X-Git-Url: https://code.grnet.gr/git/ganeti-local/blobdiff_plain/94dcbdb031f1d8a8bcd368ed911e83a25eabb1c2..432e8e2f3a21139d6e1bb39b4a38448e2af0f902:/lib/bdev.py?ds=sidebyside diff --git a/lib/bdev.py b/lib/bdev.py index b9fc651..05a0ea1 100644 --- a/lib/bdev.py +++ b/lib/bdev.py @@ -24,6 +24,7 @@ import re import time import errno +import shlex import stat import pyparsing as pyp import os @@ -220,16 +221,22 @@ class BlockDev(object): """ raise NotImplementedError - def SetSyncSpeed(self, speed): - """Adjust the sync speed of the mirror. + def SetSyncParams(self, params): + """Adjust the synchronization parameters of the mirror. In case this is not a mirroring device, this is no-op. + @param params: dictionary of LD level disk parameters related to the + synchronization. + @rtype: list + @return: a list of error messages, emitted both by the current node and by + children. An empty list means no errors. + """ - result = True + result = [] if self._children: for child in self._children: - result = result and child.SetSyncSpeed(speed) + result.extend(child.SetSyncParams(params)) return result def PauseResumeSync(self, pause): @@ -237,7 +244,7 @@ class BlockDev(object): In case this is not a mirroring device, this is no-op. - @param pause: Wheater to pause or resume + @param pause: Whether to pause or resume """ result = True @@ -415,7 +422,11 @@ class LogicalVolume(BlockDev): " in lvm.conf using either 'filter' or 'preferred_names'") free_size = sum([pv[0] for pv in pvs_info]) current_pvs = len(pvlist) - stripes = min(current_pvs, constants.LVM_STRIPECOUNT) + desired_stripes = params[constants.LDP_STRIPES] + stripes = min(current_pvs, desired_stripes) + if stripes < desired_stripes: + logging.warning("Could not use %d stripes for VG %s, as only %d PVs are" + " available.", desired_stripes, vg_name, current_pvs) # The size constraint should have been checked from the master before # calling the create function. @@ -1099,6 +1110,12 @@ class DRBD8(BaseDRBD): # timeout constants _NET_RECONFIG_TIMEOUT = 60 + # command line options for barriers + _DISABLE_DISK_OPTION = "--no-disk-barrier" # -a + _DISABLE_DRAIN_OPTION = "--no-disk-drain" # -D + _DISABLE_FLUSH_OPTION = "--no-disk-flushes" # -i + _DISABLE_META_FLUSH_OPTION = "--no-md-flushes" # -m + def __init__(self, unique_id, children, size, params): if children and children.count(None) > 0: children = [] @@ -1340,41 +1357,110 @@ class DRBD8(BaseDRBD): info["remote_addr"] == (self._rhost, self._rport)) return retval - @classmethod - def _AssembleLocal(cls, minor, backend, meta, size): + def _AssembleLocal(self, minor, backend, meta, size): """Configure the local part of a DRBD device. """ - args = ["drbdsetup", cls._DevPath(minor), "disk", + args = ["drbdsetup", self._DevPath(minor), "disk", backend, meta, "0", "-e", "detach", "--create-device"] if size: args.extend(["-d", "%sm" % size]) - if not constants.DRBD_BARRIERS: # disable barriers, if configured so - version = cls._GetVersion(cls._GetProcData()) - # various DRBD versions support different disk barrier options; - # what we aim here is to revert back to the 'drain' method of - # disk flushes and to disable metadata barriers, in effect going - # back to pre-8.0.7 behaviour - vmaj = version["k_major"] - vmin = version["k_minor"] - vrel = version["k_point"] - assert vmaj == 8 - if vmin == 0: # 8.0.x - if vrel >= 12: - args.extend(["-i", "-m"]) - elif vmin == 2: # 8.2.x - if vrel >= 7: - args.extend(["-i", "-m"]) - elif vmaj >= 3: # 8.3.x or newer - args.extend(["-i", "-a", "m"]) + + version = self._GetVersion(self._GetProcData()) + vmaj = version["k_major"] + vmin = version["k_minor"] + vrel = version["k_point"] + + barrier_args = \ + self._ComputeDiskBarrierArgs(vmaj, vmin, vrel, + self.params[constants.LDP_BARRIERS], + self.params[constants.LDP_NO_META_FLUSH]) + args.extend(barrier_args) + + if self.params[constants.LDP_DISK_CUSTOM]: + args.extend(shlex.split(self.params[constants.LDP_DISK_CUSTOM])) + result = utils.RunCmd(args) if result.failed: _ThrowError("drbd%d: can't attach local disk: %s", minor, result.output) @classmethod - def _AssembleNet(cls, minor, net_info, protocol, + def _ComputeDiskBarrierArgs(cls, vmaj, vmin, vrel, disabled_barriers, + disable_meta_flush): + """Compute the DRBD command line parameters for disk barriers + + Returns a list of the disk barrier parameters as requested via the + disabled_barriers and disable_meta_flush arguments, and according to the + supported ones in the DRBD version vmaj.vmin.vrel + + If the desired option is unsupported, raises errors.BlockDeviceError. + + """ + disabled_barriers_set = frozenset(disabled_barriers) + if not disabled_barriers_set in constants.DRBD_VALID_BARRIER_OPT: + raise errors.BlockDeviceError("%s is not a valid option set for DRBD" + " barriers" % disabled_barriers) + + args = [] + + # The following code assumes DRBD 8.x, with x < 4 and x != 1 (DRBD 8.1.x + # does not exist) + if not vmaj == 8 and vmin in (0, 2, 3): + raise errors.BlockDeviceError("Unsupported DRBD version: %d.%d.%d" % + (vmaj, vmin, vrel)) + + def _AppendOrRaise(option, min_version): + """Helper for DRBD options""" + if min_version is not None and vrel >= min_version: + args.append(option) + else: + raise errors.BlockDeviceError("Could not use the option %s as the" + " DRBD version %d.%d.%d does not support" + " it." % (option, vmaj, vmin, vrel)) + + # the minimum version for each feature is encoded via pairs of (minor + # version -> x) where x is version in which support for the option was + # introduced. + meta_flush_supported = disk_flush_supported = { + 0: 12, + 2: 7, + 3: 0, + } + + disk_drain_supported = { + 2: 7, + 3: 0, + } + + disk_barriers_supported = { + 3: 0, + } + + # meta flushes + if disable_meta_flush: + _AppendOrRaise(cls._DISABLE_META_FLUSH_OPTION, + meta_flush_supported.get(vmin, None)) + + # disk flushes + if constants.DRBD_B_DISK_FLUSH in disabled_barriers_set: + _AppendOrRaise(cls._DISABLE_FLUSH_OPTION, + disk_flush_supported.get(vmin, None)) + + # disk drain + if constants.DRBD_B_DISK_DRAIN in disabled_barriers_set: + _AppendOrRaise(cls._DISABLE_DRAIN_OPTION, + disk_drain_supported.get(vmin, None)) + + # disk barriers + if constants.DRBD_B_DISK_BARRIERS in disabled_barriers_set: + _AppendOrRaise(cls._DISABLE_DISK_OPTION, + disk_barriers_supported.get(vmin, None)) + + return args + + def _AssembleNet(self, minor, net_info, protocol, dual_pri=False, hmac=None, secret=None): """Configure the network part of the device. @@ -1383,7 +1469,7 @@ class DRBD8(BaseDRBD): if None in net_info: # we don't want network connection and actually want to make # sure its shutdown - cls._ShutdownNet(minor) + self._ShutdownNet(minor) return # Workaround for a race condition. When DRBD is doing its dance to @@ -1392,7 +1478,10 @@ class DRBD8(BaseDRBD): # sync speed only after setting up both sides can race with DRBD # connecting, hence we set it here before telling DRBD anything # about its peer. - cls._SetMinorSyncSpeed(minor, constants.SYNC_SPEED) + sync_errors = self._SetMinorSyncParams(minor, self.params) + if sync_errors: + _ThrowError("drbd%d: can't set the synchronization parameters: %s" % + (minor, utils.CommaJoin(sync_errors))) if netutils.IP6Address.IsValid(lhost): if not netutils.IP6Address.IsValid(rhost): @@ -1407,7 +1496,7 @@ class DRBD8(BaseDRBD): else: _ThrowError("drbd%d: Invalid ip %s" % (minor, lhost)) - args = ["drbdsetup", cls._DevPath(minor), "net", + args = ["drbdsetup", self._DevPath(minor), "net", "%s:%s:%s" % (family, lhost, lport), "%s:%s:%s" % (family, rhost, rport), protocol, "-A", "discard-zero-changes", @@ -1418,13 +1507,17 @@ class DRBD8(BaseDRBD): args.append("-m") if hmac and secret: args.extend(["-a", hmac, "-x", secret]) + + if self.params[constants.LDP_NET_CUSTOM]: + args.extend(shlex.split(self.params[constants.LDP_NET_CUSTOM])) + result = utils.RunCmd(args) if result.failed: _ThrowError("drbd%d: can't setup network: %s - %s", minor, result.fail_reason, result.output) def _CheckNetworkConfig(): - info = cls._GetDevInfo(cls._GetShowData(minor)) + info = self._GetDevInfo(self._GetShowData(minor)) if not "local_addr" in info or not "remote_addr" in info: raise utils.RetryAgain() @@ -1488,40 +1581,80 @@ class DRBD8(BaseDRBD): self._children = [] @classmethod - def _SetMinorSyncSpeed(cls, minor, kbytes): - """Set the speed of the DRBD syncer. + def _SetMinorSyncParams(cls, minor, params): + """Set the parameters of the DRBD syncer. This is the low-level implementation. @type minor: int @param minor: the drbd minor whose settings we change - @type kbytes: int - @param kbytes: the speed in kbytes/second - @rtype: boolean - @return: the success of the operation + @type params: dict + @param params: LD level disk parameters related to the synchronization + @rtype: list + @return: a list of error messages """ - result = utils.RunCmd(["drbdsetup", cls._DevPath(minor), "syncer", - "-r", "%d" % kbytes, "--create-device"]) + + args = ["drbdsetup", cls._DevPath(minor), "syncer"] + if params[constants.LDP_DYNAMIC_RESYNC]: + version = cls._GetVersion(cls._GetProcData()) + vmin = version["k_minor"] + vrel = version["k_point"] + + # By definition we are using 8.x, so just check the rest of the version + # number + if vmin != 3 or vrel < 9: + msg = ("The current DRBD version (8.%d.%d) does not support the " + "dynamic resync speed controller" % (vmin, vrel)) + logging.error(msg) + return [msg] + + if params[constants.LDP_PLAN_AHEAD] == 0: + msg = ("A value of 0 for c-plan-ahead disables the dynamic sync speed" + " controller at DRBD level. If you want to disable it, please" + " set the dynamic-resync disk parameter to False.") + logging.error(msg) + return [msg] + + # add the c-* parameters to args + args.extend(["--c-plan-ahead", params[constants.LDP_PLAN_AHEAD], + "--c-fill-target", params[constants.LDP_FILL_TARGET], + "--c-delay-target", params[constants.LDP_DELAY_TARGET], + "--c-max-rate", params[constants.LDP_MAX_RATE], + "--c-min-rate", params[constants.LDP_MIN_RATE], + ]) + + else: + args.extend(["-r", "%d" % params[constants.LDP_RESYNC_RATE]]) + + args.append("--create-device") + result = utils.RunCmd(args) if result.failed: - logging.error("Can't change syncer rate: %s - %s", - result.fail_reason, result.output) - return not result.failed + msg = ("Can't change syncer rate: %s - %s" % + (result.fail_reason, result.output)) + logging.error(msg) + return msg - def SetSyncSpeed(self, kbytes): - """Set the speed of the DRBD syncer. + return [] - @type kbytes: int - @param kbytes: the speed in kbytes/second - @rtype: boolean - @return: the success of the operation + def SetSyncParams(self, params): + """Set the synchronization parameters of the DRBD syncer. + + @type params: dict + @param params: LD level disk parameters related to the synchronization + @rtype: list + @return: a list of error messages, emitted both by the current node and by + children. An empty list means no errors """ if self.minor is None: - logging.info("Not attached during SetSyncSpeed") - return False - children_result = super(DRBD8, self).SetSyncSpeed(kbytes) - return self._SetMinorSyncSpeed(self.minor, kbytes) and children_result + err = "Not attached during SetSyncParams" + logging.info(err) + return [err] + + children_result = super(DRBD8, self).SetSyncParams(params) + children_result.extend(self._SetMinorSyncParams(self.minor, params)) + return children_result def PauseResumeSync(self, pause): """Pauses or resumes the sync of a DRBD device. @@ -1758,7 +1891,10 @@ class DRBD8(BaseDRBD): # the device self._SlowAssemble() - self.SetSyncSpeed(constants.SYNC_SPEED) + sync_errors = self.SetSyncParams(self.params) + if sync_errors: + _ThrowError("drbd%d: can't set the synchronization parameters: %s" % + (self.minor, utils.CommaJoin(sync_errors))) def _SlowAssemble(self): """Assembles the DRBD device from a (partially) configured device. @@ -2210,10 +2346,302 @@ class PersistentBlockDevice(BlockDev): _ThrowError("Grow is not supported for PersistentBlockDev storage") +class RADOSBlockDevice(BlockDev): + """A RADOS Block Device (rbd). + + This class implements the RADOS Block Device for the backend. You need + the rbd kernel driver, the RADOS Tools and a working RADOS cluster for + this to be functional. + + """ + def __init__(self, unique_id, children, size, params): + """Attaches to an rbd device. + + """ + super(RADOSBlockDevice, self).