xref: /openbsd-src/sys/dev/bio.c (revision 3ed8c22999feaa0b7279d15495bb1d93d2fa25e4)
1 /*	$OpenBSD: bio.c,v 1.19 2023/11/15 23:57:45 dlg Exp $	*/
2 
3 /*
4  * Copyright (c) 2002 Niklas Hallqvist.  All rights reserved.
5  * Copyright (c) 2012 Joel Sing <jsing@openbsd.org>.  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 THE AUTHOR ``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 THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 /* A device controller ioctl tunnelling device.  */
29 
30 #include <sys/param.h>
31 #include <sys/device.h>
32 #include <sys/ioctl.h>
33 #include <sys/malloc.h>
34 #include <sys/tree.h>
35 #include <sys/systm.h>
36 
37 #include <dev/biovar.h>
38 
39 struct bio_mapping {
40 	RBT_ENTRY(bio_mapping) bm_link;
41 	uintptr_t bm_cookie;
42 	struct device *bm_dev;
43 	int (*bm_ioctl)(struct device *, u_long, caddr_t);
44 };
45 
46 RBT_HEAD(bio_mappings, bio_mapping);
47 
48 static inline int
bio_cookie_cmp(const struct bio_mapping * a,const struct bio_mapping * b)49 bio_cookie_cmp(const struct bio_mapping *a, const struct bio_mapping *b)
50 {
51 	if (a->bm_cookie < b->bm_cookie)
52 		return (1);
53 	if (a->bm_cookie > b->bm_cookie)
54 		return (-1);
55 	return (0);
56 }
57 
58 RBT_PROTOTYPE(bio_mappings, bio_mapping, bm_link, bio_cookie_cmp);
59 
60 struct bio_mappings bios = RBT_INITIALIZER();
61 
62 void	bioattach(int);
63 int	bioclose(dev_t, int, int, struct proc *);
64 int	bioioctl(dev_t, u_long, caddr_t, int, struct proc *);
65 int	bioopen(dev_t, int, int, struct proc *);
66 
67 int	bio_delegate_ioctl(struct bio_mapping *, u_long, caddr_t);
68 struct	bio_mapping *bio_lookup(char *);
69 struct	bio_mapping *bio_validate(void *);
70 
71 void
bioattach(int nunits)72 bioattach(int nunits)
73 {
74 }
75 
76 int
bioopen(dev_t dev,int flags,int mode,struct proc * p)77 bioopen(dev_t dev, int flags, int mode, struct proc *p)
78 {
79 	return (0);
80 }
81 
82 int
bioclose(dev_t dev,int flags,int mode,struct proc * p)83 bioclose(dev_t dev, int flags, int mode, struct proc *p)
84 {
85 	return (0);
86 }
87 
88 int
bioioctl(dev_t dev,u_long cmd,caddr_t addr,int flag,struct proc * p)89 bioioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
90 {
91 	struct bio_mapping *bm;
92 	struct bio_locate *locate;
93 	struct bio *bio;
94 	char name[16];
95 	int error;
96 
97 	switch (cmd) {
98 	case BIOCLOCATE:
99 		locate = (struct bio_locate *)addr;
100 		error = copyinstr(locate->bl_name, name, sizeof name, NULL);
101 		if (error != 0)
102 			return (error);
103 		bm = bio_lookup(name);
104 		if (bm == NULL)
105 			return (ENOENT);
106 		locate->bl_bio.bio_cookie = (void *)bm->bm_cookie;
107 		break;
108 
109 	default:
110 		bio = (struct bio *)addr;
111 		bm = bio_validate(bio->bio_cookie);
112 		if (bm == NULL)
113 			return (ENOENT);
114 
115 		error = bio_delegate_ioctl(bm, cmd, addr);
116 		break;
117 	}
118 
119 	return (0);
120 }
121 
122 int
bio_register(struct device * dev,int (* ioctl)(struct device *,u_long,caddr_t))123 bio_register(struct device *dev, int (*ioctl)(struct device *, u_long, caddr_t))
124 {
125 	struct bio_mapping *bm;
126 
127 	bm = malloc(sizeof *bm, M_DEVBUF, M_NOWAIT);
