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
 148                 if (r) {
 149                         if (buf->end_write)
 150                                 buf->end_write(bc, buf, r, buf->end_write_arg);
 151
 152                         return r;
 153                 }
 154
 155                 ext4_bcache_remove_dirty_node(bc, buf);
 156                 ext4_bcache_clear_flag(buf, BC_DIRTY);
 157                 if (buf->end_write)
 158                         buf->end_write(bc, buf, r, buf->end_write_arg);
 159
 160         }
 161         return EOK;
 162 }
 163
 164 int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba)
 165 {
 166         int r = EOK;
 167         struct ext4_buf *buf;
 168         struct ext4_block b;
 169         buf = ext4_bcache_find_get(bdev->bc, &b, lba);
 170         if (buf) {
 171                 r = ext4_block_flush_buf(bdev, buf);
 172                 ext4_bcache_free(bdev->bc, &b);
 173         }
 174         return r;
 175 }
 176
 177 int ext4_block_cache_shake(struct ext4_blockdev *bdev)
 178 {
 179         struct ext4_buf *buf;
 180         while (!RB_EMPTY(&bdev->bc->lru_root) &&
 181                 ext4_bcache_is_full(bdev->bc)) {
 182
 183                 buf = ext4_buf_lowest_lru(bdev->bc);
 184                 ext4_assert(buf);
 185                 if (ext4_bcache_test_flag(buf, BC_DIRTY)) {
 186                         int r = ext4_block_flush_buf(bdev, buf);
 187                         if (r != EOK)
 188                                 return r;
 189
 190                 }
 191
 192                 ext4_bcache_drop_buf(bdev->bc, buf);
 193         }
 194         return EOK;
 195 }
 196
 197 int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
 198                           uint64_t lba)
 199 {
 200         bool is_new;
 201         int r;
 202
 203         ext4_assert(bdev && b);
 204
 205         if (!bdev->bdif->ph_refctr)
 206                 return EIO;
 207
 208         if (!(lba < bdev->lg_bcnt))
 209                 return ERANGE;
 210
 211         b->lb_id = lba;
 212
 213         /*If cache is full we have to (flush and) drop it anyway :(*/
 214         r = ext4_block_cache_shake(bdev);
 215         if (r != EOK)
 216                 return r;
 217
 218         r = ext4_bcache_alloc(bdev->bc, b, &is_new);
 219         if (r != EOK)
 220                 return r;
 221
 222         if (!b->data)
 223                 return ENOMEM;
 224
 225         return EOK;
 226 }
 227
 228 int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
 229                    uint64_t lba)
 230 {
 231         int r = ext4_block_get_noread(bdev, b, lba);
 232         if (r != EOK)
 233                 return r;
 234
 235         if (ext4_bcache_test_flag(b->buf, BC_UPTODATE)) {
 236                 /* Data in the cache is up-to-date.
 237                  * Reading from physical device is not required */
 238                 return EOK;
 239         }
 240
 241         r = ext4_blocks_get_direct(bdev, b->data, lba, 1);
 242         if (r != EOK) {
 243                 ext4_bcache_free(bdev->bc, b);
 244                 b->lb_id = 0;
 245                 return r;
 246         }
 247
 248         /* Mark buffer up-to-date, since
 249          * fresh data is read from physical device just now. */
 250         ext4_bcache_set_flag(b->buf, BC_UPTODATE);
 251         return EOK;
 252 }
 253
 254 int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b)
 255 {
 256         ext4_assert(bdev && b);
 257         ext4_assert(b->buf);
 258
 259         if (!bdev->bdif->ph_refctr)
 260                 return EIO;
 261
 262         return ext4_bcache_free(bdev->bc, b);
 263 }
 264
 265 int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
 266                            uint32_t cnt)
 267 {
 268         uint64_t pba;
 269         uint32_t pb_cnt;
 270
 271         ext4_assert(bdev && buf);
 272
 273         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 274         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 275
 276         return ext4_bdif_bread(bdev, buf, pba, pb_cnt * cnt);
 277 }
 278
 279 int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
 280                            uint64_t lba, uint32_t cnt)
 281 {
 282         uint64_t pba;
 283         uint32_t pb_cnt;
 284
 285         ext4_assert(bdev && buf);
 286
 287         pba = (lba * bdev->lg_bsize + bdev->part_offset) / bdev->bdif->ph_bsize;
 288         pb_cnt = bdev->lg_bsize / bdev->bdif->ph_bsize;
 289
 290         return ext4_bdif_bwrite(bdev, buf, pba, pb_cnt * cnt);
 291 }
 292
 293 int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
 294                           const void *buf, uint32_t len)
 295 {
 296         uint64_t block_idx;
 297         uint32_t blen;
 298         uint32_t unalg;
 299         int r = EOK;
 300
 301         const uint8_t *p = (void *)buf;
 302
