Commit Graph

129 Commits

Author SHA1 Message Date
Eric Blake
57387ff54b snapshot: Make virDomainSnapshotDef a virObject
This brings about a couple of benefits:
- use of VIR_AUTOUNREF() simplifies several callers
- Fixes a todo about virDomainMomentObjList not being polymorphic enough

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
2019-05-09 10:02:53 -05:00
Eric Blake
7fe07761a7 snapshot: Add virDomainSnapshotDefNew
In preparation for making virDomainSnapshotDef a descendant of
virObject, it is time to fix all callers that allocate an object to
use virDomainSnapshotDefNew() instead of VIR_ALLOC().  Fortunately,
there aren't very many :)

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
2019-05-09 09:51:51 -05:00
Eric Blake
098043eddd snapshot: s/current/parent/ as prep for virObject
VIR_CLASS_NEW insists that descendents of virObject have 'parent' as
the name of their inherited base class member at offset 0. While it
would be possible to write a new class-creation macro that takes the
actual field name 'current', and rewrite VIR_CLASS_NEW to call the new
macro with the hard-coded name 'parent', it seems less confusing if
all object code uses similar naming. Thus, this is a mechanical rename
in preparation of making virDomainSnapshotDef a descendent of
virObject.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
2019-05-09 09:48:07 -05:00
Eric Blake
36603bc568 snapshot: s/parent/parent_name/ as prep for virObject
VIR_CLASS_NEW insists that descendents of virObject have 'parent' as
the name of their inherited base class member at offset 0. While it
would be possible to write a new class-creation macro that takes the
actual field name, and rewrite VIR_CLASS_NEW to call the new macro
with the hard-coded name 'parent', so that we could make
virDomainMomentDef use a custom name for its base class, it seems less
confusing if all object code uses similar naming. Thus, this is a
mechanical rename in preparation of making virDomainSnapshotDef a
descendent of virObject, when we can no longer use 'parent' for a
different purpose than the base class.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
2019-05-09 09:43:41 -05:00
Eric Blake
1ec3e39742 conf: Add parameter to virDomainDiskSourceFormat
Commits 4bc42986 and 218c81ea removed virDomainStorageSourceFormat on
the grounds that there were no external callers; however, the upcoming
backup code wants to output a <target> (push mode) or <scratch> (pull
mode) element that is in all other respects identical to a domain's
<source> element, where the previous virDomainStorageSourceFormat fit
the bill nicely. But rather than reverting the commits, it's easier to
just add an additional parameter for the element name to use, and
update all callers.

Signed-off-by: Eric Blake <eblake@redhat.com>
2019-05-06 18:05:17 -05:00
Eric Blake
df2ae0d042 snapshot: Allow for post-parse override
Wire up the accessor functions necessary for the testsuite to install
an alternative post-parse handler from normal drivers. I could have
modified the signature for virDomainXMLOptionNew() to take another
parameter, but thought it was easier to add a new set function rather
than chase down all existing callers. Until code actually sets the
override, there is no change in behavior.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
2019-04-16 21:55:59 -05:00
Eric Blake
5ba4d81ce9 snapshot: Factor out post-parse code
Move the non-deterministic code that sets snapshot properties
independently of what the incoming XML described to instead live in a
default post-parse function common to virDomainMoment (as checkpoints
will also reuse it in later patches). This patch is just code motion,
with no difference to any callers; but the next patch will further
refactor things to allow for a per-driver override, used by the
testsuite to perform deterministic post-parse actions for better
coverage of parser/formatter code.

Note that the post-parse code is intentionally not run during a
snapshot redefine, since that code path already requires a valid
snapshot name and creation time from the XML.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
2019-04-16 21:55:59 -05:00
Eric Blake
a007fcab3b snapshot: Don't expose testsuite-only state in snapshot XML
None of the existing drivers actually use the 0-valued 'nostate'
snapshot state; rather, it was a fluke of implementation. In fact,
some drivers, like qemu, actively reject 'nostate' as invalid during a
snapshot redefine. Normally, a driver computes the state post-parse
from the current domain, and thus virDomainSnapshotGetXMLDesc() will
never expose the state. However, since the testsuite lacks any
associated domain to copy state from, and lacks post-parse processing
that normal drivers have, the testsuite output had several spots with
the state, coupled with a regex filter to ignore the oddity.

