geom_slice.c revision 113878
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_slice.c 113878 2003-04-22 21:19:17Z phk $ 36 */ 37 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_init(unsigned nslice, unsigned scsize) 61{ 62 struct g_slicer *gsp; 63 64 gsp = g_malloc(sizeof *gsp, M_WAITOK | M_ZERO); 65 gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO); 66 gsp->slices = g_malloc(nslice * sizeof(struct g_slice), 67 M_WAITOK | M_ZERO); 68 gsp->nslice = nslice; 69 return (gsp); 70} 71 72static int 73g_slice_access(struct g_provider *pp, int dr, int dw, int de) 74{ 75 int error; 76 u_int u; 77 struct g_geom *gp; 78 struct g_consumer *cp; 79 struct g_provider *pp2; 80 struct g_slicer *gsp; 81 struct g_slice *gsl, *gsl2; 82 83 gp = pp->geom; 84 cp = LIST_FIRST(&gp->consumer); 85 KASSERT (cp != NULL, ("g_slice_access but no consumer")); 86 gsp = gp->softc; 87 gsl = &gsp->slices[pp->index]; 88 for (u = 0; u < gsp->nslice; u++) { 89 gsl2 = &gsp->slices[u]; 90 if (gsl2->length == 0) 91 continue; 92 if (u == pp->index) 93 continue; 94 if (gsl->offset + gsl->length <= gsl2->offset) 95 continue; 96 if (gsl2->offset + gsl2->length <= gsl->offset) 97 continue; 98 /* overlap */ 99 pp2 = gsl2->provider; 100 if ((pp->acw + dw) > 0 && pp2->ace > 0) 101 return (EPERM); 102 if ((pp->ace + de) > 0 && pp2->acw > 0) 103 return (EPERM); 104 } 105 /* On first open, grab an extra "exclusive" bit */ 106 if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) 107 de++; 108 /* ... and let go of it on last close */ 109 if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) 110 de--; 111 error = g_access_rel(cp, dr, dw, de); 112 return (error); 113} 114 115/* 116 * XXX: It should be possible to specify here if we should finish all of the 117 * XXX: bio, or only the non-hot bits. This would get messy if there were 118 * XXX: two hot spots in the same bio, so for now we simply finish off the 119 * XXX: entire bio. Modifying hot data on the way to disk is frowned on 120 * XXX: so making that considerably harder is not a bad idea anyway. 121 */ 122void 123g_slice_finish_hot(struct bio *bp) 124{ 125 struct bio *bp2; 126 struct g_geom *gp; 127 struct g_consumer *cp; 128 struct g_slicer *gsp; 129 struct g_slice *gsl; 130 int idx; 131 132 KASSERT(bp->bio_to != NULL, 133 ("NULL bio_to in g_slice_finish_hot(%p)", bp)); 134 KASSERT(bp->bio_from != NULL, 135 ("NULL bio_from in g_slice_finish_hot(%p)", bp)); 136 gp = bp->bio_to->geom; 137 gsp = gp->softc; 138 cp = LIST_FIRST(&gp->consumer); 139 KASSERT(cp != NULL, ("NULL consumer in g_slice_finish_hot(%p)", bp)); 140 idx = bp->bio_to->index; 141 gsl = &gsp->slices[idx]; 142 143 bp2 = g_clone_bio(bp); 144 if (bp2 == NULL) { 145 g_io_deliver(bp, ENOMEM); 146 return; 147 } 148 if (bp2->bio_offset + bp2->bio_length > gsl->length) 149 bp2->bio_length = gsl->length - bp2->bio_offset; 150 bp2->bio_done = g_std_done; 151 bp2->bio_offset += gsl->offset; 152 g_io_request(bp2, cp); 153 return; 