qemu/qga/commands-posix.c
Alexander Ivanov a124109422 qga: Move HW address getting to a separate function
In the next patch FreeBSD support for guest-network-get-interfaces will be
added. Previously move Linux-specific code of HW address getting to a
separate functions and add a dumb function to commands-bsd.c.

Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>
2022-10-26 20:35:07 +03:00

3438 lines
96 KiB
C

/*
* QEMU Guest Agent POSIX-specific command implementations
*
* Copyright IBM Corp. 2011
*
* Authors:
* Michael Roth <mdroth@linux.vnet.ibm.com>
* Michal Privoznik <mprivozn@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <sys/wait.h>
#include <dirent.h>
#include "qga-qapi-commands.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "qemu/host-utils.h"
#include "qemu/sockets.h"
#include "qemu/base64.h"
#include "qemu/cutils.h"
#include "commands-common.h"
#include "block/nvme.h"
#include "cutils.h"
#ifdef HAVE_UTMPX
#include <utmpx.h>
#endif
#if defined(__linux__)
#include <mntent.h>
#include <sys/statvfs.h>
#include <linux/nvme_ioctl.h>
#ifdef CONFIG_LIBUDEV
#include <libudev.h>
#endif
#endif
#ifdef HAVE_GETIFADDRS
#include <arpa/inet.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/ethernet.h>
#include <sys/types.h>
#ifdef CONFIG_SOLARIS
#include <sys/sockio.h>
#endif
#endif
static void ga_wait_child(pid_t pid, int *status, Error **errp)
{
pid_t rpid;
*status = 0;
do {
rpid = waitpid(pid, status, 0);
} while (rpid == -1 && errno == EINTR);
if (rpid == -1) {
error_setg_errno(errp, errno, "failed to wait for child (pid: %d)",
pid);
return;
}
g_assert(rpid == pid);
}
void qmp_guest_shutdown(bool has_mode, const char *mode, Error **errp)
{
const char *shutdown_flag;
Error *local_err = NULL;
pid_t pid;
int status;
#ifdef CONFIG_SOLARIS
const char *powerdown_flag = "-i5";
const char *halt_flag = "-i0";
const char *reboot_flag = "-i6";
#elif defined(CONFIG_BSD)
const char *powerdown_flag = "-p";
const char *halt_flag = "-h";
const char *reboot_flag = "-r";
#else
const char *powerdown_flag = "-P";
const char *halt_flag = "-H";
const char *reboot_flag = "-r";
#endif
slog("guest-shutdown called, mode: %s", mode);
if (!has_mode || strcmp(mode, "powerdown") == 0) {
shutdown_flag = powerdown_flag;
} else if (strcmp(mode, "halt") == 0) {
shutdown_flag = halt_flag;
} else if (strcmp(mode, "reboot") == 0) {
shutdown_flag = reboot_flag;
} else {
error_setg(errp,
"mode is invalid (valid values are: halt|powerdown|reboot");
return;
}
pid = fork();
if (pid == 0) {
/* child, start the shutdown */
setsid();
reopen_fd_to_null(0);
reopen_fd_to_null(1);
reopen_fd_to_null(2);
#ifdef CONFIG_SOLARIS
execl("/sbin/shutdown", "shutdown", shutdown_flag, "-g0", "-y",
"hypervisor initiated shutdown", (char *)NULL);
#elif defined(CONFIG_BSD)
execl("/sbin/shutdown", "shutdown", shutdown_flag, "+0",
"hypervisor initiated shutdown", (char *)NULL);
#else
execl("/sbin/shutdown", "shutdown", "-h", shutdown_flag, "+0",
"hypervisor initiated shutdown", (char *)NULL);
#endif
_exit(EXIT_FAILURE);
} else if (pid < 0) {
error_setg_errno(errp, errno, "failed to create child process");
return;
}
ga_wait_child(pid, &status, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (!WIFEXITED(status)) {
error_setg(errp, "child process has terminated abnormally");
return;
}
if (WEXITSTATUS(status)) {
error_setg(errp, "child process has failed to shutdown");
return;
}
/* succeeded */
}
void qmp_guest_set_time(bool has_time, int64_t time_ns, Error **errp)
{
int ret;
int status;
pid_t pid;
Error *local_err = NULL;
struct timeval tv;
static const char hwclock_path[] = "/sbin/hwclock";
static int hwclock_available = -1;
if (hwclock_available < 0) {
hwclock_available = (access(hwclock_path, X_OK) == 0);
}
if (!hwclock_available) {
error_setg(errp, QERR_UNSUPPORTED);
return;
}
/* If user has passed a time, validate and set it. */
if (has_time) {
GDate date = { 0, };
/* year-2038 will overflow in case time_t is 32bit */
if (time_ns / 1000000000 != (time_t)(time_ns / 1000000000)) {
error_setg(errp, "Time %" PRId64 " is too large", time_ns);
return;
}
tv.tv_sec = time_ns / 1000000000;
tv.tv_usec = (time_ns % 1000000000) / 1000;
g_date_set_time_t(&date, tv.tv_sec);
if (date.year < 1970 || date.year >= 2070) {
error_setg_errno(errp, errno, "Invalid time");
return;
}
ret = settimeofday(&tv, NULL);
if (ret < 0) {
error_setg_errno(errp, errno, "Failed to set time to guest");
return;
}
}
/* Now, if user has passed a time to set and the system time is set, we
* just need to synchronize the hardware clock. However, if no time was
* passed, user is requesting the opposite: set the system time from the
* hardware clock (RTC). */
pid = fork();
if (pid == 0) {
setsid();
reopen_fd_to_null(0);
reopen_fd_to_null(1);
reopen_fd_to_null(2);
/* Use '/sbin/hwclock -w' to set RTC from the system time,
* or '/sbin/hwclock -s' to set the system time from RTC. */
execl(hwclock_path, "hwclock", has_time ? "-w" : "-s", NULL);
_exit(EXIT_FAILURE);
} else if (pid < 0) {
error_setg_errno(errp, errno, "failed to create child process");
return;
}
ga_wait_child(pid, &status, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (!WIFEXITED(status)) {
error_setg(errp, "child process has terminated abnormally");
return;
}
if (WEXITSTATUS(status)) {
error_setg(errp, "hwclock failed to set hardware clock to system time");
return;
}
}
typedef enum {
RW_STATE_NEW,
RW_STATE_READING,
RW_STATE_WRITING,
} RwState;
struct GuestFileHandle {
uint64_t id;
FILE *fh;
RwState state;
QTAILQ_ENTRY(GuestFileHandle) next;
};
static struct {
QTAILQ_HEAD(, GuestFileHandle) filehandles;
} guest_file_state = {
.filehandles = QTAILQ_HEAD_INITIALIZER(guest_file_state.filehandles),
};
static int64_t guest_file_handle_add(FILE *fh, Error **errp)
{
GuestFileHandle *gfh;
int64_t handle;
handle = ga_get_fd_handle(ga_state, errp);
if (handle < 0) {
return -1;
}
gfh = g_new0(GuestFileHandle, 1);
gfh->id = handle;
gfh->fh = fh;
QTAILQ_INSERT_TAIL(&guest_file_state.filehandles, gfh, next);
return handle;
}
GuestFileHandle *guest_file_handle_find(int64_t id, Error **errp)
{
GuestFileHandle *gfh;
QTAILQ_FOREACH(gfh, &guest_file_state.filehandles, next)
{
if (gfh->id == id) {
return gfh;
}
}
error_setg(errp, "handle '%" PRId64 "' has not been found", id);
return NULL;
}
typedef const char * const ccpc;
#ifndef O_BINARY
#define O_BINARY 0
#endif
/* http://pubs.opengroup.org/onlinepubs/9699919799/functions/fopen.html */
static const struct {
ccpc *forms;
int oflag_base;
} guest_file_open_modes[] = {
{ (ccpc[]){ "r", NULL }, O_RDONLY },
{ (ccpc[]){ "rb", NULL }, O_RDONLY | O_BINARY },
{ (ccpc[]){ "w", NULL }, O_WRONLY | O_CREAT | O_TRUNC },
{ (ccpc[]){ "wb", NULL }, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY },
{ (ccpc[]){ "a", NULL }, O_WRONLY | O_CREAT | O_APPEND },
{ (ccpc[]){ "ab", NULL }, O_WRONLY | O_CREAT | O_APPEND | O_BINARY },
{ (ccpc[]){ "r+", NULL }, O_RDWR },
{ (ccpc[]){ "rb+", "r+b", NULL }, O_RDWR | O_BINARY },
{ (ccpc[]){ "w+", NULL }, O_RDWR | O_CREAT | O_TRUNC },
{ (ccpc[]){ "wb+", "w+b", NULL }, O_RDWR | O_CREAT | O_TRUNC | O_BINARY },
{ (ccpc[]){ "a+", NULL }, O_RDWR | O_CREAT | O_APPEND },
{ (ccpc[]){ "ab+", "a+b", NULL }, O_RDWR | O_CREAT | O_APPEND | O_BINARY }
};
static int
find_open_flag(const char *mode_str, Error **errp)
{
unsigned mode;
for (mode = 0; mode < ARRAY_SIZE(guest_file_open_modes); ++mode) {
ccpc *form;
form = guest_file_open_modes[mode].forms;
while (*form != NULL && strcmp(*form, mode_str) != 0) {
++form;
}
if (*form != NULL) {
break;
}
}
if (mode == ARRAY_SIZE(guest_file_open_modes)) {
error_setg(errp, "invalid file open mode '%s'", mode_str);
return -1;
}
return guest_file_open_modes[mode].oflag_base | O_NOCTTY | O_NONBLOCK;
}
#define DEFAULT_NEW_FILE_MODE (S_IRUSR | S_IWUSR | \
S_IRGRP | S_IWGRP | \
S_IROTH | S_IWOTH)
static FILE *
safe_open_or_create(const char *path, const char *mode, Error **errp)
{
int oflag;
int fd = -1;
FILE *f = NULL;
oflag = find_open_flag(mode, errp);
if (oflag < 0) {
goto end;
}
/* If the caller wants / allows creation of a new file, we implement it
* with a two step process: open() + (open() / fchmod()).
*
* First we insist on creating the file exclusively as a new file. If
* that succeeds, we're free to set any file-mode bits on it. (The
* motivation is that we want to set those file-mode bits independently
* of the current umask.)
*
* If the exclusive creation fails because the file already exists
* (EEXIST is not possible for any other reason), we just attempt to
* open the file, but in this case we won't be allowed to change the
* file-mode bits on the preexistent file.
*
* The pathname should never disappear between the two open()s in
* practice. If it happens, then someone very likely tried to race us.
* In this case just go ahead and report the ENOENT from the second
* open() to the caller.
*
* If the caller wants to open a preexistent file, then the first
* open() is decisive and its third argument is ignored, and the second
* open() and the fchmod() are never called.
