procfs_subr.c revision 1.56
1 /* $NetBSD: procfs_subr.c,v 1.56 2003/06/29 22:31:46 fvdl 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 1.56 2003/06/29 22:31:46 fvdl 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 = S_IRUSR|S_IXUSR; 148 vp->v_type = VDIR; 149 } else { /* /proc/N/fd/M = [ps-]rw------- */ 150 struct file *fp; 151 struct vnode *vxp; 152 struct proc *pown; 153 154 /* XXX can procfs_getfp() ever fail here? */ 155 if ((error = procfs_getfp(pfs, &pown, &fp)) != 0) 156 goto bad; 157 FILE_USE(fp); 158 159 pfs->pfs_mode = S_IRUSR|S_IWUSR; 160 switch (fp->f_type) { 161 case DTYPE_VNODE: 162 vxp = (struct vnode *)fp->f_data; 163 164 /* 165 * We make symlinks for directories 166 * to avoid cycles. 167 */ 168 if (vxp->v_type == VDIR) 169 goto symlink; 170 vp->v_type = vxp->v_type; 171 break; 172 case DTYPE_PIPE: 173 vp->v_type = VFIFO; 174 break; 175 case DTYPE_SOCKET: 176 vp->v_type = VSOCK; 177 break; 178 case DTYPE_KQUEUE: 179 case DTYPE_MISC: 180 symlink: 181 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP| 182 S_IXGRP|S_IROTH|S_IXOTH; 183 vp->v_type = VLNK; 184 break; 185 default: 186 error = EOPNOTSUPP; 187 FILE_UNUSE(fp, pown); 188 goto bad; 189 } 190 FILE_UNUSE(fp, pown); 191 } 192 break; 193 194 case Pfile: /* /proc/N/file = -rw------- */ 195 case Pmem: /* /proc/N/mem = -rw------- */ 196 case Pregs: /* /proc/N/regs = -rw------- */ 197 case Pfpregs: /* /proc/N/fpregs = -rw------- */ 198 pfs->pfs_mode = S_IRUSR|S_IWUSR; 199 vp->v_type = VREG; 200 break; 201 202 case Pctl: /* /proc/N/ctl = --w------ */ 203 case Pnote: /* /proc/N/note = --w------ */ 204 case Pnotepg: /* /proc/N/notepg = --w------ */ 205 pfs->pfs_mode = S_IWUSR; 206 vp->v_type = VREG; 207 break; 208 209 case Pmap: /* /proc/N/map = -r--r--r-- */ 210 case Pmaps: /* /proc/N/maps = -r--r--r-- */ 211 case Pstatus: /* /proc/N/status = -r--r--r-- */ 212 case Pstat: /* /proc/N/stat = -r--r--r-- */ 213 case Pcmdline: /* /proc/N/cmdline = -r--r--r-- */ 214 case Pmeminfo: /* /proc/meminfo = -r--r--r-- */ 215 case Pcpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 216 case Puptime: /* /proc/uptime = -r--r--r-- */ 217 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 218 vp->v_type = VREG; 219 break; 220 221 #ifdef __HAVE_PROCFS_MACHDEP 222 PROCFS_MACHDEP_NODETYPE_CASES 223 procfs_machdep_allocvp(vp); 224 break; 225 #endif 226 227 default: 228 panic("procfs_allocvp"); 229 } 230 231 procfs_hashins(pfs); 232 uvm_vnp_setsize(vp, 0); 233 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 234 235 *vpp = vp; 236 return (0); 237 238 bad: 239 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 240 FREE(pfs, M_TEMP); 241 ungetnewvnode(vp); 242 return (error); 243 } 244 245 int 246 procfs_freevp(vp) 247 struct vnode *vp; 248 { 249 struct pfsnode *pfs = VTOPFS(vp); 250 251 procfs_hashrem(pfs); 252 253 FREE(vp->v_data, M_TEMP); 254 vp->v_data = 0; 255 return (0); 256 } 257 258 int 259 procfs_rw(v) 260 void *v; 261 { 262 struct vop_read_args *ap = v; 263 struct vnode *vp = ap->a_vp; 264 struct uio *uio = ap->a_uio; 265 struct proc *curp = uio->uio_procp; 266 struct pfsnode *pfs = VTOPFS(vp); 267 struct lwp *l; 268 struct proc *p; 269 270 p = PFIND(pfs->pfs_pid); 271 if (p == 0) 272 return (EINVAL); 273 274 /* XXX NJWLWP 275 * The entire procfs interface needs work to be useful to 276 * a process with multiple LWPs. For the moment, we'll 277 * just kluge this and fail on others. 