Commit Graph

161 Commits

Author SHA1 Message Date
Jonah Palmer 3857cd5c7f virtio: drop name parameter for virtio_init()
This patch drops the name parameter for the virtio_init function.

The pair between the numeric device ID and the string device ID
(name) of a virtio device already exists, but not in a way that
lets us map between them.

This patch lets us do this and removes the need for the name
parameter in the virtio_init function.

Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1648819405-25696-2-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-16 04:38:40 -04:00
Stefan Hajnoczi 3dc584abee virtio-scsi: move request-related items from .h to .c
There is no longer a need to expose the request and related APIs in
virtio-scsi.h since there are no callers outside virtio-scsi.c.

Note the block comment in VirtIOSCSIReq has been adjusted to meet the
coding style.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20220427143541.119567-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-05-09 10:45:04 +01:00
Stefan Hajnoczi ad482b57ef virtio-scsi: clean up virtio_scsi_handle_cmd_vq()
virtio_scsi_handle_cmd_vq() is only called from hw/scsi/virtio-scsi.c
now and its return value is no longer used. Remove the function
prototype from virtio-scsi.h and drop the return value.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20220427143541.119567-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-05-09 10:45:04 +01:00
Stefan Hajnoczi 73b3b49f18 virtio-scsi: clean up virtio_scsi_handle_ctrl_vq()
virtio_scsi_handle_ctrl_vq() is only called from hw/scsi/virtio-scsi.c
now and its return value is no longer used. Remove the function
prototype from virtio-scsi.h and drop the return value.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20220427143541.119567-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-05-09 10:45:04 +01:00
Stefan Hajnoczi 37ce2de951 virtio-scsi: clean up virtio_scsi_handle_event_vq()
virtio_scsi_handle_event_vq() is only called from hw/scsi/virtio-scsi.c
now and its return value is no longer used. Remove the function
prototype from virtio-scsi.h and drop the return value.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20220427143541.119567-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-05-09 10:45:04 +01:00
Stefan Hajnoczi 2f743ef636 virtio-scsi: fix ctrl and event handler functions in dataplane mode
Commit f34e8d8b8d ("virtio-scsi: prepare
virtio_scsi_handle_cmd for dataplane") prepared the virtio-scsi cmd
virtqueue handler function to be used in both the dataplane and
non-datpalane code paths.

It failed to convert the ctrl and event virtqueue handler functions,
which are not designed to be called from the dataplane code path but
will be since the ioeventfd is set up for those virtqueues when
dataplane starts.

Convert the ctrl and event virtqueue handler functions now so they
operate correctly when called from the dataplane code path. Avoid code
duplication by extracting this code into a helper function.

Fixes: f34e8d8b8d ("virtio-scsi: prepare virtio_scsi_handle_cmd for dataplane")
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20220427143541.119567-2-stefanha@redhat.com
[Fixed s/by used/be used/ typo pointed out by Michael Tokarev
<mjt@tls.msk.ru>.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-05-09 10:44:26 +01:00
Stefan Hajnoczi f34e8d8b8d virtio-scsi: prepare virtio_scsi_handle_cmd for dataplane
Prepare virtio_scsi_handle_cmd() to be used by both dataplane and
non-dataplane by making the condition for starting ioeventfd more
specific. This way it won't trigger when dataplane has already been
started.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-01-12 17:09:39 +00:00
Peter Maydell 739e95f574 scsi: Replace scsi_bus_new() with scsi_bus_init(), scsi_bus_init_named()
The function scsi_bus_new() creates a new SCSI bus; callers can
either pass in a name argument to specify the name of the new bus, or
they can pass in NULL to allow the bus to be given an automatically
generated unique name.  Almost all callers want to use the
autogenerated name; the only exception is the virtio-scsi device.