It is better to follow the lead of other XML defaults, by not
outputting anything during format if post-parse defaults have not been
applied, and rejecting the default value during parsing. The testsuite
needs a bit of an update, by adding another flag for when to simulate
a post-parse action of setting a snapshot state, but none of the
drivers are impacted other than rejecting XML that was previously
already suspicious in nature.

Similarly, don't expose creation time 0 (for now, only possible if a
user redefined a snapshot to claim creation at the Epoch, but also
happens once setting the creation time is deferred to a post-parse
handler).

This is also a step towards cleaning up snapshot_conf.c to separate
its existing post-parse work (namely, setting the creationTime and
default snapshot name) from the pure parsing work, so that we can get
rid of the testsuite hack of regex filtering of the XML and instead
have more accurate testing of our parser/formatter code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
2019-04-16 21:55:52 -05:00
Cole Robinson
1d31526b52 Always put _LAST enums on second line of VIR_ENUM_IMPL
Standardize on putting the _LAST enum value on the second line
of VIR_ENUM_IMPL invocations. Later patches that add string labels
to VIR_ENUM_IMPL will push most of these to the second line anyways,
so this saves some noise.

Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-04-11 12:47:23 -04:00
Peter Krempa
dfaf170df5 conf: Replace virDomainDiskSourceParse by virDomainStorageSourceParse
virDomainDiskSourceParse was now just a thin wrapper without any extra
value. Replace all usage of it by the function it calls and remove the
function.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-03 11:58:09 +02:00
Peter Krempa
5f6f803ca1 conf: Merge virDomainDiskSourceFormatInternal into virDomainDiskSourceFormat
Remove the wrapper and fix callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-03 11:58:09 +02:00
Eric Blake
a6d822cee3 Revert "snapshot: Allow NULL to virDomainSnapshotObjGetDef"
This reverts commit 6b90a84738.

It turns out gcc -O2 is not happy with it, complaining:

/home/pipo/libvirt/src/qemu/qemu_driver.c: In function 'qemuDomainSnapshotCreateXML':
/home/pipo/libvirt/src/qemu/qemu_driver.c:15389:26: error: potential null pointer dereference [-Werror=null-dereference]
     bool memory = snapdef->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
                   ~~~~~~~^~~~~~~~
/home/pipo/libvirt/src/qemu/qemu_driver.c:15389:26: error: potential null pointer dereference [-Werror=null-dereference]
In file included from /home/pipo/libvirt/src/util/virbuffer.h:27,
                 from /home/pipo/libvirt/src/conf/capabilities.h:27,
                 from /home/pipo/libvirt/src/conf/domain_conf.h:32,
                 from /home/pipo/libvirt/src/qemu/qemu_agent.h:26,
                 from /home/pipo/libvirt/src/qemu/qemu_driver.c:40:
/home/pipo/libvirt/src/util/viralloc.h:125:34: error: potential null pointer dereference [-Werror=null-dereference]
 # define VIR_ALLOC_N(ptr, count) virAllocN(&(ptr), sizeof(*(ptr)), (count), true, \
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                            VIR_FROM_THIS, __FILE__, __FUNCTION__, __LINE__)
                                            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/pipo/libvirt/src/qemu/qemu_driver.c:15103:9: note: in expansion of macro 'VIR_ALLOC_N'
     if (VIR_ALLOC_N(ret, snapdef->ndisks) < 0)
         ^~~~~~~~~~~
/home/pipo/libvirt/src/qemu/qemu_driver.c:15798:45: error: null pointer dereference [-Werror=null-dereference]
             virDomainSnapshotObjGetDef(snap)->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL) {
             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~

As the patch simplified one or two callers at the risk of making
many other callers now candidates to trigger aggressive compiler
warnings, it isn't worth it.

