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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 /* Doing classic polling */
 54 #define BLK_MQ_POLL_CLASSIC -1
 55 
 56 /*
 57  * Maximum number of blkcg policies allowed to be registered concurrently.
 58  * Defined here to simplify include dependency.
 59  */
 60 #define BLKCG_MAX_POLS          5
 61 
 62 typedef void (rq_end_io_fn)(struct request *, blk_status_t);
 63 
 64 /*
 65  * request flags */
 66 typedef __u32 __bitwise req_flags_t;
 67 
 68 /* elevator knows about this request */
 69 #define RQF_SORTED              ((__force req_flags_t)(1 << 0))
 70 /* drive already may have started this one */
 71 #define RQF_STARTED             ((__force req_flags_t)(1 << 1))
 72 /* may not be passed by ioscheduler */
 73 #define RQF_SOFTBARRIER         ((__force req_flags_t)(1 << 3))
 74 /* request for flush sequence */
 75 #define RQF_FLUSH_SEQ           ((__force req_flags_t)(1 << 4))
 76 /* merge of different types, fail separately */
 77 #define RQF_MIXED_MERGE         ((__force req_flags_t)(1 << 5))
 78 /* track inflight for MQ */
 79 #define RQF_MQ_INFLIGHT         ((__force req_flags_t)(1 << 6))
 80 /* don't call prep for this one */
 81 #define RQF_DONTPREP            ((__force req_flags_t)(1 << 7))
 82 /* set for "ide_preempt" requests and also for requests for which the SCSI
 83    "quiesce" state must be ignored. */
 84 #define RQF_PREEMPT             ((__force req_flags_t)(1 << 8))
 85 /* contains copies of user pages */
 86 #define RQF_COPY_USER           ((__force req_flags_t)(1 << 9))
 87 /* vaguely specified driver internal error.  Ignored by the block layer */
 88 #define RQF_FAILED              ((__force req_flags_t)(1 << 10))
 89 /* don't warn about errors */
 90 #define RQF_QUIET               ((__force req_flags_t)(1 << 11))
 91 /* elevator private data attached */
 92 #define RQF_ELVPRIV             ((__force req_flags_t)(1 << 12))
 93 /* account into disk and partition IO statistics */
 94 #define RQF_IO_STAT             ((__force req_flags_t)(1 << 13))
 95 /* request came from our alloc pool */
 96 #define RQF_ALLOCED             ((__force req_flags_t)(1 << 14))
 97 /* runtime pm request */
 98 #define RQF_PM                  ((__force req_flags_t)(1 << 15))
 99 /* on IO scheduler merge hash */
100 #define RQF_HASHED              ((__force req_flags_t)(1 << 16))
101 /* track IO completion time */
102 #define RQF_STATS               ((__force req_flags_t)(1 << 17))
103 /* Look at ->special_vec for the actual data payload instead of the
104    bio chain. */
105 #define RQF_SPECIAL_PAYLOAD     ((__force req_flags_t)(1 << 18))
106 /* The per-zone write lock is held for this request */
107 #define RQF_ZONE_WRITE_LOCKED   ((__force req_flags_t)(1 << 19))
108 /* already slept for hybrid poll */
109 #define RQF_MQ_POLL_SLEPT       ((__force req_flags_t)(1 << 20))
110 /* ->timeout has been called, don't expire again */
111 #define RQF_TIMED_OUT           ((__force req_flags_t)(1 << 21))
112 
113 /* flags that prevent us from merging requests: */
114 #define RQF_NOMERGE_FLAGS \
115         (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
116 
117 /*
118  * Request state for blk-mq.
119  */
120 enum mq_rq_state {
121         MQ_RQ_IDLE              = 0,
122         MQ_RQ_IN_FLIGHT         = 1,
123         MQ_RQ_COMPLETE          = 2,
124 };
125 
126 /*
127  * Try to put the fields that are referenced together in the same cacheline.
128  *
129  * If you modify this structure, make sure to update blk_rq_init() and
130  * especially blk_mq_rq_ctx_init() to take care of the added fields.
131  */
132 struct request {
133         struct request_queue *q;
134         struct blk_mq_ctx *mq_ctx;
135         struct blk_mq_hw_ctx *mq_hctx;
136 
137         unsigned int cmd_flags;         /* op and common flags */
138         req_flags_t rq_flags;
139 
140         int tag;
141         int internal_tag;
142 
143         /* the following two fields are internal, NEVER access directly */
144         unsigned int __data_len;        /* total data len */
145         sector_t __sector;              /* sector cursor */
146 
147         struct bio *bio;
148         struct bio *biotail;
149 
150         struct list_head queuelist;
151 
152         /*
153          * The hash is used inside the scheduler, and killed once the
154          * request reaches the dispatch list. The ipi_list is only used
155          * to queue the request for softirq completion, which is long
156          * after the request has been unhashed (and even removed from
157          * the dispatch list).
158          */
159         union {
160                 struct hlist_node hash; /* merge hash */
161                 struct list_head ipi_list;
162         };
163 
164         /*
165          * The rb_node is only used inside the io scheduler, requests
166          * are pruned when moved to the dispatch queue. So let the
167          * completion_data share space with the rb_node.
168          */
169         union {
170                 struct rb_node rb_node; /* sort/lookup */
171                 struct bio_vec special_vec;
172                 void *completion_data;
173                 int error_count; /* for legacy drivers, don't use */
174         };
175 
176         /*
177          * Three pointers are available for the IO schedulers, if they need
178          * more they have to dynamically allocate it.  Flush requests are
179          * never put on the IO scheduler. So let the flush fields share
180          * space with the elevator data.
181          */
182         union {
183                 struct {
184                         struct io_cq            *icq;
185                         void                    *priv[2];
186                 } elv;
187 
188                 struct {
189                         unsigned int            seq;
190                         struct list_head        list;
191                         rq_end_io_fn            *saved_end_io;
192                 } flush;
193         };
194 
195         struct gendisk *rq_disk;
196         struct hd_struct *part;
197 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
198         /* Time that the first bio started allocating this request. */
199         u64 alloc_time_ns;
200 #endif
201         /* Time that this request was allocated for this IO. */
202         u64 start_time_ns;
203         /* Time that I/O was submitted to the device. */
204         u64 io_start_time_ns;
205 
206 #ifdef CONFIG_BLK_WBT
207         unsigned short wbt_flags;
208 #endif
209         /*
210          * rq sectors used for blk stats. It has the same value
211          * with blk_rq_sectors(rq), except that it never be zeroed
212          * by completion.
213          */
214         unsigned short stats_sectors;
215 
216         /*
217          * Number of scatter-gather DMA addr+len pairs after
218          * physical address coalescing is performed.
219          */
220         unsigned short nr_phys_segments;
221 
222 #if defined(CONFIG_BLK_DEV_INTEGRITY)
223         unsigned short nr_integrity_segments;
224 #endif
225 
226         unsigned short write_hint;
227         unsigned short ioprio;
228 
229         unsigned int extra_len; /* length of alignment and padding */
230 
231         enum mq_rq_state state;
232         refcount_t ref;
233 
234         unsigned int timeout;
235         unsigned long deadline;
236 
237         union {
238                 struct __call_single_data csd;
239                 u64 fifo_time;
240         };
241 
242         /*
243          * completion callback.
