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lvm2/tools/polldaemon.c
David Teigland ba7ff96faf improve reading and repairing vg metadata
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- keep track of outdated PVs in lvmcache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.)
2019-06-07 15:54:04 -05:00

692 lines
18 KiB
C

/*
* Copyright (C) 2003-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2015 Red Hat, Inc. All rights reserved.
*
* This file is part of LVM2.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "tools.h"
#include "lib/lvmpolld/polldaemon.h"
#include "lvm2cmdline.h"
#include "lib/lvmpolld/lvmpolld-client.h"
#include <time.h>
#define WAIT_AT_LEAST_NANOSECS 100000
progress_t poll_mirror_progress(struct cmd_context *cmd,
struct logical_volume *lv, const char *name,
struct daemon_parms *parms)
{
dm_percent_t segment_percent = DM_PERCENT_0, overall_percent = DM_PERCENT_0;
uint32_t event_nr = 0;
if (!lv_is_mirrored(lv) ||
!lv_mirror_percent(cmd, lv, !parms->interval, &segment_percent,
&event_nr) ||
(segment_percent == DM_PERCENT_INVALID)) {
log_error("ABORTING: Mirror percentage check failed.");
return PROGRESS_CHECK_FAILED;
}
overall_percent = copy_percent(lv);
if (parms->progress_display)
log_print_unless_silent("%s: %s: %s%%", name, parms->progress_title,
display_percent(cmd, overall_percent));
else
log_verbose("%s: %s: %s%%", name, parms->progress_title,
display_percent(cmd, overall_percent));
if (segment_percent != DM_PERCENT_100)
return PROGRESS_UNFINISHED;
if (overall_percent == DM_PERCENT_100)
return PROGRESS_FINISHED_ALL;
return PROGRESS_FINISHED_SEGMENT;
}
static int _check_lv_status(struct cmd_context *cmd,
struct volume_group *vg,
struct logical_volume *lv,
const char *name, struct daemon_parms *parms,
int *finished)
{
struct dm_list *lvs_changed;
progress_t progress;
/* By default, caller should not retry */
*finished = 1;
if (parms->aborting) {
if (!(lvs_changed = lvs_using_lv(cmd, vg, lv))) {
log_error("Failed to generate list of copied LVs: "
"can't abort.");
return 0;
}
if (!parms->poll_fns->finish_copy(cmd, vg, lv, lvs_changed))
return_0;
return 1;
}
progress = parms->poll_fns->poll_progress(cmd, lv, name, parms);
fflush(stdout);
if (progress == PROGRESS_CHECK_FAILED)
return_0;
if (progress == PROGRESS_UNFINISHED) {
/* The only case the caller *should* try again later */
*finished = 0;
return 1;
}
if (!(lvs_changed = lvs_using_lv(cmd, vg, lv))) {
log_error("ABORTING: Failed to generate list of copied LVs");
return 0;
}
/* Finished? Or progress to next segment? */
if (progress == PROGRESS_FINISHED_ALL) {
if (!parms->poll_fns->finish_copy(cmd, vg, lv, lvs_changed))
return_0;
} else {
if (parms->poll_fns->update_metadata &&
!parms->poll_fns->update_metadata(cmd, vg, lv, lvs_changed, 0)) {
log_error("ABORTING: Segment progression failed.");
parms->poll_fns->finish_copy(cmd, vg, lv, lvs_changed);
return 0;
}
*finished = 0; /* Another segment */
}
return 1;
}
static void _nanosleep(unsigned secs, unsigned allow_zero_time)
{
struct timespec wtime = {
.tv_sec = secs,
};
if (!secs && !allow_zero_time)
wtime.tv_nsec = WAIT_AT_LEAST_NANOSECS;
while (!nanosleep(&wtime, &wtime) && errno == EINTR) {}
}
static void _sleep_and_rescan_devices(struct cmd_context *cmd, struct daemon_parms *parms)
{
if (parms->interval && !parms->aborting) {
/*
* FIXME: do we really need to drop everything and then rescan
* everything between each iteration? What change exactly does
* each iteration check for, and does seeing that require
* rescanning everything?
