[libvirt] [PATCH v2 3/5] storage: vstorage pool operations
Olga Krishtal
okrishtal at virtuozzo.com
Tue Jan 17 14:10:57 UTC 2017
Added create/define/etc pool operations for vstorage backend.
The vstorage storage pool looks like netfs ones. Due to this
some of pool/volume functions were taken with no changes:
refresh pool function.
Signed-off-by: Olga Krishtal <okrishtal at virtuozzo.com>
---
src/storage/storage_backend_vstorage.c | 530 +++++++++++++++++++++++++++++++++
1 file changed, 530 insertions(+)
diff --git a/src/storage/storage_backend_vstorage.c b/src/storage/storage_backend_vstorage.c
index 3a57385..8332f4d 100644
--- a/src/storage/storage_backend_vstorage.c
+++ b/src/storage/storage_backend_vstorage.c
@@ -6,11 +6,541 @@
#include "storage_backend_vstorage.h"
#include "virlog.h"
#include "virstring.h"
+#include <mntent.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/statvfs.h>
+#include <sys/stat.h>
+#include <fcntl.h>
#define VIR_FROM_THIS VIR_FROM_STORAGE
+#define VIR_STORAGE_VOL_FS_OPEN_FLAGS (VIR_STORAGE_VOL_OPEN_DEFAULT | \
+ VIR_STORAGE_VOL_OPEN_DIR)
+#define VIR_STORAGE_VOL_FS_PROBE_FLAGS (VIR_STORAGE_VOL_FS_OPEN_FLAGS | \
+ VIR_STORAGE_VOL_OPEN_NOERROR)
+
+
+
VIR_LOG_INIT("storage.storage_backend_vstorage");
+/**
+ * @conn connection to report errors against
+ * @pool storage pool to build
+ * @flags controls the pool formatting behaviour
+ *
+ *
+ * If no flag is set, it only makes the directory;
+ * If VIR_STORAGE_POOL_BUILD_NO_OVERWRITE set, it determines if
+ * the directory exists and if yes - we use it. Otherwise - the new one
+ * will be created.
+ * If VIR_STORAGE_POOL_BUILD_OVERWRITE is set, the dircetory for pool
+ * will used but the content and permissions will be updated
+ *
+ * Returns 0 on success, -1 on error
+ */
+
+static int
+virStorageBackendVzPoolBuild(virConnectPtr conn ATTRIBUTE_UNUSED,
+ virStoragePoolObjPtr pool,
+ unsigned int flags)
+{
+ int ret = -1;
+ char *parent = NULL;
+ char *p = NULL;
+ mode_t mode;
+ unsigned int dir_create_flags;
+
+ virCheckFlags(VIR_STORAGE_POOL_BUILD_OVERWRITE |
+ VIR_STORAGE_POOL_BUILD_NO_OVERWRITE, ret);
+
+ VIR_EXCLUSIVE_FLAGS_GOTO(VIR_STORAGE_POOL_BUILD_OVERWRITE,
+ VIR_STORAGE_POOL_BUILD_NO_OVERWRITE,
+ error);
+
+ if (VIR_STRDUP(parent, pool->def->target.path) < 0)
+ goto error;
+ if (!(p = strrchr(parent, '/'))) {
+ virReportError(VIR_ERR_INVALID_ARG,
+ _("path '%s' is not absolute"),
+ pool->def->target.path);
+ goto error;
+ }
+
+ if (p != parent) {
+ /* assure all directories in the path prior to the final dir
+ * exist, with default uid/gid/mode. */
+ *p = '\0';
+ if (virFileMakePath(parent) < 0) {
+ virReportSystemError(errno, _("cannot create path '%s'"),
+ parent);
+ goto error;
+ }
+ }
+
+ dir_create_flags = VIR_DIR_CREATE_ALLOW_EXIST;
+ mode = pool->def->target.perms.mode;
+
+ if (mode == (mode_t) -1 && !virFileExists(pool->def->target.path))
+ mode = VIR_STORAGE_DEFAULT_POOL_PERM_MODE;
+
+ /* Now create the final dir in the path with the uid/gid/mode
+ * requested in the config. If the dir already exists, just set
+ * the perms. */
