diff options
Diffstat (limited to 'block/blk.h')
-rw-r--r-- | block/blk.h | 503 |
1 files changed, 503 insertions, 0 deletions
diff --git a/block/blk.h b/block/blk.h new file mode 100644 index 000000000..a186ea20f --- /dev/null +++ b/block/blk.h @@ -0,0 +1,503 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef BLK_INTERNAL_H +#define BLK_INTERNAL_H + +#include <linux/blk-crypto.h> +#include <linux/memblock.h> /* for max_pfn/max_low_pfn */ +#include <xen/xen.h> +#include "blk-crypto-internal.h" + +struct elevator_type; + +/* Max future timer expiry for timeouts */ +#define BLK_MAX_TIMEOUT (5 * HZ) + +extern struct dentry *blk_debugfs_root; + +struct blk_flush_queue { + 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; + + spinlock_t mq_flush_lock; +}; + +extern struct kmem_cache *blk_requestq_cachep; +extern struct kmem_cache *blk_requestq_srcu_cachep; +extern struct kobj_type blk_queue_ktype; +extern struct ida blk_queue_ida; + +bool is_flush_rq(struct request *req); + +struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size, + gfp_t flags); +void blk_free_flush_queue(struct blk_flush_queue *q); + +void blk_freeze_queue(struct request_queue *q); +void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic); +void blk_queue_start_drain(struct request_queue *q); +int __bio_queue_enter(struct request_queue *q, struct bio *bio); +void submit_bio_noacct_nocheck(struct bio *bio); + +static inline bool blk_try_enter_queue(struct request_queue *q, bool pm) +{ + rcu_read_lock(); + if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter)) + goto fail; + + /* + * The code that increments the pm_only counter must ensure that the + * counter is globally visible before the queue is unfrozen. + */ + if (blk_queue_pm_only(q) && + (!pm || queue_rpm_status(q) == RPM_SUSPENDED)) + goto fail_put; + + rcu_read_unlock(); + return true; + +fail_put: + blk_queue_exit(q); +fail: + rcu_read_unlock(); + return false; +} + +static inline int bio_queue_enter(struct bio *bio) +{ + struct request_queue *q = bdev_get_queue(bio->bi_bdev); + + if (blk_try_enter_queue(q, false)) + return 0; + return __bio_queue_enter(q, bio); +} + +#define BIO_INLINE_VECS 4 +struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs, + gfp_t gfp_mask); +void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs); + +static inline bool biovec_phys_mergeable(struct request_queue *q, + struct bio_vec *vec1, struct bio_vec *vec2) +{ + unsigned long mask = queue_segment_boundary(q); + phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset; + phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset; + + /* + * Merging adjacent physical pages may not work correctly under KMSAN + * if their metadata pages aren't adjacent. Just disable merging. + */ + if (IS_ENABLED(CONFIG_KMSAN)) + return false; + + if (addr1 + vec1->bv_len != addr2) + return false; + if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page)) + return false; + if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask)) + return false; + return true; +} + +static inline bool __bvec_gap_to_prev(struct queue_limits *lim, + struct bio_vec *bprv, unsigned int offset) +{ + return (offset & lim->virt_boundary_mask) || + ((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask); +} + +/* + * Check if adding a bio_vec after bprv with offset would create a gap in + * the SG list. Most drivers don't care about this, but some do. + */ +static inline bool bvec_gap_to_prev(struct queue_limits *lim, + struct bio_vec *bprv, unsigned int offset) +{ + if (!lim->virt_boundary_mask) + return false; + return __bvec_gap_to_prev(lim, bprv, offset); +} + +static inline bool rq_mergeable(struct request *rq) +{ + if (blk_rq_is_passthrough(rq)) + return false; + + if (req_op(rq) == REQ_OP_FLUSH) + return false; + + if (req_op(rq) == REQ_OP_WRITE_ZEROES) + return false; + + if (req_op(rq) == REQ_OP_ZONE_APPEND) + return false; + + if (rq->cmd_flags & REQ_NOMERGE_FLAGS) + return false; + if (rq->rq_flags & RQF_NOMERGE_FLAGS) + return false; + + return true; +} + +/* + * There are two different ways to handle DISCARD merges: + * 1) If max_discard_segments > 1, the driver treats every bio as a range and + * send the bios to controller together. The ranges don't need to be + * contiguous. + * 2) Otherwise, the request will be normal read/write requests. The ranges + * need to be contiguous. + */ +static inline bool blk_discard_mergable(struct request *req) +{ + if (req_op(req) == REQ_OP_DISCARD && + queue_max_discard_segments(req->q) > 1) + return true; + return false; +} + +static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, + enum req_op op) +{ + if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE)) + return min(q->limits.max_discard_sectors, + UINT_MAX >> SECTOR_SHIFT); + + if (unlikely(op == REQ_OP_WRITE_ZEROES)) + return q->limits.max_write_zeroes_sectors; + + return q->limits.max_sectors; +} + +#ifdef CONFIG_BLK_DEV_INTEGRITY +void blk_flush_integrity(void); +bool __bio_integrity_endio(struct bio *); +void bio_integrity_free(struct bio *bio); +static inline bool bio_integrity_endio(struct bio *bio) +{ + if (bio_integrity(bio)) + return __bio_integrity_endio(bio); + return true; +} + +bool blk_integrity_merge_rq(struct request_queue *, struct request *, + struct request *); +bool blk_integrity_merge_bio(struct request_queue *, struct request *, + struct bio *); + +static inline bool integrity_req_gap_back_merge(struct request *req, + struct bio *next) +{ + struct bio_integrity_payload *bip = bio_integrity(req->bio); + struct bio_integrity_payload *bip_next = bio_integrity(next); + + return bvec_gap_to_prev(&req->q->limits, + &bip->bip_vec[bip->bip_vcnt - 1], + bip_next->bip_vec[0].bv_offset); +} + +static inline bool integrity_req_gap_front_merge(struct request *req, + struct bio *bio) +{ + struct bio_integrity_payload *bip = bio_integrity(bio); + struct bio_integrity_payload *bip_next = bio_integrity(req->bio); + + return bvec_gap_to_prev(&req->q->limits, + &bip->bip_vec[bip->bip_vcnt - 1], + bip_next->bip_vec[0].bv_offset); +} + +int blk_integrity_add(struct gendisk *disk); +void blk_integrity_del(struct gendisk *); +#else /* CONFIG_BLK_DEV_INTEGRITY */ +static inline bool blk_integrity_merge_rq(struct request_queue *rq, + struct request *r1, struct request *r2) +{ + return true; +} +static inline bool blk_integrity_merge_bio(struct request_queue *rq, + struct request *r, struct bio *b) +{ + return true; +} +static inline bool integrity_req_gap_back_merge(struct request *req, + struct bio *next) +{ + return false; +} +static inline bool integrity_req_gap_front_merge(struct request *req, + struct bio *bio) +{ + return false; +} + +static inline void blk_flush_integrity(void) +{ +} +static inline bool bio_integrity_endio(struct bio *bio) +{ + return true; +} +static inline void bio_integrity_free(struct bio *bio) +{ +} +static inline int blk_integrity_add(struct gendisk *disk) +{ + return 0; +} +static inline void blk_integrity_del(struct gendisk *disk) +{ +} +#endif /* CONFIG_BLK_DEV_INTEGRITY */ + +unsigned long blk_rq_timeout(unsigned long timeout); +void blk_add_timer(struct request *req); +const char *blk_status_to_str(blk_status_t status); + +bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, + unsigned int nr_segs); +bool blk_bio_list_merge(struct request_queue *q, struct list_head *list, + struct bio *bio, unsigned int nr_segs); + +/* + * Plug flush limits + */ +#define BLK_MAX_REQUEST_COUNT 32 +#define BLK_PLUG_FLUSH_SIZE (128 * 1024) + +/* + * Internal elevator interface + */ +#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED) + +void blk_insert_flush(struct request *rq); + +int elevator_switch(struct request_queue *q, struct elevator_type *new_e); +void elevator_exit(struct request_queue *q); +int elv_register_queue(struct request_queue *q, bool uevent); +void elv_unregister_queue(struct request_queue *q); + +ssize_t part_size_show(struct device *dev, struct device_attribute *attr, + char *buf); +ssize_t part_stat_show(struct device *dev, struct device_attribute *attr, + char *buf); +ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr, + char *buf); +ssize_t part_fail_show(struct device *dev, struct device_attribute *attr, + char *buf); +ssize_t part_fail_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count); +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); + +static inline bool bio_may_exceed_limits(struct bio *bio, + struct queue_limits *lim) +{ + switch (bio_op(bio)) { + case REQ_OP_DISCARD: + case REQ_OP_SECURE_ERASE: + case REQ_OP_WRITE_ZEROES: + return true; /* non-trivial splitting decisions */ + default: + break; + } + + /* + * All drivers must accept single-segments bios that are <= PAGE_SIZE. + * This is a quick and dirty check that relies on the fact that + * bi_io_vec[0] is always valid if a bio has data. The check might + * lead to occasional false negatives when bios are cloned, but compared + * to the performance impact of cloned bios themselves the loop below + * doesn't matter anyway. + */ + return lim->chunk_sectors || bio->bi_vcnt != 1 || + bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE; +} + +struct bio *__bio_split_to_limits(struct bio *bio, struct queue_limits *lim, + unsigned int *nr_segs); +int ll_back_merge_fn(struct request *req, struct bio *bio, + unsigned int nr_segs); +bool blk_attempt_req_merge(struct request_queue *q, struct request *rq, + struct request *next); +unsigned int 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_set_default_limits(struct queue_limits *lim); +int blk_dev_init(void); + +/* + * 