Merge tag 'xfs-5.14-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "Most of the work this cycle has been on refactoring various parts of
  the codebase. The biggest non-cleanup changes are (1) reducing the
  number of cache flushes sent when writing the log; (2) a substantial
  number of log recovery fixes; and (3) I started accepting pull
  requests from contributors if the commits in their branches match
  what's been sent to the list.

  For a week or so I /had/ staged a major cleanup of the logging code
  from Dave Chinner, but it exposed so many lurking bugs in other parts
  of the logging and log recovery code that I decided to defer that
  patchset until we can address those latent bugs.

  Larger cleanups this time include walking the incore inode cache (me)
  and rework of the extended attribute code (Allison) to prepare it for
  adding logged xattr updates (and directory tree parent pointers) in
  future releases.

  Summary:

   - Refactor the buffer cache to use bulk page allocation

   - Convert agnumber-based AG iteration to walk per-AG structures

   - Clean up some unit conversions and other code warts

   - Reduce spinlock contention in the directio fastpath

   - Collapse all the inode cache walks into a single function

   - Remove indirect function calls from the inode cache walk code

   - Dramatically reduce the number of cache flushes sent when writing
     log buffers

   - Preserve inode sickness reports for longer

   - Rename xfs_eofblocks since it controls inode cache walks

   - Refactor the extended attribute code to prepare it for the addition
     of log intent items to make xattrs fully transactional

   - A few fixes to earlier large patchsets

   - Log recovery fixes so that we don't accidentally mark the log clean
     when log intent recovery fails

   - Fix some latent SOB errors

   - Clean up shutdown messages that get logged to dmesg

   - Fix a regression in the online shrink code

   - Fix a UAF in the buffer logging code if the fs goes offline

   - Fix uninitialized error variables

   - Fix a UAF in the CIL when commited log item callbacks race with a
     shutdown

   - Fix a bug where the CIL could hang trying to push part of the log
     ring buffer that hasn't been filled yet"

* tag 'xfs-5.14-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (102 commits)
  xfs: don't wait on future iclogs when pushing the CIL
  xfs: Fix a CIL UAF by getting get rid of the iclog callback lock
  xfs: remove callback dequeue loop from xlog_state_do_iclog_callbacks
  xfs: don't nest icloglock inside ic_callback_lock
  xfs: Initialize error in xfs_attr_remove_iter
  xfs: fix endianness issue in xfs_ag_shrink_space
  xfs: remove dead stale buf unpin handling code
  xfs: hold buffer across unpin and potential shutdown processing
  xfs: force the log offline when log intent item recovery fails
  xfs: fix log intent recovery ENOSPC shutdowns when inactivating inodes
  xfs: shorten the shutdown messages to a single line
  xfs: print name of function causing fs shutdown instead of hex pointer
  xfs: fix type mismatches in the inode reclaim functions
  xfs: separate primary inode selection criteria in xfs_iget_cache_hit
  xfs: refactor the inode recycling code
  xfs: add iclog state trace events
  xfs: xfs_log_force_lsn isn't passed a LSN
  xfs: Fix CIL throttle hang when CIL space used going backwards
  xfs: journal IO cache flush reductions
  xfs: remove need_start_rec parameter from xlog_write()
  ...

1 files changed, 116 insertions, 157 deletions

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index a002425377b5..36fa2650b081 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -502,6 +502,7 @@ __xlog_state_release_iclog(
 		iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn);
 		xlog_verify_tail_lsn(log, iclog, tail_lsn);
 		/* cycle incremented when incrementing curr_block */
+		trace_xlog_iclog_syncing(iclog, _RET_IP_);
 		return true;
 	}
 
@@ -513,13 +514,14 @@ __xlog_state_release_iclog(
  * Flush iclog to disk if this is the last reference to the given iclog and the
  * it is in the WANT_SYNC state.
  */
-static int
+int
 xlog_state_release_iclog(
 	struct xlog		*log,
 	struct xlog_in_core	*iclog)
 {
 	lockdep_assert_held(&log->l_icloglock);
 
+	trace_xlog_iclog_release(iclog, _RET_IP_);
 	if (iclog->ic_state == XLOG_STATE_IOERROR)
 		return -EIO;
 
