2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2011 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
7 * Created by Charles Manning <charles@aleph1.co.uk>
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.
14 #include "yaffs_checkptrw.h"
15 #include "yaffs_getblockinfo.h"
16 #include "yaffs_endian.h"
18 struct yaffs_checkpt_chunk_hdr {
26 static int apply_chunk_offset(struct yaffs_dev *dev, int chunk)
28 return chunk - dev->chunk_offset;
31 static int apply_block_offset(struct yaffs_dev *dev, int block)
33 return block - dev->block_offset;
37 static void yaffs2_do_endian_hdr(struct yaffs_dev *dev,
38 struct yaffs_checkpt_chunk_hdr *hdr)
40 if (!dev->swap_endian)
42 hdr->version = swap_s32(hdr->version);
43 hdr->seq = swap_s32(hdr->seq);
44 hdr->sum = swap_u32(hdr->sum);
45 hdr->xor = swap_u32(hdr->xor);
48 static void yaffs2_checkpt_init_chunk_hdr(struct yaffs_dev *dev)
50 struct yaffs_checkpt_chunk_hdr hdr;
52 hdr.version = YAFFS_CHECKPOINT_VERSION;
53 hdr.seq = dev->checkpt_page_seq;
54 hdr.sum = dev->checkpt_sum;
55 hdr.xor = dev->checkpt_xor;
57 dev->checkpt_byte_offs = sizeof(hdr);
59 yaffs2_do_endian_hdr(dev, &hdr);
60 memcpy(dev->checkpt_buffer, &hdr, sizeof(hdr));
63 static int yaffs2_checkpt_check_chunk_hdr(struct yaffs_dev *dev)
65 struct yaffs_checkpt_chunk_hdr hdr;
67 memcpy(&hdr, dev->checkpt_buffer, sizeof(hdr));
68 yaffs2_do_endian_hdr(dev, &hdr);
70 dev->checkpt_byte_offs = sizeof(hdr);
72 return hdr.version == YAFFS_CHECKPOINT_VERSION &&
73 hdr.seq == dev->checkpt_page_seq &&
74 hdr.sum == dev->checkpt_sum &&
75 hdr.xor == dev->checkpt_xor;
78 static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
80 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
82 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
83 "checkpt blocks_avail = %d", blocks_avail);
85 return (blocks_avail <= 0) ? 0 : 1;
88 static int yaffs_checkpt_erase(struct yaffs_dev *dev)
92 if (!dev->drv.drv_erase_fn)
94 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
95 "checking blocks %d to %d",
96 dev->internal_start_block, dev->internal_end_block);
98 for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
99 struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
100 int offset_i = apply_block_offset(dev, i);
103 if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
104 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
105 "erasing checkpt block %d", i);
109 result = dev->drv.drv_erase_fn(dev, offset_i);
111 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
112 dev->n_erased_blocks++;
113 dev->n_free_chunks +=
114 dev->param.chunks_per_block;
116 dev->drv.drv_mark_bad_fn(dev, offset_i);
117 bi->block_state = YAFFS_BLOCK_STATE_DEAD;
122 dev->blocks_in_checkpt = 0;
127 static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
130 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
132 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
133 "allocating checkpt block: erased %d reserved %d avail %d next %d ",
134 dev->n_erased_blocks, dev->param.n_reserved_blocks,
135 blocks_avail, dev->checkpt_next_block);
137 if (dev->checkpt_next_block >= 0 &&
138 dev->checkpt_next_block <= dev->internal_end_block &&
141 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
143 struct yaffs_block_info *bi;
145 bi = yaffs_get_block_info(dev, i);
146 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
147 dev->checkpt_next_block = i + 1;
148 dev->checkpt_cur_block = i;
149 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
150 "allocating checkpt block %d", i);
155 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "out of checkpt blocks");
157 dev->checkpt_next_block = -1;
158 dev->checkpt_cur_block = -1;
161 static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
