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. */
118 u32 busyloop_timeout
;
122 struct vhost_memory
*memory
;
123 struct mm_struct
*mm
;
125 struct vhost_virtqueue
**vqs
;
127 struct file
*log_file
;
128 struct eventfd_ctx
*log_ctx
;
129 spinlock_t work_lock
;
130 struct list_head work_list
;
131 struct task_struct
*worker
;
134 void vhost_dev_init(struct vhost_dev
*, struct vhost_virtqueue
**vqs
, int nvqs
);
135 long vhost_dev_set_owner(struct vhost_dev
*dev
);
136 bool vhost_dev_has_owner(struct vhost_dev
*dev
);
137 long vhost_dev_check_owner(struct vhost_dev
*);
138 struct vhost_memory
*vhost_dev_reset_owner_prepare(void);
139 void vhost_dev_reset_owner(struct vhost_dev
*, struct vhost_memory
*);
140 void vhost_dev_cleanup(struct vhost_dev
*, bool locked
);
141 void vhost_dev_stop(struct vhost_dev
*);
142 long vhost_dev_ioctl(struct vhost_dev
*, unsigned int ioctl
, void __user
*argp
);
143 long vhost_vring_ioctl(struct vhost_dev
*d
, int ioctl
, void __user
*argp
);
144 int vhost_vq_access_ok(struct vhost_virtqueue
*vq
);
145 int vhost_log_access_ok(struct vhost_dev
*);
147 int vhost_get_vq_desc(struct vhost_virtqueue
*,
148 struct iovec iov
[], unsigned int iov_count
,
149 unsigned int *out_num
, unsigned int *in_num
,
150 struct vhost_log
*log
, unsigned int *log_num
);
151 void vhost_discard_vq_desc(struct vhost_virtqueue
*, int n
);
153 int vhost_vq_init_access(struct vhost_virtqueue
*);
154 int vhost_add_used(struct vhost_virtqueue
*, unsigned int head
, int len
);
155 int vhost_add_used_n(struct vhost_virtqueue
*, struct vring_used_elem
*heads
,
157 void vhost_add_used_and_signal(struct vhost_dev
*, struct vhost_virtqueue
*,
158 unsigned int id
, int len
);
159 void vhost_add_used_and_signal_n(struct vhost_dev
*, struct vhost_virtqueue
*,
160 struct vring_used_elem
*heads
, unsigned count
);
161 void vhost_signal(struct vhost_dev
*, struct vhost_virtqueue
*);
162 void vhost_disable_notify(struct vhost_dev
*, struct vhost_virtqueue
*);
163 bool vhost_vq_avail_empty(struct vhost_dev
*, struct vhost_virtqueue
*);
164 bool vhost_enable_notify(struct vhost_dev
*, struct vhost_virtqueue
*);
166 int vhost_log_write(struct vhost_virtqueue
*vq
, struct vhost_log
*log
,
167 unsigned int log_num
, u64 len
);
169 #define vq_err(vq, fmt, ...) do { \
170 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
171 if ((vq)->error_ctx) \
172 eventfd_signal((vq)->error_ctx, 1);\
176 VHOST_FEATURES
= (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY
) |
177 (1ULL << VIRTIO_RING_F_INDIRECT_DESC
) |
178 (1ULL << VIRTIO_RING_F_EVENT_IDX
) |
179 (1ULL << VHOST_F_LOG_ALL
) |
180 (1ULL << VIRTIO_F_ANY_LAYOUT
) |
181 (1ULL << VIRTIO_F_VERSION_1
)
184 static inline bool vhost_has_feature(struct vhost_virtqueue
*vq
, int bit
)
186 return vq
->acked_features
& (1ULL << bit
);
189 #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
190 static inline bool vhost_is_little_endian(struct vhost_virtqueue
*vq
)
195 static inline bool vhost_is_little_endian(struct vhost_virtqueue
*vq
)
197 return virtio_legacy_is_little_endian() || vq
->is_le
;
201 /* Memory accessors */
202 static inline u16
vhost16_to_cpu(struct vhost_virtqueue
*vq
, __virtio16 val
)
204 return __virtio16_to_cpu(vhost_is_little_endian(vq
), val
);
207 static inline __virtio16
cpu_to_vhost16(struct vhost_virtqueue
*vq
, u16 val
)
209 return __cpu_to_virtio16(vhost_is_little_endian(vq
), val
);
212 static inline u32
vhost32_to_cpu(struct vhost_virtqueue
*vq
, __virtio32 val
)
214 return __virtio32_to_cpu(vhost_is_little_endian(vq
), val
);
217 static inline __virtio32
cpu_to_vhost32(struct vhost_virtqueue
*vq
, u32 val
)
219 return __cpu_to_virtio32(vhost_is_little_endian(vq
), val
);
222 static inline u64
vhost64_to_cpu(struct vhost_virtqueue
*vq
, __virtio64 val
)
224 return __virtio64_to_cpu(vhost_is_little_endian(vq
), val
);
227 static inline __virtio64
cpu_to_vhost64(struct vhost_virtqueue
*vq
, u64 val
)
229 return __cpu_to_virtio64(vhost_is_little_endian(vq
), val
);