Commit Graph

813 Commits

Author SHA1 Message Date
Pankaj Gupta 207efa18ac virtio pmem: remove transitional names
Remove transitional & non transitional names for virtio pmem.
Only virtio 1.0 and up is supported.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Message-Id: <20190712073554.21918-4-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-07-12 10:57:27 -04:00
Pankaj Gupta 7b8a847424 virtio pmem: remove memdev null check
Coverity reports that when we're assigning vi->size we handle the
"pmem->memdev is NULL" case; but we then pass it into
object_get_canonical_path(), which unconditionally dereferences it
and will crash if it is NULL. If this pointer can be NULL then we
need to do something else here.

We are removing 'pmem->memdev' null check here as memdev will never
be null in this function.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Message-Id: <20190712073554.21918-3-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-07-12 10:56:27 -04:00
Pankaj Gupta f37f471262 virtio pmem: fix wrong mem region condition
Coverity reported memory region returns zero
for non-null value. This is because of wrong
arguments to '?:' , fixing this.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Message-Id: <20190712073554.21918-2-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-07-12 10:56:27 -04:00
Stefan Hajnoczi 2bbadb08ce virtio-balloon: fix QEMU 4.0 config size migration incompatibility
The virtio-balloon config size changed in QEMU 4.0 even for existing
machine types.  Migration from QEMU 3.1 to 4.0 can fail in some
circumstances with the following error:

  qemu-system-x86_64: get_pci_config_device: Bad config data: i=0x10 read: a1 device: 1 cmask: ff wmask: c0 w1cmask:0

This happens because the virtio-balloon config size affects the VIRTIO
Legacy I/O Memory PCI BAR size.

Introduce a qdev property called "qemu-4-0-config-size" and enable it
only for the QEMU 4.0 machine types.  This way <4.0 machine types use
the old size, 4.0 uses the larger size, and >4.0 machine types use the
appropriate size depending on enabled virtio-balloon features.

Live migration to and from old QEMUs to QEMU 4.1 works again as long as
a versioned machine type is specified (do not use just "pc"!).

Originally-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20190710141440.27635-1-stefanha@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-12 10:56:26 -04:00
Stefan Hajnoczi 1a8c091c4e virtio-scsi: restart DMA after iothread
When the 'cont' command resumes guest execution the vm change state
handlers are invoked.  Unfortunately there is no explicit ordering
between classic qemu_add_vm_change_state_handler() callbacks.  When two
layers of code both use vm change state handlers, we don't control which
handler runs first.

virtio-scsi with iothreads hits a deadlock when a failed SCSI command is
restarted and completes before the iothread is re-initialized.

This patch uses the new qdev_add_vm_change_state_handler() API to
guarantee that virtio-scsi's virtio change state handler executes before
the SCSI bus children.  This way DMA is restarted after the iothread has
re-initialized.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-07-08 16:00:26 +02:00
Xie Yongji 4c5cf37b50 virtio: Don't change "started" flag on virtio_vmstate_change()
We will call virtio_set_status() on virtio_vmstate_change().
The "started" flag should not be changed in this case. Otherwise,
we may get an incorrect value when we set "started" flag but
not set DRIVER_OK in source VM.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Message-Id: <20190626023130.31315-6-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji 8b04e2c797 virtio: Make sure we get correct state of device on handle_aio_output()
We should set the flags: "start_on_kick" and "started" after we call
the kick functions (handle_aio_output() and handle_output()).

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Message-Id: <20190626023130.31315-5-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji 868a8f44f5 virtio: Set "start_on_kick" on virtio_set_features()
The guest feature is not set correctly on virtio_reset() and
virtio_init(). So we should not use it to set "start_on_kick" at that
point. This patch set "start_on_kick" on virtio_set_features() instead.

Fixes: badaf79cfd ("virtio: Introduce started flag to VirtioDevice")
Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20190626023130.31315-4-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji 7abccd088c virtio: Set "start_on_kick" for legacy devices
Besides virtio 1.0 transitional devices, we should also
set "start_on_kick" flag for legacy devices (virtio 0.9).

