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: src/sys/dev/virtio/virtio.h,v 1.2 2011/12/06 06:28:32 grehan Exp $ 29 */ 30 31 #ifndef _VIRTIO_H_ 32 #define _VIRTIO_H_ 33 34 #include <sys/types.h> 35 #include <sys/serialize.h> 36 37 struct vq_alloc_info; 38 39 /* VirtIO device IDs. */ 40 #define VIRTIO_ID_NETWORK 0x01 41 #define VIRTIO_ID_BLOCK 0x02 42 #define VIRTIO_ID_CONSOLE 0x03 43 #define VIRTIO_ID_ENTROPY 0x04 44 #define VIRTIO_ID_BALLOON 0x05 45 #define VIRTIO_ID_IOMEMORY 0x06 46 #define VIRTIO_ID_SCSI 0x08 47 #define VIRTIO_ID_9P 0x09 48 49 /* Status byte for guest to report progress. */ 50 #define VIRTIO_CONFIG_STATUS_RESET 0x00 51 #define VIRTIO_CONFIG_STATUS_ACK 0x01 52 #define VIRTIO_CONFIG_STATUS_DRIVER 0x02 53 #define VIRTIO_CONFIG_STATUS_DRIVER_OK 0x04 54 #define VIRTIO_CONFIG_STATUS_DEVICE_NEEDS_RESET 0x40 55 #define VIRTIO_CONFIG_STATUS_FAILED 0x80 56 57 /* 58 * Generate interrupt when the virtqueue ring is 59 * completely used, even if we've suppressed them. 60 */ 61 #define VIRTIO_F_NOTIFY_ON_EMPTY (1 << 24) 62 63 /* The device accepts arbitrary descriptor layouts */ 64 #define VIRTIO_F_ANY_LAYOUT (1 << 27) 65 66 /* 67 * The guest should never negotiate this feature; it 68 * is used to detect faulty drivers. 69 */ 70 #define VIRTIO_F_BAD_FEATURE (1 << 30) 71 72 /* 73 * Some VirtIO feature bits (currently bits 28 through 31) are 74 * reserved for the transport being used (eg. virtio_ring), the 75 * rest are per-device feature bits. 76 */ 77 #define VIRTIO_TRANSPORT_F_START 28 78 #define VIRTIO_TRANSPORT_F_END 32 79 80 /* 81 * Maximum number of virtqueues per device. 82 */ 83 #define VIRTIO_MAX_VIRTQUEUES 8 84 85 /* 86 * XXX malloc(9) comment not correct on DragonFly 87 * Each virtqueue indirect descriptor list must be physically contiguous. 88 * To allow us to malloc(9) each list individually, limit the number 89 * supported to what will fit in one page. With 4KB pages, this is a limit 90 * of 256 descriptors. If there is ever a need for more, we can switch to 91 * contigmalloc(9) for the larger allocations, similar to what 92 * bus_dmamem_alloc(9) does. 93 * 94 * Note the sizeof(struct vring_desc) is 16 bytes. 95 */ 96 #define VIRTIO_MAX_INDIRECT ((int) (PAGE_SIZE / 16)) 97 98 /* 99 * VirtIO instance variables indices. 100 */ 101 #define VIRTIO_IVAR_DEVTYPE 1 102 #define VIRTIO_IVAR_FEATURE_DESC 2 103 104 struct virtio_feature_desc { 105 uint64_t vfd_val; 106 const char *vfd_str; 107 }; 108 109 const char *virtio_device_name(uint16_t devid); 110 int virtio_get_device_type(device_t dev); 111 void virtio_set_feature_desc(device_t dev, 112 struct virtio_feature_desc *feature_desc); 113 void virtio_describe(device_t dev, const char *msg, 114 uint64_t features, struct virtio_feature_desc *feature_desc); 115 116 /* 117 * VirtIO Bus Methods. 118 */ 119 uint64_t virtio_negotiate_features(device_t dev, uint64_t child_features); 120 int virtio_alloc_virtqueues(device_t dev, int nvqs, 121 struct vq_alloc_info *info); 122 /* Allocate the interrupt resources. */ 123 /* 124 * The cpus array must be allocated, and contains -1 or cpuid for each IRQ. 125 * 126 * This will either allocate all the irqs, and fill in the actual cpus, and 127 * return 0, or it will fail and return the number of irq vectors that it 128 * managed to get before aborting in "int *cnt". 129 * The driver is supposed to check whether the chosen cpu cores match 130 * the expectations. 131 * 132 * Driver should specify use_config as 1, if a configuration should be 133 * preferred, where the configuration change notification can be handled 134 * efficiently. This only takes effect when a more efficient 135 * 136 * Fails if any interrupts are already allocated. 137 * Caller should check *cnt value after call, to check if all requested IRQS 138 * were actually allocated. 139 */ 140 int virtio_intr_alloc(device_t dev, int *cnt, int use_config, int *cpus); 141 /* Release all the interrupts, fails if any is currently in use */ 142 int virtio_intr_release(device_t dev); 143 /* Activate a hardware interrupt. */ 144 int virtio_setup_intr(device_t dev, uint irq, lwkt_serialize_t); 145 int virtio_teardown_intr(device_t dev, uint irq); 146 /* 147 * Bind the config-notification (-1), or a virtqueue (>= 0) to the irq. 148 * 149 * If the IRQ is an MSI-X, which is also mapped to a virtqueue, the driver 150 * will get a notification callback on each interrupt, whereas if irq is a 151 * legacy IRQ, the virtio device can check the ISR to determine if the 152 * configuration was updated. 153 */ 154 int virtio_bind_intr(device_t dev, uint irq, int what, 155 driver_intr_t handler, void *arg); 156 /* Similarly, -1 is the notification IRQ, >= 0 are the virtqueues. */ 157 int virtio_unbind_intr(device_t dev, int what); 158 int virtio_with_feature(device_t dev, uint64_t feature); 159 /* Get number of interrupts that can probably be allocated. */ 160 int virtio_intr_count(device_t dev); 161 void virtio_stop(device_t dev); 162 int virtio_reinit(device_t dev, uint64_t features); 163 void virtio_reinit_complete(device_t dev); 164 165 /* 166 * Read/write a variable amount from the device specific (ie, network) 167 * configuration region. This region is encoded in the same endian as 168 * the guest. 169 */ 170 void virtio_read_device_config(device_t dev, bus_size_t offset, 171 void *dst, int length); 172 void virtio_write_device_config(device_t dev, bus_size_t offset, 173 void *src, int length); 174 175 /* Inlined device specific read/write functions for common lengths. */ 176 #define VIRTIO_RDWR_DEVICE_CONFIG(size, type) \ 177 static inline type \ 178 __CONCAT(virtio_read_dev_config_,size)(device_t dev, \ 179 bus_size_t offset) \ 180 { \ 181 type val; \ 182 virtio_read_device_config(dev, offset, &val, sizeof(type)); \ 183 return (val); \ 184 } \ 185 \ 186 static inline void \ 187 __CONCAT(virtio_write_dev_config_,size)(device_t dev, \ 188 bus_size_t offset, type val) \ 189 { \ 190 virtio_write_device_config(dev, offset, &val, sizeof(type)); \ 191 } 192 193 VIRTIO_RDWR_DEVICE_CONFIG(1, uint8_t); 194 VIRTIO_RDWR_DEVICE_CONFIG(2, uint16_t); 195 VIRTIO_RDWR_DEVICE_CONFIG(4, uint32_t); 196 197 #endif /* _VIRTIO_H_ */ 198