278 */ 279 l = proc_representative_lwp(p); 280 281 switch (pfs->pfs_type) { 282 case Pregs: 283 case Pfpregs: 284 case Pmem: 285 #if defined(__HAVE_PROCFS_MACHDEP) && defined(PROCFS_MACHDEP_PROTECT_CASES) 286 PROCFS_MACHDEP_PROTECT_CASES 287 #endif 288 /* 289 * Do not allow init to be modified while in secure mode; it 290 * could be duped into changing the security level. 291 */ 292 if (uio->uio_rw == UIO_WRITE && 293 p == initproc && securelevel > -1) 294 return (EPERM); 295 break; 296 297 default: 298 break; 299 } 300 301 switch (pfs->pfs_type) { 302 case Pnote: 303 case Pnotepg: 304 return (procfs_donote(curp, p, pfs, uio)); 305 306 case Pregs: 307 return (procfs_doregs(curp, l, pfs, uio)); 308 309 case Pfpregs: 310 return (procfs_dofpregs(curp, l, pfs, uio)); 311 312 case Pctl: 313 return (procfs_doctl(curp, l, pfs, uio)); 314 315 case Pstatus: 316 return (procfs_dostatus(curp, l, pfs, uio)); 317 318 case Pstat: 319 return (procfs_do_pid_stat(curp, l, pfs, uio)); 320 321 case Pmap: 322 return (procfs_domap(curp, p, pfs, uio, 0)); 323 324 case Pmaps: 325 return (procfs_domap(curp, p, pfs, uio, 1)); 326 327 case Pmem: 328 return (procfs_domem(curp, p, pfs, uio)); 329 330 case Pcmdline: 331 return (procfs_docmdline(curp, p, pfs, uio)); 332 333 case Pmeminfo: 334 return (procfs_domeminfo(curp, p, pfs, uio)); 335 336 case Pcpuinfo: 337 return (procfs_docpuinfo(curp, p, pfs, uio)); 338 339 case Pfd: 340 return (procfs_dofd(curp, p, pfs, uio)); 341 342 case Puptime: 343 return (procfs_douptime(curp, p, pfs, uio)); 344 345 #ifdef __HAVE_PROCFS_MACHDEP 346 PROCFS_MACHDEP_NODETYPE_CASES 347 return (procfs_machdep_rw(curp, l, pfs, uio)); 348 #endif 349 350 default: 351 return (EOPNOTSUPP); 352 } 353 } 354 355 /* 356 * Get a string from userland into (buf). Strip a trailing 357 * nl character (to allow easy access from the shell). 358 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 359 * will automatically add a nul char at the end. 360 * 361 * Returns 0 on success or the following errors 362 * 363 * EINVAL: file offset is non-zero. 364 * EMSGSIZE: message is longer than kernel buffer 365 * EFAULT: user i/o buffer is not addressable 366 */ 367 int 368 vfs_getuserstr(uio, buf, buflenp) 369 struct uio *uio; 370 char *buf; 371 int *buflenp; 372 { 373 int xlen; 374 int error; 375 376 if (uio->uio_offset != 0) 377 return (EINVAL); 378 379 xlen = *buflenp; 380 381 /* must be able to read the whole string in one go */ 382 if (xlen < uio->uio_resid) 383 return (EMSGSIZE); 384 xlen = uio->uio_resid; 385 386 if ((error = uiomove(buf, xlen, uio)) != 0) 387 return (error); 388 389 /* allow multiple writes without seeks */ 390 uio->uio_offset = 0; 391 392 /* cleanup string and remove trailing newline */ 393 buf[xlen] = '\0'; 394 xlen = strlen(buf); 395 if (xlen > 0 && buf[xlen-1] == '\n') 396 buf[--xlen] = '\0'; 397 *buflenp = xlen; 398 399 return (0); 400 } 401 402 const vfs_namemap_t * 403 vfs_findname(nm, buf, buflen) 404 const vfs_namemap_t *nm; 405 const char *buf; 406 int buflen; 407 { 408 409 for (; nm->nm_name; nm++) 410 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 411 return (nm); 412 413 return (0); 414 } 415 416 /* 417 * Initialize pfsnode hash table. 