Re: [f2fs-dev] [PATCH v2] dump.f2fs: add -I nid to dump inode by scan full disk

[Yufen Yu via Linux-f2fs-devel <linux-f2fs-devel@lists.sourceforge.net>]

On 2022/4/19 10:10, Chao Yu wrote:
> On 2022/4/18 10:43, Yufen Yu via Linux-f2fs-devel wrote:
>> Usage:
>>     dump.f2fs -I [inode nid] /dev/sda
>>
>> This feature can be useful for some bugs caused by system crash.
>> We not only need dump current valid node page, but alse the history
>> data in disk, which can give some clues for status change of the inode.
>>
>> Signed-off-by: Yufen Yu <yuyufen@huawei.com>
>> ---
>>   fsck/dump.c     | 29 +++++++++++++++++++++++++++++
>>   fsck/fsck.h     |  1 +
>>   fsck/main.c     | 14 +++++++++++++-
>>   man/dump.f2fs.8 |  7 +++++++
>>   4 files changed, 50 insertions(+), 1 deletion(-)
>>
>> diff --git a/fsck/dump.c b/fsck/dump.c
>> index fce86c9..7ff0b28 100644
>> --- a/fsck/dump.c
>> +++ b/fsck/dump.c
>> @@ -539,6 +539,35 @@ static bool is_sit_bitmap_set(struct f2fs_sb_info *sbi, u32 blk_addr)
>>               (const char *)se->cur_valid_map) != 0;
>>   }
>> +void dump_node_scan_disk(struct f2fs_sb_info *sbi, nid_t nid)
>> +{
>> +    struct f2fs_node *node_blk;
>> +    pgoff_t blkaddr;
>> +    int ret;
>> +    pgoff_t start_blkaddr = SM_I(sbi)->main_blkaddr;
>> +    pgoff_t end_blkaddr = start_blkaddr +
>> +        (SM_I(sbi)->main_segments << sbi->log_blocks_per_seg);
>> +
>> +    node_blk = calloc(BLOCK_SZ, 1);
>> +    ASSERT(node_blk);
>> +    MSG(0, "Info: scan all nid: %u from block_addr [%lu: %lu]\n",
>> +            nid, start_blkaddr, end_blkaddr);
>> +
>> +    for (blkaddr = start_blkaddr; blkaddr < end_blkaddr; blkaddr++) {
> 
> Shouldn't we skip data segment? otherwise it's possible to encounter data
> collision in traversed data block.
> 

Yeah, skipping data segment can be more strict. But, I am not sure segment type
is correct for some invalid segments. To make things more easy, I just traverse all
main blocks and identify the target inode by checking footer.ino and footer.nid.

