procfs_subr.c revision 1.47
1 /* $NetBSD: procfs_subr.c,v 1.47 2003/03/04 18:55:02 tron Exp $ */ 2 3 /* 4 * Copyright (c) 1994 Christopher G. Demetriou. All rights reserved. 5 * Copyright (c) 1993 Jan-Simon Pendry 6 * Copyright (c) 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Jan-Simon Pendry. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: procfs_subr.c,v 1.47 2003/03/04 18:55:02 tron Exp $"); 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/proc.h> 51 #include <sys/vnode.h> 52 #include <sys/malloc.h> 53 #include <sys/stat.h> 54 #include <sys/file.h> 55 #include <sys/filedesc.h> 56 57 #include <miscfs/procfs/procfs.h> 58 59 void procfs_hashins __P((struct pfsnode *)); 60 void procfs_hashrem __P((struct pfsnode *)); 61 struct vnode *procfs_hashget __P((pid_t, pfstype, int, struct mount *)); 62 63 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl; 64 u_long pfs_ihash; /* size of hash table - 1 */ 65 #define PFSPIDHASH(pid) ((pid) & pfs_ihash) 66 67 struct lock pfs_hashlock; 68 struct simplelock pfs_hash_slock; 69 70 #define ISSET(t, f) ((t) & (f)) 71 72 /* 73 * allocate a pfsnode/vnode pair. the vnode is 74 * referenced, and locked. 75 * 76 * the pid, pfs_type, and mount point uniquely 77 * identify a pfsnode. the mount point is needed 78 * because someone might mount this filesystem 79 * twice. 80 * 81 * all pfsnodes are maintained on a singly-linked 82 * list. new nodes are only allocated when they cannot 83 * be found on this list. entries on the list are 84 * removed when the vfs reclaim entry is called. 85 * 86 * a single lock is kept for the entire list. this is 87 * needed because the getnewvnode() function can block 88 * waiting for a vnode to become free, in which case there 89 * may be more than one process trying to get the same 90 * vnode. this lock is only taken if we are going to 91 * call getnewvnode, since the kernel itself is single-threaded. 92 * 93 * if an entry is found on the list, then call vget() to 94 * take a reference. this is done because there may be 95 * zero references to it and so it needs to removed from 96 * the vnode free list. 97 */ 98 int 99 procfs_allocvp(mp, vpp, pid, pfs_type, fd) 100 struct mount *mp; 101 struct vnode **vpp; 102 pid_t pid; 103 pfstype pfs_type; 104 int fd; 105 { 106 struct pfsnode *pfs; 107 struct vnode *vp; 108 int error; 109 110 do { 111 if ((*vpp = procfs_hashget(pid, pfs_type, fd, mp)) != NULL) 112 return (0); 113 } while (lockmgr(&pfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0)); 114 115 if ((error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, &vp)) != 0) { 116 *vpp = NULL; 117 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 118 return (error); 119 } 120 121 MALLOC(pfs, void *, sizeof(struct pfsnode), M_TEMP, M_WAITOK); 122 vp->v_data = pfs; 123 124 pfs->pfs_pid = pid; 125 pfs->pfs_type = pfs_type; 126 pfs->pfs_vnode = vp; 127 pfs->pfs_flags = 0; 128 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type, fd); 129 pfs->pfs_fd = fd; 130 131 switch (pfs_type) { 132 case Proot: /* /proc = dr-xr-xr-x */ 133 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 134 vp->v_type = VDIR; 135 vp->v_flag = VROOT; 136 break; 137 138 