Signed-off-by: Eric Blake <eblake@redhat.com>
2019-03-27 09:21:45 -05:00
Eric Blake
6b90a84738 snapshot: Allow NULL to virDomainSnapshotObjGetDef
Doing so can simplify some callers.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-27 08:14:42 -05:00
Eric Blake
0b4fac6afd Revert "snapshot: Add virDomainSnapshotObjListFormat"
This reverts commit 86c0ed6f70, and
subsequent refactorings of the function into new files.  There are no
callers of this function - I had originally proposed it for
implementing a new bulk snapshot API, but that proved to be too
invasive given RPC limits. I also tried using it for streamlining how
the qemu driver stores snapshot state across libvirtd restarts
internally, but in the end, the risks of a new internal format
outweighed the benefits of one file per snapshot.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-26 15:07:47 -05:00
Eric Blake
9884b2d185 snapshot: Avoid infloop during REDEFINE
Commit 55c2ab3e accidentally introduced an infinite loop while
checking whether a redefined snapshot would cause an infinite loop in
chasing its parents back to a root.  Alas, 'make check' did not catch
it, so my next patch will be a testsuite improvement that would have
hung and prevented the bug from being checked in to begin with.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2019-03-25 08:50:45 -05:00
Eric Blake
e055a816af snapshot: Rename virDomainSnapshotObjPtr
Now that the core of SnapshotObj is agnostic to snapshots and can be
shared with upcoming checkpoint code, it is time to rename the struct
and the functions specific to list operations. A later patch will
shuffle which file holds the common code. This is a fairly mechanical
patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:34 -05:00
Eric Blake
1ab05da228 snapshot: Switch type of virDomainSnapshotObj.def
Another step towards making the object list reusable for both
snapshots and checkpoints: the list code only ever needs items that
are in the common virDomainMomentDef base type. This undoes a lot of
the churn in accessing common members added in the previous patch, and
the bulk of the patch is mechanical. But there was one spot where I
had to unroll a VIR_STEAL_PTR to work around changed types.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:34 -05:00
Eric Blake
ffc0fbebe2 snapshot: Factor out virDomainMomentDef class
Pull out the common parts of virDomainSnapshotDef that will be reused
for virDomainCheckpointDef into a new base class.  Adjust all callers
that use the direct fields (some of it is churn that disappears when
the next patch refactors virDomainSnapshotObj; oh well...).

Someday, I hope to switch this type to be a subclass of virObject, but
that requires a more thorough audit of cleanup paths, and besides
minimal incremental changes are easier to review.

As for the choice of naming:
I promised my teenage daughter Evelyn that I'd give her credit for her
contribution to this commit. I asked her "What would be a good name
for a base class for DomainSnapshot and DomainCheckpoint". After
explaining what a base class was (using the classic OOB Square and
Circle inherit from Shape), she came up with "DomainMoment", which is
way better than my initial thought of "DomainPointInTime" or
"DomainPIT".

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:34 -05:00
Eric Blake
55c2ab3e2b snapshot: Access snapshot def directly when needed
An upcoming patch will rework virDomainSnapshotObjList to be generic
for both snapshots and checkpoints; reduce the churn by adding a new
accessor virDomainSnapshotObjGetDef() which returns the
snapshot-specific definition even when the list is rewritten to
operate only on a base class, then using it at sites that that are
specific to snapshots.  Use VIR_STEAL_PTR when appropriate in the
affected lines.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:33 -05:00
Eric Blake
4819f54bd3 snapshot: Track current snapshot in virDomainSnapshotObjList
It is easier to track the current snapshot as part of the list of
snapshots. In particular, doing so lets us guarantee that the current
snapshot is cleared if that snapshot is removed from the list (rather
than depending on the caller to do so, and risking a use-after-free
problem, such as the one recently patched in 1db9d0efbf).  This
requires the addition of several new accessor functions, as well as a
useful return type for virDomainSnapshotObjListRemove().  A few error
handling sites that were previously setting vm->current_snapshot =
NULL can now be dropped, because the previous function call has now
done it already.  Also, qemuDomainRevertToSnapshot() was setting the
current vm twice, so keep only the one used on the success path.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:15:20 -05:00
Eric Blake
f105627992 snapshot: Drop virDomainSnapshotDef.current
The only use for the 'current' member of virDomainSnapshotDef was with
the PARSE/FORMAT_INTERNAL flag for controlling an internal-use
<active> element marking whether a particular snapshot definition was
current, and even then, only by the qemu driver on output, and by qemu
and test driver on input. But this duplicates vm->snapshot_current,
and gets in the way of potential simplifications to have qemu store a
single file for all snapshots rather than one file per snapshot.  Get
rid of the member by adding a bool* parameter during parse (ignored if
the PARSE_INTERNAL flag is not set), and by adding a new flag during
format (if FORMAT_INTERNAL is set, the value printed in <active>
depends on the new FORMAT_CURRENT).