418 */ 419 void 420 procfs_hashinit() 421 { 422 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 423 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 424 M_WAITOK, &pfs_ihash); 425 simple_lock_init(&pfs_hash_slock); 426 } 427 428 void 429 procfs_hashreinit() 430 { 431 struct pfsnode *pp; 432 struct pfs_hashhead *oldhash, *hash; 433 u_long i, oldmask, mask, val; 434 435 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, 436 &mask); 437 438 simple_lock(&pfs_hash_slock); 439 oldhash = pfs_hashtbl; 440 oldmask = pfs_ihash; 441 pfs_hashtbl = hash; 442 pfs_ihash = mask; 443 for (i = 0; i <= oldmask; i++) { 444 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { 445 LIST_REMOVE(pp, pfs_hash); 446 val = PFSPIDHASH(pp->pfs_pid); 447 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash); 448 } 449 } 450 simple_unlock(&pfs_hash_slock); 451 hashdone(oldhash, M_UFSMNT); 452 } 453 454 /* 455 * Free pfsnode hash table. 456 */ 457 void 458 procfs_hashdone() 459 { 460 hashdone(pfs_hashtbl, M_UFSMNT); 461 } 462 463 struct vnode * 464 procfs_hashget(pid, type, fd, mp) 465 pid_t pid; 466 pfstype type; 467 int fd; 468 struct mount *mp; 469 { 470 struct pfs_hashhead *ppp; 471 struct pfsnode *pp; 472 struct vnode *vp; 473 474 loop: 475 simple_lock(&pfs_hash_slock); 476 ppp = &pfs_hashtbl[PFSPIDHASH(pid)]; 477 LIST_FOREACH(pp, ppp, pfs_hash) { 478 vp = PFSTOV(pp); 479 if (pid == pp->pfs_pid && pp->pfs_type == type && 480 pp->pfs_fd == fd && vp->v_mount == mp) { 481 simple_lock(&vp->v_interlock); 482 simple_unlock(&pfs_hash_slock); 483 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 484 goto loop; 485 return (vp); 486 } 487 } 488 simple_unlock(&pfs_hash_slock); 489 return (NULL); 490 } 491 492 /* 493 * Insert the pfsnode into the hash table and lock it. 494 */ 495 void 496 procfs_hashins(pp) 497 struct pfsnode *pp; 498 { 499 struct pfs_hashhead *ppp; 500 501 /* lock the pfsnode, then put it on the appropriate hash list */ 502 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 503 504 simple_lock(&pfs_hash_slock); 505 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)]; 506 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 507 simple_unlock(&pfs_hash_slock); 508 } 509 510 /* 511 * Remove the pfsnode from the hash table. 512 */ 513 void 514 procfs_hashrem(pp) 515 struct pfsnode *pp; 516 { 517 simple_lock(&pfs_hash_slock); 518 LIST_REMOVE(pp, pfs_hash); 519 simple_unlock(&pfs_hash_slock); 520 } 521 522 void 523 procfs_revoke_vnodes(p, arg) 524 struct proc *p; 525 void *arg; 526 { 527 struct pfsnode *pfs, *pnext; 528 struct vnode *vp; 529 struct mount *mp = (struct mount *)arg; 530 struct pfs_hashhead *ppp; 531 532 if (!(p->p_flag & P_SUGID)) 533 return; 534 535 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)]; 536 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) { 537 vp = PFSTOV(pfs); 538 pnext = LIST_NEXT(pfs, pfs_hash); 539 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 540 vp->v_mount == mp) 541 VOP_REVOKE(vp, REVOKEALL); 542 } 543 } 544 545 int 546 procfs_getfp(pfs, pown, fp) 547 struct pfsnode *pfs; 548 struct proc **pown; 549 struct file **fp; 550 { 551 struct proc *p = PFIND(pfs->pfs_pid); 552 553 if (p == NULL) 554 return ESRCH; 555 556 if (pfs->pfs_fd == -1) 557 return EINVAL; 558 559 if ((*fp = fd_getfile(p->p_fd, pfs->pfs_fd)) == NULL) 560 return EBADF; 561 562 *pown = p; 563 return 0; 564 } 565
Indexes created Mon Sep 22 13:09:51 GMT 2025