geom_slice.c revision 131046
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: head/sys/geom/geom_slice.c 131046 2004-06-24 10:50:20Z pjd $"); 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/kernel.h> 42#include <sys/malloc.h> 43#include <sys/bio.h> 44#include <sys/sysctl.h> 45#include <sys/proc.h> 46#include <sys/kthread.h> 47#include <sys/lock.h> 48#include <sys/mutex.h> 49#include <sys/errno.h> 50#include <sys/sbuf.h> 51#include <geom/geom.h> 52#include <geom/geom_slice.h> 53#include <machine/stdarg.h> 54 55static g_orphan_t g_slice_orphan; 56static g_access_t g_slice_access; 57static g_start_t g_slice_start; 58 59static struct g_slicer * 60g_slice_alloc(unsigned nslice, unsigned scsize) 61{ 62 struct g_slicer *gsp; 63 64 gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO); 65 if (scsize > 0) 66 gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO); 67 else 68 gsp->softc = NULL; 69 gsp->slices = g_malloc(nslice * sizeof(struct g_slice), 70 M_WAITOK | M_ZERO); 71 gsp->nslice = nslice; 72 return (gsp); 73} 74 75static void 76g_slice_free(struct g_slicer *gsp) 77{ 78 79 g_free(gsp->slices); 80 if (gsp->hotspot != NULL) 81 g_free(gsp->hotspot); 82 g_free(gsp->softc); 83 g_free(gsp); 84} 85 86static int 87g_slice_access(struct g_provider *pp, int dr, int dw, int de) 88{ 89 int error; 90 u_int u; 91 struct g_geom *gp; 92 struct g_consumer *cp; 93 struct g_provider *pp2; 94 struct g_slicer *gsp; 95 struct g_slice *gsl, *gsl2; 96 97 gp = pp->geom; 98 cp = LIST_FIRST(&gp->consumer); 99 KASSERT (cp != NULL, ("g_slice_access but no consumer")); 100 gsp = gp->softc; 101 gsl = &gsp->slices[pp->index]; 102 for (u = 0; u < gsp->nslice; u++) { 103 gsl2 = &gsp->slices[u]; 104 if (gsl2->length == 0) 105 continue; 106 if (u == pp->index) 107 continue; 108 if (gsl->offset + gsl->length <= gsl2->offset) 109 continue; 110 if (gsl2->offset + gsl2->length <= gsl->offset) 111 continue; 112 /* overlap */ 113 pp2 = gsl2->provider; 114 if ((pp->acw + dw) > 0 && pp2->ace > 0) 115 return (EPERM); 116 if ((pp->ace + de) > 0 && pp2->acw > 0) 117 return (EPERM); 118 } 119 /* On first open, grab an extra "exclusive" bit */ 120 if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) 121 de++; 122 /* ... and let go of it on last close */ 123 if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) 124 de--; 125 error = g_access(cp, dr, dw, de); 126 return (error); 127} 128 129/* 130 * XXX: It should be possible to specify here if we should finish all of the 131 * XXX: bio, or only the non-hot bits. This would get messy if there were 132 * XXX: two hot spots in the same bio, so for now we simply finish off the 133 * XXX: entire bio. Modifying hot data on the way to disk is frowned on 134 * XXX: so making that considerably harder is not a bad idea anyway. 