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 * $FreeBSD$ 29 */ 30 31 #ifndef _VIRTIO_H_ 32 #define _VIRTIO_H_ 33 34 struct 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 * Maximum number of virtqueues per device. 75 */ 76 #define VIRTIO_MAX_VIRTQUEUES 8 77 78 /* 79 * Each virtqueue indirect descriptor list must be physically contiguous. 80 * To allow us to malloc(9) each list individually, limit the number 81 * supported to what will fit in one page. With 4KB pages, this is a limit 82 * of 256 descriptors. If there is ever a need for more, we can switch to 83 * contigmalloc(9) for the larger allocations, similar to what 84 * bus_dmamem_alloc(9) does. 85 * 86 * Note the sizeof(struct vring_desc) is 16 bytes. 87 */ 88 #define VIRTIO_MAX_INDIRECT ((int) (PAGE_SIZE / 16)) 89 90 /* 91 * VirtIO instance variables indices. 92 */ 93 #define VIRTIO_IVAR_DEVTYPE 1 94 #define VIRTIO_IVAR_FEATURE_DESC 2 95 #define VIRTIO_IVAR_VENDOR 3 96 #define VIRTIO_IVAR_DEVICE 4 97 #define VIRTIO_IVAR_SUBVENDOR 5 98 #define VIRTIO_IVAR_SUBDEVICE 6 99 100 struct virtio_feature_desc { 101 uint64_t vfd_val; 102 char *vfd_str; 103 }; 104 105 const char *virtio_device_name(uint16_t devid); 106 void virtio_describe(device_t dev, const char *msg, 107 uint64_t features, struct virtio_feature_desc *feature_desc); 108 109 /* 110 * VirtIO Bus Methods. 111 */ 112 void virtio_read_ivar(device_t dev, int ivar, uintptr_t *val); 113 void virtio_write_ivar(device_t dev, int ivar, uintptr_t val); 114 uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features); 115 int virtio_alloc_virtqueues(device_t dev, int flags, int nvqs, 116 struct vq_alloc_info *info); 117 int virtio_setup_intr(device_t dev, enum intr_type type); 118 int virtio_with_feature(device_t dev, uint64_t feature); 119 void virtio_stop(device_t dev); 120 int virtio_reinit(device_t dev, uint64_t features); 121 void virtio_reinit_complete(device_t dev); 122 123 /* 124 * Read/write a variable amount from the device specific (ie, network) 125 * configuration region. This region is encoded in the same endian as 126 * the guest. 127 */ 128 void virtio_read_device_config(device_t dev, bus_size_t offset, 129 void *dst, int length); 130 void virtio_write_device_config(device_t dev, bus_size_t offset, 131 void *src, int length); 132 133 /* Inlined device specific read/write functions for common lengths. */ 134 #define VIRTIO_RDWR_DEVICE_CONFIG(size, type) \ 135 static inline type \ 136 __CONCAT(virtio_read_dev_config_,size)(device_t dev, \ 137 bus_size_t offset) \ 138 { \ 139 type val; \ 140 virtio_read_device_config(dev, offset, &val, sizeof(type)); \ 141 return (val); \ 142 } \ 143 \ 144 static inline void \ 145 __CONCAT(virtio_write_dev_config_,size)(device_t dev, \ 146 bus_size_t offset, type val) \ 147 { \ 148 virtio_write_device_config(dev, offset, &val, sizeof(type)); \ 149 } 150 151 VIRTIO_RDWR_DEVICE_CONFIG(1, uint8_t); 152 VIRTIO_RDWR_DEVICE_CONFIG(2, uint16_t); 153 VIRTIO_RDWR_DEVICE_CONFIG(4, uint32_t); 154 155 #undef VIRTIO_RDWR_DEVICE_CONFIG 156 157 #define VIRTIO_READ_IVAR(name, ivar) \ 158 static inline int \ 159 __CONCAT(virtio_get_,name)(device_t dev) \ 160 { \ 161 uintptr_t val; \ 162 virtio_read_ivar(dev, ivar, &val); \ 163 return ((int) val); \ 164 } 165 166 VIRTIO_READ_IVAR(device_type, VIRTIO_IVAR_DEVTYPE); 167 VIRTIO_READ_IVAR(vendor, VIRTIO_IVAR_VENDOR); 168 VIRTIO_READ_IVAR(device, VIRTIO_IVAR_DEVICE); 169 VIRTIO_READ_IVAR(subvendor, VIRTIO_IVAR_SUBVENDOR); 170 VIRTIO_READ_IVAR(subdevice, VIRTIO_IVAR_SUBDEVICE); 171 172 #undef VIRTIO_READ_IVAR 173 174 #define VIRTIO_WRITE_IVAR(name, ivar) \ 175 static inline void \ 176 __CONCAT(virtio_set_,name)(device_t dev, void *val) \ 177 { \ 178 virtio_write_ivar(dev, ivar, (uintptr_t) val); \ 179 } 180 181 VIRTIO_WRITE_IVAR(feature_desc, VIRTIO_IVAR_FEATURE_DESC); 182 183 #undef VIRTIO_WRITE_IVAR 184 185 #endif /* _VIRTIO_H_ */ 186