xref: /linux/block/blk.h (revision 94e48d6aafef23143f92eadd010c505c49487576)
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 <linux/part_stat.h>
8 #include <linux/blk-crypto.h>
9 #include <linux/memblock.h>	/* for max_pfn/max_low_pfn */
10 #include <xen/xen.h>
11 #include "blk-crypto-internal.h"
12 #include "blk-mq.h"
13 #include "blk-mq-sched.h"
14 
15 /* Max future timer expiry for timeouts */
16 #define BLK_MAX_TIMEOUT		(5 * HZ)
17 
18 extern struct dentry *blk_debugfs_root;
19 
20 struct blk_flush_queue {
21 	unsigned int		flush_pending_idx:1;
22 	unsigned int		flush_running_idx:1;
23 	blk_status_t 		rq_status;
24 	unsigned long		flush_pending_since;
25 	struct list_head	flush_queue[2];
26 	struct list_head	flush_data_in_flight;
27 	struct request		*flush_rq;
28 
29 	spinlock_t		mq_flush_lock;
30 };
31 
32 extern struct kmem_cache *blk_requestq_cachep;
33 extern struct kobj_type blk_queue_ktype;
34 extern struct ida blk_queue_ida;
35 
36 static inline struct blk_flush_queue *
37 blk_get_flush_queue(struct request_queue *q, struct blk_mq_ctx *ctx)
38 {
39 	return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
40 }
41 
42 static inline void __blk_get_queue(struct request_queue *q)
43 {
44 	kobject_get(&q->kobj);
45 }
46 
47 static inline bool
48 is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
49 {
50 	return hctx->fq->flush_rq == req;
51 }
52 
53 struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
54 					      gfp_t flags);
55 void blk_free_flush_queue(struct blk_flush_queue *q);
56 
57 void blk_freeze_queue(struct request_queue *q);
58 
59 #define BIO_INLINE_VECS 4
60 struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
61 		gfp_t gfp_mask);
62 void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);
63 
64 static inline bool biovec_phys_mergeable(struct request_queue *q,
65 		struct bio_vec *vec1, struct bio_vec *vec2)
66 {
67 	unsigned long mask = queue_segment_boundary(q);
68 	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
69 	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
70 
71 	if (addr1 + vec1->bv_len != addr2)
72 		return false;
73 	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
74 		return false;
75 	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
76 		return false;
77 	return true;
78 }
79 
80 static inline bool __bvec_gap_to_prev(struct request_queue *q,
81 		struct bio_vec *bprv, unsigned int offset)
82 {
83 	return (offset & queue_virt_boundary(q)) ||
84 		((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
85 }
86 
87 /*
88  * Check if adding a bio_vec after bprv with offset would create a gap in
89  * the SG list. Most drivers don't care about this, but some do.
90  */
91 static inline bool bvec_gap_to_prev(struct request_queue *q,
92 		struct bio_vec *bprv, unsigned int offset)
93 {
94 	if (!queue_virt_boundary(q))
95 		return false;
96 	return __bvec_gap_to_prev(q, bprv, offset);
97 }
98 
99 #ifdef CONFIG_BLK_DEV_INTEGRITY
100 void blk_flush_integrity(void);
101 bool __bio_integrity_endio(struct bio *);
102 void bio_integrity_free(struct bio *bio);
103 static inline bool bio_integrity_endio(struct bio *bio)
104 {
105 	if (bio_integrity(bio))
106 		return __bio_integrity_endio(bio);
107 	return true;
108 }
109 
110 bool blk_integrity_merge_rq(struct request_queue *, struct request *,
111 		struct request *);
112 bool blk_integrity_merge_bio(struct request_queue *, struct request *,
113 		struct bio *);
114 
115 static inline bool integrity_req_gap_back_merge(struct request *req,
116 		struct bio *next)
117 {
118 	struct bio_integrity_payload *bip = bio_integrity(req->bio);
119 	struct bio_integrity_payload *bip_next = bio_integrity(next);
120 
121 	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
122 				bip_next->bip_vec[0].bv_offset);
123 }
124 
125 static inline bool integrity_req_gap_front_merge(struct request *req,
126 		struct bio *bio)
127 {
128 	struct bio_integrity_payload *bip = bio_integrity(bio);
129 	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
130 
131 	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
132 				bip_next->bip_vec[0].bv_offset);
133 }
134 
135 void blk_integrity_add(struct gendisk *);
136 void blk_integrity_del(struct gendisk *);
137 #else /* CONFIG_BLK_DEV_INTEGRITY */
