A device may be formatted using some sort of disk partition format type.
We can check that using the blkid_ API's as well - so alter the logic to
allow checking the device for both a filesystem and a disk partition.
Signed-off-by: John Ferlan <jferlan@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1363586
Commit id '27758859' introduced the "NO_OVERWRITE" flag check for
file system backends; however, the implementation, documentation,
and algorithm was inconsistent. For the "flag" description for the
API the flag was described as "Do not overwrite existing pool";
however, within the storage backend code the flag is described
as "it probes to determine if filesystem already exists on the
target device, renurning an error if exists".
The code itself was implemented using the paradigm to set up the
superblock probe by creating a filter that would cause the code
to only search for the provided format type. If that type wasn't
found, then the algorithm would return success allowing the caller
to format the device. If the format type already existed on the
device, then the code would fail indicating that the a filesystem
of the same type existed on the device.
The result is that if someone had a file system of one type on the
device, it was possible to overwrite it if a different format type
was specified in updated XML effectively trashing whatever was on
the device already.
This patch alters what NO_OVERWRITE does for a file system backend
to be more realistic and consistent with what should be expected when
the caller requests to not overwrite the data on the disk.
Rather than filter results based on the expected format type, the
code will allow success/failure be determined solely on whether the
blkid_do_probe calls finds some known format on the device. This
adjustment also allows removal of the virStoragePoolProbeResult
enum that was under utilized.
If it does find a formatted file system different errors will be
generated indicating a file system of a specific type already exists
or a file system of some other type already exists.
In the original virsh support commit id 'ddcd5674', the description
for '--no-overwrite' within the 'pool-build' command help output
has an ambiguous "of this type" included in the short description.
Compared to the longer description within the "Build a given pool."
section of the virsh.pod file it's more apparent that the meaning
of this flag would cause failure if a probe of the target already
has a filesystem.
So this patch also modifies the short description to just be the
antecedent of the 'overwrite' flag, which matches the API description.
This patch also modifies the grammar in virsh.pod for no-overwrite
as well as reworking the paragraph formats to make it easier to read.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Rename virStorageBackendFileSystemProbe and to virStorageBackendBLKIDFindFS
and move to the more common storage_backend module.
Create a shim virStorageBackendDeviceIsEmpty which will make the call
to the virStorageBackendBLKIDFindFS and check the return value.
Signed-off-by: John Ferlan <jferlan@redhat.com>
The public virSecret object has a single "usage_id" field
but the virSecretDef object has a different 'char *' field
for each usage type, but the code all assumes every usage
type has a corresponding single string. Get rid of the
pointless union in virSecretDef and just use "usage_id"
everywhere. This doesn't impact public XML format, only
the internal handling.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of having duplicated code in qemuStorageLimitsRefresh and
virStorageBackendUpdateVolTargetInfo to get capacity specific data
about the storage backing source or volume -- create a common API
to handle the details for both.
As a side effect, virStorageFileProbeFormatFromBuf returns to being
a local/static helper to virstoragefile.c
For the QEMU code - if the probe is done, then the format is saved so
as to avoid future such probes.
For the storage backend code, there is no need to deal with the probe
since we cannot call the new API if target->format == NONE.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Instead of having duplicated code in qemuStorageLimitsRefresh and
virStorageBackendUpdateVolTargetInfoFD to fill in the storage backing
source or volume allocation, capacity, and physical values - create a
common API that will handle the details for both.
The common API will fill in "default" capacity values as well - although
those more than likely will be overridden by subsequent code. Having just
one place to make the determination of what the values should be will
make things be more consistent.
For the QEMU code - the data filled in will be for inactive domains
for the GetBlockInfo and DomainGetStatsOneBlock API's. For the storage
backend code - the data will be filled in during the volume updates.
