blob: 10bfdfb494faf4035f8be143f1cf6e47e32fe50c [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef INT_BLK_MQ_H
#define INT_BLK_MQ_H
#include "blk-stat.h"
#include "blk-mq-tag.h"
struct blk_mq_tag_set;
struct blk_mq_ctxs {
struct kobject kobj;
struct blk_mq_ctx __percpu *queue_ctx;
* struct blk_mq_ctx - State for a software queue facing the submitting CPUs
struct blk_mq_ctx {
struct {
spinlock_t lock;
struct list_head rq_lists[HCTX_MAX_TYPES];
} ____cacheline_aligned_in_smp;
unsigned int cpu;
unsigned short index_hw[HCTX_MAX_TYPES];
struct blk_mq_hw_ctx *hctxs[HCTX_MAX_TYPES];
/* incremented at dispatch time */
unsigned long rq_dispatched[2];
unsigned long rq_merged;
/* incremented at completion time */
unsigned long ____cacheline_aligned_in_smp rq_completed[2];
struct request_queue *queue;
struct blk_mq_ctxs *ctxs;
struct kobject kobj;
} ____cacheline_aligned_in_smp;
void blk_mq_exit_queue(struct request_queue *q);
int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
void blk_mq_wake_waiters(struct request_queue *q);
bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
bool kick_requeue_list);
void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
bool blk_mq_get_driver_tag(struct request *rq);
struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *start);
* Internal helpers for allocating/freeing the request map
void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
unsigned int hctx_idx);
void blk_mq_free_rq_map(struct blk_mq_tags *tags);
struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
unsigned int hctx_idx,
unsigned int nr_tags,
unsigned int reserved_tags);
int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
unsigned int hctx_idx, unsigned int depth);
* Internal helpers for request insertion into sw queues
void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
bool at_head);
void blk_mq_request_bypass_insert(struct request *rq, bool at_head,
bool run_queue);
void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
struct list_head *list);
/* Used by blk_insert_cloned_request() to issue request directly */
blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last);
void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
struct list_head *list);
* CPU -> queue mappings
extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
* blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
* @q: request queue
* @type: the hctx type index
* @cpu: CPU
static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
enum hctx_type type,
unsigned int cpu)
return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]];
* blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
* @q: request queue
* @flags: request command flags
* @cpu: cpu ctx
static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
unsigned int flags,
struct blk_mq_ctx *ctx)
enum hctx_type type = HCTX_TYPE_DEFAULT;
* The caller ensure that if REQ_HIPRI, poll must be enabled.
if (flags & REQ_HIPRI)
else if ((flags & REQ_OP_MASK) == REQ_OP_READ)
return ctx->hctxs[type];
* sysfs helpers
extern void blk_mq_sysfs_init(struct request_queue *q);
extern void blk_mq_sysfs_deinit(struct request_queue *q);
extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
extern int blk_mq_sysfs_register(struct request_queue *q);
extern void blk_mq_sysfs_unregister(struct request_queue *q);
extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
void blk_mq_release(struct request_queue *q);
static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
unsigned int cpu)
return per_cpu_ptr(q->queue_ctx, cpu);
* This assumes per-cpu software queueing queues. They could be per-node
* as well, for instance. For now this is hardcoded as-is. Note that we don't
* care about preemption, since we know the ctx's are persistent. This does
* mean that we can't rely on ctx always matching the currently running CPU.
static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
return __blk_mq_get_ctx(q, raw_smp_processor_id());
struct blk_mq_alloc_data {
/* input parameter */
struct request_queue *q;
blk_mq_req_flags_t flags;
unsigned int shallow_depth;
unsigned int cmd_flags;
/* input & output parameter */
struct blk_mq_ctx *ctx;
struct blk_mq_hw_ctx *hctx;
static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
if (data->flags & BLK_MQ_REQ_INTERNAL)
return data->hctx->sched_tags;
return data->hctx->tags;
static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
return hctx->nr_ctx && hctx->tags;
unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
unsigned int inflight[2]);
static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
struct request_queue *q = hctx->queue;
if (q->mq_ops->put_budget)
static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
struct request_queue *q = hctx->queue;
if (q->mq_ops->get_budget)
return q->mq_ops->get_budget(hctx);
return true;
static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
struct request *rq)
blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
rq->tag = -1;
if (rq->rq_flags & RQF_MQ_INFLIGHT) {
rq->rq_flags &= ~RQF_MQ_INFLIGHT;
static inline void blk_mq_put_driver_tag(struct request *rq)
if (rq->tag == -1 || rq->internal_tag == -1)
__blk_mq_put_driver_tag(rq->mq_hctx, rq);
static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
int cpu;
qmap->mq_map[cpu] = 0;
* blk_mq_plug() - Get caller context plug
* @q: request queue
* @bio : the bio being submitted by the caller context
* Plugging, by design, may delay the insertion of BIOs into the elevator in
* order to increase BIO merging opportunities. This however can cause BIO
* insertion order to change from the order in which submit_bio() is being
* executed in the case of multiple contexts concurrently issuing BIOs to a
* device, even if these context are synchronized to tightly control BIO issuing
* order. While this is not a problem with regular block devices, this ordering
* change can cause write BIO failures with zoned block devices as these
* require sequential write patterns to zones. Prevent this from happening by
* ignoring the plug state of a BIO issuing context if the target request queue
* is for a zoned block device and the BIO to plug is a write operation.
* Return current->plug if the bio can be plugged and NULL otherwise
static inline struct blk_plug *blk_mq_plug(struct request_queue *q,
struct bio *bio)
* For regular block devices or read operations, use the context plug
* which may be NULL if blk_start_plug() was not executed.
if (!blk_queue_is_zoned(q) || !op_is_write(bio_op(bio)))
return current->plug;
/* Zoned block device write operation case: do not plug the BIO */
return NULL;