Taking a name argument that should almost always be NULL is an
easy-to-misuse API design -- it encourages callers to think perhaps
they should pass in some standard name like "scsi" or "scsi-bus".  We
don't do this anywhere for SCSI, but we do (incorrectly) do it for
other bus types such as i2c.

The function name also implies that it will return a newly allocated
object, when it in fact does in-place allocation.  We more commonly
name such functions foo_init(), with foo_new() being the
allocate-and-return variant.

Replace all the scsi_bus_new() callsites with either:
 * scsi_bus_init() for the usual case where the caller wants
   an autogenerated bus name
 * scsi_bus_init_named() for the rare case where the caller
   needs to specify the bus name

and document that for the _named() version it's then the caller's
responsibility to think about uniqueness of bus names.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20210923121153.23754-2-peter.maydell@linaro.org
2021-09-30 13:42:10 +01:00
Hannes Reinecke f3126d65b3 scsi: move host_status handling into SCSI drivers
Some SCSI drivers like virtio have an internal mapping for the
host_status. This patch moves the host_status translation into
the SCSI drivers to allow those drivers to set up the correct
values.

Signed-off-by: Hannes Reinecke <hare@suse.de>.
[Added default handling to avoid touching all drivers. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-03-06 11:42:57 +01:00
Hannes Reinecke 17ea26c2d8 scsi: drop 'result' argument from command_complete callback
The command complete callback has a SCSIRequest as the first argument,
and the status field of that structure is identical to the 'status'
argument. So drop the argument from the callback.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20201116184041.60465-3-hare@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-02-25 14:14:32 +01:00
Sergio Lopez c7040ff64e block: Honor blk_set_aio_context() context requirements
The documentation for bdrv_set_aio_context_ignore() states this:

 * The caller must own the AioContext lock for the old AioContext of bs, but it
 * must not own the AioContext lock for new_context (unless new_context is the
 * same as the current context of bs).

As blk_set_aio_context() makes use of this function, this rule also
applies to it.

Fix all occurrences where this rule wasn't honored.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Sergio Lopez <slp@redhat.com>
Message-Id: <20201214170519.223781-2-slp@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-01-20 14:48:08 -06:00
Hannes Reinecke eb8cb3d9dc virtio-scsi: trace events
Add trace events for virtio command and response tracing.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Message-Id: <20201116183114.55703-2-hare@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-01-12 12:38:03 +01:00
Maxim Levitsky 07a47d4a18 virtio-scsi: use scsi_device_get
This will help us to avoid the scsi device disappearing
after we took a reference to it.

It doesn't by itself forbid case when we try to access
an unrealized device

Suggested-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200913160259.32145-9-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201006123904.610658-13-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
Stefan Hajnoczi 6a55882284 virtio-scsi-pci: default num_queues to -smp N
Automatically size the number of virtio-scsi-pci, vhost-scsi-pci, and
vhost-user-scsi-pci request virtqueues to match the number of vCPUs.
Other transports continue to default to 1 request virtqueue.

A 1:1 virtqueue:vCPU mapping ensures that completion interrupts are
handled on the same vCPU that submitted the request.  No IPI is
necessary to complete an I/O request and performance is improved.  The
maximum number of MSI-X vectors and virtqueues limit are respected.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200818143348.310613-6-stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-27 08:29:13 -04:00
Stefan Hajnoczi 4e5163bd84 virtio-scsi: introduce a constant for fixed virtqueues
The event and control virtqueues are always present, regardless of the
multi-queue configuration.  Define a constant so that virtqueue number
calculations are easier to read.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20200818143348.310613-5-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-27 08:29:13 -04:00
Markus Armbruster 9bc6bfdf67 qdev: Drop qbus_set_hotplug_handler() parameter @errp
qbus_set_hotplug_handler() is a simple wrapper around
object_property_set_link().

object_property_set_link() fails when the property doesn't exist, is
not settable, or its .check() method fails.  These are all programming
errors here, so passing &error_abort to qbus_set_hotplug_handler() is
appropriate.

