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-rw-r--r--block/blk.h521
1 files changed, 521 insertions, 0 deletions
diff --git a/block/blk.h b/block/blk.h
new file mode 100644
index 0000000000..08a358bc09
--- /dev/null
+++ b/block/blk.h
@@ -0,0 +1,521 @@
+/* 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 {
+ spinlock_t mq_flush_lock;
+ 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];
+ unsigned long flush_data_in_flight;
+ struct request *flush_rq;
+};
+
+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);
+
+bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv,
+ struct page *page, unsigned len, unsigned offset,
+ bool *same_page);
+
+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(const 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(const 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_rq_get_max_segments(struct request *rq)
+{
+ if (req_op(rq) == REQ_OP_DISCARD)
+ return queue_max_discard_segments(rq->q);
+ return queue_max_segments(rq->q);
+}
+
+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);
+}
+
+extern const struct attribute_group blk_integrity_attr_group;
+#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)
+{
+}
+#endif /* CONFIG_BLK_DEV_INTEGRITY */
+
+unsigned long blk_rq_timeout(unsigned long timeout);
+void blk_add_timer(struct request *req);
+
+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)
+
+bool blk_insert_flush(struct request *rq);
+
+int elevator_switch(struct request_queue *q, struct elevator_type *new_e);
+void elevator_disable(struct request_queue *q);
+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,
+ const 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,
+ const 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_DEV_ZONED
+void disk_free_zone_bitmaps(struct gendisk *disk);
+void disk_clear_zone_settings(struct gendisk *disk);
+int blkdev_report_zones_ioctl(struct block_device *bdev, unsigned int cmd,
+ unsigned long arg);
+int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode,
+ unsigned int cmd, unsigned long arg);
+#else /* CONFIG_BLK_DEV_ZONED */
+static inline void disk_free_zone_bitmaps(struct gendisk *disk) {}
+static inline void disk_clear_zone_settings(struct gendisk *disk) {}
+static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
+ unsigned int cmd, unsigned long arg)
+{
+ return -ENOTTY;
+}
+static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
+ blk_mode_t mode, unsigned int cmd, unsigned long arg)
+{
+ return -ENOTTY;
+}
+#endif /* CONFIG_BLK_DEV_ZONED */
+
+struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
+void bdev_add(struct block_device *bdev, dev_t dev);
+
+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 drop_partition(struct block_device *part);
+
+void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors);
+
+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);
+
+/*
+ * Clean up a page appropriately, where the page may be pinned, may have a
+ * ref taken on it or neither.
+ */
+static inline void bio_release_page(struct bio *bio, struct page *page)
+{
+ if (bio_flagged(bio, BIO_PAGE_PINNED))
+ unpin_user_page(page);
+}
+
+struct request_queue *blk_alloc_queue(int node_id);
+
+int disk_scan_partitions(struct gendisk *disk, blk_mode_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;
+
+blk_mode_t file_to_blk_mode(struct file *file);
+int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
+ loff_t lstart, loff_t lend);
+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 */