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TOMOYO Linux Cross Reference
Linux/include/linux/blkdev.h

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  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 #ifndef _LINUX_BLKDEV_H
  3 #define _LINUX_BLKDEV_H
  4 
  5 #include <linux/sched.h>
  6 #include <linux/sched/clock.h>
  7 
  8 #ifdef CONFIG_BLOCK
  9 
 10 #include <linux/major.h>
 11 #include <linux/genhd.h>
 12 #include <linux/list.h>
 13 #include <linux/llist.h>
 14 #include <linux/timer.h>
 15 #include <linux/workqueue.h>
 16 #include <linux/pagemap.h>
 17 #include <linux/backing-dev-defs.h>
 18 #include <linux/wait.h>
 19 #include <linux/mempool.h>
 20 #include <linux/pfn.h>
 21 #include <linux/bio.h>
 22 #include <linux/stringify.h>
 23 #include <linux/gfp.h>
 24 #include <linux/bsg.h>
 25 #include <linux/smp.h>
 26 #include <linux/rcupdate.h>
 27 #include <linux/percpu-refcount.h>
 28 #include <linux/scatterlist.h>
 29 #include <linux/blkzoned.h>
 30 
 31 struct module;
 32 struct scsi_ioctl_command;
 33 
 34 struct request_queue;
 35 struct elevator_queue;
 36 struct blk_trace;
 37 struct request;
 38 struct sg_io_hdr;
 39 struct bsg_job;
 40 struct blkcg_gq;
 41 struct blk_flush_queue;
 42 struct pr_ops;
 43 struct rq_qos;
 44 struct blk_queue_stats;
 45 struct blk_stat_callback;
 46 
 47 #define BLKDEV_MIN_RQ   4
 48 #define BLKDEV_MAX_RQ   128     /* Default maximum */
 49 
 50 /* Must be consistent with blk_mq_poll_stats_bkt() */
 51 #define BLK_MQ_POLL_STATS_BKTS 16
 52 
 53 /*
 54  * Maximum number of blkcg policies allowed to be registered concurrently.
 55  * Defined here to simplify include dependency.
 56  */
 57 #define BLKCG_MAX_POLS          5
 58 
 59 typedef void (rq_end_io_fn)(struct request *, blk_status_t);
 60 
 61 /*
 62  * request flags */
 63 typedef __u32 __bitwise req_flags_t;
 64 
 65 /* elevator knows about this request */
 66 #define RQF_SORTED              ((__force req_flags_t)(1 << 0))
 67 /* drive already may have started this one */
 68 #define RQF_STARTED             ((__force req_flags_t)(1 << 1))
 69 /* may not be passed by ioscheduler */
 70 #define RQF_SOFTBARRIER         ((__force req_flags_t)(1 << 3))
 71 /* request for flush sequence */
 72 #define RQF_FLUSH_SEQ           ((__force req_flags_t)(1 << 4))
 73 /* merge of different types, fail separately */
 74 #define RQF_MIXED_MERGE         ((__force req_flags_t)(1 << 5))
 75 /* track inflight for MQ */
 76 #define RQF_MQ_INFLIGHT         ((__force req_flags_t)(1 << 6))
 77 /* don't call prep for this one */
 78 #define RQF_DONTPREP            ((__force req_flags_t)(1 << 7))
 79 /* set for "ide_preempt" requests and also for requests for which the SCSI
 80    "quiesce" state must be ignored. */
 81 #define RQF_PREEMPT             ((__force req_flags_t)(1 << 8))
 82 /* contains copies of user pages */
 83 #define RQF_COPY_USER           ((__force req_flags_t)(1 << 9))
 84 /* vaguely specified driver internal error.  Ignored by the block layer */
 85 #define RQF_FAILED              ((__force req_flags_t)(1 << 10))
 86 /* don't warn about errors */
 87 #define RQF_QUIET               ((__force req_flags_t)(1 << 11))
 88 /* elevator private data attached */
 89 #define RQF_ELVPRIV             ((__force req_flags_t)(1 << 12))
 90 /* account into disk and partition IO statistics */
 91 #define RQF_IO_STAT             ((__force req_flags_t)(1 << 13))
 92 /* request came from our alloc pool */
 93 #define RQF_ALLOCED             ((__force req_flags_t)(1 << 14))
 94 /* runtime pm request */
 95 #define RQF_PM                  ((__force req_flags_t)(1 << 15))
 96 /* on IO scheduler merge hash */
 97 #define RQF_HASHED              ((__force req_flags_t)(1 << 16))
 98 /* track IO completion time */
 99 #define RQF_STATS               ((__force req_flags_t)(1 << 17))
100 /* Look at ->special_vec for the actual data payload instead of the
101    bio chain. */
102 #define RQF_SPECIAL_PAYLOAD     ((__force req_flags_t)(1 << 18))
103 /* The per-zone write lock is held for this request */
104 #define RQF_ZONE_WRITE_LOCKED   ((__force req_flags_t)(1 << 19))
105 /* already slept for hybrid poll */
106 #define RQF_MQ_POLL_SLEPT       ((__force req_flags_t)(1 << 20))
107 /* ->timeout has been called, don't expire again */
108 #define RQF_TIMED_OUT           ((__force req_flags_t)(1 << 21))
109 
110 /* flags that prevent us from merging requests: */
111 #define RQF_NOMERGE_FLAGS \
112         (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
113 
114 /*
115  * Request state for blk-mq.
116  */
117 enum mq_rq_state {
118         MQ_RQ_IDLE              = 0,
119         MQ_RQ_IN_FLIGHT         = 1,
120         MQ_RQ_COMPLETE          = 2,
121 };
122 
123 /*
124  * Try to put the fields that are referenced together in the same cacheline.
125  *
126  * If you modify this structure, make sure to update blk_rq_init() and
127  * especially blk_mq_rq_ctx_init() to take care of the added fields.
128  */
129 struct request {
130         struct request_queue *q;
131         struct blk_mq_ctx *mq_ctx;
132         struct blk_mq_hw_ctx *mq_hctx;
133 
134         unsigned int cmd_flags;         /* op and common flags */
135         req_flags_t rq_flags;
136 
137         int internal_tag;
138 
139         /* the following two fields are internal, NEVER access directly */
140         unsigned int __data_len;        /* total data len */
141         int tag;
142         sector_t __sector;              /* sector cursor */
143 
144         struct bio *bio;
145         struct bio *biotail;
146 
147         struct list_head queuelist;
148 
149         /*
150          * The hash is used inside the scheduler, and killed once the
151          * request reaches the dispatch list. The ipi_list is only used
152          * to queue the request for softirq completion, which is long
153          * after the request has been unhashed (and even removed from
154          * the dispatch list).
155          */
156         union {
157                 struct hlist_node hash; /* merge hash */
158                 struct list_head ipi_list;
159         };
160 
161         /*
162          * The rb_node is only used inside the io scheduler, requests
163          * are pruned when moved to the dispatch queue. So let the
164          * completion_data share space with the rb_node.
