xref: /openbmc/qemu/include/hw/remote/mpqemu-link.h (revision ffe98631)
1 /*
2  * Communication channel between QEMU and remote device process
3  *
4  * Copyright © 2018, 2021 Oracle and/or its affiliates.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  *
9  */
10 
11 #ifndef MPQEMU_LINK_H
12 #define MPQEMU_LINK_H
13 
14 #include "qom/object.h"
15 #include "qemu/thread.h"
16 #include "io/channel.h"
17 #include "exec/hwaddr.h"
18 #include "io/channel-socket.h"
19 #include "hw/remote/proxy.h"
20 
21 #define REMOTE_MAX_FDS 8
22 
23 #define MPQEMU_MSG_HDR_SIZE offsetof(MPQemuMsg, data.u64)
24 
25 /**
26  * MPQemuCmd:
27  *
28  * MPQemuCmd enum type to specify the command to be executed on the remote
29  * device.
30  *
31  * This uses a private protocol between QEMU and the remote process. vfio-user
32  * protocol would supersede this in the future.
33  *
34  */
35 typedef enum {
36     MPQEMU_CMD_SYNC_SYSMEM,
37     MPQEMU_CMD_RET,
38     MPQEMU_CMD_PCI_CFGWRITE,
39     MPQEMU_CMD_PCI_CFGREAD,
40     MPQEMU_CMD_BAR_WRITE,
41     MPQEMU_CMD_BAR_READ,
42     MPQEMU_CMD_SET_IRQFD,
43     MPQEMU_CMD_DEVICE_RESET,
44     MPQEMU_CMD_MAX,
45 } MPQemuCmd;
46 
47 typedef struct {
48     hwaddr gpas[REMOTE_MAX_FDS];
49     uint64_t sizes[REMOTE_MAX_FDS];
50     off_t offsets[REMOTE_MAX_FDS];
51 } SyncSysmemMsg;
52 
53 typedef struct {
54     uint32_t addr;
55     uint32_t val;
56     int len;
57 } PciConfDataMsg;
58 
59 typedef struct {
60     hwaddr addr;
61     uint64_t val;
62     unsigned size;
63     bool memory;
64 } BarAccessMsg;
65 
66 /**
67  * MPQemuMsg:
68  * @cmd: The remote command
69  * @size: Size of the data to be shared
70  * @data: Structured data
71  * @fds: File descriptors to be shared with remote device
72  *
73  * MPQemuMsg Format of the message sent to the remote device from QEMU.
74  *
75  */
76 
77 typedef struct {
78     int cmd;
79     size_t size;
80 
81     union {
82         uint64_t u64;
83         PciConfDataMsg pci_conf_data;
84         SyncSysmemMsg sync_sysmem;
85         BarAccessMsg bar_access;
86     } data;
87 
88     int fds[REMOTE_MAX_FDS];
89     int num_fds;
90 } MPQemuMsg;
91 
92 bool mpqemu_msg_send(MPQemuMsg *msg, QIOChannel *ioc, Error **errp);
93 bool mpqemu_msg_recv(MPQemuMsg *msg, QIOChannel *ioc, Error **errp);
94 
95 uint64_t mpqemu_msg_send_and_await_reply(MPQemuMsg *msg, PCIProxyDev *pdev,
96                                          Error **errp);
97 bool mpqemu_msg_valid(MPQemuMsg *msg);
98 
99 #endif
100