Commit Graph

231 Commits

Author SHA1 Message Date
Peter Maydell 5fdb6cd272 hw/core/qdev: Simplify legacy_reset handling
Now that all devices which still implement a the legacy reset method
register it via device_class_legacy_reset(), we can simplify the
handling of these devices.  Instead of using the complex
Resettable::get_transitional_function machinery, we register a hold
phase method which invokes the DeviceClass::legacy_reset method.

This will allow us to remove all the get_transitional_function
handling from resettable.c.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240830145812.1967042-11-peter.maydell@linaro.org
2024-09-13 15:31:45 +01:00
Peter Maydell b5fe9bf296 hw: Remove device_phases_reset()
Currently we have transitional machinery between legacy reset
and three phase reset that works in two directions:
 * if you invoke three phase reset on a device which has set
   the DeviceClass::legacy_reset method, we detect this in
   device_get_transitional_reset() and arrange that we call
   the legacy_reset method during the hold phase of reset
 * if you invoke legacy reset on a device which implements
   three phase reset, the default legacy_reset method is
   device_phases_reset(), which does a three-phase reset
   of the device

However, we have now eliminated all the places which could invoke
legacy reset on a device, which means that the function
device_phases_reset() is never called -- it serves only as the value
of DeviceClass::legacy_reset that indicates that the subclass never
overrode the legacy reset method.  So we can delete it, and instead
check for legacy_reset != NULL.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240830145812.1967042-10-peter.maydell@linaro.org
2024-09-13 15:31:45 +01:00
Peter Maydell 1000872dde hw: Rename DeviceClass::reset field to legacy_reset
Rename the DeviceClass::reset field to legacy_reset; this is helpful
both in flagging up that it's best not used in new code and in
making it easy to search for where it's being used still.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240830145812.1967042-9-peter.maydell@linaro.org
2024-09-13 15:31:45 +01:00
Peter Maydell e3d0814368 hw: Use device_class_set_legacy_reset() instead of opencoding
Use device_class_set_legacy_reset() instead of opencoding an
assignment to DeviceClass::reset. This change was produced
with:
 spatch --macro-file scripts/cocci-macro-file.h \
    --sp-file scripts/coccinelle/device-reset.cocci \
    --keep-comments --smpl-spacing --in-place --dir hw

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240830145812.1967042-8-peter.maydell@linaro.org
2024-09-13 15:31:44 +01:00
Peter Maydell 134e0944f4 hw: Define new device_class_set_legacy_reset()
Define a device_class_set_legacy_reset() function which
sets the DeviceClass::reset field. This serves two purposes:
 * it makes it clearer to the person writing code that
   DeviceClass::reset is now legacy and they should look for
   the new alternative (which is Resettable)
 * it makes it easier to rename the reset field (which in turn
   makes it easier to find places that call it)

The Coccinelle script can be used to automatically convert code that
was doing an open-coded assignment to DeviceClass::reset to call
device_class_set_legacy_reset() instead.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240830145812.1967042-7-peter.maydell@linaro.org
2024-09-13 15:31:44 +01:00
Peter Maydell 5313a0a41e hw: Remove device_class_set_parent_reset()
There are no callers of device_class_set_parent_reset() left in the tree,
as they've all been converted to use three-phase reset and the
corresponding resettable_class_set_parent_phases() function.
Remove device_class_set_parent_reset().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240830145812.1967042-5-peter.maydell@linaro.org
2024-09-13 15:31:43 +01:00
Peter Maydell ad80e36744 hw, target: Add ResetType argument to hold and exit phase methods
We pass a ResetType argument to the Resettable class enter
phase method, but we don't pass it to hold and exit, even though
the callsites have it readily available. This means that if
a device cared about the ResetType it would need to record it
in the enter phase method to use later on. Pass the type to
all three of the phase methods to avoid having to do that.

