diff options
| -rw-r--r-- | qapi-schema-guest.json | 24 | ||||
| -rw-r--r-- | qemu-ga.c | 19 | ||||
| -rw-r--r-- | qga/commands-posix.c | 188 | ||||
| -rw-r--r-- | qga/commands-win32.c | 5 |
4 files changed, 235 insertions, 1 deletions
diff --git a/qapi-schema-guest.json b/qapi-schema-guest.json index 706925dea6..f4e0e1d241 100644 --- a/qapi-schema-guest.json +++ b/qapi-schema-guest.json @@ -295,3 +295,27 @@ ## { 'command': 'guest-fsfreeze-thaw', 'returns': 'int' } + +## +# @guest-suspend-disk +# +# Suspend guest to disk. +# +# This command tries to execute the scripts provided by the pm-utils package. +# If it's not available, the suspend operation will be performed by manually +# writing to a sysfs file. +# +# For the best results it's strongly recommended to have the pm-utils +# package installed in the guest. +# +# Returns: nothing on success +# If suspend to disk is not supported, Unsupported +# +# Notes: o This is an asynchronous request. There's no guarantee a response +# will be sent +# o It's strongly recommended to issue the guest-sync command before +# sending commands when the guest resumes +# +# Since: 1.1 +## +{ 'command': 'guest-suspend-disk' } diff --git a/qemu-ga.c b/qemu-ga.c index ba355d8783..1c90e6ef0d 100644 --- a/qemu-ga.c +++ b/qemu-ga.c @@ -17,6 +17,7 @@ #include <getopt.h> #ifndef _WIN32 #include <syslog.h> +#include <sys/wait.h> #endif #include "json-streamer.h" #include "json-parser.h" @@ -73,9 +74,16 @@ static void quit_handler(int sig) } #ifndef _WIN32 +/* reap _all_ terminated children */ +static void child_handler(int sig) +{ + int status; + while (waitpid(-1, &status, WNOHANG) > 0) /* NOTHING */; +} + static gboolean register_signal_handlers(void) { - struct sigaction sigact; + struct sigaction sigact, sigact_chld; int ret; memset(&sigact, 0, sizeof(struct sigaction)); @@ -91,6 +99,15 @@ static gboolean register_signal_handlers(void) g_error("error configuring signal handler: %s", strerror(errno)); return false; } + + memset(&sigact_chld, 0, sizeof(struct sigaction)); + sigact_chld.sa_handler = child_handler; + sigact_chld.sa_flags = SA_NOCLDSTOP; + ret = sigaction(SIGCHLD, &sigact_chld, NULL); + if (ret == -1) { + g_error("error configuring signal handler: %s", strerror(errno)); + } + return true; } #endif diff --git a/qga/commands-posix.c b/qga/commands-posix.c index 126127aae4..af785f5e5d 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -23,6 +23,7 @@ #include <sys/types.h> #include <sys/ioctl.h> +#include <sys/wait.h> #include "qga/guest-agent-core.h" #include "qga-qmp-commands.h" #include "qerror.h" @@ -30,6 +31,22 @@ static GAState *ga_state; +static void reopen_fd_to_null(int fd) +{ + int nullfd; + + nullfd = open("/dev/null", O_RDWR); + if (nullfd < 0) { + return; + } + + dup2(nullfd, fd); + + if (nullfd != fd) { + close(nullfd); + } +} + void qmp_guest_shutdown(bool has_mode, const char *mode, Error **err) { int ret; @@ -517,6 +534,177 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err) } #endif +#define LINUX_SYS_STATE_FILE "/sys/power/state" +#define SUSPEND_SUPPORTED 0 +#define SUSPEND_NOT_SUPPORTED 1 + +/** + * This function forks twice and the information about the mode support + * status is passed to the qemu-ga process via a pipe. + * + * This approach allows us to keep the way we reap terminated children + * in qemu-ga quite simple. + */ +static void bios_supports_mode(const