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20190626023130.31315-3-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji e57f2c31b6 virtio: add "use-started" property
In order to avoid migration issues, we introduce a "use-started"
property to the base virtio device to indicate whether use
"started" flag or not. This property will be true by default and
set to false when machine type <= 4.0.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Message-Id: <20190626023130.31315-2-xieyongji@baidu.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Marc-André Lureau 683c1d89ef virtio-pci: fix missing device properties
Since commit a4ee4c8baa ("virtio: Helper for registering virtio
device types"), virtio-gpu-pci, virtio-vga, and virtio-crypto-pci lost
some properties: "ioeventfd" and "vectors". This may cause various
issues, such as failing migration or invalid properties.

Since those VirtioPCI devices do not have a base name, their class are
initialized with virtio_pci_generic_base_class_init(). However, if the
VirtioPCIDeviceTypeInfo provided a class_init which sets dc->props,
the properties were overwritten by virtio_pci_generic_class_init().

Instead, introduce an intermediary base-type to register the generic
properties.

Fixes: a4ee4c8baa
Cc: qemu-stable@nongnu.org
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190625232333.30752-1-marcandre.lureau@redhat.com>
2019-07-04 17:00:32 -04:00
Pankaj Gupta adf0748a49 virtio-pci: Proxy for virtio-pmem
We need a proxy device for virtio-pmem, and this device has to be the
actual memory device so we can cleanly hotplug it.

Forward memory device class functions either to the actual device or use
properties of the virtio-pmem device to implement these in the proxy.

virtio-pmem will only be compiled for selected, supported architectures
(that can deal with virtio/pci devices being memory devices). An
architecture that is prepared for that can simply enable
CONFIG_VIRTIO_PMEM to make it work.

As not all architectures support memory devices (and CONFIG_VIRTIO_PMEM
will be enabled per supported architecture), we have to move the PCI proxy
to a separate file.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
[ split up patches, memory-device changes, move pci proxy]
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190619094907.10131-5-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
David Hildenbrand 1e33b513f2 virtio-pci: Allow to specify additional interfaces for the base type
Let's allow to specify additional interfaces for the base type (e.g.
later TYPE_MEMORY_DEVICE), something that was possible before the
rework of virtio PCI device instantiation.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190619094907.10131-3-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-02 12:59:22 -04:00
Pankaj Gupta 5f503cd9f3 virtio-pmem: add virtio device
This is the implementation of virtio-pmem device. Support will require
machine changes for the architectures that will support it, so it will
not yet be compiled. It can be unlocked with VIRTIO_PMEM_SUPPORTED per
machine and disabled globally via VIRTIO_PMEM.

We cannot use the "addr" property as that is already used e.g. for
virtio-pci/pci devices. And we will have e.g. virtio-pmem-pci as a proxy.
So we have to choose a different one (unfortunately). "memaddr" it is.
That name should ideally be used by all other virtio-* based memory
devices in the future.
    -device virtio-pmem-pci,id=p0,bus=bux0,addr=0x01,memaddr=0x1000000...

Acked-by: Markus Armbruster <armbru@redhat.com>
[ QAPI bits ]
Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
[ MemoryDevice/MemoryRegion changes, cleanups, addr property "memaddr",
  split up patches, unplug handler ]
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190619094907.10131-2-pagupta@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-07-02 12:59:22 -04:00
Li Hangjing 240e647a14 vhost: fix vhost_log size overflow during migration
When a guest which doesn't support multiqueue is migrated with a multi queues
vhost-user-blk deivce, a crash will occur like:

0 qemu_memfd_alloc (name=<value optimized out>, size=562949953421312, seals=<value optimized out>, fd=0x7f87171fe8b4, errp=0x7f87171fe8a8) at util/memfd.c:153
1 0x00007f883559d7cf in vhost_log_alloc (size=70368744177664, share=true) at hw/virtio/vhost.c:186
2 0x00007f88355a0758 in vhost_log_get (listener=0x7f8838bd7940, enable=1) at qemu-2-12/hw/virtio/vhost.c:211
3 vhost_dev_log_resize (listener=0x7f8838bd7940, enable=1) at hw/virtio/vhost.c:263
4 vhost_migration_log (listener=0x7f8838bd7940, enable=1) at hw/virtio/vhost.c:787
5 0x00007f88355463d6 in memory_global_dirty_log_start () at memory.c:2503
6 0x00007f8835550577 in ram_init_bitmaps (f=0x7f88384ce600, opaque=0x7f8836024098) at migration/ram.c:2173
7 ram_init_all (f=0x7f88384ce600, opaque=0x7f8836024098) at migration/ram.c:2192
8 ram_save_setup (f=0x7f88384ce600, opaque=0x7f8836024098) at migration/ram.c:2219
9 0x00007f88357a419d in qemu_savevm_state_setup (f=0x7f88384ce600) at migration/savevm.c:1002
10 0x00007f883579fc3e in migration_thread (opaque=0x7f8837530400) at migration/migration.c:2382
11 0x00007f8832447893 in start_thread () from /lib64/libpthread.so.0
12 0x00007f8832178bfd in clone () from /lib64/libc.so.6

