[PATCH 07/29] Staging: yaffs2: yaffs_checkptrw: Add files

[Tracey Dent <tdent48227@gmail.com>]

Adding files to yaffs2 directory.

Signed-off-by: Tracey Dent <tdent48227@gmail.com>
---
 drivers/staging/yaffs2/yaffs_checkptrw.c |  400 ++++++++++++++++++++++++++++++
 drivers/staging/yaffs2/yaffs_checkptrw.h |   34 +++
 2 files changed, 434 insertions(+), 0 deletions(-)
 create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.c
 create mode 100644 drivers/staging/yaffs2/yaffs_checkptrw.h

diff --git a/drivers/staging/yaffs2/yaffs_checkptrw.c b/drivers/staging/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 0000000..82d6874
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,400 @@
+/*
+ * 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 blocks_avail = dev->n_erased_blocks - dev->param.n_reserved_blocks;
+
+	T(YAFFS_TRACE_CHECKPOINT,
+		(TSTR("checkpt blocks available = %d" TENDSTR),
+		blocks_avail));
+
+	return (blocks_avail <= 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 blocks_avail = 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, 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++) {
+			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 realigned_chunk = chunk - dev->chunk_offset;
+
+			dev->param.read_chunk_tags_fn(dev, realigned_chunk,
+					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 writing)
+{
+
+
+	dev->checkpt_open_write = writing;
+
+	/* 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 (writing && !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 (writing) {
+		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 composite_sum;
+	composite_sum =  (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
+	*sum = composite_sum;
+	return 1;
+}
+
+static int yaffs2_checkpt_flush_buffer(yaffs_dev_t *dev)
+{
+	int chunk;
+	int realigned_chunk;
+
+	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));
+
+	realigned_chunk = chunk - dev->chunk_offset;
+
+	dev->n_page_writes++;
+
+	dev->param.write_chunk_tags_fn(dev, realigned_chunk,
+			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 * 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(yaffs_dev_t *dev, void *data, int n_bytes)
+{
+	int i = 0;
+	int ok = 1;
+	yaffs_ext_tags tags;
+
+
+	int chunk;
+	int realigned_chunk;
+
+	__u8 *data_bytes = (__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;
+
+				realigned_chunk = chunk - dev->chunk_offset;
+				
+				dev->n_page_reads++;
+
+				/* read in the next chunk */
+				dev->param.read_chunk_tags_fn(dev,
+						realigned_chunk,
+						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) {
+			*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;
+}
+
+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);
+}
+
+
+
diff --git a/drivers/staging/yaffs2/yaffs_checkptrw.h b/drivers/staging/yaffs2/yaffs_checkptrw.h
new file mode 100644
index 0000000..582b89c
--- /dev/null
+++ b/drivers/staging/yaffs2/yaffs_checkptrw.h
@@ -0,0 +1,34 @@
+/*
+ * 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 Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CHECKPTRW_H__
+#define __YAFFS_CHECKPTRW_H__
+
+#include "yaffs_guts.h"
+
+int yaffs2_checkpt_open(yaffs_dev_t *dev, int writing);
+
+int yaffs2_checkpt_wr(yaffs_dev_t *dev, const void *data, int n_bytes);
+
+int yaffs2_checkpt_rd(yaffs_dev_t *dev, void *data, int n_bytes);
+
+int yaffs2_get_checkpt_sum(yaffs_dev_t *dev, __u32 *sum);
+
+int yaffs_checkpt_close(yaffs_dev_t *dev);
+
+int yaffs2_checkpt_invalidate_stream(yaffs_dev_t *dev);
+
+
+#endif
-- 
1.7.3.2.146.gca209