1 files changed, 57 insertions, 18 deletions

diff --git a/block/blk.h b/block/blk.h
index e180863f918b..c718e4291db0 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -331,33 +331,67 @@ ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
 ssize_t part_timeout_store(struct device *, struct device_attribute *,
 				const char *, size_t);
 
-static inline bool bio_may_exceed_limits(struct bio *bio,
-					 const struct queue_limits *lim)
+struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nsegs);
+struct bio *bio_split_write_zeroes(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nsegs);
+struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
+		unsigned *nr_segs);
+struct bio *bio_split_zone_append(struct bio *bio,
+		const struct queue_limits *lim, unsigned *nr_segs);
+
+/*
+ * All drivers must accept single-segments bios that are smaller than PAGE_SIZE.
+ *
+ * This is a quick and dirty check that relies on the fact that bi_io_vec[0] is
+ * always valid if a bio has data.  The check might lead to occasional false
+ * positives when bios are cloned, but compared to the performance impact of
+ * cloned bios themselves the loop below doesn't matter anyway.
+ */
+static inline bool bio_may_need_split(struct bio *bio,
+		const struct queue_limits *lim)
+{
+	return lim->chunk_sectors || bio->bi_vcnt != 1 ||
+		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
+}
+
+/**
+ * __bio_split_to_limits - split a bio to fit the queue limits
+ * @bio:     bio to be split
+ * @lim:     queue limits to split based on
+ * @nr_segs: returns the number of segments in the returned bio
+ *
+ * Check if @bio needs splitting based on the queue limits, and if so split off
+ * a bio fitting the limits from the beginning of @bio and return it.  @bio is
+ * shortened to the remainder and re-submitted.
+ *
+ * The split bio is allocated from @q->bio_split, which is provided by the
+ * block layer.
+ */
+static inline struct bio *__bio_split_to_limits(struct bio *bio,
+		const struct queue_limits *lim, unsigned int *nr_segs)
 {
 	switch (bio_op(bio)) {
+	case REQ_OP_READ:
+	case REQ_OP_WRITE:
+		if (bio_may_need_split(bio, lim))
+			return bio_split_rw(bio, lim, nr_segs);
+		*nr_segs = 1;
+		return bio;
+	case REQ_OP_ZONE_APPEND:
+		return bio_split_zone_append(bio, lim, nr_segs);
 	case REQ_OP_DISCARD:
 	case REQ_OP_SECURE_ERASE:
+		return bio_split_discard(bio, lim, nr_segs);
 	case REQ_OP_WRITE_ZEROES:
-		return true; /* non-trivial splitting decisions */
+		return bio_split_write_zeroes(bio, lim, nr_segs);
 	default:
-		break;
+		/* other operations can't be split */
+		*nr_segs = 0;
+		return bio;
 	}
-
-	/*
-	 * All drivers must accept single-segments bios that are <= PAGE_SIZE.
-	 * This is a quick and dirty check that relies on the fact that
-	 * bi_io_vec[0] is always valid if a bio has data.  The check might
-	 * lead to occasional false negatives when bios are cloned, but compared
-	 * to the performance impact of cloned bios themselves the loop below
-	 * doesn't matter anyway.
-	 */
-	return lim->chunk_sectors || bio->bi_vcnt != 1 ||
-		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
 }
 
-struct bio *__bio_split_to_limits(struct bio *bio,
-				  const struct queue_limits *lim,
-				  unsigned int *nr_segs);
 int ll_back_merge_fn(struct request *req, struct bio *bio,
 		unsigned int nr_segs);
 bool blk_attempt_req_merge(struct request_queue *q, struct request *rq,
@@ -540,6 +574,10 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 		struct page *page, unsigned int len, unsigned int offset,
 		unsigned int max_sectors, bool *same_page);
 
+int bio_add_hw_folio(struct request_queue *q, struct bio *bio,
+		struct folio *folio, size_t len, size_t offset,
+		unsigned int max_sectors, bool *same_page);
+
 /*
  * Clean up a page appropriately, where the page may be pinned, may have a
  * ref taken on it or neither.
@@ -571,6 +609,7 @@ blk_mode_t file_to_blk_mode(struct file *file);
 int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 		loff_t lstart, loff_t lend);
 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
+int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags);
 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
 
 extern const struct address_space_operations def_blk_aops;