qemu/spice-qemu-char.c
Daniel P. Berrange d0d7708ba2 qemu-char: add logfile facility to all chardev backends
Typically a UNIX guest OS will log boot messages to a serial
port in addition to any graphical console. An admin user
may also wish to use the serial port for an interactive
console. A virtualization management system may wish to
collect system boot messages by logging the serial port,
but also wish to allow admins interactive access.

Currently providing such a feature forces the mgmt app
to either provide 2 separate serial ports, one for
logging boot messages and one for interactive console
login, or to proxy all output via a separate service
that can multiplex the two needs onto one serial port.
While both are valid approaches, they each have their
own downsides. The former causes confusion and extra
setup work for VM admins creating disk images. The latter
places an extra burden to re-implement much of the QEMU
chardev backends logic in libvirt or even higher level
mgmt apps and adds extra hops in the data transfer path.

A simpler approach that is satisfactory for many use
cases is to allow the QEMU chardev backends to have a
"logfile" property associated with them.

 $QEMU -chardev socket,host=localhost,port=9000,\
                server=on,nowait,id-charserial0,\
		logfile=/var/log/libvirt/qemu/test-serial0.log
       -device isa-serial,chardev=charserial0,id=serial0

This patch introduces a 'ChardevCommon' struct which
is setup as a base for all the ChardevBackend types.
Ideally this would be registered directly as a base
against ChardevBackend, rather than each type, but
the QAPI generator doesn't allow that since the
ChardevBackend is a non-discriminated union. The
ChardevCommon struct provides the optional 'logfile'
parameter, as well as 'logappend' which controls
whether QEMU truncates or appends (default truncate).

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1452516281-27519-1-git-send-email-berrange@redhat.com>
[Call qemu_chr_parse_common if cd->parse is NULL. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-15 18:58:02 +01:00

