xref: /openbsd/sys/dev/pv/virtiovar.h (revision 771fbea0)
1 /*	$OpenBSD: virtiovar.h,v 1.14 2019/05/26 15:22:31 sf Exp $	*/
2 /*	$NetBSD: virtiovar.h,v 1.1 2011/10/30 12:12:21 hannken Exp $	*/
3 
4 /*
5  * Copyright (c) 2012 Stefan Fritsch.
6  * Copyright (c) 2010 Minoura Makoto.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 /*
31  * Part of the file derived from `Virtio PCI Card Specification v0.8.6 DRAFT'
32  * Appendix A.
33  */
34 /* An interface for efficient virtio implementation.
35  *
36  * This header is BSD licensed so anyone can use the definitions
37  * to implement compatible drivers/servers.
38  *
39  * Copyright 2007, 2009, IBM Corporation
40  * All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of IBM nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  */
65 
66 
67 #ifndef _DEV_PV_VIRTIOVAR_H_
68 #define	_DEV_PV_VIRTIOVAR_H_
69 
70 #include <sys/param.h>
71 #include <sys/queue.h>
72 #include <sys/device.h>
73 #include <sys/mutex.h>
74 #include <machine/bus.h>
75 
76 #include <dev/pv/virtioreg.h>
77 
78 #ifndef VIRTIO_DEBUG
79 #define VIRTIO_DEBUG		0
80 #endif
81 
82 /* flags for config(8) */
83 #define VIRTIO_CF_NO_INDIRECT		1
84 #define VIRTIO_CF_NO_EVENT_IDX		2
85 #define VIRTIO_CF_PREFER_VERSION_1	4
86 #define VIRTIO_CF_NO_VERSION_1		8
87 
88 struct vq_entry {
89 	SLIST_ENTRY(vq_entry)	 qe_list;	/* free list */
90 	uint16_t		 qe_index;	/* index in vq_desc array */
91 
92 	/* The following are used only in the `head' entry */
93 	int16_t			 qe_next;	/* next enq slot */
94 	int16_t			 qe_indirect;	/* 1 if using indirect */
95 	int16_t			 qe_vr_index;	/* index in sc_reqs array */
96 	struct vring_desc	*qe_desc_base;	/* pointer to vd array */
97 };
98 
99 struct virtqueue {
100 	struct virtio_softc	*vq_owner;
101 	unsigned int		vq_num;  /* queue size (# of entries) */
102 	unsigned int		vq_mask; /* (1 << vq_num - 1) */
103 	int			vq_index; /* queue number (0, 1, ...) */
104 
105 	/* vring pointers (KVA) */
106 	struct vring_desc	*vq_desc;
107 	struct vring_avail	*vq_avail;
108 	struct vring_used	*vq_used;
109 	void			*vq_indirect;
110 
111 	/* virtqueue allocation info */
112 	void			*vq_vaddr;
113 	int			vq_availoffset;
114 	int			vq_usedoffset;
115 	int			vq_indirectoffset;
116 	bus_dma_segment_t	vq_segs[1];
117 	unsigned int		vq_bytesize;
118 	bus_dmamap_t		vq_dmamap;
119 
120 	int			vq_maxnsegs;
121 
122 	/* free entry management */
123 	struct vq_entry		*vq_entries;
124 	SLIST_HEAD(, vq_entry) vq_freelist;
125 	struct mutex		*vq_freelist_lock;
126 
127 	/* enqueue/dequeue status */
128 	uint16_t		vq_avail_idx;
129 	uint16_t		vq_used_idx;
130 	int			vq_queued;
131 	struct mutex		*vq_aring_lock;
132 	struct mutex		*vq_uring_lock;
133 
134 	/* interrupt handler */
135 	int			(*vq_done)(struct virtqueue*);
136 	/* 1.x only: offset for notify address calculation */
137 	uint32_t		vq_notify_off;
138 };
139 
140 struct virtio_feature_name {
141 	uint32_t	 bit;
142 	const char	*name;
143 };
144 
145 struct virtio_ops {
146 	void		(*kick)(struct virtio_softc *, uint16_t);
147 	uint8_t		(*read_dev_cfg_1)(struct virtio_softc *, int);
148 	uint16_t	(*read_dev_cfg_2)(struct virtio_softc *, int);
149 	uint32_t	(*read_dev_cfg_4)(struct virtio_softc *, int);
150 	uint64_t	(*read_dev_cfg_8)(struct virtio_softc *, int);
151 	void		(*write_dev_cfg_1)(struct virtio_softc *, int, uint8_t);
152 	void		(*write_dev_cfg_2)(struct virtio_softc *, int, uint16_t);
153 	void		(*write_dev_cfg_4)(struct virtio_softc *, int, uint32_t);
154 	void		(*write_dev_cfg_8)(struct virtio_softc *, int, uint64_t);
155 	uint16_t	(*read_queue_size)(struct virtio_softc *, uint16_t);
156 	void		(*setup_queue)(struct virtio_softc *, struct virtqueue *, uint64_t);
157 	void		(*set_status)(struct virtio_softc *, int);
158 	int		(*neg_features)(struct virtio_softc *, const struct virtio_feature_name *);
159 	int		(*poll_intr)(void *);
