Add APIs that allow to dynamically register driver backends so that the
list of available drivers does not need to be known during compile time.

This will allow us to modularize the storage driver on runtime.

The file became a garbage dump for all kinds of utility functions over
time. Move them to a separate file so that the files can become a clean
interface for the storage backends.

The storage driver helper functions that deal with parted were put into
the disk backend code but are used commonly across.

https://bugzilla.redhat.com/show_bug.cgi?id=1346566

If libvirt_parthelper is erroneously told to append the partition
separator 'p' onto the generated output for a disk pool using device
mapper that has 'user_friendly_names' set to true, then the error
recovery path will fail to find volume resulting in the pool being
in an unusable state.

So, augment the documentation to provide the better hint that the
part_separator='yes' should be set when user_friendly_names are not
being used. Additionally, once we're in the error path where the
returned name doesn't match the expected partition name try to see
if the reason is because the 'p' was erroneosly added. If so alter
the about to be removed vol->target.path so that the DiskDeleteVol
code can find the partition that was created and remove it.

Commit id 'a48c674f' caused problems for systems without PARTED installed.

So move the PARTED probing code back to storage_backend_disk.c and create
a shim within storage_backend.c to call it if WITH_STORAGE_DISK is true;
otherwise, just return -1 with the error.

Rather than have the Disk code having to use PARTED to determine if
there's something on the device, let's use the virStorageBackendDeviceProbe.
and only fallback to the PARTED probing if the BLKID code isn't built in.

This will also provide a mechanism for the other current caller (File
System Backend) to utilize a PARTED parsing algorithm in the event that
BLKID isn't built in to at least see if *something* exists on the disk
before blindly trying to use. The PARTED error checking will not find
file system types, but if there is a partition table set on the device,
it will at least cause a failure.

Move virStorageBackendDiskValidLabel and virStorageBackendDiskFindLabel
to storage_backend and rename/rework the code to fit the new model.

Update the virsh.pod description to provide a more generic description
of the process since we could now use either blkid or parted to find
data on the target device.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Commit id 'df1011ca' modified virStorageBackendDiskDeleteVol to use
"dmsetup remove --force" to remove the volume, but left things in an
inconsistent state since the partition still existed on the disk and
only the device mapper device (/dev/dm-#) was removed.

Prior to commit '1895b421' (or '1ffd82bb' and '471e1c4e'), this could
go unnoticed since virStorageBackendDiskRefreshPool wasn't called.
However, the pool would be unusable since the /dev/dm-# device would
be removed even though the partition was not removed unless a multipathd
restart reset the link. That would of course make the volume appear again
in the pool after a refresh or pool start after libvirt reload.

This patch removes the 'dmsetup' logic and re-implements the partition
deletion logic for device mapper devices. The removal of the partition
via 'parted rm --script #' will cause udev device change logic to allow
multipathd to handle removing the dm-* device associated with the partition.

https://bugzilla.redhat.com/show_bug.cgi?id=1265694

Commit id '020135dc' didn't quite get the algorithm correct when a
device mapper source ended with a non numeric value (e.g. ends with
an alphabet value).

This patch modifies the 'part_separator' logic to add the "p" separator
to the attempted target path name only when specified as part_separator='yes'.

For a source name that already ends with a number, the logic doesn't change
as the part separator would need to be there.

For a source name that ends with something other than a number, this allows
the possibility that a "p" separator can be added. The default for one of
these source devices is to not add the separator.

The key for device mapper and the need for a partition separator "p" is
the presence of a number in the last character of the device name link
in /dev/mapper.  A name such as "/dev/mapper/mpatha1" would generate
a "/dev/mapper/mpatha1p1" partition, while "/dev/mapper/mpatha" would
generate partition "/dev/mapper/mpatha1". Similarly for a device
mapper entry not using friendly names or an alias, a device such as
"/dev/mapper/3600a0b80005b10ca00005ad656fd8d93" would generate a
paritition "/dev/mapper/3600a0b80005b10ca00005ad656fd8d93p1", while
a device such as "/dev/mapper/3600a0b80005b10ca00005e115729093f" would
generate a partition "/dev/mapper/3600a0b80005b10ca00005e115729093f1".
The long number is the WWID of the device. It's also possible to assign
an alias for a device mapper entry, that alias follows the same rules
with respect to ending with a number or not when adding a "p" to create
the target device path.

https://bugzilla.redhat.com/show_bug.cgi?id=1265694

In order to be able to process disk storage pool's using a multipath
device to handle the partitions, libvirt_parthelper will need a way to
not automatically add a partition separator "p" to the generated device
name for each partition found. This is designed to mimic the multipath
features known as 'user_friendly_names' and custom 'alias' name.

