1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) Microsoft Corporation.
4  *
5  * Author:
6  *   Haiyang Zhang <haiyangz@microsoft.com>
7  *
8  * This small module is a helper driver allows other drivers to
9  * have a common interface with the Hyper-V PCI frontend driver.
10  */
11 
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/hyperv.h>
17 
18 struct hyperv_pci_block_ops hvpci_block_ops;
19 EXPORT_SYMBOL_GPL(hvpci_block_ops);
20 
21 int hyperv_read_cfg_blk(struct pci_dev *dev, void *buf, unsigned int buf_len,
22 			unsigned int block_id, unsigned int *bytes_returned)
23 {
24 	if (!hvpci_block_ops.read_block)
25 		return -EOPNOTSUPP;
26 
27 	return hvpci_block_ops.read_block(dev, buf, buf_len, block_id,
28 					  bytes_returned);
29 }
30 EXPORT_SYMBOL_GPL(hyperv_read_cfg_blk);
31 
32 int hyperv_write_cfg_blk(struct pci_dev *dev, void *buf, unsigned int len,
33 			 unsigned int block_id)
34 {
35 	if (!hvpci_block_ops.write_block)
36 		return -EOPNOTSUPP;
37 
38 	return hvpci_block_ops.write_block(dev, buf, len, block_id);
39 }
40 EXPORT_SYMBOL_GPL(hyperv_write_cfg_blk);
41 
42 int hyperv_reg_block_invalidate(struct pci_dev *dev, void *context,
43 				void (*block_invalidate)(void *context,
44 							 u64 block_mask))
45 {
46 	if (!hvpci_block_ops.reg_blk_invalidate)
47 		return -EOPNOTSUPP;
48 
49 	return hvpci_block_ops.reg_blk_invalidate(dev, context,
50 						  block_invalidate);
51 }
52 EXPORT_SYMBOL_GPL(hyperv_reg_block_invalidate);
53 
54 static void __exit exit_hv_pci_intf(void)
55 {
56 }
57 
58 static int __init init_hv_pci_intf(void)
59 {
60 	return 0;
61 }
62 
63 module_init(init_hv_pci_intf);
64 module_exit(exit_hv_pci_intf);
65 
66 MODULE_DESCRIPTION("Hyper-V PCI Interface");
67 MODULE_LICENSE("GPL v2");
68