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Diffstat (limited to 'target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c')
-rw-r--r--target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c466
1 files changed, 466 insertions, 0 deletions
diff --git a/target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c b/target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 0000000..16ee1e0
--- /dev/null
+++ b/target/linux/generic/files/fs/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,466 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2011 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"
+
+struct yaffs_checkpt_chunk_hdr {
+ int version;
+ int seq;
+ u32 sum;
+ u32 xor;
+} ;
+
+
+static int apply_chunk_offset(struct yaffs_dev *dev, int chunk)
+{
+ return chunk - dev->chunk_offset;
+}
+
+static int apply_block_offset(struct yaffs_dev *dev, int block)
+{
+ return block - dev->block_offset;
+}
+
+static void yaffs2_checkpt_init_chunk_hdr(struct yaffs_dev *dev)
+{
+ struct yaffs_checkpt_chunk_hdr hdr;
+
+ hdr.version = YAFFS_CHECKPOINT_VERSION;
+ hdr.seq = dev->checkpt_page_seq;
+ hdr.sum = dev->checkpt_sum;
+ hdr.xor = dev->checkpt_xor;
+
+ dev->checkpt_byte_offs = sizeof(hdr);
+
+ memcpy(dev->checkpt_buffer, &hdr, sizeof(hdr));
+}
+
+static int yaffs2_checkpt_check_chunk_hdr(struct yaffs_dev *dev)
+{
+ struct yaffs_checkpt_chunk_hdr hdr;
+
+ memcpy(&hdr, dev->checkpt_buffer, sizeof(hdr));
+
+ dev->checkpt_byte_offs = sizeof(hdr);
+
+ return hdr.version == YAFFS_CHECKPOINT_VERSION &&
+ hdr.seq == dev->checkpt_page_seq &&
+ hdr.sum == dev->checkpt_sum &&
+ hdr.xor == dev->checkpt_xor;
+}
+
+static int yaffs2_checkpt_space_ok(struct yaffs_dev *dev)
+{
+ int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "checkpt blocks_avail = %d", blocks_avail);
+
+ return (blocks_avail <= 0) ? 0 : 1;
+}
+
+static int yaffs_checkpt_erase(struct yaffs_dev *dev)
+{
+ int i;
+
+ if (!dev->drv.drv_erase_fn)
+ return 0;
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "checking blocks %d to %d",
+ dev->internal_start_block, dev->internal_end_block);
+
+ for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
+ struct yaffs_block_info *bi = yaffs_get_block_info(dev, i);
+ int offset_i = apply_block_offset(dev, i);
+ int result;
+
+ if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "erasing checkpt block %d", i);
+
+ dev->n_erasures++;
+
+ result = dev->drv.drv_erase_fn(dev, offset_i);
+ if(result) {
+ bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
+ dev->n_erased_blocks++;
+ dev->n_free_chunks +=
+ dev->param.chunks_per_block;
+ } else {
+ dev->drv.drv_mark_bad_fn(dev, offset_i);
+ bi->block_state = YAFFS_BLOCK_STATE_DEAD;
+ }
+ }
+ }
+
+ dev->blocks_in_checkpt = 0;
+
+ return 1;
+}
+
+static void yaffs2_checkpt_find_erased_block(struct yaffs_dev *dev)
+{
+ int i;
+ int blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "allocating checkpt block: erased %d reserved %d avail %d next %d ",
+ dev->n_erased_blocks, dev->param.n_reserved_blocks,
+ blocks_avail, dev->checkpt_next_block);
+
+ if (dev->checkpt_next_block >= 0 &&
+ dev->checkpt_next_block <= dev->internal_end_block &&
+ blocks_avail > 0) {
+
+ for (i = dev->checkpt_next_block; i <= dev->internal_end_block;
+ i++) {
+ struct yaffs_block_info *bi;
+
+ 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;
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "allocating checkpt block %d", i);
+ return;
+ }
+ }
+ }
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT, "out of checkpt blocks");
+
+ dev->checkpt_next_block = -1;
+ dev->checkpt_cur_block = -1;
+}
+
+static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
+{
+ int i;
+ struct yaffs_ext_tags tags;
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "find next checkpt block: start: blocks %d next %d",
+ 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;
+ enum yaffs_block_state state;
+ u32 seq;
+
+ dev->tagger.read_chunk_tags_fn(dev,
+ apply_chunk_offset(dev, chunk),
+ NULL, &tags);
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "find next checkpt block: search: block %d state %d oid %d seq %d eccr %d",
+ i, (int) state,
+ tags.obj_id, tags.seq_number,
+ tags.ecc_result);
+
+ if (tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
+ continue;
+
+ dev->tagger.query_block_fn(dev,
+ apply_block_offset(dev, i),
+ &state, &seq);
+ if (state == YAFFS_BLOCK_STATE_DEAD)
+ continue;
+
+ /* 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++;
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "found checkpt block %d", i);
+ return;
+ }
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT, "found no more checkpt blocks");
+
+ dev->checkpt_next_block = -1;
