/* * storage_backend.c: internal storage driver backend contract * * Copyright (C) 2007-2010 Red Hat, Inc. * Copyright (C) 2007-2008 Daniel P. Berrange * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * Author: Daniel P. Berrange */ #include #include #include #if HAVE_REGEX_H # include #endif #include #include #include #include #include #include #include #include #if HAVE_SELINUX # include #endif #include "datatypes.h" #include "virterror_internal.h" #include "util.h" #include "memory.h" #include "internal.h" #include "secret_conf.h" #include "uuid.h" #include "storage_file.h" #include "storage_backend.h" #include "logging.h" #if WITH_STORAGE_LVM # include "storage_backend_logical.h" #endif #if WITH_STORAGE_ISCSI # include "storage_backend_iscsi.h" #endif #if WITH_STORAGE_SCSI # include "storage_backend_scsi.h" #endif #if WITH_STORAGE_MPATH # include "storage_backend_mpath.h" #endif #if WITH_STORAGE_DISK # include "storage_backend_disk.h" #endif #if WITH_STORAGE_DIR # include "storage_backend_fs.h" #endif #define VIR_FROM_THIS VIR_FROM_STORAGE static virStorageBackendPtr backends[] = { #if WITH_STORAGE_DIR &virStorageBackendDirectory, #endif #if WITH_STORAGE_FS &virStorageBackendFileSystem, &virStorageBackendNetFileSystem, #endif #if WITH_STORAGE_LVM &virStorageBackendLogical, #endif #if WITH_STORAGE_ISCSI &virStorageBackendISCSI, #endif #if WITH_STORAGE_SCSI &virStorageBackendSCSI, #endif #if WITH_STORAGE_MPATH &virStorageBackendMpath, #endif #if WITH_STORAGE_DISK &virStorageBackendDisk, #endif NULL }; static int track_allocation_progress = 0; enum { TOOL_QEMU_IMG, TOOL_KVM_IMG, TOOL_QCOW_CREATE, }; static int ATTRIBUTE_NONNULL (2) virStorageBackendCopyToFD(virStorageVolDefPtr vol, virStorageVolDefPtr inputvol, int fd, unsigned long long *total, int is_dest_file) { int inputfd = -1; int amtread = -1; int ret = -1; unsigned long long remain; size_t bytes = 1024 * 1024; char zerobuf[512]; char *buf = NULL; if ((inputfd = open(inputvol->target.path, O_RDONLY)) < 0) { virReportSystemError(errno, _("could not open input path '%s'"), inputvol->target.path); goto cleanup; } bzero(&zerobuf, sizeof(zerobuf)); if (VIR_ALLOC_N(buf, bytes) < 0) { virReportOOMError(); goto cleanup; } remain = *total; while (amtread != 0) { int amtleft; if (remain < bytes) bytes = remain; if ((amtread = saferead(inputfd, buf, bytes)) < 0) { virReportSystemError(errno, _("failed reading from file '%s'"), inputvol->target.path); goto cleanup; } remain -= amtread; /* Loop over amt read in 512 byte increments, looking for sparse * blocks */ amtleft = amtread; do { int interval = ((512 > amtleft) ? amtleft : 512); int offset = amtread - amtleft; if (is_dest_file && memcmp(buf+offset, zerobuf, interval) == 0) { if (lseek(fd, interval, SEEK_CUR) < 0) { virReportSystemError(errno, _("cannot extend file '%s'"), vol->target.path); goto cleanup; } } else if (safewrite(fd, buf+offset, interval) < 0) { virReportSystemError(errno, _("failed writing to file '%s'"), vol->target.path); goto cleanup; } } while ((amtleft -= 512) > 0); } if (inputfd != -1 && close(inputfd) < 0) { virReportSystemError(errno, _("cannot close file '%s'"), inputvol->target.path); goto cleanup; } inputfd = -1; *total -= remain; ret = 0; cleanup: if (inputfd != -1) close(inputfd); VIR_FREE(buf); return ret; } static int virStorageBackendCreateBlockFrom(virConnectPtr conn ATTRIBUTE_UNUSED, virStoragePoolObjPtr pool ATTRIBUTE_UNUSED, virStorageVolDefPtr vol, virStorageVolDefPtr inputvol, unsigned int flags ATTRIBUTE_UNUSED) { int fd = -1; int ret = -1; unsigned long long remain; struct stat st; gid_t gid; uid_t uid; if ((fd = open(vol->target.path, O_RDWR)) < 0) { virReportSystemError(errno, _("cannot create path '%s'"), vol->target.path); goto cleanup; } remain = vol->allocation; if (inputvol) { int res = virStorageBackendCopyToFD(vol, inputvol, fd, &remain, 0); if (res < 0) goto cleanup; } if (fstat(fd, &st) == -1) { ret = errno; virReportSystemError(errno, _("stat of '%s' failed"), vol->target.path); goto cleanup; } uid = (vol->target.perms.uid != st.st_uid) ? vol->target.perms.uid : -1; gid = (vol->target.perms.gid != st.st_gid) ? vol->target.perms.gid : -1; if (((uid != -1) || (gid != -1)) && (fchown(fd, uid, gid) < 0)) { virReportSystemError(errno, _("cannot chown '%s' to (%u, %u)"), vol->target.path, uid, gid); goto cleanup; } if (fchmod(fd, vol->target.perms.mode) < 0) { virReportSystemError(errno, _("cannot