Initial import

1 files changed, 126 insertions, 0 deletions

diff --git a/block/blk-mq.h b/block/blk-mq.h
new file mode 100644
index 000000000..6a48c4c0d
--- /dev/null
+++ b/block/blk-mq.h
@@ -0,0 +1,126 @@
+#ifndef INT_BLK_MQ_H
+#define INT_BLK_MQ_H
+
+struct blk_mq_tag_set;
+
+struct blk_mq_ctx {
+	struct {
+		spinlock_t		lock;
+		struct list_head	rq_list;
+	}  ____cacheline_aligned_in_smp;
+
+	unsigned int		cpu;
+	unsigned int		index_hw;
+
+	unsigned int		last_tag ____cacheline_aligned_in_smp;
+
+	/* incremented at dispatch time */
+	unsigned long		rq_dispatched[2];
+	unsigned long		rq_merged;
+
+	/* incremented at completion time */
+	unsigned long		____cacheline_aligned_in_smp rq_completed[2];
+
+	struct request_queue	*queue;
+	struct kobject		kobj;
+} ____cacheline_aligned_in_smp;
+
+void __blk_mq_complete_request(struct request *rq);
+void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
+void blk_mq_freeze_queue(struct request_queue *q);
+void blk_mq_free_queue(struct request_queue *q);
+void blk_mq_clone_flush_request(struct request *flush_rq,
+		struct request *orig_rq);
+int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
+void blk_mq_wake_waiters(struct request_queue *q);
+
+/*
+ * CPU hotplug helpers
+ */
+struct blk_mq_cpu_notifier;
+void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier,
+			      int (*fn)(void *, unsigned long, unsigned int),
+			      void *data);
+void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier);
+void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier);
+void blk_mq_cpu_init(void);
+void blk_mq_enable_hotplug(void);
+void blk_mq_disable_hotplug(void);
+
+/*
+ * CPU -> queue mappings
+ */
+extern unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set);
+extern int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues);
+extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
+
+/*
+ * sysfs helpers
+ */
+extern int blk_mq_sysfs_register(struct request_queue *q);
+extern void blk_mq_sysfs_unregister(struct request_queue *q);
+
+extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
+
+void blk_mq_release(struct request_queue *q);
+
+/*
+ * Basic implementation of sparser bitmap, allowing the user to spread
+ * the bits over more cachelines.
+ */
+struct blk_align_bitmap {
+	unsigned long word;
+	unsigned long depth;
+} ____cacheline_aligned_in_smp;
+
+static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
+					   unsigned int cpu)
+{
+	return per_cpu_ptr(q->queue_ctx, cpu);
+}
+
+/*
+ * This assumes per-cpu software queueing queues. They could be per-node
+ * as well, for instance. For now this is hardcoded as-is. Note that we don't
+ * care about preemption, since we know the ctx's are persistent. This does
+ * mean that we can't rely on ctx always matching the currently running CPU.
+ */
+static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
+{
+	return __blk_mq_get_ctx(q, get_cpu());
+}
+
+static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
+{
+	put_cpu();
+}
+
+struct blk_mq_alloc_data {
+	/* input parameter */
+	struct request_queue *q;
+	gfp_t gfp;
+	bool reserved;
+
+	/* input & output parameter */
+	struct blk_mq_ctx *ctx;
+	struct blk_mq_hw_ctx *hctx;
+};
+
+static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data,
+		struct request_queue *q, gfp_t gfp, bool reserved,
+		struct blk_mq_ctx *ctx,
+		struct blk_mq_hw_ctx *hctx)
+{
+	data->q = q;
+	data->gfp = gfp;
+	data->reserved = reserved;
+	data->ctx = ctx;
+	data->hctx = hctx;
+}
+
+static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
+{
+	return hctx->nr_ctx && hctx->tags;
+}
+
+#endif