165          */
166         union {
167                 struct rb_node rb_node; /* sort/lookup */
168                 struct bio_vec special_vec;
169                 void *completion_data;
170                 int error_count; /* for legacy drivers, don't use */
171         };
172 
173         /*
174          * Three pointers are available for the IO schedulers, if they need
175          * more they have to dynamically allocate it.  Flush requests are
176          * never put on the IO scheduler. So let the flush fields share
177          * space with the elevator data.
178          */
179         union {
180                 struct {
181                         struct io_cq            *icq;
182                         void                    *priv[2];
183                 } elv;
184 
185                 struct {
186                         unsigned int            seq;
187                         struct list_head        list;
188                         rq_end_io_fn            *saved_end_io;
189                 } flush;
190         };
191 
192         struct gendisk *rq_disk;
193         struct hd_struct *part;
194         /* Time that I/O was submitted to the kernel. */
195         u64 start_time_ns;
196         /* Time that I/O was submitted to the device. */
197         u64 io_start_time_ns;
198 
199 #ifdef CONFIG_BLK_WBT
200         unsigned short wbt_flags;
201 #endif
202 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
203         unsigned short throtl_size;
204 #endif
205 
206         /*
207          * Number of scatter-gather DMA addr+len pairs after
208          * physical address coalescing is performed.
209          */
210         unsigned short nr_phys_segments;
211 
212 #if defined(CONFIG_BLK_DEV_INTEGRITY)
213         unsigned short nr_integrity_segments;
214 #endif
215 
216         unsigned short write_hint;
217         unsigned short ioprio;
218 
219         void *special;          /* opaque pointer available for LLD use */
220 
221         unsigned int extra_len; /* length of alignment and padding */
222 
223         enum mq_rq_state state;
224         refcount_t ref;
225 
226         unsigned int timeout;
227         unsigned long deadline;
228 
229         union {
230                 struct __call_single_data csd;
231                 u64 fifo_time;
232         };
233 
234         /*
235          * completion callback.
236          */
237         rq_end_io_fn *end_io;
238         void *end_io_data;
239 
240         /* for bidi */
241         struct request *next_rq;
242 };
243 
244 static inline bool blk_op_is_scsi(unsigned int op)
245 {
246         return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
247 }
248 
249 static inline bool blk_op_is_private(unsigned int op)
250 {
251         return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
252 }
253 
254 static inline bool blk_rq_is_scsi(struct request *rq)
255 {
256         return blk_op_is_scsi(req_op(rq));
257 }
258 
259 static inline bool blk_rq_is_private(struct request *rq)
260 {
261         return blk_op_is_private(req_op(rq));
262 }
263 
264 static inline bool blk_rq_is_passthrough(struct request *rq)
265 {
266         return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
267 }
268 
269 static inline bool bio_is_passthrough(struct bio *bio)
270 {
271         unsigned op = bio_op(bio);
272 
273         return blk_op_is_scsi(op) || blk_op_is_private(op);
274 }
275 
276 static inline unsigned short req_get_ioprio(struct request *req)
277 {
278         return req->ioprio;
279 }
280 
281 #include <linux/elevator.h>
282 
283 struct blk_queue_ctx;
284 
285 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
286 
287 struct bio_vec;
288 typedef int (dma_drain_needed_fn)(struct request *);
289 
290 enum blk_eh_timer_return {
291         BLK_EH_DONE,            /* drivers has completed the command */
292         BLK_EH_RESET_TIMER,     /* reset timer and try again */
293 };
294 
295 enum blk_queue_state {
296         Queue_down,
297         Queue_up,
298 };
299 
300 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
301 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
302 
303 #define BLK_SCSI_MAX_CMDS       (256)
304 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
305 
306 /*
307  * Zoned block device models (zoned limit).
308  */
309 enum blk_zoned_model {
310         BLK_ZONED_NONE, /* Regular block device */
311         BLK_ZONED_HA,   /* Host-aware zoned block device */
312         BLK_ZONED_HM,   /* Host-managed zoned block device */
313 };
314 
315 struct queue_limits {
316         unsigned long           bounce_pfn;
317         unsigned long           seg_boundary_mask;
318         unsigned long           virt_boundary_mask;
319 
320         unsigned int            max_hw_sectors;
321         unsigned int            max_dev_sectors;
322         unsigned int            chunk_sectors;
323         unsigned int            max_sectors;
324         unsigned int            max_segment_size;
325         unsigned int            physical_block_size;
326         unsigned int            alignment_offset;
327         unsigned int            io_min;
328         unsigned int            io_opt;
329         unsigned int            max_discard_sectors;
330         unsigned int            max_hw_discard_sectors;
331         unsigned int            max_write_same_sectors;
332         unsigned int            max_write_zeroes_sectors;
333         unsigned int            discard_granularity;
334         unsigned int            discard_alignment;
335 
336         unsigned short          logical_block_size;
337         unsigned short          max_segments;
338         unsigned short          max_integrity_segments;
339         unsigned short          max_discard_segments;
340 
341         unsigned char           misaligned;
342         unsigned char           discard_misaligned;
343         unsigned char           raid_partial_stripes_expensive;
344         enum blk_zoned_model    zoned;
345 };
346 
347 #ifdef CONFIG_BLK_DEV_ZONED
348 
349 extern unsigned int blkdev_nr_zones(struct block_device *bdev);
350 extern int blkdev_report_zones(struct block_device *bdev,
351                                sector_t sector, struct blk_zone *zones,
352                                unsigned int *nr_zones, gfp_t gfp_mask);
353 extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors,
354                               sector_t nr_sectors, gfp_t gfp_mask);
355 extern int blk_revalidate_disk_zones(struct gendisk *disk);
356 
357 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
358                                      unsigned int cmd, unsigned long arg);
359 extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
360                                     unsigned int cmd, unsigned long arg);
361 
362 #else /* CONFIG_BLK_DEV_ZONED */
363 
364 static inline unsigned int blkdev_nr_zones(struct block_device *bdev)
365 {
366         return 0;
367 }
368 
369 static inline int blk_revalidate_disk_zones(struct gendisk *disk)
370 {
371         return 0;
372 }
373 
374 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
375                                             fmode_t mode, unsigned int cmd,
376                                             unsigned long arg)
377 {
378         return -ENOTTY;
379 }
380 
381 static inline int blkdev_reset_zones_ioctl(struct block_device *bdev,
382                                            fmode_t mode, unsigned int cmd,
383                                            unsigned long arg)
384 {
385         return -ENOTTY;
386 }
387 
388 #endif /* CONFIG_BLK_DEV_ZONED */
389 
390 struct request_queue {
391         /*
392          * Together with queue_head for cacheline sharing
393          */
394         struct list_head        queue_head;
395         struct request          *last_merge;
396         struct elevator_queue   *elevator;
397 
398         struct blk_queue_stats  *stats;
399         struct rq_qos           *rq_qos;
400 
401         make_request_fn         *make_request_fn;
402         dma_drain_needed_fn     *dma_drain_needed;
403 
404         const struct blk_mq_ops *mq_ops;
405 
406         /* sw queues */
407         struct blk_mq_ctx __percpu      *queue_ctx;
408         unsigned int            nr_queues;
409 
410         unsigned int            queue_depth;
411 
412         /* hw dispatch queues */
413         struct blk_mq_hw_ctx    **queue_hw_ctx;
414         unsigned int            nr_hw_queues;
415 
416         struct backing_dev_info *backing_dev_info;
417 
418         /*
419          * The queue owner gets to use this for whatever they like.