135 */ 136void 137g_slice_finish_hot(struct bio *bp) 138{ 139 struct bio *bp2; 140 struct g_geom *gp; 141 struct g_consumer *cp; 142 struct g_slicer *gsp; 143 struct g_slice *gsl; 144 int idx; 145 146 KASSERT(bp->bio_to != NULL, 147 ("NULL bio_to in g_slice_finish_hot(%p)", bp)); 148 KASSERT(bp->bio_from != NULL, 149 ("NULL bio_from in g_slice_finish_hot(%p)", bp)); 150 gp = bp->bio_to->geom; 151 gsp = gp->softc; 152 cp = LIST_FIRST(&gp->consumer); 153 KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp)); 154 idx = bp->bio_to->index; 155 gsl = &gsp->slices[idx]; 156 157 bp2 = g_clone_bio(bp); 158 if (bp2 == NULL) { 159 g_io_deliver(bp, ENOMEM); 160 return; 161 } 162 if (bp2->bio_offset + bp2->bio_length > gsl->length) 163 bp2->bio_length = gsl->length - bp2->bio_offset; 164 bp2->bio_done = g_std_done; 165 bp2->bio_offset += gsl->offset; 166 g_io_request(bp2, cp); 167 return; 168} 169 170static void 171g_slice_start(struct bio *bp) 172{ 173 struct bio *bp2; 174 struct g_provider *pp; 175 struct g_geom *gp; 176 struct g_consumer *cp; 177 struct g_slicer *gsp; 178 struct g_slice *gsl; 179 struct g_slice_hot *ghp; 180 int idx, error; 181 u_int m_index; 182 off_t t; 183 184 pp = bp->bio_to; 185 gp = pp->geom; 186 gsp = gp->softc; 187 cp = LIST_FIRST(&gp->consumer); 188 idx = pp->index; 189 gsl = &gsp->slices[idx]; 190 switch(bp->bio_cmd) { 191 case BIO_READ: 192 case BIO_WRITE: 193 case BIO_DELETE: 194 if (bp->bio_offset > gsl->length) { 195 g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */ 196 return; 197 } 198 /* 199 * Check if we collide with any hot spaces, and call the 200 * method once if so. 201 */ 202 t = bp->bio_offset + gsl->offset; 203 for (m_index = 0; m_index < gsp->nhotspot; m_index++) { 204 ghp = &gsp->hotspot[m_index]; 205 if (t >= ghp->offset + ghp->length) 206 continue; 207 if (t + bp->bio_length <= ghp->offset) 208 continue; 209 switch(bp->bio_cmd) { 210 case BIO_READ: idx = ghp->ract; break; 211 case BIO_WRITE: idx = ghp->wact; break; 212 case BIO_DELETE: idx = ghp->dact; break; 213 } 214 switch(idx) { 215 case G_SLICE_HOT_ALLOW: 216 /* Fall out and continue normal processing */ 217 continue; 218 case G_SLICE_HOT_DENY: 219 g_io_deliver(bp, EROFS); 220 return; 221 case G_SLICE_HOT_START: 222 error = gsp->start(bp); 223 if (error && error != EJUSTRETURN) 224 g_io_deliver(bp, error); 225 return; 226 case G_SLICE_HOT_CALL: 227 error = g_post_event(gsp->hot, bp, M_NOWAIT, 228 gp, NULL); 229 if (error) 230 g_io_deliver(bp, error); 231 return; 232 } 233 break; 234 } 235 bp2 = g_clone_bio(bp); 236 if (bp2 == NULL) { 237 g_io_deliver(bp, ENOMEM); 238 return; 239 } 240 if (bp2->bio_offset + bp2->bio_length > gsl->length) 241 bp2->bio_length = gsl->length - bp2->bio_offset; 242 bp2->bio_done = g_std_done; 243 bp2->bio_offset += gsl->offset; 244 g_io_request(bp2, cp); 245 return; 246 case BIO_GETATTR: 247 /* Give the real method a chance to override */ 248 if (gsp->start != NULL && gsp->start(bp)) 249 return; 250 if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) { 251 struct g_kerneldump *gkd; 252 253 gkd = (struct g_kerneldump *)bp->bio_data; 254 gkd->offset += gsp->slices[idx].offset; 255 if (gkd->length > gsp->slices[idx].length) 256 gkd->length = gsp->slices[idx].length; 257 /* now, pass it on downwards... */ 258 } 259 bp2 = g_clone_bio(bp); 260 if (bp2 == NULL) { 261 g_io_deliver(bp, ENOMEM); 262 return; 263 } 264 bp2->bio_done = g_std_done; 265 g_io_request(bp2, cp); 266 break; 267 default: 268 g_io_deliver(bp, EOPNOTSUPP); 269 return; 270 } 271} 272 273void 274g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp) 275{ 276 struct g_slicer *gsp; 277 278 gsp = gp->softc; 279 if (indent == NULL) { 280 sbuf_printf(sb, " i %u", pp->index); 281 sbuf_printf(sb, " o %ju", 282 (uintmax_t)gsp->slices[pp->index].offset); 283 return; 284 } 285 if (pp != NULL) { 286 sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index); 287 sbuf_printf(sb, "%s<length>%ju</length>\n", 288 indent, (uintmax_t)gsp->slices[pp->index].length); 289 sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent, 290 (uintmax_t)gsp->slices[pp->index].length / 512); 291 sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent, 292 (uintmax_t)gsp->slices[pp->index].offset); 293 sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent, 294 (uintmax_t)gsp->slices[pp->index].offset / 512); 295 } 296} 297 298int 299g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...) 300{ 301 struct g_provider *pp, *pp2; 302 struct g_slicer *gsp; 303 struct g_slice *gsl; 304 va_list ap; 305 struct sbuf *sb; 306 int acc; 307 308 g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)", 309 gp->name, idx, how); 310 g_topology_assert(); 311 gsp = gp->softc; 312 if (idx >= gsp->nslice) 313 return(EINVAL); 314 gsl = &gsp->slices[idx]; 315 pp = gsl->provider; 316 if (pp != NULL) 317 acc = pp->acr + pp->acw + pp->ace; 318 else 319 acc = 0; 320 if (acc != 0 && how != G_SLICE_CONFIG_FORCE) { 321 if (length < gsl->length) 322 return(EBUSY); 323 if (offset != gsl->offset) 324 return(EBUSY); 325 } 326 /* XXX: check offset + length <= MEDIASIZE */ 327 if (how == G_SLICE_CONFIG_CHECK) 328 return (0); 329 gsl->length = length; 330 gsl->offset = offset; 331 gsl->sectorsize = sectorsize; 332 if (length == 0) { 333 if (pp == NULL) 334 return (0); 335 if (bootverbose) 336 printf("GEOM: Deconfigure %s\n", pp->name); 337 g_orphan_provider(pp, ENXIO); 338 gsl->provider = NULL; 339 gsp->nprovider--; 340 return (0); 341 } 342 if (pp != NULL) { 343 if (bootverbose) 344 printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n", 345 pp->name, (intmax_t)offset, (intmax_t)length, 346 (intmax_t)(offset + length - 1)); 347 pp->mediasize = gsl->length; 348 return (0); 349 } 350 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 351 va_start(ap, fmt); 352 sbuf_vprintf(sb, fmt, ap); 353 va_end(ap); 354 sbuf_finish(sb); 355 pp = g_new_providerf(gp, sbuf_data(sb)); 356 pp2 = LIST_FIRST(&gp->consumer)->provider; 357 pp->flags = pp2->flags & G_PF_CANDELETE; 358 if (pp2->stripesize > 0) { 359 pp->stripesize = pp2->stripesize; 360 pp->stripeoffset = (pp2->stripeoffset + offset) % pp->stripesize; 361 } 362 if (bootverbose) 363 printf("GEOM: Configure %s, start %jd length %jd end %jd\n", 364 pp->name, (intmax_t)offset, (intmax_t)length, 365 (intmax_t)(offset + length - 1)); 366 pp->index = idx; 367 pp->mediasize = gsl->length; 368 pp->sectorsize = gsl->sectorsize; 369 gsl->provider = pp; 370 gsp->nprovider++; 371 g_error_provider(pp, 0); 372 sbuf_delete(sb); 373 return(0); 374} 375 376/* 377 * Configure "hotspots". A hotspot is a piece of the parent device which 378 * this particular slicer cares about for some reason. Typically because 379 * it contains meta-data used to configure the slicer. 380 * A hotspot is identified by its index number. The offset and length are 381 * relative to the parent device, and the three "?act" fields specify 382 * what action to take on BIO_READ, BIO_DELETE and BIO_WRITE. 