set mode of '%s' to %04o"), vol->target.path, vol->target.perms.mode); goto cleanup; } if (close(fd) < 0) { virReportSystemError(errno, _("cannot close file '%s'"), vol->target.path); goto cleanup; } fd = -1; ret = 0; cleanup: if (fd != -1) close(fd); return ret; } struct createRawFileOpHookData { virStorageVolDefPtr vol; virStorageVolDefPtr inputvol; }; static int createRawFileOpHook(int fd, void *data) { struct createRawFileOpHookData *hdata = data; int ret = 0; unsigned long long remain; /* Seek to the final size, so the capacity is available upfront * for progress reporting */ if (ftruncate(fd, hdata->vol->capacity) < 0) { ret = errno; virReportSystemError(errno, _("cannot extend file '%s'"), hdata->vol->target.path); goto cleanup; } remain = hdata->vol->allocation; if (hdata->inputvol) { int res = virStorageBackendCopyToFD(hdata->vol, hdata->inputvol, fd, &remain, 1); if (res < 0) ret = -res; goto cleanup; } if (remain) { if (track_allocation_progress) { while (remain) { /* Allocate in chunks of 512MiB: big-enough chunk * size and takes approx. 9s on ext3. A progress * update every 9s is a fair-enough trade-off */ unsigned long long bytes = 512 * 1024 * 1024; if (bytes > remain) bytes = remain; if (safezero(fd, 0, hdata->vol->allocation - remain, bytes) != 0) { ret = errno; virReportSystemError(errno, _("cannot fill file '%s'"), hdata->vol->target.path); goto cleanup; } remain -= bytes; } } else { /* No progress bars to be shown */ if (safezero(fd, 0, 0, remain) != 0) { ret = errno; virReportSystemError(errno, _("cannot fill file '%s'"), hdata->vol->target.path); goto cleanup; } } if (fsync(fd) < 0) { ret = errno; virReportSystemError(errno, _("cannot sync data to file '%s'"), hdata->vol->target.path); goto cleanup; } } cleanup: return ret; } int virStorageBackendCreateRaw(virConnectPtr conn ATTRIBUTE_UNUSED, virStoragePoolObjPtr pool, virStorageVolDefPtr vol, virStorageVolDefPtr inputvol, unsigned int flags ATTRIBUTE_UNUSED) { int ret = -1; int createstat; struct createRawFileOpHookData hdata = { vol, inputvol }; if (vol->target.encryption != NULL) { virStorageReportError(VIR_ERR_NO_SUPPORT, "%s", _("storage pool does not support encrypted " "volumes")); goto cleanup; } uid_t uid = (vol->target.perms.uid == -1) ? getuid() : vol->target.perms.uid; gid_t gid = (vol->target.perms.gid == -1) ? getgid() : vol->target.perms.gid; if ((createstat = virFileOperation(vol->target.path, O_RDWR | O_CREAT | O_EXCL, vol->target.perms.mode, uid, gid, createRawFileOpHook, &hdata, VIR_FILE_OP_FORCE_PERMS | (pool->def->type == VIR_STORAGE_POOL_NETFS ? VIR_FILE_OP_AS_UID : 0))) < 0) { virReportSystemError(createstat, _("cannot create path '%s'"), vol->target.path); goto cleanup; } ret = 0; cleanup: return ret; } static int virStorageGenerateSecretUUID(virConnectPtr conn, unsigned char *uuid) { unsigned attempt; for (attempt = 0; attempt < 65536; attempt++) { virSecretPtr tmp; if (virUUIDGenerate(uuid) < 0) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("unable to generate uuid")); return -1; } tmp = conn->secretDriver->lookupByUUID(conn, uuid); if (tmp == NULL) return 0; virSecretFree(tmp); } virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("too many conflicts when generating an uuid")); return -1; } static int virStorageGenerateQcowEncryption(virConnectPtr conn, virStorageVolDefPtr vol) { virSecretDefPtr def = NULL; virBuffer buf = VIR_BUFFER_INITIALIZER; virStorageEncryptionPtr enc; virStorageEncryptionSecretPtr enc_secret = NULL; virSecretPtr secret = NULL; char *xml; unsigned char value[VIR_STORAGE_QCOW_PASSPHRASE_SIZE]; int ret = -1; if (conn->secretDriver == NULL || conn->secretDriver->lookupByUUID == NULL || conn->secretDriver->defineXML == NULL || conn->secretDriver->setValue == NULL) { virStorageReportError(VIR_ERR_NO_SUPPORT, "%s", _("secret storage not supported")); goto cleanup; } enc = vol->target.encryption; if (enc->nsecrets != 0) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("secrets already defined")); goto cleanup; } if (VIR_ALLOC(enc_secret) < 0 || VIR_REALLOC_N(enc->secrets, 1) < 0 || VIR_ALLOC(def) < 0) { virReportOOMError(); goto cleanup; } def->ephemeral = 0; def->private = 0; if (virStorageGenerateSecretUUID(conn, def->uuid) < 0) goto cleanup; def->usage_type = VIR_SECRET_USAGE_TYPE_VOLUME; def->usage.volume = strdup(vol->target.path); if (def->usage.volume == NULL) { virReportOOMError(); goto