This is because vhost_get_log_size() returns a overflowed vhost-log size.
In this function, it uses the uninitialized variable vqs->used_phys and
vqs->used_size to get the vhost-log size.

Signed-off-by: Li Hangjing <lihangjing@baidu.com>
Reviewed-by: Xie Yongji <xieyongji@baidu.com>
Reviewed-by: Chai Wen <chaiwen@baidu.com>
Message-Id: <20190603061524.24076-1-lihangjing@baidu.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-16 16:16:52 -04:00
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
Peter Maydell 347a6f44e9 virtio, pci, pc: cleanups, features
stricter rules for acpi tables: we now fail
 on any difference that isn't whitelisted.
 
 vhost-scsi migration.
 
 some cleanups all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pci, pc: cleanups, features

stricter rules for acpi tables: we now fail
on any difference that isn't whitelisted.

vhost-scsi migration.

some cleanups all over the place

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 05 Jun 2019 20:55:04 BST
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream:
  bios-tables-test: ignore identical binaries
  tests: acpi: add simple arm/virt testcase
  tests: add expected ACPI tables for arm/virt board
  bios-tables-test: list all tables that differ
  vhost-scsi: Allow user to enable migration
  vhost-scsi: Add VMState descriptor
  vhost-scsi: The vhost backend should be stopped when the VM is not running
  bios-tables-test: add diff allowed list
  vhost: fix memory leak in vhost_user_scsi_realize
  vhost: fix incorrect print type
  vhost: remove the dead code
  docs: smbios: remove family=x from type2 entry description
  pci: Fold pci_get_bus_devfn() into its sole caller
  pci: Make is_bridge a bool
  pcie: Simplify pci_adjust_config_limit()
  acpi: pci: use build_append_foo() API to construct MCFG
  hw/acpi: Consolidate build_mcfg to pci.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-06-06 12:52:31 +01:00
Peter Maydell 95172e2405 vga: add vhost-user-gpu.
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Merge remote-tracking branch 'remotes/kraxel/tags/vga-20190529-pull-request' into staging

vga: add vhost-user-gpu.

# gpg: Signature made Wed 29 May 2019 05:40:02 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/vga-20190529-pull-request:
  hw/display: add vhost-user-vga & gpu-pci
  virtio-gpu: split virtio-gpu-pci & virtio-vga
  virtio-gpu: split virtio-gpu, introduce virtio-gpu-base
  spice-app: fix running when !CONFIG_OPENGL
  contrib: add vhost-user-gpu
  util: compile drm.o on posix
  virtio-gpu: add a pixman helper header
  virtio-gpu: add bswap helpers header
  vhost-user: add vhost_user_gpu_set_socket()
  virtio-gpu: add sanity check

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-05-30 13:10:00 +01:00
Jie Wang 31618958cc vhost: fix incorrect print type
fix incorrect print type in vhost_virtqueue_stop

Signed-off-by: Jie Wang <wangjie88@huawei.com>
Message-Id: <1556605773-42019-1-git-send-email-wangjie88@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-05-29 18:00:57 -04:00
Jie Wang c39eb88da1 vhost: remove the dead code
remove the dead code

Signed-off-by: Jie Wang <wangjie88@huawei.com>
Message-Id: <1556604614-32081-1-git-send-email-wangjie88@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-05-29 18:00:57 -04:00
Marc-André Lureau bd2e44fee4 vhost-user: add vhost_user_gpu_set_socket()
Add a new vhost-user message to give a unix socket to a vhost-user
backend for GPU display updates.