@@ -533,23 +535,6 @@ xlog_state_release_iclog(
 	return 0;
 }
 
-void
-xfs_log_release_iclog(
-	struct xlog_in_core	*iclog)
-{
-	struct xlog		*log = iclog->ic_log;
-	bool			sync = false;
-
-	if (atomic_dec_and_lock(&iclog->ic_refcnt, &log->l_icloglock)) {
-		if (iclog->ic_state != XLOG_STATE_IOERROR)
-			sync = __xlog_state_release_iclog(log, iclog);
-		spin_unlock(&log->l_icloglock);
-	}
-
-	if (sync)
-		xlog_sync(log, iclog);
-}
-
 /*
  * Mount a log filesystem
  *
@@ -770,6 +755,9 @@ xfs_log_mount_finish(
 	if (readonly)
 		mp->m_flags |= XFS_MOUNT_RDONLY;
 
+	/* Make sure the log is dead if we're returning failure. */
+	ASSERT(!error || (mp->m_log->l_flags & XLOG_IO_ERROR));
+
 	return error;
 }
 
@@ -786,16 +774,19 @@ xfs_log_mount_cancel(
 }
 
 /*
- * Wait for the iclog to be written disk, or return an error if the log has been
- * shut down.
+ * Wait for the iclog and all prior iclogs to be written disk as required by the
+ * log force state machine. Waiting on ic_force_wait ensures iclog completions
+ * have been ordered and callbacks run before we are woken here, hence
+ * guaranteeing that all the iclogs up to this one are on stable storage.
  */
-static int
+int
 xlog_wait_on_iclog(
 	struct xlog_in_core	*iclog)
 		__releases(iclog->ic_log->l_icloglock)
 {
 	struct xlog		*log = iclog->ic_log;
 
+	trace_xlog_iclog_wait_on(iclog, _RET_IP_);
 	if (!XLOG_FORCED_SHUTDOWN(log) &&
 	    iclog->ic_state != XLOG_STATE_ACTIVE &&
 	    iclog->ic_state != XLOG_STATE_DIRTY) {
@@ -818,9 +809,7 @@ xlog_wait_on_iclog(
 static int
 xlog_write_unmount_record(
 	struct xlog		*log,
-	struct xlog_ticket	*ticket,
-	xfs_lsn_t		*lsn,
-	uint			flags)
+	struct xlog_ticket	*ticket)
 {
 	struct xfs_unmount_log_format ulf = {
 		.magic = XLOG_UNMOUNT_TYPE,
@@ -837,7 +826,15 @@ xlog_write_unmount_record(
 
 	/* account for space used by record data */
 	ticket->t_curr_res -= sizeof(ulf);
-	return xlog_write(log, &vec, ticket, lsn, NULL, flags, false);
+
+	/*
+	 * For external log devices, we need to flush the data device cache
+	 * first to ensure all metadata writeback is on stable storage before we
+	 * stamp the tail LSN into the unmount record.
+	 */
+	if (log->l_targ != log->l_mp->m_ddev_targp)
+		blkdev_issue_flush(log->l_targ->bt_bdev);
+	return xlog_write(log, &vec, ticket, NULL, NULL, XLOG_UNMOUNT_TRANS);
 }
 
 /*
@@ -851,15 +848,13 @@ xlog_unmount_write(
 	struct xfs_mount	*mp = log->l_mp;
 	struct xlog_in_core	*iclog;
 	struct xlog_ticket	*tic = NULL;
-	xfs_lsn_t		lsn;
-	uint			flags = XLOG_UNMOUNT_TRANS;
 	int			error;
 
 	error = xfs_log_reserve(mp, 600, 1, &tic, XFS_LOG, 0);
 	if (error)
 		goto out_err;
 
-	error = xlog_write_unmount_record(log, tic, &lsn, flags);
+	error = xlog_write_unmount_record(log, tic);
 	/*
 	 * At this point, we're umounting anyway, so there's no point in
 	 * transitioning log state to IOERROR. Just continue...
@@ -876,6 +871,11 @@ out_err:
 	else
 		ASSERT(iclog->ic_state == XLOG_STATE_WANT_SYNC ||
 		       iclog->ic_state == XLOG_STATE_IOERROR);
+	/*
+	 * Ensure the journal is fully flushed and on stable storage once the
+	 * iclog containing the unmount record is written.
+	 */
+	iclog->ic_flags |= (XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA);
 	error = xlog_state_release_iclog(log, iclog);
 	xlog_wait_on_iclog(iclog);
 