Most of its callers do.  Exceptions:

* pcie_cap_slot_init(), shpc_init(), spapr_phb_realize() pass NULL,
  i.e. they ignore errors.

* spapr_machine_init() passes &error_fatal.

* s390_pcihost_realize(), virtio_serial_device_realize(),
  s390_pcihost_plug() pass the error to their callers.  The latter two
  keep going after the error, which looks wrong.

Drop the @errp parameter, and instead pass &error_abort to
object_property_set_link().

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200630090351.1247703-15-armbru@redhat.com>
2020-07-02 06:25:29 +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
Denis Plotnikov c9b7d9ec21 virtio: increase virtqueue size for virtio-scsi and virtio-blk
The goal is to reduce the amount of requests issued by a guest on
1M reads/writes. This rises the performance up to 4% on that kind of
disk access pattern.

The maximum chunk size to be used for the guest disk accessing is
limited with seg_max parameter, which represents the max amount of
pices in the scatter-geather list in one guest disk request.

Since seg_max is virqueue_size dependent, increasing the virtqueue
size increases seg_max, which, in turn, increases the maximum size
of data to be read/write from a guest disk.

More details in the original problem statment:
https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html

Suggested-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-02-22 08:26:47 +00:00
Marc-André Lureau 4f67d30b5e qdev: set properties with device_class_set_props()
The following patch will need to handle properties registration during
class_init time. Let's use a device_class_set_props() setter.

spatch --macro-file scripts/cocci-macro-file.h  --sp-file
./scripts/coccinelle/qdev-set-props.cocci --keep-comments --in-place
--dir .

@@
typedef DeviceClass;
DeviceClass *d;
expression val;
@@
- d->props = val
+ device_class_set_props(d, val)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-20-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:15 +01:00
Pan Nengyuan 36fc9bd386 virtio-scsi: convert to new virtio_delete_queue
Use virtio_delete_queue to make it more clear.

Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200117075547.60864-3-pannengyuan@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:10 +01:00
Pan Nengyuan c9c0ed6976 virtio-scsi: delete vqs in unrealize to avoid memleaks
This patch fix memleaks when attaching/detaching virtio-scsi device, the
memory leak stack is as follow:

Direct leak of 21504 byte(s) in 3 object(s) allocated from:
  #0 0x7f491f2f2970 (/lib64/libasan.so.5+0xef970)  ??:?
  #1 0x7f491e94649d (/lib64/libglib-2.0.so.0+0x5249d)  ??:?
  #2 0x564d0f3919fa (./x86_64-softmmu/qemu-system-x86_64+0x2c3e9fa)  /mnt/sdb/qemu/hw/virtio/virtio.c:2333
  #3 0x564d0f2eca55 (./x86_64-softmmu/qemu-system-x86_64+0x2b99a55)  /mnt/sdb/qemu/hw/scsi/virtio-scsi.c:912
  #4 0x564d0f2ece7b (./x86_64-softmmu/qemu-system-x86_64+0x2b99e7b)  /mnt/sdb/qemu/hw/scsi/virtio-scsi.c:924
  #5 0x564d0f39ee47 (./x86_64-softmmu/qemu-system-x86_64+0x2c4be47)  /mnt/sdb/qemu/hw/virtio/virtio.c:3531
  #6 0x564d0f980224 (./x86_64-softmmu/qemu-system-x86_64+0x322d224)  /mnt/sdb/qemu/hw/core/qdev.c:865

Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200117075547.60864-2-pannengyuan@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-24 20:59:10 +01:00
Denis Plotnikov 1bf8a989a5 virtio: make seg_max virtqueue size dependent
Before the patch, seg_max parameter was immutable and hardcoded
to 126 (128 - 2) without respect to queue size. This has two negative effects:

1. when queue size is < 128, we have Virtio 1.1 specfication violation:
   (2.6.5.3.1 Driver Requirements) seq_max must be <= queue_size.
   This violation affects the old Linux guests (ver < 4.14). These guests
   crash on these queue_size setups.

