| Michael S. Tsirkin | 3a4d5c9 | 2010-01-14 06:17:27 +0000 | [diff] [blame] | 1 | #ifndef _LINUX_VHOST_H |
| 2 | #define _LINUX_VHOST_H |
| 3 | /* Userspace interface for in-kernel virtio accelerators. */ |
| 4 | |
| 5 | /* vhost is used to reduce the number of system calls involved in virtio. |
| 6 | * |
| 7 | * Existing virtio net code is used in the guest without modification. |
| 8 | * |
| 9 | * This header includes interface used by userspace hypervisor for |
| 10 | * device configuration. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/types.h> |
| 14 | #include <linux/compiler.h> |
| 15 | #include <linux/ioctl.h> |
| 16 | #include <linux/virtio_config.h> |
| 17 | #include <linux/virtio_ring.h> |
| 18 | |
| 19 | struct vhost_vring_state { |
| 20 | unsigned int index; |
| 21 | unsigned int num; |
| 22 | }; |
| 23 | |
| 24 | struct vhost_vring_file { |
| 25 | unsigned int index; |
| 26 | int fd; /* Pass -1 to unbind from file. */ |
| 27 | |
| 28 | }; |
| 29 | |
| 30 | struct vhost_vring_addr { |
| 31 | unsigned int index; |
| 32 | /* Option flags. */ |
| 33 | unsigned int flags; |
| 34 | /* Flag values: */ |
| 35 | /* Whether log address is valid. If set enables logging. */ |
| 36 | #define VHOST_VRING_F_LOG 0 |
| 37 | |
| 38 | /* Start of array of descriptors (virtually contiguous) */ |
| 39 | __u64 desc_user_addr; |
| 40 | /* Used structure address. Must be 32 bit aligned */ |
| 41 | __u64 used_user_addr; |
| 42 | /* Available structure address. Must be 16 bit aligned */ |
| 43 | __u64 avail_user_addr; |
| 44 | /* Logging support. */ |
| 45 | /* Log writes to used structure, at offset calculated from specified |
| 46 | * address. Address must be 32 bit aligned. */ |
| 47 | __u64 log_guest_addr; |
| 48 | }; |
| 49 | |
| 50 | struct vhost_memory_region { |
| 51 | __u64 guest_phys_addr; |
| 52 | __u64 memory_size; /* bytes */ |
| 53 | __u64 userspace_addr; |
| 54 | __u64 flags_padding; /* No flags are currently specified. */ |
| 55 | }; |
| 56 | |
| 57 | /* All region addresses and sizes must be 4K aligned. */ |
| 58 | #define VHOST_PAGE_SIZE 0x1000 |
| 59 | |
| 60 | struct vhost_memory { |
| 61 | __u32 nregions; |
| 62 | __u32 padding; |
| 63 | struct vhost_memory_region regions[0]; |
| 64 | }; |
| 65 | |
| 66 | /* ioctls */ |
| 67 | |
| 68 | #define VHOST_VIRTIO 0xAF |
| 69 | |
| 70 | /* Features bitmask for forward compatibility. Transport bits are used for |
| 71 | * vhost specific features. */ |
| 72 | #define VHOST_GET_FEATURES _IOR(VHOST_VIRTIO, 0x00, __u64) |
| 73 | #define VHOST_SET_FEATURES _IOW(VHOST_VIRTIO, 0x00, __u64) |
| 74 | |
| 75 | /* Set current process as the (exclusive) owner of this file descriptor. This |
| 76 | * must be called before any other vhost command. Further calls to |
| 77 | * VHOST_OWNER_SET fail until VHOST_OWNER_RESET is called. */ |
| 78 | #define VHOST_SET_OWNER _IO(VHOST_VIRTIO, 0x01) |
| 79 | /* Give up ownership, and reset the device to default values. |
| 80 | * Allows subsequent call to VHOST_OWNER_SET to succeed. */ |
| 81 | #define VHOST_RESET_OWNER _IO(VHOST_VIRTIO, 0x02) |
| 82 | |
| 83 | /* Set up/modify memory layout */ |
| 84 | #define VHOST_SET_MEM_TABLE _IOW(VHOST_VIRTIO, 0x03, struct vhost_memory) |
| 85 | |
| 86 | /* Write logging setup. */ |
| 87 | /* Memory writes can optionally be logged by setting bit at an offset |
| 88 | * (calculated from the physical address) from specified log base. |
| 89 | * The bit is set using an atomic 32 bit operation. */ |
| 90 | /* Set base address for logging. */ |
| 91 | #define VHOST_SET_LOG_BASE _IOW(VHOST_VIRTIO, 0x04, __u64) |
| 92 | /* Specify an eventfd file descriptor to signal on log write. */ |
| 93 | #define VHOST_SET_LOG_FD _IOW(VHOST_VIRTIO, 0x07, int) |
| 94 | |
| 95 | /* Ring setup. */ |
| 96 | /* Set number of descriptors in ring. This parameter can not |
| 97 | * be modified while ring is running (bound to a device). */ |
| 98 | #define VHOST_SET_VRING_NUM _IOW(VHOST_VIRTIO, 0x10, struct vhost_vring_state) |
| 99 | /* Set addresses for the ring. */ |
| 100 | #define VHOST_SET_VRING_ADDR _IOW(VHOST_VIRTIO, 0x11, struct vhost_vring_addr) |
| 101 | /* Base value where queue looks for available descriptors */ |
| 102 | #define VHOST_SET_VRING_BASE _IOW(VHOST_VIRTIO, 0x12, struct vhost_vring_state) |
| 103 | /* Get accessor: reads index, writes value in num */ |
| 104 | #define VHOST_GET_VRING_BASE _IOWR(VHOST_VIRTIO, 0x12, struct vhost_vring_state) |
| 105 | |
| 106 | /* The following ioctls use eventfd file descriptors to signal and poll |
| 107 | * for events. */ |
| 108 | |
| 109 | /* Set eventfd to poll for added buffers */ |
| 110 | #define VHOST_SET_VRING_KICK _IOW(VHOST_VIRTIO, 0x20, struct vhost_vring_file) |
| 111 | /* Set eventfd to signal when buffers have beed used */ |
| 112 | #define VHOST_SET_VRING_CALL _IOW(VHOST_VIRTIO, 0x21, struct vhost_vring_file) |
| 113 | /* Set eventfd to signal an error */ |
| 114 | #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file) |
| 115 | |
| 116 | /* VHOST_NET specific defines */ |
| 117 | |
| 118 | /* Attach virtio net ring to a raw socket, or tap device. |
| 119 | * The socket must be already bound to an ethernet device, this device will be |
| 120 | * used for transmit. Pass fd -1 to unbind from the socket and the transmit |
| 121 | * device. This can be used to stop the ring (e.g. for migration). */ |
| 122 | #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct vhost_vring_file) |
| 123 | |
| 124 | /* Feature bits */ |
| 125 | /* Log all write descriptors. Can be changed while device is active. */ |
| 126 | #define VHOST_F_LOG_ALL 26 |
| 127 | /* vhost-net should add virtio_net_hdr for RX, and strip for TX packets. */ |
| 128 | #define VHOST_NET_F_VIRTIO_NET_HDR 27 |
| 129 | |
| 130 | #endif |