use this data type to encapsulate the pathname, file descriptor, wrapper, and need to unlink. This will make management of the resources associated with an FD used for QEMU save/restore much easier, reducing the amount of explicit cleanup required. Signed-off-by: Claudio Fontana <cfontana@xxxxxxx> --- src/qemu/qemu_saveimage.c | 112 ++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_saveimage.h | 18 ++++++ 2 files changed, 130 insertions(+) diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c index 7db54f11e1..63c3116407 100644 --- a/src/qemu/qemu_saveimage.c +++ b/src/qemu/qemu_saveimage.c @@ -354,6 +354,118 @@ qemuSaveImageGetCompressionCommand(virQEMUSaveFormat compression) return ret; } +/* + * virQEMUSaveFdInit: initialize a virQEMUSaveFd + * + * @saveFd: the structure to initialize + * @base: the file name + * @oflags the file descriptor open flags + * @cfg: the driver config + * + * Returns -1 on error, 0 on success, + * and in both cases virQEMUSaveFdFini must be called to free resources. + */ +int virQEMUSaveFdInit(virQEMUSaveFd *saveFd, const char *base, + int oflags, virQEMUDriverConfig *cfg) +{ + unsigned int wrapperFlags = VIR_FILE_WRAPPER_NON_BLOCKING; + bool isCreat = oflags & O_CREAT; + bool isDirect = O_DIRECT && (oflags & O_DIRECT); + + if (isDirect) + wrapperFlags |= VIR_FILE_WRAPPER_BYPASS_CACHE; + + saveFd->path = g_strdup(base); + saveFd->wrapper = NULL; + if (isCreat) { + saveFd->fd = virQEMUFileOpenAs(cfg->user, cfg->group, false, saveFd->path, + oflags, &saveFd->need_unlink); + } else { + saveFd->fd = qemuDomainOpenFile(cfg, NULL, saveFd->path, oflags, NULL); + } + if (saveFd->fd < 0) + return -1; + /* + * For O_CREAT, we always add the wrapper, + * and for !O_CREAT, we only add the wrapper if using O_DIRECT. + */ + if (isDirect || isCreat) { + saveFd->wrapper = virFileWrapperFdNew(&saveFd->fd, saveFd->path, wrapperFlags); + if (!saveFd->wrapper) + return -1; + } + return 0; +} + +/* + * virQEMUSaveFdClose: close a virQEMUSaveFd descriptor with normal close. + * + * @saveFd: the saveFd structure with the file descriptors to close. + * @vm: the virDomainObj (necessary to release lock), or NULL. + * + * If saveFd is NULL, the function will return success. + * + * Returns -1 on error, 0 on success. + */ +int virQEMUSaveFdClose(virQEMUSaveFd *saveFd, virDomainObj *vm) +{ + if (!saveFd) + return 0; + + if (VIR_CLOSE(saveFd->fd) < 0) { + virReportSystemError(errno, _("unable to close %s"), saveFd->path); + return -1; + } + if (vm) { + if (qemuDomainFileWrapperFDClose(vm, saveFd->wrapper) < 0) + return -1; + } else { + if (virFileWrapperFdClose(saveFd->wrapper) < 0) + return -1; + } + return 0; +} + +/* + * virQEMUSaveFdFini: finalize a virQEMUSaveFd + * + * @saveFd: the saveFd structure containing the resources to free. + * @vm: the virDomainObj (necessary to release lock for long close ops), or NULL. + * @ret: the current operation result (< 0 is failure) + * + * If saveFd is NULL, the return value will be unchanged. + * + * Returns ret, or -1 if an error is detected. + */ +int virQEMUSaveFdFini(virQEMUSaveFd *saveFd, virDomainObj *vm, int ret) +{ + if (!saveFd) + return ret; + VIR_FORCE_CLOSE(saveFd->fd); + if (vm) { + if (qemuDomainFileWrapperFDClose(vm, saveFd->wrapper) < 0) + ret = -1; + } else { + if (virFileWrapperFdClose(saveFd->wrapper) < 0) + ret = -1; + } + + if (ret < 0 && saveFd->need_unlink && saveFd->path) { + if (unlink(saveFd->path) < 0) { + virReportSystemError(errno, _("cannot remove file: %s"), + saveFd->path); + } + } + if (saveFd->wrapper) { + virFileWrapperFdFree(saveFd->wrapper); + saveFd->wrapper = NULL; + } + + g_free(saveFd->path); + saveFd->path = NULL; + return ret; +} + /* 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 diff --git a/src/qemu/qemu_saveimage.h b/src/qemu/qemu_saveimage.h index 58d0949b9c..21cb1dc78d 100644 --- a/src/qemu/qemu_saveimage.h +++ b/src/qemu/qemu_saveimage.h @@ -54,6 +54,24 @@ struct _virQEMUSaveData { }; +typedef struct _virQEMUSaveFd virQEMUSaveFd; +struct _virQEMUSaveFd { + char *path; + int fd; + bool need_unlink; + virFileWrapperFd *wrapper; +}; + +#define QEMU_SAVEFD_INVALID (virQEMUSaveFd) { .path = NULL, .fd = -1, .need_unlink = false, .wrapper = NULL } + +int virQEMUSaveFdInit(virQEMUSaveFd *saveFd, const char *base, + int oflags, virQEMUDriverConfig *cfg) + ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4); + +int virQEMUSaveFdClose(virQEMUSaveFd *saveFd, virDomainObj *vm); + +int virQEMUSaveFdFini(virQEMUSaveFd *saveFd, virDomainObj *vm, int ret); + virDomainDef * qemuSaveImageUpdateDef(virQEMUDriver *driver, virDomainDef *def, -- 2.35.3