On Thu, Feb 25, 2021 at 07:27:20PM +0100, Christoph Hellwig wrote:

quoted

+			if (optype && index) {
+				optype &= ~XLOG_START_TRANS;
+			} else if (partial_copy) {
                                 ophdr = xlog_write_setup_ophdr(ptr, ticket);

This line uses whitespaces for indentation, we should probably fix that
up somewhere in the series.

It goes away entirely so, yes, it is fixed up :)

quoted

 static inline void *
 xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
 		uint type)
 {
-	struct xfs_log_iovec *vec = *vecp;
+	struct xfs_log_iovec	*vec = *vecp;
+	struct xlog_op_header	*oph;
+	uint32_t		len;
+	void			*buf;
 
 	if (vec) {
 		ASSERT(vec - lv->lv_iovecp < lv->lv_niovecs);

@@ -44,21 +54,36 @@ xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
 		vec = &lv->lv_iovecp[0];
 	}
 
-	if (!IS_ALIGNED(lv->lv_buf_len, sizeof(uint64_t)))
-		lv->lv_buf_len = round_up(lv->lv_buf_len, sizeof(uint64_t));
+	len = lv->lv_buf_len + sizeof(struct xlog_op_header);
+	if (!IS_ALIGNED(len, sizeof(uint64_t))) {
+		lv->lv_buf_len = round_up(len, sizeof(uint64_t)) -
+					sizeof(struct xlog_op_header);
+	}
 
 	vec->i_type = type;
 	vec->i_addr = lv->lv_buf + lv->lv_buf_len;
 
-	ASSERT(IS_ALIGNED((unsigned long)vec->i_addr, sizeof(uint64_t)));
+	oph = vec->i_addr;
+	oph->oh_clientid = XFS_TRANSACTION;
+	oph->oh_res2 = 0;
+	oph->oh_flags = 0;
+
+	buf = vec->i_addr + sizeof(struct xlog_op_header);
+	ASSERT(IS_ALIGNED((unsigned long)buf, sizeof(uint64_t)));
 
 	*vecp = vec;
-	return vec->i_addr;
+	return buf;
 }

I think this function is growing a little too larger to stay inlined.

Possibly. let me have a look at code size and if it does make a
difference I'll move it out of line in another patch.

quoted

-		nbytes += niovecs * sizeof(uint64_t);
+		nbytes += niovecs * (sizeof(uint64_t) +
+					sizeof(struct xlog_op_header));;

Is it just me, or would

		nbytes += niovecs *
			(sizeof(uint64_t) + sizeof(struct xlog_op_header));

be a little easier to read?

Yes, that's better.

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com