size_t count, loff_t *offset)
-{
-
-	if (filp->f_flags & O_DIRECT)
-		return v9fs_direct_write(filp, data, count, offset);
-	return new_sync_write(filp, data, count, offset);
-}
-
-
 /**
  * v9fs_mmap_file_write - write to a file
  * @filp: file pointer to write
@@ -821,7 +750,7 @@ static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
 const struct file_operations v9fs_cached_file_operations = {
 	.llseek = generic_file_llseek,
 	.read = v9fs_cached_file_read,
-	.write = v9fs_cached_file_write,
+	.write = new_sync_write,
 	.read_iter = generic_file_read_iter,
 	.write_iter = generic_file_write_iter,
 	.open = v9fs_file_open,
@@ -834,7 +763,7 @@ const struct file_operations v9fs_cached_file_operations = {
 const struct file_operations v9fs_cached_file_operations_dotl = {
 	.llseek = generic_file_llseek,
 	.read = v9fs_cached_file_read,
-	.write = v9fs_cached_file_write,
+	.write = new_sync_write,
 	.read_iter = generic_file_read_iter,
 	.write_iter = generic_file_write_iter,
 	.open = v9fs_file_open,