IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
Since configure.h is a generated header and it's missing traditional
ifdefs preambule - it can be included & parsed multiple times.
Normally compiler is fine when defines have same value and there is
no warning - yet we don't need to parse this several times
and by adding -include directive we can ensure every file
in the package is rightly compile with configure.h as the
first header file.
When a VG is exported, the 'fullreport' returns an exit code of 5, but
otherwise returns the data we are wanting.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
In some cases we get stuck where we are unable to retrieve the current
state of lvm as we are encountering an error. When the error is
persistent we will log and exit the daemon instead of consuming vast
amounts of resources.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
A bit of chicken & egg problem - dmeventd needs to use old libdm library.
VDO is only part of new device_mapper internal library.
So include directly source file for parsing status - this fixes usability
problem of VDO plugin introduced with previous Makefile reshaping
patchset.
NOTE: source file needs to be keep then compilable in both environments.
Also add missing copyright header.
Since there is very little change there will be any new devel going
to happing with cmirror - avoid eating extra disk space and link
with already installed libdm which implements all use basic
function of dm list
Since dmeventd is 'libdm' based project, it needs to link
libdm library instead of its internal version
An external users may provide plugins loadeable by dmeventd.
So external user of libdevmapper-event library has no other option
then to link with released libdevmapper library.
The complexity comes with lvm2 plugins.
The lvm2 plugin itself uses internal version of device_mapper,
but libdevmapper-event usage is libdm based - so there needs to be avoided
any breakage on compatibility of internal i.e. dm_task_run structures.
TODO: most likely dmeventd itself should be moved into libdm/dm-tools dir,
and only lvm2 plugins should be created as part of lvm project,
but those still need to link with libdevmapper.
If we don't know the meaning we will return the key with default text
instead of raising an exception and taking the daemon out in the
process.
Resolves: rhbz1657950
When we get bug reports we may not get the entire log, so lets
dump the fight recorder from newest to oldest as the one we
are interested in was likely to be the last command run.
Ensure configure.h is always 1st. included header.
Maybe we could eventually introduce gcc -include option, but for now
this better uses dependency tracking.
Also move _REENTRANT and _GNU_SOURCE into configure.h so it
doesn't need to be present in various source files.
This ensures consistent compilation of headers like stdio.h since
it may produce different declaration.
When sanlock_release returns an error because of an i/o
timeout releasing the lease on disk, lvmlockd should just
consider the lock released. sanlock will continue trying
to release the lease on disk after the original request
times out.
The choice about sector size and lease align size is
now made by the sanlock user, in this case lvmlockd.
This will allow lvmlockd to use other lease sizes in
the future. This also prevents breakage if hosts
report different sector sizes, or the sector size
reported by a device changes.
Thin plugin started to use configuble setting to allow to configure
usage of external scripts - however to read this value it needed to
execute internal command as dmeventd itself has no access to lvm.conf
and the API for dmeventd plugin has been kept stable.
The call of command itself was not normally 'a big issue' until users
started to use higher number of monitored LVs and execution of command
got stuck because other monitored resource already started to execute
some other lvm2 command and become blocked waiting on VG lock.
This scenario revealed necesity to somehow avoid calling lvm2 command
during resource registration - but this requires bigger changes - so
meanwhile this patch tries to minimize the possibility to hit this race
by obtaining any configurable setting just once - such patch is small
and covers majority of problem - yet better solution needs to be
introduced likely with bigger rework of dmeventd.
TODO: avoid blocking registration of resource with execution of lvm2
commands since those can get stuck waiting on mutexes.
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.
Introduce VDO plugin for monitoring VDO devices.
This plugin can be used also by other users, as plugin checks
for UUID prefix 'LVM-' and run lvm actions only on those
devices.
Non LVM- device are only monitored and log warnings
when usage threshold reaches 80%.
When the lvmlockd lock is shared, upgrade it to ex
when repair (writing) is needed during vg_read.
Pass the lockd state through additional read-related
functions so the instances of repair scattered through
vg_read can be handled.
