Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "The major change this cycle is deleting ext4's copy of the file system
  encryption code and switching things over to using the copies in
  fs/crypto.  I've updated the MAINTAINERS file to add an entry for
  fs/crypto listing Jaeguk Kim and myself as the maintainers.

  There are also a number of bug fixes, most notably for some problems
  found by American Fuzzy Lop (AFL) courtesy of Vegard Nossum.  Also
  fixed is a writeback deadlock detected by generic/130, and some
  potential races in the metadata checksum code"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits)
  ext4: verify extent header depth
  ext4: short-cut orphan cleanup on error
  ext4: fix reference counting bug on block allocation error
  MAINTAINRES: fs-crypto maintainers update
  ext4 crypto: migrate into vfs's crypto engine
  ext2: fix filesystem deadlock while reading corrupted xattr block
  ext4: fix project quota accounting without quota limits enabled
  ext4: validate s_reserved_gdt_blocks on mount
  ext4: remove unused page_idx
  ext4: don't call ext4_should_journal_data() on the journal inode
  ext4: Fix WARN_ON_ONCE in ext4_commit_super()
  ext4: fix deadlock during page writeback
  ext4: correct error value of function verifying dx checksum
  ext4: avoid modifying checksum fields directly during checksum verification
  ext4: check for extents that wrap around
  jbd2: make journal y2038 safe
  jbd2: track more dependencies on transaction commit
  jbd2: move lockdep tracking to journal_s
  jbd2: move lockdep instrumentation for jbd2 handles
  ext4: respect the nobarrier mount option in nojournal mode
  ...

1 files changed, 19 insertions, 4 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index efb232c5f668..dfaa1f4dcb0c 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -491,10 +491,6 @@ struct jbd2_journal_handle
 
 	unsigned long		h_start_jiffies;
 	unsigned int		h_requested_credits;
-
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-	struct lockdep_map	h_lockdep_map;
-#endif
 };
 
 
@@ -793,6 +789,7 @@ jbd2_time_diff(unsigned long start, unsigned long end)
  * @j_proc_entry: procfs entry for the jbd statistics directory
  * @j_stats: Overall statistics
  * @j_private: An opaque pointer to fs-private information.
+ * @j_trans_commit_map: Lockdep entity to track transaction commit dependencies
  */
 
 struct journal_s
@@ -1035,8 +1032,26 @@ struct journal_s
 
 	/* Precomputed journal UUID checksum for seeding other checksums */
 	__u32 j_csum_seed;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	/*
+	 * Lockdep entity to track transaction commit dependencies. Handles
+	 * hold this "lock" for read, when we wait for commit, we acquire the
+	 * "lock" for writing. This matches the properties of jbd2 journalling
+	 * where the running transaction has to wait for all handles to be
+	 * dropped to commit that transaction and also acquiring a handle may
+	 * require transaction commit to finish.
+	 */
+	struct lockdep_map	j_trans_commit_map;
+#endif
 };
 
+#define jbd2_might_wait_for_commit(j) \
+	do { \
+		rwsem_acquire(&j->j_trans_commit_map, 0, 0, _THIS_IP_); \
+		rwsem_release(&j->j_trans_commit_map, 1, _THIS_IP_); \
+	} while (0)
+
 /* journal feature predicate functions */
 #define JBD2_FEATURE_COMPAT_FUNCS(name, flagname) \
 static inline bool jbd2_has_feature_##name(journal_t *j) \