1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef BLK_INTERNAL_H
3#define BLK_INTERNAL_H
4
5#include <linux/blk-crypto.h>
6#include <linux/memblock.h> /* for max_pfn/max_low_pfn */
7#include <xen/xen.h>
8#include "blk-crypto-internal.h"
9
10struct elevator_type;
11
12/* Max future timer expiry for timeouts */
13#define BLK_MAX_TIMEOUT (5 * HZ)
14
15extern struct dentry *blk_debugfs_root;
16
17struct blk_flush_queue {
18 spinlock_t mq_flush_lock;
19 unsigned int flush_pending_idx:1;
20 unsigned int flush_running_idx:1;
21 blk_status_t rq_status;
22 unsigned long flush_pending_since;
23 struct list_head flush_queue[2];
24 unsigned long flush_data_in_flight;
25 struct request *flush_rq;
26};
27
28bool is_flush_rq(struct request *req);
29
30struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
31 gfp_t flags);
32void blk_free_flush_queue(struct blk_flush_queue *q);
33
34void blk_freeze_queue(struct request_queue *q);
35void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
36void blk_queue_start_drain(struct request_queue *q);
37int __bio_queue_enter(struct request_queue *q, struct bio *bio);
38void submit_bio_noacct_nocheck(struct bio *bio);
39
40static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
41{
42 rcu_read_lock();
43 if (!percpu_ref_tryget_live_rcu(ref: &q->q_usage_counter))
44 goto fail;
45
46 /*
47 * The code that increments the pm_only counter must ensure that the
48 * counter is globally visible before the queue is unfrozen.
49 */
50 if (blk_queue_pm_only(q) &&
51 (!pm || queue_rpm_status(q) == RPM_SUSPENDED))
52 goto fail_put;
53
54 rcu_read_unlock();
55 return true;
56
57fail_put:
58 blk_queue_exit(q);
59fail:
60 rcu_read_unlock();
61 return false;
62}
63
64static inline int bio_queue_enter(struct bio *bio)
65{
66 struct request_queue *q = bdev_get_queue(bdev: bio->bi_bdev);
67
68 if (blk_try_enter_queue(q, pm: false))
69 return 0;
70 return __bio_queue_enter(q, bio);
71}
72
73#define BIO_INLINE_VECS 4
74struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
75 gfp_t gfp_mask);
76void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);
77
78bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv,
79 struct page *page, unsigned len, unsigned offset,
80 bool *same_page);
81
82static inline bool biovec_phys_mergeable(struct request_queue *q,
83 struct bio_vec *vec1, struct bio_vec *vec2)
84{
85 unsigned long mask = queue_segment_boundary(q);
86 phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
87 phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
88
89 /*
90 * Merging adjacent physical pages may not work correctly under KMSAN
91 * if their metadata pages aren't adjacent. Just disable merging.
92 */
93 if (IS_ENABLED(CONFIG_KMSAN))
94 return false;
95
96 if (addr1 + vec1->bv_len != addr2)
97 return false;
98 if (xen_domain() && !xen_biovec_phys_mergeable(vec1, page: vec2->bv_page))
99 return false;
100 if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
101 return false;
102 return true;
103}
104
105static inline bool __bvec_gap_to_prev(const struct queue_limits *lim,
106 struct bio_vec *bprv, unsigned int offset)
107{
108 return (offset & lim->virt_boundary_mask) ||
109 ((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask);
110}
111
112/*
113 * Check if adding a bio_vec after bprv with offset would create a gap in
114 * the SG list. Most drivers don't care about this, but some do.
115 */
116static inline bool bvec_gap_to_prev(const struct queue_limits *lim,
117 struct bio_vec *bprv, unsigned int offset)
118{
119 if (!lim->virt_boundary_mask)
120 return false;
121 return __bvec_gap_to_prev(lim, bprv, offset);
122}
123
124static inline bool rq_mergeable(struct request *rq)
125{
126 if (blk_rq_is_passthrough(rq))
127 return false;
128
129 if (req_op(req: rq) == REQ_OP_FLUSH)
130 return false;
131
132 if (req_op(req: rq) == REQ_OP_WRITE_ZEROES)
133 return false;
134
135 if (req_op(req: rq) == REQ_OP_ZONE_APPEND)
136 return false;
137
138 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
139 return false;
140 if (rq->rq_flags & RQF_NOMERGE_FLAGS)
141 return false;
142
143 return true;
144}
145
146/*
147 * There are two different ways to handle DISCARD merges:
148 * 1) If max_discard_segments > 1, the driver treats every bio as a range and
149 * send the bios to controller together. The ranges don't need to be
150 * contiguous.
