1 files changed, 441 insertions, 0 deletions
diff --git a/block/blk.h b/block/blk.h
new file mode 100644
index 000000000..ae87e2a5f
--- /dev/null
+++ b/block/blk.h
@@ -0,0 +1,441 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef BLK_INTERNAL_H
+#define BLK_INTERNAL_H
+
+#include <linux/idr.h>
+#include <linux/blk-mq.h>
+#include "blk-mq.h"
+
+/* Amount of time in which a process may batch requests */
+#define BLK_BATCH_TIME	(HZ/50UL)
+
+/* Number of requests a "batching" process may submit */
+#define BLK_BATCH_REQ	32
+
+/* Max future timer expiry for timeouts */
+#define BLK_MAX_TIMEOUT		(5 * HZ)
+
+#ifdef CONFIG_DEBUG_FS
+extern struct dentry *blk_debugfs_root;
+#endif
+
+struct blk_flush_queue {
+	unsigned int		flush_queue_delayed:1;
+	unsigned int		flush_pending_idx:1;
+	unsigned int		flush_running_idx:1;
+	blk_status_t 		rq_status;
+	unsigned long		flush_pending_since;
+	struct list_head	flush_queue[2];
+	struct list_head	flush_data_in_flight;
+	struct request		*flush_rq;
+
+	/*
+	 * flush_rq shares tag with this rq, both can't be active
+	 * at the same time
+	 */
+	struct request		*orig_rq;
+	spinlock_t		mq_flush_lock;
+};
+
+extern struct kmem_cache *blk_requestq_cachep;
+extern struct kmem_cache *request_cachep;
+extern struct kobj_type blk_queue_ktype;
+extern struct ida blk_queue_ida;
+
+/*
+ * @q->queue_lock is set while a queue is being initialized. Since we know
+ * that no other threads access the queue object before @q->queue_lock has
+ * been set, it is safe to manipulate queue flags without holding the
+ * queue_lock if @q->queue_lock == NULL. See also blk_alloc_queue_node() and
+ * blk_init_allocated_queue().
+ */
+static inline void queue_lockdep_assert_held(struct request_queue *q)
+{
+	if (q->queue_lock)
+		lockdep_assert_held(q->queue_lock);
+}
+
+static inline void queue_flag_set_unlocked(unsigned int flag,
+					   struct request_queue *q)
+{
+	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&
+	    kref_read(&q->kobj.kref))
+		lockdep_assert_held(q->queue_lock);
+	__set_bit(flag, &q->queue_flags);
+}
+
+static inline void queue_flag_clear_unlocked(unsigned int flag,
+					     struct request_queue *q)
+{
+	if (test_bit(QUEUE_FLAG_INIT_DONE, &q->queue_flags) &&
+	    kref_read(&q->kobj.kref))
+		lockdep_assert_held(q->queue_lock);
+	__clear_bit(flag, &q->queue_flags);
+}
+
+static inline int queue_flag_test_and_clear(unsigned int flag,
+					    struct request_queue *q)
+{
+	queue_lockdep_assert_held(q);
+
+	if (test_bit(flag, &q->queue_flags)) {
+		__clear_bit(flag, &q->queue_flags);
+		return 1;
+	}
+
+	return 0;
+}
+
+static inline int queue_flag_test_and_set(unsigned int flag,
+					  struct request_queue *q)
+{
+	queue_lockdep_assert_held(q);
+
+	if (!test_bit(flag, &q->queue_flags)) {
+		__set_bit(flag, &q->queue_flags);
+		return 0;
+	}
+
+	return 1;
+}
+
+static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
+{
+	queue_lockdep_assert_held(q);
+	__set_bit(flag, &q->queue_flags);
+}
+
+static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
+{
+	queue_lockdep_assert_held(q);
+	__clear_bit(flag, &q->queue_flags);
+}
+
+static inline struct blk_flush_queue *blk_get_flush_queue(
+		struct request_queue *q, struct blk_mq_ctx *ctx)
+{
+	if (q->mq_ops)
+		return blk_mq_map_queue(q, ctx->cpu)->fq;
+	return q->fq;
+}
+
+static inline void __blk_get_queue(struct request_queue *q)
+{
+	kobject_get(&q->kobj);
+}
+
+static inline bool
+is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
+{
+	return hctx->fq->flush_rq == req;
+}
+
+struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
+		int node, int cmd_size, gfp_t flags);
+void blk_free_flush_queue(struct blk_flush_queue *q);
+
+int blk_init_rl(struct request_list *rl, struct request_queue *q,
+		gfp_t gfp_mask);
+void blk_exit_rl(struct request_queue *q, struct request_list *rl);
+void blk_exit_queue(struct request_queue *q);
+void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
+			struct bio *bio);
+void blk_queue_bypass_start(struct request_queue *q);
+void blk_queue_bypass_end(struct request_queue *q);
+void __blk_queue_free_tags(struct request_queue *q);
+void blk_freeze_queue(struct request_queue *q);
+
+static inline void blk_queue_enter_live(struct request_queue *q)
+{
+	/*
+	 * Given that running in generic_make_request() context
+	 * guarantees that a live reference against q_usage_counter has
+	 * been established, further references under that same context
+	 * need not check that the queue has been frozen (marked dead).
