xref: /openbmc/linux/arch/um/drivers/vhost_user.h (revision 20e2fc42)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Vhost-user protocol */
3 
4 #ifndef __VHOST_USER_H__
5 #define __VHOST_USER_H__
6 
7 /* Message flags */
8 #define VHOST_USER_FLAG_REPLY		BIT(2)
9 #define VHOST_USER_FLAG_NEED_REPLY	BIT(3)
10 /* Feature bits */
11 #define VHOST_USER_F_PROTOCOL_FEATURES	30
12 /* Protocol feature bits */
13 #define VHOST_USER_PROTOCOL_F_REPLY_ACK		3
14 #define VHOST_USER_PROTOCOL_F_SLAVE_REQ		5
15 #define VHOST_USER_PROTOCOL_F_CONFIG		9
16 /* Vring state index masks */
17 #define VHOST_USER_VRING_INDEX_MASK	0xff
18 #define VHOST_USER_VRING_POLL_MASK	BIT(8)
19 
20 /* Supported version */
21 #define VHOST_USER_VERSION		1
22 /* Supported transport features */
23 #define VHOST_USER_SUPPORTED_F		BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES)
24 /* Supported protocol features */
25 #define VHOST_USER_SUPPORTED_PROTOCOL_F	(BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
26 					 BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ) | \
27 					 BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG))
28 
29 enum vhost_user_request {
30 	VHOST_USER_GET_FEATURES = 1,
31 	VHOST_USER_SET_FEATURES = 2,
32 	VHOST_USER_SET_OWNER = 3,
33 	VHOST_USER_RESET_OWNER = 4,
34 	VHOST_USER_SET_MEM_TABLE = 5,
35 	VHOST_USER_SET_LOG_BASE = 6,
36 	VHOST_USER_SET_LOG_FD = 7,
37 	VHOST_USER_SET_VRING_NUM = 8,
38 	VHOST_USER_SET_VRING_ADDR = 9,
39 	VHOST_USER_SET_VRING_BASE = 10,
40 	VHOST_USER_GET_VRING_BASE = 11,
41 	VHOST_USER_SET_VRING_KICK = 12,
42 	VHOST_USER_SET_VRING_CALL = 13,
43 	VHOST_USER_SET_VRING_ERR = 14,
44 	VHOST_USER_GET_PROTOCOL_FEATURES = 15,
45 	VHOST_USER_SET_PROTOCOL_FEATURES = 16,
46 	VHOST_USER_GET_QUEUE_NUM = 17,
47 	VHOST_USER_SET_VRING_ENABLE = 18,
48 	VHOST_USER_SEND_RARP = 19,
49 	VHOST_USER_NET_SEND_MTU = 20,
50 	VHOST_USER_SET_SLAVE_REQ_FD = 21,
51 	VHOST_USER_IOTLB_MSG = 22,
52 	VHOST_USER_SET_VRING_ENDIAN = 23,
53 	VHOST_USER_GET_CONFIG = 24,
54 	VHOST_USER_SET_CONFIG = 25,
55 };
56 
57 enum vhost_user_slave_request {
58 	VHOST_USER_SLAVE_IOTLB_MSG = 1,
59 	VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
60 	VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
61 };
62 
63 struct vhost_user_header {
64 	/*
65 	 * Use enum vhost_user_request for outgoing messages,
66 	 * uses enum vhost_user_slave_request for incoming ones.
67 	 */
68 	u32 request;
69 	u32 flags;
70 	u32 size;
71 } __packed;
72 
73 struct vhost_user_config {
74 	u32 offset;
75 	u32 size;
76 	u32 flags;
77 	u8 payload[0]; /* Variable length */
78 } __packed;
79 
80 struct vhost_user_vring_state {
81 	u32 index;
82 	u32 num;
83 } __packed;
84 
85 struct vhost_user_vring_addr {
86 	u32 index;
87 	u32 flags;
88 	u64 desc, used, avail, log;
89 } __packed;
90 
91 struct vhost_user_mem_region {
92 	u64 guest_addr;
93 	u64 size;
94 	u64 user_addr;
95 	u64 mmap_offset;
96 } __packed;
97 
98 struct vhost_user_mem_regions {
99 	u32 num;
100 	u32 padding;
101 	struct vhost_user_mem_region regions[2]; /* Currently supporting 2 */
102 } __packed;
103 
104 union vhost_user_payload {
105 	u64 integer;
106 	struct vhost_user_config config;
107 	struct vhost_user_vring_state vring_state;
108 	struct vhost_user_vring_addr vring_addr;
109 	struct vhost_user_mem_regions mem_regions;
110 };
111 
112 struct vhost_user_msg {
113 	struct vhost_user_header header;
114 	union vhost_user_payload payload;
115 } __packed;
116 
117 #endif
118