Annotation of sys/kern/kern_lkm.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: kern_lkm.c,v 1.43 2006/11/15 17:25:40 jmc Exp $ */
! 2: /* $NetBSD: kern_lkm.c,v 1.31 1996/03/31 21:40:27 christos Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1994 Christopher G. Demetriou
! 6: * Copyright (c) 1992 Terrence R. Lambert.
! 7: * All rights reserved.
! 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 Terrence R. Lambert.
! 20: * 4. The name Terrence R. Lambert may not be used to endorse or promote
! 21: * products derived from this software without specific prior written
! 22: * permission.
! 23: *
! 24: * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY
! 25: * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 27: * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE
! 28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 34: * SUCH DAMAGE.
! 35: */
! 36:
! 37: /*
! 38: * XXX it's not really safe to unload *any* of the types which are
! 39: * currently loadable; e.g. you could unload a syscall which was being
! 40: * blocked in, etc. In the long term, a solution should be come up
! 41: * with, but "not right now." -- cgd
! 42: */
! 43:
! 44: #include <sys/param.h>
! 45: #include <sys/systm.h>
! 46: #include <sys/ioctl.h>
! 47: #include <sys/tty.h>
! 48: #include <sys/file.h>
! 49: #include <sys/proc.h>
! 50: #include <sys/uio.h>
! 51: #include <sys/kernel.h>
! 52: #include <sys/vnode.h>
! 53: #include <sys/malloc.h>
! 54: #include <sys/mount.h>
! 55: #include <sys/exec.h>
! 56: #include <sys/syscallargs.h>
! 57: #include <sys/conf.h>
! 58:
! 59: #include <sys/lkm.h>
! 60: #include <sys/syscall.h>
! 61:
! 62: #include <uvm/uvm_extern.h>
! 63:
! 64: #ifdef DDB
! 65: #include <machine/db_machdep.h>
! 66: #include <ddb/db_sym.h>
! 67: #endif
! 68:
! 69: /* flags */
! 70: #define LKM_ALLOC 0x01
! 71: #define LKM_WANT 0x02
! 72: #define LKM_INIT 0x04
! 73:
! 74: #define LKMS_IDLE 0x00
! 75: #define LKMS_RESERVED 0x01
! 76: #define LKMS_LOADING 0x02
! 77: #define LKMS_LOADING_SYMS 0x03
! 78: #define LKMS_LOADED 0x04
! 79: #define LKMS_UNLOADING 0x08
! 80:
! 81: static int lkm_v = 0;
! 82: static int lkm_state = LKMS_IDLE;
! 83:
! 84: static TAILQ_HEAD(lkmods, lkm_table) lkmods; /* table of loaded modules */
! 85: static struct lkm_table *curp; /* global for in-progress ops */
! 86:
! 87: static struct lkm_table *lkmalloc(void);
! 88: static void lkmfree(struct lkm_table *);
! 89: static struct lkm_table *lkmlookup(int, char *, int *);
! 90: static void lkmunreserve(void);
! 91: static int _lkm_syscall(struct lkm_table *, int);
! 92: static int _lkm_vfs(struct lkm_table *, int);
! 93: static int _lkm_dev(struct lkm_table *, int);
! 94: static int _lkm_exec(struct lkm_table *, int);
! 95:
! 96: void lkminit(void);
! 97: int lkmexists(struct lkm_table *);
! 98:
! 99: void init_exec(void);
! 100:
! 101: void
! 102: lkminit(void)
! 103: {
! 104:
! 105: TAILQ_INIT(&lkmods);
! 106: lkm_v |= LKM_INIT;
! 107: }
! 108:
! 109: /*ARGSUSED*/
! 110: int
! 111: lkmopen(dev_t dev, int flag, int devtype, struct proc *p)
! 112: {
! 113: int error;
! 114:
! 115: if (minor(dev) != 0)
! 116: return (ENXIO);
! 117:
! 118: if (!(lkm_v & LKM_INIT))
! 119: lkminit();
! 120:
! 121: /*
! 122: * Use of the loadable kernel module device must be exclusive; we
! 123: * may try to remove this restriction later, but it's really no
! 124: * hardship.
