xref: /openbmc/linux/block/blk.h (revision 6abeae2a)
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 static inline bool biovec_phys_mergeable(struct request_queue *q,
59 		struct bio_vec *vec1, struct bio_vec *vec2)
60 {
61 	unsigned long mask = queue_segment_boundary(q);
62 	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
63 	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
64 
65 	if (addr1 + vec1->bv_len != addr2)
66 		return false;
67 	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
68 		return false;
69 	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
70 		return false;
71 	return true;
72 }
73 
74 static inline bool __bvec_gap_to_prev(struct request_queue *q,
75 		struct bio_vec *bprv, unsigned int offset)
76 {
77 	return (offset & queue_virt_boundary(q)) ||
78 		((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
79 }
80 
81 /*
82  * Check if adding a bio_vec after bprv with offset would create a gap in
83  * the SG list. Most drivers don't care about this, but some do.
84  */
85 static inline bool bvec_gap_to_prev(struct request_queue *q,
86 		struct bio_vec *bprv, unsigned int offset)
87 {
88 	if (!queue_virt_boundary(q))
89 		return false;
90 	return __bvec_gap_to_prev(q, bprv, offset);
91 }
92 
93 #ifdef CONFIG_BLK_DEV_INTEGRITY
94 void blk_flush_integrity(void);
95 bool __bio_integrity_endio(struct bio *);
96 void bio_integrity_free(struct bio *bio);
97 static inline bool bio_integrity_endio(struct bio *bio)
98 {
99 	if (bio_integrity(bio))
100 		return __bio_integrity_endio(bio);
101 	return true;
102 }
103 
104 bool blk_integrity_merge_rq(struct request_queue *, struct request *,
105 		struct request *);
106 bool blk_integrity_merge_bio(struct request_queue *, struct request *,
107 		struct bio *);
108 
109 static inline bool integrity_req_gap_back_merge(struct request *req,
110 		struct bio *next)
111 {
112 	struct bio_integrity_payload *bip = bio_integrity(req->bio);
113 	struct bio_integrity_payload *bip_next = bio_integrity(next);
114 
115 	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
116 				bip_next->bip_vec[0].bv_offset);
117 }
118 
119 static inline bool integrity_req_gap_front_merge(struct request *req,
120 		struct bio *bio)
121 {
122 	struct bio_integrity_payload *bip = bio_integrity(bio);
123 	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
124 
125 	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
126 				bip_next->bip_vec[0].bv_offset);
127 }
128 
129 void blk_integrity_add(struct gendisk *);
130 void blk_integrity_del(struct gendisk *);
131 #else /* CONFIG_BLK_DEV_INTEGRITY */
132 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
133 		struct request *r1, struct request *r2)
134 {
135 	return true;
136 }
137 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
138 		struct request *r, struct bio *b)
139 {
140 	return true;
141 }
142 static inline bool integrity_req_gap_back_merge(struct request *req,
143 		struct bio *next)
144 {
145 	return false;
146 }
147 static inline bool integrity_req_gap_front_merge(struct request *req,
148 		struct bio *bio)
149 {
150 	return false;
151 }
152 
153 static inline void blk_flush_integrity(void)
154 {
155 }
156 static inline bool bio_integrity_endio(struct bio *bio)
157 {
158 	return true;
159 }
160 static inline void bio_integrity_free(struct bio *bio)
161 {
162 }
163 static inline void blk_integrity_add(struct gendisk *disk)
164 {
165 }
166 static inline void blk_integrity_del(struct gendisk *disk)
167 {
168 }
169 #endif /* CONFIG_BLK_DEV_INTEGRITY */
170 
171 unsigned long blk_rq_timeout(unsigned long timeout);
172 void blk_add_timer(struct request *req);
173 
174 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
175 		unsigned int nr_segs, struct request **same_queue_rq);
176 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
177 			struct bio *bio, unsigned int nr_segs);
178 
179 void blk_account_io_start(struct request *req);
180 void blk_account_io_done(struct request *req, u64 now);
181 
182 /*
183  * Internal elevator interface
184  */
185 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
186 
187 void blk_insert_flush(struct request *rq);
188 
189 void elevator_init_mq(struct request_queue *q);
190 int elevator_switch_mq(struct request_queue *q,
191 			      struct elevator_type *new_e);
192 void __elevator_exit(struct request_queue *, struct elevator_queue *);
193 int elv_register_queue(struct request_queue *q, bool uevent);
194 void elv_unregister_queue(struct request_queue *q);
195 
196 static inline void elevator_exit(struct request_queue *q,
197 		struct elevator_queue *e)
198 {
199 	lockdep_assert_held(&q->sysfs_lock);
200 
201 	blk_mq_sched_free_requests(q);
202 	__elevator_exit(q, e);
203 }
204 
205 struct block_device *__disk_get_part(struct gendisk *disk, int partno);
206 
207 ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
208 		char *buf);
209 ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
210 		char *buf);
211 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
212 		char *buf);
213 ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
214 		char *buf);
215 ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
216 		const char *buf, size_t count);
217 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
218 ssize_t part_timeout_store(struct device *, struct device_attribute *,
219 				const char *, size_t);
220 
221 void __blk_queue_split(struct bio **bio, unsigned int *nr_segs);
222 int ll_back_merge_fn(struct request *req, struct bio *bio,
223 		unsigned int nr_segs);
224 int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
225 				struct request *next);
226 unsigned int blk_recalc_rq_segments(struct request *rq);
227 void blk_rq_set_mixed_merge(struct request *rq);
228 bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
229 enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
230 
231 int blk_dev_init(void);
232 
233 /*
234  * Contribute to IO statistics IFF:
235  *
236  *	a) it's attached to a gendisk, and
237  *	b) the queue had IO stats enabled when this request was started
238  */
239 static inline bool blk_do_io_stat(struct request *rq)
240 {
241 	return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
242 }
243 
244 static inline void req_set_nomerge(struct request_queue *q, struct request *req)
245 {
246 	req->cmd_flags |= REQ_NOMERGE;
247 	if (req == q->last_merge)
248 		q->last_merge = NULL;
249 }
250 
251 /*
252  * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
253  * is defined as 'unsigned int', meantime it has to aligned to with logical
254  * block size which is the minimum accepted unit by hardware.
