Commit Graph

102 Commits

Author SHA1 Message Date
Eric Blake
44a9b872e8 snapshot: Avoid latent use-after-free when cleaning snapshots
Right now, the only callers of qemuDomainSnapshotDiscardAllMetadata()
are right before freeing the virDomainSnapshotObjList, so it did not
matter if the list's metaroot (which points to all the defined root
snapshots) is left inconsistent. But an upcoming patch will want to
clear all snapshots if a bulk redefine fails partway through, in
which case things must be reset.  Make this work by teaching the
existing virDomainSnapshotUpdateRelations() to be safe regardless of
the incoming state of the metaroot (since we don't want to leak that
internal detail into qemu code), then fixing the qemu code to use
it after deleting all snapshots. Additionally, the qemu code must
reset vm->current_snapshot if the current snapshot was removed,
regardless of whether the overall removal succeeded or failed later.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:40:18 -06:00
Eric Blake
86c0ed6f70 snapshot: Add virDomainSnapshotObjListFormat
Add a new function to output all of the domain's snapshots in one
buffer.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:31:40 -06:00
Eric Blake
cae6619ad5 snapshot: Refactor virDomainSnapshotDefFormat
Split out an internal helper that produces format into a
virBuffer, similar to what domain_conf.c does, and making
the next patch easier to write.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:31:40 -06:00
Eric Blake
c502955909 snapshot: Give virDomainSnapshotDefFormat its own flags
virDomainSnapshotDefFormat currently takes two sets of knobs:
an 'unsigned int flags' argument that can currently just be
VIR_DOMAIN_DEF_FORMAT_SECURE, and an 'int internal' argument used as
a bool to determine whether to output an additional element.  It
then reuses the 'flags' knob to call into virDomainDefFormatInternal(),
which takes a different set of flags. In fact, prior to commit 0ecd6851
(1.2.12), the 'flags' argument actually took the public
VIR_DOMAIN_XML_SECURE, which was even more confusing.  Let's borrow
from the style of that earlier commit, by introducing a function
for translating from the public flags (VIR_DOMAIN_SNAPSHOT_XML_SECURE
was just recently introduced) into a new enum specific to snapshot
formatting, and adjust all callers to use snapshot-specific enum
values when formatting, and where the formatter now uses a new
variable 'domainflags' to make it obvious when we are translating
from snapshot flags back to domain flags.  We don't even have to
use the conversion function for drivers that don't accept the
public VIR_DOMAIN_SNAPSHOT_XML_SECURE flag.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:31:40 -06:00
Eric Blake
f43eb6807e snapshot: Rework virDomainSnapshotState enum
The existing virDomainSnapshotState is a superset of virDomainState,
adding one more state (disk-snapshot) on top of valid domain states.
But as written, the enum cannot be used for gcc validation that all
enum values are covered in a strongly-typed switch condition, because
the enum does not explicitly include the values it is adding to.

Copy the style used in qemu_blockjob.h of creating new enum names
for every inherited value, and update most clients to use the new
enum names anywhere snapshot state is referenced. The exception is
two switch statements in qemu code, which instead gain a fixme
comment about odd type usage (which will be cleaned up in the next
patch). The rest of the patch is fairly mechanical (I actually did
it by temporarily s/state/xstate/ in snapshot_conf.h to let the
compiler find which spots in the code used the field, did the
obvious search and replace in those functions, then undid the rename).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:31:40 -06:00
Eric Blake
dafef600f4 snapshot: Permit redefine of offline external snapshot
Due to historical back-compat, bare 'virsh snapshot-create-as'
favors internal snapshots (but can't be used on domains with raw
storage), while 'virsh snapshot-create-as --disk-only' favors
external snapshots.  What's more, snapshots created with
--disk-only while the domain was running are marked as snapshot
state 'disk-snapshot', while snapshots created while the domain
was offline are marked as snapshot state 'shutdown' (a
'disk-snapshot' image might not be quiescent, while a 'shutdown'
snapshot always is).