2. when queue_size > 128, as was pointed out by Denis Lunev <den@virtuozzo.com>,
   seg_max restrics guest's block request length which affects guests'
   performance making them issues more block request than needed.
   https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html

To mitigate this two effects, the patch adds the property adjusting seg_max
to queue size automaticaly. Since seg_max is a guest visible parameter,
the property is machine type managable and allows to choose between
old (seg_max = 126 always) and new (seg_max = queue_size - 2) behaviors.

Not to change the behavior of the older VMs, prevent setting the default
seg_max_adjust value for older machine types.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com>
Message-Id: <20191220140905.1718-2-dplotnikov@virtuozzo.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-01-06 12:04:43 -05:00
Stefan Hajnoczi d0435bc513 virtio: don't enable notifications during polling
Virtqueue notifications are not necessary during polling, so we disable
them.  This allows the guest driver to avoid MMIO vmexits.
Unfortunately the virtio-blk and virtio-scsi handler functions re-enable
notifications, defeating this optimization.

Fix virtio-blk and virtio-scsi emulation so they leave notifications
disabled.  The key thing to remember for correctness is that polling
always checks one last time after ending its loop, therefore it's safe
to lose the race when re-enabling notifications at the end of polling.

There is a measurable performance improvement of 5-10% with the null-co
block driver.  Real-life storage configurations will see a smaller
improvement because the MMIO vmexit overhead contributes less to
latency.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191209210957.65087-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-01-05 07:03:03 -05:00
Jason Wang 86044b24e8 virtio: basic packed virtqueue support
This patch implements basic support for the packed virtqueue. Compare
the split virtqueue which has three rings, packed virtqueue only have
one which is supposed to have better cache utilization and more
hardware friendly.

Please refer virtio specification for more information.

Signed-off-by: Wei Xu <wexu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20191025083527.30803-6-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-25 07:46:22 -04:00
Markus Armbruster a27bd6c779 Include hw/qdev-properties.h less
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h.  Include hw/qdev-core.h there
instead.

hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.

While there, delete a few superfluous inclusions of hw/qdev-core.h.

Touching hw/qdev-properties.h now recompiles some 1200 objects.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
2019-08-16 13:31:53 +02:00
Markus Armbruster ca77ee28e0 Include migration/qemu-file-types.h a lot less
In my "build everything" tree, changing migration/qemu-file-types.h
triggers a recompile of some 2600 out of 6600 objects (not counting
tests and objects that don't depend on qemu/osdep.h).

The culprit is again hw/hw.h, which supposedly includes it for
convenience.

Include migration/qemu-file-types.h only where it's needed.  Touching
it now recompiles less than 200 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Zhengui li 9c5aad84da virtio-scsi: fixed virtio_scsi_ctx_check failed when detaching scsi disk
commit a6f230c move blockbackend back to main AioContext on unplug. It set the AioContext of
SCSIDevice to the main AioContex, but s->ctx is still the iothread AioContex(if the scsi controller
is configure with iothread). So if there are having in-flight requests during unplug, a failing assertion
happend. The bt is below:
(gdb) bt
#0  0x0000ffff86aacbd0 in raise () from /lib64/libc.so.6
#1  0x0000ffff86aadf7c in abort () from /lib64/libc.so.6
#2  0x0000ffff86aa6124 in __assert_fail_base () from /lib64/libc.so.6
#3  0x0000ffff86aa61a4 in __assert_fail () from /lib64/libc.so.6
#4  0x0000000000529118 in virtio_scsi_ctx_check (d=<optimized out>, s=<optimized out>, s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:246
#5  0x0000000000529ec4 in virtio_scsi_handle_cmd_req_prepare (s=0x2779ec00, req=0xffff740397d0) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:559
#6  0x000000000052a228 in virtio_scsi_handle_cmd_vq (s=0x2779ec00, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:603
#7  0x000000000052afa8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>, vq=0xffff7c6d7110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:59
#8  0x000000000054d94c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>) at /home/qemu-4.0.0/hw/virtio/virtio.c:2452

assert(blk_get_aio_context(d->conf.blk) == s->ctx) failed.

