xref: /netbsd-src/sys/dev/altmem/altmem.c (revision 82b8caba92d0ece070500659c43d13d9ecc6921e)
1 /* $NetBSD: altmem.c,v 1.6 2017/10/28 04:53:55 riastradh 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 1.6 2017/10/28 04:53:55 riastradh 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 #include "ioconf.h"
41 
42 struct altmem_softc {
43 	device_t	sc_dev;
44 
45 	struct disk	sc_dkdev;
46 
47 	void		*sc_cookie;
48 	const struct altmem_memops *sc_memops;
49 
50 	size_t		sc_size;
51 };
52 
53 static dev_type_open(altmemopen);
54 static dev_type_close(altmemclose);
55 static dev_type_read(altmemread);
56 static dev_type_write(altmemwrite);
57 static dev_type_ioctl(altmemioctl);
58 static dev_type_strategy(altmemstrategy);
59 static dev_type_size(altmemsize);
60 
61 static int	altmem_match(device_t, cfdata_t, void *);
62 static void	altmem_attach(device_t, device_t, void *);
63 
64 const struct bdevsw altmem_bdevsw = {
65         .d_open = altmemopen,
66 	.d_close = altmemclose,
67 	.d_strategy = altmemstrategy,
68 	.d_ioctl = altmemioctl,
69 	.d_dump = nodump,
70 	.d_psize = altmemsize,
71 	.d_discard = nodiscard,
72 	.d_flag = D_DISK
73 };
74 const struct cdevsw altmem_cdevsw = {
75 	.d_open = altmemopen,
76 	.d_close = altmemclose,
77 	.d_read = altmemread,
78 	.d_write = altmemwrite,
79 	.d_ioctl = altmemioctl,
80 	.d_stop = nostop,
81 	.d_tty = notty,
82 	.d_poll = nopoll,
83 	.d_mmap = nommap,
84 	.d_kqfilter = nokqfilter,
85 	.d_discard = nodiscard,
86 	.d_flag = D_DISK
87 };
88 static struct dkdriver altmemdkdriver = {
89 	.d_strategy = altmemstrategy,
90 	.d_minphys = minphys
91 };
92 
93 CFATTACH_DECL_NEW(altmem, sizeof(struct altmem_softc), altmem_match,
94     altmem_attach, NULL, NULL);
95 
96 static int
altmem_match(device_t parent,cfdata_t match,void * opaque)97 altmem_match(device_t parent, cfdata_t match, void *opaque)
98 {
99 	return 1;
100 }
101 
102 static void
altmem_attach(device_t parent,device_t self,void * opaque)103 altmem_attach(device_t parent, device_t self, void *opaque)
104 {
105 	struct altmem_softc *sc = device_private(self);
106 	struct altmem_attach_args *aaa = opaque;
107 	char pbuf[9];
108 
109 	sc->sc_dev = self;
110 	sc->sc_cookie = aaa->cookie;
111 	sc->sc_memops = aaa->memops;
112 	sc->sc_size = sc->sc_memops->getsize(sc->sc_cookie);
113 
114 	format_bytes(pbuf, sizeof(pbuf), sc->sc_size);
115 
116 	aprint_naive("\n");
117 	aprint_normal(": %s\n", pbuf);
118 
119 	disk_init(&sc->sc_dkdev, device_xname(self), &altmemdkdriver);
120 	disk_attach(&sc->sc_dkdev);
121 }
122 
123 static int
altmemsize(dev_t dev)124 altmemsize(dev_t dev)
125 {
126 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
127 	if (sc == NULL)
128 		return 0;
129 	return sc->sc_size >> DEV_BSHIFT;
130 }
131 
132 static int
altmemopen(dev_t dev,int flag,int fmt,struct lwp * l)133 altmemopen(dev_t dev, int flag, int fmt, struct lwp *l)
134 {
135 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
136 	if (sc == NULL)
137 		return ENXIO;
138 	return 0;
139 }
140 
141 static int
altmemclose(dev_t dev,int flag,int fmt,struct lwp * l)142 altmemclose(dev_t dev, int flag, int fmt, struct lwp *l)
143 {
144 	return 0;
145 }
146 
147 static int
altmemread(dev_t dev,struct uio * uio,int flags)148 altmemread(dev_t dev, struct uio *uio, int flags)
149 {
150 	if (device_lookup_private(&altmem_cd, DISKUNIT(dev)) == NULL)
151 		return ENXIO;
152 	return physio(altmemstrategy, NULL, dev, B_READ, minphys, uio);
153 }
154 
155 static int
altmemwrite(dev_t dev,struct uio * uio,int flags)156 altmemwrite(dev_t dev, struct uio *uio, int flags)
157 {
158 	if (device_lookup_private(&altmem_cd, DISKUNIT(dev)) == NULL)
159 		return ENXIO;
160 	return physio(altmemstrategy, NULL, dev, B_WRITE, minphys, uio);
161 }
162 
163 static void
altmemstrategy(struct buf * bp)164 altmemstrategy(struct buf *bp)
165 {
166 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(bp->b_dev));
167 
168 	if (sc == NULL) {
169 		bp->b_error = ENXIO;
170 		biodone(bp);
171 		return;
172 	}
173 	if (bp->b_bcount == 0) {
174 		biodone(bp);
175 		return;
176 	}
177 
178 	sc->sc_memops->strategy(sc->sc_cookie, bp);
179 	biodone(bp);
180 }
181 
182 static int
altmemioctl(dev_t dev,u_long cmd,void * data,int flag,struct lwp * l)183 altmemioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
184 {
185 	struct altmem_softc *sc = device_lookup_private(&altmem_cd, DISKUNIT(dev));
186 	struct dkwedge_info *dkw;
187 
188 	switch (cmd) {
189 	case DIOCGWEDGEINFO:
190 		dkw = (void *)data;
191 		strlcpy(dkw->dkw_devname, device_xname(sc->sc_dev),
192 		    sizeof(dkw->dkw_devname));
193 		strlcpy(dkw->dkw_wname, "altmem", sizeof(dkw->dkw_wname));
194 		dkw->dkw_parent[0] = '\0';
195 		dkw->dkw_offset = 0;
196 		dkw->dkw_size = sc->sc_size >> DEV_BSHIFT;
197 		strcpy(dkw->dkw_ptype, DKW_PTYPE_UNUSED);
198 		break;
199 	default:
200 		return ENOTTY;
201 	}
202 	return 0;
203 }
204