401 lines
11 KiB
C

#include "config-host.h"
#include "trace.h"
#include "ui/qemu-spice.h"
#include "sysemu/char.h"
#include <spice.h>
#include <spice/protocol.h>
#include "qemu/osdep.h"
typedef struct SpiceCharDriver {
CharDriverState* chr;
SpiceCharDeviceInstance sin;
bool active;
bool blocked;
const uint8_t *datapos;
int datalen;
QLIST_ENTRY(SpiceCharDriver) next;
} SpiceCharDriver;
typedef struct SpiceCharSource {
GSource source;
SpiceCharDriver *scd;
} SpiceCharSource;
static QLIST_HEAD(, SpiceCharDriver) spice_chars =
QLIST_HEAD_INITIALIZER(spice_chars);
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) {
int can_write = qemu_chr_be_can_write(scd->chr);
last_out = MIN(len, can_write);
if (last_out <= 0) {
break;
}
qemu_chr_be_write(scd->chr, p, last_out);
out += last_out;
len -= last_out;
p += last_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);
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;
scd->blocked = false;
}
trace_spice_vmc_read(bytes, len);
return bytes;
}
#if SPICE_SERVER_VERSION >= 0x000c02
static void vmc_event(SpiceCharDeviceInstance *sin, uint8_t event)
{
SpiceCharDriver *scd = container_of(sin, SpiceCharDriver, sin);
int chr_event;
switch (event) {
case SPICE_PORT_EVENT_BREAK:
chr_event = CHR_EVENT_BREAK;
break;
default:
return;
}
trace_spice_vmc_event(chr_event);
qemu_chr_be_event(scd->chr, chr_event);
}
#endif
static void vmc_state(SpiceCharDeviceInstance *sin, int connected)
{
SpiceCharDriver *scd = container_of(sin, SpiceCharDriver, sin);
if ((scd->chr->be_open && connected) ||
(!scd->chr->be_open && !connected)) {
return;
}
qemu_chr_be_event(scd->chr,
connected ? CHR_EVENT_OPENED : CHR_EVENT_CLOSED);
}
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,
.state = vmc_state,
.write = vmc_write,
.read = vmc_read,
#if SPICE_SERVER_VERSION >= 0x000c02
.event = vmc_event,
#endif
#if SPICE_SERVER_VERSION >= 0x000c06
.flags = SPICE_CHAR_DEVICE_NOTIFY_WRITABLE,
#endif
};
static void vmc_register_interface(SpiceCharDriver *scd)
{
if (scd->active) {
return;
}
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;
}
spice_server_remove_interface(&scd->sin.base);
scd->active = false;
trace_spice_vmc_unregister_interface(scd);
}
static gboolean spice_char_source_prepare(GSource *source, gint *timeout)
{
SpiceCharSource *src = (SpiceCharSource *)source;
*timeout = -1;
return !src->scd->blocked;
}
static gboolean spice_char_source_check(GSource *source)
{
SpiceCharSource *src = (SpiceCharSource *)source;
return !src->scd->blocked;
}
static gboolean spice_char_source_dispatch(GSource *source,
GSourceFunc callback, gpointer user_data)
{
GIOFunc func = (GIOFunc)callback;
return func(NULL, G_IO_OUT, user_data);
}
static GSourceFuncs SpiceCharSourceFuncs = {
.prepare = spice_char_source_prepare,
.check = spice_char_source_check,
.dispatch = spice_char_source_dispatch,
};
static GSource *spice_chr_add_watch(CharDriverState *chr, GIOCondition cond)
{
SpiceCharDriver *scd = chr->opaque;
SpiceCharSource *src;
assert(cond & G_IO_OUT);
src = (SpiceCharSource *)g_source_new(&SpiceCharSourceFuncs,
sizeof(SpiceCharSource));
src->scd = scd;
return (GSource *)src;
}
static int spice_chr_write(CharDriverState *chr, const uint8_t *buf, int len)
{
SpiceCharDriver *s = chr->opaque;
int read_bytes;
assert(s->datalen == 0);
s->datapos = buf;
s->datalen = len;
spice_server_char_device_wakeup(&s->sin);
read_bytes = len - s->datalen;
if (read_bytes != len) {
/* We'll get passed in the unconsumed data with the next call */
s->datalen = 0;
s->datapos = NULL;
s->blocked = true;
}
return read_bytes;
}
static void spice_chr_close(struct CharDriverState *chr)
{
SpiceCharDriver *s = chr->opaque;
vmc_unregister_interface(s);
QLIST_REMOVE(s, next);
g_free((char *)s->sin.subtype);
#if SPICE_SERVER_VERSION >= 0x000c02
g_free((char *)s->sin.portname);
#endif
g_free(s);
}
static void spice_vmc_set_fe_open(struct CharDriverState *chr, int fe_open)
{
SpiceCharDriver *s = chr->opaque;
if (fe_open) {
vmc_register_interface(s);
} else {
vmc_unregister_interface(s);
}
}
static void spice_port_set_fe_open(struct CharDriverState *chr, int fe_open)
{
#if SPICE_SERVER_VERSION >= 0x000c02
SpiceCharDriver *s = chr->opaque;
if (fe_open) {
spice_server_port_event(&s->sin, SPICE_PORT_EVENT_OPENED);
} else {
spice_server_port_event(&s->sin, SPICE_PORT_EVENT_CLOSED);
}
#endif
}
static void spice_chr_fe_event(struct CharDriverState *chr, int event)
{
#if SPICE_SERVER_VERSION >= 0x000c02
SpiceCharDriver *s = chr->opaque;
spice_server_port_event(&s->sin, event);
#endif
}
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");
}
static void spice_chr_accept_input(struct CharDriverState *chr)
{
SpiceCharDriver *s = chr->opaque;
spice_server_char_device_wakeup(&s->sin);
}
static CharDriverState *chr_open(const char *subtype,
void (*set_fe_open)(struct CharDriverState *,
int),
ChardevCommon *backend,
Error **errp)
{
CharDriverState *chr;
SpiceCharDriver *s;
chr = qemu_chr_alloc(backend, errp);
if (!chr) {
return NULL;
}
s = g_malloc0(sizeof(SpiceCharDriver));
s->chr = chr;
s->active = false;
s->sin.subtype = g_strdup(subtype);
chr->opaque = s;
chr->chr_write = spice_chr_write;
chr->chr_add_watch = spice_chr_add_watch;
chr->chr_close = spice_chr_close;
chr->chr_set_fe_open = set_fe_open;
chr->explicit_be_open = true;
chr->chr_fe_event = spice_chr_fe_event;
chr->chr_accept_input = spice_chr_accept_input;
QLIST_INSERT_HEAD(&spice_chars, s, next);
return chr;
}
static CharDriverState *qemu_chr_open_spice_vmc(const char *id,
ChardevBackend *backend,
ChardevReturn *ret,
Error **errp)
{
const char *type = backend->u.spicevmc->type;
const char **psubtype = spice_server_char_device_recognized_subtypes();
ChardevCommon *common = qapi_ChardevSpiceChannel_base(backend->u.spicevmc);
for (; *psubtype != NULL; ++psubtype) {
if (strcmp(type, *psubtype) == 0) {
break;
}
}
if (*psubtype == NULL) {
fprintf(stderr, "spice-qemu-char: unsupported type: %s\n", type);
print_allowed_subtypes();
return NULL;
}
return chr_open(type, spice_vmc_set_fe_open, common, errp);
}
#if SPICE_SERVER_VERSION >= 0x000c02
static CharDriverState *qemu_chr_open_spice_port(const char *id,
ChardevBackend *backend,
ChardevReturn *ret,
Error **errp)
{
const char *name = backend->u.spiceport->fqdn;
ChardevCommon *common = qapi_ChardevSpicePort_base(backend->u.spiceport);
CharDriverState *chr;
SpiceCharDriver *s;
if (name == NULL) {
fprintf(stderr, "spice-qemu-char: missing name parameter\n");
return NULL;
}
chr = chr_open("port", spice_port_set_fe_open, common, errp);
if (!chr) {
return NULL;
}
s = chr->opaque;
s->sin.portname = g_strdup(name);
return chr;
}
void qemu_spice_register_ports(void)
{
SpiceCharDriver *s;
QLIST_FOREACH(s, &spice_chars, next) {
if (s->sin.portname == NULL) {
continue;
}
vmc_register_interface(s);
}
}
#endif
static void qemu_chr_parse_spice_vmc(QemuOpts *opts, ChardevBackend *backend,
Error **errp)
{
const char *name = qemu_opt_get(opts, "name");
if (name == NULL) {
error_setg(errp, "chardev: spice channel: no name given");
return;
}
backend->u.spicevmc = g_new0(ChardevSpiceChannel, 1);
backend->u.spicevmc->type = g_strdup(name);
}
static void qemu_chr_parse_spice_port(QemuOpts *opts, ChardevBackend *backend,
Error **errp)
{
const char *name = qemu_opt_get(opts, "name");
if (name == NULL) {
error_setg(errp, "chardev: spice port: no name given");
return;
}
backend->u.spiceport = g_new0(ChardevSpicePort, 1);
backend->u.spiceport->fqdn = g_strdup(name);
}
static void register_types(void)
{
register_char_driver("spicevmc", CHARDEV_BACKEND_KIND_SPICEVMC,
qemu_chr_parse_spice_vmc, qemu_chr_open_spice_vmc);
register_char_driver("spiceport", CHARDEV_BACKEND_KIND_SPICEPORT,
qemu_chr_parse_spice_port, qemu_chr_open_spice_port);
}
type_init(register_types);