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* polldaemon: improve support for interruptionsZdenek Kabelac2021-04-061-19/+16
| | | | | | Enhance handling of interruptions of polling process and lvmpoll daemon. Daemon should now react much faster on interrups (i.e. shutdown sequence) and avoid taking lenghty sleep waiting on pvmove signaling.
* lvpoll: improve merge pollingZdenek Kabelac2021-03-151-2/+7
| | | | | | | | When multiple polling tasks are watching for same LV, clearly when some of them wins the game - other polling tasks will fail. Improve the logic and report success if the merged LV is actually not a merging origin anymore (since likely someone else has already finished merging).
* pooldaemon: increase min polling intervalZdenek Kabelac2021-03-151-3/+3
| | | | | | | | | | Although we support '0' interval - it's highly inefficent to do so many scans in busy-loop. So ATM raise minimal rescan time to 100ms. TODO: revisit whole timing logic here as it does have some sideeffect hiddent impact and can considerably eat CPU in some cases.
* device usage based on devices fileDavid Teigland2021-02-231-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The LVM devices file lists devices that lvm can use. The default file is /etc/lvm/devices/system.devices, and the lvmdevices(8) command is used to add or remove device entries. If the file does not exist, or if lvm.conf includes use_devicesfile=0, then lvm will not use a devices file. When the devices file is in use, the regex filter is not used, and the filter settings in lvm.conf or on the command line are ignored. LVM records devices in the devices file using hardware-specific IDs, such as the WWID, and attempts to use subsystem-specific IDs for virtual device types. These device IDs are also written in the VG metadata. When no hardware or virtual ID is available, lvm falls back using the unstable device name as the device ID. When devnames are used, lvm performs extra scanning to find devices if their devname changes, e.g. after reboot. When proper device IDs are used, an lvm command will not look at devices outside the devices file, but when devnames are used as a fallback, lvm will scan devices outside the devices file to locate PVs on renamed devices. A config setting search_for_devnames can be used to control the scanning for renamed devname entries. Related to the devices file, the new command option --devices <devnames> allows a list of devices to be specified for the command to use, overriding the devices file. The listed devices act as a sort of devices file in terms of limiting which devices lvm will see and use. Devices that are not listed will appear to be missing to the lvm command. Multiple devices files can be kept in /etc/lvm/devices, which allows lvm to be used with different sets of devices, e.g. system devices do not need to be exposed to a specific application, and the application can use lvm on its own set of devices that are not exposed to the system. The option --devicesfile <filename> is used to select the devices file to use with the command. Without the option set, the default system devices file is used. Setting --devicesfile "" causes lvm to not use a devices file. An existing, empty devices file means lvm will see no devices. The new command vgimportdevices adds PVs from a VG to the devices file and updates the VG metadata to include the device IDs. vgimportdevices -a will import all VGs into the system devices file. LVM commands run by dmeventd not use a devices file by default, and will look at all devices on the system. A devices file can be created for dmeventd (/etc/lvm/devices/dmeventd.devices) If this file exists, lvm commands run by dmeventd will use it. Internal implementaion: - device_ids_read - read the devices file . add struct dev_use (du) to cmd->use_devices for each devices file entry - dev_cache_scan - get /dev entries . add struct device (dev) to dev_cache for each device on the system - device_ids_match - match devices file entries to /dev entries . match each du on cmd->use_devices to a dev in dev_cache, using device ID . on match, set du->dev, dev->id, dev->flags MATCHED_USE_ID - label_scan - read lvm headers and metadata from devices . filters are applied, those that do not need data from the device . filter-deviceid skips devs without MATCHED_USE_ID, i.e. skips /dev entries that are not listed in the devices file . read lvm label from dev . filters are applied, those that use data from the device . read lvm metadata from dev . add info/vginfo structs for PVs/VGs (info is "lvmcache") - device_ids_find_renamed_devs - handle devices with unstable devname ID where devname changed . this step only needed when devs do not have proper device IDs, and their dev names change, e.g. after reboot sdb becomes sdc. . detect incorrect match because PVID in the devices file entry does not match the PVID found when the device was read above . undo incorrect match between du and dev above . search system devices for new location of PVID . update devices file with new devnames for PVIDs on renamed devices . label_scan the renamed devs - continue with command processing
