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
  42 #include <sys/buf.h>
  43 #include <sys/malloc.h>
  44 #include <sys/vnode.h>
  45
  46 #include <dev/disk/dm/dm.h>
  47 MALLOC_DEFINE(M_DMSTRIPE, "dm_stripe", "Device Mapper Target Stripe");
  48
  49 #define MAX_STRIPES 32
  50
  51 struct target_stripe_dev {
  52         dm_pdev_t *pdev;
  53         uint64_t offset;
  54 };
  55
  56 typedef struct target_stripe_config {
  57         struct target_stripe_dev stripe_devs[MAX_STRIPES];
  58         int stripe_num;
  59         uint64_t stripe_chunksize;
  60 } dm_target_stripe_config_t;
  61
  62 static void dm_target_stripe_destroy_config(dm_target_stripe_config_t *tsc);
  63
  64 /*
  65  * Init function called from dm_table_load_ioctl.
  66  *
  67  * Example line sent to dm from lvm tools when using striped target.
  68  * start length striped #stripes chunk_size device1 offset1 ... deviceN offsetN
  69  * 0 65536 striped 2 512 /dev/hda 0 /dev/hdb 0
  70  */
  71 static int
  72 dm_target_stripe_init(dm_dev_t *dmv, void **target_config, char *params)
  73 {
  74         dm_target_stripe_config_t *tsc;
  75         int n;
  76         char *ap;
  77
  78         if (params == NULL)
  79                 return EINVAL;
  80
  81         /*
  82          * nstripes
  83          */
  84         ap = strsep(&params, " \t");
  85         if (ap == NULL)
  86                 return EINVAL;
  87         n = (int)atoi64(ap);
  88         if (n < 0 || n > MAX_STRIPES) {
  89                 kprintf("dm: Error %d stripes not supported (%d max)\n",
  90                         n, MAX_STRIPES);
  91                 return ENOTSUP;
  92         }
  93
  94         tsc = kmalloc(sizeof(dm_target_stripe_config_t),
  95                       M_DMSTRIPE, M_WAITOK | M_ZERO);
  96         tsc->stripe_num = n;
  97
  98         ap = strsep(&params, " \t");
  99         if (ap == NULL) {
 100                 dm_target_stripe_destroy_config(tsc);
 101                 return EINVAL;
 102         }
 103         tsc->stripe_chunksize = atoi64(ap);
 104         if (tsc->stripe_chunksize < 1 ||
 105             tsc->stripe_chunksize * DEV_BSIZE > MAXPHYS) {
 106                 kprintf("dm: Error unsupported chunk size %jdKB\n",
 107                         (intmax_t)tsc->stripe_chunksize * DEV_BSIZE / 1024);
 108                 dm_target_stripe_destroy_config(tsc);
 109                 return EINVAL;
 110         }
 111
 112         /*
 113          * Parse the devices
 114          */
 115
 116         kprintf("dm: Stripe %d devices chunk size %dKB\n",
 117                 (int)tsc->stripe_num,
 118                 (int)tsc->stripe_chunksize
 119         );
 120
 121         for (n = 0; n < tsc->stripe_num; ++n) {
 122                 ap = strsep(&params, " \t");
 123                 if (ap == NULL)
 124                         break;
 125                 tsc->stripe_devs[n].pdev = dm_pdev_insert(ap);
 126                 if (tsc->stripe_devs[n].pdev == NULL)
 127                         break;
 128                 ap = strsep(&params, " \t");
 129                 if (ap == NULL)
 130                         break;
 131                 tsc->stripe_devs[n].offset = atoi64(ap);
 132         }
 133         if (n != tsc->stripe_num) {
 134                 dm_target_stripe_destroy_config(tsc);
 135                 return (ENOENT);
 136         }
 137
 138         *target_config = tsc;
 139
 140         dmv->dev_type = DM_STRIPE_DEV;
 141
 142         return 0;
 143 }
 144
 145 /*
 146  * Status routine called to get params string.
 147  */
 148 static char *
 149 dm_target_stripe_status(void *target_config)
 150 {
 151         dm_target_stripe_config_t *tsc;
 152         char *params;
 153         char *ptr;
 154         size_t len;
 155         size_t nlen;
 156         int n;
 157
 158         tsc = target_config;
 159
 160         /* caller expects use of M_DM for returned params */
 161         nlen = DM_MAX_PARAMS_SIZE;
 162         params = kmalloc(nlen, M_DM, M_WAITOK);
 163         ptr = params;
 164
 165         ksnprintf(ptr, nlen, "%d %jd",
 166                   tsc->stripe_num, (intmax_t)tsc->stripe_chunksize);
 167         len = strlen(params);
 168         ptr += len;
 169         nlen -= len;
 170
 171         for (n = 0; n < tsc->stripe_num; ++n) {
 172                 ksnprintf(ptr, nlen, " %s %jd",
 173                           tsc->stripe_devs[n].pdev->name,
 174                           (intmax_t)tsc->stripe_devs[n].offset);
 175                 len = strlen(ptr);
 176                 ptr += len;
 177                 nlen -= len;
 178         }
 179
 180         return params;
 181 }
 182
 183 /*
 184  * Strategy routine called from dm_strategy.
 185  */
 186 static int
 187 dm_target_stripe_strategy(dm_table_entry_t *table_en, struct buf *bp)
 188 {
 189         dm_target_stripe_config_t *tsc;
 190         struct bio *bio = &bp->b_bio1;
 191         struct buf *nestbuf;
 192         uint64_t blkno, blkoff;
 193         uint64_t stripe, blknr;
 194         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 195         int devnr;
 196
 197         tsc = table_en->target_config;
 198         if (tsc == NULL)
 199                 return 0;
 200
 201         /* calculate extent of request */
 202         KKASSERT(bp->b_resid % DEV_BSIZE == 0);
 203
 204         switch(bp->b_cmd) {
 205         case BUF_CMD_READ:
 206         case BUF_CMD_WRITE:
 207         case BUF_CMD_FREEBLKS:
 208                 /*
 209                  * Loop through to individual operations
 210                  */
 211                 blkno = bp->b_bio1.bio_offset / DEV_BSIZE;
 212                 blkoff = 0;
 213                 num_blks = bp->b_resid / DEV_BSIZE;
 214                 nestiobuf_init(bio);
 215
 216                 while (num_blks > 0) {
 217                         /* blockno to strip piece nr */
 218                         stripe = blkno / tsc->stripe_chunksize;
 219                         stripe_off = blkno % tsc->stripe_chunksize;
 220
 221                         /* where we are inside the strip */
 222                         devnr = stripe % tsc->stripe_num;
 223                         blknr = stripe / tsc->stripe_num;
 224
 225                         /* how much is left before we hit a boundary */
 226                         stripe_rest = tsc->stripe_chunksize - stripe_off;
 227
 228                         /* issue this piece on stripe `stripe' */
 229                         issue_blks = MIN(stripe_rest, num_blks);
 230                         nestbuf = getpbuf(NULL);
 231                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 232
 233                         nestiobuf_add(bio, nestbuf, blkoff,
 234                                         issue_blks * DEV_BSIZE, NULL);
 235
 236                         /* I need number of bytes. */
 237                         nestbuf->b_bio1.bio_offset =
 238                                 blknr * tsc->stripe_chunksize + stripe_off;
 239                         nestbuf->b_bio1.bio_offset +=
 240                                 tsc->stripe_devs[devnr].offset;
 241                         nestbuf->b_bio1.bio_offset *= DEV_BSIZE;
 242
 243                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 244                                     &nestbuf->b_bio1);
 245
 246                         blkno += issue_blks;
 247                         blkoff += issue_blks * DEV_BSIZE;
 248                         num_blks -= issue_blks;
 249                 }
 250                 nestiobuf_start(bio);
 251                 break;
 252         case BUF_CMD_FLUSH:
 253                 nestiobuf_init(bio);
 254                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 255                         nestbuf = getpbuf(NULL);
 256                         nestbuf->b_flags |= bio->bio_buf->b_flags & B_HASBOGUS;
 257
 258                         nestiobuf_add(bio, nestbuf, 0, 0, NULL);
 259                         nestbuf->b_bio1.bio_offset = 0;
 260                         vn_strategy(tsc->stripe_devs[devnr].pdev->pdev_vnode,
 261                                     &nestbuf->b_bio1);
 262                 }
 263                 nestiobuf_start(bio);
 264                 break;
 265         default:
 266                 bp->b_flags |= B_ERROR;
 267                 bp->b_error = EIO;
 268                 biodone(bio);
 269                 break;
 270         }
 271         return 0;
 272 }
 273
 274
 275 static int
 276 dm_target_stripe_dump(dm_table_entry_t *table_en, void *data, size_t length, off_t offset)
 277 {
 278         dm_target_stripe_config_t *tsc;
 279         uint64_t blkno, blkoff;
 280         uint64_t stripe, blknr;
 281         uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
 282         uint64_t off2, len2;
 283         int devnr;
 284
 285         tsc = table_en->target_config;
 286         if (tsc == NULL)
 287                 return 0;
 288
 289         /* calculate extent of request */
 290         KKASSERT(length % DEV_BSIZE == 0);
 291
 292         blkno = offset / DEV_BSIZE;
 293         blkoff = 0;
 294         num_blks = length / DEV_BSIZE;
 295
 296         /*
 297          * 0 length means flush buffers and return
 298          */
 299         if (length == 0) {
 300                 for (devnr = 0; devnr < tsc->stripe_num; ++devnr) {
 301                         if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 302                                 return ENXIO;
 303
 304                         dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 305                             data, 0, offset, 0);
 306                 }
 307                 return 0;
 308         }
 309
 310         while (num_blks > 0) {
 311                 /* blockno to strip piece nr */
 312                 stripe = blkno / tsc->stripe_chunksize;
 313                 stripe_off = blkno % tsc->stripe_chunksize;
 314
 315                 /* where we are inside the strip */
 316                 devnr = stripe % tsc->stripe_num;
 317                 blknr = stripe / tsc->stripe_num;
 318
 319                 /* how much is left before we hit a boundary */
 320                 stripe_rest = tsc->stripe_chunksize - stripe_off;
 321
 322                 /* issue this piece on stripe `stripe' */
 323                 issue_blks = MIN(stripe_rest, num_blks);
 324
 325 #if 0
 326                 nestiobuf_add(bio, nestbuf, blkoff,
 327                                 issue_blks * DEV_BSIZE);
 328 #endif
 329                 len2 = issue_blks * DEV_BSIZE;
 330
 331                 /* I need number of bytes. */
 332                 off2 = blknr * tsc->stripe_chunksize + stripe_off;
 333                 off2 += tsc->stripe_devs[devnr].offset;
 334                 off2 *= DEV_BSIZE;
 335                 off2 = dm_pdev_correct_dump_offset(tsc->stripe_devs[devnr].pdev,
 336                     off2);
 337
 338                 if (tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev == NULL)
 339                         return ENXIO;
 340
 341                 dev_ddump(tsc->stripe_devs[devnr].pdev->pdev_vnode->v_rdev,
 342                     (char *)data + blkoff, 0, off2, len2);
 343
 344                 blkno += issue_blks;
 345                 blkoff += issue_blks * DEV_BSIZE;
 346                 num_blks -= issue_blks;
 347         }
 348
 349         return 0;
 350 }
 351
 352 /*
 353  * Destroy a dm table entry for stripes.
