1 /* 2 * ---------------------------------------------------------------------------- 3 * "THE BEER-WARE LICENSE" (Revision 42): 4 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you 5 * can do whatever you want with this stuff. If we meet some day, and you think 6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 7 * ---------------------------------------------------------------------------- 8 * 9 * $FreeBSD$ 10 * 11 */ 12 13 #include "opt_mfs.h" /* We have adopted some tasks from MFS */ 14 #include "opt_md.h" /* We have adopted some tasks from MFS */ 15 16 #include <sys/param.h> 17 #include <sys/systm.h> 18 #include <sys/bio.h> 19 #include <sys/conf.h> 20 #include <sys/devicestat.h> 21 #include <sys/disk.h> 22 #include <sys/kernel.h> 23 #include <sys/malloc.h> 24 #include <sys/sysctl.h> 25 #include <sys/linker.h> 26 27 #ifndef MD_NSECT 28 #define MD_NSECT (10000 * 2) 29 #endif 30 31 MALLOC_DEFINE(M_MD, "MD disk", "Memory Disk"); 32 MALLOC_DEFINE(M_MDSECT, "MD sectors", "Memory Disk Sectors"); 33 34 static int md_debug; 35 SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, ""); 36 37 #if defined(MFS_ROOT) && !defined(MD_ROOT) 38 #define MD_ROOT MFS_ROOT 39 #warning "option MFS_ROOT has been superceeded by MD_ROOT" 40 #endif 41 42 #if defined(MFS_ROOT_SIZE) && !defined(MD_ROOT_SIZE) 43 #define MD_ROOT_SIZE MFS_ROOT_SIZE 44 #warning "option MFS_ROOT_SIZE has been superceeded by MD_ROOT_SIZE" 45 #endif 46 47 #if defined(MD_ROOT) && defined(MD_ROOT_SIZE) 48 /* Image gets put here: */ 49 static u_char mfs_root[MD_ROOT_SIZE*1024] = "MFS Filesystem goes here"; 50 static u_char end_mfs_root[] __unused = "MFS Filesystem had better STOP here"; 51 #endif 52 53 static int mdrootready; 54 55 static void mdcreate_malloc(void); 56 57 #define CDEV_MAJOR 95 58 #define BDEV_MAJOR 22 59 60 static d_strategy_t mdstrategy; 61 static d_strategy_t mdstrategy_preload; 62 static d_strategy_t mdstrategy_malloc; 63 static d_open_t mdopen; 64 static d_ioctl_t mdioctl; 65 66 static struct cdevsw md_cdevsw = { 67 /* open */ mdopen, 68 /* close */ nullclose, 69 /* read */ physread, 70 /* write */ physwrite, 71 /* ioctl */ mdioctl, 72 /* poll */ nopoll, 73 /* mmap */ nommap, 74 /* strategy */ mdstrategy, 75 /* name */ "md", 76 /* maj */ CDEV_MAJOR, 77 /* dump */ nodump, 78 /* psize */ nopsize, 79 /* flags */ D_DISK | D_CANFREE | D_MEMDISK, 80 /* bmaj */ BDEV_MAJOR 81 }; 82 83 static struct cdevsw mddisk_cdevsw; 84 85 struct md_s { 86 int unit; 87 struct devstat stats; 88 struct bio_queue_head bio_queue; 89 struct disk disk; 90 dev_t dev; 91 int busy; 92 enum {MD_MALLOC, MD_PRELOAD} type; 93 unsigned nsect; 94 95 /* MD_MALLOC related fields */ 96 unsigned nsecp; 97 u_char **secp; 98 99 /* MD_PRELOAD related fields */ 100 u_char *pl_ptr; 101 unsigned pl_len; 102 }; 103 104 static int mdunits; 105 106 static int 107 mdopen(dev_t dev, int flag, int fmt, struct proc *p) 108 { 109 struct md_s *sc; 110 struct disklabel *dl; 111 112 if (md_debug) 113 printf("mdopen(%s %x %x %p)\n", 114 devtoname(dev), flag, fmt, p); 115 116 sc = dev->si_drv1; 117 if (sc->unit + 1 == mdunits) 118 mdcreate_malloc(); 119 120 dl = &sc->disk.d_label; 121 bzero(dl, sizeof(*dl)); 122 dl->d_secsize = DEV_BSIZE; 123 dl->d_nsectors = 1024; 124 dl->d_ntracks = 1; 125 dl->d_secpercyl = dl->d_nsectors * dl->d_ntracks; 126 dl->d_secperunit = sc->nsect; 127 dl->d_ncylinders = dl->d_secperunit / dl->d_secpercyl; 128 return (0); 129 } 130 131 static int 