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-rw-r--r--block/blk.h53
1 files changed, 53 insertions, 0 deletions
diff --git a/block/blk.h b/block/blk.h
new file mode 100644
index 00000000000..ec898dd0c65
--- /dev/null
+++ b/block/blk.h
@@ -0,0 +1,53 @@
+#ifndef BLK_INTERNAL_H
+#define BLK_INTERNAL_H
+
+/* Amount of time in which a process may batch requests */
+#define BLK_BATCH_TIME (HZ/50UL)
+
+/* Number of requests a "batching" process may submit */
+#define BLK_BATCH_REQ 32
+
+extern struct kmem_cache *blk_requestq_cachep;
+extern struct kobj_type blk_queue_ktype;
+
+void rq_init(struct request_queue *q, struct request *rq);
+void init_request_from_bio(struct request *req, struct bio *bio);
+void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
+ struct bio *bio);
+void __blk_queue_free_tags(struct request_queue *q);
+
+void blk_unplug_work(struct work_struct *work);
+void blk_unplug_timeout(unsigned long data);
+
+struct io_context *current_io_context(gfp_t gfp_flags, int node);
+
+int ll_back_merge_fn(struct request_queue *q, struct request *req,
+ struct bio *bio);
+int ll_front_merge_fn(struct request_queue *q, struct request *req,
+ struct bio *bio);
+int attempt_back_merge(struct request_queue *q, struct request *rq);
+int attempt_front_merge(struct request_queue *q, struct request *rq);
+void blk_recalc_rq_segments(struct request *rq);
+void blk_recalc_rq_sectors(struct request *rq, int nsect);
+
+void blk_queue_congestion_threshold(struct request_queue *q);
+
+/*
+ * Return the threshold (number of used requests) at which the queue is
+ * considered to be congested. It include a little hysteresis to keep the
+ * context switch rate down.
+ */
+static inline int queue_congestion_on_threshold(struct request_queue *q)
+{
+ return q->nr_congestion_on;
+}
+
+/*
+ * The threshold at which a queue is considered to be uncongested
+ */
+static inline int queue_congestion_off_threshold(struct request_queue *q)
+{
+ return q->nr_congestion_off;
+}
+
+#endif