/* 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