1 /* $OpenBSD: diskmap.c,v 1.24 2018/08/20 14:59:02 visa Exp $ */ 2 3 /* 4 * Copyright (c) 2009, 2010 Joel Sing <jsing@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 /* 20 * Disk mapper. 21 */ 22 23 #include <sys/param.h> 24 #include <sys/systm.h> 25 #include <sys/device.h> 26 #include <sys/errno.h> 27 #include <sys/conf.h> 28 #include <sys/dkio.h> 29 #include <sys/disk.h> 30 #include <sys/disklabel.h> 31 #include <sys/fcntl.h> 32 #include <sys/file.h> 33 #include <sys/filedesc.h> 34 #include <sys/lock.h> 35 #include <sys/malloc.h> 36 #include <sys/namei.h> 37 #include <sys/proc.h> 38 #include <sys/vnode.h> 39 #include <sys/pledge.h> 40 #include <sys/namei.h> 41 42 int 43 diskmapopen(dev_t dev, int flag, int fmt, struct proc *p) 44 { 45 return 0; 46 } 47 48 int 49 diskmapclose(dev_t dev, int flag, int fmt, struct proc *p) 50 { 51 return 0; 52 } 53 54 int 55 diskmapioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) 56 { 57 struct dk_diskmap *dm; 58 struct nameidata ndp; 59 struct filedesc *fdp = p->p_fd; 60 struct file *fp0 = NULL, *fp = NULL; 61 struct vnode *vp = NULL; 62 char *devname, flags; 63 int fd, error = EINVAL; 64 65 if (cmd != DIOCMAP) 66 return EINVAL; 67 68 /* 69 * Map a request for a disk to the correct device. We should be 70 * supplied with either a diskname or a disklabel UID. 71 */ 72 73 dm = (struct dk_diskmap *)addr; 74 fd = dm->fd; 75 devname = malloc(PATH_MAX, M_DEVBUF, M_WAITOK); 76 if (copyinstr(dm->device, devname, PATH_MAX, NULL)) 77 goto invalid; 78 if (disk_map(devname, devname, PATH_MAX, dm->flags) == 0) 79 if (copyoutstr(devname, dm->device, PATH_MAX, NULL)) 80 goto invalid; 81 82 /* Attempt to open actual device. */ 83 if ((error = getvnode(p, fd, &fp0)) != 0) 84 goto invalid; 85 86 NDINIT(&ndp, 0, 0, UIO_SYSSPACE, devname, p); 87 ndp.ni_pledge = PLEDGE_RPATH; 88 ndp.ni_unveil = UNVEIL_READ; 89 if ((error = vn_open(&ndp, fp0->f_flag, 0)) != 0) 90 goto invalid; 91 92 vp = ndp.ni_vp; 93 VOP_UNLOCK(vp); 94 95 fdplock(fdp); 96 /* 97 * Stop here if the 'struct file *' has been replaced, 98 * for example by another thread calling dup2(2), while 99 * this thread was sleeping in vn_open(). 100 * 101 * Note that this would not happen for correct usages of 102 * "/dev/diskmap". 103 */ 104 if (fdp->fd_ofiles[fd] != fp0) { 105 error = EAGAIN; 106 goto bad; 107 } 108 109 fp = fnew(p); 110 if (fp == NULL) { 111 error = ENFILE; 112 goto bad; 113 } 114 115 /* Zap old file. */ 116 mtx_enter(&fdp->fd_fplock); 117 KASSERT(fdp->fd_ofiles[fd] == fp0); 118 flags = fdp->fd_ofileflags[fd]; 119 fdp->fd_ofiles[fd] = NULL; 120 fdp->fd_ofileflags[fd] = 0; 121 mtx_leave(&fdp->fd_fplock); 122 123 /* Insert new file. */ 124 fp->f_flag = fp0->f_flag; 125 fp->f_type = DTYPE_VNODE; 126 fp->f_ops = &vnops; 127 fp->f_data = (caddr_t)vp; 128 fdinsert(fdp, fd, flags, fp); 129 fdpunlock(fdp); 130 131 closef(fp0, p); 132 free(devname, M_DEVBUF, PATH_MAX); 133 134 return 0; 135 136 bad: 137 fdpunlock(fdp); 138 139 if (vp) 140 vrele(vp); 141 invalid: 142 if (fp0) 143 FRELE(fp0, p); 144 145 free(devname, M_DEVBUF, PATH_MAX); 146 147 return (error); 148 } 149 150 int 151 diskmapread(dev_t dev, struct uio *uio, int flag) 152 { 153 return ENXIO; 154 } 155 156 int 157 diskmapwrite(dev_t dev, struct uio *uio, int flag) 158 { 159 return ENXIO; 160 } 161