Back when I started that work, I added a new GPU channel because the
vhost-user protocol wasn't bidirectional. Since then, there is a
vhost-user-slave channel for the slave to send requests to the master.
We could extend it with GPU messages. However, the GPU protocol is
quite orthogonal to vhost-user, thus I chose to have a new dedicated
channel.

See vhost-user-gpu.rst for the protocol details.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-2-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-29 06:29:07 +02:00
Philippe Mathieu-Daudé 3d2fc923ec hw/virtio: Use object_initialize_child for correct reference counting
As explained in commit aff39be0ed97:

  Both functions, object_initialize() and object_property_add_child()
  increase the reference counter of the new object, so one of the
  references has to be dropped afterwards to get the reference
  counting right. Otherwise the child object will not be properly
  cleaned up when the parent gets destroyed.
  Thus let's use now object_initialize_child() instead to get the
  reference counting here right.

This patch was generated using the following Coccinelle script:

 @use_object_initialize_child@
 expression parent_obj;
 expression child_ptr;
 expression child_name;
 expression child_type;
 expression child_size;
 expression errp;
 @@
 (
 -   object_initialize(child_ptr, child_size, child_type);
 +   object_initialize_child(parent_obj, child_name,  child_ptr, child_size,
 +                           child_type, &error_abort, NULL);
     ... when != parent_obj
 -   object_property_add_child(parent_obj, child_name, OBJECT(child_ptr), NULL);
     ...
 ?-  object_unref(OBJECT(child_ptr));
 |
 -   object_initialize(child_ptr, child_size, child_type);
 +   object_initialize_child(parent_obj, child_name,  child_ptr, child_size,
 +                            child_type, errp, NULL);
     ... when != parent_obj
 -   object_property_add_child(parent_obj, child_name, OBJECT(child_ptr), errp);
     ...
 ?-  object_unref(OBJECT(child_ptr));
 )

While the object_initialize() function doesn't take an
'Error *errp' argument, the object_initialize_child() does.
Since this code is used when a machine is created (and is not
yet running), we deliberately choose to use the &error_abort
argument instead of ignoring errors if an object creation failed.

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Inspired-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190507163416.24647-4-philmd@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2019-05-24 15:29:02 -03:00
Boxuan Li da1804d17a hw/virtio/virtio-mmio: Convert DPRINTF to trace and log
Use traces for debug message and qemu_log_mask for errors.

Signed-off-by: Boxuan Li <liboxuan@connect.hku.hk>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Message-Id: <20190503154424.73933-1-liboxuan@connect.hku.hk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-05-22 15:33:20 +02:00
David Gibson b0e5196a52 pci: Simplify pci_bus_is_root()
pci_bus_is_root() currently relies on a method in the PCIBusClass.
But it's always known if a PCI bus is a root bus when we create it, so
using a dynamic method is overkill.

This replaces it with an IS_ROOT bit in a new flags field, which is set on
root buses and otherwise clear.  As a bonus this removes the special
is_root logic from pci_expander_bridge, since it already creates its bus
as a root bus.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20190424041959.4087-3-david@gibson.dropbear.id.au>
2019-05-20 18:40:02 -04:00
Xie Yongji 7dc7f12297 virtio: Use started flag in virtio_vmstate_change()
Currently, we use DRIVER_OK status bit to check whether guest
driver has started the device in virtio_vmstate_change(). But it's
not the case for virtio 1.0 transitional devices. If migration completes
between kicking virtqueue and setting VIRTIO_CONFIG_S_DRIVER_OK, guest
may be hung. So here we use started flag to check guest state instead.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190320112646.3712-3-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-20 18:40:02 -04:00
Xie Yongji badaf79cfd virtio: Introduce started flag to VirtioDevice
The virtio 1.0 transitional devices support driver uses the device
before setting the DRIVER_OK status bit. So we introduce a started
flag to indicate whether driver has started the device or not.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190320112646.3712-2-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-20 18:40:02 -04:00
Daniel P. Berrangé f2784eed30 hw: report invalid disable-legacy|modern usage for virtio-1-only devs
A number of virtio devices (gpu, crypto, mouse, keyboard, tablet) only
support the virtio-1 (aka modern) mode. Currently if the user launches
QEMU, setting those devices to enable legacy mode, QEMU will silently
create them in modern mode, ignoring the user's (mistaken) request.

