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

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>

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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)

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>

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qdev: Use returned bool to check for qdev_realize() etc. failure

Convert

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

to

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

for qdev_realize(),

qdev: Use returned bool to check for qdev_realize() etc. failure

Convert

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

to

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

for qdev_realize(), qdev_realize_and_unref(), qbus_realize() and their
wrappers isa_realize_and_unref(), pci_realize_and_unref(),
sysbus_realize(), sysbus_realize_and_unref(), usb_realize_and_unref().
Coccinelle script:

@@
identifier fun = {
isa_realize_and_unref, pci_realize_and_unref, qbus_realize,
qdev_realize, qdev_realize_and_unref, sysbus_realize,
sysbus_realize_and_unref, usb_realize_and_unref
};
expression list args, args2;
typedef Error;
Error *err;
@@
- fun(args, &err, args2);
- if (err)
+ if (!fun(args, &err, args2))
{
...
}

Chokes on hw/arm/musicpal.c's lcd_refresh() with the unhelpful error
message "no position information". Nothing to convert there; skipped.

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.

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>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200707160613.848843-5-armbru@redhat.com>

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sysbus: Convert qdev_set_parent_bus() use with Coccinelle, part 3

These are init/realize pairs produced by the previous commit's
Coccinelle script where the argument test doesn't quite match. They

sysbus: Convert qdev_set_parent_bus() use with Coccinelle, part 3

These are init/realize pairs produced by the previous commit's
Coccinelle script where the argument test doesn't quite match. They
need even more careful review.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-50-armbru@redhat.com>

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sysbus: Convert qdev_set_parent_bus() use with Coccinelle, part 2

This is the same transformation as in the previous commit, except
sysbus_init_child_obj() and realize are too separated for the comm

sysbus: Convert qdev_set_parent_bus() use with Coccinelle, part 2

This is the same transformation as in the previous commit, except
sysbus_init_child_obj() and realize are too separated for the commit's
Coccinelle script to handle, typically because sysbus_init_child_obj()
is in a device's instance_init() method, and the matching realize is
in its realize() method.

Perhaps a Coccinelle wizard could make it transform that pattern, but
I'm just a bungler, and the best I can do is transforming the two
separate parts separately:

@@
expression errp;
expression child;
symbol true;
@@
- object_property_set_bool(OBJECT(child), true, "realized", errp);
+ sysbus_realize(SYS_BUS_DEVICE(child), errp);
// only correct with a matching sysbus_init_child_obj() transformation!

@@
expression errp;
expression child;
symbol true;
@@
- object_property_set_bool(child, true, "realized", errp);
+ sysbus_realize(SYS_BUS_DEVICE(child), errp);
// only correct with a matching sysbus_init_child_obj() transformation!

@@
expression child;
@@
- qdev_init_nofail(DEVICE(child));
+ sysbus_realize(SYS_BUS_DEVICE(child), &error_fatal);
// only correct with a matching sysbus_init_child_obj() transformation!

@@
expression child;
expression dev;
@@
dev = DEVICE(child);
...
- qdev_init_nofail(dev);
+ sysbus_realize(SYS_BUS_DEVICE(dev), &error_fatal);
// only correct with a matching sysbus_init_child_obj() transformation!

@@
expression child;
identifier dev;
@@
DeviceState *dev = DEVICE(child);
...
- qdev_init_nofail(dev);
+ sysbus_realize(SYS_BUS_DEVICE(dev), &error_fatal);
// only correct with a matching sysbus_init_child_obj() transformation!

@@
expression parent, name, size, type;
expression child;
symbol true;
@@
- sysbus_init_child_obj(parent, name, child, size, type);
+ sysbus_init_child_XXX(parent, name, child, size, type);

@@
expression parent, propname, type;
expression child;
@@
- sysbus_init_child_XXX(parent, propname, child, sizeof(*child), type)
+ object_initialize_child(parent, propname, child, type)

@@
expression parent, propname, type;
expression child;
@@
- sysbus_init_child_XXX(parent, propname, &child, sizeof(child), type)
+ object_initialize_child(parent, propname, &child, type)

This script is *unsound*: we need to manually verify init and realize
conversions are properly paired.

This commit has only the pairs where object_initialize_child()'s
@child and sysbus_realize()'s @dev argument text match exactly within
the same source file.

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>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-49-armbru@redhat.com>

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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
hardc

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]

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cpu/arm11mpcore: Set number of GIC priority bits to 4

The GIC built into the ARM11MPCore is always implemented with 4
priority bits; set the GIC property accordingly.

Signed-off-by: Sai Pavan Boddu

cpu/arm11mpcore: Set number of GIC priority bits to 4

The GIC built into the ARM11MPCore is always implemented with 4
priority bits; set the GIC property accordingly.

Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1582537164-764-4-git-send-email-sai.pavan.boddu@xilinx.com
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: tweaked commit message]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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cpu/a9mpcore: Set number of GIC priority bits to 5

All A9 CPUs have a GIC with 5 bits of priority.

Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Reviewed-by: Peter Maydell <peter.mayd

cpu/a9mpcore: Set number of GIC priority bits to 5

All A9 CPUs have a GIC with 5 bits of priority.

Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1582537164-764-3-git-send-email-sai.pavan.boddu@xilinx.com
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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