Due to the TTY layer, sending "\n" to the qemu monitor translates into "\r\n" when received. This triggers a bug in older versions of QEMU (KVM <= 33) because the same command is executed twice, and still has problems with fixed QEMU because the "(qemu)" prompt is printed twice. Switch all monitor commands to end with "\r" which avoids both issues. Signed-off-by: Jim Paris <jim@jtan.com> --- src/qemu_driver.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/src/qemu_driver.c b/src/qemu_driver.c index b05c3f6..e13e6a3 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -1755,7 +1755,7 @@ static int qemudDomainSuspend(virDomainPtr dom) { if (vm->state == VIR_DOMAIN_PAUSED) return 0; - if (qemudMonitorCommand(driver, vm, "stop\n", &info) < 0) { + if (qemudMonitorCommand(driver, vm, "stop\r", &info) < 0) { qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, "suspend operation failed"); return -1; } @@ -1780,7 +1780,7 @@ static int qemudDomainResume(virDomainPtr dom) { } if (vm->state == VIR_DOMAIN_RUNNING) return 0; - if (qemudMonitorCommand(driver, vm, "cont\n", &info) < 0) { + if (qemudMonitorCommand(driver, vm, "cont\r", &info) < 0) { qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, "resume operation failed"); return -1; } -- 1.5.3.rc4

If non-negative, uses the supplied fd instead of /dev/null. Update callers accordingly. Signed-off-by: Jim Paris <jim@jtan.com> --- src/openvz_driver.c | 4 ++-- src/qemu_driver.c | 5 +++-- src/util.c | 12 ++++++------ src/util.h | 4 ++-- 4 files changed, 13 insertions(+), 12 deletions(-) diff --git a/src/openvz_driver.c b/src/openvz_driver.c index 84d514c..b994fab 100644 --- a/src/openvz_driver.c +++ b/src/openvz_driver.c @@ -342,7 +342,7 @@ static int openvzListDomains(virConnectPtr conn, int *ids, int nids) { char buf[32]; const char *cmd[] = {VZLIST, "-ovpsid", "-H" , NULL}; - ret = virExec(conn, (char **)cmd, &pid, &outfd, &errfd); + ret = virExec(conn, (char **)cmd, &pid, -1, &outfd, &errfd); if(ret == -1) { error(conn, VIR_ERR_INTERNAL_ERROR, "Could not exec " VZLIST); return (int)NULL; @@ -373,7 +373,7 @@ static int openvzListDefinedDomains(virConnectPtr conn, const char *cmd[] = {VZLIST, "-ovpsid", "-H", NULL}; /* the -S options lists only stopped domains */ - ret = virExec(conn, (char **)cmd, &pid, &outfd, &errfd); + ret = virExec(conn, (char **)cmd, &pid, -1, &outfd, &errfd); if(ret == -1) { error(conn, VIR_ERR_INTERNAL_ERROR, "Could not exec " VZLIST); return (int)NULL; diff --git a/src/qemu_driver.c b/src/qemu_driver.c index e13e6a3..15b94b8 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -655,7 +655,8 @@ static int qemudStartVMDaemon(virConnectPtr conn, qemudLog(QEMUD_WARN, "Unable to write argv to logfile %d: %s", errno, strerror(errno)); - if (virExecNonBlock(conn, argv, &vm->pid, &vm->stdout, &vm->stderr) == 0) { + if (virExecNonBlock(conn, argv, &vm->pid, + -1, &vm->stdout, &vm->stderr) == 0) { vm->id = driver->nextvmid++; vm->state = VIR_DOMAIN_RUNNING; @@ -912,7 +913,7 @@ dhcpStartDhcpDaemon(virConnectPtr conn, if (qemudBuildDnsmasqArgv(conn, network, &argv) < 0) return -1; - ret = virExecNonBlock(conn, argv, &network->dnsmasqPid, NULL, NULL); + ret = virExecNonBlock(conn, argv, &network->dnsmasqPid, -1, NULL, NULL); for (i = 0; argv[i]; i++) free(argv[i]); diff --git a/src/util.c b/src/util.c index f53cfd2..4f80eef 100644 --- a/src/util.c +++ b/src/util.c @@ -79,7 +79,7 @@ static int virSetNonBlock(int fd) { static int _virExec(virConnectPtr conn, char **argv, - int *retpid, int *outfd, int *errfd, int non_block) { + int *retpid, int infd, int *outfd, int *errfd, int non_block) { int pid, null; int