1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <linux/blkdev.h>
6 #include <linux/sbitmap.h>
7 #include <linux/lockdep.h>
8 #include <linux/scatterlist.h>
9 #include <linux/prefetch.h>
10 #include <linux/srcu.h>
13 struct blk_flush_queue;
15 #define BLKDEV_MIN_RQ 4
16 #define BLKDEV_DEFAULT_RQ 128
23 typedef enum rq_end_io_ret (rq_end_io_fn)(struct request *, blk_status_t);
27 typedef __u32 __bitwise req_flags_t;
29 /* drive already may have started this one */
30 #define RQF_STARTED ((__force req_flags_t)(1 << 1))
31 /* may not be passed by ioscheduler */
32 #define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3))
33 /* request for flush sequence */
34 #define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4))
35 /* merge of different types, fail separately */
36 #define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5))
37 /* track inflight for MQ */
38 #define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6))
39 /* don't call prep for this one */
40 #define RQF_DONTPREP ((__force req_flags_t)(1 << 7))
41 /* vaguely specified driver internal error. Ignored by the block layer */
42 #define RQF_FAILED ((__force req_flags_t)(1 << 10))
43 /* don't warn about errors */
44 #define RQF_QUIET ((__force req_flags_t)(1 << 11))
45 /* elevator private data attached */
46 #define RQF_ELVPRIV ((__force req_flags_t)(1 << 12))
47 /* account into disk and partition IO statistics */
48 #define RQF_IO_STAT ((__force req_flags_t)(1 << 13))
49 /* runtime pm request */
50 #define RQF_PM ((__force req_flags_t)(1 << 15))
51 /* on IO scheduler merge hash */
52 #define RQF_HASHED ((__force req_flags_t)(1 << 16))
53 /* track IO completion time */
54 #define RQF_STATS ((__force req_flags_t)(1 << 17))
55 /* Look at ->special_vec for the actual data payload instead of the
57 #define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18))
58 /* The per-zone write lock is held for this request */
59 #define RQF_ZONE_WRITE_LOCKED ((__force req_flags_t)(1 << 19))
60 /* ->timeout has been called, don't expire again */
61 #define RQF_TIMED_OUT ((__force req_flags_t)(1 << 21))
62 /* queue has elevator attached */
63 #define RQF_ELV ((__force req_flags_t)(1 << 22))
64 #define RQF_RESV ((__force req_flags_t)(1 << 23))
66 /* flags that prevent us from merging requests: */
67 #define RQF_NOMERGE_FLAGS \
68 (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
77 * Try to put the fields that are referenced together in the same cacheline.
79 * If you modify this structure, make sure to update blk_rq_init() and
80 * especially blk_mq_rq_ctx_init() to take care of the added fields.
83 struct request_queue *q;
84 struct blk_mq_ctx *mq_ctx;
85 struct blk_mq_hw_ctx *mq_hctx;
87 blk_opf_t cmd_flags; /* op and common flags */
95 /* the following two fields are internal, NEVER access directly */
96 unsigned int __data_len; /* total data len */
97 sector_t __sector; /* sector cursor */
103 struct list_head queuelist;
104 struct request *rq_next;
107 struct block_device *part;
108 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
109 /* Time that the first bio started allocating this request. */
112 /* Time that this request was allocated for this IO. */
114 /* Time that I/O was submitted to the device. */
115 u64 io_start_time_ns;
117 #ifdef CONFIG_BLK_WBT
118 unsigned short wbt_flags;
121 * rq sectors used for blk stats. It has the same value
122 * with blk_rq_sectors(rq), except that it never be zeroed
125 unsigned short stats_sectors;
128 * Number of scatter-gather DMA addr+len pairs after
129 * physical address coalescing is performed.
131 unsigned short nr_phys_segments;
133 #ifdef CONFIG_BLK_DEV_INTEGRITY
134 unsigned short nr_integrity_segments;
137 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
138 struct bio_crypt_ctx *crypt_ctx;
139 struct blk_crypto_keyslot *crypt_keyslot;
142 unsigned short ioprio;
144 enum mq_rq_state state;
147 unsigned long deadline;
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).
157 struct hlist_node hash; /* merge hash */
158 struct llist_node ipi_list;
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.
