xref: /freebsd/sys/dev/virtio/scsi/virtio_scsivar.h (revision 7d99ab9fd0cc2c1ce2ecef0ed6d0672c2a50b0cb)
1 /*-
2  * Copyright (c) 2012, Bryan Venteicher <bryanv@daemoninthecloset.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _VIRTIO_SCSIVAR_H
30 #define _VIRTIO_SCSIVAR_H
31 
32 struct vtscsi_softc;
33 struct vtscsi_request;
34 
35 typedef void vtscsi_request_cb_t(struct vtscsi_softc *,
36     struct vtscsi_request *);
37 
38 struct vtscsi_statistics {
39 	unsigned long		scsi_cmd_timeouts;
40 	unsigned long		dequeue_no_requests;
41 };
42 
43 struct vtscsi_softc {
44 	device_t		 vtscsi_dev;
45 	struct mtx		 vtscsi_mtx;
46 	uint64_t		 vtscsi_features;
47 
48 	uint16_t		 vtscsi_flags;
49 #define VTSCSI_FLAG_INDIRECT		0x0001
50 #define VTSCSI_FLAG_BIDIRECTIONAL	0x0002
51 #define VTSCSI_FLAG_HOTPLUG		0x0004
52 #define VTSCSI_FLAG_RESET		0x0008
53 #define VTSCSI_FLAG_DETACH		0x0010
54 
55 	uint16_t		 vtscsi_frozen;
56 #define VTSCSI_FROZEN_NO_REQUESTS	0x01
57 #define VTSCSI_FROZEN_REQUEST_VQ_FULL	0x02
58 
59 	struct sglist		*vtscsi_sglist;
60 
61 	struct virtqueue	*vtscsi_control_vq;
62 	struct virtqueue	*vtscsi_event_vq;
63 	struct virtqueue	*vtscsi_request_vq;
64 
65 	struct taskqueue	*vtscsi_tq;
66 	struct task		 vtscsi_control_intr_task;
67 	struct task		 vtscsi_event_intr_task;
68 	struct task		 vtscsi_request_intr_task;
69 
70 	struct cam_sim		*vtscsi_sim;
71 	struct cam_path		*vtscsi_path;
72 
73 	int			 vtscsi_debug;
74 	int			 vtscsi_nrequests;
75 	int			 vtscsi_max_nsegs;
76 	int			 vtscsi_event_buf_size;
77 
78 	TAILQ_HEAD(,vtscsi_request)
79 				 vtscsi_req_free;
80 
81 	uint16_t		 vtscsi_max_channel;
82 	uint16_t		 vtscsi_max_target;
83 	uint32_t		 vtscsi_max_lun;
84 
85 #define VTSCSI_NUM_EVENT_BUFS	4
86 	struct virtio_scsi_event
87 				 vtscsi_event_bufs[VTSCSI_NUM_EVENT_BUFS];
88 
89 	struct vtscsi_statistics vtscsi_stats;
90 };
91 
92 enum vtscsi_request_state {
93 	VTSCSI_REQ_STATE_FREE,
94 	VTSCSI_REQ_STATE_INUSE,
95 	VTSCSI_REQ_STATE_ABORTED,
96 	VTSCSI_REQ_STATE_TIMEDOUT
97 };
98 
99 struct vtscsi_request {
100 	struct vtscsi_softc			*vsr_softc;
101 	union ccb				*vsr_ccb;
102 	vtscsi_request_cb_t			*vsr_complete;
103 
104 	void					*vsr_ptr0;
105 /* Request when aborting a timedout command. */
106 #define vsr_timedout_req	vsr_ptr0
107 
108 	enum vtscsi_request_state		 vsr_state;
109 
110 	uint16_t				 vsr_flags;
111 #define VTSCSI_REQ_FLAG_POLLED		0x01
112 #define VTSCSI_REQ_FLAG_COMPLETE	0x02
113 #define VTSCSI_REQ_FLAG_TIMEOUT_SET	0x04
114 
115 	union {
116 		struct virtio_scsi_cmd_req	 cmd;
117 		struct virtio_scsi_ctrl_tmf_req	 tmf;
118 		struct virtio_scsi_ctrl_an_req	 an;
119 	} vsr_ureq;
120 #define vsr_cmd_req 	vsr_ureq.cmd
121 #define vsr_tmf_req 	vsr_ureq.tmf
122 #define vsr_an_req	vsr_ureq.an
123 
124 	/* Make request and response non-contiguous. */
125 	uint32_t				 vsr_pad;
126 
127 	union {
128 		struct virtio_scsi_cmd_resp	 cmd;
129 		struct virtio_scsi_ctrl_tmf_resp tmf;
130 		struct virtio_scsi_ctrl_an_resp	 an;
131 	} vsr_uresp;
132 #define vsr_cmd_resp	vsr_uresp.cmd
133 #define vsr_tmf_resp	vsr_uresp.tmf
