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                 return EINVAL;
  89         tsc->stripe_chunksize = atoi64(ap);
  90         if (tsc->stripe_chunksize < 1 ||
  91             tsc->stripe_chunksize * DEV_BSIZE > MAXPHYS) {
  92                 kprintf("dm: Error unsupported chunk size %jdKB\n",
  93                         (intmax_t)tsc->stripe_chunksize * DEV_BSIZE / 1024);
  94                 dm_target_stripe_destroy_config(tsc);
  95                 return EINVAL;
  96         }
  97
  98         /*
  99          * Parse the devices
 100          */
 101
 102         kprintf("dm: Stripe %d devices chunk size %dKB\n",
 103                 (int)tsc->stripe_num,
 104                 (int)tsc->stripe_chunksize
 105         );
 106
 107         for (n = 0; n < tsc->stripe_num; ++n) {
 108                 ap = strsep(&params, " \t");
 109                 if (ap == NULL)
 110                         break;
 111                 tsc->stripe_devs[n].pdev = dm_pdev_insert(ap);
 112                 if (tsc->stripe_devs[n].pdev == NULL)
 113                         break;
 114                 ap = strsep(&params, " \t");
 115                 if (ap == NULL)
 116                         break;
 117                 tsc->stripe_devs[n].offset = atoi64(ap);
 118         }
 119         if (n != tsc->stripe_num) {
 120                 dm_target_stripe_destroy_config(tsc);
 121                 return (ENOENT);
 122         }
 123
 124         *target_config = tsc;
 125
 126         dmv->dev_type = DM_STRIPE_DEV;
 127
 128         return 0;
 129 }
 130
 131 /*
 132  * Status routine called to get params string.
 133  */
 134 static char *
 135 dm_target_stripe_status(void *target_config)
 136 {
 137         dm_target_stripe_config_t *tsc;
 138         char *params;
 139         char *ptr;
 140         size_t len;
 141         size_t nlen;
 142         int n;
 143
 144         tsc = target_config;
 145
 146         /* caller expects use of M_DM for returned params */
 147         nlen = DM_MAX_PARAMS_SIZE;
 148         params = kmalloc(nlen, M_DM, M_WAITOK);
 149         ptr = params;
 150
 151         ksnprintf(ptr, nlen, "%d %jd",
 152                   tsc->stripe_num, (intmax_t)tsc->stripe_chunksize);
 153         len = strlen(params);
 154         ptr += len;
 155         nlen -= len;
 156
 157         for (n = 0; n < tsc->stripe_num; ++n) {
 158                 ksnprintf(ptr, nlen, " %s %jd",
 159                           tsc->stripe_devs[n].pdev->name,
 160                           (intmax_t)tsc->stripe_devs[n].offset);
 161                 len = strlen(ptr);
 162                 ptr += len;
 163                 nlen -= len;
 164         }
 165
 166         return params;
 167 }
 168
 169 /*
 170  * Strategy routine called from dm_strategy.
 171  */
 172 static int
 173 dm_target_stripe_strategy(dm_table_entry_t *table_en, struct buf *bp)
 174 {
 175         dm_target_stripe_config_t *tsc;
 176         struct bio *bio = &bp->b_bio1;
 177         struct buf *nestbuf;
 178         uint64_t blkno, blkoff;
 179         uint64_t stripe, blknr;
 180         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 181         int devnr;
 182
 183         tsc = table_en->target_config;
 184         if (tsc == NULL)
 185                 return 0;
 186
 187         /* calculate extent of request */
 188         KKASSERT(bp->b_resid % DEV_BSIZE == 0);
 189
 190         switch(bp->b_cmd) {
 191         case BUF_CMD_READ:
 192         case BUF_CMD_WRITE:
 193         case BUF_CMD_FREEBLKS:
 194                 /*
 195                  * Loop through to individual operations
 196                  */
 197                 blkno = bp->b_bio1.bio_offset / DEV_BSIZE;
 198                 blkoff = 0;
 199                 num_blks = bp->b_resid / DEV_BSIZE;
 200                 nestiobuf_init(bio);
 201
 202                 while (num_blks > 0) {
 203                         /* blockno to strip piece nr */
 204                         stripe = blkno / tsc->stripe_chunksize;
 205                         stripe_off = blkno % tsc->stripe_chunksize;
 206
 207                         /* where we are inside the strip */
 208                         devnr = stripe % tsc->stripe_num;
 209                         blknr = stripe / tsc->stripe_num;
 210
 211                         /* how much is left before we hit a boundary */
 212                         stripe_rest = tsc->stripe_chunksize - stripe_off;
 213
 214                         /* issue this piece on stripe `stripe' */
 215                         issue_blks = MIN(stripe_rest, num_blks);
 216                         nestbuf = getpbuf(NULL);
 217                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 218