+ dev->checkpt_cur_block = -1;
+}
+
+int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
+{
+ int i;
+
+ dev->checkpt_open_write = writing;
+
+ /* Got the functions we need? */
+ if (!dev->tagger.write_chunk_tags_fn ||
+ !dev->tagger.read_chunk_tags_fn ||
+ !dev->drv.drv_erase_fn ||
+ !dev->drv.drv_mark_bad_fn)
+ return 0;
+
+ if (writing && !yaffs2_checkpt_space_ok(dev))
+ return 0;
+
+ if (!dev->checkpt_buffer)
+ dev->checkpt_buffer =
+ kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
+ 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;
+
+ if (writing) {
+ memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
+ yaffs2_checkpt_init_chunk_hdr(dev);
+ return yaffs_checkpt_erase(dev);
+ }
+
+ /* Opening for a read */
+ /* 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;
+ if (!dev->checkpt_block_list)
+ dev->checkpt_block_list =
+ kmalloc(sizeof(int) * dev->checkpt_max_blocks, GFP_NOFS);
+
+ 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(struct yaffs_dev *dev, u32 * sum)
+{
+ u32 composite_sum;
+
+ composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
+ *sum = composite_sum;
+ return 1;
+}
+
+static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
+{
+ int chunk;
+ int offset_chunk;
+ struct 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 */
+ struct yaffs_block_info *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;
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "checkpoint wite buffer nand %d(%d:%d) objid %d chId %d",
+ chunk, dev->checkpt_cur_block, dev->checkpt_cur_chunk,
+ tags.obj_id, tags.chunk_id);
+
+ offset_chunk = apply_chunk_offset(dev, chunk);
+
+ dev->n_page_writes++;
+
+ dev->tagger.write_chunk_tags_fn(dev, offset_chunk,
+ dev->checkpt_buffer, &tags);
+ 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);
+
+ yaffs2_checkpt_init_chunk_hdr(dev);
+
+
+ return 1;
+}
+
+int yaffs2_checkpt_wr(struct yaffs_dev *dev, const void *data, int n_bytes)
+{
+ int i = 0;
+ int ok = 1;
+ u8 *data_bytes = (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] = *data_bytes;
+ dev->checkpt_sum += *data_bytes;
+ dev->checkpt_xor ^= *data_bytes;
+
+ dev->checkpt_byte_offs++;
+ i++;
+ data_bytes++;
+ 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(struct yaffs_dev *dev, void *data, int n_bytes)
+{
+ int i = 0;
+ struct yaffs_ext_tags tags;
+ int chunk;
+ int offset_chunk;
+ u8 *data_bytes = (u8 *) data;
+
+ if (!dev->checkpt_buffer)
+ return 0;
+
+ if (dev->checkpt_open_write)
+ return -1;
+
+ while (i < n_bytes) {
+
+ 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;
+ }
+
+ /* Bail out if we can't find a checpoint block */
+ if (dev->checkpt_cur_block < 0)
+ break;
+
+ chunk = dev->checkpt_cur_block *
+ dev->param.chunks_per_block +
+ dev->checkpt_cur_chunk;
+
+ offset_chunk = apply_chunk_offset(dev, chunk);
+ dev->n_page_reads++;
+
+ /* Read in the next chunk */
+ dev->tagger.read_chunk_tags_fn(dev,
+ offset_chunk,
+ dev->checkpt_buffer,
+ &tags);
+
+ /* Bail out if the chunk is corrupted. */
+ if (tags.chunk_id != (dev->checkpt_page_seq + 1) ||
+ tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
+ tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
+ break;
+
+ /* Bail out if it is not a checkpoint chunk. */
+ if(!yaffs2_checkpt_check_chunk_hdr(dev))
+ break;
+
+ dev->checkpt_page_seq++;
+ dev->checkpt_cur_chunk++;
+
+ if (dev->checkpt_cur_chunk >=
+ dev->param.chunks_per_block)
+ dev->checkpt_cur_block = -1;
+
+ }
+
+ *data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
+ dev->checkpt_sum += *data_bytes;
+ dev->checkpt_xor ^= *data_bytes;
+ dev->checkpt_byte_offs++;
+ i++;
+ data_bytes++;
+ dev->checkpt_byte_count++;
+ }
+
+ return i; /* Number of bytes read */
+}
+
+int yaffs_checkpt_close(struct yaffs_dev *dev)
+{
+ int i;
+
+ if (dev->checkpt_open_write) {
+ if (dev->checkpt_byte_offs !=
+ sizeof(sizeof(struct yaffs_checkpt_chunk_hdr)))
+ yaffs2_checkpt_flush_buffer(dev);
+ } else if (dev->checkpt_block_list) {
+ for (i = 0;
+ i < dev->blocks_in_checkpt &&
+ dev->checkpt_block_list[i] >= 0; i++) {
+ int blk = dev->checkpt_block_list[i];
+ struct yaffs_block_info *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;
+ }
+ }
+
+ dev->n_free_chunks -=
+ dev->blocks_in_checkpt * dev->param.chunks_per_block;
+ dev->n_erased_blocks -= dev->blocks_in_checkpt;
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT, "checkpoint byte count %d",
+ dev->checkpt_byte_count);
+
+ if (dev->checkpt_buffer)
+ return 1;
+ else
+ return 0;
+}
+
+int yaffs2_checkpt_invalidate_stream(struct yaffs_dev *dev)
+{
+ /* Erase the checkpoint data */
+
+ yaffs_trace(YAFFS_TRACE_CHECKPOINT,
+ "checkpoint invalidate of %d blocks",
+ dev->blocks_in_checkpt);
+
+ return yaffs_checkpt_erase(dev);
+}