But this leads to some interesting problems: if we create a
--disk-only snapshot of an offline guest, and then immediately try
to 'virsh snapshot-create --redefine' using the resulting XML to
overwrite the existing snapashot in place, things silently succeed,
but 'virsh snapshot-create --redefine --disk-only' fails with an
error message that the snapshot state is not 'disk-only'.  Worse,
if we delete the snapshot metadata first and then try to recreate
things, omitting --disk-only fails because the verification code
wants to force the default of an internal snapshot (which doesn't
work with raw disks), and using --disk-only still fails because the
snapshot XML is not 'disk-only' - making it impossible to recreate
the snapshot metadata (or to transfer it from one libvirtd host to
another).  Ideally, the presence or absence of the --disk-only
flag, and the presence or absence of an existing snapshot being
overwritten, shouldn't matter; if the XML is valid for one
situation, it should always be valid to redefine the metadata for
that snapshot.

Fix things by uniformly using virDomainSnapshotDefIsExternal()
(caching the results up front, and eliminating other 'if' clauses
now rendered redundant) when deciding whether the XML being
requested for redefinition should permit external or force internal
state capture (we got it right in only one out of three places in
the function).

See also https://bugzilla.redhat.com/1680304; this fixes the
domain-agnostic problems mentioned there, but another patch is
needed to fix further oddities with the qemu driver.  I did not
check for sure when the problems were introduced (git blame puts
some affected hunks as far back as 1.0.0), but it was definitely
been broken even before when commit 670e86bf (1.1.4) factored
redefine prep out of qemu code into the common snapshot_conf code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-26 16:28:36 -06:00
Eric Blake
d152c727c6 snapshots: Avoid term 'checkpoint' for full system snapshot
Upcoming patches plan to introduce virDomainCheckpointPtr as a new
object for use in incremental backups, along with documentation on
how incremental backups differ from snapshots.  But first, we need
to rename any existing mention of a 'system checkpoint' to instead
be a 'full system snapshot', so that we aren't overloading
the term checkpoint.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-02-26 15:48:58 -06:00
Eric Blake
c900474e6a snapshot: Saner use of uuid
Most of the code base is fairly consistent about using the name
'uuidstr' when dealing with a formatted human-readable form, and
'uuid' when dealing with the smaller raw bytes form. Fix
snapshot_conf to comply, as well as reducing the scope of a human
string to only the error message that needs it.

Signed-off-by: Eric Blake <eblake@redhat.com>
2019-02-21 11:40:04 -06:00
Peter Krempa
44601a0e96 util: Replace virStorageSourceFree with virObjectUnref
Now that virStorageSource is a subclass of virObject we can use
virObjectUnref and remove virStorageSourceFree which was a thin wrapper.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-18 10:31:21 +01:00
Peter Krempa
dcda2bf4c1 util: Introduce function for allocating virStorageSource
Add virStorageSourceNew and refactor places allocating that structure to
use the helper.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2019-02-18 10:27:30 +01:00
Cole Robinson
6a4d938dd3 Require a semicolon for VIR_ENUM_IMPL calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_IMPL calls.

Move the verify() statement to the end of the macro and drop
the semicolon, so the compiler will require callers to add a
semicolon.

While we are touching these call sites, standardize on putting
the closing parenth on its own line, as discussed here:
https://www.redhat.com/archives/libvir-list/2019-January/msg00750.html

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Peter Krempa
7129b9f354 conf: snapshot: Remove file format check from parser
We already have a way stricter check in the code which is doing the
snapshot so duplicating it in the parser does not make much sense. Also
gets rid of an ugly ternary operator.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-12-05 17:53:26 +01:00
Cole Robinson
8c496a1d00 conf: Replace SKIP_OSTYPE_CHECKS with SKIP_VALIDATE
SKIP_OSTYPE_CHECKS only hides some error reporting at this point,
so it can be foled into SKIP_VALIDATE

Acked-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2018-07-26 10:13:00 -04:00
Michal Privoznik
95cd4904e1 virDomainSnapshotDefParse: Prefer VIR_STEAL_PTR
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-06-25 07:19:53 +02:00
John Ferlan
c028c71930 conf: Add error checking to virDomainSnapshotDiskDefFormat
Commit id '43f2ccdc' called virDomainDiskSourceDefFormatInternal
rather than formatting the the disk source inline. However, it
did not handle the case where the helper failed. Over time the
helper has been renamed to virDomainDiskSourceFormat. Similar to
other consumers, if virDomainDiskSourceFormat fails, then the
formatting could be off, so it's better to fail than to continue
on with some possibly bad data. Alter the function and the caller
to check status and jump to error in that case.

