diff options
Diffstat (limited to 'drivers/virtio/virtio_pci_common.h')
| -rw-r--r-- | drivers/virtio/virtio_pci_common.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_pci_common.h b/drivers/virtio/virtio_pci_common.h new file mode 100644 index 000000000..4b773bd7c --- /dev/null +++ b/drivers/virtio/virtio_pci_common.h @@ -0,0 +1,142 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H +#define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H +/* + * Virtio PCI driver - APIs for common functionality for all device versions + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * Copyright Red Hat, Inc. 2014 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * Rusty Russell <rusty@rustcorp.com.au> + * Michael S. Tsirkin <mst@redhat.com> + */ + +#include <linux/module.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ring.h> +#include <linux/virtio_pci.h> +#include <linux/virtio_pci_legacy.h> +#include <linux/virtio_pci_modern.h> +#include <linux/highmem.h> +#include <linux/spinlock.h> + +struct virtio_pci_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the list node for the virtqueues list */ + struct list_head node; + + /* MSI-X vector (or none) */ + unsigned int msix_vector; +}; + +/* Our device structure */ +struct virtio_pci_device { + struct virtio_device vdev; + struct pci_dev *pci_dev; + union { + struct virtio_pci_legacy_device ldev; + struct virtio_pci_modern_device mdev; + }; + bool is_legacy; + + /* Where to read and clear interrupt */ + u8 __iomem *isr; + + /* a list of queues so we can dispatch IRQs */ + spinlock_t lock; + struct list_head virtqueues; + + /* array of all queues for house-keeping */ + struct virtio_pci_vq_info **vqs; + + /* MSI-X support */ + int msix_enabled; + int intx_enabled; + cpumask_var_t *msix_affinity_masks; + /* Name strings for interrupts. This size should be enough, + * and I'm too lazy to allocate each name separately. */ + char (*msix_names)[256]; + /* Number of available vectors */ + unsigned int msix_vectors; + /* Vectors allocated, excluding per-vq vectors if any */ + unsigned int msix_used_vectors; + + /* Whether we have vector per vq */ + bool per_vq_vectors; + + struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev, + struct virtio_pci_vq_info *info, + unsigned int idx, + void (*callback)(struct virtqueue *vq), + const char *name, + bool ctx, + u16 msix_vec); + void (*del_vq)(struct virtio_pci_vq_info *info); + + u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector); +}; + +/* Constants for MSI-X */ +/* Use first vector for configuration changes, second and the rest for + * virtqueues Thus, we need at least 2 vectors for MSI. */ +enum { + VP_MSIX_CONFIG_VECTOR = 0, + VP_MSIX_VQ_VECTOR = 1, +}; + +/* Convert a generic virtio device to our structure */ +static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) +{ + return container_of(vdev, struct virtio_pci_device, vdev); +} + +/* wait for pending irq handlers */ +void vp_synchronize_vectors(struct virtio_device *vdev); +/* the notify function used when creating a virt queue */ +bool vp_notify(struct virtqueue *vq); +/* the config->del_vqs() implementation */ +void vp_del_vqs(struct virtio_device *vdev); +/* the config->find_vqs() implementation */ +int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs, + struct virtqueue *vqs[], vq_callback_t *callbacks[], + const char * const names[], const bool *ctx, + struct irq_affinity *desc); +const char *vp_bus_name(struct virtio_device *vdev); + +/* Setup the affinity for a virtqueue: + * - force the affinity for per vq vector + * - OR over all affinities for shared MSI + * - ignore the affinity request if we're using INTX + */ +int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask); + +const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index); + +#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY) +int virtio_pci_legacy_probe(struct virtio_pci_device *); +void virtio_pci_legacy_remove(struct virtio_pci_device *); +#else +static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) +{ + return -ENODEV; +} +static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) +{ +} +#endif +int virtio_pci_modern_probe(struct virtio_pci_device *); +void virtio_pci_modern_remove(struct virtio_pci_device *); + +#endif |