1
2#ifndef _VHOST_H
3#define _VHOST_H
4
5#include <linux/eventfd.h>
6#include <linux/vhost.h>
7#include <linux/mm.h>
8#include <linux/mutex.h>
9#include <linux/poll.h>
10#include <linux/file.h>
11#include <linux/uio.h>
12#include <linux/virtio_config.h>
13#include <linux/virtio_ring.h>
14#include <linux/atomic.h>
15#include <linux/vhost_iotlb.h>
16#include <linux/irqbypass.h>
17
18struct vhost_work;
19typedef void (*vhost_work_fn_t)(struct vhost_work *work);
20
21#define VHOST_WORK_QUEUED 1
22struct vhost_work {
23 struct llist_node node;
24 vhost_work_fn_t fn;
25 unsigned long flags;
26};
27
28
29
30struct vhost_poll {
31 poll_table table;
32 wait_queue_head_t *wqh;
33 wait_queue_entry_t wait;
34 struct vhost_work work;
35 __poll_t mask;
36 struct vhost_dev *dev;
37};
38
39void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn);
40void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work);
41bool vhost_has_work(struct vhost_dev *dev);
42
43void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
44 __poll_t mask, struct vhost_dev *dev);
45int vhost_poll_start(struct vhost_poll *poll, struct file *file);
46void vhost_poll_stop(struct vhost_poll *poll);
47void vhost_poll_flush(struct vhost_poll *poll);
48void vhost_poll_queue(struct vhost_poll *poll);
49void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work);
50long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp);
51
52struct vhost_log {
53 u64 addr;
54 u64 len;
55};
56
57enum vhost_uaddr_type {
58 VHOST_ADDR_DESC = 0,
59 VHOST_ADDR_AVAIL = 1,
60 VHOST_ADDR_USED = 2,
61 VHOST_NUM_ADDRS = 3,
62};
63
64struct vhost_vring_call {
65 struct eventfd_ctx *ctx;
66 struct irq_bypass_producer producer;
67};
68
69
70struct vhost_virtqueue {
71 struct vhost_dev *dev;
72
73
74 struct mutex mutex;
75 unsigned int num;
76 struct vring_desc __user *desc;
77 struct vring_avail __user *avail;
78 struct vring_used __user *used;
79 const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS];
80 struct file *kick;
81 struct vhost_vring_call call_ctx;
82 struct eventfd_ctx *error_ctx;
83 struct eventfd_ctx *log_ctx;
84
85 struct vhost_poll poll;
86
87
88 vhost_work_fn_t handle_kick;
89
90
91 u16 last_avail_idx;
92
93
94 u16 avail_idx;
95
96
97 u16 last_used_idx;
98
99
100 u16 used_flags;
101
102
103 u16 signalled_used;
104
105
106 bool signalled_used_valid;
107
108
109 bool log_used;
110 u64 log_addr;
111
112 struct iovec iov[UIO_MAXIOV];
113 struct iovec iotlb_iov[64];
114 struct iovec *indirect;
115 struct vring_used_elem *heads;
116
117 struct vhost_iotlb *umem;
118 struct vhost_iotlb *iotlb;
119 void *private_data;
120 u64 acked_features;
121 u64 acked_backend_features;
122
123 void __user *log_base;
124 struct vhost_log *log;
125
126
127
128 bool is_le;
129#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
130
131 bool user_be;
132#endif
133 u32 busyloop_timeout;
134};
135
136struct vhost_msg_node {
137 union {
138 struct vhost_msg msg;
139 struct vhost_msg_v2 msg_v2;
140 };
141 struct vhost_virtqueue *vq;
142 struct list_head node;
143};
144
145struct vhost_dev {
146 struct mm_struct *mm;
147 struct mutex mutex;
148 struct vhost_virtqueue **vqs;
149 int nvqs;
150 struct eventfd_ctx *log_ctx;
151 struct llist_head work_list;
152 struct task_struct *worker;
153 struct vhost_iotlb *umem;
154 struct vhost_iotlb *iotlb;
155 spinlock_t iotlb_lock;
156 struct list_head read_list;
157 struct list_head pending_list;
158 wait_queue_head_t wait;
159 int iov_limit;
160 int weight;
161 int byte_weight;
162 bool use_worker;
163 int (*msg_handler)(struct vhost_dev *dev,
164 struct vhost_iotlb_msg *msg);
165};
166
167bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len);
168void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,
169 int nvqs, int iov_limit, int weight, int byte_weight,
170 bool use_worker,
171 int (*msg_handler)(struct vhost_dev *dev,
172 struct vhost_iotlb_msg *msg));
173long vhost_dev_set_owner(struct vhost_dev *dev);
174bool vhost_dev_has_owner(struct vhost_dev *dev);
175long vhost_dev_check_owner(struct vhost_dev *);
176struct vhost_iotlb *vhost_dev_reset_owner_prepare(void);
177void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_iotlb *iotlb);