char *pmutils_bin, const char *pmutils_arg, + const char *sysfile_str, Error **err) +{ + pid_t pid; + ssize_t ret; + char *pmutils_path; + int status, pipefds[2]; + + if (pipe(pipefds) < 0) { + error_set(err, QERR_UNDEFINED_ERROR); + return; + } + + pmutils_path = g_find_program_in_path(pmutils_bin); + + pid = fork(); + if (!pid) { + struct sigaction act; + + memset(&act, 0, sizeof(act)); + act.sa_handler = SIG_DFL; + sigaction(SIGCHLD, &act, NULL); + + setsid(); + close(pipefds[0]); + reopen_fd_to_null(0); + reopen_fd_to_null(1); + reopen_fd_to_null(2); + + pid = fork(); + if (!pid) { + int fd; + char buf[32]; /* hopefully big enough */ + + if (pmutils_path) { + execle(pmutils_path, pmutils_bin, pmutils_arg, NULL, environ); + } + + /* + * If we get here either pm-utils is not installed or execle() has + * failed. Let's try the manual method if the caller wants it. + */ + + if (!sysfile_str) { + _exit(SUSPEND_NOT_SUPPORTED); + } + + fd = open(LINUX_SYS_STATE_FILE, O_RDONLY); + if (fd < 0) { + _exit(SUSPEND_NOT_SUPPORTED); + } + + ret = read(fd, buf, sizeof(buf)-1); + if (ret <= 0) { + _exit(SUSPEND_NOT_SUPPORTED); + } + buf[ret] = '\0'; + + if (strstr(buf, sysfile_str)) { + _exit(SUSPEND_SUPPORTED); + } + + _exit(SUSPEND_NOT_SUPPORTED); + } + + if (pid > 0) { + wait(&status); + } else { + status = SUSPEND_NOT_SUPPORTED; + } + + ret = write(pipefds[1], &status, sizeof(status)); + if (ret != sizeof(status)) { + _exit(EXIT_FAILURE); + } + + _exit(EXIT_SUCCESS); + } + + close(pipefds[1]); + g_free(pmutils_path); + + if (pid < 0) { + error_set(err, QERR_UNDEFINED_ERROR); + goto out; + } + + ret = read(pipefds[0], &status, sizeof(status)); + if (ret == sizeof(status) && WIFEXITED(status) && + WEXITSTATUS(status) == SUSPEND_SUPPORTED) { + goto out; + } + + error_set(err, QERR_UNSUPPORTED); + +out: + close(pipefds[0]); +} + +static void guest_suspend(const char *pmutils_bin, const char *sysfile_str, + Error **err) +{ + pid_t pid; + char *pmutils_path; + + pmutils_path = g_find_program_in_path(pmutils_bin); + + pid = fork(); + if (pid == 0) { + /* child */ + int fd; + + setsid(); + reopen_fd_to_null(0); + reopen_fd_to_null(1); + reopen_fd_to_null(2); + + if (pmutils_path) { + execle(pmutils_path, pmutils_bin, NULL, environ); + } + + /* + * If we get here either pm-utils is not installed or execle() has + * failed. Let's try the manual method if the caller wants it. + */ + + if (!sysfile_str) { + _exit(EXIT_FAILURE); + } + + 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); + } + + g_free(pmutils_path); + + if (pid < 0) { + error_set(err, QERR_UNDEFINED_ERROR); + return; + } +} + +void qmp_guest_suspend_disk(Error **err) +{ + bios_supports_mode("pm-is-supported", "--hibernate", "disk", err); + if (error_is_set(err)) { + return; + } + + guest_suspend("pm-hibernate", "disk", err); +} + /* register init/cleanup routines for stateful command groups */ void ga_command_state_init(GAState *s, GACommandState *cs) { diff --git a/qga/commands-win32.c b/qga/commands-win32.c index 4aa0f0d1e4..c688476c89 100644 --- a/qga/commands-win32.c +++ b/qga/commands-win32.c @@ -124,6 +124,11 @@ int64_t qmp_guest_fsfreeze_thaw(Error **err) return 0; } +void qmp_guest_suspend_disk(Error **err) +{ + error_set(err, QERR_UNSUPPORTED); +} + /* register init/cleanup routines for stateful command groups */ void ga_command_state_init(GAState *s, GACommandState *cs) { |