Found by Coverity

Signed-off-by: John Ferlan <jferlan@redhat.com>
2018-04-19 14:23:39 -04:00
Peter Krempa
aed3d038a6 conf: Add infrastructure for disk source private data XML
VM drivers may need to store additional private data to the status XML
so that it can be restored after libvirtd restart. Since not everything
is needed add a callback infrastructure, where VM drivers can add only
stuff they need.

Note that the private data is formatted as a <privateData> sub-element
of the <disk> or <backingStore> <source> sub-element. This is done since
storing it out of band (in the VM private data) would require a complex
matching process to allow to put the data into correct place.
2017-12-14 10:24:36 +01:00
Ashish Mittal
f170548502 util: Add TLS attributes to virStorageSource
Add an optional virTristateBool haveTLS to virStorageSource to
manage whether a storage source will be using TLS.

Sample XML for a VxHS disk:

<disk type='network' device='disk'>
  <driver name='qemu' type='raw' cache='none'/>
  <source protocol='vxhs' name='eb90327c-8302-4725-9e1b-4e85ed4dc251' tls='yes'>
    <host name='192.168.0.1' port='9999'/>
  </source>
  <target dev='vda' bus='virtio'/>
</disk>

Additionally add a tlsFromConfig boolean to control whether the TLS
setting was due to domain configuration or qemu.conf global setting
in order to decide whether to Format the haveTLS setting for either
a live or saved domain configuration file.

Update the qemuxml2xmltest in order to add a test to show the proper
parsing.

Also update the docs to describe the tls attribute.

Signed-off-by: Ashish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
2017-09-28 09:45:14 -04:00
Jiri Denemark
43a90eb7e8 conf: Drop unused VIR_DOMAIN_DEF_FORMAT_UPDATE_CPU
The only real usage of this flag was removed by "cpu_conf: Drop
updateCPU from virCPUDefFormat".

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2017-09-21 15:27:25 +02:00
Pavel Hrdina
068606f85c use virXMLNodeNameEqual instead of xmlStrEqual
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2017-08-14 14:31:52 +02:00
Jiri Denemark
25af7e950a conf: Add save cookie callbacks to xmlopt
virDomainXMLOption gains driver specific callbacks for parsing and
formatting save cookies.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2017-06-07 13:36:01 +02:00
Jiri Denemark
957cd268a9 conf: Pass xmlopt to virDomainSnapshotDefFormat
This will be used later when a save cookie will become part of the
snapshot XML using new driver specific parser/formatter functions.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2017-06-07 13:36:01 +02:00
Jiri Denemark
00968dca96 conf: Make virDomainSnapshotDefFormat easier to read
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
2017-06-07 13:36:01 +02:00
Michal Privoznik
4f0aeed871 virDomainXMLOption: Introduce virDomainABIStabilityDomain
While checking for ABI stability, drivers might pose additional
checks that are not valid for general case. For instance, qemu
driver might check some memory backing attributes because of how
qemu works. But those attributes may work well in other drivers.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-06-05 09:08:52 +02:00
Peter Krempa
9e9305542e qemu: block copy: Forbid block copy to relative paths
Similarly to 29bb066915 forbid paths used with blockjobs to be relative.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1300177
2016-12-16 18:30:39 +01:00
Michal Privoznik
da6c604af2 virDomainDefParseNode: Introduce @parseOpaque argument
We want to pass the proper opaque pointer instead of NULL to
virDomainDefParseXML and subsequently virDomainDefPostParse too.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Peter Krempa
b394af162a conf: Add infrastructure for adding configuration validation
Until now we weren't able to add checks that would reject configuration
once accepted by the parser. This patch adds a new callback and
infrastructure to add such checks. In this patch all the places where
rejecting a now-invalid configuration wouldn't be a good idea are marked
with a new parser flag.
2016-06-07 13:02:20 +02:00
Erik Skultety
cc48d3a122 util: Add a return value to void hash iterators
Our existing virHashForEach method iterates through all items disregarding the
fact, that some of the iterators might have actually failed. Errors are usually
dispatched through an error element in opaque data which then causes the
original caller of virHashForEach to return -1. In that case, virHashForEach
could return as soon as one of the iterators fail. This patch changes the
iterator return type and adjusts all of its instances accordingly, so the
actual refactor of virHashForEach method can be dealt with later.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
2016-02-17 12:46:34 +01:00
Peter Krempa
b60af444cc conf: snapshot: Avoid autogenerating duplicate snapshot names
The snapshot name generator truncates the original file name after a '.'
and replaces the suffix with the snapshot name. If two disks source
images differ only in the suffix portion, the generated name will be
duplicate.

