X-Git-Url: http://www.aleph1.co.uk/gitweb/?p=yaffs2.git;a=blobdiff_plain;f=yaffs_summary.c;h=def00525a0ed7c2cc1e21e625993860da8d3776e;hp=04ef96b09e84712634ffbc28ecd6a08d7acc491a;hb=e49491a81d17bbede16583e9cd2498ede4ed2322;hpb=1570788072c1154eff93282e0bb8564de40bd8aa

diff --git a/yaffs_summary.c b/yaffs_summary.c
index 04ef96b..def0052 100644
--- a/yaffs_summary.c
+++ b/yaffs_summary.c
@@ -11,26 +11,47 @@
  * published by the Free Software Foundation.
  */
 
-/* Summaries write all the tags for the chunks in a block into packed tags
- * (just the tags part - no ECC) in the last n chunks of the block.
+/* Summaries write the useful part of the tags for the chunks in a block into an
+ * an array which is written to the last n chunks of the block.
  * Reading the summaries gives all the tags for the block in one read. Much
  * faster.
  *
  * Chunks holding summaries are marked with tags making it look like
  * they are part of a fake file.
+ *
+ * The summary could also be used during gc.
+ *
  */
 
 #include "yaffs_summary.h"
 #include "yaffs_packedtags2.h"
 #include "yaffs_nand.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_bitmap.h"
 
-/* Summary tags don't need the sequence number becase that is redundant. */
+/*
+ * The summary is built up in an array of summary tags.
+ * This gets written to the last one or two (maybe more) chunks in a block.
+ * A summary header is written as the first part of each chunk of summary data.
+ * The summary header must match or the summary is rejected.
+ */
+ 
+/* Summary tags don't need the sequence number because that is redundant. */
 struct yaffs_summary_tags {
 	unsigned obj_id;
 	unsigned chunk_id;
 	unsigned n_bytes;
 };
 
+/* Summary header */
+struct yaffs_summary_header {
+	unsigned version;	/* Must match current version */
+	unsigned block;		/* Must be this block */
+	unsigned seq;		/* Must be this sequence number */
+	unsigned sum;		/* Just add up all the bytes in the tags */
+};
+
+
 static void yaffs_summary_clear(struct yaffs_dev *dev)
 {
 	if(!dev->sum_tags)
@@ -39,92 +60,151 @@ static void yaffs_summary_clear(struct yaffs_dev *dev)
 		sizeof(struct yaffs_summary_tags));
 }
 
+
+void yaffs_summary_deinit(struct yaffs_dev *dev)
+{
+	kfree(dev->sum_tags);
+	dev->sum_tags = NULL;
+	kfree(dev->gc_sum_tags);
+	dev->gc_sum_tags = NULL;
+	dev->chunks_per_summary = 0;
+}
+
 int yaffs_summary_init(struct yaffs_dev *dev)
 {
-	struct yaffs_summary_tags *sum;
 	int sum_bytes;
 	int chunks_used; /* Number of chunks used by summary */
+	int sum_tags_bytes;
 
 	sum_bytes = dev->param.chunks_per_block *
 			sizeof(struct yaffs_summary_tags);
 
 	chunks_used = (sum_bytes + dev->data_bytes_per_chunk - 1)/
-			dev->data_bytes_per_chunk;
+			(dev->data_bytes_per_chunk - 
+				sizeof(struct yaffs_summary_header));
+
 	dev->chunks_per_summary = dev->param.chunks_per_block - chunks_used;
-	sum = kmalloc(sizeof(struct yaffs_summary_tags) *
-				dev->chunks_per_summary, GFP_NOFS);
-	if(!sum)
+	sum_tags_bytes = sizeof(struct yaffs_summary_tags) *
+				dev->chunks_per_summary;
+	dev->sum_tags = kmalloc(sum_tags_bytes, GFP_NOFS);
+	dev->gc_sum_tags = kmalloc(sum_tags_bytes, GFP_NOFS);
+	if(!dev->sum_tags || !dev->gc_sum_tags) {
+		yaffs_summary_deinit(dev);
 		return YAFFS_FAIL;
+	}
 
-	dev->sum_tags = sum;
 	yaffs_summary_clear(dev);
 
 	return YAFFS_OK;
 }
 
-void yaffs_summary_deinit(struct yaffs_dev *dev)
+static unsigned yaffs_summary_sum(struct yaffs_dev *dev)
 {
-	if(dev->sum_tags) {
-		kfree(dev->sum_tags);
-		dev->sum_tags = NULL;
+	u8 *sum_buffer = (u8 *)dev->sum_tags;
+	int i;
+	unsigned sum = 0;
+
+	i = sizeof(struct yaffs_summary_tags) *
+				dev->chunks_per_summary;;
+	while(i > 0){
+		sum += *sum_buffer;
+		sum_buffer++;
+		i--;
 	}
-	dev->chunks_per_summary = 0;
+
+	return sum;	
 }
 