167 struct rb_node rb_node; /* sort/lookup */
168 struct bio_vec special_vec;
169 void *completion_data;
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.
187 struct list_head list;
188 rq_end_io_fn *saved_end_io;
193 struct __call_single_data csd;
198 * completion callback.
200 rq_end_io_fn *end_io;
204 static inline enum req_op req_op(const struct request *req)
206 return req->cmd_flags & REQ_OP_MASK;
209 static inline bool blk_rq_is_passthrough(struct request *rq)
211 return blk_op_is_passthrough(req_op(rq));
214 static inline unsigned short req_get_ioprio(struct request *req)
219 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
221 #define rq_dma_dir(rq) \
222 (op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
224 #define rq_list_add(listptr, rq) do { \
225 (rq)->rq_next = *(listptr); \
229 #define rq_list_add_tail(lastpptr, rq) do { \
230 (rq)->rq_next = NULL; \
232 *(lastpptr) = &rq->rq_next; \
235 #define rq_list_pop(listptr) \
237 struct request *__req = NULL; \
238 if ((listptr) && *(listptr)) { \
239 __req = *(listptr); \
240 *(listptr) = __req->rq_next; \
245 #define rq_list_peek(listptr) \
247 struct request *__req = NULL; \
248 if ((listptr) && *(listptr)) \
249 __req = *(listptr); \
253 #define rq_list_for_each(listptr, pos) \
254 for (pos = rq_list_peek((listptr)); pos; pos = rq_list_next(pos))
256 #define rq_list_for_each_safe(listptr, pos, nxt) \
257 for (pos = rq_list_peek((listptr)), nxt = rq_list_next(pos); \
258 pos; pos = nxt, nxt = pos ? rq_list_next(pos) : NULL)
260 #define rq_list_next(rq) (rq)->rq_next
261 #define rq_list_empty(list) ((list) == (struct request *) NULL)
264 * rq_list_move() - move a struct request from one list to another
265 * @src: The source list @rq is currently in
266 * @dst: The destination list that @rq will be appended to
267 * @rq: The request to move
268 * @prev: The request preceding @rq in @src (NULL if @rq is the head)
270 static inline void rq_list_move(struct request **src, struct request **dst,
271 struct request *rq, struct request *prev)
274 prev->rq_next = rq->rq_next;
277 rq_list_add(dst, rq);
281 * enum blk_eh_timer_return - How the timeout handler should proceed
282 * @BLK_EH_DONE: The block driver completed the command or will complete it at
284 * @BLK_EH_RESET_TIMER: Reset the request timer and continue waiting for the
285 * request to complete.
287 enum blk_eh_timer_return {
292 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
293 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
296 * struct blk_mq_hw_ctx - State for a hardware queue facing the hardware
299 struct blk_mq_hw_ctx {
301 /** @lock: Protects the dispatch list. */
304 * @dispatch: Used for requests that are ready to be
305 * dispatched to the hardware but for some reason (e.g. lack of
306 * resources) could not be sent to the hardware. As soon as the
307 * driver can send new requests, requests at this list will
308 * be sent first for a fairer dispatch.
310 struct list_head dispatch;
312 * @state: BLK_MQ_S_* flags. Defines the state of the hw
313 * queue (active, scheduled to restart, stopped).
316 } ____cacheline_aligned_in_smp;
319 * @run_work: Used for scheduling a hardware queue run at a later time.
321 struct delayed_work run_work;
322 /** @cpumask: Map of available CPUs where this hctx can run. */
323 cpumask_var_t cpumask;
325 * @next_cpu: Used by blk_mq_hctx_next_cpu() for round-robin CPU
326 * selection from @cpumask.
330 * @next_cpu_batch: Counter of how many works left in the batch before
331 * changing to the next CPU.
335 /** @flags: BLK_MQ_F_* flags. Defines the behaviour of the queue. */
339 * @sched_data: Pointer owned by the IO scheduler attached to a request
340 * queue. It's up to the IO scheduler how to use this pointer.
344 * @queue: Pointer to the request queue that owns this hardware context.
346 struct request_queue *queue;
347 /** @fq: Queue of requests that need to perform a flush operation. */
348 struct blk_flush_queue *fq;
351 * @driver_data: Pointer to data owned by the block driver that created
357 * @ctx_map: Bitmap for each software queue. If bit is on, there is a
358 * pending request in that software queue.
