From e59d0af19936b23c788fc717f7f4fda7c4d4a537 Mon Sep 17 00:00:00 2001
From: Zach Brown <zab@versity.com>
Date: Thu, 17 Mar 2016 16:28:44 -0700
Subject: [PATCH] Print full map and ring blocks

In the first pass we'd only printed the first map and ring blocks.

This reads the number of used map blocks into an allocation large enough
for the maximum number of map blocks.

Then we use the block numbers from the map blocks to print the active
ring blocks which are described by the super.

Signed-off-by: Zach Brown <zab@versity.com>
---
 utils/src/print.c | 95 ++++++++++++++++++++++++++++++++++-------------
 1 file changed, 70 insertions(+), 25 deletions(-)

diff --git a/utils/src/print.c b/utils/src/print.c
index f00ef3e3..fe64f18a 100644
--- a/utils/src/print.c
+++ b/utils/src/print.c
@@ -256,33 +256,68 @@ static int print_ring_block(int fd, u64 blkno, __le64 *log_segs)
 	return ret;
 }
 
-static int print_map_block(int fd, u64 blkno, __le64 *log_segs)
+/*
+ * Print all the active ring blocks that are referenced by the super
+ * and which were mapped by the map blocks that we printed.
+ */
+static int print_ring_blocks(int fd, struct scoutfs_super_block *super,
+			     u64 *ring_blknos, __le64 *log_segs)
 {
-	struct scoutfs_ring_map_block *map;
+	u64 block;
+	u64 blkno;
+	u64 i;
 	int ret = 0;
 	int err;
-	int i;
 
-	map = read_block(fd, blkno);
-	if (!map)
-		return -ENOMEM;
+	block = le64_to_cpu(super->ring_first_block);
 
-	printf("map block:\n");
-	print_block_header(&map->hdr);
-	printf("    nr_chunks: %u\n", le32_to_cpu(map->nr_chunks));
+	for (i = 0; i < le64_to_cpu(super->ring_active_blocks); i++) {
+		blkno = ring_blknos[block >> SCOUTFS_CHUNK_BLOCK_SHIFT] +
+			(block & SCOUTFS_CHUNK_BLOCK_MASK);
 
-	printf("    blknos: ");
-	for (i = 0; i < le32_to_cpu(map->nr_chunks); i++)
-		printf("    %llu\n", le64_to_cpu(map->blknos[i]));
-
-	for (i = 0; i < le32_to_cpu(map->nr_chunks); i++) {
-		err = print_ring_block(fd, le64_to_cpu(map->blknos[i]),
-				       log_segs);
+		err = print_ring_block(fd, blkno, log_segs);
 		if (err && !ret)
 			ret = err;
+
+		if (++block == le64_to_cpu(super->ring_total_blocks))
+			block = 0;
+	}
+
+	return ret;
+}
+
+/*
+ * print a chunk's worth of map blocks and stop if we hit a partial
+ * block.
+ */
+static int print_map_blocks(int fd, u64 blkno, u64 *ring_blknos)
+{
+	struct scoutfs_ring_map_block *map;
+	int r = 0;
+	int b;
+	int i;
+
+	for (b = 0; SCOUTFS_BLOCKS_PER_CHUNK; b++) {
+		map = read_block(fd, blkno + b);
+		if (!map)
+			return -ENOMEM;
+
+		printf("map block:\n");
+		print_block_header(&map->hdr);
+		printf("    nr_chunks: %u\n", le32_to_cpu(map->nr_chunks));
+
+		printf("    blknos: ");
+		for (i = 0; i < le32_to_cpu(map->nr_chunks); i++, r++) {
+			printf("    %llu\n", le64_to_cpu(map->blknos[i]));
+			ring_blknos[r] = le64_to_cpu(map->blknos[i]);
+		}
+
+		free(map);
+
+		if (i != SCOUTFS_RING_MAP_BLOCKS)
+			break;
 	}
 
-	free(map);
 	return 0;
 }
 
@@ -291,8 +326,8 @@ static int print_super_brick(int fd)
 	struct scoutfs_super_block *super;
 	char uuid_str[37];
 	__le64 *log_segs;
+	u64 *ring_blknos;
 	u64 total_chunks;
-	size_t bytes;
 	int ret = 0;
 	int err;
 
@@ -326,16 +361,23 @@ static int print_super_brick(int fd)
 	       le64_to_cpu(super->ring_total_blocks),
 	       le64_to_cpu(super->ring_seq));
 
-	/* XXX by hand? */
-	bytes = (total_chunks + 63) / 8;
-	log_segs = malloc(bytes);
-	if (!log_segs) {
+	/*
+	 * Allocate a bitmap big enough to describe all the chunks and
+	 * we can have at most a full chunk worth of map blocks.
+	 */
+	log_segs = calloc(1, (total_chunks + 63) / 8);
+	ring_blknos = calloc(1, SCOUTFS_CHUNK_SIZE);
+	if (!log_segs || !ring_blknos) {
 		ret = -ENOMEM;
 		goto out;
 	}
-	memset(log_segs, 0, bytes);
 
-	err = print_map_block(fd, le64_to_cpu(super->ring_map_blkno), log_segs);
+	err = print_map_blocks(fd, le64_to_cpu(super->ring_map_blkno),
+			       ring_blknos);
+	if (err && !ret)
+		ret = err;
+
+	err = print_ring_blocks(fd, super, ring_blknos, log_segs);
 	if (err && !ret)
 		ret = err;
 
@@ -344,8 +386,11 @@ static int print_super_brick(int fd)
 		ret = err;
 
 out:
+	if (log_segs)
+		free(log_segs);
+	if (ring_blknos)
+		free(ring_blknos);
 	free(super);
-	free(log_segs);
 	return ret;
 }