/* SPDX-License-Identifier: GPL-2.0 */#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>#include <linux/vhost_iotlb.h>#include <linux/irqbypass.h>#include <linux/unroll.h> struct vhost_work;struct vhost_task;typedef void (*vhost_work_fn_t)(struct vhost_work *work); #define VHOST_WORK_QUEUED 1struct vhost_work {	struct llist_node	node;	vhost_work_fn_t		fn;	unsigned long		flags;}; struct vhost_worker;struct vhost_dev;struct vhost_msg_node; struct vhost_worker_ops {	int (*create)(struct vhost_worker *worker, struct vhost_dev *dev,		      const char *name);	void (*stop)(struct vhost_worker *worker);	void (*wakeup)(struct vhost_worker *worker);}; struct vhost_worker {	struct task_struct *kthread_task;	struct vhost_task	*vtsk;	struct vhost_dev	*dev;	/* Used to serialize device wide flushing with worker swapping. */	struct mutex		mutex;	struct llist_head	work_list;	struct kcov_common_handle_id kcov_handle;	u32			id;	int			attachment_cnt;	bool			killed;	const struct vhost_worker_ops *ops;}; /* 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_entry_t	wait;	struct vhost_work	work;	__poll_t		mask;	struct vhost_dev	*dev;	struct vhost_virtqueue	*vq;}; void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,		     __poll_t mask, struct vhost_dev *dev,		     struct vhost_virtqueue *vq);int vhost_poll_start(struct vhost_poll *poll, struct file *file);void vhost_poll_stop(struct vhost_poll *poll);void vhost_poll_queue(struct vhost_poll *poll); void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);void vhost_dev_flush(struct vhost_dev *dev); struct vhost_log {	u64 addr;	u64 len;}; enum vhost_uaddr_type {	VHOST_ADDR_DESC = 0,	VHOST_ADDR_AVAIL = 1,	VHOST_ADDR_USED = 2,	VHOST_NUM_ADDRS = 3,}; struct vhost_vring_call {	struct eventfd_ctx *ctx;	struct irq_bypass_producer producer;}; /* The virtqueue structure describes a queue attached to a device. */struct vhost_virtqueue {	struct vhost_dev *dev;	struct vhost_worker __rcu *worker; 	/* The actual ring of buffers. */	struct mutex mutex;	unsigned int num;	vring_desc_t __user *desc;	vring_avail_t __user *avail;	vring_used_t __user *used;	const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS];	struct file *kick;	struct vhost_vring_call 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.	 * Values are limited to 0x7fff, and the high bit is used as	 * a wrap counter when using VIRTIO_F_RING_PACKED. */	u16 last_avail_idx;	/* Next avail ring head when VIRTIO_F_IN_ORDER is negoitated */	u16 next_avail_head; 	/* Caches available index value from user. */	u16 avail_idx; 	/* Last index we used.	 * Values are limited to 0x7fff, and the high bit is used as	 * a wrap counter when using VIRTIO_F_RING_PACKED. */	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 iotlb_iov[64];	struct iovec *indirect;	struct vring_used_elem *heads;	u16 *nheads;	/* Protected by virtqueue mutex. */	struct vhost_iotlb *umem;	struct vhost_iotlb *iotlb;	/* Protected by dev->iotlb_lock. */	struct vhost_msg_node *iotlb_miss;	void *private_data;	VIRTIO_DECLARE_FEATURES(acked_features);	u64 acked_backend_features;	/* Log write descriptors */	void __user *log_base;	struct vhost_log *log;	struct iovec log_iov[64]; 	/* 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_msg_node {  union {	  struct vhost_msg msg;	  struct vhost_msg_v2 msg_v2;  };  struct vhost_virtqueue *vq;  struct list_head node;}; struct vhost_dev {	struct mm_struct *mm;	struct mutex mutex;	struct vhost_virtqueue **vqs;	int nvqs;	struct eventfd_ctx *log_ctx;	struct vhost_iotlb *umem;	struct vhost_iotlb *iotlb;	spinlock_t iotlb_lock;	struct list_head read_list;	struct list_head pending_list;	wait_queue_head_t wait;	int iov_limit;	int weight;	int byte_weight;	struct xarray worker_xa;	bool use_worker;	/*	 * If fork_owner is true we use vhost_tasks to create	 * the worker so all settings/limits like cgroups, NPROC,	 * scheduler, etc are inherited from the owner. If false,	 * we use kthreads and only attach to the same cgroups	 * as the owner for compat with older kernels.	 * here we use true as default value.	 * The default value is set by fork_from_owner_default	 */	bool fork_owner;	int (*msg_handler)(struct vhost_dev *dev, u32 asid,			   struct vhost_iotlb_msg *msg);}; bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len);void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,		    int nvqs, int iov_limit, int weight, int byte_weight,		    bool use_worker,		    int (*msg_handler)(struct vhost_dev *dev, u32 asid,				       struct vhost_iotlb_msg *msg));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_iotlb *vhost_dev_reset_owner_prepare(void);void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *iotlb);void vhost_dev_cleanup(struct vhost_dev *);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, unsigned int ioctl, void __user *argp);long vhost_worker_ioctl(struct vhost_dev *dev, unsigned int ioctl,			void __user *argp);bool vhost_vq_access_ok(struct vhost_virtqueue *vq);bool vhost_log_access_ok(struct vhost_dev *);void vhost_clear_msg(struct vhost_dev *dev); int vhost_get_vq_desc(struct vhost_virtqueue *,		      struct iovec iov[], unsigned int iov_size,		      unsigned int *out_num, unsigned int *in_num,		      struct vhost_log *log, unsigned int *log_num); int vhost_get_vq_desc_n(struct vhost_virtqueue *vq,			struct iovec iov[], unsigned int iov_size,			unsigned int *out_num, unsigned int *in_num,			struct vhost_log *log, unsigned int *log_num,			unsigned int *ndesc); void vhost_discard_vq_desc(struct vhost_virtqueue *, int nbuf,			   unsigned int ndesc); bool vhost_vq_work_queue(struct vhost_virtqueue *vq, struct vhost_work *work);bool vhost_vq_has_work(struct vhost_virtqueue *vq);bool vhost_vq_is_setup(struct vhost_virtqueue *vq);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,		     u16 *nheads, 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, u16 *nheads,				 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,		    struct iovec *iov, int count);int vq_meta_prefetch(struct vhost_virtqueue *vq); struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);void vhost_enqueue_msg(struct vhost_dev *dev,		       struct list_head *head,		       struct vhost_msg_node *node);struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,					 struct list_head *head);void vhost_set_backend_features(struct vhost_dev *dev, u64 features); __poll_t vhost_chr_poll(struct file *file, struct vhost_dev *dev,			    poll_table *wait);ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to,			    int noblock);ssize_t vhost_chr_write_iter(struct vhost_dev *dev,			     struct iov_iter *from);void vhost_clear_device_iotlb(struct vhost_dev *d);int vhost_init_device_iotlb(struct vhost_dev *d); void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,			  struct vhost_iotlb_map *map); #define vq_err(vq, fmt, ...) do {                                  \		pr_debug(pr_fmt(fmt), ##__VA_ARGS__);       \		if ((vq)->error_ctx)                               \				eventfd_signal((vq)->error_ctx);\	} while (0) #define VHOST_FEATURES \	VIRTIO_F_NOTIFY_ON_EMPTY, \	VIRTIO_RING_F_INDIRECT_DESC, \	VIRTIO_RING_F_EVENT_IDX, \	VHOST_F_LOG_ALL, \	VIRTIO_F_ANY_LAYOUT, \	VIRTIO_F_VERSION_1 static inline u64 vhost_features_u64(const int *features, int size, int idx){	u64 res = 0; 	unrolled_count(VIRTIO_FEATURES_BITS)	for (int i = 0; i < size; ++i) {		int bit = features[i]; 		if (virtio_features_chk_bit(bit) && VIRTIO_U64(bit) == idx)			res |= VIRTIO_BIT(bit);	}	return res;} #define VHOST_FEATURES_U64(features, idx) \	vhost_features_u64(features, ARRAY_SIZE(features), idx) #define DEFINE_VHOST_FEATURES_ARRAY_ENTRY(idx, features) \	[idx] = VHOST_FEATURES_U64(features, idx), #define DEFINE_VHOST_FEATURES_ARRAY(array, features) \	u64 array[VIRTIO_FEATURES_U64S] = { \		UNROLL(VIRTIO_FEATURES_U64S, \		       DEFINE_VHOST_FEATURES_ARRAY_ENTRY, features) \	} /** * vhost_vq_set_backend - Set backend. * * @vq            Virtqueue. * @private_data  The private data. * * Context: Need to call with vq->mutex acquired. */static inline void vhost_vq_set_backend(struct vhost_virtqueue *vq,					void *private_data){	vq->private_data = private_data;} /** * vhost_vq_get_backend - Get backend. * * @vq            Virtqueue. * * Context: Need to call with vq->mutex acquired. * Return: Private data previously set with vhost_vq_set_backend. */static inline void *vhost_vq_get_backend(struct vhost_virtqueue *vq){	return vq->private_data;} static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit){	return virtio_features_test_bit(vq->acked_features_array, bit);} static inline bool vhost_backend_has_feature(struct vhost_virtqueue *vq, int bit){	return vq->acked_backend_features & (1ULL << bit);} #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACYstatic inline bool vhost_is_little_endian(struct vhost_virtqueue *vq){	return vq->is_le;}#elsestatic 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