+	 */
+	percpu_ref_get(&q->q_usage_counter);
+}
+
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+void blk_flush_integrity(void);
+bool __bio_integrity_endio(struct bio *);
+static inline bool bio_integrity_endio(struct bio *bio)
+{
+	if (bio_integrity(bio))
+		return __bio_integrity_endio(bio);
+	return true;
+}
+#else
+static inline void blk_flush_integrity(void)
+{
+}
+static inline bool bio_integrity_endio(struct bio *bio)
+{
+	return true;
+}
+#endif
+
+void blk_timeout_work(struct work_struct *work);
+unsigned long blk_rq_timeout(unsigned long timeout);
+void blk_add_timer(struct request *req);
+void blk_delete_timer(struct request *);
+
+
+bool bio_attempt_front_merge(struct request_queue *q, struct request *req,
+			     struct bio *bio);
+bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
+			    struct bio *bio);
+bool bio_attempt_discard_merge(struct request_queue *q, struct request *req,
+		struct bio *bio);
+bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
+			    unsigned int *request_count,
+			    struct request **same_queue_rq);
+unsigned int blk_plug_queued_count(struct request_queue *q);
+
+void blk_account_io_start(struct request *req, bool new_io);
+void blk_account_io_completion(struct request *req, unsigned int bytes);
+void blk_account_io_done(struct request *req, u64 now);
+
+/*
+ * EH timer and IO completion will both attempt to 'grab' the request, make
+ * sure that only one of them succeeds. Steal the bottom bit of the
+ * __deadline field for this.
+ */
+static inline int blk_mark_rq_complete(struct request *rq)
+{
+	return test_and_set_bit(0, &rq->__deadline);
+}
+
+static inline void blk_clear_rq_complete(struct request *rq)
+{
+	clear_bit(0, &rq->__deadline);
+}
+
+static inline bool blk_rq_is_complete(struct request *rq)
+{
+	return test_bit(0, &rq->__deadline);
+}
+
+/*
+ * Internal elevator interface
+ */
+#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
+
+void blk_insert_flush(struct request *rq);
+
+static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
+{
+	struct elevator_queue *e = q->elevator;
+
+	if (e->type->ops.sq.elevator_activate_req_fn)
+		e->type->ops.sq.elevator_activate_req_fn(q, rq);
+}
+
+static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq)
+{
+	struct elevator_queue *e = q->elevator;
+
+	if (e->type->ops.sq.elevator_deactivate_req_fn)
+		e->type->ops.sq.elevator_deactivate_req_fn(q, rq);
+}
+
+int elevator_init(struct request_queue *);
+int elevator_init_mq(struct request_queue *q);
+int elevator_switch_mq(struct request_queue *q,
+			      struct elevator_type *new_e);
+void elevator_exit(struct request_queue *, struct elevator_queue *);
+int elv_register_queue(struct request_queue *q, bool uevent);
+void elv_unregister_queue(struct request_queue *q);
+
+struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
+
+#ifdef CONFIG_FAIL_IO_TIMEOUT
+int blk_should_fake_timeout(struct request_queue *);
+ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
+ssize_t part_timeout_store(struct device *, struct device_attribute *,
+				const char *, size_t);
+#else
+static inline int blk_should_fake_timeout(struct request_queue *q)
+{
+	return 0;
+}
+#endif
+
+int ll_back_merge_fn(struct request_queue *q, struct request *req,
+		     struct bio *bio);
+int ll_front_merge_fn(struct request_queue *q, struct request *req, 
+		      struct bio *bio);
+struct request *attempt_back_merge(struct request_queue *q, struct request *rq);
+struct request *attempt_front_merge(struct request_queue *q, struct request *rq);
+int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
+				struct request *next);
+void blk_recalc_rq_segments(struct request *rq);
+void blk_rq_set_mixed_merge(struct request *rq);
+bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
+enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
+
+void blk_queue_congestion_threshold(struct request_queue *q);
+
+int blk_dev_init(void);
+
+
+/*
+ * Return the threshold (number of used requests) at which the queue is
+ * considered to be congested.  It include a little hysteresis to keep the
+ * context switch rate down.