! 125: */
! 126: while (lkm_v & LKM_ALLOC) {
! 127: if (flag & FNONBLOCK) /* don't hang */
! 128: return (EBUSY);
! 129: lkm_v |= LKM_WANT;
! 130: /*
! 131: * Sleep pending unlock; we use tsleep() to allow
! 132: * an alarm out of the open.
! 133: */
! 134: error = tsleep(&lkm_v, TTIPRI|PCATCH, "lkmopn", 0);
! 135: if (error)
! 136: return (error); /* leave LKM_WANT set -- no problem */
! 137: }
! 138: lkm_v |= LKM_ALLOC;
! 139:
! 140: return (0); /* pseudo-device open */
! 141: }
! 142:
! 143: /*
! 144: * Alocates new LKM table entry, fills module id, inserts in the list.
! 145: * Returns NULL on failure.
! 146: *
! 147: */
! 148: static struct lkm_table *
! 149: lkmalloc(void)
! 150: {
! 151: struct lkm_table *p, *ret = NULL;
! 152: int id = 0;
! 153:
! 154: MALLOC(ret, struct lkm_table *, sizeof(*ret), M_DEVBUF, M_WAITOK);
! 155: ret->refcnt = ret->depcnt = 0;
! 156: ret->sym_id = -1;
! 157: /*
! 158: * walk the list finding the first free id. as long as the list is
! 159: * kept sorted this is not too inefficient, which is why we insert in
! 160: * order below.
! 161: */
! 162: TAILQ_FOREACH(p, &lkmods, list) {
! 163: if (id == p->id)
! 164: id++;
! 165: else
! 166: break;
! 167: }
! 168: ret->id = id;
! 169: if (p == NULL) /* either first or last entry */
! 170: TAILQ_INSERT_TAIL(&lkmods, ret, list);
! 171: else
! 172: TAILQ_INSERT_BEFORE(p, ret, list);
! 173:
! 174: return ret;
! 175: }
! 176:
! 177: /*
! 178: * Frees the slot, decreases the number of modules.
! 179: */
! 180: static void
! 181: lkmfree(struct lkm_table *p)
! 182: {
! 183:
! 184: TAILQ_REMOVE(&lkmods, p, list);
! 185: free(p, M_DEVBUF);
! 186: curp = NULL;
! 187: }
! 188:
! 189: struct lkm_table *
! 190: lkm_list(struct lkm_table *p)
! 191: {
! 192:
! 193: if (p == NULL)
! 194: p = TAILQ_FIRST(&lkmods);
! 195: else
! 196: p = TAILQ_NEXT(p, list);
! 197:
! 198: return (p);
! 199: }
! 200:
! 201: static struct lkm_table *
! 202: lkmlookup(int i, char *name, int *error)
! 203: {
! 204: struct lkm_table *p = NULL;
! 205: char istr[MAXLKMNAME];
! 206:
! 207: /*
! 208: * p being NULL here implies the list is empty, so any lookup is
! 209: * invalid (name based or otherwise). Since the list of modules is
! 210: * kept sorted by id, lowest to highest, the id of the last entry
! 211: * will be the highest in use.
! 212: */
! 213: p = TAILQ_LAST(&lkmods, lkmods);
! 214: if (p == NULL || i > p->id) {
! 215: *error = EINVAL;
! 216: return NULL;
! 217: }
! 218:
! 219: if (i < 0) { /* unload by name */
! 220: /*
! 221: * Copy name and lookup id from all loaded
! 222: * modules. May fail.