This patch introduces proper data validation so that an attempt to
configure a virtio-1-only devices in legacy mode gets reported as an
error to the user.

Checking this required introduction of a new field to explicitly track
what operating model is to be used for a device, separately from the
disable_modern and disable_legacy fields that record the user's
requested configuration.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190215103239.28640-2-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-20 18:40:02 -04:00
Jason Wang 23bfaf77fa vhost_net: don't set backend for the uninitialized virtqueue
We used to set backend unconditionally, this won't work for some
guests (e.g windows driver) who may not initialize all virtqueues. For
kernel backend, this will fail since it may try to validate the rings
during setting backend.

Fixing this by simply skipping the backend set when we find desc is
not ready.

Reviewed-by: Michael S. Tsirkin<mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2019-05-17 17:00:12 +08:00
Gerd Hoffmann d923e30578 virtio-input-host-pci: cleanup types
virtio input is virtio-1.0 only, so we don't need the -transitional and
-non-transitional variants.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190510105137.17481-1-kraxel@redhat.com
2019-05-13 08:49:30 +02:00
Marc-André Lureau 9c4d05b741 Add vhost-user-input-pci
Add a new virtio-input device, which connects to a vhost-user
backend.

Instead of reading configuration directly from an input device /
evdev (like virtio-input-host), it reads it over vhost-user protocol
with {SET,GET}_CONFIG messages. The vhost-user-backend handles the
queues & events setup.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190503130034.24916-5-marcandre.lureau@redhat.com

[ kraxel: drop -{non-,}transitional variants ]
[ kraxel: fix "make check" on !linux ]

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-10 14:52:47 +02:00
Markus Armbruster 500016e5db trace-events: Shorten file names in comments
We spell out sub/dir/ in sub/dir/trace-events' comments pointing to
source files.  That's because when trace-events got split up, the
comments were moved verbatim.

Delete the sub/dir/ part from these comments.  Gets rid of several
misspellings.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190314180929.27722-3-armbru@redhat.com
Message-Id: <20190314180929.27722-3-armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-03-22 16:18:07 +00:00
Xie Yongji 5ad204bf2a vhost-user: Support transferring inflight buffer between qemu and backend
This patch introduces two new messages VHOST_USER_GET_INFLIGHT_FD
and VHOST_USER_SET_INFLIGHT_FD to support transferring a shared
buffer between qemu and backend.

Firstly, qemu uses VHOST_USER_GET_INFLIGHT_FD to get the
shared buffer from backend. Then qemu should send it back
through VHOST_USER_SET_INFLIGHT_FD each time we start vhost-user.

This shared buffer is used to track inflight I/O by backend.
Qemu should retrieve a new one when vm reset.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Chai Wen <chaiwen@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190228085355.9614-2-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau 9af84c02e2 vhost-user: split vhost_user_read()
Split vhost_user_read(), so only header can be read with
vhost_user_read_header().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190308140454.32437-8-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 22:31:21 -04:00
Marc-André Lureau 917d7dd72a vhost-user: wrap some read/write with retry handling
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20190308140454.32437-6-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
Marc-André Lureau 0b99f22461 vhost-user: simplify vhost_user_init/vhost_user_cleanup
Take a VhostUserState* that can be pre-allocated, and initialize it
with the associated chardev.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
Message-Id: <20190308140454.32437-4-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
David Gibson 596546fe9e virtio-balloon: Restore MADV_WILLNEED hint on balloon deflate
Prior to f6deb6d9 "virtio-balloon: Remove unnecessary MADV_WILLNEED on
deflate", the balloon device issued an madvise() MADV_WILLNEED on
pages removed from the balloon.  That would hint to the host kernel
that the pages were likely to be needed by the guest in the near
future.

It's unclear if this is actually valuable or not, and so f6deb6d9
removed this, essentially ignoring balloon deflate requests.  However,
concerns have been raised that this might cause a performance
regression by causing extra latency for the guest in certain
configurations.