164 struct yaffs_ext_tags tags;
166 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
167 "find next checkpt block: start: blocks %d next %d",
168 dev->blocks_in_checkpt, dev->checkpt_next_block);
170 if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
171 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
173 int chunk = i * dev->param.chunks_per_block;
174 enum yaffs_block_state state;
177 dev->tagger.read_chunk_tags_fn(dev,
178 apply_chunk_offset(dev, chunk),
180 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
181 "find next checkpt block: search: block %d state %d oid %d seq %d eccr %d",
183 tags.obj_id, tags.seq_number,
186 if (tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
189 dev->tagger.query_block_fn(dev,
190 apply_block_offset(dev, i),
192 if (state == YAFFS_BLOCK_STATE_DEAD)
195 /* Right kind of block */
196 dev->checkpt_next_block = tags.obj_id;
197 dev->checkpt_cur_block = i;
198 dev->checkpt_block_list[dev->blocks_in_checkpt] = i;
199 dev->blocks_in_checkpt++;
200 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
201 "found checkpt block %d", i);
205 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "found no more checkpt blocks");
207 dev->checkpt_next_block = -1;
208 dev->checkpt_cur_block = -1;
211 int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
215 dev->checkpt_open_write = writing;
217 /* Got the functions we need? */
218 if (!dev->tagger.write_chunk_tags_fn ||
219 !dev->tagger.read_chunk_tags_fn ||
220 !dev->drv.drv_erase_fn ||
221 !dev->drv.drv_mark_bad_fn)
224 if (writing && !yaffs2_checkpt_space_ok(dev))
227 if (!dev->checkpt_buffer)
228 dev->checkpt_buffer =
229 kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
230 if (!dev->checkpt_buffer)
233 dev->checkpt_page_seq = 0;
234 dev->checkpt_byte_count = 0;
235 dev->checkpt_sum = 0;
236 dev->checkpt_xor = 0;
237 dev->checkpt_cur_block = -1;
238 dev->checkpt_cur_chunk = -1;
239 dev->checkpt_next_block = dev->internal_start_block;
242 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
243 yaffs2_checkpt_init_chunk_hdr(dev);
244 return yaffs_checkpt_erase(dev);
247 /* Opening for a read */
248 /* Set to a value that will kick off a read */
249 dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
250 /* A checkpoint block list of 1 checkpoint block per 16 block is
251 * (hopefully) going to be way more than we need */
252 dev->blocks_in_checkpt = 0;
253 dev->checkpt_max_blocks =
254 (dev->internal_end_block - dev->internal_start_block) / 16 + 2;
255 if (!dev->checkpt_block_list)
256 dev->checkpt_block_list =
257 kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
259 if (!dev->checkpt_block_list)
262 for (i = 0; i < dev->checkpt_max_blocks; i++)
263 dev->checkpt_block_list[i] = -1;
268 int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
272 composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
273 *sum = composite_sum;
277 static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
281 struct yaffs_ext_tags tags;
283 if (dev->checkpt_cur_block < 0) {
284 yaffs2_checkpt_find_erased_block(dev);
285 dev->checkpt_cur_chunk = 0;
288 if (dev->checkpt_cur_block < 0)
292 tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
293 tags.chunk_id = dev->checkpt_page_seq + 1;
294 tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
295 tags.n_bytes = dev->data_bytes_per_chunk;
296 if (dev->checkpt_cur_chunk == 0) {
297 /* First chunk we write for the block? Set block state to
299 struct yaffs_block_info *bi =
300 yaffs_get_block_info(dev, dev->checkpt_cur_block);
301 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
302 dev->blocks_in_checkpt++;
306 dev->checkpt_cur_block * dev->param.chunks_per_block +
307 dev->checkpt_cur_chunk;
309 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