Since this is a corner case just error out stating that a duplicate name
was generated. The user can work around this situation by providing
the file names explicitly.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1283085
2016-02-11 15:33:10 +01:00
Peter Krempa
4319444d05 conf: snapshot: Refactor virDomainSnapshotDefAssignExternalNames
Get rid of one indentation level by negating condition and remove ugly
pointer arithmetic at the cost of one extra allocation.
2016-02-11 15:33:10 +01:00
Peter Krempa
040a4fe7f6 conf: snapshot: Extract code to generate default external file names 2016-02-11 15:33:01 +01:00
Peter Krempa
d5c7655ca5 conf: snapshot: Rename disksorter to virDomainSnapshotCompareDiskIndex
Stick to the naming pattern.
2016-02-11 15:32:48 +01:00
Joao Martins
b8b03f64e1 conf: add caps to virDomainSnapshotDefFormat
The virDomainSnapshotDefFormat calls into virDomainDefFormat,
so should be providing a non-NULL virCapsPtr instance. On the
qemu driver we change qemuDomainSnapshotWriteMetadata to also
include caps since it calls virDomainSnapshotDefFormat.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
2016-02-05 10:57:39 +00:00
Joao Martins
d239a5427f conf: add caps to virDomainDefFormat*
And use the newly added caps->host.netprefix (if it exists) for
interface names that match the autogenerated target names.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
2016-02-04 12:38:26 +00:00
Cole Robinson
835cf84b7e domain: conf: Drop expectedVirtTypes
This needs to specified in way too many places for a simple validation
check. The ostype/arch/virttype validation checks later in
DomainDefParseXML should catch most of the cases that this was covering.
2015-04-20 16:43:43 -04:00
Cole Robinson
f1a89a8b6d domain: conf: Don't validate VM ostype/arch at daemon startup
When parsing XML, we validate the passed ostype + arch combo against
the detected hypervisor capabilities. This has led to the following
problem:

- Define x86 qemu guest
- qemu is inadvertently removed from the host
- libvirtd is restarted. fails to parse VM config since arch is removed
- 'virsh list --all' is now empty, user is wondering where their VMs went

Add a new internal flag VIR_DOMAIN_DEF_PARSE_SKIP_OSTYPE_CHECKS. Use
it when loading VM and snapshot configs from disk.

https://bugzilla.redhat.com/show_bug.cgi?id=1043572
2015-04-20 16:36:35 -04:00
John Ferlan
29359e99bf snapshot: Change 'index' to 'idx'
Forthcoming syntax check rule will disallow usage of 'int index', so
change it for snapshot
2015-04-14 11:18:28 -04:00
Ján Tomko
c59304e7e8 Use XPath when parsing snapshot disk definition
Instead of going through XML nodes in a loop and
having to check if they are duplicate.
2015-04-13 15:07:45 +02:00
Ján Tomko
22fd3ac38f Introduce virBitmapIsBitSet
A helper that never returns an error and treats bits out of bitmap range
as false.

