1 #ifndef BLK_INTERNAL_H 2 #define BLK_INTERNAL_H 3 4 /* Amount of time in which a process may batch requests */ 5 #define BLK_BATCH_TIME (HZ/50UL) 6 7 /* Number of requests a "batching" process may submit */ 8 #define BLK_BATCH_REQ 32 9 10 extern struct kmem_cache *blk_requestq_cachep; 11 extern struct kobj_type blk_queue_ktype; 12 13 void init_request_from_bio(struct request *req, struct bio *bio); 14 void blk_rq_bio_prep(struct request_queue *q, struct request *rq, 15 struct bio *bio); 16 void __blk_queue_free_tags(struct request_queue *q); 17 18 void blk_unplug_work(struct work_struct *work); 19 void blk_unplug_timeout(unsigned long data); 20 void blk_rq_timed_out_timer(unsigned long data); 21 void blk_delete_timer(struct request *); 22 void blk_add_timer(struct request *); 23 void __generic_unplug_device(struct request_queue *); 24 25 /* 26 * Internal atomic flags for request handling 27 */ 28 enum rq_atomic_flags { 29 REQ_ATOM_COMPLETE = 0, 30 }; 31 32 /* 33 * EH timer and IO completion will both attempt to 'grab' the request, make 34 * sure that only one of them suceeds 35 */ 36 static inline int blk_mark_rq_complete(struct request *rq) 37 { 38 return test_and_set_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); 39 } 40 41 static inline void blk_clear_rq_complete(struct request *rq) 42 { 43 clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); 44 } 45 46 #ifdef CONFIG_FAIL_IO_TIMEOUT 47 int blk_should_fake_timeout(struct request_queue *); 48 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *); 49 ssize_t part_timeout_store(struct device *, struct device_attribute *, 50 const char *, size_t); 51 #else 52 static inline int blk_should_fake_timeout(struct request_queue *q) 53 { 54 return 0; 55 } 56 #endif 57 58 struct io_context *current_io_context(gfp_t gfp_flags, int node); 59 60 int ll_back_merge_fn(struct request_queue *q, struct request *req, 61 struct bio *bio); 62 int ll_front_merge_fn(struct request_queue *q, struct request *req, 63 struct bio *bio); 64 int attempt_back_merge(struct request_queue *q, struct request *rq); 65 int attempt_front_merge(struct request_queue *q, struct request *rq); 66 void blk_recalc_rq_segments(struct request *rq); 67 void blk_recalc_rq_sectors(struct request *rq, int nsect); 68 69 void blk_queue_congestion_threshold(struct request_queue *q); 70 71 int blk_dev_init(void); 72 73 void elv_quiesce_start(struct request_queue *q); 74 void elv_quiesce_end(struct request_queue *q); 75 76 77 /* 78 * Return the threshold (number of used requests) at which the queue is 79 * considered to be congested. It include a little hysteresis to keep the 80 * context switch rate down. 81 */ 82 static inline int queue_congestion_on_threshold(struct request_queue *q) 83 { 84 return q->nr_congestion_on; 85 } 86 87 /* 88 * The threshold at which a queue is considered to be uncongested 89 */ 90 static inline int queue_congestion_off_threshold(struct request_queue *q) 91 { 92 return q->nr_congestion_off; 93 } 94 95 #if defined(CONFIG_BLK_DEV_INTEGRITY) 96 97 #define rq_for_each_integrity_segment(bvl, _rq, _iter) \ 98 __rq_for_each_bio(_iter.bio, _rq) \ 99 bip_for_each_vec(bvl, _iter.bio->bi_integrity, _iter.i) 100 101 #endif /* BLK_DEV_INTEGRITY */ 102 103 static inline int blk_cpu_to_group(int cpu) 104 { 105 #ifdef CONFIG_SCHED_MC 106 const struct cpumask *mask = cpu_coregroup_mask(cpu); 107 return cpumask_first(mask); 108 #elif defined(CONFIG_SCHED_SMT) 109 return cpumask_first(topology_thread_cpumask(cpu)); 110 #else 111 return cpu; 112 #endif 113 } 114 115 static inline int blk_do_io_stat(struct request *rq) 116 { 117 return rq->rq_disk && blk_rq_io_stat(rq); 118 } 119 120 #endif 121