(Temporary solution until the ad hoc repairs can be
pulled out of vg_read into a top level, centralized
repair function.)
The device-mapper directory now holds a copy of libdm source. At
the moment this code is identical to libdm. Over time code will
migrate out to appropriate places (see doc/refactoring.txt).
The libdm directory still exists, and contains the source for the
libdevmapper shared library, which we will continue to ship (though
not neccessarily update).
All code using libdm should now use the version in device-mapper.
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/
The clvmd saved_vg data is independent from the normal lvm
lvmcache vginfo data, so separate saved_vg from vginfo.
Normal lvm doesn't need to use save_vg at all, and in clvmd,
lvmcache changes on vginfo can be made without worrying
about unwanted effects on saved_vg.
I don't like having this in a common header because it means you end
up including too much and causing unneccessary dependencies. eg,
lib/misc/lib.h includes libdevmapper.h, internationalisation, and
logging stuff.
There are likely more bits of code that can be removed,
e.g. lvm1/pool-specific bits of code that were identified
using FMT flags.
The vgconvert command can likely be reduced further.
The lvm1-specific config settings should probably have
some other fields set for proper deprecation.
Recent changes allow some major simplification of the way
lvmcache works and is used. lvmcache_label_scan is now
called in a controlled fashion at the start of commands,
and not via various unpredictable side effects. Remove
various calls to it from other places. lvmcache_label_scan
should not be called from anywhere during a command, because
it produces an incorrect representation of PVs with no MDAs,
and misclassifies them as orphans. This has been a long
standing problem. The invalid flag and rescanning based on
that is no longer used and removed. The 'force' variation is
no longer needed and removed.
We can't let clvmd keep all scanned devs open,
which prevents them from being removed. So
drop the bcache data (and close fds) affter
doing a label scan.
Also set up bcache before the clvm-specific
vg_read (which needs to rescan the vg's devs
using bcache) and destroy the bcache after.
Since this function is called with 'fd == -1', but Coverity can't see
this path can't be visited with this argument, add explicit check for
valid descriptor.
When dmeventd thin plugin forks a configurable script, switch to use
execvp to pass whole environment present to dmeventd - so all configured
paths present at dmeventd startup are visible to script.
This was likely not a problem for common user enviroment,
however in test suite case variable like LVM_SYSTEM_DIR were
not actually used from test itself but rather from
a system present lvm.conf and this may have cause strange
behavior of a testing script.
Avoid using same return code for reporting 2 different things
and stricly report error code by return value and add new
parameter for reporting monitoring status.
This makes easier to recognize which error we got from dm_event
and continue only with ENOENT.
lvmdbusd executable script must use python3 interpreter detected by
configure script, as site-packages directory used for library is only
used by that interpreter.
When sanlock or dlm lock managers return an error number
that we don't recognize, replace it with a generic -ELMERR
which is defined in the set of special lvmlockd error
numbers. Otherwise, an unknown lock manager error number
could be misinterpreted for something else if it happened
to overlap another set of error numbers (which they have
not thus far.)
These less common errors returned from sanlock should
also cause sanlock to retry the lock acquire:
- i/o timeout occurs during sanlock_acquire().
other i/o on the same disk as the leases can cause
sanlock i/o timeouts.
- low level disk paxos contention between hosts naturally
causes one host to not acquire the lease. There are a
couple special error numbers associated with these cases
that should just be recognized as a normal failure to
acquire the lease.
In HA cluster, we have "clvm" resource agent to manage clvmd daemon.
The agent invokes clvmd like: "clvmd -T90 -d0", which always prints
a scaring error message:
"""
local socket: connect failed: No such file or directory
"""
When specifed with "-d" option, clvmd tries to check if an instance
of the clvmd daemon is already running through a testing connection.
The connect() will fail with this ENOENT error in such case, so supress
the error message in such case.
TODO: add missing error reaction code - since ofter log_error, program
is not supposed to continue running (log_error() is for reporting
stopping problems).