To avoid assertion failed,  moving the "if" after qdev_simple_device_unplug_cb.

In addition, to avoid another qemu crash below, add aio_disable_external before
qdev_simple_device_unplug_cb, which disable the further processing of external clients
when doing qdev_simple_device_unplug_cb.
(gdb) bt
#0  scsi_req_unref (req=0xffff6802c6f0) at hw/scsi/scsi-bus.c:1283
#1  0x00000000005294a4 in virtio_scsi_handle_cmd_req_submit (req=<optimized out>,
    s=<optimized out>) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:589
#2  0x000000000052a2a8 in virtio_scsi_handle_cmd_vq (s=s@entry=0x9c90e90,
    vq=vq@entry=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi.c:625
#3  0x000000000052afd8 in virtio_scsi_data_plane_handle_cmd (vdev=<optimized out>,
    vq=0xffff7c05f110) at /home/qemu-4.0.0/hw/scsi/virtio-scsi-dataplane.c:60
#4  0x000000000054d97c in virtio_queue_host_notifier_aio_poll (opaque=<optimized out>)
    at /home/qemu-4.0.0/hw/virtio/virtio.c:2447
#5  0x00000000009b204c in run_poll_handlers_once (ctx=ctx@entry=0x6efea40,
    timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:521
#6  0x00000000009b2b64 in run_poll_handlers (ctx=ctx@entry=0x6efea40,
    max_ns=max_ns@entry=4000, timeout=timeout@entry=0xffff7d7f7308) at util/aio-posix.c:559
#7  0x00000000009b2ca0 in try_poll_mode (ctx=ctx@entry=0x6efea40, timeout=0xffff7d7f7308,
    timeout@entry=0xffff7d7f7348) at util/aio-posix.c:594
#8  0x00000000009b31b8 in aio_poll (ctx=0x6efea40, blocking=blocking@entry=true)
    at util/aio-posix.c:636
#9  0x00000000006973cc in iothread_run (opaque=0x6ebd800) at iothread.c:75
#10 0x00000000009b592c in qemu_thread_start (args=0x6efef60) at util/qemu-thread-posix.c:502
#11 0x0000ffff8057f8bc in start_thread () from /lib64/libpthread.so.0
#12 0x0000ffff804e5f8c in thread_start () from /lib64/libc.so.6
(gdb) p bus
$1 = (SCSIBus *) 0x0

Signed-off-by: Zhengui li <lizhengui@huawei.com>
Message-Id: <1563696502-7972-1-git-send-email-lizhengui@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1563829520-17525-1-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-24 11:21:53 +02:00
Paolo Bonzini 12e1dc4939 virtio-scsi: remove unused argument to virtio_scsi_common_realize
The argument is not used and passing it clutters error propagation in the
callers.  So, get rid of it.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-19 19:04:38 +02:00
Markus Armbruster 0b8fa32f55 Include qemu/module.h where needed, drop it from qemu-common.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-4-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c
hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c;
ui/cocoa.m fixed up]
2019-06-12 13:18:33 +02:00
Philippe Mathieu-Daudé 824755baf8 hw/scsi: Use the QOM BUS() macro to access BusState.qbus
Rather than looking inside the definition of a BusState with "s->bus.qbus",
use the QOM prefered style: "BUS(&s->bus)".

