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"
17 struct yaffs_checkpt_chunk_hdr {
24 static void yaffs2_checkpt_init_chunk_hdr(struct yaffs_dev *dev)
26 struct yaffs_checkpt_chunk_hdr hdr;
28 hdr.version = YAFFS_CHECKPOINT_VERSION;
29 hdr.seq = dev->checkpt_page_seq;
30 hdr.sum = dev->checkpt_sum;
31 hdr.xor = dev->checkpt_xor;
33 dev->checkpt_byte_offs = sizeof(hdr);
35 memcpy(dev->checkpt_buffer, &hdr, sizeof(hdr));
38 static int yaffs2_checkpt_check_chunk_hdr(struct yaffs_dev *dev)
40 struct yaffs_checkpt_chunk_hdr hdr;
42 memcpy(&hdr, dev->checkpt_buffer, sizeof(hdr));
44 dev->checkpt_byte_offs = sizeof(hdr);
46 return hdr.version == YAFFS_CHECKPOINT_VERSION &&
47 hdr.seq == dev->checkpt_page_seq &&
48 hdr.sum == dev->checkpt_sum &&
49 hdr.xor == dev->checkpt_xor;
52 static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
54 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
56 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
57 "checkpt blocks_avail = %d", blocks_avail);
59 return (blocks_avail <= 0) ? 0 : 1;
62 static int yaffs_checkpt_erase(struct yaffs_dev *dev)
66 if (!dev->param.erase_fn)
68 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
69 "checking blocks %d to %d",
70 dev->internal_start_block, dev->internal_end_block);
72 for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
73 struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
74 if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
75 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
76 "erasing checkpt block %d", i);
82 i - dev->block_offset /* realign */)) {
83 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
84 dev->n_erased_blocks++;
86 dev->param.chunks_per_block;
88 dev->param.bad_block_fn(dev, i);
89 bi->block_state = YAFFS_BLOCK_STATE_DEAD;
94 dev->blocks_in_checkpt = 0;
99 static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
102 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
104 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
105 "allocating checkpt block: erased %d reserved %d avail %d next %d ",
106 dev->n_erased_blocks, dev->param.n_reserved_blocks,
107 blocks_avail, dev->checkpt_next_block);
109 if (dev->checkpt_next_block >= 0 &&
110 dev->checkpt_next_block <= dev->internal_end_block &&
113 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
115 struct yaffs_block_info *bi =
116 yaffs_get_block_info(dev, i);
117 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
118 dev->checkpt_next_block = i + 1;
119 dev->checkpt_cur_block = i;
120 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
121 "allocating checkpt block %d", i);
126 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "out of checkpt blocks");
128 dev->checkpt_next_block = -1;
129 dev->checkpt_cur_block = -1;
132 static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
135 struct yaffs_ext_tags tags;
137 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
138 "find next checkpt block: start: blocks %d next %d",
139 dev->blocks_in_checkpt, dev->checkpt_next_block);
141 if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
142 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
144 int chunk = i * dev->param.chunks_per_block;
145 int realigned_chunk = chunk - dev->chunk_offset;
146 enum yaffs_block_state state;
149 dev->param.read_chunk_tags_fn(dev, realigned_chunk,
151 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
152 "find next checkpt block: search: block %d state %d oid %d seq %d eccr %d",
154 tags.obj_id, tags.seq_number,
157 if (tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
160 dev->param.query_block_fn(dev, i, &state, &seq);
161 if (state == YAFFS_BLOCK_STATE_DEAD)
164 /* Right kind of block */
165 dev->checkpt_next_block = tags.obj_id;
166 dev->checkpt_cur_block = i;
167 dev->checkpt_block_list[dev->blocks_in_checkpt] = i;
168 dev->blocks_in_checkpt++;
169 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
170 "found checkpt block %d", i);
174 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "found no more checkpt blocks");
176 dev->checkpt_next_block = -1;
177 dev->checkpt_cur_block = -1;
180 int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
184 dev->checkpt_open_write = writing;
186 /* Got the functions we need? */
187 if (!dev->param.write_chunk_tags_fn ||
188 !dev->param.read_chunk_tags_fn ||
189 !dev->param.erase_fn || !dev->param.bad_block_fn)
192 if (writing && !yaffs2_checkpt_space_ok(dev))
195 if (!dev->checkpt_buffer)
196 dev->checkpt_buffer =
197 kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
198 if (!dev->checkpt_buffer)
201 dev->checkpt_page_seq = 0;
202 dev->checkpt_byte_count = 0;
203 dev->checkpt_sum = 0;
204 dev->checkpt_xor = 0;
205 dev->checkpt_cur_block = -1;
206 dev->checkpt_cur_chunk = -1;
207 dev->checkpt_next_block = dev->internal_start_block;
210 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
211 yaffs2_checkpt_init_chunk_hdr(dev);
212 return yaffs_checkpt_erase(dev);
215 /* Opening for a read */
216 /* Set to a value that will kick off a read */
217 dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
218 /* A checkpoint block list of 1 checkpoint block per 16 block is