Signed-off-by: Eric Ren <zren@suse.com>
When dmeventd receives SIGTERM/INT/HUP/QUIT it validates if exit is possible.
If there was any device still monitored, such exit request used to
be ignored/refused. This 'usually' worked reasonably well, however if there
is very short time period between last device is unmonitored and signal
reception - there was possibility such EXIT was ignored, as dmeventd has
not yet got into idle state even commands like 'vgchange -an' has already
finished.
This patch changes logic towards scheduling EXIT to the nearest
point when there is no monitored device.
EXIT is never forgotten.
NOTE: if there is only a single monitored device and someone sends
SIGTERM and later someone uses i.e. 'lvchange --refresh' after
unmonitoring dmeventd will exit and new instance needs to be
started.
If you send a SIGUSR1 (10) to the daemon it will dump all the
threads current stacks to stdout. This will be useful when the
daemon is apparently hung and not processing requests.
eg.
$ sudo kill -10 <daemon pid>
Make sure that any and all code that executes in the main thread is
wrapped with a try/except block to ensure that at the very least
we log when things are going wrong.
In some cases we are seeing where there are no VGs, but the data returned from
lvm shows that the PVs have the following for the VG:
"vg_name":"[unknown]", "vg_uuid":""
The code was only checking for the exitence of the VG name and we called into
the function get_object_path_by_uuid_lvm_id which requires both the VG name and
the LV name to exist (asserts this) which results in the following stack trace:
Traceback (most recent call last):
File "/home/tasleson/lvm2/daemons/lvmdbusd/utils.py", line 563, in runner
obj._run()
File "/home/tasleson/lvm2/daemons/lvmdbusd/utils.py", line 584, in _run
self.rc = self.f(*self.args)
File "/home/tasleson/lvm2/daemons/lvmdbusd/fetch.py", line 26, in
_main_thread_load
cache_refresh=False)[1]
File "/home/tasleson/lvm2/daemons/lvmdbusd/pv.py", line 48, in load_pvs
emit_signal, cache_refresh)
File "/home/tasleson/lvm2/daemons/lvmdbusd/loader.py", line 37, in common
objects = retrieve(search_keys, cache_refresh=False)
File "/home/tasleson/lvm2/daemons/lvmdbusd/pv.py", line 40, in
pvs_state_retrieve
p["pv_attr"], p["pv_tags"], p["vg_name"], p["vg_uuid"]))
File "/home/tasleson/lvm2/daemons/lvmdbusd/pv.py", line 84, in __init__
vg_uuid, vg_name, vg_obj_path_generate)
File "/home/tasleson/lvm2/daemons/lvmdbusd/objectmanager.py", line 318,
in get_object_path_by_uuid_lvm_id
assert uuid
AssertionError
When executing in the main thread, if we encounter an exception we
will bypass the notify_all call on the condition and the calling thread
never wakes up.
@staticmethod
def runner(obj):
# noinspection PyProtectedMember
Exception thrown here
----> obj._run()
So the following code doesn't run, which causes calling thread to hang
with obj.cond:
obj.function_complete = True
obj.cond.notify_all()
Additionally for some unknown reason the stderr is lost.
Best guess is it's something to do with scheduling a python function
into the GLib.idle_add. That made finding issue quite difficult.
ATM we have several instances of daemonizing code.
Each has its 'special' logic so not completely easy
to unify them all into a single routine.
Start to unify them and use one strategy for rediricting
all input/outpus to /dev/null - use 'dup2' function for this
and open /dev/null before fork to make sure it's available.
gcc warns here about storring 69 bytes in 64 byte array (losing
potentially 4 bytes from 'ls->name').
lvmlockd-core.c:2657:36: warning: ‘%s’ directive output may be truncated writing up to 64 bytes into a region of size 60 [-Wformat-truncation=]
snprintf(tmp_name, MAX_NAME, "REM:%s", ls->name);
^~
lvmlockd-core.c:2657:2: note: ‘snprintf’ output between 5 and 69 bytes into a destination of size 64
snprintf(tmp_name, MAX_NAME, "REM:%s", ls->name);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Replaced with slightly better code - but it still misses error path what
to do if the name would be truncated... - so added FIXME.
