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/* 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>
#include <linux/mutex.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;
};
struct virtio_pci_admin_vq {
/* Virtqueue info associated with this admin queue. */
struct virtio_pci_vq_info info;
/* serializing admin commands execution and virtqueue deletion */
struct mutex cmd_lock;
u64 supported_cmds;
/* Name of the admin queue: avq.$vq_index. */
char name[10];
u16 vq_index;
};
/* 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 virtqueues reported in the
* PCI common config num_queues field
*/
struct virtio_pci_vq_info **vqs;
struct virtio_pci_admin_vq admin_vq;
/* 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);
bool (*is_avq)(struct virtio_device *vdev, unsigned int index);
};
/* 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 *);
#define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \
(BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \
BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \
BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \
BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \
BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO))
/* Unlike modern drivers which support hardware virtio devices, legacy drivers
* assume software-based devices: e.g. they don't use proper memory barriers
* on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more
* or less by chance. For now, only support legacy IO on X86.
*/
#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY
#define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_LEGACY_ADMIN_CMD_BITMAP
#else
#define VIRTIO_ADMIN_CMD_BITMAP 0
#endif
int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
struct virtio_admin_cmd *cmd);
#endif
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