xref: /openbmc/linux/block/blk.h (revision 62eab49f)
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 <xen/xen.h>
10 #include "blk-crypto-internal.h"
11 #include "blk-mq.h"
12 #include "blk-mq-sched.h"
13 
14 /* Max future timer expiry for timeouts */
15 #define BLK_MAX_TIMEOUT		(5 * HZ)
16 
17 extern struct dentry *blk_debugfs_root;
18 
19 struct blk_flush_queue {
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 	spinlock_t		mq_flush_lock;
29 };
30 
31 extern struct kmem_cache *blk_requestq_cachep;
32 extern struct kobj_type blk_queue_ktype;
33 extern struct ida blk_queue_ida;
34 
35 static inline struct blk_flush_queue *
36 blk_get_flush_queue(struct request_queue *q, struct blk_mq_ctx *ctx)
37 {
38 	return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
39 }
40 
41 static inline void __blk_get_queue(struct request_queue *q)
42 {
43 	kobject_get(&q->kobj);
44 }
45 
46 static inline bool
47 is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
48 {
49 	return hctx->fq->flush_rq == req;
50 }
51 
52 struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
53 					      gfp_t flags);
54 void blk_free_flush_queue(struct blk_flush_queue *q);
55 
56 void blk_freeze_queue(struct request_queue *q);
57 
58 #define BIO_INLINE_VECS 4
59 struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
60 		gfp_t gfp_mask);
61 void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);
62 
63 static inline bool biovec_phys_mergeable(struct request_queue *q,
64 		struct bio_vec *vec1, struct bio_vec *vec2)
65 {
66 	unsigned long mask = queue_segment_boundary(q);
67 	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
68 	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
69 
70 	if (addr1 + vec1->bv_len != addr2)
71 		return false;
72 	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
73 		return false;
74 	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
75 		return false;
76 	return true;
77 }
78 
79 static inline bool __bvec_gap_to_prev(struct request_queue *q,
80 		struct bio_vec *bprv, unsigned int offset)
81 {
82 	return (offset & queue_virt_boundary(q)) ||
83 		((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
84 }
85 
86 /*
87  * Check if adding a bio_vec after bprv with offset would create a gap in
88  * the SG list. Most drivers don't care about this, but some do.
89  */
90 static inline bool bvec_gap_to_prev(struct request_queue *q,
91 		struct bio_vec *bprv, unsigned int offset)
92 {
93 	if (!queue_virt_boundary(q))
94 		return false;
95 	return __bvec_gap_to_prev(q, bprv, offset);
96 }
97 
98 #ifdef CONFIG_BLK_DEV_INTEGRITY
99 void blk_flush_integrity(void);
100 bool __bio_integrity_endio(struct bio *);
101 void bio_integrity_free(struct bio *bio);
102 static inline bool bio_integrity_endio(struct bio *bio)
103 {
104 	if (bio_integrity(bio))
105 		return __bio_integrity_endio(bio);
106 	return true;
107 }
108 
109 bool blk_integrity_merge_rq(struct request_queue *, struct request *,
110 		struct request *);
111 bool blk_integrity_merge_bio(struct request_queue *, struct request *,
112 		struct bio *);
113 
114 static 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 
124 static 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 
134 void blk_integrity_add(struct gendisk *);
135 void blk_integrity_del(struct gendisk *);
136 #else /* CONFIG_BLK_DEV_INTEGRITY */
137 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
138 		struct request *r1, struct request *r2)
139 {
140 	return true;
141 }
142 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
143 		struct request *r, struct bio *b)
144 {
145 	return true;
146 }
147 static inline bool integrity_req_gap_back_merge(struct request *req,
148 		struct bio *next)
149 {
150 	return false;
151 }
152 static inline bool integrity_req_gap_front_merge(struct request *req,
153 		struct bio *bio)
154 {
155 	return false;
156 }
157 
158 static inline void blk_flush_integrity(void)
159 {
160 }
161 static inline bool bio_integrity_endio(struct bio *bio)
162 {
163 	return true;
164 }
165 static inline void bio_integrity_free(struct bio *bio)
166 {
167 }
168 static inline void blk_integrity_add(struct gendisk *disk)
169 {
170 }
171 static inline void blk_integrity_del(struct gendisk *disk)
172 {
173 }
174 #endif /* CONFIG_BLK_DEV_INTEGRITY */
175 
176 unsigned long blk_rq_timeout(unsigned long timeout);
177 void blk_add_timer(struct request *req);
178 
179 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
180 		unsigned int nr_segs, struct request **same_queue_rq);
181 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
182 			struct bio *bio, unsigned int nr_segs);
183 
184 void blk_account_io_start(struct request *req);
185 void 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 
192 void blk_insert_flush(struct request *rq);
193 
194 void elevator_init_mq(struct request_queue *q);
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 int 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 #ifdef CONFIG_BOUNCE
315 extern int init_emergency_isa_pool(void);
316 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
317 #else
318 static inline int init_emergency_isa_pool(void)
319 {
320 	return 0;
321 }
322 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
323 {
324 }
325 #endif /* CONFIG_BOUNCE */
326 
327 #ifdef CONFIG_BLK_CGROUP_IOLATENCY
328 extern int blk_iolatency_init(struct request_queue *q);
329 #else
330 static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
331 #endif
332 
333 struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
334 
335 #ifdef CONFIG_BLK_DEV_ZONED
336 void blk_queue_free_zone_bitmaps(struct request_queue *q);
337 void blk_queue_clear_zone_settings(struct request_queue *q);
338 #else
339 static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
340 static inline void blk_queue_clear_zone_settings(struct request_queue *q) {}
341 #endif
342 
343 int blk_alloc_devt(struct block_device *part, dev_t *devt);
344 void blk_free_devt(dev_t devt);
345 char *disk_name(struct gendisk *hd, int partno, char *buf);
346 #define ADDPART_FLAG_NONE	0
347 #define ADDPART_FLAG_RAID	1
348 #define ADDPART_FLAG_WHOLEDISK	2
349 void delete_partition(struct block_device *part);
350 int bdev_add_partition(struct block_device *bdev, int partno,
351 		sector_t start, sector_t length);
352 int bdev_del_partition(struct block_device *bdev, int partno);
353 int bdev_resize_partition(struct block_device *bdev, int partno,
354 		sector_t start, sector_t length);
355 
356 int bio_add_hw_page(struct request_queue *q, struct bio *bio,
357 		struct page *page, unsigned int len, unsigned int offset,
358 		unsigned int max_sectors, bool *same_page);
359 
360 #endif /* BLK_INTERNAL_H */
361