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#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;
int (*notify)(void *data, unsigned long action, unsigned int cpu);
};
struct blk_mq_ctxmap {
unsigned int map_size;
unsigned int bits_per_word;
struct blk_align_bitmap *map;
};
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 run_work;
struct delayed_work delay_work;
cpumask_var_t cpumask;
int next_cpu;
int next_cpu_batch;
unsigned long flags; /* BLK_MQ_F_* flags */
struct request_queue *queue;
unsigned int queue_num;
void *driver_data;
struct blk_mq_ctxmap ctx_map;
unsigned int nr_ctx;
struct blk_mq_ctx **ctxs;
unsigned int wait_index;
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 numa_node;
unsigned int cmd_size; /* per-request extra data */
atomic_t nr_active;
struct blk_mq_cpu_notifier cpu_notifier;
struct kobject kobj;
};
struct blk_mq_tag_set {
struct blk_mq_ops *ops;
unsigned int nr_hw_queues;
unsigned int queue_depth; /* max hw supported */
unsigned int reserved_tags;
unsigned int cmd_size; /* per-request extra data */
int numa_node;
unsigned int timeout;
unsigned int flags; /* BLK_MQ_F_* */
void *driver_data;
struct blk_mq_tags **tags;
struct mutex tag_list_lock;
struct list_head tag_list;
};
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 int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
typedef int (init_request_fn)(void *, struct request *, unsigned int,
unsigned int, unsigned int);
typedef void (exit_request_fn)(void *, struct request *, unsigned int,
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;
softirq_done_fn *complete;
/*
* 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;
/*
* Called for every command allocated by the block layer to allow
* the driver to set up driver specific data.
* Ditto for exit/teardown.
*/
init_request_fn *init_request;
exit_request_fn *exit_request;
};
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_TAG_SHARED = 1 << 2,
BLK_MQ_F_SG_MERGE = 1 << 3,
BLK_MQ_S_STOPPED = 0,
BLK_MQ_S_TAG_ACTIVE = 1,
BLK_MQ_MAX_DEPTH = 2048,
BLK_MQ_CPU_WORK_BATCH = 8,
};
struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
int blk_mq_register_disk(struct gendisk *);
void blk_mq_unregister_disk(struct gendisk *);
int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set);
void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
void blk_mq_insert_request(struct request *, bool, bool, 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, bool reserved);
struct request *blk_mq_tag_to_rq(struct blk_mq_hw_ctx *hctx, 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_tag_set *, unsigned int, int);
void blk_mq_end_io(struct request *rq, int error);
void __blk_mq_end_io(struct request *rq, int error);
void blk_mq_requeue_request(struct request *rq);
void blk_mq_add_to_requeue_list(struct request *rq, bool at_head);
void blk_mq_kick_requeue_list(struct request_queue *q);
void blk_mq_complete_request(struct request *rq);
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_stop_hw_queues(struct request_queue *q);
void blk_mq_start_hw_queues(struct request_queue *q);
void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
void blk_mq_tag_busy_iter(struct blk_mq_tags *tags, void (*fn)(void *data, unsigned long *), void *data);
/*
* 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);
}
#define queue_for_each_hw_ctx(q, hctx, i) \
for ((i) = 0; (i) < (q)->nr_hw_queues && \
({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++)
#define queue_for_each_ctx(q, ctx, i) \
for ((i) = 0; (i) < (q)->nr_queues && \
({ ctx = per_cpu_ptr((q)->queue_ctx, (i)); 1; }); (i)++)
#define hctx_for_each_ctx(hctx, ctx, i) \
for ((i) = 0; (i) < (hctx)->nr_ctx && \
({ ctx = (hctx)->ctxs[(i)]; 1; }); (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
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