cleanup; } xml = virSecretDefFormat(def); virSecretDefFree(def); def = NULL; if (xml == NULL) goto cleanup; secret = conn->secretDriver->defineXML(conn, xml, 0); if (secret == NULL) { VIR_FREE(xml); goto cleanup; } VIR_FREE(xml); if (virStorageGenerateQcowPassphrase(value) < 0) goto cleanup; if (conn->secretDriver->setValue(secret, value, sizeof(value), 0) < 0) goto cleanup; enc_secret->type = VIR_STORAGE_ENCRYPTION_SECRET_TYPE_PASSPHRASE; memcpy(enc_secret->uuid, secret->uuid, VIR_UUID_BUFLEN); enc->format = VIR_STORAGE_ENCRYPTION_FORMAT_QCOW; enc->secrets[0] = enc_secret; /* Space for secrets[0] allocated above */ enc_secret = NULL; enc->nsecrets = 1; ret = 0; cleanup: if (secret != NULL) { if (ret != 0 && conn->secretDriver->undefine != NULL) conn->secretDriver->undefine(secret); virSecretFree(secret); } virBufferFreeAndReset(&buf); virSecretDefFree(def); VIR_FREE(enc_secret); return ret; } static int virStorageBuildSetUIDHook(void *data) { virStorageVolDefPtr vol = data; if ((vol->target.perms.gid != -1) && (setgid(vol->target.perms.gid) != 0)) { virReportSystemError(errno, _("Cannot set gid to %u before creating %s"), vol->target.perms.gid, vol->target.path); return -1; } if ((vol->target.perms.uid != -1) && (setuid(vol->target.perms.uid) != 0)) { virReportSystemError(errno, _("Cannot set uid to %u before creating %s"), vol->target.perms.uid, vol->target.path); return -1; } return 0; } static int virStorageBackendCreateExecCommand(virStoragePoolObjPtr pool, virStorageVolDefPtr vol, const char **cmdargv) { struct stat st; gid_t gid; uid_t uid; int filecreated = 0; if ((pool->def->type == VIR_STORAGE_POOL_NETFS) && (((getuid() == 0) && (vol->target.perms.uid != -1) && (vol->target.perms.uid != 0)) || ((vol->target.perms.gid != -1) && (vol->target.perms.gid != getgid())))) { if (virRunWithHook(cmdargv, virStorageBuildSetUIDHook, vol, NULL) == 0) { /* command was successfully run, check if the file was created */ if (stat(vol->target.path, &st) >=0) filecreated = 1; } } if (!filecreated) { if (virRun(cmdargv, NULL) < 0) { virReportSystemError(errno, _("Cannot run %s to create %s"), cmdargv[0], vol->target.path); return -1; } if (stat(vol->target.path, &st) < 0) { virReportSystemError(errno, _("%s failed to create %s"), cmdargv[0], vol->target.path); return -1; } } uid = (vol->target.perms.uid != st.st_uid) ? vol->target.perms.uid : -1; gid = (vol->target.perms.gid != st.st_gid) ? vol->target.perms.gid : -1; if (((uid != -1) || (gid != -1)) && (chown(vol->target.path, uid, gid) < 0)) { virReportSystemError(errno, _("cannot chown %s to (%u, %u)"), vol->target.path, uid, gid); return -1; } if (chmod(vol->target.path, vol->target.perms.mode) < 0) { virReportSystemError(errno, _("cannot set mode of '%s' to %04o"), vol->target.path, vol->target.perms.mode); return -1; } return 0; } enum { QEMU_IMG_BACKING_FORMAT_NONE = 0, QEMU_IMG_BACKING_FORMAT_FLAG, QEMU_IMG_BACKING_FORMAT_OPTIONS, }; static int virStorageBackendQEMUImgBackingFormat(const char *qemuimg) { const char *const qemuarg[] = { qemuimg, "-h", NULL }; const char *const qemuenv[] = { "LC_ALL=C", NULL }; pid_t child = 0; int status; int newstdout = -1; char *help = NULL; enum { MAX_HELP_OUTPUT_SIZE = 1024*8 }; int len; char *start; char *end; char *tmp; int ret = -1; if (virExec(qemuarg, qemuenv, NULL, &child, -1, &newstdout, NULL, VIR_EXEC_CLEAR_CAPS) < 0) goto cleanup; if ((len = virFileReadLimFD(newstdout, MAX_HELP_OUTPUT_SIZE, &help)) < 0) { virReportSystemError(errno, _("Unable to read '%s -h' output"), qemuimg); goto cleanup; } start = strstr(help, " create "); end = strstr(start, "\n"); if ((tmp = strstr(start, "-F fmt")) && tmp < end) ret = QEMU_IMG_BACKING_FORMAT_FLAG; else if ((tmp = strstr(start, "[-o options]")) && tmp < end) ret = QEMU_IMG_BACKING_FORMAT_OPTIONS; else ret = QEMU_IMG_BACKING_FORMAT_NONE; cleanup: VIR_FREE(help); close(newstdout); rewait: if (child) { if (waitpid(child, &status, 0) != child) { if (errno == EINTR) goto rewait; VIR_ERROR(_("Unexpected exit status from qemu %d pid %lu"), WEXITSTATUS(status), (unsigned long)child); } if (WEXITSTATUS(status) != 0) { VIR_WARN("Unexpected exit status '%d', qemu probably failed", WEXITSTATUS(status)); } } return ret; } static int virStorageBackendCreateQemuImg(virConnectPtr conn, virStoragePoolObjPtr pool, virStorageVolDefPtr vol, virStorageVolDefPtr inputvol, unsigned int flags ATTRIBUTE_UNUSED) { int ret = -1; char