Also using all bytes for snprintf() buffer size
(as the size is with \0 included)
currently, lvcreate for sanlock find the free lock offset
from the beginning of the lvmlock every time.
after created thousands of lvs, it will issue thousands of read
ios for lvcreate to find free lock offset.
remeber the last free lock offset will greatly reduce the impact
Signed-off-by: Zhang Huan <zhanghuan@huayun.com>
Check first if we need to even link -lrt - since clock functions
are normally emebeded with recent glibc (>=2.17)
Use standard RT_LIBS name.
Avoid duplicate test for realtime clock with lvmlockd
Show better error message when realtime clock support is missing or
disabled.
Link RT_LIBS explicitely with lvmlockd and lvmetad.
Avoid adding -g more then once for debug builds.
Avoid enabling DEBUG_MEM when we build multithreaded tools.
Link executables with -fPIE -pie and --export-dynamic LDFLAGS
Introduce PROGS_FLAGS to add option to pass flags for external libs.
Link lvm2 internally library only when really used.
Link DAEMON_LIBS with daemons.
Pass VALGRIND_CFLAGS internally
Set shell failure mode on couple places.
API for strtod() or strtoul() needs reset of errno, before it's being
called. So add missing resets in missing places and some also some
errno validation for out-of-range numbers.
Avoid reading already released memory and do a continue directly.
Invalid read of size 1
at 0x1201B0: main_loop (clvmd.c:931)
by 0x11F640: main (clvmd.c:666)
Address 0x72ddef0 is 32 bytes inside a block of size 224 free'd
at 0x4C30D18: free (vg_replace_malloc.c:530)
by 0x54D6FD1: dm_free_wrapper (dbg_malloc.c:357)
by 0x122E6E: process_work_item (clvmd.c:2034)
by 0x123003: lvm_thread_fn (clvmd.c:2085)
by 0x590A3A8: start_thread (pthread_create.c:465)
by 0x5C3C7FE: clone (in /usr/lib64/libc-2.25.90.so)
Block was alloc'd at
at 0x4C2FB6B: malloc (vg_replace_malloc.c:299)
by 0x54D6EF1: dm_malloc_aux (dbg_malloc.c:286)
by 0x54D6F1C: dm_zalloc_aux (dbg_malloc.c:291)
by 0x54D6F96: dm_zalloc_wrapper (dbg_malloc.c:345)
by 0x11F89C: local_rendezvous_callback (clvmd.c:731)
by 0x1203D2: main_loop (clvmd.c:964)
by 0x11F640: main (clvmd.c:666)
Initialize mutex upfront any debugging and fix this report:
Mutex reinitialization: mutex 0x485d20, recursion count 0, owner 1.
at 0x4C38480: pthread_mutex_init_intercept (drd_pthread_intercepts.c:821)
by 0x4C38480: pthread_mutex_init (drd_pthread_intercepts.c:830)
by 0x11F359: main (clvmd.c:562)
mutex 0x485d20 was first observed at:
at 0x4C38F63: pthread_mutex_lock_intercept (drd_pthread_intercepts.c:885)
by 0x4C38F63: pthread_mutex_lock (drd_pthread_intercepts.c:898)
by 0x11E920: debuglog (clvmd.c:254)
by 0x11F1D8: main (clvmd.c:527)
1. dm_uuid is 68 byte length, but buf is 64 which
will cause miss match uuid from lv lock manager
2. no lv lock_type path in dm config, use lock_args instead
Signed-off-by: Zhang Huan <zhanghuan@chinac.com>
Centralise editing of the client list into _add_client() and
_del_client(). Introduce _local_client_count to track the size of the
list for debugging purposes. Simplify and standardise the various ways
the list gets walked.
While processing one element of the list in main_loop(),
cleanup_zombie() may be called and remove a different element, so make
sure main_loop() refreshes its list state on return. Prior to this
patch, the list edits for clients disappearing could race against the
list edits for new clients connecting and corrupt the list and cause a
variety of segfaults.
