2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2010 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"
17 static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
19 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
21 T(YAFFS_TRACE_CHECKPOINT,
22 (TSTR("checkpt blocks available = %d" TENDSTR), blocks_avail));
24 return (blocks_avail <= 0) ? 0 : 1;
27 static int yaffs_checkpt_erase(struct yaffs_dev *dev)
31 if (!dev->param.erase_fn)
33 T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d" TENDSTR),
34 dev->internal_start_block,
35 dev->internal_end_block));
37 for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
38 struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
39 if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
40 T(YAFFS_TRACE_CHECKPOINT,
41 (TSTR("erasing checkpt block %d" TENDSTR), i));
47 i - dev->block_offset /* realign */ )) {
48 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
49 dev->n_erased_blocks++;
51 dev->param.chunks_per_block;
53 dev->param.bad_block_fn(dev, i);
54 bi->block_state = YAFFS_BLOCK_STATE_DEAD;
59 dev->blocks_in_checkpt = 0;
64 static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
67 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
68 T(YAFFS_TRACE_CHECKPOINT,
70 ("allocating checkpt block: erased %d reserved %d avail %d next %d "
71 TENDSTR), dev->n_erased_blocks, dev->param.n_reserved_blocks,
72 blocks_avail, dev->checkpt_next_block));
74 if (dev->checkpt_next_block >= 0 &&
75 dev->checkpt_next_block <= dev->internal_end_block &&
78 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
80 struct yaffs_block_info *bi =
81 yaffs_get_block_info(dev, i);
82 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
83 dev->checkpt_next_block = i + 1;
84 dev->checkpt_cur_block = i;
85 T(YAFFS_TRACE_CHECKPOINT,
86 (TSTR("allocating checkpt block %d" TENDSTR),
92 T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks" TENDSTR)));
94 dev->checkpt_next_block = -1;
95 dev->checkpt_cur_block = -1;
98 static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
101 struct yaffs_ext_tags tags;
103 T(YAFFS_TRACE_CHECKPOINT,
104 (TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
105 dev->blocks_in_checkpt, dev->checkpt_next_block));
107 if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
108 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
110 int chunk = i * dev->param.chunks_per_block;
111 int realigned_chunk = chunk - dev->chunk_offset;
113 dev->param.read_chunk_tags_fn(dev, realigned_chunk,
115 T(YAFFS_TRACE_CHECKPOINT,
117 ("find next checkpt block: search: block %d oid %d seq %d eccr %d"
118 TENDSTR), i, tags.obj_id, tags.seq_number,
121 if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
122 /* Right kind of block */
123 dev->checkpt_next_block = tags.obj_id;
124 dev->checkpt_cur_block = i;
125 dev->checkpt_block_list[dev->
126 blocks_in_checkpt] = i;
127 dev->blocks_in_checkpt++;
128 T(YAFFS_TRACE_CHECKPOINT,
129 (TSTR("found checkpt block %d" TENDSTR), i));
134 T(YAFFS_TRACE_CHECKPOINT,
135 (TSTR("found no more checkpt blocks" TENDSTR)));
137 dev->checkpt_next_block = -1;
138 dev->checkpt_cur_block = -1;
141 int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
144 dev->checkpt_open_write = writing;
146 /* Got the functions we need? */
147 if (!dev->param.write_chunk_tags_fn ||
148 !dev->param.read_chunk_tags_fn ||
149 !dev->param.erase_fn || !dev->param.bad_block_fn)
152 if (writing && !yaffs2_checkpt_space_ok(dev))
155 if (!dev->checkpt_buffer)
156 dev->checkpt_buffer =
157 kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
158 if (!dev->checkpt_buffer)
161 dev->checkpt_page_seq = 0;
162 dev->checkpt_byte_count = 0;
163 dev->checkpt_sum = 0;
164 dev->checkpt_xor = 0;
165 dev->checkpt_cur_block = -1;
166 dev->checkpt_cur_chunk = -1;
167 dev->checkpt_next_block = dev->internal_start_block;
169 /* Erase all the blocks in the checkpoint area */
171 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
172 dev->checkpt_byte_offs = 0;
173 return yaffs_checkpt_erase(dev);
176 /* Set to a value that will kick off a read */
177 dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
178 /* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
179 * going to be way more than we need */
180 dev->blocks_in_checkpt = 0;
181 dev->checkpt_max_blocks =
182 (dev->internal_end_block - dev->internal_start_block) / 16 +
184 dev->checkpt_block_list =
185 kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
186 if (!dev->checkpt_block_list)
189 for (i = 0; i < dev->checkpt_max_blocks; i++)
190 dev->checkpt_block_list[i] = -1;
