[libvirt] [PATCH 5/8] Split reprobe action from the virPCIUnbindFromStub into a new function

[Andrea Bolognani]

On Fri, 2015-10-30 at 04:59 +0530, Shivaprasad G Bhat wrote:
> The reprobe needs to be called multiple times for vfio devices for each
> device in the iommu group in future patch. So split the reprobe into a
> new function. No functional change.
> 
> Signed-off-by: Shivaprasad G Bhat <sbhat at linux.vnet.ibm.com>
> ---
>  src/util/virpci.c |   54 +++++++++++++++++++++++++++++++----------------------
>  1 file changed, 32 insertions(+), 22 deletions(-)
> 
> diff --git a/src/util/virpci.c b/src/util/virpci.c
> index eba285a..2709ddd 100644
> --- a/src/util/virpci.c
> +++ b/src/util/virpci.c
> @@ -1097,6 +1097,37 @@ static bool virPCIIsAKnownStub(char *driver)
>      return ret;
>  }
>  
> +static int virPCIDeviceReprobeHostDriver(virPCIDevicePtr dev, char *driver, char *drvdir)
> +{
> +    char *path = NULL;
> +    int result = -1;
> +
> +    if (!dev->reprobe)
> +        return 0;
> +
> +    /* Trigger a re-probe of the device is not in the stub's dynamic
> +     * ID table. If the stub is available, but 'remove_id' isn't
> +     * available, then re-probing would just cause the device to be
> +     * re-bound to the stub.
> +     */
> +    if (driver && !(path = virPCIDriverFile(driver, "remove_id")))
> +        goto cleanup;
> +
> +    if (!driver || !virFileExists(drvdir) || virFileExists(path)) {
> +        if (virFileWriteStr(PCI_SYSFS "drivers_probe", dev->name, 0) < 0) {
> +            virReportSystemError(errno,
> +                                 _("Failed to trigger a re-probe for PCI device '%s'"),
> +                                 dev->name);
> +            goto cleanup;
> +        }
> +    }
> +    result = 0;
> + cleanup:
> +    VIR_FREE(path);
> +    dev->reprobe = false;
> +    return result;
> +}
> +
>  static int
>  virPCIDeviceUnbindFromStub(virPCIDevicePtr dev)
>  {
> @@ -1144,28 +1175,8 @@ virPCIDeviceUnbindFromStub(virPCIDevicePtr dev)
>      dev->remove_slot = false;
>  
>   reprobe:
> -    if (!dev->reprobe) {
> -        result = 0;
> +    if (virPCIDeviceReprobeHostDriver(dev, driver, drvdir) < 0)
>          goto cleanup;
> -    }

This actually introduces a flow change in the function:
before this patch, when dev->reprobe is false we set
result = 0 and jumped to cleanup, while now
virPCIDeviceReprobeHostDriver() returns 0 and the rest
of virPCIDeviceUnbindFromStub() is executed.

I would leave the check for the value of dev->reprobe
and setting it to false in cleanup out of
virPCIDeviceReprobeHostDriver().

> -
> -    /* Trigger a re-probe of the device is not in the stub's dynamic
> -     * ID table. If the stub is available, but 'remove_id' isn't
> -     * available, then re-probing would just cause the device to be
> -     * re-bound to the stub.
> -     */
> -    VIR_FREE(path);
> -    if (driver && !(path = virPCIDriverFile(driver, "remove_id")))
> -        goto cleanup;
> -
> -    if (!driver || !virFileExists(drvdir) || virFileExists(path)) {
> -        if (virFileWriteStr(PCI_SYSFS "drivers_probe", dev->name, 0) < 0) {
> -            virReportSystemError(errno,
> -                                 _("Failed to trigger a re-probe for PCI device '%s'"),
> -                                 dev->name);
> -            goto cleanup;
> -        }
> -    }
>  
>      result = 0;
>  
> @@ -1173,7 +1184,6 @@ virPCIDeviceUnbindFromStub(virPCIDevicePtr dev)
>      /* do not do it again */
>      dev->unbind_from_stub = false;
>      dev->remove_slot = false;
> -    dev->reprobe = false;
>  
>      VIR_FREE(drvdir);
>      VIR_FREE(path);

Cheers.

-- 
Andrea Bolognani
Software Engineer - Virtualization Team