Commit Graph

232 Commits

Author SHA1 Message Date
Markus Armbruster
7a309cc95b qom: Change object_get_canonical_path_component() not to malloc
object_get_canonical_path_component() returns a malloced copy of a
property name on success, null on failure.

19 of its 25 callers immediately free the returned copy.

Change object_get_canonical_path_component() to return the property
name directly.  Since modifying the name would be wrong, adjust the
return type to const char *.

Drop the free from the 19 callers become simpler, add the g_strdup()
to the other six.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200714160202.3121879-4-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
2020-07-21 16:23:43 +02:00
Eric Auger
db57fef1e2 qom: Introduce object_property_try_add_child()
object_property_add() does not allow object_property_try_add()
to gracefully fail as &error_abort is passed as an error handle.

However such failure can easily be triggered from the QMP shell when,
for instance, one attempts to create an object with an id that already
exists. This is achieved from the following call path:

qmp_object_add -> user_creatable_add_dict -> user_creatable_add_type ->
object_property_add_child -> object_property_add

For instance, from the qmp-shell, call twice:
object-add qom-type=memory-backend-ram id=mem1 props.size=1073741824
and QEMU aborts.

This behavior is undesired as a user/management application mistake
in reusing a property ID shouldn't result in loss of the VM and live
data within.

This patch introduces a new function, object_property_try_add_child()
which takes an error handle and turn object_property_try_add() into
a non-static one.

Now the call path becomes:

user_creatable_add_type -> object_property_try_add_child ->
object_property_try_add

and the error is returned gracefully to the QMP client.

(QEMU) object-add qom-type=memory-backend-ram id=mem2  props.size=4294967296
{"return": {}}
(QEMU) object-add qom-type=memory-backend-ram id=mem2  props.size=4294967296
{"error": {"class": "GenericError", "desc": "attempt to add duplicate property
'mem2' to object (type 'container')"}}

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Fixes: d2623129a7 ("qom: Drop parameter @errp of object_property_add() & friends")
Reviewed-by: Markus Armbruster <armbru@redhat.com>

Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200629193424.30280-2-eric.auger@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10 18:02:16 -04:00
Markus Armbruster
992861fb1e error: Eliminate error_propagate() manually
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  The previous two commits did that for sufficiently simple
cases with Coccinelle.  Do it for several more manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-37-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
af175e85f9 error: Eliminate error_propagate() with Coccinelle, part 2
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  The previous commit did that with a Coccinelle script I
consider fairly trustworthy.  This commit uses the same script with
the matching of return taken out, i.e. we convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
    }

This is unsound: @err could still be read between afterwards.  I don't
know how to express "no read of @err without an intervening write" in
Coccinelle.  Instead, I manually double-checked for uses of @err.

Suboptimal line breaks tweaked manually.  qdev_realize() simplified
further to placate scripts/checkpatch.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-36-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
668f62ec62 error: Eliminate error_propagate() with Coccinelle, part 1
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }

where nothing else needs @err.  Coccinelle script:

    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }

    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }

    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err

Not exactly elegant, I'm afraid.

The "when != lbl:" is necessary to avoid transforming

         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);

even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().

Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.

The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().

Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.

Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
b783f54d60 qom: Make functions taking Error ** return bool, not 0/-1
Just for consistency.  Also fix the example in object_set_props()'s
documentation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-31-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
778a2dc592 qom: Use returned bool to check for failure, Coccinelle part
The previous commit enables conversion of

    foo(..., &err);
    if (err) {
        ...
    }

to

    if (!foo(..., errp)) {
        ...
    }

for QOM functions that now return true / false on success / error.
Coccinelle script:

    @@
    identifier fun = {
        object_apply_global_props, object_initialize_child_with_props,
        object_initialize_child_with_propsv, object_property_get,
        object_property_get_bool, object_property_parse, object_property_set,
        object_property_set_bool, object_property_set_int,
        object_property_set_link, object_property_set_qobject,
        object_property_set_str, object_property_set_uint, object_set_props,
        object_set_propv, user_creatable_add_dict,
        user_creatable_complete, user_creatable_del
    };
    expression list args, args2;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err, args2);
    -    if (err)
    +    if (!fun(args, &err, args2))
         {
             ...
         }

Fails to convert hw/arm/armsse.c, because Coccinelle gets confused by
ARMSSE being used both as typedef and function-like macro there.
Convert manually.

Line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-29-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
6fd5bef10b qom: Make functions taking Error ** return bool, not void
See recent commit "error: Document Error API usage rules" for
rationale.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-28-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
5325cc34a2 qom: Put name parameter before value / visitor parameter
The object_property_set_FOO() setters take property name and value in
an unusual order:

    void object_property_set_FOO(Object *obj, FOO_TYPE value,
                                 const char *name, Error **errp)

Having to pass value before name feels grating.  Swap them.

