Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Conversion of docs/devel/qapi-code-gen.txt to ReST left several
dangling references behind. Fix them to point to
docs/devel/qapi-code-gen.rst.
Fixes: f7aa076dbd (docs: convert qapi-code-gen.txt to ReST)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240120095327.666239-4-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
StringOutputVisitor crashes when it visits a struct because
->start_struct() is NULL.
Show "<omitted>" instead of crashing. This is necessary because the
virtio-blk-pci iothread-vq-mapping parameter that I'd like to introduce
soon is a list of IOThreadMapping structs.
This patch is a quick fix to solve the crash, but the long-term solution
is replacing StringOutputVisitor with something that can handle the full
gamut of values in QEMU.
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20231212134934.500289-1-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Variables declared in macros can shadow other variables. Much of the
time, this is harmless, e.g.:
#define _FDT(exp) \
do { \
int ret = (exp); \
if (ret < 0) { \
error_report("error creating device tree: %s: %s", \
#exp, fdt_strerror(ret)); \
exit(1); \
} \
} while (0)
Harmless shadowing in h_client_architecture_support():
target_ulong ret;
[...]
ret = do_client_architecture_support(cpu, spapr, vec, fdt_bufsize);
if (ret == H_SUCCESS) {
_FDT((fdt_pack(spapr->fdt_blob)));
[...]
}
return ret;
However, we can get in trouble when the shadowed variable is used in a
macro argument:
#define QOBJECT(obj) ({ \
typeof(obj) o = (obj); \
o ? container_of(&(o)->base, QObject, base) : NULL; \
})
QOBJECT(o) expands into
({
---> typeof(o) o = (o);
o ? container_of(&(o)->base, QObject, base) : NULL;
})
Unintended variable name capture at --->. We'd be saved by
-Winit-self. But I could certainly construct more elaborate death
traps that don't trigger it.
To reduce the risk of trapping ourselves, we use variable names in
macros that no sane person would use elsewhere. Here's our actual
definition of QOBJECT():
#define QOBJECT(obj) ({ \
typeof(obj) _obj = (obj); \
_obj ? container_of(&(_obj)->base, QObject, base) : NULL; \
})
Works well enough until we nest macro calls. For instance, with
#define qobject_ref(obj) ({ \
typeof(obj) _obj = (obj); \
qobject_ref_impl(QOBJECT(_obj)); \
_obj; \
})
the expression qobject_ref(obj) expands into
({
typeof(obj) _obj = (obj);
qobject_ref_impl(
({
---> typeof(_obj) _obj = (_obj);
_obj ? container_of(&(_obj)->base, QObject, base) : NULL;
}));
_obj;
})
Unintended variable name capture at --->.
The only reliable way to prevent unintended variable name capture is
-Wshadow.
One blocker for enabling it is shadowing hiding in function-like
macros like
qdict_put(dict, "name", qobject_ref(...))
qdict_put() wraps its last argument in QOBJECT(), and the last
argument here contains another QOBJECT().
Use dark preprocessor sorcery to make the macros that give us this
problem use different variable names on every call.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230921121312.1301864-8-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
There should be no paths from a coroutine_fn to aio_poll, however in
practice coroutine_mixed_fn will call aio_poll in the !qemu_in_coroutine()
path. By marking mixed functions, we can track accurately the call paths
that execute entirely in coroutine context, and find more missing
coroutine_fn markers. This results in more accurate checks that
coroutine code does not end up blocking.
If the marking were extended transitively to all functions that call
these ones, static analysis could be done much more efficiently.
However, this is a start and makes it possible to use vrc's path-based
searches to find potential bugs where coroutine_fns call blocking functions.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This can help debugging issues or develop, when error handling is
introduced.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-6-marcandre.lureau@redhat.com>
The QERR_ macros are leftovers from the days of "rich" error objects.
We've been trying to reduce their remaining use.
The stubbed out Rocker monitor commands are the last remaining users
of QERR_FEATURE_DISABLED. They fail like this:
(qemu) info rocker mumble
Error: The feature 'rocker' is not enabled
The real rocker commands fail like this when the named object doesn't
exist:
Error: rocker mumble not found
If that's good enough when Rocker is enabled, then it's good enough
when it's disabled, so replace QERR_FEATURE_DISABLED with that, and
drop the macro.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230207075115.1525-13-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
replay_add_blocker() takes an Error *. All callers pass one created
like this:
error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED, "some feature");
Folding this into replay_add_blocker() simplifies the callers, losing
a bit of generality we haven't needed in more than six years.
