uboot/fs/yaffs2/yaffs_checkptrw.c
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   1/*
   2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3 *
   4 * Copyright (C) 2002-2011 Aleph One Ltd.
   5 *   for Toby Churchill Ltd and Brightstar Engineering
   6 *
   7 * Created by Charles Manning <charles@aleph1.co.uk>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include "yaffs_checkptrw.h"
  15#include "yaffs_getblockinfo.h"
  16#include <dm/devres.h>
  17
  18static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
  19{
  20        int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
  21
  22        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
  23                "checkpt blocks_avail = %d", blocks_avail);
  24
  25        return (blocks_avail <= 0) ? 0 : 1;
  26}
  27
  28static int yaffs_checkpt_erase(struct yaffs_dev *dev)
  29{
  30        int i;
  31
  32        if (!dev->param.erase_fn)
  33                return 0;
  34        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
  35                "checking blocks %d to %d",
  36                dev->internal_start_block, dev->internal_end_block);
  37
  38        for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
  39                struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
  40                if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
  41                        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
  42                        "erasing checkpt block %d", i);
  43
  44                        dev->n_erasures++;
  45
  46                        if (dev->param.
  47                            erase_fn(dev,
  48                                     i - dev->block_offset /* realign */)) {
  49                                bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
  50                                dev->n_erased_blocks++;
  51                                dev->n_free_chunks +=
  52                                    dev->param.chunks_per_block;
  53                        } else {
  54                                dev->param.bad_block_fn(dev, i);
  55                                bi->block_state = YAFFS_BLOCK_STATE_DEAD;
  56                        }
  57                }
  58        }
  59
  60        dev->blocks_in_checkpt = 0;
  61
  62        return 1;
  63}
  64
  65static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
  66{
  67        int i;
  68        int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
  69
  70        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
  71                "allocating checkpt block: erased %d reserved %d avail %d next %d ",
  72                dev->n_erased_blocks, dev->param.n_reserved_blocks,
  73                blocks_avail, dev->checkpt_next_block);
  74
  75        if (dev->checkpt_next_block >= 0 &&
  76            dev->checkpt_next_block <= dev->internal_end_block &&
  77            blocks_avail > 0) {
  78
  79                for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
  80                     i++) {
  81                        struct yaffs_block_info *bi =
  82                            yaffs_get_block_info(dev, i);
  83                        if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
  84                                dev->checkpt_next_block = i + 1;
  85                                dev->checkpt_cur_block = i;
  86                                yaffs_trace(YAFFS_TRACE_CHECKPOINT,
  87                                        "allocating checkpt block %d", i);
  88                                return;
  89                        }
  90                }
  91        }
  92        yaffs_trace(YAFFS_TRACE_CHECKPOINT, "out of checkpt blocks");
  93
  94        dev->checkpt_next_block = -1;
  95        dev->checkpt_cur_block = -1;
  96}
  97
  98static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
  99{
 100        int i;
 101        struct yaffs_ext_tags tags;
 102
 103        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
 104                "find next checkpt block: start:  blocks %d next %d",
 105                dev->blocks_in_checkpt, dev->checkpt_next_block);
 106
 107        if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
 108                for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
 109                     i++) {
 110                        int chunk = i * dev->param.chunks_per_block;
 111                        int realigned_chunk = chunk - dev->chunk_offset;
 112
 113                        dev->param.read_chunk_tags_fn(dev, realigned_chunk,
 114                                                      NULL, &tags);
 115                        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
 116                                "find next checkpt block: search: block %d oid %d seq %d eccr %d",
 117                                i, tags.obj_id, tags.seq_number,
 118                                tags.ecc_result);
 119
 120                        if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
 121                                /* Right kind of block */
 122                                dev->checkpt_next_block = tags.obj_id;
 123                                dev->checkpt_cur_block = i;
 124                                dev->checkpt_block_list[dev->
 125                                                        blocks_in_checkpt] = i;