! 223: */
! 224: *error = copyinstr(name, istr, MAXLKMNAME-1, NULL);
! 225: if (*error)
! 226: return NULL;
! 227: istr[MAXLKMNAME-1] = '\0';
! 228:
! 229: TAILQ_FOREACH(p, &lkmods, list) {
! 230: if (!strcmp(istr, p->private.lkm_any->lkm_name))
! 231: break;
! 232: }
! 233: } else
! 234: TAILQ_FOREACH(p, &lkmods, list)
! 235: if (i == p->id)
! 236: break;
! 237:
! 238: if (p == NULL)
! 239: *error = ENOENT;
! 240:
! 241: return p;
! 242: }
! 243:
! 244: /*
! 245: * Unreserve the memory associated with the current loaded module; done on
! 246: * a coerced close of the lkm device (close on premature exit of modload)
! 247: * or explicitly by modload as a result of a link failure.
! 248: */
! 249: static void
! 250: lkmunreserve(void)
! 251: {
! 252:
! 253: if (lkm_state == LKMS_IDLE)
! 254: return;
! 255:
! 256: #ifdef DDB
! 257: if (curp && curp->sym_id != -1)
! 258: db_del_symbol_table(curp->private.lkm_any->lkm_name);
! 259: #endif
! 260:
! 261: if (curp && curp->syms) {
! 262: uvm_km_free(kernel_map, (vaddr_t)curp->syms, curp->sym_size);
! 263: curp->syms = NULL;
! 264: }
! 265:
! 266: /*
! 267: * Actually unreserve the memory
! 268: */
! 269: if (curp && curp->area) {
! 270: uvm_km_free(kernel_map, curp->area, curp->size);
! 271: curp->area = 0;
! 272: }
! 273: lkm_state = LKMS_IDLE;
! 274: }
! 275:
! 276: int
! 277: lkmclose(dev_t dev, int flag, int mode, struct proc *p)
! 278: {
! 279:
! 280: if (minor(dev) != 0)
! 281: return (ENXIO);
! 282:
! 283: if (!(lkm_v & LKM_ALLOC))
! 284: return (EBADF);
! 285:
! 286: /* do this before waking the herd... */
! 287: if (curp != NULL && !curp->refcnt) {
! 288: /*
! 289: * If we close before setting used, we have aborted
! 290: * by way of error or by way of close-on-exit from
! 291: * a premature exit of "modload".
! 292: */
! 293: lkmunreserve();
! 294: lkmfree(curp);
! 295: }
! 296: lkm_v &= ~LKM_ALLOC;
! 297: wakeup(&lkm_v); /* thundering herd "problem" here */
! 298:
! 299: return (0);
! 300: }
! 301:
! 302: /*ARGSUSED*/
! 303: int
! 304: lkmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
! 305: {
! 306: int error = 0;
! 307:
! 308: if (securelevel > 0) {
! 309: switch (cmd) {
! 310: case LMSTAT:
! 311: break;
! 312: default:
! 313: return (EPERM);
! 314: }
! 315: }
! 316:
! 317: if (!(flags & FWRITE)) {
! 318: switch (cmd) {
! 319: case LMSTAT:
! 320: break;
! 321: default:
! 322: return (EACCES);
! 323: }
! 324: }
! 325:
! 326: switch (cmd) {
! 327: case LMRESERV:
! 328: case LMRESERV_O: {
! 329: struct lmc_resrv *resrvp = (struct lmc_resrv *)data;
! 330:
! 331: if ((curp = lkmalloc()) == NULL) {
! 332: error = ENOMEM;
! 333: break;
! 334: }
! 335: curp->ver = (cmd == LMRESERV) ? LKM_VERSION : LKM_OLDVERSION;
! 336: resrvp->slot = curp->id; /* return slot */
! 337:
! 338: /*
! 339: * Get memory for module
! 340: */
! 341: curp->size = resrvp->size;
! 342: curp->area = uvm_km_zalloc(kernel_map, curp->size);
! 343: curp->offset = 0;
! 344: resrvp->addr = curp->area;
! 345:
! 346: if (cmd == LMRESERV && resrvp->sym_size) {
! 347: curp->sym_size = resrvp->sym_size;
! 348: curp->sym_symsize = resrvp->sym_symsize;
