xref: /netbsd-src/sys/dev/altmem/altmem.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /* $NetBSD: altmem.c,v 1.1 2009/03/12 00:15:07 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2009 Jared D. McNeill <jmcneill@invisible.ca>
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. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
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,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __KERNEL_RCSID(0, "$NetBSD: altmem.c,v 1.1 2009/03/12 00:15:07 jmcneill Exp $");
30 #include <sys/param.h>
31 #include <sys/types.h>
32 #include <sys/device.h>
33 #include <sys/conf.h>
34 #include <sys/buf.h>
35 #include <sys/disklabel.h>
36 #include <sys/disk.h>
37 
38 #include <dev/altmem/altmemvar.h>
39 
40 struct altmem_softc {
41 	device_t	sc_dev;
42 
43 	struct disk	sc_dkdev;
44 
45 	void		*sc_cookie;
46 	const struct altmem_memops *sc_memops;
47 
48 	size_t		sc_size;
49 };
50 
51 static dev_type_open(altmemopen);
52 static dev_type_close(altmemclose);
53 static dev_type_read(altmemread);
54 static dev_type_write(altmemwrite);
55 static dev_type_ioctl(altmemioctl);
56 static dev_type_strategy(altmemstrategy);
57 static dev_type_size(altmemsize);
58 
59 static int	altmem_match(device_t, cfdata_t, void *);
60 static void	altmem_attach(device_t, device_t, void *);
61 
62 const struct bdevsw altmem_bdevsw = {
63         altmemopen, altmemclose, altmemstrategy, altmemioctl, nodump,
64 	altmemsize, D_DISK
65 };
66 const struct cdevsw altmem_cdevsw = {
67 	altmemopen, altmemclose, altmemread, altmemwrite, altmemioctl,
68 	nostop, notty, nopoll, nommap, nokqfilter, D_DISK
69 };
70 static struct dkdriver altmemdkdriver = { altmemstrategy, minphys };
71 extern struct cfdriver altmem_cd;
72 
73 CFATTACH_DECL_NEW(altmem, sizeof(struct altmem_softc), altmem_match,
74     altmem_attach, NULL, NULL);
75 
76 static int
77 altmem_match(device_t parent, cfdata_t match, void *opaque)
78 {
79 	return 1;
80 }
81 
82 static void
83 altmem_attach(device_t parent, device_t self, void *opaque)
84 {
85 	struct altmem_softc *sc = device_private(self);
86 	struct altmem_attach_args *aaa = opaque;
87 	char pbuf[9];
88 
89 	sc->sc_dev = self;
90 	sc->sc_cookie = aaa->cookie;
91 	sc->sc_memops = aaa->memops;
92 	sc->sc_size = sc->sc_memops->getsize(sc->sc_cookie);
93 
94 	format_bytes(pbuf, sizeof(pbuf), sc->sc_size);
95 
96 	aprint_naive("\n");
97 	aprint_normal(": %s\n", pbuf);
98 
99 	disk_init(&sc->sc_dkdev, device_xname(self), &altmemdkdriver);
100 	disk_attach(&sc->sc_dkdev);
101 }
102 
103 static int
104 altmemsize(dev_t dev)
105 {
106 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
107 	if (sc == NULL)
108 		return 0;
109 	return sc->sc_size >> DEV_BSHIFT;
110 }
111 
112 static int
113 altmemopen(dev_t dev, int flag, int fmt, struct lwp *l)
114 {
115 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
116 	if (sc == NULL)
117 		return ENXIO;
118 	return 0;
119 }
120 
121 static int
122 altmemclose(dev_t dev, int flag, int fmt, struct lwp *l)
123 {
124 	return 0;
125 }
126 
127 static int
128 altmemread(dev_t dev, struct uio *uio, int flags)
129 {
130 	if (device_lookup_private(&altmem_cd, DISKUNIT(dev)) == NULL)
131 		return ENXIO;
132 	return physio(altmemstrategy, NULL, dev, B_READ, minphys, uio);
133 }
134 
135 static int
136 altmemwrite(dev_t dev, struct uio *uio, int flags)
137 {
138 	if (device_lookup_private(&altmem_cd, DISKUNIT(dev)) == NULL)
139 		return ENXIO;
140 	return physio(altmemstrategy, NULL, dev, B_WRITE, minphys, uio);
141 }
142 
143 static void
144 altmemstrategy(struct buf *bp)
145 {
146 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(bp->b_dev));
147 
148 	if (sc == NULL) {
149 		bp->b_error = ENXIO;
150 		biodone(bp);
151 		return;
152 	}
153 	if (bp->b_bcount == 0) {
154 		biodone(bp);
155 		return;
156 	}
157 
158 	sc->sc_memops->strategy(sc->sc_cookie, bp);
159 	biodone(bp);
160 }
161 
162 static int
163 altmemioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
164 {
165 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
166 	struct dkwedge_info *dkw;
167 
168 	switch (cmd) {
169 	case DIOCGWEDGEINFO:
170 		dkw = (void *)data;
171 		strlcpy(dkw->dkw_devname, device_xname(sc->sc_dev),
172 		    sizeof(dkw->dkw_devname));
173 		strlcpy(dkw->dkw_wname, "altmem", sizeof(dkw->dkw_wname));
174 		dkw->dkw_parent[0] = '\0';
175 		dkw->dkw_offset = 0;
176 		dkw->dkw_size = sc->sc_size >> DEV_BSHIFT;
177 		strcpy(dkw->dkw_ptype, DKW_PTYPE_UNUSED);
178 		break;
179 	default:
180 		return ENOTTY;
181 	}
182 	return 0;
183 }
184