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Commit Graph

302 Commits

Author SHA1 Message Date
Peter Rajnoha
8fad9b9e5d dev: be safer when reading sysfs properties
Check if the value we read from sysfs is not blank and replace the '\n'
at the end only when needed ('\n' should usually be there for sysfs values,
but better check this).
2016-03-21 15:50:32 +01:00
Peter Rajnoha
03b0a78640 dev: detect mismatch between devices used and devices assumed for an LV
It's possible for an LVM LV to use a device during activation which
then differs from device which LVM assumes based on metadata later on.

For example, such device mismatch can occur if LVM doesn't have
complete view of devices during activation or if filters are
misbehaving or they're incorrectly set during activation.

This patch adds code that can detect this mismatch by creating
VG UUID and LV UUID index while scanning devices for device cache.

The VG UUID index maps VG UUID to a device list. Each device in the
list has a device layered above as a holder which is an LVM LV device
and for which we know the VG UUID (and similarly for LV UUID index).

We can acquire VG and LV UUID by reading /sys/block/<dm_dev_name>/dm/uuid.
So these indices represent the actual state of PV device use in
the system by LVs and then we compare that to what LVM assumes
based on metadata.

For example:

[0] fedora/~ # lsblk /dev/sdq /dev/sdr /dev/sds /dev/sdt
NAME         MAJ:MIN RM  SIZE RO TYPE  MOUNTPOINT
sdq           65:0    0  104M  0 disk
|-vg-lvol0   253:2    0  200M  0 lvm
`-mpath_dev1 253:3    0  104M  0 mpath
sdr           65:16   0  104M  0 disk
`-mpath_dev1 253:3    0  104M  0 mpath
sds           65:32   0  104M  0 disk
|-vg-lvol0   253:2    0  200M  0 lvm
`-mpath_dev2 253:4    0  104M  0 mpath
sdt           65:48   0  104M  0 disk
`-mpath_dev2 253:4    0  104M  0 mpath

In this case the vg-lvol0 is mapped onto sdq and sds becauset this is
what was available and seen during activation. Then later on, sdr and
sdt appeared and mpath devices were created out of sdq+sdr (mpath_dev1)
and sds+sdt (mpath_dev2). Now, LVM assumes (correctly) that mpath_dev1
and mpath_dev2 are the PVs that should be used, not the mpath
components (sdq/sdr, sds/sdt).

[0] fedora/~ # pvs
  Found duplicate PV xSUix1GJ2SK82ACFuKzFLAQi8xMfFxnO: using /dev/mapper/mpath_dev1 not /dev/sdq
  Using duplicate PV /dev/mapper/mpath_dev1 from subsystem DM, replacing /dev/sdq
  Found duplicate PV MvHyMVabtSqr33AbkUrobq1LjP8oiTRm: using /dev/mapper/mpath_dev2 not /dev/sds
  Using duplicate PV /dev/mapper/mpath_dev2 from subsystem DM, ignoring /dev/sds
  WARNING: Device mismatch detected for vg/lvol0 which is accessing /dev/sdq, /dev/sds instead of /dev/mapper/mpath_dev1, /dev/mapper/mpath_dev2.
  PV                     VG     Fmt  Attr PSize   PFree
  /dev/mapper/mpath_dev1 vg     lvm2 a--  100.00m      0
  /dev/mapper/mpath_dev2 vg     lvm2 a--  100.00m      0
2016-03-21 11:40:40 +01:00
Peter Rajnoha
65d9f742f8 device: add DEV_OPEN_FAILURE flag
DEV_OPEN_FAILURE flag is set if the most recent "open" for a device
failed and it's unset if any subsequent "open" succeeds.
2016-03-21 11:06:05 +01:00
Alasdair G Kergon
2159a1429d pre-release 2016-03-11 00:19:16 +00:00
Zdenek Kabelac
5aade9c402 topology: handle reported sizes smaller then sector
Recent kernel (4.4) start to report values smaller then sector size
(but in reporting size for SSD which support data zeroing on discard).

For now log warning and assume it really means 1 sector.