420          * ll_rw_blk doesn't touch it.
421          */
422         void                    *queuedata;
423 
424         /*
425          * various queue flags, see QUEUE_* below
426          */
427         unsigned long           queue_flags;
428         /*
429          * Number of contexts that have called blk_set_pm_only(). If this
430          * counter is above zero then only RQF_PM and RQF_PREEMPT requests are
431          * processed.
432          */
433         atomic_t                pm_only;
434 
435         /*
436          * ida allocated id for this queue.  Used to index queues from
437          * ioctx.
438          */
439         int                     id;
440 
441         /*
442          * queue needs bounce pages for pages above this limit
443          */
444         gfp_t                   bounce_gfp;
445 
446         spinlock_t              queue_lock;
447 
448         /*
449          * queue kobject
450          */
451         struct kobject kobj;
452 
453         /*
454          * mq queue kobject
455          */
456         struct kobject *mq_kobj;
457 
458 #ifdef  CONFIG_BLK_DEV_INTEGRITY
459         struct blk_integrity integrity;
460 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
461 
462 #ifdef CONFIG_PM
463         struct device           *dev;
464         int                     rpm_status;
465         unsigned int            nr_pending;
466 #endif
467 
468         /*
469          * queue settings
470          */
471         unsigned long           nr_requests;    /* Max # of requests */
472 
473         unsigned int            dma_drain_size;
474         void                    *dma_drain_buffer;
475         unsigned int            dma_pad_mask;
476         unsigned int            dma_alignment;
477 
478         unsigned int            rq_timeout;
479         int                     poll_nsec;
480 
481         struct blk_stat_callback        *poll_cb;
482         struct blk_rq_stat      poll_stat[BLK_MQ_POLL_STATS_BKTS];
483 
484         struct timer_list       timeout;
485         struct work_struct      timeout_work;
486 
487         struct list_head        icq_list;
488 #ifdef CONFIG_BLK_CGROUP
489         DECLARE_BITMAP          (blkcg_pols, BLKCG_MAX_POLS);
490         struct blkcg_gq         *root_blkg;
491         struct list_head        blkg_list;
492 #endif
493 
494         struct queue_limits     limits;
495 
496 #ifdef CONFIG_BLK_DEV_ZONED
497         /*
498          * Zoned block device information for request dispatch control.
499          * nr_zones is the total number of zones of the device. This is always
500          * 0 for regular block devices. seq_zones_bitmap is a bitmap of nr_zones
501          * bits which indicates if a zone is conventional (bit clear) or
502          * sequential (bit set). seq_zones_wlock is a bitmap of nr_zones
503          * bits which indicates if a zone is write locked, that is, if a write
504          * request targeting the zone was dispatched. All three fields are
505          * initialized by the low level device driver (e.g. scsi/sd.c).
506          * Stacking drivers (device mappers) may or may not initialize
507          * these fields.
508          *
509          * Reads of this information must be protected with blk_queue_enter() /
510          * blk_queue_exit(). Modifying this information is only allowed while
511          * no requests are being processed. See also blk_mq_freeze_queue() and
512          * blk_mq_unfreeze_queue().
513          */
514         unsigned int            nr_zones;
515         unsigned long           *seq_zones_bitmap;
516         unsigned long           *seq_zones_wlock;
517 #endif /* CONFIG_BLK_DEV_ZONED */
518 
519         /*
520          * sg stuff
521          */
522         unsigned int            sg_timeout;
523         unsigned int            sg_reserved_size;
524         int                     node;
525 #ifdef CONFIG_BLK_DEV_IO_TRACE
526         struct blk_trace        *blk_trace;
527         struct mutex            blk_trace_mutex;
528 #endif
529         /*
530          * for flush operations
531          */
532         struct blk_flush_queue  *fq;
533 
534         struct list_head        requeue_list;
535         spinlock_t              requeue_lock;
536         struct delayed_work     requeue_work;
537 
538         struct mutex            sysfs_lock;
539 
540         atomic_t                mq_freeze_depth;
541 
542 #if defined(CONFIG_BLK_DEV_BSG)
543         struct bsg_class_device bsg_dev;
544 #endif
545 
546 #ifdef CONFIG_BLK_DEV_THROTTLING
547         /* Throttle data */
548         struct throtl_data *td;
549 #endif
550         struct rcu_head         rcu_head;
551         wait_queue_head_t       mq_freeze_wq;
552         struct percpu_ref       q_usage_counter;
553         struct list_head        all_q_node;
554 
555         struct blk_mq_tag_set   *tag_set;
556         struct list_head        tag_set_list;
557         struct bio_set          bio_split;
558 
559 #ifdef CONFIG_BLK_DEBUG_FS
560         struct dentry           *debugfs_dir;
561         struct dentry           *sched_debugfs_dir;
562         struct dentry           *rqos_debugfs_dir;
563 #endif
564 
565         bool                    mq_sysfs_init_done;
566 
567         size_t                  cmd_size;
568 
569         struct work_struct      release_work;
570 
571 #define BLK_MAX_WRITE_HINTS     5
572         u64                     write_hints[BLK_MAX_WRITE_HINTS];
573 };
574 
575 #define QUEUE_FLAG_STOPPED      1       /* queue is stopped */
576 #define QUEUE_FLAG_DYING        2       /* queue being torn down */
577 #define QUEUE_FLAG_BIDI         4       /* queue supports bidi requests */
578 #define QUEUE_FLAG_NOMERGES     5       /* disable merge attempts */
579 #define QUEUE_FLAG_SAME_COMP    6       /* complete on same CPU-group */
580 #define QUEUE_FLAG_FAIL_IO      7       /* fake timeout */
581 #define QUEUE_FLAG_NONROT       9       /* non-rotational device (SSD) */
582 #define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
583 #define QUEUE_FLAG_IO_STAT     10       /* do disk/partitions IO accounting */
584 #define QUEUE_FLAG_DISCARD     11       /* supports DISCARD */
585 #define QUEUE_FLAG_NOXMERGES   12       /* No extended merges */
586 #define QUEUE_FLAG_ADD_RANDOM  13       /* Contributes to random pool */
587 #define QUEUE_FLAG_SECERASE    14       /* supports secure erase */
588 #define QUEUE_FLAG_SAME_FORCE  15       /* force complete on same CPU */
589 #define QUEUE_FLAG_DEAD        16       /* queue tear-down finished */
590 #define QUEUE_FLAG_INIT_DONE   17       /* queue is initialized */
591 #define QUEUE_FLAG_NO_SG_MERGE 18       /* don't attempt to merge SG segments*/
592 #define QUEUE_FLAG_POLL        19       /* IO polling enabled if set */
593 #define QUEUE_FLAG_WC          20       /* Write back caching */
594 #define QUEUE_FLAG_FUA         21       /* device supports FUA writes */
595 #define QUEUE_FLAG_FLUSH_NQ    22       /* flush not queueuable */
596 #define QUEUE_FLAG_DAX         23       /* device supports DAX */
597 #define QUEUE_FLAG_STATS       24       /* track IO start and completion times */
598 #define QUEUE_FLAG_POLL_STATS  25       /* collecting stats for hybrid polling */
599 #define QUEUE_FLAG_REGISTERED  26       /* queue has been registered to a disk */
600 #define QUEUE_FLAG_SCSI_PASSTHROUGH 27  /* queue supports SCSI commands */
601 #define QUEUE_FLAG_QUIESCED    28       /* queue has been quiesced */
602 #define QUEUE_FLAG_PCI_P2PDMA  29       /* device supports PCI p2p requests */
603 
604 #define QUEUE_FLAG_DEFAULT      ((1 << QUEUE_FLAG_IO_STAT) |            \
605                                  (1 << QUEUE_FLAG_SAME_COMP)    |       \
