geom_dev.c revision 105941
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 * $FreeBSD: head/sys/geom/geom_dev.c 105941 2002-10-25 17:00:15Z phk $ 36 */ 37 38#include <sys/param.h> 39#include <sys/stdint.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/errno.h> 48#include <sys/time.h> 49#include <sys/disk.h> 50#include <sys/fcntl.h> 51#include <geom/geom.h> 52#include <geom/geom_int.h> 53#include <machine/limits.h> 54 55#define CDEV_MAJOR 4 56 57static d_open_t g_dev_open; 58static d_close_t g_dev_close; 59static d_strategy_t g_dev_strategy; 60static d_ioctl_t g_dev_ioctl; 61static d_psize_t g_dev_psize; 62 63static struct cdevsw g_dev_cdevsw = { 64 /* open */ g_dev_open, 65 /* close */ g_dev_close, 66 /* read */ physread, 67 /* write */ physwrite, 68 /* ioctl */ g_dev_ioctl, 69 /* poll */ nopoll, 70 /* mmap */ nommap, 71 /* strategy */ g_dev_strategy, 72 /* name */ "g_dev", 73 /* maj */ CDEV_MAJOR, 74 /* dump */ nodump, 75 /* psize */ g_dev_psize, 76 /* flags */ D_DISK | D_CANFREE | D_TRACKCLOSE, 77 /* kqfilter */ nokqfilter 78}; 79 80static g_taste_t g_dev_taste; 81static g_orphan_t g_dev_orphan; 82 83static struct g_class g_dev_class = { 84 "DEV", 85 g_dev_taste, 86 NULL, 87 G_CLASS_INITIALIZER 88}; 89 90static void 91g_dev_clone(void *arg __unused, char *name, int namelen __unused, dev_t *dev) 92{ 93 struct g_geom *gp; 94 95 if (*dev != NODEV) 96 return; 97 98 g_waitidle(); 99 100 /* XXX: can I drop Giant here ??? */ 101 /* g_topology_lock(); */ 102 LIST_FOREACH(gp, &g_dev_class.geom, geom) { 103 if (strcmp(gp->name, name)) 104 continue; 105 *dev = gp->softc; 106 g_trace(G_T_TOPOLOGY, "g_dev_clone(%s) = %p", name, *dev); 107 return; 108 } 109 /* g_topology_unlock(); */ 110 return; 111} 112 113static void 114g_dev_register_cloner(void *foo __unused) 115{ 116 static int once; 117 118 /* XXX: why would this happen more than once ?? */ 119 if (!once) { 120 EVENTHANDLER_REGISTER(dev_clone, g_dev_clone, 0, 1000); 121 once++; 122 } 123} 124 125SYSINIT(geomdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,g_dev_register_cloner,NULL); 126 127static struct g_geom * 128g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused) 129{ 130 struct g_geom *gp; 131 struct g_consumer *cp; 132 static int unit; 133 int error; 134 dev_t dev; 135 136 g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name); 137 g_topology_assert(); 138 LIST_FOREACH(cp, &pp->consumers, consumers) 139 if (cp->geom->class == mp) 140 return (NULL); 141 gp = g_new_geomf(mp, pp->name); 142 gp->orphan = g_dev_orphan; 143 cp = g_new_consumer(gp); 144 error = g_attach(cp, pp); 145 KASSERT(error == 0, 146 ("g_dev_taste(%s) failed to g_attach, err=%d", pp->name, error)); 147 /* 148 * XXX: I'm not 100% sure we can call make_dev(9) without Giant 149 * yet. Once we can, we don't need to drop topology here either. 