Since there are no other uses of macro QERR_REPLAY_NOT_SUPPORTED,
replace the remaining one by its expansion, and drop the macro.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230207075115.1525-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Move them where they belong, since the functions are implemented in block-qdict.c.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220420132624.2439741-25-marcandre.lureau@redhat.com>
Need wrappers for qobject_unref() calls, which is a macro.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-10-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
This provides a foundation on which to convert simple HMP commands to
use QMP. The QMP implementation will generate formatted text targeted
for human consumption, returning it in the HumanReadableText data type.
The HMP command handler will simply print out the formatted string
within the HumanReadableText data type. Since this will be an entirely
formulaic action in the case of HMP commands taking no arguments, a
custom command handler is provided.
Thus instead of registering a 'cmd' callback for the HMP command, a
'cmd_info_hrt' callback is provided, which will simply be a pointer
to the QMP implementation.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
New option parameters unstable-input and unstable-output set policy
for unstable interfaces just like deprecated-input and
deprecated-output set policy for deprecated interfaces (see commit
6dd75472d5 "qemu-options: New -compat to set policy for deprecated
interfaces"). This is intended for testing users of the management
interfaces. It is experimental.
For now, this covers only syntactic aspects of QMP, i.e. stuff tagged
with feature 'unstable'. We may want to extend it to cover semantic
aspects, or the command line.
Note that there is no good way for management application to detect
presence of these new option parameters: they are not visible output
of query-qmp-schema or query-command-line-options. Tolerable, because
it's meant for testing. If running with -compat fails, skip the test.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-10-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Doc comments fixed up]
The code to check policy for handling deprecated input is triplicated.
Factor it out into compat_policy_input_ok() before I mess with it in
the next commit.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211028102520.747396-9-armbru@redhat.com>
[Policy code moved from qmp-dispatch.c to qapi-util.c to make visitors
link without qmp-dispatch.o]
The code to check enumeration value policy can see special feature
flag 'deprecated' in QEnumLookup member flags[value]. I want to make
feature flag 'unstable' visible there as well, so I can add policy for
it.
Instead of extending flags[], replace it by @special_features (a
bitset of QapiSpecialFeature), because that's how special features get
passed around elsewhere.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-8-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
The code to check command policy can see special feature flag
'deprecated' as command flag QCO_DEPRECATED. I want to make feature
flag 'unstable' visible there as well, so I can add policy for it.
To let me make it visible, add member @special_features (a bitset of
QapiSpecialFeature) to QmpCommand, and adjust the generator to pass it
through qmp_register_command(). Then replace "QCO_DEPRECATED in
@flags" by QAPI_DEPRECATED in @special_features", and drop
QCO_DEPRECATED.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-7-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The generated visitor functions call visit_deprecated_accept() and
visit_deprecated() when visiting a struct member with special feature
flag 'deprecated'. This makes the feature flag visible to the actual
visitors. I want to make feature flag 'unstable' visible there as
well, so I can add policy for it.
To let me make it visible, replace these functions by
visit_policy_reject() and visit_policy_skip(), which take the member's
special features as an argument. Note that the new functions have the
opposite sense, i.e. the return value flips.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20211028102520.747396-6-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Unbreak forward visitor]
New enum QapiSpecialFeature enumerates the special feature flags.
New helper gen_special_features() returns code to represent a
collection of special feature flags as a bitset.
The next few commits will put them to use.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-5-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-4-armbru@redhat.com>
This copies the code implementing the policy from qapi/qmp-dispatch.c
to qapi/qobject-input-visitor.c. Tolerable, but if we acquire more
copies, we should look into factoring them out.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <20211025042405.3762351-5-armbru@redhat.com>
The next commit needs to access compat policy from the generic visitor
core. Move it there from qobject input and output visitor.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20211025042405.3762351-4-armbru@redhat.com>
This new adaptor visitor takes a single field of the adaptee, and exposes it
with a different name.