* improve reading and repairing vg metadataDavid Teigland2019-06-071-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fact that vg repair is implemented as a part of vg read has led to a messy and complicated implementation of vg_read, and limited and uncontrolled repair capability. This splits read and repair apart. Summary ------- - take all kinds of various repairs out of vg_read - vg_read no longer writes anything - vg_read now simply reads and returns vg metadata - vg_read ignores bad or old copies of metadata - vg_read proceeds with a single good copy of metadata - improve error checks and handling when reading - keep track of bad (corrupt) copies of metadata in lvmcache - keep track of old (seqno) copies of metadata in lvmcache - keep track of outdated PVs in lvmcache - vg_write will do basic repairs - new command vgck --updatemetdata will do all repairs Details ------- - In scan, do not delete dev from lvmcache if reading/processing fails; the dev is still present, and removing it makes it look like the dev is not there. Records are now kept about the problems with each PV so they be fixed/repaired in the appropriate places. - In scan, record a bad mda on failure, and delete the mda from mda in use list so it will not be used by vg_read or vg_write, only by repair. - In scan, succeed if any good mda on a device is found, instead of failing if any is bad. The bad/old copies of metadata should not interfere with normal usage while good copies can be used. - In scan, add a record of old mdas in lvmcache for later, do not repair them while reading, and do not let them prevent us from finding and using a good copy of metadata from elsewhere. One result is that "inconsistent metadata" is no longer a read error, but instead a record in lvmcache that can be addressed separate from the read. - Treat a dev with no good mdas like a dev with no mdas, which is an existing case we already handle. - Don't use a fake vg "handle" for returning an error from vg_read, or the vg_read_error function for getting that error number; just return null if the vg cannot be read or used, and an error_flags arg with flags set for the specific kind of error (which can be used later for determining the kind of repair.) - Saving an original copy of the vg metadata, for purposes of reverting a write, is now done explicitly in vg_read instead of being hidden in the vg_make_handle function. - When a vg is not accessible due to "access restrictions" but is otherwise fine, return the vg through the new error_vg arg so that process_each_pv can skip the PVs in the VG while processing. (This is a temporary accomodation for the way process_each_pv tracks which devs have been looked at, and can be dropped later when process_each_pv implementation dev tracking is changed.) - vg_read does not try to fix or recover a vg, but now just reads the metadata, checks access restrictions and returns it. (Checking access restrictions might be better done outside of vg_read, but this is a later improvement.) - _vg_read now simply makes one attempt to read metadata from each mda, and uses the most recent copy to return to the caller in the form of a 'vg' struct. (bad mdas were excluded during the scan and are not retried) (old mdas were not excluded during scan and are retried here) - vg_read uses _vg_read to get the latest copy of metadata from mdas, and then makes various checks against it to produce warnings, and to check if VG access is allowed (access restrictions include: writable, foreign, shared, clustered, missing pvs). - Things that were previously silently/automatically written by vg_read that are now done by vg_write, based on the records made in lvmcache during the scan and read: . clearing the missing flag . updating old copies of metadata . clearing outdated pvs . updating pv header flags - Bad/corrupt metadata are now repaired; they were not before. Test changes ------------ - A read command no longer writes the VG to repair it, so add a write command to do a repair. (inconsistent-metadata, unlost-pv) - When a missing PV is removed from a VG, and then the device is enabled again, vgck --updatemetadata is needed to clear the outdated PV before it can be used again, where it wasn't before. (lvconvert-repair-policy, lvconvert-repair-raid, lvconvert-repair, mirror-vgreduce-removemissing, pv-ext-flags, unlost-pv) Reading bad/old metadata ------------------------ - "bad metadata": the mda_header or metadata text has invalid fields or can't be parsed by lvm. This is a form of corruption that would not be caused by known failure scenarios. A checksum error is typically included among the errors reported. - "old metadata": a valid copy of the metadata that has a smaller