pipeout[2] = {-1,-1}; int pipeerr[2] = {-1,-1}; @@ -140,7 +140,7 @@ _virExec(virConnectPtr conn, if (pipeerr[0] > 0 && close(pipeerr[0]) < 0) _exit(1); - if (dup2(null, STDIN_FILENO) < 0) + if (dup2(infd >= 0 ? infd : null, STDIN_FILENO) < 0) _exit(1); if (dup2(pipeout[1] > 0 ? pipeout[1] : null, STDOUT_FILENO) < 0) _exit(1); @@ -176,16 +176,16 @@ _virExec(virConnectPtr conn, int virExec(virConnectPtr conn, char **argv, - int *retpid, int *outfd, int *errfd) { + int *retpid, int infd, int *outfd, int *errfd) { - return(_virExec(conn, argv, retpid, outfd, errfd, 0)); + return(_virExec(conn, argv, retpid, infd, outfd, errfd, 0)); } int virExecNonBlock(virConnectPtr conn, char **argv, - int *retpid, int *outfd, int *errfd) { + int *retpid, int infd, int *outfd, int *errfd) { - return(_virExec(conn, argv, retpid, outfd, errfd, 1)); + return(_virExec(conn, argv, retpid, infd, outfd, errfd, 1)); } diff --git a/src/util.h b/src/util.h index 5b84043..d11e6d9 100644 --- a/src/util.h +++ b/src/util.h @@ -21,6 +21,6 @@ * File created Jul 18, 2007 - Shuveb Hussain <shuveb@binarykarma.com> */ -int virExec(virConnectPtr conn, char **argv, int *retpid, int *outfd, int *errfd); -int virExecNonBlock(virConnectPtr conn, char **argv, int *retpid, int *outfd, int *errfd); +int virExec(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd); +int virExecNonBlock(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd); -- 1.5.3.rc4

Adds new fields in qemu_vm structure. vm->migrateFrom specifies the argument to "-incoming". vm->stdin specifies the file descriptor to pass to virExec as stdin, which will be used for the "-incoming stdio" case. Signed-off-by: Jim Paris <jim@jtan.com> --- src/qemu_conf.c | 13 ++++++++++++- src/qemu_conf.h | 2 ++ src/qemu_driver.c | 4 ++-- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/src/qemu_conf.c b/src/qemu_conf.c index 79dd180..2bbd072 100644 --- a/src/qemu_conf.c +++ b/src/qemu_conf.c @@ -1518,7 +1518,8 @@ int qemudBuildCommandLine(virConnectPtr conn, (vm->def->os.initrd[0] ? 2 : 0) + /* initrd */ (vm->def->os.cmdline[0] ? 2 : 0) + /* cmdline */ (vm->def->graphicsType == QEMUD_GRAPHICS_VNC ? 2 : - (vm->def->graphicsType == QEMUD_GRAPHICS_SDL ? 0 : 1)); /* graphics */ + (vm->def->graphicsType == QEMUD_GRAPHICS_SDL ? 0 : 1)) + /* graphics */ + (vm->migrateFrom[0] ? 3 : 0); /* migrateFrom */ snprintf(memory, sizeof(memory), "%d", vm->def->memory/1024); snprintf(vcpus, sizeof(vcpus), "%d", vm->def->vcpus); @@ -1767,6 +1768,15 @@ int qemudBuildCommandLine(virConnectPtr conn, /* SDL is the default. no args needed */ } + if (vm->migrateFrom[0]) { + if (!((*argv)[++n] = strdup("-S"))) + goto no_memory; + if (!((*argv)[++n] = strdup("-incoming"))) + goto no_memory; + if (!((*argv)[++n] = strdup(vm->migrateFrom))) + goto no_memory; + } + (*argv)[++n] = NULL; return 0; @@ -1884,6 +1894,7 @@ qemudAssignVMDef(virConnectPtr conn, return NULL; } + vm->stdin = -1; vm->stdout = -1; vm->stderr = -1; vm->monitor = -1; diff --git a/src/qemu_conf.h b/src/qemu_conf.h index 60a38b7..4a9b1ae 100644 --- a/src/qemu_conf.h +++ b/src/qemu_conf.h @@ -199,6 +199,7 @@ struct qemud_vm_def { /* Guest VM runtime state */ struct qemud_vm { + int stdin; int stdout; int stderr; int monitor; @@ -212,6 +213,7 @@ struct qemud_vm { char configFile[PATH_MAX]; char autostartLink[PATH_MAX]; + char migrateFrom[PATH_MAX]; struct qemud_vm_def *def; /* The current definition */ struct qemud_vm_def *newDef; /* New definition to activate at shutdown */ diff --git a/src/qemu_driver.c b/src/qemu_driver.c index 15b94b8..e649060 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -656,9 +656,9 @@ static int qemudStartVMDaemon(virConnectPtr conn, errno, strerror(errno)); if (virExecNonBlock(conn, argv, &vm->pid, - -1, &vm->stdout, &vm->stderr) == 0) { + vm->stdin, &vm->stdout, &vm->stderr) == 0) { vm->id = driver->nextvmid++; - vm->state = VIR_DOMAIN_RUNNING; + vm->state = vm->migrateFrom[0] ? VIR_DOMAIN_PAUSED : VIR_DOMAIN_RUNNING; driver->ninactivevms--; driver->nactivevms++; -- 1.5.3.rc4