606                                  (1 << QUEUE_FLAG_ADD_RANDOM))
607 
608 #define QUEUE_FLAG_MQ_DEFAULT   ((1 << QUEUE_FLAG_IO_STAT) |            \
609                                  (1 << QUEUE_FLAG_SAME_COMP))
610 
611 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
612 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
613 bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
614 
615 #define blk_queue_stopped(q)    test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
616 #define blk_queue_dying(q)      test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
617 #define blk_queue_dead(q)       test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
618 #define blk_queue_init_done(q)  test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
619 #define blk_queue_nomerges(q)   test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
620 #define blk_queue_noxmerges(q)  \
621         test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
622 #define blk_queue_nonrot(q)     test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
623 #define blk_queue_io_stat(q)    test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
624 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
625 #define blk_queue_discard(q)    test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
626 #define blk_queue_secure_erase(q) \
627         (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
628 #define blk_queue_dax(q)        test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
629 #define blk_queue_scsi_passthrough(q)   \
630         test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
631 #define blk_queue_pci_p2pdma(q) \
632         test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
633 
634 #define blk_noretry_request(rq) \
635         ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
636                              REQ_FAILFAST_DRIVER))
637 #define blk_queue_quiesced(q)   test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
638 #define blk_queue_pm_only(q)    atomic_read(&(q)->pm_only)
639 #define blk_queue_fua(q)        test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
640 
641 extern void blk_set_pm_only(struct request_queue *q);
642 extern void blk_clear_pm_only(struct request_queue *q);
643 
644 static inline bool blk_account_rq(struct request *rq)
645 {
646         return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
647 }
648 
649 #define blk_bidi_rq(rq)         ((rq)->next_rq != NULL)
650 
651 #define list_entry_rq(ptr)      list_entry((ptr), struct request, queuelist)
652 
653 #define rq_data_dir(rq)         (op_is_write(req_op(rq)) ? WRITE : READ)
654 
655 static inline bool queue_is_mq(struct request_queue *q)
656 {
657         return q->mq_ops;
658 }
659 
660 static inline enum blk_zoned_model
661 blk_queue_zoned_model(struct request_queue *q)
662 {
663         return q->limits.zoned;
664 }
665 
666 static inline bool blk_queue_is_zoned(struct request_queue *q)
667 {
668         switch (blk_queue_zoned_model(q)) {
669         case BLK_ZONED_HA:
670         case BLK_ZONED_HM:
671                 return true;
672         default:
673                 return false;
674         }
675 }
676 
677 static inline unsigned int blk_queue_zone_sectors(struct request_queue *q)
678 {
679         return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
680 }
681 
682 #ifdef CONFIG_BLK_DEV_ZONED
683 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
684 {
685         return blk_queue_is_zoned(q) ? q->nr_zones : 0;
686 }
687 
688 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
689                                              sector_t sector)
690 {
691         if (!blk_queue_is_zoned(q))
692                 return 0;
693         return sector >> ilog2(q->limits.chunk_sectors);
694 }
695 
696 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
697                                          sector_t sector)
698 {
699         if (!blk_queue_is_zoned(q) || !q->seq_zones_bitmap)
700                 return false;
701         return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap);
702 }
703 #else /* CONFIG_BLK_DEV_ZONED */
704 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
705 {
706         return 0;
707 }
708 #endif /* CONFIG_BLK_DEV_ZONED */
709 
710 static inline bool rq_is_sync(struct request *rq)
711 {
712         return op_is_sync(rq->cmd_flags);
713 }
714 
715 static inline bool rq_mergeable(struct request *rq)
716 {
717         if (blk_rq_is_passthrough(rq))
718                 return false;
719 
720         if (req_op(rq) == REQ_OP_FLUSH)
721                 return false;
722 
723         if (req_op(rq) == REQ_OP_WRITE_ZEROES)
724                 return false;
725 
726         if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
727                 return false;
728         if (rq->rq_flags & RQF_NOMERGE_FLAGS)
729                 return false;
730 
731         return true;
732 }
733 
734 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
735 {
736         if (bio_page(a) == bio_page(b) &&
737             bio_offset(a) == bio_offset(b))
738                 return true;
739 
740         return false;
741 }
742 
743 static inline unsigned int blk_queue_depth(struct request_queue *q)
744 {
745         if (q->queue_depth)
746                 return q->queue_depth;
747 
748         return q->nr_requests;
749 }
750 
751 extern unsigned long blk_max_low_pfn, blk_max_pfn;
752 
753 /*
754  * standard bounce addresses:
755  *
756  * BLK_BOUNCE_HIGH      : bounce all highmem pages
757  * BLK_BOUNCE_ANY       : don't bounce anything
758  * BLK_BOUNCE_ISA       : bounce pages above ISA DMA boundary
759  */
760 
761 #if BITS_PER_LONG == 32
762 #define BLK_BOUNCE_HIGH         ((u64)blk_max_low_pfn << PAGE_SHIFT)
763 #else
764 #define BLK_BOUNCE_HIGH         -1ULL
765 #endif
766 #define BLK_BOUNCE_ANY          (-1ULL)
767 #define BLK_BOUNCE_ISA          (DMA_BIT_MASK(24))
768 
769 /*
770  * default timeout for SG_IO if none specified
771  */
772 #define BLK_DEFAULT_SG_TIMEOUT  (60 * HZ)
773 #define BLK_MIN_SG_TIMEOUT      (7 * HZ)
774 
775 struct rq_map_data {
776         struct page **pages;
777         int page_order;
778         int nr_entries;
779         unsigned long offset;
780         int null_mapped;
781         int from_user;
782 };
783 
784 struct req_iterator {
785         struct bvec_iter iter;
786         struct bio *bio;
787 };
788 
789 /* This should not be used directly - use rq_for_each_segment */
790 #define for_each_bio(_bio)              \
791         for (; _bio; _bio = _bio->bi_next)
792 #define __rq_for_each_bio(_bio, rq)     \
793         if ((rq->bio))                  \
794                 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
795 
796 #define rq_for_each_segment(bvl, _rq, _iter)                    \
797         __rq_for_each_bio(_iter.bio, _rq)                       \
798                 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
799 
800 #define rq_iter_last(bvec, _iter)                               \
801                 (_iter.bio->bi_next == NULL &&                  \
802                  bio_iter_last(bvec, _iter.iter))
803 
804 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
805 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
806 #endif
807 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
808 extern void rq_flush_dcache_pages(struct request *rq);
809 #else
810 static inline void rq_flush_dcache_pages(struct request *rq)
811 {
812 }
813 #endif
814 
815 extern int blk_register_queue(struct gendisk *disk);
816 extern void blk_unregister_queue(struct gendisk *disk);
817 extern blk_qc_t generic_make_request(struct bio *bio);
818 extern blk_qc_t direct_make_request(struct bio *bio);