196 int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
199 composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
200 *sum = composite_sum;
204 static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
209 struct yaffs_ext_tags tags;
211 if (dev->checkpt_cur_block < 0) {
212 yaffs2_checkpt_find_erased_block(dev);
213 dev->checkpt_cur_chunk = 0;
216 if (dev->checkpt_cur_block < 0)
220 tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
221 tags.chunk_id = dev->checkpt_page_seq + 1;
222 tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
223 tags.n_bytes = dev->data_bytes_per_chunk;
224 if (dev->checkpt_cur_chunk == 0) {
225 /* First chunk we write for the block? Set block state to
227 struct yaffs_block_info *bi =
228 yaffs_get_block_info(dev, dev->checkpt_cur_block);
229 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
230 dev->blocks_in_checkpt++;
234 dev->checkpt_cur_block * dev->param.chunks_per_block +
235 dev->checkpt_cur_chunk;
237 T(YAFFS_TRACE_CHECKPOINT,
239 ("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
240 chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk, tags.obj_id,
243 realigned_chunk = chunk - dev->chunk_offset;
245 dev->n_page_writes++;
247 dev->param.write_chunk_tags_fn(dev, realigned_chunk,
248 dev->checkpt_buffer, &tags);
249 dev->checkpt_byte_offs = 0;
250 dev->checkpt_page_seq++;
251 dev->checkpt_cur_chunk++;
252 if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
253 dev->checkpt_cur_chunk = 0;
254 dev->checkpt_cur_block = -1;
256 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
261 int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
266 u8 *data_bytes = (u8 *) data;
268 if (!dev->checkpt_buffer)
271 if (!dev->checkpt_open_write)
274 while (i < n_bytes && ok) {
275 dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
276 dev->checkpt_sum += *data_bytes;
277 dev->checkpt_xor ^= *data_bytes;
279 dev->checkpt_byte_offs++;
282 dev->checkpt_byte_count++;
284 if (dev->checkpt_byte_offs < 0 ||
285 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
286 ok = yaffs2_checkpt_flush_buffer(dev);
292 int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
296 struct yaffs_ext_tags tags;
301 u8 *data_bytes = (u8 *) data;
303 if (!dev->checkpt_buffer)
306 if (dev->checkpt_open_write)
309 while (i < n_bytes && ok) {
311 if (dev->checkpt_byte_offs < 0 ||
312 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
314 if (dev->checkpt_cur_block < 0) {
315 yaffs2_checkpt_find_block(dev);
316 dev->checkpt_cur_chunk = 0;
319 if (dev->checkpt_cur_block < 0)
322 chunk = dev->checkpt_cur_block *
323 dev->param.chunks_per_block +
324 dev->checkpt_cur_chunk;
326 realigned_chunk = chunk - dev->chunk_offset;
330 /* read in the next chunk */
331 dev->param.read_chunk_tags_fn(dev,
337 if (tags.chunk_id != (dev->checkpt_page_seq + 1)
338 || tags.ecc_result > YAFFS_ECC_RESULT_FIXED
339 || tags.seq_number !=
340 YAFFS_SEQUENCE_CHECKPOINT_DATA)
343 dev->checkpt_byte_offs = 0;
344 dev->checkpt_page_seq++;
345 dev->checkpt_cur_chunk++;
347 if (dev->checkpt_cur_chunk >=
348 dev->param.chunks_per_block)
349 dev->checkpt_cur_block = -1;
355 dev->checkpt_buffer[dev->checkpt_byte_offs];
356 dev->checkpt_sum += *data_bytes;
357 dev->checkpt_xor ^= *data_bytes;
358 dev->checkpt_byte_offs++;
361 dev->checkpt_byte_count++;
368 int yaffs_checkpt_close(struct yaffs_dev *dev)
371 if (dev->checkpt_open_write) {
372 if (dev->checkpt_byte_offs != 0)
373 yaffs2_checkpt_flush_buffer(dev);
374 } else if (dev->checkpt_block_list) {
377 i < dev->blocks_in_checkpt
378 && dev->checkpt_block_list[i] >= 0; i++) {
379 int blk = dev->checkpt_block_list[i];
380 struct yaffs_block_info *bi = NULL;
381 if (dev->internal_start_block <= blk
382 && blk <= dev->internal_end_block)
383 bi = yaffs_get_block_info(dev, blk);
384 if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
385 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
387 /* Todo this looks odd... */
390 kfree(dev->checkpt_block_list);
391 dev->checkpt_block_list = NULL;
394 dev->n_free_chunks -=
395 dev->blocks_in_checkpt * dev->param.chunks_per_block;
396 dev->n_erased_blocks -= dev->blocks_in_checkpt;
398 T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
399 dev->checkpt_byte_count));
401 if (dev->checkpt_buffer) {
402 /* free the buffer */
403 kfree(dev->checkpt_buffer);
404 dev->checkpt_buffer = NULL;
411 int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
413 /* Erase the checkpoint data */
415 T(YAFFS_TRACE_CHECKPOINT,
416 (TSTR("checkpoint invalidate of %d blocks" TENDSTR),
417 dev->blocks_in_checkpt));
419 return yaffs_checkpt_erase(dev);