procfs_subr.c revision 1.36.2.7
1 /* $NetBSD: procfs_subr.c,v 1.36.2.7 2002/04/01 21:31:35 nathanw 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 1.36.2.7 2002/04/01 21:31:35 nathanw 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 55 #include <miscfs/procfs/procfs.h> 56 57 void procfs_hashins __P((struct pfsnode *)); 58 void procfs_hashrem __P((struct pfsnode *)); 59 struct vnode *procfs_hashget __P((pid_t, pfstype, struct mount *)); 60 61 LIST_HEAD(pfs_hashhead, pfsnode) *pfs_hashtbl; 62 u_long pfs_ihash; /* size of hash table - 1 */ 63 #define PFSPIDHASH(pid) ((pid) & pfs_ihash) 64 65 struct lock pfs_hashlock; 66 struct simplelock pfs_hash_slock; 67 68 #define ISSET(t, f) ((t) & (f)) 69 70 /* 71 * allocate a pfsnode/vnode pair. the vnode is 72 * referenced, and locked. 73 * 74 * the pid, pfs_type, and mount point uniquely 75 * identify a pfsnode. the mount point is needed 76 * because someone might mount this filesystem 77 * twice. 78 * 79 * all pfsnodes are maintained on a singly-linked 80 * list. new nodes are only allocated when they cannot 81 * be found on this list. entries on the list are 82 * removed when the vfs reclaim entry is called. 83 * 84 * a single lock is kept for the entire list. this is 85 * needed because the getnewvnode() function can block 86 * waiting for a vnode to become free, in which case there 87 * may be more than one process trying to get the same 88 * vnode. this lock is only taken if we are going to 89 * call getnewvnode, since the kernel itself is single-threaded. 90 * 91 * if an entry is found on the list, then call vget() to 92 * take a reference. this is done because there may be 93 * zero references to it and so it needs to removed from 94 * the vnode free list. 95 */ 96 int 97 procfs_allocvp(mp, vpp, pid, pfs_type) 98 struct mount *mp; 99 struct vnode **vpp; 100 long pid; 101 pfstype pfs_type; 102 { 103 struct pfsnode *pfs; 104 struct vnode *vp; 105 int error; 106 107 do { 108 if ((*vpp = procfs_hashget(pid, pfs_type, mp)) != NULL) 109 return (0); 110 } while (lockmgr(&pfs_hashlock, LK_EXCLUSIVE|LK_SLEEPFAIL, 0)); 111 112 if ((error = getnewvnode(VT_PROCFS, mp, procfs_vnodeop_p, vpp)) != 0) { 113 *vpp = NULL; 114 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 115 return (error); 116 } 117 vp = *vpp; 118 119 MALLOC(pfs, void *, sizeof(struct pfsnode), M_TEMP, M_WAITOK); 120 vp->v_data = pfs; 121 122 pfs->pfs_pid = (pid_t) pid; 123 pfs->pfs_type = pfs_type; 124 pfs->pfs_vnode = vp; 125 pfs->pfs_flags = 0; 126 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type); 127 128 switch (pfs_type) { 129 case Proot: /* /proc = dr-xr-xr-x */ 130 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 131 vp->v_type = VDIR; 132 vp->v_flag = VROOT; 133 break; 134 135 case Pcurproc: /* /proc/curproc = lr-xr-xr-x */ 136 case Pself: /* /proc/self = lr-xr-xr-x */ 137 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 138 vp->v_type = VLNK; 139 break; 140 141 case Pproc: /* /proc/N = dr-xr-xr-x */ 142 pfs->pfs_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 143 vp->v_type = VDIR; 144 break; 145 146 case Pfile: /* /proc/N/file = -rw------- */ 147 case Pmem: /* /proc/N/mem = -rw------- */ 148 case Pregs: /* /proc/N/regs = -rw------- */ 149 case Pfpregs: /* /proc/N/fpregs = -rw------- */ 150 pfs->pfs_mode = S_IRUSR|S_IWUSR; 151 vp->v_type = VREG; 152 break; 153 154 case Pctl: /* /proc/N/ctl = --w------ */ 155 case Pnote: /* /proc/N/note = --w------ */ 156 case Pnotepg: /* /proc/N/notepg = --w------ */ 157 pfs->pfs_mode = S_IWUSR; 158 vp->v_type = VREG; 159 break; 160 161 case Pmap: /* /proc/N/map = -r--r--r-- */ 162 case Pmaps: /* /proc/N/maps = -r--r--r-- */ 