244          */
245         rq_end_io_fn *end_io;
246         void *end_io_data;
247 };
248 
249 static inline bool blk_op_is_scsi(unsigned int op)
250 {
251         return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
252 }
253 
254 static inline bool blk_op_is_private(unsigned int op)
255 {
256         return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
257 }
258 
259 static inline bool blk_rq_is_scsi(struct request *rq)
260 {
261         return blk_op_is_scsi(req_op(rq));
262 }
263 
264 static inline bool blk_rq_is_private(struct request *rq)
265 {
266         return blk_op_is_private(req_op(rq));
267 }
268 
269 static inline bool blk_rq_is_passthrough(struct request *rq)
270 {
271         return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
272 }
273 
274 static inline bool bio_is_passthrough(struct bio *bio)
275 {
276         unsigned op = bio_op(bio);
277 
278         return blk_op_is_scsi(op) || blk_op_is_private(op);
279 }
280 
281 static inline unsigned short req_get_ioprio(struct request *req)
282 {
283         return req->ioprio;
284 }
285 
286 #include <linux/elevator.h>
287 
288 struct blk_queue_ctx;
289 
290 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
291 
292 struct bio_vec;
293 typedef int (dma_drain_needed_fn)(struct request *);
294 
295 enum blk_eh_timer_return {
296         BLK_EH_DONE,            /* drivers has completed the command */
297         BLK_EH_RESET_TIMER,     /* reset timer and try again */
298 };
299 
300 enum blk_queue_state {
301         Queue_down,
302         Queue_up,
303 };
304 
305 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
306 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
307 
308 #define BLK_SCSI_MAX_CMDS       (256)
309 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
310 
311 /*
312  * Zoned block device models (zoned limit).
313  */
314 enum blk_zoned_model {
315         BLK_ZONED_NONE, /* Regular block device */
316         BLK_ZONED_HA,   /* Host-aware zoned block device */
317         BLK_ZONED_HM,   /* Host-managed zoned block device */
318 };
319 
320 struct queue_limits {
321         unsigned long           bounce_pfn;
322         unsigned long           seg_boundary_mask;
323         unsigned long           virt_boundary_mask;
324 
325         unsigned int            max_hw_sectors;
326         unsigned int            max_dev_sectors;
327         unsigned int            chunk_sectors;
328         unsigned int            max_sectors;
329         unsigned int            max_segment_size;
330         unsigned int            physical_block_size;
331         unsigned int            logical_block_size;
332         unsigned int            alignment_offset;
333         unsigned int            io_min;
334         unsigned int            io_opt;
335         unsigned int            max_discard_sectors;
336         unsigned int            max_hw_discard_sectors;
337         unsigned int            max_write_same_sectors;
338         unsigned int            max_write_zeroes_sectors;
339         unsigned int            discard_granularity;
340         unsigned int            discard_alignment;
341 
342         unsigned short          max_segments;
343         unsigned short          max_integrity_segments;
344         unsigned short          max_discard_segments;
345 
346         unsigned char           misaligned;
347         unsigned char           discard_misaligned;
348         unsigned char           raid_partial_stripes_expensive;
349         enum blk_zoned_model    zoned;
350 };
351 
352 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
353                                void *data);
354 
355 #ifdef CONFIG_BLK_DEV_ZONED
356 
357 #define BLK_ALL_ZONES  ((unsigned int)-1)
358 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
359                         unsigned int nr_zones, report_zones_cb cb, void *data);
360 unsigned int blkdev_nr_zones(struct gendisk *disk);
361 extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
362                             sector_t sectors, sector_t nr_sectors,
363                             gfp_t gfp_mask);
364 extern int blk_revalidate_disk_zones(struct gendisk *disk);
365 
366 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
367                                      unsigned int cmd, unsigned long arg);
368 extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
369                                   unsigned int cmd, unsigned long arg);
370 
371 #else /* CONFIG_BLK_DEV_ZONED */
372 
373 static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
374 {
375         return 0;
376 }
377 
378 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
379                                             fmode_t mode, unsigned int cmd,
380                                             unsigned long arg)
381 {
382         return -ENOTTY;
383 }
384 
385 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
386                                          fmode_t mode, unsigned int cmd,
387                                          unsigned long arg)
388 {
389         return -ENOTTY;
390 }
391 
392 #endif /* CONFIG_BLK_DEV_ZONED */
393 
394 struct request_queue {
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 
409         unsigned int            queue_depth;
410 
411         /* hw dispatch queues */
412         struct blk_mq_hw_ctx    **queue_hw_ctx;
413         unsigned int            nr_hw_queues;
414 
415         struct backing_dev_info *backing_dev_info;
416 
417         /*
418          * The queue owner gets to use this for whatever they like.
419          * ll_rw_blk doesn't touch it.
420          */
421         void                    *queuedata;
422 
423         /*
424          * various queue flags, see QUEUE_* below
425          */
426         unsigned long           queue_flags;
427         /*
428          * Number of contexts that have called blk_set_pm_only(). If this
429          * counter is above zero then only RQF_PM and RQF_PREEMPT requests are
430          * processed.
431          */
432         atomic_t                pm_only;
433 
434         /*
435          * ida allocated id for this queue.  Used to index queues from
436          * ioctx.
437          */
438         int                     id;
439 
440         /*
441          * queue needs bounce pages for pages above this limit
442          */
443         gfp_t                   bounce_gfp;
444 
445         spinlock_t              queue_lock;
446 
447         /*
448          * queue kobject
449          */
450         struct kobject kobj;
451 
452         /*
453          * mq queue kobject
454          */
455         struct kobject *mq_kobj;
456 
457 #ifdef  CONFIG_BLK_DEV_INTEGRITY
458         struct blk_integrity integrity;
459 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
460 
461 #ifdef CONFIG_PM
462         struct device           *dev;
463         int                     rpm_status;
464         unsigned int            nr_pending;
465 #endif
466 
467         /*
468          * queue settings
469          */
470         unsigned long           nr_requests;    /* Max # of requests */
471 
472         unsigned int            dma_drain_size;
473         void                    *dma_drain_buffer;
474         unsigned int            dma_pad_mask;
475         unsigned int            dma_alignment;
476 
477         unsigned int            rq_timeout;
478         int                     poll_nsec;
479 
480         struct blk_stat_callback        *poll_cb;
481         struct blk_rq_stat      poll_stat[BLK_MQ_POLL_STATS_BKTS];
482 
483         struct timer_list       timeout;
484         struct work_struct      timeout_work;
485 
486         struct list_head        icq_list;
487 #ifdef CONFIG_BLK_CGROUP
488         DECLARE_BITMAP          (blkcg_pols, BLKCG_MAX_POLS);
489         struct blkcg_gq         *root_blkg;
490         struct list_head        blkg_list;
491 #endif
492 
493         struct queue_limits     limits;
494 
495         unsigned int            required_elevator_features;
496 
497 #ifdef CONFIG_BLK_DEV_ZONED
498         /*
499          * Zoned block device information for request dispatch control.