! 349: curp->syms = (caddr_t)uvm_km_zalloc(kernel_map,
! 350: curp->sym_size);
! 351: curp->sym_offset = 0;
! 352: resrvp->sym_addr = curp->syms;
! 353: } else {
! 354: curp->sym_size = 0;
! 355: curp->syms = 0;
! 356: curp->sym_offset = 0;
! 357: if (cmd == LMRESERV)
! 358: resrvp->sym_addr = 0;
! 359: }
! 360: #ifdef LKM_DEBUG
! 361: printf("LKM: LMRESERV (actual = 0x%08lx)\n", curp->area);
! 362: printf("LKM: LMRESERV (syms = 0x%08x)\n", curp->syms);
! 363: printf("LKM: LMRESERV (adjusted = 0x%08lx)\n",
! 364: trunc_page(curp->area));
! 365: #endif /* LKM_DEBUG */
! 366:
! 367: lkm_state = LKMS_RESERVED;
! 368: break;
! 369: }
! 370:
! 371: case LMLOADBUF: {
! 372: struct lmc_loadbuf *loadbufp = (struct lmc_loadbuf *)data;
! 373:
! 374: if ((lkm_state != LKMS_RESERVED && lkm_state != LKMS_LOADING)
! 375: || loadbufp->cnt < 0
! 376: || loadbufp->cnt > MODIOBUF
! 377: || loadbufp->cnt > (curp->size - curp->offset)) {
! 378: error = ENOMEM;
! 379: break;
! 380: }
! 381:
! 382: /* copy in buffer full of data */
! 383: error = copyin(loadbufp->data,
! 384: (caddr_t)curp->area + curp->offset, loadbufp->cnt);
! 385: if (error)
! 386: break;
! 387:
! 388: if ((curp->offset + loadbufp->cnt) < curp->size)
! 389: lkm_state = LKMS_LOADING;
! 390: else
! 391: lkm_state = LKMS_LOADING_SYMS;
! 392:
! 393: curp->offset += loadbufp->cnt;
! 394: break;
! 395: }
! 396:
! 397: case LMLOADSYMS: {
! 398: struct lmc_loadbuf *loadbufp = (struct lmc_loadbuf *)data;
! 399:
! 400: if ((lkm_state != LKMS_LOADING &&
! 401: lkm_state != LKMS_LOADING_SYMS)
! 402: || loadbufp->cnt < 0
! 403: || loadbufp->cnt > MODIOBUF
! 404: || loadbufp->cnt > (curp->sym_size - curp->sym_offset)) {
! 405: error = ENOMEM;
! 406: break;
! 407: }
! 408:
! 409: /* copy in buffer full of data*/
! 410: error = copyin(loadbufp->data, curp->syms +
! 411: curp->sym_offset, loadbufp->cnt);
! 412: if (error)
! 413: break;
! 414:
! 415: if ((curp->sym_offset + loadbufp->cnt) < curp->sym_size)
! 416: lkm_state = LKMS_LOADING_SYMS;
! 417: else
! 418: lkm_state = LKMS_LOADED;
! 419:
! 420: curp->sym_offset += loadbufp->cnt;
! 421: break;
! 422: }
! 423:
! 424: case LMUNRESRV:
! 425: lkmunreserve();
! 426: if (curp)
! 427: lkmfree(curp);
! 428: break;
! 429:
! 430: case LMREADY:
! 431: switch (lkm_state) {
! 432: case LKMS_LOADED:
! 433: break;
! 434: case LKMS_LOADING:
! 435: case LKMS_LOADING_SYMS:
! 436: if ((curp->size - curp->offset) > 0)
! 437: /* The remainder must be bss, so we clear it */
! 438: bzero((caddr_t)curp->area + curp->offset,
! 439: curp->size - curp->offset);
! 440: break;
! 441: default:
! 442: return (ENXIO);
! 443: }
! 444:
! 445: curp->entry = (int (*)(struct lkm_table *, int, int))
! 446: (*((long *) (data)));
! 447:
! 448: #ifdef LKM_DEBUG
! 449: printf("LKM: call entrypoint %x\n", curp->entry);
! 450: #endif /* LKM_DEBUG */
! 451:
! 452: /* call entry(load)... (assigns "private" portion) */
! 453: error = (*(curp->entry))(curp, LKM_E_LOAD, curp->ver);
! 454: if (error) {
! 455: /*
! 456: * Module may refuse loading or may have a
! 457: * version mismatch...
