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1#ifndef BLK_INTERNAL_H
2#define BLK_INTERNAL_H
3
4#include <linux/idr.h>
5
6/* Amount of time in which a process may batch requests */
7#define BLK_BATCH_TIME (HZ/50UL)
8
9/* Number of requests a "batching" process may submit */
10#define BLK_BATCH_REQ 32
11
12extern struct kmem_cache *blk_requestq_cachep;
13extern struct kobj_type blk_queue_ktype;
14extern struct ida blk_queue_ida;
15
16static inline void __blk_get_queue(struct request_queue *q)
17{
18 kobject_get(&q->kobj);
19}
20
21void init_request_from_bio(struct request *req, struct bio *bio);
22void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
23 struct bio *bio);
24int blk_rq_append_bio(struct request_queue *q, struct request *rq,
25 struct bio *bio);
26void blk_queue_bypass_start(struct request_queue *q);
27void blk_queue_bypass_end(struct request_queue *q);
28void blk_dequeue_request(struct request *rq);
29void __blk_queue_free_tags(struct request_queue *q);
30bool __blk_end_bidi_request(struct request *rq, int error,
31 unsigned int nr_bytes, unsigned int bidi_bytes);
32
33void blk_rq_timed_out_timer(unsigned long data);
34void blk_delete_timer(struct request *);
35void blk_add_timer(struct request *);
36void __generic_unplug_device(struct request_queue *);
37
38/*
39 * Internal atomic flags for request handling
40 */
41enum rq_atomic_flags {
42 REQ_ATOM_COMPLETE = 0,
43};
44
45/*
46 * EH timer and IO completion will both attempt to 'grab' the request, make
47 * sure that only one of them succeeds
48 */
49static inline int blk_mark_rq_complete(struct request *rq)
50{
51 return test_and_set_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
52}
53
54static inline void blk_clear_rq_complete(struct request *rq)
55{
56 clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
57}
58
59/*
60 * Internal elevator interface
61 */
62#define ELV_ON_HASH(rq) (!hlist_unhashed(&(rq)->hash))
63
64void blk_insert_flush(struct request *rq);
65void blk_abort_flushes(struct request_queue *q);
66
67static inline struct request *__elv_next_request(struct request_queue *q)
68{
69 struct request *rq;
70
71 while (1) {
72 if (!list_empty(&q->queue_head)) {
73 rq = list_entry_rq(q->queue_head.next);
74 return rq;
75 }
76
77 /*
78 * Flush request is running and flush request isn't queueable
79 * in the drive, we can hold the queue till flush request is
80 * finished. Even we don't do this, driver can't dispatch next
81 * requests and will requeue them. And this can improve
82 * throughput too. For example, we have request flush1, write1,
83 * flush 2. flush1 is dispatched, then queue is hold, write1
84 * isn't inserted to queue. After flush1 is finished, flush2
85 * will be dispatched. Since disk cache is already clean,
86 * flush2 will be finished very soon, so looks like flush2 is
87 * folded to flush1.
88 * Since the queue is hold, a flag is set to indicate the queue
89 * should be restarted later. Please see flush_end_io() for
90 * details.
91 */
92 if (q->flush_pending_idx != q->flush_running_idx &&
93 !queue_flush_queueable(q)) {
94 q->flush_queue_delayed = 1;
95 return NULL;
96 }
97 if (unlikely(blk_queue_dead(q)) ||
98 !q->elevator->type->ops.elevator_dispatch_fn(q, 0))
99 return NULL;
100 }
101}
102
103static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
104{
105 struct elevator_queue *e = q->elevator;
106
107 if (e->type->ops.elevator_activate_req_fn)
108 e->type->ops.elevator_activate_req_fn(q, rq);
109}
110
111static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq)
112{
113 struct elevator_queue *e = q->elevator;
114
115 if (e->type->ops.elevator_deactivate_req_fn)
116 e->type->ops.elevator_deactivate_req_fn(q, rq);
117}
118
119#ifdef CONFIG_FAIL_IO_TIMEOUT
120int blk_should_fake_timeout(struct request_queue *);
121ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
122ssize_t part_timeout_store(struct device *, struct device_attribute *,
123 const char *, size_t);
124#else
125static inline int blk_should_fake_timeout(struct request_queue *q)
126{
127 return 0;
128}
129#endif
130
131int ll_back_merge_fn(struct request_queue *q, struct request *req,
132 struct bio *bio);
133int ll_front_merge_fn(struct request_queue *q, struct request *req,
134 struct bio *bio);
135int attempt_back_merge(struct request_queue *q, struct request *rq);
136int attempt_front_merge(struct request_queue *q, struct request *rq);
137int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
138 struct request *next);
139void blk_recalc_rq_segments(struct request *rq);
140void blk_rq_set_mixed_merge(struct request *rq);
141bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
142int blk_try_merge(struct request *rq, struct bio *bio);
143
144void blk_queue_congestion_threshold(struct request_queue *q);
145
146int blk_dev_init(void);
147
148
149/*
150 * Return the threshold (number of used requests) at which the queue is
151 * considered to be congested. It include a little hysteresis to keep the
152 * context switch rate down.