Commit created with

  for dir in hw target include; do \
      spatch --macro-file scripts/cocci-macro-file.h \
             --sp-file scripts/coccinelle/reset-type.cocci \
             --keep-comments --smpl-spacing --in-place \
             --include-headers --dir $dir; done

and no manual edits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Luc Michel <luc.michel@amd.com>
Message-id: 20240412160809.1260625-5-peter.maydell@linaro.org
2024-04-25 10:21:06 +01:00
Philippe Mathieu-Daudé f95b25c37e qapi: Inline and remove QERR_DEVICE_NO_HOTPLUG definition
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:

  /*
   * These macros will go away, please don't use
   * in new code, and do not add new ones!
   */

Mechanical transformation using sed, and manual cleanup.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-5-armbru@redhat.com>
2024-04-24 09:50:58 +02:00
Manos Pitsidianakis 956ef49990 hw/core/qdev.c: add qdev_get_human_name()
Add a simple method to return some kind of human readable identifier for
use in error messages.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-id: 8b566bfced98ae44be1fcc1f8e7215f0c3393aa1.1706598705.git.manos.pitsidianakis@linaro.org
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2024-01-30 16:19:00 -05:00
Philippe Mathieu-Daudé 2d2f2507c6 hw/qdev: Constify DeviceState* argument of qdev_get_parent_bus()
The structure is accessed read-only by qdev_get_parent_bus().

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230212224730.51438-2-philmd@linaro.org>
2023-02-27 22:29:01 +01:00
Peter Maydell c3141e21e3 hw: Remove device_legacy_reset()
The device_legacy_reset() function is now not used anywhere, so we
can remove the implementation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-12-16 15:55:32 +00:00
Peter Maydell e5e887c73b qdev: Remove qdev_reset_all() and qbus_reset_all()
Remove the qdev_reset_all() and qbus_reset_all() functions, now we
have moved all the callers over to the new device_cold_reset() and
bus_cold_reset() functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-12-16 15:55:32 +00:00
Peter Maydell 48804eebd4 Miscellaneous patches for 2022-12-14
-----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEENUvIs9frKmtoZ05fOHC0AOuRhlMFAmOZ6lYSHGFybWJydUBy
 ZWRoYXQuY29tAAoJEDhwtADrkYZT6VEQAKynjWh3AIZ4/qOgrVqsP0oRspevLmfH
 BbuGoldjYpEE7RbwuCaZalZ7iy7TcSySxnPfUDVsFHd7NWffJVjwKHifGC0D/Ez0
 +Ggyb1CBebN+mS7t+BNFUHdMM+wxFIlHwg4f4aTFbn2o0HKgj2a8tcNzNRonZbfa
 xURnvbD4G4u0VZEc3Jak+x193xbOJFsuuWq0BZnDuNk+XqjyW2RwfpXLPJVk+82a
 4uy/YgYuqXUqBeULwcJj+shBL4SXR9GyajTFMS64przSUle0ADUmXkPtaS2agV7e
 Pym/UQuAcxvNyw34fJsiMZxx6rZI9YU30jQUMRLoYcPRR/Q/aiPeiiHtiD6Kaid7
 IfOeH/EArXaQRFpD89xj4YcaTnRLQOEj0NXgXvAbQf6eD8JYyao/S/0lCsPZEoA2
 nibLqEQ25ncDNXoSomuwtfjVff3w68lODFbhwqfA0gf3cPtCgVZ6xQ8P/McNY6K6
 wqFHXMWTDHk1LOCTucjYz1z2TGzTnSG4iWi5Yt6FSxAc958AO+v5ALn/1pcYun+E
 azM/MF0AInKj2aJCT530zT0tpCs/Jo07YKC8k6ubi77S0ZdmGS1XLeXkRXfk1+yI
 OhuUgiVlSTHxD69DagT2vbnx1mDMM9X+OBIMvEi5nwvD9A/ghaCgkDeGFvbA1ud0
 t0mxPBZJ+tiZ
 =JJjG
 -----END PGP SIGNATURE-----

Merge tag 'pull-misc-2022-12-14' of https://repo.or.cz/qemu/armbru into staging

Miscellaneous patches for 2022-12-14

# gpg: Signature made Wed 14 Dec 2022 15:23:02 GMT
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* tag 'pull-misc-2022-12-14' of https://repo.or.cz/qemu/armbru:
  ppc4xx_sdram: Simplify sdram_ddr_size() to return
  block/vmdk: Simplify vmdk_co_create() to return directly
  cleanup: Tweak and re-run return_directly.cocci
  io: Tidy up fat-fingered parameter name
  qapi: Use returned bool to check for failure (again)
  sockets: Use ERRP_GUARD() where obviously appropriate
  qemu-config: Use ERRP_GUARD() where obviously appropriate
  qemu-config: Make config_parse_qdict() return bool
  monitor: Use ERRP_GUARD() in monitor_init()
  monitor: Simplify monitor_fd_param()'s error handling
  error: Move ERRP_GUARD() to the beginning of the function
  error: Drop a few superfluous ERRP_GUARD()
  error: Drop some obviously superfluous error_propagate()
  Drop more useless casts from void * to pointer

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-12-15 10:13:46 +00:00
Markus Armbruster 047f2ca1ce qapi qdev qom: Elide redundant has_FOO in generated C
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with.  Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step.  This is the step for qapi/qdev.json and
qapi/qom.json.

