These new helpers separates the code from the logic used to start new QEMU process with memory state and will make it easier to move qemuSaveImageStartProcess() into qemu_process.c file. Signed-off-by: Pavel Hrdina <phrdina@xxxxxxxxxx> --- src/qemu/qemu_saveimage.c | 155 +++++++++++++++++++++++++++----------- src/qemu/qemu_saveimage.h | 15 ++++ 2 files changed, 128 insertions(+), 42 deletions(-) diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c index 27b95b03ae..95fabee907 100644 --- a/src/qemu/qemu_saveimage.c +++ b/src/qemu/qemu_saveimage.c @@ -247,6 +247,116 @@ qemuSaveImageGetCompressionCommand(virQEMUSaveFormat compression) } +/** + * qemuSaveImageDecompressionStart: + * @data: data from memory state file + * @fd: pointer to FD of memory state file + * @intermediatefd: pointer to FD to store original @fd + * @errbuf: error buffer for @retcmd + * @retcmd: new virCommand pointer + * + * Start process to decompress VM memory state from @fd. If decompression + * is needed the original FD is stored to @intermediatefd and new FD after + * decompression is stored to @fd so caller can use the same variable + * in both cases. + * + * Function qemuSaveImageDecompressionStop() needs to be used to correctly + * stop the process and swap FD to the original state. + * + * Caller is responsible for freeing @retcmd. + * + * Returns -1 on error, 0 on success. + */ +int +qemuSaveImageDecompressionStart(virQEMUSaveData *data, + int *fd, + int *intermediatefd, + char **errbuf, + virCommand **retcmd) +{ + virQEMUSaveHeader *header = &data->header; + g_autoptr(virCommand) cmd = NULL; + + if (header->version != 2) + return 0; + + if (header->compressed == QEMU_SAVE_FORMAT_RAW) + return 0; + + if (!(cmd = qemuSaveImageGetCompressionCommand(header->compressed))) + return -1; + + *intermediatefd = *fd; + *fd = -1; + + virCommandSetInputFD(cmd, *intermediatefd); + virCommandSetOutputFD(cmd, fd); + virCommandSetErrorBuffer(cmd, errbuf); + virCommandDoAsyncIO(cmd); + + if (virCommandRunAsync(cmd, NULL) < 0) { + *fd = *intermediatefd; + *intermediatefd = -1; + return -1; + } + + *retcmd = g_steal_pointer(&cmd); + return 0; +} + + +/** + * qemuSaveImageDecompressionStop: + * @cmd: virCommand pointer + * @fd: pointer to FD of memory state file + * @intermediatefd: pointer to FD to store original @fd + * @errbuf: error buffer for @cmd + * @started: boolean to indicate if QEMU process was started + * @path: path to the memory state file + * + * Stop decompression process and close both @fd and @intermediatefd if + * necessary. + * + * Returns -1 on errro, 0 on success. + */ +int +qemuSaveImageDecompressionStop(virCommand *cmd, + int *fd, + int *intermediatefd, + char *errbuf, + bool started, + const char *path) +{ + int rc = 0; + virErrorPtr orig_err = NULL; + + if (*intermediatefd == -1) + return rc; + + if (!started) { + /* if there was an error setting up qemu, the intermediate + * process will wait forever to write to stdout, so we + * must manually kill it and ignore any error related to + * the process + */ + virErrorPreserveLast(&orig_err); + VIR_FORCE_CLOSE(*intermediatefd); + VIR_FORCE_CLOSE(*fd); + } + + rc = virCommandWait(cmd, NULL); + VIR_DEBUG("Decompression binary stderr: %s", NULLSTR(errbuf)); + virErrorRestore(&orig_err); + + if (VIR_CLOSE(*fd) < 0) { + virReportSystemError(errno, _("cannot close file: %1$s"), path); + rc = -1; + } + + return rc; +} + + /* Helper function to execute a migration to file with a correct save header * the caller needs to make sure that the processors are stopped and do all other * actions besides saving memory */ @@ -595,7 +705,6 @@ qemuSaveImageStartProcess(virConnectPtr conn, { qemuDomainObjPrivate *priv = vm->privateData; g_autoptr(qemuDomainSaveCookie) cookie = NULL; - virQEMUSaveHeader *header = &data->header; VIR_AUTOCLOSE intermediatefd = -1; g_autoptr(virCommand) cmd = NULL; g_autofree char *errbuf = NULL; @@ -605,25 +714,8 @@ qemuSaveImageStartProcess(virConnectPtr conn, virDomainXMLOptionGetSaveCookie(driver->xmlopt)) < 0) return -1; - if ((header->version == 2) && - (header->compressed != QEMU_SAVE_FORMAT_RAW)) { - if (!(cmd = qemuSaveImageGetCompressionCommand(header->compressed))) - return -1; - - intermediatefd = *fd; - *fd = -1; - - virCommandSetInputFD(cmd, intermediatefd); - virCommandSetOutputFD(cmd, fd); - virCommandSetErrorBuffer(cmd, &errbuf); - virCommandDoAsyncIO(cmd); - - if (virCommandRunAsync(cmd, NULL) < 0) { - *fd = intermediatefd; - intermediatefd = -1; - return -1; - } - } + if (qemuSaveImageDecompressionStart(data, fd, &intermediatefd, &errbuf, &cmd) < 0) + return -1; /* No cookie means libvirt which saved the domain was too old to mess up * the CPU definitions. @@ -641,28 +733,7 @@ qemuSaveImageStartProcess(virConnectPtr conn, start_flags) == 0) *started = true; - if (intermediatefd != -1) { - virErrorPtr orig_err = NULL; - - if (!*started) { - /* if there was an error setting up qemu, the intermediate - * process will wait forever to write to stdout, so we - * must manually kill it and ignore any error related to - * the process - */ - virErrorPreserveLast(&orig_err); - VIR_FORCE_CLOSE(intermediatefd); - VIR_FORCE_CLOSE(*fd); - } - - rc = virCommandWait(cmd, NULL); - VIR_DEBUG("Decompression binary stderr: %s", NULLSTR(errbuf)); - virErrorRestore(&orig_err); - } - if (VIR_CLOSE(*fd) < 0) { - virReportSystemError(errno, _("cannot close file: %1$s"), path); - rc = -1; - } + rc = qemuSaveImageDecompressionStop(cmd, fd, &intermediatefd, errbuf, *started, path); virDomainAuditStart(vm, "restored", *started); if (!*started || rc < 0) diff --git a/src/qemu/qemu_saveimage.h b/src/qemu/qemu_saveimage.h index 24249ddf4c..dcee482066 100644 --- a/src/qemu/qemu_saveimage.h +++ b/src/qemu/qemu_saveimage.h @@ -99,6 +99,21 @@ qemuSaveImageGetCompressionProgram(const char *imageFormat, bool use_raw_on_fail) ATTRIBUTE_NONNULL(2); +int +qemuSaveImageDecompressionStart(virQEMUSaveData *data, + int *fd, + int *intermediatefd, + char **errbuf, + virCommand **retcmd); + +int +qemuSaveImageDecompressionStop(virCommand *cmd, + int *fd, + int *intermediatefd, + char *errbuf, + bool started, + const char *path); + int qemuSaveImageCreate(virQEMUDriver *driver, virDomainObj *vm, -- 2.41.0