360 struct sbitmap ctx_map;
363 * @dispatch_from: Software queue to be used when no scheduler was
366 struct blk_mq_ctx *dispatch_from;
368 * @dispatch_busy: Number used by blk_mq_update_dispatch_busy() to
369 * decide if the hw_queue is busy using Exponential Weighted Moving
372 unsigned int dispatch_busy;
374 /** @type: HCTX_TYPE_* flags. Type of hardware queue. */
376 /** @nr_ctx: Number of software queues. */
377 unsigned short nr_ctx;
378 /** @ctxs: Array of software queues. */
379 struct blk_mq_ctx **ctxs;
381 /** @dispatch_wait_lock: Lock for dispatch_wait queue. */
382 spinlock_t dispatch_wait_lock;
384 * @dispatch_wait: Waitqueue to put requests when there is no tag
385 * available at the moment, to wait for another try in the future.
387 wait_queue_entry_t dispatch_wait;
390 * @wait_index: Index of next available dispatch_wait queue to insert
396 * @tags: Tags owned by the block driver. A tag at this set is only
397 * assigned when a request is dispatched from a hardware queue.
399 struct blk_mq_tags *tags;
401 * @sched_tags: Tags owned by I/O scheduler. If there is an I/O
402 * scheduler associated with a request queue, a tag is assigned when
403 * that request is allocated. Else, this member is not used.
405 struct blk_mq_tags *sched_tags;
407 /** @queued: Number of queued requests. */
408 unsigned long queued;
409 /** @run: Number of dispatched requests. */
412 /** @numa_node: NUMA node the storage adapter has been connected to. */
413 unsigned int numa_node;
414 /** @queue_num: Index of this hardware queue. */
415 unsigned int queue_num;
418 * @nr_active: Number of active requests. Only used when a tag set is
419 * shared across request queues.
423 /** @cpuhp_online: List to store request if CPU is going to die */
424 struct hlist_node cpuhp_online;
425 /** @cpuhp_dead: List to store request if some CPU die. */
426 struct hlist_node cpuhp_dead;
427 /** @kobj: Kernel object for sysfs. */
430 #ifdef CONFIG_BLK_DEBUG_FS
432 * @debugfs_dir: debugfs directory for this hardware queue. Named
433 * as cpu<cpu_number>.
435 struct dentry *debugfs_dir;
436 /** @sched_debugfs_dir: debugfs directory for the scheduler. */
437 struct dentry *sched_debugfs_dir;
441 * @hctx_list: if this hctx is not in use, this is an entry in
442 * q->unused_hctx_list.
444 struct list_head hctx_list;
448 * struct blk_mq_queue_map - Map software queues to hardware queues
449 * @mq_map: CPU ID to hardware queue index map. This is an array
450 * with nr_cpu_ids elements. Each element has a value in the range
451 * [@queue_offset, @queue_offset + @nr_queues).
452 * @nr_queues: Number of hardware queues to map CPU IDs onto.
453 * @queue_offset: First hardware queue to map onto. Used by the PCIe NVMe
454 * driver to map each hardware queue type (enum hctx_type) onto a distinct
455 * set of hardware queues.
457 struct blk_mq_queue_map {
458 unsigned int *mq_map;
459 unsigned int nr_queues;
460 unsigned int queue_offset;
464 * enum hctx_type - Type of hardware queue
465 * @HCTX_TYPE_DEFAULT: All I/O not otherwise accounted for.
466 * @HCTX_TYPE_READ: Just for READ I/O.
467 * @HCTX_TYPE_POLL: Polled I/O of any kind.
468 * @HCTX_MAX_TYPES: Number of types of hctx.
479 * struct blk_mq_tag_set - tag set that can be shared between request queues
480 * @ops: Pointers to functions that implement block driver behavior.
481 * @map: One or more ctx -> hctx mappings. One map exists for each
482 * hardware queue type (enum hctx_type) that the driver wishes
483 * to support. There are no restrictions on maps being of the
484 * same size, and it's perfectly legal to share maps between
486 * @nr_maps: Number of elements in the @map array. A number in the range
487 * [1, HCTX_MAX_TYPES].
488 * @nr_hw_queues: Number of hardware queues supported by the block driver that
489 * owns this data structure.