__init__(unique_id, children, size, params) + if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: + raise ValueError("Invalid configuration data %s" % str(unique_id)) + + self.driver, self.rbd_name = unique_id + + self.major = self.minor = None + self.Attach() + + @classmethod + def Create(cls, unique_id, children, size, params): + """Create a new rbd device. + + Provision a new rbd volume inside a RADOS pool. + + """ + if not isinstance(unique_id, (tuple, list)) or len(unique_id) != 2: + raise errors.ProgrammerError("Invalid configuration data %s" % + str(unique_id)) + rbd_pool = params[constants.LDP_POOL] + rbd_name = unique_id[1] + + # Provision a new rbd volume (Image) inside the RADOS cluster. + cmd = [constants.RBD_CMD, "create", "-p", rbd_pool, + rbd_name, "--size", "%s" % size] + result = utils.RunCmd(cmd) + if result.failed: + _ThrowError("rbd creation failed (%s): %s", + result.fail_reason, result.output) + + return RADOSBlockDevice(unique_id, children, size, params) + + def Remove(self): + """Remove the rbd device. + + """ + rbd_pool = self.params[constants.LDP_POOL] + rbd_name = self.unique_id[1] + + if not self.minor and not self.Attach(): + # The rbd device doesn't exist. + return + + # First shutdown the device (remove mappings). + self.Shutdown() + + # Remove the actual Volume (Image) from the RADOS cluster. + cmd = [constants.RBD_CMD, "rm", "-p", rbd_pool, rbd_name] + result = utils.RunCmd(cmd) + if result.failed: + _ThrowError("Can't remove Volume from cluster with rbd rm: %s - %s", + result.fail_reason, result.output) + + def Rename(self, new_id): + """Rename this device. + + """ + pass + + def Attach(self): + """Attach to an existing rbd device. + + This method maps the rbd volume that matches our name with + an rbd device and then attaches to this device. + + """ + self.attached = False + + # Map the rbd volume to a block device under /dev + self.dev_path = self._MapVolumeToBlockdev(self.unique_id) + + try: + st = os.stat(self.dev_path) + except OSError, err: + logging.error("Error stat()'ing %s: %s", self.dev_path, str(err)) + return False + + if not stat.S_ISBLK(st.st_mode): + logging.error("%s is not a block device", self.dev_path) + return False + + self.major = os.major(st.st_rdev) + self.minor = os.minor(st.st_rdev) + self.attached = True + + return True + + def _MapVolumeToBlockdev(self, unique_id): + """Maps existing rbd volumes to block devices. + + This method should be idempotent if the mapping already exists. + + @rtype: string + @return: the block device path that corresponds to the volume + + """ + pool = self.params[constants.LDP_POOL] + name = unique_id[1] + + # Check if the mapping already exists. + showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool] + result = utils.RunCmd(showmap_cmd) + if result.failed: + _ThrowError("rbd showmapped failed (%s): %s", + result.fail_reason, result.output) + + rbd_dev = self._ParseRbdShowmappedOutput(result.output, name) + + if rbd_dev: + # The mapping exists. Return it. + return rbd_dev + + # The mapping doesn't exist. Create it. + map_cmd = [constants.RBD_CMD, "map", "-p", pool, name] + result = utils.RunCmd(map_cmd) + if result.failed: + _ThrowError("rbd map failed (%s): %s", + result.fail_reason, result.output) + + # Find the corresponding rbd device. + showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool] + result = utils.RunCmd(showmap_cmd) + if result.failed: + _ThrowError("rbd map succeeded, but showmapped failed (%s): %s", + result.fail_reason, result.output) + + rbd_dev = self._ParseRbdShowmappedOutput(result.output, name) + + if not rbd_dev: + _ThrowError("rbd map succeeded, but could not find the rbd block" + " device in output of showmapped, for volume: %s", name) + + # The device was successfully mapped. Return it. + return rbd_dev + + @staticmethod + def _ParseRbdShowmappedOutput(output, volume_name): + """Parse the output of `rbd