151 * 2) Otherwise, the request will be normal read/write requests. The ranges
152 * need to be contiguous.
153 */
154static inline bool blk_discard_mergable(struct request *req)
155{
156 if (req_op(req) == REQ_OP_DISCARD &&
157 queue_max_discard_segments(q: req->q) > 1)
158 return true;
159 return false;
160}
161
162static inline unsigned int blk_rq_get_max_segments(struct request *rq)
163{
164 if (req_op(req: rq) == REQ_OP_DISCARD)
165 return queue_max_discard_segments(q: rq->q);
166 return queue_max_segments(q: rq->q);
167}
168
169static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
170 enum req_op op)
171{
172 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
173 return min(q->limits.max_discard_sectors,
174 UINT_MAX >> SECTOR_SHIFT);
175
176 if (unlikely(op == REQ_OP_WRITE_ZEROES))
177 return q->limits.max_write_zeroes_sectors;
178
179 return q->limits.max_sectors;
180}
181
182#ifdef CONFIG_BLK_DEV_INTEGRITY
183void blk_flush_integrity(void);
184bool __bio_integrity_endio(struct bio *);
185void bio_integrity_free(struct bio *bio);
186static inline bool bio_integrity_endio(struct bio *bio)
187{
188 if (bio_integrity(bio))
189 return __bio_integrity_endio(bio);
190 return true;
191}
192
193bool blk_integrity_merge_rq(struct request_queue *, struct request *,
194 struct request *);
195bool blk_integrity_merge_bio(struct request_queue *, struct request *,
196 struct bio *);
197
198static inline bool integrity_req_gap_back_merge(struct request *req,
199 struct bio *next)
200{
201 struct bio_integrity_payload *bip = bio_integrity(bio: req->bio);
202 struct bio_integrity_payload *bip_next = bio_integrity(bio: next);
203
204 return bvec_gap_to_prev(lim: &req->q->limits,
205 bprv: &bip->bip_vec[bip->bip_vcnt - 1],
206 offset: bip_next->bip_vec[0].bv_offset);
207}
208
209static inline bool integrity_req_gap_front_merge(struct request *req,
210 struct bio *bio)
211{
212 struct bio_integrity_payload *bip = bio_integrity(bio);
213 struct bio_integrity_payload *bip_next = bio_integrity(bio: req->bio);
214
215 return bvec_gap_to_prev(lim: &req->q->limits,
216 bprv: &bip->bip_vec[bip->bip_vcnt - 1],
217 offset: bip_next->bip_vec[0].bv_offset);
218}
219
220extern const struct attribute_group blk_integrity_attr_group;
221#else /* CONFIG_BLK_DEV_INTEGRITY */
222static inline bool blk_integrity_merge_rq(struct request_queue *rq,
223 struct request *r1, struct request *r2)
224{
225 return true;
226}
227static inline bool blk_integrity_merge_bio(struct request_queue *rq,
228 struct request *r, struct bio *b)
229{
230 return true;
231}
232static inline bool integrity_req_gap_back_merge(struct request *req,
233 struct bio *next)
234{
235 return false;
236}
237static inline bool integrity_req_gap_front_merge(struct request *req,
238 struct bio *bio)
239{
240 return false;
241}
242
243static inline void blk_flush_integrity(void)
244{
245}
246static inline bool bio_integrity_endio(struct bio *bio)
247{
248 return true;
249}
250static inline void bio_integrity_free(struct bio *bio)
251{
252}
253#endif /* CONFIG_BLK_DEV_INTEGRITY */
254
255unsigned long blk_rq_timeout(unsigned long timeout);
256void blk_add_timer(struct request *req);
257
258bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
259 unsigned int nr_segs);
260bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
261 struct bio *bio, unsigned int nr_segs);
262
263/*
264 * Plug flush limits
265 */
266#define BLK_MAX_REQUEST_COUNT 32
267#define BLK_PLUG_FLUSH_SIZE (128 * 1024)
268
269/*
270 * Internal elevator interface
271 */
272#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
273
274bool blk_insert_flush(struct request *rq);
275
276int elevator_switch(struct request_queue *q, struct elevator_type *new_e);
277void elevator_disable(struct request_queue *q);
278void elevator_exit(struct request_queue *q);
279int elv_register_queue(struct request_queue *q, bool uevent);
280void elv_unregister_queue(struct request_queue *q);
281
282ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
283 char *buf);
284ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
285 char *buf);
286ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
287 char *buf);
288ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
289 char *buf);
290ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
291 const char *buf, size_t count);
292ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
293ssize_t part_timeout_store(struct device *, struct device_attribute *,
294 const char *, size_t);
295
296static inline bool bio_may_exceed_limits(struct bio *bio,
297 const struct queue_limits *lim)
298{
299 switch (bio_op(bio)) {
300 case REQ_OP_DISCARD:
301 case REQ_OP_SECURE_ERASE:
302 case REQ_OP_WRITE_ZEROES:
303 return true; /* non-trivial splitting decisions */
304 default:
305 break;
306 }
307
308 /*
309 * All drivers must accept single-segments bios that are <= PAGE_SIZE.
