aboutsummaryrefslogtreecommitdiff
path: root/spice-qemu-char.c
blob: 684024bf573420207a934625a44e585a2d749b92 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
#include "config-host.h"
#include "trace.h"
#include "ui/qemu-spice.h"
#include <spice.h>
#include <spice-experimental.h>

#include "osdep.h"

#define dprintf(_scd, _level, _fmt, ...)                                \
    do {                                                                \
        static unsigned __dprintf_counter = 0;                          \
        if (_scd->debug >= _level) {                                    \
            fprintf(stderr, "scd: %3d: " _fmt, ++__dprintf_counter, ## __VA_ARGS__);\
        }                                                               \
    } while (0)

#define VMC_MAX_HOST_WRITE    2048

typedef struct SpiceCharDriver {
    CharDriverState*      chr;
    SpiceCharDeviceInstance     sin;
    char                  *subtype;
    bool                  active;
    uint8_t               *buffer;
    uint8_t               *datapos;
    ssize_t               bufsize, datalen;
    uint32_t              debug;
} SpiceCharDriver;

static int vmc_write(SpiceCharDeviceInstance *sin, const uint8_t *buf, int len)
{
    SpiceCharDriver *scd = container_of(sin, SpiceCharDriver, sin);
    ssize_t out = 0;
    ssize_t last_out;
    uint8_t* p = (uint8_t*)buf;

    while (len > 0) {
        last_out = MIN(len, VMC_MAX_HOST_WRITE);
        if (qemu_chr_can_read(scd->chr) < last_out) {
            break;
        }
        qemu_chr_read(scd->chr, p, last_out);
        out += last_out;
        len -= last_out;
        p += last_out;
    }

    dprintf(scd, 3, "%s: %lu/%zd\n", __func__, out, len + out);
    trace_spice_vmc_write(out, len + out);
    return out;
}

static int vmc_read(SpiceCharDeviceInstance *sin, uint8_t *buf, int len)
{
    SpiceCharDriver *scd = container_of(sin, SpiceCharDriver, sin);
    int bytes = MIN(len, scd->datalen);

    dprintf(scd, 2, "%s: %p %d/%d/%zd\n", __func__, scd->datapos, len, bytes, scd->datalen);
    if (bytes > 0) {
        memcpy(buf, scd->datapos, bytes);
        scd->datapos += bytes;
        scd->datalen -= bytes;
        assert(scd->datalen >= 0);
        if (scd->datalen == 0) {
            scd->datapos = 0;
        }
    }
    trace_spice_vmc_read(bytes, len);
    return bytes;
}

static SpiceCharDeviceInterface vmc_interface = {
    .base.type          = SPICE_INTERFACE_CHAR_DEVICE,
    .base.description   = "spice virtual channel char device",
    .base.major_version = SPICE_INTERFACE_CHAR_DEVICE_MAJOR,
    .base.minor_version = SPICE_INTERFACE_CHAR_DEVICE_MINOR,
    .write              = vmc_write,
    .read               = vmc_read,
};


static void vmc_register_interface(SpiceCharDriver *scd)
{
    if (scd->active) {
        return;
    }
    dprintf(scd, 1, "%s\n", __func__);
    scd->sin.base.sif = &vmc_interface.base;
    qemu_spice_add_interface(&scd->sin.base);
    scd->active = true;
    trace_spice_vmc_register_interface(scd);
}

static void vmc_unregister_interface(SpiceCharDriver *scd)
{
    if (!scd->active) {
        return;
    }
    dprintf(scd, 1, "%s\n", __func__);
    spice_server_remove_interface(&scd->sin.base);
    scd->active = false;
    trace_spice_vmc_unregister_interface(scd);
}


static int spice_chr_write(CharDriverState *chr, const uint8_t *buf, int len)
{
    SpiceCharDriver *s = chr->opaque;

    dprintf(s, 2, "%s: %d\n", __func__, len);
    vmc_register_interface(s);
    assert(s->datalen == 0);
    if (s->bufsize < len) {
        s->bufsize = len;
        s->buffer = g_realloc(s->buffer, s->bufsize);
    }
    memcpy(s->buffer, buf, len);
    s->datapos = s->buffer;
    s->datalen = len;
    spice_server_char_device_wakeup(&s->sin);
    return len;
}

static void spice_chr_close(struct CharDriverState *chr)
{
    SpiceCharDriver *s = chr->opaque;

    printf("%s\n", __func__);
    vmc_unregister_interface(s);
    g_free(s);
}

static void spice_chr_guest_open(struct CharDriverState *chr)
{
    SpiceCharDriver *s = chr->opaque;
    vmc_register_interface(s);
}

static void spice_chr_guest_close(struct CharDriverState *chr)
{
    SpiceCharDriver *s = chr->opaque;
    vmc_unregister_interface(s);
}

static void print_allowed_subtypes(void)
{
    const char** psubtype;
    int i;

    fprintf(stderr, "allowed names: ");
    for(i=0, psubtype = spice_server_char_device_recognized_subtypes();
        *psubtype != NULL; ++psubtype, ++i) {
        if (i == 0) {
            fprintf(stderr, "%s", *psubtype);
        } else {
            fprintf(stderr, ", %s", *psubtype);
        }
    }
    fprintf(stderr, "\n");
}

int qemu_chr_open_spice(QemuOpts *opts, CharDriverState **_chr)
{
    CharDriverState *chr;
    SpiceCharDriver *s;
    const char* name = qemu_opt_get(opts, "name");
    uint32_t debug = qemu_opt_get_number(opts, "debug", 0);
    const char** psubtype = spice_server_char_device_recognized_subtypes();
    const char *subtype = NULL;

    if (name == NULL) {
        fprintf(stderr, "spice-qemu-char: missing name parameter\n");
        print_allowed_subtypes();
        return -EINVAL;
    }
    for(;*psubtype != NULL; ++psubtype) {
        if (strcmp(name, *psubtype) == 0) {
            subtype = *psubtype;
            break;
        }
    }
    if (subtype == NULL) {
        fprintf(stderr, "spice-qemu-char: unsupported name\n");
        print_allowed_subtypes();
        return -EINVAL;
    }

    chr = g_malloc0(sizeof(CharDriverState));
    s = g_malloc0(sizeof(SpiceCharDriver));
    s->chr = chr;
    s->debug = debug;
    s->active = false;
    s->sin.subtype = subtype;
    chr->opaque = s;
    chr->chr_write = spice_chr_write;
    chr->chr_close = spice_chr_close;
    chr->chr_guest_open = spice_chr_guest_open;
    chr->chr_guest_close = spice_chr_guest_close;

    qemu_chr_generic_open(chr);

    *_chr = chr;
    return 0;
}