#ifndef _LINUX_VHOST_H #define _LINUX_VHOST_H /* Userspace interface for in-kernel virtio accelerators. */ /* vhost is used to reduce the number of system calls involved in virtio. * * Existing virtio net code is used in the guest without modification. * * This header includes interface used by userspace hypervisor for * device configuration. */ #include <linux/types.h> #include <linux/ioctl.h> #include <linux/virtio_config.h> #include <linux/virtio_ring.h> struct vhost_vring_state { unsigned int index; unsigned int num; }; struct vhost_vring_file { unsigned int index; int fd; /* Pass -1 to unbind from file. */ }; struct vhost_vring_addr { unsigned int index; /* Option flags. */ unsigned int flags; /* Flag values: */ /* Whether log address is valid. If set enables logging. */ #define VHOST_VRING_F_LOG 0 /* Start of array of descriptors (virtually contiguous) */ __u64 desc_user_addr; /* Used structure address. Must be 32 bit aligned */ __u64 used_user_addr; /* Available structure address. Must be 16 bit aligned */ __u64 avail_user_addr; /* Logging support. */ /* Log writes to used structure, at offset calculated from specified * address. Address must be 32 bit aligned. */ __u64 log_guest_addr; }; struct vhost_memory_region { __u64 guest_phys_addr; __u64 memory_size; /* bytes */ __u64 userspace_addr; __u64 flags_padding; /* No flags are currently specified. */ }; /* All region addresses and sizes must be 4K aligned. */ #define VHOST_PAGE_SIZE 0x1000 struct vhost_memory { __u32 nregions; __u32 padding; struct vhost_memory_region regions[0]; }; /* ioctls */ #define VHOST_VIRTIO 0xAF /* Features bitmask for forward compatibility. Transport bits are used for * vhost specific features. */ #define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64) #define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64) /* Set current process as the (exclusive) owner of this file descriptor. This * must be called before any other vhost command. Further calls to * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */ #define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01) /* Give up ownership, and reset the device to default values. * Allows subsequent call to VHOST_OWNER_SET to succeed. */ #define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02) /* Set up/modify memory layout */ #define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory) /* Write logging setup. */ /* Memory writes can optionally be logged by setting bit at an offset * (calculated from the physical address) from specified log base. * The bit is set using an atomic 32 bit operation. */ /* Set base address for logging. */ #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64) /* Specify an eventfd file descriptor to signal on log write. */ #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int) /* Ring setup. */ /* Set number of descriptors in ring. This parameter can not * be modified while ring is running (bound to a device). */ #define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state) /* Set addresses for the ring. */ #define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr) /* Base value where queue looks for available descriptors */ #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state) /* Get accessor: reads index, writes value in num */ #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state) /* The following ioctls use eventfd file descriptors to signal and poll * for events. */ /* Set eventfd to poll for added buffers */ #define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file) /* Set eventfd to signal when buffers have beed used */ #define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file) /* Set eventfd to signal an error */ #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file) /* VHOST_NET specific defines */ /* Attach virtio net ring to a raw socket, or tap device. * The socket must be already bound to an ethernet device, this device will be * used for transmit. Pass fd -1 to unbind from the socket and the transmit * device. This can be used to stop the ring (e.g. for migration). */ #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file) /* Feature bits */ /* Log all write descriptors. Can be changed while device is active. */ #define VHOST_F_LOG_ALL 26 /* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */ #define VHOST_NET_F_VIRTIO_NET_HDR 27 #endif