*/
lvmcache_destroy(cmd, 1, 0);
label_scan_destroy(cmd);
_nanosleep(parms->interval, 1);
lvmcache_label_scan(cmd);
}
}
int wait_for_single_lv(struct cmd_context *cmd, struct poll_operation_id *id,
struct daemon_parms *parms)
{
struct volume_group *vg = NULL;
struct logical_volume *lv;
int finished = 0;
uint32_t lockd_state = 0;
uint32_t error_flags = 0;
int ret;
if (!parms->wait_before_testing)
lvmcache_label_scan(cmd);
/* Poll for completion */
while (!finished) {
if (parms->wait_before_testing)
_sleep_and_rescan_devices(cmd, parms);
/*
* An ex VG lock is needed because the check can call finish_copy
* which writes the VG.
*/
if (!lockd_vg(cmd, id->vg_name, "ex", 0, &lockd_state)) {
log_error("ABORTING: Can't lock VG for %s.", id->display_name);
return 0;
}
/* Locks the (possibly renamed) VG again */
vg = vg_read(cmd, id->vg_name, NULL, READ_FOR_UPDATE, lockd_state, &error_flags, NULL);
if (!vg) {
/* What more could we do here? */
log_error("ABORTING: Can't reread VG for %s error flags %x.", id->display_name, error_flags);
ret = 0;
goto out;
}
lv = find_lv(vg, id->lv_name);
if (lv && id->uuid && strcmp(id->uuid, (char *)&lv->lvid))
lv = NULL;
if (lv && parms->lv_type && !(lv->status & parms->lv_type))
lv = NULL;
if (!lv) {
if (parms->lv_type == PVMOVE)
log_print_unless_silent("%s: No pvmove in progress - already finished or aborted.",
id->display_name);
else
log_print_unless_silent("Can't find LV in %s for %s.",
vg->name, id->display_name);
ret = 1;
goto out;
}
/*
* If the LV is not active locally, the kernel cannot be
* queried for its status. We must exit in this case.
*/
if (!lv_is_active(lv)) {
log_print_unless_silent("%s: Interrupted: No longer active.", id->display_name);
ret = 1;
goto out;
}
if (!_check_lv_status(cmd, vg, lv, id->display_name, parms, &finished)) {
ret = 0;
goto_out;
}
unlock_and_release_vg(cmd, vg, vg->name);
if (!lockd_vg(cmd, id->vg_name, "un", 0, &lockd_state))
stack;
/*
* FIXME Sleeping after testing, while preferred, also works around
* unreliable "finished" state checking in _percent_run. If the
* above _check_lv_status is deferred until after the first sleep it
* may be that a polldaemon will run without ever completing.
*
* This happens when one snapshot-merge polldaemon is racing with
* another (polling the same LV). The first to see the LV status
* reach the "finished" state will alter the LV that the other
* polldaemon(s) are polling. These other polldaemon(s) can then
* continue polling an LV that doesn't have a "status".
*/
if (!parms->wait_before_testing && !finished)
_sleep_and_rescan_devices(cmd, parms);
}
return 1;
out:
if (vg)
unlock_and_release_vg(cmd, vg, vg->name);
if (!lockd_vg(cmd, id->vg_name, "un", 0, &lockd_state))
stack;
return ret;
}
struct poll_id_list {
struct dm_list list;
struct poll_operation_id *id;
};
static struct poll_operation_id *_copy_poll_operation_id(struct dm_pool *mem,
const struct poll_operation_id *id)
{
struct poll_operation_id *copy;
if (!id || !id->vg_name || !id->lv_name || !id->display_name || !id->uuid) {
log_error(INTERNAL_ERROR "Wrong params for _copy_poll_operation_id.");
return NULL;
}
if (!(copy = dm_pool_alloc(mem, sizeof(*copy)))) {
log_error("Poll operation ID allocation failed.");
return NULL;
}
if (!(copy->display_name = dm_pool_strdup(mem, id->display_name)) ||
!(copy->lv_name = dm_pool_strdup(mem, id->lv_name)) ||
!(copy->vg_name = dm_pool_strdup(mem, id->vg_name)) ||
!(copy->uuid = dm_pool_strdup(mem, id->uuid))) {
log_error("Failed to copy one or more poll_operation_id members.");
