1  /* SPDX-License-Identifier: GPL-2.0 */
2  #ifndef BLK_MQ_H
3  #define BLK_MQ_H
4  
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>
11  #include <linux/rw_hint.h>
12  
13  struct blk_mq_tags;
14  struct blk_flush_queue;
15  
16  #define BLKDEV_MIN_RQ	4
17  #define BLKDEV_DEFAULT_RQ	128
18  
19  enum rq_end_io_ret {
20  	RQ_END_IO_NONE,
21  	RQ_END_IO_FREE,
22  };
23  
24  typedef enum rq_end_io_ret (rq_end_io_fn)(struct request *, blk_status_t);
25  
26  /*
27   * request flags */
28  typedef __u32 __bitwise req_flags_t;
29  
30  /* Keep rqf_name[] in sync with the definitions below */
31  enum {
32  	/* drive already may have started this one */
33  	__RQF_STARTED,
34  	/* request for flush sequence */
35  	__RQF_FLUSH_SEQ,
36  	/* merge of different types, fail separately */
37  	__RQF_MIXED_MERGE,
38  	/* don't call prep for this one */
39  	__RQF_DONTPREP,
40  	/* use hctx->sched_tags */
41  	__RQF_SCHED_TAGS,
42  	/* use an I/O scheduler for this request */
43  	__RQF_USE_SCHED,
44  	/* vaguely specified driver internal error.  Ignored by block layer */
45  	__RQF_FAILED,
46  	/* don't warn about errors */
47  	__RQF_QUIET,
48  	/* account into disk and partition IO statistics */
49  	__RQF_IO_STAT,
50  	/* runtime pm request */
51  	__RQF_PM,
52  	/* on IO scheduler merge hash */
53  	__RQF_HASHED,
54  	/* track IO completion time */
55  	__RQF_STATS,
56  	/* Look at ->special_vec for the actual data payload instead of the
57  	   bio chain. */
58  	__RQF_SPECIAL_PAYLOAD,
59  	/* request completion needs to be signaled to zone write plugging. */
60  	__RQF_ZONE_WRITE_PLUGGING,
61  	/* ->timeout has been called, don't expire again */
62  	__RQF_TIMED_OUT,
63  	__RQF_RESV,
64  	__RQF_BITS
65  };
66  
67  #define RQF_STARTED		((__force req_flags_t)(1 << __RQF_STARTED))
68  #define RQF_FLUSH_SEQ		((__force req_flags_t)(1 << __RQF_FLUSH_SEQ))
69  #define RQF_MIXED_MERGE		((__force req_flags_t)(1 << __RQF_MIXED_MERGE))
70  #define RQF_DONTPREP		((__force req_flags_t)(1 << __RQF_DONTPREP))
71  #define RQF_SCHED_TAGS		((__force req_flags_t)(1 << __RQF_SCHED_TAGS))
72  #define RQF_USE_SCHED		((__force req_flags_t)(1 << __RQF_USE_SCHED))
73  #define RQF_FAILED		((__force req_flags_t)(1 << __RQF_FAILED))
74  #define RQF_QUIET		((__force req_flags_t)(1 << __RQF_QUIET))
75  #define RQF_IO_STAT		((__force req_flags_t)(1 << __RQF_IO_STAT))
76  #define RQF_PM			((__force req_flags_t)(1 << __RQF_PM))
77  #define RQF_HASHED		((__force req_flags_t)(1 << __RQF_HASHED))
78  #define RQF_STATS		((__force req_flags_t)(1 << __RQF_STATS))
79  #define RQF_SPECIAL_PAYLOAD	\
80  			((__force req_flags_t)(1 << __RQF_SPECIAL_PAYLOAD))
81  #define RQF_ZONE_WRITE_PLUGGING	\
82  			((__force req_flags_t)(1 << __RQF_ZONE_WRITE_PLUGGING))
83  #define RQF_TIMED_OUT		((__force req_flags_t)(1 << __RQF_TIMED_OUT))
84  #define RQF_RESV		((__force req_flags_t)(1 << __RQF_RESV))
85  
86  /* flags that prevent us from merging requests: */
87  #define RQF_NOMERGE_FLAGS \
88  	(RQF_STARTED | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
89  
90  enum mq_rq_state {
91  	MQ_RQ_IDLE		= 0,
92  	MQ_RQ_IN_FLIGHT		= 1,
93  	MQ_RQ_COMPLETE		= 2,
94  };
95  
96  /*
97   * Try to put the fields that are referenced together in the same cacheline.
98   *
99   * If you modify this structure, make sure to update blk_rq_init() and
100   * especially blk_mq_rq_ctx_init() to take care of the added fields.
101   */
102  struct request {
103  	struct request_queue *q;
104  	struct blk_mq_ctx *mq_ctx;
105  	struct blk_mq_hw_ctx *mq_hctx;
106  
107  	blk_opf_t cmd_flags;		/* op and common flags */
108  	req_flags_t rq_flags;
109  
110  	int tag;
111  	int internal_tag;
112  
113  	unsigned int timeout;
114  
115  	/* the following two fields are internal, NEVER access directly */
116  	unsigned int __data_len;	/* total data len */
117  	sector_t __sector;		/* sector cursor */
118  
119  	struct bio *bio;
120  	struct bio *biotail;
121  
122  	union {
123  		struct list_head queuelist;
124  		struct request *rq_next;
125  	};
126  
127  	struct block_device *part;
128  #ifdef CONFIG_BLK_RQ_ALLOC_TIME
129  	/* Time that the first bio started allocating this request. */
130  	u64 alloc_time_ns;
131  #endif
132  	/* Time that this request was allocated for this IO. */
133  	u64 start_time_ns;
134  	/* Time that I/O was submitted to the device. */
135  	u64 io_start_time_ns;
136  
137  #ifdef CONFIG_BLK_WBT
138  	unsigned short wbt_flags;
139  #endif
140  	/*
141  	 * rq sectors used for blk stats. It has the same value
142  	 * with blk_rq_sectors(rq), except that it never be zeroed
143  	 * by completion.