150 */ 151 g_topology_unlock(); 152 mtx_lock(&Giant); 153 dev = make_dev(&g_dev_cdevsw, unit2minor(unit++), 154 UID_ROOT, GID_OPERATOR, 0640, gp->name); 155 mtx_unlock(&Giant); 156 g_topology_lock(); 157 158 gp->softc = dev; 159 dev->si_drv1 = gp; 160 dev->si_drv2 = cp; 161 return (gp); 162} 163 164static int 165g_dev_open(dev_t dev, int flags, int fmt, struct thread *td) 166{ 167 struct g_geom *gp; 168 struct g_consumer *cp; 169 int error, r, w, e; 170 171 gp = dev->si_drv1; 172 cp = dev->si_drv2; 173 if (gp == NULL || cp == NULL) 174 return(ENXIO); 175 g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)", 176 gp->name, flags, fmt, td); 177 DROP_GIANT(); 178 g_topology_lock(); 179 g_silence(); 180 r = flags & FREAD ? 1 : 0; 181 w = flags & FWRITE ? 1 : 0; 182#ifdef notyet 183 e = flags & O_EXCL ? 1 : 0; 184#else 185 e = 0; 186#endif 187 error = g_access_rel(cp, r, w, e); 188 g_topology_unlock(); 189 PICKUP_GIANT(); 190 g_waitidle(); 191 return(error); 192} 193 194static int 195g_dev_close(dev_t dev, int flags, int fmt, struct thread *td) 196{ 197 struct g_geom *gp; 198 struct g_consumer *cp; 199 int error, r, w, e; 200 201 gp = dev->si_drv1; 202 cp = dev->si_drv2; 203 if (gp == NULL || cp == NULL) 204 return(ENXIO); 205 g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)", 206 gp->name, flags, fmt, td); 207 DROP_GIANT(); 208 g_topology_lock(); 209 g_silence(); 210 r = flags & FREAD ? -1 : 0; 211 w = flags & FWRITE ? -1 : 0; 212#ifdef notyet 213 e = flags & O_EXCL ? -1 : 0; 214#else 215 e = 0; 216#endif 217 error = g_access_rel(cp, r, w, e); 218 g_topology_unlock(); 219 PICKUP_GIANT(); 220 g_waitidle(); 221 return (error); 222} 223 224static int 225g_dev_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td) 226{ 227 struct g_geom *gp, *gp2; 228 struct g_consumer *cp; 229 struct g_provider *pp2; 230 struct g_kerneldump kd; 231 int i, error; 232 u_int u; 233 struct g_ioctl *gio; 234 235 gp = dev->si_drv1; 236 cp = dev->si_drv2; 237 pp2 = cp->provider; 238 gp2 = pp2->geom; 239 gio = NULL; 240 241 error = 0; 242 DROP_GIANT(); 243 244 i = IOCPARM_LEN(cmd); 245 switch (cmd) { 246 case DIOCGSECTORSIZE: 247 *(u_int *)data = cp->provider->sectorsize; 248 if (*(u_int *)data == 0) 249 error = ENOENT; 250 break; 251 case DIOCGMEDIASIZE: 252 *(off_t *)data = cp->provider->mediasize; 253 if (*(off_t *)data == 0) 254 error = ENOENT; 255 break; 256 case DIOCGFWSECTORS: 257 error = g_io_getattr("GEOM::fwsectors", cp, &i, data); 258 if (error == 0 && *(u_int *)data == 0) 259 error = ENOENT; 260 break; 261 case DIOCGFWHEADS: 262 error = g_io_getattr("GEOM::fwheads", cp, &i, data); 263 if (error == 0 && *(u_int *)data == 0) 264 error = ENOENT; 265 break; 266 case DIOCGFRONTSTUFF: 267 error = g_io_getattr("GEOM::frontstuff", cp, &i, data); 268 break; 269 case DIOCSKERNELDUMP: 270 u = *((u_int *)data); 271 if (!u) { 272 set_dumper(NULL); 273 error = 0; 274 break; 275 } 276 kd.offset = 0; 277 kd.length = OFF_MAX; 278 i = sizeof kd; 279 error = g_io_getattr("GEOM::kerneldump", cp, &i, &kd); 280 if (!error) 281 dev->si_flags |= SI_DUMPDEV; 282 break; 283 284 default: 285 gio = g_malloc(sizeof *gio, M_WAITOK | M_ZERO); 286 gio->cmd = cmd; 287 gio->data = data; 288 gio->fflag = fflag; 289 gio->td = td; 290 i = sizeof *gio; 291 if (cmd & IOC_IN) 292 error = g_io_setattr("GEOM::ioctl", cp, i, gio); 293 else 294 error = g_io_getattr("GEOM::ioctl", cp, &i, gio); 295 break; 296 } 297 298 PICKUP_GIANT(); 299 if (error == EDIRIOCTL) { 300 KASSERT(gio != NULL, ("NULL gio but