qemu/qemu-config.c
Stefan Hajnoczi 92196b2f56 block: add cache=directsync parameter to -drive
This patch adds -drive cache=directsync for O_DIRECT | O_SYNC host file
I/O with no disk write cache presented to the guest.

This mode is useful when guests may not be sending flushes when
appropriate and therefore leave data at risk in case of power failure.
When cache=directsync is used, write operations are only completed to
the guest when data is safely on disk.

This new mode is like cache=writethrough but it bypasses the host page
cache.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23 14:15:17 +02:00

732 lines
18 KiB
C

#include "qemu-common.h"
#include "qemu-error.h"
#include "qemu-option.h"
#include "qemu-config.h"
#include "hw/qdev.h"
static QemuOptsList qemu_drive_opts = {
.name = "drive",
.head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
.desc = {
{
.name = "bus",
.type = QEMU_OPT_NUMBER,
.help = "bus number",
},{
.name = "unit",
.type = QEMU_OPT_NUMBER,
.help = "unit number (i.e. lun for scsi)",
},{
.name = "if",
.type = QEMU_OPT_STRING,
.help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
},{
.name = "index",
.type = QEMU_OPT_NUMBER,
.help = "index number",
},{
.name = "cyls",
.type = QEMU_OPT_NUMBER,
.help = "number of cylinders (ide disk geometry)",
},{
.name = "heads",
.type = QEMU_OPT_NUMBER,
.help = "number of heads (ide disk geometry)",
},{
.name = "secs",
.type = QEMU_OPT_NUMBER,
.help = "number of sectors (ide disk geometry)",
},{
.name = "trans",
.type = QEMU_OPT_STRING,
.help = "chs translation (auto, lba. none)",
},{
.name = "media",
.type = QEMU_OPT_STRING,
.help = "media type (disk, cdrom)",
},{
.name = "snapshot",
.type = QEMU_OPT_BOOL,
.help = "enable/disable snapshot mode",
},{
.name = "file",
.type = QEMU_OPT_STRING,
.help = "disk image",
},{
.name = "cache",
.type = QEMU_OPT_STRING,
.help = "host cache usage (none, writeback, writethrough, "
"directsync, unsafe)",
},{
.name = "aio",
.type = QEMU_OPT_STRING,
.help = "host AIO implementation (threads, native)",
},{
.name = "format",
.type = QEMU_OPT_STRING,
.help = "disk format (raw, qcow2, ...)",
},{
.name = "serial",
.type = QEMU_OPT_STRING,
.help = "disk serial number",
},{
.name = "rerror",
.type = QEMU_OPT_STRING,
.help = "read error action",
},{
.name = "werror",
.type = QEMU_OPT_STRING,
.help = "write error action",
},{
.name = "addr",
.type = QEMU_OPT_STRING,
.help = "pci address (virtio only)",
},{
.name = "readonly",
.type = QEMU_OPT_BOOL,
.help = "open drive file as read-only",
},
{ /* end of list */ }
},
};
static QemuOptsList qemu_chardev_opts = {
.name = "chardev",
.implied_opt_name = "backend",
.head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
.desc = {
{
.name = "backend",
.type = QEMU_OPT_STRING,
},{
.name = "path",
.type = QEMU_OPT_STRING,
},{
.name = "host",
.type = QEMU_OPT_STRING,
},{
.name = "port",
.type = QEMU_OPT_STRING,
},{
.name = "localaddr",
.type = QEMU_OPT_STRING,
},{
.name = "localport",
.type = QEMU_OPT_STRING,
},{
.name = "to",
.type = QEMU_OPT_NUMBER,
},{
.name = "ipv4",
.type = QEMU_OPT_BOOL,
},{
.name = "ipv6",
.type = QEMU_OPT_BOOL,
},{
.name = "wait",
.type = QEMU_OPT_BOOL,
},{
.name = "server",
.type = QEMU_OPT_BOOL,
},{
.name = "delay",
.type = QEMU_OPT_BOOL,
},{
.name = "telnet",
.type = QEMU_OPT_BOOL,
},{
.name = "width",
.type = QEMU_OPT_NUMBER,
},{
.name = "height",
.type = QEMU_OPT_NUMBER,
},{
.name = "cols",
.type = QEMU_OPT_NUMBER,
},{
.name = "rows",
.type = QEMU_OPT_NUMBER,
},{
.name = "mux",
