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1#ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H
2#define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H
3/*
4 * Virtio PCI driver - APIs for common functionality for all device versions
5 *
6 * This module allows virtio devices to be used over a virtual PCI device.
7 * This can be used with QEMU based VMMs like KVM or Xen.
8 *
9 * Copyright IBM Corp. 2007
10 * Copyright Red Hat, Inc. 2014
11 *
12 * Authors:
13 * Anthony Liguori <aliguori@us.ibm.com>
14 * Rusty Russell <rusty@rustcorp.com.au>
15 * Michael S. Tsirkin <mst@redhat.com>
16 *
17 * This work is licensed under the terms of the GNU GPL, version 2 or later.
18 * See the COPYING file in the top-level directory.
19 *
20 */
21
22#include <linux/module.h>
23#include <linux/list.h>
24#include <linux/pci.h>
25#include <linux/slab.h>
26#include <linux/interrupt.h>
27#include <linux/virtio.h>
28#include <linux/virtio_config.h>
29#include <linux/virtio_ring.h>
30#include <linux/virtio_pci.h>
31#include <linux/highmem.h>
32#include <linux/spinlock.h>
33
34struct virtio_pci_vq_info {
35 /* the actual virtqueue */
36 struct virtqueue *vq;
37
38 /* the list node for the virtqueues list */
39 struct list_head node;
40
41 /* MSI-X vector (or none) */
42 unsigned msix_vector;
43};
44
45/* Our device structure */
46struct virtio_pci_device {
47 struct virtio_device vdev;
48 struct pci_dev *pci_dev;
49
50 /* In legacy mode, these two point to within ->legacy. */
51 /* Where to read and clear interrupt */
52 u8 __iomem *isr;
53
54 /* Modern only fields */
55 /* The IO mapping for the PCI config space (non-legacy mode) */
56 struct virtio_pci_common_cfg __iomem *common;
57 /* Device-specific data (non-legacy mode) */
58 void __iomem *device;
59 /* Base of vq notifications (non-legacy mode). */
60 void __iomem *notify_base;
61
62 /* So we can sanity-check accesses. */
63 size_t notify_len;
64 size_t device_len;
65
66 /* Capability for when we need to map notifications per-vq. */
67 int notify_map_cap;
68
69 /* Multiply queue_notify_off by this value. (non-legacy mode). */
70 u32 notify_offset_multiplier;
71
72 int modern_bars;
73
74 /* Legacy only field */
75 /* the IO mapping for the PCI config space */
76 void __iomem *ioaddr;
77
78 /* a list of queues so we can dispatch IRQs */
79 spinlock_t lock;
80 struct list_head virtqueues;
81
82 /* array of all queues for house-keeping */
83 struct virtio_pci_vq_info **vqs;
84
85 /* MSI-X support */
86 int msix_enabled;
87 int intx_enabled;
88 cpumask_var_t *msix_affinity_masks;
89 /* Name strings for interrupts. This size should be enough,
90 * and I'm too lazy to allocate each name separately. */
91 char (*msix_names)[256];
92 /* Number of available vectors */
93 unsigned msix_vectors;
94 /* Vectors allocated, excluding per-vq vectors if any */
95 unsigned msix_used_vectors;
96
97 /* Whether we have vector per vq */
98 bool per_vq_vectors;
99
100 struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev,
101 struct virtio_pci_vq_info *info,
102 unsigned idx,
103 void (*callback)(struct virtqueue *vq),
104 const char *name,
105 bool ctx,
106 u16 msix_vec);
107 void (*del_vq)(struct virtio_pci_vq_info *info);
108
109 u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector);
110};
111
112/* Constants for MSI-X */
113/* Use first vector for configuration changes, second and the rest for
114 * virtqueues Thus, we need at least 2 vectors for MSI. */
115enum {
116 VP_MSIX_CONFIG_VECTOR = 0,
117 VP_MSIX_VQ_VECTOR = 1,
118};
119
120/* Convert a generic virtio device to our structure */
121static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
122{
123 return container_of(vdev, struct virtio_pci_device, vdev);
124}
125
126/* wait for pending irq handlers */
127void vp_synchronize_vectors(struct virtio_device *vdev);
128/* the notify function used when creating a virt queue */
129bool vp_notify(struct virtqueue *vq);
130/* the config->del_vqs() implementation */
131void vp_del_vqs(struct virtio_device *vdev);
132/* the config->find_vqs() implementation */
133int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
134 struct virtqueue *vqs[], vq_callback_t *callbacks[],
135 const char * const names[], const bool *ctx,
136 struct irq_affinity *desc);
137const char *vp_bus_name(struct virtio_device *vdev);
138
139/* Setup the affinity for a virtqueue:
140 * - force the affinity for per vq vector
141 * - OR over all affinities for shared MSI
142 * - ignore the affinity request if we're using INTX
143 */
144int vp_set_vq_affinity(struct virtqueue *vq, int cpu);
145
146const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index);
147
148#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
149int virtio_pci_legacy_probe(struct virtio_pci_device *);
150void virtio_pci_legacy_remove(struct virtio_pci_device *);
151#else
152static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
153{
154 return -ENODEV;
155}
156static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev)
157{
158}
159#endif
160int virtio_pci_modern_probe(struct virtio_pci_device *);
161void virtio_pci_modern_remove(struct virtio_pci_device *);
162
163#endif