+ if (virDirCreate(pool->def->target.path,
+ mode,
+ pool->def->target.perms.uid,
+ pool->def->target.perms.gid,
+ dir_create_flags) < 0)
+ goto error;
+
+ /* Delete directory content if flag is set*/
+ if (flags & VIR_STORAGE_POOL_BUILD_OVERWRITE)
+ if (virFileDeleteTree(pool->def->target.path))
+ goto error;
+
+ ret = 0;
+
+ error:
+ VIR_FREE(parent);
+ return ret;
+}
+
+static int
+virStorageBackendVzPoolStart(virConnectPtr conn ATTRIBUTE_UNUSED,
+ virStoragePoolObjPtr pool)
+{
+ int ret = -1;
+ virCommandPtr cmd = NULL;
+ char *grp_name = NULL;
+ char *usr_name = NULL;
+ char *mode = NULL;
+
+ /* Check the permissions */
+ if (pool->def->target.perms.mode == (mode_t) - 1)
+ pool->def->target.perms.mode = VIR_STORAGE_DEFAULT_POOL_PERM_MODE;
+ if (pool->def->target.perms.uid == (uid_t) -1)
+ pool->def->target.perms.uid = geteuid();
+ if (pool->def->target.perms.gid == (gid_t) -1)
+ pool->def->target.perms.gid = getegid();
+
+ /* Convert ids to names because vstorage uses names */
+
+ grp_name = virGetGroupName(pool->def->target.perms.gid);
+ if (!grp_name)
+ return -1;
+
+ usr_name = virGetUserName(pool->def->target.perms.uid);
+ if (!usr_name)
+ return -1;
+
+ if (virAsprintf(&mode, "%o", pool->def->target.perms.mode) < 0)
+ return -1;
+
+ cmd = virCommandNewArgList(VSTORAGE_MOUNT,
+ "-c", pool->def->source.name,
+ pool->def->target.path,
+ "-m", mode,
+ "-g", grp_name, "-u", usr_name,
+ NULL);
+
+ if (virCommandRun(cmd, NULL) < 0)
+ goto cleanup;
+ ret = 0;
+
+ cleanup:
+ virCommandFree(cmd);
+ VIR_FREE(mode);
+ VIR_FREE(grp_name);
+ VIR_FREE(usr_name);
+ return ret;
+}
+
+static int
+virStorageBackendVzIsMounted(virStoragePoolObjPtr pool)
+{
+ int ret = -1;
+ char *src = NULL;
+ FILE *mtab;
+ struct mntent ent;
+ char buf[1024];
+ char *cluster = NULL;
+
+ if (virAsprintf(&cluster, "vstorage://%s", pool->def->source.name) < 0)
+ return -1;
+
+ if ((mtab = fopen(_PATH_MOUNTED, "r")) == NULL) {
+ virReportSystemError(errno,
+ _("cannot read mount list '%s'"),
+ _PATH_MOUNTED);
+ goto cleanup;
+ }
+
+ while ((getmntent_r(mtab, &ent, buf, sizeof(buf))) != NULL) {
+
+ if (STREQ(ent.mnt_dir, pool->def->target.path) &&
+ STREQ(ent.mnt_fsname, cluster)) {
+ ret = 1;
+ goto cleanup;
+ }
+
+ VIR_FREE(src);
+ }
+
+ ret = 0;
+
+ cleanup:
+ VIR_FORCE_FCLOSE(mtab);
+ VIR_FREE(src);
+ VIR_FREE(cluster);
+ return ret;
+}
+
+static int
+virStorageBackendVzUmount(virStoragePoolObjPtr pool)
+{
+ virCommandPtr cmd = NULL;
+ int ret = -1;
+ int rc;
+
+ /* Short-circuit if already unmounted */
+ if ((rc = virStorageBackendVzIsMounted(pool)) != 1)
+ return rc;
+
+ cmd = virCommandNewArgList(UMOUNT,
+ pool->def->target.path,
+ NULL);
+
+ if (virCommandRun(cmd, NULL) < 0)
+ goto cleanup;
+
+ ret = 0;
+ cleanup:
+ virCommandFree(cmd);
+ return ret;
+}
+
+static int
+virStorageBackendVzPoolStop(virConnectPtr conn ATTRIBUTE_UNUSED,
+ virStoragePoolObjPtr pool)
+{
+ if (virStorageBackendVzUmount(pool) < 0)
+ return -1;
+
+ return 0;
+}
+
+/**
+ * @conn connection to report errors against
+ * @pool storage pool to delete
+ *
+ * Deletes vstorage based storage pool.