size[100]; char *create_tool; const char *type = virStorageFileFormatTypeToString(vol->target.format); const char *backingType = vol->backingStore.path ? virStorageFileFormatTypeToString(vol->backingStore.format) : NULL; const char *inputBackingPath = (inputvol ? inputvol->backingStore.path : NULL); const char *inputPath = inputvol ? inputvol->target.path : NULL; /* Treat input block devices as 'raw' format */ const char *inputType = inputPath ? virStorageFileFormatTypeToString(inputvol->type == VIR_STORAGE_VOL_BLOCK ? VIR_STORAGE_FILE_RAW : inputvol->target.format) : NULL; if (type == NULL) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("unknown storage vol type %d"), vol->target.format); return -1; } if (inputvol && inputType == NULL) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("unknown storage vol type %d"), inputvol->target.format); return -1; } if (vol->backingStore.path) { /* XXX: Not strictly required: qemu-img has an option a different * backing store, not really sure what use it serves though, and it * may cause issues with lvm. Untested essentially. */ if (inputvol && (!inputBackingPath || STRNEQ(inputBackingPath, vol->backingStore.path))) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("a different backing store can not " "be specified.")); return -1; } if (backingType == NULL) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("unknown storage vol backing store type %d"), vol->backingStore.format); return -1; } if (access(vol->backingStore.path, R_OK) != 0) { virReportSystemError(errno, _("inaccessible backing store volume %s"), vol->backingStore.path); return -1; } } if (vol->target.encryption != NULL) { virStorageEncryptionPtr enc; if (vol->target.format != VIR_STORAGE_FILE_QCOW && vol->target.format != VIR_STORAGE_FILE_QCOW2) { virStorageReportError(VIR_ERR_NO_SUPPORT, _("qcow volume encryption unsupported with " "volume format %s"), type); return -1; } enc = vol->target.encryption; if (enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_QCOW && enc->format != VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT) { virStorageReportError(VIR_ERR_NO_SUPPORT, _("unsupported volume encryption format %d"), vol->target.encryption->format); return -1; } if (enc->nsecrets > 1) { virStorageReportError(VIR_ERR_INVALID_STORAGE_VOL, "%s", _("too many secrets for qcow encryption")); return -1; } if (enc->format == VIR_STORAGE_ENCRYPTION_FORMAT_DEFAULT || enc->nsecrets == 0) { if (virStorageGenerateQcowEncryption(conn, vol) < 0) return -1; } } /* Size in KB */ snprintf(size, sizeof(size), "%lluK", vol->capacity/1024); /* KVM is usually ahead of qemu on features, so try that first */ create_tool = virFindFileInPath("kvm-img"); if (!create_tool) create_tool = virFindFileInPath("qemu-img"); if (!create_tool) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("unable to find kvm-img or qemu-img")); return -1; } if (inputvol) { const char *imgargv[] = { create_tool, "convert", "-f", inputType, "-O", type, inputPath, vol->target.path, NULL, }; ret = virStorageBackendCreateExecCommand(pool, vol, imgargv); } else if (vol->backingStore.path) { const char *imgargv[] = { create_tool, "create", "-f", type, "-b", vol->backingStore.path, NULL, NULL, NULL, NULL, NULL, NULL }; int imgformat = virStorageBackendQEMUImgBackingFormat(create_tool); char *optflag = NULL; if (imgformat < 0) goto cleanup; switch (imgformat) { case QEMU_IMG_BACKING_FORMAT_FLAG: imgargv[6] = "-F"; imgargv[7] = backingType; imgargv[8] = vol->target.path; imgargv[9] = size; if (vol->target.encryption != NULL) imgargv[10] = "-e"; break; case QEMU_IMG_BACKING_FORMAT_OPTIONS: if (virAsprintf(&optflag, "backing_fmt=%s", backingType) < 0) { virReportOOMError(); goto cleanup; } imgargv[6] = "-o"; imgargv[7] = optflag; imgargv[8] = vol->target.path; imgargv[9] = size; if (vol->target.encryption != NULL) imgargv[10] = "-e"; break; default: VIR_INFO("Unable to set backing store format for %s with %s", vol->target.path, create_tool); imgargv[6] = vol->target.path; imgargv[7] = size; if (vol->target.encryption != NULL) imgargv[8] = "-e"; } ret = virStorageBackendCreateExecCommand(pool, vol, imgargv); VIR_FREE(optflag); } else { /* The extra NULL field is for indicating encryption (-e). */ const char *imgargv[] = { create_tool, "create", "-f", type, vol->target.path, size, NULL, NULL }; if (vol->target.encryption != NULL) imgargv[6] = "-e"; ret = virStorageBackendCreateExecCommand(pool, vol, imgargv); } cleanup: VIR_FREE(create_tool); return ret; } /* * Xen removed the fully-functional qemu-img, and replaced it * with a partially functional qcow-create. Go figure ??!? */ static int virStorageBackendCreateQcowCreate(virConnectPtr conn ATTRIBUTE_UNUSED, virStoragePoolObjPtr pool, virStorageVolDefPtr vol, virStorageVolDefPtr inputvol, unsigned int flags ATTRIBUTE_UNUSED) { int ret; char size[100]; const char *imgargv[4]; if (inputvol) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("cannot copy from volume with qcow-create")); return -1; } if (vol->target.format != VIR_STORAGE_FILE_QCOW2) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("unsupported storage vol type %d"), vol->target.format); return -1; } if (vol->backingStore.path != NULL) { virStorageReportError(VIR_ERR_NO_SUPPORT, "%s", _("copy-on-write image not supported with " "qcow-create")); return -1; } if (vol->target.encryption != NULL) { virStorageReportError(VIR_ERR_NO_SUPPORT, "%s", _("encrypted volumes not supported with " "qcow-create")); return -1; } /* Size in MB - yes different units to qemu-img :-( */ snprintf(size, sizeof(size), "%llu", vol->capacity/1024/1024); imgargv[0] = virFindFileInPath("qcow-create"); imgargv[1] = size; imgargv[2] = vol->target.path; imgargv[3] = NULL; ret = virStorageBackendCreateExecCommand(pool, vol, imgargv); VIR_FREE(imgargv[0]); return ret; } virStorageBackendBuildVolFrom virStorageBackendFSImageToolTypeToFunc(int tool_type) { switch (tool_type) { case TOOL_KVM_IMG: case TOOL_QEMU_IMG: return virStorageBackendCreateQemuImg; case TOOL_QCOW_CREATE: return virStorageBackendCreateQcowCreate; default: virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("Unknown file create tool type '%d'."), tool_type); } return NULL; } int virStorageBackendFindFSImageTool(char **tool) { int tool_type = -1; char *tmp = NULL; if ((tmp = virFindFileInPath("kvm-img")) != NULL) { tool_type = TOOL_KVM_IMG; } else if ((tmp = virFindFileInPath("qemu-img")) != NULL) { tool_type = TOOL_QEMU_IMG; } else if ((tmp = virFindFileInPath("qcow-create")) != NULL) { tool_type = TOOL_QCOW_CREATE; } if (tool) *tool = tmp; else VIR_FREE(tmp); return tool_type; } virStorageBackendBuildVolFrom virStorageBackendGetBuildVolFromFunction(virStorageVolDefPtr vol, virStorageVolDefPtr inputvol) { int tool_type; if (!inputvol) return NULL; /* If either volume is a non-raw file vol, we need to use an external * tool for converting */ if ((vol->type == VIR_STORAGE_VOL_FILE && vol->target.format != VIR_STORAGE_FILE_RAW) || (inputvol->type == VIR_STORAGE_VOL_FILE && inputvol->target.format != VIR_STORAGE_FILE_RAW)) { if ((tool_type = virStorageBackendFindFSImageTool(NULL)) < 0) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("creation of non-raw file images is " "not supported without qemu-img.")); return NULL; } return virStorageBackendFSImageToolTypeToFunc(tool_type); } if (vol->type == VIR_STORAGE_VOL_BLOCK) return virStorageBackendCreateBlockFrom; else return virStorageBackendCreateRaw; } virStorageBackendPtr virStorageBackendForType(int type) { unsigned int i; for (i = 0; backends[i]; i++) if (backends[i]->type == type) return backends[i]; virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("missing backend for pool type %d"), type); return NULL; } /* * Allows caller to silently ignore files with improper mode * * Returns -1 on error, -2 if file mode is unexpected. */ int virStorageBackendVolOpenCheckMode(const char *path, unsigned int flags) { int fd, mode = 0; struct stat sb; if ((fd = open(path, O_RDONLY|O_NONBLOCK|O_NOCTTY)) < 0) { virReportSystemError(errno, _("cannot open volume '%s'"), path); return -1; } if (fstat(fd, &sb) < 0) { virReportSystemError(errno, _("cannot stat file '%s'"), path); close(fd); return -1; } if (S_ISREG(sb.st_mode)) mode = VIR_STORAGE_VOL_OPEN_REG; else if (S_ISCHR(sb.st_mode)) mode = VIR_STORAGE_VOL_OPEN_CHAR; else if (S_ISBLK(sb.st_mode)) mode = VIR_STORAGE_VOL_OPEN_BLOCK; if (!