500          * nr_zones is the total number of zones of the device. This is always
501          * 0 for regular block devices. conv_zones_bitmap is a bitmap of nr_zones
502          * bits which indicates if a zone is conventional (bit set) or
503          * sequential (bit clear). seq_zones_wlock is a bitmap of nr_zones
504          * bits which indicates if a zone is write locked, that is, if a write
505          * request targeting the zone was dispatched. All three fields are
506          * initialized by the low level device driver (e.g. scsi/sd.c).
507          * Stacking drivers (device mappers) may or may not initialize
508          * these fields.
509          *
510          * Reads of this information must be protected with blk_queue_enter() /
511          * blk_queue_exit(). Modifying this information is only allowed while
512          * no requests are being processed. See also blk_mq_freeze_queue() and
513          * blk_mq_unfreeze_queue().
514          */
515         unsigned int            nr_zones;
516         unsigned long           *conv_zones_bitmap;
517         unsigned long           *seq_zones_wlock;
518 #endif /* CONFIG_BLK_DEV_ZONED */
519 
520         /*
521          * sg stuff
522          */
523         unsigned int            sg_timeout;
524         unsigned int            sg_reserved_size;
525         int                     node;
526 #ifdef CONFIG_BLK_DEV_IO_TRACE
527         struct blk_trace __rcu  *blk_trace;
528         struct mutex            blk_trace_mutex;
529 #endif
530         /*
531          * for flush operations
532          */
533         struct blk_flush_queue  *fq;
534 
535         struct list_head        requeue_list;
536         spinlock_t              requeue_lock;
537         struct delayed_work     requeue_work;
538 
539         struct mutex            sysfs_lock;
540         struct mutex            sysfs_dir_lock;
541 
542         /*
543          * for reusing dead hctx instance in case of updating
544          * nr_hw_queues
545          */
546         struct list_head        unused_hctx_list;
547         spinlock_t              unused_hctx_lock;
548 
549         int                     mq_freeze_depth;
550 
551 #if defined(CONFIG_BLK_DEV_BSG)
552         struct bsg_class_device bsg_dev;
553 #endif
554 
555 #ifdef CONFIG_BLK_DEV_THROTTLING
556         /* Throttle data */
557         struct throtl_data *td;
558 #endif
559         struct rcu_head         rcu_head;
560         wait_queue_head_t       mq_freeze_wq;
561         /*
562          * Protect concurrent access to q_usage_counter by
563          * percpu_ref_kill() and percpu_ref_reinit().
564          */
565         struct mutex            mq_freeze_lock;
566         struct percpu_ref       q_usage_counter;
567 
568         struct blk_mq_tag_set   *tag_set;
569         struct list_head        tag_set_list;
570         struct bio_set          bio_split;
571 
572 #ifdef CONFIG_BLK_DEBUG_FS
573         struct dentry           *debugfs_dir;
574         struct dentry           *sched_debugfs_dir;
575         struct dentry           *rqos_debugfs_dir;
576 #endif
577 
578         bool                    mq_sysfs_init_done;
579 
580         size_t                  cmd_size;
581 
582         struct work_struct      release_work;
583 
584 #define BLK_MAX_WRITE_HINTS     5
585         u64                     write_hints[BLK_MAX_WRITE_HINTS];
586 };
587 
588 /* Keep blk_queue_flag_name[] in sync with the definitions below */
589 #define QUEUE_FLAG_STOPPED      0       /* queue is stopped */
590 #define QUEUE_FLAG_DYING        1       /* queue being torn down */
591 #define QUEUE_FLAG_NOMERGES     3       /* disable merge attempts */
592 #define QUEUE_FLAG_SAME_COMP    4       /* complete on same CPU-group */
593 #define QUEUE_FLAG_FAIL_IO      5       /* fake timeout */
594 #define QUEUE_FLAG_NONROT       6       /* non-rotational device (SSD) */
595 #define QUEUE_FLAG_VIRT         QUEUE_FLAG_NONROT /* paravirt device */
596 #define QUEUE_FLAG_IO_STAT      7       /* do disk/partitions IO accounting */
597 #define QUEUE_FLAG_DISCARD      8       /* supports DISCARD */
598 #define QUEUE_FLAG_NOXMERGES    9       /* No extended merges */
599 #define QUEUE_FLAG_ADD_RANDOM   10      /* Contributes to random pool */
600 #define QUEUE_FLAG_SECERASE     11      /* supports secure erase */
601 #define QUEUE_FLAG_SAME_FORCE   12      /* force complete on same CPU */
602 #define QUEUE_FLAG_DEAD         13      /* queue tear-down finished */
603 #define QUEUE_FLAG_INIT_DONE    14      /* queue is initialized */
604 #define QUEUE_FLAG_POLL         16      /* IO polling enabled if set */
605 #define QUEUE_FLAG_WC           17      /* Write back caching */
606 #define QUEUE_FLAG_FUA          18      /* device supports FUA writes */
607 #define QUEUE_FLAG_DAX          19      /* device supports DAX */
608 #define QUEUE_FLAG_STATS        20      /* track IO start and completion times */
609 #define QUEUE_FLAG_POLL_STATS   21      /* collecting stats for hybrid polling */
610 #define QUEUE_FLAG_REGISTERED   22      /* queue has been registered to a disk */
611 #define QUEUE_FLAG_SCSI_PASSTHROUGH 23  /* queue supports SCSI commands */
612 #define QUEUE_FLAG_QUIESCED     24      /* queue has been quiesced */
613 #define QUEUE_FLAG_PCI_P2PDMA   25      /* device supports PCI p2p requests */
614 #define QUEUE_FLAG_ZONE_RESETALL 26     /* supports Zone Reset All */
615 #define QUEUE_FLAG_RQ_ALLOC_TIME 27     /* record rq->alloc_time_ns */
616 
617 #define QUEUE_FLAG_MQ_DEFAULT   ((1 << QUEUE_FLAG_IO_STAT) |            \
618                                  (1 << QUEUE_FLAG_SAME_COMP))
619 
620 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
621 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
622 bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
623 
624 #define blk_queue_stopped(q)    test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
625 #define blk_queue_dying(q)      test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
626 #define blk_queue_dead(q)       test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
627 #define blk_queue_init_done(q)  test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
628 #define blk_queue_nomerges(q)   test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
629 #define blk_queue_noxmerges(q)  \
630         test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
631 #define blk_queue_nonrot(q)     test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
632 #define blk_queue_io_stat(q)    test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
633 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
634 #define blk_queue_discard(q)    test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
635 #define blk_queue_zone_resetall(q)      \
636         test_bit(QUEUE_FLAG_ZONE_RESETALL, &(q)->queue_flags)
637 #define blk_queue_secure_erase(q) \
638         (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
639 #define blk_queue_dax(q)        test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
640 #define blk_queue_scsi_passthrough(q)   \
641         test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
642 #define blk_queue_pci_p2pdma(q) \
643         test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
644 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
645 #define blk_queue_rq_alloc_time(q)      \
646         test_bit(QUEUE_FLAG_RQ_ALLOC_TIME, &(q)->queue_flags)
647 #else
648 #define blk_queue_rq_alloc_time(q)      false
649 #endif
650 
651 #define blk_noretry_request(rq) \
652         ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
653                              REQ_FAILFAST_DRIVER))
654 #define blk_queue_quiesced(q)   test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
655 #define blk_queue_pm_only(q)    atomic_read(&(q)->pm_only)
656 #define blk_queue_fua(q)        test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
657 #define blk_queue_registered(q) test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags)
658 
659 extern void blk_set_pm_only(struct request_queue *q);
660 extern void blk_clear_pm_only(struct request_queue *q);
661 
662 static inline bool blk_account_rq(struct request *rq)
663 {
664         return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
665 }
666 
667 #define list_entry_rq(ptr)      list_entry((ptr), struct request, queuelist)
668 
669 #define rq_data_dir(rq)         (op_is_write(req_op(rq)) ? WRITE : READ)
670 
671 #define rq_dma_dir(rq) \
672         (op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
673 