! 458: */
! 459: lkm_state = LKMS_UNLOADING; /* for lkmunreserve */
! 460: lkmunreserve(); /* free memory */
! 461: lkmfree(curp); /* free slot */
! 462: break;
! 463: }
! 464:
! 465: #ifdef LKM_DEBUG
! 466: printf("LKM: LMREADY, id=%d, dev=%d\n", curp->id,
! 467: curp->private.lkm_any->lkm_offset);
! 468: #endif /* LKM_DEBUG */
! 469:
! 470: #ifdef DDB
! 471: if (curp->syms && curp->sym_offset >= curp->sym_size) {
! 472: curp->sym_id = db_add_symbol_table(curp->syms,
! 473: curp->syms + curp->sym_symsize,
! 474: curp->private.lkm_any->lkm_name,
! 475: curp->syms);
! 476: printf("DDB symbols added: %ld bytes\n",
! 477: curp->sym_symsize);
! 478: }
! 479: #endif /* DDB */
! 480:
! 481: curp->refcnt++;
! 482: lkm_state = LKMS_IDLE;
! 483: break;
! 484:
! 485: case LMUNLOAD: {
! 486: struct lmc_unload *unloadp = (struct lmc_unload *)data;
! 487:
! 488: curp = lkmlookup(unloadp->id, unloadp->name, &error);
! 489: if (curp == NULL)
! 490: break;
! 491:
! 492: /* call entry(unload) */
! 493: if ((*(curp->entry))(curp, LKM_E_UNLOAD, curp->ver)) {
! 494: error = EBUSY;
! 495: break;
! 496: }
! 497:
! 498: lkm_state = LKMS_UNLOADING; /* non-idle for lkmunreserve */
! 499: lkmunreserve(); /* free memory */
! 500: lkmfree(curp); /* free slot */
! 501: break;
! 502: }
! 503:
! 504: case LMSTAT: {
! 505: struct lmc_stat *statp = (struct lmc_stat *)data;
! 506:
! 507: if ((curp = lkmlookup(statp->id, statp->name, &error)) == NULL)
! 508: break;
! 509:
! 510: if ((error = (*curp->entry)(curp, LKM_E_STAT, curp->ver)))
! 511: break;
! 512:
! 513: /*
! 514: * Copy out stat information for this module...
! 515: */
! 516: statp->id = curp->id;
! 517: statp->offset = curp->private.lkm_any->lkm_offset;
! 518: statp->type = curp->private.lkm_any->lkm_type;
! 519: statp->area = curp->area;
! 520: statp->size = curp->size / PAGE_SIZE;
! 521: statp->private = (unsigned long)curp->private.lkm_any;
! 522: statp->ver = curp->private.lkm_any->lkm_ver;
! 523: copyoutstr(curp->private.lkm_any->lkm_name,
! 524: statp->name, MAXLKMNAME, NULL);
! 525:
! 526: break;
! 527: }
! 528:
! 529: default:
! 530: error = ENODEV;
! 531: break;
! 532: }
! 533:
! 534: return (error);
! 535: }
! 536:
! 537: /*
! 538: * Acts like "nosys" but can be identified in sysent for dynamic call
! 539: * number assignment for a limited number of calls.
! 540: *
! 541: * Place holder for system call slots reserved for loadable modules.
! 542: */
! 543: int
! 544: sys_lkmnosys(struct proc *p, void *v, register_t *retval)
! 545: {
! 546:
! 547: return (sys_nosys(p, v, retval));
! 548: }
! 549:
! 550: /*
! 551: * Acts like "enodev", but can be identified in cdevsw and bdevsw for
! 552: * dynamic driver major number assignment for a limited number of
! 553: * drivers.
! 554: *
! 555: * Place holder for device switch slots reserved for loadable modules.