dm_pool_free(mem, copy);
return NULL;
}
return copy;
}
static struct poll_id_list* _poll_id_list_create(struct dm_pool *mem,
const struct poll_operation_id *id)
{
struct poll_id_list *idl = (struct poll_id_list *) dm_pool_alloc(mem, sizeof(struct poll_id_list));
if (!idl) {
log_error("Poll ID list allocation failed.");
return NULL;
}
if (!(idl->id = _copy_poll_operation_id(mem, id))) {
dm_pool_free(mem, idl);
return NULL;
}
return idl;
}
static int _poll_vg(struct cmd_context *cmd, const char *vgname,
struct volume_group *vg, struct processing_handle *handle)
{
struct daemon_parms *parms;
struct lv_list *lvl;
struct dm_list idls;
struct poll_id_list *idl;
struct poll_operation_id id;
struct logical_volume *lv;
int finished;
if (!handle || !(parms = (struct daemon_parms *) handle->custom_handle)) {
log_error(INTERNAL_ERROR "Handle is undefined.");
return ECMD_FAILED;
}
dm_list_init(&idls);
/*
* first iterate all LVs in a VG and collect LVs suitable
* for polling (or an abort) which takes place below
*/
dm_list_iterate_items(lvl, &vg->lvs) {
lv = lvl->lv;
if (!(lv->status & parms->lv_type))
continue;
id.display_name = parms->poll_fns->get_copy_name_from_lv(lv);
if (!id.display_name && !parms->aborting)
continue;
if (!id.display_name) {
log_error("Device name for LV %s not found in metadata. "
"(unfinished pvmove mirror removal?)", display_lvname(lv));
goto err;
}
/* FIXME Need to do the activation from _set_up_pvmove here
* if it's not running and we're not aborting. */
if (!lv_is_active(lv)) {
log_print_unless_silent("%s: Skipping inactive LV. Try lvchange or vgchange.", id.display_name);
continue;
}
id.lv_name = lv->name;
id.vg_name = vg->name;
id.uuid = lv->lvid.s;
idl = _poll_id_list_create(cmd->mem, &id);
if (!idl) {
log_error("Failed to create poll_id_list.");
goto err;
}
dm_list_add(&idls, &idl->list);
}
/* perform the poll operation on LVs collected in previous cycle */
dm_list_iterate_items(idl, &idls) {
if (!(lv = find_lv(vg, idl->id->lv_name)))
continue;
if (idl->id->uuid && strcmp(idl->id->uuid, (char *)&lv->lvid))
continue;
if (parms->lv_type && !(lv->status & parms->lv_type))
continue;
if (_check_lv_status(cmd, vg, lv, idl->id->display_name, parms, &finished) && !finished)
parms->outstanding_count++;
}
err:
if (!dm_list_empty(&idls))
dm_pool_free(cmd->mem, dm_list_item(dm_list_first(&idls), struct poll_id_list));
return ECMD_PROCESSED;
}
static void _poll_for_all_vgs(struct cmd_context *cmd,
struct processing_handle *handle)
{
struct daemon_parms *parms = (struct daemon_parms *) handle->custom_handle;
while (1) {
parms->outstanding_count = 0;
process_each_vg(cmd, 0, NULL, NULL, NULL, READ_FOR_UPDATE, 0, handle, _poll_vg);
lock_global(cmd, "un");
if (!parms->outstanding_count)
break;
_nanosleep(parms->interval, 1);
}
}
#ifdef LVMPOLLD_SUPPORT
typedef struct {
struct daemon_parms *parms;
struct dm_list idls;
} lvmpolld_parms_t;
static int _report_progress(struct cmd_context *cmd, struct poll_operation_id *id,
struct daemon_parms *parms)
{
struct volume_group *vg;
struct logical_volume *lv;
uint32_t lockd_state = 0;
uint32_t error_flags = 0;
int ret;
/*
* It's reasonable to expect a lockd_vg("sh") here, but it should not
* actually be needed, because we only report the progress on the same
* host where the pvmove/lvconvert is happening. No VG lock is needed
* to protect anything here (we're just reading the VG), and no VG lock
* is needed to force a VG read from disk to get changes from other
* hosts, because the only change to the VG we're interested in is the
* change done locally.