-static int yaffs_summary_write(struct yaffs_dev *dev)
+static int yaffs_summary_write(struct yaffs_dev *dev, int blk)
 {
 	struct yaffs_ext_tags tags;
 	u8 *buffer;
 	u8 *sum_buffer = (u8 *)dev->sum_tags;
 	int n_bytes;
 	int chunk_in_nand;
+	int chunk_in_block;
 	int result;
 	int this_tx;
+	struct yaffs_summary_header hdr;
+	int sum_bytes_per_chunk = dev->data_bytes_per_chunk - sizeof(hdr);
+	struct yaffs_block_info *bi = yaffs_get_block_info(dev, blk);
 
 	buffer = yaffs_get_temp_buffer(dev);
-	n_bytes = sizeof(struct yaffs_summary_tags) * dev->chunks_per_summary;
+	n_bytes = sizeof(struct yaffs_summary_tags) *
+				dev->chunks_per_summary;
 	memset(&tags, 0, sizeof(struct yaffs_ext_tags));
 	tags.obj_id = YAFFS_OBJECTID_SUMMARY;
 	tags.chunk_id = 1;
+	chunk_in_block = dev->chunks_per_summary;
 	chunk_in_nand = dev->alloc_block * dev->param.chunks_per_block +
 						dev-> chunks_per_summary;
+	hdr.version = YAFFS_SUMMARY_VERSION;
+	hdr.block = blk;
+	hdr.seq = bi->seq_number;
+	hdr.sum = yaffs_summary_sum(dev);
+	
 	do {
 		this_tx = n_bytes;
-		if (this_tx > dev->data_bytes_per_chunk)
-			this_tx = dev->data_bytes_per_chunk;
-		memcpy(buffer, sum_buffer, this_tx);
-		tags.n_bytes = this_tx;
+		if (this_tx > sum_bytes_per_chunk)
+			this_tx = sum_bytes_per_chunk;
+		memcpy(buffer, &hdr, sizeof(hdr));
+		memcpy(buffer + sizeof(hdr), sum_buffer, this_tx);
+		tags.n_bytes = this_tx + sizeof(hdr);
 		result = yaffs_wr_chunk_tags_nand(dev, chunk_in_nand,
 						buffer, &tags);
+
+		if (result != YAFFS_OK)
+			break;
+		yaffs_set_chunk_bit(dev, blk, chunk_in_block);
+		bi->pages_in_use++;
+		dev->n_free_chunks--;
+
 		n_bytes -= this_tx;
 		sum_buffer += this_tx;
 		chunk_in_nand++;
+		chunk_in_block++;
 		tags.chunk_id++;
 	} while (result == YAFFS_OK && n_bytes > 0);
 	yaffs_release_temp_buffer(dev, buffer);
+
+
+	if (result == YAFFS_OK)
+		bi->has_summary = 1;
+
+
 	return result;
 }
 
-int yaffs_summary_read(struct yaffs_dev *dev, int blk)
+int yaffs_summary_read(struct yaffs_dev *dev,
+			struct yaffs_summary_tags *st,
+			int blk)
 {
 	struct yaffs_ext_tags tags;
 	u8 *buffer;
-	u8 *sum_buffer = (u8 *)dev->sum_tags;
+	u8 *sum_buffer = (u8 *)st;
 	int n_bytes;
 	int chunk_id;
 	int chunk_in_nand;
+	int chunk_in_block;
 	int result;
 	int this_tx;
+	struct yaffs_summary_header hdr;
+	struct yaffs_block_info *bi = yaffs_get_block_info(dev, blk);
+	int sum_bytes_per_chunk = dev->data_bytes_per_chunk - sizeof(hdr);
+	int sum_tags_bytes;
 
+	sum_tags_bytes = sizeof(struct yaffs_summary_tags) *
+				dev->chunks_per_summary;
 	buffer = yaffs_get_temp_buffer(dev);
 	n_bytes = sizeof(struct yaffs_summary_tags) * dev->chunks_per_summary;
+	chunk_in_block = dev->chunks_per_summary;
 	chunk_in_nand = blk * dev->param.chunks_per_block +
 							dev->chunks_per_summary;
 	chunk_id = 1;
 	do {
 		this_tx = n_bytes;
-		if(this_tx > dev->data_bytes_per_chunk)
-			this_tx = dev->data_bytes_per_chunk;
+		if(this_tx > sum_bytes_per_chunk)
+			this_tx = sum_bytes_per_chunk;
 		result = yaffs_rd_chunk_tags_nand(dev, chunk_in_nand,
 						buffer, &tags);
 
