1 /* 2 * Copyright (c) 1993 The Regents of the University of California. 3 * Copyright (c) 1993 Jan-Simon Pendry 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Jan-Simon Pendry. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * From: 38 * Id: procfs_subr.c,v 4.1 1993/12/17 10:47:45 jsp Rel 39 * 40 * $Id: procfs_subr.c,v 1.10 1994/04/25 03:50:01 cgd Exp $ 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/time.h> 46 #include <sys/kernel.h> 47 #include <sys/proc.h> 48 #include <sys/vnode.h> 49 #include <miscfs/procfs/procfs.h> 50 51 static struct pfsnode *pfshead; 52 static int pfsvplock; 53 54 /* 55 * allocate a pfsnode/vnode pair. the vnode is 56 * referenced, but not locked. 57 * 58 * the pid, pfs_type, and mount point uniquely 59 * identify a pfsnode. the mount point is needed 60 * because someone might mount this filesystem 61 * twice. 62 * 63 * all pfsnodes are maintained on a singly-linked 64 * list. new nodes are only allocated when they cannot 65 * be found on this list. entries on the list are 66 * removed when the vfs reclaim entry is called. 67 * 68 * a single lock is kept for the entire list. this is 69 * needed because the getnewvnode() function can block 70 * waiting for a vnode to become free, in which case there 71 * may be more than one process trying to get the same 72 * vnode. this lock is only taken if we are going to 73 * call getnewvnode, since the kernel itself is single-threaded. 74 * 75 * if an entry is found on the list, then call vget() to 76 * take a reference. this is done because there may be 77 * zero references to it and so it needs to removed from 78 * the vnode free list. 79 */ 80 procfs_allocvp(mp, vpp, pid, pfs_type) 81 struct mount *mp; 82 struct vnode **vpp; 83 long pid; 84 pfstype pfs_type; 85 { 86 int error; 87 struct pfsnode *pfs; 88 struct pfsnode **pp; 89 struct vnode *vp; 90 91 loop: 92 for (pfs = pfshead; pfs != 0; pfs = pfs->pfs_next) { 93 if (pfs->pfs_pid == pid && 94 pfs->pfs_type == pfs_type && 95 PFSTOV(pfs)->v_mount == mp) { 96 if (vget(pfs->pfs_vnode, 1)) 97 goto loop; 98 VOP_UNLOCK(pfs->pfs_vnode); 99 *vpp = pfs->pfs_vnode; 100 return (0); 101 } 102 } 103 104 /* 105 * otherwise lock the vp list while we call getnewvnode 106 * since that can block. 107 */ 108 if (pfsvplock & PROCFS_LOCKED) { 109 pfsvplock |= PROCFS_WANT; 110 sleep((caddr_t) &pfsvplock, PINOD); 111 goto loop; 112 } 113 pfsvplock |= PROCFS_LOCKED; 114 115 error = getnewvnode(VT_PROCFS, mp, &procfs_vnodeops, vpp); 116 if (error) 117 goto out; 118 119 /* 4.4: at this point, need to allocate a pfsnode */ 120 121 pfs = VTOPFS(*vpp); 122 pfs->pfs_next = 0; 123 pfs->pfs_pid = (pid_t) pid; 124 pfs->pfs_type = pfs_type; 125 pfs->pfs_vnode = vp = *vpp; 126 pfs->pfs_flags = 0; 127 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type); 128 129 switch (pfs_type) { 130 case Proot: 131 switch ((int)pid) { 132 case 0: /* /proc = dr-xr-xr-x */ 133 pfs->pfs_mode = (VREAD|VEXEC) | 134 (VREAD|VEXEC) >> 3 | 135 (VREAD|VEXEC) >> 6; 136 vp->v_type = VDIR; 137 vp->v_flag = VROOT; 138 break; 139 case 1: /* /proc/curproc = lr--r--r-- */ 140 pfs->pfs_mode = VREAD | 141 VREAD >> 3 | 142 VREAD >> 6; 143 vp->v_type = VLNK; 144 break; 145 default: 146 panic("procfs_allocvp root"); 147 } 148 break; 149 150 case Pproc: 151 pfs->pfs_mode = (VREAD|VEXEC) | 152 (VREAD|VEXEC) >> 3 | 153 (VREAD|VEXEC) >> 6; 154 vp->v_type = VDIR; 155 break; 156 157 case Pmem: 158 pfs->pfs_mode = (VREAD|VWRITE); 159 vp->v_type = VREG; 160 break; 161 162 case Pregs: 163 pfs->pfs_mode = (VREAD|VWRITE); 164 vp->v_type = VREG; 165 break; 166 167 case Pfpregs: 168 pfs->pfs_mode = (VREAD|VWRITE); 169 vp->v_type = VREG; 170 break; 171 172 case Pctl: 173 pfs->pfs_mode = (VREAD|VWRITE); 174 vp->v_type = VREG; 175 break; 176 177 case Pstatus: 178 pfs->pfs_mode = (VREAD) | 179 (VREAD >> 3) | 180 (VREAD >> 6); 181 vp->v_type = VREG; 182 break; 183 184 case Pnote: 185 pfs->pfs_mode = (VREAD|VWRITE); 186 vp->v_type = VREG; 187 break; 188 189 case Pnotepg: 190 pfs->pfs_mode = (VWRITE); 191 vp->v_type = VREG; 192 break; 193 194 default: 195 panic("procfs_allocvp type"); 196 } 197 198 /* add to procfs vnode list */ 199 for (pp = &pfshead; *pp; pp = &(*pp)->pfs_next) 200 continue; 201 *pp = pfs; 202 203 out: 204 pfsvplock &= ~PROCFS_LOCKED; 205 206 if (pfsvplock & PROCFS_WANT) { 207 pfsvplock &= ~PROCFS_WANT; 208 wakeup((caddr_t) &pfsvplock); 209 } 210 211 return (error); 212 } 213 214 procfs_freevp(vp) 215 struct vnode *vp; 216 { 217 struct pfsnode **pfspp; 218 struct pfsnode *pfs = VTOPFS(vp); 219 220 /* 4.4: at this point, need to deallocate the pfsnode */ 221 222 for (pfspp = &pfshead; *pfspp != 0; pfspp = &(*pfspp)->pfs_next) { 223 if (*pfspp == pfs) { 224 *pfspp = pfs->pfs_next; 225 break; 226 } 227 } 228 229 return (0); 230 } 231 232 procfs_rw(vp, uio, ioflag, cred) 233 struct vnode *vp; 234 struct uio *uio; 235 int ioflag; 236 struct ucred *cred; 237 { 238 struct proc *curp = uio->uio_procp; 239 struct pfsnode *pfs = VTOPFS(vp); 240 struct proc *p; 241 242 p = PFIND(pfs->pfs_pid); 243 if (p == 0) 244 return (EINVAL); 245 246 switch (pfs->pfs_type) { 247 case Pnote: 248 case Pnotepg: 249 return (pfs_donote(curp, p, pfs, uio)); 250 251 case Pregs: 252 return (pfs_doregs(curp, p, pfs, uio)); 253 254 case Pfpregs: 255 return (pfs_dofpregs(curp, p, pfs, uio)); 256 257 case Pctl: 258 return (pfs_doctl(curp, p, pfs, uio)); 259 260 case Pstatus: 261 return (pfs_dostatus(curp, p, pfs, uio)); 262 263 case Pmem: 264 return (pfs_domem(curp, p, pfs, uio)); 265 266 default: 267 return (EOPNOTSUPP); 268 } 269 } 270 271 /* 272 * Get a string from userland into (buf). Strip a trailing 273 * nl character (to allow easy access from the shell). 274 * The buffer should be *buflenp + 1 chars long. procfs_getuserstr 275 * will automatically add a nul char at the end. 276 * 277 * Returns 0 on success or the following errors 278 * 279 * EINVAL: file offset is non-zero. 280 * EMSGSIZE: message is longer than kernel buffer 281 * EFAULT: user i/o buffer is not addressable 282 */ 283 procfs_getuserstr(uio, buf, buflenp) 284 struct uio *uio; 285 char *buf; 286 int *buflenp; 287 { 288 int xlen; 289 int error; 290 291 xlen = *buflenp; 292 293 /* must be able to read the whole string in one go */ 294 if (xlen < uio->uio_resid) 295 return (EMSGSIZE); 296 xlen = uio->uio_resid; 297 298 error = uiomove(buf, xlen, uio); 299 if (error) 300 return (error); 301 302 /* cleanup string and remove trailing newline */ 303 buf[xlen] = '\0'; 304 xlen = strlen(buf); 305 if (xlen > 0 && buf[xlen-1] == '\n') 306 buf[--xlen] = '\0'; 307 *buflenp = xlen; 308 309 return (0); 310 } 311 312 procfs_namemap_t * 313 procfs_findname(nm, buf, buflen) 314 procfs_namemap_t *nm; 315 char *buf; 316 int buflen; 317 { 318 for (; nm->nm_name; nm++) 319 if (bcmp(buf, (char *) nm->nm_name, buflen+1) == 0) 320 return (nm); 321 322 return (0); 323 } 324