*/
vg = vg_read(cmd, id->vg_name, NULL, 0, lockd_state, &error_flags, NULL);
if (!vg) {
log_error("Can't reread VG for %s error flags %x", id->display_name, error_flags);
ret = 0;
goto out_ret;
}
lv = find_lv(vg, id->lv_name);
if (lv && id->uuid && strcmp(id->uuid, (char *)&lv->lvid))
lv = NULL;
/*
* CONVERTING is set only during mirror upconversion but we may need to
* read LV's progress info even when it's not converting (linear->mirror)
*/
if (lv && (parms->lv_type ^ CONVERTING) && !(lv->status & parms->lv_type))
lv = NULL;
if (!lv) {
if (parms->lv_type == PVMOVE)
log_verbose("%s: No pvmove in progress - already finished or aborted.",
id->display_name);
else
log_verbose("Can't find LV in %s for %s. Already finished or removed.",
vg->name, id->display_name);
ret = 1;
goto out;
}
if (!lv_is_active(lv)) {
log_verbose("%s: Interrupted: No longer active.", id->display_name);
ret = 1;
goto out;
}
if (parms->poll_fns->poll_progress(cmd, lv, id->display_name, parms) == PROGRESS_CHECK_FAILED) {
ret = 0;
goto out;
}
fflush(stdout);
ret = 1;
out:
unlock_and_release_vg(cmd, vg, vg->name);
out_ret:
return ret;
}
static int _lvmpolld_init_poll_vg(struct cmd_context *cmd, const char *vgname,
struct volume_group *vg, struct processing_handle *handle)
{
int r;
struct lv_list *lvl;
struct logical_volume *lv;
struct poll_id_list *idl;
struct poll_operation_id id;
lvmpolld_parms_t *lpdp = (lvmpolld_parms_t *) handle->custom_handle;
dm_list_iterate_items(lvl, &vg->lvs) {
lv = lvl->lv;
if (!(lv->status & lpdp->parms->lv_type))
continue;
id.display_name = lpdp->parms->poll_fns->get_copy_name_from_lv(lv);
if (!id.display_name && !lpdp->parms->aborting)
continue;
id.vg_name = lv->vg->name;
id.lv_name = lv->name;
if (!*lv->lvid.s) {
log_print_unless_silent("Missing LV uuid within: %s/%s", id.vg_name, id.lv_name);
continue;
}
id.uuid = lv->lvid.s;
r = lvmpolld_poll_init(cmd, &id, lpdp->parms);
if (r && !lpdp->parms->background) {
if (!(idl = _poll_id_list_create(cmd->mem, &id)))
return ECMD_FAILED;
dm_list_add(&lpdp->idls, &idl->list);
}
}
return ECMD_PROCESSED;
}
static void _lvmpolld_poll_for_all_vgs(struct cmd_context *cmd,
struct daemon_parms *parms,
struct processing_handle *handle)
{
int r;
struct dm_list *first;
struct poll_id_list *idl, *tlv;
unsigned finished;
lvmpolld_parms_t lpdp = {
.parms = parms
};
dm_list_init(&lpdp.idls);
handle->custom_handle = &lpdp;
process_each_vg(cmd, 0, NULL, NULL, NULL, 0, 0, handle, _lvmpolld_init_poll_vg);
first = dm_list_first(&lpdp.idls);
while (!dm_list_empty(&lpdp.idls)) {
dm_list_iterate_items_safe(idl, tlv, &lpdp.idls) {
r = lvmpolld_request_info(idl->id, lpdp.parms,
&finished);
if (!r || finished)
dm_list_del(&idl->list);
else if (!parms->aborting)
_report_progress(cmd, idl->id, lpdp.parms);
}
_nanosleep(lpdp.parms->interval, 0);
}
if (first)
dm_pool_free(cmd->mem, dm_list_item(first, struct poll_id_list));
}
static int _lvmpoll_daemon(struct cmd_context *cmd, struct poll_operation_id *id,
struct daemon_parms *parms)
{
int r;
struct processing_handle *handle = NULL;
unsigned finished = 0;
if (parms->aborting)
parms->interval = 0;
if (id) {
r = lvmpolld_poll_init(cmd, id, parms);
if (r && !parms->background) {
while (1) {
if (!(r = lvmpolld_request_info(id, parms, &finished)) ||
finished ||
(!parms->aborting && !(r = _report_progress(cmd, id, parms))))
break;
_nanosleep(parms->interval, 0);
}
}
return r ? ECMD_PROCESSED : ECMD_FAILED;
}
/* process all in-flight operations */
if (!(handle = init_processing_handle(cmd, NULL))) {
log_error("Failed to initialize processing handle.");
return ECMD_FAILED;
}
_lvmpolld_poll_for_all_vgs(cmd, parms, handle);
destroy_processing_handle(cmd, handle);
return ECMD_PROCESSED;
}
#else
# define _lvmpoll_daemon(cmd, id, parms) (ECMD_FAILED)
#endif /* LVMPOLLD_SUPPORT */
/*
* Only allow *one* return from poll_daemon() (the parent).
