File 0001-Print-csum-for-a-given-file-on-stdout.patch of Package btrfsprogs
From d1aa1e923c96be90690f5ea221f1c46c57c6ff62 Mon Sep 17 00:00:00 2001
From: "lakshmipathi.g" <lakshmipathi.ganapathi@collabora.com>
Date: Tue, 18 May 2021 14:52:41 +0530
Subject: [PATCH] Print csum for a given file on stdout.
Signed-off-by: lakshmipathi.g <lakshmipathi.ganapathi@collabora.com>
---
Makefile | 3 +-
cmds/commands.h | 1 +
cmds/inspect-dump-csum.c | 244 +++++++++++++++++++++++++++++++++++++++
cmds/inspect.c | 1 +
4 files changed, 248 insertions(+), 1 deletion(-)
create mode 100644 cmds/inspect-dump-csum.c
diff --git a/Makefile b/Makefile
index a1cc457b..763dc73f 100644
--- a/Makefile
+++ b/Makefile
@@ -157,7 +157,8 @@ cmds_objects = cmds/subvolume.o cmds/filesystem.o cmds/device.o cmds/scrub.o \
cmds/rescue-super-recover.o \
cmds/property.o cmds/filesystem-usage.o cmds/inspect-dump-tree.o \
cmds/inspect-dump-super.o cmds/inspect-tree-stats.o cmds/filesystem-du.o \
- mkfs/common.o check/mode-common.o check/mode-lowmem.o
+ mkfs/common.o check/mode-common.o check/mode-lowmem.o \
+ cmds/inspect-dump-csum.o
libbtrfs_objects = common/send-stream.o common/send-utils.o kernel-lib/rbtree.o btrfs-list.o \
kernel-lib/radix-tree.o common/extent-cache.o kernel-shared/extent_io.o \
crypto/crc32c.o common/messages.o \
diff --git a/cmds/commands.h b/cmds/commands.h
index 8fa85d6c..350f456a 100644
--- a/cmds/commands.h
+++ b/cmds/commands.h
@@ -140,6 +140,7 @@ DECLARE_COMMAND(check);
DECLARE_COMMAND(scrub);
DECLARE_COMMAND(check);
DECLARE_COMMAND(inspect);
+DECLARE_COMMAND(inspect_dump_csum);
DECLARE_COMMAND(inspect_dump_super);
DECLARE_COMMAND(inspect_dump_tree);
DECLARE_COMMAND(inspect_tree_stats);
diff --git a/cmds/inspect-dump-csum.c b/cmds/inspect-dump-csum.c
new file mode 100644
index 00000000..093f9234
--- /dev/null
+++ b/cmds/inspect-dump-csum.c
@@ -0,0 +1,244 @@
+/*
+ * 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 "kernel-shared/ctree.h"
+#include "kernel-shared/disk-io.h"
+#include "kernel-shared/print-tree.h"
+#include "kernel-shared/transaction.h"
+#include "kernel-lib/list.h"
+#include "common/utils.h"
+#include "cmds/commands.h"
+#include "crypto/crc32c.h"
+#include "common/help.h"
+#include "kernel-shared/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)
+{
+ 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->fs_info->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->fs_info->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->fs_info->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*csum_size)+start_pos) , csum_size);
+ fprintf(stdout, "%x ", tree_csum);
+ if (cnt % 8 == 0)
+ fprintf(stdout, "\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*csum_size)+start_pos), csum_size);
+ fprintf(stdout, "%x ", tree_csum);
+ if (cnt % 8 == 0)
+ fprintf(stdout, "\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){
+ 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;
+ }
+ u16 csum_size = btrfs_super_csum_size(info->csum_root->fs_info->super_copy);
+ 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) / csum_size;
+ path->slots[0]++;
+ itemnum++;
+ path1 = btrfs_alloc_path();
+ ret = btrfs_lookup_csums(NULL,info->csum_root, path1, bytenr, 0,
+ total_csums);
+ 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)
+static int cmd_inspect_dump_csum(const struct cmd_struct *cmd,
+ int argc, char **argv)
+{
+ struct btrfs_fs_info *info;
+ int ret;
+ struct btrfs_path path;
+ struct stat st;
+ char *filename;
+ struct open_ctree_flags ocf = { 0 };
+ ocf.flags = OPEN_CTREE_PARTIAL;
+ ocf.filename = argv[2];
+
+ if (check_argc_exact(argc, 3))
+ usage_unknown_option(cmd, argv);
+
+ filename = argv[1];
+ info = open_ctree_fs_info(&ocf);
+ 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 = btrfs_lookup_extent(info, &path, st.st_ino, 0);
+ ret = close_ctree(info->fs_root);
+ btrfs_close_all_devices();
+
+ return ret;
+}
+DEFINE_SIMPLE_COMMAND(inspect_dump_csum, "dump-csum");
diff --git a/cmds/inspect.c b/cmds/inspect.c
index 76d3936f..574077d3 100644
--- a/cmds/inspect.c
+++ b/cmds/inspect.c
@@ -696,6 +696,7 @@ static const struct cmd_group inspect_cmd_group = {
&cmd_struct_inspect_dump_tree,
&cmd_struct_inspect_dump_super,
&cmd_struct_inspect_tree_stats,
+ &cmd_struct_inspect_dump_csum,
NULL
}
};
--
2.30.2