154} 155 156static void 157g_slice_start(struct bio *bp) 158{ 159 struct bio *bp2; 160 struct g_provider *pp; 161 struct g_geom *gp; 162 struct g_consumer *cp; 163 struct g_slicer *gsp; 164 struct g_slice *gsl; 165 struct g_slice_hot *ghp; 166 int idx, error; 167 u_int m_index; 168 off_t t; 169 170 pp = bp->bio_to; 171 gp = pp->geom; 172 gsp = gp->softc; 173 cp = LIST_FIRST(&gp->consumer); 174 idx = pp->index; 175 gsl = &gsp->slices[idx]; 176 switch(bp->bio_cmd) { 177 case BIO_READ: 178 case BIO_WRITE: 179 case BIO_DELETE: 180 if (bp->bio_offset > gsl->length) { 181 g_io_deliver(bp, EINVAL); /* XXX: EWHAT ? */ 182 return; 183 } 184 /* 185 * Check if we collide with any hot spaces, and call the 186 * method once if so. 187 */ 188 t = bp->bio_offset + gsl->offset; 189 for (m_index = 0; m_index < gsp->nhotspot; m_index++) { 190 ghp = &gsp->hotspot[m_index]; 191 if (t >= ghp->offset + ghp->length) 192 continue; 193 if (t + bp->bio_length <= ghp->offset) 194 continue; 195 switch(bp->bio_cmd) { 196 case BIO_READ: idx = ghp->ract; break; 197 case BIO_WRITE: idx = ghp->wact; break; 198 case BIO_DELETE: idx = ghp->dact; break; 199 } 200 switch(idx) { 201 case G_SLICE_HOT_ALLOW: 202 /* Fall out and continue normal processing */ 203 continue; 204 case G_SLICE_HOT_DENY: 205 g_io_deliver(bp, EROFS); 206 return; 207 case G_SLICE_HOT_START: 208 error = gsp->start(bp); 209 if (error && error != EJUSTRETURN) 210 g_io_deliver(bp, error); 211 return; 212 case G_SLICE_HOT_CALL: 213 error = g_call_me(gsp->hot, bp, gp, NULL); 214 if (error) 215 g_io_deliver(bp, error); 216 return; 217 } 218 break; 219 } 220 bp2 = g_clone_bio(bp); 221 if (bp2 == NULL) { 222 g_io_deliver(bp, ENOMEM); 223 return; 224 } 225 if (bp2->bio_offset + bp2->bio_length > gsl->length) 226 bp2->bio_length = gsl->length - bp2->bio_offset; 227 bp2->bio_done = g_std_done; 228 bp2->bio_offset += gsl->offset; 229 g_io_request(bp2, cp); 230 return; 231 case BIO_GETATTR: 232 /* Give the real method a chance to override */ 233 if (gsp->start != NULL && gsp->start(bp)) 234 return; 235 if (!strcmp("GEOM::kerneldump", bp->bio_attribute)) { 236 struct g_kerneldump *gkd; 237 238 gkd = (struct g_kerneldump *)bp->bio_data; 239 gkd->offset += gsp->slices[idx].offset; 240 if (gkd->length > gsp->slices[idx].length) 241 gkd->length = gsp->slices[idx].length; 242 /* now, pass it on downwards... */ 243 } 244 bp2 = g_clone_bio(bp); 245 if (bp2 == NULL) { 246 g_io_deliver(bp, ENOMEM); 247 return; 248 } 249 bp2->bio_done = g_std_done; 250 g_io_request(bp2, cp); 251 break; 252 default: 253 g_io_deliver(bp, EOPNOTSUPP); 254 return; 255 } 256} 257 258void 259g_slice_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp) 260{ 261 struct g_slicer *gsp; 262 263 gsp = gp->softc; 264 if (indent == NULL) { 265 sbuf_printf(sb, " i %u", pp->index); 266 sbuf_printf(sb, " o %ju", 267 (uintmax_t)gsp->slices[pp->index].offset); 268 return; 269 } 270 if (pp != NULL) { 271 sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index); 272 sbuf_printf(sb, "%s<length>%ju</length>\n", 273 indent, (uintmax_t)gsp->slices[pp->index].length); 274 sbuf_printf(sb, "%s<seclength>%ju</seclength>\n", indent, 275 (uintmax_t)gsp->slices[pp->index].length / 512); 276 sbuf_printf(sb, "%s<offset>%ju</offset>\n", indent, 277 (uintmax_t)gsp->slices[pp->index].offset); 278 sbuf_printf(sb, "%s<secoffset>%ju</secoffset>\n", indent, 279 (uintmax_t)gsp->slices[pp->index].offset / 512); 280 } 281} 282 283int 284g_slice_config(struct g_geom *gp, u_int idx, int how, off_t offset, off_t length, u_int sectorsize, const char *fmt, ...) 285{ 286 struct g_provider *pp, *pp2; 287 struct g_slicer *gsp; 288 struct g_slice *gsl; 289 va_list ap; 290 struct sbuf *sb; 291 int error, acc; 292 293 g_trace(G_T_TOPOLOGY, "g_slice_config(%s, %d, %d)", 294 gp->name, idx, how); 295 g_topology_assert(); 296 gsp = gp->softc; 297 error = 0; 298 if (idx >= gsp->nslice) 299 return(EINVAL); 300 gsl = &gsp->slices[idx]; 301 pp = gsl->provider; 302 if (pp != NULL) 303 acc = pp->acr + pp->acw + pp->ace; 304 else 305 acc = 0; 306 if (acc != 0 && how != G_SLICE_CONFIG_FORCE) { 307 if (length < gsl->length) 308 return(EBUSY); 309 if (offset != gsl->offset) 310 return(EBUSY); 311 } 312 /* XXX: check offset + length <= MEDIASIZE */ 313 if (how == G_SLICE_CONFIG_CHECK) 314 return (0); 315 gsl->length = length; 316 gsl->offset = offset; 317 gsl->sectorsize = sectorsize; 318 if (length == 0) { 319 if (pp == NULL) 320 return (0); 321 if (bootverbose) 322 printf("GEOM: Deconfigure %s\n", pp->name); 323 g_orphan_provider(pp, ENXIO); 324 gsl->provider = NULL; 325 gsp->nprovider--; 326 return (0); 327 } 328 if (pp != NULL) { 329 if (bootverbose) 330 printf("GEOM: Reconfigure %s, start %jd length %jd end %jd\n", 331 pp->name, (intmax_t)offset, (intmax_t)length, 332 (intmax_t)(offset + length - 1)); 333 pp->mediasize = gsl->length; 334 return (0); 335 } 336 va_start(ap, fmt); 337 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 338 sbuf_vprintf(sb, fmt, ap); 339 sbuf_finish(sb); 340 pp = g_new_providerf(gp, sbuf_data(sb)); 341 pp2 = LIST_FIRST(&gp->consumer)->provider; 342 pp->flags = pp2->flags & G_PF_CANDELETE; 343 if (pp2->stripesize > 0) { 344 pp->stripesize = pp2->stripesize; 345 pp->stripeoffset = (pp2->stripeoffset + offset) % pp->stripesize; 346 } 347 if (bootverbose) 348 printf("GEOM: Configure %s, start %jd length %jd end %jd\n", 349 pp->name, (intmax_t)offset, (intmax_t)length, 350 (intmax_t)(offset + length - 1)); 351 pp->index = idx; 352 pp->mediasize = gsl->length; 353 pp->sectorsize = gsl->sectorsize; 354 gsl->provider = pp; 355 gsp->nprovider++; 356 g_error_provider(pp, 0); 357 sbuf_delete(sb); 358 return(0); 359} 360 361/* 362 * Configure "hotspots". A hotspot is a piece of the parent device which 363 * this particular slicer cares about for some reason. Typically because 364 * it contains meta-data used to configure the slicer. 