128 	if (bm == NULL)
129 		return (ENOMEM);
130 	bm->bm_dev = dev;
131 	bm->bm_ioctl = ioctl;
132 	do {
133 		bm->bm_cookie = arc4random();
134 		/* lets hope we don't have 4 billion bio_registers */
135 	} while (RBT_INSERT(bio_mappings, &bios, bm) != NULL);
136 	return (0);
137 }
138 
139 void
bio_unregister(struct device * dev)140 bio_unregister(struct device *dev)
141 {
142 	struct bio_mapping *bm, *next;
143 
144 	RBT_FOREACH_SAFE(bm, bio_mappings, &bios, next) {
145 		if (dev == bm->bm_dev) {
146 			RBT_REMOVE(bio_mappings, &bios, bm);
147 			free(bm, M_DEVBUF, sizeof(*bm));
148 		}
149 	}
150 }
151 
152 struct bio_mapping *
bio_lookup(char * name)153 bio_lookup(char *name)
154 {
155 	struct bio_mapping *bm;
156 
157 	RBT_FOREACH(bm, bio_mappings, &bios) {
158 		if (strcmp(name, bm->bm_dev->dv_xname) == 0)
159 			return (bm);
160 	}
161 
162 	return (NULL);
163 }
164 
165 struct bio_mapping *
bio_validate(void * cookie)166 bio_validate(void *cookie)
167 {
168 	struct bio_mapping key = { .bm_cookie = (uintptr_t)cookie };
169 
170 	return (RBT_FIND(bio_mappings, &bios, &key));
171 }
172 
173 int
bio_delegate_ioctl(struct bio_mapping * bm,u_long cmd,caddr_t addr)174 bio_delegate_ioctl(struct bio_mapping *bm, u_long cmd, caddr_t addr)
175 {
176 	return (bm->bm_ioctl(bm->bm_dev, cmd, addr));
177 }
178 
179 void
bio_info(struct bio_status * bs,int print,const char * fmt,...)180 bio_info(struct bio_status *bs, int print, const char *fmt, ...)
181 {
182 	va_list	ap;
183 
184 	va_start(ap, fmt);
185 	bio_status(bs, print, BIO_MSG_INFO, fmt, &ap);
186 	va_end(ap);
187 }
188 
189 void
bio_warn(struct bio_status * bs,int print,const char * fmt,...)190 bio_warn(struct bio_status *bs, int print, const char *fmt, ...)
191 {
192 	va_list	ap;
193 
194 	va_start(ap, fmt);
195 	bio_status(bs, print, BIO_MSG_WARN, fmt, &ap);
196 	va_end(ap);
197 }
198 
199 void
bio_error(struct bio_status * bs,int print,const char * fmt,...)200 bio_error(struct bio_status *bs, int print, const char *fmt, ...)
201 {
202 	va_list	ap;
203 
204 	va_start(ap, fmt);
205 	bio_status(bs, print, BIO_MSG_ERROR, fmt, &ap);
206 	va_end(ap);
207 }
208 
209 void
bio_status_init(struct bio_status * bs,struct device * dv)210 bio_status_init(struct bio_status *bs, struct device *dv)
211 {
212 	bzero(bs, sizeof(struct bio_status));
213 
214 	bs->bs_status = BIO_STATUS_UNKNOWN;
215 
216 	strlcpy(bs->bs_controller, dv->dv_xname, sizeof(bs->bs_controller));
217 }
218 
219 void
bio_status(struct bio_status * bs,int print,int msg_type,const char * fmt,va_list * ap)220 bio_status(struct bio_status *bs, int print, int msg_type, const char *fmt,
221     va_list *ap)
222 {
223 	int idx;
224 
225 	if (bs->bs_msg_count >= BIO_MSG_COUNT) {
226 		printf("%s: insufficient message buffers\n", bs->bs_controller);
227 		return;
228 	}
229 
230 	idx = bs->bs_msg_count++;
231 
232 	bs->bs_msgs[idx].bm_type = msg_type;
233 	vsnprintf(bs->bs_msgs[idx].bm_msg, BIO_MSG_LEN, fmt, *ap);
234 
235 	if (print)
236 		printf("%s: %s\n", bs->bs_controller, bs->bs_msgs[idx].bm_msg);
237 }
238 
239 RBT_GENERATE(bio_mappings, bio_mapping, bm_link, bio_cookie_cmp);
240