[PATCH] Add btrfs-show-super

[Goffredo Baroncelli <kreijack@gmail.com>]

Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
---
 Makefile           |    5 +-
 btrfs-show-super.c |  284 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 288 insertions(+), 1 deletion(-)
 create mode 100644 btrfs-show-super.c

diff --git a/Makefile b/Makefile
index 4894903..0630b5d 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,7 @@ RESTORE_LIBS=-lz
 
 progs = btrfsctl mkfs.btrfs btrfs-debug-tree btrfs-show btrfs-vol btrfsck \
 	btrfs btrfs-map-logical btrfs-image btrfs-zero-log btrfs-convert \
-	btrfs-find-root btrfs-restore btrfstune
+	btrfs-find-root btrfs-restore btrfstune btrfs-show-super
 
 # make C=1 to enable sparse
 ifdef C
@@ -75,6 +75,9 @@ btrfs-debug-tree: $(objects) debug-tree.o
 btrfs-zero-log: $(objects) btrfs-zero-log.o
 	$(CC) $(CFLAGS) -o btrfs-zero-log $(objects) btrfs-zero-log.o $(LDFLAGS) $(LIBS)
 
+btrfs-show-super: $(objects) btrfs-show-super.o
+	$(CC) $(CFLAGS) -o btrfs-show-super $(objects) btrfs-show-super.o $(LDFLAGS) $(LIBS)
+
 btrfs-select-super: $(objects) btrfs-select-super.o
 	$(CC) $(CFLAGS) -o btrfs-select-super $(objects) btrfs-select-super.o $(LDFLAGS) $(LIBS)
 
