virtio.h revision 252708
1/*- 2 * This header is BSD licensed so anyone can use the definitions to implement 3 * compatible drivers/servers. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of IBM nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD: head/sys/dev/virtio/virtio.h 252708 2013-07-04 17:59:09Z bryanv $ 29 */ 30 31#ifndef _VIRTIO_H_ 32#define _VIRTIO_H_ 33 34struct vq_alloc_info; 35 36/* VirtIO device IDs. */ 37#define VIRTIO_ID_NETWORK 0x01 38#define VIRTIO_ID_BLOCK 0x02 39#define VIRTIO_ID_CONSOLE 0x03 40#define VIRTIO_ID_ENTROPY 0x04 41#define VIRTIO_ID_BALLOON 0x05 42#define VIRTIO_ID_IOMEMORY 0x06 43#define VIRTIO_ID_SCSI 0x08 44#define VIRTIO_ID_9P 0x09 45 46/* Status byte for guest to report progress. */ 47#define VIRTIO_CONFIG_STATUS_RESET 0x00 48#define VIRTIO_CONFIG_STATUS_ACK 0x01 49#define VIRTIO_CONFIG_STATUS_DRIVER 0x02 50#define VIRTIO_CONFIG_STATUS_DRIVER_OK 0x04 51#define VIRTIO_CONFIG_STATUS_FAILED 0x80 52 53/* 54 * Generate interrupt when the virtqueue ring is 55 * completely used, even if we've suppressed them. 56 */ 57#define VIRTIO_F_NOTIFY_ON_EMPTY (1 << 24) 58 59/* 60 * The guest should never negotiate this feature; it 61 * is used to detect faulty drivers. 62 */ 63#define VIRTIO_F_BAD_FEATURE (1 << 30) 64 65/* 66 * Some VirtIO feature bits (currently bits 28 through 31) are 67 * reserved for the transport being used (eg. virtio_ring), the 68 * rest are per-device feature bits. 69 */ 70#define VIRTIO_TRANSPORT_F_START 28 71#define VIRTIO_TRANSPORT_F_END 32 72 73/* 74 * Each virtqueue indirect descriptor list must be physically contiguous. 75 * To allow us to malloc(9) each list individually, limit the number 76 * supported to what will fit in one page. With 4KB pages, this is a limit 77 * of 256 descriptors. If there is ever a need for more, we can switch to 78 * contigmalloc(9) for the larger allocations, similar to what 79 * bus_dmamem_alloc(9) does. 80 * 81 * Note the sizeof(struct vring_desc) is 16 bytes. 82 */ 83#define VIRTIO_MAX_INDIRECT ((int) (PAGE_SIZE / 16)) 84 85/* 86 * VirtIO instance variables indices. 87 */ 88#define VIRTIO_IVAR_DEVTYPE 1 89#define VIRTIO_IVAR_FEATURE_DESC 2 90#define VIRTIO_IVAR_VENDOR 3 91#define VIRTIO_IVAR_DEVICE 4 92#define VIRTIO_IVAR_SUBVENDOR 5 93#define VIRTIO_IVAR_SUBDEVICE 6 94 95struct virtio_feature_desc { 96 uint64_t vfd_val; 97 const char *vfd_str; 98}; 99 100const char *virtio_device_name(uint16_t devid); 101void virtio_describe(device_t dev, const char *msg, 102 uint64_t features, struct virtio_feature_desc *feature_desc); 103 104/* 105 * VirtIO Bus Methods. 106 */ 107void virtio_read_ivar(device_t dev, int ivar, uintptr_t *val); 108void virtio_write_ivar(device_t dev, int ivar, uintptr_t val); 109uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features); 110int virtio_alloc_virtqueues(device_t dev, int flags, int nvqs, 111 struct vq_alloc_info *info); 112int virtio_setup_intr(device_t dev, enum intr_type type); 113int virtio_with_feature(device_t dev, uint64_t feature); 114void virtio_stop(device_t dev); 115int virtio_reinit(device_t dev, uint64_t features); 116void virtio_reinit_complete(device_t dev); 117 118/* 119 * Read/write a variable amount from the device specific (ie, network) 120 * configuration region. This region is encoded in the same endian as 121 * the guest. 122 */ 123void virtio_read_device_config(device_t dev, bus_size_t offset, 124 void *dst, int length); 125void virtio_write_device_config(device_t dev, bus_size_t offset, 126 void *src, int length); 127 128/* Inlined device specific read/write functions for common lengths. */ 129#define VIRTIO_RDWR_DEVICE_CONFIG(size, type) \ 130static inline type \ 131__CONCAT(virtio_read_dev_config_,size)(device_t dev, \ 132 bus_size_t offset) \ 133{ \ 134 type val; \ 135 virtio_read_device_config(dev, offset, &val, sizeof(type)); \ 136 return (val); \ 137} \ 138 \ 139static inline void \ 140__CONCAT(virtio_write_dev_config_,size)(device_t dev, \ 141 bus_size_t offset, type val) \ 142{ \ 143 virtio_write_device_config(dev, offset, &val, sizeof(type)); \ 144} 145 146VIRTIO_RDWR_DEVICE_CONFIG(1, uint8_t); 147VIRTIO_RDWR_DEVICE_CONFIG(2, uint16_t); 148VIRTIO_RDWR_DEVICE_CONFIG(4, uint32_t); 149 150#undef VIRTIO_RDWR_DEVICE_CONFIG 151 152#define VIRTIO_READ_IVAR(name, ivar) \ 153static inline int \ 154__CONCAT(virtio_get_,name)(device_t dev) \ 155{ \ 156 uintptr_t val; \ 157 virtio_read_ivar(dev, ivar, &val); \ 158 return ((int) val); \ 159} 160 161VIRTIO_READ_IVAR(device_type, VIRTIO_IVAR_DEVTYPE); 162VIRTIO_READ_IVAR(vendor, VIRTIO_IVAR_VENDOR); 163VIRTIO_READ_IVAR(device, VIRTIO_IVAR_DEVICE); 164VIRTIO_READ_IVAR(subvendor, VIRTIO_IVAR_SUBVENDOR); 165VIRTIO_READ_IVAR(subdevice, VIRTIO_IVAR_SUBDEVICE); 166 167#undef VIRTIO_READ_IVAR 168 169#define VIRTIO_WRITE_IVAR(name, ivar) \ 170static inline void \ 171__CONCAT(virtio_set_,name)(device_t dev, void *val) \ 172{ \ 173 virtio_write_ivar(dev, ivar, (uintptr_t) val); \ 174} 175 176VIRTIO_WRITE_IVAR(feature_desc, VIRTIO_IVAR_FEATURE_DESC); 177 178#undef VIRTIO_WRITE_IVAR 179 180#endif /* _VIRTIO_H_ */ 181