| 1 | /* |
| 2 | * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. |
| 3 | * |
| 4 | * Copyright (C) 2002-2010 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 | |
| 17 | static int yaffs2_checkpt_space_ok(yaffs_dev_t *dev) |
| 18 | { |
| 19 | int blocksAvailable = dev->n_erased_blocks - dev->param.n_reserved_blocks; |
| 20 | |
| 21 | T(YAFFS_TRACE_CHECKPOINT, |
| 22 | (TSTR("checkpt blocks available = %d" TENDSTR), |
| 23 | blocksAvailable)); |
| 24 | |
| 25 | return (blocksAvailable <= 0) ? 0 : 1; |
| 26 | } |
| 27 | |
| 28 | |
| 29 | static int yaffs_checkpt_erase(yaffs_dev_t *dev) |
| 30 | { |
| 31 | int i; |
| 32 | |
| 33 | if (!dev->param.erase_fn) |
| 34 | return 0; |
| 35 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d"TENDSTR), |
| 36 | dev->internal_start_block, dev->internal_end_block)); |
| 37 | |
| 38 | for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) { |
| 39 | yaffs_block_info_t *bi = yaffs_get_block_info(dev, i); |
| 40 | if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) { |
| 41 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("erasing checkpt block %d"TENDSTR), i)); |
| 42 | |
| 43 | dev->n_erasures++; |
| 44 | |
| 45 | if (dev->param.erase_fn(dev, i - dev->block_offset /* realign */)) { |
| 46 | bi->block_state = YAFFS_BLOCK_STATE_EMPTY; |
| 47 | dev->n_erased_blocks++; |
| 48 | dev->n_free_chunks += dev->param.chunks_per_block; |
| 49 | } else { |
| 50 | dev->param.bad_block_fn(dev, i); |
| 51 | bi->block_state = YAFFS_BLOCK_STATE_DEAD; |
| 52 | } |
| 53 | } |
| 54 | } |
| 55 | |
| 56 | dev->blocks_in_checkpt = 0; |
| 57 | |
| 58 | return 1; |
| 59 | } |
| 60 | |
| 61 | |
| 62 | static void yaffs2_checkpt_find_erased_block(yaffs_dev_t *dev) |
| 63 | { |
| 64 | int i; |
| 65 | int blocksAvailable = dev->n_erased_blocks - dev->param.n_reserved_blocks; |
| 66 | T(YAFFS_TRACE_CHECKPOINT, |
| 67 | (TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR), |
| 68 | dev->n_erased_blocks, dev->param.n_reserved_blocks, blocksAvailable, dev->checkpt_next_block)); |
| 69 | |
| 70 | if (dev->checkpt_next_block >= 0 && |
| 71 | dev->checkpt_next_block <= dev->internal_end_block && |
| 72 | blocksAvailable > 0) { |
| 73 | |
| 74 | for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) { |
| 75 | yaffs_block_info_t *bi = yaffs_get_block_info(dev, i); |
| 76 | if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) { |
| 77 | dev->checkpt_next_block = i + 1; |
| 78 | dev->checkpt_cur_block = i; |
| 79 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("allocating checkpt block %d"TENDSTR), i)); |
| 80 | return; |
| 81 | } |
| 82 | } |
| 83 | } |
| 84 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks"TENDSTR))); |
| 85 | |
| 86 | dev->checkpt_next_block = -1; |
| 87 | dev->checkpt_cur_block = -1; |
| 88 | } |
| 89 | |
| 90 | static void yaffs2_checkpt_find_block(yaffs_dev_t *dev) |
| 91 | { |
| 92 | int i; |
| 93 | yaffs_ext_tags tags; |
| 94 | |
| 95 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR), |
| 96 | dev->blocks_in_checkpt, dev->checkpt_next_block)); |
| 97 | |
| 98 | if (dev->blocks_in_checkpt < dev->checkpt_max_blocks) |
| 99 | for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) { |
| 100 | int chunk = i * dev->param.chunks_per_block; |