@@ -1401,6 +1401,11 @@ xlog_alloc_log(
 	xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0);
 	log->l_curr_cycle  = 1;	    /* 0 is bad since this is initial value */
 
+	if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1)
+		log->l_iclog_roundoff = mp->m_sb.sb_logsunit;
+	else
+		log->l_iclog_roundoff = BBSIZE;
+
 	xlog_grant_head_init(&log->l_reserve_head);
 	xlog_grant_head_init(&log->l_write_head);
 
@@ -1479,7 +1484,6 @@ xlog_alloc_log(
 		iclog->ic_state = XLOG_STATE_ACTIVE;
 		iclog->ic_log = log;
 		atomic_set(&iclog->ic_refcnt, 0);
-		spin_lock_init(&iclog->ic_callback_lock);
 		INIT_LIST_HEAD(&iclog->ic_callbacks);
 		iclog->ic_datap = (char *)iclog->ic_data + log->l_iclog_hsize;
 
@@ -1546,8 +1550,7 @@ xlog_commit_record(
 	if (XLOG_FORCED_SHUTDOWN(log))
 		return -EIO;
 
-	error = xlog_write(log, &vec, ticket, lsn, iclog, XLOG_COMMIT_TRANS,
-			   false);
+	error = xlog_write(log, &vec, ticket, lsn, iclog, XLOG_COMMIT_TRANS);
 	if (error)
 		xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
 	return error;
@@ -1753,10 +1756,10 @@ xlog_write_iclog(
 	struct xlog		*log,
 	struct xlog_in_core	*iclog,
 	uint64_t		bno,
-	unsigned int		count,
-	bool			need_flush)
+	unsigned int		count)
 {
 	ASSERT(bno < log->l_logBBsize);
+	trace_xlog_iclog_write(iclog, _RET_IP_);
 
 	/*
 	 * We lock the iclogbufs here so that we can serialise against I/O
@@ -1792,10 +1795,12 @@ xlog_write_iclog(
 	 * writeback throttle from throttling log writes behind background
 	 * metadata writeback and causing priority inversions.
 	 */
-	iclog->ic_bio.bi_opf = REQ_OP_WRITE | REQ_META | REQ_SYNC |
-				REQ_IDLE | REQ_FUA;
-	if (need_flush)
+	iclog->ic_bio.bi_opf = REQ_OP_WRITE | REQ_META | REQ_SYNC | REQ_IDLE;
+	if (iclog->ic_flags & XLOG_ICL_NEED_FLUSH)
 		iclog->ic_bio.bi_opf |= REQ_PREFLUSH;
+	if (iclog->ic_flags & XLOG_ICL_NEED_FUA)
+		iclog->ic_bio.bi_opf |= REQ_FUA;
+	iclog->ic_flags &= ~(XLOG_ICL_NEED_FLUSH | XLOG_ICL_NEED_FUA);
 
 	if (xlog_map_iclog_data(&iclog->ic_bio, iclog->ic_data, count)) {
 		xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
@@ -1854,29 +1859,15 @@ xlog_calc_iclog_size(
 	uint32_t		*roundoff)
 {
 	uint32_t		count_init, count;
-	bool			use_lsunit;
-
-	use_lsunit = xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
-			log->l_mp->m_sb.sb_logsunit > 1;
 
 	/* Add for LR header */
 	count_init = log->l_iclog_hsize + iclog->ic_offset;
+	count = roundup(count_init, log->l_iclog_roundoff);
 
-	/* Round out the log write size */
-	if (use_lsunit) {
-		/* we have a v2 stripe unit to use */
-		count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init));
-	} else {
-		count = BBTOB(BTOBB(count_init));
-	}
-
-	ASSERT(count >= count_init);
 	*roundoff = count - count_init;
 
-	if (use_lsunit)
-		ASSERT(*roundoff < log->l_mp->m_sb.sb_logsunit);
-	else
-		ASSERT(*roundoff < BBTOB(1));
+	ASSERT(count >= count_init);
+	ASSERT(*roundoff < log->l_iclog_roundoff);
 	return count;
 }
 
