src/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_types.h"
  39 #include "ext4_misc.h"
  40 #include "ext4_errno.h"
  41 #include "ext4_debug.h"
  42
  43 #include "ext4_blockdev.h"
  44
  45 #include <string.h>
  46 #include <stdlib.h>
  47
  48 static void ext4_bdif_lock(struct ext4_blockdev *bdev)
  49 {
  50         if (!bdev->bdif->lock)
  51                 return;
  52
  53         int r = bdev->bdif->lock(bdev);
  54         ext4_assert(r == EOK);
  55 }
  56
  57 static void ext4_bdif_unlock(struct ext4_blockdev *bdev)
  58 {
  59         if (!bdev->bdif->unlock)
  60                 return;
  61
  62         int r = bdev->bdif->unlock(bdev);
  63         ext4_assert(r == EOK);
  64 }
  65
  66 static int ext4_bdif_bread(struct ext4_blockdev *bdev, void *buf,
  67                            uint64_t blk_id, uint32_t blk_cnt)
  68 {
  69         ext4_bdif_lock(bdev);
  70         int r = bdev->bdif->bread(bdev, buf, blk_id, blk_cnt);
  71         bdev->bdif->bread_ctr++;
  72         ext4_bdif_unlock(bdev);
  73         return r;
  74 }
  75
  76 static int ext4_bdif_bwrite(struct ext4_blockdev *bdev, const void *buf,
  77                             uint64_t blk_id, uint32_t blk_cnt)
  78 {
  79         ext4_bdif_lock(bdev);
  80         int r = bdev->bdif->bwrite(bdev, buf, blk_id, blk_cnt);
  81         bdev->bdif->bwrite_ctr++;
  82         ext4_bdif_unlock(bdev);
  83         return r;
  84 }
  85
  86 int ext4_block_init(struct ext4_blockdev *bdev)
  87 {
  88         int rc;
  89         ext4_assert(bdev);
  90         ext4_assert(bdev->bdif);
  91         ext4_assert(bdev->bdif->open &&
  92                    bdev->bdif->close &&
  93                    bdev->bdif->bread &&
  94                    bdev->bdif->bwrite);
  95
  96         if (bdev->bdif->ph_refctr) {
  97                 bdev->bdif->ph_refctr++;
  98                 return EOK;
  99         }
 100
 101         /*Low level block init*/
 102         rc = bdev->bdif->open(bdev);
 103         if (rc != EOK)
 104                 return rc;
 105
 106         bdev->bdif->ph_refctr = 1;
 107         return EOK;
 108 }
 109
 110 int ext4_block_bind_bcache(struct ext4_blockdev *bdev, struct ext4_bcache *bc)
 111 {
 112         ext4_assert(bdev && bc);
 113         bdev->bc = bc;
 114         bc->bdev = bdev;
 115         return EOK;
 116 }
 117
 118 void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint32_t lb_bsize)
 119 {
 120         /*Logical block size has to be multiply of physical */
 121         ext4_assert(!(lb_bsize % bdev->bdif->ph_bsize));
 122
 123         bdev->lg_bsize = lb_bsize;
 124         bdev->lg_bcnt = bdev->part_size / lb_bsize;
 125 }
 126
 127 int ext4_block_fini(struct ext4_blockdev *bdev)
 128 {
 129         ext4_assert(bdev);
 130
 131         if (!bdev->bdif->ph_refctr)
 132                 return EOK;
 133
 134         bdev->bdif->ph_refctr--;
 135         if (bdev->bdif->ph_refctr)
 136                 return EOK;
 137
 138         /*Low level block fini*/
 139         return bdev->bdif->close(bdev);
 140 }
 141
 142 int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf)
 143 {
 144         int r;
 145         struct ext4_bcache *bc = bdev->bc;
 146
 147         if (ext4_bcache_test_flag(buf, BC_DIRTY) &&
 148             ext4_bcache_test_flag(buf, BC_UPTODATE)) {
 149                 r = ext4_blocks_set_direct(bdev, buf->data, buf->lba, 1);
 150                 if (r) {
 151                         if (buf->end_write) {
 152                                 bc->dont_shake = true;
 153                                 buf->end_write(bc, buf, r, buf->end_write_arg);
 154                                 bc->dont_shake = false;
 155                         }
 156
 157                         return r;
 158                 }
 159
 160                 ext4_bcache_remove_dirty_node(bc, buf);
 161                 ext4_bcache_clear_flag(buf, BC_DIRTY);
 162                 if (buf->end_write) {
 163                         bc->dont_shake = true;
 164                         buf->end_write(bc, buf, r, buf->end_write_arg);
 165                         bc->dont_shake = false;
 166                 }
 167         }
 168         return EOK;
 169 }
 170
 171 int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba)
 172 {
 173         int r = EOK;
 174         struct ext4_buf *buf;
 175         struct ext4_block b;
 176         buf = ext4_bcache_find_get(bdev->bc, &b, lba);
 177         if (buf) {