Signed-off-by: John Ferlan <jferlan@redhat.com>
There was a missing check for vol->target.encryption being NULL
at one particular place (modified by commit a48c71411) which caused a crash
when user attempted to create a raw volume using a non-raw file volume as
source.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1363636
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Let's cleanly differentiate what wiping a volume does for ploop and
other volumes so it's more readable what is done for each one instead of
branching out multiple times in different parts of the same function.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Some functions use volume specification merely to use the target path
from it. Let's change it to pass the path only so that it can be used
for other files than just volumes.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
This is done in order to call them in next patches from each other and
definitions would be missing otherwise.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
The current LUKS support has a "luks" volume type which has
a "luks" encryption format.
This partially makes sense if you consider the QEMU shorthand
syntax only requires you to specify a format=luks, and it'll
automagically uses "raw" as the next level driver. QEMU will
however let you override the "raw" with any other driver it
supports (vmdk, qcow, rbd, iscsi, etc, etc)
IOW the intention though is that the "luks" encryption format
is applied to all disk formats (whether raw, qcow2, rbd, gluster
or whatever). As such it doesn't make much sense for libvirt
to say the volume type is "luks" - we should be saying that it
is a "raw" file, but with "luks" encryption applied.
IOW, when creating a storage volume we should use this XML
<volume>
<name>demo.raw</name>
<capacity>5368709120</capacity>
<target>
<format type='raw'/>
<encryption format='luks'>
<secret type='passphrase' uuid='0a81f5b2-8403-7b23-c8d6-21ccd2f80d6f'/>
</encryption>
</target>
</volume>
and when configuring a guest disk we should use
<disk type='file' device='disk'>
<driver name='qemu' type='raw'/>
<source file='/home/berrange/VirtualMachines/demo.raw'/>
<target dev='sda' bus='scsi'/>
<encryption format='luks'>
<secret type='passphrase' uuid='0a81f5b2-8403-7b23-c8d6-21ccd2f80d6f'/>
</encryption>
</disk>
This commit thus removes the "luks" storage volume type added
in
commit 318ebb36f1
Author: John Ferlan <jferlan@redhat.com>
Date: Tue Jun 21 12:59:54 2016 -0400
util: Add 'luks' to the FileTypeInfo
The storage file probing code is modified so that it can probe
the actual encryption formats explicitly, rather than merely
probing existance of encryption and letting the storage driver
guess the format.
The rest of the code is then adapted to deal with
VIR_STORAGE_FILE_RAW w/ VIR_STORAGE_ENCRYPTION_FORMAT_LUKS
instead of just VIR_STORAGE_FILE_LUKS.
The commit mentioned above was included in libvirt v2.0.0.
So when querying volume XML this will be a change in behaviour
vs the 2.0.0 release - it'll report 'raw' instead of 'luks'
for the volume format, but still report 'luks' for encryption
format. I think this change is OK because the storage driver
did not include any support for creating volumes, nor starting
guets with luks volumes in v2.0.0 - that only since then.
Clearly if we change this we must do it before v2.1.0 though.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Commit id '5e46d7d6' did not take into account that usage of a luks
volume will require usage of the master key encrypted passphrase for
a QEMU environment. So rather than allow creation of something that
won't be usable, just fail the creation.
Partially resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=1301021
If the volume xml was looking to create a luks volume take the necessary
steps in order to make that happen.
The processing will be:
1. create a temporary file (virStorageBackendCreateQemuImgSecretPath)
1a. use the storage driver state dir path that uses the pool and
volume name as a base.
2. create a secret object (virStorageBackendCreateQemuImgSecretObject)
2a. use an alias combinding the volume name and "_luks0"
2b. add the file to the object
3. create/add luks options to the commandline (virQEMUBuildLuksOpts)
3a. at the very least a "key-secret=%s" using the secret object alias
3b. if found in the XML the various "cipher" and "ivgen" options
Signed-off-by: John Ferlan <jferlan@redhat.com>
The modification of .volWipe callback wipes ploop volume using one of
given wiping algorithm: dod, nnsa, etc.