+ * At this moment vstorage is in umounted state - so we do not
+ * need to delete volumes first.
+ * Returns 0 on success, -1 on error
+ */
+static int
+virStorageBackendVzDelete(virConnectPtr conn ATTRIBUTE_UNUSED,
+ virStoragePoolObjPtr pool,
+ unsigned int flags)
+{
+ virCheckFlags(0, -1);
+
+ if (rmdir(pool->def->target.path) < 0) {
+ virReportSystemError(errno,
+ _("failed to remove pool '%s'"),
+ pool->def->target.path);
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Check wether the cluster is mounted
+ */
+static int
+virStorageBackendVzCheck(virStoragePoolObjPtr pool,
+ bool *isActive)
+{
+ int ret = -1;
+ *isActive = false;
+ if ((ret = virStorageBackendVzIsMounted(pool)) != 0) {
+ if (ret < 0)
+ return -1;
+ *isActive = true;
+ }
+
+ return 0;
+}
+
+/* All the underlying functions were directly copied from
+ * filesystem backend with no changes.
+ */
+
+static int
+virStorageBackendProbeTarget(virStorageSourcePtr target,
+ virStorageEncryptionPtr *encryption)
+{
+ int backingStoreFormat;
+ int fd = -1;
+ int ret = -1;
+ int rc;
+ virStorageSourcePtr meta = NULL;
+ struct stat sb;
+
+ if (encryption)
+ *encryption = NULL;
+
+ if ((rc = virStorageBackendVolOpen(target->path, &sb,
+ VIR_STORAGE_VOL_FS_PROBE_FLAGS)) < 0)
+ return rc; /* Take care to propagate rc, it is not always -1 */
+ fd = rc;
+
+ if (virStorageBackendUpdateVolTargetInfoFD(target, fd, &sb) < 0)
+ goto cleanup;
+
+ if (S_ISDIR(sb.st_mode)) {
+ if (virStorageBackendIsPloopDir(target->path)) {
+ if (virStorageBackendRedoPloopUpdate(target, &sb, &fd,
+ VIR_STORAGE_VOL_FS_PROBE_FLAGS) < 0)
+ goto cleanup;
+ } else {
+ target->format = VIR_STORAGE_FILE_DIR;
+ ret = 0;
+ goto cleanup;
+ }
+ }
+
+ if (!(meta = virStorageFileGetMetadataFromFD(target->path,
+ fd,
+ VIR_STORAGE_FILE_AUTO,
+ &backingStoreFormat)))
+ goto cleanup;
+
+ if (meta->backingStoreRaw) {
+ if (!(target->backingStore = virStorageSourceNewFromBacking(meta)))
+ goto cleanup;
+
+ target->backingStore->format = backingStoreFormat;
+
+ /* XXX: Remote storage doesn't play nicely with volumes backed by
+ * remote storage. To avoid trouble, just fake the backing store is RAW
+ * and put the string from the metadata as the path of the target. */
+ if (!virStorageSourceIsLocalStorage(target->backingStore)) {
+ virStorageSourceFree(target->backingStore);
+
+ if (VIR_ALLOC(target->backingStore) < 0)
+ goto cleanup;
+
+ target->backingStore->type = VIR_STORAGE_TYPE_NETWORK;
+ target->backingStore->path = meta->backingStoreRaw;
+ meta->backingStoreRaw = NULL;
+ target->backingStore->format = VIR_STORAGE_FILE_RAW;
+ }
+
+ if (target->backingStore->format == VIR_STORAGE_FILE_AUTO) {
+ if ((rc = virStorageFileProbeFormat(target->backingStore->path,
+ -1, -1)) < 0) {
+ /* If the backing file is currently unavailable or is
+ * accessed via remote protocol only log an error, fake the
+ * format as RAW and continue. Returning -1 here would
+ * disable the whole storage pool, making it unavailable for
+ * even maintenance. */
+ target->backingStore->format = VIR_STORAGE_FILE_RAW;
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("cannot probe backing volume format: %s"),
