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