@@ -132,51 +212,67 @@ int yaffs_summary_read(struct yaffs_dev *dev, int blk)
 			tags.obj_id != YAFFS_OBJECTID_SUMMARY ||
 			tags.chunk_used == 0 ||
 			tags.ecc_result > YAFFS_ECC_RESULT_FIXED ||
-			this_tx != tags.n_bytes)
+			tags.n_bytes != (this_tx + sizeof(hdr)))
 				result = YAFFS_FAIL;
 		if (result != YAFFS_OK)
 			break;
 
-		memcpy(sum_buffer, buffer, this_tx);
+		if (st == dev->sum_tags) {
+			/* If we're scanning then update the block info */
+			yaffs_set_chunk_bit(dev, blk, chunk_in_block);
+			bi->pages_in_use++;
+		}
+		memcpy(&hdr, buffer, sizeof(hdr));
+		memcpy(sum_buffer, buffer + sizeof(hdr), this_tx);
 		n_bytes -= this_tx;
 		sum_buffer += this_tx;
 		chunk_in_nand++;
+		chunk_in_block++;
 		chunk_id++;
-		dev->n_free_chunks--;
 	} while (result == YAFFS_OK && n_bytes > 0);
 	yaffs_release_temp_buffer(dev, buffer);
+
+	if(result == YAFFS_OK) {
+		/* Verify header */		
+		if (hdr.version != YAFFS_SUMMARY_VERSION ||
+		    hdr.block != blk ||
+		    hdr.seq != bi->seq_number ||
+		    hdr.sum != yaffs_summary_sum(dev))
+		    result = YAFFS_FAIL;
+	}
+	
+	if (st == dev->sum_tags && result == YAFFS_OK)
+		bi->has_summary = 1;
+
 	return result;
 }
+
 int yaffs_summary_add(struct yaffs_dev *dev,
 			struct yaffs_ext_tags *tags,
 			int chunk_in_nand)
 {
 	struct yaffs_packed_tags2_tags_only tags_only;
 	struct yaffs_summary_tags *sum_tags;
+	int block_in_nand = chunk_in_nand / dev->param.chunks_per_block;
 	int chunk_in_block = chunk_in_nand % dev->param.chunks_per_block;
 
 	if(!dev->sum_tags)
 		return YAFFS_OK;
 
-	printf("Add summary for chunk %d tags (%d %d %d)",chunk_in_block,
-			tags->seq_number, tags->obj_id, tags->chunk_id);
 	if(chunk_in_block >= 0 && chunk_in_block < dev->chunks_per_summary) {
 		yaffs_pack_tags2_tags_only(&tags_only, tags);
 		sum_tags = &dev->sum_tags[chunk_in_block];
 		sum_tags->chunk_id = tags_only.chunk_id;
 		sum_tags->n_bytes = tags_only.n_bytes;
 		sum_tags->obj_id = tags_only.obj_id;
-		printf(" added %d %d %d", sum_tags->obj_id, sum_tags->chunk_id, sum_tags->n_bytes);
 
 		if(chunk_in_block == dev->chunks_per_summary - 1) {
-			printf(" Write summary");
 			/* Time to write out the summary */
-			yaffs_summary_write(dev);
+			yaffs_summary_write(dev, block_in_nand);
 			yaffs_summary_clear(dev);
 			yaffs_skip_rest_of_block(dev);
 		}
 	}
-	printf("\n");
 	return YAFFS_OK;
 }
 
@@ -196,3 +292,21 @@ int yaffs_summary_fetch(struct yaffs_dev *dev,
 	}
 	return YAFFS_FAIL;
 }
+
+void yaffs_summary_gc(struct yaffs_dev *dev, int blk)
+{
+	struct yaffs_block_info *bi = yaffs_get_block_info(dev, blk);
+	int i;
+
+	if (!bi->has_summary)
+		return;
+
+	for (i = dev->chunks_per_summary; i < dev->param.chunks_per_block; i++) {
+		if( yaffs_check_chunk_bit(dev, blk, i)) {
+			yaffs_clear_chunk_bit(dev, blk, i);
+			bi->pages_in_use--;
+			dev->n_free_chunks++;
+		}
+	}
+
+}