This patch was generated using the following Coccinelle script:

    // Use BUS() macros to access BusState.qbus
    @use_bus_macro_to_access_qbus@
    expression obj;
    identifier bus;
    @@
    -&obj->bus.qbus
    +BUS(&obj->bus)

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190528164020.32250-3-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-06-06 11:54:07 +02:00
Kevin Wolf 4f71fb436a scsi-disk: Use qdev_prop_drive_iothread
This makes use of qdev_prop_drive_iothread for scsi-disk so that the
disk can be attached to a node that is already in the target AioContext.
We need to check that the HBA actually supports iothreads, otherwise
scsi-disk must make sure that the node is already in the main
AioContext.

This changes the error message for conflicting iothread settings.
Previously, virtio-scsi produced the error message, now it comes from
blk_set_aio_context(). Update a test case accordingly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04 15:22:22 +02:00
Kevin Wolf 97896a4887 block: Add Error to blk_set_aio_context()
Add an Error parameter to blk_set_aio_context() and use
bdrv_child_try_set_aio_context() internally to check whether all
involved nodes can actually support the AioContext switch.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04 15:22:22 +02:00
Greg Kurz d804232dc4 virtio-scsi: Fix build with gcc 9
Build fails with gcc 9:

  CC      ppc64-softmmu/hw/scsi/virtio-scsi.o
hw/scsi/virtio-scsi.c: In function ‘virtio_scsi_do_tmf’:
hw/scsi/virtio-scsi.c:265:39: error: taking address of packed member of ‘struct virtio_scsi_ctrl_tmf_req’ may result in an unaligned pointer value [-Werror=address-of-packed-member]
  265 |     virtio_tswap32s(VIRTIO_DEVICE(s), &req->req.tmf.subtype);
      |                                       ^~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors

All the fields in struct virtio_scsi_ctrl_tmf_req are naturally aligned,
so we could in theory drop QEMU_PACKED. Unfortunately, the header file
is imported from linux which already has the packed attribute. Trying to
fix that in the update-linux-headers.sh script is likely to produce
ugliness. Turn the call to virtio_tswap32s() into an assignment instead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155137678223.44753.5438092367451176318.stgit@bahia.lan>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-11 16:33:49 +01:00
Michael Roth 94d1cc5f03 qdev: pass an Object * to qbus_set_hotplug_handler()
Certain devices types, like memory/CPU, are now being handled using a
hotplug interface provided by a top-level MachineClass. Hotpluggable
host bridges are another such device where it makes sense to use a
machine-level hotplug handler. However, unlike those devices,
host-bridges have a parent bus (the main system bus), and devices with
a parent bus use a different mechanism for registering their hotplug
handlers: qbus_set_hotplug_handler(). This interface currently expects
a handler to be a subclass of DeviceClass, but this is not the case
for MachineClass, which derives directly from ObjectClass.

Internally, the interface only requires an ObjectClass, so expose that
in qbus_set_hotplug_handler().

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <154999589921.690774.3640149277362188566.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-02-17 21:54:02 +11:00
Alberto Garcia eb97813ff5 virtio-scsi: Forbid devices with different iothreads sharing a blockdev
This patch forbids attaching a disk to a SCSI device if its using a
different AioContext. Test case included.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-02-01 13:46:45 +01:00
Alberto Garcia a6f230c8d1 virtio-scsi: Move BlockBackend back to the main AioContext on unplug
This fixes a crash when attaching a disk to a SCSI device using
iothreads, then detaching it and reattaching it again. Test case
included.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-02-01 13:46:45 +01:00
Igor Mammedov 8b5e6caf01 call HotplugHandler->plug() as the last step in device realization
When [2] was fixed it was agreed that adding and calling post_plug()
callback after device_reset() was low risk approach to hotfix issue
right before release. So it was merged instead of moving already
existing plug() callback after device_reset() is called which would
be more risky and require all plug() callbacks audit.

