procfs_subr.c revision 1.45
1 /* $NetBSD: procfs_subr.c,v 1.45 2003/02/03 22:29:07 jdolecek 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 1.45 2003/02/03 22:29:07 jdolecek 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 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 199 vp->v_type = VREG; 200 break; 201 202 #ifdef __HAVE_PROCFS_MACHDEP 203 PROCFS_MACHDEP_NODETYPE_CASES 204 procfs_machdep_allocvp(vp); 205 break; 206 #endif 207 208 default: 209 panic("procfs_allocvp"); 210 } 211 212 procfs_hashins(pfs); 213 uvm_vnp_setsize(vp, 0); 214 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 215 216 *vpp = vp; 217 return (0); 218 219 bad: 220 FREE(pfs, M_TEMP); 221 ungetnewvnode(vp); 222 return (error); 223 } 224 225 int 226 procfs_freevp(vp) 227 struct vnode *vp; 228 { 229 struct pfsnode *pfs = VTOPFS(vp); 230 231 procfs_hashrem(pfs); 232 233 FREE(vp->v_data, M_TEMP); 234 vp->v_data = 0; 235 return (0); 236 } 237 238 int 239 procfs_rw(v) 240 void *v; 241 { 242 struct vop_read_args *ap = v; 243 struct vnode *vp = ap->a_vp; 244 struct uio *uio = ap->a_uio; 245 struct proc *curp = uio->uio_procp; 246 struct pfsnode *pfs = VTOPFS(vp); 247 struct lwp *l; 248 struct proc *p; 249 250 p = PFIND(pfs->pfs_pid); 251 if (p == 0) 252 return (EINVAL); 253 254 /* XXX NJWLWP 255 * The entire procfs interface needs work to be useful to 256 * a process with multiple LWPs. For the moment, we'll 257 * just kluge this and fail on others. 258 */ 259 l = proc_representative_lwp(p); 260 261 switch (pfs->pfs_type) { 262 case Pregs: 263 case Pfpregs: 264 case Pmem: 265 #if defined(__HAVE_PROCFS_MACHDEP) && defined(PROCFS_MACHDEP_PROTECT_CASES) 266 PROCFS_MACHDEP_PROTECT_CASES 267 #endif 268 /* 269 * Do not allow init to be modified while in secure mode; it 270 * could be duped into changing the security level. 271 */ 272 if (uio->uio_rw == UIO_WRITE && 273 p == initproc && securelevel > -1) 274 return (EPERM); 275 break; 276 277 default: 278 break; 279 } 280 281 switch (pfs->pfs_type) { 282 case Pnote: 283 case Pnotepg: 284 return (procfs_donote(curp, p, pfs, uio)); 285 286 case Pregs: 287 return (procfs_doregs(curp, l, pfs, uio)); 288 289 case Pfpregs: 290 return (procfs_dofpregs(curp, l, pfs, uio)); 291 292 case Pctl: 293 return (procfs_doctl(curp, l, pfs, uio)); 294 295 case Pstatus: 296 return (procfs_dostatus(curp, l, pfs, uio)); 297 298 case Pmap: 299 return (procfs_domap(curp, p, pfs, uio, 0)); 300 301 case Pmaps: 302 return (procfs_domap(curp, p, pfs, uio, 1)); 303 304 case Pmem: 305 return (procfs_domem(curp, p, pfs, uio)); 306 307 case Pcmdline: 308 return (procfs_docmdline(curp, p, pfs, uio)); 309 310 case Pmeminfo: 311 return (procfs_domeminfo(curp, p, pfs, uio)); 312 313 case Pcpuinfo: 314 return (procfs_docpuinfo(curp, p, pfs, uio)); 315 316 case Pfd: 317 return (procfs_dofd(curp, p, pfs, uio)); 318 319 #ifdef __HAVE_PROCFS_MACHDEP 320 PROCFS_MACHDEP_NODETYPE_CASES 321 return (procfs_machdep_rw(curp, l, pfs, uio)); 322 #endif 323 324 default: 325 return (EOPNOTSUPP); 326 } 327 } 328 329 /* 330 * Get a string from userland into (buf). Strip a trailing 331 * nl character (to allow easy access from the shell). 332 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 333 * will automatically add a nul char at the end. 334 * 335 * Returns 0 on success or the following errors 336 * 337 * EINVAL: file offset is non-zero. 338 * EMSGSIZE: message is longer than kernel buffer 339 * EFAULT: user i/o buffer is not addressable 340 */ 341 int 342 vfs_getuserstr(uio, buf, buflenp) 343 struct uio *uio; 344 char *buf; 345 int *buflenp; 346 { 347 int xlen; 348 int error; 349 350 if (uio->uio_offset != 0) 351 return (EINVAL); 352 353 xlen = *buflenp; 354 355 /* must be able to read the whole string in one go */ 356 if (xlen < uio->uio_resid) 357 return (EMSGSIZE); 358 xlen = uio->uio_resid; 359 360 if ((error = uiomove(buf, xlen, uio)) != 0) 361 return (error); 362 363 /* allow multiple writes without seeks */ 364 uio->uio_offset = 0; 365 366 /* cleanup string and remove trailing newline */ 367 buf[xlen] = '\0'; 368 xlen = strlen(buf); 369 if (xlen > 0 && buf[xlen-1] == '\n') 370 buf[--xlen] = '\0'; 371 *buflenp = xlen; 372 373 return (0); 374 } 375 376 const vfs_namemap_t * 377 vfs_findname(nm, buf, buflen) 378 const vfs_namemap_t *nm; 379 const char *buf; 380 int buflen; 381 { 382 383 for (; nm->nm_name; nm++) 384 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 385 return (nm); 386 387 return (0); 388 } 389 390 /* 391 * Initialize pfsnode hash table. 