Now that we have a template, expand on the kdoc form for the request_queue data structure with documentation from the rest of the members, *only* for information we already had.
This does not add any new documentation. This just shifts documentation to kdoc form. Signed-off-by: Luis Chamberlain <[email protected]> --- include/linux/blkdev.h | 139 ++++++++++++----------------------------- 1 file changed, 40 insertions(+), 99 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index ea319c2b0593..d30bfef893b9 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -396,8 +396,38 @@ static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev, /** * struct request_queue - block device driver request queue + * @queue_ctx: software queue context + * @queue_hw_ctx: hw dispatch queues + * @queuedata: the queue owner gets to use this for whatever they like. + * ll_rw_blk doesn't touch it. + * @queue_flags: various queue flags, see %QUEUE_* below + * @pm_only: Number of contexts that have called blk_set_pm_only(). If this + * counter is above zero then only %RQF_PM and %RQF_PREEMPT requests are + * processed. + * @id: ida allocated id for this queue. Used to index queues from ioctx. + * @bounce_gfp: queue needs bounce pages for pages above this limit + * @kobj: queue kobject + * @mq_kobj: mq queue kobject + * @nr_requests: maximum number of of requests + * @ksm: Inline crypto capabilities + * @nr_zones: + * @nr_zones: total number of zones of the device. This is always 0 for regular + * block devices. + * @conv_zones_bitmap: bitmap of nr_zones bits which indicates if a zone + * is conventional (bit set) or sequential (bit clear). + * @seq_zones_wlock: bitmap of nr_zones bits which indicates if a zone + * is write locked, that is, if a write request targeting the zone was + * dispatched. + * @debugfs_mutex: used to protect access to the @ebugfs_dir * @debugfs_mutex: used to protect access to the @debugfs_dir * @blk_trace: used by blktrace to keep track of setup / tracing + * @fq: for flush operations + * @td: throttle data + * @unused_hctx_list: list used for reusing dead hctx instance in case of + * updating nr_hw_queues. + * @unused_hctx_lock: used to protect the @unused_hctx_list + * @mq_freeze_lock: protects concurrent access to q_usage_counter by + * percpu_ref_kill() and percpu_ref_reinit(). * @debugfs_dir: directory created to place debugfs information. This is always * created for make_request and request-based block drivers upon * initialization. blktrace requires for this directory to be created, @@ -413,67 +443,35 @@ static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev, * o custom solutions such as scsi-generic * * All partitions share the same request_queue data structure. + * + * Zoned block device dispatch control is managed by the fields @nr_zones, + * @conv_zones_bitmap and @seq_zones_wlock. These fields are fields are + * initialized by the low level device driver (e.g. scsi/sd.c). Stacking + * drivers (device mappers) may or may not initialize these fields. + * Reads of this information must be protected with blk_queue_enter() / + * blk_queue_exit(). Modifying this information is only allowed while + * no requests are being processed. See also blk_mq_freeze_queue() and + * blk_mq_unfreeze_queue(). */ struct request_queue { struct request *last_merge; struct elevator_queue *elevator; - struct blk_queue_stats *stats; struct rq_qos *rq_qos; - make_request_fn *make_request_fn; - const struct blk_mq_ops *mq_ops; - - /* sw queues */ struct blk_mq_ctx __percpu *queue_ctx; - unsigned int queue_depth; - - /* hw dispatch queues */ struct blk_mq_hw_ctx **queue_hw_ctx; unsigned int nr_hw_queues; - struct backing_dev_info *backing_dev_info; - - /* - * The queue owner gets to use this for whatever they like. - * ll_rw_blk doesn't touch it. - */ void *queuedata; - - /* - * various queue flags, see QUEUE_* below - */ unsigned long queue_flags; - /* - * Number of contexts that have called blk_set_pm_only(). If this - * counter is above zero then only RQF_PM and RQF_PREEMPT requests are - * processed. - */ atomic_t pm_only; - - /* - * ida allocated id for this queue. Used to index queues from - * ioctx. - */ int id; - - /* - * queue needs bounce pages for pages above this limit - */ gfp_t bounce_gfp; - spinlock_t queue_lock; - - /* - * queue kobject - */ struct kobject kobj; - - /* - * mq queue kobject - */ struct kobject *mq_kobj; #ifdef CONFIG_BLK_DEV_INTEGRITY @@ -485,66 +483,32 @@ struct request_queue { int rpm_status; unsigned int nr_pending; #endif - - /* - * queue settings - */ - unsigned long nr_requests; /* Max # of requests */ - + unsigned long nr_requests; unsigned int dma_pad_mask; unsigned int dma_alignment; - #ifdef CONFIG_BLK_INLINE_ENCRYPTION - /* Inline crypto capabilities */ struct blk_keyslot_manager *ksm; #endif - unsigned int rq_timeout; int poll_nsec; - struct blk_stat_callback *poll_cb; struct blk_rq_stat poll_stat[BLK_MQ_POLL_STATS_BKTS]; - struct timer_list timeout; struct work_struct timeout_work; - struct list_head icq_list; #ifdef CONFIG_BLK_CGROUP DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); struct blkcg_gq *root_blkg; struct list_head blkg_list; #endif - struct queue_limits limits; - unsigned int required_elevator_features; - #ifdef CONFIG_BLK_DEV_ZONED - /* - * Zoned block device information for request dispatch control. - * nr_zones is the total number of zones of the device. This is always - * 0 for regular block devices. conv_zones_bitmap is a bitmap of nr_zones - * bits which indicates if a zone is conventional (bit set) or - * sequential (bit clear). seq_zones_wlock is a bitmap of nr_zones - * bits which indicates if a zone is write locked, that is, if a write - * request targeting the zone was dispatched. All three fields are - * initialized by the low level device driver (e.g. scsi/sd.c). - * Stacking drivers (device mappers) may or may not initialize - * these fields. - * - * Reads of this information must be protected with blk_queue_enter() / - * blk_queue_exit(). Modifying this information is only allowed while - * no requests are being processed. See also blk_mq_freeze_queue() and - * blk_mq_unfreeze_queue(). - */ unsigned int nr_zones; unsigned long *conv_zones_bitmap; unsigned long *seq_zones_wlock; #endif /* CONFIG_BLK_DEV_ZONED */ - /* - * sg stuff - */ unsigned int sg_timeout; unsigned int sg_reserved_size; int node; @@ -552,59 +516,36 @@ struct request_queue { #ifdef CONFIG_BLK_DEV_IO_TRACE struct blk_trace __rcu *blk_trace; #endif - /* - * for flush operations - */ struct blk_flush_queue *fq; - struct list_head requeue_list; spinlock_t requeue_lock; struct delayed_work requeue_work; - struct mutex sysfs_lock; struct mutex sysfs_dir_lock; - - /* - * for reusing dead hctx instance in case of updating - * nr_hw_queues - */ struct list_head unused_hctx_list; spinlock_t unused_hctx_lock; - int mq_freeze_depth; - #if defined(CONFIG_BLK_DEV_BSG) struct bsg_class_device bsg_dev; #endif #ifdef CONFIG_BLK_DEV_THROTTLING - /* Throttle data */ struct throtl_data *td; #endif struct rcu_head rcu_head; wait_queue_head_t mq_freeze_wq; - /* - * Protect concurrent access to q_usage_counter by - * percpu_ref_kill() and percpu_ref_reinit(). - */ struct mutex mq_freeze_lock; struct percpu_ref q_usage_counter; - struct blk_mq_tag_set *tag_set; struct list_head tag_set_list; struct bio_set bio_split; - struct dentry *debugfs_dir; - #ifdef CONFIG_BLK_DEBUG_FS struct dentry *sched_debugfs_dir; struct dentry *rqos_debugfs_dir; #endif - bool mq_sysfs_init_done; - size_t cmd_size; - #define BLK_MAX_WRITE_HINTS 5 u64 write_hints[BLK_MAX_WRITE_HINTS]; }; -- 2.26.2