Same for object_property_set(), object_property_get(), and
object_property_parse().

Convert callers with this Coccinelle script:

    @@
    identifier fun = {
        object_property_get, object_property_parse, object_property_set_str,
        object_property_set_link, object_property_set_bool,
        object_property_set_int, object_property_set_uint, object_property_set,
        object_property_set_qobject
    };
    expression obj, v, name, errp;
    @@
    -    fun(obj, v, name, errp)
    +    fun(obj, name, v, errp)

Chokes on hw/arm/musicpal.c's lcd_refresh() with the unhelpful error
message "no position information".  Convert that one manually.

Fails to convert hw/arm/armsse.c, because Coccinelle gets confused by
ARMSSE being used both as typedef and function-like macro there.
Convert manually.

Fails to convert hw/rx/rx-gdbsim.c, because Coccinelle gets confused
by RXCPU being used both as typedef and function-like macro there.
Convert manually.  The other files using RXCPU that way don't need
conversion.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-27-armbru@redhat.com>
[Straightforwad conflict with commit 2336172d9b "audio: set default
value for pcspk.iobase property" resolved]
2020-07-10 15:18:08 +02:00
Markus Armbruster
1c94a35164 qom: Use return values to check for error where that's simpler
When using the Error object to check for error, we need to receive it
into a local variable, then propagate() it to @errp.

Using the return value permits allows receiving it straight to @errp.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-26-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
90c69fb9fd qom: Rename qdev_get_type() to object_get_type()
Commit 2f262e06f0 lifted qdev_get_type() from qdev to object without
renaming it accordingly.  Do that now.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-23-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
62a35aaa31 qapi: Use returned bool to check for failure, Coccinelle part
The previous commit enables conversion of

    visit_foo(..., &err);
    if (err) {
        ...
    }

to

    if (!visit_foo(..., errp)) {
        ...
    }

for visitor functions that now return true / false on success / error.
Coccinelle script:

    @@
    identifier fun =~ "check_list|input_type_enum|lv_start_struct|lv_type_bool|lv_type_int64|lv_type_str|lv_type_uint64|output_type_enum|parse_type_bool|parse_type_int64|parse_type_null|parse_type_number|parse_type_size|parse_type_str|parse_type_uint64|print_type_bool|print_type_int64|print_type_null|print_type_number|print_type_size|print_type_str|print_type_uint64|qapi_clone_start_alternate|qapi_clone_start_list|qapi_clone_start_struct|qapi_clone_type_bool|qapi_clone_type_int64|qapi_clone_type_null|qapi_clone_type_number|qapi_clone_type_str|qapi_clone_type_uint64|qapi_dealloc_start_list|qapi_dealloc_start_struct|qapi_dealloc_type_anything|qapi_dealloc_type_bool|qapi_dealloc_type_int64|qapi_dealloc_type_null|qapi_dealloc_type_number|qapi_dealloc_type_str|qapi_dealloc_type_uint64|qobject_input_check_list|qobject_input_check_struct|qobject_input_start_alternate|qobject_input_start_list|qobject_input_start_struct|qobject_input_type_any|qobject_input_type_bool|qobject_input_type_bool_keyval|qobject_input_type_int64|qobject_input_type_int64_keyval|qobject_input_type_null|qobject_input_type_number|qobject_input_type_number_keyval|qobject_input_type_size_keyval|qobject_input_type_str|qobject_input_type_str_keyval|qobject_input_type_uint64|qobject_input_type_uint64_keyval|qobject_output_start_list|qobject_output_start_struct|qobject_output_type_any|qobject_output_type_bool|qobject_output_type_int64|qobject_output_type_null|qobject_output_type_number|qobject_output_type_str|qobject_output_type_uint64|start_list|visit_check_list|visit_check_struct|visit_start_alternate|visit_start_list|visit_start_struct|visit_type_.*";
    expression list args;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err);
    -    if (err)
    +    if (!fun(args, &err))
         {
             ...
         }

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-19-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Gerd Hoffmann
0f8198f1b2 object: qom module support
Little helper function to load modules on demand.  In most cases adding
module loading support for devices and other objects is just
s/object_class_by_name/module_object_class_by_name/ in the right spot.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20200624131045.14512-3-kraxel@redhat.com
2020-07-07 14:54:29 +02:00
Markus Armbruster
9fc7fc4d39 qom: Less verbose object_initialize_child()
All users of object_initialize_child() pass the obvious child size
argument.  Almost all pass &error_abort and no properties.  Tiresome.

