1 /* SPDX-License-Identifier: GPL-2.0 */
6 #include <linux/blk-mq.h>
9 /* Amount of time in which a process may batch requests */
10 #define BLK_BATCH_TIME (HZ/50UL)
12 /* Number of requests a "batching" process may submit */
13 #define BLK_BATCH_REQ 32
15 /* Max future timer expiry for timeouts */
16 #define BLK_MAX_TIMEOUT (5 * HZ)
18 #ifdef CONFIG_DEBUG_FS
19 extern struct dentry
*blk_debugfs_root
;
22 struct blk_flush_queue
{
23 unsigned int flush_queue_delayed
:1;
24 unsigned int flush_pending_idx
:1;
25 unsigned int flush_running_idx
:1;
26 unsigned long flush_pending_since
;
27 struct list_head flush_queue
[2];
28 struct list_head flush_data_in_flight
;
29 struct request
*flush_rq
;
32 * flush_rq shares tag with this rq, both can't be active
35 struct request
*orig_rq
;
36 spinlock_t mq_flush_lock
;
39 extern struct kmem_cache
*blk_requestq_cachep
;
40 extern struct kmem_cache
*request_cachep
;
41 extern struct kobj_type blk_queue_ktype
;
42 extern struct ida blk_queue_ida
;
44 static inline struct blk_flush_queue
*blk_get_flush_queue(
45 struct request_queue
*q
, struct blk_mq_ctx
*ctx
)
48 return blk_mq_map_queue(q
, ctx
->cpu
)->fq
;
52 static inline void __blk_get_queue(struct request_queue
*q
)
54 kobject_get(&q
->kobj
);
57 struct blk_flush_queue
*blk_alloc_flush_queue(struct request_queue
*q
,
58 int node
, int cmd_size
);
59 void blk_free_flush_queue(struct blk_flush_queue
*q
);
61 int blk_init_rl(struct request_list
*rl
, struct request_queue
*q
,
63 void blk_exit_rl(struct request_queue
*q
, struct request_list
*rl
);
64 void blk_rq_bio_prep(struct request_queue
*q
, struct request
*rq
,
66 void blk_queue_bypass_start(struct request_queue
*q
);
67 void blk_queue_bypass_end(struct request_queue
*q
);
68 void __blk_queue_free_tags(struct request_queue
*q
);
69 void blk_freeze_queue(struct request_queue
*q
);
71 static inline void blk_queue_enter_live(struct request_queue
*q
)
74 * Given that running in generic_make_request() context
75 * guarantees that a live reference against q_usage_counter has
76 * been established, further references under that same context
77 * need not check that the queue has been frozen (marked dead).
79 percpu_ref_get(&q
->q_usage_counter
);
82 #ifdef CONFIG_BLK_DEV_INTEGRITY
83 void blk_flush_integrity(void);
84 bool __bio_integrity_endio(struct bio
*);
85 static inline bool bio_integrity_endio(struct bio
*bio
)
87 if (bio_integrity(bio
))
88 return __bio_integrity_endio(bio
);
92 static inline void blk_flush_integrity(void)
95 static inline bool bio_integrity_endio(struct bio
*bio
)
101 void blk_timeout_work(struct work_struct
*work
);
102 unsigned long blk_rq_timeout(unsigned long timeout
);
103 void blk_add_timer(struct request
*req
);
104 void blk_delete_timer(struct request
*);
107 bool bio_attempt_front_merge(struct request_queue
*q
, struct request
*req
,
109 bool bio_attempt_back_merge(struct request_queue
*q
, struct request
*req
,
111 bool bio_attempt_discard_merge(struct request_queue
*q
, struct request
*req
,
113 bool blk_attempt_plug_merge(struct request_queue
*q
, struct bio
*bio
,
114 unsigned int *request_count
,
115 struct request
**same_queue_rq
);
116 unsigned int blk_plug_queued_count(struct request_queue
*q
);
118 void blk_account_io_start(struct request
*req
, bool new_io
);
119 void blk_account_io_completion(struct request
*req
, unsigned int bytes
);
120 void blk_account_io_done(struct request
*req
);
123 * EH timer and IO completion will both attempt to 'grab' the request, make
124 * sure that only one of them succeeds. Steal the bottom bit of the
125 * __deadline field for this.