 126                                dev->blocks_in_checkpt++;
 127                                yaffs_trace(YAFFS_TRACE_CHECKPOINT,
 128                                        "found checkpt block %d", i);
 129                                return;
 130                        }
 131                }
 132
 133        yaffs_trace(YAFFS_TRACE_CHECKPOINT, "found no more checkpt blocks");
 134
 135        dev->checkpt_next_block = -1;
 136        dev->checkpt_cur_block = -1;
 137}
 138
 139int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
 140{
 141        int i;
 142
 143        dev->checkpt_open_write = writing;
 144
 145        /* Got the functions we need? */
 146        if (!dev->param.write_chunk_tags_fn ||
 147            !dev->param.read_chunk_tags_fn ||
 148            !dev->param.erase_fn || !dev->param.bad_block_fn)
 149                return 0;
 150
 151        if (writing && !yaffs2_checkpt_space_ok(dev))
 152                return 0;
 153
 154        if (!dev->checkpt_buffer)
 155                dev->checkpt_buffer =
 156                    kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
 157        if (!dev->checkpt_buffer)
 158                return 0;
 159
 160        dev->checkpt_page_seq = 0;
 161        dev->checkpt_byte_count = 0;
 162        dev->checkpt_sum = 0;
 163        dev->checkpt_xor = 0;
 164        dev->checkpt_cur_block = -1;
 165        dev->checkpt_cur_chunk = -1;
 166        dev->checkpt_next_block = dev->internal_start_block;
 167
 168        /* Erase all the blocks in the checkpoint area */
 169        if (writing) {
 170                memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
 171                dev->checkpt_byte_offs = 0;
 172                return yaffs_checkpt_erase(dev);
 173        }
 174
 175        /* Set to a value that will kick off a read */
 176        dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
 177        /* A checkpoint block list of 1 checkpoint block per 16 block is
 178         * (hopefully) going to be way more than we need */
 179        dev->blocks_in_checkpt = 0;
 180        dev->checkpt_max_blocks =
 181            (dev->internal_end_block - dev->internal_start_block) / 16 + 2;
 182        dev->checkpt_block_list =
 183            kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
 184
 185        if (!dev->checkpt_block_list)
 186                return 0;
 187
 188        for (i = 0; i < dev->checkpt_max_blocks; i++)
 189                dev->checkpt_block_list[i] = -1;
 190
 191        return 1;
 192}
 193
 194int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
 195{
 196        u32 composite_sum;
 197
 198        composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
 199        *sum = composite_sum;
 200        return 1;
 201}
 202
 203static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
 204{
 205        int chunk;
 206        int realigned_chunk;
 207        struct yaffs_ext_tags tags;
 208
 209        if (dev->checkpt_cur_block < 0) {
 210                yaffs2_checkpt_find_erased_block(dev);
 211                dev->checkpt_cur_chunk = 0;
 212        }
 213
 214        if (dev->checkpt_cur_block < 0)
 215                return 0;
 216
 217        tags.is_deleted = 0;
 218        tags.obj_id = dev->checkpt_next_block;  /* Hint to next place to look */
 219        tags.chunk_id = dev->checkpt_page_seq + 1;
 220        tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
 221        tags.n_bytes = dev->data_bytes_per_chunk;
 222        if (dev->checkpt_cur_chunk == 0) {
 223                /* First chunk we write for the block? Set block state to
 224                   checkpoint */
 225                struct yaffs_block_info *bi =
 226                    yaffs_get_block_info(dev, dev->checkpt_cur_block);
 227                bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
 228                dev->blocks_in_checkpt++;
 229        }
 230
 231        chunk =
 232            dev->checkpt_cur_block * dev->param.chunks_per_block +
 233            dev->checkpt_cur_chunk;
 234
 235        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
 236                "checkpoint wite buffer nand %d(%d:%d) objid %d chId %d",
 237                chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk,
 238                tags.obj_id, tags.chunk_id);
 239
 240        realigned_chunk = chunk - dev->chunk_offset;
 241
 242        dev->n_page_writes++;
 243
 244        dev->param.write_chunk_tags_fn(dev, realigned_chunk,
 245                                       dev->checkpt_buffer, &tags);
 246        dev->checkpt_byte_offs = 0;
 247        dev->checkpt_page_seq++;
 248        dev->checkpt_cur_chunk++;
 249        if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
 250                dev->checkpt_cur_chunk = 0;
 251                dev->checkpt_cur_block = -1;
 252        }
 253        memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
 254
 255        return 1;
 256}
 257
 258int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
 259{
 260        int i = 0;
 261        int ok = 1;
 262        u8 *data_bytes = (u8 *) data;
 263
 264        if (!dev->checkpt_buffer)
 265                return 0;
 266
 267        if (!dev->checkpt_open_write)
 268                return -1;
 269
 270        while (i < n_bytes && ok) {