819 extern void blk_rq_init(struct request_queue *q, struct request *rq);
820 extern void blk_init_request_from_bio(struct request *req, struct bio *bio);
821 extern void blk_put_request(struct request *);
822 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
823                                        blk_mq_req_flags_t flags);
824 extern int blk_lld_busy(struct request_queue *q);
825 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
826                              struct bio_set *bs, gfp_t gfp_mask,
827                              int (*bio_ctr)(struct bio *, struct bio *, void *),
828                              void *data);
829 extern void blk_rq_unprep_clone(struct request *rq);
830 extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
831                                      struct request *rq);
832 extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
833 extern void blk_queue_split(struct request_queue *, struct bio **);
834 extern void blk_recount_segments(struct request_queue *, struct bio *);
835 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
836 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
837                               unsigned int, void __user *);
838 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
839                           unsigned int, void __user *);
840 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
841                          struct scsi_ioctl_command __user *);
842 
843 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
844 extern void blk_queue_exit(struct request_queue *q);
845 extern void blk_sync_queue(struct request_queue *q);
846 extern int blk_rq_map_user(struct request_queue *, struct request *,
847                            struct rq_map_data *, void __user *, unsigned long,
848                            gfp_t);
849 extern int blk_rq_unmap_user(struct bio *);
850 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
851 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
852                                struct rq_map_data *, const struct iov_iter *,
853                                gfp_t);
854 extern void blk_execute_rq(struct request_queue *, struct gendisk *,
855                           struct request *, int);
856 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
857                                   struct request *, int, rq_end_io_fn *);
858 
859 int blk_status_to_errno(blk_status_t status);
860 blk_status_t errno_to_blk_status(int errno);
861 
862 int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin);
863 
864 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
865 {
866         return bdev->bd_disk->queue;    /* this is never NULL */
867 }
868 
869 /*
870  * The basic unit of block I/O is a sector. It is used in a number of contexts
871  * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
872  * bytes. Variables of type sector_t represent an offset or size that is a
873  * multiple of 512 bytes. Hence these two constants.
874  */
875 #ifndef SECTOR_SHIFT
876 #define SECTOR_SHIFT 9
877 #endif
878 #ifndef SECTOR_SIZE
879 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
880 #endif
881 
882 /*
883  * blk_rq_pos()                 : the current sector
884  * blk_rq_bytes()               : bytes left in the entire request
885  * blk_rq_cur_bytes()           : bytes left in the current segment
886  * blk_rq_err_bytes()           : bytes left till the next error boundary
887  * blk_rq_sectors()             : sectors left in the entire request
888  * blk_rq_cur_sectors()         : sectors left in the current segment
889  */
890 static inline sector_t blk_rq_pos(const struct request *rq)
891 {
892         return rq->__sector;
893 }
894 
895 static inline unsigned int blk_rq_bytes(const struct request *rq)
896 {
897         return rq->__data_len;
898 }
899 
900 static inline int blk_rq_cur_bytes(const struct request *rq)
901 {
902         return rq->bio ? bio_cur_bytes(rq->bio) : 0;
903 }
904 
905 extern unsigned int blk_rq_err_bytes(const struct request *rq);
906 
907 static inline unsigned int blk_rq_sectors(const struct request *rq)
908 {
909         return blk_rq_bytes(rq) >> SECTOR_SHIFT;
910 }
911 
912 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
913 {
914         return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
915 }
916 
917 #ifdef CONFIG_BLK_DEV_ZONED
918 static inline unsigned int blk_rq_zone_no(struct request *rq)
919 {
920         return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
921 }
922 
923 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
924 {
925         return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
926 }
927 #endif /* CONFIG_BLK_DEV_ZONED */
928 
929 /*
930  * Some commands like WRITE SAME have a payload or data transfer size which
931  * is different from the size of the request.  Any driver that supports such
932  * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
933  * calculate the data transfer size.
934  */
935 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
936 {
937         if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
938                 return rq->special_vec.bv_len;
939         return blk_rq_bytes(rq);
940 }
941 
942 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
943                                                      int op)
944 {
945         if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
946                 return min(q->limits.max_discard_sectors,
947                            UINT_MAX >> SECTOR_SHIFT);
948 
949         if (unlikely(op == REQ_OP_WRITE_SAME))
950                 return q->limits.max_write_same_sectors;
951 
952         if (unlikely(op == REQ_OP_WRITE_ZEROES))
953                 return q->limits.max_write_zeroes_sectors;
954 
955         return q->limits.max_sectors;
956 }
957 
958 /*
959  * Return maximum size of a request at given offset. Only valid for
960  * file system requests.
961  */
962 static inline unsigned int blk_max_size_offset(struct request_queue *q,
963                                                sector_t offset)
964 {
965         if (!q->limits.chunk_sectors)
966                 return q->limits.max_sectors;
967 
968         return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
969                         (offset & (q->limits.chunk_sectors - 1))));
970 }
971 
972 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
973                                                   sector_t offset)
974 {
975         struct request_queue *q = rq->q;
976 
977         if (blk_rq_is_passthrough(rq))
978                 return q->limits.max_hw_sectors;
979 
980         if (!q->limits.chunk_sectors ||
981             req_op(rq) == REQ_OP_DISCARD ||
982             req_op(rq) == REQ_OP_SECURE_ERASE)
983                 return blk_queue_get_max_sectors(q, req_op(rq));
984 
985         return min(blk_max_size_offset(q, offset),
986                         blk_queue_get_max_sectors(q, req_op(rq)));
987 }
988 
989 static inline unsigned int blk_rq_count_bios(struct request *rq)
990 {
991         unsigned int nr_bios = 0;
992         struct bio *bio;
993 
994         __rq_for_each_bio(bio, rq)
995                 nr_bios++;
996 
997         return nr_bios;
998 }
999 
1000 void blk_steal_bios(struct bio_list *list, struct request *rq);
1001 
1002 /*
1003  * Request completion related functions.
1004  *
1005  * blk_update_request() completes given number of bytes and updates
1006  * the request without completing it.
1007  *
1008  * blk_end_request() and friends.  __blk_end_request() must be called
1009  * with the request queue spinlock acquired.
1010  *
1011  * Several drivers define their own end_request and call
1012  * blk_end_request() for parts of the original function.
1013  * This prevents code duplication in drivers.