Addressing RHBZ:
https://bugzilla.redhat.com/show_bug.cgi?id=1313377
2016-03-10 18:38:54 +01:00
David Teigland
57cd94b9e3 pvs: replace 'unknown device' with [unknown]
A config setting can restore the old string.
2016-03-01 11:12:03 -06:00
Zdenek Kabelac
9267e0c5e7 cleanup: use braces around macro params 2016-02-23 21:40:17 +01:00
Zdenek Kabelac
c0b836e316 gcc: logical-op warning go away
Don't be too much inventive and shutdown gcc6 warning:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602
2016-02-23 14:41:24 +01:00
Peter Rajnoha
ec43f55445 filters: partitioned: fix partition table filter with external_device_info_source="udev" and blkid<2.20
Non-dm devices have ID_PART_TABLE_TYPE variable exported in
udev db from blkid scan for *both* whole devices and partitions.
We used ID_PART_ENTRY_DISK in addition to decide whether this
is the whole device or partition and then we filtered out only
whole devices where the partition table really is.

However, ID_PART_ENTRY_DISK was added in blkid 2.20 so we need
to use a different set of variables to decide on whole devices
and partitions on systems where older blkid is still used.

Now, we use ID_PART_TABLE_TYPE to detect that there's something
related to partitioning with this device and we use DEVTYPE variable
instead to decide between whole device (DEVTYPE="disk") and partition
(DEVTYPE="partition").

For dm devices it's simpler, we have ID_PART_TABLE_TYPE variable\
set in udev db for whole devices. It's not set for partitions,
hence we don't need more variable in addition to make the decision
on whole device vs. partition (dm devices do not have regular
partitions, hence DEVTYPE can't be used anyway, it's always set
to "disk" for whole disks and partitions).
2016-02-02 13:28:11 +01:00
Peter Rajnoha
d090d6574e device: also cache device size
Add "size" and "size_seqno" to struct device to cache device's size
and also to control its lifetime - the cached value is valid as long
as the global _dev_size_seqno is equal to the device's size_seqno,
otherwise we need to get the size again and cache the new value.

This patch also adds new dev_size_seqno_inc() fn for the appropriate
parts of the code to increment current global value of _dev_size_seqno
and hence to cause all currently cached values for device sizes to
be invalidated.

The device size is now cached because we're planning to reuse this
information for further checks and we want to avoid checking it more
than necessary to save resources.
2016-01-22 14:13:34 +01:00
Zdenek Kabelac
fcbef05aae doc: change fsf address
Hmm rpmlint suggest fsf is using a different address these days,
so lets keep it up-to-date
2016-01-21 12:11:37 +01:00
David Teigland
92e1422707 process_each_pv: do full scan earlier to find new devices
Before commit c1f246fedf,
_get_all_devices() did a full device scan before
get_vgnameids() was called.  The full scan in
_get_all_devices() is from calling dev_iter_create(f, 1).
The '1' arg forces a full scan.

By doing a full scan in _get_all_devices(), new devices
were added to dev-cache before get_vgnameids() began
scanning labels.  So, labels would be read from new devices.
(e.g. by the first 'pvs' command after the new device appeared.)

After that commit, _get_all_devices() was called
after get_vgnameids() was finished scanning labels.
So, new devices would be missed while scanning labels.
When _get_all_devices() saw the new devices (after
labels were scanned), those devices were added to
the .cache file.  This meant that the second 'pvs'
command would see the devices because they would be
in .cache.

Now, the full device scan is factored out of
_get_all_devices() and called by itself at the
start of the command so that new devices will
be known before get_vgnameids() scans labels.
2015-12-14 10:02:29 -06:00
Zdenek Kabelac
dccbc3b621 cleanup: simplify dev_cache_exit
Just set whole _cache struct into unitialized state just
like with lib init start usage.
Lists are initialized with dev_cache_init().
2015-11-16 01:16:11 +01:00
Zdenek Kabelac
5a4676fea9 cleanup: add _free on error path
Just like with failing allocation above also _free(dev).

TODO: rework this to always use mempool and drop unneeded
comlexity we have in this function.
2015-11-16 01:16:11 +01:00
Peter Rajnoha
b8779e706e configure: check for udev_device_get_is_initialized is available
The udev_device_get_is_initialized is available since libudev version
165. Older versions are still used somewhere (e.g. RHEL6). So better
check for this fn and use it only if it's available.
2015-11-11 15:15:50 +01:00
Peter Rajnoha
f82e0210b7 dev-ext: issue error if external_device_info_source=udev and udev db record incomplete
Udev db records are marked as not initialized (incomplete) on timeout.
Issue an error message whenever LVM finds such records so users are
aware that something's going wrong with udev db.

