Re: [PATCH v4 31/41] vfio/pci: Extract out a helper vfio_pci_get_pci_hot_reset_info

["Cédric Le Goater" <clg@redhat.com>]

On 11/2/23 08:12, Zhenzhong Duan wrote:
> This helper will be used by both legacy and iommufd backends.
> 
> No functional changes intended.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>


Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.


> ---
>   hw/vfio/pci.h |  3 +++
>   hw/vfio/pci.c | 54 +++++++++++++++++++++++++++++++++++----------------
>   2 files changed, 40 insertions(+), 17 deletions(-)
> 
> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
> index fba8737ab2..1006061afb 100644
> --- a/hw/vfio/pci.h
> +++ b/hw/vfio/pci.h
> @@ -218,6 +218,9 @@ void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr);
>   
>   extern const PropertyInfo qdev_prop_nv_gpudirect_clique;
>   
> +int vfio_pci_get_pci_hot_reset_info(VFIOPCIDevice *vdev,
> +                                    struct vfio_pci_hot_reset_info **info_p);
> +
>   int vfio_populate_vga(VFIOPCIDevice *vdev, Error **errp);
>   
>   int vfio_pci_igd_opregion_init(VFIOPCIDevice *vdev,
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index c62c02f7b6..eb55e8ae88 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -2445,22 +2445,13 @@ static bool vfio_pci_host_match(PCIHostDeviceAddress *addr, const char *name)
>       return (strcmp(tmp, name) == 0);
>   }
>   
> -static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
> +int vfio_pci_get_pci_hot_reset_info(VFIOPCIDevice *vdev,
> +                                    struct vfio_pci_hot_reset_info **info_p)
>   {
> -    VFIOGroup *group;
>       struct vfio_pci_hot_reset_info *info;
> -    struct vfio_pci_dependent_device *devices;
> -    struct vfio_pci_hot_reset *reset;
> -    int32_t *fds;
> -    int ret, i, count;
> -    bool multi = false;
> +    int ret, count;
>   
> -    trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
> -
> -    if (!single) {
> -        vfio_pci_pre_reset(vdev);
> -    }
> -    vdev->vbasedev.needs_reset = false;
> +    assert(info_p && !*info_p);
>   
>       info = g_malloc0(sizeof(*info));
>       info->argsz = sizeof(*info);
> @@ -2468,24 +2459,53 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
>       ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
>       if (ret && errno != ENOSPC) {
>           ret = -errno;
> +        g_free(info);
>           if (!vdev->has_pm_reset) {
>               error_report("vfio: Cannot reset device %s, "
>                            "no available reset mechanism.", vdev->vbasedev.name);
>           }
> -        goto out_single;
> +        return ret;
>       }
>   
>       count = info->count;
> -    info = g_realloc(info, sizeof(*info) + (count * sizeof(*devices)));
> -    info->argsz = sizeof(*info) + (count * sizeof(*devices));
> -    devices = &info->devices[0];
> +    info = g_realloc(info, sizeof(*info) + (count * sizeof(info->devices[0])));
> +    info->argsz = sizeof(*info) + (count * sizeof(info->devices[0]));
>   
>       ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_PCI_HOT_RESET_INFO, info);
>       if (ret) {
>           ret = -errno;
> +        g_free(info);
>           error_report("vfio: hot reset info failed: %m");
> +        return ret;
> +    }
> +
> +    *info_p = info;
> +    return 0;
> +}
> +
> +static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
> +{
> +    VFIOGroup *group;
> +    struct vfio_pci_hot_reset_info *info = NULL;
> +    struct vfio_pci_dependent_device *devices;
> +    struct vfio_pci_hot_reset *reset;
> +    int32_t *fds;
> +    int ret, i, count;
> +    bool multi = false;
> +
> +    trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
> +
> +    if (!single) {
> +        vfio_pci_pre_reset(vdev);
> +    }
> +    vdev->vbasedev.needs_reset = false;
> +
> +    ret = vfio_pci_get_pci_hot_reset_info(vdev, &info);
> +
> +    if (ret) {
>           goto out_single;
>       }
> +    devices = &info->devices[0];
>   
>       trace_vfio_pci_hot_reset_has_dep_devices(vdev->vbasedev.name);
>