tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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
10/* Max future timer expiry for timeouts */
11#define BLK_MAX_TIMEOUT (5 * HZ)
12
13#ifdef CONFIG_DEBUG_FS
14extern struct dentry *blk_debugfs_root;
15#endif
16
17struct blk_flush_queue {
18 unsigned int flush_queue_delayed:1;
19 unsigned int flush_pending_idx:1;
20 unsigned int flush_running_idx:1;
21 unsigned long flush_pending_since;
22 struct list_head flush_queue[2];
23 struct list_head flush_data_in_flight;
24 struct request *flush_rq;
25
26 /*
27 * flush_rq shares tag with this rq, both can't be active
28 * at the same time
29 */
30 struct request *orig_rq;
31 spinlock_t mq_flush_lock;
32};
33
34extern struct kmem_cache *blk_requestq_cachep;
35extern struct kobj_type blk_queue_ktype;
36extern struct ida blk_queue_ida;
37
38static inline struct blk_flush_queue *
39blk_get_flush_queue(struct request_queue *q, struct blk_mq_ctx *ctx)
40{
41 return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
42}
43
44static inline void __blk_get_queue(struct request_queue *q)
45{
46 kobject_get(&q->kobj);
47}
48
49struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
50 int node, int cmd_size, gfp_t flags);
51void blk_free_flush_queue(struct blk_flush_queue *q);
52
53void blk_exit_queue(struct request_queue *q);
54void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
55 struct bio *bio);
56void blk_freeze_queue(struct request_queue *q);
57
58static inline void blk_queue_enter_live(struct request_queue *q)
59{
60 /*
61 * Given that running in generic_make_request() context
62 * guarantees that a live reference against q_usage_counter has
63 * been established, further references under that same context
64 * need not check that the queue has been frozen (marked dead).
65 */
66 percpu_ref_get(&q->q_usage_counter);
67}
68
69static inline bool biovec_phys_mergeable(struct request_queue *q,
70 struct bio_vec *vec1, struct bio_vec *vec2)
71{
72 unsigned long mask = queue_segment_boundary(q);
73 phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
74 phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
75
76 if (addr1 + vec1->bv_len != addr2)
77 return false;
78 if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2))
79 return false;
80 if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
81 return false;
82 return true;
83}
84
85static inline bool __bvec_gap_to_prev(struct request_queue *q,
86 struct bio_vec *bprv, unsigned int offset)
87{
88 return (offset & queue_virt_boundary(q)) ||
89 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
90}
91
92/*
93 * Check if adding a bio_vec after bprv with offset would create a gap in
94 * the SG list. Most drivers don't care about this, but some do.
95 */
96static inline bool bvec_gap_to_prev(struct request_queue *q,
97 struct bio_vec *bprv, unsigned int offset)
98{
99 if (!queue_virt_boundary(q))
100 return false;
101 return __bvec_gap_to_prev(q, bprv, offset);
102}
103
104#ifdef CONFIG_BLK_DEV_INTEGRITY
105void blk_flush_integrity(void);
106bool __bio_integrity_endio(struct bio *);
107static inline bool bio_integrity_endio(struct bio *bio)
108{
109 if (bio_integrity(bio))
110 return __bio_integrity_endio(bio);
111 return true;
112}
113
114static inline bool integrity_req_gap_back_merge(struct request *req,
115 struct bio *next)
116{
117 struct bio_integrity_payload *bip = bio_integrity(req->bio);
118 struct bio_integrity_payload *bip_next = bio_integrity(next);
119
120 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
121 bip_next->bip_vec[0].bv_offset);
122}
123
124static inline bool integrity_req_gap_front_merge(struct request *req,
125 struct bio *bio)
126{
127 struct bio_integrity_payload *bip = bio_integrity(bio);
128 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
129
130 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
131 bip_next->bip_vec[0].bv_offset);
132}
133#else /* CONFIG_BLK_DEV_INTEGRITY */
134static inline bool integrity_req_gap_back_merge(struct request *req,
135 struct bio *next)
136{
137 return false;
138}
139static inline bool integrity_req_gap_front_merge(struct request *req,
140 struct bio *bio)
141{
142 return false;
143}
144
145static inline void blk_flush_integrity(void)
146{
147}
148static inline bool bio_integrity_endio(struct bio *bio)
149{
150 return true;
151}
152#endif /* CONFIG_BLK_DEV_INTEGRITY */
153
154unsigned long blk_rq_timeout(unsigned long timeout);
155void blk_add_timer(struct request *req);
156
157bool bio_attempt_front_merge(struct request_queue *q, struct request *req,
158 struct bio *bio);
159bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
160 struct bio *bio);
161bool bio_attempt_discard_merge(struct request_queue *q, struct request *req,
162 struct bio *bio);
163bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
164 struct request **same_queue_rq);
165
166void blk_account_io_start(struct request *req, bool new_io);
167void blk_account_io_completion(struct request *req, unsigned int bytes);
168void blk_account_io_done(struct request *req, u64 now);
169
170/*
171 * Internal elevator interface
172 */
173#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
174
175void blk_insert_flush(struct request *rq);
176
177int elevator_init_mq(struct request_queue *q);