* If there is a child it must exit (ignoring the memory leak messages).
* - 'background' is advisory so a child polldaemon may not be used even
* if it was requested.
*/
static int _poll_daemon(struct cmd_context *cmd, struct poll_operation_id *id,
struct daemon_parms *parms)
{
struct processing_handle *handle = NULL;
int daemon_mode = 0;
int ret = ECMD_PROCESSED;
if (parms->background) {
daemon_mode = become_daemon(cmd, 0);
if (daemon_mode == 0)
return ECMD_PROCESSED; /* Parent */
if (daemon_mode == 1)
parms->progress_display = 0; /* Child */
/* FIXME Use wait_event (i.e. interval = 0) and */
/* fork one daemon per copy? */
}
/*
* Process one specific task or all incomplete tasks?
*/
/* clear lvmcache/bcache/fds from the parent */
lvmcache_destroy(cmd, 1, 0);
label_scan_destroy(cmd);
if (id) {
if (!wait_for_single_lv(cmd, id, parms)) {
stack;
ret = ECMD_FAILED;
}
} else {
if (!parms->interval)
parms->interval = find_config_tree_int(cmd, activation_polling_interval_CFG, NULL);
if (!(handle = init_processing_handle(cmd, NULL))) {
log_error("Failed to initialize processing handle.");
ret = ECMD_FAILED;
} else {
handle->custom_handle = parms;
_poll_for_all_vgs(cmd, handle);
}
}
if (parms->background && daemon_mode == 1) {
destroy_processing_handle(cmd, handle);
/*
* child was successfully forked:
* background polldaemon must not return to the caller
* because it will redundantly continue performing the
* caller's task (that the parent already performed)
*/
/* FIXME Attempt proper cleanup */
_exit(lvm_return_code(ret));
}
destroy_processing_handle(cmd, handle);
return ret;
}
static int _daemon_parms_init(struct cmd_context *cmd, struct daemon_parms *parms,
unsigned background, struct poll_functions *poll_fns,
const char *progress_title, uint64_t lv_type)
{
sign_t interval_sign;
parms->aborting = arg_is_set(cmd, abort_ARG);
parms->background = background;
interval_sign = arg_sign_value(cmd, interval_ARG, SIGN_NONE);
if (interval_sign == SIGN_MINUS) {
log_error("Argument to --interval cannot be negative.");
return 0;
}
parms->interval = arg_uint_value(cmd, interval_ARG,
find_config_tree_int(cmd, activation_polling_interval_CFG, NULL));
parms->wait_before_testing = (interval_sign == SIGN_PLUS);
parms->progress_title = progress_title;
parms->lv_type = lv_type;
parms->poll_fns = poll_fns;
if (parms->interval && !parms->aborting)
log_verbose("Checking progress %s waiting every %u seconds.",
(parms->wait_before_testing ? "after" : "before"),
parms->interval);
parms->progress_display = parms->interval ? 1 : 0;
return 1;
}
int poll_daemon(struct cmd_context *cmd, unsigned background,
uint64_t lv_type, struct poll_functions *poll_fns,
const char *progress_title, struct poll_operation_id *id)
{
struct daemon_parms parms;
if (!_daemon_parms_init(cmd, &parms, background, poll_fns, progress_title, lv_type))
return_EINVALID_CMD_LINE;
if (lvmpolld_use())
return _lvmpoll_daemon(cmd, id, &parms);
/* classical polling allows only PMVOVE or 0 values */
parms.lv_type &= PVMOVE;
return _poll_daemon(cmd, id, &parms);
}