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#include <linux/mutex.h>
33
34struct virtio_pci_vq_info {
35 /* the actual virtqueue */
36 struct virtqueue *vq;
37
38 /* the list node for the virtqueues or slow_virtqueues list */
39 struct list_head node;
40
41 /* MSI-X vector (or none) */
42 unsigned int msix_vector;
43};
44
45struct virtio_pci_admin_vq {
46 /* Virtqueue info associated with this admin queue. */
47 struct virtio_pci_vq_info *info;
48 /* Protects virtqueue access. */
49 spinlock_t lock;
50 u64 supported_cmds;
51 u64 supported_caps;
52 u8 max_dev_parts_objects;
53 struct ida dev_parts_ida;
54 /* Name of the admin queue: avq.$vq_index. */
55 char name[10];
56 u16 vq_index;
57};
58
59/* Our device structure */
60struct virtio_pci_device {
61 struct virtio_device vdev;
62 struct pci_dev *pci_dev;
63 union {
64 struct virtio_pci_legacy_device ldev;
65 struct virtio_pci_modern_device mdev;
66 };
67 bool is_legacy;
68
69 /* Where to read and clear interrupt */
70 u8 __iomem *isr;
71
72 /* Lists of queues and potentially slow path queues
73 * so we can dispatch IRQs.
74 */
75 spinlock_t lock;
76 struct list_head virtqueues;
77 struct list_head slow_virtqueues;
78
79 /* Array of all virtqueues reported in the
80 * PCI common config num_queues field
81 */
82 struct virtio_pci_vq_info **vqs;
83
84 struct virtio_pci_admin_vq admin_vq;
85
86 /* MSI-X support */
87 int msix_enabled;
88 int intx_enabled;
89 cpumask_var_t *msix_affinity_masks;
90 /* Name strings for interrupts. This size should be enough,
91 * and I'm too lazy to allocate each name separately. */
92 char (*msix_names)[256];
93 /* Number of available vectors */
94 unsigned int msix_vectors;
95 /* Vectors allocated, excluding per-vq vectors if any */
96 unsigned int msix_used_vectors;
97
98 /* Whether we have vector per vq */
99 bool per_vq_vectors;
100
101 struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev,
102 struct virtio_pci_vq_info *info,
103 unsigned int idx,
104 void (*callback)(struct virtqueue *vq),
105 const char *name,
106 bool ctx,
107 u16 msix_vec);
108 void (*del_vq)(struct virtio_pci_vq_info *info);
109
110 u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector);
111 int (*avq_index)(struct virtio_device *vdev, u16 *index, u16 *num);
112};
113
114/* Constants for MSI-X */
115/* Use first vector for configuration changes, second and the rest for
116 * virtqueues Thus, we need at least 2 vectors for MSI. */
117enum {
118 VP_MSIX_CONFIG_VECTOR = 0,
119 VP_MSIX_VQ_VECTOR = 1,
120};
121
122/* Convert a generic virtio device to our structure */
123static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
124{
125 return container_of(vdev, struct virtio_pci_device, vdev);
126}
127
128/* wait for pending irq handlers */
129void vp_synchronize_vectors(struct virtio_device *vdev);
130/* the notify function used when creating a virt queue */
131bool vp_notify(struct virtqueue *vq);
132/* the config->del_vqs() implementation */
133void vp_del_vqs(struct virtio_device *vdev);
134/* the config->find_vqs() implementation */
135int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
136 struct virtqueue *vqs[], struct virtqueue_info vqs_info[],
137 struct irq_affinity *desc);
138const char *vp_bus_name(struct virtio_device *vdev);
139
140/* Setup the affinity for a virtqueue:
141 * - force the affinity for per vq vector
142 * - OR over all affinities for shared MSI
143 * - ignore the affinity request if we're using INTX
144 */
145int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask);
146
147const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index);
148
149#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
150int virtio_pci_legacy_probe(struct virtio_pci_device *);
151void virtio_pci_legacy_remove(struct virtio_pci_device *);
152#else
153static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)
154{
155 return -ENODEV;
156}
157static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev)
158{
159}
160#endif
161int virtio_pci_modern_probe(struct virtio_pci_device *);
162void virtio_pci_modern_remove(struct virtio_pci_device *);
163
164struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev);
165
166#define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \
167 (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \
168 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \
169 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \
170 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \
171 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO))
172
173#define VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP \
174 (BIT_ULL(VIRTIO_ADMIN_CMD_CAP_ID_LIST_QUERY) | \
175 BIT_ULL(VIRTIO_ADMIN_CMD_DRIVER_CAP_SET) | \
176 BIT_ULL(VIRTIO_ADMIN_CMD_DEVICE_CAP_GET) | \
177 BIT_ULL(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_CREATE) | \
178 BIT_ULL(VIRTIO_ADMIN_CMD_RESOURCE_OBJ_DESTROY) | \
179 BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_METADATA_GET) | \
180 BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_GET) | \
181 BIT_ULL(VIRTIO_ADMIN_CMD_DEV_PARTS_SET) | \
182 BIT_ULL(VIRTIO_ADMIN_CMD_DEV_MODE_SET))
183
184/* Unlike modern drivers which support hardware virtio devices, legacy drivers
185 * assume software-based devices: e.g. they don't use proper memory barriers
186 * on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more
187 * or less by chance. For now, only support legacy IO on X86.
188 */
189#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY
190#define VIRTIO_ADMIN_CMD_BITMAP (VIRTIO_LEGACY_ADMIN_CMD_BITMAP | \
191 VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP)
192#else
193#define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_DEV_PARTS_ADMIN_CMD_BITMAP
194#endif
195
196bool vp_is_avq(struct virtio_device *vdev, unsigned int index);
197void vp_modern_avq_done(struct virtqueue *vq);
198int vp_modern_admin_cmd_exec(struct virtio_device *vdev,
199 struct virtio_admin_cmd *cmd);
200
201#endif
202

source code of linux/drivers/virtio/virtio_pci_common.h