! 556: */
! 557: int
! 558: lkmenodev(void)
! 559: {
! 560:
! 561: return (enodev());
! 562: }
! 563:
! 564: /*
! 565: * A placeholder function for load/unload/stat calls; simply returns zero.
! 566: * Used where people don't want to specify a special function.
! 567: */
! 568: int
! 569: lkm_nofunc(struct lkm_table *lkmtp, int cmd)
! 570: {
! 571:
! 572: return (0);
! 573: }
! 574:
! 575: int
! 576: lkmexists(struct lkm_table *lkmtp)
! 577: {
! 578: struct lkm_table *p;
! 579:
! 580: TAILQ_FOREACH(p, &lkmods, list) {
! 581: if (!strcmp(lkmtp->private.lkm_any->lkm_name,
! 582: p->private.lkm_any->lkm_name) && p->refcnt)
! 583: return (1);
! 584: }
! 585: return (0);
! 586: }
! 587:
! 588: /*
! 589: * For the loadable system call described by the structure pointed to
! 590: * by lkmtp, load/unload/stat it depending on the cmd requested.
! 591: */
! 592: static int
! 593: _lkm_syscall(struct lkm_table *lkmtp, int cmd)
! 594: {
! 595: struct lkm_syscall *args = lkmtp->private.lkm_syscall;
! 596: int i;
! 597: int error = 0;
! 598:
! 599: switch (cmd) {
! 600: case LKM_E_LOAD:
! 601: /* don't load twice! */
! 602: if (lkmexists(lkmtp))
! 603: return (EEXIST);
! 604:
! 605: if ((i = args->lkm_offset) == -1) { /* auto */
! 606: /*
! 607: * Search the table looking for a slot...
! 608: */
! 609: for (i = 0; i < SYS_MAXSYSCALL; i++)
! 610: if (sysent[i].sy_call == sys_lkmnosys)
! 611: break; /* found it! */
! 612: /* out of allocable slots? */
! 613: if (i == SYS_MAXSYSCALL) {
! 614: error = ENFILE;
! 615: break;
! 616: }
! 617: } else { /* assign */
! 618: if (i < 0 || i >= SYS_MAXSYSCALL) {
! 619: error = EINVAL;
! 620: break;
! 621: }
! 622: }
! 623:
! 624: /* save old */
! 625: bcopy(&sysent[i], &args->lkm_oldent, sizeof(struct sysent));
! 626:
! 627: /* replace with new */
! 628: bcopy(args->lkm_sysent, &sysent[i], sizeof(struct sysent));
! 629:
! 630: /* done! */
! 631: args->lkm_offset = i; /* slot in sysent[] */
! 632:
! 633: break;
! 634:
! 635: case LKM_E_UNLOAD:
! 636: /* current slot... */
! 637: i = args->lkm_offset;
! 638:
! 639: /* replace current slot contents with old contents */
! 640: bcopy(&args->lkm_oldent, &sysent[i], sizeof(struct sysent));
! 641:
! 642: break;
! 643:
! 644: case LKM_E_STAT: /* no special handling... */
! 645: break;
! 646: }
! 647:
! 648: return (error);
! 649: }
! 650:
! 651: /*
! 652: * For the loadable virtual file system described by the structure pointed
! 653: * to by lkmtp, load/unload/stat it depending on the cmd requested.
! 654: */
! 655: static int
! 656: _lkm_vfs(struct lkm_table *lkmtp, int cmd)
! 657: {
! 658: int error = 0;
! 659: struct lkm_vfs *args = lkmtp->private.lkm_vfs;
! 660:
! 661: switch (cmd) {
! 662: case LKM_E_LOAD:
! 663: /* don't load twice! */
! 664: if (lkmexists(lkmtp))
! 665: return (EEXIST);
! 666: error = vfs_register(args->lkm_vfsconf);
! 667: break;
! 668:
! 669: case LKM_E_UNLOAD:
! 670: error = vfs_unregister(args->lkm_vfsconf);
! 671: break;
! 672:
! 673: case LKM_E_STAT: /* no special handling... */
! 674: break;
! 675: }
! 676:
! 677: return (error);
! 678: }
! 679:
! 680: /*
! 681: * For the loadable device driver described by the structure pointed to
! 682: * by lkmtp, load/unload/stat it depending on the cmd requested.