diff --git a/btrfs-show-super.c b/btrfs-show-super.c
new file mode 100644
index 0000000..a9e2524
--- /dev/null
+++ b/btrfs-show-super.c
@@ -0,0 +1,284 @@
+/*
+ * Copyright (C) 2012 STRATO AG.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#define _XOPEN_SOURCE 500
+#define _GNU_SOURCE 1
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <ctype.h>
+#include <uuid/uuid.h>
+#include <errno.h>
+
+#include "kerncompat.h"
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "transaction.h"
+#include "list.h"
+#include "version.h"
+#include "utils.h"
+#include "crc32c.h"
+
+static void print_usage(void);
+static void dump_superblock(struct btrfs_super_block *sb);
+int main(int argc, char **argv);
+static int load_and_dump_sb(char *, int fd, u64 sb_bytenr);
+
+
+static void print_usage(void)
+{
+	fprintf(stderr,
+		"usage: btrfs-show-super [-i super_mirror|-a] dev [dev..]\n");
+	fprintf(stderr, "\tThe super_mirror number is between 0 and %d.\n",
+		BTRFS_SUPER_MIRROR_MAX - 1);
+	fprintf(stderr, "\tIf -a is passed all the superblocks are showed.\n",
+		BTRFS_SUPER_MIRROR_MAX - 1);
+	fprintf(stderr, "%s\n", BTRFS_BUILD_VERSION);
+}
+
+int main(int argc, char **argv)
+{
+	int opt;
+	int all = 0;
+	char *filename;
+	int fd = -1;
+	int arg, i;
+	u64 sb_bytenr = btrfs_sb_offset(0);
+
+	while ((opt = getopt(argc, argv, "ai:")) != -1) {
+		switch (opt) {
+		case 'i':
+			arg = atoi(optarg);
+
+			if (arg < 0 || arg >= BTRFS_SUPER_MIRROR_MAX) {
+				fprintf(stderr,
+					"Illegal super_mirror %d\n",
+					arg);
+				print_usage();
+				exit(1);
+			}
+			sb_bytenr = btrfs_sb_offset(arg);
+			break;
+
+		case 'a':
+			all = 1;
+			break;
+
+		default:
+			print_usage();
+			exit(1);
+		}
+	}
+
+	if (argc < optind + 1) {
+		print_usage();
+		exit(1);
+	}
+
+	for (i = optind ; i < argc ; i++) {
+		filename = argv[i];
+		fd = open(filename, O_RDONLY, 0666);
+		if (fd < 0) {
+			fprintf(stderr, "Could not open %s\n", filename);
+			close(fd);
+			exit(1);
+		}
+
+		if (all) {
+			int idx;
+			for (idx = 0 ; idx < BTRFS_SUPER_MIRROR_MAX ; idx++) {
+				sb_bytenr = btrfs_sb_offset(idx);
+				if (load_and_dump_sb(filename, fd, sb_bytenr)) {
+					close(fd);
+					exit(1);
+				}
+
+				putchar('\n');
+			}
+		} else {
+			load_and_dump_sb(filename, fd, sb_bytenr);
+			putchar('\n');
+		}
+		close(fd);
+	}
+
+	exit(0);
+}
+
+static int load_and_dump_sb(char *filename, int fd, u64 sb_bytenr)
+{
+	u8	super_block_data[BTRFS_SUPER_INFO_SIZE];
+	struct btrfs_super_block *sb;
+	u64 ret;
+
+	sb = (struct btrfs_super_block *)super_block_data;
+
+	ret = pread64(fd, super_block_data, BTRFS_SUPER_INFO_SIZE, sb_bytenr);
+	if (ret != BTRFS_SUPER_INFO_SIZE) {
+		int e = errno;
+
+		/* check if the disk if too short for further superblock */
+		if (ret == 0 && e == 0)
+			return 0;
+
+		fprintf(stderr,
+		   "ERROR: Failed to read the superblock on %s at %llu\n",
+		   filename, (unsigned long long)sb_bytenr);
+		fprintf(stderr,
+		   "ERROR: error = '%s', errno = %d\n", strerror(e), e);
+		return 1;
+	}
+	printf("superblock: bytenr=%llu, device=%s\n", sb_bytenr, filename);
+	printf("---------------------------------------------------------\n");
+	dump_superblock(sb);
+	return 0;
+}
+
+static int check_csum_sblock(void *sb, int csum_size)
+{
+	char result[csum_size];
+	u32 crc = ~(u32)0;
+
+	crc = btrfs_csum_data(NULL, (char *)sb + BTRFS_CSUM_SIZE,
+				crc, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+	btrfs_csum_final(crc, result);
+
+	return !memcmp(sb, &result, csum_size);
+}
+
+static void dump_superblock(struct btrfs_super_block *sb)
+{
+	int	i;
+	char	*s, buf[36+1];
+	u8	*p;
+
+	printf("csum\t\t\t0x");
+	for (i = 0, p = sb->csum ; i < btrfs_super_csum_size(sb) ; i++)
+		printf("%02x", p[i]);
+	if (check_csum_sblock(sb, btrfs_super_csum_size(sb)))
+		printf(" [match]");
+	else
+		printf(" [DON'T MATCH]");
+	putchar('\n');
+
+	printf("bytenr\t\t\t%llu\n",
+		(unsigned long long)btrfs_super_bytenr(sb));
+	printf("flags\t\t\t0x%llx\n",
+		(unsigned long long)btrfs_super_flags(sb));
+
+	printf("magic\t\t\t");
+	s = (char *) &sb->magic;