Said commit explains the transformation in more detail.  The invariant
violations mentioned there do not occur here.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: Eduardo Habkost <eduardo@habkost.net>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221104160712.3005652-21-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2022-12-14 20:05:07 +01:00
Markus Armbruster 740d6c4eba error: Drop a few superfluous ERRP_GUARD()
include/qapi/error.h on ERRP_GUARD():

 * It must be used when the function dereferences @errp or passes
 * @errp to error_prepend(), error_vprepend(), or error_append_hint().
 * It is safe to use even when it's not needed, but please avoid
 * cluttering the source with useless code.

Clean up some of this clutter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221121085054.683122-3-armbru@redhat.com>
2022-12-14 16:19:35 +01:00
Claudio Fontana c551fb0b53 module: add Error arguments to module_load and module_load_qom
improve error handling during module load, by changing:

bool module_load(const char *prefix, const char *lib_name);
void module_load_qom(const char *type);

to:

int module_load(const char *prefix, const char *name, Error **errp);
int module_load_qom(const char *type, Error **errp);

where the return value is:

 -1 on module load error, and errp is set with the error
  0 on module or one of its dependencies are not installed
  1 on module load success
  2 on module load success (module already loaded or built-in)

module_load_qom_one has been introduced in:

commit 28457744c3 ("module: qom module support"), which built on top of
module_load_one, but discarded the bool return value. Restore it.

Adapt all callers to emit errors, or ignore them, or fail hard,
as appropriate in each context.

Replace the previous emission of errors via fprintf in _some_ error
conditions with Error and error_report, so as to emit to the appropriate
target.

A memory leak is also fixed as part of the module_load changes.

audio: when attempting to load an audio module, report module load errors.
Note that still for some callers, a single issue may generate multiple
error reports, and this could be improved further.
Regarding the audio code itself, audio_add() seems to ignore errors,
and this should probably be improved.

block: when attempting to load a block module, report module load errors.
For the code paths that already use the Error API, take advantage of those
to report module load errors into the Error parameter.
For the other code paths, we currently emit the error, but this could be
improved further by adding Error parameters to all possible code paths.

console: when attempting to load a display module, report module load errors.

qdev: when creating a new qdev Device object (DeviceState), report load errors.
      If a module cannot be loaded to create that device, now abort execution
      (if no CONFIG_MODULE) or exit (if CONFIG_MODULE).

qom/object.c: when initializing a QOM object, or looking up class_by_name,
              report module load errors.

qtest: when processing the "module_load" qtest command, report errors
       in the load of the module.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929093035.4231-4-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-06 09:48:50 +01:00
Claudio Fontana dbc0e80553 module: rename module_load_one to module_load
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929093035.4231-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-06 09:48:50 +01:00
Jagannathan Raman 217c7f01ad qdev: unplug blocker for devices
Add blocker to prevent hot-unplug of devices

TYPE_VFIO_USER_SERVER, which is introduced shortly, attaches itself to a
PCIDevice on which it depends. If the attached PCIDevice gets removed
while the server in use, it could cause it crash. To prevent this,
TYPE_VFIO_USER_SERVER adds an unplug blocker for the PCIDevice.

Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: c41ef80b7cc063314d629737bed2159e5713f2e0.1655151679.git.jag.raman@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-06-15 14:50:41 +01:00
Philippe Mathieu-Daudé 81c7b38155 hw/core: Extract hotplug-related functions to qdev-hotplug.c
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Yanan Wang <wangyanan55@huawei.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20211028150521.1973821-4-philmd@redhat.com>
2021-11-01 19:44:11 +01:00
Eduardo Habkost b19a3e2cd9 machine: Move gpio code to hw/core/gpio.c
Only softmmu code uses gpio, so move gpio code from qdev.c to
gpio.c and compile it only on softmmu mode.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190425200051.19906-2-ehabkost@redhat.com>
[PMD: Rebased]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-11-01 19:44:00 +01:00
Kevin Wolf f3558b1b76 qdev: Base object creation on QDict rather than QemuOpts
QDicts are both what QMP natively uses and what the keyval parser
produces. Going through QemuOpts isn't useful for either one, so switch
the main device creation function to QDicts. By sharing more code with
the -object/object-add code path, we can even reduce the code size a
bit.

