Re: [PATCH v4 4/6] PCI: Expose reset type to users of pci_try_reset_function()

[Alex Williamson <alex.williamson@redhat.com>]

On Wed, 19 Sep 2018 16:30:35 +0000
Sinan Kaya <okaya@kernel.org> wrote:

> Looking to have more control between the users of the API vs. what the API
> can do internally. The new reset_type tells the PCI core about the bounds
> of the request.
> 
> Signed-off-by: Sinan Kaya <okaya@kernel.org>
> ---
>  drivers/pci/pci.c                  | 4 ++--
>  drivers/vfio/pci/vfio_pci.c        | 7 ++++---
>  drivers/vfio/pci/vfio_pci_config.c | 4 ++--
>  include/linux/pci.h                | 2 +-
>  4 files changed, 9 insertions(+), 8 deletions(-)

Acked-by: Alex Williamson <alex.williamson@redhat.com>

> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 63b5930d8fb1..4edf70a4d528 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -4852,7 +4852,7 @@ EXPORT_SYMBOL_GPL(pci_reset_function_locked);
>   *
>   * Same as above, except return -EAGAIN if unable to lock device.
>   */
> -int pci_try_reset_function(struct pci_dev *dev)
> +int pci_try_reset_function(struct pci_dev *dev, u32 reset_type)
>  {
>  	int rc;
>  
> @@ -4863,7 +4863,7 @@ int pci_try_reset_function(struct pci_dev *dev)
>  		return -EAGAIN;
>  
>  	pci_dev_save_and_disable(dev);
> -	rc = __pci_reset_function_locked(dev, PCI_RESET_ANY);
> +	rc = __pci_reset_function_locked(dev, reset_type);
>  	pci_dev_restore(dev);
>  	pci_dev_unlock(dev);
>  
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index cddb453a1ba5..fe7ada997c51 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -228,7 +228,7 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
>  		return ret;
>  
>  	/* If reset fails because of the device lock, fail this path entirely */
> -	ret = pci_try_reset_function(pdev);
> +	ret = pci_try_reset_function(pdev, PCI_RESET_ANY);
>  	if (ret == -EAGAIN) {
>  		pci_disable_device(pdev);
>  		return ret;
> @@ -376,7 +376,7 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev)
>  	 * Try to reset the device.  The success of this is dependent on
>  	 * being able to lock the device, which is not always possible.
>  	 */
> -	if (vdev->reset_works && !pci_try_reset_function(pdev))
> +	if (vdev->reset_works && !pci_try_reset_function(pdev, PCI_RESET_ANY))
>  		vdev->needs_reset = false;
>  
>  	pci_restore_state(pdev);
> @@ -844,7 +844,8 @@ static long vfio_pci_ioctl(void *device_data,
>  
>  	} else if (cmd == VFIO_DEVICE_RESET) {
>  		return vdev->reset_works ?
> -			pci_try_reset_function(vdev->pdev) : -EINVAL;
> +			pci_try_reset_function(vdev->pdev, PCI_RESET_ANY) :
> +			 -EINVAL;
>  
>  	} else if (cmd == VFIO_DEVICE_GET_PCI_HOT_RESET_INFO) {
>  		struct vfio_pci_hot_reset_info hdr;
> diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
> index 115a36f6f403..0d66bac66211 100644
> --- a/drivers/vfio/pci/vfio_pci_config.c
> +++ b/drivers/vfio/pci/vfio_pci_config.c
> @@ -831,7 +831,7 @@ static int vfio_exp_config_write(struct vfio_pci_device *vdev, int pos,
>  						 &cap);
>  
>  		if (!ret && (cap & PCI_EXP_DEVCAP_FLR))
> -			pci_try_reset_function(vdev->pdev);
> +			pci_try_reset_function(vdev->pdev, PCI_RESET_ANY);
>  	}
>  
>  	/*
> @@ -910,7 +910,7 @@ static int vfio_af_config_write(struct vfio_pci_device *vdev, int pos,
>  						&cap);
>  
>  		if (!ret && (cap & PCI_AF_CAP_FLR) && (cap & PCI_AF_CAP_TP))
> -			pci_try_reset_function(vdev->pdev);
> +			pci_try_reset_function(vdev->pdev, PCI_RESET_ANY);
>  	}
>  
>  	return count;
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 09aa99dd1c1b..4fdddcb85066 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1125,7 +1125,7 @@ int pcie_flr(struct pci_dev *dev);
>  int __pci_reset_function_locked(struct pci_dev *dev, u32 reset_type);
>  int pci_reset_function(struct pci_dev *dev, u32 reset_type);
>  int pci_reset_function_locked(struct pci_dev *dev, u32 reset_type);
> -int pci_try_reset_function(struct pci_dev *dev);
> +int pci_try_reset_function(struct pci_dev *dev, u32 reset_type);
>  int pci_probe_reset_slot(struct pci_slot *slot);
>  int pci_probe_reset_bus(struct pci_bus *bus);
>  int pci_reset_bus(struct pci_dev *dev);