So, until we can get actual benchmark data to see if that's the case,
this restores the old behaviour, issuing a MADV_WILLNEED when a page is
removed from the balloon.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20190306030601.21986-4-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
David Gibson b27b323914 virtio-balloon: Fix possible guest memory corruption with inflates & deflates
This fixes a balloon bug with a nasty consequence - potentially
corrupting guest memory - but which is extremely unlikely to be
triggered in practice.

The balloon always works in 4kiB units, but the host could have a
larger page size on certain platforms.  Since ed48c59 "virtio-balloon:
Safely handle BALLOON_PAGE_SIZE < host page size" we've handled this
by accumulating requests to balloon 4kiB subpages until they formed a
full host page.  Since f6deb6d "virtio-balloon: Remove unnecessary
MADV_WILLNEED on deflate" we essentially ignore deflate requests.

Suppose we have a host with 8kiB pages, and one host page has subpages
A & B.  If we get this sequence of events -
	inflate A
	deflate A
	inflate B
- the current logic will discard the whole host page.  That's
incorrect because the guest has deflated subpage A, and could have
written important data to it.

This patch fixes the problem by adjusting our state information about
partially ballooned host pages when deflate requests are received.

Fixes: ed48c59 "virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size"

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20190306030601.21986-3-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2019-03-12 21:22:31 -04:00
David Gibson 301cf2a8dd virtio-balloon: Don't mismatch g_malloc()/free (CID 1399146)
ed48c59875 "virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host
page size" introduced a new temporary data structure which tracks 4kiB
chunks which have been inserted into the balloon by the guest but
don't yet form a full host page which we can discard.

Unfortunately, I had a thinko and allocated that structure with
g_malloc0() but freed it with a plain free() rather than g_free().
This corrects the problem.

Fixes: ed48c59875
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20190306030601.21986-2-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2019-03-12 21:22:31 -04:00
Wei Wang ae440bd14c virtio-balloon: fix a use-after-free case
The elem could theorically contain both outbuf and inbufs. We move the
free operation to the end of this function to avoid using elem->in_sg
while elem has been freed.

Fixes: c13c4153f7
("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Message-Id: <1552383280-4122-1-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-12 21:22:31 -04:00
Gerd Hoffmann 8ea90ee690 virtio: add class_size to VirtioPCIDeviceTypeInfo
Needed when VirtioPCIClass subclasses have their own
class struct with some extra fields.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20190307080244.9011-2-kraxel@redhat.com
2019-03-11 08:04:12 +01:00
Thomas Huth 9e5c2056d1 s390x: express dependencies with Kconfig
Instead of hard-coding all config switches in the config file
default-configs/s390x-softmmu.mak, let's use the new Kconfig files
to express the necessary dependencies: The S390_CCW_VIRTIO config switch
for the "s390-ccw-virtio" machine now selects all non-optional devices.

And since we already have the VIRTIO_PCI and VIRTIO_MMIO config switches
for the other two virtio transports, this patch also introduces a new
config switch VIRTIO_CCW for the third, s390x-specific virtio transport,
so that all three virtio transports are now handled in the same way.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07 21:46:19 +01:00
Yang Zhong b42075bb77 virtio: express virtio dependencies with Kconfig
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190123065618.3520-42-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07 21:45:53 +01:00
Paolo Bonzini 7c28b925b7 build: convert pci.mak to Kconfig
Instead of including the same list of devices for each target,
set CONFIG_PCI to true, and make the devices default to present
whenever PCI is available.  However, s390x does not want all the
PCI devices, so there is a separate symbol to enable them.

Done mostly with the following script:

  while read i; do
     i=${i%=y}; i=${i#CONFIG_}
     sed -i -e'/^config '$i'$/!b' -en \
            -e'a\' -e'    default y if PCI_DEVICES\' -e'    depends on PCI' \
          `grep -lw $i hw/*/Kconfig`
  done < default-configs/pci.mak

followed by replacing a few "depends on" clauses with "select"
whenever the symbol is not really related to PCI.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190123065618.3520-31-yang.zhong@intel.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07 21:45:53 +01:00
Paolo Bonzini 82f5181777 kconfig: introduce kconfig files
The Kconfig files were generated mostly with this script:

  for i in `grep -ho CONFIG_[A-Z0-9_]* default-configs/* | sort -u`; do
    set fnord `git grep -lw $i -- 'hw/*/Makefile.objs' `
    shift
    if test $# = 1; then
      cat >> $(dirname $1)/Kconfig << EOF
config ${i#CONFIG_}
    bool