138 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
139 		struct request *r1, struct request *r2)
140 {
141 	return true;
142 }
143 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
144 		struct request *r, struct bio *b)
145 {
146 	return true;
147 }
148 static inline bool integrity_req_gap_back_merge(struct request *req,
149 		struct bio *next)
150 {
151 	return false;
152 }
153 static inline bool integrity_req_gap_front_merge(struct request *req,
154 		struct bio *bio)
155 {
156 	return false;
157 }
158 
159 static inline void blk_flush_integrity(void)
160 {
161 }
162 static inline bool bio_integrity_endio(struct bio *bio)
163 {
164 	return true;
165 }
166 static inline void bio_integrity_free(struct bio *bio)
167 {
168 }
169 static inline void blk_integrity_add(struct gendisk *disk)
170 {
171 }
172 static inline void blk_integrity_del(struct gendisk *disk)
173 {
174 }
175 #endif /* CONFIG_BLK_DEV_INTEGRITY */
176 
177 unsigned long blk_rq_timeout(unsigned long timeout);
178 void blk_add_timer(struct request *req);
179 
180 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
181 		unsigned int nr_segs, struct request **same_queue_rq);
182 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
183 			struct bio *bio, unsigned int nr_segs);
184 
185 void blk_account_io_start(struct request *req);
186 void blk_account_io_done(struct request *req, u64 now);
187 
188 /*
189  * Internal elevator interface
190  */
191 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
192 
193 void blk_insert_flush(struct request *rq);
194 
195 int elevator_switch_mq(struct request_queue *q,
196 			      struct elevator_type *new_e);
197 void __elevator_exit(struct request_queue *, struct elevator_queue *);
198 int elv_register_queue(struct request_queue *q, bool uevent);
199 void elv_unregister_queue(struct request_queue *q);
200 
201 static 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 
210 ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
211 		char *buf);
212 ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
213 		char *buf);
214 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
215 		char *buf);
216 ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
217 		char *buf);
218 ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
219 		const char *buf, size_t count);
220 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
221 ssize_t part_timeout_store(struct device *, struct device_attribute *,
222 				const char *, size_t);
223 
224 void __blk_queue_split(struct bio **bio, unsigned int *nr_segs);
225 int ll_back_merge_fn(struct request *req, struct bio *bio,
226 		unsigned int nr_segs);
227 bool blk_attempt_req_merge(struct request_queue *q, struct request *rq,
228 				struct request *next);
229 unsigned int blk_recalc_rq_segments(struct request *rq);
230 void blk_rq_set_mixed_merge(struct request *rq);
231 bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
232 enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
233 
234 int blk_dev_init(void);
235 
236 /*
237  * Contribute to IO statistics IFF:
238  *
239  *	a) it's attached to a gendisk, and
240  *	b) the queue had IO stats enabled when this request was started
241  */
242 static inline bool blk_do_io_stat(struct request *rq)
243 {
244 	return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
245 }
246 
247 static inline void req_set_nomerge(struct request_queue *q, struct request *req)
248 {
249 	req->cmd_flags |= REQ_NOMERGE;
250 	if (req == q->last_merge)
251 		q->last_merge = NULL;
252 }
253 
254 /*
255  * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
256  * is defined as 'unsigned int', meantime it has to aligned to with logical
257  * block size which is the minimum accepted unit by hardware.
258  */
259 static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
260 {
261 	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
262 }
263 
264 /*
265  * The max bio size which is aligned to q->limits.discard_granularity. This
266  * is a hint to split large discard bio in generic block layer, then if device
267  * driver needs to split the discard bio into smaller ones, their bi_size can
268  * be very probably and easily aligned to discard_granularity of the device's
269  * queue.