*/
fd = qga_open_cloexec(path, oflag | ((oflag & O_CREAT) ? O_EXCL : 0), 0);
if (fd == -1 && errno == EEXIST) {
oflag &= ~(unsigned)O_CREAT;
fd = qga_open_cloexec(path, oflag, 0);
}
if (fd == -1) {
error_setg_errno(errp, errno,
"failed to open file '%s' (mode: '%s')",
path, mode);
goto end;
}
if ((oflag & O_CREAT) && fchmod(fd, DEFAULT_NEW_FILE_MODE) == -1) {
error_setg_errno(errp, errno, "failed to set permission "
"0%03o on new file '%s' (mode: '%s')",
(unsigned)DEFAULT_NEW_FILE_MODE, path, mode);
goto end;
}
f = fdopen(fd, mode);
if (f == NULL) {
error_setg_errno(errp, errno, "failed to associate stdio stream with "
"file descriptor %d, file '%s' (mode: '%s')",
fd, path, mode);
}
end:
if (f == NULL && fd != -1) {
close(fd);
if (oflag & O_CREAT) {
unlink(path);
}
}
return f;
}
int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode,
Error **errp)
{
FILE *fh;
Error *local_err = NULL;
int64_t handle;
if (!has_mode) {
mode = "r";
}
slog("guest-file-open called, filepath: %s, mode: %s", path, mode);
fh = safe_open_or_create(path, mode, &local_err);
if (local_err != NULL) {
error_propagate(errp, local_err);
return -1;
}
/* set fd non-blocking to avoid common use cases (like reading from a
* named pipe) from hanging the agent
*/
if (!g_unix_set_fd_nonblocking(fileno(fh), true, NULL)) {
fclose(fh);
error_setg_errno(errp, errno, "Failed to set FD nonblocking");
return -1;
}
handle = guest_file_handle_add(fh, errp);
if (handle < 0) {
fclose(fh);
return -1;
}
slog("guest-file-open, handle: %" PRId64, handle);
return handle;
}
void qmp_guest_file_close(int64_t handle, Error **errp)
{
GuestFileHandle *gfh = guest_file_handle_find(handle, errp);
int ret;
slog("guest-file-close called, handle: %" PRId64, handle);
if (!gfh) {
return;
}
ret = fclose(gfh->fh);
if (ret == EOF) {
error_setg_errno(errp, errno, "failed to close handle");
return;
}
QTAILQ_REMOVE(&guest_file_state.filehandles, gfh, next);
g_free(gfh);
}
GuestFileRead *guest_file_read_unsafe(GuestFileHandle *gfh,
int64_t count, Error **errp)
{
GuestFileRead *read_data = NULL;
guchar *buf;
FILE *fh = gfh->fh;
size_t read_count;
/* explicitly flush when switching from writing to reading */
if (gfh->state == RW_STATE_WRITING) {
int ret = fflush(fh);
if (ret == EOF) {
error_setg_errno(errp, errno, "failed to flush file");
return NULL;
}
gfh->state = RW_STATE_NEW;
}
buf = g_malloc0(count + 1);
read_count = fread(buf, 1, count, fh);
if (ferror(fh)) {
error_setg_errno(errp, errno, "failed to read file");
} else {
buf[read_count] = 0;
read_data = g_new0(GuestFileRead, 1);
read_data->count = read_count;
read_data->eof = feof(fh);
if (read_count) {
read_data->buf_b64 = g_base64_encode(buf, read_count);
}
gfh->state = RW_STATE_READING;
}
g_free(buf);
clearerr(fh);
return read_data;
}
GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64,
bool has_count, int64_t count,
Error **errp)
{
GuestFileWrite *write_data = NULL;
guchar *buf;
gsize buf_len;
int write_count;
GuestFileHandle *gfh = guest_file_handle_find(handle, errp);
FILE *fh;
if (!gfh) {
return NULL;
}
fh = gfh->fh;
if (gfh->state == RW_STATE_READING) {
int ret = fseek(fh, 0, SEEK_CUR);
if (ret == -1) {
error_setg_errno(errp, errno, "failed to seek file");
return NULL;
}
gfh->state = RW_STATE_NEW;
}
buf = qbase64_decode(buf_b64, -1, &buf_len, errp);
if (!buf) {
return NULL;
}
if (!has_count) {
count = buf_len;
} else if (count < 0 || count > buf_len) {
error_setg(errp, "value '%" PRId64 "' is invalid for argument count",
count);
g_free(buf);
return NULL;
}
write_count = fwrite(buf, 1, count, fh);
if (ferror(fh)) {
error_setg_errno(errp, errno, "failed to write to file");
slog("guest-file-write failed, handle: %" PRId64, handle);
} else {
write_data = g_new0(GuestFileWrite, 1);
write_data->count = write_count;
write_data->eof = feof(fh);
gfh->state = RW_STATE_WRITING;
}
g_free(buf);
clearerr(fh);
return write_data;
}
struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset,
GuestFileWhence *whence_code,
Error **errp)
{
GuestFileHandle *gfh = guest_file_handle_find(handle, errp);
GuestFileSeek *seek_data = NULL;
FILE *fh;
int ret;
int whence;
Error *err = NULL;
if (!gfh) {
return NULL;
}
/* We stupidly exposed 'whence':'int' in our qapi */
whence = ga_parse_whence(whence_code, &err);
if (err) {
error_propagate(errp, err);
return NULL;
}
fh = gfh->fh;
ret = fseek(fh, offset, whence);
if (ret == -1) {
error_setg_errno(errp, errno, "failed to seek file");
if (errno == ESPIPE) {
/* file is non-seekable, stdio shouldn't be buffering anyways */
gfh->state = RW_STATE_NEW;
}
} else {
seek_data = g_new0(GuestFileSeek, 1);
seek_data->position = ftell(fh);
seek_data->eof = feof(fh);
gfh->state = RW_STATE_NEW;
}
clearerr(fh);
return seek_data;
}
void qmp_guest_file_flush(int64_t handle, Error **errp)
{
GuestFileHandle *gfh = guest_file_handle_find(handle, errp);
FILE *fh;
int ret;
if (!gfh) {
return;
}
fh = gfh->fh;
ret = fflush(fh);
if (ret == EOF) {
error_setg_errno(errp, errno, "failed to flush file");
} else {
gfh->state = RW_STATE_NEW;
}
}
#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
void free_fs_mount_list(FsMountList *mounts)
{
FsMount *mount, *temp;
if (!mounts) {
return;
}
QTAILQ_FOREACH_SAFE(mount, mounts, next, temp) {
QTAILQ_REMOVE(mounts, mount, next);
g_free(mount->dirname);
g_free(mount->devtype);
g_free(mount);
}
}
#endif
#if defined(CONFIG_FSFREEZE)
typedef enum {
FSFREEZE_HOOK_THAW = 0,
FSFREEZE_HOOK_FREEZE,
} FsfreezeHookArg;
static const char *fsfreeze_hook_arg_string[] = {
"thaw",
"freeze",
};
static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **errp)
{
int status;
pid_t pid;
const char *hook;
const char *arg_str = fsfreeze_hook_arg_string[arg];
Error *local_err = NULL;
hook = ga_fsfreeze_hook(ga_state);
if (!hook) {
return;
}
if (access(hook, X_OK) != 0) {
error_setg_errno(errp, errno, "can't access fsfreeze hook '%s'", hook);
return;
}
slog("executing fsfreeze hook with arg '%s'", arg_str);
pid = fork();
if (pid == 0) {
setsid();
reopen_fd_to_null(0);
reopen_fd_to_null(1);
reopen_fd_to_null(2);
execl(hook, hook, arg_str, NULL);
_exit(EXIT_FAILURE);
} else if (pid < 0) {
error_setg_errno(errp, errno, "failed to create child process");
return;
}
ga_wait_child(pid, &status, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (!WIFEXITED(status)) {
error_setg(errp, "fsfreeze hook has terminated abnormally");
return;
}
status = WEXITSTATUS(status);
if (status) {
error_setg(errp, "fsfreeze hook has failed with status %d", status);
return;
}
}
/*
* Return status of freeze/thaw
*/
GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error **errp)
{
if (ga_is_frozen(ga_state)) {
return GUEST_FSFREEZE_STATUS_FROZEN;
}
return GUEST_FSFREEZE_STATUS_THAWED;
}
int64_t qmp_guest_fsfreeze_freeze(Error **errp)
{
return qmp_guest_fsfreeze_freeze_list(false, NULL, errp);
}
int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
strList *mountpoints,
Error **errp)
{
int ret;
FsMountList mounts;
Error *local_err = NULL;
slog("guest-fsfreeze called");
execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return -1;
}
QTAILQ_INIT(&mounts);
if (!build_fs_mount_list(&mounts, &local_err)) {
error_propagate(errp, local_err);
return -1;
}
/* cannot risk guest agent blocking itself on a write in this state */
ga_set_frozen(ga_state);
ret = qmp_guest_fsfreeze_do_freeze_list(has_mountpoints, mountpoints,
mounts, errp);
free_fs_mount_list(&mounts);
/* We may not issue any FIFREEZE here.
* Just unset ga_state here and ready for the next call.
*/
if (ret == 0) {
ga_unset_frozen(ga_state);
} else if (ret < 0) {
qmp_guest_fsfreeze_thaw(NULL);
}
return ret;
}
int64_t qmp_guest_fsfreeze_thaw(Error **errp)
{
int ret;
ret = qmp_guest_fsfreeze_do_thaw(errp);
if (ret >= 0) {
ga_unset_frozen(ga_state);
execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
} else {
ret = 0;
}
return ret;
}
static void guest_fsfreeze_cleanup(void)
{
Error *err = NULL;
if (ga_is_frozen(ga_state) == GUEST_FSFREEZE_STATUS_FROZEN) {
qmp_guest_fsfreeze_thaw(&err);
if (err) {
slog("failed to clean up frozen filesystems: %s",
error_get_pretty(err));
error_free(err);
}
}
}
#endif
/* linux-specific implementations. avoid this if at all possible. */
#if defined(__linux__)
#if defined(CONFIG_FSFREEZE)
static char *get_pci_driver(char const *syspath, int pathlen, Error **errp)
{
char *path;
char *dpath;
char *driver = NULL;
char buf[PATH_MAX];
ssize_t len;
path = g_strndup(syspath, pathlen);
dpath = g_strdup_printf("%s/driver", path);
len = readlink(dpath, buf, sizeof(buf) - 1);
if (len != -1) {
buf[len] = 0;
driver = g_path_get_basename(buf);
}
g_free(dpath);
g_free(path);
return driver;
}
static int compare_uint(const void *_a, const void *_b)
{
unsigned int a = *(unsigned int *)_a;
unsigned int b = *(unsigned int *)_b;
return a < b ? -1 : a > b ? 1 : 0;
}
/* Walk the specified sysfs and build a sorted list of host or ata numbers */
static int build_hosts(char const *syspath, char const *host, bool ata,
unsigned int *hosts, int hosts_max, Error **errp)
{
char *path;
DIR *dir;
struct dirent *entry;
int i = 0;
path = g_strndup(syspath, host - syspath);
dir = opendir(path);
if (!dir) {
error_setg_errno(errp, errno, "opendir(\"%s\")", path);
g_free(path);
return -1;
}
while (i < hosts_max) {
entry = readdir(dir);
if (!entry) {
break;
}
if (ata && sscanf(entry->d_name, "ata%d", hosts + i) == 1) {
++i;
} else if (!ata && sscanf(entry->d_name, "host%d", hosts + i) == 1) {
++i;
}
}
qsort(hosts, i, sizeof(hosts[0]), compare_uint);
g_free(path);
closedir(dir);
return i;
}
/*
* Store disk device info for devices on the PCI bus.
* Returns true if information has been stored, or false for failure.