160 };
161 
162 #define VIRTIO_CHILD_ERROR	((void*)1)
163 
164 struct virtio_softc {
165 	struct device		 sc_dev;
166 	bus_dma_tag_t		 sc_dmat;	/* set by transport */
167 	struct virtio_ops	*sc_ops;	/* set by transport */
168 
169 	int			 sc_ipl;		/* set by child */
170 
171 	uint64_t		 sc_driver_features;
172 	uint64_t		 sc_active_features;
173 	int			 sc_indirect;
174 	int			 sc_version_1;
175 
176 	int			 sc_nvqs;	/* set by child */
177 	struct virtqueue	*sc_vqs;	/* set by child */
178 
179 	int			 sc_childdevid;	/* set by transport */
180 	struct device		*sc_child;	/* set by child,
181 						 * VIRTIO_CHILD_ERROR on error
182 						 */
183 	int			(*sc_config_change)(struct virtio_softc*);
184 						/* set by child */
185 };
186 
187 /* public interface */
188 #define	virtio_read_device_config_1(sc, o)	(sc)->sc_ops->read_dev_cfg_1(sc, o)
189 #define	virtio_read_device_config_2(sc, o)	(sc)->sc_ops->read_dev_cfg_2(sc, o)
190 #define	virtio_read_device_config_4(sc, o)	(sc)->sc_ops->read_dev_cfg_4(sc, o)
191 #define	virtio_read_device_config_8(sc, o)	(sc)->sc_ops->read_dev_cfg_8(sc, o)
192 #define	virtio_write_device_config_1(sc, o, v)	(sc)->sc_ops->write_dev_cfg_1(sc, o, v)
193 #define	virtio_write_device_config_2(sc, o, v)	(sc)->sc_ops->write_dev_cfg_2(sc, o, v)
194 #define	virtio_write_device_config_4(sc, o, v)	(sc)->sc_ops->write_dev_cfg_4(sc, o, v)
195 #define	virtio_write_device_config_8(sc, o, v)	(sc)->sc_ops->write_dev_cfg_8(sc, o, v)
196 #define	virtio_read_queue_size(sc, i)		(sc)->sc_ops->read_queue_size(sc, i)
197 #define	virtio_setup_queue(sc, i, v)		(sc)->sc_ops->setup_queue(sc, i, v)
198 #define	virtio_negotiate_features(sc, n)	(sc)->sc_ops->neg_features(sc, n)
199 #define	virtio_poll_intr(sc)			(sc)->sc_ops->poll_intr(sc)
200 
201 /* only for transport drivers */
202 #define	virtio_set_status(sc, i)		(sc)->sc_ops->set_status(sc, i)
203 #define	virtio_device_reset(sc)			virtio_set_status((sc), 0)
204 
205 static inline int
206 virtio_has_feature(struct virtio_softc *sc, unsigned int fbit)
207 {
208 	if (sc->sc_active_features & fbit)
209 		return 1;
210 	return 0;
211 }
212 
213 int virtio_alloc_vq(struct virtio_softc*, struct virtqueue*, int, int, int,
214 		    const char*);
215 int virtio_free_vq(struct virtio_softc*, struct virtqueue*);
216 void virtio_reset(struct virtio_softc *);
217 void virtio_reinit_start(struct virtio_softc *);
218 void virtio_reinit_end(struct virtio_softc *);
219 
220 int virtio_enqueue_prep(struct virtqueue*, int*);
221 int virtio_enqueue_reserve(struct virtqueue*, int, int);
222 int virtio_enqueue(struct virtqueue*, int, bus_dmamap_t, int);
223 int virtio_enqueue_p(struct virtqueue*, int, bus_dmamap_t, bus_addr_t,
224 		     bus_size_t, int);
225 void virtio_enqueue_commit(struct virtio_softc*, struct virtqueue*, int, int);
226 #define		virtio_notify(sc,vq)	virtio_enqueue_commit(sc, vq, -1, 1)
227 
228 int virtio_enqueue_abort(struct virtqueue*, int);
229 void virtio_enqueue_trim(struct virtqueue*, int, int);
230 
231 int virtio_dequeue(struct virtio_softc*, struct virtqueue*, int *, int *);
232 int virtio_dequeue_commit(struct virtqueue*, int);
233 
234 int virtio_intr(void *arg);
235 int virtio_check_vqs(struct virtio_softc *);
236 void virtio_stop_vq_intr(struct virtio_softc *, struct virtqueue *);
237 int virtio_start_vq_intr(struct virtio_softc *, struct virtqueue *);
238 
239 const char *virtio_device_string(int);
240 #if VIRTIO_DEBUG
241 void virtio_log_features(uint64_t, uint64_t, const struct virtio_feature_name *);
242 void virtio_vq_dump(struct virtqueue *vq);
243 #endif
244 int virtio_nused(struct virtqueue *vq);
245 int virtio_postpone_intr(struct virtqueue *vq, uint16_t nslots);
246 int virtio_postpone_intr_smart(struct virtqueue *vq);
247 int virtio_postpone_intr_far(struct virtqueue *vq);
248 
249 #endif /* _DEV_PV_VIRTIOVAR_H_ */
250