Example usage:
btrfs inspect-internal dump-csum /btrfs/50gbfile /dev/sda4
csum for /btrfs/50gbfile dumped to /btrfs/50gbfile.csumdump
Signed-off-by: Lakshmipathi.G <lakshmipath...@giis.co.in>
---
Makefile | 3 +-
cmds-inspect-dump-csum.c | 256 +++++++++++++++++++++++++++++++++++++++++++++++
cmds-inspect-dump-csum.h | 24 +++++
cmds-inspect.c | 3 +
4 files changed, 285 insertions(+), 1 deletion(-)
create mode 100644 cmds-inspect-dump-csum.c
create mode 100644 cmds-inspect-dump-csum.h
diff --git a/Makefile b/Makefile
index 81598df..6e63e18 100644
--- a/Makefile
+++ b/Makefile
@@ -102,7 +102,7 @@ cmds_objects = cmds-subvolume.o cmds-filesystem.o
cmds-device.o cmds-scrub.o \
cmds-restore.o cmds-rescue.o chunk-recover.o super-recover.o \
cmds-property.o cmds-fi-usage.o cmds-inspect-dump-tree.o \
cmds-inspect-dump-super.o cmds-inspect-tree-stats.o cmds-fi-du.o
\
- mkfs/common.o
+ cmds-inspect-dump-csum.o mkfs/common.o
libbtrfs_objects = send-stream.o send-utils.o kernel-lib/rbtree.o btrfs-list.o
\
kernel-lib/crc32c.o messages.o \
uuid-tree.o utils-lib.o rbtree-utils.o
@@ -191,6 +191,7 @@ btrfs_convert_cflags =
-DBTRFSCONVERT_EXT2=$(BTRFSCONVERT_EXT2)
btrfs_fragments_libs = -lgd -lpng -ljpeg -lfreetype
btrfs_debug_tree_objects = cmds-inspect-dump-tree.o
btrfs_show_super_objects = cmds-inspect-dump-super.o
+btrfs_dump_csum_objects = cmds-inspect-dump-csum.o
btrfs_calc_size_objects = cmds-inspect-tree-stats.o
# collect values of the variables above
diff --git a/cmds-inspect-dump-csum.c b/cmds-inspect-dump-csum.c
new file mode 100644
index 0000000..6065eb4
--- /dev/null
+++ b/cmds-inspect-dump-csum.c
@@ -0,0 +1,256 @@
+/*
+ * 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.
+ */
+
+#include "kerncompat.h"
+#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 <getopt.h>
+
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "transaction.h"
+#include "list.h"
+#include "utils.h"
+#include "commands.h"
+#include "crc32c.h"
+#include "cmds-inspect-dump-csum.h"
+#include "help.h"
+#include "volumes.h"
+
+
+const char * const cmd_inspect_dump_csum_usage[] = {
+ "btrfs inspect-internal dump-csum <path/to/file> <device>",
+ "Get csums for the given file.",
+ NULL
+};
+
+int btrfs_lookup_csums(struct btrfs_trans_handle *trans, struct btrfs_root
*root,
+ struct btrfs_path *path, u64 bytenr, int cow, int total_csums, FILE *fp)
+{
+ int ret;
+ int i;
+ int start_pos = 0;
+ struct btrfs_key file_key;
+ struct btrfs_key found_key;
+ struct btrfs_csum_item *item;
+ struct extent_buffer *leaf;
+ u64 csum_offset = 0;
+ u16 csum_size =
+ btrfs_super_csum_size(root->fs_info->super_copy);
+ int csums_in_item = 0;
+ unsigned int tree_csum = 0;
+ int pending_csums = total_csums;
+ static int cnt=1;
+
+ file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
+ file_key.offset = bytenr;
+ file_key.type = BTRFS_EXTENT_CSUM_KEY;
+ ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