1014  */
1015 extern bool blk_update_request(struct request *rq, blk_status_t error,
1016                                unsigned int nr_bytes);
1017 extern void blk_end_request_all(struct request *rq, blk_status_t error);
1018 extern bool __blk_end_request(struct request *rq, blk_status_t error,
1019                               unsigned int nr_bytes);
1020 extern void __blk_end_request_all(struct request *rq, blk_status_t error);
1021 extern bool __blk_end_request_cur(struct request *rq, blk_status_t error);
1022 
1023 extern void __blk_complete_request(struct request *);
1024 extern void blk_abort_request(struct request *);
1025 
1026 /*
1027  * Access functions for manipulating queue properties
1028  */
1029 extern void blk_cleanup_queue(struct request_queue *);
1030 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1031 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1032 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1033 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1034 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1035 extern void blk_queue_max_discard_segments(struct request_queue *,
1036                 unsigned short);
1037 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1038 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1039                 unsigned int max_discard_sectors);
1040 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1041                 unsigned int max_write_same_sectors);
1042 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1043                 unsigned int max_write_same_sectors);
1044 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1045 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1046 extern void blk_queue_alignment_offset(struct request_queue *q,
1047                                        unsigned int alignment);
1048 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1049 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1050 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1051 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1052 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1053 extern void blk_set_default_limits(struct queue_limits *lim);
1054 extern void blk_set_stacking_limits(struct queue_limits *lim);
1055 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1056                             sector_t offset);
1057 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1058                             sector_t offset);
1059 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1060                               sector_t offset);
1061 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1062 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1063 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1064 extern int blk_queue_dma_drain(struct request_queue *q,
1065                                dma_drain_needed_fn *dma_drain_needed,
1066                                void *buf, unsigned int size);
1067 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1068 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1069 extern void blk_queue_dma_alignment(struct request_queue *, int);
1070 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1071 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1072 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1073 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1074 
1075 /*
1076  * Number of physical segments as sent to the device.
1077  *
1078  * Normally this is the number of discontiguous data segments sent by the
1079  * submitter.  But for data-less command like discard we might have no
1080  * actual data segments submitted, but the driver might have to add it's
1081  * own special payload.  In that case we still return 1 here so that this
1082  * special payload will be mapped.
1083  */
1084 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1085 {
1086         if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1087                 return 1;
1088         return rq->nr_phys_segments;
1089 }
1090 
1091 /*
1092  * Number of discard segments (or ranges) the driver needs to fill in.
1093  * Each discard bio merged into a request is counted as one segment.
1094  */
1095 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1096 {
1097         return max_t(unsigned short, rq->nr_phys_segments, 1);
1098 }
1099 
1100 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1101 extern void blk_dump_rq_flags(struct request *, char *);
1102 extern long nr_blockdev_pages(void);
1103 
1104 bool __must_check blk_get_queue(struct request_queue *);
1105 struct request_queue *blk_alloc_queue(gfp_t);
1106 struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id);
1107 extern void blk_put_queue(struct request_queue *);
1108 extern void blk_set_queue_dying(struct request_queue *);
1109 
1110 /*
1111  * blk_plug permits building a queue of related requests by holding the I/O
1112  * fragments for a short period. This allows merging of sequential requests
1113  * into single larger request. As the requests are moved from a per-task list to
1114  * the device's request_queue in a batch, this results in improved scalability
1115  * as the lock contention for request_queue lock is reduced.
1116  *
1117  * It is ok not to disable preemption when adding the request to the plug list
1118  * or when attempting a merge, because blk_schedule_flush_list() will only flush
1119  * the plug list when the task sleeps by itself. For details, please see
1120  * schedule() where blk_schedule_flush_plug() is called.
1121  */
1122 struct blk_plug {
1123         struct list_head mq_list; /* blk-mq requests */
1124         struct list_head cb_list; /* md requires an unplug callback */
1125         unsigned short rq_count;
1126         bool multiple_queues;
1127 };
1128 #define BLK_MAX_REQUEST_COUNT 16
1129 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1130 
1131 struct blk_plug_cb;
1132 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1133 struct blk_plug_cb {
1134         struct list_head list;
1135         blk_plug_cb_fn callback;
1136         void *data;
1137 };
1138 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1139                                              void *data, int size);
1140 extern void blk_start_plug(struct blk_plug *);
1141 extern void blk_finish_plug(struct blk_plug *);
1142 extern void blk_flush_plug_list(struct blk_plug *, bool);
1143 
1144 static inline void blk_flush_plug(struct task_struct *tsk)
1145 {
1146         struct blk_plug *plug = tsk->plug;
1147 
1148         if (plug)
1149                 blk_flush_plug_list(plug, false);
1150 }
1151 
1152 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1153 {
1154         struct blk_plug *plug = tsk->plug;
1155 
1156         if (plug)
1157                 blk_flush_plug_list(plug, true);
1158 }
1159 
1160 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1161 {
1162         struct blk_plug *plug = tsk->plug;
1163 
1164         return plug &&
1165                  (!list_empty(&plug->mq_list) ||
1166                  !list_empty(&plug->cb_list));
1167 }
1168 
1169 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1170 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1171                 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1172 
1173 #define BLKDEV_DISCARD_SECURE   (1 << 0)        /* issue a secure erase */
1174 
1175 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1176                 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1177 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1178                 sector_t nr_sects, gfp_t gfp_mask, int flags,
1179                 struct bio **biop);
1180 
1181 #define BLKDEV_ZERO_NOUNMAP     (1 << 0)  /* do not free blocks */
1182 #define BLKDEV_ZERO_NOFALLBACK  (1 << 1)  /* don't write explicit zeroes */
1183 
1184 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1185                 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1186                 unsigned flags);
1187 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1188                 sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1189 
1190 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1191                 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1192 {
1193         return blkdev_issue_discard(sb->s_bdev,
1194                                     block << (sb->s_blocksize_bits -
1195                                               SECTOR_SHIFT),
1196                                     nr_blocks << (sb->s_blocksize_bits -
1197                                                   SECTOR_SHIFT),
1198                                     gfp_mask, flags);
1199 }
1200 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1201                 sector_t nr_blocks, gfp_t gfp_mask)
1202 {
1203         return blkdev_issue_zeroout(sb->s_bdev,
1204                                     block << (sb->s_blocksize_bits -
1205                                               SECTOR_SHIFT),
1206                                     nr_blocks << (sb->s_blocksize_bits -
1207                                                   SECTOR_SHIFT),
1208                                     gfp_mask, 0);
1209 }
1210 
1211 extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1212 
1213 enum blk_default_limits {
1214         BLK_MAX_SEGMENTS        = 128,
1215         BLK_SAFE_MAX_SECTORS    = 255,
1216         BLK_DEF_MAX_SECTORS     = 2560,
1217         BLK_MAX_SEGMENT_SIZE    = 65536,
1218         BLK_SEG_BOUNDARY_MASK   = 0xFFFFFFFFUL,
1219 };
1220 
1221 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1222 {
1223         return q->limits.seg_boundary_mask;
1224 }
1225 
1226 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1227 {
1228         return q->limits.virt_boundary_mask;
1229 }
1230 
1231 static inline unsigned int queue_max_sectors(struct request_queue *q)
1232 {
1233         return q->limits.max_sectors;
1234 }
1235 
