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 34 struct 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 */ 46 struct 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 struct msix_entry *msix_entries; 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 msix_vectors; 95 /* Vectors allocated, excluding per-vq vectors if any */ 96 unsigned 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 idx, 104 void (*callback)(struct virtqueue *vq), 105 const char *name, 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. */ 115 enum { 116 VP_MSIX_CONFIG_VECTOR = 0, 117 VP_MSIX_VQ_VECTOR = 1, 118 }; 119 120 /* Convert a generic virtio device to our structure */ 121 static 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 */ 127 void vp_synchronize_vectors(struct virtio_device *vdev); 128 /* the notify function used when creating a virt queue */ 129 bool vp_notify(struct virtqueue *vq); 130 /* the config->del_vqs() implementation */ 131 void vp_del_vqs(struct virtio_device *vdev); 132 /* the config->find_vqs() implementation */ 133 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, 134 struct virtqueue *vqs[], 135 vq_callback_t *callbacks[], 136 const char * const names[]); 137 const 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 */ 144 int vp_set_vq_affinity(struct virtqueue *vq, int cpu); 145 146 #if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY) 147 int virtio_pci_legacy_probe(struct virtio_pci_device *); 148 void virtio_pci_legacy_remove(struct virtio_pci_device *); 149 #else 150 static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) 151 { 152 return -ENODEV; 153 } 154 static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) 155 { 156 } 157 #endif 158 int virtio_pci_modern_probe(struct virtio_pci_device *); 159 void virtio_pci_modern_remove(struct virtio_pci_device *); 160 161 #endif 162