! 683: */
! 684: static int
! 685: _lkm_dev(struct lkm_table *lkmtp, int cmd)
! 686: {
! 687: struct lkm_dev *args = lkmtp->private.lkm_dev;
! 688: int i;
! 689: int error = 0;
! 690:
! 691: switch (cmd) {
! 692: case LKM_E_LOAD:
! 693: /* don't load twice! */
! 694: if (lkmexists(lkmtp))
! 695: return (EEXIST);
! 696:
! 697: switch (args->lkm_devtype) {
! 698: case LM_DT_BLOCK:
! 699: if ((i = args->lkm_offset) == -1) { /* auto */
! 700: /*
! 701: * Search the table looking for a slot...
! 702: */
! 703: for (i = 0; i < nblkdev; i++)
! 704: if (bdevsw[i].d_open ==
! 705: (dev_type_open((*))) lkmenodev)
! 706: break; /* found it! */
! 707: /* out of allocable slots? */
! 708: if (i == nblkdev) {
! 709: error = ENFILE;
! 710: break;
! 711: }
! 712: } else { /* assign */
! 713: if (i < 0 || i >= nblkdev) {
! 714: error = EINVAL;
! 715: break;
! 716: }
! 717: }
! 718:
! 719: /* save old */
! 720: bcopy(&bdevsw[i], &args->lkm_olddev.bdev,
! 721: sizeof(struct bdevsw));
! 722:
! 723: /* replace with new */
! 724: bcopy(args->lkm_dev.bdev, &bdevsw[i],
! 725: sizeof(struct bdevsw));
! 726:
! 727: /* done! */
! 728: args->lkm_offset = i; /* slot in bdevsw[] */
! 729: break;
! 730:
! 731: case LM_DT_CHAR:
! 732: if ((i = args->lkm_offset) == -1) { /* auto */
! 733: /*
! 734: * Search the table looking for a slot...
! 735: */
! 736: for (i = 0; i < nchrdev; i++)
! 737: if (cdevsw[i].d_open ==
! 738: (dev_type_open((*))) lkmenodev)
! 739: break; /* found it! */
! 740: /* out of allocable slots? */
! 741: if (i == nchrdev) {
! 742: error = ENFILE;
! 743: break;
! 744: }
! 745: } else { /* assign */
! 746: if (i < 0 || i >= nchrdev) {
! 747: error = EINVAL;
! 748: break;
! 749: }
! 750: }
! 751:
! 752: /* save old */
! 753: bcopy(&cdevsw[i], &args->lkm_olddev.cdev,
! 754: sizeof(struct cdevsw));
! 755:
! 756: /* replace with new */
! 757: bcopy(args->lkm_dev.cdev, &cdevsw[i],
! 758: sizeof(struct cdevsw));
! 759:
! 760: /* done! */
! 761: args->lkm_offset = i; /* slot in cdevsw[] */
! 762:
! 763: break;
! 764:
! 765: default:
! 766: error = ENODEV;
! 767: break;
! 768: }
! 769: break;
! 770:
! 771: case LKM_E_UNLOAD:
! 772: /* current slot... */
! 773: i = args->lkm_offset;
! 774:
! 775: switch (args->lkm_devtype) {
! 776: case LM_DT_BLOCK:
! 777: /* replace current slot contents with old contents */
! 778: bcopy(&args->lkm_olddev.bdev, &bdevsw[i],
! 779: sizeof(struct bdevsw));
! 780: break;
! 781:
! 782: case LM_DT_CHAR:
! 783: /* replace current slot contents with old contents */
! 784: bcopy(&args->lkm_olddev.cdev, &cdevsw[i],
! 785: sizeof(struct cdevsw));
! 786: break;
! 787:
! 788: default:
! 789: error = ENODEV;
! 790: break;
! 791: }
! 792: break;
! 793:
! 794: case LKM_E_STAT: /* no special handling... */
! 795: break;
! 796: }
! 797:
! 798: return (error);
! 799: }
! 800:
! 801: /*
! 802: * For the loadable execution class described by the structure pointed to
! 803: * by lkmtp, load/unload/stat it depending on the cmd requested.