490 * @queue_depth: Number of tags per hardware queue, reserved tags included.
491 * @reserved_tags: Number of tags to set aside for BLK_MQ_REQ_RESERVED tag
493 * @cmd_size: Number of additional bytes to allocate per request. The block
494 * driver owns these additional bytes.
495 * @numa_node: NUMA node the storage adapter has been connected to.
496 * @timeout: Request processing timeout in jiffies.
497 * @flags: Zero or more BLK_MQ_F_* flags.
498 * @driver_data: Pointer to data owned by the block driver that created this
500 * @tags: Tag sets. One tag set per hardware queue. Has @nr_hw_queues
503 * Shared set of tags. Has @nr_hw_queues elements. If set,
504 * shared by all @tags.
505 * @tag_list_lock: Serializes tag_list accesses.
506 * @tag_list: List of the request queues that use this tag set. See also
507 * request_queue.tag_set_list.
508 * @srcu: Use as lock when type of the request queue is blocking
509 * (BLK_MQ_F_BLOCKING).
511 struct blk_mq_tag_set {
512 const struct blk_mq_ops *ops;
513 struct blk_mq_queue_map map[HCTX_MAX_TYPES];
514 unsigned int nr_maps;
515 unsigned int nr_hw_queues;
516 unsigned int queue_depth;
517 unsigned int reserved_tags;
518 unsigned int cmd_size;
520 unsigned int timeout;
524 struct blk_mq_tags **tags;
526 struct blk_mq_tags *shared_tags;
528 struct mutex tag_list_lock;
529 struct list_head tag_list;
530 struct srcu_struct *srcu;
534 * struct blk_mq_queue_data - Data about a request inserted in a queue
536 * @rq: Request pointer.
537 * @last: If it is the last request in the queue.
539 struct blk_mq_queue_data {
544 typedef bool (busy_tag_iter_fn)(struct request *, void *);
547 * struct blk_mq_ops - Callback functions that implements block driver
552 * @queue_rq: Queue a new request from block IO.
554 blk_status_t (*queue_rq)(struct blk_mq_hw_ctx *,
555 const struct blk_mq_queue_data *);
558 * @commit_rqs: If a driver uses bd->last to judge when to submit
559 * requests to hardware, it must define this function. In case of errors
560 * that make us stop issuing further requests, this hook serves the
561 * purpose of kicking the hardware (which the last request otherwise
564 void (*commit_rqs)(struct blk_mq_hw_ctx *);
567 * @queue_rqs: Queue a list of new requests. Driver is guaranteed
568 * that each request belongs to the same queue. If the driver doesn't
569 * empty the @rqlist completely, then the rest will be queued
570 * individually by the block layer upon return.
572 void (*queue_rqs)(struct request **rqlist);
575 * @get_budget: Reserve budget before queue request, once .queue_rq is
576 * run, it is driver's responsibility to release the
577 * reserved budget. Also we have to handle failure case
578 * of .get_budget for avoiding I/O deadlock.
580 int (*get_budget)(struct request_queue *);
583 * @put_budget: Release the reserved budget.
585 void (*put_budget)(struct request_queue *, int);
588 * @set_rq_budget_token: store rq's budget token
590 void (*set_rq_budget_token)(struct request *, int);
592 * @get_rq_budget_token: retrieve rq's budget token
594 int (*get_rq_budget_token)(struct request *);
597 * @timeout: Called on request timeout.
599 enum blk_eh_timer_return (*timeout)(struct request *);
602 * @poll: Called to poll for completion of a specific tag.
604 int (*poll)(struct blk_mq_hw_ctx *, struct io_comp_batch *);
607 * @complete: Mark the request as complete.
609 void (*complete)(struct request *);
612 * @init_hctx: Called when the block layer side of a hardware queue has
613 * been set up, allowing the driver to allocate/init matching
616 int (*init_hctx)(struct blk_mq_hw_ctx *, void *, unsigned int);
618 * @exit_hctx: Ditto for exit/teardown.
620 void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);
623 * @init_request: Called for every command allocated by the block layer
624 * to allow the driver to set up driver specific data.
626 * Tag greater than or equal to queue_depth is for setting up
629 int (*init_request)(struct blk_mq_tag_set *set, struct request *,
630 unsigned int, unsigned int);
632 * @exit_request: Ditto for exit/teardown.