310 * This is a quick and dirty check that relies on the fact that
311 * bi_io_vec[0] is always valid if a bio has data. The check might
312 * lead to occasional false negatives when bios are cloned, but compared
313 * to the performance impact of cloned bios themselves the loop below
314 * doesn't matter anyway.
315 */
316 return lim->chunk_sectors || bio->bi_vcnt != 1 ||
317 bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
318}
319
320struct bio *__bio_split_to_limits(struct bio *bio,
321 const struct queue_limits *lim,
322 unsigned int *nr_segs);
323int ll_back_merge_fn(struct request *req, struct bio *bio,
324 unsigned int nr_segs);
325bool blk_attempt_req_merge(struct request_queue *q, struct request *rq,
326 struct request *next);
327unsigned int blk_recalc_rq_segments(struct request *rq);
328void blk_rq_set_mixed_merge(struct request *rq);
329bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
330enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
331
332void blk_set_default_limits(struct queue_limits *lim);
333int blk_dev_init(void);
334
335/*
336 * Contribute to IO statistics IFF:
337 *
338 * a) it's attached to a gendisk, and
339 * b) the queue had IO stats enabled when this request was started
340 */
341static inline bool blk_do_io_stat(struct request *rq)
342{
343 return (rq->rq_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq);
344}
345
346void update_io_ticks(struct block_device *part, unsigned long now, bool end);
347
348static inline void req_set_nomerge(struct request_queue *q, struct request *req)
349{
350 req->cmd_flags |= REQ_NOMERGE;
351 if (req == q->last_merge)
352 q->last_merge = NULL;
353}
354
355/*
356 * Internal io_context interface
357 */
358struct io_cq *ioc_find_get_icq(struct request_queue *q);
359struct io_cq *ioc_lookup_icq(struct request_queue *q);
360#ifdef CONFIG_BLK_ICQ
361void ioc_clear_queue(struct request_queue *q);
362#else
363static inline void ioc_clear_queue(struct request_queue *q)
364{
365}
366#endif /* CONFIG_BLK_ICQ */
367
368#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
369extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
370extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
371 const char *page, size_t count);
372extern void blk_throtl_bio_endio(struct bio *bio);
373extern void blk_throtl_stat_add(struct request *rq, u64 time);
374#else
375static inline void blk_throtl_bio_endio(struct bio *bio) { }
376static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
377#endif
378
379struct bio *__blk_queue_bounce(struct bio *bio, struct request_queue *q);
380
381static inline bool blk_queue_may_bounce(struct request_queue *q)
382{
383 return IS_ENABLED(CONFIG_BOUNCE) &&
384 q->limits.bounce == BLK_BOUNCE_HIGH &&
385 max_low_pfn >= max_pfn;
386}
387
388static inline struct bio *blk_queue_bounce(struct bio *bio,
389 struct request_queue *q)
390{
391 if (unlikely(blk_queue_may_bounce(q) && bio_has_data(bio)))
392 return __blk_queue_bounce(bio, q);
393 return bio;
394}
395
396#ifdef CONFIG_BLK_DEV_ZONED
397void disk_free_zone_bitmaps(struct gendisk *disk);
398void disk_clear_zone_settings(struct gendisk *disk);
399int blkdev_report_zones_ioctl(struct block_device *bdev, unsigned int cmd,
400 unsigned long arg);
401int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode,
402 unsigned int cmd, unsigned long arg);
403#else /* CONFIG_BLK_DEV_ZONED */
404static inline void disk_free_zone_bitmaps(struct gendisk *disk) {}
405static inline void disk_clear_zone_settings(struct gendisk *disk) {}
406static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
407 unsigned int cmd, unsigned long arg)
408{
409 return -ENOTTY;
410}
411static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
412 blk_mode_t mode, unsigned int cmd, unsigned long arg)
413{
414 return -ENOTTY;
