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 17static 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 29static 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 62static 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 90static 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 126int 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 180int 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 188static 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 241int 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 276int 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 351int 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 390int 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