Commit 9e3bb9b7 authored by Jason Wang's avatar Jason Wang Committed by Michael S. Tsirkin
Browse files

virtio_pci_modern: introduce helper to map vq notify area 



This patch factors out the logic of vq notify area mapping. Following
patches will switch to use this common helpers for both virtio_pci
library and virtio-pci vDPA driver.

Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210415073147.19331-2-jasowang@redhat.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarEli Cohen <elic@nvidia.com>
parent 122b84a1

drivers/virtio/virtio_pci_modern_dev.c

+35 −0
Original line number Diff line number Diff line
@@ -593,6 +593,41 @@ u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev, 
}

EXPORT_SYMBOL_GPL(vp_modern_get_queue_notify_off);



/*

 * vp_modern_map_vq_notify - map notification area for a

 * specific virtqueue

 * @mdev: the modern virtio-pci device

 * @index: the queue index

 *

 * Returns the address of the notification area

 */

void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,

			      u16 index)

{

	u16 off = vp_modern_get_queue_notify_off(mdev, index);



	if (mdev->notify_base) {

		/* offset should not wrap */

		if ((u64)off * mdev->notify_offset_multiplier + 2

			> mdev->notify_len) {

			dev_warn(&mdev->pci_dev->dev,

				 "bad notification offset %u (x %u) "

				 "for queue %u > %zd",

				 off, mdev->notify_offset_multiplier,

				 index, mdev->notify_len);

			return NULL;

		}

		return (void __force *)mdev->notify_base +

			off * mdev->notify_offset_multiplier;

	} else {

		return (void __force *)vp_modern_map_capability(mdev,

				       mdev->notify_map_cap, 2, 2,

				       off * mdev->notify_offset_multiplier, 2,

				       NULL);

	}

}

EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);



MODULE_VERSION("0.1");

MODULE_DESCRIPTION("Modern Virtio PCI Device");

MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");

include/linux/virtio_pci_modern.h

+2 −0
Original line number Diff line number Diff line
@@ -106,6 +106,8 @@ void __iomem *vp_modern_map_capability(struct virtio_pci_modern_device *mdev, in 
				       u32 align,

				       u32 start, u32 size,

				       size_t *len);

void *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,

                              u16 index);

int vp_modern_probe(struct virtio_pci_modern_device *mdev);

void vp_modern_remove(struct virtio_pci_modern_device *mdev);

#endif