134 #define vsr_an_resp	vsr_uresp.an
135 
136 	struct callout				 vsr_callout;
137 
138 	TAILQ_ENTRY(vtscsi_request)		 vsr_link;
139 };
140 
141 /* Private field in the CCB header that points to our request. */
142 #define ccbh_vtscsi_req	spriv_ptr0
143 
144 /* Features desired/implemented by this driver. */
145 #define VTSCSI_FEATURES \
146     (VIRTIO_SCSI_F_HOTPLUG		| \
147      VIRTIO_RING_F_INDIRECT_DESC)
148 
149 #define VTSCSI_MTX(_sc)			&(_sc)->vtscsi_mtx
150 #define VTSCSI_LOCK_INIT(_sc, _name) 	mtx_init(VTSCSI_MTX(_sc), _name, \
151 					    "VTSCSI Lock", MTX_DEF)
152 #define VTSCSI_LOCK(_sc)		mtx_lock(VTSCSI_MTX(_sc))
153 #define VTSCSI_UNLOCK(_sc)		mtx_unlock(VTSCSI_MTX(_sc))
154 #define VTSCSI_LOCK_OWNED(_sc)		mtx_assert(VTSCSI_MTX(_sc), MA_OWNED)
155 #define VTSCSI_LOCK_NOTOWNED(_sc) 	mtx_assert(VTSCSI_MTX(_sc), MA_NOTOWNED)
156 #define VTSCSI_LOCK_DESTROY(_sc)	mtx_destroy(VTSCSI_MTX(_sc))
157 
158 /*
159  * Reasons for either freezing or thawing the SIMQ.
160  *
161  * VirtIO SCSI is a bit unique in the sense that SCSI and TMF
162  * commands go over different queues. Both queues are fed by
163  * the same SIMQ, but we only freeze the SIMQ when the request
164  * (SCSI) virtqueue is full, not caring if the control (TMF)
165  * virtqueue unlikely gets full. However, both queues share the
166  * same pool of requests, so the completion of a TMF command
167  * could cause the SIMQ to be unfrozen.
168  */
169 #define VTSCSI_REQUEST		0x01
170 #define VTSCSI_REQUEST_VQ	0x02
171 
172 /* Debug trace levels. */
173 #define VTSCSI_INFO	0x01
174 #define VTSCSI_ERROR	0x02
175 #define VTSCSI_TRACE	0x04
176 
177 #define vtscsi_dprintf(_sc, _level, _msg, _args ...) do { 		\
178 	if ((_sc)->vtscsi_debug & (_level))				\
179 		device_printf((_sc)->vtscsi_dev, "%s: "_msg,		\
180 		    __FUNCTION__, ##_args);				\
181 } while (0)
182 
183 #define vtscsi_dprintf_req(_req, _level, _msg, _args ...) do {		\
184 	struct vtscsi_softc *__sc = (_req)->vsr_softc;			\
185 	if ((__sc)->vtscsi_debug & (_level))				\
186 		vtscsi_printf_req(_req, __FUNCTION__, _msg, ##_args);	\
187 } while (0)
188 
189 /*
190  * Set the status field in a CCB, optionally clearing non CCB_STATUS_* flags.
191  */
192 #define vtscsi_set_ccb_status(_ccbh, _status, _mask) do {		\
193 	KASSERT(((_mask) & CAM_STATUS_MASK) == 0,			\
194 	    ("%s:%d bad mask: 0x%x", __FUNCTION__, __LINE__, (_mask)));	\
195 	(_ccbh)->status &= ~(CAM_STATUS_MASK | (_mask));		\
196 	(_ccbh)->status |= (_status);					\
197 } while (0)
198 
199 /*
200  * One segment each for the request and the response.
201  */
202 #define VTSCSI_MIN_SEGMENTS	2
203 
204 /*
205  * Allocate additional requests for internal use such
206  * as TM commands (e.g. aborting timedout commands).
207  */
208 #define VTSCSI_RESERVED_REQUESTS	10
209 
210 /*
211  * Specification doesn't say, use traditional SCSI default.
212  */
213 #define VTSCSI_INITIATOR_ID	7
214 
215 /*
216  * How to wait (or not) for request completion.
217  */
218 #define VTSCSI_EXECUTE_ASYNC	0
219 #define VTSCSI_EXECUTE_POLL	1
220 
221 #endif /* _VIRTIO_SCSIVAR_H */
222