153 */
154static inline int queue_congestion_on_threshold(struct request_queue *q)
155{
156 return q->nr_congestion_on;
157}
158
159/*
160 * The threshold at which a queue is considered to be uncongested
161 */
162static inline int queue_congestion_off_threshold(struct request_queue *q)
163{
164 return q->nr_congestion_off;
165}
166
167/*
168 * Contribute to IO statistics IFF:
169 *
170 * a) it's attached to a gendisk, and
171 * b) the queue had IO stats enabled when this request was started, and
172 * c) it's a file system request or a discard request
173 */
174static inline int blk_do_io_stat(struct request *rq)
175{
176 return rq->rq_disk &&
177 (rq->cmd_flags & REQ_IO_STAT) &&
178 (rq->cmd_type == REQ_TYPE_FS ||
179 (rq->cmd_flags & REQ_DISCARD));
180}
181
182/*
183 * Internal io_context interface
184 */
185void get_io_context(struct io_context *ioc);
186struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
187struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
188 gfp_t gfp_mask);
189void ioc_clear_queue(struct request_queue *q);
190
191int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
192
193/**
194 * create_io_context - try to create task->io_context
195 * @gfp_mask: allocation mask
196 * @node: allocation node
197 *
198 * If %current->io_context is %NULL, allocate a new io_context and install
199 * it. Returns the current %current->io_context which may be %NULL if
200 * allocation failed.
201 *
202 * Note that this function can't be called with IRQ disabled because
203 * task_lock which protects %current->io_context is IRQ-unsafe.
204 */
205static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
206{
207 WARN_ON_ONCE(irqs_disabled());
208 if (unlikely(!current->io_context))
209 create_task_io_context(current, gfp_mask, node);
210 return current->io_context;
211}
212
213/*
214 * Internal throttling interface
215 */
216#ifdef CONFIG_BLK_DEV_THROTTLING
217extern bool blk_throtl_bio(struct request_queue *q, struct bio *bio);
218extern void blk_throtl_drain(struct request_queue *q);
219extern int blk_throtl_init(struct request_queue *q);
220extern void blk_throtl_exit(struct request_queue *q);
221#else /* CONFIG_BLK_DEV_THROTTLING */
222static inline bool blk_throtl_bio(struct request_queue *q, struct bio *bio)
223{
224 return false;
225}
226static inline void blk_throtl_drain(struct request_queue *q) { }
227static inline int blk_throtl_init(struct request_queue *q) { return 0; }
228static inline void blk_throtl_exit(struct request_queue *q) { }
229#endif /* CONFIG_BLK_DEV_THROTTLING */
230
231#endif /* BLK_INTERNAL_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef BLK_INTERNAL_H
3#define BLK_INTERNAL_H
4
5#include <linux/idr.h>
6#include <linux/blk-mq.h>
7#include <xen/xen.h>
8#include "blk-mq.h"
9#include "blk-mq-sched.h"
10
11/* Max future timer expiry for timeouts */
12#define BLK_MAX_TIMEOUT (5 * HZ)
13
14#ifdef CONFIG_DEBUG_FS
15extern struct dentry *blk_debugfs_root;
16#endif
17
18struct blk_flush_queue {
19 unsigned int flush_queue_delayed:1;
20 unsigned int flush_pending_idx:1;
21 unsigned int flush_running_idx:1;
22 blk_status_t rq_status;
23 unsigned long flush_pending_since;
24 struct list_head flush_queue[2];
25 struct list_head flush_data_in_flight;
26 struct request *flush_rq;
27
28 /*
29 * flush_rq shares tag with this rq, both can't be active
30 * at the same time
31 */
32 struct request *orig_rq;
33 spinlock_t mq_flush_lock;
34};
35
36extern struct kmem_cache *blk_requestq_cachep;
37extern struct kobj_type blk_queue_ktype;
38extern struct ida blk_queue_ida;
39
40static inline struct blk_flush_queue *
41blk_get_flush_queue(struct request_queue *q, struct blk_mq_ctx *ctx)
42{
43 return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
44}
45
46static inline void __blk_get_queue(struct request_queue *q)
47{
48 kobject_get(&q->kobj);
49}
50
51static inline bool
52is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
53{
54 return hctx->fq->flush_rq == req;
55}
56
57struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
58 int node, int cmd_size, gfp_t flags);
59void blk_free_flush_queue(struct blk_flush_queue *q);
60
61void blk_freeze_queue(struct request_queue *q);
62
63static inline void blk_queue_enter_live(struct request_queue *q)
64{
65 /*
66 * Given that running in generic_make_request() context
67 * guarantees that a live reference against q_usage_counter has
68 * been established, further references under that same context
69 * need not check that the queue has been frozen (marked dead).
70 */
71 percpu_ref_get(&q->q_usage_counter);
72}
73
74static inline bool biovec_phys_mergeable(struct request_queue *q,
75 struct bio_vec *vec1, struct bio_vec *vec2)
76{
77 unsigned long mask = queue_segment_boundary(q);
78 phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
79 phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
80
81 if (addr1 + vec1->bv_len != addr2)
82 return false;
83 if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
84 return false;
85 if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
86 return false;
87 return true;
88}
89
90static inline bool __bvec_gap_to_prev(struct request_queue *q,
91 struct bio_vec *bprv, unsigned int offset)
92{
93 return (offset & queue_virt_boundary(q)) ||
94 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
95}
96
97/*
98 * Check if adding a bio_vec after bprv with offset would create a gap in
99 * the SG list. Most drivers don't care about this, but some do.
100 */
101static inline bool bvec_gap_to_prev(struct request_queue *q,
102 struct bio_vec *bprv, unsigned int offset)
103{
104 if (!queue_virt_boundary(q))
105 return false;
106 return __bvec_gap_to_prev(q, bprv, offset);
107}
108
109static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
110 unsigned int nr_segs)
111{
112 rq->nr_phys_segments = nr_segs;
113 rq->__data_len = bio->bi_iter.bi_size;
114 rq->bio = rq->biotail = bio;
115 rq->ioprio = bio_prio(bio);
116
117 if (bio->bi_disk)
118 rq->rq_disk = bio->bi_disk;
119}
120
121#ifdef CONFIG_BLK_DEV_INTEGRITY
122void blk_flush_integrity(void);
123bool __bio_integrity_endio(struct bio *);
124static inline bool bio_integrity_endio(struct bio *bio)
125{
126 if (bio_integrity(bio))
127 return __bio_integrity_endio(bio);
128 return true;
129}
130
131static inline bool integrity_req_gap_back_merge(struct request *req,
132 struct bio *next)
133{
134 struct bio_integrity_payload *bip = bio_integrity(req->bio);
135 struct bio_integrity_payload *bip_next = bio_integrity(next);
136
137 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
138 bip_next->bip_vec[0].bv_offset);
139}
140
141static inline bool integrity_req_gap_front_merge(struct request *req,
142 struct bio *bio)
143{
144 struct bio_integrity_payload *bip = bio_integrity(bio);
145 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
146
147 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
148 bip_next->bip_vec[0].bv_offset);
149}
150#else /* CONFIG_BLK_DEV_INTEGRITY */
151static inline bool integrity_req_gap_back_merge(struct request *req,
152 struct bio *next)
153{
154 return false;
155}
156static inline bool integrity_req_gap_front_merge(struct request *req,
157 struct bio *bio)
158{
159 return false;
160}
161
162static inline void blk_flush_integrity(void)
163{
164}
165static inline bool bio_integrity_endio(struct bio *bio)
166{
167 return true;
168}
169#endif /* CONFIG_BLK_DEV_INTEGRITY */
170
171unsigned long blk_rq_timeout(unsigned long timeout);
172void blk_add_timer(struct request *req);
173
174bool bio_attempt_front_merge(struct request *req, struct bio *bio,
175 unsigned int nr_segs);
176bool bio_attempt_back_merge(struct request *req, struct bio *bio,
177 unsigned int nr_segs);
178bool bio_attempt_discard_merge(struct request_queue *q, struct request *req,
179 struct bio *bio);
180bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
181 unsigned int nr_segs, struct request **same_queue_rq);
182
183void blk_account_io_start(struct request *req, bool new_io);
184void blk_account_io_completion(struct request *req, unsigned int bytes);
185void blk_account_io_done(struct request *req, u64 now);
186
187/*
188 * Internal elevator interface
189 */
190#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
191
192void blk_insert_flush(struct request *rq);
193
194void elevator_init_mq(struct request_queue *q);
195int elevator_switch_mq(struct request_queue *q,
196 struct elevator_type *new_e);
197void __elevator_exit(struct request_queue *, struct elevator_queue *);
198int elv_register_queue(struct request_queue *q, bool uevent);
199void elv_unregister_queue(struct request_queue *q);
200
201static inline void elevator_exit(struct request_queue *q,
202 struct elevator_queue *e)
203{
204 lockdep_assert_held(&q->sysfs_lock);
205
206 blk_mq_sched_free_requests(q);
207 __elevator_exit(q, e);
208}
209
210struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
211
212#ifdef CONFIG_FAIL_IO_TIMEOUT
213int blk_should_fake_timeout(struct request_queue *);
214ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
215ssize_t part_timeout_store(struct device *, struct device_attribute *,
216 const char *, size_t);
217#else
218static inline int blk_should_fake_timeout(struct request_queue *q)
219{
220 return 0;
221}