144  	 */
145  	unsigned short stats_sectors;
146  
147  	/*
148  	 * Number of scatter-gather DMA addr+len pairs after
149  	 * physical address coalescing is performed.
150  	 */
151  	unsigned short nr_phys_segments;
152  	unsigned short nr_integrity_segments;
153  
154  #ifdef CONFIG_BLK_INLINE_ENCRYPTION
155  	struct bio_crypt_ctx *crypt_ctx;
156  	struct blk_crypto_keyslot *crypt_keyslot;
157  #endif
158  
159  	enum rw_hint write_hint;
160  	unsigned short ioprio;
161  
162  	enum mq_rq_state state;
163  	atomic_t ref;
164  
165  	unsigned long deadline;
166  
167  	/*
168  	 * The hash is used inside the scheduler, and killed once the
169  	 * request reaches the dispatch list. The ipi_list is only used
170  	 * to queue the request for softirq completion, which is long
171  	 * after the request has been unhashed (and even removed from
172  	 * the dispatch list).
173  	 */
174  	union {
175  		struct hlist_node hash;	/* merge hash */
176  		struct llist_node ipi_list;
177  	};
178  
179  	/*
180  	 * The rb_node is only used inside the io scheduler, requests
181  	 * are pruned when moved to the dispatch queue. special_vec must
182  	 * only be used if RQF_SPECIAL_PAYLOAD is set, and those cannot be
183  	 * insert into an IO scheduler.
184  	 */
185  	union {
186  		struct rb_node rb_node;	/* sort/lookup */
187  		struct bio_vec special_vec;
188  	};
189  
190  	/*
191  	 * Three pointers are available for the IO schedulers, if they need
192  	 * more they have to dynamically allocate it.
193  	 */
194  	struct {
195  		struct io_cq		*icq;
196  		void			*priv[2];
197  	} elv;
198  
199  	struct {
200  		unsigned int		seq;
201  		rq_end_io_fn		*saved_end_io;
202  	} flush;
203  
204  	u64 fifo_time;
205  
206  	/*
207  	 * completion callback.
208  	 */
209  	rq_end_io_fn *end_io;
210  	void *end_io_data;
211  };
212  
req_op(const struct request * req)213  static inline enum req_op req_op(const struct request *req)
214  {
215  	return req->cmd_flags & REQ_OP_MASK;
216  }
217  
blk_rq_is_passthrough(struct request * rq)218  static inline bool blk_rq_is_passthrough(struct request *rq)
219  {
220  	return blk_op_is_passthrough(rq->cmd_flags);
221  }
222  
req_get_ioprio(struct request * req)223  static inline unsigned short req_get_ioprio(struct request *req)
224  {
225  	return req->ioprio;
226  }
227  
228  #define rq_data_dir(rq)		(op_is_write(req_op(rq)) ? WRITE : READ)
229  
230  #define rq_dma_dir(rq) \
231  	(op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
232  
233  #define rq_list_add(listptr, rq)	do {		\
234  	(rq)->rq_next = *(listptr);			\
235  	*(listptr) = rq;				\
236  } while (0)
237  
238  #define rq_list_add_tail(lastpptr, rq)	do {		\
239  	(rq)->rq_next = NULL;				\
240  	**(lastpptr) = rq;				\
241  	*(lastpptr) = &rq->rq_next;			\
242  } while (0)
243  
244  #define rq_list_pop(listptr)				\
245  ({							\
246  	struct request *__req = NULL;			\
247  	if ((listptr) && *(listptr))	{		\
248  		__req = *(listptr);			\
249  		*(listptr) = __req->rq_next;		\
250  	}						\
251  	__req;						\
252  })
253  
254  #define rq_list_peek(listptr)				\
255  ({							\
256  	struct request *__req = NULL;			\
257  	if ((listptr) && *(listptr))			\
258  		__req = *(listptr);			\
259  	__req;						\
260  })
261  
262  #define rq_list_for_each(listptr, pos)			\
263  	for (pos = rq_list_peek((listptr)); pos; pos = rq_list_next(pos))
264  
265  #define rq_list_for_each_safe(listptr, pos, nxt)			\
266  	for (pos = rq_list_peek((listptr)), nxt = rq_list_next(pos);	\
267  		pos; pos = nxt, nxt = pos ? rq_list_next(pos) : NULL)
268  
269  #define rq_list_next(rq)	(rq)->rq_next
270  #define rq_list_empty(list)	((list) == (struct request *) NULL)
271  
272  /**
273   * rq_list_move() - move a struct request from one list to another
274   * @src: The source list @rq is currently in
275   * @dst: The destination list that @rq will be appended to
276   * @rq: The request to move
277   * @prev: The request preceding @rq in @src (NULL if @rq is the head)
278   */
rq_list_move(struct request ** src,struct request ** dst,struct request * rq,struct request * prev)279  static inline void rq_list_move(struct request **src, struct request **dst,
280  				struct request *rq, struct request *prev)
281  {
282  	if (prev)
283  		prev->rq_next = rq->rq_next;
284  	else
285  		*src = rq->rq_next;
286  	rq_list_add(dst, rq);
287  }
288  
289  /**
290   * enum blk_eh_timer_return - How the timeout handler should proceed
291   * @BLK_EH_DONE: The block driver completed the command or will complete it at
292   *	a later time.
293   * @BLK_EH_RESET_TIMER: Reset the request timer and continue waiting for the
294   *	request to complete.