*/
static bool build_guest_fsinfo_for_pci_dev(char const *syspath,
GuestDiskAddress *disk,
Error **errp)
{
unsigned int pci[4], host, hosts[8], tgt[3];
int i, nhosts = 0, pcilen;
GuestPCIAddress *pciaddr = disk->pci_controller;
bool has_ata = false, has_host = false, has_tgt = false;
char *p, *q, *driver = NULL;
bool ret = false;
p = strstr(syspath, "/devices/pci");
if (!p || sscanf(p + 12, "%*x:%*x/%x:%x:%x.%x%n",
pci, pci + 1, pci + 2, pci + 3, &pcilen) < 4) {
g_debug("only pci device is supported: sysfs path '%s'", syspath);
return false;
}
p += 12 + pcilen;
while (true) {
driver = get_pci_driver(syspath, p - syspath, errp);
if (driver && (g_str_equal(driver, "ata_piix") ||
g_str_equal(driver, "sym53c8xx") ||
g_str_equal(driver, "virtio-pci") ||
g_str_equal(driver, "ahci") ||
g_str_equal(driver, "nvme"))) {
break;
}
g_free(driver);
if (sscanf(p, "/%x:%x:%x.%x%n",
pci, pci + 1, pci + 2, pci + 3, &pcilen) == 4) {
p += pcilen;
continue;
}
g_debug("unsupported driver or sysfs path '%s'", syspath);
return false;
}
p = strstr(syspath, "/target");
if (p && sscanf(p + 7, "%*u:%*u:%*u/%*u:%u:%u:%u",
tgt, tgt + 1, tgt + 2) == 3) {
has_tgt = true;
}
p = strstr(syspath, "/ata");
if (p) {
q = p + 4;
has_ata = true;
} else {
p = strstr(syspath, "/host");
q = p + 5;
}
if (p && sscanf(q, "%u", &host) == 1) {
has_host = true;
nhosts = build_hosts(syspath, p, has_ata, hosts,
ARRAY_SIZE(hosts), errp);
if (nhosts < 0) {
goto cleanup;
}
}
pciaddr->domain = pci[0];
pciaddr->bus = pci[1];
pciaddr->slot = pci[2];
pciaddr->function = pci[3];
if (strcmp(driver, "ata_piix") == 0) {
/* a host per ide bus, target*:0:<unit>:0 */
if (!has_host || !has_tgt) {
g_debug("invalid sysfs path '%s' (driver '%s')", syspath, driver);
goto cleanup;
}
for (i = 0; i < nhosts; i++) {
if (host == hosts[i]) {
disk->bus_type = GUEST_DISK_BUS_TYPE_IDE;
disk->bus = i;
disk->unit = tgt[1];
break;
}
}
if (i >= nhosts) {
g_debug("no host for '%s' (driver '%s')", syspath, driver);
goto cleanup;
}
} else if (strcmp(driver, "sym53c8xx") == 0) {
/* scsi(LSI Logic): target*:0:<unit>:0 */
if (!has_tgt) {
g_debug("invalid sysfs path '%s' (driver '%s')", syspath, driver);
goto cleanup;
}
disk->bus_type = GUEST_DISK_BUS_TYPE_SCSI;
disk->unit = tgt[1];
} else if (strcmp(driver, "virtio-pci") == 0) {
if (has_tgt) {
/* virtio-scsi: target*:0:0:<unit> */
disk->bus_type = GUEST_DISK_BUS_TYPE_SCSI;
disk->unit = tgt[2];
} else {
/* virtio-blk: 1 disk per 1 device */
disk->bus_type = GUEST_DISK_BUS_TYPE_VIRTIO;
}
} else if (strcmp(driver, "ahci") == 0) {
/* ahci: 1 host per 1 unit */
if (!has_host || !has_tgt) {
g_debug("invalid sysfs path '%s' (driver '%s')", syspath, driver);
goto cleanup;
}
for (i = 0; i < nhosts; i++) {
if (host == hosts[i]) {
disk->unit = i;
disk->bus_type = GUEST_DISK_BUS_TYPE_SATA;
break;
}
}
if (i >= nhosts) {
g_debug("no host for '%s' (driver '%s')", syspath, driver);
goto cleanup;
}
} else if (strcmp(driver, "nvme") == 0) {
disk->bus_type = GUEST_DISK_BUS_TYPE_NVME;
} else {
g_debug("unknown driver '%s' (sysfs path '%s')", driver, syspath);
goto cleanup;
}
ret = true;
cleanup:
g_free(driver);
return ret;
}
/*
* Store disk device info for non-PCI virtio devices (for example s390x
* channel I/O devices). Returns true if information has been stored, or
* false for failure.
*/
static bool build_guest_fsinfo_for_nonpci_virtio(char const *syspath,
GuestDiskAddress *disk,
Error **errp)
{
unsigned int tgt[3];
char *p;
if (!strstr(syspath, "/virtio") || !strstr(syspath, "/block")) {
g_debug("Unsupported virtio device '%s'", syspath);
return false;
}
p = strstr(syspath, "/target");
if (p && sscanf(p + 7, "%*u:%*u:%*u/%*u:%u:%u:%u",
&tgt[0], &tgt[1], &tgt[2]) == 3) {
/* virtio-scsi: target*:0:<target>:<unit> */
disk->bus_type = GUEST_DISK_BUS_TYPE_SCSI;
disk->bus = tgt[0];
disk->target = tgt[1];
disk->unit = tgt[2];
} else {
/* virtio-blk: 1 disk per 1 device */
disk->bus_type = GUEST_DISK_BUS_TYPE_VIRTIO;
}
return true;
}
/*
* Store disk device info for CCW devices (s390x channel I/O devices).
* Returns true if information has been stored, or false for failure.
*/
static bool build_guest_fsinfo_for_ccw_dev(char const *syspath,
GuestDiskAddress *disk,
Error **errp)
{
unsigned int cssid, ssid, subchno, devno;
char *p;
p = strstr(syspath, "/devices/css");
if (!p || sscanf(p + 12, "%*x/%x.%x.%x/%*x.%*x.%x/",
&cssid, &ssid, &subchno, &devno) < 4) {
g_debug("could not parse ccw device sysfs path: %s", syspath);
return false;
}
disk->has_ccw_address = true;
disk->ccw_address = g_new0(GuestCCWAddress, 1);
disk->ccw_address->cssid = cssid;
disk->ccw_address->ssid = ssid;
disk->ccw_address->subchno = subchno;
disk->ccw_address->devno = devno;
if (strstr(p, "/virtio")) {
build_guest_fsinfo_for_nonpci_virtio(syspath, disk, errp);
}
return true;
}
/* Store disk device info specified by @sysfs into @fs */
static void build_guest_fsinfo_for_real_device(char const *syspath,
GuestFilesystemInfo *fs,
Error **errp)
{
GuestDiskAddress *disk;
GuestPCIAddress *pciaddr;
bool has_hwinf;
#ifdef CONFIG_LIBUDEV
struct udev *udev = NULL;
struct udev_device *udevice = NULL;
#endif
pciaddr = g_new0(GuestPCIAddress, 1);
pciaddr->domain = -1; /* -1 means field is invalid */
pciaddr->bus = -1;
pciaddr->slot = -1;
pciaddr->function = -1;
disk = g_new0(GuestDiskAddress, 1);
disk->pci_controller = pciaddr;
disk->bus_type = GUEST_DISK_BUS_TYPE_UNKNOWN;
#ifdef CONFIG_LIBUDEV
udev = udev_new();
udevice = udev_device_new_from_syspath(udev, syspath);
if (udev == NULL || udevice == NULL) {
g_debug("failed to query udev");
} else {
const char *devnode, *serial;
devnode = udev_device_get_devnode(udevice);
if (devnode != NULL) {
disk->dev = g_strdup(devnode);
disk->has_dev = true;
}
serial = udev_device_get_property_value(udevice, "ID_SERIAL");
if (serial != NULL && *serial != 0) {
disk->serial = g_strdup(serial);
disk->has_serial = true;
}
}
udev_unref(udev);
udev_device_unref(udevice);
#endif
if (strstr(syspath, "/devices/pci")) {
has_hwinf = build_guest_fsinfo_for_pci_dev(syspath, disk, errp);
} else if (strstr(syspath, "/devices/css")) {
has_hwinf = build_guest_fsinfo_for_ccw_dev(syspath, disk, errp);
} else if (strstr(syspath, "/virtio")) {
has_hwinf = build_guest_fsinfo_for_nonpci_virtio(syspath, disk, errp);
} else {
g_debug("Unsupported device type for '%s'", syspath);
has_hwinf = false;
}
if (has_hwinf || disk->has_dev || disk->has_serial) {
QAPI_LIST_PREPEND(fs->disk, disk);
} else {
qapi_free_GuestDiskAddress(disk);
}
}
static void build_guest_fsinfo_for_device(char const *devpath,
GuestFilesystemInfo *fs,
Error **errp);
/* Store a list of slave devices of virtual volume specified by @syspath into
* @fs */
static void build_guest_fsinfo_for_virtual_device(char const *syspath,
GuestFilesystemInfo *fs,
Error **errp)
{
Error *err = NULL;
DIR *dir;
char *dirpath;
struct dirent *entry;
dirpath = g_strdup_printf("%s/slaves", syspath);
dir = opendir(dirpath);
if (!dir) {
if (errno != ENOENT) {
error_setg_errno(errp, errno, "opendir(\"%s\")", dirpath);
}
g_free(dirpath);
return;
}
for (;;) {
errno = 0;
entry = readdir(dir);
if (entry == NULL) {
if (errno) {
error_setg_errno(errp, errno, "readdir(\"%s\")", dirpath);
}
break;
}
if (entry->d_type == DT_LNK) {
char *path;
g_debug(" slave device '%s'", entry->d_name);
path = g_strdup_printf("%s/slaves/%s", syspath, entry->d_name);
build_guest_fsinfo_for_device(path, fs, &err);
g_free(path);
if (err) {
error_propagate(errp, err);
break;
}
}
}
g_free(dirpath);
closedir(dir);
}
static bool is_disk_virtual(const char *devpath, Error **errp)
{
g_autofree char *syspath = realpath(devpath, NULL);
if (!syspath) {
error_setg_errno(errp, errno, "realpath(\"%s\")", devpath);
return false;
}
return strstr(syspath, "/devices/virtual/block/") != NULL;
}
/* Dispatch to functions for virtual/real device */
static void build_guest_fsinfo_for_device(char const *devpath,
GuestFilesystemInfo *fs,
Error **errp)
{
ERRP_GUARD();
g_autofree char *syspath = NULL;
bool is_virtual = false;
syspath = realpath(devpath, NULL);
if (!syspath) {
if (errno != ENOENT) {
error_setg_errno(errp, errno, "realpath(\"%s\")", devpath);
return;
}
/* ENOENT: This devpath may not exist because of container config */
if (!fs->name) {
fs->name = g_path_get_basename(devpath);
}
return;
}
if (!fs->name) {
fs->name = g_path_get_basename(syspath);
}
g_debug(" parse sysfs path '%s'", syspath);
is_virtual = is_disk_virtual(syspath, errp);
if (*errp != NULL) {
return;
}
if (is_virtual) {
build_guest_fsinfo_for_virtual_device(syspath, fs, errp);
} else {
build_guest_fsinfo_for_real_device(syspath, fs, errp);
}
}
#ifdef CONFIG_LIBUDEV
/*
* Wrapper around build_guest_fsinfo_for_device() for getting just
* the disk address.
*/
static GuestDiskAddress *get_disk_address(const char *syspath, Error **errp)
{
g_autoptr(GuestFilesystemInfo) fs = NULL;
fs = g_new0(GuestFilesystemInfo, 1);
build_guest_fsinfo_for_device(syspath, fs, errp);
if (fs->disk != NULL) {
return g_steal_pointer(&fs->disk->value);
}
return NULL;
}
static char *get_alias_for_syspath(const char *syspath)
{
struct udev *udev = NULL;
struct udev_device *udevice = NULL;
char *ret = NULL;
udev = udev_new();
if (udev == NULL) {
g_debug("failed to query udev");
goto out;
}
udevice = udev_device_new_from_syspath(udev, syspath);
if (udevice == NULL) {
g_debug("failed to query udev for path: %s", syspath);
goto out;
} else {
const char *alias = udev_device_get_property_value(
udevice, "DM_NAME");
/*
* NULL means there was an error and empty string means there is no
* alias. In case of no alias we return NULL instead of empty string.
