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 {
25 static int apply_chunk_offset(struct yaffs_dev *dev, int chunk)
27 return chunk - dev->chunk_offset;
30 static int apply_block_offset(struct yaffs_dev *dev, int block)
32 return block - dev->block_offset;
35 static void yaffs2_checkpt_init_chunk_hdr(struct yaffs_dev *dev)
37 struct yaffs_checkpt_chunk_hdr hdr;
39 hdr.version = YAFFS_CHECKPOINT_VERSION;
40 hdr.seq = dev->checkpt_page_seq;
41 hdr.sum = dev->checkpt_sum;
42 hdr.xor = dev->checkpt_xor;
44 dev->checkpt_byte_offs = sizeof(hdr);
46 memcpy(dev->checkpt_buffer, &hdr, sizeof(hdr));
49 static int yaffs2_checkpt_check_chunk_hdr(struct yaffs_dev *dev)
51 struct yaffs_checkpt_chunk_hdr hdr;
53 memcpy(&hdr, dev->checkpt_buffer, sizeof(hdr));
55 dev->checkpt_byte_offs = sizeof(hdr);
57 return hdr.version == YAFFS_CHECKPOINT_VERSION &&
58 hdr.seq == dev->checkpt_page_seq &&
59 hdr.sum == dev->checkpt_sum &&
60 hdr.xor == dev->checkpt_xor;
63 static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
65 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
67 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
68 "checkpt blocks_avail = %d", blocks_avail);
70 return (blocks_avail <= 0) ? 0 : 1;
73 static int yaffs_checkpt_erase(struct yaffs_dev *dev)
77 if (!dev->param.erase_fn)
79 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
80 "checking blocks %d to %d",
81 dev->internal_start_block, dev->internal_end_block);
83 for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
84 struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
85 int offset_i = apply_block_offset(dev, i);
88 if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
89 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
90 "erasing checkpt block %d", i);
94 result = dev->param.erase_fn(dev, offset_i);
96 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
97 dev->n_erased_blocks++;
99 dev->param.chunks_per_block;
101 dev->param.bad_block_fn(dev, offset_i);
102 bi->block_state = YAFFS_BLOCK_STATE_DEAD;
107 dev->blocks_in_checkpt = 0;
112 static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
115 int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
117 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
118 "allocating checkpt block: erased %d reserved %d avail %d next %d ",
119 dev->n_erased_blocks, dev->param.n_reserved_blocks,
120 blocks_avail, dev->checkpt_next_block);
122 if (dev->checkpt_next_block >= 0 &&
123 dev->checkpt_next_block <= dev->internal_end_block &&
126 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
128 struct yaffs_block_info *bi;
130 bi = yaffs_get_block_info(dev, i);
131 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
132 dev->checkpt_next_block = i + 1;
133 dev->checkpt_cur_block = i;
134 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
135 "allocating checkpt block %d", i);
140 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "out of checkpt blocks");
142 dev->checkpt_next_block = -1;
143 dev->checkpt_cur_block = -1;
146 static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
149 struct yaffs_ext_tags tags;
151 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
152 "find next checkpt block: start: blocks %d next %d",
153 dev->blocks_in_checkpt, dev->checkpt_next_block);
155 if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
156 for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
158 int chunk = i * dev->param.chunks_per_block;
159 enum yaffs_block_state state;
162 dev->param.read_chunk_tags_fn(dev,
163 apply_chunk_offset(dev, chunk),
165 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
166 "find next checkpt block: search: block %d state %d oid %d seq %d eccr %d",
168 tags.obj_id, tags.seq_number,
171 if (tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
174 dev->param.query_block_fn(dev,
175 apply_block_offset(dev, i),
177 if (state == YAFFS_BLOCK_STATE_DEAD)
180 /* Right kind of block */
181 dev->checkpt_next_block = tags.obj_id;
182 dev->checkpt_cur_block = i;
183 dev->checkpt_block_list[dev->blocks_in_checkpt] = i;
184 dev->blocks_in_checkpt++;
185 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
186 "found checkpt block %d", i);
190 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "found no more checkpt blocks");
192 dev->checkpt_next_block = -1;
193 dev->checkpt_cur_block = -1;
196 int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
200 dev->checkpt_open_write = writing;
202 /* Got the functions we need? */
203 if (!dev->param.write_chunk_tags_fn ||
204 !dev->param.read_chunk_tags_fn ||
205 !dev->param.erase_fn || !dev->param.bad_block_fn)
208 if (writing && !yaffs2_checkpt_space_ok(dev))
211 if (!dev->checkpt_buffer)
212 dev->checkpt_buffer =
213 kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
214 if (!dev->checkpt_buffer)
217 dev->checkpt_page_seq = 0;
218 dev->checkpt_byte_count = 0;
219 dev->checkpt_sum = 0;
220 dev->checkpt_xor = 0;
221 dev->checkpt_cur_block = -1;
222 dev->checkpt_cur_chunk = -1;
223 dev->checkpt_next_block = dev->internal_start_block;
226 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
227 yaffs2_checkpt_init_chunk_hdr(dev);
228 return yaffs_checkpt_erase(dev);
231 /* Opening for a read */
232 /* Set to a value that will kick off a read */