295   */
296  enum blk_eh_timer_return {
297  	BLK_EH_DONE,
298  	BLK_EH_RESET_TIMER,
299  };
300  
301  /* Keep alloc_policy_name[] in sync with the definitions below */
302  enum {
303  	BLK_TAG_ALLOC_FIFO,	/* allocate starting from 0 */
304  	BLK_TAG_ALLOC_RR,	/* allocate starting from last allocated tag */
305  	BLK_TAG_ALLOC_MAX
306  };
307  
308  /**
309   * struct blk_mq_hw_ctx - State for a hardware queue facing the hardware
310   * block device
311   */
312  struct blk_mq_hw_ctx {
313  	struct {
314  		/** @lock: Protects the dispatch list. */
315  		spinlock_t		lock;
316  		/**
317  		 * @dispatch: Used for requests that are ready to be
318  		 * dispatched to the hardware but for some reason (e.g. lack of
319  		 * resources) could not be sent to the hardware. As soon as the
320  		 * driver can send new requests, requests at this list will
321  		 * be sent first for a fairer dispatch.
322  		 */
323  		struct list_head	dispatch;
324  		 /**
325  		  * @state: BLK_MQ_S_* flags. Defines the state of the hw
326  		  * queue (active, scheduled to restart, stopped).
327  		  */
328  		unsigned long		state;
329  	} ____cacheline_aligned_in_smp;
330  
331  	/**
332  	 * @run_work: Used for scheduling a hardware queue run at a later time.
333  	 */
334  	struct delayed_work	run_work;
335  	/** @cpumask: Map of available CPUs where this hctx can run. */
336  	cpumask_var_t		cpumask;
337  	/**
338  	 * @next_cpu: Used by blk_mq_hctx_next_cpu() for round-robin CPU
339  	 * selection from @cpumask.
340  	 */
341  	int			next_cpu;
342  	/**
343  	 * @next_cpu_batch: Counter of how many works left in the batch before
344  	 * changing to the next CPU.
345  	 */
346  	int			next_cpu_batch;
347  
348  	/** @flags: BLK_MQ_F_* flags. Defines the behaviour of the queue. */
349  	unsigned long		flags;
350  
351  	/**
352  	 * @sched_data: Pointer owned by the IO scheduler attached to a request
353  	 * queue. It's up to the IO scheduler how to use this pointer.
354  	 */
355  	void			*sched_data;
356  	/**
357  	 * @queue: Pointer to the request queue that owns this hardware context.
358  	 */
359  	struct request_queue	*queue;
360  	/** @fq: Queue of requests that need to perform a flush operation. */
361  	struct blk_flush_queue	*fq;
362  
363  	/**
364  	 * @driver_data: Pointer to data owned by the block driver that created
365  	 * this hctx
366  	 */
367  	void			*driver_data;
368  
369  	/**
370  	 * @ctx_map: Bitmap for each software queue. If bit is on, there is a
371  	 * pending request in that software queue.
372  	 */
373  	struct sbitmap		ctx_map;
374  
375  	/**
376  	 * @dispatch_from: Software queue to be used when no scheduler was
377  	 * selected.
378  	 */
379  	struct blk_mq_ctx	*dispatch_from;
380  	/**
381  	 * @dispatch_busy: Number used by blk_mq_update_dispatch_busy() to
382  	 * decide if the hw_queue is busy using Exponential Weighted Moving
383  	 * Average algorithm.
384  	 */
385  	unsigned int		dispatch_busy;
386  
387  	/** @type: HCTX_TYPE_* flags. Type of hardware queue. */
388  	unsigned short		type;
389  	/** @nr_ctx: Number of software queues. */
390  	unsigned short		nr_ctx;
391  	/** @ctxs: Array of software queues. */
392  	struct blk_mq_ctx	**ctxs;
393  
394  	/** @dispatch_wait_lock: Lock for dispatch_wait queue. */
395  	spinlock_t		dispatch_wait_lock;
396  	/**
397  	 * @dispatch_wait: Waitqueue to put requests when there is no tag
398  	 * available at the moment, to wait for another try in the future.
399  	 */
400  	wait_queue_entry_t	dispatch_wait;
401  
402  	/**
403  	 * @wait_index: Index of next available dispatch_wait queue to insert
404  	 * requests.
405  	 */
406  	atomic_t		wait_index;
407  
408  	/**
409  	 * @tags: Tags owned by the block driver. A tag at this set is only
410  	 * assigned when a request is dispatched from a hardware queue.
411  	 */
412  	struct blk_mq_tags	*tags;
413  	/**
414  	 * @sched_tags: Tags owned by I/O scheduler. If there is an I/O
415  	 * scheduler associated with a request queue, a tag is assigned when
416  	 * that request is allocated. Else, this member is not used.
417  	 */
418  	struct blk_mq_tags	*sched_tags;
419  
420  	/** @numa_node: NUMA node the storage adapter has been connected to. */
421  	unsigned int		numa_node;
422  	/** @queue_num: Index of this hardware queue. */
423  	unsigned int		queue_num;
424  
425  	/**
426  	 * @nr_active: Number of active requests. Only used when a tag set is
427  	 * shared across request queues.
428  	 */
429  	atomic_t		nr_active;
430  
431  	/** @cpuhp_online: List to store request if CPU is going to die */
432  	struct hlist_node	cpuhp_online;
433  	/** @cpuhp_dead: List to store request if some CPU die. */
434  	struct hlist_node	cpuhp_dead;
435  	/** @kobj: Kernel object for sysfs. */
436  	struct kobject		kobj;
437  
438  #ifdef CONFIG_BLK_DEBUG_FS
439  	/**
440  	 * @debugfs_dir: debugfs directory for this hardware queue. Named
441  	 * as cpu<cpu_number>.
442  	 */
443  	struct dentry		*debugfs_dir;
444  	/** @sched_debugfs_dir:	debugfs directory for the scheduler. */
445  	struct dentry		*sched_debugfs_dir;
446  #endif
447  
448  	/**
449  	 * @hctx_list: if this hctx is not in use, this is an entry in
450  	 * q->unused_hctx_list.