! 804: */
! 805: static int
! 806: _lkm_exec(struct lkm_table *lkmtp, int cmd)
! 807: {
! 808: struct lkm_exec *args = lkmtp->private.lkm_exec;
! 809: int i;
! 810: int error = 0;
! 811:
! 812: switch (cmd) {
! 813: case LKM_E_LOAD:
! 814: /* don't load twice! */
! 815: if (lkmexists(lkmtp))
! 816: return (EEXIST);
! 817:
! 818: if ((i = args->lkm_offset) == -1) { /* auto */
! 819: /*
! 820: * Search the table looking for a slot...
! 821: */
! 822: for (i = 0; i < nexecs; i++)
! 823: if (execsw[i].es_check == NULL)
! 824: break; /* found it! */
! 825: /* out of allocable slots? */
! 826: if (i == nexecs) {
! 827: error = ENFILE;
! 828: break;
! 829: }
! 830: } else { /* assign */
! 831: if (i < 0 || i >= nexecs) {
! 832: error = EINVAL;
! 833: break;
! 834: }
! 835: }
! 836:
! 837: /* save old */
! 838: bcopy(&execsw[i], &args->lkm_oldexec, sizeof(struct execsw));
! 839:
! 840: /* replace with new */
! 841: bcopy(args->lkm_exec, &execsw[i], sizeof(struct execsw));
! 842:
! 843: /* need to recompute max header size */
! 844: init_exec();
! 845:
! 846: /* done! */
! 847: args->lkm_offset = i; /* slot in execsw[] */
! 848:
! 849: break;
! 850:
! 851: case LKM_E_UNLOAD:
! 852: /* current slot... */
! 853: i = args->lkm_offset;
! 854:
! 855: /* replace current slot contents with old contents */
! 856: bcopy(&args->lkm_oldexec, &execsw[i], sizeof(struct execsw));
! 857:
! 858: /* need to recompute max header size */
! 859: init_exec();
! 860:
! 861: break;
! 862:
! 863: case LKM_E_STAT: /* no special handling... */
! 864: break;
! 865: }
! 866:
! 867: return (error);
! 868: }
! 869:
! 870: /*
! 871: * This code handles the per-module type "wiring-in" of loadable modules
! 872: * into existing kernel tables. For "LM_MISC" modules, wiring and unwiring
! 873: * is assumed to be done in their entry routines internal to the module
! 874: * itself.
! 875: */
! 876: int
! 877: lkmdispatch(struct lkm_table *lkmtp, int cmd)
! 878: {
! 879: int error = 0;
! 880:
! 881: #ifdef LKM_DEBUG
! 882: printf("lkmdispatch: %x %d\n", lkmtp, cmd);
! 883: #endif /* LKM_DEBUG */
! 884:
! 885: switch (lkmtp->private.lkm_any->lkm_type) {
! 886: case LM_SYSCALL:
! 887: error = _lkm_syscall(lkmtp, cmd);
! 888: break;
! 889:
! 890: case LM_VFS:
! 891: error = _lkm_vfs(lkmtp, cmd);
! 892: break;
! 893:
! 894: case LM_DEV:
! 895: error = _lkm_dev(lkmtp, cmd);
! 896: break;
! 897:
! 898: case LM_EXEC:
! 899: error = _lkm_exec(lkmtp, cmd);
! 900: break;
! 901:
! 902: case LM_MISC: /* ignore content -- no "misc-specific" procedure */
! 903: break;
! 904:
! 905: default:
! 906: error = ENXIO; /* unknown type */
! 907: break;
! 908: }
! 909:
! 910: return (error);
! 911: }
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