Looking at the current plug() callbacks, it doesn't seem that moving
plug() callback after device_reset() is breaking anything, so here
goes agreed upon [3] proper fix which essentially reverts [1][2]
and moves plug() callback after device_reset().
This way devices always comes to plug() stage, after it's been fully
initialized (including being reset), which fixes race condition [2]
without need for an extra post_plug() callback.

 1. (25e897881 "qdev: add HotplugHandler->post_plug() callback")
 2. (8449bcf94 "virtio-scsi: fix hotplug ->reset() vs event race")
 3. https://www.mail-archive.com/qemu-devel@nongnu.org/msg549915.html

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1539696820-273275-1-git-send-email-imammedo@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Pierre Morel<pmorel@linux.ibm.com>
Acked-by: Pierre Morel<pmorel@linux.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-19 13:44:12 +02:00
Stefan Hajnoczi 8449bcf949 virtio-scsi: fix hotplug ->reset() vs event race
There is a race condition during hotplug when iothread is used.  It
occurs because virtio-scsi may be processing command queues in the
iothread while the monitor performs SCSI device hotplug.

When a SCSI device is hotplugged the HotplugHandler->plug() callback is
invoked and virtio-scsi emits a rescan event to the guest.

If the guest submits a SCSI command at this point then it may be
cancelled before hotplug completes.  This happens because ->reset() is
called by hw/core/qdev.c:device_set_realized() after
HotplugHandler->plug() has been called and
hw/scsi/scsi-disk.c:scsi_disk_reset() purges all requests.

This patch uses the new HotplugHandler->post_plug() callback to emit the
rescan event after ->reset().  This eliminates the race conditions where
requests could be cancelled.

Reported-by: l00284672 <lizhengui@huawei.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20180716083732.3347-3-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-07-16 16:58:16 +02:00
Paolo Bonzini 08e2c9f19c scsi: move block/scsi.h to include/scsi/constants.h
Complete the transition by renaming this header, which was
shared by block/iscsi.c and the SCSI emulation code.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-19 14:09:31 +02:00
Richard W.M. Jones 5c0919d020 virtio-scsi: Add virtqueue_size parameter allowing virtqueue size to be set.
Since Linux switched to blk-mq as the default in Linux commit
5c279bd9e406 ("scsi: default to scsi-mq"), virtio-scsi LUNs consume
about 10x as much guest kernel memory.

This commit allows you to choose the virtqueue size for each
virtio-scsi-pci controller like this:

  -device virtio-scsi-pci,id=scsi,virtqueue_size=16

The default is still 128 as before.  Using smaller virtqueue_size
allows many more disks to be added to small memory virtual machines.
For a 1 vCPU, 500 MB, no swap VM I observed:

  With scsi-mq enabled (upstream kernel):              175 disks
    -"- ditto -"-   virtqueue_size=64:                 318 disks
    -"- ditto -"-   virtqueue_size=16:                 775 disks
  With scsi-mq disabled (kernel before 5c279bd9e406): 1755 disks

Note that to have any effect, this requires a kernel patch:

  https://lkml.org/lkml/2017/8/10/689

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Message-Id: <20170810165255.20865-1-rjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-19 14:09:11 +02:00
Fam Zheng 08f1ecd873 virtio-scsi: Convert to DEFINE_PROP_LINK
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170714021509.23681-8-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 12:04:42 +02:00
Jason Wang 025bdeab3c virtio-scsi: finalize IOMMU support
After converting to use DMA api for virtio devices, we should use
dma_as instead of address_space_memory. Otherwise it won't work if
IOMMU is enabled.

Fixes: commit 8607f5c307 ("virtio: convert to use DMA api")
Cc: qemu-stable@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <1499170866-9068-1-git-send-email-jasowang@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-04 14:39:28 +02:00
Fam Zheng 2cbe2de545 virtio-scsi: Unset hotplug handler when unrealize
This matches the qbus_set_hotplug_handler in realize, and it releases
the final reference to the embedded VirtIODevice so that it is
properly finalized.