451  	 */
452  	struct list_head	hctx_list;
453  };
454  
455  /**
456   * struct blk_mq_queue_map - Map software queues to hardware queues
457   * @mq_map:       CPU ID to hardware queue index map. This is an array
458   *	with nr_cpu_ids elements. Each element has a value in the range
459   *	[@queue_offset, @queue_offset + @nr_queues).
460   * @nr_queues:    Number of hardware queues to map CPU IDs onto.
461   * @queue_offset: First hardware queue to map onto. Used by the PCIe NVMe
462   *	driver to map each hardware queue type (enum hctx_type) onto a distinct
463   *	set of hardware queues.
464   */
465  struct blk_mq_queue_map {
466  	unsigned int *mq_map;
467  	unsigned int nr_queues;
468  	unsigned int queue_offset;
469  };
470  
471  /**
472   * enum hctx_type - Type of hardware queue
473   * @HCTX_TYPE_DEFAULT:	All I/O not otherwise accounted for.
474   * @HCTX_TYPE_READ:	Just for READ I/O.
475   * @HCTX_TYPE_POLL:	Polled I/O of any kind.
476   * @HCTX_MAX_TYPES:	Number of types of hctx.
477   */
478  enum hctx_type {
479  	HCTX_TYPE_DEFAULT,
480  	HCTX_TYPE_READ,
481  	HCTX_TYPE_POLL,
482  
483  	HCTX_MAX_TYPES,
484  };
485  
486  /**
487   * struct blk_mq_tag_set - tag set that can be shared between request queues
488   * @ops:	   Pointers to functions that implement block driver behavior.
489   * @map:	   One or more ctx -> hctx mappings. One map exists for each
490   *		   hardware queue type (enum hctx_type) that the driver wishes
491   *		   to support. There are no restrictions on maps being of the
492   *		   same size, and it's perfectly legal to share maps between
493   *		   types.
494   * @nr_maps:	   Number of elements in the @map array. A number in the range
495   *		   [1, HCTX_MAX_TYPES].
496   * @nr_hw_queues:  Number of hardware queues supported by the block driver that
497   *		   owns this data structure.
498   * @queue_depth:   Number of tags per hardware queue, reserved tags included.
499   * @reserved_tags: Number of tags to set aside for BLK_MQ_REQ_RESERVED tag
500   *		   allocations.
501   * @cmd_size:	   Number of additional bytes to allocate per request. The block
502   *		   driver owns these additional bytes.
503   * @numa_node:	   NUMA node the storage adapter has been connected to.
504   * @timeout:	   Request processing timeout in jiffies.
505   * @flags:	   Zero or more BLK_MQ_F_* flags.
506   * @driver_data:   Pointer to data owned by the block driver that created this
507   *		   tag set.
508   * @tags:	   Tag sets. One tag set per hardware queue. Has @nr_hw_queues
509   *		   elements.
510   * @shared_tags:
511   *		   Shared set of tags. Has @nr_hw_queues elements. If set,
512   *		   shared by all @tags.
513   * @tag_list_lock: Serializes tag_list accesses.
514   * @tag_list:	   List of the request queues that use this tag set. See also
515   *		   request_queue.tag_set_list.
516   * @srcu:	   Use as lock when type of the request queue is blocking
517   *		   (BLK_MQ_F_BLOCKING).
518   */
519  struct blk_mq_tag_set {
520  	const struct blk_mq_ops	*ops;
521  	struct blk_mq_queue_map	map[HCTX_MAX_TYPES];
522  	unsigned int		nr_maps;
523  	unsigned int		nr_hw_queues;
524  	unsigned int		queue_depth;
525  	unsigned int		reserved_tags;
526  	unsigned int		cmd_size;
527  	int			numa_node;
528  	unsigned int		timeout;
529  	unsigned int		flags;
530  	void			*driver_data;
531  
532  	struct blk_mq_tags	**tags;
533  
534  	struct blk_mq_tags	*shared_tags;
535  
536  	struct mutex		tag_list_lock;
537  	struct list_head	tag_list;
538  	struct srcu_struct	*srcu;
539  };
540  
541  /**
542   * struct blk_mq_queue_data - Data about a request inserted in a queue
543   *
544   * @rq:   Request pointer.
545   * @last: If it is the last request in the queue.
546   */
547  struct blk_mq_queue_data {
548  	struct request *rq;
549  	bool last;
550  };
551  
552  typedef bool (busy_tag_iter_fn)(struct request *, void *);
553  
554  /**
555   * struct blk_mq_ops - Callback functions that implements block driver
556   * behaviour.
557   */
558  struct blk_mq_ops {
559  	/**
560  	 * @queue_rq: Queue a new request from block IO.
561  	 */
562  	blk_status_t (*queue_rq)(struct blk_mq_hw_ctx *,
563  				 const struct blk_mq_queue_data *);
564  
565  	/**
566  	 * @commit_rqs: If a driver uses bd->last to judge when to submit
567  	 * requests to hardware, it must define this function. In case of errors
568  	 * that make us stop issuing further requests, this hook serves the
569  	 * purpose of kicking the hardware (which the last request otherwise
570  	 * would have done).
571  	 */
572  	void (*commit_rqs)(struct blk_mq_hw_ctx *);
573  
574  	/**
575  	 * @queue_rqs: Queue a list of new requests. Driver is guaranteed
576  	 * that each request belongs to the same queue. If the driver doesn't
577  	 * empty the @rqlist completely, then the rest will be queued
578  	 * individually by the block layer upon return.
579  	 */
580  	void (*queue_rqs)(struct request **rqlist);
581  
582  	/**
583  	 * @get_budget: Reserve budget before queue request, once .queue_rq is
584  	 * run, it is driver's responsibility to release the
585  	 * reserved budget. Also we have to handle failure case
586  	 * of .get_budget for avoiding I/O deadlock.
