xref: /freebsd/sys/dev/ofw/ofw_disk.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (C) 2002 Benno Rice <benno@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/bio.h>
32 #include <sys/kernel.h>
33 #include <sys/kthread.h>
34 #include <sys/linker.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/mutex.h>
38 #include <sys/proc.h>
39 
40 #include <geom/geom.h>
41 
42 #include <dev/ofw/openfirm.h>
43 
44 #define	OFWD_BLOCKSIZE	512
45 
46 struct ofwd_softc
47 {
48 	struct bio_queue_head ofwd_bio_queue;
49 	struct mtx	ofwd_queue_mtx;
50 	ihandle_t	ofwd_instance;
51 	off_t		ofwd_mediasize;
52 	unsigned	ofwd_sectorsize;
53 	unsigned	ofwd_fwheads;
54 	unsigned	ofwd_fwsectors;
55 	struct proc	*ofwd_procp;
56 	struct g_geom	*ofwd_gp;
57 	struct g_provider *ofwd_pp;
58 } ofwd_softc;
59 
60 static g_init_t g_ofwd_init;
61 static g_start_t g_ofwd_start;
62 static g_access_t g_ofwd_access;
63 
64 struct g_class g_ofwd_class = {
65 	.name = "OFWD",
66 	.version = G_VERSION,
67 	.init = g_ofwd_init,
68 	.start = g_ofwd_start,
69 	.access = g_ofwd_access,
70 };
71 
72 DECLARE_GEOM_CLASS(g_ofwd_class, g_ofwd);
73 
74 static int ofwd_enable = 0;
75 TUNABLE_INT("kern.ofw.disk", &ofwd_enable);
76 
77 static int
78 ofwd_startio(struct ofwd_softc *sc, struct bio *bp)
79 {
80 	u_int r;
81 
82 	r = OF_seek(sc->ofwd_instance, bp->bio_offset);
83 
84 	switch (bp->bio_cmd) {
85 	case BIO_READ:
86 		r = OF_read(sc->ofwd_instance, (void *)bp->bio_data,
87 		   bp->bio_length);
88 		break;
89 	case BIO_WRITE:
90 		r = OF_write(sc->ofwd_instance, (void *)bp->bio_data,
91 		   bp->bio_length);
92 		break;
93 	}
94 	if (r != bp->bio_length)
95 		panic("ofwd: incorrect i/o count");
96 
97 	bp->bio_resid = 0;
98 	return (0);
99 }
100 
101 static void
102 ofwd_kthread(void *arg)
103 {
104 	struct ofwd_softc *sc;
105 	struct bio *bp;
106 	int error;
107 
108 	sc = arg;
109 	curthread->td_base_pri = PRIBIO;
110 
111 	for (;;) {
112 		mtx_lock(&sc->ofwd_queue_mtx);
113 		bp = bioq_takefirst(&sc->ofwd_bio_queue);
114 		if (!bp) {
115 			msleep(sc, &sc->ofwd_queue_mtx, PRIBIO | PDROP,
116 			    "ofwdwait", 0);
117 			continue;
118 		}
119 		mtx_unlock(&sc->ofwd_queue_mtx);
120 		if (bp->bio_cmd == BIO_GETATTR) {
121 			error = EOPNOTSUPP;
122 		} else
123 			error = ofwd_startio(sc, bp);
124 
125 		if (error != -1) {
126 			bp->bio_completed = bp->bio_length;
127 			g_io_deliver(bp, error);
128 		}
129 	}
130 }
131 
132 static void
133 g_ofwd_init(struct g_class *mp __unused)
134 {
135 	char path[128];
136 	char fname[32];
137 	phandle_t ofd;
138 	struct ofwd_softc *sc;
139 	struct g_geom *gp;
140 	struct g_provider *pp;
141 	ihandle_t ifd;
142 	int error;
143 
144 	if (ofwd_enable == 0)
145 		return;
146 
147 	ofd = OF_finddevice("ofwdisk");
148 	if (ofd == -1)
149 		return;
150 
151 	bzero(path, 128);
152 	OF_package_to_path(ofd, path, 128);
153 	OF_getprop(ofd, "file", fname, sizeof(fname));
154 	printf("ofw_disk located at %s, file %s\n", path, fname);
155 	ifd = OF_open(path);
156 	if (ifd == -1) {
157 		printf("ofw_disk: could not create instance\n");
158 		return;
159 	}
160 
161 	sc = (struct ofwd_softc *)malloc(sizeof *sc, M_DEVBUF,
162 	    M_WAITOK | M_ZERO);
163 	bioq_init(&sc->ofwd_bio_queue);
164 	mtx_init(&sc->ofwd_queue_mtx, "ofwd bio queue", NULL, MTX_DEF);
165 	sc->ofwd_instance = ifd;
166 	sc->ofwd_mediasize = (off_t)2 * 33554432;
167 	sc->ofwd_sectorsize = OFWD_BLOCKSIZE;
168 	sc->ofwd_fwsectors = 0;
169 	sc->ofwd_fwheads = 0;
170 	error = kproc_create(ofwd_kthread, sc, &sc->ofwd_procp, 0, 0,
171 	    "ofwd0");
172 	if (error != 0) {
173 		free(sc, M_DEVBUF);
174 		return;
175 	}
176 
177 	gp = g_new_geomf(&g_ofwd_class, "ofwd0");
178 	gp->softc = sc;
179 	pp = g_new_providerf(gp, "ofwd0");
180 	pp->mediasize = sc->ofwd_mediasize;
181 	pp->sectorsize = sc->ofwd_sectorsize;
182 	sc->ofwd_gp = gp;
183 	sc->ofwd_pp = pp;
184 	g_error_provider(pp, 0);
185 }
186 
187 static void
188 g_ofwd_start(struct bio *bp)
189 {
190 	struct ofwd_softc *sc;
191 
192 	sc = bp->bio_to->geom->softc;
193 	mtx_lock(&sc->ofwd_queue_mtx);
194 	bioq_disksort(&sc->ofwd_bio_queue, bp);
195 	mtx_unlock(&sc->ofwd_queue_mtx);
196 	wakeup(sc);
197 }
198 
199 static int
200 g_ofwd_access(struct g_provider *pp, int r, int w, int e)
201 {
202 
203 	if (pp->geom->softc == NULL)
204 		return (ENXIO);
205 	return (0);
206 }
207