674 #define dma_map_bvec(dev, bv, dir, attrs) \
675         dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
676         (dir), (attrs))
677 
678 static inline bool queue_is_mq(struct request_queue *q)
679 {
680         return q->mq_ops;
681 }
682 
683 static inline enum blk_zoned_model
684 blk_queue_zoned_model(struct request_queue *q)
685 {
686         return q->limits.zoned;
687 }
688 
689 static inline bool blk_queue_is_zoned(struct request_queue *q)
690 {
691         switch (blk_queue_zoned_model(q)) {
692         case BLK_ZONED_HA:
693         case BLK_ZONED_HM:
694                 return true;
695         default:
696                 return false;
697         }
698 }
699 
700 static inline sector_t blk_queue_zone_sectors(struct request_queue *q)
701 {
702         return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
703 }
704 
705 #ifdef CONFIG_BLK_DEV_ZONED
706 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
707 {
708         return blk_queue_is_zoned(q) ? q->nr_zones : 0;
709 }
710 
711 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
712                                              sector_t sector)
713 {
714         if (!blk_queue_is_zoned(q))
715                 return 0;
716         return sector >> ilog2(q->limits.chunk_sectors);
717 }
718 
719 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
720                                          sector_t sector)
721 {
722         if (!blk_queue_is_zoned(q))
723                 return false;
724         if (!q->conv_zones_bitmap)
725                 return true;
726         return !test_bit(blk_queue_zone_no(q, sector), q->conv_zones_bitmap);
727 }
728 #else /* CONFIG_BLK_DEV_ZONED */
729 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
730 {
731         return 0;
732 }
733 #endif /* CONFIG_BLK_DEV_ZONED */
734 
735 static inline bool rq_is_sync(struct request *rq)
736 {
737         return op_is_sync(rq->cmd_flags);
738 }
739 
740 static inline bool rq_mergeable(struct request *rq)
741 {
742         if (blk_rq_is_passthrough(rq))
743                 return false;
744 
745         if (req_op(rq) == REQ_OP_FLUSH)
746                 return false;
747 
748         if (req_op(rq) == REQ_OP_WRITE_ZEROES)
749                 return false;
750 
751         if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
752                 return false;
753         if (rq->rq_flags & RQF_NOMERGE_FLAGS)
754                 return false;
755 
756         return true;
757 }
758 
759 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
760 {
761         if (bio_page(a) == bio_page(b) &&
762             bio_offset(a) == bio_offset(b))
763                 return true;
764 
765         return false;
766 }
767 
768 static inline unsigned int blk_queue_depth(struct request_queue *q)
769 {
770         if (q->queue_depth)
771                 return q->queue_depth;
772 
773         return q->nr_requests;
774 }
775 
776 extern unsigned long blk_max_low_pfn, blk_max_pfn;
777 
778 /*
779  * standard bounce addresses:
780  *
781  * BLK_BOUNCE_HIGH      : bounce all highmem pages
782  * BLK_BOUNCE_ANY       : don't bounce anything
783  * BLK_BOUNCE_ISA       : bounce pages above ISA DMA boundary
784  */
785 
786 #if BITS_PER_LONG == 32
787 #define BLK_BOUNCE_HIGH         ((u64)blk_max_low_pfn << PAGE_SHIFT)
788 #else
789 #define BLK_BOUNCE_HIGH         -1ULL
790 #endif
791 #define BLK_BOUNCE_ANY          (-1ULL)
792 #define BLK_BOUNCE_ISA          (DMA_BIT_MASK(24))
793 
794 /*
795  * default timeout for SG_IO if none specified
796  */
797 #define BLK_DEFAULT_SG_TIMEOUT  (60 * HZ)
798 #define BLK_MIN_SG_TIMEOUT      (7 * HZ)
799 
800 struct rq_map_data {
801         struct page **pages;
802         int page_order;
803         int nr_entries;
804         unsigned long offset;
805         int null_mapped;
806         int from_user;
807 };
808 
809 struct req_iterator {
810         struct bvec_iter iter;
811         struct bio *bio;
812 };
813 
814 /* This should not be used directly - use rq_for_each_segment */
815 #define for_each_bio(_bio)              \
816         for (; _bio; _bio = _bio->bi_next)
817 #define __rq_for_each_bio(_bio, rq)     \
818         if ((rq->bio))                  \
819                 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
820 
821 #define rq_for_each_segment(bvl, _rq, _iter)                    \
822         __rq_for_each_bio(_iter.bio, _rq)                       \
823                 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
824 
825 #define rq_for_each_bvec(bvl, _rq, _iter)                       \
826         __rq_for_each_bio(_iter.bio, _rq)                       \
827                 bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
828 
829 #define rq_iter_last(bvec, _iter)                               \
830                 (_iter.bio->bi_next == NULL &&                  \
831                  bio_iter_last(bvec, _iter.iter))
832 
833 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
834 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
835 #endif
836 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
837 extern void rq_flush_dcache_pages(struct request *rq);
838 #else
839 static inline void rq_flush_dcache_pages(struct request *rq)
840 {
841 }
842 #endif
843 
844 extern int blk_register_queue(struct gendisk *disk);
845 extern void blk_unregister_queue(struct gendisk *disk);
846 extern blk_qc_t generic_make_request(struct bio *bio);
847 extern blk_qc_t direct_make_request(struct bio *bio);
848 extern void blk_rq_init(struct request_queue *q, struct request *rq);
849 extern void blk_put_request(struct request *);
850 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
851                                        blk_mq_req_flags_t flags);
852 extern int blk_lld_busy(struct request_queue *q);
853 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
854                              struct bio_set *bs, gfp_t gfp_mask,
855                              int (*bio_ctr)(struct bio *, struct bio *, void *),
856                              void *data);
857 extern void blk_rq_unprep_clone(struct request *rq);
858 extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
859                                      struct request *rq);
860 extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
861 extern void blk_queue_split(struct request_queue *, struct bio **);
862 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
863 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
864                               unsigned int, void __user *);
865 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
866                           unsigned int, void __user *);
867 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
868                          struct scsi_ioctl_command __user *);
869 extern int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp);
870 extern int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp);
871 
872 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
873 extern void blk_queue_exit(struct request_queue *q);
874 extern void blk_sync_queue(struct request_queue *q);
875 extern int blk_rq_map_user(struct request_queue *, struct request *,
876                            struct rq_map_data *, void __user *, unsigned long,
877                            gfp_t);
878 extern int blk_rq_unmap_user(struct bio *);
879 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
880 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
881                                struct rq_map_data *, const struct iov_iter *,
882                                gfp_t);
883 extern void blk_execute_rq(struct request_queue *, struct gendisk *,
884                           struct request *, int);
885 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
886                                   struct request *, int, rq_end_io_fn *);
887 
888 /* Helper to convert REQ_OP_XXX to its string format XXX */
889 extern const char *blk_op_str(unsigned int op);
890 
891 int blk_status_to_errno(blk_status_t status);
892 blk_status_t errno_to_blk_status(int errno);
893 
894 int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin);
895 
896 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
897 {
898         return bdev->bd_disk->queue;    /* this is never NULL */
899 }
900 
901 /*
902  * The basic unit of block I/O is a sector. It is used in a number of contexts
903  * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
904  * bytes. Variables of type sector_t represent an offset or size that is a
905  * multiple of 512 bytes. Hence these two constants.
