blob: d46f5634ac1f269b29defaf7a58790a0645087bd [file] [log] [blame]
/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2010 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <charles@aleph1.co.uk>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include "yaffs_checkptrw.h"
#include "yaffs_getblockinfo.h"
static int yaffs2_checkpt_space_ok(yaffs_dev_t *dev)
{
int blocksAvailable = dev->n_erased_blocks - dev->param.n_reserved_blocks;
T(YAFFS_TRACE_CHECKPOINT,
(TSTR("checkpt blocks available = %d" TENDSTR),
blocksAvailable));
return (blocksAvailable <= 0) ? 0 : 1;
}
static int yaffs_checkpt_erase(yaffs_dev_t *dev)
{
int i;
if (!dev->param.erase_fn)
return 0;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d"TENDSTR),
dev->internal_start_block, dev->internal_end_block));
for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
yaffs_block_info_t *bi = yaffs_get_block_info(dev, i);
if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
T(YAFFS_TRACE_CHECKPOINT, (TSTR("erasing checkpt block %d"TENDSTR), i));
dev->n_erasures++;
if (dev->param.erase_fn(dev, i - dev->block_offset /* realign */)) {
bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
dev->n_erased_blocks++;
dev->n_free_chunks += dev->param.chunks_per_block;
} else {
dev->param.bad_block_fn(dev, i);
bi->block_state = YAFFS_BLOCK_STATE_DEAD;
}
}
}
dev->blocks_in_checkpt = 0;
return 1;
}
static void yaffs2_checkpt_find_erased_block(yaffs_dev_t *dev)
{
int i;
int blocksAvailable = dev->n_erased_blocks - dev->param.n_reserved_blocks;
T(YAFFS_TRACE_CHECKPOINT,
(TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
dev->n_erased_blocks, dev->param.n_reserved_blocks, blocksAvailable, dev->checkpt_next_block));
if (dev->checkpt_next_block >= 0 &&
dev->checkpt_next_block <= dev->internal_end_block &&
blocksAvailable > 0) {
for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {
yaffs_block_info_t *bi = yaffs_get_block_info(dev, i);
if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
dev->checkpt_next_block = i + 1;
dev->checkpt_cur_block = i;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("allocating checkpt block %d"TENDSTR), i));
return;
}
}
}
T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks"TENDSTR)));
dev->checkpt_next_block = -1;
dev->checkpt_cur_block = -1;
}
static void yaffs2_checkpt_find_block(yaffs_dev_t *dev)
{
int i;
yaffs_ext_tags tags;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start: blocks %d next %d" TENDSTR),
dev->blocks_in_checkpt, dev->checkpt_next_block));
if (dev->blocks_in_checkpt < dev->checkpt_max_blocks)
for (i = dev->checkpt_next_block; i <= dev->internal_end_block; i++) {
int chunk = i * dev->param.chunks_per_block;
int realignedChunk = chunk - dev->chunk_offset;
dev->param.read_chunk_tags_fn(dev, realignedChunk,
NULL, &tags);
T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
i, tags.obj_id, tags.seq_number, tags.ecc_result));
if (tags.seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
/* Right kind of block */
dev->checkpt_next_block = tags.obj_id;
dev->checkpt_cur_block = i;
dev->checkpt_block_list[dev->blocks_in_checkpt] = i;
dev->blocks_in_checkpt++;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("found checkpt block %d"TENDSTR), i));
return;
}
}
T(YAFFS_TRACE_CHECKPOINT, (TSTR("found no more checkpt blocks"TENDSTR)));
dev->checkpt_next_block = -1;
dev->checkpt_cur_block = -1;
}
int yaffs2_checkpt_open(yaffs_dev_t *dev, int forWriting)
{
dev->checkpt_open_write = forWriting;
/* Got the functions we need? */
if (!dev->param.write_chunk_tags_fn ||
!dev->param.read_chunk_tags_fn ||
!dev->param.erase_fn ||
!dev->param.bad_block_fn)
return 0;
if (forWriting && !yaffs2_checkpt_space_ok(dev))
return 0;
if (!dev->checkpt_buffer)
dev->checkpt_buffer = YMALLOC_DMA(dev->param.total_bytes_per_chunk);
if (!dev->checkpt_buffer)
return 0;
dev->checkpt_page_seq = 0;
dev->checkpt_byte_count = 0;
dev->checkpt_sum = 0;
dev->checkpt_xor = 0;
dev->checkpt_cur_block = -1;
dev->checkpt_cur_chunk = -1;
dev->checkpt_next_block = dev->internal_start_block;
/* Erase all the blocks in the checkpoint area */
if (forWriting) {
memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
dev->checkpt_byte_offs = 0;
return yaffs_checkpt_erase(dev);
} else {
int i;
/* Set to a value that will kick off a read */
dev->checkpt_byte_offs = dev->data_bytes_per_chunk;
/* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
* going to be way more than we need */
dev->blocks_in_checkpt = 0;
dev->checkpt_max_blocks = (dev->internal_end_block - dev->internal_start_block)/16 + 2;
dev->checkpt_block_list = YMALLOC(sizeof(int) * dev->checkpt_max_blocks);
if(!dev->checkpt_block_list)
return 0;
