xref: /linux/arch/um/drivers/vhost_user.h (revision 4b4193256c8d3bc3a5397b5cd9494c2ad386317d)
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 #define VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS	14
17 /* Vring state index masks */
18 #define VHOST_USER_VRING_INDEX_MASK	0xff
19 #define VHOST_USER_VRING_POLL_MASK	BIT(8)
20 
21 /* Supported version */
22 #define VHOST_USER_VERSION		1
23 /* Supported transport features */
24 #define VHOST_USER_SUPPORTED_F		BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES)
25 /* Supported protocol features */
26 #define VHOST_USER_SUPPORTED_PROTOCOL_F	(BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
27 					 BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ) | \
28 					 BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG) | \
29 					 BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS))
30 
31 enum vhost_user_request {
32 	VHOST_USER_GET_FEATURES = 1,
33 	VHOST_USER_SET_FEATURES = 2,
34 	VHOST_USER_SET_OWNER = 3,
35 	VHOST_USER_RESET_OWNER = 4,
36 	VHOST_USER_SET_MEM_TABLE = 5,
37 	VHOST_USER_SET_LOG_BASE = 6,
38 	VHOST_USER_SET_LOG_FD = 7,
39 	VHOST_USER_SET_VRING_NUM = 8,
40 	VHOST_USER_SET_VRING_ADDR = 9,
41 	VHOST_USER_SET_VRING_BASE = 10,
42 	VHOST_USER_GET_VRING_BASE = 11,
43 	VHOST_USER_SET_VRING_KICK = 12,
44 	VHOST_USER_SET_VRING_CALL = 13,
45 	VHOST_USER_SET_VRING_ERR = 14,
46 	VHOST_USER_GET_PROTOCOL_FEATURES = 15,
47 	VHOST_USER_SET_PROTOCOL_FEATURES = 16,
48 	VHOST_USER_GET_QUEUE_NUM = 17,
49 	VHOST_USER_SET_VRING_ENABLE = 18,
50 	VHOST_USER_SEND_RARP = 19,
51 	VHOST_USER_NET_SEND_MTU = 20,
52 	VHOST_USER_SET_SLAVE_REQ_FD = 21,
53 	VHOST_USER_IOTLB_MSG = 22,
54 	VHOST_USER_SET_VRING_ENDIAN = 23,
55 	VHOST_USER_GET_CONFIG = 24,
56 	VHOST_USER_SET_CONFIG = 25,
57 	VHOST_USER_VRING_KICK = 35,
58 };
59 
60 enum vhost_user_slave_request {
61 	VHOST_USER_SLAVE_IOTLB_MSG = 1,
62 	VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
63 	VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
64 	VHOST_USER_SLAVE_VRING_CALL = 4,
65 };
66 
67 struct vhost_user_header {
68 	/*
69 	 * Use enum vhost_user_request for outgoing messages,
70 	 * uses enum vhost_user_slave_request for incoming ones.
71 	 */
72 	u32 request;
73 	u32 flags;
74 	u32 size;
75 } __packed;
76 
77 struct vhost_user_config {
78 	u32 offset;
79 	u32 size;
80 	u32 flags;
81 	u8 payload[]; /* Variable length */
82 } __packed;
83 
84 struct vhost_user_vring_state {
85 	u32 index;
86 	u32 num;
87 } __packed;
88 
89 struct vhost_user_vring_addr {
90 	u32 index;
91 	u32 flags;
92 	u64 desc, used, avail, log;
93 } __packed;
94 
95 struct vhost_user_mem_region {
96 	u64 guest_addr;
97 	u64 size;
98 	u64 user_addr;
99 	u64 mmap_offset;
100 } __packed;
101 
102 struct vhost_user_mem_regions {
103 	u32 num;
104 	u32 padding;
105 	struct vhost_user_mem_region regions[2]; /* Currently supporting 2 */
106 } __packed;
107 
108 union vhost_user_payload {
109 	u64 integer;
110 	struct vhost_user_config config;
111 	struct vhost_user_vring_state vring_state;
112 	struct vhost_user_vring_addr vring_addr;
113 	struct vhost_user_mem_regions mem_regions;
114 };
115 
116 struct vhost_user_msg {
117 	struct vhost_user_header header;
118 	union vhost_user_payload payload;
119 } __packed;
120 
121 #endif
122