case Pcurproc: /* /proc/curproc = lr-xr-xr-x */ 139 case Pself: /* /proc/self = lr-xr-xr-x */ 140 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 141 vp->v_type = VLNK; 142 break; 143 144 case Pproc: /* /proc/N = dr-xr-xr-x */ 145 case Pfd: 146 if (fd == -1) { /* /proc/N/fd = dr-xr-xr-x */ 147 pfs->pfs_mode = 148 S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 149 vp->v_type = VDIR; 150 } else { /* /proc/N/fd/M = [ps-]rw------- */ 151 struct file *fp; 152 struct vnode *vxp; 153 154 /* XXX can procfs_getfp() ever fail here? */ 155 if ((error = procfs_getfp(pfs, &fp)) != 0) 156 goto bad; 157 158 pfs->pfs_mode = S_IRUSR|S_IWUSR; 159 switch (fp->f_type) { 160 case DTYPE_VNODE: 161 vxp = (struct vnode *)fp->f_data; 162 vp->v_type = vxp->v_type; 163 break; 164 case DTYPE_PIPE: 165 vp->v_type = VFIFO; 166 break; 167 case DTYPE_SOCKET: 168 vp->v_type = VSOCK; 169 break; 170 default: 171 error = EOPNOTSUPP; 172 goto bad; 173 } 174 } 175 break; 176 177 case Pfile: /* /proc/N/file = -rw------- */ 178 case Pmem: /* /proc/N/mem = -rw------- */ 179 case Pregs: /* /proc/N/regs = -rw------- */ 180 case Pfpregs: /* /proc/N/fpregs = -rw------- */ 181 pfs->pfs_mode = S_IRUSR|S_IWUSR; 182 vp->v_type = VREG; 183 break; 184 185 case Pctl: /* /proc/N/ctl = --w------ */ 186 case Pnote: /* /proc/N/note = --w------ */ 187 case Pnotepg: /* /proc/N/notepg = --w------ */ 188 pfs->pfs_mode = S_IWUSR; 189 vp->v_type = VREG; 190 break; 191 192 case Pmap: /* /proc/N/map = -r--r--r-- */ 193 case Pmaps: /* /proc/N/maps = -r--r--r-- */ 194 case Pstatus: /* /proc/N/status = -r--r--r-- */ 195 case Pcmdline: /* /proc/N/cmdline = -r--r--r-- */ 196 case Pmeminfo: /* /proc/meminfo = -r--r--r-- */ 197 case Pcpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 198 case Puptime: /* /proc/uptime = -r--r--r-- */ 199 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 200 vp->v_type = VREG; 201 break; 202 203 #ifdef __HAVE_PROCFS_MACHDEP 204 PROCFS_MACHDEP_NODETYPE_CASES 205 procfs_machdep_allocvp(vp); 206 break; 207 #endif 208 209 default: 210 panic("procfs_allocvp"); 211 } 212 213 procfs_hashins(pfs); 214 uvm_vnp_setsize(vp, 0); 215 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 216 217 *vpp = vp; 218 return (0); 219 220 bad: 221 FREE(pfs, M_TEMP); 222 ungetnewvnode(vp); 223 return (error); 224 } 225 226 int 227 procfs_freevp(vp) 228 struct vnode *vp; 229 { 230 struct pfsnode *pfs = VTOPFS(vp); 231 232 procfs_hashrem(pfs); 233 234 FREE(vp->v_data, M_TEMP); 235 vp->v_data = 0; 236 return (0); 237 } 238 239 int 240 procfs_rw(v) 241 void *v; 242 { 243 struct vop_read_args *ap = v; 244 struct vnode *vp = ap->a_vp; 245 struct uio *uio = ap->a_uio; 246 struct proc *curp = uio->uio_procp; 247 struct pfsnode *pfs = VTOPFS(vp); 248 struct lwp *l; 249 struct proc *p; 250 251 p = PFIND(pfs->pfs_pid); 252 if (p == 0) 253 return (EINVAL); 254 255 /* XXX NJWLWP 256 * The entire procfs interface needs work to be useful to 257 * a process with multiple LWPs. For the moment, we'll 258 * just kluge this and fail on others. 