Use it everywhere we use ignore_value on virBitmapGetBit, or loop over
the bitmap size.
2015-03-13 15:31:33 +01:00
Daniel P. Berrange
0ecd685109 Give virDomainDef parser & formatter their own flags
The virDomainDefParse* and virDomainDefFormat* methods both
accept the VIR_DOMAIN_XML_* flags defined in the public API,
along with a set of other VIR_DOMAIN_XML_INTERNAL_* flags
defined in domain_conf.c.

This is seriously confusing & error prone for a number of
reasons:

 - VIR_DOMAIN_XML_SECURE, VIR_DOMAIN_XML_MIGRATABLE and
   VIR_DOMAIN_XML_UPDATE_CPU are only relevant for the
   formatting operation
 - Some of the VIR_DOMAIN_XML_INTERNAL_* flags only apply
   to parse or to format, but not both.

This patch cleanly separates out the flags. There are two
distint VIR_DOMAIN_DEF_PARSE_* and VIR_DOMAIN_DEF_FORMAT_*
flags that are used by the corresponding methods. The
VIR_DOMAIN_XML_* flags received via public API calls must
be converted to the VIR_DOMAIN_DEF_FORMAT_* flags where
needed.

The various calls to virDomainDefParse which hardcoded the
use of the VIR_DOMAIN_XML_INACTIVE flag change to use the
VIR_DOMAIN_DEF_PARSE_INACTIVE flag.
2015-01-13 16:26:12 +00:00
Daniel P. Berrange
4d6ed1bf0b Don't use VIR_DOMAIN_XML_SECURE when parsing XML
The VIR_DOMAIN_XML_SECURE flag only has effect on the formatting
of XML so should not be passed to virDomainDefParseNode
2015-01-13 10:43:07 +00:00
Peter Krempa
0255660658 storage: rbd: qemu: Add support for specifying internal RBD snapshots
Some storage systems have internal support for snapshots. Libvirt should
be able to select a correct snapshot when starting a VM.

This patch adds a XML element to select a storage source snapshot for
the RBD protocol which supports this feature.
2014-11-21 14:37:02 +01:00
Eric Blake
eb9093763f maint: forbid 'int foo = true'
I noticed this while working on qemuDomainGetBlockInfo.  Assigning
a bool value to an int variable compiles fine, but raises red flags
on the maintenance front as it becomes too easy to assign -1 or 2
or any other non-bool value to the same variable.

* cfg.mk (sc_prohibit_int_assign_bool): New rule.
* src/conf/snapshot_conf.c (virDomainSnapshotRedefinePrep): Fix
offenders.
* src/qemu/qemu_driver.c (qemuDomainGetBlockInfo)
(qemuDomainSnapshotCreateXML): Likewise.
* src/test/test_driver.c (testDomainSnapshotAlignDisks):
Likewise.
* src/util/vircgroup.c (virCgroupSupportsCpuBW): Likewise.
* src/util/virpci.c (virPCIDeviceBindToStub): Likewise.
* src/util/virutil.c (virIsCapableVport): Likewise.
* tools/virsh-domain-monitor.c (cmdDomMemStat): Likewise.
* tools/virsh-domain.c (cmdBlockResize, cmdScreenshot)
(cmdInjectNMI, cmdSendKey, cmdSendProcessSignal)
(cmdDetachInterface): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-11-19 08:20:39 -07:00
Peter Krempa
2f2a992205 conf: snapshot: Don't default-snapshot empty drives
If a (floppy) drive isn't selected for snapshot explicitly and is empty
don't try to snapshot it. For external snapshots this would fail as we
can't generate a name for the snapshot from an empty drive.