392 */ 393 void 394 procfs_hashinit() 395 { 396 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 397 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 398 M_WAITOK, &pfs_ihash); 399 simple_lock_init(&pfs_hash_slock); 400 } 401 402 void 403 procfs_hashreinit() 404 { 405 struct pfsnode *pp; 406 struct pfs_hashhead *oldhash, *hash; 407 u_long i, oldmask, mask, val; 408 409 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, 410 &mask); 411 412 simple_lock(&pfs_hash_slock); 413 oldhash = pfs_hashtbl; 414 oldmask = pfs_ihash; 415 pfs_hashtbl = hash; 416 pfs_ihash = mask; 417 for (i = 0; i <= oldmask; i++) { 418 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { 419 LIST_REMOVE(pp, pfs_hash); 420 val = PFSPIDHASH(pp->pfs_pid); 421 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash); 422 } 423 } 424 simple_unlock(&pfs_hash_slock); 425 hashdone(oldhash, M_UFSMNT); 426 } 427 428 /* 429 * Free pfsnode hash table. 430 */ 431 void 432 procfs_hashdone() 433 { 434 hashdone(pfs_hashtbl, M_UFSMNT); 435 } 436 437 struct vnode * 438 procfs_hashget(pid, type, fd, mp) 439 pid_t pid; 440 pfstype type; 441 int fd; 442 struct mount *mp; 443 { 444 struct pfs_hashhead *ppp; 445 struct pfsnode *pp; 446 struct vnode *vp; 447 448 loop: 449 simple_lock(&pfs_hash_slock); 450 ppp = &pfs_hashtbl[PFSPIDHASH(pid)]; 451 LIST_FOREACH(pp, ppp, pfs_hash) { 452 vp = PFSTOV(pp); 453 if (pid == pp->pfs_pid && pp->pfs_type == type && 454 pp->pfs_fd == fd && vp->v_mount == mp) { 455 simple_lock(&vp->v_interlock); 456 simple_unlock(&pfs_hash_slock); 457 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 458 goto loop; 459 return (vp); 460 } 461 } 462 simple_unlock(&pfs_hash_slock); 463 return (NULL); 464 } 465 466 /* 467 * Insert the pfsnode into the hash table and lock it. 468 */ 469 void 470 procfs_hashins(pp) 471 struct pfsnode *pp; 472 { 473 struct pfs_hashhead *ppp; 474 475 /* lock the pfsnode, then put it on the appropriate hash list */ 476 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 477 478 simple_lock(&pfs_hash_slock); 479 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)]; 480 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 481 simple_unlock(&pfs_hash_slock); 482 } 483 484 /* 485 * Remove the pfsnode from the hash table. 486 */ 487 void 488 procfs_hashrem(pp) 489 struct pfsnode *pp; 490 { 491 simple_lock(&pfs_hash_slock); 492 LIST_REMOVE(pp, pfs_hash); 493 simple_unlock(&pfs_hash_slock); 494 } 495 496 void 497 procfs_revoke_vnodes(p, arg) 498 struct proc *p; 499 void *arg; 500 { 501 struct pfsnode *pfs, *pnext; 502 struct vnode *vp; 503 struct mount *mp = (struct mount *)arg; 504 struct pfs_hashhead *ppp; 505 506 if (!(p->p_flag & P_SUGID)) 507 return; 508 509 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)]; 510 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) { 511 vp = PFSTOV(pfs); 512 pnext = LIST_NEXT(pfs, pfs_hash); 513 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 514 vp->v_mount == mp) 515 VOP_REVOKE(vp, REVOKEALL); 516 } 517 } 518 519 int 520 procfs_getfp(pfs, fp) 521 struct pfsnode *pfs; 522 struct file **fp; 523 { 524 struct proc *p = PFIND(pfs->pfs_pid); 525 526 if (p == NULL) 527 return ESRCH; 528 529 if (pfs->pfs_fd == -1) 530 return EINVAL; 531 532 if ((*fp = p->p_fd->fd_ofiles[pfs->pfs_fd]) == NULL) 533 return EBADF; 534 return 0; 535 } 536
Indexes created Tue Sep 23 14:10:03 GMT 2025