259 */ 260 l = proc_representative_lwp(p); 261 262 switch (pfs->pfs_type) { 263 case Pregs: 264 case Pfpregs: 265 case Pmem: 266 #if defined(__HAVE_PROCFS_MACHDEP) && defined(PROCFS_MACHDEP_PROTECT_CASES) 267 PROCFS_MACHDEP_PROTECT_CASES 268 #endif 269 /* 270 * Do not allow init to be modified while in secure mode; it 271 * could be duped into changing the security level. 272 */ 273 if (uio->uio_rw == UIO_WRITE && 274 p == initproc && securelevel > -1) 275 return (EPERM); 276 break; 277 278 default: 279 break; 280 } 281 282 switch (pfs->pfs_type) { 283 case Pnote: 284 case Pnotepg: 285 return (procfs_donote(curp, p, pfs, uio)); 286 287 case Pregs: 288 return (procfs_doregs(curp, l, pfs, uio)); 289 290 case Pfpregs: 291 return (procfs_dofpregs(curp, l, pfs, uio)); 292 293 case Pctl: 294 return (procfs_doctl(curp, l, pfs, uio)); 295 296 case Pstatus: 297 return (procfs_dostatus(curp, l, pfs, uio)); 298 299 case Pmap: 300 return (procfs_domap(curp, p, pfs, uio, 0)); 301 302 case Pmaps: 303 return (procfs_domap(curp, p, pfs, uio, 1)); 304 305 case Pmem: 306 return (procfs_domem(curp, p, pfs, uio)); 307 308 case Pcmdline: 309 return (procfs_docmdline(curp, p, pfs, uio)); 310 311 case Pmeminfo: 312 return (procfs_domeminfo(curp, p, pfs, uio)); 313 314 case Pcpuinfo: 315 return (procfs_docpuinfo(curp, p, pfs, uio)); 316 317 case Pfd: 318 return (procfs_dofd(curp, p, pfs, uio)); 319 320 case Puptime: 321 return (procfs_douptime(curp, p, pfs, uio)); 322 323 #ifdef __HAVE_PROCFS_MACHDEP 324 PROCFS_MACHDEP_NODETYPE_CASES 325 return (procfs_machdep_rw(curp, l, pfs, uio)); 326 #endif 327 328 default: 329 return (EOPNOTSUPP); 330 } 331 } 332 333 /* 334 * Get a string from userland into (buf). Strip a trailing 335 * nl character (to allow easy access from the shell). 336 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 337 * will automatically add a nul char at the end. 338 * 339 * Returns 0 on success or the following errors 340 * 341 * EINVAL: file offset is non-zero. 342 * EMSGSIZE: message is longer than kernel buffer 343 * EFAULT: user i/o buffer is not addressable 344 */ 345 int 346 vfs_getuserstr(uio, buf, buflenp) 347 struct uio *uio; 348 char *buf; 349 int *buflenp; 350 { 351 int xlen; 352 int error; 353 354 if (uio->uio_offset != 0) 355 return (EINVAL); 356 357 xlen = *buflenp; 358 359 /* must be able to read the whole string in one go */ 360 if (xlen < uio->uio_resid) 361 return (EMSGSIZE); 362 xlen = uio->uio_resid; 363 364 if ((error = uiomove(buf, xlen, uio)) != 0) 365 return (error); 366 367 /* allow multiple writes without seeks */ 368 uio->uio_offset = 0; 369 370 /* cleanup string and remove trailing newline */ 371 buf[xlen] = '\0'; 372 xlen = strlen(buf); 373 if (xlen > 0 && buf[xlen-1] == '\n') 374 buf[--xlen] = '\0'; 375 *buflenp = xlen; 376 377 return (0); 378 } 379 380 const vfs_namemap_t * 381 vfs_findname(nm, buf, buflen) 382 const vfs_namemap_t *nm; 383 const char *buf; 384 int buflen; 385 { 386 387 for (; nm->nm_name; nm++) 388 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 389 return (nm); 390 391 return (0); 392 } 393 394 /* 395 * Initialize pfsnode hash table. 