EOF
      git add $(dirname $1)/Kconfig
    else
      echo $i $*
    fi
  done
  sed -i '$d' hw/*/Kconfig
  for i in hw/*; do
    if test -d $i && ! test -f $i/Kconfig; then
      touch $i/Kconfig
      git add $i/Kconfig
    fi
  done

Whenever a symbol is referenced from multiple subdirectories, the
script prints the list of directories that reference the symbol.
These symbols have to be added manually to the Kconfig files.

Kconfig.host and hw/Kconfig were created manually.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20190123065618.3520-27-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-03-07 21:45:53 +01:00
Wei Wang c13c4153f7 virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT
The new feature enables the virtio-balloon device to receive hints of
guest free pages from the free page vq.

A notifier is registered to the migration precopy notifier chain. The
notifier calls free_page_start after the migration thread syncs the dirty
bitmap, so that the free page optimization starts to clear bits of free
pages from the bitmap. It calls the free_page_stop before the migration
thread syncs the bitmap, which is the end of the current round of ram
save. The free_page_stop is also called to stop the optimization in the
case when there is an error occurred in the process of ram saving.

Note: balloon will report pages which were free at the time of this call.
As the reporting happens asynchronously, dirty bit logging must be
enabled before this free_page_start call is made. Guest reporting must be
disabled before the migration dirty bitmap is synchronized.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-8-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: Dropped kernel header update, fixed up CMD_ID_* name change
2019-03-06 10:49:18 +00:00
Peter Maydell 1d31f1872b pci, pc, virtio: fixes, cleanups, tests
Lots of work on tests: BiosTablesTest UEFI app,
 vhost-user testing for non-Linux hosts.
 Misc cleanups and fixes all over the place
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

pci, pc, virtio: fixes, cleanups, tests

Lots of work on tests: BiosTablesTest UEFI app,
vhost-user testing for non-Linux hosts.
Misc cleanups and fixes all over the place

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 22 Feb 2019 15:51:40 GMT
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (26 commits)
  pci: Sanity test minimum downstream LNKSTA
  hw/smbios: fix offset of type 3 sku field
  pci: Move NVIDIA vendor id to the rest of ids
  virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size
  virtio-balloon: Use ram_block_discard_range() instead of raw madvise()
  virtio-balloon: Rework ballon_page() interface
  virtio-balloon: Corrections to address verification
  virtio-balloon: Remove unnecessary MADV_WILLNEED on deflate
  i386/kvm: ignore masked irqs when update msi routes
  contrib/vhost-user-blk: fix the compilation issue
  Revert "contrib/vhost-user-blk: fix the compilation issue"
  pc-dimm: use same mechanism for [get|set]_addr
  tests/data: introduce "uefi-boot-images" with the "bios-tables-test" ISOs
  tests/uefi-test-tools: add build scripts
  tests: introduce "uefi-test-tools" with the BiosTablesTest UEFI app
  roms: build the EfiRom utility from the roms/edk2 submodule
  roms: add the edk2 project as a git submodule
  vhost-user-test: create a temporary directory per TestServer
  vhost-user-test: small changes to init_hugepagefs
  vhost-user-test: create a main loop per TestServer
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-03-04 11:04:31 +00:00
David Gibson ed48c59875 virtio-balloon: Safely handle BALLOON_PAGE_SIZE < host page size
The virtio-balloon always works in units of 4kiB (BALLOON_PAGE_SIZE), but
we can only actually discard memory in units of the host page size.

Now, we handle this very badly: we silently ignore balloon requests that
aren't host page aligned, and for requests that are host page aligned we
discard the entire host page.  The latter can corrupt guest memory if its
page size is smaller than the host's.

The obvious choice would be to disable the balloon if the host page size is
not 4kiB.  However, that would break the special case where host and guest
have the same page size, but that's larger than 4kiB.  That case currently
works by accident[1] - and is used in practice on many production POWER
systems where 64kiB has long been the Linux default page size on both host
and guest.