This will be used for QOM alias properties. Alias targets can of course
have a different name than the alias property itself (e.g. a machine's
pflash0 might be an alias of a property named 'drive'). When the target's
getter or setter invokes the visitor, it will use a different name than
what the caller expects, and the visitor will not be able to find it
(or will consume erroneously).
The solution is for alias getters and setters to wrap the incoming
visitor, and forward the sole field that the target is expecting while
renaming it appropriately.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let -readconfig support parsing command line options into QDict or
QemuOpts. This will be used to add back support for objects in
-readconfig.
Cc: Markus Armbruster <armbru@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210524105752.3318299-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Several issues has been reported for query-netdev info
series. Consider it's late in the rc, this reverts commit
a0724776c5.
Signed-off-by: Jason Wang <jasowang@redhat.com>
This policy rejects deprecated input, and thus permits "testing the
future". Implement it for QMP command arguments: reject commands with
deprecated ones. Example: when QEMU is run with -compat
deprecated-input=reject, then
{"execute": "eject", "arguments": {"device": "cd"}}
fails like this
{"error": {"class": "GenericError", "desc": "Deprecated parameter 'device' disabled by policy"}}
When the deprecated parameter is removed, the error will change to
{"error": {"class": "GenericError", "desc": "Parameter 'device' is unexpected"}}
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210318155519.1224118-11-armbru@redhat.com>
This policy rejects deprecated input, and thus permits "testing the
future". Implement it for QMP commands: make deprecated ones fail.
Example: when QEMU is run with -compat deprecated-input=reject, then
{"execute": "query-cpus"}
fails like this
{"error": {"class": "CommandNotFound", "desc": "Deprecated command query-cpus disabled by policy"}}
When the deprecated command is removed, the error will change to
{"error": {"class": "CommandNotFound", "desc": "The command query-cpus has not been found"}}
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210318155519.1224118-10-armbru@redhat.com>
This policy suppresses deprecated bits in output, and thus permits
"testing the future". Implement it for QMP command results. Example:
when QEMU is run with -compat deprecated-output=hide, then
{"execute": "query-cpus-fast"}
yields
{"return": [{"thread-id": 9805, "props": {"core-id": 0, "thread-id": 0, "socket-id": 0}, "qom-path": "/machine/unattached/device[0]", "cpu-index": 0, "target": "x86_64"}]}
instead of
{"return": [{"arch": "x86", "thread-id": 22436, "props": {"core-id": 0, "thread-id": 0, "socket-id": 0}, "qom-path": "/machine/unattached/device[0]", "cpu-index": 0, "target": "x86_64"}]}
Note the suppression of deprecated member "arch".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210318155519.1224118-4-armbru@redhat.com>
New option -compat lets you configure what to do when deprecated
interfaces get used. This is intended for testing users of the
management interfaces. It is experimental.
-compat deprecated-input=<input-policy> configures what to do when
deprecated input is received. Input policy can be "accept" (accept
silently), or "reject" (reject the request with an error).
-compat deprecated-output=<out-policy> configures what to do when
deprecated output is sent. Output policy can be "accept" (pass on
unchanged), or "hide" (filter out the deprecated parts).
Default is "accept". Policies other than "accept" are implemented
later in this series.
For now, -compat covers only syntactic aspects of QMP, i.e. stuff
tagged with feature 'deprecated'. We may want to extend it to cover
semantic aspects, CLI, and experimental features.
Note that there is no good way for management application to detect
presence of -compat: it's not visible output of query-qmp-schema or
query-command-line-options. Tolerable, because it's meant for
testing. If running with -compat fails, skip the test.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210318155519.1224118-3-armbru@redhat.com>
qmp_disable_command() now takes an optional error string to return a
more explicit error message.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1928806
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
*fix up 80+ char line
Signed-off-by: Michael Roth <michael.roth@amd.com>
Replace usage of legacy field info_str of NetClientState for backend
network devices with QAPI NetdevInfo stored_config that already used
in QMP query-netdev.
This change increases the detail of the "info network" output and takes
a more general approach to composing the output.
NIC and hubports still use legacy info_str field.
Signed-off-by: Alexey Kirillov <lekiravi@yandex-team.ru>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Setting errp = NULL is wrong: the automatic error propagation still
propagates the dangling pointer _auto_errp_prop.local_err. We need to
set *errp = NULL to clear the dangling pointer.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210125132635.1253219-1-armbru@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Similar to the existing QAPI_LIST_PREPEND, but designed for use where
we want to preserve insertion order. Callers will be added in
upcoming patches. Note the difference in signature: PREPEND takes
List*, APPEND takes List**.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210113221013.390592-4-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The functions to modify a QString's string are all unused now. Drop
them, and make the string immutable. Saves 16 bytes per QString on my
system.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-21-armbru@redhat.com>
Commit 8118f0950f "migration: Append JSON description of migration
stream" needs a JSON writer. The existing qobject_to_json() wasn't a
good fit, because it requires building a QObject to convert. Instead,
migration got its very own JSON writer, in commit 190c882ce2 "QJSON:
Add JSON writer". It tacitly limits numbers to int64_t, and strings
contents to characters that don't need escaping, unlike
qobject_to_json().
The previous commit factored the JSON writer out of qobject_to_json().
Replace migration's JSON writer by it.
Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-17-armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We have two JSON writers written in C: qobject/qjson.c provides
qobject_to_json(), and migration/qjson.c provides a more low level
imperative interface. They don't share code. The latter tacitly
limits numbers to int64_t, and strings contents to characters that
don't need escaping.
Factor out qobject_to_json()'s JSON writer as qobject/json-writer.c.
Straightforward, except for numbers: since the writer is to be
independent of QObject, it can't use qnum_to_string(). Open-code it
instead. This is actually an improvement of sorts, because it
liberates qnum_to_string() from JSON's needs: its JSON-related FIXMEs
move to the JSON writer, where they belong.
The next commit will replace migration/qjson.c.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-16-armbru@redhat.com>
No users left outside tests/, and the ones in tests/ can just as well
use qstring_get_str(). Do that, and drop the function.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-14-armbru@redhat.com>
This reverts commit 164c374b75.
A free function for a reference-counted object is in bad taste.
Fortunately, this one is now also unused. Drop it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-7-armbru@redhat.com>
qobject_to_json() and qobject_to_json_pretty() build a GString, then
covert it to QString. Just one of the callers actually needs a
QString: qemu_rbd_parse_filename(). A few others need a string they
can modify: qmp_send_response(), qga's send_response(), to_json_str(),
and qmp_fd_vsend_fds(). The remainder just need a string.
Change qobject_to_json() and qobject_to_json_pretty() to return the
GString.
qemu_rbd_parse_filename() now has to convert to QString. All others
save a QString temporary. to_json_str() actually becomes a bit
simpler, because GString provides more convenient modification
functions.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-6-armbru@redhat.com>
QString supports modifying its string, but it's quite limited: you can
only append. The remaining callers use it for building an initial
string, never for modifying it later.
Use of GString for building the initial string is actually more
convenient here. Change qobject_to_json() & friends to do that.
Once all such uses are replaced this way, QString can become immutable.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-5-armbru@redhat.com>
The preconfig state is only used if -incoming is not specified, which
makes the RunState state machine more tricky than it need be. However
there is already an equivalent condition which works even with -incoming,
namely qdev_hotplug. Use it instead of a separate runstate.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
client_migrate_info reports spice_server_migrate_connect() failure as
"An undefined error has occurred". Improve to "Could not set up
display for migration".
QERR_UNDEFINED_ERROR is now unused. Drop.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113082626.2725812-6-armbru@redhat.com>
set_passwd and expire_password reject invalid "protocol" with "Invalid
parameter 'protocol'". Misleading; the parameter is valid, its value
isn't. Improve to "Parameter 'protocol' expects 'vnc' or 'spice'".
expire_password fails with "Could not set password". Misleading;
improve to "Could not set password expire time".
QERR_SET_PASSWD_FAILED is now unused. Drop.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113082626.2725812-5-armbru@redhat.com>
block-commit defaults @base-node to the deepest backing image. When
there is none, it fails with "Base 'NULL' not found". Improve to
"There is no backing image".
block-commit and block-stream reject a @base argument that doesn't
resolve with "Base 'BASE' not found". Commit 6b33f3ae8b "qemu-img:
Improve commit invalid base message" improved this message in
qemu-img. Improve it here, too: "Can't find '%s' in the backing
chain".
QERR_BASE_NOT_FOUND is now unused. Drop.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113082626.2725812-4-armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