1236 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1237 {
1238         return q->limits.max_hw_sectors;
1239 }
1240 
1241 static inline unsigned short queue_max_segments(struct request_queue *q)
1242 {
1243         return q->limits.max_segments;
1244 }
1245 
1246 static inline unsigned short queue_max_discard_segments(struct request_queue *q)
1247 {
1248         return q->limits.max_discard_segments;
1249 }
1250 
1251 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1252 {
1253         return q->limits.max_segment_size;
1254 }
1255 
1256 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1257 {
1258         int retval = 512;
1259 
1260         if (q && q->limits.logical_block_size)
1261                 retval = q->limits.logical_block_size;
1262 
1263         return retval;
1264 }
1265 
1266 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1267 {
1268         return queue_logical_block_size(bdev_get_queue(bdev));
1269 }
1270 
1271 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1272 {
1273         return q->limits.physical_block_size;
1274 }
1275 
1276 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1277 {
1278         return queue_physical_block_size(bdev_get_queue(bdev));
1279 }
1280 
1281 static inline unsigned int queue_io_min(struct request_queue *q)
1282 {
1283         return q->limits.io_min;
1284 }
1285 
1286 static inline int bdev_io_min(struct block_device *bdev)
1287 {
1288         return queue_io_min(bdev_get_queue(bdev));
1289 }
1290 
1291 static inline unsigned int queue_io_opt(struct request_queue *q)
1292 {
1293         return q->limits.io_opt;
1294 }
1295 
1296 static inline int bdev_io_opt(struct block_device *bdev)
1297 {
1298         return queue_io_opt(bdev_get_queue(bdev));
1299 }
1300 
1301 static inline int queue_alignment_offset(struct request_queue *q)
1302 {
1303         if (q->limits.misaligned)
1304                 return -1;
1305 
1306         return q->limits.alignment_offset;
1307 }
1308 
1309 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1310 {
1311         unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1312         unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1313                 << SECTOR_SHIFT;
1314 
1315         return (granularity + lim->alignment_offset - alignment) % granularity;
1316 }
1317 
1318 static inline int bdev_alignment_offset(struct block_device *bdev)
1319 {
1320         struct request_queue *q = bdev_get_queue(bdev);
1321 
1322         if (q->limits.misaligned)
1323                 return -1;
1324 
1325         if (bdev != bdev->bd_contains)
1326                 return bdev->bd_part->alignment_offset;
1327 
1328         return q->limits.alignment_offset;
1329 }
1330 
1331 static inline int queue_discard_alignment(struct request_queue *q)
1332 {
1333         if (q->limits.discard_misaligned)
1334                 return -1;
1335 
1336         return q->limits.discard_alignment;
1337 }
1338 
1339 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1340 {
1341         unsigned int alignment, granularity, offset;
1342 
1343         if (!lim->max_discard_sectors)
1344                 return 0;
1345 
1346         /* Why are these in bytes, not sectors? */
1347         alignment = lim->discard_alignment >> SECTOR_SHIFT;
1348         granularity = lim->discard_granularity >> SECTOR_SHIFT;
1349         if (!granularity)
1350                 return 0;
1351 
1352         /* Offset of the partition start in 'granularity' sectors */
1353         offset = sector_div(sector, granularity);
1354 
1355         /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1356         offset = (granularity + alignment - offset) % granularity;
1357 
1358         /* Turn it back into bytes, gaah */
1359         return offset << SECTOR_SHIFT;
1360 }
1361 
1362 static inline int bdev_discard_alignment(struct block_device *bdev)
1363 {
1364         struct request_queue *q = bdev_get_queue(bdev);
1365 
1366         if (bdev != bdev->bd_contains)
1367                 return bdev->bd_part->discard_alignment;
1368 
1369         return q->limits.discard_alignment;
1370 }
1371 
1372 static inline unsigned int bdev_write_same(struct block_device *bdev)
1373 {
1374         struct request_queue *q = bdev_get_queue(bdev);
1375 
1376         if (q)
1377                 return q->limits.max_write_same_sectors;
1378 
1379         return 0;
1380 }
1381 
1382 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1383 {
1384         struct request_queue *q = bdev_get_queue(bdev);
1385 
1386         if (q)
1387                 return q->limits.max_write_zeroes_sectors;
1388 
1389         return 0;
1390 }
1391 
1392 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1393 {
1394         struct request_queue *q = bdev_get_queue(bdev);
1395 
1396         if (q)
1397                 return blk_queue_zoned_model(q);
1398 
1399         return BLK_ZONED_NONE;
1400 }
1401 
1402 static inline bool bdev_is_zoned(struct block_device *bdev)
1403 {
1404         struct request_queue *q = bdev_get_queue(bdev);
1405 
1406         if (q)
1407                 return blk_queue_is_zoned(q);
1408 
1409         return false;
1410 }
1411 
1412 static inline unsigned int bdev_zone_sectors(struct block_device *bdev)
1413 {
1414         struct request_queue *q = bdev_get_queue(bdev);
1415 
1416         if (q)
1417                 return blk_queue_zone_sectors(q);
1418         return 0;
1419 }
1420 
1421 static inline int queue_dma_alignment(struct request_queue *q)
1422 {
1423         return q ? q->dma_alignment : 511;
1424 }
1425 
1426 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1427                                  unsigned int len)
1428 {
1429         unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1430         return !(addr & alignment) && !(len & alignment);
1431 }
1432 
1433 /* assumes size > 256 */
1434 static inline unsigned int blksize_bits(unsigned int size)
1435 {
1436         unsigned int bits = 8;
1437         do {
1438                 bits++;
1439                 size >>= 1;
1440         } while (size > 256);
1441         return bits;
1442 }
1443 
1444 static inline unsigned int block_size(struct block_device *bdev)
1445 {
1446         return bdev->bd_block_size;
1447 }
1448 
1449 static inline bool queue_flush_queueable(struct request_queue *q)
1450 {
1451         return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1452 }
1453 
1454 typedef struct {struct page *v;} Sector;
1455 
1456 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1457 
1458 static inline void put_dev_sector(Sector p)
1459 {
1460         put_page(p.v);
1461 }
1462 
1463 int kblockd_schedule_work(struct work_struct *work);
1464 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
1465 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1466 
1467 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1468         MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1469 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1470         MODULE_ALIAS("block-major-" __stringify(major) "-*")
1471 
1472 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1473 
1474 enum blk_integrity_flags {
1475         BLK_INTEGRITY_VERIFY            = 1 << 0,
1476         BLK_INTEGRITY_GENERATE          = 1 << 1,
1477         BLK_INTEGRITY_DEVICE_CAPABLE    = 1 << 2,
1478         BLK_INTEGRITY_IP_CHECKSUM       = 1 << 3,
1479 };
1480 
1481 struct blk_integrity_iter {
1482         void                    *prot_buf;
1483         void                    *data_buf;
1484         sector_t                seed;
1485         unsigned int            data_size;
1486         unsigned short          interval;
1487         const char              *disk_name;
1488 };
1489 
1490 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1491 
1492 struct blk_integrity_profile {
1493         integrity_processing_fn         *generate_fn;
1494         integrity_processing_fn         *verify_fn;
1495         const char                      *name;
1496 };
1497 
1498 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1499 extern void blk_integrity_unregister(struct gendisk *);
1500 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1501 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1502                                    struct scatterlist *);
1503 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1504 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1505                                    struct request *);
1506 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1507                                     struct bio *);
1508 
1509 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1510 {
1511         struct blk_integrity *bi = &disk->queue->integrity;
1512 
1513         if (!bi->profile)
1514                 return NULL;
1515 
1516         return bi;
1517 }
1518 
1519 static inline
1520 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1521 {
1522         return blk_get_integrity(bdev->bd_disk);
1523 }
1524 
1525 static inline bool blk_integrity_rq(struct request *rq)
1526 {
1527         return rq->cmd_flags & REQ_INTEGRITY;
1528 }
1529 
1530 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1531                                                     unsigned int segs)
1532 {
1533         q->limits.max_integrity_segments = segs;
1534 }
1535 
1536 static inline unsigned short
1537 queue_max_integrity_segments(struct request_queue *q)
1538 {
1539         return q->limits.max_integrity_segments;
1540 }
1541 
1542 /**
1543  * bio_integrity_intervals - Return number of integrity intervals for a bio
1544  * @bi:         blk_integrity profile for device
1545  * @sectors:    Size of the bio in 512-byte sectors
1546  *
1547  * Description: The block layer calculates everything in 512 byte
1548  * sectors but integrity metadata is done in terms of the data integrity
1549  * interval size of the storage device.  Convert the block layer sectors
1550  * to the appropriate number of integrity intervals.
