1 /*- 2 * Copyright (c) 2002 Poul-Henning Kamp 3 * Copyright (c) 2002 Networks Associates Technology, Inc. 4 * All rights reserved. 5 * 6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 7 * and NAI Labs, the Security Research Division of Network Associates, Inc. 8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 9 * DARPA CHATS research program. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The names of the authors may not be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/malloc.h> 42 #include <sys/kernel.h> 43 #include <sys/conf.h> 44 #include <sys/bio.h> 45 #include <sys/lock.h> 46 #include <sys/mutex.h> 47 #include <sys/proc.h> 48 #include <sys/errno.h> 49 #include <sys/time.h> 50 #include <sys/disk.h> 51 #include <sys/fcntl.h> 52 #include <sys/limits.h> 53 #include <geom/geom.h> 54 #include <geom/geom_int.h> 55 56 static d_open_t g_dev_open; 57 static d_close_t g_dev_close; 58 static d_strategy_t g_dev_strategy; 59 static d_ioctl_t g_dev_ioctl; 60 61 static struct cdevsw g_dev_cdevsw = { 62 .d_version = D_VERSION, 63 .d_open = g_dev_open, 64 .d_close = g_dev_close, 65 .d_read = physread, 66 .d_write = physwrite, 67 .d_ioctl = g_dev_ioctl, 68 .d_strategy = g_dev_strategy, 69 .d_name = "g_dev", 70 .d_flags = D_DISK | D_TRACKCLOSE, 71 }; 72 73 static g_taste_t g_dev_taste; 74 static g_orphan_t g_dev_orphan; 75 static g_init_t g_dev_init; 76 77 static struct g_class g_dev_class = { 78 .name = "DEV", 79 .version = G_VERSION, 80 .taste = g_dev_taste, 81 .orphan = g_dev_orphan, 82 .init = g_dev_init, 83 }; 84 85 static struct unrhdr *unithdr; /* Locked by topology */ 86 87 static void 88 g_dev_init(struct g_class *mp) 89 { 90 91 unithdr = new_unrhdr(0, minor2unit(MAXMINOR), NULL); 92 } 93 94 void 95 g_dev_print(void) 96 { 97 struct g_geom *gp; 98 char const *p = ""; 99 100 LIST_FOREACH(gp, &g_dev_class.geom, geom) { 101 printf("%s%s", p, gp->name); 102 p = " "; 103 } 104 printf("\n"); 105 } 106 107 struct g_provider * 108 g_dev_getprovider(struct cdev *dev) 109 { 110 struct g_consumer *cp; 111 112 g_topology_assert(); 113 if (dev == NULL) 114 return (NULL); 115 if (dev->si_devsw != &g_dev_cdevsw) 116 return (NULL); 117 cp = dev->si_drv2; 118 return (cp->provider); 119 } 120 121 122 static struct g_geom * 123 g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused) 124 { 125 struct g_geom *gp; 126 struct g_consumer *cp; 127 int error; 128 struct cdev *dev; 129 u_int unit; 130 131 g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name); 132 g_topology_assert(); 133 LIST_FOREACH(cp, &pp->consumers, consumers) 134 if (cp->geom->class == mp) 135 return (NULL); 136 gp = g_new_geomf(mp, pp->name); 137 cp = g_new_consumer(gp); 138 error = g_attach(cp, pp); 139 KASSERT(error == 0, 140 ("g_dev_taste(%s) failed to g_attach, err=%d", pp->name, error)); 141 unit = alloc_unr(unithdr); 142 dev = make_dev(&g_dev_cdevsw, unit2minor(unit), 143 UID_ROOT, GID_OPERATOR, 0640, gp->name); 144 if (pp->flags & G_PF_CANDELETE) 145 dev->si_flags |= SI_CANDELETE; 146 dev->si_iosize_max = MAXPHYS; 147 gp->softc = dev; 148 dev->si_drv1 = gp; 149 dev->si_drv2 = cp; 150 return (gp); 151 } 152 153 static int 154 g_dev_open(struct cdev *dev, int flags, int fmt, struct thread *td) 155 { 156 struct g_geom *gp; 157 struct g_consumer *cp; 158 int error, r, w, e; 159 160 gp = dev->si_drv1; 161 cp = dev->si_drv2; 162 if (gp == NULL || cp == NULL || gp->softc != dev) 163 return(ENXIO); /* g_dev_taste() not done yet */ 164 165 g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)", 166 gp->name, flags, fmt, td); 167 168 r = flags & FREAD ? 1 : 0; 169 w = flags & FWRITE ? 