LXR linux/block/blk.h

   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
  17extern struct dentry *blk_debugfs_root;
  18
  19struct 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        struct lock_class_key   key;
  29        spinlock_t              mq_flush_lock;
  30};
  31
  32extern struct kmem_cache *blk_requestq_cachep;
  33extern struct kobj_type blk_queue_ktype;
  34extern struct ida blk_queue_ida;
  35
  36static inline struct blk_flush_queue *
  37blk_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
  42static inline void __blk_get_queue(struct request_queue *q)
  43{
  44        kobject_get(&q->kobj);
  45}
  46
  47static inline bool
  48is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
  49{
  50        return hctx->fq->flush_rq == req;
  51}
  52
  53struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
  54                                              gfp_t flags);
  55void blk_free_flush_queue(struct blk_flush_queue *q);
  56
  57void blk_freeze_queue(struct request_queue *q);
  58
  59static inline bool biovec_phys_mergeable(struct request_queue *q,
  60                struct bio_vec *vec1, struct bio_vec *vec2)
  61{
  62        unsigned long mask = queue_segment_boundary(q);
  63        phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
  64        phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
  65
  66        if (addr1 + vec1->bv_len != addr2)
  67                return false;
  68        if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
  69                return false;
  70        if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
  71                return false;
  72        return true;
  73}
  74
  75static inline bool __bvec_gap_to_prev(struct request_queue *q,
  76                struct bio_vec *bprv, unsigned int offset)
  77{
  78        return (offset & queue_virt_boundary(q)) ||
  79                ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
  80}
  81
  82/*
  83 * Check if adding a bio_vec after bprv with offset would create a gap in
  84 * the SG list. Most drivers don't care about this, but some do.
  85 */
  86static inline bool bvec_gap_to_prev(struct request_queue *q,
  87                struct bio_vec *bprv, unsigned int offset)
  88{
  89        if (!queue_virt_boundary(q))
  90                return false;
  91        return __bvec_gap_to_prev(q, bprv, offset);
  92}
  93
  94static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
  95                unsigned int nr_segs)
  96{
  97        rq->nr_phys_segments = nr_segs;
  98        rq->__data_len = bio->bi_iter.bi_size;
  99        rq->bio = rq->biotail = bio;
 100        rq->ioprio = bio_prio(bio);
 101
 102        if (bio->bi_disk)
 103                rq->rq_disk = bio->bi_disk;
 104}
 105
 106#ifdef CONFIG_BLK_DEV_INTEGRITY
 107void blk_flush_integrity(void);
 108bool __bio_integrity_endio(struct bio *);
 109void bio_integrity_free(struct bio *bio);
 110static inline bool bio_integrity_endio(struct bio *bio)
 111{
 112        if (bio_integrity(bio))
 113                return __bio_integrity_endio(bio);
 114        return true;
 115}
 116
 117static inline bool integrity_req_gap_back_merge(struct request *req,
 118                struct bio *next)
 119{
 120        struct bio_integrity_payload *bip = bio_integrity(req->bio);
 121        struct bio_integrity_payload *bip_next = bio_integrity(next);
 122
 123        return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
 124                                bip_next->bip_vec[0].bv_offset);
 125}
 126
 127static inline bool integrity_req_gap_front_merge(struct request *req,
 128                struct bio *bio)
 129{
 130        struct bio_integrity_payload *bip = bio_integrity(bio);
 131        struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
 132
 133        return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
 134                                bip_next->bip_vec[0].bv_offset);
 135}
 136
 137void blk_integrity_add(struct gendisk *);
 138void blk_integrity_del(struct gendisk *);
 139#else /* CONFIG_BLK_DEV_INTEGRITY */
 140static inline bool integrity_req_gap_back_merge(struct request *req,
 141                struct bio *next)
 142{
 143        return false;
 144}
 145static inline bool integrity_req_gap_front_merge(struct request *req,
 146                struct bio *bio)
 147{
 148        return false;
 149}
 150
 151static inline void blk_flush_integrity(void)
 152{
 153}
 154static inline bool bio_integrity_endio(struct bio *bio)
 155{
 156        return true;
 157}
 158static inline void bio_integrity_free(struct bio *bio)
 159{
 160}
 161static inline void blk_integrity_add(struct gendisk *disk)
 162{
 163}
 164static inline void blk_integrity_del(struct gendisk *disk)
 165{
 166}
 167#endif /* CONFIG_BLK_DEV_INTEGRITY */
 168
 169unsigned long blk_rq_timeout(unsigned long timeout);
 170void blk_add_timer(struct request *req);
 171
 172bool bio_attempt_front_merge(struct request *req, struct bio *bio,
 173                unsigned int nr_segs);
 174bool bio_attempt_back_merge(struct request *req, struct bio *bio,
 175                unsigned int nr_segs);
 176bool bio_attempt_discard_merge(struct request_queue *q, struct request *req,
 177                struct bio *bio);
 178bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
 179                unsigned int nr_segs, struct request **same_queue_rq);
 180
 181void blk_account_io_start(struct request *req);
 182void blk_account_io_done(struct request *req, u64 now);
 183
 184/*
 185 * Internal elevator interface
 186 */
 187#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
 188
 189void blk_insert_flush(struct request *rq);
 190
 191void elevator_init_mq(struct request_queue *q);
 192int elevator_switch_mq(struct request_queue *q,
 193                              struct elevator_type *new_e);
 194void __elevator_exit(struct request_queue *, struct elevator_queue *);
 195int elv_register_queue(struct request_queue *q, bool uevent);
 196void elv_unregister_queue(struct request_queue *q);
 197
 198static inline void elevator_exit(struct request_queue *q,
 199                struct elevator_queue *e)
 200{
 201        lockdep_assert_held(&q->sysfs_lock);
 202
 203        blk_mq_sched_free_requests(q);
 204        __elevator_exit(q, e);
 205}
 206
 207struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 208
 209ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
 210                char *buf);
 211ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
 212                char *buf);
 213ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
 214                char *buf);
 215ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
 216                char *buf);
 217ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
 218                const char *buf, size_t count);
 219ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
 220ssize_t part_timeout_store(struct device *, struct device_attribute *,
 221                                const char *, size_t);
 222
 223void __blk_queue_split(struct bio **bio, unsigned int *nr_segs);
 224int ll_back_merge_fn(struct request *req, struct bio *bio,
 225                unsigned int nr_segs);
 226int ll_front_merge_fn(struct request *req,  struct bio *bio,
 227                unsigned int nr_segs);
 228struct request *attempt_back_merge(struct request_queue *q, struct request *rq);
 229struct request *attempt_front_merge(struct request_queue *q, struct request *rq);
 230int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
 231                                struct request *next);
 232unsigned int blk_recalc_rq_segments(struct request *rq);
 233void blk_rq_set_mixed_merge(struct request *rq);
 234bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
 235enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
 236
 237int blk_dev_init(void);
 238
 239/*
 240 * Contribute to IO statistics IFF:
 241 *
 242 *      a) it's attached to a gendisk, and
 243 *      b) the queue had IO stats enabled when this request was started
 244 */
 245static inline bool blk_do_io_stat(struct request *rq)
 246{
 247        return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
 248}
 249
 250static inline void req_set_nomerge(struct request_queue *q, struct request *req)
 251{
 252        req->cmd_flags |= REQ_NOMERGE;
 253        if (req == q->last_merge)
 254                q->last_merge = NULL;
 255}
 256
 257/*
 258 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
 259 * is defined as 'unsigned int', meantime it has to aligned to with logical
 260 * block size which is the minimum accepted unit by hardware.
 261 */
 262static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
 263{
 264        return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
 265}
 266
 267/*
 268 * The max bio size which is aligned to q->limits.discard_granularity. This
 269 * is a hint to split large discard bio in generic block layer, then if device
 270 * driver needs to split the discard bio into smaller ones, their bi_size can
 271 * be very probably and easily aligned to discard_granularity of the device's
 272 * queue.