906  */
907 #ifndef SECTOR_SHIFT
908 #define SECTOR_SHIFT 9
909 #endif
910 #ifndef SECTOR_SIZE
911 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
912 #endif
913 
914 /*
915  * blk_rq_pos()                 : the current sector
916  * blk_rq_bytes()               : bytes left in the entire request
917  * blk_rq_cur_bytes()           : bytes left in the current segment
918  * blk_rq_err_bytes()           : bytes left till the next error boundary
919  * blk_rq_sectors()             : sectors left in the entire request
920  * blk_rq_cur_sectors()         : sectors left in the current segment
921  * blk_rq_stats_sectors()       : sectors of the entire request used for stats
922  */
923 static inline sector_t blk_rq_pos(const struct request *rq)
924 {
925         return rq->__sector;
926 }
927 
928 static inline unsigned int blk_rq_bytes(const struct request *rq)
929 {
930         return rq->__data_len;
931 }
932 
933 static inline int blk_rq_cur_bytes(const struct request *rq)
934 {
935         return rq->bio ? bio_cur_bytes(rq->bio) : 0;
936 }
937 
938 extern unsigned int blk_rq_err_bytes(const struct request *rq);
939 
940 static inline unsigned int blk_rq_sectors(const struct request *rq)
941 {
942         return blk_rq_bytes(rq) >> SECTOR_SHIFT;
943 }
944 
945 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
946 {
947         return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
948 }
949 
950 static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
951 {
952         return rq->stats_sectors;
953 }
954 
955 #ifdef CONFIG_BLK_DEV_ZONED
956 
957 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */
958 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond);
959 
960 static inline unsigned int blk_rq_zone_no(struct request *rq)
961 {
962         return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
963 }
964 
965 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
966 {
967         return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
968 }
969 #endif /* CONFIG_BLK_DEV_ZONED */
970 
971 /*
972  * Some commands like WRITE SAME have a payload or data transfer size which
973  * is different from the size of the request.  Any driver that supports such
974  * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
975  * calculate the data transfer size.
976  */
977 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
978 {
979         if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
980                 return rq->special_vec.bv_len;
981         return blk_rq_bytes(rq);
982 }
983 
984 /*
985  * Return the first full biovec in the request.  The caller needs to check that
986  * there are any bvecs before calling this helper.
987  */
988 static inline struct bio_vec req_bvec(struct request *rq)
989 {
990         if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
991                 return rq->special_vec;
992         return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
993 }
994 
995 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
996                                                      int op)
997 {
998         if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
999                 return min(q->limits.max_discard_sectors,
1000                            UINT_MAX >> SECTOR_SHIFT);
1001 
1002         if (unlikely(op == REQ_OP_WRITE_SAME))
1003                 return q->limits.max_write_same_sectors;
1004 
1005         if (unlikely(op == REQ_OP_WRITE_ZEROES))
1006                 return q->limits.max_write_zeroes_sectors;
1007 
1008         return q->limits.max_sectors;
1009 }
1010 
1011 /*
1012  * Return maximum size of a request at given offset. Only valid for
1013  * file system requests.
1014  */
1015 static inline unsigned int blk_max_size_offset(struct request_queue *q,
1016                                                sector_t offset)
1017 {
1018         if (!q->limits.chunk_sectors)
1019                 return q->limits.max_sectors;
1020 
1021         return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
1022                         (offset & (q->limits.chunk_sectors - 1))));
1023 }
1024 
1025 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
1026                                                   sector_t offset)
1027 {
1028         struct request_queue *q = rq->q;
1029 
1030         if (blk_rq_is_passthrough(rq))
1031                 return q->limits.max_hw_sectors;
1032 
1033         if (!q->limits.chunk_sectors ||
1034             req_op(rq) == REQ_OP_DISCARD ||
1035             req_op(rq) == REQ_OP_SECURE_ERASE)
1036                 return blk_queue_get_max_sectors(q, req_op(rq));
1037 
1038         return min(blk_max_size_offset(q, offset),
1039                         blk_queue_get_max_sectors(q, req_op(rq)));
1040 }
1041 
1042 static inline unsigned int blk_rq_count_bios(struct request *rq)
1043 {
1044         unsigned int nr_bios = 0;
1045         struct bio *bio;
1046 
1047         __rq_for_each_bio(bio, rq)
1048                 nr_bios++;
1049 
1050         return nr_bios;
1051 }
1052 
1053 void blk_steal_bios(struct bio_list *list, struct request *rq);
1054 
1055 /*
1056  * Request completion related functions.
1057  *
1058  * blk_update_request() completes given number of bytes and updates
1059  * the request without completing it.
1060  */
1061 extern bool blk_update_request(struct request *rq, blk_status_t error,
1062                                unsigned int nr_bytes);
1063 
1064 extern void __blk_complete_request(struct request *);
1065 extern void blk_abort_request(struct request *);
1066 
1067 /*
1068  * Access functions for manipulating queue properties
1069  */
1070 extern void blk_cleanup_queue(struct request_queue *);
1071 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1072 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1073 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1074 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1075 extern void blk_queue_max_discard_segments(struct request_queue *,
1076                 unsigned short);
1077 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1078 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1079                 unsigned int max_discard_sectors);
1080 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1081                 unsigned int max_write_same_sectors);
1082 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1083                 unsigned int max_write_same_sectors);
1084 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1085 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1086 extern void blk_queue_alignment_offset(struct request_queue *q,
1087                                        unsigned int alignment);
1088 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1089 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1090 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1091 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1092 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1093 extern void blk_set_default_limits(struct queue_limits *lim);
1094 extern void blk_set_stacking_limits(struct queue_limits *lim);
1095 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1096                             sector_t offset);
1097 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1098                             sector_t offset);
1099 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1100                               sector_t offset);
1101 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1102 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1103 extern int blk_queue_dma_drain(struct request_queue *q,
1104                                dma_drain_needed_fn *dma_drain_needed,
1105                                void *buf, unsigned int size);
1106 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1107 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1108 extern void blk_queue_dma_alignment(struct request_queue *, int);
1109 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1110 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1111 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1112 extern void blk_queue_required_elevator_features(struct request_queue *q,
1113                                                  unsigned int features);
1114 extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q,
1115                                               struct device *dev);
1116 
1117 /*
1118  * Number of physical segments as sent to the device.