If the part_separator attribute is set to "no", then generation of the
multipath partition name will not include the "p" partition separator
unless the source device path name ends with a number. The generated
partition names that get passed back to libvirt are processed in order
to find the device mapper multipath (dm-#) path device.

For example, device path "/dev/mapper/mpatha" would create partitions
"/dev/mapper/mpatha1", "/dev/mapper/mpatha2", etc. instead of
"/dev/mapper/mpathap1", "/dev/mapper/mpathap2", etc. If the device
path ends with a number "/dev/mapper/mpatha1", then the algorithm
to generate names "/dev/mapper/mpatha1p1", "/dev/mapper/mpatha1p2", etc.
would be utilized.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Similar to the openflags which allow VIR_STORAGE_VOL_OPEN_NOERROR to be
passed to avoid open errors, add a 'readflags' variable so that in the
future read failures could also be ignored.

https://bugzilla.redhat.com/show_bug.cgi?id=1247987

Calculation of the extended and logical partition values for the disk
pool is complex. As the bz points out an extended partition should have
it's allocation initialized to 0 (zero) and keep the capacity as the size
dictated by the extents read.  Then for each logical partition found,
adjust the allocation of the extended partition.

Finally, previous logic tried to avoid recalculating things if a logical
partition was deleted; however, since we now have special logic to handle
the allocation of the extended partition, just make life easier by reading
the partition table again - rather than doing the reverse adjustment.

https://bugzilla.redhat.com/show_bug.cgi?id=1251461

When 'starting' up a disk pool, we need to make sure the label on the
device is valid; otherwise, the followup refreshPool will assume the
disk has been properly formatted for use. If we don't find the valid
label, then refuse the start and give a proper reason.

Let's check to ensure we can find the Partition Table in the label
and that libvirt actually recognizes that type; otherwise, when we
go to read the partitions during a refresh operation we may not be
reading what we expect.

This will expand upon the types of errors or reason that a build
would fail, so we can create more direct error messages.

Modify virStorageBackendDiskValidLabel to add a 'writelabel' parameter.
While initially for the purpose of determining whether the label should
be written during DiskBuild, a future use during DiskStart could determine
whether the pool should be started using the label found. Augment the
error messages also to give a hint as to what someone may need to do
or why the command failed.

Create a new function virStorageBackendDiskValidLabel to handle checking
whether there is a label on the device and whether it's valid or not.
While initially for the purpose of determining whether the label can be
overwritten during DiskBuild, a future use during DiskStart could determine
whether the pool should be started using the label found.

Commit id '832a9256' adjusted the code to recognize when the default
type of "unknown" was provided as the format type and to use "dos" if
found. Since the pool is built with "dos" and it could cause some
confusion when formatting the XML after building by seeing "unknown"
in the output, let's just adjust the pool's setting to "dos" so that
subsequent formats will see the value.

https://bugzilla.redhat.com/show_bug.cgi?id=1225694

Check if the disk partition to be wiped is the extended partition, if
so then disallow it. Do this via changing the wipeVol backend to check
the volume before passing to the common virStorageBackendVolWipeLocal

https://bugzilla.redhat.com/show_bug.cgi?id=1224018

The disk pool recalculates the pool allocation, capacity, and available
values each time through processing a newly created disk partition. This
created an issue with the allocation setting since the code used is shared
with the refresh path. Each path calls virStorageBackendDiskReadPartitions
which initializes the pool values and then processes the partition table
from the 'libvirt_parthelper' utility output with the only difference being
create passes a specific volume to be processed while refresh pass a NULL
indicating to process all volumes. That passed volume is check during the
virStorageBackendDiskMakeVol call to see if the current partition described
by the volume key already exists. If it exists, then no adjustments are
made to the allocation and the next entry in the output is checked.

For the create path this resulted in only the most recently created
partition size would be accounted for in the 'allocation' setting. This
patch thus checks whether the incoming volume is NULL before clearing
the pool allocation value.