178int elevator_switch_mq(struct request_queue *q,
179 struct elevator_type *new_e);
180void elevator_exit(struct request_queue *, struct elevator_queue *);
181int elv_register_queue(struct request_queue *q);
182void elv_unregister_queue(struct request_queue *q);
183
184struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
185
186#ifdef CONFIG_FAIL_IO_TIMEOUT
187int blk_should_fake_timeout(struct request_queue *);
188ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
189ssize_t part_timeout_store(struct device *, struct device_attribute *,
190 const char *, size_t);
191#else
192static inline int blk_should_fake_timeout(struct request_queue *q)
193{
194 return 0;
195}
196#endif
197
198int ll_back_merge_fn(struct request_queue *q, struct request *req,
199 struct bio *bio);
200int ll_front_merge_fn(struct request_queue *q, struct request *req,
201 struct bio *bio);
202struct request *attempt_back_merge(struct request_queue *q, struct request *rq);
203struct request *attempt_front_merge(struct request_queue *q, struct request *rq);
204int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
205 struct request *next);
206void blk_recalc_rq_segments(struct request *rq);
207void blk_rq_set_mixed_merge(struct request *rq);
208bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
209enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
210
211int blk_dev_init(void);
212
213/*
214 * Contribute to IO statistics IFF:
215 *
216 * a) it's attached to a gendisk, and
217 * b) the queue had IO stats enabled when this request was started, and
218 * c) it's a file system request
219 */
220static inline bool blk_do_io_stat(struct request *rq)
221{
222 return rq->rq_disk &&
223 (rq->rq_flags & RQF_IO_STAT) &&
224 !blk_rq_is_passthrough(rq);
225}
226
227static inline void req_set_nomerge(struct request_queue *q, struct request *req)
228{
229 req->cmd_flags |= REQ_NOMERGE;
230 if (req == q->last_merge)
231 q->last_merge = NULL;
232}
233
234/*
235 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
236 * is defined as 'unsigned int', meantime it has to aligned to with logical
237 * block size which is the minimum accepted unit by hardware.
238 */
239static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
240{
241 return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
242}
243
244/*
245 * Internal io_context interface
246 */
247void get_io_context(struct io_context *ioc);
248struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
249struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
250 gfp_t gfp_mask);
251void ioc_clear_queue(struct request_queue *q);
252
253int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
254
255/**
256 * create_io_context - try to create task->io_context
257 * @gfp_mask: allocation mask
258 * @node: allocation node
259 *
260 * If %current->io_context is %NULL, allocate a new io_context and install
261 * it. Returns the current %current->io_context which may be %NULL if
262 * allocation failed.
263 *
264 * Note that this function can't be called with IRQ disabled because
265 * task_lock which protects %current->io_context is IRQ-unsafe.
266 */
267static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
268{
269 WARN_ON_ONCE(irqs_disabled());
270 if (unlikely(!current->io_context))
271 create_task_io_context(current, gfp_mask, node);
272 return current->io_context;
273}
274
275/*
276 * Internal throttling interface
277 */
278#ifdef CONFIG_BLK_DEV_THROTTLING
279extern void blk_throtl_drain(struct request_queue *q);
280extern int blk_throtl_init(struct request_queue *q);
281extern void blk_throtl_exit(struct request_queue *q);
282extern void blk_throtl_register_queue(struct request_queue *q);
283#else /* CONFIG_BLK_DEV_THROTTLING */
284static inline void blk_throtl_drain(struct request_queue *q) { }
285static inline int blk_throtl_init(struct request_queue *q) { return 0; }
286static inline void blk_throtl_exit(struct request_queue *q) { }
287static inline void blk_throtl_register_queue(struct request_queue *q) { }
288#endif /* CONFIG_BLK_DEV_THROTTLING */
289#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
290extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
291extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
292 const char *page, size_t count);
293extern void blk_throtl_bio_endio(struct bio *bio);
294extern void blk_throtl_stat_add(struct request *rq, u64 time);
295#else
296static inline void blk_throtl_bio_endio(struct bio *bio) { }
297static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
298#endif
299
300#ifdef CONFIG_BOUNCE
301extern int init_emergency_isa_pool(void);
302extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
303#else
304static inline int init_emergency_isa_pool(void)
305{
306 return 0;
307}
308static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
309{
310}
311#endif /* CONFIG_BOUNCE */
312
313#ifdef CONFIG_BLK_CGROUP_IOLATENCY
314extern int blk_iolatency_init(struct request_queue *q);
315#else
316static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
317#endif
318
319struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
320
321#ifdef CONFIG_BLK_DEV_ZONED
322void blk_queue_free_zone_bitmaps(struct request_queue *q);
323#else
324static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
325#endif
326
327#endif /* BLK_INTERNAL_H */