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 + */ +static inline bool blk_do_io_stat(struct request *rq) +{ + return (rq->rq_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq); +} + +void update_io_ticks(struct block_device *part, unsigned long now, bool end); + +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; +} + +/* + * Internal io_context interface + */ +struct io_cq *ioc_find_get_icq(struct request_queue *q); +struct io_cq *ioc_lookup_icq(struct request_queue *q); +#ifdef CONFIG_BLK_ICQ +void ioc_clear_queue(struct request_queue *q); +#else +static inline void ioc_clear_queue(struct request_queue *q) +{ +} +#endif /* CONFIG_BLK_ICQ */ + +#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 + +struct bio *__blk_queue_bounce(struct bio *bio, struct request_queue *q); + +static inline bool blk_queue_may_bounce(struct request_queue *q) +{ + return IS_ENABLED(CONFIG_BOUNCE) && + q->limits.bounce == BLK_BOUNCE_HIGH && + max_low_pfn >= max_pfn; +} + +static inline struct bio *blk_queue_bounce(struct bio *bio, + struct request_queue *q) +{ + if (unlikely(blk_queue_may_bounce(q) && bio_has_data(bio))) + return __blk_queue_bounce(bio, q); + return bio; +} + +#ifdef CONFIG_BLK_CGROUP_IOLATENCY +int blk_iolatency_init(struct gendisk *disk); +#else +static inline int blk_iolatency_init(struct gendisk *disk) { return 0; }; +#endif + +#ifdef CONFIG_BLK_DEV_ZONED +void disk_free_zone_bitmaps(struct gendisk *disk); +void disk_clear_zone_settings(struct gendisk *disk); +#else +static inline void disk_free_zone_bitmaps(struct gendisk *disk) {} +static inline void disk_clear_zone_settings(struct gendisk *disk) {} +#endif + +int blk_alloc_ext_minor(void); +void blk_free_ext_minor(unsigned int minor); +#define ADDPART_FLAG_NONE 0 +#define ADDPART_FLAG_RAID 1 +#define ADDPART_FLAG_WHOLEDISK 2 +int bdev_add_partition(struct gendisk *disk, int partno, sector_t start, + sector_t length); +int bdev_del_partition(struct gendisk *disk, int partno); +int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start, + sector_t length); +void blk_drop_partitions(struct gendisk *disk); + +struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, + struct lock_class_key *lkclass); + +int bio_add_hw_page(struct request_queue *q, struct bio *bio, + struct page *page, unsigned int len, unsigned int offset, + unsigned int max_sectors, bool *same_page); + +static inline struct kmem_cache *blk_get_queue_kmem_cache(bool srcu) +{ + if (srcu) + return blk_requestq_srcu_cachep; + return blk_requestq_cachep; +} +struct request_queue *blk_alloc_queue(int node_id, bool alloc_srcu); + +int disk_scan_partitions(struct gendisk *disk, fmode_t mode); + +int disk_alloc_events(struct gendisk *disk); +void disk_add_events(struct gendisk *disk); +void disk_del_events(struct gendisk *disk); +void disk_release_events(struct gendisk *disk); +void disk_block_events(struct gendisk *disk); +void disk_unblock_events(struct gendisk *disk); +void disk_flush_events(struct gendisk *disk, unsigned int mask); +extern struct device_attribute dev_attr_events; +extern struct device_attribute dev_attr_events_async; +extern struct device_attribute dev_attr_events_poll_msecs; + +extern struct attribute_group blk_trace_attr_group; + +long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg); +long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg); + +extern const struct address_space_operations def_blk_aops; + +int disk_register_independent_access_ranges(struct gendisk *disk); +void disk_unregister_independent_access_ranges(struct gendisk *disk); + +#ifdef CONFIG_FAIL_MAKE_REQUEST +bool should_fail_request(struct block_device *part, unsigned int bytes); +#else /* CONFIG_FAIL_MAKE_REQUEST */ +static inline bool should_fail_request(struct block_device *part, + unsigned int bytes) +{ + return false; +} +#endif /* CONFIG_FAIL_MAKE_REQUEST */ + +/* + * Optimized request reference counting. Ideally we'd make timeouts be more + * clever, as that's the only reason we need references at all... But until + * this happens, this is faster than using refcount_t. Also see: + * + * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count") + */ +#define req_ref_zero_or_close_to_overflow(req) \ + ((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u) + +static inline bool req_ref_inc_not_zero(struct request *req) +{ + return atomic_inc_not_zero(&req->ref); +} + +static inline bool req_ref_put_and_test(struct request *req) +{ + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + return atomic_dec_and_test(&req->ref); +} + +static inline void req_ref_set(struct request *req, int value) +{ + atomic_set(&req->ref, value); +} + +static inline int req_ref_read(struct request *req) +{ + return atomic_read(&req->ref); +} + +#endif /* BLK_INTERNAL_H */ |