1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | #ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H |
3 | #define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H |
4 | /* |
5 | * Virtio PCI driver - APIs for common functionality for all device versions |
6 | * |
7 | * This module allows virtio devices to be used over a virtual PCI device. |
8 | * This can be used with QEMU based VMMs like KVM or Xen. |
9 | * |
10 | * Copyright IBM Corp. 2007 |
11 | * Copyright Red Hat, Inc. 2014 |
12 | * |
13 | * Authors: |
14 | * Anthony Liguori <aliguori@us.ibm.com> |
15 | * Rusty Russell <rusty@rustcorp.com.au> |
16 | * Michael S. Tsirkin <mst@redhat.com> |
17 | */ |
18 | |
19 | #include <linux/module.h> |
20 | #include <linux/list.h> |
21 | #include <linux/pci.h> |
22 | #include <linux/slab.h> |
23 | #include <linux/interrupt.h> |
24 | #include <linux/virtio.h> |
25 | #include <linux/virtio_config.h> |
26 | #include <linux/virtio_ring.h> |
27 | #include <linux/virtio_pci.h> |
28 | #include <linux/virtio_pci_legacy.h> |
29 | #include <linux/virtio_pci_modern.h> |
30 | #include <linux/highmem.h> |
31 | #include <linux/spinlock.h> |
32 | |
33 | struct virtio_pci_vq_info { |
34 | /* the actual virtqueue */ |
35 | struct virtqueue *vq; |
36 | |
37 | /* the list node for the virtqueues list */ |
38 | struct list_head node; |
39 | |
40 | /* MSI-X vector (or none) */ |
41 | unsigned int msix_vector; |
42 | }; |
43 | |
44 | /* Our device structure */ |
45 | struct virtio_pci_device { |
46 | struct virtio_device vdev; |
47 | struct pci_dev *pci_dev; |
48 | union { |
49 | struct virtio_pci_legacy_device ldev; |
50 | struct virtio_pci_modern_device mdev; |
51 | }; |
52 | bool is_legacy; |
53 | |
54 | /* Where to read and clear interrupt */ |
55 | u8 __iomem *isr; |
56 | |
57 | /* a list of queues so we can dispatch IRQs */ |
58 | spinlock_t lock; |
59 | struct list_head virtqueues; |
60 | |
61 | /* array of all queues for house-keeping */ |
62 | struct virtio_pci_vq_info **vqs; |
63 | |
64 | /* MSI-X support */ |
65 | int msix_enabled; |
66 | int intx_enabled; |
67 | cpumask_var_t *msix_affinity_masks; |
68 | /* Name strings for interrupts. This size should be enough, |
69 | * and I'm too lazy to allocate each name separately. */ |
70 | char (*msix_names)[256]; |
71 | /* Number of available vectors */ |
72 | unsigned int msix_vectors; |
73 | /* Vectors allocated, excluding per-vq vectors if any */ |
74 | unsigned int msix_used_vectors; |
75 | |
76 | /* Whether we have vector per vq */ |
77 | bool per_vq_vectors; |
78 | |
79 | struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev, |
80 | struct virtio_pci_vq_info *info, |
81 | unsigned int idx, |
82 | void (*callback)(struct virtqueue *vq), |
83 | const char *name, |
84 | bool ctx, |
85 | u16 msix_vec); |
86 | void (*del_vq)(struct virtio_pci_vq_info *info); |
87 | |
88 | u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector); |
89 | }; |
90 | |
91 | /* Constants for MSI-X */ |
92 | /* Use first vector for configuration changes, second and the rest for |
93 | * virtqueues Thus, we need at least 2 vectors for MSI. */ |
94 | enum { |
95 | VP_MSIX_CONFIG_VECTOR = 0, |
96 | VP_MSIX_VQ_VECTOR = 1, |
97 | }; |
98 | |
99 | /* Convert a generic virtio device to our structure */ |
100 | static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) |
101 | { |
102 | return container_of(vdev, struct virtio_pci_device, vdev); |
103 | } |
104 | |
105 | /* wait for pending irq handlers */ |
106 | void vp_synchronize_vectors(struct virtio_device *vdev); |
107 | /* the notify function used when creating a virt queue */ |
108 | bool vp_notify(struct virtqueue *vq); |
109 | /* the config->del_vqs() implementation */ |
110 | void vp_del_vqs(struct virtio_device *vdev); |
111 | /* the config->find_vqs() implementation */ |
112 | int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs, |
113 | struct virtqueue *vqs[], vq_callback_t *callbacks[], |
114 | const char * const names[], const bool *ctx, |
115 | struct irq_affinity *desc); |
116 | const char *vp_bus_name(struct virtio_device *vdev); |
117 | |
118 | /* Setup the affinity for a virtqueue: |
119 | * - force the affinity for per vq vector |
120 | * - OR over all affinities for shared MSI |
121 | * - ignore the affinity request if we're using INTX |
122 | */ |
123 | int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask); |
124 | |
125 | const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index); |
126 | |
127 | #if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY) |
128 | int virtio_pci_legacy_probe(struct virtio_pci_device *); |
129 | void virtio_pci_legacy_remove(struct virtio_pci_device *); |
130 | #else |
131 | static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) |
132 | { |
133 | return -ENODEV; |
134 | } |
135 | static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) |
136 | { |
137 | } |
138 | #endif |
139 | int virtio_pci_modern_probe(struct virtio_pci_device *); |
140 | void virtio_pci_modern_remove(struct virtio_pci_device *); |
141 | |
142 | #endif |
143 | |