1119  *
1120  * Normally this is the number of discontiguous data segments sent by the
1121  * submitter.  But for data-less command like discard we might have no
1122  * actual data segments submitted, but the driver might have to add it's
1123  * own special payload.  In that case we still return 1 here so that this
1124  * special payload will be mapped.
1125  */
1126 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1127 {
1128         if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1129                 return 1;
1130         return rq->nr_phys_segments;
1131 }
1132 
1133 /*
1134  * Number of discard segments (or ranges) the driver needs to fill in.
1135  * Each discard bio merged into a request is counted as one segment.
1136  */
1137 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1138 {
1139         return max_t(unsigned short, rq->nr_phys_segments, 1);
1140 }
1141 
1142 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1143 extern void blk_dump_rq_flags(struct request *, char *);
1144 extern long nr_blockdev_pages(void);
1145 
1146 bool __must_check blk_get_queue(struct request_queue *);
1147 struct request_queue *blk_alloc_queue(make_request_fn make_request, int node_id);
1148 extern void blk_put_queue(struct request_queue *);
1149 extern void blk_set_queue_dying(struct request_queue *);
1150 
1151 /*
1152  * blk_plug permits building a queue of related requests by holding the I/O
1153  * fragments for a short period. This allows merging of sequential requests
1154  * into single larger request. As the requests are moved from a per-task list to
1155  * the device's request_queue in a batch, this results in improved scalability
1156  * as the lock contention for request_queue lock is reduced.
1157  *
1158  * It is ok not to disable preemption when adding the request to the plug list
1159  * or when attempting a merge, because blk_schedule_flush_list() will only flush
1160  * the plug list when the task sleeps by itself. For details, please see
1161  * schedule() where blk_schedule_flush_plug() is called.
1162  */
1163 struct blk_plug {
1164         struct list_head mq_list; /* blk-mq requests */
1165         struct list_head cb_list; /* md requires an unplug callback */
1166         unsigned short rq_count;
1167         bool multiple_queues;
1168 };
1169 #define BLK_MAX_REQUEST_COUNT 16
1170 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1171 
1172 struct blk_plug_cb;
1173 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1174 struct blk_plug_cb {
1175         struct list_head list;
1176         blk_plug_cb_fn callback;
1177         void *data;
1178 };
1179 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1180                                              void *data, int size);
1181 extern void blk_start_plug(struct blk_plug *);
1182 extern void blk_finish_plug(struct blk_plug *);
1183 extern void blk_flush_plug_list(struct blk_plug *, bool);
1184 
1185 static inline void blk_flush_plug(struct task_struct *tsk)
1186 {
1187         struct blk_plug *plug = tsk->plug;
1188 
1189         if (plug)
1190                 blk_flush_plug_list(plug, false);
1191 }
1192 
1193 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1194 {
1195         struct blk_plug *plug = tsk->plug;
1196 
1197         if (plug)
1198                 blk_flush_plug_list(plug, true);
1199 }
1200 
1201 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1202 {
1203         struct blk_plug *plug = tsk->plug;
1204 
1205         return plug &&
1206                  (!list_empty(&plug->mq_list) ||
1207                  !list_empty(&plug->cb_list));
1208 }
1209 
1210 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1211 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1212                 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1213 
1214 #define BLKDEV_DISCARD_SECURE   (1 << 0)        /* issue a secure erase */
1215 
1216 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1217                 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1218 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1219                 sector_t nr_sects, gfp_t gfp_mask, int flags,
1220                 struct bio **biop);
1221 
1222 #define BLKDEV_ZERO_NOUNMAP     (1 << 0)  /* do not free blocks */
1223 #define BLKDEV_ZERO_NOFALLBACK  (1 << 1)  /* don't write explicit zeroes */
1224 
1225 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1226                 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1227                 unsigned flags);
1228 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1229                 sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1230 
1231 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1232                 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1233 {
1234         return blkdev_issue_discard(sb->s_bdev,
1235                                     block << (sb->s_blocksize_bits -
1236                                               SECTOR_SHIFT),
1237                                     nr_blocks << (sb->s_blocksize_bits -
1238                                                   SECTOR_SHIFT),
1239                                     gfp_mask, flags);
1240 }
1241 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1242                 sector_t nr_blocks, gfp_t gfp_mask)
1243 {
1244         return blkdev_issue_zeroout(sb->s_bdev,
1245                                     block << (sb->s_blocksize_bits -
1246                                               SECTOR_SHIFT),
1247                                     nr_blocks << (sb->s_blocksize_bits -
1248                                                   SECTOR_SHIFT),
1249                                     gfp_mask, 0);
1250 }
1251 
1252 extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1253 
1254 enum blk_default_limits {
1255         BLK_MAX_SEGMENTS        = 128,
1256         BLK_SAFE_MAX_SECTORS    = 255,
1257         BLK_DEF_MAX_SECTORS     = 2560,
1258         BLK_MAX_SEGMENT_SIZE    = 65536,
1259         BLK_SEG_BOUNDARY_MASK   = 0xFFFFFFFFUL,
1260 };
1261 
1262 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
1263 {
1264         return q->limits.seg_boundary_mask;
1265 }
1266 
1267 static inline unsigned long queue_virt_boundary(const struct request_queue *q)
1268 {
1269         return q->limits.virt_boundary_mask;
1270 }
1271 
1272 static inline unsigned int queue_max_sectors(const struct request_queue *q)
1273 {
1274         return q->limits.max_sectors;
1275 }
1276 
1277 static inline unsigned int queue_max_hw_sectors(const struct request_queue *q)
1278 {
1279         return q->limits.max_hw_sectors;
1280 }
1281 
1282 static inline unsigned short queue_max_segments(const struct request_queue *q)
1283 {
1284         return q->limits.max_segments;
1285 }
1286 
1287 static inline unsigned short queue_max_discard_segments(const struct request_queue *q)
1288 {
1289         return q->limits.max_discard_segments;
1290 }
1291 
1292 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
1293 {
1294         return q->limits.max_segment_size;
1295 }
1296 
1297 static inline unsigned queue_logical_block_size(const struct request_queue *q)
1298 {
1299         int retval = 512;
1300 
1301         if (q && q->limits.logical_block_size)
1302                 retval = q->limits.logical_block_size;
1303 
1304         return retval;
1305 }
1306 
1307 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1308 {
1309         return queue_logical_block_size(bdev_get_queue(bdev));
1310 }
1311 
1312 static inline unsigned int queue_physical_block_size(const struct request_queue *q)
1313 {
1314         return q->limits.physical_block_size;
1315 }
1316 
1317 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1318 {
1319         return queue_physical_block_size(bdev_get_queue(bdev));
1320 }
1321 
1322 static inline unsigned int queue_io_min(const struct request_queue *q)
1323 {
1324         return q->limits.io_min;
1325 }
1326 
1327 static inline int bdev_io_min(struct block_device *bdev)
1328 {
1329         return queue_io_min(bdev_get_queue(bdev));
1330 }
1331 
1332 static inline unsigned int queue_io_opt(const struct request_queue *q)
1333 {
1334         return q->limits.io_opt;