587  	 */
588  	int (*get_budget)(struct request_queue *);
589  
590  	/**
591  	 * @put_budget: Release the reserved budget.
592  	 */
593  	void (*put_budget)(struct request_queue *, int);
594  
595  	/**
596  	 * @set_rq_budget_token: store rq's budget token
597  	 */
598  	void (*set_rq_budget_token)(struct request *, int);
599  	/**
600  	 * @get_rq_budget_token: retrieve rq's budget token
601  	 */
602  	int (*get_rq_budget_token)(struct request *);
603  
604  	/**
605  	 * @timeout: Called on request timeout.
606  	 */
607  	enum blk_eh_timer_return (*timeout)(struct request *);
608  
609  	/**
610  	 * @poll: Called to poll for completion of a specific tag.
611  	 */
612  	int (*poll)(struct blk_mq_hw_ctx *, struct io_comp_batch *);
613  
614  	/**
615  	 * @complete: Mark the request as complete.
616  	 */
617  	void (*complete)(struct request *);
618  
619  	/**
620  	 * @init_hctx: Called when the block layer side of a hardware queue has
621  	 * been set up, allowing the driver to allocate/init matching
622  	 * structures.
623  	 */
624  	int (*init_hctx)(struct blk_mq_hw_ctx *, void *, unsigned int);
625  	/**
626  	 * @exit_hctx: Ditto for exit/teardown.
627  	 */
628  	void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);
629  
630  	/**
631  	 * @init_request: Called for every command allocated by the block layer
632  	 * to allow the driver to set up driver specific data.
633  	 *
634  	 * Tag greater than or equal to queue_depth is for setting up
635  	 * flush request.
636  	 */
637  	int (*init_request)(struct blk_mq_tag_set *set, struct request *,
638  			    unsigned int, unsigned int);
639  	/**
640  	 * @exit_request: Ditto for exit/teardown.
641  	 */
642  	void (*exit_request)(struct blk_mq_tag_set *set, struct request *,
643  			     unsigned int);
644  
645  	/**
646  	 * @cleanup_rq: Called before freeing one request which isn't completed
647  	 * yet, and usually for freeing the driver private data.
648  	 */
649  	void (*cleanup_rq)(struct request *);
650  
651  	/**
652  	 * @busy: If set, returns whether or not this queue currently is busy.
653  	 */
654  	bool (*busy)(struct request_queue *);
655  
656  	/**
657  	 * @map_queues: This allows drivers specify their own queue mapping by
658  	 * overriding the setup-time function that builds the mq_map.
659  	 */
660  	void (*map_queues)(struct blk_mq_tag_set *set);
661  
662  #ifdef CONFIG_BLK_DEBUG_FS
663  	/**
664  	 * @show_rq: Used by the debugfs implementation to show driver-specific
665  	 * information about a request.
666  	 */
667  	void (*show_rq)(struct seq_file *m, struct request *rq);
668  #endif
669  };
670  
671  /* Keep hctx_flag_name[] in sync with the definitions below */
672  enum {
673  	BLK_MQ_F_SHOULD_MERGE	= 1 << 0,
674  	BLK_MQ_F_TAG_QUEUE_SHARED = 1 << 1,
675  	/*
676  	 * Set when this device requires underlying blk-mq device for
677  	 * completing IO:
678  	 */
679  	BLK_MQ_F_STACKING	= 1 << 2,
680  	BLK_MQ_F_TAG_HCTX_SHARED = 1 << 3,
681  	BLK_MQ_F_BLOCKING	= 1 << 4,
682  	/* Do not allow an I/O scheduler to be configured. */
683  	BLK_MQ_F_NO_SCHED	= 1 << 5,
684  
685  	/*
686  	 * Select 'none' during queue registration in case of a single hwq
687  	 * or shared hwqs instead of 'mq-deadline'.
688  	 */
689  	BLK_MQ_F_NO_SCHED_BY_DEFAULT	= 1 << 6,
690  	BLK_MQ_F_ALLOC_POLICY_START_BIT = 7,
691  	BLK_MQ_F_ALLOC_POLICY_BITS = 1,
692  };
693  #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \
694  	((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \
695  		((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1))
696  #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \
697  	((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \
698  		<< BLK_MQ_F_ALLOC_POLICY_START_BIT)
699  
700  #define BLK_MQ_MAX_DEPTH	(10240)
701  #define BLK_MQ_NO_HCTX_IDX	(-1U)
702  
703  enum {
704  	/* Keep hctx_state_name[] in sync with the definitions below */
705  	BLK_MQ_S_STOPPED,
706  	BLK_MQ_S_TAG_ACTIVE,
707  	BLK_MQ_S_SCHED_RESTART,
708  	/* hw queue is inactive after all its CPUs become offline */
709  	BLK_MQ_S_INACTIVE,
710  	BLK_MQ_S_MAX
711  };
712  
713  struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set,
714  		struct queue_limits *lim, void *queuedata,
715  		struct lock_class_key *lkclass);
716  #define blk_mq_alloc_disk(set, lim, queuedata)				\
717  ({									\
718  	static struct lock_class_key __key;				\
719  									\
720  	__blk_mq_alloc_disk(set, lim, queuedata, &__key);		\
721  })
722  struct gendisk *blk_mq_alloc_disk_for_queue(struct request_queue *q,
723  		struct lock_class_key *lkclass);
724  struct request_queue *blk_mq_alloc_queue(struct blk_mq_tag_set *set,
725  		struct queue_limits *lim, void *queuedata);
726  int blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
727  		struct request_queue *q);
728  void blk_mq_destroy_queue(struct request_queue *);
729  
730  int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set);
731  int blk_mq_alloc_sq_tag_set(struct blk_mq_tag_set *set,
732  		const struct blk_mq_ops *ops, unsigned int queue_depth,
733  		unsigned int set_flags);
734  void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
735  
736  void blk_mq_free_request(struct request *rq);
737  int blk_rq_poll(struct request *rq, struct io_comp_batch *iob,
738  		unsigned int poll_flags);
739  
740  bool blk_mq_queue_inflight(struct request_queue *q);
741  
742  enum {
743  	/* return when out of requests */
744  	BLK_MQ_REQ_NOWAIT	= (__force blk_mq_req_flags_t)(1 << 0),
745  	/* allocate from reserved pool */
746  	BLK_MQ_REQ_RESERVED	= (__force blk_mq_req_flags_t)(1 << 1),
747  	/* set RQF_PM */
748  	BLK_MQ_REQ_PM		= (__force blk_mq_req_flags_t)(1 << 2),
749  };
750  
751  struct request *blk_mq_alloc_request(struct request_queue *q, blk_opf_t opf,
752  		blk_mq_req_flags_t flags);
753  struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
754  		blk_opf_t opf, blk_mq_req_flags_t flags,
755  		unsigned int hctx_idx);
756  
757  /*
758   * Tag address space map.