.type = QEMU_OPT_BOOL,
},{
.name = "signal",
.type = QEMU_OPT_BOOL,
},{
.name = "name",
.type = QEMU_OPT_STRING,
},{
.name = "debug",
.type = QEMU_OPT_NUMBER,
},
{ /* end of list */ }
},
};
QemuOptsList qemu_fsdev_opts = {
.name = "fsdev",
.implied_opt_name = "fstype",
.head = QTAILQ_HEAD_INITIALIZER(qemu_fsdev_opts.head),
.desc = {
{
.name = "fstype",
.type = QEMU_OPT_STRING,
}, {
.name = "path",
.type = QEMU_OPT_STRING,
}, {
.name = "security_model",
.type = QEMU_OPT_STRING,
},
{ /*End of list */ }
},
};
QemuOptsList qemu_virtfs_opts = {
.name = "virtfs",
.implied_opt_name = "fstype",
.head = QTAILQ_HEAD_INITIALIZER(qemu_virtfs_opts.head),
.desc = {
{
.name = "fstype",
.type = QEMU_OPT_STRING,
}, {
.name = "path",
.type = QEMU_OPT_STRING,
}, {
.name = "mount_tag",
.type = QEMU_OPT_STRING,
}, {
.name = "security_model",
.type = QEMU_OPT_STRING,
},
{ /*End of list */ }
},
};
static QemuOptsList qemu_device_opts = {
.name = "device",
.implied_opt_name = "driver",
.head = QTAILQ_HEAD_INITIALIZER(qemu_device_opts.head),
.desc = {
/*
* no elements => accept any
* sanity checking will happen later
* when setting device properties
*/
{ /* end of list */ }
},
};
static QemuOptsList qemu_netdev_opts = {
.name = "netdev",
.implied_opt_name = "type",
.head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
.desc = {
/*
* no elements => accept any params
* validation will happen later
*/
{ /* end of list */ }
},
};
static QemuOptsList qemu_net_opts = {
.name = "net",
.implied_opt_name = "type",
.head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
.desc = {
/*
* no elements => accept any params
* validation will happen later
*/
{ /* end of list */ }
},
};
static QemuOptsList qemu_rtc_opts = {
.name = "rtc",
.head = QTAILQ_HEAD_INITIALIZER(qemu_rtc_opts.head),
.desc = {
{
.name = "base",
.type = QEMU_OPT_STRING,
},{
.name = "clock",
.type = QEMU_OPT_STRING,
},{
.name = "driftfix",
.type = QEMU_OPT_STRING,
},
{ /* end of list */ }
},
};
static QemuOptsList qemu_global_opts = {
.name = "global",
.head = QTAILQ_HEAD_INITIALIZER(qemu_global_opts.head),
.desc = {
{
.name = "driver",
.type = QEMU_OPT_STRING,
},{
.name = "property",
.type = QEMU_OPT_STRING,
},{
.name = "value",
.type = QEMU_OPT_STRING,
},
{ /* end of list */ }
},
};
static QemuOptsList qemu_mon_opts = {
.name = "mon",
.implied_opt_name = "chardev",
.head = QTAILQ_HEAD_INITIALIZER(qemu_mon_opts.head),
.desc = {
{
.name = "mode",
.type = QEMU_OPT_STRING,
},{
.name = "chardev",
.type = QEMU_OPT_STRING,
},{
.name = "default",
.type = QEMU_OPT_BOOL,
},{
.name = "pretty",
.type = QEMU_OPT_BOOL,
},
{ /* end of list */ }
},
};
#ifdef CONFIG_SIMPLE_TRACE
static QemuOptsList qemu_trace_opts = {
.name = "trace",
.implied_opt_name = "trace",
.head = QTAILQ_HEAD_INITIALIZER(qemu_trace_opts.head),
.desc = {
{
.name = "file",
.type = QEMU_OPT_STRING,
},
{ /* end of list */ }
},
};
#endif
static QemuOptsList qemu_cpudef_opts = {
.name = "cpudef",
.head = QTAILQ_HEAD_INITIALIZER(qemu_cpudef_opts.head),
.desc = {
{
.name = "name",
.type = QEMU_OPT_STRING,
},{
.name = "level",
.type = QEMU_OPT_NUMBER,
},{
.name = "vendor",
.type = QEMU_OPT_STRING,
},{
.name = "family",
.type = QEMU_OPT_NUMBER,
},{
.name = "model",
.type = QEMU_OPT_NUMBER,
},{
.name = "stepping",
.type = QEMU_OPT_NUMBER,
},{
.name = "feature_edx", /* cpuid 0000_0001.edx */
.type = QEMU_OPT_STRING,
},{
.name = "feature_ecx", /* cpuid 0000_0001.ecx */
.type = QEMU_OPT_STRING,
},{
.name = "extfeature_edx", /* cpuid 8000_0001.edx */
.type = QEMU_OPT_STRING,
},{
