sys/dev/disk/dm/targets/striped/dm_target_striped.c

   1 /*
   2  * Copyright (c) 2009 The NetBSD Foundation, Inc.
   3  * All rights reserved.
   4  *
   5  * This code is derived from software contributed to The NetBSD Foundation
   6  * by Adam Hamsik.
   7  *
   8  * This code is further derived from software contributed to the
   9  * DragonFly project by Alex Hornung and Matthew Dillon
  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  *
  20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  30  * POSSIBILITY OF SUCH DAMAGE.
  31  *
  32  * $NetBSD: dm_target_stripe.c,v 1.9 2010/01/04 00:14:41 haad Exp $
  33  */
  34
  35 /*
  36  * This file implements initial version of device-mapper stripe target.
  37  *
  38  * DragonFly changes: Increase to an unlimited number of stripes
  39  */
  40 #include <sys/types.h>
  41 #include <sys/param.h>
  42
  43 #include <sys/buf.h>
  44 #include <sys/malloc.h>
  45 #include <sys/vnode.h>
  46
  47 #include <dev/disk/dm/dm.h>
  48 MALLOC_DEFINE(M_DMSTRIPE, "dm_stripe", "Device Mapper Target Stripe");
  49
  50 static void dm_target_stripe_destroy_config(dm_target_stripe_config_t *tsc);
  51
  52 /*
  53  * Init function called from dm_table_load_ioctl.
  54  *
  55  * Example line sent to dm from lvm tools when using striped target.
  56  * start length striped #stripes chunk_size device1 offset1 ... deviceN offsetN
  57  * 0 65536 striped 2 512 /dev/hda 0 /dev/hdb 0
  58  */
  59 static int
  60 dm_target_stripe_init(dm_dev_t *dmv, void **target_config, char *params)
  61 {
  62         dm_target_stripe_config_t *tsc;
  63         int n;
  64         char *ap;
  65
  66         if (params == NULL)
  67                 return EINVAL;
  68
  69         /*
  70          * nstripes
  71          */
  72         ap = strsep(&params, " \t");
  73         if (ap == NULL)
  74                 return EINVAL;
  75         n = (int)atoi64(ap);
  76         if (n < 0 || n > MAX_STRIPES) {
  77                 kprintf("dm: Error %d stripes not supported (%d max)\n",
  78                         n, MAX_STRIPES);
  79                 return ENOTSUP;
  80         }
  81
  82         tsc = kmalloc(sizeof(dm_target_stripe_config_t),
  83                       M_DMSTRIPE, M_WAITOK | M_ZERO);
  84         tsc->stripe_num = n;
  85
  86         ap = strsep(&params, " \t");
  87         if (ap == NULL) {
  88                 dm_target_stripe_destroy_config(tsc);
  89                 return EINVAL;
  90         }
  91         tsc->stripe_chunksize = atoi64(ap);
  92         if (tsc->stripe_chunksize < 1 ||
  93             tsc->stripe_chunksize * DEV_BSIZE > MAXPHYS) {
  94                 kprintf("dm: Error unsupported chunk size %jdKB\n",
  95                         (intmax_t)tsc->stripe_chunksize * DEV_BSIZE / 1024);
  96                 dm_target_stripe_destroy_config(tsc);
  97                 return EINVAL;
  98         }
  99
 100         /*
 101          * Parse the devices
 102          */
 103
 104         kprintf("dm: Stripe %d devices chunk size %dKB\n",
 105                 (int)tsc->stripe_num,
 106                 (int)tsc->stripe_chunksize
 107         );
 108
 109         for (n = 0; n < tsc->stripe_num; ++n) {
 110                 ap = strsep(&params, " \t");
 111                 if (ap == NULL)
 112                         break;
 113                 tsc->stripe_devs[n].pdev = dm_pdev_insert(ap);
 114                 if (tsc->stripe_devs[n].pdev == NULL)
 115                         break;
 116                 ap = strsep(&params, " \t");
 117                 if (ap == NULL)
 118                         break;
 119                 tsc->stripe_devs[n].offset = atoi64(ap);
 120         }
 121         if (n != tsc->stripe_num) {
 122                 dm_target_stripe_destroy_config(tsc);
 123                 return (ENOENT);
 124         }
 125
 126         *target_config = tsc;
 127
 128         dmv->dev_type = DM_STRIPE_DEV;
 129
 130         return 0;
 131 }
 132
 133 /*
 134  * Status routine called to get params string.
 135  */
 136 static char *
 137 dm_target_stripe_status(void *target_config)
 138 {
 139         dm_target_stripe_config_t *tsc;
 140         char *params;
 141         char *ptr;
 142         size_t len;
 143         size_t nlen;
 144         int n;
 145
 146         tsc = target_config;
 147
 148         /* caller expects use of M_DM for returned params */
 149         nlen = DM_MAX_PARAMS_SIZE;
 150         params = kmalloc(nlen, M_DM, M_WAITOK);
 151         ptr = params;
 152
 153         ksnprintf(ptr, nlen, "%d %jd",
 154                   tsc->stripe_num, (intmax_t)tsc->stripe_chunksize);
 155         len = strlen(params);
 156         ptr += len;
 157         nlen -= len;
 158
 159         for (n = 0; n < tsc->stripe_num; ++n) {
 160                 ksnprintf(ptr, nlen, " %s %jd",
 161                           tsc->stripe_devs[n].pdev->name,
 162                           (intmax_t)tsc->stripe_devs[n].offset);
 163                 len = strlen(ptr);
 164                 ptr += len;
 165                 nlen -= len;
 166         }
 167
 168         return params;
 169 }
 170
 171 /*
 172  * Strategy routine called from dm_strategy.
