In some cases creating an LVM2 Physical Volume on top of a DMRaid array
reports no usage information and this partition warning:
Unable to read the contents of this file system!
Because of this some operations may be unavailable.
The cause might be a missing software package.
The following list of software packages is required for lvm2
pv file system support: lvm2.
For example on Ubuntu 14.04 LTS (with GParted built with
--enable-libparted-dmraid) create an LVM2 PV in a DMRaid array
partition. GParted uses this command:
# lvm pvcreate -M 2 /dev/mapper/isw_bacdehijbd_MyArray0p2
But LVM reports the PV having a different name:
# lvm pvs
PV VG Fmt Attr PSize PFree
/dev/disk/by-id/dm-name-isw_bacdehijbd_MyArray0p2 lvm2 a-- 1.00g 1.00g
This alternate name is loaded into the LVM2_PV_Info module cache. Hence
when GParted queries partition /dev/mapper/isw_bacdehijbd_MyArray0p2 it
has no PV information against that name and reports unknown usage.
However they are actually the same block special device; major 252,
minor 2:
# ls -l /dev/mapper/isw_bacdehijbd_MyArray0p2
brw-rw---- 1 root disk 252, 2 Jul 2 11:09 /dev/mapper/isw_bacdehijbd_MyArray0p2
# ls -l /dev/disk/by-id/dm-name-isw_bacdehijbd_MyArray0p2
lrwxrwxrwx 1 root root 10 Jul 2 11:09 /dev/disk/by-id/dm-name-isw_bacdehijbd_MyArray0p2 -> ../../dm-2
# ls -l /dev/dm-2
brw-rw---- 1 root disk 252, 2 Jul 2 11:09 /dev/dm-2
To determine if two names refer to the same block special device their
major, minor numbers need to be compared, instead of string comparing
their names.
Implement class BlockSpecial which encapsulates the name and major,
minor numbers for a block special device. Also performs comparison as
needed. See bug 767842 comments 4 and 5 for further investigation and
decision for choosing to implement a class.
Replace name strings in the LVM2_PV_Info module with BlockSpecial
objects performing correct block special device comparison.
Bug 767842 - File system usage missing when tools report alternate block
device names
Write a generic progress bar class. Has the following features:
* Has separate progress and target numbers, rather than a single
completion fraction, to enable the the next feature.
* Optionally generates text reporting the amount of data copied using
the progress and target numbers like this:
"1.00 MiB of 16.00 MiB copied"
* After running for 5 seconds, also add estimated remaining time.
(Waits to allow the data copying rate to settle down a little before
estimating the remaining time). Looks like this:
"1.00 MiB of 16.00 MiB copied (00:01:59) remaining)"
The ProgressBar class is not driving the visual progress bar yet. It
has just been added into the internal block copy algorithm and generates
debug messages showing the progress bar is operating correctly.
Debugging looks like this:
DEBUG: ProgressBar::start(target=2.0636e+09, text_mode=PROGRESSBAR_TEXT_COPY_BYTES)
DEBUG: ProgressBar::update(progress=1.30023e+08) m_fraction=0.0630081 m_text="124.00 MiB of 1.92 GiB copied"
DEBUG: ProgressBar::update(progress=2.67387e+08) m_fraction=0.129573 m_text="255.00 MiB of 1.92 GiB copied"
DEBUG: ProgressBar::update(progress=4.0475e+08) m_fraction=0.196138 m_text="386.00 MiB of 1.92 GiB copied"
...
DEBUG: ProgressBar::update(progress=1.13351e+09) m_fraction=0.549289 m_text="1.06 GiB of 1.92 GiB copied (00:00:04 remaining)"
DEBUG: ProgressBar::update(progress=1.26249e+09) m_fraction=0.611789 m_text="1.18 GiB of 1.92 GiB copied (00:00:04 remaining)"
DEBUG: ProgressBar::update(progress=1.39041e+09) m_fraction=0.67378 m_text="1.29 GiB of 1.92 GiB copied (00:00:03 remaining)"
...