Thanks,


> Thanks,
> 
>> +        ret = dev_read_block(node_blk, blkaddr);
>> +        ASSERT(ret >= 0);
>> +        if (le32_to_cpu(node_blk->footer.ino) != nid ||
>> +                le32_to_cpu(node_blk->footer.nid) != nid)
>> +            continue;
>> +        MSG(0, "Info: nid: %u, blkaddr: %lu\n", nid, blkaddr);
>> +        MSG(0, "node_blk.footer.flag [0x%x]\n", le32_to_cpu(node_blk->footer.flag));
>> +        MSG(0, "node_blk.footer.cp_ver [%x]\n", (u32)(cpver_of_node(node_blk)));
>> +        print_inode_info(sbi, node_blk, 0);
>> +    }
>> +
>> +    free(node_blk);
>> +}
>> +
>>   int dump_node(struct f2fs_sb_info *sbi, nid_t nid, int force)
>>   {
>>       struct node_info ni;
>> diff --git a/fsck/fsck.h b/fsck/fsck.h
>> index ce5fffe..0c819f0 100644
>> --- a/fsck/fsck.h
>> +++ b/fsck/fsck.h
>> @@ -262,6 +262,7 @@ struct dump_option {
>>       int start_ssa;
>>       int end_ssa;
>>       int32_t blk_addr;
>> +    nid_t scan_nid;
>>   };
>>   extern void nat_dump(struct f2fs_sb_info *, nid_t, nid_t);
>> diff --git a/fsck/main.c b/fsck/main.c
>> index e4cfdf4..c7ad5ad 100644
>> --- a/fsck/main.c
>> +++ b/fsck/main.c
>> @@ -93,6 +93,7 @@ void dump_usage()
>>       MSG(0, "[options]:\n");
>>       MSG(0, "  -d debug level [default:0]\n");
>>       MSG(0, "  -i inode no (hex)\n");
>> +    MSG(0, "  -I inode no (hex) scan full disk\n");
>>       MSG(0, "  -n [NAT dump nid from #1~#2 (decimal), for all 0~-1]\n");
>>       MSG(0, "  -M show a block map\n");
>>       MSG(0, "  -s [SIT dump segno from #1~#2 (decimal), for all 0~-1]\n");
>> @@ -382,7 +383,7 @@ void f2fs_parse_options(int argc, char *argv[])
>>           }
>>       } else if (!strcmp("dump.f2fs", prog)) {
>>   #ifdef WITH_DUMP
>> -        const char *option_string = "d:i:n:Ms:Sa:b:V";
>> +        const char *option_string = "d:i:I:n:Ms:Sa:b:V";
>>           static struct dump_option dump_opt = {
>>               .nid = 0,    /* default root ino */
>>               .start_nat = -1,
>> @@ -392,6 +393,7 @@ void f2fs_parse_options(int argc, char *argv[])
>>               .start_ssa = -1,
>>               .end_ssa = -1,
>>               .blk_addr = -1,
>> +            .scan_nid = 0,
>>           };
>>           c.func = DUMP;
>> @@ -424,6 +426,14 @@ void f2fs_parse_options(int argc, char *argv[])
>>                       ret = sscanf(optarg, "%x",
>>                               &dump_opt.nid);
>>                   break;
>> +            case 'I':
>> +                if (strncmp(optarg, "0x", 2))
>> +                    ret = sscanf(optarg, "%d",
>> +                            &dump_opt.scan_nid);
>> +                else
>> +                    ret = sscanf(optarg, "%x",
>> +                            &dump_opt.scan_nid);
>> +                break;
>>               case 'n':
>>                   ret = sscanf(optarg, "%d~%d",
>>                               &dump_opt.start_nat,
>> @@ -916,6 +926,8 @@ static void do_dump(struct f2fs_sb_info *sbi)
>>           dump_info_from_blkaddr(sbi, opt->blk_addr);
>>       if (opt->nid)
>>           dump_node(sbi, opt->nid, 0);
>> +    if (opt->scan_nid)
>> +        dump_node_scan_disk(sbi, opt->scan_nid);
>>       print_cp_state(flag);
>> diff --git a/man/dump.f2fs.8 b/man/dump.f2fs.8
>> index 1ddb7fc..94bf5f3 100644
>> --- a/man/dump.f2fs.8
>> +++ b/man/dump.f2fs.8
>> @@ -10,6 +10,10 @@ dump.f2fs \- retrieve directory and file entries from an F2FS-formated image
>>   .I inode number
>>   ]
>>   [
>> +.B \-I
>> +.I inode number
>> +]
>> +[
>>   .B \-n
>>   .I NAT range
>>   ]
>> @@ -52,6 +56,9 @@ is 0 on success and -1 on failure.
>>   .BI \-i " inode number"
>>   Specify an inode number to dump out.
>>   .TP
>> +.BI \-I " inode number"
>> +Specify an inode number and scan full disk to dump out, include history inode block
>> +.TP
>>   .BI \-n " NAT range"
>>   Specify a range presented by nids to dump NAT entries.
>>   .TP
> .


_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel