/* * Vhost User library * * Copyright (c) 2016 Red Hat, Inc. * * Authors: * Victor Kaplansky * Marc-André Lureau * * This work is licensed under the terms of the GNU GPL, version 2 or * later. See the COPYING file in the top-level directory. */ #ifndef LIBVHOST_USER_H #define LIBVHOST_USER_H #include #include #include #include #include #include "standard-headers/linux/virtio_ring.h" /* Based on qemu/hw/virtio/vhost-user.c */ #define VHOST_USER_F_PROTOCOL_FEATURES 30 #define VHOST_LOG_PAGE 4096 #define VHOST_MAX_NR_VIRTQUEUE 8 #define VIRTQUEUE_MAX_SIZE 1024 #define VHOST_MEMORY_MAX_NREGIONS 8 typedef enum VhostSetConfigType { VHOST_SET_CONFIG_TYPE_MASTER = 0, VHOST_SET_CONFIG_TYPE_MIGRATION = 1, } VhostSetConfigType; /* * Maximum size of virtio device config space */ #define VHOST_USER_MAX_CONFIG_SIZE 256 enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_MQ = 0, VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1, VHOST_USER_PROTOCOL_F_RARP = 2, VHOST_USER_PROTOCOL_F_REPLY_ACK = 3, VHOST_USER_PROTOCOL_F_NET_MTU = 4, VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5, VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6, VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7, VHOST_USER_PROTOCOL_F_PAGEFAULT = 8, VHOST_USER_PROTOCOL_F_MAX }; #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1) typedef enum VhostUserRequest { VHOST_USER_NONE = 0, VHOST_USER_GET_FEATURES = 1, VHOST_USER_SET_FEATURES = 2, VHOST_USER_SET_OWNER = 3, VHOST_USER_RESET_OWNER = 4, VHOST_USER_SET_MEM_TABLE = 5, VHOST_USER_SET_LOG_BASE = 6, VHOST_USER_SET_LOG_FD = 7, VHOST_USER_SET_VRING_NUM = 8, VHOST_USER_SET_VRING_ADDR = 9, VHOST_USER_SET_VRING_BASE = 10, VHOST_USER_GET_VRING_BASE = 11, VHOST_USER_SET_VRING_KICK = 12, VHOST_USER_SET_VRING_CALL = 13, VHOST_USER_SET_VRING_ERR = 14, VHOST_USER_GET_PROTOCOL_FEATURES = 15, VHOST_USER_SET_PROTOCOL_FEATURES = 16, VHOST_USER_GET_QUEUE_NUM = 17, VHOST_USER_SET_VRING_ENABLE = 18, VHOST_USER_SEND_RARP = 19, VHOST_USER_NET_SET_MTU = 20, VHOST_USER_SET_SLAVE_REQ_FD = 21, VHOST_USER_IOTLB_MSG = 22, VHOST_USER_SET_VRING_ENDIAN = 23, VHOST_USER_GET_CONFIG = 24, VHOST_USER_SET_CONFIG = 25, VHOST_USER_MAX } VhostUserRequest; typedef struct VhostUserMemoryRegion { uint64_t guest_phys_addr; uint64_t memory_size; uint64_t userspace_addr; uint64_t mmap_offset; } VhostUserMemoryRegion; typedef struct VhostUserMemory { uint32_t nregions; uint32_t padding; VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS]; } VhostUserMemory; typedef struct VhostUserLog { uint64_t mmap_size; uint64_t mmap_offset; } VhostUserLog; typedef struct VhostUserConfig { uint32_t offset; uint32_t size; uint32_t flags; uint8_t region[VHOST_USER_MAX_CONFIG_SIZE]; } VhostUserConfig; static VhostUserConfig c __attribute__ ((unused)); #define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \ + sizeof(c.size) \ + sizeof(c.flags)) #if defined(_WIN32) # define VU_PACKED __attribute__((gcc_struct, packed)) #else # define VU_PACKED __attribute__((packed)) #endif typedef struct VhostUserMsg { VhostUserRequest request; #define VHOST_USER_VERSION_MASK (0x3) #define VHOST_USER_REPLY_MASK (0x1 << 2) uint32_t flags; uint32_t size; /* the following payload size */ union { #define VHOST_USER_VRING_IDX_MASK (0xff) #define VHOST_USER_VRING_NOFD_MASK (0x1 << 8) uint64_t u64; struct vhost_vring_state state; struct vhost_vring_addr addr; VhostUserMemory memory; VhostUserLog log; VhostUserConfig config; } payload; int fds[VHOST_MEMORY_MAX_NREGIONS]; int fd_num; uint8_t *data; } VU_PACKED VhostUserMsg; typedef struct VuDevRegion { /* Guest Physical address. */ uint64_t gpa; /* Memory region size. */ uint64_t size; /* QEMU virtual address (userspace). */ uint64_t qva; /* Starting offset in our mmaped space. */ uint64_t mmap_offset; /* Start address of mmaped space. */ uint64_t mmap_addr; } VuDevRegion; typedef struct VuDev VuDev; typedef uint64_t (*vu_get_features_cb) (VuDev *dev); typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features); typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg, int *do_reply); typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started); typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx); typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len); typedef int (*vu_set_config_cb) (VuDev *dev, const uint8_t *data, uint32_t offset, uint32_t size, uint32_t flags); typedef struct VuDevIface { /* called by VHOST_USER_GET_FEATURES to get the features bitmask */ vu_get_features_cb get_features; /* enable vhost implementation features */ vu_set_features_cb set_features; /* get the protocol feature bitmask from the underlying vhost * implementation */ vu_get_features_cb get_protocol_features; /* enable protocol features in the underlying vhost implementation. */ vu_set_features_cb set_protocol_features; /* process_msg is called for each vhost-user message received */ /* skip libvhost-user processing if return value != 0 */ vu_process_msg_cb process_msg; /* tells when queues can be processed */ vu_queue_set_started_cb queue_set_started; /* * If the queue is processed in order, in which case it will be * resumed to vring.used->idx. This can help to support resuming * on unmanaged exit/crash. */ vu_queue_is_processed_in_order_cb queue_is_processed_in_order; /* get the config space of the device */ vu_get_config_cb get_config; /* set the config space of the device */ vu_set_config_cb set_config; } VuDevIface; typedef void (*vu_queue_handler_cb) (VuDev *dev, int qidx); typedef struct VuRing { unsigned int num; struct vring_desc *desc; struct vring_avail *avail; struct vring_used *used; uint64_t log_guest_addr; uint32_t flags; } VuRing; typedef struct VuVirtq { VuRing vring; /* Next head to pop */ uint16_t last_avail_idx; /* Last avail_idx read from VQ. */ uint16_t shadow_avail_idx; uint16_t used_idx; /* Last used index value we have signalled on */ uint16_t signalled_used; /* Last used index value we have signalled on */ bool signalled_used_valid; /* Notification enabled? */ bool notification; int inuse; vu_queue_handler_cb handler; int call_fd; int kick_fd; int err_fd; unsigned int enable; bool started; } VuVirtq; enum VuWatchCondtion { VU_WATCH_IN = POLLIN, VU_WATCH_OUT = POLLOUT, VU_WATCH_PRI = POLLPRI, VU_WATCH_ERR = POLLERR, VU_WATCH_HUP = POLLHUP, }; typedef void (*vu_panic_cb) (VuDev *dev, const char *err); typedef void (*vu_watch_cb) (VuDev *dev, int condition, void *data); typedef void (*vu_set_watch_cb) (VuDev *dev, int fd, int condition, vu_watch_cb cb, void *data); typedef void (*vu_remove_watch_cb) (VuDev *dev, int fd); struct VuDev { int sock; uint32_t nregions; VuDevRegion regions[VHOST_MEMORY_MAX_NREGIONS]; VuVirtq vq[VHOST_MAX_NR_VIRTQUEUE]; int log_call_fd; int slave_fd; uint64_t log_size; uint8_t *log_table; uint64_t features; uint64_t protocol_features; bool broken; /* @set_watch: add or update the given fd to the watch set, * call cb when condition is met */ vu_set_watch_cb set_watch; /* @remove_watch: remove the given fd from the watch set */ vu_remove_watch_cb remove_watch; /* @panic: encountered an unrecoverable error, you may try to * re-initialize */ vu_panic_cb panic; const VuDevIface *iface; }; typedef struct VuVirtqElement { unsigned int index; unsigned int out_num; unsigned int in_num; struct iovec *in_sg; struct iovec *out_sg; } VuVirtqElement; /** * vu_init: * @dev: a VuDev context * @socket: the socket connected to vhost-user master * @panic: a panic callback * @set_watch: a set_watch callback * @remove_watch: a remove_watch callback * @iface: a VuDevIface structure with vhost-user device callbacks * * Intializes a VuDev vhost-user context. **/ void vu_init(VuDev *dev, int socket, vu_panic_cb panic, vu_set_watch_cb set_watch, vu_remove_watch_cb remove_watch, const VuDevIface *iface); /** * vu_deinit: * @dev: a VuDev context * * Cleans up the VuDev context */ void vu_deinit(VuDev *dev); /** * vu_dispatch: * @dev: a VuDev context * * Process one vhost-user message. * * Returns: TRUE on success, FALSE on failure. */ bool vu_dispatch(VuDev *dev); /** * vu_gpa_to_va: * @dev: a VuDev context * @plen: guest memory size * @guest_addr: guest address * * Translate a guest address to a pointer. Returns NULL on failure. */ void *vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr); /** * vu_get_queue: * @dev: a VuDev context * @qidx: queue index * * Returns the queue number @qidx. */ VuVirtq *vu_get_queue(VuDev *dev, int qidx); /** * vu_set_queue_handler: * @dev: a VuDev context * @vq: a VuVirtq queue * @handler: the queue handler callback * * Set the queue handler. This function may be called several times * for the same queue. If called with NULL @handler, the handler is * removed. */ void vu_set_queue_handler(VuDev *dev, VuVirtq *vq, vu_queue_handler_cb handler); /** * vu_queue_set_notification: * @dev: a VuDev context * @vq: a VuVirtq queue * @enable: state * * Set whether the queue notifies (via event index or interrupt) */ void vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable); /** * vu_queue_enabled: * @dev: a VuDev context * @vq: a VuVirtq queue * * Returns: whether the queue is enabled. */ bool vu_queue_enabled(VuDev *dev, VuVirtq *vq); /** * vu_queue_started: * @dev: a VuDev context * @vq: a VuVirtq queue * * Returns: whether the queue is started. */ bool vu_queue_started(const VuDev *dev, const VuVirtq *vq); /** * vu_queue_empty: * @dev: a VuDev context * @vq: a VuVirtq queue * * Returns: true if the queue is empty or not ready. */ bool vu_queue_empty(VuDev *dev, VuVirtq *vq); /** * vu_queue_notify: * @dev: a VuDev context * @vq: a VuVirtq queue * * Request to notify the queue via callfd (skipped if unnecessary) */ void vu_queue_notify(VuDev *dev, VuVirtq *vq); /** * vu_queue_pop: * @dev: a VuDev context * @vq: a VuVirtq queue * @sz: the size of struct to return (must be >= VuVirtqElement) * * Returns: a VuVirtqElement filled from the queue or NULL. The * returned element must be free()-d by the caller. */ void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz); /** * vu_queue_rewind: * @dev: a VuDev context * @vq: a VuVirtq queue * @num: number of elements to push back * * Pretend that elements weren't popped from the virtqueue. The next * virtqueue_pop() will refetch the oldest element. * * Returns: true on success, false if @num is greater than the number of in use * elements. */ bool vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num); /** * vu_queue_fill: * @dev: a VuDev context * @vq: a VuVirtq queue * @elem: a VuVirtqElement * @len: length in bytes to write * @idx: optional offset for the used ring index (0 in general) * * Fill the used ring with @elem element. */ void vu_queue_fill(VuDev *dev, VuVirtq *vq, const VuVirtqElement *elem, unsigned int len, unsigned int idx); /** * vu_queue_push: * @dev: a VuDev context * @vq: a VuVirtq queue * @elem: a VuVirtqElement * @len: length in bytes to write * * Helper that combines vu_queue_fill() with a vu_queue_flush(). */ void vu_queue_push(VuDev *dev, VuVirtq *vq, const VuVirtqElement *elem, unsigned int len); /** * vu_queue_flush: * @dev: a VuDev context * @vq: a VuVirtq queue * @num: number of elements to flush * * Mark the last number of elements as done (used.idx is updated by * num elements). */ void vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int num); /** * vu_queue_get_avail_bytes: * @dev: a VuDev context * @vq: a VuVirtq queue * @in_bytes: in bytes * @out_bytes: out bytes * @max_in_bytes: stop counting after max_in_bytes * @max_out_bytes: stop counting after max_out_bytes * * Count the number of available bytes, up to max_in_bytes/max_out_bytes. */ void vu_queue_get_avail_bytes(VuDev *vdev, VuVirtq *vq, unsigned int *in_bytes, unsigned int *out_bytes, unsigned max_in_bytes, unsigned max_out_bytes); /** * vu_queue_avail_bytes: * @dev: a VuDev context * @vq: a VuVirtq queue * @in_bytes: expected in bytes * @out_bytes: expected out bytes * * Returns: true if in_bytes <= in_total && out_bytes <= out_total */ bool vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes, unsigned int out_bytes); #endif /* LIBVHOST_USER_H */