127 static inline int blk_mark_rq_complete(struct request
*rq
)
129 return test_and_set_bit(0, &rq
->__deadline
);
132 static inline void blk_clear_rq_complete(struct request
*rq
)
134 clear_bit(0, &rq
->__deadline
);
137 static inline bool blk_rq_is_complete(struct request
*rq
)
139 return test_bit(0, &rq
->__deadline
);
143 * Internal elevator interface
145 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
147 void blk_insert_flush(struct request
*rq
);
149 static inline void elv_activate_rq(struct request_queue
*q
, struct request
*rq
)
151 struct elevator_queue
*e
= q
->elevator
;
153 if (e
->type
->ops
.sq
.elevator_activate_req_fn
)
154 e
->type
->ops
.sq
.elevator_activate_req_fn(q
, rq
);
157 static inline void elv_deactivate_rq(struct request_queue
*q
, struct request
*rq
)
159 struct elevator_queue
*e
= q
->elevator
;
161 if (e
->type
->ops
.sq
.elevator_deactivate_req_fn
)
162 e
->type
->ops
.sq
.elevator_deactivate_req_fn(q
, rq
);
165 struct hd_struct
*__disk_get_part(struct gendisk
*disk
, int partno
);
167 #ifdef CONFIG_FAIL_IO_TIMEOUT
168 int blk_should_fake_timeout(struct request_queue
*);
169 ssize_t
part_timeout_show(struct device
*, struct device_attribute
*, char *);
170 ssize_t
part_timeout_store(struct device
*, struct device_attribute
*,
171 const char *, size_t);
173 static inline int blk_should_fake_timeout(struct request_queue
*q
)
179 int ll_back_merge_fn(struct request_queue
*q
, struct request
*req
,
181 int ll_front_merge_fn(struct request_queue
*q
, struct request
*req
,
183 struct request
*attempt_back_merge(struct request_queue
*q
, struct request
*rq
);
184 struct request
*attempt_front_merge(struct request_queue
*q
, struct request
*rq
);
185 int blk_attempt_req_merge(struct request_queue
*q
, struct request
*rq
,
186 struct request
*next
);
187 void blk_recalc_rq_segments(struct request
*rq
);
188 void blk_rq_set_mixed_merge(struct request
*rq
);
189 bool blk_rq_merge_ok(struct request
*rq
, struct bio
*bio
);
190 enum elv_merge
blk_try_merge(struct request
*rq
, struct bio
*bio
);
192 void blk_queue_congestion_threshold(struct request_queue
*q
);
194 int blk_dev_init(void);
198 * Return the threshold (number of used requests) at which the queue is
199 * considered to be congested. It include a little hysteresis to keep the
200 * context switch rate down.
202 static inline int queue_congestion_on_threshold(struct request_queue
*q
)
204 return q
->nr_congestion_on
;
208 * The threshold at which a queue is considered to be uncongested
210 static inline int queue_congestion_off_threshold(struct request_queue
*q
)
212 return q
->nr_congestion_off
;
215 extern int blk_update_nr_requests(struct request_queue
*, unsigned int);
218 * Contribute to IO statistics IFF:
220 * a) it's attached to a gendisk, and
221 * b) the queue had IO stats enabled when this request was started, and
222 * c) it's a file system request
224 static inline int blk_do_io_stat(struct request
*rq
)
226 return rq
->rq_disk
&&
227 (rq
->rq_flags
& RQF_IO_STAT
) &&
228 !blk_rq_is_passthrough(rq
);
231 static inline void req_set_nomerge(struct request_queue
*q
, struct request
*req
)
233 req
->cmd_flags
|= REQ_NOMERGE
;
234 if (req
== q
->last_merge
)
235 q
->last_merge
= NULL
;
239 * Steal a bit from this field for legacy IO path atomic IO marking. Note that
240 * setting the deadline clears the bottom bit, potentially clearing the
241 * completed bit. The user has to be OK with this (current ones are fine).
243 static inline void blk_rq_set_deadline(struct request
*rq
, unsigned long time
)
245 rq
->__deadline
= time
& ~0x1UL
;
248 static inline unsigned long blk_rq_deadline(struct request
*rq
)
250 return rq
->__deadline
& ~0x1UL
;
254 * Internal io_context interface
256 void get_io_context(struct io_context
*ioc
);
257 struct io_cq
*ioc_lookup_icq(struct io_context
*ioc
, struct request_queue
*q
);
258 struct io_cq
*ioc_create_icq(struct io_context
*ioc
, struct request_queue
*q
,
260 void ioc_clear_queue(struct request_queue
*q
);
262 int create_task_io_context(struct task_struct
*task
, gfp_t gfp_mask
, int node
);
265 * rq_ioc - determine io_context for request allocation
266 * @bio: request being allocated is for this bio (can be %NULL)
268 * Determine io_context to use for request allocation for @bio. May return
269 * %NULL if %current->io_context doesn't exist.
271 static inline struct io_context
*rq_ioc(struct bio
*bio
)
273 #ifdef CONFIG_BLK_CGROUP
274 if (bio
&& bio
->bi_ioc
)
277 return current
->io_context
;
281 * create_io_context - try to create task->io_context
282 * @gfp_mask: allocation mask
283 * @node: allocation node
285 * If %current->io_context is %NULL, allocate a new io_context and install
286 * it. Returns the current %current->io_context which may be %NULL if
289 * Note that this function can't be called with IRQ disabled because
290 * task_lock which protects %current->io_context is IRQ-unsafe.
292 static inline struct io_context
*create_io_context(gfp_t gfp_mask
, int node
)
294 WARN_ON_ONCE(irqs_disabled());
295 if (unlikely(!current
->io_context
))
296 create_task_io_context(current
, gfp_mask
, node
);
297 return current
->io_context
;
301 * Internal throttling interface
303 #ifdef CONFIG_BLK_DEV_THROTTLING
304 extern void blk_throtl_drain(struct request_queue
*q
);
305 extern int blk_throtl_init(struct request_queue
*q
);
306 extern void blk_throtl_exit(struct request_queue
*q
);
307 extern void blk_throtl_register_queue(struct request_queue
*q
);
308 #else /* CONFIG_BLK_DEV_THROTTLING */
309 static inline void blk_throtl_drain(struct request_queue
*q
) { }
310 static inline int blk_throtl_init(struct request_queue
*q
) { return 0; }
311 static inline void blk_throtl_exit(struct request_queue
*q
) { }
312 static inline void blk_throtl_register_queue(struct request_queue
*q
) { }
313 #endif /* CONFIG_BLK_DEV_THROTTLING */
314 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
315 extern ssize_t
blk_throtl_sample_time_show(struct request_queue
*q
, char *page
);
316 extern ssize_t
blk_throtl_sample_time_store(struct request_queue
*q
,
317 const char *page
, size_t count
);
318 extern void blk_throtl_bio_endio(struct bio
*bio
);
319 extern void blk_throtl_stat_add(struct request
*rq
, u64 time
);
321 static inline void blk_throtl_bio_endio(struct bio
*bio
) { }
322 static inline void blk_throtl_stat_add(struct request
*rq
, u64 time
) { }
326 extern int init_emergency_isa_pool(void);
327 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
329 static inline int init_emergency_isa_pool(void)
333 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
336 #endif /* CONFIG_BOUNCE */
338 #endif /* BLK_INTERNAL_H */