 354  */
 355 static int
 356 dm_target_stripe_destroy(dm_table_entry_t *table_en)
 357 {
 358         dm_target_stripe_config_t *tsc;
 359
 360         if ((tsc = table_en->target_config) != NULL) {
 361                 table_en->target_config = NULL;
 362                 dm_target_stripe_destroy_config(tsc);
 363         }
 364
 365         return 0;
 366 }
 367
 368 static void
 369 dm_target_stripe_destroy_config(dm_target_stripe_config_t *tsc)
 370 {
 371         int n;
 372
 373         for (n = 0; n < tsc->stripe_num; ++n) {
 374                 if (tsc->stripe_devs[n].pdev) {
 375                         dm_pdev_decr(tsc->stripe_devs[n].pdev);
 376                         tsc->stripe_devs[n].pdev = NULL;
 377                 }
 378         }
 379         kfree(tsc, M_DMSTRIPE);
 380 }
 381
 382 /*
 383  * Generate properties from stripe table entry.
 384  */
 385 static int
 386 dm_target_stripe_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
 387 {
 388         dm_target_stripe_config_t *tsc;
 389         struct vattr va;
 390         int error;
 391         int n;
 392
 393         if (table_en->target_config == NULL)
 394                 return ENOENT;
 395
 396         tsc = table_en->target_config;
 397         error = 0;
 398         for (n = 0; n < tsc->stripe_num; ++n) {
 399                 error = VOP_GETATTR(tsc->stripe_devs[n].pdev->pdev_vnode, &va);
 400                 if (error)
 401                         break;
 402                 prop_array_add_uint64(prop_array,
 403                                 (uint64_t)makeudev(va.va_rmajor, va.va_rminor));
 404         }
 405         return (error);
 406 }
 407
 408 /*
 409  * Unsupported for this target.
 410  */
 411 static int
 412 dm_target_stripe_upcall(dm_table_entry_t *table_en, struct buf *bp)
 413 {
 414         return 0;
 415 }
 416
 417 static int
 418 dmts_mod_handler(module_t mod, int type, void *unused)
 419 {
 420         dm_target_t *dmt = NULL;
 421         int err = 0;
 422
 423         switch(type) {
 424         case MOD_LOAD:
 425                 if ((dmt = dm_target_lookup("striped")) != NULL) {
 426                         dm_target_unbusy(dmt);
 427                         return EEXIST;
 428                 }
 429                 dmt = dm_target_alloc("striped");
 430                 dmt->version[0] = 1;
 431                 dmt->version[1] = 0;
 432                 dmt->version[2] = 3;
 433                 strlcpy(dmt->name, "striped", DM_MAX_TYPE_NAME);
 434                 dmt->init = &dm_target_stripe_init;
 435                 dmt->status = &dm_target_stripe_status;
 436                 dmt->strategy = &dm_target_stripe_strategy;
 437                 dmt->deps = &dm_target_stripe_deps;
 438                 dmt->destroy = &dm_target_stripe_destroy;
 439                 dmt->upcall = &dm_target_stripe_upcall;
 440                 dmt->dump = &dm_target_stripe_dump;
 441
 442                 err = dm_target_insert(dmt);
 443                 if (err == 0)
 444                         kprintf("dm_target_stripe: Successfully initialized\n");
 445                 break;
 446
 447         case MOD_UNLOAD:
 448                 err = dm_target_rem("striped");
 449                 if (err == 0)
 450                         kprintf("dm_target_stripe: unloaded\n");
 451                 break;
 452
 453         default:
 454                 break;
 455         }
 456
 457         return err;
 458 }
 459
 460 DM_TARGET_MODULE(dm_target_striped, dmts_mod_handler);