Use this to escape a shell argument in a commandline passed to qemu. First we need to escape certain characters to get them through the qemu monitor interface. On the shell side, the argument will be enclosed in single quotes, so the only character that needs special treatment is the single quote itself. Signed-off-by: Jim Paris <jim@jtan.com> --- src/qemu_driver.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 66 insertions(+), 0 deletions(-) diff --git a/src/qemu_driver.c b/src/qemu_driver.c index e649060..8125622 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -1855,6 +1855,72 @@ static int qemudDomainGetInfo(virDomainPtr dom, } +static char *qemudEscapeShellArg(const char *in) +{ + int len = 0; + int i, j; + char *out; + + /* To pass through the QEMU monitor, we need to use escape + sequences: \r, \n, \", \\ + + To pass through both QEMU + the shell, we need to escape + the single character ' as the five characters '\\'' + */ + + for (i = 0; in[i] != '\0'; i++) { + switch(in[i]) { + case '\r': + case '\n': + case '"': + case '\\': + len += 2; + break; + case '\'': + len += 5; + break; + default: + len += 1; + break; + } + } + + if ((out = (char *)malloc(len + 1)) == NULL) + return NULL; + + for (i = j = 0; in[i] != '\0'; i++) { + switch(in[i]) { + case '\r': + out[j++] = '\\'; + out[j++] = 'r'; + break; + case '\n': + out[j++] = '\\'; + out[j++] = 'n'; + break; + case '"': + case '\\': + out[j++] = '\\'; + out[j++] = in[i]; + break; + case '\'': + out[j++] = '\''; + out[j++] = '\\'; + out[j++] = '\\'; + out[j++] = '\''; + out[j++] = '\''; + break; + default: + out[j++] = in[i]; + break; + } + } + out[j] = '\0'; + + return out; +} + + static int qemudDomainSave(virDomainPtr dom, const char *path ATTRIBUTE_UNUSED) { struct qemud_driver *driver = (struct qemud_driver *)dom->conn->privateData; -- 1.5.3.rc4

Adds saferead() and safewrite(), which are like read() and write() except that they retry in case of EINTR. Signed-off-by: Jim Paris <jim@jtan.com> --- src/util.c | 37 +++++++++++++++++++++++++++++++++++++ src/util.h | 2 ++ 2 files changed, 39 insertions(+), 0 deletions(-) diff --git a/src/util.c b/src/util.c index 4f80eef..eb57859 100644 --- a/src/util.c +++ b/src/util.c @@ -189,3 +189,40 @@ virExecNonBlock(virConnectPtr conn, return(_virExec(conn, argv, retpid, infd, outfd, errfd, 1)); } +/* Like read(), but restarts after EINTR */ +int saferead(int fd, void *buf, size_t count) +{ + size_t nread = 0; + while (count > 0) { + int r = read(fd, buf, count); + if (r < 0 && errno == EINTR) + continue; + if (r < 0) + return r; + if (r == 0) + return nread; + buf = (unsigned char *)buf + r; + count -= r; + nread += r; + } + return nread; +} + +/* Like write(), but restarts after EINTR */ +ssize_t safewrite(int fd, const void *buf, size_t count) +{ + size_t nwritten = 0; + while (count > 0) { + int r = write(fd, buf, count); + if (r < 0 && errno == EINTR) + continue; + if (r < 0) + return r; + if (r == 0) + return nwritten; + buf = (unsigned char *)buf + r; + count -= r; + nwritten += r; + } + return nwritten; +} diff --git a/src/util.h b/src/util.h index d11e6d9..f69fac8 100644 --- a/src/util.h +++ b/src/util.h @@ -24,3 +24,5 @@ int virExec(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd); int virExecNonBlock(virConnectPtr conn, char **argv, int *retpid, int infd, int *outfd, int *errfd); +int saferead(int fd, void *buf, size_t count); +ssize_t safewrite(int fd, const void *buf, size_t count); -- 1.5.3.rc4

