lwext4/ext4_blockdev.c

   1 /*
   2  * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup lwext4
  30  * @{
  31  */
  32 /**
  33  * @file  ext4_blockdev.c
  34  * @brief Block device module.
  35  */
  36
  37 #include "ext4_config.h"
  38 #include "ext4_blockdev.h"
  39 #include "ext4_errno.h"
  40 #include "ext4_debug.h"
  41
  42 #include <string.h>
  43 #include <stdlib.h>
  44
  45 static void ext4_bdif_lock(struct ext4_blockdev *bdev)
  46 {
  47         if (!bdev->bdif->lock)
  48                 return;
  49
  50         int r = bdev->bdif->lock(bdev);
  51         ext4_assert(r == EOK);
  52 }
  53
  54 static void ext4_bdif_unlock(struct ext4_blockdev *bdev)
  55 {
  56         if (!bdev->bdif->unlock)
  57                 return;
  58
  59         int r = bdev->bdif->unlock(bdev);
  60         ext4_assert(r == EOK);
  61 }
  62
  63 static int ext4_bdif_bread(struct ext4_blockdev *bdev, void *buf,
  64                            uint64_t blk_id, uint32_t blk_cnt)
  65 {
  66         ext4_bdif_lock(bdev);
  67         int r = bdev->bdif->bread(bdev, buf, blk_id, blk_cnt);
  68         bdev->bdif->bread_ctr++;
  69         ext4_bdif_unlock(bdev);
  70         return r;
  71 }
  72
  73 static int ext4_bdif_bwrite(struct ext4_blockdev *bdev, const void *buf,
  74                             uint64_t blk_id, uint32_t blk_cnt)
  75 {
  76         ext4_bdif_lock(bdev);
  77         int r = bdev->bdif->bwrite(bdev, buf, blk_id, blk_cnt);
  78         bdev->bdif->bwrite_ctr++;
  79         ext4_bdif_unlock(bdev);
  80         return r;
  81 }
  82
  83 int ext4_block_init(struct ext4_blockdev *bdev)
  84 {
  85         int rc;
  86         ext4_assert(bdev);
  87         ext4_assert(bdev->bdif);
  88         ext4_assert(bdev->bdif->open &&
  89                    bdev->bdif->close &&
  90                    bdev->bdif->bread &&
  91                    bdev->bdif->bwrite);
  92
  93         if (bdev->bdif->ph_refctr) {
  94                 bdev->bdif->ph_refctr++;
  95                 return EOK;
  96         }
  97
  98         /*Low level block init*/
  99         rc = bdev->bdif->open(bdev);
 100         if (rc != EOK)
 101                 return rc;
 102
 103         bdev->bdif->ph_refctr = 1;
 104         return EOK;
 105 }
 106
 107 int ext4_block_bind_bcache(struct ext4_blockdev *bdev, struct ext4_bcache *bc)
 108 {
 109         ext4_assert(bdev && bc);
 110         bdev->bc = bc;
 111         bc->bdev = bdev;
 112         return EOK;
 113 }
 114
 115 void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint64_t lb_bsize)
 116 {
 117         /*Logical block size has to be multiply of physical */
 118         ext4_assert(!(lb_bsize % bdev->bdif->ph_bsize));
 119
 120         bdev->lg_bsize = lb_bsize;
 121         bdev->lg_bcnt = bdev->part_size / lb_bsize;
 122 }
 123
 124 int ext4_block_fini(struct ext4_blockdev *bdev)
 125 {
 126         ext4_assert(bdev);
 127
 128         if (!bdev->bdif->ph_refctr)
 129                 return EOK;
 130
 131         bdev->bdif->ph_refctr--;
 132         if (bdev->bdif->ph_refctr)
 133                 return EOK;
 134
 135         /*Low level block fini*/
 136         return bdev->bdif->close(bdev);
 137 }
 138
 139 int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf)
 140 {
 141         int r;
 142         struct ext4_bcache *bc = bdev->bc;
 143
 144         if (ext4_bcache_test_flag(buf, BC_DIRTY) &&
 145             ext4_bcache_test_flag(buf, BC_UPTODATE)) {
 146                 r = ext4_blocks_set_direct(bdev, buf->data, buf->lba, 1);
 147                 if (r) {
 148                         if (buf->end_write) {
 149                                 bc->dont_shake = true;
 150                                 buf->end_write(bc, buf, r, buf->end_write_arg);
 151                                 bc->dont_shake = false;
 152                         }
 153
 154                         return r;
 155                 }
 156
 157                 ext4_bcache_remove_dirty_node(bc, buf);
 158                 ext4_bcache_clear_flag(buf, BC_DIRTY);
 159                 if (buf->end_write) {
 160                         bc->dont_shake = true;
 161                         buf->end_write(bc, buf, r, buf->end_write_arg);
 162                         bc->dont_shake = false;
 163                 }
 164         }
 165         return EOK;
 166 }
 167
 168 int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba)
 169 {
 170         int r = EOK;
 171         struct ext4_buf *buf;
 172         struct ext4_block b;