showmapped'. + + This method parses the output of `rbd showmapped' and returns + the rbd block device path (e.g. /dev/rbd0) that matches the + given rbd volume. + + @type output: string + @param output: the whole output of `rbd showmapped' + @type volume_name: string + @param volume_name: the name of the volume whose device we search for + @rtype: string or None + @return: block device path if the volume is mapped, else None + + """ + allfields = 5 + volumefield = 2 + devicefield = 4 + + field_sep = "\t" + + lines = output.splitlines() + splitted_lines = map(lambda l: l.split(field_sep), lines) + + # Check empty output. + if not splitted_lines: + _ThrowError("rbd showmapped returned empty output") + + # Check showmapped header line, to determine number of fields. + field_cnt = len(splitted_lines[0]) + if field_cnt != allfields: + _ThrowError("Cannot parse rbd showmapped output because its format" + " seems to have changed; expected %s fields, found %s", + allfields, field_cnt) + + matched_lines = \ + filter(lambda l: len(l) == allfields and l[volumefield] == volume_name, + splitted_lines) + + if len(matched_lines) > 1: + _ThrowError("The rbd volume %s is mapped more than once." + " This shouldn't happen, try to unmap the extra" + " devices manually.", volume_name) + + if matched_lines: + # rbd block device found. Return it. + rbd_dev = matched_lines[0][devicefield] + return rbd_dev + + # The given volume is not mapped. + return None + + def Assemble(self): + """Assemble the device. + + """ + pass + + def Shutdown(self): + """Shutdown the device. + + """ + if not self.minor and not self.Attach(): + # The rbd device doesn't exist. + return + + # Unmap the block device from the Volume. + self._UnmapVolumeFromBlockdev(self.unique_id) + + self.minor = None + self.dev_path = None + + def _UnmapVolumeFromBlockdev(self, unique_id): + """Unmaps the rbd device from the Volume it is mapped. + + Unmaps the rbd device from the Volume it was previously mapped to. + This method should be idempotent if the Volume isn't mapped. + + """ + pool = self.params[constants.LDP_POOL] + name = unique_id[1] + + # Check if the mapping already exists. + showmap_cmd = [constants.RBD_CMD, "showmapped", "-p", pool] + result = utils.RunCmd(showmap_cmd) + if result.failed: + _ThrowError("rbd showmapped failed [during unmap](%s): %s", + result.fail_reason, result.output) + + rbd_dev = self._ParseRbdShowmappedOutput(result.output, name) + + if rbd_dev: + # The mapping exists. Unmap the rbd device. + unmap_cmd = [constants.RBD_CMD, "unmap", "%s" % rbd_dev] + result = utils.RunCmd(unmap_cmd) + if result.failed: + _ThrowError("rbd unmap failed (%s): %s", + result.fail_reason, result.output) + + def Open(self, force=False): + """Make the device ready for I/O. + + """ + pass + + def Close(self): + """Notifies that the device will no longer be used for I/O. + + """ + pass + + def Grow(self, amount, dryrun): + """Grow the Volume. + + @type amount: integer + @param amount: the amount (in mebibytes) to grow with + @type dryrun: boolean + @param dryrun: whether to execute the operation in simulation mode + only, without actually increasing the size + + """ + if not self.Attach(): + _ThrowError("Can't attach to rbd device during Grow()") + + if dryrun: + # the rbd tool does not support dry runs of resize operations. + # Since rbd volumes are thinly provisioned, we assume + # there is always enough free space for the operation. + return + + rbd_pool = self.params[constants.LDP_POOL] + rbd_name = self.unique_id[1] + new_size = self.size + amount + + # Resize the rbd volume (Image) inside the RADOS cluster. + cmd = [constants.RBD_CMD, "resize", "-p", rbd_pool, + rbd_name, "--size", "%s" % new_size] + result = utils.RunCmd(cmd) + if result.failed: + _ThrowError("rbd resize failed (%s): %s", + result.fail_reason, result.output) + + DEV_MAP = { constants.LD_LV: LogicalVolume, constants.LD_DRBD8: DRBD8, constants.LD_BLOCKDEV: PersistentBlockDevice, + constants.LD_RBD: RADOSBlockDevice, } if constants.ENABLE_FILE_STORAGE or constants.ENABLE_SHARED_FILE_STORAGE: