block: lift bio_is_zone_append to bio.h

Make bio_is_zone_append globally available, because file systems need
to use to check for a zone append bio in their end_io handlers to deal
with the block layer emulation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20241104062647.91160-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: Christoph Hellwig

block/blk.h

@@ -457,11 +457,6 @@ static inline bool bio_zone_write_plugging(struct bio *bio)
 {
 	return bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING);
 }
-static inline bool bio_is_zone_append(struct bio *bio)
-{
-	return bio_op(bio) == REQ_OP_ZONE_APPEND ||
-		bio_flagged(bio, BIO_EMULATES_ZONE_APPEND);
-}
 void blk_zone_write_plug_bio_merged(struct bio *bio);
 void blk_zone_write_plug_init_request(struct request *rq);
 static inline void blk_zone_update_request_bio(struct request *rq,
@@ -510,10 +505,6 @@ static inline bool bio_zone_write_plugging(struct bio *bio)
 {
 	return false;
 }
-static inline bool bio_is_zone_append(struct bio *bio)
-{
-	return false;
-}
 static inline void blk_zone_write_plug_bio_merged(struct bio *bio)
 {
 }

include/linux/bio.h

@@ -675,6 +675,23 @@ static inline void bio_clear_polled(struct bio *bio)
 	bio->bi_opf &= ~REQ_POLLED;
 }
 
+/**
+ * bio_is_zone_append - is this a zone append bio?
+ * @bio:	bio to check
+ *
+ * Check if @bio is a zone append operation.  Core block layer code and end_io
+ * handlers must use this instead of an open coded REQ_OP_ZONE_APPEND check
+ * because the block layer can rewrite REQ_OP_ZONE_APPEND to REQ_OP_WRITE if
+ * it is not natively supported.
+ */
+static inline bool bio_is_zone_append(struct bio *bio)
+{
+	if (!IS_ENABLED(CONFIG_BLK_DEV_ZONED))
+		return false;
+	return bio_op(bio) == REQ_OP_ZONE_APPEND ||
+		bio_flagged(bio, BIO_EMULATES_ZONE_APPEND);
+}
+
 struct bio *blk_next_bio(struct bio *bio, struct block_device *bdev,
 		unsigned int nr_pages, blk_opf_t opf, gfp_t gfp);
 struct bio *bio_chain_and_submit(struct bio *prev, struct bio *new);