365 * A hotspot is identified by its index number. The offset and length are 366 * relative to the parent device, and the three "?act" fields specify 367 * what action to take on BIO_READ, BIO_DELETE and BIO_WRITE. 368 * 369 * XXX: There may be a race relative to g_slice_start() here, if an existing 370 * XXX: hotspot is changed wile I/O is happening. Should this become a problem 371 * XXX: we can protect the hotspot stuff with a mutex. 372 */ 373 374int 375g_slice_conf_hot(struct g_geom *gp, u_int idx, off_t offset, off_t length, int ract, int dact, int wact) 376{ 377 struct g_slicer *gsp; 378 struct g_slice_hot *gsl, *gsl2; 379 380 g_trace(G_T_TOPOLOGY, "g_slice_conf_hot(%s, idx: %d, off: %jd, len: %jd)", 381 gp->name, idx, (intmax_t)offset, (intmax_t)length); 382 g_topology_assert(); 383 gsp = gp->softc; 384 gsl = gsp->hotspot; 385 if(idx >= gsp->nhotspot) { 386 gsl2 = g_malloc((idx + 1) * sizeof *gsl2, M_WAITOK | M_ZERO); 387 if (gsp->hotspot != NULL) 388 bcopy(gsp->hotspot, gsl2, gsp->nhotspot * sizeof *gsl2); 389 gsp->hotspot = gsl2; 390 if (gsp->hotspot != NULL) 391 g_free(gsl); 392 gsl = gsl2; 393 gsp->nhotspot = idx + 1; 394 } 395 gsl[idx].offset = offset; 396 gsl[idx].length = length; 397 KASSERT(!((ract | dact | wact) & G_SLICE_HOT_START) 398 || gsp->start != NULL, ("G_SLICE_HOT_START but no slice->start")); 399 /* XXX: check that we _have_ a start function if HOT_START specified */ 400 gsl[idx].ract = ract; 401 gsl[idx].dact = dact; 402 gsl[idx].wact = wact; 403 return (0); 404} 405 406struct g_geom * 407g_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) 408{ 409 struct g_geom *gp; 410 struct g_slicer *gsp; 411 struct g_consumer *cp; 412 void **vp; 413 int error; 414 415 g_topology_assert(); 416 vp = (void **)extrap; 417 gp = g_new_geomf(mp, "%s", pp->name); 418 gsp = g_slice_init(slices, extra); 419 gsp->start = start; 420 gp->access = g_slice_access; 421 gp->orphan = g_slice_orphan; 422 gp->softc = gsp; 423 gp->start = g_slice_start; 424 gp->spoiled = g_std_spoiled; 425 gp->dumpconf = g_slice_dumpconf; 426 cp = g_new_consumer(gp); 427 error = g_attach(cp, pp); 428 if (error == 0) 429 error = g_access_rel(cp, 1, 0, 0); 430 if (error) { 431 if (cp->provider != NULL) 432 g_detach(cp); 433 g_destroy_consumer(cp); 434 g_free(gsp->slices); 435 g_free(gp->softc); 436 g_destroy_geom(gp); 437 return (NULL); 438 } 439 *vp = gsp->softc; 440 *cpp = cp; 441 return (gp); 442} 443 444static void 445g_slice_orphan(struct g_consumer *cp) 446{ 447 struct g_geom *gp; 448 struct g_provider *pp; 449 int error; 450 451 g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name); 452 g_topology_assert(); 453 KASSERT(cp->provider->error != 0, 454 ("g_slice_orphan with error == 0")); 455 456 gp = cp->geom; 457 /* XXX: Not good enough we leak the softc and its suballocations */ 458 gp->flags |= G_GEOM_WITHER; 459 error = cp->provider->error; 460 LIST_FOREACH(pp, &gp->provider, provider) 461 g_orphan_provider(pp, error); 462 return; 463} 464