(mode & flags)) { close(fd); if (mode & VIR_STORAGE_VOL_OPEN_ERROR) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("unexpected storage mode for '%s'"), path); return -1; } return -2; } return fd; } int virStorageBackendVolOpen(const char *path) { return virStorageBackendVolOpenCheckMode(path, VIR_STORAGE_VOL_OPEN_DEFAULT); } int virStorageBackendUpdateVolTargetInfo(virStorageVolTargetPtr target, unsigned long long *allocation, unsigned long long *capacity) { int ret, fd; if ((ret = virStorageBackendVolOpen(target->path)) < 0) return ret; fd = ret; ret = virStorageBackendUpdateVolTargetInfoFD(target, fd, allocation, capacity); close(fd); return ret; } int virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol, int withCapacity) { int ret; if ((ret = virStorageBackendUpdateVolTargetInfo(&vol->target, &vol->allocation, withCapacity ? &vol->capacity : NULL)) < 0) return ret; if (vol->backingStore.path && (ret = virStorageBackendUpdateVolTargetInfo(&vol->backingStore, NULL, NULL)) < 0) return ret; return 0; } /* * virStorageBackendUpdateVolTargetInfoFD: * @conn: connection to report errors on * @target: target definition ptr of volume to update * @fd: fd of storage volume to update, via virStorageBackendOpenVol* * @allocation: If not NULL, updated allocation information will be stored * @capacity: If not NULL, updated capacity info will be stored * * Returns 0 for success, -1 on a legitimate error condition. */ int virStorageBackendUpdateVolTargetInfoFD(virStorageVolTargetPtr target, int fd, unsigned long long *allocation, unsigned long long *capacity) { struct stat sb; #if HAVE_SELINUX security_context_t filecon = NULL; #endif if (fstat(fd, &sb) < 0) { virReportSystemError(errno, _("cannot stat file '%s'"), target->path); return -1; } if (allocation) { if (S_ISREG(sb.st_mode)) { #ifndef WIN32 *allocation = (unsigned long long)sb.st_blocks * (unsigned long long)DEV_BSIZE; #else *allocation = sb.st_size; #endif /* Regular files may be sparse, so logical size (capacity) is not same * as actual allocation above */ if (capacity) *capacity = sb.st_size; } else { off_t end; /* XXX this is POSIX compliant, but doesn't work for for CHAR files, * only BLOCK. There is a Linux specific ioctl() for getting * size of both CHAR / BLOCK devices we should check for in * configure */ end = lseek(fd, 0, SEEK_END); if (end == (off_t)-1) { virReportSystemError(errno, _("cannot seek to end of file '%s'"), target->path); return -1; } *allocation = end; if (capacity) *capacity = end; } } target->perms.mode = sb.st_mode & S_IRWXUGO; target->perms.uid = sb.st_uid; target->perms.gid = sb.st_gid; VIR_FREE(target->perms.label); #if HAVE_SELINUX /* XXX: make this a security driver call */ if (fgetfilecon(fd, &filecon) == -1) { if (errno != ENODATA && errno != ENOTSUP) { virReportSystemError(errno, _("cannot get file context of '%s'"), target->path); return -1; } else { target->perms.label = NULL; } } else { target->perms.label = strdup(filecon); if (target->perms.label == NULL) { virReportOOMError(); return -1; } freecon(filecon); } #else target->perms.label = NULL; #endif return 0; } struct diskType { int part_table_type; unsigned short offset; unsigned short length; unsigned long long magic; }; static struct diskType const disk_types[] = { { VIR_STORAGE_POOL_DISK_LVM2, 0x218, 8, 0x31303020324D564CULL }, { VIR_STORAGE_POOL_DISK_GPT, 0x200, 8, 0x5452415020494645ULL }, { VIR_STORAGE_POOL_DISK_DVH, 0x0, 4, 0x41A9E50BULL }, { VIR_STORAGE_POOL_DISK_MAC, 0x0, 2, 0x5245ULL }, { VIR_STORAGE_POOL_DISK_BSD, 0x40, 4, 0x82564557ULL }, { VIR_STORAGE_POOL_DISK_SUN, 0x1fc, 2, 0xBEDAULL }, /* * NOTE: pc98 is funky; the actual signature is 0x55AA (just like dos), so * we can't use that. At the moment I'm relying on the "dummy" IPL * bootloader data that comes from parted. Luckily, the chances of running * into a pc98 machine running libvirt are approximately nil. */ /*{ 0x1fe, 2, 0xAA55UL },*/ { VIR_STORAGE_POOL_DISK_PC98, 0x0, 8, 0x314C5049000000CBULL }, /* * NOTE: the order is important here; some other disk types (like GPT and * and PC98) also have 0x55AA at this offset. For that reason, the DOS * one must be the last one. */ { VIR_STORAGE_POOL_DISK_DOS, 0x1fe, 2, 0xAA55ULL }, { -1, 0x0, 0, 0x0ULL }, }; int virStorageBackendDetectBlockVolFormatFD(virStorageVolTargetPtr target, int fd) { int i; off_t start; unsigned char buffer[1024]; ssize_t bytes; /* make sure to set the target format "unknown" to begin with */ target->format = VIR_STORAGE_POOL_DISK_UNKNOWN; start = lseek(fd, 0, SEEK_SET); if (start < 0) { virReportSystemError(errno, _("cannot seek to beginning of file '%s'"), target->path); return -1; } bytes = saferead(fd, buffer, sizeof(buffer)); if (bytes < 0) { virReportSystemError(errno, _("cannot read beginning of file '%s'"), target->path); return -1; } for (i = 0; disk_types[i].part_table_type != -1; i++) { if (disk_types[i].offset + disk_types[i].length > bytes) continue; if (memcmp(buffer+disk_types[i].offset, &disk_types[i].magic, disk_types[i].length) == 0) { target->format = disk_types[i].part_table_type; break; } } return 0; } /* * Given a volume path directly in /dev/XXX, iterate over the * entries in the directory pool->def->target.path and find the * first symlink pointing to the volume path. * * If, the target.path is /dev/, then return the original volume * path. * * If no symlink is found, then return the original volume path * * Typically target.path is one of the /dev/disk/by-XXX dirs * with stable paths. */ char * virStorageBackendStablePath(virStoragePoolObjPtr pool, const char *devpath) { DIR *dh; struct dirent *dent; char *stablepath; int opentries = 0; /* Short circuit if pool has no target, or if its /dev */ if (pool->def->target.path == NULL || STREQ(pool->def->target.path, "/dev") || STREQ(pool->def->target.path, "/dev/")) goto ret_strdup; /* Skip whole thing for a pool which isn't in /dev * so we don't mess will filesystem/dir based pools */ if (!STRPREFIX(pool->def->target.path, "/dev")) goto ret_strdup; /* We loop here because /dev/disk/by-{id,path} may not have existed * before we started this operation, so we have to give it some time to * get created. */ reopen: if ((dh = opendir(pool->def->target.path)) == NULL) { opentries++; if (errno == ENOENT && opentries < 50) { usleep(100 * 1000); goto reopen; } virReportSystemError(errno, _("cannot read dir '%s'"), pool->def->target.path); return NULL; } /* The pool is pointing somewhere like /dev/disk/by-path * or /dev/disk/by-id, so we need to check all symlinks in * the target directory and figure out which one points * to this device node */ while ((dent = readdir(dh)) != NULL) { if (dent->d_name[0] == '.') continue; if (virAsprintf(&stablepath, "%s/%s", pool->def->target.path, dent->d_name) == -1) { virReportOOMError(); closedir(dh); return NULL; } if (virFileLinkPointsTo(stablepath, devpath)) { closedir(dh); return stablepath; } VIR_FREE(stablepath); } closedir(dh); ret_strdup: /* Couldn't find any matching stable link so give back * the original non-stable dev path */ stablepath = strdup(devpath); if (stablepath == NULL) virReportOOMError(); return stablepath; } #ifndef WIN32 /* * Run an external program. * * Read its output and apply a series of regexes to each line * When the entire set of regexes has matched consecutively * then run a callback passing in all the matches */ int virStorageBackendRunProgRegex(virStoragePoolObjPtr pool, const char *const*prog, int nregex, const char **regex, int *nvars, virStorageBackendListVolRegexFunc func, void *data, int *outexit) { int fd = -1, exitstatus, err, failed = 1; pid_t child = 0; FILE *list = NULL; regex_t *reg; regmatch_t *vars = NULL; char line[1024]; int maxReg = 0, i, j; int totgroups = 0, ngroup = 0, maxvars = 0; char **groups; /* Compile all regular expressions */ if (VIR_ALLOC_N(reg, nregex) < 0) { virReportOOMError(); return -1; } for (i = 0 ; i < nregex ; i++) { err = regcomp(®[i], regex[i], REG_EXTENDED); if (err != 0) { char error[100]; regerror(err, ®[i], error, sizeof(error)); virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("Failed to compile regex %s"), error); for (j = 0 ; j <= i ; j++) regfree(®[j]); VIR_FREE(reg); return -1; } totgroups += nvars[i]; if (nvars[i] > maxvars) maxvars = nvars[i]; } /* Storage for matched variables */ if (VIR_ALLOC_N(groups, totgroups) < 0) { virReportOOMError(); goto cleanup; } if (VIR_ALLOC_N(vars, maxvars+1) < 0) { virReportOOMError(); goto cleanup; } /* Run the program and capture its output */ if (virExec(prog, NULL, NULL, &child, -1, &fd, NULL, VIR_EXEC_NONE) < 0) { goto cleanup; } if ((list = fdopen(fd, "r")) == NULL) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("cannot read fd")); goto cleanup; } while (fgets(line, sizeof(line), list) != NULL) { /* Strip trailing newline */ int len = strlen(line); if (len && line[len-1] == '\n') line[len-1] = '\0'; for (i = 0 ; i <= maxReg && i < nregex ; i++) { if (regexec(®[i], line, nvars[i]+1, vars, 0) == 0) { maxReg++; if (i == 0) ngroup = 0; /* NULL terminate each captured group in the line */ for (j = 0 ; j < nvars[i] ; j++) { /* NB vars[0] is the full pattern, so we offset j by 1 */ line[vars[j+1].rm_eo] = '\0'; if ((groups[ngroup++] = strdup(line + vars[j+1].rm_so)) == NULL) { virReportOOMError(); goto