634 void (*exit_request)(struct blk_mq_tag_set *set, struct request *,
638 * @cleanup_rq: Called before freeing one request which isn't completed
639 * yet, and usually for freeing the driver private data.
641 void (*cleanup_rq)(struct request *);
644 * @busy: If set, returns whether or not this queue currently is busy.
646 bool (*busy)(struct request_queue *);
649 * @map_queues: This allows drivers specify their own queue mapping by
650 * overriding the setup-time function that builds the mq_map.
652 void (*map_queues)(struct blk_mq_tag_set *set);
654 #ifdef CONFIG_BLK_DEBUG_FS
656 * @show_rq: Used by the debugfs implementation to show driver-specific
657 * information about a request.
659 void (*show_rq)(struct seq_file *m, struct request *rq);
664 BLK_MQ_F_SHOULD_MERGE = 1 << 0,
665 BLK_MQ_F_TAG_QUEUE_SHARED = 1 << 1,
667 * Set when this device requires underlying blk-mq device for
670 BLK_MQ_F_STACKING = 1 << 2,
671 BLK_MQ_F_TAG_HCTX_SHARED = 1 << 3,
672 BLK_MQ_F_BLOCKING = 1 << 5,
673 /* Do not allow an I/O scheduler to be configured. */
674 BLK_MQ_F_NO_SCHED = 1 << 6,
676 * Select 'none' during queue registration in case of a single hwq
677 * or shared hwqs instead of 'mq-deadline'.
679 BLK_MQ_F_NO_SCHED_BY_DEFAULT = 1 << 7,
680 BLK_MQ_F_ALLOC_POLICY_START_BIT = 8,
681 BLK_MQ_F_ALLOC_POLICY_BITS = 1,
683 BLK_MQ_S_STOPPED = 0,
684 BLK_MQ_S_TAG_ACTIVE = 1,
685 BLK_MQ_S_SCHED_RESTART = 2,
687 /* hw queue is inactive after all its CPUs become offline */
688 BLK_MQ_S_INACTIVE = 3,
690 BLK_MQ_MAX_DEPTH = 10240,
692 BLK_MQ_CPU_WORK_BATCH = 8,
694 #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \
695 ((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \
696 ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1))
697 #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \
698 ((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \
699 << BLK_MQ_F_ALLOC_POLICY_START_BIT)
701 #define BLK_MQ_NO_HCTX_IDX (-1U)
703 struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata,
704 struct lock_class_key *lkclass);
705 #define blk_mq_alloc_disk(set, queuedata) \
707 static struct lock_class_key __key; \
709 __blk_mq_alloc_disk(set, queuedata, &__key); \
711 struct gendisk *blk_mq_alloc_disk_for_queue(struct request_queue *q,
712 struct lock_class_key *lkclass);
713 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *);
714 int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
715 struct request_queue *q);
716 void blk_mq_destroy_queue(struct request_queue *);
718 int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set);
719 int blk_mq_alloc_sq_tag_set(struct blk_mq_tag_set *set,
720 const struct blk_mq_ops *ops, unsigned int queue_depth,
721 unsigned int set_flags);
722 void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
724 void blk_mq_free_request(struct request *rq);
726 bool blk_mq_queue_inflight(struct request_queue *q);
729 /* return when out of requests */
730 BLK_MQ_REQ_NOWAIT = (__force blk_mq_req_flags_t)(1 << 0),
731 /* allocate from reserved pool */
732 BLK_MQ_REQ_RESERVED = (__force blk_mq_req_flags_t)(1 << 1),
734 BLK_MQ_REQ_PM = (__force blk_mq_req_flags_t)(1 << 2),
737 struct request *blk_mq_alloc_request(struct request_queue *q, blk_opf_t opf,
738 blk_mq_req_flags_t flags);
739 struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
740 blk_opf_t opf, blk_mq_req_flags_t flags,
741 unsigned int hctx_idx);
744 * Tag address space map.