383 * 384 * XXX: There may be a race relative to g_slice_start() here, if an existing 385 * XXX: hotspot is changed wile I/O is happening. Should this become a problem 386 * XXX: we can protect the hotspot stuff with a mutex. 387 */ 388 389int 390g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length, int ract, int dact, int wact) 391{ 392 struct g_slicer *gsp; 393 struct g_slice_hot *gsl, *gsl2; 394 395 g_trace(G_T_TOPOLOGY, "g_slice_conf_hot(%s, idx: %d, off: %jd, len: %jd)", 396 gp->name, idx, (intmax_t)offset, (intmax_t)length); 397 g_topology_assert(); 398 gsp = gp->softc; 399 gsl = gsp->hotspot; 400 if(idx >= gsp->nhotspot) { 401 gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO); 402 if (gsp->hotspot != NULL) 403 bcopy(gsp->hotspot, gsl2, gsp->nhotspot * sizeof *gsl2); 404 gsp->hotspot = gsl2; 405 if (gsp->hotspot != NULL) 406 g_free(gsl); 407 gsl = gsl2; 408 gsp->nhotspot = idx + 1; 409 } 410 gsl[idx].offset = offset; 411 gsl[idx].length = length; 412 KASSERT(!((ract | dact | wact) & G_SLICE_HOT_START) 413 || gsp->start != NULL, ("G_SLICE_HOT_START but no slice->start")); 414 /* XXX: check that we _have_ a start function if HOT_START specified */ 415 gsl[idx].ract = ract; 416 gsl[idx].dact = dact; 417 gsl[idx].wact = wact; 418 return (0); 419} 420 421void 422g_slice_spoiled(struct g_consumer *cp) 423{ 424 struct g_geom *gp; 425 struct g_slicer *gsp; 426 427 g_topology_assert(); 428 gp = cp->geom; 429 g_trace(G_T_TOPOLOGY, "g_slice_spoiled(%p/%s)", cp, gp->name); 430 gsp = gp->softc; 431 gp->softc = NULL; 432 g_slice_free(gsp); 433 g_wither_geom(gp, ENXIO); 434} 435 436int 437g_slice_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp) 438{ 439 440 g_slice_spoiled(LIST_FIRST(&gp->consumer)); 441 return (0); 442} 443 444struct g_geom * 445g_slice_new(struct g_class *mp, u_int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start) 446{ 447 struct g_geom *gp; 448 struct g_slicer *gsp; 449 struct g_consumer *cp; 450 void **vp; 451 int error; 452 453 g_topology_assert(); 454 vp = (void **)extrap; 455 gp = g_new_geomf(mp, "%s", pp->name); 456 gsp = g_slice_alloc(slices, extra); 457 gsp->start = start; 458 gp->access = g_slice_access; 459 gp->orphan = g_slice_orphan; 460 gp->softc = gsp; 461 gp->start = g_slice_start; 462 gp->spoiled = g_slice_spoiled; 463 gp->dumpconf = g_slice_dumpconf; 464 if (gp->class->destroy_geom == NULL) 465 gp->class->destroy_geom = g_slice_destroy_geom; 466 cp = g_new_consumer(gp); 467 error = g_attach(cp, pp); 468 if (error == 0) 469 error = g_access(cp, 1, 0, 0); 470 if (error) { 471 g_wither_geom(gp, ENXIO); 472 return (NULL); 473 } 474 if (extrap != NULL) 475 *vp = gsp->softc; 476 *cpp = cp; 477 return (gp); 478} 479 480static void 481g_slice_orphan(struct g_consumer *cp) 482{ 483 484 g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name); 485 g_topology_assert(); 486 KASSERT(cp->provider->error != 0, 487 ("g_slice_orphan with error == 0")); 488 489 /* XXX: Not good enough we leak the softc and its suballocations */ 490 g_slice_free(cp->geom->softc); 491 g_wither_geom(cp->geom, cp->provider->error); 492} 493