759   */
760  struct blk_mq_tags {
761  	unsigned int nr_tags;
762  	unsigned int nr_reserved_tags;
763  	unsigned int active_queues;
764  
765  	struct sbitmap_queue bitmap_tags;
766  	struct sbitmap_queue breserved_tags;
767  
768  	struct request **rqs;
769  	struct request **static_rqs;
770  	struct list_head page_list;
771  
772  	/*
773  	 * used to clear request reference in rqs[] before freeing one
774  	 * request pool
775  	 */
776  	spinlock_t lock;
777  };
778  
blk_mq_tag_to_rq(struct blk_mq_tags * tags,unsigned int tag)779  static inline struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags,
780  					       unsigned int tag)
781  {
782  	if (tag < tags->nr_tags) {
783  		prefetch(tags->rqs[tag]);
784  		return tags->rqs[tag];
785  	}
786  
787  	return NULL;
788  }
789  
790  enum {
791  	BLK_MQ_UNIQUE_TAG_BITS = 16,
792  	BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1,
793  };
794  
795  u32 blk_mq_unique_tag(struct request *rq);
796  
blk_mq_unique_tag_to_hwq(u32 unique_tag)797  static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag)
798  {
799  	return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS;
800  }
801  
blk_mq_unique_tag_to_tag(u32 unique_tag)802  static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag)
803  {
804  	return unique_tag & BLK_MQ_UNIQUE_TAG_MASK;
805  }
806  
807  /**
808   * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
809   * @rq: target request.
810   */
blk_mq_rq_state(struct request * rq)811  static inline enum mq_rq_state blk_mq_rq_state(struct request *rq)
812  {
813  	return READ_ONCE(rq->state);
814  }
815  
blk_mq_request_started(struct request * rq)816  static inline int blk_mq_request_started(struct request *rq)
817  {
818  	return blk_mq_rq_state(rq) != MQ_RQ_IDLE;
819  }
820  
blk_mq_request_completed(struct request * rq)821  static inline int blk_mq_request_completed(struct request *rq)
822  {
823  	return blk_mq_rq_state(rq) == MQ_RQ_COMPLETE;
824  }
825  
826  /*
827   *
828   * Set the state to complete when completing a request from inside ->queue_rq.
829   * This is used by drivers that want to ensure special complete actions that
830   * need access to the request are called on failure, e.g. by nvme for
831   * multipathing.
832   */
blk_mq_set_request_complete(struct request * rq)833  static inline void blk_mq_set_request_complete(struct request *rq)
834  {
835  	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
836  }
837  
838  /*
839   * Complete the request directly instead of deferring it to softirq or
840   * completing it another CPU. Useful in preemptible instead of an interrupt.
841   */
blk_mq_complete_request_direct(struct request * rq,void (* complete)(struct request * rq))842  static inline void blk_mq_complete_request_direct(struct request *rq,
843  		   void (*complete)(struct request *rq))
844  {
845  	WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
846  	complete(rq);
847  }
848  
849  void blk_mq_start_request(struct request *rq);
850  void blk_mq_end_request(struct request *rq, blk_status_t error);
851  void __blk_mq_end_request(struct request *rq, blk_status_t error);
852  void blk_mq_end_request_batch(struct io_comp_batch *ib);
853  
854  /*
855   * Only need start/end time stamping if we have iostat or
856   * blk stats enabled, or using an IO scheduler.
857   */
blk_mq_need_time_stamp(struct request * rq)858  static inline bool blk_mq_need_time_stamp(struct request *rq)
859  {
860  	/*
861  	 * passthrough io doesn't use iostat accounting, cgroup stats
862  	 * and io scheduler functionalities.
863  	 */
864  	if (blk_rq_is_passthrough(rq))
865  		return false;
866  	return (rq->rq_flags & (RQF_IO_STAT | RQF_STATS | RQF_USE_SCHED));
867  }
868  
blk_mq_is_reserved_rq(struct request * rq)869  static inline bool blk_mq_is_reserved_rq(struct request *rq)
870  {
871  	return rq->rq_flags & RQF_RESV;
872  }
873  
874  /*
875   * Batched completions only work when there is no I/O error and no special
876   * ->end_io handler.