747 unsigned int nr_tags;
748 unsigned int nr_reserved_tags;
750 atomic_t active_queues;
752 struct sbitmap_queue bitmap_tags;
753 struct sbitmap_queue breserved_tags;
755 struct request **rqs;
756 struct request **static_rqs;
757 struct list_head page_list;
760 * used to clear request reference in rqs[] before freeing one
766 static inline struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags,
769 if (tag < tags->nr_tags) {
770 prefetch(tags->rqs[tag]);
771 return tags->rqs[tag];
778 BLK_MQ_UNIQUE_TAG_BITS = 16,
779 BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1,
782 u32 blk_mq_unique_tag(struct request *rq);
784 static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag)
786 return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS;
789 static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag)
791 return unique_tag & BLK_MQ_UNIQUE_TAG_MASK;
795 * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
796 * @rq: target request.
798 static inline enum mq_rq_state blk_mq_rq_state(struct request *rq)
800 return READ_ONCE(rq->state);
803 static inline int blk_mq_request_started(struct request *rq)
805 return blk_mq_rq_state(rq) != MQ_RQ_IDLE;
808 static inline int blk_mq_request_completed(struct request *rq)
810 return blk_mq_rq_state(rq) == MQ_RQ_COMPLETE;
815 * Set the state to complete when completing a request from inside ->queue_rq.
816 * This is used by drivers that want to ensure special complete actions that
817 * need access to the request are called on failure, e.g. by nvme for
820 static inline void blk_mq_set_request_complete(struct request *rq)
822 WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
826 * Complete the request directly instead of deferring it to softirq or
827 * completing it another CPU. Useful in preemptible instead of an interrupt.
829 static inline void blk_mq_complete_request_direct(struct request *rq,
830 void (*complete)(struct request *rq))
832 WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
836 void blk_mq_start_request(struct request *rq);
837 void blk_mq_end_request(struct request *rq, blk_status_t error);
838 void __blk_mq_end_request(struct request *rq, blk_status_t error);
839 void blk_mq_end_request_batch(struct io_comp_batch *ib);
842 * Only need start/end time stamping if we have iostat or
843 * blk stats enabled, or using an IO scheduler.
845 static inline bool blk_mq_need_time_stamp(struct request *rq)
847 return (rq->rq_flags & (RQF_IO_STAT | RQF_STATS | RQF_ELV));
850 static inline bool blk_mq_is_reserved_rq(struct request *rq)
852 return rq->rq_flags & RQF_RESV;
856 * Batched completions only work when there is no I/O error and no special
859 static inline bool blk_mq_add_to_batch(struct request *req,
860 struct io_comp_batch *iob, int ioerror,
861 void (*complete)(struct io_comp_batch *))
863 if (!iob || (req->rq_flags & RQF_ELV) || ioerror ||
864 (req->end_io && !blk_rq_is_passthrough(req)))
868 iob->complete = complete;
869 else if (iob->complete != complete)
871 iob->need_ts |= blk_mq_need_time_stamp(req);
872 rq_list_add(&iob->req_list, req);
876 void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list);
877 void blk_mq_kick_requeue_list(struct request_queue *q);
878 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
879 void blk_mq_complete_request(struct request *rq);
880 bool blk_mq_complete_request_remote(struct request *rq);
881 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
882 void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx);
883 void blk_mq_stop_hw_queues(struct request_queue *q);
884 void blk_mq_start_hw_queues(struct request_queue *q);
885 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
886 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
887 void blk_mq_quiesce_queue(struct request_queue *q);
888 void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set);
889 void blk_mq_quiesce_tagset(struct blk_mq_tag_set *set);
890 void blk_mq_unquiesce_tagset(struct blk_mq_tag_set *set);
891 void blk_mq_unquiesce_queue(struct request_queue *q);
892 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
893 void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
894 void blk_mq_run_hw_queues(struct request_queue *q, bool async);
895 void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs);
896 void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
897 busy_tag_iter_fn *fn, void *priv);
898 void blk_mq_tagset_wait_completed_request(struct blk_mq_tag_set *tagset);
899 void blk_mq_freeze_queue(struct request_queue *q);
900 void blk_mq_unfreeze_queue(struct request_queue *q);
901 void blk_freeze_queue_start(struct request_queue *q);
902 void blk_mq_freeze_queue_wait(struct request_queue *q);
903 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
904 unsigned long timeout);
906 void blk_mq_map_queues(struct blk_mq_queue_map *qmap);
907 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
909 void blk_mq_quiesce_queue_nowait(struct request_queue *q);
911 unsigned int blk_mq_rq_cpu(struct request *rq);
913 bool __blk_should_fake_timeout(struct request_queue *q);
914 static inline bool blk_should_fake_timeout(struct request_queue *q)
916 if (IS_ENABLED(CONFIG_FAIL_IO_TIMEOUT) &&
917 test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags))
918 return __blk_should_fake_timeout(q);
923 * blk_mq_rq_from_pdu - cast a PDU to a request
924 * @pdu: the PDU (Protocol Data Unit) to be casted
928 * Driver command data is immediately after the request. So subtract request
929 * size to get back to the original request.