*/
if (alias == NULL) {
g_debug("failed to query udev for device alias for: %s",
syspath);
} else if (*alias != 0) {
ret = g_strdup(alias);
}
}
out:
udev_unref(udev);
udev_device_unref(udevice);
return ret;
}
static char *get_device_for_syspath(const char *syspath)
{
struct udev *udev = NULL;
struct udev_device *udevice = NULL;
char *ret = NULL;
udev = udev_new();
if (udev == NULL) {
g_debug("failed to query udev");
goto out;
}
udevice = udev_device_new_from_syspath(udev, syspath);
if (udevice == NULL) {
g_debug("failed to query udev for path: %s", syspath);
goto out;
} else {
ret = g_strdup(udev_device_get_devnode(udevice));
}
out:
udev_unref(udev);
udev_device_unref(udevice);
return ret;
}
static void get_disk_deps(const char *disk_dir, GuestDiskInfo *disk)
{
g_autofree char *deps_dir = NULL;
const gchar *dep;
GDir *dp_deps = NULL;
/* List dependent disks */
deps_dir = g_strdup_printf("%s/slaves", disk_dir);
g_debug(" listing entries in: %s", deps_dir);
dp_deps = g_dir_open(deps_dir, 0, NULL);
if (dp_deps == NULL) {
g_debug("failed to list entries in %s", deps_dir);
return;
}
disk->has_dependencies = true;
while ((dep = g_dir_read_name(dp_deps)) != NULL) {
g_autofree char *dep_dir = NULL;
char *dev_name;
/* Add dependent disks */
dep_dir = g_strdup_printf("%s/%s", deps_dir, dep);
dev_name = get_device_for_syspath(dep_dir);
if (dev_name != NULL) {
g_debug(" adding dependent device: %s", dev_name);
QAPI_LIST_PREPEND(disk->dependencies, dev_name);
}
}
g_dir_close(dp_deps);
}
/*
* Detect partitions subdirectory, name is "<disk_name><number>" or
* "<disk_name>p<number>"
*
* @disk_name -- last component of /sys path (e.g. sda)
* @disk_dir -- sys path of the disk (e.g. /sys/block/sda)
* @disk_dev -- device node of the disk (e.g. /dev/sda)
*/
static GuestDiskInfoList *get_disk_partitions(
GuestDiskInfoList *list,
const char *disk_name, const char *disk_dir,
const char *disk_dev)
{
GuestDiskInfoList *ret = list;
struct dirent *de_disk;
DIR *dp_disk = NULL;
size_t len = strlen(disk_name);
dp_disk = opendir(disk_dir);
while ((de_disk = readdir(dp_disk)) != NULL) {
g_autofree char *partition_dir = NULL;
char *dev_name;
GuestDiskInfo *partition;
if (!(de_disk->d_type & DT_DIR)) {
continue;
}
if (!(strncmp(disk_name, de_disk->d_name, len) == 0 &&
((*(de_disk->d_name + len) == 'p' &&
isdigit(*(de_disk->d_name + len + 1))) ||
isdigit(*(de_disk->d_name + len))))) {
continue;
}
partition_dir = g_strdup_printf("%s/%s",
disk_dir, de_disk->d_name);
dev_name = get_device_for_syspath(partition_dir);
if (dev_name == NULL) {
g_debug("Failed to get device name for syspath: %s",
disk_dir);
continue;
}
partition = g_new0(GuestDiskInfo, 1);
partition->name = dev_name;
partition->partition = true;
partition->has_dependencies = true;
/* Add parent disk as dependent for easier tracking of hierarchy */
QAPI_LIST_PREPEND(partition->dependencies, g_strdup(disk_dev));
QAPI_LIST_PREPEND(ret, partition);
}
closedir(dp_disk);
return ret;
}
static void get_nvme_smart(GuestDiskInfo *disk)
{
int fd;
GuestNVMeSmart *smart;
NvmeSmartLog log = {0};
struct nvme_admin_cmd cmd = {
.opcode = NVME_ADM_CMD_GET_LOG_PAGE,
.nsid = NVME_NSID_BROADCAST,
.addr = (uintptr_t)&log,
.data_len = sizeof(log),
.cdw10 = NVME_LOG_SMART_INFO | (1 << 15) /* RAE bit */
| (((sizeof(log) >> 2) - 1) << 16)
};
fd = qga_open_cloexec(disk->name, O_RDONLY, 0);
if (fd == -1) {
g_debug("Failed to open device: %s: %s", disk->name, g_strerror(errno));
return;
}
if (ioctl(fd, NVME_IOCTL_ADMIN_CMD, &cmd)) {
g_debug("Failed to get smart: %s: %s", disk->name, g_strerror(errno));
close(fd);
return;
}
disk->has_smart = true;
disk->smart = g_new0(GuestDiskSmart, 1);
disk->smart->type = GUEST_DISK_BUS_TYPE_NVME;
smart = &disk->smart->u.nvme;
smart->critical_warning = log.critical_warning;
smart->temperature = lduw_le_p(&log.temperature); /* unaligned field */
smart->available_spare = log.available_spare;
smart->available_spare_threshold = log.available_spare_threshold;
smart->percentage_used = log.percentage_used;
smart->data_units_read_lo = le64_to_cpu(log.data_units_read[0]);
smart->data_units_read_hi = le64_to_cpu(log.data_units_read[1]);
smart->data_units_written_lo = le64_to_cpu(log.data_units_written[0]);
smart->data_units_written_hi = le64_to_cpu(log.data_units_written[1]);
smart->host_read_commands_lo = le64_to_cpu(log.host_read_commands[0]);
smart->host_read_commands_hi = le64_to_cpu(log.host_read_commands[1]);
smart->host_write_commands_lo = le64_to_cpu(log.host_write_commands[0]);
smart->host_write_commands_hi = le64_to_cpu(log.host_write_commands[1]);
smart->controller_busy_time_lo = le64_to_cpu(log.controller_busy_time[0]);
smart->controller_busy_time_hi = le64_to_cpu(log.controller_busy_time[1]);
smart->power_cycles_lo = le64_to_cpu(log.power_cycles[0]);
smart->power_cycles_hi = le64_to_cpu(log.power_cycles[1]);
smart->power_on_hours_lo = le64_to_cpu(log.power_on_hours[0]);
smart->power_on_hours_hi = le64_to_cpu(log.power_on_hours[1]);
smart->unsafe_shutdowns_lo = le64_to_cpu(log.unsafe_shutdowns[0]);
smart->unsafe_shutdowns_hi = le64_to_cpu(log.unsafe_shutdowns[1]);
smart->media_errors_lo = le64_to_cpu(log.media_errors[0]);
smart->media_errors_hi = le64_to_cpu(log.media_errors[1]);
smart->number_of_error_log_entries_lo =
le64_to_cpu(log.number_of_error_log_entries[0]);
smart->number_of_error_log_entries_hi =
le64_to_cpu(log.number_of_error_log_entries[1]);
close(fd);
}
static void get_disk_smart(GuestDiskInfo *disk)
{
if (disk->has_address
&& (disk->address->bus_type == GUEST_DISK_BUS_TYPE_NVME)) {
get_nvme_smart(disk);
}
}
GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
{
GuestDiskInfoList *ret = NULL;
GuestDiskInfo *disk;
DIR *dp = NULL;
struct dirent *de = NULL;
g_debug("listing /sys/block directory");
dp = opendir("/sys/block");
if (dp == NULL) {
error_setg_errno(errp, errno, "Can't open directory \"/sys/block\"");
return NULL;
}
while ((de = readdir(dp)) != NULL) {
g_autofree char *disk_dir = NULL, *line = NULL,
*size_path = NULL;
char *dev_name;
Error *local_err = NULL;
if (de->d_type != DT_LNK) {
g_debug(" skipping entry: %s", de->d_name);
continue;
}
/* Check size and skip zero-sized disks */
g_debug(" checking disk size");
size_path = g_strdup_printf("/sys/block/%s/size", de->d_name);
if (!g_file_get_contents(size_path, &line, NULL, NULL)) {
g_debug(" failed to read disk size");
continue;
}
if (g_strcmp0(line, "0\n") == 0) {
g_debug(" skipping zero-sized disk");
continue;
}
g_debug(" adding %s", de->d_name);
disk_dir = g_strdup_printf("/sys/block/%s", de->d_name);
dev_name = get_device_for_syspath(disk_dir);
if (dev_name == NULL) {
g_debug("Failed to get device name for syspath: %s",
disk_dir);
continue;
}
disk = g_new0(GuestDiskInfo, 1);
disk->name = dev_name;
disk->partition = false;
disk->alias = get_alias_for_syspath(disk_dir);
disk->has_alias = (disk->alias != NULL);
QAPI_LIST_PREPEND(ret, disk);
/* Get address for non-virtual devices */
bool is_virtual = is_disk_virtual(disk_dir, &local_err);
if (local_err != NULL) {
g_debug(" failed to check disk path, ignoring error: %s",
error_get_pretty(local_err));
error_free(local_err);
local_err = NULL;
/* Don't try to get the address */
is_virtual = true;
}
if (!is_virtual) {
disk->address = get_disk_address(disk_dir, &local_err);
if (local_err != NULL) {
g_debug(" failed to get device info, ignoring error: %s",
error_get_pretty(local_err));
error_free(local_err);
local_err = NULL;
} else if (disk->address != NULL) {
disk->has_address = true;
}
}
get_disk_deps(disk_dir, disk);
get_disk_smart(disk);
ret = get_disk_partitions(ret, de->d_name, disk_dir, dev_name);
}
closedir(dp);
return ret;
}
#else
GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif
/* Return a list of the disk device(s)' info which @mount lies on */
static GuestFilesystemInfo *build_guest_fsinfo(struct FsMount *mount,
Error **errp)
{
GuestFilesystemInfo *fs = g_malloc0(sizeof(*fs));
struct statvfs buf;
unsigned long used, nonroot_total, fr_size;
char *devpath = g_strdup_printf("/sys/dev/block/%u:%u",
mount->devmajor, mount->devminor);
fs->mountpoint = g_strdup(mount->dirname);
fs->type = g_strdup(mount->devtype);
build_guest_fsinfo_for_device(devpath, fs, errp);
if (statvfs(fs->mountpoint, &buf) == 0) {
fr_size = buf.f_frsize;
used = buf.f_blocks - buf.f_bfree;
nonroot_total = used + buf.f_bavail;
fs->used_bytes = used * fr_size;
fs->total_bytes = nonroot_total * fr_size;
fs->has_total_bytes = true;
fs->has_used_bytes = true;
}
g_free(devpath);
return fs;
}
GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
{
FsMountList mounts;
struct FsMount *mount;
GuestFilesystemInfoList *ret = NULL;
Error *local_err = NULL;
QTAILQ_INIT(&mounts);
if (!build_fs_mount_list(&mounts, &local_err)) {
error_propagate(errp, local_err);
return NULL;
}
QTAILQ_FOREACH(mount, &mounts, next) {
g_debug("Building guest fsinfo for '%s'", mount->dirname);
QAPI_LIST_PREPEND(ret, build_guest_fsinfo(mount, &local_err));
if (local_err) {
error_propagate(errp, local_err);
qapi_free_GuestFilesystemInfoList(ret);
ret = NULL;
break;
}
}
free_fs_mount_list(&mounts);
return ret;
}
#endif /* CONFIG_FSFREEZE */
#if defined(CONFIG_FSTRIM)
/*
* Walk list of mounted file systems in the guest, and trim them.
*/
GuestFilesystemTrimResponse *
qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
{
GuestFilesystemTrimResponse *response;
GuestFilesystemTrimResult *result;
int ret = 0;
FsMountList mounts;
struct FsMount *mount;
int fd;
struct fstrim_range r;
slog("guest-fstrim called");
QTAILQ_INIT(&mounts);
if (!build_fs_mount_list(&mounts, errp)) {
return NULL;
}
response = g_malloc0(sizeof(*response));
QTAILQ_FOREACH(mount, &mounts, next) {
result = g_malloc0(sizeof(*result));
result->path = g_strdup(mount->dirname);
QAPI_LIST_PREPEND(response->paths, result);
fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
if (fd == -1) {
result->error = g_strdup_printf("failed to open: %s",
strerror(errno));
result->has_error = true;
continue;
}
/* We try to cull filesystems we know won't work in advance, but other
* filesystems may not implement fstrim for less obvious reasons.
* These will report EOPNOTSUPP; while in some other cases ENOTTY
* will be reported (e.g. CD-ROMs).
* Any other error means an unexpected error.
