Hi
On Wed, Dec 2, 2020 at 12:23 AM Jagannathan Raman <jag.ra...@oracle.com>
wrote:
> From: Elena Ufimtseva <elena.ufimts...@oracle.com>
>
> Defines a PCI Device proxy object as a child of TYPE_PCI_DEVICE.
>
> Signed-off-by: Elena Ufimtseva <elena.ufimts...@oracle.com>
> Signed-off-by: Jagannathan Raman <jag.ra...@oracle.com>
> Signed-off-by: John G Johnson <john.g.john...@oracle.com>
> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> include/hw/remote/proxy.h | 36 +++++++++++++++++
> hw/remote/proxy.c | 98
> +++++++++++++++++++++++++++++++++++++++++++++++
> MAINTAINERS | 2 +
> hw/remote/meson.build | 1 +
> 4 files changed, 137 insertions(+)
> create mode 100644 include/hw/remote/proxy.h
> create mode 100644 hw/remote/proxy.c
>
> diff --git a/include/hw/remote/proxy.h b/include/hw/remote/proxy.h
> new file mode 100644
> index 0000000..923432a
> --- /dev/null
> +++ b/include/hw/remote/proxy.h
> @@ -0,0 +1,36 @@
> +/*
> + * Copyright © 2018, 2020 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#ifndef PROXY_H
> +#define PROXY_H
>
+
> +#include "hw/pci/pci.h"
> +#include "io/channel.h"
> +
> +#define TYPE_PCI_PROXY_DEV "x-pci-proxy-dev"
> +
> +#define PCI_PROXY_DEV(obj) \
> + OBJECT_CHECK(PCIProxyDev, (obj), TYPE_PCI_PROXY_DEV)
> +typedef struct PCIProxyDev PCIProxyDev;
> +
> +struct PCIProxyDev {
> + PCIDevice parent_dev;
> + char *fd;
> +
> + /*
> + * Mutex used to protect the QIOChannel fd from
> + * the concurrent access by the VCPUs since proxy
> + * blocks while awaiting for the replies from the
> + * process remote.
> + */
> + QemuMutex io_mutex;
> + QIOChannel *ioc;
> + Error *migration_blocker;
> +};
> +
> +#endif /* PROXY_H */
> diff --git a/hw/remote/proxy.c b/hw/remote/proxy.c
> new file mode 100644
> index 0000000..29100bc
> --- /dev/null
> +++ b/hw/remote/proxy.c
> @@ -0,0 +1,98 @@
> +/*
> + * Copyright © 2018, 2020 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> later.
> + * See the COPYING file in the top-level directory.
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu-common.h"
> +
> +#include "hw/remote/proxy.h"
> +#include "hw/pci/pci.h"
> +#include "qapi/error.h"
> +#include "io/channel-util.h"
> +#include "hw/qdev-properties.h"
> +#include "monitor/monitor.h"
> +#include "migration/blocker.h"
> +
> +static void proxy_set_socket(PCIProxyDev *pdev, int fd, Error **errp)
> +{
> + pdev->ioc = qio_channel_new_fd(fd, errp);
> +}
>
That one line function (called once) should be inlined.
+
> +static Property proxy_properties[] = {
> + DEFINE_PROP_STRING("fd", PCIProxyDev, fd),
> + DEFINE_PROP_END_OF_LIST(),
> +};
> +
>
Generally we put properties just above class_init, where it is used.
+static void pci_proxy_dev_realize(PCIDevice *device, Error **errp)
> +{
>
(errp shouldn't be NULL, but ERRP_GUARD would be safer)
+ PCIProxyDev *dev = PCI_PROXY_DEV(device);
> + int fd;
> +
> + if (dev->fd) {
> + fd = monitor_fd_param(monitor_cur(), dev->fd, errp);
> + if (fd == -1) {
> + error_prepend(errp, "proxy: unable to parse fd: ");
> + return;
> + }
> + proxy_set_socket(dev, fd, errp);
> + } else {
> + error_setg(errp, "fd parameter not specified for %s",
> + DEVICE(device)->id);
> + return;
>
We prefer early return, to keep the code easy to read.
if (!dev->fd) {
return error...
}
the_normal_thing();
...
+ }
> +
> + error_setg(&dev->migration_blocker, "%s does not support migration",
> + TYPE_PCI_PROXY_DEV);
> + if (migrate_add_blocker(dev->migration_blocker, errp)) {
> + error_free(dev->migration_blocker);
>
leave that free to dev_exit() ?
> + error_free(*errp);
> + dev->migration_blocker = NULL;
> + error_setg(errp, "Failed to set migration blocker");
>
Why not use the error from migrate_add_blocker?
+ }
> +
> + qemu_mutex_init(&dev->io_mutex);
> + qio_channel_set_blocking(dev->ioc, true, NULL);
> +}
> +
> +static void pci_proxy_dev_exit(PCIDevice *pdev)
> +{
> + PCIProxyDev *dev = PCI_PROXY_DEV(pdev);
> +
> + qio_channel_close(dev->ioc, NULL);
>
on early return in realize, dev->ioc is NULL. This will crash.
+
> + migrate_del_blocker(dev->migration_blocker);
>
So is migration_blocker, but this should be safe with NULL
> +
> + error_free(dev->migration_blocker);
>
+}
> +
> +static void pci_proxy_dev_class_init(ObjectClass *klass, void *data)
> +{
> + DeviceClass *dc = DEVICE_CLASS(klass);
> + PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> +
> + k->realize = pci_proxy_dev_realize;
> + k->exit = pci_proxy_dev_exit;
> + device_class_set_props(dc, proxy_properties);
> +}
> +
> +static const TypeInfo pci_proxy_dev_type_info = {
> + .name = TYPE_PCI_PROXY_DEV,
> + .parent = TYPE_PCI_DEVICE,
> + .instance_size = sizeof(PCIProxyDev),
> + .class_init = pci_proxy_dev_class_init,
> + .interfaces = (InterfaceInfo[]) {
> + { INTERFACE_CONVENTIONAL_PCI_DEVICE },
> + { },
> + },
> +};
> +
> +static void pci_proxy_dev_register_types(void)
> +{
> + type_register_static(&pci_proxy_dev_type_info);
> +}
> +
> +type_init(pci_proxy_dev_register_types)
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 24cb36e..ebd1d1d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3148,6 +3148,8 @@ F: include/hw/remote/remote-obj.h
> F: hw/remote/remote-obj.c
> F: include/hw/remote/memory.h
> F: hw/remote/memory.c
> +F: hw/remote/proxy.c
> +F: include/hw/remote/proxy.h
>
> Build and test automation
> -------------------------
> diff --git a/hw/remote/meson.build b/hw/remote/meson.build
> index 64da16c..569cd20 100644
> --- a/hw/remote/meson.build
> +++ b/hw/remote/meson.build
> @@ -4,6 +4,7 @@ remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true:
> files('machine.c'))
> remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true:
> files('mpqemu-link.c'))
> remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('message.c'))
> remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('remote-obj.c'))
> +remote_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('proxy.c'))
>
> specific_ss.add(when: 'CONFIG_MULTIPROCESS', if_true: files('memory.c'))
>
> --
> 1.8.3.1
>
>
--
Marc-André Lureau
