X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=yaffs_checkptrw.c;h=d8970449b04812de994f85737f749fe6120c0e7b;hp=7faf2860f923775952300824a34562d152641ad7;hb=cb185cec287359727e44321979ad2324b4fad7cb;hpb=6500cebaa2c93512d544719956af259ca13f83b7

diff --git a/yaffs_checkptrw.c b/yaffs_checkptrw.c
index 7faf286..d897044 100644
--- a/yaffs_checkptrw.c
+++ b/yaffs_checkptrw.c
@@ -1,7 +1,7 @@
 /*
  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * Copyright (C) 2002-2010 Aleph One Ltd.
+ * Copyright (C) 2002-2011 Aleph One Ltd.
  *   for Toby Churchill Ltd and Brightstar Engineering
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
@@ -14,6 +14,41 @@
 #include "yaffs_checkptrw.h"
 #include "yaffs_getblockinfo.h"
 
+struct yaffs_checkpt_chunk_hdr {
+	int version;
+	int seq;
+	u32 sum;
+	u32 xor;
+} ;
+
+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;
@@ -108,25 +143,32 @@ static void yaffs2_checkpt_find_block(struct yaffs_dev *dev)
 		     i++) {
 			int chunk = i * dev->param.chunks_per_block;
 			int realigned_chunk = chunk - dev->chunk_offset;
+			enum yaffs_block_state state;
+			u32 seq;
 
 			dev->param.read_chunk_tags_fn(dev, realigned_chunk,
 						      NULL, &tags);
 			yaffs_trace(YAFFS_TRACE_CHECKPOINT,
-				"find next checkpt block: search: block %d oid %d seq %d eccr %d",
-				i, tags.obj_id, tags.seq_number,
+				"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) {
-				/* 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;
-			}
+			if (tags.seq_number != YAFFS_SEQUENCE_CHECKPOINT_DATA)
+				continue;
+
+			dev->param.query_block_fn(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");
@@ -164,13 +206,13 @@ int yaffs2_checkpt_open(struct yaffs_dev *dev, int writing)
 	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;
+		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
@@ -194,7 +236,7 @@ int yaffs2_get_checkpt_sum(struct yaffs_dev *dev, u32 * sum)
 {
 	u32 composite_sum;
 
-	composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xFF);
+	composite_sum = (dev->checkpt_sum << 8) | (dev->checkpt_xor & 0xff);
 	*sum = composite_sum;
 	return 1;
 }
@@ -242,7 +284,6 @@ static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
 
 	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) {
@@ -251,6 +292,9 @@ static int yaffs2_checkpt_flush_buffer(struct yaffs_dev *dev)
 	}
 	memset(dev->checkpt_buffer, 0, dev->data_bytes_per_chunk);
 
+	yaffs2_checkpt_init_chunk_hdr(dev);
+
+
 	return 1;
 }
 
@@ -333,14 +377,18 @@ int yaffs2_checkpt_rd(struct yaffs_dev *dev, void *data, int n_bytes)
 				ok = 0;
 				break;
 			}
+			if(!yaffs2_checkpt_check_chunk_hdr(dev)) {
+				ok = 0;
+				break;
+			}
 
-			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;
+
 		}
 
 		*data_bytes = dev->checkpt_buffer[dev->checkpt_byte_offs];
@@ -360,7 +408,8 @@ int yaffs_checkpt_close(struct yaffs_dev *dev)
 	int i;
 
 	if (dev->checkpt_open_write) {
-		if (dev->checkpt_byte_offs != 0)
+		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;