Rename object_initialize_child() to
object_initialize_child_with_props() to free the name.  New
convenience wrapper object_initialize_child() automates the size
argument, and passes &error_abort and no properties.

Rename object_initialize_childv() to
object_initialize_child_with_propsv() for consistency.

Convert callers with this Coccinelle script:

    @@
    expression parent, propname, type;
    expression child, size;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, OBJECT(child), size, type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, child, size, type, &error_abort, NULL)

    @@
    expression parent, propname, type;
    expression child;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, child, sizeof(*child), type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, child, type)

    @@
    expression parent, propname, type;
    expression child;
    symbol error_abort;
    @@
    -    object_initialize_child(parent, propname, &child, sizeof(child), type, &error_abort, NULL)
    +    object_initialize_child(parent, propname, &child, type)

    @@
    expression parent, propname, type;
    expression child, size, err;
    expression list props;
    @@
    -    object_initialize_child(parent, propname, child, size, type, err, props)
    +    object_initialize_child_with_props(parent, propname, child, size, type, err, props)

Note that Coccinelle chokes on ARMSSE typedef vs. macro in
hw/arm/armsse.c.  Worked around by temporarily renaming the macro for
the spatch run.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
[Rebased: machine opentitan is new (commit fe0fe4735e)]
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-37-armbru@redhat.com>
2020-06-15 22:05:28 +02:00
Markus Armbruster
e8512dfa4d qom: Constify object_get_canonical_path{,_component}()'s parameter
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200527084754.7531-2-armbru@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-06-15 21:34:25 +02:00
Masahiro Yamada
e27a959581 qom/object: pass (Object *) to object_initialize_with_type()
object_new_with_type() already passes (Object *) pointer.
Avoid casting back and forth.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Message-Id: <20200512173104.2293073-1-masahiroy@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:58 -04:00
Masahiro Yamada
3d91293ed2 qom/object: simplify type_initialize_interface()
iface_impl->class is the same as new_iface. Make it more readable.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Message-Id: <20200512182501.2300530-1-masahiroy@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:58 -04:00
Masahiro Yamada
e5a0cc5e44 qom/object: factor out the initialization of hash table of properties
Properties are not related to the initialization of interfaces.

The initialization of the hash table can be moved after the if-block,
and unified.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Message-Id: <20200512172615.2291999-1-masahiroy@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:57 -04:00
Masahiro Yamada
ad195c8ff5 qom: remove index from object_resolve_abs_path()
You can advance 'parts' to track the current path fragment.
The 'index' parameter is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Message-Id: <20200510013235.954906-1-masahiroy@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:57 -04:00
Cédric Le Goater
4a39181db2 qom/object: Fix object_child_foreach_recursive() return value
When recursing, the return value of do_object_child_foreach() is not
taken into account.

Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Fixes: d714b8de77 ("qom: Add recursive version of object_child_for_each")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200404153340.164861-1-clg@kaod.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-10 12:09:35 -04:00
Philippe Mathieu-Daudé
688ffbb4f7 various: Remove unnecessary OBJECT() cast
The OBJECT() macro is defined as:

  #define OBJECT(obj) ((Object *)(obj))

Remove the unnecessary OBJECT() casts when we already know the
pointer is of Object type.

Patch created mechanically using spatch with this script:

  @@
  typedef Object;
  Object *o;
  @@
  -   OBJECT(o)
  +   o

Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: John Snow <jsnow@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200512070020.22782-3-f4bug@amsat.org>
[Trivial rebase conflict in hw/s390x/sclp.c resolved]
2020-05-15 07:08:14 +02:00
Markus Armbruster
df4fe0b291 qom: Drop @errp parameter of object_property_del()
Same story as for object_property_add(): the only way
object_property_del() can fail is when the property with this name
does not exist.  Since our property names are all hardcoded, failure
is a programming error, and the appropriate way to handle it is
passing &error_abort.  Most callers do that, the commit before
previous fixed one that didn't (and got the error handling wrong), and
the two remaining exceptions ignore errors.

Drop the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-05-15 07:08:14 +02:00
Markus Armbruster
d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00
Markus Armbruster
7eecec7d12 qom: Drop object_property_set_description() parameter @errp
object_property_set_description() and
object_class_property_set_description() fail only when property @name
is not found.

There are 85 calls of object_property_set_description() and
object_class_property_set_description().  None of them can fail:

* 84 immediately follow the creation of the property.

* The one in spapr_rng_instance_init() refers to a property created in
  spapr_rng_class_init(), from spapr_rng_properties[].

Every one of them still gets to decide what to pass for @errp.