The save file format consists of a header, XML for the domain, and the raw QEMU/KVM migration data stream. Signed-off-by: Jim Paris <jim@jtan.com> --- src/qemu_driver.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 files changed, 107 insertions(+), 5 deletions(-) diff --git a/src/qemu_driver.c b/src/qemu_driver.c index 8125622..f2c4316 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -1921,20 +1921,122 @@ static char *qemudEscapeShellArg(const char *in) } +#define QEMUD_SAVE_MAGIC "LibvirtQemudSave" +#define QEMUD_SAVE_VERSION 1 + +struct qemud_save_header { + char magic[sizeof(QEMUD_SAVE_MAGIC)-1]; + int version; + int xml_len; + int was_running; + int unused[16]; +}; + static int qemudDomainSave(virDomainPtr dom, - const char *path ATTRIBUTE_UNUSED) { + const char *path) { struct qemud_driver *driver = (struct qemud_driver *)dom->conn->privateData; struct qemud_vm *vm = qemudFindVMByID(driver, dom->id); + char *command, *info; + int fd; + char *safe_path; + char *xml; + struct qemud_save_header header; + + memset(&header, 0, sizeof(header)); + memcpy(header.magic, QEMUD_SAVE_MAGIC, sizeof(header.magic)); + header.version = QEMUD_SAVE_VERSION; + if (!vm) { - qemudReportError(dom->conn, dom, NULL, VIR_ERR_INVALID_DOMAIN, "no domain with matching id %d", dom->id); + qemudReportError(dom->conn, dom, NULL, VIR_ERR_INVALID_DOMAIN, + "no domain with matching id %d", dom->id); return -1; } + if (!qemudIsActiveVM(vm)) { - qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, "domain is not running"); + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "domain is not running"); return -1; } - qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, "save is not supported"); - return -1; + + /* Pause */ + if (vm->state == VIR_DOMAIN_RUNNING) { + header.was_running = 1; + if (qemudDomainSuspend(dom) != 0) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "failed to pause domain"); + return -1; + } + } + + /* Get XML for the domain */ + xml = qemudGenerateXML(dom->conn, driver, vm, vm->def, 0); + if (!xml) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "failed to get domain xml"); + return -1; + } + header.xml_len = strlen(xml) + 1; + + /* Write header to file, followed by XML */ + if ((fd = open(path, O_CREAT|O_TRUNC|O_WRONLY, S_IRUSR|S_IWUSR)) < 0) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "failed to create '%s'", path); + free(xml); + return -1; + } + + if (safewrite(fd, &header, sizeof(header)) != sizeof(header)) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "failed to write save header"); + close(fd); + free(xml); + return -1; + } + + if (safewrite(fd, xml, header.xml_len) != header.xml_len) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "failed to write xml"); + close(fd); + free(xml); + return -1; + } + + close(fd); + free(xml); + + /* Migrate to file */ + safe_path = qemudEscapeShellArg(path); + if (!safe_path) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "out of memory"); + return -1; + } + if (asprintf (&command, "migrate \"exec:" + "dd of='%s' oflag=append conv=notrunc 2>/dev/null" + "\"\r", safe_path) == -1) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "out of memory"); + free(safe_path); + return -1; + } + free(safe_path); + + if (qemudMonitorCommand(driver, vm, command, &info) < 0) { + qemudReportError(dom->conn, dom, NULL, VIR_ERR_OPERATION_FAILED, + "migrate operation failed"); + free(command); + return -1; + } + + free(info); + free(command); + + /* Shut it down */ + qemudShutdownVMDaemon(dom->conn, driver, vm); + if (!vm->configFile[0]) + qemudRemoveInactiveVM(driver, vm); + + return 0; } -- 1.5.3.rc4