1 : 0; 170 #ifdef notyet 171 e = flags & O_EXCL ? 1 : 0; 172 #else 173 e = 0; 174 #endif 175 if (w) { 176 /* 177 * When running in very secure mode, do not allow 178 * opens for writing of any disks. 179 */ 180 error = securelevel_ge(td->td_ucred, 2); 181 if (error) 182 return (error); 183 } 184 g_topology_lock(); 185 if (dev->si_devsw == NULL) 186 error = ENXIO; /* We were orphaned */ 187 else 188 error = g_access(cp, r, w, e); 189 g_topology_unlock(); 190 return(error); 191 } 192 193 static int 194 g_dev_close(struct cdev *dev, int flags, int fmt, struct thread *td) 195 { 196 struct g_geom *gp; 197 struct g_consumer *cp; 198 int error, r, w, e, i; 199 200 gp = dev->si_drv1; 201 cp = dev->si_drv2; 202 if (gp == NULL || cp == NULL) 203 return(ENXIO); 204 g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)", 205 gp->name, flags, fmt, td); 206 r = flags & FREAD ? -1 : 0; 207 w = flags & FWRITE ? -1 : 0; 208 #ifdef notyet 209 e = flags & O_EXCL ? -1 : 0; 210 #else 211 e = 0; 212 #endif 213 g_topology_lock(); 214 if (dev->si_devsw == NULL) 215 error = ENXIO; /* We were orphaned */ 216 else 217 error = g_access(cp, r, w, e); 218 for (i = 0; i < 10 * hz;) { 219 if (cp->acr != 0 || cp->acw != 0) 220 break; 221 if (cp->nstart == cp->nend) 222 break; 223 pause("gdevwclose", hz / 10); 224 i += hz / 10; 225 } 226 if (cp->acr == 0 && cp->acw == 0 && cp->nstart != cp->nend) { 227 printf("WARNING: Final close of geom_dev(%s) %s %s\n", 228 gp->name, 229 "still has outstanding I/O after 10 seconds.", 230 "Completing close anyway, panic may happen later."); 231 } 232 g_topology_unlock(); 233 return (error); 234 } 235 236 /* 237 * XXX: Until we have unmessed the ioctl situation, there is a race against 238 * XXX: a concurrent orphanization. We cannot close it by holding topology 239 * XXX: since that would prevent us from doing our job, and stalling events 240 * XXX: will break (actually: stall) the BSD disklabel hacks. 241 */ 242 static int 243 g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 244 { 245 struct g_geom *gp; 246 struct g_consumer *cp; 247 struct g_kerneldump kd; 248 off_t offset, length; 249 int i, error; 250 u_int u; 251 252 gp = dev->si_drv1; 253 cp = dev->si_drv2; 254 255 error = 0; 256 KASSERT(cp->acr || cp->acw, 257 ("Consumer with zero access count in g_dev_ioctl")); 258 259 i = IOCPARM_LEN(cmd); 260 switch (cmd) { 261 case DIOCGSECTORSIZE: 262 *(u_int *)data = cp->provider->sectorsize; 263 if (*(u_int *)data == 0) 264 error = ENOENT; 265 break; 266 case DIOCGMEDIASIZE: 267 *(off_t *)data = cp->provider->mediasize; 268 if (*(off_t *)data == 0) 269 error = ENOENT; 270 break; 271 case DIOCGFWSECTORS: 272 error = g_io_getattr("GEOM::fwsectors", cp, &i, data); 273 if (error == 0 && *(u_int *)data == 0) 274 error = ENOENT; 275 break; 276 case DIOCGFWHEADS: 277 error = g_io_getattr("GEOM::fwheads", cp, &i, data); 278 if (error == 0 && *(u_int *)data == 0) 279 error = ENOENT; 280 break; 281 case DIOCGFRONTSTUFF: 282 error = g_io_getattr("GEOM::frontstuff", cp, &i, data); 283 break; 284 case DIOCSKERNELDUMP: 285 u = *((u_int *)data); 286 if (!u) { 287 set_dumper(NULL); 288 error = 0; 289 break; 290 } 291 kd.offset = 0; 292 kd.length = OFF_MAX; 293 i = sizeof kd; 294 error = g_io_getattr("GEOM::kerneldump", cp, &i, &kd); 295 if (!error) 296 dev->si_flags |= SI_DUMPDEV; 297 break; 298 case DIOCGFLUSH: 299 error = g_io_flush(cp); 300 break; 301 case DIOCGDELETE: 302 offset = ((off_t *)data)[0]; 303 length = ((off_t *)data)[1]; 304 if ((offset % cp->provider->sectorsize) != 0 || 305 (length % cp->provider->sectorsize) != 0 || 306 length <= 0 || length > MAXPHYS) { 307 printf("%s: offset=%jd