Re: [Qemu-devel] [PATCH] pvevent: pvevent device driver

[Blue Swirl]

On Thu, Mar 14, 2013 at 8:51 AM, Hu Tao <address@hidden> wrote:
> pvevent device is a qemu simulated device through which guest panic
> event is sent to host.
>
> ref: http://lists.nongnu.org/archive/html/qemu-devel/2013-03/msg02293.html
>
> Signed-off-by: Hu Tao <address@hidden>
> ---
>  drivers/platform/x86/Kconfig   |   7 +++
>  drivers/platform/x86/Makefile  |   2 +
>  drivers/platform/x86/pvevent.c | 115 
> +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 124 insertions(+)
>  create mode 100644 drivers/platform/x86/pvevent.c
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 7ab0b2f..369135e 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -768,4 +768,11 @@ config APPLE_GMUX
>           graphics as well as the backlight. Currently only backlight
>           control is supported by the driver.
>
> +config PVEVENT
> +       tristate "pvevent device support"
> +       depends on ACPI
> +       ---help---
> +         This driver provides support for pvevent device, which is a qemu
> +         simulated device through which guest panic event is sent to host.
> +
>  endif # X86_PLATFORM_DEVICES
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index bf7e4f9..8779396 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -50,3 +50,5 @@ obj-$(CONFIG_INTEL_MID_POWER_BUTTON)  += 
> intel_mid_powerbtn.o
>  obj-$(CONFIG_INTEL_OAKTRAIL)   += intel_oaktrail.o
>  obj-$(CONFIG_SAMSUNG_Q10)      += samsung-q10.o
>  obj-$(CONFIG_APPLE_GMUX)       += apple-gmux.o
> +
> +obj-$(CONFIG_PVEVENT)           += pvevent.o
> diff --git a/drivers/platform/x86/pvevent.c b/drivers/platform/x86/pvevent.c
> new file mode 100644
> index 0000000..00ef7f4
> --- /dev/null
> +++ b/drivers/platform/x86/pvevent.c
> @@ -0,0 +1,115 @@
> +/*
> + *  pvevent.c - pvevent Device Support
> + *
> + *  Copyright (C) 2013 Fujitsu.
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation; either version 2 of the License, or
> + *  (at your option) any later version.
> + *
> + *  This program is distributed in the hope that it will be useful,
> + *  but WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + *  GNU General Public License for more details.
> + *
> + *  You should have received a copy of the GNU General Public License
> + *  along with this program; if not, write to the Free Software
> + *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

Current address of FSF is:

51 Franklin Street, Fifth Floor
Boston, MA 02110-1301
USA

I'd use the web version recommended by FSF.

> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/types.h>
> +#include <acpi/acpi_bus.h>
> +#include <acpi/acpi_drivers.h>
> +
> +MODULE_AUTHOR("Hu Tao <address@hidden>");
> +MODULE_DESCRIPTION("pvevent device driver");
> +MODULE_LICENSE("GPL");
> +
> +static int pvevent_add(struct acpi_device *device);
> +static int pvevent_remove(struct acpi_device *device);
> +
> +static const struct acpi_device_id pvevent_device_ids[] = {
> +       { "MSFT0001", 0},
> +       { "", 0},
> +};
> +MODULE_DEVICE_TABLE(acpi, pvevent_device_ids);
> +
> +#define PVEVENT_PANICKED       (1 << 0)
> +
> +static acpi_handle handle;
> +
> +static struct acpi_driver pvevent_driver = {
> +       .name =         "pvevent",
> +       .class =        "QEMU",
> +       .ids =          pvevent_device_ids,
> +       .ops =          {
> +                               .add =          pvevent_add,
> +                               .remove =       pvevent_remove,
> +                       },
> +       .owner =        THIS_MODULE,
> +};
> +
> +static void
> +pvevent_send_event(unsigned int event)
> +{
> +       union acpi_object arg;
> +       struct acpi_object_list arg_list;
> +
> +       if (!handle)
> +               return;
> +
> +       arg.type = ACPI_TYPE_INTEGER;
> +       arg.integer.value = event;
> +
> +       arg_list.count = 1;
> +       arg_list.pointer = &arg;
> +
> +       acpi_evaluate_object(handle, "WRPT", &arg_list, NULL);
> +}
> +
> +static int
> +pvevent_panic_notify(struct notifier_block *nb, unsigned long code,
> +                    void *unused)
> +{
> +       pvevent_send_event(PVEVENT_PANICKED);
> +       return NOTIFY_DONE;
> +}
> +
> +static struct notifier_block pvevent_panic_nb = {
> +       .notifier_call = pvevent_panic_notify,
> +};
> +
> +static int pvevent_add(struct acpi_device *device)
> +{
> +       acpi_status status;
> +       u64 ret;
> +
> +       status = acpi_evaluate_integer(device->handle, "_STA", NULL,
> +                                      &ret);
> +
> +       if (ACPI_FAILURE(status) || !ret)
> +               return -ENODEV;
> +
> +       handle = device->handle;
> +       atomic_notifier_chain_register(&panic_notifier_list,
> +                                      &pvevent_panic_nb);
> +
> +       return 0;
> +}
> +
> +static int pvevent_remove(struct acpi_device *device)
> +{
> +
> +       atomic_notifier_chain_unregister(&panic_notifier_list,
> +                                        &pvevent_panic_nb);
> +       handle = NULL;
> +       return 0;
> +}
> +
> +module_acpi_driver(pvevent_driver);
> --
> 1.8.1.4
>