A use-after-free is fixed with this patch, indirectly:
virtio_device_instance_finalize wasn't called at hot-unplug, and the
vdev->listener would be a dangling pointer in the global and the per
address space listener list. See also RHBZ 1449031.

Cc: qemu-stable@nongnu.org
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170518102808.30046-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-06 20:18:36 +02:00
Fam Zheng bf46e67ddb scsi: Make errp the last parameter of virtio_scsi_common_realize
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170421122710.15373-12-famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-04-24 09:13:44 +02:00
Fam Zheng 7140778605 virtio-scsi: Fix acquire/release in dataplane handlers
After the AioContext lock push down, there is a race between
virtio_scsi_dataplane_start and those "assert(s->ctx &&
s->dataplane_started)", because the latter doesn't isn't wrapped in
aio_context_acquire.

Reproducer is simply booting a Fedora guest with an empty
virtio-scsi-dataplane controller:

    qemu-system-x86_64 \
      -drive if=none,id=root,format=raw,file=Fedora-Cloud-Base-25-1.3.x86_64.raw \
      -device virtio-scsi \
      -device scsi-disk,drive=root,bootindex=1 \
      -object iothread,id=io \
      -device virtio-scsi-pci,iothread=io \
      -net user,hostfwd=tcp::10022-:22 -net nic,model=virtio -m 2048 \
      --enable-kvm

Fix this by moving acquire/release pairs from virtio_scsi_handle_*_vq to
their callers - and wrap the broken assertions in.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170317061447.16243-3-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-24 11:49:03 +01:00
Fam Zheng 3d69f82161 virtio-scsi: Make virtio_scsi_acquire/release public
They will be used in virtio-scsi-dataplane.c as well, so move them to
header.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170317061447.16243-2-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-24 11:48:58 +01:00
Peter Maydell a1cf5fac2b Changes to -drive without if= and with if=scsi
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Merge remote-tracking branch 'remotes/armbru/tags/pull-block-2017-02-21' into staging

Changes to -drive without if= and with if=scsi

# gpg: Signature made Tue 21 Feb 2017 12:22:35 GMT
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-block-2017-02-21:
  hw/i386: Deprecate -drive if=scsi with PC machine types
  hw: Deprecate -drive if=scsi with non-onboard HBAs
  hw/scsi: Concentrate -drive if=scsi auto-create in one place
  hw: Drop superfluous special checks for orphaned -drive
  blockdev: Make orphaned -drive fatal
  blockdev: Improve message for orphaned -drive
  hw/arm/highbank: Default -drive to if=ide instead of if=scsi
  hw: Default -drive to if=none instead of scsi when scsi cannot work
  hw: Default -drive to if=none instead of ide when ide cannot work
  hw/arm/cubieboard hw/arm/xlnx-ep108: Fix units_per_default_bus
  hw: Default -drive to if=ide explicitly where it works

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-02-21 13:58:50 +00:00
Markus Armbruster fb8b660e17 hw/scsi: Concentrate -drive if=scsi auto-create in one place
The logic to create frontends for -drive if=scsi is in SCSI HBAs.  For
all other interface types, it's in machine initialization code.

A few machine types create the SCSI HBAs necessary for that.  That's
also not done for other interface types.

I'm going to deprecate these SCSI eccentricities.  In preparation for
that, create the frontends in main() instead of the SCSI HBAs, by
calling new function scsi_legacy_handle_cmdline() there.

Note that not all SCSI HBAs create frontends.  Take care not to change
that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1487161136-9018-2-git-send-email-armbru@redhat.com>
Acked-By: Paolo Bonzini <pbonzini@redhat.com>
2017-02-21 13:17:45 +01:00
Paolo Bonzini 9d45665448 block: explicitly acquire aiocontext in callbacks that need it
This covers both file descriptor callbacks and polling callbacks,
since they execute related code.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20170213135235.12274-14-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-21 11:39:36 +00:00