An easy way to trigger such failures was by repeatedly running shell
commands such as:
lvs &; lvs &; lvs &;...;killall -9 lvs; lvs &; lvs &;...
Situations that occasionally lead to the failures can be spotted by
looking for 'EOF' with 'inprogress=1' in the clvmd debug logs.
When we want to report primary leg failure, check for intial 'a',
since otherwice 'Aa idle' is normally visible.
Also reset array of bit flags marking dead devices, once
plugin detects raid is in sync.
Functionality of ignore suspend devices is already granted by:
lvm2_disable_dmeventd_monitoring() -> init_run_by_dmeventd() ->
init_ignore_suspended_devices().
In fact plugins should never use --config because it has
some unpleasant technical issues.
Add the checks necessary to distiguish the state of a RAID when the primary
source for syncing fails during the "recover" process.
It has been possible to hit this condition before (like when converting from
2-way RAID1 to 3-way and having the first two devices die during the "recover"
process). However, this condition is now more likely since we treat linear ->
RAID1 conversions as "recover" now - so it is especially important we cleanly
handle this condition.
The file block count stored in the filemap_monitor was lazily
initialised at the time of the first check. This causes problems
in the case that the file has been truncated between this time and
the time the daemon started: the initial block count and current
block count match and the daemon fails to detect a change.
Separate the setting of the block count from the check and make a
call to update the value at the start of _dmfilemapd().
If during the process of fetching current lvm state we experience an
exception we fail to call set_result on the queued_requests we were
processing. When this happens those threads block forever which causes
the service to stall infinitely. Only clear the queued_requests after
we have called set_result.
We were not adding background tasks to flight recorder. Add the meta
data to the flight recorder when we start the command and update the meta
data when the command is finished. Locking was added to meta data to
prevent concurrent update and returning string representation as these can
happen in two different threads.
vgreduce previously allowed --all and --removemissing together even though
it only actual did the remove missing. The lvm dbus daemon was passing
--all anytime there was no entries in pv_object_paths. This change supplies
--all if and only if we are not removing missing and the pv_object_paths
is empty.
Vgreduce has and continues to enforce the invalid combination of supplying a
device list when you specify --all or --removemissing so we do not need
to check for that invalid combination explicitly in the lvm dbus service as
it's already covered.
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1455471
With recent updates for thin pool monitoring in version 169
we lost multiple WARNINGs to be printed in syslog, when
pool crossed 80%, 85%, 90%, 95%, 100%.
Restore this logic as we want to keep user informed more
then just once when 80% boundary is passed.
Fix a regression introduced in 70bb726 that allows a local variable
in the monitored file checking routine to be accessed before its
assignment when the file has already been unlinked.
When a user does a Manager.PvCreate they can specify the block device using a
device path that may be different than what lvm reports is the device path. For
example a user could use:
/dev/disk/by-id/wwn-0x5002538500000000 instead of /dev/sdc
In this case the pvcreate will succeed, but when we query lvm we don't find the
newly created PV. We fail because it's device path is returned as /dev/sdc. This
change re-uses an internal lookup which can accommodate this and correctly find
the newly created PV.
Corrects https://bugzilla.redhat.com/show_bug.cgi?id=1445654
Adding qualifier makes the only unqualified log_debug occurence
consistent with other uses in the same file.
Other possible ways to fix this:
- using `from .utils import log_debug`
- moving the line below `from . import utils` line
Since _filemap_monitor_set_notify() is only called after daemon
start up it should not use the _early_log() macros. Instead, use
log_sys_error to log errors from the two syscalls in the function.
The function _filemap_monitor_check_file_unlinked() attempts to
test whether a fd value should be closed by comparison to zero:
if ((fd > 0) && close(fd))
log_error("Error closing fd %d", fd);
The test should be '>=' since 0 is a valid file descriptor.
Similar to 40fb91a, but for the file descriptor opened using the
link path reported by /proc/<self>/fd/<fd>.