931 static inline struct request *blk_mq_rq_from_pdu(void *pdu)
933 return pdu - sizeof(struct request);
937 * blk_mq_rq_to_pdu - cast a request to a PDU
938 * @rq: the request to be casted
940 * Return: pointer to the PDU
942 * Driver command data is immediately after the request. So add request to get
945 static inline void *blk_mq_rq_to_pdu(struct request *rq)
950 #define queue_for_each_hw_ctx(q, hctx, i) \
951 xa_for_each(&(q)->hctx_table, (i), (hctx))
953 #define hctx_for_each_ctx(hctx, ctx, i) \
954 for ((i) = 0; (i) < (hctx)->nr_ctx && \
955 ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++)
957 static inline void blk_mq_cleanup_rq(struct request *rq)
959 if (rq->q->mq_ops->cleanup_rq)
960 rq->q->mq_ops->cleanup_rq(rq);
963 static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
964 unsigned int nr_segs)
966 rq->nr_phys_segments = nr_segs;
967 rq->__data_len = bio->bi_iter.bi_size;
968 rq->bio = rq->biotail = bio;
969 rq->ioprio = bio_prio(bio);
972 void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx,
973 struct lock_class_key *key);
975 static inline bool rq_is_sync(struct request *rq)
977 return op_is_sync(rq->cmd_flags);
980 void blk_rq_init(struct request_queue *q, struct request *rq);
981 int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
982 struct bio_set *bs, gfp_t gfp_mask,
983 int (*bio_ctr)(struct bio *, struct bio *, void *), void *data);
984 void blk_rq_unprep_clone(struct request *rq);
985 blk_status_t blk_insert_cloned_request(struct request *rq);
989 unsigned long offset;
990 unsigned short page_order;
991 unsigned short nr_entries;
996 int blk_rq_map_user(struct request_queue *, struct request *,
997 struct rq_map_data *, void __user *, unsigned long, gfp_t);
998 int blk_rq_map_user_io(struct request *, struct rq_map_data *,
999 void __user *, unsigned long, gfp_t, bool, int, bool, int);
1000 int blk_rq_map_user_iov(struct request_queue *, struct request *,
1001 struct rq_map_data *, const struct iov_iter *, gfp_t);
1002 int blk_rq_unmap_user(struct bio *);
1003 int blk_rq_map_kern(struct request_queue *, struct request *, void *,
1004 unsigned int, gfp_t);
1005 int blk_rq_append_bio(struct request *rq, struct bio *bio);
1006 void blk_execute_rq_nowait(struct request *rq, bool at_head);
1007 blk_status_t blk_execute_rq(struct request *rq, bool at_head);
1008 bool blk_rq_is_poll(struct request *rq);
1010 struct req_iterator {
1011 struct bvec_iter iter;
1015 #define __rq_for_each_bio(_bio, rq) \
1017 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
1019 #define rq_for_each_segment(bvl, _rq, _iter) \
1020 __rq_for_each_bio(_iter.bio, _rq) \
1021 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
1023 #define rq_for_each_bvec(bvl, _rq, _iter) \
1024 __rq_for_each_bio(_iter.bio, _rq) \
1025 bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
1027 #define rq_iter_last(bvec, _iter) \
1028 (_iter.bio->bi_next == NULL && \
1029 bio_iter_last(bvec, _iter.iter))
1032 * blk_rq_pos() : the current sector
1033 * blk_rq_bytes() : bytes left in the entire request
1034 * blk_rq_cur_bytes() : bytes left in the current segment
1035 * blk_rq_sectors() : sectors left in the entire request
1036 * blk_rq_cur_sectors() : sectors left in the current segment
1037 * blk_rq_stats_sectors() : sectors of the entire request used for stats
1039 static inline sector_t blk_rq_pos(const struct request *rq)
1041 return rq->__sector;
1044 static inline unsigned int blk_rq_bytes(const struct request *rq)
1046 return rq->__data_len;
1049 static inline int blk_rq_cur_bytes(const struct request *rq)
1053 if (!bio_has_data(rq->bio)) /* dataless requests such as discard */
1054 return rq->bio->bi_iter.bi_size;
1055 return bio_iovec(rq->bio).bv_len;
1058 static inline unsigned int blk_rq_sectors(const struct request *rq)
1060 return blk_rq_bytes(rq) >> SECTOR_SHIFT;
1063 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
1065 return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
1068 static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
1070 return rq->stats_sectors;
1074 * Some commands like WRITE SAME have a payload or data transfer size which
1075 * is different from the size of the request. Any driver that supports such
1076 * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1077 * calculate the data transfer size.
