4 #include <linux/eventfd.h>
5 #include <linux/vhost.h>
7 #include <linux/mutex.h>
8 #include <linux/poll.h>
9 #include <linux/file.h>
10 #include <linux/uio.h>
11 #include <linux/virtio_config.h>
12 #include <linux/virtio_ring.h>
13 #include <linux/atomic.h>
16 typedef void (*vhost_work_fn_t
)(struct vhost_work
*work
);
19 struct list_head node
;
21 wait_queue_head_t done
;
27 /* Poll a file (eventfd or socket) */
28 /* Note: there's nothing vhost specific about this structure. */
31 wait_queue_head_t
*wqh
;
33 struct vhost_work work
;
35 struct vhost_dev
*dev
;
38 void vhost_work_init(struct vhost_work
*work
, vhost_work_fn_t fn
);
39 void vhost_work_queue(struct vhost_dev
*dev
, struct vhost_work
*work
);
40 bool vhost_has_work(struct vhost_dev
*dev
);
42 void vhost_poll_init(struct vhost_poll
*poll
, vhost_work_fn_t fn
,
43 unsigned long mask
, struct vhost_dev
*dev
);
44 int vhost_poll_start(struct vhost_poll
*poll
, struct file
*file
);
45 void vhost_poll_stop(struct vhost_poll
*poll
);
46 void vhost_poll_flush(struct vhost_poll
*poll
);
47 void vhost_poll_queue(struct vhost_poll
*poll
);
48 void vhost_work_flush(struct vhost_dev
*dev
, struct vhost_work
*work
);
49 long vhost_vring_ioctl(struct vhost_dev
*d
, int ioctl
, void __user
*argp
);
56 /* The virtqueue structure describes a queue attached to a device. */
57 struct vhost_virtqueue
{
58 struct vhost_dev
*dev
;
60 /* The actual ring of buffers. */
63 struct vring_desc __user
*desc
;
64 struct vring_avail __user
*avail
;
65 struct vring_used __user
*used
;
69 struct eventfd_ctx
*call_ctx
;
70 struct eventfd_ctx
*error_ctx
;
71 struct eventfd_ctx
*log_ctx
;
73 struct vhost_poll poll
;
75 /* The routine to call when the Guest pings us, or timeout. */
76 vhost_work_fn_t handle_kick
;
78 /* Last available index we saw. */
81 /* Caches available index value from user. */
84 /* Last index we used. */
90 /* Last used index value we have signalled on */
93 /* Last used index value we have signalled on */
94 bool signalled_used_valid
;
96 /* Log writes to used structure. */
100 struct iovec iov
[UIO_MAXIOV
];
101 struct iovec
*indirect
;
102 struct vring_used_elem
*heads
;
103 /* Protected by virtqueue mutex. */
104 struct vhost_memory
*memory
;
107 /* Log write descriptors */
108 void __user
*log_base
;
109 struct vhost_log
*log
;
111 /* Ring endianness. Defaults to legacy native endianness.
