diff mbox

Add btrfs-show-super

Message ID 1351865850-21688-2-git-send-email-kreijack@inwind.it (mailing list archive)
State New, archived
Headers show

Commit Message

Goffredo Baroncelli Nov. 2, 2012, 2:17 p.m. UTC 
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

Comments

Stefan Behrens Nov. 2, 2012, 8:44 p.m. UTC | #1 
On 11/02/2012 15:17, Goffredo Baroncelli wrote:
> 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
>

Good enhancement! Thank you! I like and recommend this enhanced version 
of the btrfs-show-super tool.

Goffredo, you are doing a very good and valuable job on improving the 
Btrfs tools. And you are one of the main contributors to btrfs-progs. 
Especially because of the huge amount of code that you are contributing, 
I would like to ask you to make your C source code formatting rules 
consistent with the rest of the Btrfs source code. In particular, I am 
talking about the way you use spaces. It is always the first thing that 
I notice, and quite often I just stop reading patches after noticing 
that the C source formatting is violating the rules. Just imagine that 
the Linux kernel would be written in hundreds of different C formatting 
styles. What a pain for the eyes this would be. Patches would contain 
99% formatting changes. Source code would be almost unreadable. 
Therefore strict rules have been established how to format C code 
(including how to use spaces in the C code). The same rules should be 
applied to the btrfs-progs code. Please, please, please reconsider the 
way you place spaces when you submit Btrfs patches! See below. Don't 
feel offended, just place the spaces correctly, please! Your work is 
good, just the way you place spaces is not good :)


[...]
> +	for ( i = optind ; i < argc ; i++ ) {
+	for (i = optind; i < argc ; i++) {

[...]
> +		if (all){
> +			int idx;
> +			for (idx = 0 ; idx < BTRFS_SUPER_MIRROR_MAX ; idx++) {
+		if (all) {
+			int idx;
+			for (idx = 0; idx < BTRFS_SUPER_MIRROR_MAX; idx++) {

[...]
> +	if (ret != BTRFS_SUPER_INFO_SIZE ) {
> +		int e = errno;
> +
> +		/* check if the disk if too short for further superblock */
> +		if( ret == 0 && e == 0 )
+	if (ret != BTRFS_SUPER_INFO_SIZE) {
+		int e = errno;
+
+		/* check if the disk if too short for further superblock */
+		if (ret == 0 && e == 0)

[...]
> +	for (i = 0, p = sb->csum ; i < btrfs_super_csum_size(sb) ; i++ )
+	for (i = 0, p = sb->csum; i < btrfs_super_csum_size(sb); i++)

[...]
> +	for (i = 0 ; i < 8 ; i++ )
+	for (i = 0; i < 8; i++)

[...]
> +	for (i = 0 ; i < BTRFS_LABEL_SIZE && s[i] ; i++)
+	for (i = 0; i < BTRFS_LABEL_SIZE && s[i]; i++)


The Linux kernel sources contain docs and tools for the formatting issue:
- Documentation/CodingStyle describes the C source code formatting rules 
that are expected in the Linux world.
- scripts/checkpatch.pl can detect lots of violations to these 
formatting rules.

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diff mbox

Patch

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..89d265c
--- /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));
+}
+