*/
r.start = 0;
r.len = -1;
r.minlen = has_minimum ? minimum : 0;
ret = ioctl(fd, FITRIM, &r);
if (ret == -1) {
result->has_error = true;
if (errno == ENOTTY || errno == EOPNOTSUPP) {
result->error = g_strdup("trim not supported");
} else {
result->error = g_strdup_printf("failed to trim: %s",
strerror(errno));
}
close(fd);
continue;
}
result->has_minimum = true;
result->minimum = r.minlen;
result->has_trimmed = true;
result->trimmed = r.len;
close(fd);
}
free_fs_mount_list(&mounts);
return response;
}
#endif /* CONFIG_FSTRIM */
#define LINUX_SYS_STATE_FILE "/sys/power/state"
#define SUSPEND_SUPPORTED 0
#define SUSPEND_NOT_SUPPORTED 1
typedef enum {
SUSPEND_MODE_DISK = 0,
SUSPEND_MODE_RAM = 1,
SUSPEND_MODE_HYBRID = 2,
} SuspendMode;
/*
* Executes a command in a child process using g_spawn_sync,
* returning an int >= 0 representing the exit status of the
* process.
*
* If the program wasn't found in path, returns -1.
*
* If a problem happened when creating the child process,
* returns -1 and errp is set.
*/
static int run_process_child(const char *command[], Error **errp)
{
int exit_status, spawn_flag;
GError *g_err = NULL;
bool success;
spawn_flag = G_SPAWN_SEARCH_PATH | G_SPAWN_STDOUT_TO_DEV_NULL |
G_SPAWN_STDERR_TO_DEV_NULL;
success = g_spawn_sync(NULL, (char **)command, NULL, spawn_flag,
NULL, NULL, NULL, NULL,
&exit_status, &g_err);
if (success) {
return WEXITSTATUS(exit_status);
}
if (g_err && (g_err->code != G_SPAWN_ERROR_NOENT)) {
error_setg(errp, "failed to create child process, error '%s'",
g_err->message);
}
g_error_free(g_err);
return -1;
}
static bool systemd_supports_mode(SuspendMode mode, Error **errp)
{
const char *systemctl_args[3] = {"systemd-hibernate", "systemd-suspend",
"systemd-hybrid-sleep"};
const char *cmd[4] = {"systemctl", "status", systemctl_args[mode], NULL};
int status;
status = run_process_child(cmd, errp);
/*
* systemctl status uses LSB return codes so we can expect
* status > 0 and be ok. To assert if the guest has support
* for the selected suspend mode, status should be < 4. 4 is
* the code for unknown service status, the return value when
* the service does not exist. A common value is status = 3
* (program is not running).
*/
if (status > 0 && status < 4) {
return true;
}
return false;
}
static void systemd_suspend(SuspendMode mode, Error **errp)
{
Error *local_err = NULL;
const char *systemctl_args[3] = {"hibernate", "suspend", "hybrid-sleep"};
const char *cmd[3] = {"systemctl", systemctl_args[mode], NULL};
int status;
status = run_process_child(cmd, &local_err);
if (status == 0) {
return;
}
if ((status == -1) && !local_err) {
error_setg(errp, "the helper program 'systemctl %s' was not found",
systemctl_args[mode]);
return;
}
if (local_err) {
error_propagate(errp, local_err);
} else {
error_setg(errp, "the helper program 'systemctl %s' returned an "
"unexpected exit status code (%d)",
systemctl_args[mode], status);
}
}
static bool pmutils_supports_mode(SuspendMode mode, Error **errp)
{
Error *local_err = NULL;
const char *pmutils_args[3] = {"--hibernate", "--suspend",
"--suspend-hybrid"};
const char *cmd[3] = {"pm-is-supported", pmutils_args[mode], NULL};
int status;
status = run_process_child(cmd, &local_err);
if (status == SUSPEND_SUPPORTED) {
return true;
}
if ((status == -1) && !local_err) {
return false;
}
if (local_err) {
error_propagate(errp, local_err);
} else {
error_setg(errp,
"the helper program '%s' returned an unexpected exit"
" status code (%d)", "pm-is-supported", status);
}
return false;
}
static void pmutils_suspend(SuspendMode mode, Error **errp)
{
Error *local_err = NULL;
const char *pmutils_binaries[3] = {"pm-hibernate", "pm-suspend",
"pm-suspend-hybrid"};
const char *cmd[2] = {pmutils_binaries[mode], NULL};
int status;
status = run_process_child(cmd, &local_err);
if (status == 0) {
return;
}
if ((status == -1) && !local_err) {
error_setg(errp, "the helper program '%s' was not found",
pmutils_binaries[mode]);
return;
}
if (local_err) {
error_propagate(errp, local_err);
} else {
error_setg(errp,
"the helper program '%s' returned an unexpected exit"
" status code (%d)", pmutils_binaries[mode], status);
}
}
static bool linux_sys_state_supports_mode(SuspendMode mode, Error **errp)
{
const char *sysfile_strs[3] = {"disk", "mem", NULL};
const char *sysfile_str = sysfile_strs[mode];
char buf[32]; /* hopefully big enough */
int fd;
ssize_t ret;
if (!sysfile_str) {
error_setg(errp, "unknown guest suspend mode");
return false;
}
fd = open(LINUX_SYS_STATE_FILE, O_RDONLY);
if (fd < 0) {
return false;
}
ret = read(fd, buf, sizeof(buf) - 1);
close(fd);
if (ret <= 0) {
return false;
}
buf[ret] = '\0';
if (strstr(buf, sysfile_str)) {
return true;
}
return false;
}
static void linux_sys_state_suspend(SuspendMode mode, Error **errp)
{
Error *local_err = NULL;
const char *sysfile_strs[3] = {"disk", "mem", NULL};
const char *sysfile_str = sysfile_strs[mode];
pid_t pid;
int status;
if (!sysfile_str) {
error_setg(errp, "unknown guest suspend mode");
return;
}
pid = fork();
if (!pid) {
/* child */
int fd;
setsid();
reopen_fd_to_null(0);
reopen_fd_to_null(1);
reopen_fd_to_null(2);
fd = open(LINUX_SYS_STATE_FILE, O_WRONLY);
if (fd < 0) {
_exit(EXIT_FAILURE);
}
if (write(fd, sysfile_str, strlen(sysfile_str)) < 0) {
_exit(EXIT_FAILURE);
}
_exit(EXIT_SUCCESS);
} else if (pid < 0) {
error_setg_errno(errp, errno, "failed to create child process");
return;
}
ga_wait_child(pid, &status, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
if (WEXITSTATUS(status)) {
error_setg(errp, "child process has failed to suspend");
}
}
static void guest_suspend(SuspendMode mode, Error **errp)
{
Error *local_err = NULL;
bool mode_supported = false;
if (systemd_supports_mode(mode, &local_err)) {
mode_supported = true;
systemd_suspend(mode, &local_err);
}
if (!local_err) {
return;
}
error_free(local_err);
local_err = NULL;
if (pmutils_supports_mode(mode, &local_err)) {
mode_supported = true;
pmutils_suspend(mode, &local_err);
}
if (!local_err) {
return;
}
error_free(local_err);
local_err = NULL;
if (linux_sys_state_supports_mode(mode, &local_err)) {
mode_supported = true;
linux_sys_state_suspend(mode, &local_err);
}
if (!mode_supported) {
error_free(local_err);
error_setg(errp,
"the requested suspend mode is not supported by the guest");
} else {
error_propagate(errp, local_err);
}
}
void qmp_guest_suspend_disk(Error **errp)
{
guest_suspend(SUSPEND_MODE_DISK, errp);
}
void qmp_guest_suspend_ram(Error **errp)
{
guest_suspend(SUSPEND_MODE_RAM, errp);
}
void qmp_guest_suspend_hybrid(Error **errp)
{
guest_suspend(SUSPEND_MODE_HYBRID, errp);
}
/* Transfer online/offline status between @vcpu and the guest system.
*
* On input either @errp or *@errp must be NULL.
*
* In system-to-@vcpu direction, the following @vcpu fields are accessed:
* - R: vcpu->logical_id
* - W: vcpu->online
* - W: vcpu->can_offline
*
* In @vcpu-to-system direction, the following @vcpu fields are accessed:
* - R: vcpu->logical_id
* - R: vcpu->online
*
* Written members remain unmodified on error.
*/
static void transfer_vcpu(GuestLogicalProcessor *vcpu, bool sys2vcpu,
char *dirpath, Error **errp)
{
int fd;
int res;
int dirfd;
static const char fn[] = "online";
dirfd = open(dirpath, O_RDONLY | O_DIRECTORY);
if (dirfd == -1) {
error_setg_errno(errp, errno, "open(\"%s\")", dirpath);
return;
}
fd = openat(dirfd, fn, sys2vcpu ? O_RDONLY : O_RDWR);
if (fd == -1) {
if (errno != ENOENT) {
error_setg_errno(errp, errno, "open(\"%s/%s\")", dirpath, fn);
} else if (sys2vcpu) {
vcpu->online = true;
vcpu->can_offline = false;
} else if (!vcpu->online) {
error_setg(errp, "logical processor #%" PRId64 " can't be "
"offlined", vcpu->logical_id);
} /* otherwise pretend successful re-onlining */
} else {
unsigned char status;
res = pread(fd, &status, 1, 0);
if (res == -1) {
error_setg_errno(errp, errno, "pread(\"%s/%s\")", dirpath, fn);
} else if (res == 0) {
error_setg(errp, "pread(\"%s/%s\"): unexpected EOF", dirpath,
fn);
} else if (sys2vcpu) {
vcpu->online = (status != '0');
vcpu->can_offline = true;
} else if (vcpu->online != (status != '0')) {
status = '0' + vcpu->online;
if (pwrite(fd, &status, 1, 0) == -1) {
error_setg_errno(errp, errno, "pwrite(\"%s/%s\")", dirpath,
fn);
}
} /* otherwise pretend successful re-(on|off)-lining */
res = close(fd);
g_assert(res == 0);
}
res = close(dirfd);
g_assert(res == 0);
}
GuestLogicalProcessorList *qmp_guest_get_vcpus(Error **errp)
{
GuestLogicalProcessorList *head, **tail;
const char *cpu_dir = "/sys/devices/system/cpu";
const gchar *line;
g_autoptr(GDir) cpu_gdir = NULL;
Error *local_err = NULL;
head = NULL;
tail = &head;
cpu_gdir = g_dir_open(cpu_dir, 0, NULL);
if (cpu_gdir == NULL) {
error_setg_errno(errp, errno, "failed to list entries: %s", cpu_dir);
return NULL;
}
while (local_err == NULL && (line = g_dir_read_name(cpu_gdir)) != NULL) {
GuestLogicalProcessor *vcpu;
int64_t id;
if (sscanf(line, "cpu%" PRId64, &id)) {
g_autofree char *path = g_strdup_printf("/sys/devices/system/cpu/"
"cpu%" PRId64 "/", id);
vcpu = g_malloc0(sizeof *vcpu);
vcpu->logical_id = id;
vcpu->has_can_offline = true; /* lolspeak ftw */
transfer_vcpu(vcpu, true, path, &local_err);
QAPI_LIST_APPEND(tail, vcpu);
}
}
if (local_err == NULL) {
/* there's no guest with zero VCPUs */
g_assert(head != NULL);
return head;
}
qapi_free_GuestLogicalProcessorList(head);
error_propagate(errp, local_err);
return NULL;
}
int64_t qmp_guest_set_vcpus(GuestLogicalProcessorList *vcpus, Error **errp)
{
int64_t processed;
Error *local_err = NULL;
processed = 0;
while (vcpus != NULL) {
char *path = g_strdup_printf("/sys/devices/system/cpu/cpu%" PRId64 "/",
vcpus->value->logical_id);
transfer_vcpu(vcpus->value, false, path, &local_err);
g_free(path);
if (local_err != NULL) {
break;
}
++processed;
vcpus = vcpus->next;
}
if (local_err != NULL) {
if (processed == 0) {
error_propagate(errp, local_err);
} else {
error_free(local_err);
}
}
return processed;
}
#endif /* __linux__ */
#if defined(__linux__) || defined(__FreeBSD__)
void qmp_guest_set_user_password(const char *username,
const char *password,
bool crypted,
Error **errp)
{
Error *local_err = NULL;
char *passwd_path = NULL;
pid_t pid;
int status;
int datafd[2] = { -1, -1 };
char *rawpasswddata = NULL;
size_t rawpasswdlen;
char *chpasswddata = NULL;
size_t chpasswdlen;
rawpasswddata = (char *)qbase64_decode(password, -1, &rawpasswdlen, errp);
if (!rawpasswddata) {
return;
}
rawpasswddata = g_renew(char, rawpasswddata, rawpasswdlen + 1);
rawpasswddata[rawpasswdlen] = '\0';
if (strchr(rawpasswddata, '\n')) {
error_setg(errp, "forbidden characters in raw password");
goto out;
}
if (strchr(username, '\n') ||
strchr(username, ':')) {
error_setg(errp, "forbidden characters in username");
goto out;
}
#ifdef __FreeBSD__
chpasswddata = g_strdup(rawpasswddata);
passwd_path = g_find_program_in_path("pw");
#else
chpasswddata = g_strdup_printf("%s:%s\n", username, rawpasswddata);
passwd_path = g_find_program_in_path("chpasswd");
#endif
chpasswdlen = strlen(chpasswddata);
if (!passwd_path) {
error_setg(errp, "cannot find 'passwd' program in PATH");
goto out;
}
if (!g_unix_open_pipe(datafd, FD_CLOEXEC, NULL)) {
error_setg(errp, "cannot create pipe FDs");
goto out;
}
pid = fork();
if (pid == 0) {
close(datafd[1]);
/* child */
setsid();
dup2(datafd[0], 0);
reopen_fd_to_null(1);
reopen_fd_to_null(2);
#ifdef __FreeBSD__
const char *h_arg;
h_arg = (crypted) ? "-H" : "-h";
execl(passwd_path, "pw", "usermod", "-n", username, h_arg, "0", NULL);
#else
if (crypted) {
execl(passwd_path, "chpasswd", "-e", NULL);
} else {
execl(passwd_path, "chpasswd", NULL);
}
#endif
_exit(EXIT_FAILURE);
} else if (pid < 0) {
error_setg_errno(errp, errno, "failed to create child process");
goto out;
}
close(datafd[0]);
datafd[0] = -1;
if (qemu_write_full(datafd[1], chpasswddata, chpasswdlen) != chpasswdlen) {
error_setg_errno(errp, errno, "cannot write new account password");
goto out;
}
close(datafd[1]);
datafd[1] = -1;
ga_wait_child(pid, &status, &local_err);
if (local_err) {
error_propagate(errp, local_err);
goto out;
}
if (!WIFEXITED(status)) {
error_setg(errp, "child process has terminated abnormally");
goto out;
}
if (WEXITSTATUS(status)) {
error_setg(errp, "child process has failed to set user password");
goto out;
}
out:
g_free(chpasswddata);
g_free(rawpasswddata);
g_free(passwd_path);
if (datafd[0] != -1) {
close(datafd[0]);
}
if (datafd[1] != -1) {
close(datafd[1]);
}
}
#else /* __linux__ || __FreeBSD__ */
void qmp_guest_set_user_password(const char *username,
const char *password,
bool crypted,
Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
}
#endif /* __linux__ || __FreeBSD__ */
#ifdef __linux__
static void ga_read_sysfs_file(int dirfd, const char *pathname, char *buf,
int size, Error **errp)
{
int fd;
int res;
errno = 0;
fd = openat(dirfd, pathname, O_RDONLY);
if (fd == -1) {
error_setg_errno(errp, errno, "open sysfs file \"%s\"", pathname);
return;
}
res = pread(fd, buf, size, 0);
if (res == -1) {
error_setg_errno(errp, errno, "pread sysfs file \"%s\"", pathname);
} else if (res == 0) {
error_setg(errp, "pread sysfs file \"%s\": unexpected EOF", pathname);
}
close(fd);
}
static void ga_write_sysfs_file(int dirfd, const char *pathname,
const char *buf, int size, Error **errp)
{
int fd;
errno = 0;
fd = openat(dirfd, pathname, O_WRONLY);
if (fd == -1) {
error_setg_errno(errp, errno, "open sysfs file \"%s\"", pathname);
return;
}
if (pwrite(fd, buf, size, 0) == -1) {
error_setg_errno(errp, errno, "pwrite sysfs file \"%s\"", pathname);
}
close(fd);
}
/* Transfer online/offline status between @mem_blk and the guest system.
*
* On input either @errp or *@errp must be NULL.
*
* In system-to-@mem_blk direction, the following @mem_blk fields are accessed:
* - R: mem_blk->phys_index
* - W: mem_blk->online
* - W: mem_blk->can_offline
*
* In @mem_blk-to-system direction, the following @mem_blk fields are accessed:
* - R: mem_blk->phys_index
* - R: mem_blk->online
*- R: mem_blk->can_offline
* Written members remain unmodified on error.
*/
static void transfer_memory_block(GuestMemoryBlock *mem_blk, bool sys2memblk,
GuestMemoryBlockResponse *result,
Error **errp)
{
char *dirpath;
int dirfd;
char *status;
Error *local_err = NULL;
if (!sys2memblk) {
DIR *dp;
if (!result) {
error_setg(errp, "Internal error, 'result' should not be NULL");
return;
}
errno = 0;
dp = opendir("/sys/devices/system/memory/");
/* if there is no 'memory' directory in sysfs,
* we think this VM does not support online/offline memory block,
* any other solution?
*/
if (!dp) {
if (errno == ENOENT) {
result->response =
GUEST_MEMORY_BLOCK_RESPONSE_TYPE_OPERATION_NOT_SUPPORTED;
}
goto out1;
}
closedir(dp);
}
dirpath = g_strdup_printf("/sys/devices/system/memory/memory%" PRId64 "/",
mem_blk->phys_index);
dirfd = open(dirpath, O_RDONLY | O_DIRECTORY);
if (dirfd == -1) {
if (sys2memblk) {
error_setg_errno(errp, errno, "open(\"%s\")", dirpath);
} else {
if (errno == ENOENT) {
result->response = GUEST_MEMORY_BLOCK_RESPONSE_TYPE_NOT_FOUND;
} else {
result->response =
GUEST_MEMORY_BLOCK_RESPONSE_TYPE_OPERATION_FAILED;
}
}
g_free(dirpath);
goto out1;
}
g_free(dirpath);
status = g_malloc0(10);
ga_read_sysfs_file(dirfd, "state", status, 10, &local_err);
if (local_err) {
/* treat with sysfs file that not exist in old kernel */
if (errno == ENOENT) {
error_free(local_err);
if (sys2memblk) {
mem_blk->online = true;
mem_blk->can_offline = false;
} else if (!mem_blk->online) {
result->response =
GUEST_MEMORY_BLOCK_RESPONSE_TYPE_OPERATION_NOT_SUPPORTED;
}
} else {
if (sys2memblk) {
error_propagate(errp, local_err);
} else {
error_free(local_err);
result->response =
GUEST_MEMORY_BLOCK_RESPONSE_TYPE_OPERATION_FAILED;
}
}
goto out2;
}
if (sys2memblk) {
char removable = '0';
mem_blk->online = (strncmp(status, "online", 6) == 0);
ga_read_sysfs_file(dirfd, "removable", &removable, 1, &local_err);
if (local_err) {
/* if no 'removable' file, it doesn't support offline mem blk */
if (errno == ENOENT) {
error_free(local_err);
mem_blk->can_offline = false;
} else {
error_propagate(errp, local_err);
}
} else {
mem_blk->can_offline = (removable != '0');
}
} else {
if (mem_blk->online != (strncmp(status, "online", 6) == 0)) {
const char *new_state = mem_blk->online ? "online" : "offline";
ga_write_sysfs_file(dirfd, "state", new_state, strlen(new_state),
&local_err);
if (local_err) {
error_free(local_err);
result->response =
GUEST_MEMORY_BLOCK_RESPONSE_TYPE_OPERATION_FAILED;
goto out2;
}
result->response = GUEST_MEMORY_BLOCK_RESPONSE_TYPE_SUCCESS;
result->has_error_code = false;
} /* otherwise pretend successful re-(on|off)-lining */
}
g_free(status);
close(dirfd);
return;
out2:
g_free(status);
close(dirfd);
out1:
if (!sys2memblk) {
result->has_error_code = true;
result->error_code = errno;
}
}
GuestMemoryBlockList *qmp_guest_get_memory_blocks(Error **errp)
{
GuestMemoryBlockList *head, **tail;
Error *local_err = NULL;
struct dirent *de;
DIR *dp;
head = NULL;
tail = &head;
dp = opendir("/sys/devices/system/memory/");
if (!dp) {
/* it's ok if this happens to be a system that doesn't expose
* memory blocks via sysfs, but otherwise we should report
* an error
*/
if (errno != ENOENT) {
error_setg_errno(errp, errno, "Can't open directory"
"\"/sys/devices/system/memory/\"");
}
return NULL;
}
/* Note: the phys_index of memory block may be discontinuous,
* this is because a memblk is the unit of the Sparse Memory design, which
* allows discontinuous memory ranges (ex. NUMA), so here we should
* traverse the memory block directory.
