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11#ifndef _LINUX_VRINGH_H
12#define _LINUX_VRINGH_H
13#include <uapi/linux/virtio_ring.h>
14#include <linux/virtio_byteorder.h>
15#include <linux/uio.h>
16#include <linux/slab.h>
17#if IS_REACHABLE(CONFIG_VHOST_IOTLB)
18#include <linux/dma-direction.h>
19#include <linux/vhost_iotlb.h>
20#endif
21#include <asm/barrier.h>
22
23
24struct vringh {
25
26 bool little_endian;
27
28
29 bool event_indices;
30
31
32 bool weak_barriers;
33
34
35 u16 last_avail_idx;
36
37
38 u16 last_used_idx;
39
40
41 u32 completed;
42
43
44 struct vring vring;
45
46
47 struct vhost_iotlb *iotlb;
48
49
50 void (*notify)(struct vringh *);
51};
52
53
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60
61
62
63
64struct virtio_device;
65typedef void vrh_callback_t(struct virtio_device *, struct vringh *);
66struct vringh_config_ops {
67 int (*find_vrhs)(struct virtio_device *vdev, unsigned nhvrs,
68 struct vringh *vrhs[], vrh_callback_t *callbacks[]);
69 void (*del_vrhs)(struct virtio_device *vdev);
70};
71
72
73struct vringh_range {
74 u64 start, end_incl;
75 u64 offset;
76};
77
78
79
80
81
82
83
84struct vringh_iov {
85 struct iovec *iov;
86 size_t consumed;
87 unsigned i, used, max_num;
88};
89
90
91
92
93
94
95
96struct vringh_kiov {
97 struct kvec *iov;
98 size_t consumed;
99 unsigned i, used, max_num;
100};
101
102
103#define VRINGH_IOV_ALLOCATED 0x8000000
104
105
106int vringh_init_user(struct vringh *vrh, u64 features,
107 unsigned int num, bool weak_barriers,
108 vring_desc_t __user *desc,
109 vring_avail_t __user *avail,
110 vring_used_t __user *used);
111
112static inline void vringh_iov_init(struct vringh_iov *iov,
113 struct iovec *iovec, unsigned num)
114{
115 iov->used = iov->i = 0;
116 iov->consumed = 0;
117 iov->max_num = num;
118 iov->iov = iovec;
119}
120
121static inline void vringh_iov_reset(struct vringh_iov *iov)
122{
123 iov->iov[iov->i].iov_len += iov->consumed;
124 iov->iov[iov->i].iov_base -= iov->consumed;
125 iov->consumed = 0;
126 iov->i = 0;
127}
128
129static inline void vringh_iov_cleanup(struct vringh_iov *iov)
130{
131 if (iov->max_num & VRINGH_IOV_ALLOCATED)
132 kfree(iov->iov);
133 iov->max_num = iov->used = iov->i = iov->consumed = 0;
134 iov->iov = NULL;
135}
136
137
138int vringh_getdesc_user(struct vringh *vrh,
139 struct vringh_iov *riov,
140 struct vringh_iov *wiov,
141 bool (*getrange)(struct vringh *vrh,
142 u64 addr, struct vringh_range *r),
143 u16 *head);
144
145
146ssize_t vringh_iov_pull_user(struct vringh_iov *riov, void *dst, size_t len);
147
148
149ssize_t vringh_iov_push_user(struct vringh_iov *wiov,
150 const void *src, size_t len);
151
152
153int vringh_complete_user(struct vringh *vrh, u16 head, u32 len);
154int vringh_complete_multi_user(struct vringh *vrh,
155 const struct vring_used_elem used[],
156 unsigned num_used);
157
158
159void vringh_abandon_user(struct vringh *vrh, unsigned int num);
160
161
162int vringh_need_notify_user(struct vringh *vrh);
163
164bool vringh_notify_enable_user(struct vringh *vrh);
165void vringh_notify_disable_user(struct vringh *vrh);
166
167
168int vringh_init_kern(struct vringh *vrh, u64 features,
169 unsigned int num, bool weak_barriers,
170 struct vring_desc *desc,
171 struct vring_avail *avail,
172 struct vring_used *used);
173
174static inline void vringh_kiov_init(struct vringh_kiov *kiov,
175 struct kvec *kvec, unsigned num)
176{
177 kiov->used = kiov->i = 0;