@@ -1912,9 +1903,9 @@ xlog_sync(
 	unsigned int		roundoff;       /* roundoff to BB or stripe */
 	uint64_t		bno;
 	unsigned int		size;
-	bool			need_flush = true, split = false;
 
 	ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
+	trace_xlog_iclog_sync(iclog, _RET_IP_);
 
 	count = xlog_calc_iclog_size(log, iclog, &roundoff);
 
@@ -1937,10 +1928,8 @@ xlog_sync(
 	bno = BLOCK_LSN(be64_to_cpu(iclog->ic_header.h_lsn));
 
 	/* Do we need to split this write into 2 parts? */
-	if (bno + BTOBB(count) > log->l_logBBsize) {
+	if (bno + BTOBB(count) > log->l_logBBsize)
 		xlog_split_iclog(log, &iclog->ic_header, bno, count);
-		split = true;
-	}
 
 	/* calculcate the checksum */
 	iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header,
@@ -1961,22 +1950,8 @@ xlog_sync(
 			 be64_to_cpu(iclog->ic_header.h_lsn));
 	}
 #endif
-
-	/*
-	 * Flush the data device before flushing the log to make sure all meta
-	 * data written back from the AIL actually made it to disk before
-	 * stamping the new log tail LSN into the log buffer.  For an external
-	 * log we need to issue the flush explicitly, and unfortunately
-	 * synchronously here; for an internal log we can simply use the block
-	 * layer state machine for preflushes.
-	 */
-	if (log->l_targ != log->l_mp->m_ddev_targp || split) {
-		xfs_blkdev_issue_flush(log->l_mp->m_ddev_targp);
-		need_flush = false;
-	}
-
 	xlog_verify_iclog(log, iclog, count);
-	xlog_write_iclog(log, iclog, bno, count, need_flush);
+	xlog_write_iclog(log, iclog, bno, count);
 }
 
 /*
@@ -2158,13 +2133,16 @@ static int
 xlog_write_calc_vec_length(
 	struct xlog_ticket	*ticket,
 	struct xfs_log_vec	*log_vector,
-	bool			need_start_rec)
+	uint			optype)
 {
 	struct xfs_log_vec	*lv;
-	int			headers = need_start_rec ? 1 : 0;
+	int			headers = 0;
 	int			len = 0;
 	int			i;
 
+	if (optype & XLOG_START_TRANS)
+		headers++;
+
 	for (lv = log_vector; lv; lv = lv->lv_next) {
 		/* we don't write ordered log vectors */
 		if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED)
@@ -2384,8 +2362,7 @@ xlog_write(
 	struct xlog_ticket	*ticket,
 	xfs_lsn_t		*start_lsn,
 	struct xlog_in_core	**commit_iclog,
-	uint			flags,
-	bool			need_start_rec)
+	uint			optype)
 {
 	struct xlog_in_core	*iclog = NULL;
 	struct xfs_log_vec	*lv = log_vector;
@@ -2413,8 +2390,9 @@ xlog_write(
 		xfs_force_shutdown(log->l_mp, SHUTDOWN_LOG_IO_ERROR);
 	}
 
-	len = xlog_write_calc_vec_length(ticket, log_vector, need_start_rec);
-	*start_lsn = 0;
+	len = xlog_write_calc_vec_length(ticket, log_vector, optype);
+	if (start_lsn)
+		*start_lsn = 0;
 	while (lv && (!lv->lv_niovecs || index < lv->lv_niovecs)) {
 		void		*ptr;
 		int		log_offset;
@@ -2427,8 +2405,8 @@ xlog_write(
 		ASSERT(log_offset <= iclog->ic_size - 1);
 		ptr = iclog->ic_datap + log_offset;
 
-		/* start_lsn is the first lsn written to. That's all we need. */
-		if (!*start_lsn)
+		/* Start_lsn is the first lsn written to. */
+		if (start_lsn && !*start_lsn)
 			*start_lsn = be64_to_cpu(iclog->ic_header.h_lsn);
 
 		/*
@@ -2441,6 +2419,7 @@ xlog_write(
 			int			copy_len;
 			int			copy_off;
 			bool			ordered = false;
+			bool			wrote_start_rec = false;
 