 173  */
 174 static int
 175 dm_target_stripe_strategy(dm_table_entry_t *table_en, struct buf *bp)
 176 {
 177         dm_target_stripe_config_t *tsc;
 178         struct bio *bio = &bp->b_bio1;
 179         struct buf *nestbuf;
 180         uint64_t blkno, blkoff;
 181         uint64_t stripe, blknr;
 182         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 183         int devnr;
 184
 185         tsc = table_en->target_config;
 186         if (tsc == NULL)
 187                 return 0;
 188
 189         /* calculate extent of request */
 190         KKASSERT(bp->b_resid % DEV_BSIZE == 0);
 191
 192         switch(bp->b_cmd) {
 193         case BUF_CMD_READ:
 194         case BUF_CMD_WRITE:
 195         case BUF_CMD_FREEBLKS:
 196                 /*
 197                  * Loop through to individual operations
 198                  */
 199                 blkno = bp->b_bio1.bio_offset / DEV_BSIZE;
 200                 blkoff = 0;
 201                 num_blks = bp->b_resid / DEV_BSIZE;
 202                 nestiobuf_init(bio);
 203
 204                 while (num_blks > 0) {
 205                         /* blockno to strip piece nr */
 206                         stripe = blkno / tsc->stripe_chunksize;
 207                         stripe_off = blkno % tsc->stripe_chunksize;
 208
 209                         /* where we are inside the strip */
 210                         devnr = stripe % tsc->stripe_num;
 211                         blknr = stripe / tsc->stripe_num;
 212
 213                         /* how much is left before we hit a boundary */
 214                         stripe_rest = tsc->stripe_chunksize - stripe_off;
 215
 216                         /* issue this piece on stripe `stripe' */
 217                         issue_blks = MIN(stripe_rest, num_blks);
 218                         nestbuf = getpbuf(NULL);
 219                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 220
 221                         nestiobuf_add(bio, nestbuf, blkoff,
 222                                         issue_blks * DEV_BSIZE, NULL);
 223
 224                         /* I need number of bytes. */
 225                         nestbuf->b_bio1.bio_offset =
 226                                 blknr * tsc->stripe_chunksize + stripe_off;
 227                         nestbuf->b_bio1.bio_offset +=
 228                                 tsc->stripe_devs[devnr].offset;
 229                         nestbuf->b_bio1.bio_offset *= DEV_BSIZE;
 230
 231                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 232                                     &nestbuf->b_bio1);
 233
 234                         blkno += issue_blks;
 235                         blkoff += issue_blks * DEV_BSIZE;
 236                         num_blks -= issue_blks;
 237                 }
 238                 nestiobuf_start(bio);
 239                 break;
 240         case BUF_CMD_FLUSH:
 241                 nestiobuf_init(bio);
 242                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 243                         nestbuf = getpbuf(NULL);
 244                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 245
 246                         nestiobuf_add(bio, nestbuf, 0, 0, NULL);
 247                         nestbuf->b_bio1.bio_offset = 0;
 248                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 249                                     &nestbuf->b_bio1);
 250                 }
 251                 nestiobuf_start(bio);
 252                 break;
 253         default:
 254                 bp->b_flags |= B_ERROR;
 255                 bp->b_error = EIO;
 256                 biodone(bio);
 257                 break;
 258         }
 259         return 0;
 260 }
 261
 262
 263 static int
 264 dm_target_stripe_dump(dm_table_entry_t *table_en, void *data, size_t length, off_t offset)
 265 {
 266         dm_target_stripe_config_t *tsc;
 267         uint64_t blkno, blkoff;
 268         uint64_t stripe, blknr;
 269         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 270         uint64_t off2, len2;
 271         int devnr;
 272
 273         tsc = table_en->target_config;
 274         if (tsc == NULL)
 275                 return 0;
 276
 277         /* calculate extent of request */
 278         KKASSERT(length % DEV_BSIZE == 0);
 279
 280         blkno = offset / DEV_BSIZE;
 281         blkoff = 0;
 282         num_blks = length / DEV_BSIZE;
 283
 284         /*
 285          * 0 length means flush buffers and return
 286          */
 287         if (length == 0) {
 288                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 289                         if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 290                                 return ENXIO;
 291
 292                         dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 293                             data, 0, offset, 0);
 294                 }
 295                 return 0;
 296         }
 297
 298         while (num_blks > 0) {
 299                 /* blockno to strip piece nr */
 300                 stripe = blkno / tsc->stripe_chunksize;
 301                 stripe_off = blkno % tsc->stripe_chunksize;
 302
 303                 /* where we are inside the strip */
 304                 devnr = stripe % tsc->stripe_num;
 305                 blknr = stripe / tsc->stripe_num;
 306
 307                 /* how much is left before we hit a boundary */
 308                 stripe_rest = tsc->stripe_chunksize - stripe_off;
 309
 310                 /* issue this piece on stripe `stripe' */
 311                 issue_blks = MIN(stripe_rest, num_blks);
 312
 313 #if 0
 314                 nestiobuf_add(bio, nestbuf, blkoff,
 315                                 issue_blks * DEV_BSIZE);
 316 #endif
 317                 len2 = issue_blks * DEV_BSIZE;
 318
 319                 /* I need number of bytes. */
 320                 off2 = blknr * tsc->stripe_chunksize + stripe_off;
 321                 off2 += tsc->stripe_devs[devnr].offset;
 322                 off2 *= DEV_BSIZE;
 323                 off2 = dm_pdev_correct_dump_offset(tsc->stripe_devs[devnr].pdev,
 324                     off2);
 325
 326                 if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 327                         return ENXIO;
 328
 329                 dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 330                     (char *)data + blkoff, 0, off2, len2);
 331
 332                 blkno += issue_blks;
 333                 blkoff += issue_blks * DEV_BSIZE;
 334                 num_blks -= issue_blks;
 335         }
 336
 337         return 0;
 338 }
 339
 340 /*
 341  * Destroy a dm table entry for stripes.