| 101 | int realignedChunk = chunk - dev->chunk_offset; |
| 102 | |
| 103 | dev->param.read_chunk_tags_fn(dev, realignedChunk, |
| 104 | NULL, &tags); |
| 105 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR), |
| 106 | i, tags.obj_id, tags.seq_number, tags.ecc_result)); |
| 107 | |
| 108 | if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) { |
| 109 | /* Right kind of block */ |
| 110 | dev->checkpt_next_block = tags.obj_id; |
| 111 | dev->checkpt_cur_block = i; |
| 112 | dev->checkpt_block_list[dev->blocks_in_checkpt] = i; |
| 113 | dev->blocks_in_checkpt++; |
| 114 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("found checkpt block %d"TENDSTR), i)); |
| 115 | return; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("found no more checkpt blocks"TENDSTR))); |
| 120 | |
| 121 | dev->checkpt_next_block = -1; |
| 122 | dev->checkpt_cur_block = -1; |
| 123 | } |
| 124 | |
| 125 | |
| 126 | int yaffs2_checkpt_open(yaffs_dev_t *dev, int forWriting) |
| 127 | { |
| 128 | |
| 129 | |
| 130 | dev->checkpt_open_write = forWriting; |
| 131 | |
| 132 | /* Got the functions we need? */ |
| 133 | if (!dev->param.write_chunk_tags_fn || |
| 134 | !dev->param.read_chunk_tags_fn || |
| 135 | !dev->param.erase_fn || |
| 136 | !dev->param.bad_block_fn) |
| 137 | return 0; |
| 138 | |
| 139 | if (forWriting && !yaffs2_checkpt_space_ok(dev)) |
| 140 | return 0; |
| 141 | |
| 142 | if (!dev->checkpt_buffer) |
| 143 | dev->checkpt_buffer = YMALLOC_DMA(dev->param.total_bytes_per_chunk); |
| 144 | if (!dev->checkpt_buffer) |
| 145 | return 0; |
| 146 | |
| 147 | |
| 148 | dev->checkpt_page_seq = 0; |
| 149 | dev->checkpt_byte_count = 0; |
| 150 | dev->checkpt_sum = 0; |
| 151 | dev->checkpt_xor = 0; |
| 152 | dev->checkpt_cur_block = -1; |
| 153 | dev->checkpt_cur_chunk = -1; |
| 154 | dev->checkpt_next_block = dev->internal_start_block; |
| 155 | |
| 156 | /* Erase all the blocks in the checkpoint area */ |
| 157 | if (forWriting) { |
| 158 | memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk); |
| 159 | dev->checkpt_byte_offs = 0; |
| 160 | return yaffs_checkpt_erase(dev); |
| 161 | } else { |
| 162 | int i; |
| 163 | /* Set to a value that will kick off a read */ |
| 164 | dev->checkpt_byte_offs = dev->data_bytes_per_chunk; |
| 165 | /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully) |
| 166 | * going to be way more than we need */ |
| 167 | dev->blocks_in_checkpt = 0; |
| 168 | dev->checkpt_max_blocks = (dev->internal_end_block - dev->internal_start_block)/16 + 2; |
| 169 | dev->checkpt_block_list = YMALLOC(sizeof(int) * dev->checkpt_max_blocks); |
| 170 | if(!dev->checkpt_block_list) |
| 171 | return 0; |
| 172 | |
| 173 | for (i = 0; i < dev->checkpt_max_blocks; i++) |
| 174 | dev->checkpt_block_list[i] = -1; |
| 175 | } |
| 176 | |
| 177 | return 1; |
| 178 | } |
| 179 | |
| 180 | int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum) |
| 181 | { |
| 182 | __u32 compositeSum; |
| 183 | compositeSum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF); |
| 184 | *sum = compositeSum; |
| 185 | return 1; |
| 186 | } |
| 187 | |
| 188 | static int yaffs2_checkpt_flush_buffer(yaffs_dev_t *dev) |
| 189 | { |
| 190 | int chunk; |
| 191 | int realignedChunk; |
| 192 | |
| 193 | yaffs_ext_tags tags; |
| 194 | |
