xref: /freebsd/sys/dev/ofw/ofw_disk.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
1 /*-
2  * Copyright (C) 2002 Benno Rice <benno@FreeBSD.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, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
18  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
22  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
23  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/bio.h>
34 #include <sys/kernel.h>
35 #include <sys/kthread.h>
36 #include <sys/linker.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/proc.h>
41 
42 #include <geom/geom.h>
43 
44 #include <dev/ofw/openfirm.h>
45 
46 #define	OFWD_BLOCKSIZE	512
47 
48 struct ofwd_softc
49 {
50         struct bio_queue_head ofwd_bio_queue;
51         struct mtx	ofwd_queue_mtx;
52 	ihandle_t	ofwd_instance;
53 	off_t		ofwd_mediasize;
54         unsigned	ofwd_sectorsize;
55         unsigned	ofwd_fwheads;
56         unsigned	ofwd_fwsectors;
57         struct proc	*ofwd_procp;
58         struct g_geom	*ofwd_gp;
59         struct g_provider *ofwd_pp;
60 } ofwd_softc;
61 
62 static g_init_t g_ofwd_init;
63 static g_start_t g_ofwd_start;
64 static g_access_t g_ofwd_access;
65 
66 struct g_class g_ofwd_class = {
67 	.name = "OFWD",
68 	.version = G_VERSION,
69 	.init = g_ofwd_init,
70 	.start = g_ofwd_start,
71 	.access = g_ofwd_access,
72 };
73 
74 DECLARE_GEOM_CLASS(g_ofwd_class, g_ofwd);
75 
76 static int ofwd_enable = 0;
77 TUNABLE_INT("kern.ofw.disk", &ofwd_enable);
78 
79 static int
80 ofwd_startio(struct ofwd_softc *sc, struct bio *bp)
81 {
82 	u_int r;
83 
84 	r = OF_seek(sc->ofwd_instance, bp->bio_offset);
85         switch (bp->bio_cmd) {
86         case BIO_READ:
87 		r = OF_read(sc->ofwd_instance, (void *)bp->bio_data,
88 		        bp->bio_length);
89                 break;
90         case BIO_WRITE:
91 		r = OF_write(sc->ofwd_instance, (void *)bp->bio_data,
92 		        bp->bio_length);
93                 break;
94         }
95 	if (r != bp->bio_length)
96 		panic("ofwd: incorrect i/o count");
97 
98         bp->bio_resid = 0;
99         return (0);
100 }
101 
102 static void
103 ofwd_kthread(void *arg)
104 {
105 	struct ofwd_softc *sc;
106 	struct bio *bp;
107 	int error;
108 
109         sc = arg;
110         curthread->td_base_pri = PRIBIO;
111 
112         for (;;) {
113 		mtx_lock(&sc->ofwd_queue_mtx);
114 		bp = bioq_takefirst(&sc->ofwd_bio_queue);
115 		if (!bp) {
116 			msleep(sc, &sc->ofwd_queue_mtx, PRIBIO | PDROP,
117 			    "ofwdwait", 0);
118                         continue;
119 		}
120                 mtx_unlock(&sc->ofwd_queue_mtx);
121                 if (bp->bio_cmd == BIO_GETATTR) {
122 			error = EOPNOTSUPP;
123                 } else
124 			error = ofwd_startio(sc, bp);
125 
126 		if (error != -1) {
127                         bp->bio_completed = bp->bio_length;
128                         g_io_deliver(bp, error);
129                 }
130 	}
131 }
132 
133 static void
134 g_ofwd_init(struct g_class *mp __unused)
135 {
136 	struct ofwd_softc *sc;
137         struct g_geom *gp;
138         struct g_provider *pp;
139 	char	path[128];
140 	char	fname[32];
141 	phandle_t ofd;
142 	ihandle_t ifd;
143 	int	error;
144 
145 	if (ofwd_enable == 0)
146 		return;
147 
148 	ofd = OF_finddevice("ofwdisk");
149 	if (ofd == -1)
150 		return;
151 
152 	bzero(path, 128);
153 	OF_package_to_path(ofd, path, 128);
154 	OF_getprop(ofd, "file", fname, sizeof(fname));
155 	printf("ofw_disk located at %s, file %s\n", path, fname);
156 	ifd = OF_open(path);
157 	if (ifd == -1) {
158 		printf("ofw_disk: could not create instance\n");
159 		return;
160 	}
161 
162 	sc = (struct ofwd_softc *)malloc(sizeof *sc, M_DEVBUF,
163 	         M_WAITOK|M_ZERO);
164 	bioq_init(&sc->ofwd_bio_queue);
165         mtx_init(&sc->ofwd_queue_mtx, "ofwd bio queue", NULL, MTX_DEF);
166 	sc->ofwd_instance = ifd;
167 	sc->ofwd_mediasize = (off_t)2*33554432 * OFWD_BLOCKSIZE;
168 	sc->ofwd_sectorsize = OFWD_BLOCKSIZE;
169 	sc->ofwd_fwsectors = 0;
170 	sc->ofwd_fwheads = 0;
171 	error = kthread_create(ofwd_kthread, sc, &sc->ofwd_procp, 0, 0,
172 		     "ofwd0");
173         if (error != 0) {
174 		free(sc, M_DEVBUF);
175                 return;
176 	}
177 
178 	gp = g_new_geomf(&g_ofwd_class, "ofwd0");
179 	gp->softc = sc;
180 	pp = g_new_providerf(gp, "ofwd0");
181 	pp->mediasize = sc->ofwd_mediasize;
182 	pp->sectorsize = sc->ofwd_sectorsize;
183 	sc->ofwd_gp = gp;
184 	sc->ofwd_pp = pp;
185 	g_error_provider(pp, 0);
186 }
187 
188 static void
189 g_ofwd_start(struct bio *bp)
190 {
191         struct ofwd_softc *sc;
192 
193         sc = bp->bio_to->geom->softc;
194         mtx_lock(&sc->ofwd_queue_mtx);
195         bioq_disksort(&sc->ofwd_bio_queue, bp);
196         mtx_unlock(&sc->ofwd_queue_mtx);
197         wakeup(sc);
198 }
199 
200 static int
201 g_ofwd_access(struct g_provider *pp, int r, int w, int e)
202 {
203 
204 	if (pp->geom->softc == NULL)
205 		return (ENXIO);
206         return (0);
207 }
208