seqno than other copies of the metadata. This can happen if the device failed, or io failed, or lvm failed while commiting new metadata to all the metadata areas. Old metadata on a PV that has been removed from the VG is the "outdated" case below. When a VG has some PVs with bad/old metadata, lvm can simply ignore the bad/old copies, and use a good copy. This is why there are multiple copies of the metadata -- so it's available even when some of the copies cannot be used. The bad/old copies do not have to be repaired before the VG can be used (the repair can happen later.) A PV with no good copies of the metadata simply falls back to being treated like a PV with no mdas; a common and harmless configuration. When bad/old metadata exists, lvm warns the user about it, and suggests repairing it using a new metadata repair command. Bad metadata in particular is something that users will want to investigate and repair themselves, since it should not happen and may indicate some other problem that needs to be fixed. PVs with bad/old metadata are not the same as missing devices. Missing devices will block various kinds of VG modification or activation, but bad/old metadata will not. Previously, lvm would attempt to repair bad/old metadata whenever it was read. This was unnecessary since lvm does not require every copy of the metadata to be used. It would also hide potential problems that should be investigated by the user. It was also dangerous in cases where the VG was on shared storage. The user is now allowed to investigate potential problems and decide how and when to repair them. Repairing bad/old metadata -------------------------- When label scan sees bad metadata in an mda, that mda is removed from the lvmcache info->mdas list. This means that vg_read will skip it, and not attempt to read/process it again. If it was the only in-use mda on a PV, that PV is treated like a PV with no mdas. It also means that vg_write will also skip the bad mda, and not attempt to write new metadata to it. The only way to repair bad metadata is with the metadata repair command. When label scan sees old metadata in an mda, that mda is kept in the lvmcache info->mdas list. This means that vg_read will read/process it again, and likely see the same mismatch with the other copies of the metadata. Like the label_scan, the vg_read will simply ignore the old copy of the metadata and use the latest copy. If the command is modifying the vg (e.g. lvcreate), then vg_write, which writes new metadata to every mda on info->mdas, will write the new metadata to the mda that had the old version. If successful, this will resolve the old metadata problem (without needing to run a metadata repair command.) Outdated PVs ------------ An outdated PV is a PV that has an old copy of VG metadata that shows it is a member of the VG, but the latest copy of the VG metadata does not include this PV. This happens if the PV is disconnected, vgreduce --removemissing is run to remove the PV from the VG, then the PV is reconnected. In this case, the outdated PV needs have its outdated metadata removed and the PV used flag needs to be cleared. This repair will be done by the subsequent repair command. It is also done if vgremove is run on the VG. MISSING PVs ----------- When a device is missing, most commands will refuse to modify the VG. This is the simple case. More complicated is when a command is allowed to modify the VG while it is missing a device. When a VG is written while a device is missing for one of it's PVs, the VG metadata is written to disk with the MISSING flag on the PV with the missing device. When the VG is next used, it is treated as if the PV with the MISSING flag still has a missing device, even if that device has reappeared. If all LVs that were using a PV with the MISSING flag are removed or repaired so that the MISSING PV is no longer used, then the next time the VG metadata is written, the MISSING flag will be dropped. Alternative methods of clearing the MISSING flag are: vgreduce --removemissing will remove PVs with missing devices, or PVs with the MISSING flag where the device has reappeared. vgextend --restoremissing will clear the MISSING flag on PVs where the device has reappeared, allowing the VG to be used normally. This must be done with caution since the reappeared device may have old data that is inconsistent with data on other PVs. Bad mda repair -------------- The new command: vgck --updatemetadata VG first uses vg_write to repair old metadata, and other basic issues mentioned above (old metadata, outdated PVs, pv_header flags, MISSING_PV flags). It will also go further and repair bad metadata: . text metadata that has a bad checksum . text metadata that is not parsable . corrupt mda_header checksum and version fields (To keep a clean diff, #if 0 is added around functions that are replaced by new code. These commented functions are removed by the following commit.)