877   */
blk_mq_add_to_batch(struct request * req,struct io_comp_batch * iob,int ioerror,void (* complete)(struct io_comp_batch *))878  static inline bool blk_mq_add_to_batch(struct request *req,
879  				       struct io_comp_batch *iob, int ioerror,
880  				       void (*complete)(struct io_comp_batch *))
881  {
882  	/*
883  	 * blk_mq_end_request_batch() can't end request allocated from
884  	 * sched tags
885  	 */
886  	if (!iob || (req->rq_flags & RQF_SCHED_TAGS) || ioerror ||
887  			(req->end_io && !blk_rq_is_passthrough(req)))
888  		return false;
889  
890  	if (!iob->complete)
891  		iob->complete = complete;
892  	else if (iob->complete != complete)
893  		return false;
894  	iob->need_ts |= blk_mq_need_time_stamp(req);
895  	rq_list_add(&iob->req_list, req);
896  	return true;
897  }
898  
899  void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list);
900  void blk_mq_kick_requeue_list(struct request_queue *q);
901  void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs);
902  void blk_mq_complete_request(struct request *rq);
903  bool blk_mq_complete_request_remote(struct request *rq);
904  void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
905  void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx);
906  void blk_mq_stop_hw_queues(struct request_queue *q);
907  void blk_mq_start_hw_queues(struct request_queue *q);
908  void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
909  void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
910  void blk_mq_quiesce_queue(struct request_queue *q);
911  void blk_mq_wait_quiesce_done(struct blk_mq_tag_set *set);
912  void blk_mq_quiesce_tagset(struct blk_mq_tag_set *set);
913  void blk_mq_unquiesce_tagset(struct blk_mq_tag_set *set);
914  void blk_mq_unquiesce_queue(struct request_queue *q);
915  void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
916  void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
917  void blk_mq_run_hw_queues(struct request_queue *q, bool async);
918  void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs);
919  void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
920  		busy_tag_iter_fn *fn, void *priv);
921  void blk_mq_tagset_wait_completed_request(struct blk_mq_tag_set *tagset);
922  void blk_mq_freeze_queue(struct request_queue *q);
923  void blk_mq_unfreeze_queue(struct request_queue *q);
924  void blk_freeze_queue_start(struct request_queue *q);
925  void blk_mq_freeze_queue_wait(struct request_queue *q);
926  int blk_mq_freeze_queue_wait_timeout(struct request_queue *q,
927  				     unsigned long timeout);
928  
929  void blk_mq_map_queues(struct blk_mq_queue_map *qmap);
930  void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues);
931  
932  void blk_mq_quiesce_queue_nowait(struct request_queue *q);
933  
934  unsigned int blk_mq_rq_cpu(struct request *rq);
935  
936  bool __blk_should_fake_timeout(struct request_queue *q);
blk_should_fake_timeout(struct request_queue * q)937  static inline bool blk_should_fake_timeout(struct request_queue *q)
938  {
939  	if (IS_ENABLED(CONFIG_FAIL_IO_TIMEOUT) &&
940  	    test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags))
941  		return __blk_should_fake_timeout(q);
942  	return false;
943  }
944  
945  /**
946   * blk_mq_rq_from_pdu - cast a PDU to a request
947   * @pdu: the PDU (Protocol Data Unit) to be casted
948   *
949   * Return: request
950   *
951   * Driver command data is immediately after the request. So subtract request
952   * size to get back to the original request.
953   */
blk_mq_rq_from_pdu(void * pdu)954  static inline struct request *blk_mq_rq_from_pdu(void *pdu)
955  {
956  	return pdu - sizeof(struct request);
957  }
958  
959  /**
960   * blk_mq_rq_to_pdu - cast a request to a PDU
961   * @rq: the request to be casted
962   *
963   * Return: pointer to the PDU
964   *
965   * Driver command data is immediately after the request. So add request to get
966   * the PDU.
967   */
blk_mq_rq_to_pdu(struct request * rq)968  static inline void *blk_mq_rq_to_pdu(struct request *rq)
969  {
970  	return rq + 1;
971  }
972  
973  #define queue_for_each_hw_ctx(q, hctx, i)				\
974  	xa_for_each(&(q)->hctx_table, (i), (hctx))
975  
976  #define hctx_for_each_ctx(hctx, ctx, i)					\
977  	for ((i) = 0; (i) < (hctx)->nr_ctx &&				\
978  	     ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++)
979  
blk_mq_cleanup_rq(struct request * rq)980  static inline void blk_mq_cleanup_rq(struct request *rq)
981  {
982  	if (rq->q->mq_ops->cleanup_rq)
983  		rq->q->mq_ops->cleanup_rq(rq);
984  }
985  
blk_rq_bio_prep(struct request * rq,struct bio * bio,unsigned int nr_segs)986  static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
987  		unsigned int nr_segs)
988  {
989  	rq->nr_phys_segments = nr_segs;
990  	rq->__data_len = bio->bi_iter.bi_size;
991  	rq->bio = rq->biotail = bio;
992  	rq->ioprio = bio_prio(bio);
993  }
994  
995  void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx,
996  		struct lock_class_key *key);
997  
rq_is_sync(struct request * rq)998  static inline bool rq_is_sync(struct request *rq)
999  {
1000  	return op_is_sync(rq->cmd_flags);
1001  }
1002  
1003  void blk_rq_init(struct request_queue *q, struct request *rq);
1004  int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
1005  		struct bio_set *bs, gfp_t gfp_mask,
1006  		int (*bio_ctr)(struct bio *, struct bio *, void *), void *data);
1007  void blk_rq_unprep_clone(struct request *rq);
1008  blk_status_t blk_insert_cloned_request(struct request *rq);
1009  
1010  struct rq_map_data {
1011  	struct page **pages;
1012  	unsigned long offset;
1013  	unsigned short page_order;
1014  	unsigned short nr_entries;
1015  	bool null_mapped;
1016  	bool from_user;
1017  };
1018  
1019  int blk_rq_map_user(struct request_queue *, struct request *,
1020  		struct rq_map_data *, void __user *, unsigned long, gfp_t);
1021  int blk_rq_map_user_io(struct request *, struct rq_map_data *,
1022  		void __user *, unsigned long, gfp_t, bool, int, bool, int);
1023  int blk_rq_map_user_iov(struct request_queue *, struct request *,