Coverity points out it's possible for one of the virCommand{Output|Error}*
API's to have not allocated 'output' and/or 'error' in which case the
strstr comparison will cause a NULL deref
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Commit id '471e1c4e' only considered updating the pool if the extended
partition was removed. As it turns out removing a primary partition
would also need to update the freeExtent list otherwise the following
sequence would fail (assuming a "fresh" disk pool for /dev/sde of 500M):

$  virsh pool-info disk-pool
...
Capacity:       509.88 MiB
Allocation:     0.00 B
Available:      509.84 MiB

$ virsh vol-create-as disk-pool sde1 --capacity 300M
$ virsh vol-delete --pool disk-pool sde1
$ virsh vol-create-as disk-pool sde1 --capacity 300M
error: Failed to create vol sde1
error: internal error: no large enough free extent

$

This patch will refresh the pool, rereading the partitions, and
return

https://bugzilla.redhat.com/show_bug.cgi?id=1181062

According to the formatstorage.html description for <source> element
and "format" attribute: "All drivers are required to have a default
value for this, so it is optional."

As it turns out the disk backend did not choose a default value, so I
added a default of "msdos" if the source type is "unknown" as well as
updating the storage.html backend disk volume driver documentation to
indicate the default format is dos.

This reverts commit f1856eb6.

Now that we can update capacity from image metadata,
we don't need to skip the update.

Not all files we want to find using virFileFindResource{,Full} are
generated when libvirt is built, some of them (such as RNG schemas) are
distributed with sources. The current API was not able to find source
files if libvirt was built in VPATH.

Both RNG schemas and cpu_map.xml are distributed in source tarball.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1138516

If the provided volume name doesn't match what parted generated as the
partition name, then return a failure.

Update virsh.pod and formatstorage.html.in to describe the 'name' restriction
for disk pools as well as the usage of the <target>'s <format type='value'>.

When removing a volume that is the extended partition, all the logical
volume partitions that exist within the extended partition will also be
removed, so we need to refresh the pool to have the updated list

During virStorageBackendDiskMakeDataVol processing, if we find an extended
partition, then handle it specially when updating the capacity/allocation
rather than calling virStorageBackendUpdateVolInfo.

As it turns out, once a logical partition exists, any attempt to refresh
the pool or after libvirtd restart/reload will result in a failure to open
the extended partition device resulting in the inability to start the pool.
The downside to this is we will lose the <permissions> and <timestamps> for
the extended partition upon subsequent restart, refresh, reload since the
stat() in virStorageBackendUpdateVolTargetInfoFD will not be called. However,
since it's really only a container and shouldn't directly be used for
storage that seems reasonable.

Therefore, only use the existing code that already had a comment about
getting the allocation wrong for extended partitions for just the setting
of the extended partition data.

While checking the existing partitions in virStorageBackendDiskPartFormat,
the code would erroneously compare the volume target format type (eg, the
virStoragePartedFsType) rather than the source partition type (eg, the
virStorageVolTypeDisk) which is set during virStorageBackendDiskReadPartitions.

During virStorageBackendDiskCreateVol if virStorageBackendDiskReadPartitions
fails, then we were leaving with an error and a partition on the disk for
which there was no corresponding volume and used space on the disk which
could be reclaimable through direct parted activity. On a subsequent restart,
reload, or refresh the volume may magically appear too.

Move the API to before virStorageBackendDiskCreateVol in order to be
able to call the DeleteVol API when virStorageBackendDiskReadPartitions
fails so that we don't by chance leave a partition on the disk.

In old version of parted like parted-2.1-25, error message is shown in
stdout when printing a disk info without disk label.

    Error: /dev/sda: unrecognised disk label

This line has been moved to stderr in newer version of parted. So we
should check both stdout and stderr when locating this message.

This should fix bug:
    https://bugzilla.redhat.com/show_bug.cgi?id=1172468Signed-off-by: NHao Liu <hliu@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Coverity complains that when multiplying to 32 bit values that eventually
will be stored in a 64 bit value that it's possible the math could
overflow unless one of the values being multiplied is type cast to
the proper size.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

I'm about to add a syntax check that enforces our documented
HACKING style of always using matching {} on if-else statements.

This patch focuses on code shared between multiple drivers.