 342  */
 343 static int
 344 dm_target_stripe_destroy(dm_table_entry_t *table_en)
 345 {
 346         dm_target_stripe_config_t *tsc;
 347
 348         if ((tsc = table_en->target_config) != NULL) {
 349                 table_en->target_config = NULL;
 350                 dm_target_stripe_destroy_config(tsc);
 351         }
 352
 353         return 0;
 354 }
 355
 356 static void
 357 dm_target_stripe_destroy_config(dm_target_stripe_config_t *tsc)
 358 {
 359         int n;
 360
 361         for (n = 0; n < tsc->stripe_num; ++n) {
 362                 if (tsc->stripe_devs[n].pdev) {
 363                         dm_pdev_decr(tsc->stripe_devs[n].pdev);
 364                         tsc->stripe_devs[n].pdev = NULL;
 365                 }
 366         }
 367         kfree(tsc, M_DMSTRIPE);
 368 }
 369
 370 /*
 371  * Generate properties from stripe table entry.
 372  */
 373 static int
 374 dm_target_stripe_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
 375 {
 376         dm_target_stripe_config_t *tsc;
 377         struct vattr va;
 378         int error;
 379         int n;
 380
 381         if (table_en->target_config == NULL)
 382                 return ENOENT;
 383
 384         tsc = table_en->target_config;
 385         error = 0;
 386         for (n = 0; n < tsc->stripe_num; ++n) {
 387                 error = VOP_GETATTR(tsc->stripe_devs[n].pdev->pdev_vnode, &va);
 388                 if (error)
 389                         break;
 390                 prop_array_add_uint64(prop_array,
 391                                 (uint64_t)makeudev(va.va_rmajor, va.va_rminor));
 392         }
 393         return (error);
 394 }
 395
 396 /*
 397  * Unsupported for this target.
 398  */
 399 static int
 400 dm_target_stripe_upcall(dm_table_entry_t * table_en, struct buf * bp)
 401 {
 402         return 0;
 403 }
 404
 405 static int
 406 dmts_mod_handler(module_t mod, int type, void *unused)
 407 {
 408         dm_target_t *dmt = NULL;
 409         int err = 0;
 410
 411         switch(type) {
 412         case MOD_LOAD:
 413                 if ((dmt = dm_target_lookup("striped")) != NULL) {
 414                         dm_target_unbusy(dmt);
 415                         return EEXIST;
 416                 }
 417                 dmt = dm_target_alloc("striped");
 418                 dmt->version[0] = 1;
 419                 dmt->version[1] = 0;
 420                 dmt->version[2] = 3;
 421                 strlcpy(dmt->name, "striped", DM_MAX_TYPE_NAME);
 422                 dmt->init = &dm_target_stripe_init;
 423                 dmt->status = &dm_target_stripe_status;
 424                 dmt->strategy = &dm_target_stripe_strategy;
 425                 dmt->deps = &dm_target_stripe_deps;
 426                 dmt->destroy = &dm_target_stripe_destroy;
 427                 dmt->upcall = &dm_target_stripe_upcall;
 428                 dmt->dump = &dm_target_stripe_dump;
 429
 430                 err = dm_target_insert(dmt);
 431                 if (err == 0)
 432                         kprintf("dm_target_stripe: Successfully initialized\n");
 433                 break;
 434
 435         case MOD_UNLOAD:
 436                 err = dm_target_rem("striped");
 437                 if (err == 0)
 438                         kprintf("dm_target_stripe: unloaded\n");
 439                 break;
 440
 441         default:
 442                 break;
 443         }
 444
 445         return err;
 446 }
 447
 448 DM_TARGET_MODULE(dm_target_striped, dmts_mod_handler);