178 kiov->consumed = 0;
179 kiov->max_num = num;
180 kiov->iov = kvec;
181}
182
183static inline void vringh_kiov_reset(struct vringh_kiov *kiov)
184{
185 kiov->iov[kiov->i].iov_len += kiov->consumed;
186 kiov->iov[kiov->i].iov_base -= kiov->consumed;
187 kiov->consumed = 0;
188 kiov->i = 0;
189}
190
191static inline void vringh_kiov_cleanup(struct vringh_kiov *kiov)
192{
193 if (kiov->max_num & VRINGH_IOV_ALLOCATED)
194 kfree(kiov->iov);
195 kiov->max_num = kiov->used = kiov->i = kiov->consumed = 0;
196 kiov->iov = NULL;
197}
198
199int vringh_getdesc_kern(struct vringh *vrh,
200 struct vringh_kiov *riov,
201 struct vringh_kiov *wiov,
202 u16 *head,
203 gfp_t gfp);
204
205ssize_t vringh_iov_pull_kern(struct vringh_kiov *riov, void *dst, size_t len);
206ssize_t vringh_iov_push_kern(struct vringh_kiov *wiov,
207 const void *src, size_t len);
208void vringh_abandon_kern(struct vringh *vrh, unsigned int num);
209int vringh_complete_kern(struct vringh *vrh, u16 head, u32 len);
210
211bool vringh_notify_enable_kern(struct vringh *vrh);
212void vringh_notify_disable_kern(struct vringh *vrh);
213
214int vringh_need_notify_kern(struct vringh *vrh);
215
216
217static inline void vringh_notify(struct vringh *vrh)
218{
219 if (vrh->notify)
220 vrh->notify(vrh);
221}
222
223static inline bool vringh_is_little_endian(const struct vringh *vrh)
224{
225 return vrh->little_endian ||
226 virtio_legacy_is_little_endian();
227}
228
229static inline u16 vringh16_to_cpu(const struct vringh *vrh, __virtio16 val)
230{
231 return __virtio16_to_cpu(vringh_is_little_endian(vrh), val);
232}
233
234static inline __virtio16 cpu_to_vringh16(const struct vringh *vrh, u16 val)
235{
236 return __cpu_to_virtio16(vringh_is_little_endian(vrh), val);
237}
238
239static inline u32 vringh32_to_cpu(const struct vringh *vrh, __virtio32 val)
240{
241 return __virtio32_to_cpu(vringh_is_little_endian(vrh), val);
242}
243
244static inline __virtio32 cpu_to_vringh32(const struct vringh *vrh, u32 val)
245{
246 return __cpu_to_virtio32(vringh_is_little_endian(vrh), val);
247}
248
249static inline u64 vringh64_to_cpu(const struct vringh *vrh, __virtio64 val)
250{
251 return __virtio64_to_cpu(vringh_is_little_endian(vrh), val);
252}
253
254static inline __virtio64 cpu_to_vringh64(const struct vringh *vrh, u64 val)
255{
256 return __cpu_to_virtio64(vringh_is_little_endian(vrh), val);
257}
258
259#if IS_REACHABLE(CONFIG_VHOST_IOTLB)
260
261void vringh_set_iotlb(struct vringh *vrh, struct vhost_iotlb *iotlb);
262
263int vringh_init_iotlb(struct vringh *vrh, u64 features,
264 unsigned int num, bool weak_barriers,
265 struct vring_desc *desc,
266 struct vring_avail *avail,
267 struct vring_used *used);
268
269int vringh_getdesc_iotlb(struct vringh *vrh,
270 struct vringh_kiov *riov,
271 struct vringh_kiov *wiov,
272 u16 *head,
273 gfp_t gfp);
274
275ssize_t vringh_iov_pull_iotlb(struct vringh *vrh,
276 struct vringh_kiov *riov,
277 void *dst, size_t len);
278ssize_t vringh_iov_push_iotlb(struct vringh *vrh,
279 struct vringh_kiov *wiov,
280 const void *src, size_t len);
281
282void vringh_abandon_iotlb(struct vringh *vrh, unsigned int num);
283
284int vringh_complete_iotlb(struct vringh *vrh, u16 head, u32 len);
285
286bool vringh_notify_enable_iotlb(struct vringh *vrh);
287void vringh_notify_disable_iotlb(struct vringh *vrh);
288
289int vringh_need_notify_iotlb(struct vringh *vrh);
290
291#endif
292
293#endif
294