length=%jd\n", __func__, offset, 308 length); 309 error = EINVAL; 310 break; 311 } 312 error = g_delete_data(cp, offset, length); 313 break; 314 case DIOCGIDENT: 315 error = g_io_getattr("GEOM::ident", cp, &i, data); 316 break; 317 318 default: 319 if (cp->provider->geom->ioctl != NULL) { 320 error = cp->provider->geom->ioctl(cp->provider, cmd, data, fflag, td); 321 } else { 322 error = ENOIOCTL; 323 } 324 } 325 326 return (error); 327 } 328 329 static void 330 g_dev_done(struct bio *bp2) 331 { 332 struct bio *bp; 333 334 bp = bp2->bio_parent; 335 bp->bio_error = bp2->bio_error; 336 if (bp->bio_error != 0) { 337 g_trace(G_T_BIO, "g_dev_done(%p) had error %d", 338 bp2, bp->bio_error); 339 bp->bio_flags |= BIO_ERROR; 340 } else { 341 g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd", 342 bp2, bp, bp->bio_resid, (intmax_t)bp2->bio_completed); 343 } 344 bp->bio_resid = bp->bio_length - bp2->bio_completed; 345 bp->bio_completed = bp2->bio_completed; 346 g_destroy_bio(bp2); 347 biodone(bp); 348 } 349 350 static void 351 g_dev_strategy(struct bio *bp) 352 { 353 struct g_consumer *cp; 354 struct bio *bp2; 355 struct cdev *dev; 356 357 KASSERT(bp->bio_cmd == BIO_READ || 358 bp->bio_cmd == BIO_WRITE || 359 bp->bio_cmd == BIO_DELETE, 360 ("Wrong bio_cmd bio=%p cmd=%d", bp, bp->bio_cmd)); 361 dev = bp->bio_dev; 362 cp = dev->si_drv2; 363 KASSERT(cp->acr || cp->acw, 364 ("Consumer with zero access count in g_dev_strategy")); 365 366 if ((bp->bio_offset % cp->provider->sectorsize) != 0 || 367 (bp->bio_bcount % cp->provider->sectorsize) != 0) { 368 bp->bio_resid = bp->bio_bcount; 369 biofinish(bp, NULL, EINVAL); 370 return; 371 } 372 373 for (;;) { 374 /* 375 * XXX: This is not an ideal solution, but I belive it to 376 * XXX: deadlock safe, all things considered. 377 */ 378 bp2 = g_clone_bio(bp); 379 if (bp2 != NULL) 380 break; 381 pause("gdstrat", hz / 10); 382 } 383 KASSERT(bp2 != NULL, ("XXX: ENOMEM in a bad place")); 384 bp2->bio_done = g_dev_done; 385 g_trace(G_T_BIO, 386 "g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d", 387 bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length, 388 bp2->bio_data, bp2->bio_cmd); 389 g_io_request(bp2, cp); 390 KASSERT(cp->acr || cp->acw, 391 ("g_dev_strategy raced with g_dev_close and lost")); 392 393 } 394 395 /* 396 * g_dev_orphan() 397 * 398 * Called from below when the provider orphaned us. 399 * - Clear any dump settings. 400 * - Destroy the struct cdev *to prevent any more request from coming in. The 401 * provider is already marked with an error, so anything which comes in 402 * in the interrim will be returned immediately. 403 * - Wait for any outstanding I/O to finish. 404 * - Set our access counts to zero, whatever they were. 405 * - Detach and self-destruct. 406 */ 407 408 static void 409 g_dev_orphan(struct g_consumer *cp) 410 { 411 struct g_geom *gp; 412 struct cdev *dev; 413 u_int unit; 414 415 g_topology_assert(); 416 gp = cp->geom; 417 dev = gp->softc; 418 g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, gp->name); 419 420 /* Reset any dump-area set on this device */ 421 if (dev->si_flags & SI_DUMPDEV) 422 set_dumper(NULL); 423 424 /* Destroy the struct cdev *so we get no more requests */ 425 unit = dev2unit(dev); 426 destroy_dev(dev); 427 free_unr(unithdr, unit); 428 429 /* Wait for the cows to come home */ 430 while (cp->nstart != cp->nend) 431 pause("gdevorphan", hz / 10); 432 433 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 434 g_access(cp, -cp->acr, -cp->acw, -cp->ace); 435 436 g_detach(cp); 437 g_destroy_consumer(cp); 438 g_destroy_geom(gp); 439 } 440 441 DECLARE_GEOM_CLASS(g_dev_class, g_dev); 442