1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef _LINUX_VHOST_H 3 #define _LINUX_VHOST_H 4 /* Userspace interface for in-kernel virtio accelerators. */ 5 6 /* vhost is used to reduce the number of system calls involved in virtio. 7 * 8 * Existing virtio net code is used in the guest without modification. 9 * 10 * This header includes interface used by userspace hypervisor for 11 * device configuration. 12 */ 13 14 #include <linux/types.h> 15 #include <linux/compiler.h> 16 #include <linux/ioctl.h> 17 #include <linux/virtio_config.h> 18 #include <linux/virtio_ring.h> 19 20 struct vhost_vring_state { 21 unsigned int index; 22 unsigned int num; 23 }; 24 25 struct vhost_vring_file { 26 unsigned int index; 27 int fd; /* Pass -1 to unbind from file. */ 28 29 }; 30 31 struct vhost_vring_addr { 32 unsigned int index; 33 /* Option flags. */ 34 unsigned int flags; 35 /* Flag values: */ 36 /* Whether log address is valid. If set enables logging. */ 37 #define VHOST_VRING_F_LOG 0 38 39 /* Start of array of descriptors (virtually contiguous) */ 40 __u64 desc_user_addr; 41 /* Used structure address. Must be 32 bit aligned */ 42 __u64 used_user_addr; 43 /* Available structure address. Must be 16 bit aligned */ 44 __u64 avail_user_addr; 45 /* Logging support. */ 46 /* Log writes to used structure, at offset calculated from specified 47 * address. Address must be 32 bit aligned. */ 48 __u64 log_guest_addr; 49 }; 50 51 /* no alignment requirement */ 52 struct vhost_iotlb_msg { 53 __u64 iova; 54 __u64 size; 55 __u64 uaddr; 56 #define VHOST_ACCESS_RO 0x1 57 #define VHOST_ACCESS_WO 0x2 58 #define VHOST_ACCESS_RW 0x3 59 __u8 perm; 60 #define VHOST_IOTLB_MISS 1 61 #define VHOST_IOTLB_UPDATE 2 62 #define VHOST_IOTLB_INVALIDATE 3 63 #define VHOST_IOTLB_ACCESS_FAIL 4 64 __u8 type; 65 }; 66 67 #define VHOST_IOTLB_MSG 0x1 68 #define VHOST_IOTLB_MSG_V2 0x2 69 70 struct vhost_msg { 71 int type; 72 union { 73 struct vhost_iotlb_msg iotlb; 74 __u8 padding[64]; 75 }; 76 }; 77 78 struct vhost_msg_v2 { 79 __u32 type; 80 __u32 reserved; 81 union { 82 struct vhost_iotlb_msg iotlb; 83 __u8 padding[64]; 84 }; 85 }; 86 87 struct vhost_memory_region { 88 __u64 guest_phys_addr; 89 __u64 memory_size; /* bytes */ 90 __u64 userspace_addr; 91 __u64 flags_padding; /* No flags are currently specified. */ 92 }; 93 94 /* All region addresses and sizes must be 4K aligned. */ 95 #define VHOST_PAGE_SIZE 0x1000 96 97 struct vhost_memory { 98 __u32 nregions; 99 __u32 padding; 100 struct vhost_memory_region regions[0]; 101 }; 102 103 /* ioctls */ 104 105 #define VHOST_VIRTIO 0xAF 106 107 /* Features bitmask for forward compatibility. Transport bits are used for 108 * vhost specific features. */ 109 #define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64) 110 #define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64) 111 112 /* Set current process as the (exclusive) owner of this file descriptor. This 113 * must be called before any other vhost command. Further calls to 114 * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */ 115 #define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01) 116 /* Give up ownership, and reset the device to default values. 117 * Allows subsequent call to VHOST_OWNER_SET to succeed. */ 118 #define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02) 119 120 /* Set up/modify memory layout */ 121 #define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory) 122 123 /* Write logging setup. */ 124 /* Memory writes can optionally be logged by setting bit at an offset 125 * (calculated from the physical address) from specified log base. 126 * The bit is set using an atomic 32 bit operation. */ 127 /* Set base address for logging. */ 128 #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64) 129 /* Specify an eventfd file descriptor to signal on log write. */ 130 #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int) 131 132 /* Ring setup. */ 133 /* Set number of descriptors in ring. This parameter can not 134 * be modified while ring is running (bound to a device). */ 135 #define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state) 136 /* Set addresses for the ring. */ 137 #define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr) 138 /* Base value where queue looks for available descriptors */ 139 #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state) 140 /* Get accessor: reads index, writes value in num */ 141 #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state) 142 143 /* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN 144 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL). 145 * The byte order cannot be changed while the device is active: trying to do so 146 * returns -EBUSY. 147 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is 148 * set. 149 * Not all kernel configurations support this ioctl, but all configurations that 150 * support SET also support GET. 151 */ 152 #define VHOST_VRING_LITTLE_ENDIAN 0 153 #define VHOST_VRING_BIG_ENDIAN 1 154 #define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state) 155 #define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state) 156 157 /* The following ioctls use eventfd file descriptors to signal and poll 158 * for events. */ 159 160 /* Set eventfd to poll for added buffers */ 161 #define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file) 162 /* Set eventfd to signal when buffers have beed used */ 163 #define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file) 164 /* Set eventfd to signal an error */ 165 #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file) 166 /* Set busy loop timeout (in us) */ 167 #define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \ 168 struct vhost_vring_state) 169 /* Get busy loop timeout (in us) */ 170 #define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \ 171 struct vhost_vring_state) 172 173 /* Set or get vhost backend capability */ 174 175 /* Use message type V2 */ 176 #define VHOST_BACKEND_F_IOTLB_MSG_V2 0x1 177 178 #define VHOST_SET_BACKEND_FEATURES _IOW(VHOST_VIRTIO, 0x25, __u64) 179 #define VHOST_GET_BACKEND_FEATURES _IOR(VHOST_VIRTIO, 0x26, __u64) 180 181 /* VHOST_NET specific defines */ 182 183 /* Attach virtio net ring to a raw socket, or tap device. 184 * The socket must be already bound to an ethernet device, this device will be 185 * used for transmit. Pass fd -1 to unbind from the socket and the transmit 186 * device. This can be used to stop the ring (e.g. for migration). */ 187 #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file) 188 189 /* Feature bits */ 190 /* Log all write descriptors. Can be changed while device is active. */ 191 #define VHOST_F_LOG_ALL 26 192 /* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */ 193 #define VHOST_NET_F_VIRTIO_NET_HDR 27 194 195 /* VHOST_SCSI specific definitions */ 196 197 /* 198 * Used by QEMU userspace to ensure a consistent vhost-scsi ABI. 199 * 200 * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate + 201 * RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage 202 * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct vhost_scsi_target. 203 * All the targets under vhost_wwpn can be seen and used by guset. 204 */ 205 206 #define VHOST_SCSI_ABI_VERSION 1 207 208 struct vhost_scsi_target { 209 int abi_version; 210 char vhost_wwpn[224]; /* TRANSPORT_IQN_LEN */ 211 unsigned short vhost_tpgt; 212 unsigned short reserved; 213 }; 214 215 #define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target) 216 #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target) 217 /* Changing this breaks userspace. */ 218 #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int) 219 /* Set and get the events missed flag */ 220 #define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32) 221 #define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32) 222 223 /* VHOST_VSOCK specific defines */ 224 225 #define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64) 226 #define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int) 227 228 #endif 229