* src/conf/domain_conf.c (virDomainFSDefParseXML)
(virSysinfoParseXML, virDomainNetDefParseXML)
(virDomainWatchdogDefParseXML)
(virDomainRedirFilterUSBDevDefParseXML): Correct use of {}.
* src/conf/interface_conf.c (virInterfaceDefParseDhcp)
(virInterfaceDefParseIp, virInterfaceVlanDefFormat)
(virInterfaceDefParseStartMode, virInterfaceDefParseBondMode)
(virInterfaceDefParseBondMiiCarrier)
(virInterfaceDefParseBondArpValid): Likewise.
* src/conf/node_device_conf.c (virNodeDevCapStorageParseXML):
Likewise.
* src/conf/nwfilter_conf.c (virNWFilterRuleDetailsParse)
(virNWFilterRuleParse, virNWFilterDefParseXML): Likewise.
* src/conf/secret_conf.c (secretXMLParseNode): Likewise.
* src/cpu/cpu_x86.c (x86Baseline, x86FeatureLoad, x86ModelLoad):
Likewise.
* src/network/bridge_driver.c (networkKillDaemon)
(networkDnsmasqConfContents): Likewise.
* src/node_device/node_device_hal.c (dev_refresh): Likewise.
* src/nwfilter/nwfilter_gentech_driver.c (virNWFilterInstantiate):
Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c
(_iptablesCreateRuleInstance): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskBuildPool): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

For non-local storage drivers we can't expect to use the "scrub" tool to
wipe the volume. Split the code into a separate backend function so that
we can add protocol specific code later.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1118710

For non-local storage drivers we can't expect to use the FDStream
backend for up/downloading volumes. Split the code into a separate
backend function so that we can add protocol specific code later.

The VIR_ENUM_DECL/VIR_ENUM_IMPL helper macros already append 'Type'
to the enum name being converted; it looks silly to have functions
with 'TypeType' in their name.  Even though some of our enums have
to have a 'Type' suffix, the corresponding string conversion
functions do not.

* src/conf/secret_conf.h (VIR_ENUM_DECL): Rename virSecretUsageType.
* src/conf/storage_conf.h (VIR_ENUM_DECL): Rename
virStoragePoolAuthType, virStoragePoolSourceAdapterType,
virStoragePartedFsType.
* src/conf/domain_conf.c (virDomainDiskDefParseXML)
(virDomainFSDefParseXML, virDomainFSDefFormat): Update callers.
* src/conf/secret_conf.c (virSecretDefParseUsage)
(virSecretDefFormatUsage): Likewise.
* src/conf/storage_conf.c (virStoragePoolDefParseAuth)
(virStoragePoolDefParseSource, virStoragePoolSourceFormat):
Likewise.
* src/lxc/lxc_controller.c (virLXCControllerSetupLoopDevices):
Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskPartFormat): Likewise.
* src/util/virstorageencryption.c (virStorageEncryptionSecretParse)
(virStorageEncryptionSecretFormat): Likewise.
* tools/virsh-secret.c (cmdSecretList): Likewise.
* src/libvirt_private.syms (secret_conf.h, storage_conf.h): Export
corrected names.
Signed-off-by: NEric Blake <eblake@redhat.com>

Commit id 'ac9a0963' refactored out the 'withCapacity' for the
virStorageBackendUpdateVolInfo() API.  See:

http://www.redhat.com/archives/libvir-list/2014-April/msg00043.html

This resulted in a difference in how 'virsh vol-info --pool <poolName>
<volume>' or 'virsh vol-list vol-list --pool <poolName> --details' outputs
the capacity information for a directory pool with a qcow2 sparse file.

For example, using the following XML

mkdir /home/TestPool
cat testpool.xml
<pool type='dir'>
  <name>TestPool</name>
  <uuid>6bf80895-10b6-75a6-6059-89fdea2aefb7</uuid>
  <source>
  </source>
  <target>
    <path>/home/TestPool</path>
    <permissions>
      <mode>0755</mode>
      <owner>0</owner>
      <group>0</group>
    </permissions>
  </target>
</pool>

virsh pool-create testpool.xml
virsh vol-create-as --pool TestPool temp_vol_1 \
      --capacity 1048576 --allocation 1048576 --format qcow2
virsh vol-info --pool TestPool temp_vol_1

Results in listing a Capacity value.  Prior to the commit, the value would
be '1.0 MiB' (1048576 bytes). However, after the commit the output would be
(for example) '192.50 KiB', which for my system was the size of the volume
in my file system (eg 'ls -l TestPool/temp_vol_1' results in '197120' bytes
or 192.50 KiB). While perhaps technically correct, it's not necessarily
what the user expected (certainly virt-test didn't expect it).

This patch restores the code to not update the target capacity for this path

Instead of hardcoding LIBEXECDIR as the location of the libvirt_parthelper
binary, use virFileFindResource to optionally find it in the current
build directory.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>