cleanup; } } /* We're matching on the last regex, so callback time */ if (i == (nregex-1)) { if (((*func)(pool, groups, data)) < 0) goto cleanup; /* Release matches & restart to matching the first regex */ for (j = 0 ; j < totgroups ; j++) VIR_FREE(groups[j]); maxReg = 0; ngroup = 0; } } } } failed = 0; cleanup: if (groups) { for (j = 0 ; j < totgroups ; j++) VIR_FREE(groups[j]); VIR_FREE(groups); } VIR_FREE(vars); for (i = 0 ; i < nregex ; i++) regfree(®[i]); VIR_FREE(reg); if (list) fclose(list); else { if (fd >= 0) close(fd); } while ((err = waitpid(child, &exitstatus, 0) == -1) && errno == EINTR); /* Don't bother checking exit status if we already failed */ if (failed) return -1; if (err == -1) { virReportSystemError(errno, _("failed to wait for command '%s'"), prog[0]); return -1; } else { if (WIFEXITED(exitstatus)) { if (outexit != NULL) *outexit = WEXITSTATUS(exitstatus); } else { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("command did not exit cleanly")); return -1; } } return 0; } /* * Run an external program and read from its standard output * a stream of tokens from IN_STREAM, applying FUNC to * each successive sequence of N_COLUMNS tokens. * If FUNC returns < 0, stop processing input and return -1. * Return -1 if N_COLUMNS == 0. * Return -1 upon memory allocation error. * If the number of input tokens is not a multiple of N_COLUMNS, * then the final FUNC call will specify a number smaller than N_COLUMNS. * If there are no input tokens (empty input), call FUNC with N_COLUMNS == 0. */ int virStorageBackendRunProgNul(virStoragePoolObjPtr pool, const char **prog, size_t n_columns, virStorageBackendListVolNulFunc func, void *data) { size_t n_tok = 0; int fd = -1, exitstatus; pid_t child = 0; FILE *fp = NULL; char **v; int err = -1; int w_err; int i; if (n_columns == 0) return -1; if (VIR_ALLOC_N(v, n_columns) < 0) { virReportOOMError(); return -1; } for (i = 0; i < n_columns; i++) v[i] = NULL; /* Run the program and capture its output */ if (virExec(prog, NULL, NULL, &child, -1, &fd, NULL, VIR_EXEC_NONE) < 0) { goto cleanup; } if ((fp = fdopen(fd, "r")) == NULL) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("cannot read fd")); goto cleanup; } while (1) { char *buf = NULL; size_t buf_len = 0; /* Be careful: even when it returns -1, this use of getdelim allocates memory. */ ssize_t tok_len = getdelim (&buf, &buf_len, 0, fp); v[n_tok] = buf; if (tok_len < 0) { /* Maybe EOF, maybe an error. If n_tok > 0, then we know it's an error. */ if (n_tok && func (pool, n_tok, v, data) < 0) goto cleanup; break; } ++n_tok; if (n_tok == n_columns) { if (func (pool, n_tok, v, data) < 0) goto cleanup; n_tok = 0; for (i = 0; i < n_columns; i++) { VIR_FREE(v[i]); } } } if (feof (fp)) err = 0; else virReportSystemError(errno, _("read error on pipe to '%s'"), prog[0]); cleanup: for (i = 0; i < n_columns; i++) VIR_FREE(v[i]); VIR_FREE(v); if (fp) fclose (fp); else close (fd); while ((w_err = waitpid (child, &exitstatus, 0) == -1) && errno == EINTR) /* empty */ ; /* Don't bother checking exit status if we already failed */ if (err < 0) return -1; if (w_err == -1) { virReportSystemError(errno, _("failed to wait for command '%s'"), prog[0]); return -1; } else { if (WIFEXITED(exitstatus)) { if (WEXITSTATUS(exitstatus) != 0) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("non-zero exit status from command %d"), WEXITSTATUS(exitstatus)); return -1; } } else { virStorageReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("command did not exit cleanly")); return -1; } } return 0; } #else /* WIN32 */ int virStorageBackendRunProgRegex(virConnectPtr conn, virStoragePoolObjPtr pool ATTRIBUTE_UNUSED, const char *const*prog ATTRIBUTE_UNUSED, int nregex ATTRIBUTE_UNUSED, const char **regex ATTRIBUTE_UNUSED, int *nvars ATTRIBUTE_UNUSED, virStorageBackendListVolRegexFunc func ATTRIBUTE_UNUSED, void *data ATTRIBUTE_UNUSED, int *outexit ATTRIBUTE_UNUSED) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("%s not implemented on Win32"), __FUNCTION__); return -1; } int virStorageBackendRunProgNul(virConnectPtr conn, virStoragePoolObjPtr pool ATTRIBUTE_UNUSED, const char **prog ATTRIBUTE_UNUSED, size_t n_columns ATTRIBUTE_UNUSED, virStorageBackendListVolNulFunc func ATTRIBUTE_UNUSED, void *data ATTRIBUTE_UNUSED) { virStorageReportError(VIR_ERR_INTERNAL_ERROR, _("%s not implemented on Win32"), __FUNCTION__); return -1; } #endif /* WIN32 */