1079 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1081 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1082 return rq->special_vec.bv_len;
1083 return blk_rq_bytes(rq);
1087 * Return the first full biovec in the request. The caller needs to check that
1088 * there are any bvecs before calling this helper.
1090 static inline struct bio_vec req_bvec(struct request *rq)
1092 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1093 return rq->special_vec;
1094 return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
1097 static inline unsigned int blk_rq_count_bios(struct request *rq)
1099 unsigned int nr_bios = 0;
1102 __rq_for_each_bio(bio, rq)
1108 void blk_steal_bios(struct bio_list *list, struct request *rq);
1111 * Request completion related functions.
1113 * blk_update_request() completes given number of bytes and updates
1114 * the request without completing it.
1116 bool blk_update_request(struct request *rq, blk_status_t error,
1117 unsigned int nr_bytes);
1118 void blk_abort_request(struct request *);
1121 * Number of physical segments as sent to the device.
1123 * Normally this is the number of discontiguous data segments sent by the
1124 * submitter. But for data-less command like discard we might have no
1125 * actual data segments submitted, but the driver might have to add it's
1126 * own special payload. In that case we still return 1 here so that this
1127 * special payload will be mapped.
1129 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1131 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1133 return rq->nr_phys_segments;
1137 * Number of discard segments (or ranges) the driver needs to fill in.
1138 * Each discard bio merged into a request is counted as one segment.
1140 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1142 return max_t(unsigned short, rq->nr_phys_segments, 1);
1145 int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
1146 struct scatterlist *sglist, struct scatterlist **last_sg);
1147 static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
1148 struct scatterlist *sglist)
1150 struct scatterlist *last_sg = NULL;
1152 return __blk_rq_map_sg(q, rq, sglist, &last_sg);
1154 void blk_dump_rq_flags(struct request *, char *);
1156 #ifdef CONFIG_BLK_DEV_ZONED
1157 static inline unsigned int blk_rq_zone_no(struct request *rq)
1159 return disk_zone_no(rq->q->disk, blk_rq_pos(rq));
1162 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
1164 return disk_zone_is_seq(rq->q->disk, blk_rq_pos(rq));
1167 bool blk_req_needs_zone_write_lock(struct request *rq);
1168 bool blk_req_zone_write_trylock(struct request *rq);
1169 void __blk_req_zone_write_lock(struct request *rq);
1170 void __blk_req_zone_write_unlock(struct request *rq);
1172 static inline void blk_req_zone_write_lock(struct request *rq)
1174 if (blk_req_needs_zone_write_lock(rq))
1175 __blk_req_zone_write_lock(rq);
1178 static inline void blk_req_zone_write_unlock(struct request *rq)
1180 if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1181 __blk_req_zone_write_unlock(rq);
1184 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1186 return rq->q->disk->seq_zones_wlock &&
1187 test_bit(blk_rq_zone_no(rq), rq->q->disk->seq_zones_wlock);
1190 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1192 if (!blk_req_needs_zone_write_lock(rq))
1194 return !blk_req_zone_is_write_locked(rq);
1196 #else /* CONFIG_BLK_DEV_ZONED */
1197 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1202 static inline void blk_req_zone_write_lock(struct request *rq)
1206 static inline void blk_req_zone_write_unlock(struct request *rq)
1209 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1214 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1218 #endif /* CONFIG_BLK_DEV_ZONED */
1220 #endif /* BLK_MQ_H */