112 * Set to true when starting a modern virtio device. */
114 #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
115 /* Ring endianness requested by userspace for cross-endian support. */
121 struct vhost_memory
*memory
;
122 struct mm_struct
*mm
;
124 struct vhost_virtqueue
**vqs
;
126 struct file
*log_file
;
127 struct eventfd_ctx
*log_ctx
;
128 spinlock_t work_lock
;
129 struct list_head work_list
;
130 struct task_struct
*worker
;
133 void vhost_dev_init(struct vhost_dev
*, struct vhost_virtqueue
**vqs
, int nvqs
);
134 long vhost_dev_set_owner(struct vhost_dev
*dev
);
135 bool vhost_dev_has_owner(struct vhost_dev
*dev
);
136 long vhost_dev_check_owner(struct vhost_dev
*);
137 struct vhost_memory
*vhost_dev_reset_owner_prepare(void);
138 void vhost_dev_reset_owner(struct vhost_dev
*, struct vhost_memory
*);
139 void vhost_dev_cleanup(struct vhost_dev
*, bool locked
);
140 void vhost_dev_stop(struct vhost_dev
*);
141 long vhost_dev_ioctl(struct vhost_dev
*, unsigned int ioctl
, void __user
*argp
);
142 long vhost_vring_ioctl(struct vhost_dev
*d
, int ioctl
, void __user
*argp
);
143 int vhost_vq_access_ok(struct vhost_virtqueue
*vq
);
144 int vhost_log_access_ok(struct vhost_dev
*);
146 int vhost_get_vq_desc(struct vhost_virtqueue
*,
147 struct iovec iov
[], unsigned int iov_count
,
148 unsigned int *out_num
, unsigned int *in_num
,
149 struct vhost_log
*log
, unsigned int *log_num
);
150 void vhost_discard_vq_desc(struct vhost_virtqueue
*, int n
);
152 int vhost_vq_init_access(struct vhost_virtqueue
*);
153 int vhost_add_used(struct vhost_virtqueue
*, unsigned int head
, int len
);
154 int vhost_add_used_n(struct vhost_virtqueue
*, struct vring_used_elem
*heads
,
156 void vhost_add_used_and_signal(struct vhost_dev
*, struct vhost_virtqueue
*,
157 unsigned int id
, int len
);
158 void vhost_add_used_and_signal_n(struct vhost_dev
*, struct vhost_virtqueue
*,
159 struct vring_used_elem
*heads
, unsigned count
);
160 void vhost_signal(struct vhost_dev
*, struct vhost_virtqueue
*);
161 void vhost_disable_notify(struct vhost_dev
*, struct vhost_virtqueue
*);
162 bool vhost_enable_notify(struct vhost_dev
*, struct vhost_virtqueue
*);
164 int vhost_log_write(struct vhost_virtqueue
*vq
, struct vhost_log
*log
,
165 unsigned int log_num
, u64 len
);
167 #define vq_err(vq, fmt, ...) do { \
168 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
169 if ((vq)->error_ctx) \
170 eventfd_signal((vq)->error_ctx, 1);\
174 VHOST_FEATURES
= (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY
) |
175 (1ULL << VIRTIO_RING_F_INDIRECT_DESC
) |
176 (1ULL << VIRTIO_RING_F_EVENT_IDX
) |
177 (1ULL << VHOST_F_LOG_ALL
) |
178 (1ULL << VIRTIO_F_ANY_LAYOUT
) |
179 (1ULL << VIRTIO_F_VERSION_1
)
182 static inline bool vhost_has_feature(struct vhost_virtqueue
*vq
, int bit
)
184 return vq
->acked_features
& (1ULL << bit
);
187 #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
188 static inline bool vhost_is_little_endian(struct vhost_virtqueue
*vq
)
193 static inline bool vhost_is_little_endian(struct vhost_virtqueue
*vq
)
195 return virtio_legacy_is_little_endian() || vq
->is_le
;
199 /* Memory accessors */
200 static inline u16
vhost16_to_cpu(struct vhost_virtqueue
*vq
, __virtio16 val
)
202 return __virtio16_to_cpu(vhost_is_little_endian(vq
), val
);
205 static inline __virtio16
cpu_to_vhost16(struct vhost_virtqueue
*vq
, u16 val
)
207 return __cpu_to_virtio16(vhost_is_little_endian(vq
), val
);
210 static inline u32
vhost32_to_cpu(struct vhost_virtqueue
*vq
, __virtio32 val
)
212 return __virtio32_to_cpu(vhost_is_little_endian(vq
), val
);
215 static inline __virtio32
cpu_to_vhost32(struct vhost_virtqueue
*vq
, u32 val
)
217 return __cpu_to_virtio32(vhost_is_little_endian(vq
), val
);
220 static inline u64
vhost64_to_cpu(struct vhost_virtqueue
*vq
, __virtio64 val
)
222 return __virtio64_to_cpu(vhost_is_little_endian(vq
), val
);
225 static inline __virtio64
cpu_to_vhost64(struct vhost_virtqueue
*vq
, u64 val
)
227 return __cpu_to_virtio64(vhost_is_little_endian(vq
), val
);