This commit doesn't remove the detour through QemuOpts from any code
path yet, but it allows the following commits to do so.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20211008133442.141332-15-kwolf@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-10-15 16:11:22 +02:00
Kevin Wolf 7d61808206 qdev: Add Error parameter to hide_device() callbacks
hide_device() is used for virtio-net failover, where the standby virtio
device delays creation of the primary device. It only makes sense to
have a single primary device for each standby device. Adding a second
one should result in an error instead of hiding it and never using it
afterwards.

Prepare for this by adding an Error parameter to the hide_device()
callback where virtio-net is informed about adding a primary device.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20211008133442.141332-12-kwolf@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-10-15 16:11:22 +02:00
Kevin Wolf 163f384752 qdev: Make DeviceState.id independent of QemuOpts
DeviceState.id is a pointer to a string that is stored in the QemuOpts
object DeviceState.opts and freed together with it. We want to create
devices without going through QemuOpts in the future, so make this a
separately allocated string.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20211008133442.141332-9-kwolf@redhat.com>
Reviewed-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-10-15 16:06:35 +02:00
Paolo Bonzini 2f181fbd5a machine: introduce MachineInitPhase
Generalize the qdev_hotplug variable to the different phases of
machine initialization.  We would like to allow different
monitor commands depending on the phase.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:51:52 -05:00
Paolo Bonzini f66dc8737c vl: move all generic initialization out of vl.c
qdev_machine_creation_done is only setting a flag now.  Extend it to
move more code out of vl.c.  Leave only consistency checks and gdbserver
processing in qemu_machine_creation_done.

gdbserver_start can be moved after qdev_machine_creation_done because
it only does listen on the socket and creates some internal data
structures; it does not send any data (e.g. guest state) over the socket.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:51:50 -05:00
Eduardo Habkost d3fd6e7380 qdev: Move property code to qdev-properties.[ch]
Move everything related to Property and PropertyInfo to
qdev-properties.[ch] to make it easier to refactor that code.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20201211220529.2290218-4-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-12-15 10:02:07 -05:00
Juan Quintela b91ad981b8 failover: Rename function to hide_device()
You should not use pasive.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20201118083748.1328-17-quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-08 13:48:57 -05:00
Juan Quintela 89631fed27 failover: should_be_hidden() should take a bool
We didn't use at all the -1 value, and we don't really care.  It was
only used for the cases when this is not the device that we are
searching for.  And in that case we should not hide the device.

Once there, simplify virtio-Snet_primary_should_be_hidden.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20201118083748.1328-16-quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-08 13:48:57 -05:00
Chetan Pant 61f3c91a67 nomaintainer: Fix Lesser GPL version number
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.

This patch contains all the files, whose maintainer I could not get
from ‘get_maintainer.pl’ script.

Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023124424.20177-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Adapted exec.c and qdev-monitor.c to new location]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-11-15 17:04:40 +01:00
Maxim Levitsky a23151e8cc device-core: use atomic_set on .realized property
Some code might race with placement of new devices on a bus.
We currently first place a (unrealized) device on the bus
and then realize it.

As a workaround, users that scan the child device list, can
check the realized property to see if it is safe to access such a device.
Use an atomic write here too to aid with this.

A separate discussion is what to do with devices that are unrealized:
It looks like for this case we only call the hotplug handler's unplug
callback and its up to it to unrealize the device.
An atomic operation doesn't cause harm for this code path though.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200913160259.32145-6-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201006123904.610658-10-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-12 11:50:51 -04:00
Maxim Levitsky 2d24a64661 device-core: use RCU for list of children of a bus
This fixes the race between device emulation code that tries to find
a child device to dispatch the request to (e.g a scsi disk),
and hotplug of a new device to that bus.

Note that this doesn't convert all the readers of the list
but only these that might go over that list without BQL held.