219 * (hopefully) going to be way more than we need */
220 dev->blocks_in_checkpt = 0;
221 dev->checkpt_max_blocks =
222 (dev->internal_end_block - dev->internal_start_block) / 16 + 2;
223 dev->checkpt_block_list =
224 kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
226 if (!dev->checkpt_block_list)
229 for (i = 0; i < dev->checkpt_max_blocks; i++)
230 dev->checkpt_block_list[i] = -1;
235 int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
239 composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
240 *sum = composite_sum;
244 static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
248 struct yaffs_ext_tags tags;
250 if (dev->checkpt_cur_block < 0) {
251 yaffs2_checkpt_find_erased_block(dev);
252 dev->checkpt_cur_chunk = 0;
255 if (dev->checkpt_cur_block < 0)
259 tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
260 tags.chunk_id = dev->checkpt_page_seq + 1;
261 tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
262 tags.n_bytes = dev->data_bytes_per_chunk;
263 if (dev->checkpt_cur_chunk == 0) {
264 /* First chunk we write for the block? Set block state to
266 struct yaffs_block_info *bi =
267 yaffs_get_block_info(dev, dev->checkpt_cur_block);
268 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
269 dev->blocks_in_checkpt++;
273 dev->checkpt_cur_block * dev->param.chunks_per_block +
274 dev->checkpt_cur_chunk;
276 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
277 "checkpoint wite buffer nand %d(%d:%d) objid %d chId %d",
278 chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk,
279 tags.obj_id, tags.chunk_id);
281 realigned_chunk = chunk - dev->chunk_offset;
283 dev->n_page_writes++;
285 dev->param.write_chunk_tags_fn(dev, realigned_chunk,
286 dev->checkpt_buffer, &tags);
287 dev->checkpt_page_seq++;
288 dev->checkpt_cur_chunk++;
289 if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
290 dev->checkpt_cur_chunk = 0;
291 dev->checkpt_cur_block = -1;
293 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
295 yaffs2_checkpt_init_chunk_hdr(dev);
301 int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
305 u8 *data_bytes = (u8 *) data;
307 if (!dev->checkpt_buffer)
310 if (!dev->checkpt_open_write)
313 while (i < n_bytes && ok) {
314 dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
315 dev->checkpt_sum += *data_bytes;
316 dev->checkpt_xor ^= *data_bytes;
318 dev->checkpt_byte_offs++;
321 dev->checkpt_byte_count++;
323 if (dev->checkpt_byte_offs < 0 ||
324 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
325 ok = yaffs2_checkpt_flush_buffer(dev);
331 int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
335 struct yaffs_ext_tags tags;
338 u8 *data_bytes = (u8 *) data;
340 if (!dev->checkpt_buffer)
343 if (dev->checkpt_open_write)
346 while (i < n_bytes && ok) {
348 if (dev->checkpt_byte_offs < 0 ||
349 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
351 if (dev->checkpt_cur_block < 0) {
352 yaffs2_checkpt_find_block(dev);
353 dev->checkpt_cur_chunk = 0;
356 if (dev->checkpt_cur_block < 0) {
361 chunk = dev->checkpt_cur_block *
362 dev->param.chunks_per_block +
363 dev->checkpt_cur_chunk;
365 realigned_chunk = chunk - dev->chunk_offset;
368 /* read in the next chunk */
369 dev->param.read_chunk_tags_fn(dev,
374 if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
375 tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
376 tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA) {
380 if(!yaffs2_checkpt_check_chunk_hdr(dev)) {
385 dev->checkpt_page_seq++;
386 dev->checkpt_cur_chunk++;
388 if (dev->checkpt_cur_chunk >=
389 dev->param.chunks_per_block)
390 dev->checkpt_cur_block = -1;
394 *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
395 dev->checkpt_sum += *data_bytes;
396 dev->checkpt_xor ^= *data_bytes;
397 dev->checkpt_byte_offs++;
400 dev->checkpt_byte_count++;
406 int yaffs_checkpt_close(struct yaffs_dev *dev)
410 if (dev->checkpt_open_write) {
411 if (dev->checkpt_byte_offs !=
412 sizeof(sizeof(struct yaffs_checkpt_chunk_hdr)))
413 yaffs2_checkpt_flush_buffer(dev);
414 } else if (dev->checkpt_block_list) {
416 i < dev->blocks_in_checkpt &&
417 dev->checkpt_block_list[i] >= 0; i++) {
418 int blk = dev->checkpt_block_list[i];
419 struct yaffs_block_info *bi = NULL;
421 if (dev->internal_start_block <= blk &&
422 blk <= dev->internal_end_block)
423 bi = yaffs_get_block_info(dev, blk);
424 if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
425 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
427 kfree(dev->checkpt_block_list);
428 dev->checkpt_block_list = NULL;
431 dev->n_free_chunks -=
432 dev->blocks_in_checkpt * dev->param.chunks_per_block;
433 dev->n_erased_blocks -= dev->blocks_in_checkpt;
435 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "checkpoint byte count %d",
436 dev->checkpt_byte_count);
438 if (dev->checkpt_buffer) {
439 /* free the buffer */
440 kfree(dev->checkpt_buffer);
441 dev->checkpt_buffer = NULL;
448 int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
450 /* Erase the checkpoint data */
452 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
453 "checkpoint invalidate of %d blocks",
454 dev->blocks_in_checkpt);
456 return yaffs_checkpt_erase(dev);