222#endif
223
224void __blk_queue_split(struct request_queue *q, struct bio **bio,
225 unsigned int *nr_segs);
226int ll_back_merge_fn(struct request *req, struct bio *bio,
227 unsigned int nr_segs);
228int ll_front_merge_fn(struct request *req, struct bio *bio,
229 unsigned int nr_segs);
230struct request *attempt_back_merge(struct request_queue *q, struct request *rq);
231struct request *attempt_front_merge(struct request_queue *q, struct request *rq);
232int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
233 struct request *next);
234unsigned int blk_recalc_rq_segments(struct request *rq);
235void blk_rq_set_mixed_merge(struct request *rq);
236bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
237enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
238
239int blk_dev_init(void);
240
241/*
242 * Contribute to IO statistics IFF:
243 *
244 * a) it's attached to a gendisk, and
245 * b) the queue had IO stats enabled when this request was started, and
246 * c) it's a file system request
247 */
248static inline bool blk_do_io_stat(struct request *rq)
249{
250 return rq->rq_disk &&
251 (rq->rq_flags & RQF_IO_STAT) &&
252 !blk_rq_is_passthrough(rq);
253}
254
255static inline void req_set_nomerge(struct request_queue *q, struct request *req)
256{
257 req->cmd_flags |= REQ_NOMERGE;
258 if (req == q->last_merge)
259 q->last_merge = NULL;
260}
261
262/*
263 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
264 * is defined as 'unsigned int', meantime it has to aligned to with logical
265 * block size which is the minimum accepted unit by hardware.
266 */
267static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
268{
269 return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
270}
271
272/*
273 * Internal io_context interface
274 */
275void get_io_context(struct io_context *ioc);
276struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
277struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
278 gfp_t gfp_mask);
279void ioc_clear_queue(struct request_queue *q);
280
281int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
282
283/**
284 * create_io_context - try to create task->io_context
285 * @gfp_mask: allocation mask
286 * @node: allocation node
287 *
288 * If %current->io_context is %NULL, allocate a new io_context and install
289 * it. Returns the current %current->io_context which may be %NULL if
290 * allocation failed.
291 *
292 * Note that this function can't be called with IRQ disabled because
293 * task_lock which protects %current->io_context is IRQ-unsafe.
294 */
295static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
296{
297 WARN_ON_ONCE(irqs_disabled());
298 if (unlikely(!current->io_context))
299 create_task_io_context(current, gfp_mask, node);
300 return current->io_context;
301}
302
303/*
304 * Internal throttling interface
305 */
306#ifdef CONFIG_BLK_DEV_THROTTLING
307extern void blk_throtl_drain(struct request_queue *q);
308extern int blk_throtl_init(struct request_queue *q);
309extern void blk_throtl_exit(struct request_queue *q);
310extern void blk_throtl_register_queue(struct request_queue *q);
311#else /* CONFIG_BLK_DEV_THROTTLING */
312static inline void blk_throtl_drain(struct request_queue *q) { }
313static inline int blk_throtl_init(struct request_queue *q) { return 0; }
314static inline void blk_throtl_exit(struct request_queue *q) { }
315static inline void blk_throtl_register_queue(struct request_queue *q) { }
316#endif /* CONFIG_BLK_DEV_THROTTLING */
317#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
318extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
319extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
320 const char *page, size_t count);
321extern void blk_throtl_bio_endio(struct bio *bio);
322extern void blk_throtl_stat_add(struct request *rq, u64 time);
323#else
324static inline void blk_throtl_bio_endio(struct bio *bio) { }
325static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
326#endif
327
328#ifdef CONFIG_BOUNCE
329extern int init_emergency_isa_pool(void);
330extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
331#else
332static inline int init_emergency_isa_pool(void)
333{
334 return 0;
335}
336static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
337{
338}
339#endif /* CONFIG_BOUNCE */
340
341#ifdef CONFIG_BLK_CGROUP_IOLATENCY
342extern int blk_iolatency_init(struct request_queue *q);
343#else
344static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
345#endif
346
347struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
348
349#ifdef CONFIG_BLK_DEV_ZONED
350void blk_queue_free_zone_bitmaps(struct request_queue *q);
351#else
352static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
353#endif
354
355#endif /* BLK_INTERNAL_H */