310 "checkpoint wite buffer nand %d(%d:%d) objid %d chId %d",
311 chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk,
312 tags.obj_id, tags.chunk_id);
314 offset_chunk = apply_chunk_offset(dev, chunk);
316 dev->n_page_writes++;
318 dev->tagger.write_chunk_tags_fn(dev, offset_chunk,
319 dev->checkpt_buffer, &tags);
320 dev->checkpt_page_seq++;
321 dev->checkpt_cur_chunk++;
322 if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
323 dev->checkpt_cur_chunk = 0;
324 dev->checkpt_cur_block = -1;
326 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
328 yaffs2_checkpt_init_chunk_hdr(dev);
334 int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
338 u8 *data_bytes = (u8 *) data;
340 if (!dev->checkpt_buffer)
343 if (!dev->checkpt_open_write)
346 while (i < n_bytes && ok) {
347 dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
348 dev->checkpt_sum += *data_bytes;
349 dev->checkpt_xor ^= *data_bytes;
351 dev->checkpt_byte_offs++;
354 dev->checkpt_byte_count++;
356 if (dev->checkpt_byte_offs < 0 ||
357 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
358 ok = yaffs2_checkpt_flush_buffer(dev);
364 int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
367 struct yaffs_ext_tags tags;
370 u8 *data_bytes = (u8 *) data;
372 if (!dev->checkpt_buffer)
375 if (dev->checkpt_open_write)
378 while (i < n_bytes) {
380 if (dev->checkpt_byte_offs < 0 ||
381 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
383 if (dev->checkpt_cur_block < 0) {
384 yaffs2_checkpt_find_block(dev);
385 dev->checkpt_cur_chunk = 0;
388 /* Bail out if we can't find a checpoint block */
389 if (dev->checkpt_cur_block < 0)
392 chunk = dev->checkpt_cur_block *
393 dev->param.chunks_per_block +
394 dev->checkpt_cur_chunk;
396 offset_chunk = apply_chunk_offset(dev, chunk);
399 /* Read in the next chunk */
400 dev->tagger.read_chunk_tags_fn(dev,
405 /* Bail out if the chunk is corrupted. */
406 if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
407 tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
408 tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
411 /* Bail out if it is not a checkpoint chunk. */
412 if(!yaffs2_checkpt_check_chunk_hdr(dev))
415 dev->checkpt_page_seq++;
416 dev->checkpt_cur_chunk++;
418 if (dev->checkpt_cur_chunk >=
419 dev->param.chunks_per_block)
420 dev->checkpt_cur_block = -1;
424 *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
425 dev->checkpt_sum += *data_bytes;
426 dev->checkpt_xor ^= *data_bytes;
427 dev->checkpt_byte_offs++;
430 dev->checkpt_byte_count++;
433 return i; /* Number of bytes read */
436 int yaffs_checkpt_close(struct yaffs_dev *dev)
440 if (dev->checkpt_open_write) {
441 if (dev->checkpt_byte_offs !=
442 sizeof(sizeof(struct yaffs_checkpt_chunk_hdr)))
443 yaffs2_checkpt_flush_buffer(dev);
444 } else if (dev->checkpt_block_list) {
446 i < dev->blocks_in_checkpt &&
447 dev->checkpt_block_list[i] >= 0; i++) {
448 int blk = dev->checkpt_block_list[i];
449 struct yaffs_block_info *bi = NULL;
451 if (dev->internal_start_block <= blk &&
452 blk <= dev->internal_end_block)
453 bi = yaffs_get_block_info(dev, blk);
454 if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
455 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
459 dev->n_free_chunks -=
460 dev->blocks_in_checkpt * dev->param.chunks_per_block;
461 dev->n_erased_blocks -= dev->blocks_in_checkpt;
463 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "checkpoint byte count %d",
464 dev->checkpt_byte_count);
466 if (dev->checkpt_buffer)
472 int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
474 /* Erase the checkpoint data */
476 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
477 "checkpoint invalidate of %d blocks",
478 dev->blocks_in_checkpt);
480 return yaffs_checkpt_erase(dev);