1335 }
1336 
1337 static inline int bdev_io_opt(struct block_device *bdev)
1338 {
1339         return queue_io_opt(bdev_get_queue(bdev));
1340 }
1341 
1342 static inline int queue_alignment_offset(const struct request_queue *q)
1343 {
1344         if (q->limits.misaligned)
1345                 return -1;
1346 
1347         return q->limits.alignment_offset;
1348 }
1349 
1350 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1351 {
1352         unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1353         unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1354                 << SECTOR_SHIFT;
1355 
1356         return (granularity + lim->alignment_offset - alignment) % granularity;
1357 }
1358 
1359 static inline int bdev_alignment_offset(struct block_device *bdev)
1360 {
1361         struct request_queue *q = bdev_get_queue(bdev);
1362 
1363         if (q->limits.misaligned)
1364                 return -1;
1365 
1366         if (bdev != bdev->bd_contains)
1367                 return bdev->bd_part->alignment_offset;
1368 
1369         return q->limits.alignment_offset;
1370 }
1371 
1372 static inline int queue_discard_alignment(const struct request_queue *q)
1373 {
1374         if (q->limits.discard_misaligned)
1375                 return -1;
1376 
1377         return q->limits.discard_alignment;
1378 }
1379 
1380 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1381 {
1382         unsigned int alignment, granularity, offset;
1383 
1384         if (!lim->max_discard_sectors)
1385                 return 0;
1386 
1387         /* Why are these in bytes, not sectors? */
1388         alignment = lim->discard_alignment >> SECTOR_SHIFT;
1389         granularity = lim->discard_granularity >> SECTOR_SHIFT;
1390         if (!granularity)
1391                 return 0;
1392 
1393         /* Offset of the partition start in 'granularity' sectors */
1394         offset = sector_div(sector, granularity);
1395 
1396         /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1397         offset = (granularity + alignment - offset) % granularity;
1398 
1399         /* Turn it back into bytes, gaah */
1400         return offset << SECTOR_SHIFT;
1401 }
1402 
1403 static inline int bdev_discard_alignment(struct block_device *bdev)
1404 {
1405         struct request_queue *q = bdev_get_queue(bdev);
1406 
1407         if (bdev != bdev->bd_contains)
1408                 return bdev->bd_part->discard_alignment;
1409 
1410         return q->limits.discard_alignment;
1411 }
1412 
1413 static inline unsigned int bdev_write_same(struct block_device *bdev)
1414 {
1415         struct request_queue *q = bdev_get_queue(bdev);
1416 
1417         if (q)
1418                 return q->limits.max_write_same_sectors;
1419 
1420         return 0;
1421 }
1422 
1423 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1424 {
1425         struct request_queue *q = bdev_get_queue(bdev);
1426 
1427         if (q)
1428                 return q->limits.max_write_zeroes_sectors;
1429 
1430         return 0;
1431 }
1432 
1433 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1434 {
1435         struct request_queue *q = bdev_get_queue(bdev);
1436 
1437         if (q)
1438                 return blk_queue_zoned_model(q);
1439 
1440         return BLK_ZONED_NONE;
1441 }
1442 
1443 static inline bool bdev_is_zoned(struct block_device *bdev)
1444 {
1445         struct request_queue *q = bdev_get_queue(bdev);
1446 
1447         if (q)
1448                 return blk_queue_is_zoned(q);
1449 
1450         return false;
1451 }
1452 
1453 static inline sector_t bdev_zone_sectors(struct block_device *bdev)
1454 {
1455         struct request_queue *q = bdev_get_queue(bdev);
1456 
1457         if (q)
1458                 return blk_queue_zone_sectors(q);
1459         return 0;
1460 }
1461 
1462 static inline int queue_dma_alignment(const struct request_queue *q)
1463 {
1464         return q ? q->dma_alignment : 511;
1465 }
1466 
1467 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1468                                  unsigned int len)
1469 {
1470         unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1471         return !(addr & alignment) && !(len & alignment);
1472 }
1473 
1474 /* assumes size > 256 */
1475 static inline unsigned int blksize_bits(unsigned int size)
1476 {
1477         unsigned int bits = 8;
1478         do {
1479                 bits++;
1480                 size >>= 1;
1481         } while (size > 256);
1482         return bits;
1483 }
1484 
1485 static inline unsigned int block_size(struct block_device *bdev)
1486 {
1487         return bdev->bd_block_size;
1488 }
1489 
1490 int kblockd_schedule_work(struct work_struct *work);
1491 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1492 
1493 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1494         MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1495 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1496         MODULE_ALIAS("block-major-" __stringify(major) "-*")
1497 
1498 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1499 
1500 enum blk_integrity_flags {
1501         BLK_INTEGRITY_VERIFY            = 1 << 0,
1502         BLK_INTEGRITY_GENERATE          = 1 << 1,
1503         BLK_INTEGRITY_DEVICE_CAPABLE    = 1 << 2,
1504         BLK_INTEGRITY_IP_CHECKSUM       = 1 << 3,
1505 };
1506 
1507 struct blk_integrity_iter {
1508         void                    *prot_buf;
1509         void                    *data_buf;
1510         sector_t                seed;
1511         unsigned int            data_size;
1512         unsigned short          interval;
1513         const char              *disk_name;
1514 };
1515 
1516 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1517 typedef void (integrity_prepare_fn) (struct request *);
1518 typedef void (integrity_complete_fn) (struct request *, unsigned int);
1519 
1520 struct blk_integrity_profile {
1521         integrity_processing_fn         *generate_fn;
1522         integrity_processing_fn         *verify_fn;
1523         integrity_prepare_fn            *prepare_fn;
1524         integrity_complete_fn           *complete_fn;
1525         const char                      *name;
1526 };
1527 
1528 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1529 extern void blk_integrity_unregister(struct gendisk *);
1530 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1531 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1532                                    struct scatterlist *);
1533 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1534 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1535                                    struct request *);
1536 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1537                                     struct bio *);
1538 
1539 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1540 {
1541         struct blk_integrity *bi = &disk->queue->integrity;
1542 
1543         if (!bi->profile)
1544                 return NULL;
1545 
1546         return bi;
1547 }
1548 
1549 static inline
1550 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1551 {
1552         return blk_get_integrity(bdev->bd_disk);
1553 }
1554 
1555 static inline bool blk_integrity_rq(struct request *rq)
1556 {
1557         return rq->cmd_flags & REQ_INTEGRITY;
1558 }
1559 
1560 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1561                                                     unsigned int segs)
1562 {
1563         q->limits.max_integrity_segments = segs;
1564 }
1565 
1566 static inline unsigned short
1567 queue_max_integrity_segments(const struct request_queue *q)
1568 {
1569         return q->limits.max_integrity_segments;
1570 }
1571 
1572 /**
1573  * bio_integrity_intervals - Return number of integrity intervals for a bio
1574  * @bi:         blk_integrity profile for device
1575  * @sectors:    Size of the bio in 512-byte sectors
1576  *
1577  * Description: The block layer calculates everything in 512 byte
1578  * sectors but integrity metadata is done in terms of the data integrity
1579  * interval size of the storage device.  Convert the block layer sectors
1580  * to the appropriate number of integrity intervals.