To make the balloon safe, without breaking that useful special case, we
need to accumulate 4kiB balloon requests until we have a whole contiguous
host page to discard.

We could in principle do that across all guest memory, but it would require
a large bitmap to track.  This patch represents a compromise: we track
ballooned subpages for a single contiguous host page at a time.  This means
that if the guest discards all 4kiB chunks of a host page in succession,
we will discard it.  This is the expected behaviour in the (host page) ==
(guest page) != 4kiB case we want to support.

If the guest scatters 4kiB requests across different host pages, we don't
discard anything, and issue a warning.  Not ideal, but at least we don't
corrupt guest memory as the previous version could.

Warning reporting is kind of a compromise here.  Determining whether we're
in a problematic state at realize() time is tricky, because we'd have to
look at the host pagesizes of all memory backends, but we can't really know
if some of those backends could be for special purpose memory that's not
subject to ballooning.

Reporting only when the guest tries to balloon a partial page also isn't
great because if the guest page size happens to line up it won't indicate
that we're in a non ideal situation.  It could also cause alarming repeated
warnings whenever a migration is attempted.

So, what we do is warn the first time the guest attempts balloon a partial
host page, whether or not it will end up ballooning the rest of the page
immediately afterwards.

[1] Because when the guest attempts to balloon a page, it will submit
    requests for each 4kiB subpage.  Most will be ignored, but the one
    which happens to be host page aligned will discard the whole lot.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20190214043916.22128-6-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-22 10:51:31 -05:00
Stefano Garzarella ba550851f5 virtio-net: make VirtIOFeature usable for other virtio devices
In order to use VirtIOFeature also in other virtio devices, we move
its declaration and the endof() macro (renamed in virtio_endof())
in virtio.h.
We add virtio_feature_get_config_size() function to iterate the array
of VirtIOFeature and to return the config size depending on the
features enabled. (as virtio_net_set_config_size() did)

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20190221103314.58500-5-sgarzare@redhat.com
Message-Id: <20190221103314.58500-5-sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-02-22 09:42:16 +00:00
David Gibson dbe1a27745 virtio-balloon: Use ram_block_discard_range() instead of raw madvise()
Currently, virtio-balloon uses madvise() with MADV_DONTNEED to actually
discard RAM pages inserted into the balloon.  This is basically a Linux
only interface (MADV_DONTNEED exists on some other platforms, but doesn't
always have the same semantics).  It also doesn't work on hugepages and has
some other limitations.

It turns out that postcopy also needs to discard chunks of memory, and uses
a better interface for it: ram_block_discard_range().  It doesn't cover
every case, but it covers more than going direct to madvise() and this
gives us a single place to update for more possibilities in future.

There are some subtleties here to maintain the current balloon behaviour:

* For now, we just ignore requests to balloon in a hugepage backed region.
  That matches current behaviour, because MADV_DONTNEED on a hugepage would
  simply fail, and we ignore the error.

* If host page size is > BALLOON_PAGE_SIZE we can frequently call this on
  non-host-page-aligned addresses.  These would also fail in madvise(),
  which we then ignored.  ram_block_discard_range() error_report()s calls
  on unaligned addresses, so we explicitly check that case to avoid
  spamming the logs.

* We now call ram_block_discard_range() with the *host* page size, whereas
  we previously called madvise() with BALLOON_PAGE_SIZE.  Surprisingly,
  this also matches existing behaviour.  Although the kernel fails madvise
  on unaligned addresses, it will round unaligned sizes *up* to the host
  page size.  Yes, this means that if BALLOON_PAGE_SIZE < guest page size
  we can incorrectly discard more memory than the guest asked us to.  I'm
  planning to address that soon.

Errors other than the ones discussed above, will now be reported by
ram_block_discard_range(), rather than silently ignored, which means we
have a much better chance of seeing when something is going wrong.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20190214043916.22128-5-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-21 12:28:41 -05:00
David Gibson e9550234d7 virtio-balloon: Rework ballon_page() interface
This replaces the balloon_page() internal interface with
ballon_inflate_page(), with a slightly different interface.  The new
interface will make future alterations simpler.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20190214043916.22128-4-david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-21 12:28:41 -05:00