for (i = 0; i < dev->checkpt_max_blocks; i++)
dev->checkpt_block_list[i] = -1;
}
return 1;
}
int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum)
{
__u32 compositeSum;
compositeSum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
*sum = compositeSum;
return 1;
}
static int yaffs2_checkpt_flush_buffer(yaffs_dev_t *dev)
{
int chunk;
int realignedChunk;
yaffs_ext_tags tags;
if (dev->checkpt_cur_block < 0) {
yaffs2_checkpt_find_erased_block(dev);
dev->checkpt_cur_chunk = 0;
}
if (dev->checkpt_cur_block < 0)
return 0;
tags.is_deleted = 0;
tags.obj_id = dev->checkpt_next_block; /* Hint to next place to look */
tags.chunk_id = dev->checkpt_page_seq + 1;
tags.seq_number = YAFFS_SEQUENCE_CHECKPOINT_DATA;
tags.n_bytes = dev->data_bytes_per_chunk;
if (dev->checkpt_cur_chunk == 0) {
/* First chunk we write for the block? Set block state to
checkpoint */
yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->checkpt_cur_block);
bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
dev->blocks_in_checkpt++;
}
chunk = dev->checkpt_cur_block * dev->param.chunks_per_block + dev->checkpt_cur_chunk;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk, tags.obj_id, tags.chunk_id));
realignedChunk = chunk - dev->chunk_offset;
dev->n_page_writes++;
dev->param.write_chunk_tags_fn(dev, realignedChunk,
dev->checkpt_buffer, &tags);
dev->checkpt_byte_offs = 0;
dev->checkpt_page_seq++;
dev->checkpt_cur_chunk++;
if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block) {
dev->checkpt_cur_chunk = 0;
dev->checkpt_cur_block = -1;
}
memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
return 1;
}
int yaffs2_checkpt_wr(yaffs_dev_t *dev, const void *data, int n_bytes)
{
int i = 0;
int ok = 1;
__u8 * dataBytes = (__u8 *)data;
if (!dev->checkpt_buffer)
return 0;
if (!dev->checkpt_open_write)
return -1;
while (i < n_bytes && ok) {
dev->checkpt_buffer[dev->checkpt_byte_offs] = *dataBytes;
dev->checkpt_sum += *dataBytes;
dev->checkpt_xor ^= *dataBytes;
dev->checkpt_byte_offs++;
i++;
dataBytes++;
dev->checkpt_byte_count++;
if (dev->checkpt_byte_offs < 0 ||
dev->checkpt_byte_offs >= dev->data_bytes_per_chunk)
ok = yaffs2_checkpt_flush_buffer(dev);
}
return i;
}
int yaffs2_checkpt_rd(yaffs_dev_t *dev, void *data, int n_bytes)
{
int i = 0;
int ok = 1;
yaffs_ext_tags tags;
int chunk;
int realignedChunk;
__u8 *dataBytes = (__u8 *)data;
if (!dev->checkpt_buffer)
return 0;
if (dev->checkpt_open_write)
return -1;
while (i < n_bytes && ok) {
if (dev->checkpt_byte_offs < 0 ||
dev->checkpt_byte_offs >= dev->data_bytes_per_chunk) {
if (dev->checkpt_cur_block < 0) {
yaffs2_checkpt_find_block(dev);
dev->checkpt_cur_chunk = 0;
}
if (dev->checkpt_cur_block < 0)
ok = 0;
else {
chunk = dev->checkpt_cur_block *
dev->param.chunks_per_block +
dev->checkpt_cur_chunk;
realignedChunk = chunk - dev->chunk_offset;
dev->n_page_reads++;
/* read in the next chunk */
/* printf("read checkpoint page %d\n",dev->checkpointPage); */
dev->param.read_chunk_tags_fn(dev,
realignedChunk,
dev->checkpt_buffer,
&tags);
if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
ok = 0;
dev->checkpt_byte_offs = 0;
dev->checkpt_page_seq++;
dev->checkpt_cur_chunk++;
if (dev->checkpt_cur_chunk >= dev->param.chunks_per_block)
dev->checkpt_cur_block = -1;
}
}
if (ok) {
*dataBytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
dev->checkpt_sum += *dataBytes;
dev->checkpt_xor ^= *dataBytes;
dev->checkpt_byte_offs++;
i++;
dataBytes++;
dev->checkpt_byte_count++;
}
}
return i;
}
int yaffs_checkpt_close(yaffs_dev_t *dev)
{
if (dev->checkpt_open_write) {
if (dev->checkpt_byte_offs != 0)
yaffs2_checkpt_flush_buffer(dev);
} else if(dev->checkpt_block_list){
int i;
for (i = 0; i < dev->blocks_in_checkpt && dev->checkpt_block_list[i] >= 0; i++) {
int blk = dev->checkpt_block_list[i];
yaffs_block_info_t *bi = NULL;
if( dev->internal_start_block <= blk && blk <= dev->internal_end_block)
bi = yaffs_get_block_info(dev, blk);
if (bi && bi->block_state == YAFFS_BLOCK_STATE_EMPTY)
bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT;
else {
/* Todo this looks odd... */
}
}
YFREE(dev->checkpt_block_list);
dev->checkpt_block_list = NULL;
}
dev->n_free_chunks -= dev->blocks_in_checkpt * dev->param.chunks_per_block;
dev->n_erased_blocks -= dev->blocks_in_checkpt;
T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
dev->checkpt_byte_count));
if (dev->checkpt_buffer) {
/* free the buffer */
YFREE(dev->checkpt_buffer);
dev->checkpt_buffer = NULL;
return 1;
} else
return 0;
}
int yaffs2_checkpt_invalidate_stream(yaffs_dev_t *dev)
{
/* Erase the checkpoint data */
T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint invalidate of %d blocks"TENDSTR),
dev->blocks_in_checkpt));
return yaffs_checkpt_erase(dev);
}