255  */
256 static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
257 {
258 	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
259 }
260 
261 /*
262  * The max bio size which is aligned to q->limits.discard_granularity. This
263  * is a hint to split large discard bio in generic block layer, then if device
264  * driver needs to split the discard bio into smaller ones, their bi_size can
265  * be very probably and easily aligned to discard_granularity of the device's
266  * queue.
267  */
268 static inline unsigned int bio_aligned_discard_max_sectors(
269 					struct request_queue *q)
270 {
271 	return round_down(UINT_MAX, q->limits.discard_granularity) >>
272 			SECTOR_SHIFT;
273 }
274 
275 /*
276  * Internal io_context interface
277  */
278 void get_io_context(struct io_context *ioc);
279 struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
280 struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
281 			     gfp_t gfp_mask);
282 void ioc_clear_queue(struct request_queue *q);
283 
284 int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
285 
286 /*
287  * Internal throttling interface
288  */
289 #ifdef CONFIG_BLK_DEV_THROTTLING
290 extern int blk_throtl_init(struct request_queue *q);
291 extern void blk_throtl_exit(struct request_queue *q);
292 extern void blk_throtl_register_queue(struct request_queue *q);
293 bool blk_throtl_bio(struct bio *bio);
294 #else /* CONFIG_BLK_DEV_THROTTLING */
295 static inline int blk_throtl_init(struct request_queue *q) { return 0; }
296 static inline void blk_throtl_exit(struct request_queue *q) { }
297 static inline void blk_throtl_register_queue(struct request_queue *q) { }
298 static inline bool blk_throtl_bio(struct bio *bio) { return false; }
299 #endif /* CONFIG_BLK_DEV_THROTTLING */
300 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
301 extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
302 extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
303 	const char *page, size_t count);
304 extern void blk_throtl_bio_endio(struct bio *bio);
305 extern void blk_throtl_stat_add(struct request *rq, u64 time);
306 #else
307 static inline void blk_throtl_bio_endio(struct bio *bio) { }
308 static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
309 #endif
310 
311 #ifdef CONFIG_BOUNCE
312 extern int init_emergency_isa_pool(void);
313 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
314 #else
315 static inline int init_emergency_isa_pool(void)
316 {
317 	return 0;
318 }
319 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
320 {
321 }
322 #endif /* CONFIG_BOUNCE */
323 
324 #ifdef CONFIG_BLK_CGROUP_IOLATENCY
325 extern int blk_iolatency_init(struct request_queue *q);
326 #else
327 static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
328 #endif
329 
330 struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
331 
332 #ifdef CONFIG_BLK_DEV_ZONED
333 void blk_queue_free_zone_bitmaps(struct request_queue *q);
334 #else
335 static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
336 #endif
337 
338 struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
339 
340 int blk_alloc_devt(struct block_device *part, dev_t *devt);
341 void blk_free_devt(dev_t devt);
342 char *disk_name(struct gendisk *hd, int partno, char *buf);
343 #define ADDPART_FLAG_NONE	0
344 #define ADDPART_FLAG_RAID	1
345 #define ADDPART_FLAG_WHOLEDISK	2
346 void delete_partition(struct block_device *part);
347 int bdev_add_partition(struct block_device *bdev, int partno,
348 		sector_t start, sector_t length);
349 int bdev_del_partition(struct block_device *bdev, int partno);
350 int bdev_resize_partition(struct block_device *bdev, int partno,
351 		sector_t start, sector_t length);
352 int disk_expand_part_tbl(struct gendisk *disk, int target);
353 
354 int bio_add_hw_page(struct request_queue *q, struct bio *bio,
355 		struct page *page, unsigned int len, unsigned int offset,
356 		unsigned int max_sectors, bool *same_page);
357 
358 #endif /* BLK_INTERNAL_H */
359