415}
416#endif /* CONFIG_BLK_DEV_ZONED */
417
418struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
419void bdev_add(struct block_device *bdev, dev_t dev);
420
421int blk_alloc_ext_minor(void);
422void blk_free_ext_minor(unsigned int minor);
423#define ADDPART_FLAG_NONE 0
424#define ADDPART_FLAG_RAID 1
425#define ADDPART_FLAG_WHOLEDISK 2
426int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
427 sector_t length);
428int bdev_del_partition(struct gendisk *disk, int partno);
429int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
430 sector_t length);
431void drop_partition(struct block_device *part);
432
433void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors);
434
435struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
436 struct lock_class_key *lkclass);
437
438int bio_add_hw_page(struct request_queue *q, struct bio *bio,
439 struct page *page, unsigned int len, unsigned int offset,
440 unsigned int max_sectors, bool *same_page);
441
442/*
443 * Clean up a page appropriately, where the page may be pinned, may have a
444 * ref taken on it or neither.
445 */
446static inline void bio_release_page(struct bio *bio, struct page *page)
447{
448 if (bio_flagged(bio, bit: BIO_PAGE_PINNED))
449 unpin_user_page(page);
450}
451
452struct request_queue *blk_alloc_queue(int node_id);
453
454int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode);
455
456int disk_alloc_events(struct gendisk *disk);
457void disk_add_events(struct gendisk *disk);
458void disk_del_events(struct gendisk *disk);
459void disk_release_events(struct gendisk *disk);
460void disk_block_events(struct gendisk *disk);
461void disk_unblock_events(struct gendisk *disk);
462void disk_flush_events(struct gendisk *disk, unsigned int mask);
463extern struct device_attribute dev_attr_events;
464extern struct device_attribute dev_attr_events_async;
465extern struct device_attribute dev_attr_events_poll_msecs;
466
467extern struct attribute_group blk_trace_attr_group;
468
469blk_mode_t file_to_blk_mode(struct file *file);
470int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
471 loff_t lstart, loff_t lend);
472long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
473long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
474
475extern const struct address_space_operations def_blk_aops;
476
477int disk_register_independent_access_ranges(struct gendisk *disk);
478void disk_unregister_independent_access_ranges(struct gendisk *disk);
479
480#ifdef CONFIG_FAIL_MAKE_REQUEST
481bool should_fail_request(struct block_device *part, unsigned int bytes);
482#else /* CONFIG_FAIL_MAKE_REQUEST */
483static inline bool should_fail_request(struct block_device *part,
484 unsigned int bytes)
485{
486 return false;
487}
488#endif /* CONFIG_FAIL_MAKE_REQUEST */
489
490/*
491 * Optimized request reference counting. Ideally we'd make timeouts be more
492 * clever, as that's the only reason we need references at all... But until
493 * this happens, this is faster than using refcount_t. Also see:
494 *
495 * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count")
496 */
497#define req_ref_zero_or_close_to_overflow(req) \
498 ((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u)
499
500static inline bool req_ref_inc_not_zero(struct request *req)
501{
502 return atomic_inc_not_zero(v: &req->ref);
503}
504
505static inline bool req_ref_put_and_test(struct request *req)
506{
507 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
508 return atomic_dec_and_test(v: &req->ref);
509}
510
511static inline void req_ref_set(struct request *req, int value)
512{
513 atomic_set(v: &req->ref, i: value);
514}
515
516static inline int req_ref_read(struct request *req)
517{
518 return atomic_read(v: &req->ref);
519}
520
521#endif /* BLK_INTERNAL_H */
522

source code of linux/block/blk.h