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 number of entries in the queue */ 39 int num; 40 41 /* the virtual address of the ring queue */ 42 void *queue; 43 44 /* the list node for the virtqueues list */ 45 struct list_head node; 46 47 /* MSI-X vector (or none) */ 48 unsigned msix_vector; 49 }; 50 51 /* Our device structure */ 52 struct virtio_pci_device { 53 struct virtio_device vdev; 54 struct pci_dev *pci_dev; 55 56 /* the IO mapping for the PCI config space */ 57 void __iomem *ioaddr; 58 59 /* the IO mapping for ISR operation */ 60 void __iomem *isr; 61 62 /* a list of queues so we can dispatch IRQs */ 63 spinlock_t lock; 64 struct list_head virtqueues; 65 66 /* array of all queues for house-keeping */ 67 struct virtio_pci_vq_info **vqs; 68 69 /* MSI-X support */ 70 int msix_enabled; 71 int intx_enabled; 72 struct msix_entry *msix_entries; 73 cpumask_var_t *msix_affinity_masks; 74 /* Name strings for interrupts. This size should be enough, 75 * and I'm too lazy to allocate each name separately. */ 76 char (*msix_names)[256]; 77 /* Number of available vectors */ 78 unsigned msix_vectors; 79 /* Vectors allocated, excluding per-vq vectors if any */ 80 unsigned msix_used_vectors; 81 82 /* Whether we have vector per vq */ 83 bool per_vq_vectors; 84 85 struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev, 86 struct virtio_pci_vq_info *info, 87 unsigned idx, 88 void (*callback)(struct virtqueue *vq), 89 const char *name, 90 u16 msix_vec); 91 void (*del_vq)(struct virtio_pci_vq_info *info); 92 93 u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector); 94 }; 95 96 /* Constants for MSI-X */ 97 /* Use first vector for configuration changes, second and the rest for 98 * virtqueues Thus, we need at least 2 vectors for MSI. */ 99 enum { 100 VP_MSIX_CONFIG_VECTOR = 0, 101 VP_MSIX_VQ_VECTOR = 1, 102 }; 103 104 /* Convert a generic virtio device to our structure */ 105 static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) 106 { 107 return container_of(vdev, struct virtio_pci_device, vdev); 108 } 109 110 /* wait for pending irq handlers */ 111 void vp_synchronize_vectors(struct virtio_device *vdev); 112 /* the notify function used when creating a virt queue */ 113 bool vp_notify(struct virtqueue *vq); 114 /* the config->del_vqs() implementation */ 115 void vp_del_vqs(struct virtio_device *vdev); 116 /* the config->find_vqs() implementation */ 117 int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, 118 struct virtqueue *vqs[], 119 vq_callback_t *callbacks[], 120 const char *names[]); 121 const char *vp_bus_name(struct virtio_device *vdev); 122 123 /* Setup the affinity for a virtqueue: 124 * - force the affinity for per vq vector 125 * - OR over all affinities for shared MSI 126 * - ignore the affinity request if we're using INTX 127 */ 128 int vp_set_vq_affinity(struct virtqueue *vq, int cpu); 129 130 int virtio_pci_legacy_probe(struct pci_dev *pci_dev, 131 const struct pci_device_id *id); 132 void virtio_pci_legacy_remove(struct pci_dev *pci_dev); 133 134 #endif 135