Reported-by: Pavel Hrdina <phrdina@redhat.com>
2014-09-12 09:37:37 +02:00
Peter Krempa
29bb066915 snapshot: conf: Enforce absolute paths on disk and memory images
RNG schema as well as the qemu driver requires absolute paths for memory
and disk snapshot image files but the XML parser was not enforcing it.
Add checks to avoid problems in qemu where the configuration it creates
is invalid.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1126329
2014-08-06 17:58:26 +02:00
Ján Tomko
92a8e72f9d Use virBufferCheckError everywhere we report OOM error
Replace:
if (virBufferError(&buf)) {
    virBufferFreeAndReset(&buf);
    virReportOOMError();
    ...
}

with:
if (virBufferCheckError(&buf) < 0)
    ...

This should not be a functional change (unless some callers
misused the virBuffer APIs - a different error would be reported
then)
2014-07-03 10:48:14 +02:00
Eric Blake
00c6327a12 conf: store snapshot source as pointer, for easier manipulation
As part of the work on backing chains, I'm finding that it would
be easier to directly manipulate chains of pointers (adding a
snapshot merely adjusts pointers to form the correct list) rather
than copy data from one struct to another. This patch converts
snapshot source to be a pointer.

In this patch, the pointer is ALWAYS allocated (any code that
increases ndisks now also allocates a source pointer for each
new disk), and all other changes are just mechanical fallout of
the new type; there should be no functional change.  It is
possible that we may want to leave the pointer NULL for internal
snapshots in a later patch, but as that requires a closer audit
of the source to ensure we don't fault on a null dereference, I
didn't do it here.

* src/conf/snapshot_conf.h (_virDomainSnapshotDiskDef): Change
type of src.
* src/conf/snapshot_conf.c: Adjust all clients.
* src/qemu/qemu_conf.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-06-06 09:56:27 -06:00
Eric Blake
db7d7c0ee8 conf: restrict external snapshots to backing store formats
Domain snapshots should only permit an external snapshot into
a storage format that permits a backing chain, since the new
snapshot file necessarily must be backed by the existing file.
The C code for the qemu driver is a little bit stricter in
currently enforcing only qcow2 or qed, but at the XML parser
level, including virt-xml-validate, it is fairly easy to
enforce that a user can't request a 'raw' external snapshot.

* docs/schemas/storagecommon.rng (storageFormat): Split out...
(storageFormatBacking): ...new sublist.
* docs/schemas/domainsnapshot.rng (disksnapshotdriver): Use new
type.
* src/util/virstoragefile.h (virStorageFileFormat): Rearrange for
easier code management.
* src/util/virstoragefile.c (virStorageFileFormat, fileTypeInfo):
Likewise.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML): Use
new marker to limit selection of formats.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-04-15 13:57:15 +02:00
Peter Krempa
93c1f2cd70 conf: Refactor helpers to retrieve actual storage type
Now that the storage source definition is uniform convert the helpers to
retrieve the actual storage type to a single one.
2014-04-09 14:20:40 +02:00
Eric Blake
9673418ce5 conf: track when storage type is still undetermined
Right now, virStorageFileMetadata tracks bool backingStoreIsFile
for whether the backing string specified in metadata can be
resolved as a file (covering both block and regular file
resources) or is treated as a network protocol.  But when
merging this struct with virStorageSource, it will be easier
to just actually track which type of resource it is, as well
as have a reserved value for the case where the resource type
is unknown (or had an error during probing).

* src/util/virstoragefile.h (virStorageType): Add a placeholder
value, swap order to match similar public enum.
* src/util/virstoragefile.c (virStorage): Update string mapping.
* src/conf/domain_conf.c (virDomainDiskSourceParse)
(virDomainDiskDefParseXML, virDomainDiskDefFormat)
(virDomainDiskSourceFormat): Adjust clients.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML):
Likewise.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotPrepareDiskExternalBackingInactive)
(qemuDomainSnapshotPrepareDiskExternalOverlayActive)
(qemuDomainSnapshotPrepareDiskExternalOverlayInactive)
(qemuDomainSnapshotPrepareDiskInternal)
(qemuDomainSnapshotCreateSingleDiskActive): Likewise.
* src/qemu/qemu_command.c (qemuGetDriveSourceString): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-04-04 10:58:23 -06:00