 			/* ordered log vectors have no regions to write */
 			if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) {
@@ -2458,13 +2437,15 @@ xlog_write(
 			 * write a start record. Only do this for the first
 			 * iclog we write to.
 			 */
-			if (need_start_rec) {
+			if (optype & XLOG_START_TRANS) {
 				xlog_write_start_rec(ptr, ticket);
 				xlog_write_adv_cnt(&ptr, &len, &log_offset,
 						sizeof(struct xlog_op_header));
+				optype &= ~XLOG_START_TRANS;
+				wrote_start_rec = true;
 			}
 
-			ophdr = xlog_write_setup_ophdr(log, ptr, ticket, flags);
+			ophdr = xlog_write_setup_ophdr(log, ptr, ticket, optype);
 			if (!ophdr)
 				return -EIO;
 
@@ -2495,14 +2476,13 @@ xlog_write(
 			}
 			copy_len += sizeof(struct xlog_op_header);
 			record_cnt++;
-			if (need_start_rec) {
+			if (wrote_start_rec) {
 				copy_len += sizeof(struct xlog_op_header);
 				record_cnt++;
-				need_start_rec = false;
 			}
 			data_cnt += contwr ? copy_len : 0;
 
-			error = xlog_write_copy_finish(log, iclog, flags,
+			error = xlog_write_copy_finish(log, iclog, optype,
 						       &record_cnt, &data_cnt,
 						       &partial_copy,
 						       &partial_copy_len,
@@ -2546,7 +2526,7 @@ next_lv:
 	spin_lock(&log->l_icloglock);
 	xlog_state_finish_copy(log, iclog, record_cnt, data_cnt);
 	if (commit_iclog) {
-		ASSERT(flags & XLOG_COMMIT_TRANS);
+		ASSERT(optype & XLOG_COMMIT_TRANS);
 		*commit_iclog = iclog;
 	} else {
 		error = xlog_state_release_iclog(log, iclog);
@@ -2562,6 +2542,7 @@ xlog_state_activate_iclog(
 	int			*iclogs_changed)
 {
 	ASSERT(list_empty_careful(&iclog->ic_callbacks));
+	trace_xlog_iclog_activate(iclog, _RET_IP_);
 
 	/*
 	 * If the number of ops in this iclog indicate it just contains the
@@ -2652,6 +2633,8 @@ xlog_state_clean_iclog(
 {
 	int			iclogs_changed = 0;
 
+	trace_xlog_iclog_clean(dirty_iclog, _RET_IP_);
+
 	dirty_iclog->ic_state = XLOG_STATE_DIRTY;
 
 	xlog_state_activate_iclogs(log, &iclogs_changed);
@@ -2711,6 +2694,7 @@ xlog_state_set_callback(
 	struct xlog_in_core	*iclog,
 	xfs_lsn_t		header_lsn)
 {
+	trace_xlog_iclog_callback(iclog, _RET_IP_);
 	iclog->ic_state = XLOG_STATE_CALLBACK;
 
 	ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn),
@@ -2776,43 +2760,6 @@ xlog_state_iodone_process_iclog(
 	}
 }
 
-/*
- * Keep processing entries in the iclog callback list until we come around and
- * it is empty.  We need to atomically see that the list is empty and change the
- * state to DIRTY so that we don't miss any more callbacks being added.
- *
- * This function is called with the icloglock held and returns with it held. We
- * drop it while running callbacks, however, as holding it over thousands of
- * callbacks is unnecessary and causes excessive contention if we do.
- */
-static void
-xlog_state_do_iclog_callbacks(
-	struct xlog		*log,
-	struct xlog_in_core	*iclog)
-		__releases(&log->l_icloglock)
-		__acquires(&log->l_icloglock)
-{
-	spin_unlock(&log->l_icloglock);
-	spin_lock(&iclog->ic_callback_lock);
-	while (!list_empty(&iclog->ic_callbacks)) {
-		LIST_HEAD(tmp);
-
-		list_splice_init(&iclog->ic_callbacks, &tmp);
-
-		spin_unlock(&iclog->ic_callback_lock);
-		xlog_cil_process_committed(&tmp);
-		spin_lock(&iclog->ic_callback_lock);
-	}
-
-	/*
-	 * Pick up the icloglock while still holding the callback lock so we
-	 * serialise against anyone trying to add more callbacks to this iclog
-	 * now we've finished processing.
-	 */
-	spin_lock(&log->l_icloglock);
-	spin_unlock(&iclog->ic_callback_lock);
-}
-
 STATIC void
 xlog_state_do_callback(
 	struct xlog		*log)
@@ -2841,6 +2788,8 @@ xlog_state_do_callback(
 		repeats++;
 