 178                 r = ext4_block_flush_buf(bdev, buf);
 179                 ext4_bcache_free(bdev->bc, &b);
 180         }
 181         return r;
 182 }
 183
 184 int ext4_block_cache_shake(struct ext4_blockdev *bdev)
 185 {
 186         int r = EOK;
 187         struct ext4_buf *buf;
 188         if (bdev->bc->dont_shake)
 189                 return EOK;
 190
 191         while (!RB_EMPTY(&bdev->bc->lru_root) &&
 192                 ext4_bcache_is_full(bdev->bc)) {
 193
 194                 buf = ext4_buf_lowest_lru(bdev->bc);
 195                 ext4_assert(buf);
 196                 if (ext4_bcache_test_flag(buf, BC_DIRTY)) {
 197                         r = ext4_block_flush_buf(bdev, buf);
 198                         if (r != EOK)
 199                                 break;
 200
 201                 }
 202
 203                 ext4_bcache_drop_buf(bdev->bc, buf);
 204         }
 205         return r;
 206 }
 207
 208 int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
 209                           uint64_t lba)
 210 {
 211         bool is_new;
 212         int r;
 213
 214         ext4_assert(bdev && b);
 215
 216         if (!bdev->bdif->ph_refctr)
 217                 return EIO;
 218
 219         if (!(lba < bdev->lg_bcnt))
 220                 return ENXIO;
 221
 222         b->lb_id = lba;
 223
 224         /*If cache is full we have to (flush and) drop it anyway :(*/
 225         r = ext4_block_cache_shake(bdev);
 226         if (r != EOK)
 227                 return r;
 228
 229         r = ext4_bcache_alloc(bdev->bc, b, &is_new);
 230         if (r != EOK)
 231                 return r;
 232
 233         if (!b->data)
 234                 return ENOMEM;
 235
 236         return EOK;
 237 }
 238
 239 int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
 240                    uint64_t lba)
 241 {
 242         int r = ext4_block_get_noread(bdev, b, lba);
 243         if (r != EOK)
 244                 return r;
 245
 246         if (ext4_bcache_test_flag(b->buf, BC_UPTODATE)) {
 247                 /* Data in the cache is up-to-date.
 248                  * Reading from physical device is not required */
 249                 return EOK;
 250         }
 251
 252         r = ext4_blocks_get_direct(bdev, b->data, lba, 1);
 253         if (r != EOK) {
 254                 ext4_bcache_free(bdev->bc, b);
 255                 b->lb_id = 0;
 256                 return r;
 257         }
 258
 259         /* Mark buffer up-to-date, since
 260          * fresh data is read from physical device just now. */
 261         ext4_bcache_set_flag(b->buf, BC_UPTODATE);
 262         return EOK;
 263 }
 264
 265 int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b)
 266 {
 267         ext4_assert(bdev && b);
 268         ext4_assert(b->buf);
 269
 270         if (!bdev->bdif->ph_refctr)
 271                 return EIO;
 272
 273         return ext4_bcache_free(bdev->bc, b);
 274 }
 275
 276 int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
 277                            uint32_t cnt)
 278 {
 279         uint64_t pba;
 280         uint32_t pb_cnt;
 281
 282         ext4_assert(bdev && buf);
 283
 284         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 285         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 286
 287         return ext4_bdif_bread(bdev, buf, pba, pb_cnt * cnt);
 288 }
 289
 290 int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
 291                            uint64_t lba, uint32_t cnt)
 292 {
 293         uint64_t pba;
 294         uint32_t pb_cnt;
 295
 296         ext4_assert(bdev && buf);
 297
 298         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 299         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 300
 301         return ext4_bdif_bwrite(bdev, buf, pba, pb_cnt * cnt);
 302 }
 303
 304 int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
 305                           const void *buf, uint32_t len)
 306 {
 307         uint64_t block_idx;
 308         uint32_t blen;
 309         uint32_t unalg;
 310         int r = EOK;
 311
 312         const uint8_t *p = (void *)buf;
 313
 314         ext4_assert(bdev && buf);
 315
 316         if (!bdev->bdif->ph_refctr)
 317                 return EIO;
 318
 319         if (off + len > bdev->part_size)
 320                 return EINVAL; /*Ups. Out of range operation*/
 321
 322         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 323
 324         /*OK lets deal with the first possible unaligned block*/
