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
5 * Virtio PCI driver - APIs for common functionality for all device versions
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.
10 * Copyright IBM Corp. 2007
11 * Copyright Red Hat, Inc. 2014
14 * Anthony Liguori <aliguori@us.ibm.com>
15 * Rusty Russell <rusty@rustcorp.com.au>
16 * Michael S. Tsirkin <mst@redhat.com>
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>
34 struct virtio_pci_vq_info
{
35 /* the actual virtqueue */
38 /* the list node for the virtqueues list */
39 struct list_head node
;
41 /* MSI-X vector (or none) */
42 unsigned int msix_vector
;
45 struct virtio_pci_admin_vq
{
46 /* Virtqueue info associated with this admin queue. */
47 struct virtio_pci_vq_info info
;
48 /* serializing admin commands execution and virtqueue deletion */
49 struct mutex cmd_lock
;
51 /* Name of the admin queue: avq.$vq_index. */
56 /* Our device structure */
57 struct virtio_pci_device
{
58 struct virtio_device vdev
;
59 struct pci_dev
*pci_dev
;
61 struct virtio_pci_legacy_device ldev
;
62 struct virtio_pci_modern_device mdev
;
66 /* Where to read and clear interrupt */
69 /* a list of queues so we can dispatch IRQs */
71 struct list_head virtqueues
;
73 /* Array of all virtqueues reported in the
74 * PCI common config num_queues field
76 struct virtio_pci_vq_info
**vqs
;
78 struct virtio_pci_admin_vq admin_vq
;
83 cpumask_var_t
*msix_affinity_masks
;
84 /* Name strings for interrupts. This size should be enough,
85 * and I'm too lazy to allocate each name separately. */
86 char (*msix_names
)[256];
87 /* Number of available vectors */
88 unsigned int msix_vectors
;
89 /* Vectors allocated, excluding per-vq vectors if any */
90 unsigned int msix_used_vectors
;
92 /* Whether we have vector per vq */
95 struct virtqueue
*(*setup_vq
)(struct virtio_pci_device
*vp_dev
,
96 struct virtio_pci_vq_info
*info
,
98 void (*callback
)(struct virtqueue
*vq
),
102 void (*del_vq
)(struct virtio_pci_vq_info
*info
);
104 u16 (*config_vector
)(struct virtio_pci_device
*vp_dev
, u16 vector
);
105 bool (*is_avq
)(struct virtio_device
*vdev
, unsigned int index
);
108 /* Constants for MSI-X */
109 /* Use first vector for configuration changes, second and the rest for
110 * virtqueues Thus, we need at least 2 vectors for MSI. */
112 VP_MSIX_CONFIG_VECTOR
= 0,
113 VP_MSIX_VQ_VECTOR
= 1,
116 /* Convert a generic virtio device to our structure */
117 static struct virtio_pci_device
*to_vp_device(struct virtio_device
*vdev
)
119 return container_of(vdev
, struct virtio_pci_device
, vdev
);
122 /* wait for pending irq handlers */
123 void vp_synchronize_vectors(struct virtio_device
*vdev
);
124 /* the notify function used when creating a virt queue */
125 bool vp_notify(struct virtqueue
*vq
);
126 /* the config->del_vqs() implementation */
127 void vp_del_vqs(struct virtio_device
*vdev
);
128 /* the config->find_vqs() implementation */
129 int vp_find_vqs(struct virtio_device
*vdev
, unsigned int nvqs
,
130 struct virtqueue
*vqs
[], vq_callback_t
*callbacks
[],
131 const char * const names
[], const bool *ctx
,
132 struct irq_affinity
*desc
);
133 const char *vp_bus_name(struct virtio_device
*vdev
);
135 /* Setup the affinity for a virtqueue:
136 * - force the affinity for per vq vector
137 * - OR over all affinities for shared MSI
138 * - ignore the affinity request if we're using INTX
140 int vp_set_vq_affinity(struct virtqueue
*vq
, const struct cpumask
*cpu_mask
);
142 const struct cpumask
*vp_get_vq_affinity(struct virtio_device
*vdev
, int index
);
144 #if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
145 int virtio_pci_legacy_probe(struct virtio_pci_device
*);
146 void virtio_pci_legacy_remove(struct virtio_pci_device
*);
148 static inline int virtio_pci_legacy_probe(struct virtio_pci_device
*vp_dev
)
152 static inline void virtio_pci_legacy_remove(struct virtio_pci_device
*vp_dev
)
156 int virtio_pci_modern_probe(struct virtio_pci_device
*);
157 void virtio_pci_modern_remove(struct virtio_pci_device
*);
159 struct virtio_device
*virtio_pci_vf_get_pf_dev(struct pci_dev
*pdev
);
161 #define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \
162 (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \
163 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \
164 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \
165 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \
166 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO))
168 /* Unlike modern drivers which support hardware virtio devices, legacy drivers
169 * assume software-based devices: e.g. they don't use proper memory barriers
170 * on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more
171 * or less by chance. For now, only support legacy IO on X86.
173 #ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY
174 #define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_LEGACY_ADMIN_CMD_BITMAP
176 #define VIRTIO_ADMIN_CMD_BITMAP 0
179 int vp_modern_admin_cmd_exec(struct virtio_device
*vdev
,
180 struct virtio_admin_cmd
*cmd
);