1024  		struct rq_map_data *, const struct iov_iter *, gfp_t);
1025  int blk_rq_unmap_user(struct bio *);
1026  int blk_rq_map_kern(struct request_queue *, struct request *, void *,
1027  		unsigned int, gfp_t);
1028  int blk_rq_append_bio(struct request *rq, struct bio *bio);
1029  void blk_execute_rq_nowait(struct request *rq, bool at_head);
1030  blk_status_t blk_execute_rq(struct request *rq, bool at_head);
1031  bool blk_rq_is_poll(struct request *rq);
1032  
1033  struct req_iterator {
1034  	struct bvec_iter iter;
1035  	struct bio *bio;
1036  };
1037  
1038  #define __rq_for_each_bio(_bio, rq)	\
1039  	if ((rq->bio))			\
1040  		for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
1041  
1042  #define rq_for_each_segment(bvl, _rq, _iter)			\
1043  	__rq_for_each_bio(_iter.bio, _rq)			\
1044  		bio_for_each_segment(bvl, _iter.bio, _iter.iter)
1045  
1046  #define rq_for_each_bvec(bvl, _rq, _iter)			\
1047  	__rq_for_each_bio(_iter.bio, _rq)			\
1048  		bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
1049  
1050  #define rq_iter_last(bvec, _iter)				\
1051  		(_iter.bio->bi_next == NULL &&			\
1052  		 bio_iter_last(bvec, _iter.iter))
1053  
1054  /*
1055   * blk_rq_pos()			: the current sector
1056   * blk_rq_bytes()		: bytes left in the entire request
1057   * blk_rq_cur_bytes()		: bytes left in the current segment
1058   * blk_rq_sectors()		: sectors left in the entire request
1059   * blk_rq_cur_sectors()		: sectors left in the current segment
1060   * blk_rq_stats_sectors()	: sectors of the entire request used for stats
1061   */
blk_rq_pos(const struct request * rq)1062  static inline sector_t blk_rq_pos(const struct request *rq)
1063  {
1064  	return rq->__sector;
1065  }
1066  
blk_rq_bytes(const struct request * rq)1067  static inline unsigned int blk_rq_bytes(const struct request *rq)
1068  {
1069  	return rq->__data_len;
1070  }
1071  
blk_rq_cur_bytes(const struct request * rq)1072  static inline int blk_rq_cur_bytes(const struct request *rq)
1073  {
1074  	if (!rq->bio)
1075  		return 0;
1076  	if (!bio_has_data(rq->bio))	/* dataless requests such as discard */
1077  		return rq->bio->bi_iter.bi_size;
1078  	return bio_iovec(rq->bio).bv_len;
1079  }
1080  
blk_rq_sectors(const struct request * rq)1081  static inline unsigned int blk_rq_sectors(const struct request *rq)
1082  {
1083  	return blk_rq_bytes(rq) >> SECTOR_SHIFT;
1084  }
1085  
blk_rq_cur_sectors(const struct request * rq)1086  static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
1087  {
1088  	return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
1089  }
1090  
blk_rq_stats_sectors(const struct request * rq)1091  static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
1092  {
1093  	return rq->stats_sectors;
1094  }
1095  
1096  /*
1097   * Some commands like WRITE SAME have a payload or data transfer size which
1098   * is different from the size of the request.  Any driver that supports such
1099   * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1100   * calculate the data transfer size.
1101   */
blk_rq_payload_bytes(struct request * rq)1102  static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1103  {
1104  	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1105  		return rq->special_vec.bv_len;
1106  	return blk_rq_bytes(rq);
1107  }
1108  
1109  /*
1110   * Return the first full biovec in the request.  The caller needs to check that
1111   * there are any bvecs before calling this helper.
1112   */
req_bvec(struct request * rq)1113  static inline struct bio_vec req_bvec(struct request *rq)
1114  {
1115  	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1116  		return rq->special_vec;
1117  	return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
1118  }
1119  
blk_rq_count_bios(struct request * rq)1120  static inline unsigned int blk_rq_count_bios(struct request *rq)
1121  {
1122  	unsigned int nr_bios = 0;
1123  	struct bio *bio;
1124  
1125  	__rq_for_each_bio(bio, rq)
1126  		nr_bios++;
1127  
1128  	return nr_bios;
1129  }
1130  
1131  void blk_steal_bios(struct bio_list *list, struct request *rq);
1132  
1133  /*
1134   * Request completion related functions.
1135   *
1136   * blk_update_request() completes given number of bytes and updates
1137   * the request without completing it.
1138   */
1139  bool blk_update_request(struct request *rq, blk_status_t error,
1140  			       unsigned int nr_bytes);
1141  void blk_abort_request(struct request *);
1142  
1143  /*
1144   * Number of physical segments as sent to the device.
1145   *
1146   * Normally this is the number of discontiguous data segments sent by the
1147   * submitter.  But for data-less command like discard we might have no
1148   * actual data segments submitted, but the driver might have to add it's
1149   * own special payload.  In that case we still return 1 here so that this
1150   * special payload will be mapped.
1151   */
blk_rq_nr_phys_segments(struct request * rq)1152  static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1153  {
1154  	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1155  		return 1;
1156  	return rq->nr_phys_segments;
1157  }
1158  
1159  /*
1160   * Number of discard segments (or ranges) the driver needs to fill in.
1161   * Each discard bio merged into a request is counted as one segment.
1162   */
blk_rq_nr_discard_segments(struct request * rq)1163  static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1164  {
1165  	return max_t(unsigned short, rq->nr_phys_segments, 1);
1166  }
1167  
1168  int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
1169  		struct scatterlist *sglist, struct scatterlist **last_sg);
blk_rq_map_sg(struct request_queue * q,struct request * rq,struct scatterlist * sglist)1170  static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
1171  		struct scatterlist *sglist)
1172  {
1173  	struct scatterlist *last_sg = NULL;
1174  
1175  	return __blk_rq_map_sg(q, rq, sglist, &last_sg);
1176  }
1177  void blk_dump_rq_flags(struct request *, char *);
1178  
1179  #endif /* BLK_MQ_H */
1180