.name = "extfeature_ecx", /* cpuid 8000_0001.ecx */
.type = QEMU_OPT_STRING,
},{
.name = "xlevel",
.type = QEMU_OPT_NUMBER,
},{
.name = "model_id",
.type = QEMU_OPT_STRING,
},{
.name = "vendor_override",
.type = QEMU_OPT_NUMBER,
},
{ /* end of list */ }
},
};
QemuOptsList qemu_spice_opts = {
.name = "spice",
.head = QTAILQ_HEAD_INITIALIZER(qemu_spice_opts.head),
.desc = {
{
.name = "port",
.type = QEMU_OPT_NUMBER,
},{
.name = "tls-port",
.type = QEMU_OPT_NUMBER,
},{
.name = "addr",
.type = QEMU_OPT_STRING,
},{
.name = "ipv4",
.type = QEMU_OPT_BOOL,
},{
.name = "ipv6",
.type = QEMU_OPT_BOOL,
},{
.name = "password",
.type = QEMU_OPT_STRING,
},{
.name = "disable-ticketing",
.type = QEMU_OPT_BOOL,
},{
.name = "disable-copy-paste",
.type = QEMU_OPT_BOOL,
},{
.name = "sasl",
.type = QEMU_OPT_BOOL,
},{
.name = "x509-dir",
.type = QEMU_OPT_STRING,
},{
.name = "x509-key-file",
.type = QEMU_OPT_STRING,
},{
.name = "x509-key-password",
.type = QEMU_OPT_STRING,
},{
.name = "x509-cert-file",
.type = QEMU_OPT_STRING,
},{
.name = "x509-cacert-file",
.type = QEMU_OPT_STRING,
},{
.name = "x509-dh-key-file",
.type = QEMU_OPT_STRING,
},{
.name = "tls-ciphers",
.type = QEMU_OPT_STRING,
},{
.name = "tls-channel",
.type = QEMU_OPT_STRING,
},{
.name = "plaintext-channel",
.type = QEMU_OPT_STRING,
},{
.name = "image-compression",
.type = QEMU_OPT_STRING,
},{
.name = "jpeg-wan-compression",
.type = QEMU_OPT_STRING,
},{
.name = "zlib-glz-wan-compression",
.type = QEMU_OPT_STRING,
},{
.name = "streaming-video",
.type = QEMU_OPT_STRING,
},{
.name = "agent-mouse",
.type = QEMU_OPT_BOOL,
},{
.name = "playback-compression",
.type = QEMU_OPT_BOOL,
},
{ /* end of list */ }
},
};
QemuOptsList qemu_option_rom_opts = {
.name = "option-rom",
.implied_opt_name = "romfile",
.head = QTAILQ_HEAD_INITIALIZER(qemu_option_rom_opts.head),
.desc = {
{
.name = "bootindex",
.type = QEMU_OPT_NUMBER,
}, {
.name = "romfile",
.type = QEMU_OPT_STRING,
},
{ /* end of list */ }
},
};
static QemuOptsList qemu_machine_opts = {
.name = "machine",
.implied_opt_name = "type",
.head = QTAILQ_HEAD_INITIALIZER(qemu_machine_opts.head),
.desc = {
{
.name = "type",
.type = QEMU_OPT_STRING,
.help = "emulated machine"
}, {
.name = "accel",
.type = QEMU_OPT_STRING,
.help = "accelerator list",
},
{ /* End of list */ }
},
};
QemuOptsList qemu_boot_opts = {
.name = "boot-opts",
.head = QTAILQ_HEAD_INITIALIZER(qemu_boot_opts.head),
.desc = {
/* the three names below are not used now */
{
.name = "order",
.type = QEMU_OPT_STRING,
}, {
.name = "once",
.type = QEMU_OPT_STRING,
}, {
.name = "menu",
.type = QEMU_OPT_STRING,
/* following are really used */
}, {
.name = "splash",
.type = QEMU_OPT_STRING,
}, {
.name = "splash-time",
.type = QEMU_OPT_STRING,
},
{ /*End of list */ }
},
};
static QemuOptsList *vm_config_groups[32] = {
&qemu_drive_opts,
&qemu_chardev_opts,
&qemu_device_opts,
&qemu_netdev_opts,
&qemu_net_opts,
&qemu_rtc_opts,
&qemu_global_opts,
&qemu_mon_opts,
&qemu_cpudef_opts,
#ifdef CONFIG_SIMPLE_TRACE
&qemu_trace_opts,
#endif
&qemu_option_rom_opts,
&qemu_machine_opts,
&qemu_boot_opts,
NULL,
};
static QemuOptsList *find_list(QemuOptsList **lists, const char *group)
{
int i;
for (i = 0; lists[i] != NULL; i++) {
if (strcmp(lists[i]->name, group) == 0)
break;
}
if (lists[i] == NULL) {
error_report("there is no option group \"%s\"", group);
}
return lists[i];
}
QemuOptsList *qemu_find_opts(const char *group)
{
return find_list(vm_config_groups, group);
}
void qemu_add_opts(QemuOptsList *list)
{
int entries, i;