*/
while ((de = readdir(dp)) != NULL) {
GuestMemoryBlock *mem_blk;
if ((strncmp(de->d_name, "memory", 6) != 0) ||
!(de->d_type & DT_DIR)) {
continue;
}
mem_blk = g_malloc0(sizeof *mem_blk);
/* The d_name is "memoryXXX", phys_index is block id, same as XXX */
mem_blk->phys_index = strtoul(&de->d_name[6], NULL, 10);
mem_blk->has_can_offline = true; /* lolspeak ftw */
transfer_memory_block(mem_blk, true, NULL, &local_err);
if (local_err) {
break;
}
QAPI_LIST_APPEND(tail, mem_blk);
}
closedir(dp);
if (local_err == NULL) {
/* there's no guest with zero memory blocks */
if (head == NULL) {
error_setg(errp, "guest reported zero memory blocks!");
}
return head;
}
qapi_free_GuestMemoryBlockList(head);
error_propagate(errp, local_err);
return NULL;
}
GuestMemoryBlockResponseList *
qmp_guest_set_memory_blocks(GuestMemoryBlockList *mem_blks, Error **errp)
{
GuestMemoryBlockResponseList *head, **tail;
Error *local_err = NULL;
head = NULL;
tail = &head;
while (mem_blks != NULL) {
GuestMemoryBlockResponse *result;
GuestMemoryBlock *current_mem_blk = mem_blks->value;
result = g_malloc0(sizeof(*result));
result->phys_index = current_mem_blk->phys_index;
transfer_memory_block(current_mem_blk, false, result, &local_err);
if (local_err) { /* should never happen */
goto err;
}
QAPI_LIST_APPEND(tail, result);
mem_blks = mem_blks->next;
}
return head;
err:
qapi_free_GuestMemoryBlockResponseList(head);
error_propagate(errp, local_err);
return NULL;
}
GuestMemoryBlockInfo *qmp_guest_get_memory_block_info(Error **errp)
{
Error *local_err = NULL;
char *dirpath;
int dirfd;
char *buf;
GuestMemoryBlockInfo *info;
dirpath = g_strdup_printf("/sys/devices/system/memory/");
dirfd = open(dirpath, O_RDONLY | O_DIRECTORY);
if (dirfd == -1) {
error_setg_errno(errp, errno, "open(\"%s\")", dirpath);
g_free(dirpath);
return NULL;
}
g_free(dirpath);
buf = g_malloc0(20);
ga_read_sysfs_file(dirfd, "block_size_bytes", buf, 20, &local_err);
close(dirfd);
if (local_err) {
g_free(buf);
error_propagate(errp, local_err);
return NULL;
}
info = g_new0(GuestMemoryBlockInfo, 1);
info->size = strtol(buf, NULL, 16); /* the unit is bytes */
g_free(buf);
return info;
}
#define MAX_NAME_LEN 128
static GuestDiskStatsInfoList *guest_get_diskstats(Error **errp)
{
#ifdef CONFIG_LINUX
GuestDiskStatsInfoList *head = NULL, **tail = &head;
const char *diskstats = "/proc/diskstats";
FILE *fp;
size_t n;
char *line = NULL;
fp = fopen(diskstats, "r");
if (fp == NULL) {
error_setg_errno(errp, errno, "open(\"%s\")", diskstats);
return NULL;
}
while (getline(&line, &n, fp) != -1) {
g_autofree GuestDiskStatsInfo *diskstatinfo = NULL;
g_autofree GuestDiskStats *diskstat = NULL;
char dev_name[MAX_NAME_LEN];
unsigned int ios_pgr, tot_ticks, rq_ticks, wr_ticks, dc_ticks, fl_ticks;
unsigned long rd_ios, rd_merges_or_rd_sec, rd_ticks_or_wr_sec, wr_ios;
unsigned long wr_merges, rd_sec_or_wr_ios, wr_sec;
unsigned long dc_ios, dc_merges, dc_sec, fl_ios;
unsigned int major, minor;
int i;
i = sscanf(line, "%u %u %s %lu %lu %lu"
"%lu %lu %lu %lu %u %u %u %u"
"%lu %lu %lu %u %lu %u",
&major, &minor, dev_name,
&rd_ios, &rd_merges_or_rd_sec, &rd_sec_or_wr_ios,
&rd_ticks_or_wr_sec, &wr_ios, &wr_merges, &wr_sec,
&wr_ticks, &ios_pgr, &tot_ticks, &rq_ticks,
&dc_ios, &dc_merges, &dc_sec, &dc_ticks,
&fl_ios, &fl_ticks);
if (i < 7) {
continue;
}
diskstatinfo = g_new0(GuestDiskStatsInfo, 1);
diskstatinfo->name = g_strdup(dev_name);
diskstatinfo->major = major;
diskstatinfo->minor = minor;
diskstat = g_new0(GuestDiskStats, 1);
if (i == 7) {
diskstat->has_read_ios = true;
diskstat->read_ios = rd_ios;
diskstat->has_read_sectors = true;
diskstat->read_sectors = rd_merges_or_rd_sec;
diskstat->has_write_ios = true;
diskstat->write_ios = rd_sec_or_wr_ios;
diskstat->has_write_sectors = true;
diskstat->write_sectors = rd_ticks_or_wr_sec;
}
if (i >= 14) {
diskstat->has_read_ios = true;
diskstat->read_ios = rd_ios;
diskstat->has_read_sectors = true;
diskstat->read_sectors = rd_sec_or_wr_ios;
diskstat->has_read_merges = true;
diskstat->read_merges = rd_merges_or_rd_sec;
diskstat->has_read_ticks = true;
diskstat->read_ticks = rd_ticks_or_wr_sec;
diskstat->has_write_ios = true;
diskstat->write_ios = wr_ios;
diskstat->has_write_sectors = true;
diskstat->write_sectors = wr_sec;
diskstat->has_write_merges = true;
diskstat->write_merges = wr_merges;
diskstat->has_write_ticks = true;
diskstat->write_ticks = wr_ticks;
diskstat->has_ios_pgr = true;
diskstat->ios_pgr = ios_pgr;
diskstat->has_total_ticks = true;
diskstat->total_ticks = tot_ticks;
diskstat->has_weight_ticks = true;
diskstat->weight_ticks = rq_ticks;
}
if (i >= 18) {
diskstat->has_discard_ios = true;
diskstat->discard_ios = dc_ios;
diskstat->has_discard_merges = true;
diskstat->discard_merges = dc_merges;
diskstat->has_discard_sectors = true;
diskstat->discard_sectors = dc_sec;
diskstat->has_discard_ticks = true;
diskstat->discard_ticks = dc_ticks;
}
if (i >= 20) {
diskstat->has_flush_ios = true;
diskstat->flush_ios = fl_ios;
diskstat->has_flush_ticks = true;
diskstat->flush_ticks = fl_ticks;
}
diskstatinfo->stats = g_steal_pointer(&diskstat);
QAPI_LIST_APPEND(tail, diskstatinfo);
diskstatinfo = NULL;
}
free(line);
fclose(fp);
return head;
#else
g_debug("disk stats reporting available only for Linux");
return NULL;
#endif
}
GuestDiskStatsInfoList *qmp_guest_get_diskstats(Error **errp)
{
return guest_get_diskstats(errp);
}
GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp)
{
GuestCpuStatsList *head = NULL, **tail = &head;
const char *cpustats = "/proc/stat";
int clk_tck = sysconf(_SC_CLK_TCK);
FILE *fp;
size_t n;
char *line = NULL;
fp = fopen(cpustats, "r");
if (fp == NULL) {
error_setg_errno(errp, errno, "open(\"%s\")", cpustats);
return NULL;
}
while (getline(&line, &n, fp) != -1) {
GuestCpuStats *cpustat = NULL;
GuestLinuxCpuStats *linuxcpustat;
int i;
unsigned long user, system, idle, iowait, irq, softirq, steal, guest;
unsigned long nice, guest_nice;
char name[64];
i = sscanf(line, "%s %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu",
name, &user, &nice, &system, &idle, &iowait, &irq, &softirq,
&steal, &guest, &guest_nice);
/* drop "cpu 1 2 3 ...", get "cpuX 1 2 3 ..." only */
if ((i == EOF) || strncmp(name, "cpu", 3) || (name[3] == '\0')) {
continue;
}
if (i < 5) {
slog("Parsing cpu stat from %s failed, see \"man proc\"", cpustats);
break;
}
cpustat = g_new0(GuestCpuStats, 1);
cpustat->type = GUEST_CPU_STATS_TYPE_LINUX;
linuxcpustat = &cpustat->u.q_linux;
linuxcpustat->cpu = atoi(&name[3]);
linuxcpustat->user = user * 1000 / clk_tck;
linuxcpustat->nice = nice * 1000 / clk_tck;
linuxcpustat->system = system * 1000 / clk_tck;
linuxcpustat->idle = idle * 1000 / clk_tck;
if (i > 5) {
linuxcpustat->has_iowait = true;
linuxcpustat->iowait = iowait * 1000 / clk_tck;
}
if (i > 6) {
linuxcpustat->has_irq = true;
linuxcpustat->irq = irq * 1000 / clk_tck;
linuxcpustat->has_softirq = true;
linuxcpustat->softirq = softirq * 1000 / clk_tck;
}
if (i > 8) {
linuxcpustat->has_steal = true;
linuxcpustat->steal = steal * 1000 / clk_tck;
}
if (i > 9) {
linuxcpustat->has_guest = true;
linuxcpustat->guest = guest * 1000 / clk_tck;
}
if (i > 10) {
linuxcpustat->has_guest = true;
linuxcpustat->guest = guest * 1000 / clk_tck;
linuxcpustat->has_guestnice = true;
linuxcpustat->guestnice = guest_nice * 1000 / clk_tck;
}
QAPI_LIST_APPEND(tail, cpustat);
}
free(line);
fclose(fp);
return head;
}
#else /* defined(__linux__) */
void qmp_guest_suspend_disk(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
}
void qmp_guest_suspend_ram(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
}
void qmp_guest_suspend_hybrid(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
}
GuestLogicalProcessorList *qmp_guest_get_vcpus(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
int64_t qmp_guest_set_vcpus(GuestLogicalProcessorList *vcpus, Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return -1;
}
GuestMemoryBlockList *qmp_guest_get_memory_blocks(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
GuestMemoryBlockResponseList *
qmp_guest_set_memory_blocks(GuestMemoryBlockList *mem_blks, Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
GuestMemoryBlockInfo *qmp_guest_get_memory_block_info(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif
#ifdef HAVE_GETIFADDRS
static GuestNetworkInterface *
guest_find_interface(GuestNetworkInterfaceList *head,
const char *name)
{
for (; head; head = head->next) {
if (strcmp(head->value->name, name) == 0) {
return head->value;
}
}
return NULL;
}
static int guest_get_network_stats(const char *name,
GuestNetworkInterfaceStat *stats)
{
#ifdef CONFIG_LINUX
int name_len;
char const *devinfo = "/proc/net/dev";
FILE *fp;
char *line = NULL, *colon;
size_t n = 0;
fp = fopen(devinfo, "r");
if (!fp) {
g_debug("failed to open network stats %s: %s", devinfo,
g_strerror(errno));
return -1;
}
name_len = strlen(name);
while (getline(&line, &n, fp) != -1) {
long long dummy;
long long rx_bytes;
long long rx_packets;
long long rx_errs;
long long rx_dropped;
long long tx_bytes;
long long tx_packets;
long long tx_errs;
long long tx_dropped;
char *trim_line;
trim_line = g_strchug(line);
if (trim_line[0] == '\0') {
continue;
}
colon = strchr(trim_line, ':');
if (!colon) {
continue;
}
if (colon - name_len == trim_line &&
strncmp(trim_line, name, name_len) == 0) {
if (sscanf(colon + 1,
"%lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld %lld",
&rx_bytes, &rx_packets, &rx_errs, &rx_dropped,
&dummy, &dummy, &dummy, &dummy,
&tx_bytes, &tx_packets, &tx_errs, &tx_dropped,
&dummy, &dummy, &dummy, &dummy) != 16) {
continue;
}
stats->rx_bytes = rx_bytes;
stats->rx_packets = rx_packets;
stats->rx_errs = rx_errs;
stats->rx_dropped = rx_dropped;
stats->tx_bytes = tx_bytes;
stats->tx_packets = tx_packets;
stats->tx_errs = tx_errs;
stats->tx_dropped = tx_dropped;
fclose(fp);
g_free(line);
return 0;
}
}
fclose(fp);
g_free(line);
g_debug("/proc/net/dev: Interface '%s' not found", name);
#else /* !CONFIG_LINUX */
g_debug("Network stats reporting available only for Linux");
#endif /* !CONFIG_LINUX */
return -1;
}
#ifndef __FreeBSD__
/*
* Fill "buf" with MAC address by ifaddrs. Pointer buf must point to a
* buffer with ETHER_ADDR_LEN length at least.
*
* Returns false in case of an error, otherwise true. "obtained" argument
* is true if a MAC address was obtained successful, otherwise false.
*/
bool guest_get_hw_addr(struct ifaddrs *ifa, unsigned char *buf,
bool *obtained, Error **errp)
{
struct ifreq ifr;
int sock;
*obtained = false;
/* we haven't obtained HW address yet */
sock = socket(PF_INET, SOCK_STREAM, 0);
if (sock == -1) {
error_setg_errno(errp, errno, "failed to create socket");
return false;
}
memset(&ifr, 0, sizeof(ifr));
pstrcpy(ifr.ifr_name, IF_NAMESIZE, ifa->ifa_name);
if (ioctl(sock, SIOCGIFHWADDR, &ifr) == -1) {
/*
* We can't get the hw addr of this interface, but that's not a
* fatal error.