 303         ext4_assert(bdev && buf);
 304
 305         if (!bdev->bdif->ph_refctr)
 306                 return EIO;
 307
 308         if (off + len > bdev->part_size)
 309                 return EINVAL; /*Ups. Out of range operation*/
 310
 311         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 312
 313         /*OK lets deal with the first possible unaligned block*/
 314         unalg = (off & (bdev->bdif->ph_bsize - 1));
 315         if (unalg) {
 316
 317                 uint32_t wlen = (bdev->bdif->ph_bsize - unalg) > len
 318                                     ? len
 319                                     : (bdev->bdif->ph_bsize - unalg);
 320
 321                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 322                 if (r != EOK)
 323                         return r;
 324
 325                 memcpy(bdev->bdif->ph_bbuf + unalg, p, wlen);
 326                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 327                 if (r != EOK)
 328                         return r;
 329
 330                 p += wlen;
 331                 len -= wlen;
 332                 block_idx++;
 333         }
 334
 335         /*Aligned data*/
 336         blen = len / bdev->bdif->ph_bsize;
 337         r = ext4_bdif_bwrite(bdev, p, block_idx, blen);
 338         if (r != EOK)
 339                 return r;
 340
 341         p += bdev->bdif->ph_bsize * blen;
 342         len -= bdev->bdif->ph_bsize * blen;
 343
 344         block_idx += blen;
 345
 346         /*Rest of the data*/
 347         if (len) {
 348                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 349                 if (r != EOK)
 350                         return r;
 351
 352                 memcpy(bdev->bdif->ph_bbuf, p, len);
 353                 r = ext4_bdif_bwrite(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 354                 if (r != EOK)
 355                         return r;
 356         }
 357
 358         return r;
 359 }
 360
 361 int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
 362                          uint32_t len)
 363 {
 364         uint64_t block_idx;
 365         uint32_t blen;
 366         uint32_t unalg;
 367         int r = EOK;
 368
 369         uint8_t *p = (void *)buf;
 370
 371         ext4_assert(bdev && buf);
 372
 373         if (!bdev->bdif->ph_refctr)
 374                 return EIO;
 375
 376         if (off + len > bdev->part_size)
 377                 return EINVAL; /*Ups. Out of range operation*/
 378
 379         block_idx = ((off + bdev->part_offset) / bdev->bdif->ph_bsize);
 380
 381         /*OK lets deal with the first possible unaligned block*/
 382         unalg = (off & (bdev->bdif->ph_bsize - 1));
 383         if (unalg) {
 384
 385                 uint32_t rlen = (bdev->bdif->ph_bsize - unalg) > len
 386                                     ? len
 387                                     : (bdev->bdif->ph_bsize - unalg);
 388
 389                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 390                 if (r != EOK)
 391                         return r;
 392
 393                 memcpy(p, bdev->bdif->ph_bbuf + unalg, rlen);
 394
 395                 p += rlen;
 396                 len -= rlen;
 397                 block_idx++;
 398         }
 399
 400         /*Aligned data*/
 401         blen = len / bdev->bdif->ph_bsize;
 402
 403         r = ext4_bdif_bread(bdev, p, block_idx, blen);
 404         if (r != EOK)
 405                 return r;
 406
 407         p += bdev->bdif->ph_bsize * blen;
 408         len -= bdev->bdif->ph_bsize * blen;
 409
 410         block_idx += blen;
 411
 412         /*Rest of the data*/
 413         if (len) {
 414                 r = ext4_bdif_bread(bdev, bdev->bdif->ph_bbuf, block_idx, 1);
 415                 if (r != EOK)
 416                         return r;
 417
 418                 memcpy(p, bdev->bdif->ph_bbuf, len);
 419         }
 420
 421         return r;
 422 }
 423
 424 int ext4_block_cache_flush(struct ext4_blockdev *bdev)
 425 {
 426         while (!SLIST_EMPTY(&bdev->bc->dirty_list)) {
 427                 int r;
 428                 struct ext4_buf *buf = SLIST_FIRST(&bdev->bc->dirty_list);
 429                 ext4_assert(buf);
 430                 r = ext4_block_flush_buf(bdev, buf);
 431                 if (r != EOK)
 432                         return r;
 433
 434         }
 435         return EOK;
 436 }
 437
 438 int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off)
 439 {
 440         if (on_off)
 441                 bdev->cache_write_back++;
 442
 443         if (!on_off && bdev->cache_write_back)
 444                 bdev->cache_write_back--;
 445
 446         if (bdev->cache_write_back)
 447                 return EOK;
 448
 449         /*Flush data in all delayed cache blocks*/
 450         return ext4_block_cache_flush(bdev);
 451 }
 452
 453 /**
 454  * @}
 455  */