entries = ARRAY_SIZE(vm_config_groups);
entries--; /* keep list NULL terminated */
for (i = 0; i < entries; i++) {
if (vm_config_groups[i] == NULL) {
vm_config_groups[i] = list;
return;
}
}
fprintf(stderr, "ran out of space in vm_config_groups");
abort();
}
int qemu_set_option(const char *str)
{
char group[64], id[64], arg[64];
QemuOptsList *list;
QemuOpts *opts;
int rc, offset;
rc = sscanf(str, "%63[^.].%63[^.].%63[^=]%n", group, id, arg, &offset);
if (rc < 3 || str[offset] != '=') {
error_report("can't parse: \"%s\"", str);
return -1;
}
list = qemu_find_opts(group);
if (list == NULL) {
return -1;
}
opts = qemu_opts_find(list, id);
if (!opts) {
error_report("there is no %s \"%s\" defined",
list->name, id);
return -1;
}
if (qemu_opt_set(opts, arg, str+offset+1) == -1) {
return -1;
}
return 0;
}
int qemu_global_option(const char *str)
{
char driver[64], property[64];
QemuOpts *opts;
int rc, offset;
rc = sscanf(str, "%63[^.].%63[^=]%n", driver, property, &offset);
if (rc < 2 || str[offset] != '=') {
error_report("can't parse: \"%s\"", str);
return -1;
}
opts = qemu_opts_create(&qemu_global_opts, NULL, 0);
qemu_opt_set(opts, "driver", driver);
qemu_opt_set(opts, "property", property);
qemu_opt_set(opts, "value", str+offset+1);
return 0;
}
struct ConfigWriteData {
QemuOptsList *list;
FILE *fp;
};
static int config_write_opt(const char *name, const char *value, void *opaque)
{
struct ConfigWriteData *data = opaque;
fprintf(data->fp, " %s = \"%s\"\n", name, value);
return 0;
}
static int config_write_opts(QemuOpts *opts, void *opaque)
{
struct ConfigWriteData *data = opaque;
const char *id = qemu_opts_id(opts);
if (id) {
fprintf(data->fp, "[%s \"%s\"]\n", data->list->name, id);
} else {
fprintf(data->fp, "[%s]\n", data->list->name);
}
qemu_opt_foreach(opts, config_write_opt, data, 0);
fprintf(data->fp, "\n");
return 0;
}
void qemu_config_write(FILE *fp)
{
struct ConfigWriteData data = { .fp = fp };
QemuOptsList **lists = vm_config_groups;
int i;
fprintf(fp, "# qemu config file\n\n");
for (i = 0; lists[i] != NULL; i++) {
data.list = lists[i];
qemu_opts_foreach(data.list, config_write_opts, &data, 0);
}
}
int qemu_config_parse(FILE *fp, QemuOptsList **lists, const char *fname)
{
char line[1024], group[64], id[64], arg[64], value[1024];
Location loc;
QemuOptsList *list = NULL;
QemuOpts *opts = NULL;
int res = -1, lno = 0;
loc_push_none(&loc);
while (fgets(line, sizeof(line), fp) != NULL) {
loc_set_file(fname, ++lno);
if (line[0] == '\n') {
/* skip empty lines */
continue;
}
if (line[0] == '#') {
/* comment */
continue;
}
if (sscanf(line, "[%63s \"%63[^\"]\"]", group, id) == 2) {
/* group with id */
list = find_list(lists, group);
if (list == NULL)
goto out;
opts = qemu_opts_create(list, id, 1);
continue;
}
if (sscanf(line, "[%63[^]]]", group) == 1) {
/* group without id */
list = find_list(lists, group);
if (list == NULL)
goto out;
opts = qemu_opts_create(list, NULL, 0);
continue;
}
if (sscanf(line, " %63s = \"%1023[^\"]\"", arg, value) == 2) {
/* arg = value */
if (opts == NULL) {
error_report("no group defined");
goto out;
}
if (qemu_opt_set(opts, arg, value) != 0) {
goto out;
}
continue;
}
error_report("parse error");
goto out;
}
if (ferror(fp)) {
error_report("error reading file");
goto out;
}
res = 0;
out:
loc_pop(&loc);
return res;
}
int qemu_read_config_file(const char *filename)
{
FILE *f = fopen(filename, "r");
int ret;
if (f == NULL) {
return -errno;
}
ret = qemu_config_parse(f, vm_config_groups, filename);
fclose(f);
if (ret == 0) {
return 0;
} else {
return -EINVAL;
}
}