jbd2: improve error messages for inconsistent journal heads

Fix up error messages printed when the transaction pointers in a
journal head are inconsistent.  This improves the error messages which
are printed when running xfstests generic/068 in data=journal mode.
See the bug report at: https://bugzilla.kernel.org/show_bug.cgi?id=60786

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

2 files changed, 24 insertions, 19 deletions

diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index 3fe29de832c8..c3fb607413ed 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -259,6 +259,16 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
                 if (WARN_ON_ONCE(err)) {
                         ext4_journal_abort_handle(where, line, __func__, bh,
                                                   handle, err);
+                        if (inode == NULL) {
+                                pr_err("EXT4: jbd2_journal_dirty_metadata "
+                                       "failed: handle type %u started at "
+                                       "line %u, credits %u/%u, errcode %d",
+                                       handle->h_type,
+                                       handle->h_line_no,
+                                       handle->h_requested_credits,
+                                       handle->h_buffer_credits, err);
+                                return err;
+                        }
                         ext4_error_inode(inode, where, line,
                                          bh->b_blocknr,
                                          "journal_dirty_metadata failed: "
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index d999b1f6847c..38cfcf5f6fce 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1313,7 +1313,7 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
                              journal->j_running_transaction)) {
                         printk(KERN_ERR "JBD2: %s: "
                                "jh->b_transaction (%llu, %p, %u) != "
-                               "journal->j_running_transaction (%p, %u)",
+                               "journal->j_running_transaction (%p, %u)\n",
                                journal->j_devname,
                                (unsigned long long) bh->b_blocknr,
                                jh->b_transaction,
@@ -1336,30 +1336,25 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
          */
         if (jh->b_transaction != transaction) {
                 JBUFFER_TRACE(jh, "already on other transaction");
-                if (unlikely(jh->b_transaction !=
-                             journal->j_committing_transaction)) {
-                        printk(KERN_ERR "JBD2: %s: "
-                               "jh->b_transaction (%llu, %p, %u) != "
-                               "journal->j_committing_transaction (%p, %u)",
+                if (unlikely(((jh->b_transaction !=
+                               journal->j_committing_transaction)) ||
+                             (jh->b_next_transaction != transaction))) {
+                        printk(KERN_ERR "jbd2_journal_dirty_metadata: %s: "
+                               "bad jh for block %llu: "
+                               "transaction (%p, %u), "
+                               "jh->b_transaction (%p, %u), "
+                               "jh->b_next_transaction (%p, %u), jlist %u\n",
                                journal->j_devname,
                                (unsigned long long) bh->b_blocknr,
+                               transaction, transaction->t_tid,
                                jh->b_transaction,
-                               jh->b_transaction ? jh->b_transaction->t_tid : 0,
-                               journal->j_committing_transaction,
-                               journal->j_committing_transaction ?
-                               journal->j_committing_transaction->t_tid : 0);
-                        ret = -EINVAL;
-                }
-                if (unlikely(jh->b_next_transaction != transaction)) {
-                        printk(KERN_ERR "JBD2: %s: "
-                               "jh->b_next_transaction (%llu, %p, %u) != "
-                               "transaction (%p, %u)",
-                               journal->j_devname,
-                               (unsigned long long) bh->b_blocknr,
+                               jh->b_transaction ?
+                               jh->b_transaction->t_tid : 0,
                                jh->b_next_transaction,
                                jh->b_next_transaction ?
                                jh->b_next_transaction->t_tid : 0,
-                               transaction, transaction->t_tid);
+                               jh->b_jlist);
+                        WARN_ON(1);
                         ret = -EINVAL;
                 }
                 /* And this case is illegal: we can't reuse another