This is a very small first step to make this code thread safe.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200913160259.32145-5-mlevitsk@redhat.com>
[Use RCU_READ_LOCK_GUARD in more places, adjust testcase now that
 the delay in DEVICE_DELETED due to RCU is more consistent. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201006123904.610658-9-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-12 11:50:50 -04:00
Paolo Bonzini bb755ba47f qdev: add "check if address free" callback for buses
Check if an address is free on the bus before plugging in the
device.  This makes it possible to do the check without any
side effects, and to detect the problem early without having
to do it in the realize callback.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201006123904.610658-5-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-10-12 11:50:50 -04:00
Peter Maydell b51238e251 qdev: Move doc comments from qdev.c to qdev-core.h
The doc-comments which document the qdev API are split between the
header file and the C source files, because as a project we haven't
been consistent about where we put them.

Move all the doc-comments in qdev.c to the header files, so that
users of the APIs don't have to look at the implementation files for
this information.

In the process, unify them into our doc-comment format and expand on
them in some cases to clarify expected use cases.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200711142425.16283-2-peter.maydell@linaro.org
2020-07-20 11:35:17 +01:00
Markus Armbruster a5f9b9df25 error: Reduce unnecessary error propagation
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, even when we need to keep error_propagate() for other
error paths.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-38-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster f07ad48d46 qom: Use returned bool to check for failure, manual part
The previous commit used Coccinelle to convert from checking the Error
object to checking the return value.  Convert a few more 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: <20200707160613.848843-30-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 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
Gerd Hoffmann 7ab6e7fcce qdev: device module support
Hook module loading into the places where we
need it when building devices as modules.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20200624131045.14512-4-kraxel@redhat.com
2020-07-07 14:54:29 +02:00
Markus Armbruster c835fac3f0 qdev: qdev_init_nofail() is now unused, drop
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-58-armbru@redhat.com>
2020-06-15 22:06:04 +02:00
Markus Armbruster 510ef98dca qdev: Make qdev_realize() support bus-less devices
So far, qdev_realize() supports only devices that plug into a bus:
argument @bus cannot be null.  Extend it to support bus-less devices,
too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-55-armbru@redhat.com>
2020-06-15 22:06:04 +02:00
Markus Armbruster cfe91404c5 qdev: Drop qdev_realize() support for null bus
The "null @bus means main system bus" convenience feature is no longer
used.  Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-47-armbru@redhat.com>
2020-06-15 22:06:04 +02:00
Markus Armbruster 2194abd623 qdev: qdev_create(), qdev_try_create() are now unused, drop
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-31-armbru@redhat.com>
2020-06-15 22:05:28 +02:00
Markus Armbruster dc3edf8d8a qdev: Convert to qdev_unrealize() manually
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-9-armbru@redhat.com>
2020-06-15 21:36:30 +02:00
Markus Armbruster f1483b466d qdev: Convert to qbus_realize(), qbus_unrealize()
I'm going to convert device realization to qdev_realize() with the
help of Coccinelle.  Convert bus realization to qbus_realize() first,
to get it out of Coccinelle's way.  Readability improves.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-7-armbru@redhat.com>
2020-06-15 21:36:30 +02:00
Markus Armbruster 9940b2cfbc qdev: New qdev_new(), qdev_realize(), etc.
We commonly plug devices into their bus right when we create them,
like this:

    dev = qdev_create(bus, type_name);

Note that @dev is a weak reference.  The reference from @bus to @dev
is the only strong one.

We realize at some later time, either with

    object_property_set_bool(OBJECT(dev), true, "realized", errp);

or its convenience wrapper

    qdev_init_nofail(dev);

If @dev still has no QOM parent then, realizing makes the
/machine/unattached/ orphanage its QOM parent.

Note that the device returned by qdev_create() is plugged into a bus,
but doesn't have a QOM parent, yet.  Until it acquires one,
unrealizing the bus will hang in bus_unparent():

    while ((kid = QTAILQ_FIRST(&bus->children)) != NULL) {
        DeviceState *dev = kid->child;
        object_unparent(OBJECT(dev));
    }

object_unparent() does nothing when its argument has no QOM parent,
and the loop spins forever.

Device state "no QOM parent, but plugged into bus" is dangerous.

Paolo suggested to delay plugging into the bus until realize.  We need
to plug into the parent bus before we call the device's realize
method, in case it uses the parent bus.  So the dangerous state still
exists, but only within realization, where we can manage it safely.

This commit creates infrastructure to do this:

    dev = qdev_new(type_name);
    ...
    qdev_realize_and_unref(dev, bus, errp)

Note that @dev becomes a strong reference here.
qdev_realize_and_unref() drops it.  There is also plain
qdev_realize(), which doesn't drop it.

The remainder of this series will convert all users to this new
interface.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: Alistair Francis <alistair@alistair23.me>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200610053247.1583243-5-armbru@redhat.com>
2020-06-15 21:36:30 +02:00
Markus Armbruster dfe8c79c44 qdev: Assert onboard devices all get realized properly
This would have caught some of the bugs I just fixed.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200609122339.937862-25-armbru@redhat.com>
2020-06-15 21:36:30 +02:00
Markus Armbruster 81cb05732e qdev: Assert devices are plugged into a bus that can take them
This would have caught some of the bugs I just fixed.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20200609122339.937862-23-armbru@redhat.com>
2020-06-15 21:36:30 +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 b69c3c21a5 qdev: Unrealize must not fail
Devices may have component devices and buses.

Device realization may fail.  Realization is recursive: a device's
realize() method realizes its components, and device_set_realized()
realizes its buses (which should in turn realize the devices on that
bus, except bus_set_realized() doesn't implement that, yet).

When realization of a component or bus fails, we need to roll back:
unrealize everything we realized so far.  If any of these unrealizes
failed, the device would be left in an inconsistent state.  Must not
happen.

device_set_realized() lets it happen: it ignores errors in the roll
back code starting at label child_realize_fail.

Since realization is recursive, unrealization must be recursive, too.
But how could a partly failed unrealize be rolled back?  We'd have to
re-realize, which can fail.  This design is fundamentally broken.

device_set_realized() does not roll back at all.  Instead, it keeps
unrealizing, ignoring further errors.

It can screw up even for a device with no buses: if the lone
dc->unrealize() fails, it still unregisters vmstate, and calls
listeners' unrealize() callback.

bus_set_realized() does not roll back either.  Instead, it stops
unrealizing.

Fortunately, no unrealize method can fail, as we'll see below.

To fix the design error, drop parameter @errp from all the unrealize
methods.

Any unrealize method that uses @errp now needs an update.  This leads
us to unrealize() methods that can fail.  Merely passing it to another
unrealize method cannot cause failure, though.  Here are the ones that
do other things with @errp:

* virtio_serial_device_unrealize()

  Fails when qbus_set_hotplug_handler() fails, but still does all the
  other work.  On failure, the device would stay realized with its
  resources completely gone.  Oops.  Can't happen, because
  qbus_set_hotplug_handler() can't actually fail here.  Pass
  &error_abort to qbus_set_hotplug_handler() instead.

* hw/ppc/spapr_drc.c's unrealize()

  Fails when object_property_del() fails, but all the other work is
  already done.  On failure, the device would stay realized with its
  vmstate registration gone.  Oops.  Can't happen, because
  object_property_del() can't actually fail here.  Pass &error_abort
  to object_property_del() instead.

* spapr_phb_unrealize()

  Fails and bails out when remove_drcs() fails, but other work is
  already done.  On failure, the device would stay realized with some
  of its resources gone.  Oops.  remove_drcs() fails only when
  chassis_from_bus()'s object_property_get_uint() fails, and it can't
  here.  Pass &error_abort to remove_drcs() instead.

Therefore, no unrealize method can fail before this patch.

device_set_realized()'s recursive unrealization via bus uses
object_property_set_bool().  Can't drop @errp there, so pass
&error_abort.

We similarly unrealize with object_property_set_bool() elsewhere,
always ignoring errors.  Pass &error_abort instead.

Several unrealize methods no longer handle errors from other unrealize
methods: virtio_9p_device_unrealize(),
virtio_input_device_unrealize(), scsi_qdev_unrealize(), ...
Much of the deleted error handling looks wrong anyway.

One unrealize methods no longer ignore such errors:
usb_ehci_pci_exit().

Several realize methods no longer ignore errors when rolling back:
v9fs_device_realize_common(), pci_qdev_unrealize(),
spapr_phb_realize(), usb_qdev_realize(), vfio_ccw_realize(),
virtio_device_realize().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-17-armbru@redhat.com>
2020-05-15 07:08:14 +02:00
Markus Armbruster 40c2281cc3 Drop more @errp parameters after previous commit
Several functions can't fail anymore: ich9_pm_add_properties(),
device_add_bootindex_property(), ppc_compat_add_property(),
spapr_caps_add_properties(), PropertyInfo.create().  Drop their @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: <20200505152926.18877-16-armbru@redhat.com>
2020-05-15 07:08:14 +02:00