 219                         nestiobuf_add(bio, nestbuf, blkoff,
 220                                         issue_blks * DEV_BSIZE, NULL);
 221
 222                         /* I need number of bytes. */
 223                         nestbuf->b_bio1.bio_offset =
 224                                 blknr * tsc->stripe_chunksize + stripe_off;
 225                         nestbuf->b_bio1.bio_offset +=
 226                                 tsc->stripe_devs[devnr].offset;
 227                         nestbuf->b_bio1.bio_offset *= DEV_BSIZE;
 228
 229                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 230                                     &nestbuf->b_bio1);
 231
 232                         blkno += issue_blks;
 233                         blkoff += issue_blks * DEV_BSIZE;
 234                         num_blks -= issue_blks;
 235                 }
 236                 nestiobuf_start(bio);
 237                 break;
 238         case BUF_CMD_FLUSH:
 239                 nestiobuf_init(bio);
 240                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 241                         nestbuf = getpbuf(NULL);
 242                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 243
 244                         nestiobuf_add(bio, nestbuf, 0, 0, NULL);
 245                         nestbuf->b_bio1.bio_offset = 0;
 246                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 247                                     &nestbuf->b_bio1);
 248                 }
 249                 nestiobuf_start(bio);
 250                 break;
 251         default:
 252                 bp->b_flags |= B_ERROR;
 253                 bp->b_error = EIO;
 254                 biodone(bio);
 255                 break;
 256         }
 257         return 0;
 258 }
 259
 260
 261 static int
 262 dm_target_stripe_dump(dm_table_entry_t *table_en, void *data, size_t length, off_t offset)
 263 {
 264         dm_target_stripe_config_t *tsc;
 265         uint64_t blkno, blkoff;
 266         uint64_t stripe, blknr;
 267         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 268         uint64_t off2, len2;
 269         int devnr;
 270
 271         tsc = table_en->target_config;
 272         if (tsc == NULL)
 273                 return 0;
 274
 275         /* calculate extent of request */
 276         KKASSERT(length % DEV_BSIZE == 0);
 277
 278         blkno = offset / DEV_BSIZE;
 279         blkoff = 0;
 280         num_blks = length / DEV_BSIZE;
 281
 282         /*
 283          * 0 length means flush buffers and return
 284          */
 285         if (length == 0) {
 286                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 287                         if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 288                                 return ENXIO;
 289
 290                         dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 291                             data, 0, offset, 0);
 292                 }
 293                 return 0;
 294         }
 295
 296         while (num_blks > 0) {
 297                 /* blockno to strip piece nr */
 298                 stripe = blkno / tsc->stripe_chunksize;
 299                 stripe_off = blkno % tsc->stripe_chunksize;
 300
 301                 /* where we are inside the strip */
 302                 devnr = stripe % tsc->stripe_num;
 303                 blknr = stripe / tsc->stripe_num;
 304
 305                 /* how much is left before we hit a boundary */
 306                 stripe_rest = tsc->stripe_chunksize - stripe_off;
 307
 308                 /* issue this piece on stripe `stripe' */
 309                 issue_blks = MIN(stripe_rest, num_blks);
 310
 311 #if 0
 312                 nestiobuf_add(bio, nestbuf, blkoff,
 313                                 issue_blks * DEV_BSIZE);
 314 #endif
 315                 len2 = issue_blks * DEV_BSIZE;
 316
 317                 /* I need number of bytes. */
 318                 off2 = blknr * tsc->stripe_chunksize + stripe_off;
 319                 off2 += tsc->stripe_devs[devnr].offset;
 320                 off2 *= DEV_BSIZE;
 321                 off2 = dm_pdev_correct_dump_offset(tsc->stripe_devs[devnr].pdev,
 322                     off2);
 323
 324                 if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 325                         return ENXIO;
 326
 327                 dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 328                     (char *)data + blkoff, 0, off2, len2);
 329
 330                 blkno += issue_blks;
 331                 blkoff += issue_blks * DEV_BSIZE;
 332                 num_blks -= issue_blks;
 333         }
 334
 335         return 0;
 336 }
 337
 338 /*
 339  * Destroy a dm table entry for stripes.
 340  */
 341 static int
 342 dm_target_stripe_destroy(dm_table_entry_t *table_en)
 343 {
 344         dm_target_stripe_config_t *tsc;
 345
 346         if ((tsc = table_en->target_config) != NULL) {
 347                 table_en->target_config = NULL;
 348                 dm_target_stripe_destroy_config(tsc);
 349         }
 350
 351         return 0;
 352 }
 353
 354 static void
 355 dm_target_stripe_destroy_config(dm_target_stripe_config_t *tsc)
 356 {
 357         int n;
 358
 359         for (n = 0; n < tsc->stripe_num; ++n) {
 360                 if (tsc->stripe_devs[n].pdev) {
 361                         dm_pdev_decr(tsc->stripe_devs[n].pdev);
 362                         tsc->stripe_devs[n].pdev = NULL;
 363                 }
 364         }
 365         kfree(tsc, M_DMSTRIPE);
 366 }
 367
 368 /*
 369  * Generate properties from stripe table entry.
 370  */
 371 static int
 372 dm_target_stripe_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
 373 {
 374         dm_target_stripe_config_t *tsc;
 375         struct vattr va;
 376         int error;
 377         int n;
 378
 379         if (table_en->target_config == NULL)
 380                 return ENOENT;
 381
 382         tsc = table_en->target_config;
 383         error = 0;
 384         for (n = 0; n < tsc->stripe_num; ++n) {
 385                 error = VOP_GETATTR(tsc->stripe_devs[n].pdev->pdev_vnode, &va);
 386                 if (error)
 387                         break;
 388                 prop_array_add_uint64(prop_array,
 389                                 (uint64_t)makeudev(va.va_rmajor, va.va_rminor));
 390         }
 391         return (error);
 392 }
 393
 394 /*
 395  * Unsupported for this target.
 396  */
 397 static int
 398 dm_target_stripe_upcall(dm_table_entry_t * table_en, struct buf * bp)
 399 {
 400         return 0;
 401 }
 402
 403 static int
 404 dmts_mod_handler(module_t mod, int type, void *unused)
 405 {
 406         dm_target_t *dmt = NULL;
 407         int err = 0;
 408
 409         switch(type) {
 410         case MOD_LOAD:
 411                 if ((dmt = dm_target_lookup("striped")) != NULL) {
 412                         dm_target_unbusy(dmt);
 413                         return EEXIST;
 414                 }
 415                 dmt = dm_target_alloc("striped");
 416                 dmt->version[0] = 1;
 417                 dmt->version[1] = 0;
 418                 dmt->version[2] = 3;
 419                 strlcpy(dmt->name, "striped", DM_MAX_TYPE_NAME);
 420                 dmt->init = &dm_target_stripe_init;
 421                 dmt->status = &dm_target_stripe_status;
 422                 dmt->strategy = &dm_target_stripe_strategy;
 423                 dmt->deps = &dm_target_stripe_deps;
 424                 dmt->destroy = &dm_target_stripe_destroy;
 425                 dmt->upcall = &dm_target_stripe_upcall;
 426                 dmt->dump = &dm_target_stripe_dump;
 427
 428                 err = dm_target_insert(dmt);
 429                 if (err == 0)
 430                         kprintf("dm_target_stripe: Successfully initialized\n");
 431                 break;
 432
 433         case MOD_UNLOAD:
 434                 err = dm_target_rem("striped");
 435                 if (err == 0)
 436                         kprintf("dm_target_stripe: unloaded\n");
 437                 break;
 438
 439         default:
 440                 break;
 441         }
 442
 443         return err;
 444 }
 445
 446 DM_TARGET_MODULE(dm_target_striped, dmts_mod_handler);