*/
if (errno == EADDRNOTAVAIL) {
/* The interface doesn't have a hw addr (e.g. loopback). */
g_debug("failed to get MAC address of %s: %s",
ifa->ifa_name, strerror(errno));
} else{
g_warning("failed to get MAC address of %s: %s",
ifa->ifa_name, strerror(errno));
}
} else {
#ifdef CONFIG_SOLARIS
memcpy(buf, &ifr.ifr_addr.sa_data, ETHER_ADDR_LEN);
#else
memcpy(buf, &ifr.ifr_hwaddr.sa_data, ETHER_ADDR_LEN);
#endif
*obtained = true;
}
close(sock);
return true;
}
#endif /* __FreeBSD__ */
/*
* Build information about guest interfaces
*/
GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
{
GuestNetworkInterfaceList *head = NULL, **tail = &head;
struct ifaddrs *ifap, *ifa;
if (getifaddrs(&ifap) < 0) {
error_setg_errno(errp, errno, "getifaddrs failed");
goto error;
}
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
GuestNetworkInterface *info;
GuestIpAddressList **address_tail;
GuestIpAddress *address_item = NULL;
GuestNetworkInterfaceStat *interface_stat = NULL;
char addr4[INET_ADDRSTRLEN];
char addr6[INET6_ADDRSTRLEN];
unsigned char mac_addr[ETHER_ADDR_LEN];
bool obtained;
void *p;
g_debug("Processing %s interface", ifa->ifa_name);
info = guest_find_interface(head, ifa->ifa_name);
if (!info) {
info = g_malloc0(sizeof(*info));
info->name = g_strdup(ifa->ifa_name);
QAPI_LIST_APPEND(tail, info);
}
if (!info->has_hardware_address) {
if (!guest_get_hw_addr(ifa, mac_addr, &obtained, errp)) {
goto error;
}
if (obtained) {
info->hardware_address =
g_strdup_printf("%02x:%02x:%02x:%02x:%02x:%02x",
(int) mac_addr[0], (int) mac_addr[1],
(int) mac_addr[2], (int) mac_addr[3],
(int) mac_addr[4], (int) mac_addr[5]);
info->has_hardware_address = true;
}
}
if (ifa->ifa_addr &&
ifa->ifa_addr->sa_family == AF_INET) {
/* interface with IPv4 address */
p = &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
if (!inet_ntop(AF_INET, p, addr4, sizeof(addr4))) {
error_setg_errno(errp, errno, "inet_ntop failed");
goto error;
}
address_item = g_malloc0(sizeof(*address_item));
address_item->ip_address = g_strdup(addr4);
address_item->ip_address_type = GUEST_IP_ADDRESS_TYPE_IPV4;
if (ifa->ifa_netmask) {
/* Count the number of set bits in netmask.
* This is safe as '1' and '0' cannot be shuffled in netmask. */
p = &((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr;
address_item->prefix = ctpop32(((uint32_t *) p)[0]);
}
} else if (ifa->ifa_addr &&
ifa->ifa_addr->sa_family == AF_INET6) {
/* interface with IPv6 address */
p = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
if (!inet_ntop(AF_INET6, p, addr6, sizeof(addr6))) {
error_setg_errno(errp, errno, "inet_ntop failed");
goto error;
}
address_item = g_malloc0(sizeof(*address_item));
address_item->ip_address = g_strdup(addr6);
address_item->ip_address_type = GUEST_IP_ADDRESS_TYPE_IPV6;
if (ifa->ifa_netmask) {
/* Count the number of set bits in netmask.
* This is safe as '1' and '0' cannot be shuffled in netmask. */
p = &((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
address_item->prefix =
ctpop32(((uint32_t *) p)[0]) +
ctpop32(((uint32_t *) p)[1]) +
ctpop32(((uint32_t *) p)[2]) +
ctpop32(((uint32_t *) p)[3]);
}
}
if (!address_item) {
continue;
}
address_tail = &info->ip_addresses;
while (*address_tail) {
address_tail = &(*address_tail)->next;
}
QAPI_LIST_APPEND(address_tail, address_item);
info->has_ip_addresses = true;
if (!info->has_statistics) {
interface_stat = g_malloc0(sizeof(*interface_stat));
if (guest_get_network_stats(info->name, interface_stat) == -1) {
info->has_statistics = false;
g_free(interface_stat);
} else {
info->statistics = interface_stat;
info->has_statistics = true;
}
}
}
freeifaddrs(ifap);
return head;
error:
freeifaddrs(ifap);
qapi_free_GuestNetworkInterfaceList(head);
return NULL;
}
#else
GuestNetworkInterfaceList *qmp_guest_network_get_interfaces(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif /* HAVE_GETIFADDRS */
#if !defined(CONFIG_FSFREEZE)
GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return 0;
}
int64_t qmp_guest_fsfreeze_freeze(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return 0;
}
int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
strList *mountpoints,
Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return 0;
}
int64_t qmp_guest_fsfreeze_thaw(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return 0;
}
GuestDiskInfoList *qmp_guest_get_disks(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
GuestDiskStatsInfoList *qmp_guest_get_diskstats(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif /* CONFIG_FSFREEZE */
#if !defined(CONFIG_FSTRIM)
GuestFilesystemTrimResponse *
qmp_guest_fstrim(bool has_minimum, int64_t minimum, Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif
/* add unsupported commands to the list of blocked RPCs */
GList *ga_command_init_blockedrpcs(GList *blockedrpcs)
{
#if !defined(__linux__)
{
const char *list[] = {
"guest-suspend-disk", "guest-suspend-ram",
"guest-suspend-hybrid", "guest-get-vcpus", "guest-set-vcpus",
"guest-get-memory-blocks", "guest-set-memory-blocks",
"guest-get-memory-block-size", "guest-get-memory-block-info",
NULL};
char **p = (char **)list;
while (*p) {
blockedrpcs = g_list_append(blockedrpcs, g_strdup(*p++));
}
}
#endif
#if !defined(HAVE_GETIFADDRS)
blockedrpcs = g_list_append(blockedrpcs,
g_strdup("guest-network-get-interfaces"));
#endif
#if !defined(CONFIG_FSFREEZE)
{
const char *list[] = {
"guest-get-fsinfo", "guest-fsfreeze-status",
"guest-fsfreeze-freeze", "guest-fsfreeze-freeze-list",
"guest-fsfreeze-thaw", "guest-get-fsinfo",
"guest-get-disks", NULL};
char **p = (char **)list;
while (*p) {
blockedrpcs = g_list_append(blockedrpcs, g_strdup(*p++));
}
}
#endif
#if !defined(CONFIG_FSTRIM)
blockedrpcs = g_list_append(blockedrpcs, g_strdup("guest-fstrim"));
#endif
blockedrpcs = g_list_append(blockedrpcs, g_strdup("guest-get-devices"));
return blockedrpcs;
}
/* register init/cleanup routines for stateful command groups */
void ga_command_state_init(GAState *s, GACommandState *cs)
{
#if defined(CONFIG_FSFREEZE)
ga_command_state_add(cs, NULL, guest_fsfreeze_cleanup);
#endif
}
#ifdef HAVE_UTMPX
#define QGA_MICRO_SECOND_TO_SECOND 1000000
static double ga_get_login_time(struct utmpx *user_info)
{
double seconds = (double)user_info->ut_tv.tv_sec;
double useconds = (double)user_info->ut_tv.tv_usec;
useconds /= QGA_MICRO_SECOND_TO_SECOND;
return seconds + useconds;
}
GuestUserList *qmp_guest_get_users(Error **errp)
{
GHashTable *cache = NULL;
GuestUserList *head = NULL, **tail = &head;
struct utmpx *user_info = NULL;
gpointer value = NULL;
GuestUser *user = NULL;
double login_time = 0;
cache = g_hash_table_new(g_str_hash, g_str_equal);
setutxent();
for (;;) {
user_info = getutxent();
if (user_info == NULL) {
break;
} else if (user_info->ut_type != USER_PROCESS) {
continue;
} else if (g_hash_table_contains(cache, user_info->ut_user)) {
value = g_hash_table_lookup(cache, user_info->ut_user);
user = (GuestUser *)value;
login_time = ga_get_login_time(user_info);
/* We're ensuring the earliest login time to be sent */
if (login_time < user->login_time) {
user->login_time = login_time;
}
continue;
}
user = g_new0(GuestUser, 1);
user->user = g_strdup(user_info->ut_user);
user->login_time = ga_get_login_time(user_info);
g_hash_table_insert(cache, user->user, user);
QAPI_LIST_APPEND(tail, user);
}
endutxent();
g_hash_table_destroy(cache);
return head;
}
#else
GuestUserList *qmp_guest_get_users(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#endif
/* Replace escaped special characters with theire real values. The replacement
* is done in place -- returned value is in the original string.
*/
static void ga_osrelease_replace_special(gchar *value)
{
gchar *p, *p2, quote;
/* Trim the string at first space or semicolon if it is not enclosed in
* single or double quotes. */
if ((value[0] != '"') || (value[0] == '\'')) {
p = strchr(value, ' ');
if (p != NULL) {
*p = 0;
}
p = strchr(value, ';');
if (p != NULL) {
*p = 0;
}
return;
}
quote = value[0];
p2 = value;
p = value + 1;
while (*p != 0) {
if (*p == '\\') {
p++;
switch (*p) {
case '$':
case '\'':
case '"':
case '\\':
case '`':
break;
default:
/* Keep literal backslash followed by whatever is there */
p--;
break;
}
} else if (*p == quote) {
*p2 = 0;
break;
}
*(p2++) = *(p++);
}
}
static GKeyFile *ga_parse_osrelease(const char *fname)
{
gchar *content = NULL;
gchar *content2 = NULL;
GError *err = NULL;
GKeyFile *keys = g_key_file_new();
const char *group = "[os-release]\n";
if (!g_file_get_contents(fname, &content, NULL, &err)) {
slog("failed to read '%s', error: %s", fname, err->message);
goto fail;
}
if (!g_utf8_validate(content, -1, NULL)) {
slog("file is not utf-8 encoded: %s", fname);
goto fail;
}
content2 = g_strdup_printf("%s%s", group, content);
if (!g_key_file_load_from_data(keys, content2, -1, G_KEY_FILE_NONE,
&err)) {
slog("failed to parse file '%s', error: %s", fname, err->message);
goto fail;
}
g_free(content);
g_free(content2);
return keys;
fail:
g_error_free(err);
g_free(content);
g_free(content2);
g_key_file_free(keys);
return NULL;
}
GuestOSInfo *qmp_guest_get_osinfo(Error **errp)
{
GuestOSInfo *info = NULL;
struct utsname kinfo;
GKeyFile *osrelease = NULL;
const char *qga_os_release = g_getenv("QGA_OS_RELEASE");
info = g_new0(GuestOSInfo, 1);
if (uname(&kinfo) != 0) {
error_setg_errno(errp, errno, "uname failed");
} else {
info->has_kernel_version = true;
info->kernel_version = g_strdup(kinfo.version);
info->has_kernel_release = true;
info->kernel_release = g_strdup(kinfo.release);
info->has_machine = true;
info->machine = g_strdup(kinfo.machine);
}
if (qga_os_release != NULL) {
osrelease = ga_parse_osrelease(qga_os_release);
} else {
osrelease = ga_parse_osrelease("/etc/os-release");
if (osrelease == NULL) {
osrelease = ga_parse_osrelease("/usr/lib/os-release");
}
}
if (osrelease != NULL) {
char *value;
#define GET_FIELD(field, osfield) do { \
value = g_key_file_get_value(osrelease, "os-release", osfield, NULL); \
if (value != NULL) { \
ga_osrelease_replace_special(value); \
info->has_ ## field = true; \
info->field = value; \
} \
} while (0)
GET_FIELD(id, "ID");
GET_FIELD(name, "NAME");
GET_FIELD(pretty_name, "PRETTY_NAME");
GET_FIELD(version, "VERSION");
GET_FIELD(version_id, "VERSION_ID");
GET_FIELD(variant, "VARIANT");
GET_FIELD(variant_id, "VARIANT_ID");
#undef GET_FIELD
g_key_file_free(osrelease);
}
return info;
}
GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
{
error_setg(errp, QERR_UNSUPPORTED);
return NULL;
}
#ifndef HOST_NAME_MAX
# ifdef _POSIX_HOST_NAME_MAX
# define HOST_NAME_MAX _POSIX_HOST_NAME_MAX
# else
# define HOST_NAME_MAX 255
# endif
#endif
char *qga_get_host_name(Error **errp)
{
long len = -1;
g_autofree char *hostname = NULL;
#ifdef _SC_HOST_NAME_MAX
len = sysconf(_SC_HOST_NAME_MAX);
#endif /* _SC_HOST_NAME_MAX */
if (len < 0) {
len = HOST_NAME_MAX;
}
/* Unfortunately, gethostname() below does not guarantee a
* NULL terminated string. Therefore, allocate one byte more
* to be sure. */
hostname = g_new0(char, len + 1);
if (gethostname(hostname, len) < 0) {
error_setg_errno(errp, errno,
"cannot get hostname");
return NULL;
}
return g_steal_pointer(&hostname);
}