This is important in case we use devices/external_device_info_source="udev"
where udev database records are used to do various filtering decisions.

For example:

udev log of timed out worker:

Nov 11 13:02:25 raw.virt systemd-udevd[607]: seq 1997 '/devices/virtual/block/dm-2' is taking a long time
Nov 11 13:04:25 raw.virt systemd-udevd[607]: seq 1997 '/devices/virtual/block/dm-2' killed
Nov 11 13:04:25 raw.virt systemd-udevd[607]: worker [11221] terminated by signal 9 (Killed)
Nov 11 13:04:25 raw.virt systemd-udevd[607]: worker [11221] failed while handling '/devices/virtual/block/dm-2'
...

LVM also issues error message visibly if incomplete udev db record is found,
devices/external_device_info_source="udev" is set:

$ pvs
  Udev database has incomplete information about device /dev/dm-2.
  Failed to get external handle for device /dev/dm-2 [udev].
  ...
2015-11-11 13:14:07 +01:00
Zdenek Kabelac
e262d5e596 cleanup: keep using enum typedef
Using enum instead of unsigned.
2015-11-09 10:22:52 +01:00
Zdenek Kabelac
fa1d730847 dev-type: fix TOCTOU order
Doing 'stat' checking first and later opening is racy.
And since we do not really care about any 'status' info
here and we read 'sysfs' here - just drop whole 'stat()'
call and directly handle error from failing 'fopen()'.
2015-11-09 10:19:20 +01:00
Alasdair G Kergon
65ec00ce20 device: Tidy DASD CDL format detection code. 2015-10-27 15:27:52 +00:00
Lidong Zhong
729f489009 pvcreate: don't support unpartitioned DASD devices with CDL formatted
The former patch(dab3ebce4c) is a little bit strict. For example, it is
OK to create PV on unpartitioned DASD devices with LDL formatted. So
after lvm version containing the patch, LVs created on those devices
could not be found.

Signed-off-by: Lidong Zhong <lzhong@suse.com>
2015-10-27 11:42:47 +01:00
Peter Rajnoha
5ac81657e5 wiping: make libblkid detect all copies of the same signature if use_blkid_wiping=1
Some signatures are spread around the disk in several copies, mainly for
backup. Make libblkid to detect these extra copies - there was missing
"blkid_probe_step_back" fn call after successful wipe of previous signature
copy.

An example with FAT table which has copies:

$ mkfs.vfat /dev/sda1

Before this patch:

$ pvcreate /dev/sda1
WARNING: vfat signature detected on /dev/sda1 at offset 54. Wipe it? [y/n]: y
  Wiping vfat signature on /dev/sda1.
  Physical volume "/dev/sda1" successfully created

With this patch applied:

$ pvcreate /dev/sda1
WARNING: vfat signature detected on /dev/sda1 at offset 54. Wipe it? [y/n]: y
  Wiping vfat signature on /dev/sda1.
WARNING: vfat signature detected on /dev/sda1 at offset 0. Wipe it? [y/n]: y
  Wiping vfat signature on /dev/sda1.
WARNING: vfat signature detected on /dev/sda1 at offset 510. Wipe it? [y/n]: y
  Wiping vfat signature on /dev/sda1.
  Physical volume "/dev/sda1" successfully created
2015-10-13 12:22:09 +02:00
Peter Rajnoha
2081071bee wiping: warn if use_blkid_wiping=1 is set and LVM not compiled with blkid_wiping support 2015-09-22 11:11:26 +02:00
Peter Rajnoha
55c13f3de4 dev-cache: fix use of uninitialized device status if reading outdated .cache record
As part of fix that came with cf700151eb,
I forgot to add the check whether the result of stat was successful or
not. This bug caused uninitialized buffer to be used for entries
from .cache file which are no longer valid.