 273 */
 274static inline unsigned int bio_aligned_discard_max_sectors(
 275                                        struct request_queue *q)
 276{
 277        return round_down(UINT_MAX, q->limits.discard_granularity) >>
 278                        SECTOR_SHIFT;
 279}
 280
 281/*
 282 * Internal io_context interface
 283 */
 284void get_io_context(struct io_context *ioc);
 285struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
 286struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
 287                             gfp_t gfp_mask);
 288void ioc_clear_queue(struct request_queue *q);
 289
 290int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
 291
 292/*
 293 * Internal throttling interface
 294 */
 295#ifdef CONFIG_BLK_DEV_THROTTLING
 296extern int blk_throtl_init(struct request_queue *q);
 297extern void blk_throtl_exit(struct request_queue *q);
 298extern void blk_throtl_register_queue(struct request_queue *q);
 299bool blk_throtl_bio(struct bio *bio);
 300#else /* CONFIG_BLK_DEV_THROTTLING */
 301static inline int blk_throtl_init(struct request_queue *q) { return 0; }
 302static inline void blk_throtl_exit(struct request_queue *q) { }
 303static inline void blk_throtl_register_queue(struct request_queue *q) { }
 304static inline bool blk_throtl_bio(struct bio *bio) { return false; }
 305#endif /* CONFIG_BLK_DEV_THROTTLING */
 306#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 307extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
 308extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
 309        const char *page, size_t count);
 310extern void blk_throtl_bio_endio(struct bio *bio);
 311extern void blk_throtl_stat_add(struct request *rq, u64 time);
 312#else
 313static inline void blk_throtl_bio_endio(struct bio *bio) { }
 314static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
 315#endif
 316
 317#ifdef CONFIG_BOUNCE
 318extern int init_emergency_isa_pool(void);
 319extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
 320#else
 321static inline int init_emergency_isa_pool(void)
 322{
 323        return 0;
 324}
 325static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
 326{
 327}
 328#endif /* CONFIG_BOUNCE */
 329
 330#ifdef CONFIG_BLK_CGROUP_IOLATENCY
 331extern int blk_iolatency_init(struct request_queue *q);
 332#else
 333static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
 334#endif
 335
 336struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
 337
 338#ifdef CONFIG_BLK_DEV_ZONED
 339void blk_queue_free_zone_bitmaps(struct request_queue *q);
 340#else
 341static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
 342#endif
 343
 344struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
 345
 346int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 347void blk_free_devt(dev_t devt);
 348void blk_invalidate_devt(dev_t devt);
 349char *disk_name(struct gendisk *hd, int partno, char *buf);
 350#define ADDPART_FLAG_NONE       0
 351#define ADDPART_FLAG_RAID       1
 352#define ADDPART_FLAG_WHOLEDISK  2
 353void delete_partition(struct gendisk *disk, struct hd_struct *part);
 354int bdev_add_partition(struct block_device *bdev, int partno,
 355                sector_t start, sector_t length);
 356int bdev_del_partition(struct block_device *bdev, int partno);
 357int bdev_resize_partition(struct block_device *bdev, int partno,
 358                sector_t start, sector_t length);
 359int disk_expand_part_tbl(struct gendisk *disk, int target);
 360int hd_ref_init(struct hd_struct *part);
 361
 362/* no need to get/put refcount of part0 */
 363static inline int hd_struct_try_get(struct hd_struct *part)
 364{
 365        if (part->partno)
 366                return percpu_ref_tryget_live(&part->ref);
 367        return 1;
 368}
 369
 370static inline void hd_struct_put(struct hd_struct *part)
 371{
 372        if (part->partno)
 373                percpu_ref_put(&part->ref);
 374}
 375
 376static inline void hd_free_part(struct hd_struct *part)
 377{
 378        free_percpu(part->dkstats);
 379        kfree(part->info);
 380        percpu_ref_exit(&part->ref);
 381}
 382
 383/*
 384 * Any access of part->nr_sects which is not protected by partition
 385 * bd_mutex or gendisk bdev bd_mutex, should be done using this
 386 * accessor function.
 387 *
 388 * Code written along the lines of i_size_read() and i_size_write().
 389 * CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
 390 * on.
 391 */
 392static inline sector_t part_nr_sects_read(struct hd_struct *part)
 393{
 394#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 395        sector_t nr_sects;
 396        unsigned seq;
 397        do {
 398                seq = read_seqcount_begin(&part->nr_sects_seq);
 399                nr_sects = part->nr_sects;
 400        } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 401        return nr_sects;
 402#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 403        sector_t nr_sects;
 404
 405        preempt_disable();
 406        nr_sects = part->nr_sects;
 407        preempt_enable();
 408        return nr_sects;
 409#else
 410        return part->nr_sects;
 411#endif
 412}
 413
 414/*
 415 * Should be called with mutex lock held (typically bd_mutex) of partition
 416 * to provide mutual exlusion among writers otherwise seqcount might be
 417 * left in wrong state leaving the readers spinning infinitely.
 418 */
 419static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 420{
 421#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 422        preempt_disable();
 423        write_seqcount_begin(&part->nr_sects_seq);
 424        part->nr_sects = size;
 425        write_seqcount_end(&part->nr_sects_seq);
 426        preempt_enable();
 427#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 428        preempt_disable();
 429        part->nr_sects = size;
 430        preempt_enable();
 431#else
 432        part->nr_sects = size;
 433#endif
 434}
 435
 436int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 437                struct page *page, unsigned int len, unsigned int offset,
 438                unsigned int max_sectors, bool *same_page);
 439
 440#endif /* BLK_INTERNAL_H */
 441