* locking: unify global lock for flock and lockdDavid Teigland2019-04-291-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There have been two file locks used to protect lvm "global state": "ORPHANS" and "GLOBAL". Commands that used the ORPHAN flock in exclusive mode: pvcreate, pvremove, vgcreate, vgextend, vgremove, vgcfgrestore Commands that used the ORPHAN flock in shared mode: vgimportclone, pvs, pvscan, pvresize, pvmove, pvdisplay, pvchange, fullreport Commands that used the GLOBAL flock in exclusive mode: pvchange, pvscan, vgimportclone, vgscan Commands that used the GLOBAL flock in shared mode: pvscan --cache, pvs The ORPHAN lock covers the important cases of serializing the use of orphan PVs. It also partially covers the reporting of orphan PVs (although not correctly as explained below.) The GLOBAL lock doesn't seem to have a clear purpose (it may have eroded over time.) Neither lock correctly protects the VG namespace, or orphan PV properties. To simplify and correct these issues, the two separate flocks are combined into the one GLOBAL flock, and this flock is used from the locking sites that are in place for the lvmlockd global lock. The logic behind the lvmlockd (distributed) global lock is that any command that changes "global state" needs to take the global lock in ex mode. Global state in lvm is: the list of VG names, the set of orphan PVs, and any properties of orphan PVs. Reading this global state can use the global lock in sh mode to ensure it doesn't change while being reported. The locking of global state now looks like: lockd_global() previously named lockd_gl(), acquires the distributed global lock through lvmlockd. This is unchanged. It serializes distributed lvm commands that are changing global state. This is a no-op when lvmlockd is not in use. lockf_global() acquires an flock on a local file. It serializes local lvm commands that are changing global state. lock_global() first calls lockf_global() to acquire the local flock for global state, and if this succeeds, it calls lockd_global() to acquire the distributed lock for global state. Replace instances of lockd_gl() with lock_global(), so that the existing sites for lvmlockd global state locking are now also used for local file locking of global state. Remove the previous file locking calls lock_vol(GLOBAL) and lock_vol(ORPHAN). The following commands which change global state are now serialized with the exclusive global flock: pvchange (of orphan), pvresize (of orphan), pvcreate, pvremove, vgcreate, vgextend, vgremove, vgreduce, vgrename, vgcfgrestore, vgimportclone, vgmerge, vgsplit Commands that use a shared flock to read global state (and will be serialized against the prior list) are those that use process_each functions that are based on processing a list of all VG names, or all PVs. The list of all VGs or all PVs is global state and the shared lock prevents those lists from changing while the command is processing them. The ORPHAN lock previously attempted to produce an accurate listing of orphan PVs, but it was only acquired at the end of the command during the fake vg_read of the fake orphan vg. This is not when orphan PVs were determined; they were determined by elimination beforehand by processing all real VGs, and subtracting the PVs in the real VGs from the list of all PVs that had been identified during the initial scan. This is fixed by holding the single global lock in shared mode while processing all VGs to determine the list of orphan PVs.
* Remove lvmetadDavid Teigland2018-07-111-15/+7
| | | | | | | | | | | | | Native disk scanning is now both reduced and async/parallel, which makes it comparable in performance (and often faster) when compared to lvm using lvmetad. Autoactivation now uses local temp files to record online PVs, and no longer requires lvmetad. There should be no apparent command-level change in behavior.
* Remove unused clvm variations for active LVsDavid Teigland2018-06-071-2/+2
| | | | | | | | | | | | | | | | | | Different flavors of activate_lv() and lv_is_active() which are meaningful in a clustered VG can be eliminated and replaced with whatever that flavor already falls back to in a local VG. e.g. lv_is_active_exclusive_locally() is distinct from lv_is_active() in a clustered VG, but in a local VG they are equivalent. So, all instances of the variant are replaced with the basic local equivalent. For local VGs, the same behavior remains as before. For shared VGs, lvmlockd was written with the explicit requirement of local behavior from these functions (lvmlockd requires locking_type 1), so the behavior in shared VGs also remains the same.
