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-rw-r--r--include/linux/blk-mq.h182
1 files changed, 182 insertions, 0 deletions
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
new file mode 100644
index 000000000000..746042ff321a
--- /dev/null
+++ b/include/linux/blk-mq.h
@@ -0,0 +1,182 @@
+#ifndef BLK_MQ_H
+#define BLK_MQ_H
+
+#include <linux/blkdev.h>
+
+struct blk_mq_tags;
+
+struct blk_mq_cpu_notifier {
+ struct list_head list;
+ void *data;
+ void (*notify)(void *data, unsigned long action, unsigned int cpu);
+};
+
+struct blk_mq_hw_ctx {
+ struct {
+ spinlock_t lock;
+ struct list_head dispatch;
+ } ____cacheline_aligned_in_smp;
+
+ unsigned long state; /* BLK_MQ_S_* flags */
+ struct delayed_work delayed_work;
+
+ unsigned long flags; /* BLK_MQ_F_* flags */
+
+ struct request_queue *queue;
+ unsigned int queue_num;
+
+ void *driver_data;
+
+ unsigned int nr_ctx;
+ struct blk_mq_ctx **ctxs;
+ unsigned int nr_ctx_map;
+ unsigned long *ctx_map;
+
+ struct request **rqs;
+ struct list_head page_list;
+ struct blk_mq_tags *tags;
+
+ unsigned long queued;
+ unsigned long run;
+#define BLK_MQ_MAX_DISPATCH_ORDER 10
+ unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER];
+
+ unsigned int queue_depth;
+ unsigned int numa_node;
+ unsigned int cmd_size; /* per-request extra data */
+
+ struct blk_mq_cpu_notifier cpu_notifier;
+ struct kobject kobj;
+};
+
+struct blk_mq_reg {
+ struct blk_mq_ops *ops;
+ unsigned int nr_hw_queues;
+ unsigned int queue_depth;
+ unsigned int reserved_tags;
+ unsigned int cmd_size; /* per-request extra data */
+ int numa_node;
+ unsigned int timeout;
+ unsigned int flags; /* BLK_MQ_F_* */
+};
+
+typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, struct request *);
+typedef struct blk_mq_hw_ctx *(map_queue_fn)(struct request_queue *, const int);
+typedef struct blk_mq_hw_ctx *(alloc_hctx_fn)(struct blk_mq_reg *,unsigned int);
+typedef void (free_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
+typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
+typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
+
+struct blk_mq_ops {
+ /*
+ * Queue request
+ */
+ queue_rq_fn *queue_rq;
+
+ /*
+ * Map to specific hardware queue
+ */
+ map_queue_fn *map_queue;
+
+ /*
+ * Called on request timeout
+ */
+ rq_timed_out_fn *timeout;
+
+ /*
+ * Override for hctx allocations (should probably go)
+ */
+ alloc_hctx_fn *alloc_hctx;
+ free_hctx_fn *free_hctx;
+
+ /*
+ * Called when the block layer side of a hardware queue has been
+ * set up, allowing the driver to allocate/init matching structures.
+ * Ditto for exit/teardown.
+ */
+ init_hctx_fn *init_hctx;
+ exit_hctx_fn *exit_hctx;
+};
+
+enum {
+ BLK_MQ_RQ_QUEUE_OK = 0, /* queued fine */
+ BLK_MQ_RQ_QUEUE_BUSY = 1, /* requeue IO for later */
+ BLK_MQ_RQ_QUEUE_ERROR = 2, /* end IO with error */
+
+ BLK_MQ_F_SHOULD_MERGE = 1 << 0,
+ BLK_MQ_F_SHOULD_SORT = 1 << 1,
+ BLK_MQ_F_SHOULD_IPI = 1 << 2,
+
+ BLK_MQ_S_STOPPED = 1 << 0,
+
+ BLK_MQ_MAX_DEPTH = 2048,
+};
+
+struct request_queue *blk_mq_init_queue(struct blk_mq_reg *, void *);
+void blk_mq_free_queue(struct request_queue *);
+int blk_mq_register_disk(struct gendisk *);
+void blk_mq_unregister_disk(struct gendisk *);
+void blk_mq_init_commands(struct request_queue *, void (*init)(void *data, struct blk_mq_hw_ctx *, struct request *, unsigned int), void *data);
+
+void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
+
+void blk_mq_insert_request(struct request_queue *, struct request *, bool);
+void blk_mq_run_queues(struct request_queue *q, bool async);
+void blk_mq_free_request(struct request *rq);
+bool blk_mq_can_queue(struct blk_mq_hw_ctx *);
+struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp);
+struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw, gfp_t gfp);
+struct request *blk_mq_rq_from_tag(struct request_queue *q, unsigned int tag);
+
+struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index);
+struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_reg *, unsigned int);
+void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *, unsigned int);
+
+void blk_mq_end_io(struct request *rq, int error);
+
+void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
+void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx);
+void blk_mq_start_stopped_hw_queues(struct request_queue *q);
+
+/*
+ * Driver command data is immediately after the request. So subtract request
+ * size to get back to the original request.
+ */
+static inline struct request *blk_mq_rq_from_pdu(void *pdu)
+{
+ return pdu - sizeof(struct request);
+}
+static inline void *blk_mq_rq_to_pdu(struct request *rq)
+{
+ return (void *) rq + sizeof(*rq);
+}
+
+static inline struct request *blk_mq_tag_to_rq(struct blk_mq_hw_ctx *hctx,
+ unsigned int tag)
+{
+ return hctx->rqs[tag];
+}
+
+#define queue_for_each_hw_ctx(q, hctx, i) \
+ for ((i) = 0, hctx = (q)->queue_hw_ctx[0]; \
+ (i) < (q)->nr_hw_queues; (i)++, hctx = (q)->queue_hw_ctx[i])
+
+#define queue_for_each_ctx(q, ctx, i) \
+ for ((i) = 0, ctx = per_cpu_ptr((q)->queue_ctx, 0); \
+ (i) < (q)->nr_queues; (i)++, ctx = per_cpu_ptr(q->queue_ctx, (i)))
+
+#define hctx_for_each_ctx(hctx, ctx, i) \
+ for ((i) = 0, ctx = (hctx)->ctxs[0]; \
+ (i) < (hctx)->nr_ctx; (i)++, ctx = (hctx)->ctxs[(i)])
+
+#define blk_ctx_sum(q, sum) \
+({ \
+ struct blk_mq_ctx *__x; \
+ unsigned int __ret = 0, __i; \
+ \
+ queue_for_each_ctx((q), __x, __i) \
+ __ret += sum; \
+ __ret; \
+})
+
+#endif