 		do {
+			LIST_HEAD(cb_list);
+
 			if (xlog_state_iodone_process_iclog(log, iclog,
 							&ioerror))
 				break;
@@ -2850,13 +2799,15 @@ xlog_state_do_callback(
 				iclog = iclog->ic_next;
 				continue;
 			}
+			list_splice_init(&iclog->ic_callbacks, &cb_list);
+			spin_unlock(&log->l_icloglock);
 
-			/*
-			 * Running callbacks will drop the icloglock which means
-			 * we'll have to run at least one more complete loop.
-			 */
+			trace_xlog_iclog_callbacks_start(iclog, _RET_IP_);
+			xlog_cil_process_committed(&cb_list);
+			trace_xlog_iclog_callbacks_done(iclog, _RET_IP_);
 			cycled_icloglock = true;
-			xlog_state_do_iclog_callbacks(log, iclog);
+
+			spin_lock(&log->l_icloglock);
 			if (XLOG_FORCED_SHUTDOWN(log))
 				wake_up_all(&iclog->ic_force_wait);
 			else
@@ -2902,6 +2853,7 @@ xlog_state_done_syncing(
 
 	spin_lock(&log->l_icloglock);
 	ASSERT(atomic_read(&iclog->ic_refcnt) == 0);
+	trace_xlog_iclog_sync_done(iclog, _RET_IP_);
 
 	/*
 	 * If we got an error, either on the first buffer, or in the case of
@@ -2975,6 +2927,8 @@ restart:
 	atomic_inc(&iclog->ic_refcnt);	/* prevents sync */
 	log_offset = iclog->ic_offset;
 
+	trace_xlog_iclog_get_space(iclog, _RET_IP_);
+
 	/* On the 1st write to an iclog, figure out lsn.  This works
 	 * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are
 	 * committing to.  If the offset is set, that's how many blocks
@@ -3140,6 +3094,7 @@ xlog_state_switch_iclogs(
 {
 	ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE);
 	assert_spin_locked(&log->l_icloglock);
+	trace_xlog_iclog_switch(iclog, _RET_IP_);
 
 	if (!eventual_size)
 		eventual_size = iclog->ic_offset;
@@ -3152,9 +3107,8 @@ xlog_state_switch_iclogs(
 	log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize);
 
 	/* Round up to next log-sunit */
-	if (xfs_sb_version_haslogv2(&log->l_mp->m_sb) &&
-	    log->l_mp->m_sb.sb_logsunit > 1) {
-		uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit);
+	if (log->l_iclog_roundoff > BBSIZE) {
+		uint32_t sunit_bb = BTOBB(log->l_iclog_roundoff);
 		log->l_curr_block = roundup(log->l_curr_block, sunit_bb);
 	}
 
@@ -3223,6 +3177,8 @@ xfs_log_force(
 	if (iclog->ic_state == XLOG_STATE_IOERROR)
 		goto out_error;
 
+	trace_xlog_iclog_force(iclog, _RET_IP_);
+
 	if (iclog->ic_state == XLOG_STATE_DIRTY ||
 	    (iclog->ic_state == XLOG_STATE_ACTIVE &&
 	     atomic_read(&iclog->ic_refcnt) == 0 && iclog->ic_offset == 0)) {
@@ -3281,14 +3237,13 @@ out_error:
 }
 
 static int
-__xfs_log_force_lsn(
-	struct xfs_mount	*mp,
+xlog_force_lsn(
+	struct xlog		*log,
 	xfs_lsn_t		lsn,
 	uint			flags,
 	int			*log_flushed,
 	bool			already_slept)
 {
-	struct xlog		*log = mp->m_log;
 	struct xlog_in_core	*iclog;
 
 	spin_lock(&log->l_icloglock);
@@ -3297,6 +3252,7 @@ __xfs_log_force_lsn(
 		goto out_error;
 