* Merge branch 'master' into 2018-05-11-fork-libdmJoe Thornber2018-05-161-8/+3
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| * poll: add stdout fflush after poll queryZdenek Kabelac2018-05-121-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ATM it's a bit ugly to enforce flushing of 'stdio' here, but works as quick hot-fix. log_print*() is using buffered I/O. But for pooling with typical 1s interval this may take a while before buffer about continues progress gets flushed. So ATM fflush(). TODO: either add log_print*_with_flush() or maybe directly use just line buffering with log_print() and only log_debug() keep using buffered I/O mode.
| * dev_cache: drop open_listDavid Teigland2018-05-111-8/+0
| | | | | | | | | | | | devices are now held open only in bcache, so drop the dev_cache list of open devices which is unused.
* | build: Don't generate symlinks in include/ dirJoe Thornber2018-05-141-2/+2
|/ | | | | | | As we start refactoring the code to break dependencies (see doc/refactoring.txt), I want us to use full paths in the includes (eg, #include "base/data-struct/list.h"). This makes it more obvious when we're breaking abstraction boundaries, eg, including a file in metadata/ from base/
* pvmove: in fork mode destroy bcache in childDavid Teigland2018-04-251-2/+7
| | | | | | | When pvmove was run in background mode and forks instead of using lvmpolld, the child pvmove process was not clearing the bcache from the parent, so all the aio ops in the child were failing.
* lvmpolld: update to use new scanning correctlyDavid Teigland2018-04-201-0/+11
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* dev_cache: clean up scanDavid Teigland2018-04-201-5/+4
| | | | | Pull out all of the twisted logic and simply call dev_cache_scan at the start of the command prior to label scan.
* tidy: Add missing underscores to statics.Alasdair G Kergon2017-10-181-11/+11
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* tidy: prefer not using else after returnZdenek Kabelac2017-07-201-16/+17
| | | | | clang-tidy: avoid using 'else' after return - give more readable code, and also saves indention level.
* cleanup: use display_percentZdenek Kabelac2017-06-241-4/+4
| | | | Replace occurence of %.2f with call of display_percent function.
* toollib: make it possible to also process internal VGs, add ↵Peter Rajnoha2016-06-201-2/+2
| | | | | | | | | 'include_internal' switch to process_each_vg fn The lvm fullreport works per VG and as such, the vg, lv, pv, seg and pvseg subreport is done for each VG. However, if the PV is not part of any VG yet, we still want to display pv and pvseg subreports for these "orphan" PVs - so enable this for lvm fullreport's process_each_vg call.
* toollib: add 'parent' field to processing_handle; init report format only if ↵Peter Rajnoha2016-06-201-2/+2
| | | | | | | | | | | | | there's no parent If there's parent processing handle, we don't need to create completely new report group and status report - we'll just reuse the one already initialized for the parent. Currently, the situation where this matter is when doing internal report to do the selection for processing commands where we have parent processing handle for the command itself and processing handle for the selection part (that is selection for non-reporting tools).
* toollib: add vg name list arg to process_each_vgDavid Teigland2016-05-231-2/+2
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* poll daemon: only call lvmetad_connect when neededDavid Teigland2016-04-211-1/+1
| | | | | | When lvm is not using lvmetad, the lvmetad_connect() in the forked polling process is not needed and was generating unwanted warnings.
* lvmetad: connect from forked polling processDavid Teigland2016-04-201-0/+5
| | | | | | With commit 5e9e43074a6c, lvmetad connections are now made explicitly, so a new connection must be created from a child created for polling.
* lvconvert: show percent with %.2Zdenek Kabelac2016-04-061-2/+2
| | | | | lvm2 shows percent values with 2 decimal digits elsewhere so use it consistently also for this output.
* cleanup: poll better check for internal errorsZdenek Kabelac2016-02-251-10/+10
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* doc: change fsf addressZdenek Kabelac2016-01-211-1/+1
| | | | | Hmm rpmlint suggest fsf is using a different address these days, so lets keep it up-to-date
* vgextend: pass single vgname as process_each_vg argDavid Teigland2015-12-011-2/+2
| | | | | | | | | Pass the single vgname as a new process_each_vg arg instead of setting a cmd flag to tell process_each_vg to take only the first vgname arg from argv. Other commands with different argv formats will be able to use it this way.