132 mdioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p) 133 { 134 135 if (md_debug) 136 printf("mdioctl(%s %lx %p %x %p)\n", 137 devtoname(dev), cmd, addr, flags, p); 138 139 return (ENOIOCTL); 140 } 141 142 static void 143 mdstrategy(struct bio *bp) 144 { 145 struct md_s *sc; 146 147 if (md_debug > 1) 148 printf("mdstrategy(%p) %s %x, %d, %ld, %p)\n", 149 bp, devtoname(bp->bio_dev), bp->bio_flags, bp->bio_blkno, 150 bp->bio_bcount / DEV_BSIZE, bp->bio_data); 151 152 sc = bp->bio_dev->si_drv1; 153 if (sc->type == MD_MALLOC) { 154 mdstrategy_malloc(bp); 155 } else { 156 mdstrategy_preload(bp); 157 } 158 return; 159 } 160 161 162 static void 163 mdstrategy_malloc(struct bio *bp) 164 { 165 int s, i; 166 struct md_s *sc; 167 devstat_trans_flags dop; 168 u_char *secp, **secpp, *dst; 169 unsigned secno, nsec, secval, uc; 170 171 if (md_debug > 1) 172 printf("mdstrategy_malloc(%p) %s %x, %d, %ld, %p)\n", 173 bp, devtoname(bp->bio_dev), bp->bio_flags, bp->bio_blkno, 174 bp->bio_bcount / DEV_BSIZE, bp->bio_data); 175 176 sc = bp->bio_dev->si_drv1; 177 178 s = splbio(); 179 180 bioqdisksort(&sc->bio_queue, bp); 181 182 if (sc->busy) { 183 splx(s); 184 return; 185 } 186 187 sc->busy++; 188 189 while (1) { 190 bp = bioq_first(&sc->bio_queue); 191 if (bp) 192 bioq_remove(&sc->bio_queue, bp); 193 splx(s); 194 if (!bp) 195 break; 196 197 devstat_start_transaction(&sc->stats); 198 199 if (bp->bio_cmd == BIO_DELETE) 200 dop = DEVSTAT_NO_DATA; 201 else if (bp->bio_cmd == BIO_READ) 202 dop = DEVSTAT_READ; 203 else 204 dop = DEVSTAT_WRITE; 205 206 nsec = bp->bio_bcount / DEV_BSIZE; 207 secno = bp->bio_pblkno; 208 dst = bp->bio_data; 209 while (nsec--) { 210 211 if (secno < sc->nsecp) { 212 secpp = &sc->secp[secno]; 213 if ((u_int)*secpp > 255) { 214 secp = *secpp; 215 secval = 0; 216 } else { 217 secp = 0; 218 secval = (u_int) *secpp; 219 } 220 } else { 221 secpp = 0; 222 secp = 0; 223 secval = 0; 224 } 225 if (md_debug > 2) 226 printf("%x %p %p %d\n", 227 bp->bio_flags, secpp, secp, secval); 228 229 if (bp->bio_cmd == BIO_DELETE) { 230 if (secpp) { 231 if (secp) 232 FREE(secp, M_MDSECT); 233 *secpp = 0; 234 } 235 } else if (bp->bio_cmd == BIO_READ) { 236 if (secp) { 237 bcopy(secp, dst, DEV_BSIZE); 238 } else if (secval) { 239 for (i = 0; i < DEV_BSIZE; i++) 240 dst[i] = secval; 241 } else { 242 bzero(dst, DEV_BSIZE); 243 } 244 } else { 245 uc = dst[0]; 246 for (i = 1; i < DEV_BSIZE; i++) 247 if (dst[i] != uc) 248 break; 249 if (i == DEV_BSIZE && !uc) { 250 if (secp) 251 FREE(secp, M_MDSECT); 252 if (secpp) 253 *secpp = (u_char *)uc; 254 } else { 255 if (!secpp) { 256 MALLOC(secpp, u_char **, (secno + nsec + 1) * sizeof(u_char *), M_MD, M_WAITOK); 257 bzero(secpp, (secno + nsec + 1) * sizeof(u_char *)); 258 bcopy(sc->secp, secpp, sc->nsecp * sizeof(u_char *)); 259 FREE(sc->secp, M_MD); 260 sc->secp = secpp; 261 sc->nsecp = secno + nsec + 1; 262 secpp = &sc->secp[secno]; 263 } 264 if (i == DEV_BSIZE) { 265 if (secp) 266 FREE(secp, M_MDSECT); 267 *secpp = (u_char *)uc; 268 } else { 269 if (!secp) 270 MALLOC(secp, u_char *, DEV_BSIZE, M_MDSECT, M_WAITOK); 271 bcopy(dst, secp, DEV_BSIZE); 272 273 *secpp = secp; 274 } 275 } 276 } 277 secno++; 278 dst += DEV_BSIZE; 279 } 280 bp->bio_resid = 0; 281 devstat_end_transaction_bio(&sc->stats, bp); 282 biodone(bp); 283 s = splbio(); 284 } 285 sc->busy = 0; 286 return; 287 } 288 289 290 static void 291 mdstrategy_preload(struct bio *bp) 292 { 293 int s; 294 struct md_s *sc; 295 devstat_trans_flags dop; 296 297 if (md_debug > 1) 298 printf("mdstrategy_preload(%p) %s %x, %d, %ld, %p)\n", 299 bp, devtoname(bp->bio_dev), bp->bio_flags, bp->bio_blkno, 300 bp->bio_bcount / DEV_BSIZE, bp->bio_data); 301 302 sc = bp->bio_dev->si_drv1; 303 304 s = splbio(); 305 306 bioqdisksort(&sc->bio_queue, bp); 307 308 if (sc->busy) { 309 splx(s); 310 return; 311 } 312 313 sc->busy++; 314 315 while (1) { 316 bp = bioq_first(&sc->bio_queue); 317 if (bp) 318 bioq_remove(&sc->bio_queue, bp); 319 splx(s); 320 if (!bp) 321 break; 322 323 devstat_start_transaction(&sc->stats); 324 325 if (bp->bio_cmd == BIO_DELETE) { 326 dop = DEVSTAT_NO_DATA; 327 } else if (bp->bio_cmd == BIO_READ) { 328 dop = DEVSTAT_READ; 329 bcopy(sc->pl_ptr + (bp->bio_pblkno << DEV_BSHIFT), bp->bio_data, bp->bio_bcount); 330 } else { 331 dop = DEVSTAT_WRITE; 332 bcopy(bp->bio_data, sc->pl_ptr + (bp->bio_pblkno << DEV_BSHIFT), bp->bio_bcount); 333 } 334 bp->bio_resid = 0; 335 devstat_end_transaction_bio(&sc->stats, bp); 336 biodone(bp); 337 s = splbio(); 338 } 339 sc->busy = 0; 340 return; 341 } 342 343 static struct md_s * 344 mdcreate(void) 345 { 346 struct md_s *sc; 347 348 MALLOC(sc, struct md_s *,sizeof(*sc), M_MD, M_WAITOK); 349 bzero(sc, sizeof(*sc)); 350 sc->unit = mdunits++; 351 bioq_init(&sc->bio_queue); 352 devstat_add_entry(&sc->stats, "md", sc->unit, DEV_BSIZE, 353 DEVSTAT_NO_ORDERED_TAGS, 354 DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER, 355 DEVSTAT_PRIORITY_OTHER); 356 sc->dev = disk_create(sc->unit, &sc->disk, 0, &md_cdevsw, &mddisk_cdevsw); 357 sc->dev->si_drv1 = sc; 358 return (sc); 359 } 360 361 static void 362 mdcreate_preload(u_char *image, unsigned length) 363 { 364 struct md_s *sc; 365 366 sc = mdcreate(); 367 sc->type = MD_PRELOAD; 368 sc->nsect = length / DEV_BSIZE; 369 sc->pl_ptr = image; 370 sc->pl_len = length; 371 372 if (sc->unit == 0) 373 mdrootready = 1; 374 } 375 376 static void 377 mdcreate_malloc(void) 378 { 379 struct md_s *sc; 380 381 sc = mdcreate(); 382 sc->type = MD_MALLOC; 383 384 sc->nsect = MD_NSECT; /* for now */ 385 MALLOC(sc->secp, u_char **, sizeof(u_char *), M_MD, M_WAITOK); 386 bzero(sc->secp, sizeof(u_char *)); 387 sc->nsecp = 1; 388 printf("md%d: Malloc disk\n", sc->unit); 389 } 390 391 static void 392 md_drvinit(void *unused) 393 { 394 395 caddr_t mod; 396 caddr_t c; 397 u_char *ptr, *name, *type; 398 unsigned len; 399 400 #ifdef MD_ROOT_SIZE 401 mdcreate_preload(mfs_root, MD_ROOT_SIZE*1024); 402 #endif 403 mod = NULL; 404 while ((mod = preload_search_next_name(mod)) != NULL) { 405 name = (char *)preload_search_info(mod, MODINFO_NAME); 406 type = (char *)preload_search_info(mod, MODINFO_TYPE); 407 if (name == NULL) 408 continue; 409 if (type == NULL) 410 continue; 411 if (strcmp(type, "md_image") && strcmp(type, "mfs_root")) 412 continue; 413 c = preload_search_info(mod, MODINFO_ADDR); 414 ptr = *(u_char **)c; 415 c = preload_search_info(mod, MODINFO_SIZE); 416 len = *(unsigned *)c; 417 printf("md%d: Preloaded image <%s> %d bytes at %p\n", 418 mdunits, name, len, ptr); 419 mdcreate_preload(ptr, len); 420 } 421 mdcreate_malloc(); 422 } 423 424 SYSINIT(mddev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR, md_drvinit,NULL) 425 426 #ifdef MD_ROOT 427 static void 428 md_takeroot(void *junk) 429 { 430 if (mdrootready) 431 rootdevnames[0] = "ufs:/dev/md0c"; 432 } 433 434 SYSINIT(md_root, SI_SUB_MOUNT_ROOT, SI_ORDER_FIRST, md_takeroot, NULL); 435 #endif 436