178void vhost_dev_cleanup(struct vhost_dev *);
179void vhost_dev_stop(struct vhost_dev *);
180long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp);
181long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp);
182bool vhost_vq_access_ok(struct vhost_virtqueue *vq);
183bool vhost_log_access_ok(struct vhost_dev *);
184
185int vhost_get_vq_desc(struct vhost_virtqueue *,
186 struct iovec iov[], unsigned int iov_count,
187 unsigned int *out_num, unsigned int *in_num,
188 struct vhost_log *log, unsigned int *log_num);
189void vhost_discard_vq_desc(struct vhost_virtqueue *, int n);
190
191int vhost_vq_init_access(struct vhost_virtqueue *);
192int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len);
193int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads,
194 unsigned count);
195void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *,
196 unsigned int id, int len);
197void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
198 struct vring_used_elem *heads, unsigned count);
199void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
200void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
201bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *);
202bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
203
204int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
205 unsigned int log_num, u64 len,
206 struct iovec *iov, int count);
207int vq_meta_prefetch(struct vhost_virtqueue *vq);
208
209struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type);
210void vhost_enqueue_msg(struct vhost_dev *dev,
211 struct list_head *head,
212 struct vhost_msg_node *node);
213struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev,
214 struct list_head *head);
215void vhost_set_backend_features(struct vhost_dev *dev, u64 features);
216
217__poll_t vhost_chr_poll(struct file *file, struct vhost_dev *dev,
218 poll_table *wait);
219ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to,
220 int noblock);
221ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
222 struct iov_iter *from);
223int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled);
224
225void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
226 struct vhost_iotlb_map *map);
227
228#define vq_err(vq, fmt, ...) do { \
229 pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
230 if ((vq)->error_ctx) \
231 eventfd_signal((vq)->error_ctx, 1);\
232 } while (0)
233
234enum {
235 VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
236 (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
237 (1ULL << VIRTIO_RING_F_EVENT_IDX) |
238 (1ULL << VHOST_F_LOG_ALL) |
239 (1ULL << VIRTIO_F_ANY_LAYOUT) |
240 (1ULL << VIRTIO_F_VERSION_1)
241};
242
243static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit)
244{
245 return vq->acked_features & (1ULL << bit);
246}
247
248static inline bool vhost_backend_has_feature(struct vhost_virtqueue *vq, int bit)
249{
250 return vq->acked_backend_features & (1ULL << bit);
251}
252
253#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
254static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
255{
256 return vq->is_le;
257}
258#else
259static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq)
260{
261 return virtio_legacy_is_little_endian() || vq->is_le;
262}
263#endif
264
265
266static inline u16 vhost16_to_cpu(struct vhost_virtqueue *vq, __virtio16 val)
267{
268 return __virtio16_to_cpu(vhost_is_little_endian(vq), val);
269}
270
271static inline __virtio16 cpu_to_vhost16(struct vhost_virtqueue *vq, u16 val)
272{
273 return __cpu_to_virtio16(vhost_is_little_endian(vq), val);
274}
275
276static inline u32 vhost32_to_cpu(struct vhost_virtqueue *vq, __virtio32 val)
277{
278 return __virtio32_to_cpu(vhost_is_little_endian(vq), val);
279}
280
281static inline __virtio32 cpu_to_vhost32(struct vhost_virtqueue *vq, u32 val)
282{
283 return __cpu_to_virtio32(vhost_is_little_endian(vq), val);
284}
285
286static inline u64 vhost64_to_cpu(struct vhost_virtqueue *vq, __virtio64 val)
287{
288 return __virtio64_to_cpu(vhost_is_little_endian(vq), val);
289}
290
291static inline __virtio64 cpu_to_vhost64(struct vhost_virtqueue *vq, u64 val)
292{
293 return __cpu_to_virtio64(vhost_is_little_endian(vq), val);
294}
295#endif
296