1581  */
1582 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1583                                                    unsigned int sectors)
1584 {
1585         return sectors >> (bi->interval_exp - 9);
1586 }
1587 
1588 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1589                                                unsigned int sectors)
1590 {
1591         return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1592 }
1593 
1594 /*
1595  * Return the first bvec that contains integrity data.  Only drivers that are
1596  * limited to a single integrity segment should use this helper.
1597  */
1598 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1599 {
1600         if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
1601                 return NULL;
1602         return rq->bio->bi_integrity->bip_vec;
1603 }
1604 
1605 #else /* CONFIG_BLK_DEV_INTEGRITY */
1606 
1607 struct bio;
1608 struct block_device;
1609 struct gendisk;
1610 struct blk_integrity;
1611 
1612 static inline int blk_integrity_rq(struct request *rq)
1613 {
1614         return 0;
1615 }
1616 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1617                                             struct bio *b)
1618 {
1619         return 0;
1620 }
1621 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1622                                           struct bio *b,
1623                                           struct scatterlist *s)
1624 {
1625         return 0;
1626 }
1627 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1628 {
1629         return NULL;
1630 }
1631 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1632 {
1633         return NULL;
1634 }
1635 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1636 {
1637         return 0;
1638 }
1639 static inline void blk_integrity_register(struct gendisk *d,
1640                                          struct blk_integrity *b)
1641 {
1642 }
1643 static inline void blk_integrity_unregister(struct gendisk *d)
1644 {
1645 }
1646 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1647                                                     unsigned int segs)
1648 {
1649 }
1650 static inline unsigned short queue_max_integrity_segments(const struct request_queue *q)
1651 {
1652         return 0;
1653 }
1654 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1655                                           struct request *r1,
1656                                           struct request *r2)
1657 {
1658         return true;
1659 }
1660 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1661                                            struct request *r,
1662                                            struct bio *b)
1663 {
1664         return true;
1665 }
1666 
1667 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1668                                                    unsigned int sectors)
1669 {
1670         return 0;
1671 }
1672 
1673 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1674                                                unsigned int sectors)
1675 {
1676         return 0;
1677 }
1678 
1679 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1680 {
1681         return NULL;
1682 }
1683 
1684 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1685 
1686 struct block_device_operations {
1687         int (*open) (struct block_device *, fmode_t);
1688         void (*release) (struct gendisk *, fmode_t);
1689         int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1690         int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1691         int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1692         unsigned int (*check_events) (struct gendisk *disk,
1693                                       unsigned int clearing);
1694         /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1695         int (*media_changed) (struct gendisk *);
1696         void (*unlock_native_capacity) (struct gendisk *);
1697         int (*revalidate_disk) (struct gendisk *);
1698         int (*getgeo)(struct block_device *, struct hd_geometry *);
1699         /* this callback is with swap_lock and sometimes page table lock held */
1700         void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1701         int (*report_zones)(struct gendisk *, sector_t sector,
1702                         unsigned int nr_zones, report_zones_cb cb, void *data);
1703         char *(*devnode)(struct gendisk *disk, umode_t *mode);
1704         struct module *owner;
1705         const struct pr_ops *pr_ops;
1706 };
1707 
1708 #ifdef CONFIG_COMPAT
1709 extern int blkdev_compat_ptr_ioctl(struct block_device *, fmode_t,
1710                                       unsigned int, unsigned long);
1711 #else
1712 #define blkdev_compat_ptr_ioctl NULL
1713 #endif
1714 
1715 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1716                                  unsigned long);
1717 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1718 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1719                                                 struct writeback_control *);
1720 
1721 #ifdef CONFIG_BLK_DEV_ZONED
1722 bool blk_req_needs_zone_write_lock(struct request *rq);
1723 void __blk_req_zone_write_lock(struct request *rq);
1724 void __blk_req_zone_write_unlock(struct request *rq);
1725 
1726 static inline void blk_req_zone_write_lock(struct request *rq)
1727 {
1728         if (blk_req_needs_zone_write_lock(rq))
1729                 __blk_req_zone_write_lock(rq);
1730 }
1731 
1732 static inline void blk_req_zone_write_unlock(struct request *rq)
1733 {
1734         if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1735                 __blk_req_zone_write_unlock(rq);
1736 }
1737 
1738 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1739 {
1740         return rq->q->seq_zones_wlock &&
1741                 test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
1742 }
1743 
1744 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1745 {
1746         if (!blk_req_needs_zone_write_lock(rq))
1747                 return true;
1748         return !blk_req_zone_is_write_locked(rq);
1749 }
1750 #else
1751 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1752 {
1753         return false;
1754 }
1755 
1756 static inline void blk_req_zone_write_lock(struct request *rq)
1757 {
1758 }
1759 
1760 static inline void blk_req_zone_write_unlock(struct request *rq)
1761 {
1762 }
1763 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1764 {
1765         return false;
1766 }
1767 
1768 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1769 {
1770         return true;
1771 }
1772 #endif /* CONFIG_BLK_DEV_ZONED */
1773 
1774 #else /* CONFIG_BLOCK */
1775 
1776 struct block_device;
1777 
1778 /*
1779  * stubs for when the block layer is configured out
1780  */
1781 #define buffer_heads_over_limit 0
1782 
1783 static inline long nr_blockdev_pages(void)
1784 {
1785         return 0;
1786 }
1787 
1788 struct blk_plug {
1789 };
1790 
1791 static inline void blk_start_plug(struct blk_plug *plug)
1792 {
1793 }
1794 
1795 static inline void blk_finish_plug(struct blk_plug *plug)
1796 {
1797 }
1798 
1799 static inline void blk_flush_plug(struct task_struct *task)
1800 {
1801 }
1802 
1803 static inline void blk_schedule_flush_plug(struct task_struct *task)
1804 {
1805 }
1806 
1807 
1808 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1809 {
1810         return false;
1811 }
1812 
1813 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1814                                      sector_t *error_sector)
1815 {
1816         return 0;
1817 }
1818 
1819 #endif /* CONFIG_BLOCK */
1820 
1821 static inline void blk_wake_io_task(struct task_struct *waiter)
1822 {
1823         /*
1824          * If we're polling, the task itself is doing the completions. For
1825          * that case, we don't need to signal a wakeup, it's enough to just
1826          * mark us as RUNNING.
1827          */
1828         if (waiter == current)
1829                 __set_current_state(TASK_RUNNING);
1830         else
1831                 wake_up_process(waiter);
1832 }
1833 
1834 #endif
1835 

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