+ target->backingStore->path);
+ } else {
+ target->backingStore->format = rc;
+ }
+ }
+ }
+
+ target->format = meta->format;
+
+ /* Default to success below this point */
+ ret = 0;
+
+ if (meta->capacity)
+ target->capacity = meta->capacity;
+
+ if (encryption && meta->encryption) {
+ *encryption = meta->encryption;
+ meta->encryption = NULL;
+
+ /* XXX ideally we'd fill in secret UUID here
+ * but we cannot guarantee 'conn' is non-NULL
+ * at this point in time :-( So we only fill
+ * in secrets when someone first queries a vol
+ */
+ }
+
+ virBitmapFree(target->features);
+ target->features = meta->features;
+ meta->features = NULL;
+
+ if (meta->compat) {
+ VIR_FREE(target->compat);
+ target->compat = meta->compat;
+ meta->compat = NULL;
+ }
+
+ cleanup:
+ VIR_FORCE_CLOSE(fd);
+ virStorageSourceFree(meta);
+ return ret;
+
+}
+
+/**
+ * The same as for fs/dir storage pools
+ * Iterate over the pool's directory and enumerate all disk images
+ * within it. This is non-recursive.
+ */
+
+static int
+virStorageBackendVzRefresh(virConnectPtr conn ATTRIBUTE_UNUSED,
+ virStoragePoolObjPtr pool)
+{
+ DIR *dir;
+ struct dirent *ent;
+ struct statvfs sb;
+ struct stat statbuf;
+ virStorageVolDefPtr vol = NULL;
+ virStorageSourcePtr target = NULL;
+ int direrr;
+ int fd = -1, ret = -1;
+
+ if (virDirOpen(&dir, pool->def->target.path) < 0)
+ goto cleanup;
+
+ while ((direrr = virDirRead(dir, &ent, pool->def->target.path)) > 0) {
+ int err;
+
+ if (virStringHasControlChars(ent->d_name)) {
+ VIR_WARN("Ignoring file with control characters under '%s'",
+ pool->def->target.path);
+ continue;
+ }
+
+ if (VIR_ALLOC(vol) < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(vol->name, ent->d_name) < 0)
+ goto cleanup;
+
+ vol->type = VIR_STORAGE_VOL_FILE;
+ vol->target.format = VIR_STORAGE_FILE_RAW; /* Real value is filled in during probe */
+ if (virAsprintf(&vol->target.path, "%s/%s",
+ pool->def->target.path,
+ vol->name) == -1)
+ goto cleanup;
+
+ if (VIR_STRDUP(vol->key, vol->target.path) < 0)
+ goto cleanup;
+
+ if ((err = virStorageBackendProbeTarget(&vol->target,
+ &vol->target.encryption)) < 0) {
+ if (err == -2) {
+ /* Silently ignore non-regular files,
+ * eg 'lost+found', dangling symbolic link */
+ virStorageVolDefFree(vol);
+ vol = NULL;
+ continue;
+ } else if (err == -3) {
+ /* The backing file is currently unavailable, its format is not
+ * explicitly specified, the probe to auto detect the format
+ * failed: continue with faked RAW format, since AUTO will
+ * break virStorageVolTargetDefFormat() generating the line
+ * <format type='...'/>. */
+ } else {
+ goto cleanup;
+ }
+ }
+
+ /* directory based volume */
+ if (vol->target.format == VIR_STORAGE_FILE_DIR)
+ vol->type = VIR_STORAGE_VOL_DIR;
+
+ if (vol->target.format == VIR_STORAGE_FILE_PLOOP)
+ vol->type = VIR_STORAGE_VOL_PLOOP;
+
+ if (vol->target.backingStore) {
+ ignore_value(virStorageBackendUpdateVolTargetInfo(vol->target.backingStore,
+ false,
+ VIR_STORAGE_VOL_OPEN_DEFAULT, 0));
+ /* If this failed, the backing file is currently unavailable,
+ * the capacity, allocation, owner, group and mode are unknown.
