#ifndef _VHOST_H #define _VHOST_H #include <linux/eventfd.h> #include <linux/vhost.h> #include <linux/mm.h> #include <linux/mutex.h> #include <linux/poll.h> #include <linux/file.h> #include <linux/uio.h> #include <linux/virtio_config.h> #include <linux/virtio_ring.h> #include <linux/atomic.h> struct vhost_work; typedef void (*vhost_work_fn_t)(struct vhost_work *work); struct vhost_work { struct list_head node; vhost_work_fn_t fn; wait_queue_head_t done; int flushing; unsigned queue_seq; unsigned done_seq; }; /* Poll a file (eventfd or socket) */ /* Note: there's nothing vhost specific about this structure. */ struct vhost_poll { poll_table table; wait_queue_head_t *wqh; wait_queue_t wait; struct vhost_work work; unsigned long mask; struct vhost_dev *dev; }; void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn); void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work); bool vhost_has_work(struct vhost_dev *dev); void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, unsigned long mask, struct vhost_dev *dev); int vhost_poll_start(struct vhost_poll *poll, struct file *file); void vhost_poll_stop(struct vhost_poll *poll); void vhost_poll_flush(struct vhost_poll *poll); void vhost_poll_queue(struct vhost_poll *poll); void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work); long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp); struct vhost_log { u64 addr; u64 len; }; /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; /* The actual ring of buffers. */ struct mutex mutex; unsigned int num; struct vring_desc __user *desc; struct vring_avail __user *avail; struct vring_used __user *used; struct file *kick; struct file *call; struct file *error; struct eventfd_ctx *call_ctx; struct eventfd_ctx *error_ctx; struct eventfd_ctx *log_ctx; struct vhost_poll poll; /* The routine to call when the Guest pings us, or timeout. */ vhost_work_fn_t handle_kick; /* Last available index we saw. */ u16 last_avail_idx; /* Caches available index value from user. */ u16 avail_idx; /* Last index we used. */ u16 last_used_idx; /* Used flags */ u16 used_flags; /* Last used index value we have signalled on */ u16 signalled_used; /* Last used index value we have signalled on */ bool signalled_used_valid; /* Log writes to used structure. */ bool log_used; u64 log_addr; struct iovec iov[UIO_MAXIOV]; struct iovec *indirect; struct vring_used_elem *heads; /* Protected by virtqueue mutex. */ struct vhost_memory *memory; void *private_data; u64 acked_features; /* Log write descriptors */ void __user *log_base; struct vhost_log *log; /* Ring endianness. Defaults to legacy native endianness. * Set to true when starting a modern virtio device. */ bool is_le; #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY /* Ring endianness requested by userspace for cross-endian support. */ bool user_be; #endif u32 busyloop_timeout; }; struct vhost_dev { struct vhost_memory *memory; struct mm_struct *mm; struct mutex mutex; struct vhost_virtqueue **vqs; int nvqs; struct file *log_file; struct eventfd_ctx *log_ctx; spinlock_t work_lock; struct list_head work_list; struct task_struct *worker; }; void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs); long vhost_dev_set_owner(struct vhost_dev *dev); bool vhost_dev_has_owner(struct vhost_dev *dev); long vhost_dev_check_owner(struct vhost_dev *); struct vhost_memory *vhost_dev_reset_owner_prepare(void); void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *); void vhost_dev_cleanup(struct vhost_dev *, bool locked); void vhost_dev_stop(struct vhost_dev *); long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp); long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp); int vhost_vq_access_ok(struct vhost_virtqueue *vq); int vhost_log_access_ok(struct vhost_dev *); int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num); void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); int vhost_vq_init_access(struct vhost_virtqueue *); int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len); int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, unsigned int id, int len); void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, unsigned int log_num, u64 len); #define vq_err(vq, fmt, ...) do { \ pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \ if ((vq)->error_ctx) \ eventfd_signal((vq)->error_ctx, 1);\ } while (0) enum { VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) | (1ULL << VIRTIO_RING_F_INDIRECT_DESC) | (1ULL << VIRTIO_RING_F_EVENT_IDX) | (1ULL << VHOST_F_LOG_ALL) | (1ULL << VIRTIO_F_ANY_LAYOUT) | (1ULL << VIRTIO_F_VERSION_1) }; static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit) { return vq->acked_features & (1ULL << bit); } #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq) { return vq->is_le; } #else static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq) { return virtio_legacy_is_little_endian() || vq->is_le; } #endif /* Memory accessors */ static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val) { return __virtio16_to_cpu(vhost_is_little_endian(vq), val); } static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val) { return __cpu_to_virtio16(vhost_is_little_endian(vq), val); } static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val) { return __virtio32_to_cpu(vhost_is_little_endian(vq), val); } static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val) { return __cpu_to_virtio32(vhost_is_little_endian(vq), val); } static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val) { return __virtio64_to_cpu(vhost_is_little_endian(vq), val); } static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val) { return __cpu_to_virtio64(vhost_is_little_endian(vq), val); } #endif