 	while (be64_to_cpu(iclog->ic_header.h_lsn) != lsn) {
+		trace_xlog_iclog_force_lsn(iclog, _RET_IP_);
 		iclog = iclog->ic_next;
 		if (iclog == log->l_iclog)
 			goto out_unlock;
@@ -3321,8 +3277,6 @@ __xfs_log_force_lsn(
 		if (!already_slept &&
 		    (iclog->ic_prev->ic_state == XLOG_STATE_WANT_SYNC ||
 		     iclog->ic_prev->ic_state == XLOG_STATE_SYNCING)) {
-			XFS_STATS_INC(mp, xs_log_force_sleep);
-
 			xlog_wait(&iclog->ic_prev->ic_write_wait,
 					&log->l_icloglock);
 			return -EAGAIN;
@@ -3360,25 +3314,29 @@ out_error:
  * to disk, that thread will wake up all threads waiting on the queue.
  */
 int
-xfs_log_force_lsn(
+xfs_log_force_seq(
 	struct xfs_mount	*mp,
-	xfs_lsn_t		lsn,
+	xfs_csn_t		seq,
 	uint			flags,
 	int			*log_flushed)
 {
+	struct xlog		*log = mp->m_log;
+	xfs_lsn_t		lsn;
 	int			ret;
-	ASSERT(lsn != 0);
+	ASSERT(seq != 0);
 
 	XFS_STATS_INC(mp, xs_log_force);
-	trace_xfs_log_force(mp, lsn, _RET_IP_);
+	trace_xfs_log_force(mp, seq, _RET_IP_);
 
-	lsn = xlog_cil_force_lsn(mp->m_log, lsn);
+	lsn = xlog_cil_force_seq(log, seq);
 	if (lsn == NULLCOMMITLSN)
 		return 0;
 
-	ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, false);
-	if (ret == -EAGAIN)
-		ret = __xfs_log_force_lsn(mp, lsn, flags, log_flushed, true);
+	ret = xlog_force_lsn(log, lsn, flags, log_flushed, false);
+	if (ret == -EAGAIN) {
+		XFS_STATS_INC(mp, xs_log_force_sleep);
+		ret = xlog_force_lsn(log, lsn, flags, log_flushed, true);
+	}
 	return ret;
 }
 
@@ -3407,12 +3365,11 @@ xfs_log_ticket_get(
  * Figure out the total log space unit (in bytes) that would be
  * required for a log ticket.
  */
-int
-xfs_log_calc_unit_res(
-	struct xfs_mount	*mp,
+static int
+xlog_calc_unit_res(
+	struct xlog		*log,
 	int			unit_bytes)
 {
-	struct xlog		*log = mp->m_log;
 	int			iclog_space;
 	uint			num_headers;
 
@@ -3488,18 +3445,20 @@ xfs_log_calc_unit_res(
 	/* for commit-rec LR header - note: padding will subsume the ophdr */
 	unit_bytes += log->l_iclog_hsize;
 
-	/* for roundoff padding for transaction data and one for commit record */
-	if (xfs_sb_version_haslogv2(&mp->m_sb) && mp->m_sb.sb_logsunit > 1) {
-		/* log su roundoff */
-		unit_bytes += 2 * mp->m_sb.sb_logsunit;
-	} else {
-		/* BB roundoff */
-		unit_bytes += 2 * BBSIZE;
-        }
+	/* roundoff padding for transaction data and one for commit record */
+	unit_bytes += 2 * log->l_iclog_roundoff;
 
 	return unit_bytes;
 }
 
+int
+xfs_log_calc_unit_res(
+	struct xfs_mount	*mp,
+	int			unit_bytes)
+{
+	return xlog_calc_unit_res(mp->m_log, unit_bytes);
+}
+
 /*
  * Allocate and initialise a new log ticket.
  */
@@ -3516,7 +3475,7 @@ xlog_ticket_alloc(
 
 	tic = kmem_cache_zalloc(xfs_log_ticket_zone, GFP_NOFS | __GFP_NOFAIL);
 
-	unit_res = xfs_log_calc_unit_res(log->l_mp, unit_bytes);
+	unit_res = xlog_calc_unit_res(log, unit_bytes);
 
 	atomic_set(&tic->t_ref, 1);
 	tic->t_task		= current;