+	for (i = 0 ; i < 8 ; i++)
+		putchar(isprint(s[i]) ? s[i] : '.');
+	if (!memcmp(BTRFS_MAGIC, &sb->magic, 8))
+		printf(" [match]\n");
+	else
+		printf(" [DON'T MATCH]\n");
+
+	uuid_unparse(sb->fsid, buf);
+	printf("fsid\t\t\t%s\n", buf);
+
+	printf("label\t\t\t");
+	s = sb->label;
+	for (i = 0 ; i < BTRFS_LABEL_SIZE && s[i] ; i++)
+		putchar(isprint(s[i]) ? s[i] : '.');
+	putchar('\n');
+
+	printf("generation\t\t%llu\n",
+	       (unsigned long long)btrfs_super_generation(sb));
+	printf("root\t\t\t%llu\n", (unsigned long long)btrfs_super_root(sb));
+	printf("sys_array_size\t\t%llu\n",
+	       (unsigned long long)btrfs_super_sys_array_size(sb));
+	printf("chunk_root_generation\t%llu\n",
+	       (unsigned long long)btrfs_super_chunk_root_generation(sb));
+	printf("root_level\t\t%llu\n",
+	       (unsigned long long)btrfs_super_root_level(sb));
+	printf("chunk_root\t\t%llu\n",
+	       (unsigned long long)btrfs_super_chunk_root(sb));
+	printf("chunk_root_level\t%llu\n",
+	       (unsigned long long)btrfs_super_chunk_root_level(sb));
+	printf("log_root\t\t%llu\n",
+	       (unsigned long long)btrfs_super_log_root(sb));
+	printf("log_root_transid\t%llu\n",
+	       (unsigned long long)btrfs_super_log_root_transid(sb));
+	printf("log_root_level\t\t%llu\n",
+	       (unsigned long long)btrfs_super_log_root_level(sb));
+	printf("total_bytes\t\t%llu\n",
+	       (unsigned long long)btrfs_super_total_bytes(sb));
+	printf("bytes_used\t\t%llu\n",
+	       (unsigned long long)btrfs_super_bytes_used(sb));
+	printf("sectorsize\t\t%llu\n",
+	       (unsigned long long)btrfs_super_sectorsize(sb));
+	printf("nodesize\t\t%llu\n",
+	       (unsigned long long)btrfs_super_nodesize(sb));
+	printf("leafsize\t\t%llu\n",
+	       (unsigned long long)btrfs_super_leafsize(sb));
+	printf("stripesize\t\t%llu\n",
+	       (unsigned long long)btrfs_super_stripesize(sb));
+	printf("root_dir\t\t%llu\n",
+	       (unsigned long long)btrfs_super_root_dir(sb));
+	printf("num_devices\t\t%llu\n",
+	       (unsigned long long)btrfs_super_num_devices(sb));
+	printf("compat_flags\t\t0x%llx\n",
+	       (unsigned long long)btrfs_super_compat_flags(sb));
+	printf("compat_ro_flags\t\t0x%llx\n",
+	       (unsigned long long)btrfs_super_compat_ro_flags(sb));
+	printf("incompat_flags\t\t0x%llx\n",
+	       (unsigned long long)btrfs_super_incompat_flags(sb));
+	printf("csum_type\t\t%llu\n",
+	       (unsigned long long)btrfs_super_csum_type(sb));
+	printf("csum_size\t\t%llu\n",
+	       (unsigned long long)btrfs_super_csum_size(sb));
+	printf("cache_generation\t%llu\n",
+	       (unsigned long long)btrfs_super_cache_generation(sb));
+
+	uuid_unparse(sb->dev_item.uuid, buf);
+	printf("dev_item.uuid\t\t%s\n", buf);
+
+	uuid_unparse(sb->dev_item.fsid, buf);
+	printf("dev_item.fsid\t\t%s %s\n", buf,
+		!memcmp(sb->dev_item.fsid, sb->fsid, BTRFS_FSID_SIZE) ?
+			"[match]" : "[DON'T MATCH]");
+
+	printf("dev_item.type\t\t%llu\n", (unsigned long long)
+	       btrfs_stack_device_type(&sb->dev_item));
+	printf("dev_item.total_bytes\t%llu\n", (unsigned long long)
+	       btrfs_stack_device_total_bytes(&sb->dev_item));
+	printf("dev_item.bytes_used\t%llu\n", (unsigned long long)
+	       btrfs_stack_device_bytes_used(&sb->dev_item));
+	printf("dev_item.io_align\t%u\n", (unsigned int)
+	       btrfs_stack_device_io_align(&sb->dev_item));
+	printf("dev_item.io_width\t%u\n", (unsigned int)
+	       btrfs_stack_device_io_width(&sb->dev_item));
+	printf("dev_item.sector_size\t%u\n", (unsigned int)
+	       btrfs_stack_device_sector_size(&sb->dev_item));
+	printf("dev_item.devid\t\t%llu\n",
+	       btrfs_stack_device_id(&sb->dev_item));
+	printf("dev_item.dev_group\t%u\n", (unsigned int)
+	       btrfs_stack_device_group(&sb->dev_item));
+	printf("dev_item.seek_speed\t%u\n", (unsigned int)
+	       btrfs_stack_device_seek_speed(&sb->dev_item));
+	printf("dev_item.bandwidth\t%u\n", (unsigned int)
+	       btrfs_stack_device_bandwidth(&sb->dev_item));
+	printf("dev_item.generation\t%llu\n", (unsigned long long)
+	       btrfs_stack_device_generation(&sb->dev_item));
+}
+
-- 
1.7.10.4