* polldaemon: fix missing mirror in-sync info with lvmpolldOndrej Kozina2015-10-201-1/+6
| | | | | | | | | | | | | | | | | | CONVERTING status flag is a tricky one. It's not set when converting a non-mirror LV type to the mirror type, i.e.: linear -> two leg mirror. Also the conversion itself is instant and doesn't require to be polled. When mirror reaches sync state there's no final update on VG metadata for lvmpolld to be made thereby report_progress in fact doesn't report percentage of mirror being converted but percentage of mirror being in sync. Perhaps we should reword the lvconvert output here. On the other hand CONVERTING is set while we upconvert the mirror from i.e. two leg mirror to four leg mirror. In such case the operation is required to be polled so that lvmpolld can cleanup temporary conversion log when the conversion is over. Ignore CONVERTING lv_type for the moment and match LVs only by uuids during 'mirror conversion'/'waiting for a sync to finish'.
* lockd: no error when unlock failsDavid Teigland2015-08-181-4/+2
| | | | | | The unlock call will fail in expected and normal cases, and should not cause the command to fail. (An actual unlock in the lock manager should never fail.)
* lockd: check for failing unlockZdenek Kabelac2015-08-181-2/+7
| | | | Avoid ignoring unlocking error.
* coverity: variable init must be done before its usePeter Rajnoha2015-08-041-2/+3
| | | | | tools/polldaemon.c:465: uninit_use_in_call: Using uninitialized value "id.vg_name" when calling "print_log". tools/polldaemon.c:465: uninit_use_in_call: Using uninitialized value "id.lv_name" when calling "print_log".
* lvconvert: merge polling fixes for lockdDavid Teigland2015-07-221-27/+34
| | | | | | | | | | | . the poll check will eventually call finish which will write the VG, so an ex VG lock is needed from lvmlockd. . fix missing unlock on poll error path . remove the lockd locking while monitoring the progress of the command, as suggested by the earlier FIXME comment, as it's not needed.
* coverity: fix NULL check in lv->lvid.sPeter Rajnoha2015-07-081-1/+1
| | | | | | | tools/polldaemon.c:457: array_null: Comparing an array to null is not useful: "lv->lvid.s" The lv->lvid.s is never NULL. The check was supposed to be *lv->lvid.s to check if the string is not empty.
* coverity: fix missing initializationPeter Rajnoha2015-07-081-2/+2
| | | | | | | | | | | ... Using uninitialized value "lockd_state" when calling "lockd_vg" (even though lockd_vg assigns 0 to the lockd_state, but it looks at previous state of lockd_state just before that so we need to have that properly initialized!) libdm/libdm-report.c:2934: uninit_use_in_call: Using uninitialized value "tm". Field "tm.tm_gmtoff" is uninitialized when calling "_get_final_time". daemons/lvmlockd/lvmlockctl.c:273: uninit_use_in_call: Using uninitialized element of array "r_name" when calling "format_info_r_action". (just added FIXME as this looks unfinished?)
* include: Standardise around new tool.h.Alasdair G Kergon2015-07-061-2/+3
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* Add lvmlockddev-dct-lvmlockd-AZDavid Teigland2015-07-021-7/+40
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* polldaemon.c: modify log levels in report_progressOndrej Kozina2015-05-211-14/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a race when asking lvmpolld about progress_status and actually reading the progress info from kernel: Even with lvmpolld being used we read status info from LVM2 command issued by a user (client side from lvmpolld perspective). The whole cycle may look like following: 1) set up an operation that requires polling (i.e. pvmove /dev/sda) 2) notify lvmpolld about such operation (lvmpolld_poll_init()) 3) in case 1) was not called with --background it would continue with: 4) Ask lvmpolld about progress status. it may respond with one of: a) in_progress b) not_found c) finished d) any low level error 5) provided the answer was 4a) try to read progress info from polling LV (i.e. vg00/pvmove1). Repeat steps 4) and 5) until the answer is != 4a). And now we got into racy configuration: lvmpolld answered with in_progress but it may be the that in_between 4) and 5) the operation has already finished and polling LV is already gone or there's nothing to ask for. Up to now, 5) would report warning and it could print such warning many times if --interval was set to 0. We don't want to scary users by warnings in such situation so let's just print these messages in verbose mode. Error messages due to error while reading kernel status info (on existing, active and locked LV) remained the same.