+ */
+static inline int queue_congestion_on_threshold(struct request_queue *q)
+{
+	return q->nr_congestion_on;
+}
+
+/*
+ * The threshold at which a queue is considered to be uncongested
+ */
+static inline int queue_congestion_off_threshold(struct request_queue *q)
+{
+	return q->nr_congestion_off;
+}
+
+extern int blk_update_nr_requests(struct request_queue *, unsigned int);
+
+/*
+ * Contribute to IO statistics IFF:
+ *
+ *	a) it's attached to a gendisk, and
+ *	b) the queue had IO stats enabled when this request was started, and
+ *	c) it's a file system request
+ */
+static inline bool blk_do_io_stat(struct request *rq)
+{
+	return rq->rq_disk &&
+	       (rq->rq_flags & RQF_IO_STAT) &&
+		!blk_rq_is_passthrough(rq);
+}
+
+static inline void req_set_nomerge(struct request_queue *q, struct request *req)
+{
+	req->cmd_flags |= REQ_NOMERGE;
+	if (req == q->last_merge)
+		q->last_merge = NULL;
+}
+
+/*
+ * Steal a bit from this field for legacy IO path atomic IO marking. Note that
+ * setting the deadline clears the bottom bit, potentially clearing the
+ * completed bit. The user has to be OK with this (current ones are fine).
+ */
+static inline void blk_rq_set_deadline(struct request *rq, unsigned long time)
+{
+	rq->__deadline = time & ~0x1UL;
+}
+
+static inline unsigned long blk_rq_deadline(struct request *rq)
+{
+	return rq->__deadline & ~0x1UL;
+}
+
+/*
+ * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
+ * is defined as 'unsigned int', meantime it has to aligned to with logical
+ * block size which is the minimum accepted unit by hardware.
+ */
+static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
+{
+	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
+}
+
+/*
+ * Internal io_context interface
+ */
+void get_io_context(struct io_context *ioc);
+struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
+struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
+			     gfp_t gfp_mask);
+void ioc_clear_queue(struct request_queue *q);
+
+int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
+
+/**
+ * rq_ioc - determine io_context for request allocation
+ * @bio: request being allocated is for this bio (can be %NULL)
+ *
+ * Determine io_context to use for request allocation for @bio.  May return
+ * %NULL if %current->io_context doesn't exist.
+ */
+static inline struct io_context *rq_ioc(struct bio *bio)
+{
+#ifdef CONFIG_BLK_CGROUP
+	if (bio && bio->bi_ioc)
+		return bio->bi_ioc;
+#endif
+	return current->io_context;
+}
+
+/**
+ * create_io_context - try to create task->io_context
+ * @gfp_mask: allocation mask
+ * @node: allocation node
+ *
+ * If %current->io_context is %NULL, allocate a new io_context and install
+ * it.  Returns the current %current->io_context which may be %NULL if
+ * allocation failed.
+ *
+ * Note that this function can't be called with IRQ disabled because
+ * task_lock which protects %current->io_context is IRQ-unsafe.
+ */
+static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
+{
+	WARN_ON_ONCE(irqs_disabled());
+	if (unlikely(!current->io_context))
+		create_task_io_context(current, gfp_mask, node);
+	return current->io_context;
+}
+
+/*
+ * Internal throttling interface
+ */
+#ifdef CONFIG_BLK_DEV_THROTTLING
+extern void blk_throtl_drain(struct request_queue *q);
+extern int blk_throtl_init(struct request_queue *q);
+extern void blk_throtl_exit(struct request_queue *q);
+extern void blk_throtl_register_queue(struct request_queue *q);
+#else /* CONFIG_BLK_DEV_THROTTLING */
+static inline void blk_throtl_drain(struct request_queue *q) { }
+static inline int blk_throtl_init(struct request_queue *q) { return 0; }
+static inline void blk_throtl_exit(struct request_queue *q) { }
+static inline void blk_throtl_register_queue(struct request_queue *q) { }
+#endif /* CONFIG_BLK_DEV_THROTTLING */
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
+extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
+extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
+	const char *page, size_t count);
+extern void blk_throtl_bio_endio(struct bio *bio);
+extern void blk_throtl_stat_add(struct request *rq, u64 time);
+#else
+static inline void blk_throtl_bio_endio(struct bio *bio) { }
+static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
+#endif
+
+#ifdef CONFIG_BOUNCE
+extern int init_emergency_isa_pool(void);
+extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
+#else
+static inline int init_emergency_isa_pool(void)
+{
+	return 0;
+}
+static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
+{
+}
+#endif /* CONFIG_BOUNCE */
+
+extern void blk_drain_queue(struct request_queue *q);
+
+#ifdef CONFIG_BLK_CGROUP_IOLATENCY
+extern int blk_iolatency_init(struct request_queue *q);
+#else
+static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
+#endif
+
+#endif /* BLK_INTERNAL_H */