396 */ 397 void 398 procfs_hashinit() 399 { 400 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 401 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 402 M_WAITOK, &pfs_ihash); 403 simple_lock_init(&pfs_hash_slock); 404 } 405 406 void 407 procfs_hashreinit() 408 { 409 struct pfsnode *pp; 410 struct pfs_hashhead *oldhash, *hash; 411 u_long i, oldmask, mask, val; 412 413 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, 414 &mask); 415 416 simple_lock(&pfs_hash_slock); 417 oldhash = pfs_hashtbl; 418 oldmask = pfs_ihash; 419 pfs_hashtbl = hash; 420 pfs_ihash = mask; 421 for (i = 0; i <= oldmask; i++) { 422 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { 423 LIST_REMOVE(pp, pfs_hash); 424 val = PFSPIDHASH(pp->pfs_pid); 425 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash); 426 } 427 } 428 simple_unlock(&pfs_hash_slock); 429 hashdone(oldhash, M_UFSMNT); 430 } 431 432 /* 433 * Free pfsnode hash table. 434 */ 435 void 436 procfs_hashdone() 437 { 438 hashdone(pfs_hashtbl, M_UFSMNT); 439 } 440 441 struct vnode * 442 procfs_hashget(pid, type, fd, mp) 443 pid_t pid; 444 pfstype type; 445 int fd; 446 struct mount *mp; 447 { 448 struct pfs_hashhead *ppp; 449 struct pfsnode *pp; 450 struct vnode *vp; 451 452 loop: 453 simple_lock(&pfs_hash_slock); 454 ppp = &pfs_hashtbl[PFSPIDHASH(pid)]; 455 LIST_FOREACH(pp, ppp, pfs_hash) { 456 vp = PFSTOV(pp); 457 if (pid == pp->pfs_pid && pp->pfs_type == type && 458 pp->pfs_fd == fd && vp->v_mount == mp) { 459 simple_lock(&vp->v_interlock); 460 simple_unlock(&pfs_hash_slock); 461 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 462 goto loop; 463 return (vp); 464 } 465 } 466 simple_unlock(&pfs_hash_slock); 467 return (NULL); 468 } 469 470 /* 471 * Insert the pfsnode into the hash table and lock it. 472 */ 473 void 474 procfs_hashins(pp) 475 struct pfsnode *pp; 476 { 477 struct pfs_hashhead *ppp; 478 479 /* lock the pfsnode, then put it on the appropriate hash list */ 480 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 481 482 simple_lock(&pfs_hash_slock); 483 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)]; 484 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 485 simple_unlock(&pfs_hash_slock); 486 } 487 488 /* 489 * Remove the pfsnode from the hash table. 490 */ 491 void 492 procfs_hashrem(pp) 493 struct pfsnode *pp; 494 { 495 simple_lock(&pfs_hash_slock); 496 LIST_REMOVE(pp, pfs_hash); 497 simple_unlock(&pfs_hash_slock); 498 } 499 500 void 501 procfs_revoke_vnodes(p, arg) 502 struct proc *p; 503 void *arg; 504 { 505 struct pfsnode *pfs, *pnext; 506 struct vnode *vp; 507 struct mount *mp = (struct mount *)arg; 508 struct pfs_hashhead *ppp; 509 510 if (!(p->p_flag & P_SUGID)) 511 return; 512 513 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)]; 514 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) { 515 vp = PFSTOV(pfs); 516 pnext = LIST_NEXT(pfs, pfs_hash); 517 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 518 vp->v_mount == mp) 519 VOP_REVOKE(vp, REVOKEALL); 520 } 521 } 522 523 int 524 procfs_getfp(pfs, fp) 525 struct pfsnode *pfs; 526 struct file **fp; 527 { 528 struct proc *p = PFIND(pfs->pfs_pid); 529 530 if (p == NULL) 531 return ESRCH; 532 533 if (pfs->pfs_fd == -1) 534 return EINVAL; 535 536 if ((*fp = p->p_fd->fd_ofiles[pfs->pfs_fd]) == NULL) 537 return EBADF; 538 return 0; 539 } 540
Indexes created Mon Sep 22 21:09:42 GMT 2025