+ * An error message was raised, but we just continue. */
+ }
+
+ if (VIR_APPEND_ELEMENT(pool->volumes.objs, pool->volumes.count, vol) < 0)
+ goto cleanup;
+ }
+ if (direrr < 0)
+ goto cleanup;
+ VIR_DIR_CLOSE(dir);
+ vol = NULL;
+
+ if (VIR_ALLOC(target))
+ goto cleanup;
+
+ if ((fd = open(pool->def->target.path, O_RDONLY)) < 0) {
+ virReportSystemError(errno,
+ _("cannot open path '%s'"),
+ pool->def->target.path);
+ goto cleanup;
+ }
+
+ if (fstat(fd, &statbuf) < 0) {
+ virReportSystemError(errno,
+ _("cannot stat path '%s'"),
+ pool->def->target.path);
+ goto cleanup;
+ }
+
+ if (virStorageBackendUpdateVolTargetInfoFD(target, fd, &statbuf) < 0)
+ goto cleanup;
+
+ /* VolTargetInfoFD doesn't update capacity correctly for the pool case */
+ if (statvfs(pool->def->target.path, &sb) < 0) {
+ virReportSystemError(errno,
+ _("cannot statvfs path '%s'"),
+ pool->def->target.path);
+ goto cleanup;
+ }
+
+ pool->def->capacity = ((unsigned long long)sb.f_frsize *
+ (unsigned long long)sb.f_blocks);
+ pool->def->available = ((unsigned long long)sb.f_bfree *
+ (unsigned long long)sb.f_frsize);
+ pool->def->allocation = pool->def->capacity - pool->def->available;
+
+ pool->def->target.perms.mode = target->perms->mode;
+ pool->def->target.perms.uid = target->perms->uid;
+ pool->def->target.perms.gid = target->perms->gid;
+ VIR_FREE(pool->def->target.perms.label);
+ if (VIR_STRDUP(pool->def->target.perms.label, target->perms->label) < 0)
+ goto cleanup;
+
+ ret = 0;
+ cleanup:
+ VIR_DIR_CLOSE(dir);
+ VIR_FORCE_CLOSE(fd);
+ virStorageVolDefFree(vol);
+ virStorageSourceFree(target);
+ if (ret < 0)
+ virStoragePoolObjClearVols(pool);
+ return ret;
+}
virStorageBackend virStorageBackendVstorage = {
.type = VIR_STORAGE_POOL_VSTORAGE,
+
+ .buildPool = virStorageBackendVzPoolBuild,
+ .startPool = virStorageBackendVzPoolStart,
+ .stopPool = virStorageBackendVzPoolStop,
+ .deletePool = virStorageBackendVzDelete,
+ .refreshPool = virStorageBackendVzRefresh,
+ .checkPool = virStorageBackendVzCheck,
};
--
1.8.3.1
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