This bug may have caused these uninitialized values to be used further,
for example (see the unreal (2567,590944) representing major:minor
pair):

$ pvs
  /dev/abc: stat failed: No such file or directory
  Path /dev/abc no longer valid for device(2567,590944)
  PV               VG   Fmt  Attr PSize   PFree
  /dev/mapper/test      lvm2 ---  104.00m 104.00m
  /dev/vda2        rhel lvm2 a--    9.51g      0
2015-09-04 18:00:29 +02:00
Peter Rajnoha
d1d00fdeec dev-cache: append (major:minor) to debug messages about adding device or its alias to cache
device/dev-cache.c:350         /dev/sda: Added to device cache (8:0)
device/dev-cache.c:346         /dev/disk/by-id/lvm-pv-uuid-5nPovF-EWp4-vBwd-ylCJ-9Y0B-yzHQ-ek1li2: Aliased to /dev/sda in device cache (8:0)
...
2015-09-03 14:36:15 +02:00
Alasdair G Kergon
623b46a17d device: Don't try to close config file on failure.
$file: open failed: Permission denied
Failed to load config file $file
Attempt to close device '$file' which is not open.
2015-08-17 12:57:01 +01:00
Peter Rajnoha
cf700151eb cache: fix regression causing some PVs to bypass filters
This is a regression introduced by commit
6c0e44d5a2 which changed
the way dev_cache_get fn works - before this patch, when a
device was not found, it fired a full rescan to correct the
cache. However, the change coming with that commit missed
this full_rescan call, causing the lvmcache to still contain
info about PVs which should be filtered now.

Such situation may have happened by coincidence of using
old persistent cache (/etc/lvm/cache/.cache) which does not
reflect the actual state anymore, a device name/symlink which
now points to a device which should be filtered and a fact we
keep info about usable DM devices in .cache no matter what
the filter setting is.

This bug could be hidden though by changes introduced in
commit f1a000a477 as it
calls full_rescan earlier before this problem is hit.
But we need to fix this anyway for the dev_cache_get
to be correct if we happen to use the same code path
again somewhere sometime.

For example, simple reproducer was (before commit
1a000a477558e157532d5f2cd2f9c9139d4f87c):

- /dev/sda contains a PV header with UUID y5PzRD-RBAv-7sBx-V3SP-vDmy-DeSq-GUh65M

- lvm.conf: filter = [ "r|.*|" ]

- rm -f .cache (to start with clean state)

- dmsetup create test --table "0 8388608 linear /dev/sda 0" (8388608 is
  just the size of the /dev/sda device I use in the reproducer)

- pvs (this will create .cache file which contains
  "/dev/disk/by-id/lvm-pv-uuid-y5PzRD-RBAv-7sBx-V3SP-vDmy-DeSq-GUh65M"
  as well as "/dev/mapper/test" and the target node "/dev/dm-1" - all the
  usable DM mappings (and their symlinks) get into the .cache file even
  though the filter "is set to "ignore all" - we do this - so far it's OK)

- dmsetup remove test (so we end up with /dev/disk/by-id/lvm-pv-uuid-...
  pointing to the /dev/sda now since it's the underlying device
  containing the actual PV header)

- now calling "pvs" with such .cache file and we get:
$ pvs
  PV                                                                 VG  Fmt  Attr PSize PFree
  /dev/disk/by-id/lvm-pv-uuid-y5PzRD-RBAv-7sBx-V3SP-vDmy-DeSq-GUh65M vg  lvm2 a--  4.00g    0

Even though we have set filter = [ "r|.*|" ] in the lvm.conf file!
2015-07-29 10:19:12 +02:00
Peter Rajnoha
c3fddb0fbb wiping: add "Wiping skipped." for the message context to be complete 2015-07-21 11:00:43 +02:00
Peter Rajnoha
697fb353dc wiping: log_warn instead of log_error if blkid wipe ignored for a signature
Comply with the rules we have for log_error and log_warn...

$ pvcreate /dev/sda1
  Failed to get offset of the xfs_external_log signature on /dev/sda1.
  1 existing signature left on the device.
  Aborting pvcreate on /dev/sda1.

$ pvcreate /dev/sda1 --force
  WARNING: Failed to get offset of the xfs_external_log signature on /dev/sda1.
  Physical volume "/dev/sda1" successfully created
2015-07-21 10:34:04 +02:00
Peter Rajnoha
2a7c2539c6 wiping: ignore errors during detection if use_blkid_wiping=1 and --force is used
libblkid may return the list of signatures found, but it may not
provide offset and size for each signature detected. This may
happen in case signatures are mixed up or there are more, possibly
overlapping, signatures found.

Make lvm commands pass if such situation happens and we're using
--force (or any stronger force method).

For example:

$ pvcreate /dev/sda1
  Failed to get offset of the xfs_external_log signature on /dev/sda1.
  1 existing signature left on the device.
  Aborting pvcreate on /dev/sda1.