 271                dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
 272                dev->checkpt_sum += *data_bytes;
 273                dev->checkpt_xor ^= *data_bytes;
 274
 275                dev->checkpt_byte_offs++;
 276                i++;
 277                data_bytes++;
 278                dev->checkpt_byte_count++;
 279
 280                if (dev->checkpt_byte_offs < 0 ||
 281                    dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
 282                        ok = yaffs2_checkpt_flush_buffer(dev);
 283        }
 284
 285        return i;
 286}
 287
 288int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
 289{
 290        int i = 0;
 291        int ok = 1;
 292        struct yaffs_ext_tags tags;
 293        int chunk;
 294        int realigned_chunk;
 295        u8 *data_bytes = (u8 *) data;
 296
 297        if (!dev->checkpt_buffer)
 298                return 0;
 299
 300        if (dev->checkpt_open_write)
 301                return -1;
 302
 303        while (i < n_bytes && ok) {
 304
 305                if (dev->checkpt_byte_offs < 0 ||
 306                    dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
 307
 308                        if (dev->checkpt_cur_block < 0) {
 309                                yaffs2_checkpt_find_block(dev);
 310                                dev->checkpt_cur_chunk = 0;
 311                        }
 312
 313                        if (dev->checkpt_cur_block < 0) {
 314                                ok = 0;
 315                                break;
 316                        }
 317
 318                        chunk = dev->checkpt_cur_block *
 319                            dev->param.chunks_per_block +
 320                            dev->checkpt_cur_chunk;
 321
 322                        realigned_chunk = chunk - dev->chunk_offset;
 323                        dev->n_page_reads++;
 324
 325                        /* read in the next chunk */
 326                        dev->param.read_chunk_tags_fn(dev,
 327                                                realigned_chunk,
 328                                                dev->checkpt_buffer,
 329                                                &tags);
 330
 331                        if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
 332                            tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
 333                            tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA) {
 334                                ok = 0;
 335                                break;
 336                        }
 337
 338                        dev->checkpt_byte_offs = 0;
 339                        dev->checkpt_page_seq++;
 340                        dev->checkpt_cur_chunk++;
 341
 342                        if (dev->checkpt_cur_chunk >=
 343                                        dev->param.chunks_per_block)
 344                                dev->checkpt_cur_block = -1;
 345                }
 346
 347                *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
 348                dev->checkpt_sum += *data_bytes;
 349                dev->checkpt_xor ^= *data_bytes;
 350                dev->checkpt_byte_offs++;
 351                i++;
 352                data_bytes++;
 353                dev->checkpt_byte_count++;
 354        }
 355
 356        return i;
 357}
 358
 359int yaffs_checkpt_close(struct yaffs_dev *dev)
 360{
 361        int i;
 362
 363        if (dev->checkpt_open_write) {
 364                if (dev->checkpt_byte_offs != 0)
 365                        yaffs2_checkpt_flush_buffer(dev);
 366        } else if (dev->checkpt_block_list) {
 367                for (i = 0;
 368                     i < dev->blocks_in_checkpt &&
 369                     dev->checkpt_block_list[i] >= 0; i++) {
 370                        int blk = dev->checkpt_block_list[i];
 371                        struct yaffs_block_info *bi = NULL;
 372
 373                        if (dev->internal_start_block <= blk &&
 374                            blk <= dev->internal_end_block)
 375                                bi = yaffs_get_block_info(dev, blk);
 376                        if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
 377                                bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
 378                }
 379                kfree(dev->checkpt_block_list);
 380                dev->checkpt_block_list = NULL;
 381        }
 382
 383        dev->n_free_chunks -=
 384                dev->blocks_in_checkpt * dev->param.chunks_per_block;
 385        dev->n_erased_blocks -= dev->blocks_in_checkpt;
 386
 387        yaffs_trace(YAFFS_TRACE_CHECKPOINT, "checkpoint byte count %d",
 388                dev->checkpt_byte_count);
 389
 390        if (dev->checkpt_buffer) {
 391                /* free the buffer */
 392                kfree(dev->checkpt_buffer);
 393                dev->checkpt_buffer = NULL;
 394                return 1;
 395        } else {
 396                return 0;
 397        }
 398}
 399
 400int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
 401{
 402        /* Erase the checkpoint data */
 403
 404        yaffs_trace(YAFFS_TRACE_CHECKPOINT,
 405                "checkpoint invalidate of %d blocks",
 406                dev->blocks_in_checkpt);
 407
 408        return yaffs_checkpt_erase(dev);
 409}
 410