1 /* $OpenBSD: bio.c,v 1.11 2007/12/23 17:09:49 deraadt Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Niklas Hallqvist. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 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, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 /* A device controller ioctl tunnelling device. */ 28 29 #include <sys/param.h> 30 #include <sys/device.h> 31 #include <sys/ioctl.h> 32 #include <sys/malloc.h> 33 #include <sys/queue.h> 34 #include <sys/systm.h> 35 36 #include <dev/biovar.h> 37 38 struct bio_mapping { 39 LIST_ENTRY(bio_mapping) bm_link; 40 struct device *bm_dev; 41 int (*bm_ioctl)(struct device *, u_long, caddr_t); 42 }; 43 44 LIST_HEAD(, bio_mapping) bios = LIST_HEAD_INITIALIZER(bios); 45 46 void bioattach(int); 47 int bioclose(dev_t, int, int, struct proc *); 48 int bioioctl(dev_t, u_long, caddr_t, int, struct proc *); 49 int bioopen(dev_t, int, int, struct proc *); 50 51 int bio_delegate_ioctl(struct bio_mapping *, u_long, caddr_t); 52 struct bio_mapping *bio_lookup(char *); 53 int bio_validate(void *); 54 55 void 56 bioattach(int nunits) 57 { 58 } 59 60 int 61 bioopen(dev_t dev, int flags, int mode, struct proc *p) 62 { 63 return (0); 64 } 65 66 int 67 bioclose(dev_t dev, int flags, int mode, struct proc *p) 68 { 69 return (0); 70 } 71 72 int 73 bioioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) 74 { 75 struct bio_locate *locate; 76 struct bio_common *common; 77 char name[16]; 78 int error; 79 80 switch (cmd) { 81 case BIOCLOCATE: 82 locate = (struct bio_locate *)addr; 83 error = copyinstr(locate->bl_name, name, sizeof name, NULL); 84 if (error != 0) 85 return (error); 86 locate->bl_cookie = bio_lookup(name); 87 if (locate->bl_cookie == NULL) 88 return (ENOENT); 89 break; 90 91 default: 92 common = (struct bio_common *)addr; 93 if (!bio_validate(common->bc_cookie)) 94 return (ENOENT); 95 return (bio_delegate_ioctl( 96 (struct bio_mapping *)common->bc_cookie, cmd, addr)); 97 } 98 return (0); 99 } 100 101 int 102 bio_register(struct device *dev, int (*ioctl)(struct device *, u_long, caddr_t)) 103 { 104 struct bio_mapping *bm; 105 106 bm = malloc(sizeof *bm, M_DEVBUF, M_NOWAIT); 107 if (bm == NULL) 108 return (ENOMEM); 109 bm->bm_dev = dev; 110 bm->bm_ioctl = ioctl; 111 LIST_INSERT_HEAD(&bios, bm, bm_link); 112 return (0); 113 } 114 115 void 116 bio_unregister(struct device *dev) 117 { 118 struct bio_mapping *bm, *next; 119 120 for (bm = LIST_FIRST(&bios); bm != NULL; bm = next) { 121 next = LIST_NEXT(bm, bm_link); 122 123 if (dev == bm->bm_dev) { 124 LIST_REMOVE(bm, bm_link); 125 free(bm, M_DEVBUF); 126 } 127 } 128 } 129 130 struct bio_mapping * 131 bio_lookup(char *name) 132 { 133 struct bio_mapping *bm; 134 135 LIST_FOREACH(bm, &bios, bm_link) 136 if (strcmp(name, bm->bm_dev->dv_xname) == 0) 137 return (bm); 138 return (NULL); 139 } 140 141 int 142 bio_validate(void *cookie) 143 { 144 struct bio_mapping *bm; 145 146 LIST_FOREACH(bm, &bios, bm_link) 147 if (bm == cookie) 148 return (1); 149 return (0); 150 } 151 152 int 153 bio_delegate_ioctl(struct bio_mapping *bm, u_long cmd, caddr_t addr) 154 { 155 return (bm->bm_ioctl(bm->bm_dev, cmd, addr)); 156 } 157