$ pvcreate --force /dev/sda1
  Failed to get offset of the xfs_external_log signature on /dev/sda1.
  Physical volume "/dev/sda1" successfully created
2015-07-21 09:54:20 +02:00
Peter Rajnoha
d947a815e8 config: make a difference between "not found" and "is empty" in log msg for devices/preferred_names
Replace misleading "not found" in the log message when
devices/preferred_names is set to empty array:

Really not found:
device/dev-cache.c:689   devices/preferred_names not found in config: using built-in preferences

Found, but empty:
config/config.c:1431   Setting devices/preferred_names to preferred_names = [ ]
device/dev-cache.c:689   devices/preferred_names is empty: using built-in preferences
2015-07-15 16:14:51 +02:00
Peter Rajnoha
3b6840e099 config: replace find_config_tree_node with find_config_tree_array where appropriate 2015-07-08 13:03:08 +02:00
Zdenek Kabelac
5232fd13f3 cleanup: cast minor to dev_t
Let the arithmetic run with a single dev_t type (Coverity).
2015-05-08 15:15:10 +02:00
David Teigland
beb229e1e8 devices: improve handling of duplicate PVs
Example:

/dev/loop0 and /dev/loop1 are duplicates,
created by copying one backing file to the
other.

'identity /dev/loopX' creates an identity
mapping for loopX named idmloopX, which
adds a duplicate for the named device.

The duplicate selection code for lvmetad is
incomplete, and lvmetad is disabled for this
example.

[~]# losetup -f loopfile0
[~]# pvs
  PV         VG           Fmt  Attr PSize   PFree
  /dev/loop0 foo          lvm2 a--  308.00m 296.00m

[~]# losetup -f loopfile1
[~]# pvs
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/loop1 not /dev/loop0
  Using duplicate PV /dev/loop1 which is more recent, replacing /dev/loop0
  PV         VG           Fmt  Attr PSize   PFree
  /dev/loop1 foo          lvm2 a--  308.00m 308.00m

[~]# ./identity /dev/loop0
[~]# pvs
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/loop1 not /dev/loop0
  Using duplicate PV /dev/loop1 without holders, replacing /dev/loop0
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/mapper/idmloop0 not /dev/loop1
  Using duplicate PV /dev/mapper/idmloop0 from subsystem DM, replacing /dev/loop1
  PV                   VG           Fmt  Attr PSize   PFree
  /dev/mapper/idmloop0 foo          lvm2 a--  308.00m 296.00m

[~]# ./identity /dev/loop1
[~]# pvs
  WARNING: duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV is being used from both devices /dev/loop0 and /dev/loop1
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/loop1 not /dev/loop0
  Using duplicate PV /dev/loop1 which is more recent, replacing /dev/loop0
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/mapper/idmloop0 not /dev/loop1
  Using duplicate PV /dev/mapper/idmloop0 from subsystem DM, replacing /dev/loop1
  Found duplicate PV LnSOEqzEYED3RvIOa5PZP2s7uyuBLmAV: using /dev/mapper/idmloop1 not /dev/mapper/idmloop0
  Using duplicate PV /dev/mapper/idmloop1 which is more recent, replacing /dev/mapper/idmloop0
  PV                   VG           Fmt  Attr PSize   PFree
  /dev/mapper/idmloop1 foo          lvm2 a--  308.00m 308.00m
2015-04-28 10:41:32 -05:00
Zdenek Kabelac
53ef14fca0 debug: log scanned value
Fix verbose print of scanned value for topology attribute.
Result is set afterwards in sectors.
2015-04-02 13:38:41 +02:00
Zdenek Kabelac
32a6c11877 pvscan: check sysfs dev entry before rescan
When pvscan --cache --major --minor command is issued from
udev REMOVE event, it basically resulted into a whole device
scan since the device was missing. So avoid such scan
and first check via /sysfs (when available) if such device actually
exists.
2015-03-18 16:19:58 +01:00
Zdenek Kabelac
6f68f4364b devices: avoid extra open() syscall
If the device is already opened by lvm's device cache,
avoid extra syscall opening devices for obtaining its size.
2015-03-06 13:17:39 +01:00
Zdenek Kabelac
4c184e9d6b cleanup: drop unused value assign
Dop unused value assignments.

