swh:1:snp:13806c77fd4b7f42b1e985e730bd615fd52cfac1
Tip revision: 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 authored by Linus Torvalds on 31 May 2020, 23:49:15 UTC
Linux 5.7
Linux 5.7
Tip revision: 3d77e6a
blk.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BLK_INTERNAL_H
#define BLK_INTERNAL_H
#include <linux/idr.h>
#include <linux/blk-mq.h>
#include <linux/part_stat.h>
#include <xen/xen.h>
#include "blk-mq.h"
#include "blk-mq-sched.h"
/* 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;
struct lock_class_key key;
spinlock_t mq_flush_lock;
};
extern struct kmem_cache *blk_requestq_cachep;
extern struct kobj_type blk_queue_ktype;
extern struct ida blk_queue_ida;
static inline struct blk_flush_queue *
blk_get_flush_queue(struct request_queue *q, struct blk_mq_ctx *ctx)
{
return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->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(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);
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);
}
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;
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 request_queue *q,
struct bio_vec *bprv, unsigned int offset)
{
return (offset & queue_virt_boundary(q)) ||
((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
}
/*
* 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 request_queue *q,
struct bio_vec *bprv, unsigned int offset)
{
if (!queue_virt_boundary(q))
return false;
return __bvec_gap_to_prev(q, bprv, offset);
}
static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
unsigned int nr_segs)
{
rq->nr_phys_segments = nr_segs;
rq->__data_len = bio->bi_iter.bi_size;
rq->bio = rq->biotail = bio;
rq->ioprio = bio_prio(bio);
if (bio->bi_disk)
rq->rq_disk = bio->bi_disk;
}
#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;
}
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, &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, &bip->bip_vec[bip->bip_vcnt - 1],
bip_next->bip_vec[0].bv_offset);
}
void blk_integrity_add(struct gendisk *);
void blk_integrity_del(struct gendisk *);
#else /* CONFIG_BLK_DEV_INTEGRITY */
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 void blk_integrity_add(struct gendisk *disk)
{
}
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);
bool bio_attempt_front_merge(struct request *req, struct bio *bio,
unsigned int nr_segs);
bool bio_attempt_back_merge(struct request *req, struct bio *bio,
unsigned int nr_segs);
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 nr_segs, struct request **same_queue_rq);
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);
/*
* Internal elevator interface
*/
#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
void blk_insert_flush(struct request *rq);
void 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);
static inline void elevator_exit(struct request_queue *q,
struct elevator_queue *e)
{
lockdep_assert_held(&q->sysfs_lock);
blk_mq_sched_free_requests(q);
__elevator_exit(q, e);
}
struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
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);
#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
void __blk_queue_split(struct request_queue *q, struct bio **bio,
unsigned int *nr_segs);
int ll_back_merge_fn(struct request *req, struct bio *bio,
unsigned int nr_segs);
int ll_front_merge_fn(struct request *req, struct bio *bio,
unsigned int nr_segs);
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);
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);
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_disk && (rq->rq_flags & RQF_IO_STAT);
}
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;
}
/*
* 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);
/**
* 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 */
#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
struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
#ifdef CONFIG_BLK_DEV_ZONED
void blk_queue_free_zone_bitmaps(struct request_queue *q);
#else
static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
#endif
void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
int rw);
void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
int rw);
void update_io_ticks(struct hd_struct *part, unsigned long now, bool end);
struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
void blk_free_devt(dev_t devt);
void blk_invalidate_devt(dev_t devt);
char *disk_name(struct gendisk *hd, int partno, char *buf);
#define ADDPART_FLAG_NONE 0
#define ADDPART_FLAG_RAID 1
#define ADDPART_FLAG_WHOLEDISK 2
struct hd_struct *__must_check add_partition(struct gendisk *disk, int partno,
sector_t start, sector_t len, int flags,
struct partition_meta_info *info);
void __delete_partition(struct percpu_ref *ref);
void delete_partition(struct gendisk *disk, int partno);
int disk_expand_part_tbl(struct gendisk *disk, int target);
static inline int hd_ref_init(struct hd_struct *part)
{
if (percpu_ref_init(&part->ref, __delete_partition, 0,
GFP_KERNEL))
return -ENOMEM;
return 0;
}
static inline void hd_struct_get(struct hd_struct *part)
{
percpu_ref_get(&part->ref);
}
static inline int hd_struct_try_get(struct hd_struct *part)
{
return percpu_ref_tryget_live(&part->ref);
}
static inline void hd_struct_put(struct hd_struct *part)
{
percpu_ref_put(&part->ref);
}
static inline void hd_struct_kill(struct hd_struct *part)
{
percpu_ref_kill(&part->ref);
}
static inline void hd_free_part(struct hd_struct *part)
{
free_part_stats(part);
kfree(part->info);
percpu_ref_exit(&part->ref);
}
/*
* Any access of part->nr_sects which is not protected by partition
* bd_mutex or gendisk bdev bd_mutex, should be done using this
* accessor function.
*
* Code written along the lines of i_size_read() and i_size_write().
* CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
* on.
*/
static inline sector_t part_nr_sects_read(struct hd_struct *part)
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
sector_t nr_sects;
unsigned seq;
do {
seq = read_seqcount_begin(&part->nr_sects_seq);
nr_sects = part->nr_sects;
} while (read_seqcount_retry(&part->nr_sects_seq, seq));
return nr_sects;
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
sector_t nr_sects;
preempt_disable();
nr_sects = part->nr_sects;
preempt_enable();
return nr_sects;
#else
return part->nr_sects;
#endif
}
/*
* Should be called with mutex lock held (typically bd_mutex) of partition
* to provide mutual exlusion among writers otherwise seqcount might be
* left in wrong state leaving the readers spinning infinitely.
*/
static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
write_seqcount_begin(&part->nr_sects_seq);
part->nr_sects = size;
write_seqcount_end(&part->nr_sects_seq);
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
preempt_disable();
part->nr_sects = size;
preempt_enable();
#else
part->nr_sects = size;
#endif
}
struct request_queue *__blk_alloc_queue(int node_id);
int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
struct page *page, unsigned int len, unsigned int offset,
bool *same_page);
#endif /* BLK_INTERNAL_H */