233 dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
234 /* A checkpoint block list of 1 checkpoint block per 16 block is
235 * (hopefully) going to be way more than we need */
236 dev->blocks_in_checkpt = 0;
237 dev->checkpt_max_blocks =
238 (dev->internal_end_block - dev->internal_start_block) / 16 + 2;
239 dev->checkpt_block_list =
240 kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
242 if (!dev->checkpt_block_list)
245 for (i = 0; i < dev->checkpt_max_blocks; i++)
246 dev->checkpt_block_list[i] = -1;
251 int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
255 composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
256 *sum = composite_sum;
260 static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
264 struct yaffs_ext_tags tags;
266 if (dev->checkpt_cur_block < 0) {
267 yaffs2_checkpt_find_erased_block(dev);
268 dev->checkpt_cur_chunk = 0;
271 if (dev->checkpt_cur_block < 0)
275 tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
276 tags.chunk_id = dev->checkpt_page_seq + 1;
277 tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
278 tags.n_bytes = dev->data_bytes_per_chunk;
279 if (dev->checkpt_cur_chunk == 0) {
280 /* First chunk we write for the block? Set block state to
282 struct yaffs_block_info *bi =
283 yaffs_get_block_info(dev, dev->checkpt_cur_block);
284 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
285 dev->blocks_in_checkpt++;
289 dev->checkpt_cur_block * dev->param.chunks_per_block +
290 dev->checkpt_cur_chunk;
292 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
293 "checkpoint wite buffer nand %d(%d:%d) objid %d chId %d",
294 chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk,
295 tags.obj_id, tags.chunk_id);
297 offset_chunk = apply_chunk_offset(dev, chunk);
299 dev->n_page_writes++;
301 dev->param.write_chunk_tags_fn(dev, offset_chunk,
302 dev->checkpt_buffer, &tags);
303 dev->checkpt_page_seq++;
304 dev->checkpt_cur_chunk++;
305 if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
306 dev->checkpt_cur_chunk = 0;
307 dev->checkpt_cur_block = -1;
309 memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
311 yaffs2_checkpt_init_chunk_hdr(dev);
317 int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
321 u8 *data_bytes = (u8 *) data;
323 if (!dev->checkpt_buffer)
326 if (!dev->checkpt_open_write)
329 while (i < n_bytes && ok) {
330 dev->checkpt_buffer[dev->checkpt_byte_offs] = *data_bytes;
331 dev->checkpt_sum += *data_bytes;
332 dev->checkpt_xor ^= *data_bytes;
334 dev->checkpt_byte_offs++;
337 dev->checkpt_byte_count++;
339 if (dev->checkpt_byte_offs < 0 ||
340 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
341 ok = yaffs2_checkpt_flush_buffer(dev);
347 int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
351 struct yaffs_ext_tags tags;
354 u8 *data_bytes = (u8 *) data;
356 if (!dev->checkpt_buffer)
359 if (dev->checkpt_open_write)
362 while (i < n_bytes && ok) {
364 if (dev->checkpt_byte_offs < 0 ||
365 dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
367 if (dev->checkpt_cur_block < 0) {
368 yaffs2_checkpt_find_block(dev);
369 dev->checkpt_cur_chunk = 0;
372 if (dev->checkpt_cur_block < 0) {
377 chunk = dev->checkpt_cur_block *
378 dev->param.chunks_per_block +
379 dev->checkpt_cur_chunk;
381 offset_chunk = apply_chunk_offset(dev, chunk);
384 /* read in the next chunk */
385 dev->param.read_chunk_tags_fn(dev,
390 if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
391 tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
392 tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA) {
396 if(!yaffs2_checkpt_check_chunk_hdr(dev)) {
401 dev->checkpt_page_seq++;
402 dev->checkpt_cur_chunk++;
404 if (dev->checkpt_cur_chunk >=
405 dev->param.chunks_per_block)
406 dev->checkpt_cur_block = -1;
410 *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
411 dev->checkpt_sum += *data_bytes;
412 dev->checkpt_xor ^= *data_bytes;
413 dev->checkpt_byte_offs++;
416 dev->checkpt_byte_count++;
422 int yaffs_checkpt_close(struct yaffs_dev *dev)
426 if (dev->checkpt_open_write) {
427 if (dev->checkpt_byte_offs !=
428 sizeof(sizeof(struct yaffs_checkpt_chunk_hdr)))
429 yaffs2_checkpt_flush_buffer(dev);
430 } else if (dev->checkpt_block_list) {
432 i < dev->blocks_in_checkpt &&
433 dev->checkpt_block_list[i] >= 0; i++) {
434 int blk = dev->checkpt_block_list[i];
435 struct yaffs_block_info *bi = NULL;
437 if (dev->internal_start_block <= blk &&
438 blk <= dev->internal_end_block)
439 bi = yaffs_get_block_info(dev, blk);
440 if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
441 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
443 kfree(dev->checkpt_block_list);
444 dev->checkpt_block_list = NULL;
447 dev->n_free_chunks -=
448 dev->blocks_in_checkpt * dev->param.chunks_per_block;
449 dev->n_erased_blocks -= dev->blocks_in_checkpt;
451 yaffs_trace(YAFFS_TRACE_CHECKPOINT, "checkpoint byte count %d",
452 dev->checkpt_byte_count);
454 if (dev->checkpt_buffer) {
455 /* free the buffer */
456 kfree(dev->checkpt_buffer);
457 dev->checkpt_buffer = NULL;
464 int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
466 /* Erase the checkpoint data */
468 yaffs_trace(YAFFS_TRACE_CHECKPOINT,
469 "checkpoint invalidate of %d blocks",
470 dev->blocks_in_checkpt);
472 return yaffs_checkpt_erase(dev);