Unknown is detected via other combination
(!linear && !striped).

Also change the log_error() message into a warning,
since the function is not really returning error,
but still keep the INTERNAL_ERROR.

Ret value is always set later.
2015-02-19 14:43:25 +01:00
Peter Rajnoha
69b1e32c8a wiping: blkid: do not count skipped signatures in final number of wipes
We exclude some signatures from being wiped when using blkid wiping.
These are signatures which we simply overwrite. For example, the
LVM2_member signature which denotes a PV - if we call pvcreate on
existing PV, we just overwrite the PV header, no need to wipe it.

Previously, we counted such signatures as if they were wiped
and they were counted in the final number of wiped signatures
that _wipe_known_signatures_with_blkid fn returned in the "wiped"
output arg. Then the code checking this output arg could be
mislead that wiping happened while no wiping took place in real
and we could fire some code uselessly based on this information
(e.g. refreshing filters/rescanning - see also
commit 6b4066585f).
2015-02-19 13:30:05 +01:00
Peter Rajnoha
6b4066585f filters: no need to refresh filters/rescan if no signature is wiped during pvcreate at all
Before, we refreshed filters and we did full rescan of devices if
we passed through wiping (wipe_known_signatures fn call). However,
this fn returns success even if no signatures were found and so
nothing was wiped. In this case, it's not necessary to do the
filter refresh/rescan of devices as nothing changed clearly.

This patch exports number of wiped signatures from all the
wiping functions below. The caller (_pvcreate_check) then checks
whether any wiping was done at all and if not, no refresh/rescan
is done, saving some time and resources.
2015-02-17 09:46:34 +01:00
Peter Rajnoha
28ba0450e9 cleanup: add dev-ext-udev-constants.h with constants/names of the properties/values used from udev db 2015-01-30 13:17:12 +01:00
Peter Rajnoha
787f6ce04a filter-partitioned: use new 'udev' device status source to get partition status
Partitioned devices are marked in udev db as:
  ID_PART_TABLE="<partition table type name>"
and at the same time they are *not* marked with:
  ID_PART_ENTRY_DISK="<parent disk major:minor>"

Where partition table type name is dos/gpt/... But checking the presence
of this variable is enough for LVM here - it just needs to know whether
there's a partition table or not, not interested in the actual type.
The same applies for parent disk major:minor.
2015-01-30 13:17:12 +01:00
Peter Rajnoha
590fbd8961 filter-md: use new 'udev' external device info source to get MD component status
MD components are marked in udev db as:
  ID_FS_TYPE="linux_raid_member"
2015-01-30 13:01:12 +01:00
Peter Rajnoha
fbfde21e7c device: add infrastructure to support external device info 2015-01-30 13:01:12 +01:00
Alasdair G Kergon
3e11d85c77 devices: DASD doesn't need to be stackable. 2015-01-23 20:32:31 +00:00
Alasdair G Kergon
dab3ebce4c devices: Do not support unpartitioned DASD. 2015-01-23 20:01:34 +00:00
Peter Rajnoha
99d895014d dev-type: filter out partitioned device-mapper devices as unsuitable for use as PVs
Normally, if there are partitions defined on top of device-mapper
device, there should be a device-mapper device created for each
partiton on top of the old one and once the underlying DM device
is used by another devices (partition mappings in this case),
it can't be used as a PV anymore.

However, sometimes, it may happen the partition mappings are
missing - either the partitioning tool is not creating them if
it does not contain full support for device-mapper devices or
the mappings were removed.

Better safe than sorry - check for partition header on DM devs
and filter them out as unsuitable for PVs in case the check is
positive. Whatever the user is doing, let's do our best to prevent
unwanted corruption (...by running pvcreate on top of such device
that would corrupt the partition header).
2015-01-12 14:10:44 +01:00
Zdenek Kabelac
88e944b5a3 cleanup: remove unused headers 2014-11-13 17:49:42 +01:00
Alasdair G Kergon
d1bcdd7338 device: Fix BLKSSZGET definition check. 2014-10-13 18:15:41 +01:00
Zdenek Kabelac
3cef6dd721 cleanup: drop duplicate const usage
const char == const char const.
2014-09-24 10:54:48 +02:00
Alasdair G Kergon
b9c16b7506 devices: Detect rotational devices.
Add dev_is_rotational() for future use by allocation code.
2014-09-16 00:44:25 +01:00