 173         buf = ext4_bcache_find_get(bdev->bc, &b, lba);
 174         if (buf) {
 175                 r = ext4_block_flush_buf(bdev, buf);
 176                 ext4_bcache_free(bdev->bc, &b);
 177         }
 178         return r;
 179 }
 180
 181 int ext4_block_cache_shake(struct ext4_blockdev *bdev)
 182 {
 183         int r = EOK;
 184         struct ext4_buf *buf;
 185         if (bdev->bc->dont_shake)
 186                 return EOK;
 187
 188         while (!RB_EMPTY(&bdev->bc->lru_root) &&
 189                 ext4_bcache_is_full(bdev->bc)) {
 190
 191                 buf = ext4_buf_lowest_lru(bdev->bc);
 192                 ext4_assert(buf);
 193                 if (ext4_bcache_test_flag(buf, BC_DIRTY)) {
 194                         r = ext4_block_flush_buf(bdev, buf);
 195                         if (r != EOK)
 196                                 break;
 197
 198                 }
 199
 200                 ext4_bcache_drop_buf(bdev->bc, buf);
 201         }
 202         return r;
 203 }
 204
 205 int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
 206                           uint64_t lba)
 207 {
 208         bool is_new;
 209         int r;
 210
 211         ext4_assert(bdev && b);
 212
 213         if (!bdev->bdif->ph_refctr)
 214                 return EIO;
 215
 216         if (!(lba < bdev->lg_bcnt))
 217                 return ERANGE;
 218
 219         b->lb_id = lba;
 220
 221         /*If cache is full we have to (flush and) drop it anyway :(*/
 222         r = ext4_block_cache_shake(bdev);
 223         if (r != EOK)
 224                 return r;
 225
 226         r = ext4_bcache_alloc(bdev->bc, b, &is_new);
 227         if (r != EOK)
 228                 return r;
 229
 230         if (!b->data)
 231                 return ENOMEM;
 232
 233         return EOK;
 234 }
 235
 236 int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
 237                    uint64_t lba)
 238 {
 239         int r = ext4_block_get_noread(bdev, b, lba);
 240         if (r != EOK)
 241                 return r;
 242
 243         if (ext4_bcache_test_flag(b->buf, BC_UPTODATE)) {
 244                 /* Data in the cache is up-to-date.
 245                  * Reading from physical device is not required */
 246                 return EOK;
 247         }
 248
 249         r = ext4_blocks_get_direct(bdev, b->data, lba, 1);
 250         if (r != EOK) {
 251                 ext4_bcache_free(bdev->bc, b);
 252                 b->lb_id = 0;
 253                 return r;
 254         }
 255
 256         /* Mark buffer up-to-date, since
 257          * fresh data is read from physical device just now. */
 258         ext4_bcache_set_flag(b->buf, BC_UPTODATE);
 259         return EOK;
 260 }
 261
 262 int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b)
 263 {
 264         ext4_assert(bdev && b);
 265         ext4_assert(b->buf);
 266
 267         if (!bdev->bdif->ph_refctr)
 268                 return EIO;
 269
 270         return ext4_bcache_free(bdev->bc, b);
 271 }
 272
 273 int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
 274                            uint32_t cnt)
 275 {
 276         uint64_t pba;
 277         uint32_t pb_cnt;
 278
 279         ext4_assert(bdev && buf);
 280
 281         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 282         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 283
 284         return ext4_bdif_bread(bdev, buf, pba, pb_cnt * cnt);
 285 }
 286
 287 int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
 288                            uint64_t lba, uint32_t cnt)
 289 {
 290         uint64_t pba;
 291         uint32_t pb_cnt;
 292
 293         ext4_assert(bdev && buf);
 294
 295         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 296         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 297
 298         return ext4_bdif_bwrite(bdev, buf, pba, pb_cnt * cnt);
 299 }
 300
 301 int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
 302                           const void *buf, uint32_t len)
 303 {
 304         uint64_t block_idx;
 305         uint32_t blen;
 306         uint32_t unalg;
 307         int r = EOK;
 308
 309         const uint8_t *p = (void *)buf;
 310
 311         ext4_assert(bdev && buf);
 312
 313         if (!bdev->bdif->ph_refctr)
 314                 return EIO;
 315
 316         if (off + len > bdev->part_size)
 317                 return EINVAL; /*Ups. Out of range operation*/
 318
 319         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 320
 321         /*OK lets deal with the first possible unaligned block*/
 322         unalg = (off & (bdev->bdif->ph_bsize - 1));
 323         if (unalg) {
 324
 325                 uint32_t wlen = (bdev->bdif->ph_bsize - unalg) > len
 326                                     ? len
 327                                     : (bdev->bdif->ph_bsize - unalg);
 328
 329                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 330                 if (r != EOK)
 331                         return r;
 332
 333                 memcpy(bdev->bdif->ph_bbuf + unalg, p, wlen);
 334                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 335                 if (r != EOK)
 336                         return r;
 337
 338                 p += wlen;
 339                 len -= wlen;
 340                 block_idx++;
 341         }
 342
 343         /*Aligned data*/
 344         blen = len / bdev->bdif->ph_bsize;
 345         r = ext4_bdif_bwrite(bdev, p, block_idx, blen);
 346         if (r != EOK)
 347                 return r;
 348
 349         p += bdev->bdif->ph_bsize * blen;
 350         len -= bdev->bdif->ph_bsize * blen;
 351
 352         block_idx += blen;
 353
 354         /*Rest of the data*/
 355         if (len) {
 356                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 357                 if (r != EOK)
 358                         return r;
 359
 360                 memcpy(bdev->bdif->ph_bbuf, p, len);
 361                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 362                 if (r != EOK)
 363                         return r;
 364         }
 365
 366         return r;
 367 }
 368
 369 int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
 370                          uint32_t len)
 371 {
 372         uint64_t block_idx;
 373         uint32_t blen;
 374         uint32_t unalg;
 375         int r = EOK;
 376
 377         uint8_t *p = (void *)buf;
 378
 379         ext4_assert(bdev && buf);
 380
 381         if (!bdev->bdif->ph_refctr)
 382                 return EIO;
 383
 384         if (off + len > bdev->part_size)
 385                 return EINVAL; /*Ups. Out of range operation*/
 386
 387         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 388
 389         /*OK lets deal with the first possible unaligned block*/
 390         unalg = (off & (bdev->bdif->ph_bsize - 1));
 391         if (unalg) {
 392
 393                 uint32_t rlen = (bdev->bdif->ph_bsize - unalg) > len
 394                                     ? len
 395                                     : (bdev->bdif->ph_bsize - unalg);
 396
 397                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 398                 if (r != EOK)
 399                         return r;
 400
 401                 memcpy(p, bdev->bdif->ph_bbuf + unalg, rlen);
 402
 403                 p += rlen;
 404                 len -= rlen;
 405                 block_idx++;
 406         }
 407
 408         /*Aligned data*/
 409         blen = len / bdev->bdif->ph_bsize;
 410
 411         r = ext4_bdif_bread(bdev, p, block_idx, blen);
 412         if (r != EOK)
 413                 return r;
 414
 415         p += bdev->bdif->ph_bsize * blen;
 416         len -= bdev->bdif->ph_bsize * blen;
 417
 418         block_idx += blen;
 419
 420         /*Rest of the data*/
 421         if (len) {
 422                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 423                 if (r != EOK)
 424                         return r;
 425
 426                 memcpy(p, bdev->bdif->ph_bbuf, len);
 427         }
 428
 429         return r;
 430 }
 431
 432 int ext4_block_cache_flush(struct ext4_blockdev *bdev)
 433 {
 434         while (!SLIST_EMPTY(&bdev->bc->dirty_list)) {
 435                 int r;
 436                 struct ext4_buf *buf = SLIST_FIRST(&bdev->bc->dirty_list);
 437                 ext4_assert(buf);
 438                 r = ext4_block_flush_buf(bdev, buf);
 439                 if (r != EOK)
 440                         return r;
 441
 442         }
 443         return EOK;
 444 }
 445
 446 int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off)
 447 {
 448         if (on_off)
 449                 bdev->cache_write_back++;
 450
 451         if (!on_off && bdev->cache_write_back)
 452                 bdev->cache_write_back--;
 453
 454         if (bdev->cache_write_back)
 455                 return EOK;
 456
 457         /*Flush data in all delayed cache blocks*/
 458         return ext4_block_cache_flush(bdev);
 459 }
 460
 461 /**
 462  * @}
 463  */