The daemon opens a new file descriptor from /proc/<self>/fd when
checking for an unlinked file with mode=inode. Ensure that it is
always closed even if the same file test fails.
The daemon opens a new file descriptor from fm->path when checking
for an unlinked file with mode=inode. Ensure that it is always
closed even if the same file test fails.
The path argument check in dmfilemapd incorrectly tests for:
if (argv[0] == '/')
Rather than testing the 1st character in the string pointed to by
argv[0].
Udev events can come in like a flood when something changes. It really
doesn't do us any good to refresh the state of the service numerous times
when 1 would suffice. We had something like this before, but it was
removed when we added the refresh thread. However, we have since learned
that we need to sequence events in the correct order and block dbus
operations if we believe the state has been affected, thus udev events are
being processed on the main work queue. This change limits spurious
work items from getting to the queue.
If we always disable the sending of notify dbus events then in the case
where all the users are lvm dbus users we will be in udev handling mode
until at least 1 external lvm command occurs. Instead we will not disable
notify dbus until after we get at least 1 external event. This makes the
service get into the correct mode of operation faster.
Previous commit 506d88a2ec introduced disabling lvmetad on repairs.
Avoid calling lvscan and use of any --config options altogether
in the mirror and raid DSOs.
Related: rhbz1380521
Repairing missing devices does not work reliably
with lvmetad, so disable lvmetad before repair.
A standard lvmetad refresh (pvscan --cache) will
enable lvmetad again.
Commit 07ded8059c assumed that the mirror is blocked which is not the case.
It is accessible, degraded and in need of repair because some of its legs
(partially) failed. Any auto-repair via dmeventd fails though because
of lvmetad not providing proper data about the failed PV(s). That's why
this workaround got introduced in commit 76f6951c3e until we get to
the lvmetad interaction core issue.
Mind any mirror auto-repair failure is caused by such lvmetad interaction
problems not yet solved so disabling lvmetad works as a resort as elaborated
on in the related bz.
Reintroducing the interim solution.
Resolves: rhbz1380521
Effectively revert whole 76f6951c3e.
We need to figure out some other solution.
At this moment usage of --config with 'repair' of blocked mirror
is 'freezing' combination.
Require that the path argument to dmfilemapd be an absolute path
and document this in tool output, libdevmapper.h and dmfilemapd.8.
The check is also enforced by dm_stats_start_filemapd() to avoid
forking a new process with an invalid path argument.
The initial check on argc incorrectly returns 1 when the wrong
number of arguments are present, causing a segfault in main()
when no arguments are given:
# dmfilemapd
Wrong number of arguments.
usage: dmfilemapd <fd> <group_id> <path> <mode> [<foreground>[<log_level>]]
Segmentation fault (core dumped)
Utilizing the --config option we will utilize global/notify_dbus=0 so
that the service itself doesn't generate change events which it then needs to
process.
We need to place query operations in the queue to prevent the case where
a client knows of something before the service does. For example if a
client creates a PV/VG/LV outside of the dbus API and then immediately
tries to lookup and use that resource in the lvm dbus service it should
be present. By placing the queries in the work queue any previous
refresh operation will complete before we process the query.
The filemap daemon takes its program_id from the regions it is
managing: use DM_STATS_ALL_PROGRAMS when retrieving an initial
listing and then obtain the correct program_id from the group
leader.
Automatic dmeventd repair of mirrors with active lvmetad configured
(mirror_image_fault_policy = "allocate") fails because the lvscan
run before the repair in the mirror DSO does not update the
lvmetad cache properly thus "lvconvert --repair ..." fails.
Need to scan the mirror LV before and after the repair
to have proper cache content after the repair finished.
The cache can't be relied on or the repair will fail.
Resolves: rhbz1380521
Add a daemon that can be launched to monitor a group of regions
corresponding to the extents of a file, and to update the regions as the
file's allocation changes.