+ if (ret < 0)
+ goto fail;
+ while(1){
+ leaf = path->nodes[0];
+ if (ret > 0) {
+ ret = 1;
+ if (path->slots[0] == 0)
+ goto fail;
+ path->slots[0]--;
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.type != BTRFS_EXTENT_CSUM_KEY){
+ fprintf(stderr, "\nInvalid key found.");
+ goto fail;
+ }
+
+ csum_offset = ((bytenr - found_key.offset) /
root->sectorsize) * csum_size;
+ csums_in_item = btrfs_item_size_nr(leaf,
path->slots[0]);
+ csums_in_item /= csum_size;
+ csums_in_item -= ( bytenr - found_key.offset ) /
root->sectorsize;
+ start_pos=csum_offset;
+ }
+ if (path->slots[0] >= btrfs_header_nritems(leaf)) {
+ if (pending_csums > 0){
+ ret = btrfs_next_leaf(root, path);
+ if (ret == 0)
+ continue;
+ }
+ }
+ item = btrfs_item_ptr(leaf, path->slots[0], struct
btrfs_csum_item);
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (!ret){
+ start_pos=0;
+ csum_offset = ( bytenr - found_key.offset ) /
root->sectorsize;
+ csums_in_item = btrfs_item_size_nr(leaf,
path->slots[0]);
+ csums_in_item /= csum_size;
+ }
+ if (csums_in_item > pending_csums){
+ //possibly,some other csums on this item.
+ for(i = 0; i < pending_csums; i++, cnt++){
+ read_extent_buffer(leaf, &tree_csum,
+ (unsigned long)item + ((i*4)+start_pos)
, csum_size);
+ fprintf(fp, "%x ", tree_csum);
+ if (cnt % 8 == 0)
+ fprintf(fp, "\n");
+ }
+ pending_csums = 0;
+ return 0;
+ }else{
+ for(i = 0; i < csums_in_item; i++, cnt++){
+ read_extent_buffer(leaf, &tree_csum,
+ (unsigned long)item+((i*4)+start_pos),
csum_size);
+ fprintf(fp, "%x ", tree_csum);
+ if (cnt % 8 == 0)
+ fprintf(fp, "\n");
+ }
+ }
+ pending_csums -= csums_in_item;
+ ret = 0;
+ if (pending_csums > 0){
+ path->slots[0]++;
+
+ }else
+ return 0;
+
+ }
+fail:
+ fprintf(stderr, "btrfs_lookup_csums search failed.");
+ if (ret > 0)
+ ret = -ENOENT;
+ return ret;
+}
+
+int btrfs_lookup_extent(struct btrfs_fs_info *info, struct btrfs_path *path,
+ u64 ino, int cow, FILE *fp){
+ struct btrfs_key key;
+ struct btrfs_key found_key;
+ struct btrfs_file_extent_item *fi;
+ struct extent_buffer *leaf;
+ struct btrfs_root *fs_root;
+ int ret = -1;
+ int slot;
+ int total_csums = 0;
+ u64 bytenr;
+ u64 itemnum = 0;
+ struct btrfs_path *path1 = NULL;
+
+ fs_root = info->fs_root;
+ key.objectid = ino;
+ key.type = BTRFS_EXTENT_DATA_KEY;
+ key.offset = 0;
+ ret = btrfs_search_slot(NULL,fs_root,&key,path,0,0);
+
+ if(ret < 0)
+ goto error;
+
+ if (ret > 1){
+ fprintf(stderr, "Unable to find the entry");
+ return ret;
+ }
+
+ while(1){
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ if (slot >= btrfs_header_nritems(leaf)){
+ ret = btrfs_next_leaf(fs_root, path);
+ if (ret == 0)
+ continue;
+ if (ret < 0)
+ goto error;
+ }
+ btrfs_item_key_to_cpu(leaf, &found_key, slot);
+ if (found_key.type != BTRFS_EXTENT_DATA_KEY){
+ btrfs_release_path(path);
+ return -EINVAL;
+ }
+
+ fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
+ bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
+ total_csums=(btrfs_file_extent_num_bytes(leaf, fi) / 1024) / 4;
+ path->slots[0]++;
+ itemnum++;
+ path1 = btrfs_alloc_path();
+ ret = btrfs_lookup_csums(NULL,info->csum_root, path1, bytenr, 0,
+ total_csums, fp);
+ btrfs_release_path(path1);
+ if (ret) {
+ fprintf(stderr, "\n Error: btrfs_lookup_csum");
+ return 1;
+ }
+ }
+
+error:
+ btrfs_release_path(path);
+ return ret;
+}
+
+int cmd_inspect_dump_csum(int argc, char **argv)
+{
+ struct btrfs_fs_info *info;
+ int ret;
+ struct btrfs_path path;
+ FILE *fp;
+ struct stat st;
+ char *filename;
+ char *outfile;
+
+ if (check_argc_exact(argc, 3))
+ usage(cmd_inspect_dump_csum_usage);
+
+ filename = argv[1];
+ info = open_ctree_fs_info(argv[2], 0, 0, 0, OPEN_CTREE_PARTIAL);
+ if (!info) {
+ fprintf(stderr, "unable to open %s\n", argv[2]);
+ exit(1);
+ }
+
+ ret = stat(filename, &st);
+ if (ret < 0) {
+ fprintf(stderr, "unable to open %s\n", filename);
+ exit(1);
+ }
+
+ if(st.st_size < 1024){
+ fprintf(stderr, "file less than 1KB.abort%lu", (st.st_size ));
+ exit(1);
+ }
+
+ btrfs_init_path(&path);
+ ret = asprintf(&outfile, "%s.csumdump", filename);
+ if (ret == -1){
+ fprintf(stderr, "memory allocation failed.");
+ return -1;
+ }
+ fp = fopen(outfile, "w+");
+ if (NULL == fp) {
+ fprintf(stderr, "Unable to open %s file", outfile);
+ free(outfile);
+ return -1;
+ }
+ ret = btrfs_lookup_extent(info, &path, st.st_ino, 0, fp);
+ fclose(fp);
+ ret = close_ctree(info->fs_root);
+ btrfs_close_all_devices();
+
+ fprintf(stdout, "csum for %s dumped to %s\n ", filename, outfile);
+ free(outfile);
+ return ret;
+}
diff --git a/cmds-inspect-dump-csum.h b/cmds-inspect-dump-csum.h
new file mode 100644
index 0000000..05d1a8f
--- /dev/null
+++ b/cmds-inspect-dump-csum.h
@@ -0,0 +1,24 @@
+/*
+ * 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.
+ *
+ * Authors: Lakshmipathi.G <lakshmipath...@giis.co.in>
+ */
+
+#ifndef __CMDS_INSPECT_DUMP_CSUM_H__
+#define __CMDS_INSPECT_DUMP_CSUM_H__
+
+int cmd_inspect_dump_csum(int argc, char **argv);
+
+extern const char * const cmd_inspect_dump_csum_usage[];
+
+#endif
diff --git a/cmds-inspect.c b/cmds-inspect.c
index 58b5956..3d248d0 100644
--- a/cmds-inspect.c
+++ b/cmds-inspect.c
@@ -34,6 +34,7 @@
#include "cmds-inspect-dump-tree.h"
#include "cmds-inspect-dump-super.h"
#include "cmds-inspect-tree-stats.h"
+#include "cmds-inspect-dump-csum.h"
#include "help.h"
static const char * const inspect_cmd_group_usage[] = {
@@ -650,6 +651,8 @@ const struct cmd_group inspect_cmd_group = {
cmd_inspect_dump_super_usage, NULL, 0 },
{ "tree-stats", cmd_inspect_tree_stats,
cmd_inspect_tree_stats_usage, NULL, 0 },
+ { "dump-csum", cmd_inspect_dump_csum,
+ cmd_inspect_dump_csum_usage, NULL, 0 },
NULL_CMD_STRUCT
}
};
--
2.7.4
--
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