EDIRIOCTL")); 301 KASSERT(gio->func != NULL, ("NULL function but EDIRIOCTL")); 302 error = (gio->func)(gio->dev, cmd, data, fflag, td); 303 } 304 if (gio != NULL) 305 g_free(gio); 306 g_waitidle(); 307 if (error == ENOIOCTL) { 308 if (g_debugflags & G_T_TOPOLOGY) { 309 i = IOCGROUP(cmd); 310 printf("IOCTL(0x%lx) \"%s\"", cmd, gp->name); 311 if (i > ' ' && i <= '~') 312 printf(" '%c'", (int)IOCGROUP(cmd)); 313 else 314 printf(" 0x%lx", IOCGROUP(cmd)); 315 printf("/%ld ", cmd & 0xff); 316 if (cmd & IOC_IN) 317 printf("I"); 318 if (cmd & IOC_OUT) 319 printf("O"); 320 printf("(%ld) = ENOIOCTL\n", IOCPARM_LEN(cmd)); 321 } 322 error = ENOTTY; 323 } 324 return (error); 325} 326 327static int 328g_dev_psize(dev_t dev) 329{ 330 struct g_consumer *cp; 331 off_t mediasize; 332 333 cp = dev->si_drv2; 334 335 mediasize = cp->provider->mediasize; 336 return (mediasize >> DEV_BSHIFT); 337} 338 339static void 340g_dev_done(struct bio *bp2) 341{ 342 struct bio *bp; 343 344 bp = bp2->bio_linkage; 345 bp->bio_error = bp2->bio_error; 346 if (bp->bio_error != 0) { 347 g_trace(G_T_BIO, "g_dev_done(%p) had error %d", 348 bp2, bp->bio_error); 349 bp->bio_flags |= BIO_ERROR; 350 } else { 351 g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd", 352 bp2, bp, bp->bio_resid, (intmax_t)bp2->bio_completed); 353 } 354 bp->bio_resid = bp->bio_bcount - bp2->bio_completed; 355 g_destroy_bio(bp2); 356 mtx_lock(&Giant); 357 biodone(bp); 358 mtx_unlock(&Giant); 359} 360 361static void 362g_dev_strategy(struct bio *bp) 363{ 364 struct g_geom *gp; 365 struct g_consumer *cp; 366 struct bio *bp2; 367 dev_t dev; 368 369 dev = bp->bio_dev; 370 gp = dev->si_drv1; 371 cp = dev->si_drv2; 372 bp2 = g_clone_bio(bp); 373 bp2->bio_offset = (off_t)bp->bio_blkno << DEV_BSHIFT; 374 bp2->bio_length = (off_t)bp->bio_bcount; 375 bp2->bio_done = g_dev_done; 376 g_trace(G_T_BIO, 377 "g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d", 378 bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length, 379 bp2->bio_data, bp2->bio_cmd); 380 g_io_request(bp2, cp); 381} 382 383/* 384 * g_dev_orphan() 385 * 386 * Called from below when the provider orphaned us. It is our responsibility 387 * to get the access counts back to zero, until we do so the stack below will 388 * not unravel. We must clear the kernel-dump settings, if this is the 389 * current dumpdev. We call destroy_dev(9) to send our dev_t the way of 390 * punched cards and if we have non-zero access counts, we call down with 391 * them negated before we detattch and selfdestruct. 392 */ 393 394static void 395g_dev_orphan(struct g_consumer *cp) 396{ 397 struct g_geom *gp; 398 dev_t dev; 399 400 gp = cp->geom; 401 g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, gp->name); 402 g_topology_assert(); 403 if (cp->biocount > 0) 404 return; 405 dev = gp->softc; 406 if (dev->si_flags & SI_DUMPDEV) 407 set_dumper(NULL); 408 /* XXX: we may need Giant for now */ 409 destroy_dev(dev); 410 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 411 g_access_rel(cp, -cp->acr, -cp->acw, -cp->ace); 412 g_detach(cp); 413 g_destroy_consumer(cp); 414 g_destroy_geom(gp); 415} 416 417DECLARE_GEOM_CLASS(g_dev_class, g_dev); 418