The daemon is intended to be started from a library interface, but can
also be run from the command line:
dmfilemapd <fd> <group_id> <path> <mode> [<foreground>[<log_level>]]
Where fd is a file descriptor open on the mapped file, group_id is the
group identifier of the mapped group and mode is either "inode" or
"path". E.g.:
# dmfilemapd 3 0 vm.img inode 1 3 3<vm.img
...
If foreground is non-zero, the daemon will not fork to run in the
background. If verbose is non-zero, libdm and daemon log messages will
be printed.
It is possible for the group identifier to change when regions are
re-mapped: this occurs when the group leader is deleted (regroup=1 in
dm_stats_update_regions_from_fd()), and another region is created before
the daemon has a chance to recreate the leader region.
The operation is inherently racey since there is currently no way to
atomically move or resize a dm_stats region while retaining its
region_id.
Detect this condition and update the group_id value stored in the
filemap monitor.
A function is also provided in the the stats API to launch the filemap
monitoring daemon:
int dm_stats_start_filemapd(int fd, uint64_t group_id, const char *path,
dm_filemapd_mode_t mode, unsigned foreground,
unsigned verbose);
This carries out the first fork and execs dmfilemapd with the arguments
specified.
A dm_filemapd_mode_t value is specified by the mode argument: either
DM_FILEMAPD_FOLLOW_INODE, or DM_FILEMAPD_FOLLOW_PATH. A helper function,
dm_filemapd_mode_from_string(), is provided to parse a string containing
a valid mode name into the appropriate dm_filemapd_mode_t value.
Some archs can use even 64K pages and then lvm2 runs into trouble if
the stack is 'too small' to fit extra page capturing stack overwrite.
So when lvm2 limits stack - add extra mem page - be it 4K or 64K.
Relates to ppc64le bug: https://bugzilla.redhat.com/1387279
For more advanced support we need to ensure better logic for calling
external much more advanced script for maintanance of thin-pool.
So this new code ensures:
When thin-pool data or metadata is bigger then 50%,
then with each 5% increment, action is called.
This is independent from autoextend_threshold.
This action always happens when thin-pool is over threshold,
(so no action when it's exactly i.e. 60%).
The only exception is 100% full thin-pool - which invokes 'last'
action.
Since thin-pool occupancy may change also downward, code needs
to also handle possibly reduction of occupancy of thin-pool.
So when usage drop from 90% to 50%, thin-pool will start to call
again action when it will pass 55% threshold.
This give external commands lot of option i.e. to call 'fstrim'
before actual resize is needed.
Default internal logic will stop trying to do any 'rescue' action
when executed command fails.
This will be now fully in hands of external script if such
behaviour is needed.
Instead of stopping monitoring after couple failing retries,
keep monitoring forever, just make larger delays between command
retries (ATM upto ~42 minutes).
So syslog is not spammed too often, yet commands have a chance to
be retried and succeed eventually...
When dmeventd configured command does not start with 'lvm ' prefix,
it's going to be an 'external' command.
In this case we split command by spaces to argv strings.
When thin-pool processes event and 'lvextend --use-policies' fails
rather capture up-to-date new info as the fullness percentage may
have jumped noticable. This way we could use 'more' correct numbers
when checking for thresholds.
The function timeout_add_seconds has quite a bit of variability. Using
timeout_add which specifies the timeout in ms instead of seconds. Testing
shows that this is much more consistent which should improve clients that
are using shorter timeouts for the API and the connection.
Added a properties changed signal on the job dbus object so that client
can wait for a signal that the job is complete instead of polling or
blocking on the wait method.
Allows the user to override the number of commands that get dumped
to the log when we encounter a lvm error. Also useful during
development when you don't want to see the blackbox output.
When reading data from stdout & stderr we were reading until the
reading until we got None back which really isn't needed as the
read will return everything that is available.
We need to acquire a lock which can block us which in turn causes
the dbus request handling to block as well. Place the request on
the work queue instead.
Our expectation was that when using the lvm shell that when the lvm prompt
was read from stdout, that all other ouput had been written and flushed.
However, this doesn't appear to be the case. Add extra read passes to
retrieve delayed report data.