| 195 | if (dev->checkpt_cur_block < 0) { |
| 196 | yaffs2_checkpt_find_erased_block(dev); |
| 197 | dev->checkpt_cur_chunk = 0; |
| 198 | } |
| 199 | |
| 200 | if (dev->checkpt_cur_block < 0) |
| 201 | return 0; |
| 202 | |
| 203 | tags.is_deleted = 0; |
| 204 | tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */ |
| 205 | tags.chunk_id = dev->checkpt_page_seq + 1; |
| 206 | tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA; |
| 207 | tags.n_bytes = dev->data_bytes_per_chunk; |
| 208 | if (dev->checkpt_cur_chunk == 0) { |
| 209 | /* First chunk we write for the block? Set block state to |
| 210 | checkpoint */ |
| 211 | yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->checkpt_cur_block); |
| 212 | bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT; |
| 213 | dev->blocks_in_checkpt++; |
| 214 | } |
| 215 | |
| 216 | chunk = dev->checkpt_cur_block * dev->param.chunks_per_block + dev->checkpt_cur_chunk; |
| 217 | |
| 218 | |
| 219 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR), |
| 220 | chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk, tags.obj_id, tags.chunk_id)); |
| 221 | |
| 222 | realignedChunk = chunk - dev->chunk_offset; |
| 223 | |
| 224 | dev->n_page_writes++; |
| 225 | |
| 226 | dev->param.write_chunk_tags_fn(dev, realignedChunk, |
| 227 | dev->checkpt_buffer, &tags); |
| 228 | dev->checkpt_byte_offs = 0; |
| 229 | dev->checkpt_page_seq++; |
| 230 | dev->checkpt_cur_chunk++; |
| 231 | if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) { |
| 232 | dev->checkpt_cur_chunk = 0; |
| 233 | dev->checkpt_cur_block = -1; |
| 234 | } |
| 235 | memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk); |
| 236 | |
| 237 | return 1; |
| 238 | } |
| 239 | |
| 240 | |
| 241 | int yaffs2_checkpt_wr(yaffs_dev_t *dev, const void *data, int n_bytes) |
| 242 | { |
| 243 | int i = 0; |
| 244 | int ok = 1; |
| 245 | |
| 246 | |
| 247 | __u8 * dataBytes = (__u8 *)data; |
| 248 | |
| 249 | |
| 250 | |
| 251 | if (!dev->checkpt_buffer) |
| 252 | return 0; |
| 253 | |
| 254 | if (!dev->checkpt_open_write) |
| 255 | return -1; |
| 256 | |
| 257 | while (i < n_bytes && ok) { |
| 258 | dev->checkpt_buffer[dev->checkpt_byte_offs] = *dataBytes; |
| 259 | dev->checkpt_sum += *dataBytes; |
| 260 | dev->checkpt_xor ^= *dataBytes; |
| 261 | |
| 262 | dev->checkpt_byte_offs++; |
| 263 | i++; |
| 264 | dataBytes++; |
| 265 | dev->checkpt_byte_count++; |
| 266 | |
| 267 | |
| 268 | if (dev->checkpt_byte_offs < 0 || |
| 269 | dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) |
| 270 | ok = yaffs2_checkpt_flush_buffer(dev); |
| 271 | } |
| 272 | |
| 273 | return i; |
| 274 | } |
| 275 | |
| 276 | int yaffs2_checkpt_rd(yaffs_dev_t *dev, void *data, int n_bytes) |
| 277 | { |
| 278 | int i = 0; |
| 279 | int ok = 1; |
| 280 | yaffs_ext_tags tags; |
| 281 | |
| 282 | |
| 283 | int chunk; |
| 284 | int realignedChunk; |
| 285 | |
| 286 | __u8 *dataBytes = (__u8 *)data; |
| 287 | |
| 288 | if (!dev->checkpt_buffer) |
| 289 | return 0; |
| 290 | |
| 291 | if (dev->checkpt_open_write) |
| 292 | return -1; |
| 293 | |
| 294 | while (i < n_bytes && ok) { |
| 295 | |
| 296 | |
| 297 | if (dev->checkpt_byte_offs < 0 || |
| 298 | dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) { |
| 299 | |