DEBUG: ProgressBar::update(progress=1.97552e+09) m_fraction=0.957317 m_text="1.84 GiB of 1.92 GiB copied (00:00:00 remaining)"
DEBUG: ProgressBar::update(progress=2.0636e+09) m_fraction=1 m_text="1.92 GiB of 1.92 GiB copied"
DEBUG: ProgressBar::stop()
Bug 760709 - Add progress bars to XFS and EXT2/3/4 file system specific
copy methods
Absolute minimum implementation of a PartitionLUKS class which can be
constructed, polymorphically copied and destroyed. Contains an
"encrypted" member of type Partition to represent the encrypted file
system within the LUKS format.
Create PartitionLUKS objects instead of base Partition objects when a
LUKS formatted partition is found. Only the base Partition object
member values have been populated, and the "encrypted" member remains
blank at this point.
Bug 760080 - Implement read-only LUKS support
Provide a minimal implementation of a luks file system class which only
does busy detection.
NOTE:
For now, read-only LUKS support, a LUKS partition will be busy when a
dm-crypt mapping exists. Later when read-write LUKS support is added
GParted will need to look at the busy status of the encrypted file
system within the open LUKS partition and map LUKS partition busy status
to encryption being open or closed.
Bug 760080 - Implement read-only LUKS support
Load basic details of active Device-mapper encryption mappings from the
kernel. Use dmsetup active targets.
# cryptsetup luksFormat /dev/sdb5
# cryptsetup luksFormat /dev/sdb6
# cryptsetup luksOpen /dev/sdb6 sdb6_crypt
# ls -l /dev/mapper/sdb6_crypt /dev/dm-0
lrwxrwxrwx. 1 root root 7 Nov 15 09:03 /dev/mapper/sdb6_crypt -> ../dm-0
brw-rw----. 1 root disk 253, 0 Nov 15 09:03 /dev/dm-0
# ls -l /dev/sdb6
brw-rw----. 1 root disk 8, 22 Nov 15 09:02 /dev/sdb6
# dmsetup table --target crypt
sdb6_crypt: 0 1044480 crypt aes-cbc-essiv:sha256 0000000000000000000000000000000000000000000000000000000000000000 0 8:22 4096
So far just load the mapping name and underlying block device reference
(path or major, minor pair).
Note that all supported kernels appear to report the underlying block
device as major, minor pair in the dmsetup output. Underlying block
device paths are added to the cache when found during a search to avoid
stat(2) call on subsequent searches for the same path.
Prints debugging to show results, like this:
# ./gpartedbin
======================
libparted : 2.4
======================
DEBUG: /dev/sdb5: LUKS closed
DEBUG: /dev/sdb6: LUKS open mapping /dev/mapper/sdb6_crypt
Bug 760080 - Implement read-only LUKS support
The PartitionVector class is now internally using pointers to Partition
objects and taking on management of their lifetimes. It therefore has
to implement the Big 3: destructor, copy constructor and copy assignment
operator [1][2]. This is because the implicitly-defined copy
constructor and assignment operator perform memberwise "shallow copying"
and the destructor does nothing. This not correct for classes which
contain non-class types such as raw pointers.
The semantics of the interface still copies each Partition object into
the PartitionVector when they are added with push_back() and insert().
Note that a PartitionVector object is explicitly copy assigned in
Win_GParted::Refresh_Visual(). They are also implicitly copied when
(1) the implementing vector is resized larger to allow it to hold more
pointers to Partition objects than it previously had capacity for; and
(2) a Partition object is copied including the logicals PartitionVector
member.
[1] The rule of three/five/zero
http://en.cppreference.com/w/cpp/language/rule_of_three
[2] Rule of Three
https://en.wikipedia.org/wiki/Rule_of_three_%28C%2B%2B_programming%29
Bug 759726 - Implement Partition object polymorphism
Mike Fleetwood