1551  */
1552 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1553                                                    unsigned int sectors)
1554 {
1555         return sectors >> (bi->interval_exp - 9);
1556 }
1557 
1558 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1559                                                unsigned int sectors)
1560 {
1561         return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1562 }
1563 
1564 #else /* CONFIG_BLK_DEV_INTEGRITY */
1565 
1566 struct bio;
1567 struct block_device;
1568 struct gendisk;
1569 struct blk_integrity;
1570 
1571 static inline int blk_integrity_rq(struct request *rq)
1572 {
1573         return 0;
1574 }
1575 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1576                                             struct bio *b)
1577 {
1578         return 0;
1579 }
1580 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1581                                           struct bio *b,
1582                                           struct scatterlist *s)
1583 {
1584         return 0;
1585 }
1586 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1587 {
1588         return NULL;
1589 }
1590 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1591 {
1592         return NULL;
1593 }
1594 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1595 {
1596         return 0;
1597 }
1598 static inline void blk_integrity_register(struct gendisk *d,
1599                                          struct blk_integrity *b)
1600 {
1601 }
1602 static inline void blk_integrity_unregister(struct gendisk *d)
1603 {
1604 }
1605 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1606                                                     unsigned int segs)
1607 {
1608 }
1609 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1610 {
1611         return 0;
1612 }
1613 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1614                                           struct request *r1,
1615                                           struct request *r2)
1616 {
1617         return true;
1618 }
1619 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1620                                            struct request *r,
1621                                            struct bio *b)
1622 {
1623         return true;
1624 }
1625 
1626 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1627                                                    unsigned int sectors)
1628 {
1629         return 0;
1630 }
1631 
1632 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1633                                                unsigned int sectors)
1634 {
1635         return 0;
1636 }
1637 
1638 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1639 
1640 struct block_device_operations {
1641         int (*open) (struct block_device *, fmode_t);
1642         void (*release) (struct gendisk *, fmode_t);
1643         int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1644         int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1645         int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1646         unsigned int (*check_events) (struct gendisk *disk,
1647                                       unsigned int clearing);
1648         /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1649         int (*media_changed) (struct gendisk *);
1650         void (*unlock_native_capacity) (struct gendisk *);
1651         int (*revalidate_disk) (struct gendisk *);
1652         int (*getgeo)(struct block_device *, struct hd_geometry *);
1653         /* this callback is with swap_lock and sometimes page table lock held */
1654         void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1655         int (*report_zones)(struct gendisk *, sector_t sector,
1656                             struct blk_zone *zones, unsigned int *nr_zones,
1657                             gfp_t gfp_mask);
1658         struct module *owner;
1659         const struct pr_ops *pr_ops;
1660 };
1661 
1662 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1663                                  unsigned long);
1664 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1665 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1666                                                 struct writeback_control *);
1667 
1668 #ifdef CONFIG_BLK_DEV_ZONED
1669 bool blk_req_needs_zone_write_lock(struct request *rq);
1670 void __blk_req_zone_write_lock(struct request *rq);
1671 void __blk_req_zone_write_unlock(struct request *rq);
1672 
1673 static inline void blk_req_zone_write_lock(struct request *rq)
1674 {
1675         if (blk_req_needs_zone_write_lock(rq))
1676                 __blk_req_zone_write_lock(rq);
1677 }
1678 
1679 static inline void blk_req_zone_write_unlock(struct request *rq)
1680 {
1681         if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1682                 __blk_req_zone_write_unlock(rq);
1683 }
1684 
1685 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1686 {
1687         return rq->q->seq_zones_wlock &&
1688                 test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
1689 }
1690 
1691 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1692 {
1693         if (!blk_req_needs_zone_write_lock(rq))
1694                 return true;
1695         return !blk_req_zone_is_write_locked(rq);
1696 }
1697 #else
1698 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1699 {
1700         return false;
1701 }
1702 
1703 static inline void blk_req_zone_write_lock(struct request *rq)
1704 {
1705 }
1706 
1707 static inline void blk_req_zone_write_unlock(struct request *rq)
1708 {
1709 }
1710 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1711 {
1712         return false;
1713 }
1714 
1715 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1716 {
1717         return true;
1718 }
1719 #endif /* CONFIG_BLK_DEV_ZONED */
1720 
1721 #else /* CONFIG_BLOCK */
1722 
1723 struct block_device;
1724 
1725 /*
1726  * stubs for when the block layer is configured out
1727  */
1728 #define buffer_heads_over_limit 0
1729 
1730 static inline long nr_blockdev_pages(void)
1731 {
1732         return 0;
1733 }
1734 
1735 struct blk_plug {
1736 };
1737 
1738 static inline void blk_start_plug(struct blk_plug *plug)
1739 {
1740 }
1741 
1742 static inline void blk_finish_plug(struct blk_plug *plug)
1743 {
1744 }
1745 
1746 static inline void blk_flush_plug(struct task_struct *task)
1747 {
1748 }
1749 
1750 static inline void blk_schedule_flush_plug(struct task_struct *task)
1751 {
1752 }
1753 
1754 
1755 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1756 {
1757         return false;
1758 }
1759 
1760 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1761                                      sector_t *error_sector)
1762 {
1763         return 0;
1764 }
1765 
1766 #endif /* CONFIG_BLOCK */
1767 
1768 static inline void blk_wake_io_task(struct task_struct *waiter)
1769 {
1770         /*
1771          * If we're polling, the task itself is doing the completions. For
1772          * that case, we don't need to signal a wakeup, it's enough to just
1773          * mark us as RUNNING.
1774          */
1775         if (waiter == current)
1776                 __set_current_state(TASK_RUNNING);
1777         else
1778                 wake_up_process(waiter);
1779 }
1780 
1781 #endif
1782 

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