However, in case of ploop volume we need to reinitialize root.hds and DiskDescriptor.xml.
v2:
- added check on ploop tools presens
- virCommandAddArgFormat changed to virCommandAddArg
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
In order to use more common code and set up for a future type, modify the
encryption secret to allow the "usage" attribute or the "uuid" attribute
to define the secret. The "usage" in the case of a volume secret would be
the path to the volume as dictated by the backwards compatibility brought
on by virStorageGenerateQcowEncryption where it set up the usage field as
the vol->target.path and didn't allow someone to provide it. This carries
into virSecretObjListFindByUsageLocked which takes the secret usage attribute
value from from the domain disk definition and compares it against the
usage type from the secret definition. Since none of the code dealing
with qcow/qcow2 encryption secrets uses usage for lookup, it's a mostly
cosmetic change. The real usage comes in a future path where the encryption
is expanded to be a luks volume and the secret will allow definition of
the usage field.
This code will make use of the virSecretLookup{Parse|Format}Secret common code.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Create a helper virStorageBackendCreateQemuImgSetOptions to set either
the qemu-img -o options or the previous mechanism using -F
Signed-off-by: John Ferlan <jferlan@redhat.com>
Since we support QEMU 0.12 and later, checking for support of specific flags
added prior to that isn't necessary.
Thus start with the base of having the "-o options" available for the
qemu-img create option and then determine whether we have the compat
option for qcow2 files (which would be necessary up through qemu 2.0
where the default changes to compat 0.11).
Adjust test to no long check for NONE and FLAG options as well was removing
results of tests that would use that option.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Split out a helper from virStorageBackendCreateQemuImgCmdFromVol
to check the encryption - soon a new encryption sheriff will be
patroling and that'll mean all sorts of new checks.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Remove all the plumbing needed for the different qcow-create/kvm-img
non-raw file creation.
We can drop the error messages because CreateQemuImg will thrown an
error for us but with slightly less fidelity (unable to find qemu-img),
which I think is acceptable given the unlikeliness of that error in
practice.
This an ubuntu/debian packaging convention. At one point it may have
been an actually different binary, but at least as of ubuntu precise
(the oldest supported ubuntu distro, released april 2012) kvm-img is
just a symlink to qemu-img for back compat.
I think it's safe to drop support for it
qcow-create was a crippled qemu-img impl that shipped with xen. I
think supporting this was only relevant for really old distros
that didn't have a proper qemu package, like early RHEL5. I think
it's fair to drop support
In case of ploop volume, target path of the volume is the path to the
directory that contains image file named root.hds and DiskDescriptor.xml.
While using uploadVol and downloadVol callbacks we need to open root.hds
itself.
Upload or download operations with ploop volume are only allowed when
images do not have snapshots. Otherwise operation fails.
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Refreshes meta-information such as allocation, capacity, format, etc.
Ploop volumes differ from other volume types. Path to volume is the path
to directory with image file root.hds and DiskDescriptor.xml.
https://openvz.org/Ploop/format
Due to this fact, operations of opening the volume have to be done once
again. get the information.
To decide whether the given volume is ploops one, it is necessary to check
the presence of root.hds and DiskDescriptor.xml files in volumes' directory.
Only in this case the volume can be manipulated as the ploops one.
Such strategy helps us to resolve problems that might occure, when we
upload some other volume type from ploop source.
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
These callbacks let us to create ploop volumes in dir, fs and etc. pools.
If a ploop volume was created via buildVol callback, then this volume
is an empty ploop device with DiskDescriptor.xml.
If the volume was created via .buildFrom - then its content is similar to
input volume content.
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Do not store the return value of called functions in the same variable
as the (future) return value of the current function.
This makes tracking the origin of the value easier and reduces
the chance of introducing a new point of exit without resetting
the return value back to -1.
This new algorithm adds support for wiping volumes using TRIM.