270  */
271 static inline unsigned int bio_aligned_discard_max_sectors(
272 					struct request_queue *q)
273 {
274 	return round_down(UINT_MAX, q->limits.discard_granularity) >>
275 			SECTOR_SHIFT;
276 }
277 
278 /*
279  * Internal io_context interface
280  */
281 void get_io_context(struct io_context *ioc);
282 struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
283 struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
284 			     gfp_t gfp_mask);
285 void ioc_clear_queue(struct request_queue *q);
286 
287 int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
288 
289 /*
290  * Internal throttling interface
291  */
292 #ifdef CONFIG_BLK_DEV_THROTTLING
293 extern int blk_throtl_init(struct request_queue *q);
294 extern void blk_throtl_exit(struct request_queue *q);
295 extern void blk_throtl_register_queue(struct request_queue *q);
296 bool blk_throtl_bio(struct bio *bio);
297 #else /* CONFIG_BLK_DEV_THROTTLING */
298 static inline int blk_throtl_init(struct request_queue *q) { return 0; }
299 static inline void blk_throtl_exit(struct request_queue *q) { }
300 static inline void blk_throtl_register_queue(struct request_queue *q) { }
301 static inline bool blk_throtl_bio(struct bio *bio) { return false; }
302 #endif /* CONFIG_BLK_DEV_THROTTLING */
303 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
304 extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
305 extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
306 	const char *page, size_t count);
307 extern void blk_throtl_bio_endio(struct bio *bio);
308 extern void blk_throtl_stat_add(struct request *rq, u64 time);
309 #else
310 static inline void blk_throtl_bio_endio(struct bio *bio) { }
311 static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
312 #endif
313 
314 void __blk_queue_bounce(struct request_queue *q, struct bio **bio);
315 
316 static inline bool blk_queue_may_bounce(struct request_queue *q)
317 {
318 	return IS_ENABLED(CONFIG_BOUNCE) &&
319 		q->limits.bounce == BLK_BOUNCE_HIGH &&
320 		max_low_pfn >= max_pfn;
321 }
322 
323 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
324 {
325 	if (unlikely(blk_queue_may_bounce(q) && bio_has_data(*bio)))
326 		__blk_queue_bounce(q, bio);
327 }
328 
329 #ifdef CONFIG_BLK_CGROUP_IOLATENCY
330 extern int blk_iolatency_init(struct request_queue *q);
331 #else
332 static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
333 #endif
334 
335 struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
336 
337 #ifdef CONFIG_BLK_DEV_ZONED
338 void blk_queue_free_zone_bitmaps(struct request_queue *q);
339 void blk_queue_clear_zone_settings(struct request_queue *q);
340 #else
341 static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
342 static inline void blk_queue_clear_zone_settings(struct request_queue *q) {}
343 #endif
344 
345 int blk_alloc_ext_minor(void);
346 void blk_free_ext_minor(unsigned int minor);
347 char *disk_name(struct gendisk *hd, int partno, char *buf);
348 #define ADDPART_FLAG_NONE	0
349 #define ADDPART_FLAG_RAID	1
350 #define ADDPART_FLAG_WHOLEDISK	2
351 int bdev_add_partition(struct block_device *bdev, int partno,
352 		sector_t start, sector_t length);
353 int bdev_del_partition(struct block_device *bdev, int partno);
354 int bdev_resize_partition(struct block_device *bdev, int partno,
355 		sector_t start, sector_t length);
356 
357 int bio_add_hw_page(struct request_queue *q, struct bio *bio,
358 		struct page *page, unsigned int len, unsigned int offset,
359 		unsigned int max_sectors, bool *same_page);
360 
361 struct request_queue *blk_alloc_queue(int node_id);
362 
363 void disk_alloc_events(struct gendisk *disk);
364 void disk_add_events(struct gendisk *disk);
365 void disk_del_events(struct gendisk *disk);
366 void disk_release_events(struct gendisk *disk);
367 extern struct device_attribute dev_attr_events;
368 extern struct device_attribute dev_attr_events_async;
369 extern struct device_attribute dev_attr_events_poll_msecs;
370 
371 #endif /* BLK_INTERNAL_H */
372