Signed-off-by: Jim Paris <jim@jtan.com> --- src/qemu_driver.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 files changed, 109 insertions(+), 4 deletions(-) diff --git a/src/qemu_driver.c b/src/qemu_driver.c index f2c4316..b0b6d62 100644 --- a/src/qemu_driver.c +++ b/src/qemu_driver.c @@ -2041,10 +2041,115 @@ static int qemudDomainSave(virDomainPtr dom, static int qemudDomainRestore(virConnectPtr conn, - const char *path ATTRIBUTE_UNUSED) { - /*struct qemud_driver *driver = (struct qemud_driver *)conn->privateData;*/ - qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, "restore is not supported"); - return -1; + const char *path) { + struct qemud_driver *driver = (struct qemud_driver *)conn->privateData; + struct qemud_vm_def *def; + struct qemud_vm *vm; + int fd; + char *xml; + struct qemud_save_header header; + + /* Verify the header and read the XML */ + if ((fd = open(path, O_RDONLY)) < 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "cannot read domain image"); + return -1; + } + + if (saferead(fd, &header, sizeof(header)) != sizeof(header)) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to read qemu header"); + close(fd); + return -1; + } + + if (memcmp(header.magic, QEMUD_SAVE_MAGIC, sizeof(header.magic)) != 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "image magic is incorrect"); + close(fd); + return -1; + } + + if (header.version > QEMUD_SAVE_VERSION) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "image version is not supported (%d > %d)", + header.version, QEMUD_SAVE_VERSION); + close(fd); + return -1; + } + + if ((xml = (char *)malloc(header.xml_len)) == NULL) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "out of memory"); + close(fd); + return -1; + } + + if (saferead(fd, xml, header.xml_len) != header.xml_len) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to read XML"); + close(fd); + free(xml); + return -1; + } + + /* Create a domain from this XML */ + if (!(def = qemudParseVMDef(conn, driver, xml, NULL))) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to parse XML"); + close(fd); + free(xml); + return -1; + } + free(xml); + + /* Ensure the name and UUID don't already exist in an active VM */ + vm = qemudFindVMByUUID(driver, def->uuid); + if (!vm) vm = qemudFindVMByName(driver, def->name); + if (vm && qemudIsActiveVM(vm)) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "domain is already active as '%s'", vm->def->name); + close(fd); + return -1; + } + + if (!(vm = qemudAssignVMDef(conn, driver, def))) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to assign new VM"); + qemudFreeVMDef(def); + close(fd); + return -1; + } + + /* Set the migration source and start it up. */ + snprintf(vm->migrateFrom, sizeof(vm->migrateFrom), "stdio"); + vm->stdin = fd; + + if (qemudStartVMDaemon(conn, driver, vm) < 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to start VM"); + if (!vm->configFile[0]) + qemudRemoveInactiveVM(driver, vm); + close(fd); + return -1; + } + close(fd); + vm->migrateFrom[0] = '\0'; + vm->stdin = -1; + + /* If it was running before, resume it now. */ + if (header.was_running) { + char *info; + if (qemudMonitorCommand(driver, vm, "cont\r", &info) < 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "failed to resume domain"); + return -1; + } + free(info); + vm->state = VIR_DOMAIN_RUNNING; + } + + return 0; } -- 1.5.3.rc4