It does not overwrite all the data in a volume, but it tells the
backing storage pool/driver that all bytes in a volume can be
discarded.
It depends on the backing storage pool how this is handled.
A SCSI backend might send UNMAP commands to remove all data present
on a LUN.
A Ceph backend might use rbd_discard() to instruct the Ceph cluster
that all data on that RBD volume can be discarded.
Signed-off-by: Wido den Hollander <wido@widodh.nl>
Use the cast of (virStorageVolWipeAlgorithm) adding the missing case:'s
(VIR_STORAGE_VOL_WIPE_ALG_ZERO and VIR_STORAGE_VOL_WIPE_ALG_LAST).
Additionally, the old code would also still run the SCRUB command on
default since it didn't go to cleanup when a invalid flag was supplied.
We now go to cleanup and exit if a invalid flag would be provided.
Signed-off-by: Wido den Hollander <wido@widodh.nl>
The only caller always passes 0 for the extent start.
Drop the 'extent_start' parameter, as well as the mention of extents
from the function name.
Change off_t extent_length to unsigned long long wipe_len, as well as the
'remain' variable.
Return -1:
* on all failures of fdatasync. Instead of propagating -errno
all the way up to the virStorageVolWipe API, which is documented
to return 0 or -1.
* after a partial wipe. If safewrite failed, we would re-use the
non-negative return value of lseek (which should be 0 in this case,
because that's the only offset we seek to).
I found this useful while processing a volume that wouldn't end up
showing up in the resulting list of block volumes. In this case, the
partition type wasn't found in the disk_types table.
Similar to the openflags VIR_STORAGE_VOL_OPEN_NOERROR processing, if some
read processing operation fails, check the readflags for the corresponding
error flag being set. If so, rather then causing an error - use VIR_WARN
to flag the error, but return -2 which some callers can use to perform
specific actions. Use a new VIR_STORAGE_VOL_READ_NOERROR flag in a new
VolReadErrorMode enum.
While processing the volume for lseek, virFileReadHeaderFD, and
virStorageFileGetMetadataFromBuf - failure would cause an error,
but ret would not be set. That would result in an error message being
sent, but successful status being returned.
Just so it's clearer what to expect upon input and what types of return
values could be generated. These were loosely copied from existing
virStorageBackendUpdateVolTargetInfoFD.
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=1282288
Rather than using just open on the path, allow for the possibility that
the path to be opened resides on an NFS root-squash target and was created
under a different uid/gid.
Without using virFileOpenAs an attempt to get the volume size data may fail
if the current user doesn't have permissions to read the volume, such as
would be the case if mode wasn't supplied in the volume XML and the default
VIR_STORAGE_DEFAULT_VOL_PERM_MODE (e.g. 0600) was used. Under this scenario
the owner/group is not root:root, thus this path run under root would fail
to open/read the volume.
NB: The virFileOpenAs code using OPEN_FORK will only work when the failure
is not EACESS/EPERM and the path resolves to a shared file system.
https://bugzilla.redhat.com/show_bug.cgi?id=1282288
Although commit id '77346f27' resolves part of the problem regarding creating
a qemu-img image in an NFS root-squash environment, it really didn't fix the
entire problem. Unfortunately it only masked the problem. It seems qemu-img
must open/create the image using 0644, which if used by target.perms would
result in the chmod not being called since the mode desired and set match.
Although qemu-img could conceivably ignore the mode when creating, libvirt
has more knowledge of the environment and can make the adjustment to the
mode far more easily by using virFileOpenAs with VIR_FILE_OPEN_FORCE_MODE.
If that's successful, then we know on return the file will have the right
owner and mode, so we can declare success
After successfully returning from virFileOpenAs, if subsequent calls fail,
then we need to remove the file since our caller expects that failures after
creation will remove the created file.
After a successful qemu-img/qcow-create of the backing file, if we
fail to stat the file, change it owner/group, or mode, then the
cleanup path should remove the file.