 325         unalg = (off & (bdev->bdif->ph_bsize - 1));
 326         if (unalg) {
 327
 328                 uint32_t wlen = (bdev->bdif->ph_bsize - unalg) > len
 329                                     ? len
 330                                     : (bdev->bdif->ph_bsize - unalg);
 331
 332                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 333                 if (r != EOK)
 334                         return r;
 335
 336                 memcpy(bdev->bdif->ph_bbuf + unalg, p, wlen);
 337                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 338                 if (r != EOK)
 339                         return r;
 340
 341                 p += wlen;
 342                 len -= wlen;
 343                 block_idx++;
 344         }
 345
 346         /*Aligned data*/
 347         blen = len / bdev->bdif->ph_bsize;
 348         r = ext4_bdif_bwrite(bdev, p, block_idx, blen);
 349         if (r != EOK)
 350                 return r;
 351
 352         p += bdev->bdif->ph_bsize * blen;
 353         len -= bdev->bdif->ph_bsize * blen;
 354
 355         block_idx += blen;
 356
 357         /*Rest of the data*/
 358         if (len) {
 359                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 360                 if (r != EOK)
 361                         return r;
 362
 363                 memcpy(bdev->bdif->ph_bbuf, p, len);
 364                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 365                 if (r != EOK)
 366                         return r;
 367         }
 368
 369         return r;
 370 }
 371
 372 int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
 373                          uint32_t len)
 374 {
 375         uint64_t block_idx;
 376         uint32_t blen;
 377         uint32_t unalg;
 378         int r = EOK;
 379
 380         uint8_t *p = (void *)buf;
 381
 382         ext4_assert(bdev && buf);
 383
 384         if (!bdev->bdif->ph_refctr)
 385                 return EIO;
 386
 387         if (off + len > bdev->part_size)
 388                 return EINVAL; /*Ups. Out of range operation*/
 389
 390         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 391
 392         /*OK lets deal with the first possible unaligned block*/
 393         unalg = (off & (bdev->bdif->ph_bsize - 1));
 394         if (unalg) {
 395
 396                 uint32_t rlen = (bdev->bdif->ph_bsize - unalg) > len
 397                                     ? len
 398                                     : (bdev->bdif->ph_bsize - unalg);
 399
 400                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 401                 if (r != EOK)
 402                         return r;
 403
 404                 memcpy(p, bdev->bdif->ph_bbuf + unalg, rlen);
 405
 406                 p += rlen;
 407                 len -= rlen;
 408                 block_idx++;
 409         }
 410
 411         /*Aligned data*/
 412         blen = len / bdev->bdif->ph_bsize;
 413
 414         r = ext4_bdif_bread(bdev, p, block_idx, blen);
 415         if (r != EOK)
 416                 return r;
 417
 418         p += bdev->bdif->ph_bsize * blen;
 419         len -= bdev->bdif->ph_bsize * blen;
 420
 421         block_idx += blen;
 422
 423         /*Rest of the data*/
 424         if (len) {
 425                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 426                 if (r != EOK)
 427                         return r;
 428
 429                 memcpy(p, bdev->bdif->ph_bbuf, len);
 430         }
 431
 432         return r;
 433 }
 434
 435 int ext4_block_cache_flush(struct ext4_blockdev *bdev)
 436 {
 437         while (!SLIST_EMPTY(&bdev->bc->dirty_list)) {
 438                 int r;
 439                 struct ext4_buf *buf = SLIST_FIRST(&bdev->bc->dirty_list);
 440                 ext4_assert(buf);
 441                 r = ext4_block_flush_buf(bdev, buf);
 442                 if (r != EOK)
 443                         return r;
 444
 445         }
 446         return EOK;
 447 }
 448
 449 int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off)
 450 {
 451         if (on_off)
 452                 bdev->cache_write_back++;
 453
 454         if (!on_off && bdev->cache_write_back)
 455                 bdev->cache_write_back--;
 456
 457         if (bdev->cache_write_back)
 458                 return EOK;
 459
 460         /*Flush data in all delayed cache blocks*/
 461         return ext4_block_cache_flush(bdev);
 462 }
 463
 464 /**
 465  * @}
 466  */