fopsmapper.c revision 1.2.4.2
1 1.2.4.2 martin /* $NetBSD: fopsmapper.c,v 1.2.4.2 2020/04/13 08:05:11 martin Exp $ */ 2 1.2.4.2 martin 3 1.2.4.2 martin /*- 4 1.2.4.2 martin * Copyright (c) 2020 The NetBSD Foundation, Inc. 5 1.2.4.2 martin * All rights reserved. 6 1.2.4.2 martin * 7 1.2.4.2 martin * Redistribution and use in source and binary forms, with or without 8 1.2.4.2 martin * modification, are permitted provided that the following conditions 9 1.2.4.2 martin * are met: 10 1.2.4.2 martin * 1. Redistributions of source code must retain the above copyright 11 1.2.4.2 martin * notice, this list of conditions and the following disclaimer. 12 1.2.4.2 martin * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.4.2 martin * notice, this list of conditions and the following disclaimer in the 14 1.2.4.2 martin * documentation and/or other materials provided with the distribution. 15 1.2.4.2 martin * 16 1.2.4.2 martin * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 1.2.4.2 martin * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 1.2.4.2 martin * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 1.2.4.2 martin * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 1.2.4.2 martin * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 1.2.4.2 martin * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 1.2.4.2 martin * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 1.2.4.2 martin * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 1.2.4.2 martin * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 1.2.4.2 martin * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 1.2.4.2 martin * POSSIBILITY OF SUCH DAMAGE. 27 1.2.4.2 martin */ 28 1.2.4.2 martin 29 1.2.4.2 martin #include <sys/cdefs.h> 30 1.2.4.2 martin __KERNEL_RCSID(0, "$NetBSD: fopsmapper.c,v 1.2.4.2 2020/04/13 08:05:11 martin Exp $"); 31 1.2.4.2 martin 32 1.2.4.2 martin #include <sys/module.h> 33 1.2.4.2 martin #include <sys/param.h> 34 1.2.4.2 martin #include <sys/systm.h> 35 1.2.4.2 martin #include <sys/kernel.h> 36 1.2.4.2 martin 37 1.2.4.2 martin #include <sys/conf.h> 38 1.2.4.2 martin #include <sys/file.h> 39 1.2.4.2 martin #include <sys/filedesc.h> 40 1.2.4.2 martin #include <sys/kmem.h> 41 1.2.4.2 martin #include <sys/mman.h> 42 1.2.4.2 martin #include <sys/mutex.h> 43 1.2.4.2 martin #include <uvm/uvm_extern.h> 44 1.2.4.2 martin 45 1.2.4.2 martin /* 46 1.2.4.2 martin * To use this module you need to: 47 1.2.4.2 martin * 48 1.2.4.2 martin * mknod /dev/fopsmapper c 351 0 49 1.2.4.2 martin * 50 1.2.4.2 martin */ 51 1.2.4.2 martin 52 1.2.4.2 martin dev_type_open(fopsmapper_open); 53 1.2.4.2 martin 54 1.2.4.2 martin const struct cdevsw fopsmapper_cdevsw = { 55 1.2.4.2 martin .d_open = fopsmapper_open, 56 1.2.4.2 martin .d_close = noclose, 57 1.2.4.2 martin .d_read = noread, 58 1.2.4.2 martin .d_write = nowrite, 59 1.2.4.2 martin .d_ioctl = noioctl, 60 1.2.4.2 martin .d_stop = nostop, 61 1.2.4.2 martin .d_tty = notty, 62 1.2.4.2 martin .d_poll = nopoll, 63 1.2.4.2 martin .d_mmap = nommap, 64 1.2.4.2 martin .d_kqfilter = nokqfilter, 65 1.2.4.2 martin .d_discard = nodiscard, 66 1.2.4.2 martin .d_flag = D_OTHER 67 1.2.4.2 martin }; 68 1.2.4.2 martin 69 1.2.4.2 martin static int fopsmapper_mmap(file_t *, off_t *, size_t, 70 1.2.4.2 martin int, int *, int *,struct uvm_object **, int *); 71 1.2.4.2 martin static int fopsmapper_close(file_t *); 72 1.2.4.2 martin 73 1.2.4.2 martin const struct fileops mapper_fileops = { 74 1.2.4.2 martin .fo_read = fbadop_read, 75 1.2.4.2 martin .fo_write = fbadop_write, 76 1.2.4.2 martin .fo_ioctl = fbadop_ioctl, 77 1.2.4.2 martin .fo_fcntl = fnullop_fcntl, 78 1.2.4.2 martin .fo_poll = fnullop_poll, 79 1.2.4.2 martin .fo_stat = fbadop_stat, 80 1.2.4.2 martin .fo_close = fopsmapper_close, 81 1.2.4.2 martin .fo_kqfilter = fnullop_kqfilter, 82 1.2.4.2 martin .fo_restart = fnullop_restart, 83 1.2.4.2 martin .fo_mmap = fopsmapper_mmap, 84 1.2.4.2 martin }; 85 1.2.4.2 martin 86 1.2.4.2 martin typedef struct fopsmapper_softc { 87 1.2.4.2 martin char *buf; 88 1.2.4.2 martin struct uvm_object *uobj; 89 1.2.4.2 martin size_t bufsize; 90 1.2.4.2 martin } fops_t; 91 1.2.4.2 martin 92 1.2.4.2 martin int 93 1.2.4.2 martin fopsmapper_open(dev_t dev, int flag, int mode, struct lwp *l) 94 1.2.4.2 martin { 95 1.2.4.2 martin fops_t *fo; 96 1.2.4.2 martin struct file *fp; 97 1.2.4.2 martin int fd, error; 98 1.2.4.2 martin 99 1.2.4.2 martin if ((error = fd_allocfile(&fp, &fd)) != 0) 100 1.2.4.2 martin return error; 101 1.2.4.2 martin 102 1.2.4.2 martin fo = kmem_zalloc(sizeof(*fo), KM_SLEEP); 103 1.2.4.2 martin 104 1.2.4.2 martin return fd_clone(fp, fd, flag, &mapper_fileops, fo); 105 1.2.4.2 martin } 106 1.2.4.2 martin 107 1.2.4.2 martin int 108 1.2.4.2 martin fopsmapper_mmap(file_t * fp, off_t * offp, size_t size, int prot, 109 1.2.4.2 martin int *flagsp, int *advicep, struct uvm_object **uobjp, 110 1.2.4.2 martin int *maxprotp) 111 1.2.4.2 martin { 112 1.2.4.2 martin fops_t *fo; 113 1.2.4.2 martin int error; 114 1.2.4.2 martin 115 1.2.4.2 martin if (prot & PROT_EXEC) 116 1.2.4.2 martin return EACCES; 117 1.2.4.2 martin 118 1.2.4.2 martin if (size != (size_t)PAGE_SIZE) 119 1.2.4.2 martin return EINVAL; 120 1.2.4.2 martin 121 1.2.4.2 martin if ((fo = fp->f_data) == NULL) 122 1.2.4.2 martin return ENXIO; 123 1.2.4.2 martin 124 1.2.4.2 martin fo->bufsize = size; 125 1.2.4.2 martin fo->uobj = uao_create(size, 0); 126 1.2.4.2 martin 127 1.2.4.2 martin fo->buf = NULL; 128 1.2.4.2 martin /* Map the uvm object into kernel */ 129 1.2.4.2 martin error = uvm_map(kernel_map, (vaddr_t *) &fo->buf, fo->bufsize, 130 1.2.4.2 martin fo->uobj, 0, 0, 131 1.2.4.2 martin UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RW, 132 1.2.4.2 martin UVM_INH_SHARE,UVM_ADV_RANDOM, 0)); 133 1.2.4.2 martin 134 1.2.4.2 martin if (error) { 135 1.2.4.2 martin uao_detach(fo->uobj); 136 1.2.4.2 martin return error; 137 1.2.4.2 martin } 138 1.2.4.2 martin snprintf(fo->buf, 13, "Hey There!"); 139 1.2.4.2 martin 140 1.2.4.2 martin /* Get the reference of uobj */ 141 1.2.4.2 martin uao_reference(fo->uobj); 142 1.2.4.2 martin 143 1.2.4.2 martin *uobjp = fo->uobj; 144 1.2.4.2 martin *maxprotp = prot; 145 1.2.4.2 martin *advicep = UVM_ADV_RANDOM; 146 1.2.4.2 martin 147 1.2.4.2 martin return 0; 148 1.2.4.2 martin } 149 1.2.4.2 martin 150 1.2.4.2 martin int 151 1.2.4.2 martin fopsmapper_close(file_t * fp) 152 1.2.4.2 martin { 153 1.2.4.2 martin fops_t *fo; 154 1.2.4.2 martin 155 1.2.4.2 martin fo = fp->f_data; 156 1.2.4.2 martin KASSERT(fo != NULL); 157 1.2.4.2 martin 158 1.2.4.2 martin if (fo->buf != NULL) 159 1.2.4.2 martin uvm_deallocate(kernel_map, (vaddr_t)fo->buf, fo->bufsize); 160 1.2.4.2 martin 161 1.2.4.2 martin kmem_free(fo, sizeof(*fo)); 162 1.2.4.2 martin 163 1.2.4.2 martin return 0; 164 1.2.4.2 martin } 165 1.2.4.2 martin 166 1.2.4.2 martin MODULE(MODULE_CLASS_MISC, fopsmapper, NULL); 167 1.2.4.2 martin 168 1.2.4.2 martin static int 169 1.2.4.2 martin fopsmapper_modcmd(modcmd_t cmd, void *arg __unused) 170 1.2.4.2 martin { 171 1.2.4.2 martin int cmajor = 351, bmajor = -1; 172 1.2.4.2 martin 173 1.2.4.2 martin switch (cmd) { 174 1.2.4.2 martin case MODULE_CMD_INIT: 175 1.2.4.2 martin if (devsw_attach("fopsmapper", NULL, &bmajor, 176 1.2.4.2 martin &fopsmapper_cdevsw, &cmajor)) 177 1.2.4.2 martin return ENXIO; 178 1.2.4.2 martin return 0; 179 1.2.4.2 martin case MODULE_CMD_FINI: 180 1.2.4.2 martin return EBUSY; 181 1.2.4.2 martin default: 182 1.2.4.2 martin return ENOTTY; 183 1.2.4.2 martin } 184 1.2.4.2 martin } 185
Indexes created Tue Sep 30 07:10:03 GMT 2025