| 300 | if (dev->checkpt_cur_block < 0) { |
| 301 | yaffs2_checkpt_find_block(dev); |
| 302 | dev->checkpt_cur_chunk = 0; |
| 303 | } |
| 304 | |
| 305 | if (dev->checkpt_cur_block < 0) |
| 306 | ok = 0; |
| 307 | else { |
| 308 | chunk = dev->checkpt_cur_block * |
| 309 | dev->param.chunks_per_block + |
| 310 | dev->checkpt_cur_chunk; |
| 311 | |
| 312 | realignedChunk = chunk - dev->chunk_offset; |
| 313 | |
| 314 | dev->n_page_reads++; |
| 315 | |
| 316 | /* read in the next chunk */ |
| 317 | /* printf("read checkpoint page %d\n",dev->checkpointPage); */ |
| 318 | dev->param.read_chunk_tags_fn(dev, |
| 319 | realignedChunk, |
| 320 | dev->checkpt_buffer, |
| 321 | &tags); |
| 322 | |
| 323 | if (tags.chunk_id != (dev->checkpt_page_seq + 1) || |
| 324 | tags.ecc_result > YAFFS_ECC_RESULT_FIXED || |
| 325 | tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA) |
| 326 | ok = 0; |
| 327 | |
| 328 | dev->checkpt_byte_offs = 0; |
| 329 | dev->checkpt_page_seq++; |
| 330 | dev->checkpt_cur_chunk++; |
| 331 | |
| 332 | if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) |
| 333 | dev->checkpt_cur_block = -1; |
| 334 | } |
| 335 | } |
| 336 | |
| 337 | if (ok) { |
| 338 | *dataBytes = dev->checkpt_buffer[dev->checkpt_byte_offs]; |
| 339 | dev->checkpt_sum += *dataBytes; |
| 340 | dev->checkpt_xor ^= *dataBytes; |
| 341 | dev->checkpt_byte_offs++; |
| 342 | i++; |
| 343 | dataBytes++; |
| 344 | dev->checkpt_byte_count++; |
| 345 | } |
| 346 | } |
| 347 | |
| 348 | return i; |
| 349 | } |
| 350 | |
| 351 | int yaffs_checkpt_close(yaffs_dev_t *dev) |
| 352 | { |
| 353 | |
| 354 | if (dev->checkpt_open_write) { |
| 355 | if (dev->checkpt_byte_offs != 0) |
| 356 | yaffs2_checkpt_flush_buffer(dev); |
| 357 | } else if(dev->checkpt_block_list){ |
| 358 | int i; |
| 359 | for (i = 0; i < dev->blocks_in_checkpt && dev->checkpt_block_list[i] >= 0; i++) { |
| 360 | int blk = dev->checkpt_block_list[i]; |
| 361 | yaffs_block_info_t *bi = NULL; |
| 362 | if( dev->internal_start_block <= blk && blk <= dev->internal_end_block) |
| 363 | bi = yaffs_get_block_info(dev, blk); |
| 364 | if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY) |
| 365 | bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT; |
| 366 | else { |
| 367 | /* Todo this looks odd... */ |
| 368 | } |
| 369 | } |
| 370 | YFREE(dev->checkpt_block_list); |
| 371 | dev->checkpt_block_list = NULL; |
| 372 | } |
| 373 | |
| 374 | dev->n_free_chunks -= dev->blocks_in_checkpt * dev->param.chunks_per_block; |
| 375 | dev->n_erased_blocks -= dev->blocks_in_checkpt; |
| 376 | |
| 377 | |
| 378 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR), |
| 379 | dev->checkpt_byte_count)); |
| 380 | |
| 381 | if (dev->checkpt_buffer) { |
| 382 | /* free the buffer */ |
| 383 | YFREE(dev->checkpt_buffer); |
| 384 | dev->checkpt_buffer = NULL; |
| 385 | return 1; |
| 386 | } else |
| 387 | return 0; |
| 388 | } |
| 389 | |
| 390 | int yaffs2_checkpt_invalidate_stream(yaffs_dev_t *dev) |
| 391 | { |
| 392 | /* Erase the checkpoint data */ |
| 393 | |
| 394 | T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint invalidate of %d blocks"TENDSTR), |
| 395 | dev->blocks_in_checkpt)); |
| 396 | |
| 397 | return yaffs_checkpt_erase(dev); |
| 398 | } |
| 399 | |
| 400 | |
| 401 | |
| 402 | |