51 calls pass &error_abort, 32 calls pass NULL, one receives the error
and propagates it to &error_abort, and one propagates it to
&error_fatal.  I'm actually surprised none of them violates the Error
API.

What are we gaining by letting callers handle the "property not found"
error?  Use when the property is not known to exist is simpler: you
don't have to guard the call with a check.  We haven't found such a
use in 5+ years.  Until we do, let's make life a bit simpler and drop
the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-8-armbru@redhat.com>
[One semantic rebase conflict resolved]
2020-05-15 07:06:49 +02:00
Markus Armbruster
7025188772 qom: Make all the object_property_add_FOO() return the property
Some object_property_add_FOO() return the newly added property, some
don't.  Clean that up.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-7-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster
44a17fe05a qom: Drop convenience method object_property_get_uint16List()
qom/object.c provides object_property_get_TYPE() and
object_property_set_TYPE() for a number of common types.  These are
all convenience wrappers around object_property_get_qobject() and
object_property_set_qobject().

Except for object_property_get_uint16List(), which is unusual in two ways:

* It bypasses object_property_get_qobject().  Fixable; the previous
  commit did it for object_property_get_enum())

* It stores the value through a parameter.  Its contract claims it
  returns the value, like the other functions do.  Also fixable.

Fixing is not worthwhile, though: object_property_get_uint16List() has
seen exactly one user in six years.

Convert the lone user to do its job with the generic
object_property_get_qobject(), and drop object_property_get_uint16List().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200505152926.18877-6-armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
[Commit message typo fixed]
2020-05-15 06:26:02 +02:00
Markus Armbruster
b555f89fcb qom: Simplify object_property_get_enum()
Reuse object_property_get_str().  Switches from the string to the
qobject visitor under the hood.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200505152926.18877-5-armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster
f73a32a514 qom: Drop object_property_del_child()'s unused parameter @errp
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-4-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster
ddfb0baaf2 qom: Clean up inconsistent use of gchar * vs. char *
Uses of gchar * in qom/object.h:

* ObjectProperty member @name

  Functions that take a property name argument all use char *.  Change
  the member to match.

* ObjectProperty member @type

  Functions that take a property type argument or return it all use
  char *.  Change the member to match.

* ObjectProperty member @description

  Functions that take a property description argument all use char *.
  Change the member to match.

* object_resolve_path_component() parameter @part

  Path components are property names.  Most callers pass char *
  arguments.  Change the parameter to match.  Adjust the few callers
  that pass gchar * to pass char *.

* Return value of object_get_canonical_path_component(),
  object_get_canonical_path()

  Most callers convert their return values right back to char *.
  Change the return value to match.  Adjust the few callers where that
  would add a conversion to gchar * to use char * instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-3-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster
975ac4559c qom: Clearer reference counting in object_initialize_childv()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-2-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Markus Armbruster
ea097dff0f qom: Simplify object_property_get_enum()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200424084338.26803-14-armbru@redhat.com>
2020-04-30 07:26:41 +02:00
Felipe Franciosi
836e1b3813 qom/object: enable setter for uint types
Traditionally, the uint-specific property helpers only offer getters.
When adding object (or class) uint types, one must therefore use the
generic property helper if a setter is needed (and probably duplicate
some code writing their own getters/setters).

This enhances the uint-specific property helper APIs by adding a
bitwise-or'd 'flags' field and modifying all clients of that API to set
this paramater to OBJ_PROP_FLAG_READ. This maintains the current
behaviour whilst allowing others to also set OBJ_PROP_FLAG_WRITE (or use
the more convenient OBJ_PROP_FLAG_READWRITE) in the future (which will
automatically install a setter). Other flags may be added later.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 23:02:23 +01:00
Marc-André Lureau
b77ade9bb3 object: return self in object_ref()
This allow for simpler assignment with ref: foo = object_ref(bar)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200110153039.1379601-19-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
9859facc04 object: release all props
Class properties may have to release resources when the object is
destroyed. Let's use the existing release() callback for that, but
class properties must not release ObjectProperty, as it can be shared
by various instances.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-18-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
840ecdfbf9 object: add object_class_property_add_link()
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-17-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
4a8d57989b object: express const link with link property
Let's not mix child property and link property callbacks, as this is
confusing, use LinkProperty with DIRECT flag to hold the target pointer.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-16-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
9941d37b4d object: add direct link flag
Allow the link property to hold the pointer to the target, instead of
indirectly through another variable.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-15-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
36854207f0 object: rename link "child" to "target"
A child property is a different kind of property. Let's use "target"
for the link target.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-14-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:14 +01:00
Marc-André Lureau
8770bafdc9 object: check strong flag with &
The following patch is going to introduce more flags.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-13-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:13 +01:00
Marc-André Lureau
fc4fe712ae object: do not free class properties
The release callback is called during object_property_del_all(), on a
live instance. But class properties are common among all
instances. It is not currently called, because we don't release
classes, but it would not be correct if we did.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:13 +01:00
Marc-André Lureau
0e76ed0a5d object: add object_property_set_default
Add a default value to ObjectProperty and an implementation of
ObjectPropertyInit that uses it.  This will make it easier to show the
default in help messages.