163 case Pstatus: /* /proc/N/status = -r--r--r-- */ 164 case Pcmdline: /* /proc/N/cmdline = -r--r--r-- */ 165 case Pmeminfo: /* /proc/meminfo = -r--r--r-- */ 166 case Pcpuinfo: /* /proc/cpuinfo = -r--r--r-- */ 167 pfs->pfs_mode = S_IRUSR|S_IRGRP|S_IROTH; 168 vp->v_type = VREG; 169 break; 170 171 #ifdef __HAVE_PROCFS_MACHDEP 172 PROCFS_MACHDEP_NODETYPE_CASES 173 procfs_machdep_allocvp(vp); 174 break; 175 #endif 176 177 default: 178 panic("procfs_allocvp"); 179 } 180 181 procfs_hashins(pfs); 182 uvm_vnp_setsize(vp, 0); 183 lockmgr(&pfs_hashlock, LK_RELEASE, NULL); 184 185 return (error); 186 } 187 188 int 189 procfs_freevp(vp) 190 struct vnode *vp; 191 { 192 struct pfsnode *pfs = VTOPFS(vp); 193 194 procfs_hashrem(pfs); 195 196 FREE(vp->v_data, M_TEMP); 197 vp->v_data = 0; 198 return (0); 199 } 200 201 int 202 procfs_rw(v) 203 void *v; 204 { 205 struct vop_read_args *ap = v; 206 struct vnode *vp = ap->a_vp; 207 struct uio *uio = ap->a_uio; 208 struct proc *curp = uio->uio_procp; 209 struct pfsnode *pfs = VTOPFS(vp); 210 struct lwp *l; 211 struct proc *p; 212 213 p = PFIND(pfs->pfs_pid); 214 if (p == 0) 215 return (EINVAL); 216 217 /* XXX NJWLWP 218 * The entire procfs interface needs work to be useful to 219 * a process with multiple LWPs. For the moment, we'll 220 * just kluge this and fail on others. 221 */ 222 l = proc_representative_lwp(p); 223 224 switch (pfs->pfs_type) { 225 case Pregs: 226 case Pfpregs: 227 case Pmem: 228 #if defined(__HAVE_PROCFS_MACHDEP) && defined(PROCFS_MACHDEP_PROTECT_CASES) 229 PROCFS_MACHDEP_PROTECT_CASES 230 #endif 231 /* 232 * Do not allow init to be modified while in secure mode; it 233 * could be duped into changing the security level. 234 */ 235 if (uio->uio_rw == UIO_WRITE && 236 p == initproc && securelevel > -1) 237 return (EPERM); 238 break; 239 240 default: 241 break; 242 } 243 244 switch (pfs->pfs_type) { 245 case Pnote: 246 case Pnotepg: 247 return (procfs_donote(curp, p, pfs, uio)); 248 249 case Pregs: 250 return (procfs_doregs(curp, l, pfs, uio)); 251 252 case Pfpregs: 253 return (procfs_dofpregs(curp, l, pfs, uio)); 254 255 case Pctl: 256 return (procfs_doctl(curp, l, pfs, uio)); 257 258 case Pstatus: 259 return (procfs_dostatus(curp, l, pfs, uio)); 260 261 case Pmap: 262 return (procfs_domap(curp, p, pfs, uio, 0)); 263 264 case Pmaps: 265 return (procfs_domap(curp, p, pfs, uio, 1)); 266 267 case Pmem: 268 return (procfs_domem(curp, p, pfs, uio)); 269 270 case Pcmdline: 271 return (procfs_docmdline(curp, p, pfs, uio)); 272 273 case Pmeminfo: 274 return (procfs_domeminfo(curp, p, pfs, uio)); 275 276 case Pcpuinfo: 277 return (procfs_docpuinfo(curp, p, pfs, uio)); 278 279 #ifdef __HAVE_PROCFS_MACHDEP 280 PROCFS_MACHDEP_NODETYPE_CASES 281 return (procfs_machdep_rw(curp, l, pfs, uio)); 282 #endif 283 284 default: 285 return (EOPNOTSUPP); 286 } 287 } 288 289 /* 290 * Get a string from userland into (buf). Strip a trailing 291 * nl character (to allow easy access from the shell). 292 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr 293 * will automatically add a nul char at the end. 294 * 295 * Returns 0 on success or the following errors 296 * 297 * EINVAL: file offset is non-zero. 298 * EMSGSIZE: message is longer than kernel buffer 299 * EFAULT: user i/o buffer is not addressable 300 */ 301 int 302 vfs_getuserstr(uio, buf, buflenp) 303 struct uio *uio; 304 char *buf; 305 int *buflenp; 306 { 307 int xlen; 308 int error; 309 310 if (uio->uio_offset != 0) 311 return (EINVAL); 312 313 xlen = *buflenp; 314 315 /* must be able to read the whole string in one go */ 316 if (xlen < uio->uio_resid) 317 return (EMSGSIZE); 318 xlen = uio->uio_resid; 319 320 if ((error = uiomove(buf, xlen, uio)) != 0) 321 return (error); 322 323 /* allow multiple writes without seeks */ 324 uio->uio_offset = 0; 325 326 /* cleanup string and remove trailing newline */ 327 buf[xlen] = '\0'; 328 xlen = strlen(buf); 329 if (xlen > 0 && buf[xlen-1] == '\n') 330 buf[--xlen] = '\0'; 331 *buflenp = xlen; 332 333 return (0); 334 } 335 336 const vfs_namemap_t * 337 vfs_findname(nm, buf, buflen) 338 const vfs_namemap_t *nm; 339 const char *buf; 340 int buflen; 341 { 342 343 for (; nm->nm_name; nm++) 344 if (memcmp(buf, nm->nm_name, buflen+1) == 0) 345 return (nm); 346 347 return (0); 348 } 349 350 /* 351 * Initialize pfsnode hash table. 352 */ 353 void 354 procfs_hashinit() 355 { 356 lockinit(&pfs_hashlock, PINOD, "pfs_hashlock", 0, 0); 357 pfs_hashtbl = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, 358 M_WAITOK, &pfs_ihash); 359 simple_lock_init(&pfs_hash_slock); 360 } 361 362 void 363 procfs_hashreinit() 364 { 365 struct pfsnode *pp; 366 struct pfs_hashhead *oldhash, *hash; 367 u_long oldmask, mask, val; 368 int i; 369 370 hash = hashinit(desiredvnodes / 4, HASH_LIST, M_UFSMNT, M_WAITOK, 371 &mask); 372 373 simple_lock(&pfs_hash_slock); 374 oldhash = pfs_hashtbl; 375 oldmask = pfs_ihash; 376 pfs_hashtbl = hash; 377 pfs_ihash = mask; 378 for (i = 0; i <= oldmask; i++) { 379 while ((pp = LIST_FIRST(&oldhash[i])) != NULL) { 380 LIST_REMOVE(pp, pfs_hash); 381 val = PFSPIDHASH(pp->pfs_pid); 382 LIST_INSERT_HEAD(&hash[val], pp, pfs_hash); 383 } 384 } 385 simple_unlock(&pfs_hash_slock); 386 hashdone(oldhash, M_UFSMNT); 387 } 388 389 /* 390 * Free pfsnode hash table. 391 */ 392 void 393 procfs_hashdone() 394 { 395 hashdone(pfs_hashtbl, M_UFSMNT); 396 } 397 398 struct vnode * 399 procfs_hashget(pid, type, mp) 400 pid_t pid; 401 pfstype type; 402 struct mount *mp; 403 { 404 struct pfs_hashhead *ppp; 405 struct pfsnode *pp; 406 struct vnode *vp; 407 408 loop: 409 simple_lock(&pfs_hash_slock); 410 ppp = &pfs_hashtbl[PFSPIDHASH(pid)]; 411 LIST_FOREACH(pp, ppp, pfs_hash) { 412 vp = PFSTOV(pp); 413 if (pid == pp->pfs_pid && pp->pfs_type == type && 414 vp->v_mount == mp) { 415 simple_lock(&vp->v_interlock); 416 simple_unlock(&pfs_hash_slock); 417 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) 418 goto loop; 419 return (vp); 420 } 421 } 422 simple_unlock(&pfs_hash_slock); 423 return (NULL); 424 } 425 426 /* 427 * Insert the pfsnode into the hash table and lock it. 428 */ 429 void 430 procfs_hashins(pp) 431 struct pfsnode *pp; 432 { 433 struct pfs_hashhead *ppp; 434 435 /* lock the pfsnode, then put it on the appropriate hash list */ 436 lockmgr(&pp->pfs_vnode->v_lock, LK_EXCLUSIVE, (struct simplelock *)0); 437 438 simple_lock(&pfs_hash_slock); 439 ppp = &pfs_hashtbl[PFSPIDHASH(pp->pfs_pid)]; 440 LIST_INSERT_HEAD(ppp, pp, pfs_hash); 441 simple_unlock(&pfs_hash_slock); 442 } 443 444 /* 445 * Remove the pfsnode from the hash table. 446 */ 447 void 448 procfs_hashrem(pp) 449 struct pfsnode *pp; 450 { 451 simple_lock(&pfs_hash_slock); 452 LIST_REMOVE(pp, pfs_hash); 453 simple_unlock(&pfs_hash_slock); 454 } 455 456 void 457 procfs_revoke_vnodes(p, arg) 458 struct proc *p; 459 void *arg; 460 { 461 struct pfsnode *pfs, *pnext; 462 struct vnode *vp; 463 struct mount *mp = (struct mount *)arg; 464 struct pfs_hashhead *ppp; 465 466 if (!(p->p_flag & P_SUGID)) 467 return; 468 469 ppp = &pfs_hashtbl[PFSPIDHASH(p->p_pid)]; 470 for (pfs = LIST_FIRST(ppp); pfs; pfs = pnext) { 471 vp = PFSTOV(pfs); 472 pnext = LIST_NEXT(pfs, pfs_hash); 473 if (vp->v_usecount > 0 && pfs->pfs_pid == p->p_pid && 474 vp->v_mount == mp) 475 VOP_REVOKE(vp, REVOKEALL); 476 } 477 } 478
Indexes created Sun Sep 28 16:09:52 GMT 2025