Then update the qemu driver accordingly, which involves hoisting
assignments to vm->current_snapshot to occur prior to any point where
a snapshot XML file is written (although qemu kept
vm->current_snapshot and snapshot->def_current in sync by the end of
the function, they were not always identical in the middle of
functions, so the shuffling gets a bit interesting). Later patches
will clean up some of that confusing churn to vm->current_snapshot.

Note: even if later patches refactor qemu to no longer use
FORMAT_INTERNAL for output (by storing bulk snapshot XML instead), we
will always need PARSE_INTERNAL for input (because on upgrade, a new
libvirt still has to parse XML left from a previous libvirt).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:15:20 -05:00
Eric Blake
9b75154c07 snapshot: Break out virDomainSnapshotObjList into its own file
snapshot_conf.h was mixing three separate types: the snapshot
definition, the snapshot object, and the snapshot object list.
Separate out the snapshot object list code into its own file, and
update includes for affected clients.

This is just code motion, but done in preparation of sharing a lot of
the object list code with checkpoints.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-15 11:43:09 -05:00
Eric Blake
21b2651e72 snapshot: Export two functions prior to file split
The next patch will require access to the helper functions
virDomainSnapshotDefFormatInternal and
virDomainSnapshotRedefineValidate from two different files; make the
file split easier by exporting these functions.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-15 11:37:59 -05:00
Eric Blake
ca20690e9f snapshot: Break out virDomainSnapshotObj into its own file
snapshot_conf.h was mixing three separate types: the snapshot
definition, the snapshot object, and the snapshot object list.
Separate out the snapshot object code into its own file, which
includes moving a typedef to avoid circular inclusions.

Mostly straight code motion, although I fixed a comment along
the way, now that virDomainSnapshotForEachDescendent now
guarantees a topological visit (missed in b647d219).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-15 11:34:32 -05:00
Eric Blake
b647d2195d snapshots: Support topological visits
Wire up support for VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL in the
domain-agnostic support code.

Clients of snapshot_conf using virDomainSnapshotForEachDescendant()
are using a depth-first visit but with postfix visits of a given
node. Changing this to a prefix visit of the given node instantly
turns this into a topologically-ordered visit.  (A prefix
breadth-first visit would also be topologically sorted, but that
requires a queue while our recursion naturally has a stack).

With that change, we now always have a topological sort for
virDomainSnapshotListAllChildren() regardless of the new public API
flag. Then with one more tweak, we can also get a topological rather
than a faster random hash visit for virDomainListAllSnapshots(), by
doing a descendent walk from our internal metaroot (there, we let the
public API flag control behavior, because a topological sort DOES
require more stack and slightly more time).

Note that virDomainSnapshotForEach() still uses a random hash visit;
we could change that signature to take a tri-state for random, prefix,
or postfix visit if we ever had clients that cared about the
distinctions, but for now, none of the drivers seem to care.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-12 20:46:09 -05:00
Eric Blake
1b57269cbc snapshot: Add virDomainSnapshotObjListParse
Add a new function to make it possible to parse a list of snapshots
at once.  This is a counterpart to an earlier patch making it
possible to produce all snapshots in a single XML string, and
intentionally parses the same top-level element <snapshots> with
an optional attribute current='name'.

Note that since we know we started with no relations at all, and
since checking parent relationships per-snapshot is not viable as
we don't control which order the snapshots appear in, that we are
fine with doing a final pass to update all parent/child
relationships among the definitions.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:42:07 -06:00
Eric Blake
1e90fa89d1 snapshot: Split out virDomainSnapshotRedefineValidate helper
Pull out the portion of virDomainSnapshotRefinePrep() that deals
with definition sanity into a separate helper routine that can
be reused with bulk redefine, leaving behind only the code
specific to loop checking and in-place updates that are only
needed in single-definition handling.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 17:41:51 -06:00
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