dm: rename 'bio' member of dm_io structure to 'orig_bio'

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm.c

@@ -60,13 +60,13 @@ void dm_issue_global_event(void)
 }
 
 /*
- * One of these is allocated per bio.
+ * One of these is allocated per original bio.
  */
 struct dm_io {
 	struct mapped_device *md;
 	blk_status_t status;
 	atomic_t io_count;
-	struct bio *bio;
+	struct bio *orig_bio;
 	unsigned long start_time;
 	spinlock_t endio_lock;
 	struct dm_stats_aux stats_aux;
@@ -510,7 +510,7 @@ int md_in_flight(struct mapped_device *md)
 static void start_io_acct(struct dm_io *io)
 {
 	struct mapped_device *md = io->md;
-	struct bio *bio = io->bio;
+	struct bio *bio = io->orig_bio;
 	int cpu;
 	int rw = bio_data_dir(bio);
 
@@ -531,7 +531,7 @@ static void start_io_acct(struct dm_io *io)
 static void end_io_acct(struct dm_io *io)
 {
 	struct mapped_device *md = io->md;
-	struct bio *bio = io->bio;
+	struct bio *bio = io->orig_bio;
 	unsigned long duration = jiffies - io->start_time;
 	int pending;
 	int rw = bio_data_dir(bio);
@@ -771,8 +771,7 @@ static void dec_pending(struct dm_io *io, blk_status_t error)
 	/* Push-back supersedes any I/O errors */
 	if (unlikely(error)) {
 		spin_lock_irqsave(&io->endio_lock, flags);
-		if (!(io->status == BLK_STS_DM_REQUEUE &&
-				__noflush_suspending(md)))
+		if (!(io->status == BLK_STS_DM_REQUEUE && __noflush_suspending(md)))
 			io->status = error;
 		spin_unlock_irqrestore(&io->endio_lock, flags);
 	}
@@ -784,7 +783,8 @@ static void dec_pending(struct dm_io *io, blk_status_t error)
 			 */
 			spin_lock_irqsave(&md->deferred_lock, flags);
 			if (__noflush_suspending(md))
-				bio_list_add_head(&md->deferred, io->bio);
+				/* NOTE early return due to BLK_STS_DM_REQUEUE below */
+				bio_list_add_head(&md->deferred, io->orig_bio);
 			else
 				/* noflush suspend was interrupted. */
 				io->status = BLK_STS_IOERR;
@@ -792,7 +792,7 @@ static void dec_pending(struct dm_io *io, blk_status_t error)
 		}
 
 		io_error = io->status;
-		bio = io->bio;
+		bio = io->orig_bio;
 		end_io_acct(io);
 		free_io(md, io);
 
@@ -1038,7 +1038,7 @@ void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, sector_t start)
 {
 #ifdef CONFIG_BLK_DEV_ZONED
 	struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
-	struct bio *report_bio = tio->io->bio;
+	struct bio *report_bio = tio->io->orig_bio;
 	struct blk_zone_report_hdr *hdr = NULL;
 	struct blk_zone *zone;
 	unsigned int nr_rep = 0;
@@ -1129,7 +1129,7 @@ static void __map_bio(struct dm_target_io *tio)
 	case DM_MAPIO_REMAPPED:
 		/* the bio has been remapped so dispatch it */
 		trace_block_bio_remap(clone->bi_disk->queue, clone,
-				      bio_dev(tio->io->bio), sector);
+				      bio_dev(tio->io->orig_bio), sector);
 		generic_make_request(clone);
 		break;
 	case DM_MAPIO_KILL:
@@ -1441,7 +1441,7 @@ static void __split_and_process_bio(struct mapped_device *md,
 	ci.io = alloc_io(md);
 	ci.io->status = 0;
 	atomic_set(&ci.io->io_count, 1);
-	ci.io->bio = bio;
+	ci.io->orig_bio = bio;
 	ci.io->md = md;
 	spin_lock_init(&ci.io->endio_lock);
 	ci.sector = bio->bi_iter.bi_sector;
@@ -1468,15 +1468,15 @@ static void __split_and_process_bio(struct mapped_device *md,
 				 * so that it gets handled *after* bios already submitted
 				 * have been completely processed.
 				 * We take a clone of the original to store in
-				 * ci.io->bio to be used by end_io_acct() and
+				 * ci.io->orig_bio to be used by end_io_acct() and
 				 * for dec_pending to use for completion handling.
 				 * As this path is not used for REQ_OP_ZONE_REPORT,
-				 * the usage of io->bio in dm_remap_zone_report()
+				 * the usage of io->orig_bio in dm_remap_zone_report()
 				 * won't be affected by this reassignment.
 				 */
 				struct bio *b = bio_clone_bioset(bio, GFP_NOIO,
 								 md->queue->bio_split);
-				ci.io->bio = b;
+				ci.io->orig_bio = b;
 				bio_advance(bio, (bio_sectors(bio) - ci.sector_count) << 9);
 				bio_chain(b, bio);
 				generic_make_request(bio);