@@ -740,6 +740,18 @@ static void dump_descriptor_block(FILE *out_file,
} while (!(tag_flags & JBD2_FLAG_LAST_TAG));
+ /* When a tail-to-head reversal occurs, we need to check whether
+ * there is a log that starts from the beginning again.
+ */
+ if (*blockp > blocknr) {
+ journal_header_t first_header = {0};
+
+ read_journal_block("logdump", source, blocksize,
+ (char *)&first_header, sizeof(journal_header_t));
+ if ((be32_to_cpu(first_header.h_magic) == JBD2_MAGIC_NUMBER) &&
+ (be32_to_cpu(first_header.h_blocktype) == JBD2_DESCRIPTOR_BLOCK))
+ blocknr = 1;
+ }
*blockp = blocknr;
}
When logs are dumped, if the last description block in the journal area contains the first journal block as the data block, logs may be repeatedly printed or not completely printed. After the journal replay, we always restart logging from the first journal block. In this case, there are the following two cases: 1) If start == first, the first block is always skipped due to reversal. Therefore, the condition (blocknr == first_transaction_blocknr) for determining repeated printing does not take effect. As a result, logs are repeatedly printed. 2) If start != first, we will traverse backwards from the first non-data block after the last journal data block in the last description block, and the logs from the first journal block to this block will not be printed. That is, the dump log is incomplete. To solve this problem, we only need to check the type of the first log block when reversal occurs. If it is a non-log data block, we should continue to dump directly from the first block. Signed-off-by: Baokun Li <libaokun1@huawei.com> --- debugfs/logdump.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)