Also provide convenience functions object_property_set_default_{bool,
str, int, uint}().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-11-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:13 +01:00
Marc-André Lureau
a3a162113e object: make object_class_property_add* return property
This will help calling other ObjectProperty associated functions
easily after.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-9-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:13 +01:00
Marc-André Lureau
2a1be4b348 object: add class property initializer
This callback is used to set default value in following patch "object:
add object_property_set_defaut_{bool,str,int,uint}()".

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:12 +01:00
Marc-André Lureau
ba806ffbdf object: avoid extra class property key duplication
Like object properties, no need to duplicate property name, as it is
owned already by ObjectProperty value.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-6-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:12 +01:00
Marc-André Lureau
d5e633fc97 object: add extra sanity checks
Type system checked that children class_size >= parent class_size, but
not instances. Fix that.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200110153039.1379601-2-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:12 +01:00
Philippe Mathieu-Daudé
89d337fdd2 qom/object: Display more helpful message when a parent is missing
QEMU object model is scarse in documentation. Some calls are
recursive, and it might be hard to figure out even trivial issues.

We can avoid developers to waste time in a debugging session by
displaying a simple error message.

This commit is also similar to e02bdf1cec ("Display more helpful
message when an object type is missing").

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200121110349.25842-7-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:11 +01:00
Philippe Mathieu-Daudé
a9ee3a9e1c qom/object: Display more helpful message when an interface is missing
When adding new devices implementing QOM interfaces, we might
forgot to add the Kconfig dependency that pulls the required
objects in when building.

Since QOM dependencies are resolved at runtime, we don't get any
link-time failures, and QEMU aborts while starting:

  $ qemu ...
  Segmentation fault (core dumped)

  (gdb) bt
  #0  0x00007ff6e96b1e35 in raise () from /lib64/libc.so.6
  #1  0x00007ff6e969c895 in abort () from /lib64/libc.so.6
  #2  0x00005572bc5051cf in type_initialize (ti=0x5572be6f1200) at qom/object.c:323
  #3  0x00005572bc505074 in type_initialize (ti=0x5572be6f1800) at qom/object.c:301
  #4  0x00005572bc505074 in type_initialize (ti=0x5572be6e48e0) at qom/object.c:301
  #5  0x00005572bc506939 in object_class_by_name (typename=0x5572bc56109a) at qom/object.c:959
  #6  0x00005572bc503dd5 in cpu_class_by_name (typename=0x5572bc56109a, cpu_model=0x5572be6d9930) at hw/core/cpu.c:286

Since the caller has access to the qdev parent/interface names,
we can simply display them to avoid starting a debugger:

  $ qemu ...
  qemu: missing interface 'fancy-if' for object 'fancy-dev'
  Aborted (core dumped)

This commit is similar to e02bdf1cec ("Display more helpful message
when an object type is missing").

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200118162348.17823-1-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:07 +01:00
Paolo Bonzini
3c75e12ea6 qom: add object_new_with_class
Similar to CPU and machine classes, "-accel" class names are mangled,
so we have to first get a class via accel_find and then instantiate it.
Provide a new function to instantiate a class without going through
object_class_get_name, and use it for CPUs and machines already.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-17 19:32:26 +01:00
Paolo Bonzini
1fff3c206f qom: introduce object_register_sugar_prop
Similar to the existing "-rtc driftfix" option, we will convert some
legacy "-machine" command line options to global properties on accelerators.
Because accelerators are not devices, we cannot use qdev_prop_register_global.
Instead, provide a slot in the generic object_compat_props arrays for
command line syntactic sugar.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-12-17 19:32:26 +01:00
Greg Kurz
d55e937d3e qom: Fix error message in object_class_property_add()
The error message in object_class_property_add() was copied from
object_property_add() in commit 16bf7f522a. Clarify that it is
about a class, not an object.

While here, have the format string in both functions to fit in a
single line for better grep-ability, despite the checkpatch warning.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <157287383591.234942.311840593519058490.stgit@bahia.tlslab.ibm.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-11-12 10:33:02 +01:00