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 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 69 struct vhost_msg { 70 int type; 71 union { 72 struct vhost_iotlb_msg iotlb; 73 __u8 padding[64]; 74 }; 75 }; 76 77 struct vhost_memory_region { 78 __u64 guest_phys_addr; 79 __u64 memory_size; /* bytes */ 80 __u64 userspace_addr; 81 __u64 flags_padding; /* No flags are currently specified. */ 82 }; 83 84 /* All region addresses and sizes must be 4K aligned. */ 85 #define VHOST_PAGE_SIZE 0x1000 86 87 struct vhost_memory { 88 __u32 nregions; 89 __u32 padding; 90 struct vhost_memory_region regions[0]; 91 }; 92 93 /* ioctls */ 94 95 #define VHOST_VIRTIO 0xAF 96 97 /* Features bitmask for forward compatibility. Transport bits are used for 98 * vhost specific features. */ 99 #define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64) 100 #define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64) 101 102 /* Set current process as the (exclusive) owner of this file descriptor. This 103 * must be called before any other vhost command. Further calls to 104 * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */ 105 #define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01) 106 /* Give up ownership, and reset the device to default values. 107 * Allows subsequent call to VHOST_OWNER_SET to succeed. */ 108 #define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02) 109 110 /* Set up/modify memory layout */ 111 #define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory) 112 113 /* Write logging setup. */ 114 /* Memory writes can optionally be logged by setting bit at an offset 115 * (calculated from the physical address) from specified log base. 116 * The bit is set using an atomic 32 bit operation. */ 117 /* Set base address for logging. */ 118 #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64) 119 /* Specify an eventfd file descriptor to signal on log write. */ 120 #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int) 121 122 /* Ring setup. */ 123 /* Set number of descriptors in ring. This parameter can not 124 * be modified while ring is running (bound to a device). */ 125 #define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state) 126 /* Set addresses for the ring. */ 127 #define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr) 128 /* Base value where queue looks for available descriptors */ 129 #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state) 130 /* Get accessor: reads index, writes value in num */ 131 #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state) 132 133 /* Set the vring byte order in num. Valid values are VHOST_VRING_LITTLE_ENDIAN 134 * or VHOST_VRING_BIG_ENDIAN (other values return -EINVAL). 135 * The byte order cannot be changed while the device is active: trying to do so 136 * returns -EBUSY. 137 * This is a legacy only API that is simply ignored when VIRTIO_F_VERSION_1 is 138 * set. 139 * Not all kernel configurations support this ioctl, but all configurations that 140 * support SET also support GET. 141 */ 142 #define VHOST_VRING_LITTLE_ENDIAN 0 143 #define VHOST_VRING_BIG_ENDIAN 1 144 #define VHOST_SET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x13, struct vhost_vring_state) 145 #define VHOST_GET_VRING_ENDIAN _IOW(VHOST_VIRTIO, 0x14, struct vhost_vring_state) 146 147 /* The following ioctls use eventfd file descriptors to signal and poll 148 * for events. */ 149 150 /* Set eventfd to poll for added buffers */ 151 #define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file) 152 /* Set eventfd to signal when buffers have beed used */ 153 #define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file) 154 /* Set eventfd to signal an error */ 155 #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file) 156 /* Set busy loop timeout (in us) */ 157 #define VHOST_SET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x23, \ 158 struct vhost_vring_state) 159 /* Get busy loop timeout (in us) */ 160 #define VHOST_GET_VRING_BUSYLOOP_TIMEOUT _IOW(VHOST_VIRTIO, 0x24, \ 161 struct vhost_vring_state) 162 163 /* VHOST_NET specific defines */ 164 165 /* Attach virtio net ring to a raw socket, or tap device. 166 * The socket must be already bound to an ethernet device, this device will be 167 * used for transmit. Pass fd -1 to unbind from the socket and the transmit 168 * device. This can be used to stop the ring (e.g. for migration). */ 169 #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file) 170 171 /* Feature bits */ 172 /* Log all write descriptors. Can be changed while device is active. */ 173 #define VHOST_F_LOG_ALL 26 174 /* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */ 175 #define VHOST_NET_F_VIRTIO_NET_HDR 27 176 177 /* VHOST_SCSI specific definitions */ 178 179 /* 180 * Used by QEMU userspace to ensure a consistent vhost-scsi ABI. 181 * 182 * ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate + 183 * RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage 184 * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct vhost_scsi_target. 185 * All the targets under vhost_wwpn can be seen and used by guset. 186 */ 187 188 #define VHOST_SCSI_ABI_VERSION 1 189 190 struct vhost_scsi_target { 191 int abi_version; 192 char vhost_wwpn[224]; /* TRANSPORT_IQN_LEN */ 193 unsigned short vhost_tpgt; 194 unsigned short reserved; 195 }; 196 197 #define VHOST_SCSI_SET_ENDPOINT _IOW(VHOST_VIRTIO, 0x40, struct vhost_scsi_target) 198 #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target) 199 /* Changing this breaks userspace. */ 200 #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int) 201 /* Set and get the events missed flag */ 202 #define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32) 203 #define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32) 204 205 /* VHOST_VSOCK specific defines */ 206 207 #define VHOST_VSOCK_SET_GUEST_CID _IOW(VHOST_VIRTIO, 0x60, __u64) 208 #define VHOST_VSOCK_SET_RUNNING _IOW(VHOST_VIRTIO, 0x61, int) 209 210 #endif 211