* polldaemon.c: do not report error when LV not foundOndrej Kozina2015-05-191-10/+8
| | | | | | | | | | currently in wait_for_single_lv() fn trying to poll missing pvmove LV is considered success. It may have been already finished by another instance of polldaemon. either by another forked off polldaemon or by lvmpolld. Let's try to handle the mirror conversion and snapshot merge the same way.
* polldaemon: remove get_copy_vg and get_copy_lv wrappersDavid Teigland2015-05-191-26/+0
| | | | | | | | These wrappers have been replaced by direct calls to vg_read() and find_lv() in previous commits. This commit should have no functional impact since all bits were already unreachable.
* polldaemon.c: call find_lv directlyOndrej Kozina2015-05-191-4/+20
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* polldaemon.c: call vg_read directlyDavid Teigland2015-05-191-2/+2
| | | | replace calls in wait_for_single_lv() and report_progress() fns
* polldaemon: move dev_close_all out of poll_get_copy_vgOndrej Kozina2015-05-191-2/+9
| | | | | | | | let's call dev_close_all() only before we're about to 'sleep' for at least one second during the polling. (it's questionable whether to call dev_close_all() at all in polldaemon code. Natural extension would be to drop it completely)
* lvmpolld: Add standalone polldaemon.Ondrej Kozina2015-05-091-4/+177
| | | | See doc/lvmpolld_overview.txt
* polldaemon: make wait_for_single_lv publicOndrej Kozina2015-05-051-3/+3
| | | | | referenced by new lvpoll command after lvmpolld gets merged.
* polldaemon: introduce _nanosleep functionOndrej Kozina2015-05-051-3/+18
| | | | | | | querying future lvmpolld with zero wait time is highly undesirable and can cause serious performance drop of the future daemon. The new wrapper function may avoid immediate return from syscal by introducing minimal wait time on demand.
* polldaemon: refactor polling interfacesOndrej Kozina2015-05-051-32/+90
| | | | | | | | | | | | | | | Routines responsible for polling of in-progress pvmove, snapshot merge or mirror conversion each used custom lookup functions to find vg and lv involved in polling. Especially pvmove used pvname to lookup pvmove in-progress. The future lvmpolld will poll each operation by vg/lv name (internally by lvid). Also there're plans to make pvmove able to move non-overlaping ranges of extents instead of single PVs as of now. This would also require to identify the opertion in different manner. The poll_operation_id structure together with daemon_parms structure they identify unambiguously the polling task.
* polldaemon: optimise out waiting after pollingOndrej Kozina2015-05-051-1/+1
| | | | | | | | | | Waiting even after _check_lv_status returned success and 'finished' flag was set to true doesn't make much sense. Note that while we skip the wait() we also skip the init_full_scan_done(0) inside the routine. This should have no impact as long as the code after _wait_for_single_lv doesn't presume anything about the state of the cache.
* polldaemon: get get_copy_vg ready for refactoringOndrej Kozina2015-05-051-4/+5
| | | | | with refactored code we take some VG locks as read-only. Make the poll_get_copy_vg ready for the change.
* polldaemon: respect lv_attr parm in poll_get_copy_lvOndrej Kozina2015-05-041-2/+2
| | | | | | | | | as a part of bigger effort to unify polling intefaces poll_get_copy_lv should be able to look up LVs based on theirs lv->status field. Effective after pvmove starts using poll_get_copy_lv fn as well.
* polldaemon: move lvconvert_get_copy_lv codeOndrej Kozina2015-05-041-0/+14
| | | | | Moving lvconvert_get_copy_lv to polldaemon (poll_get_copy_lv). Clear move and rename.