From 4cc96131afce3eaae7c13dff41c6ba771cf10e96 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Thu, 12 May 2016 16:28:10 -0400 Subject: dm: move request-based code out to dm-rq.[hc] Add some seperation between bio-based and request-based DM core code. 'struct mapped_device' and other DM core only structures and functions have been moved to dm-core.h and all relevant DM core .c files have been updated to include dm-core.h rather than dm.h DM targets should _never_ include dm-core.h! [block core merge conflict resolution from Stephen Rothwell] Signed-off-by: Mike Snitzer Signed-off-by: Stephen Rothwell --- drivers/md/dm-core.h | 149 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 149 insertions(+) create mode 100644 drivers/md/dm-core.h (limited to 'drivers/md/dm-core.h') diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h new file mode 100644 index 000000000000..40ceba1fe8be --- /dev/null +++ b/drivers/md/dm-core.h @@ -0,0 +1,149 @@ +/* + * Internal header file _only_ for device mapper core + * + * Copyright (C) 2016 Red Hat, Inc. All rights reserved. + * + * This file is released under the LGPL. + */ + +#ifndef DM_CORE_INTERNAL_H +#define DM_CORE_INTERNAL_H + +#include +#include +#include + +#include + +#include "dm.h" + +#define DM_RESERVED_MAX_IOS 1024 + +struct dm_kobject_holder { + struct kobject kobj; + struct completion completion; +}; + +/* + * DM core internal structure that used directly by dm.c and dm-rq.c + * DM targets must _not_ deference a mapped_device to directly access its members! + */ +struct mapped_device { + struct srcu_struct io_barrier; + struct mutex suspend_lock; + + /* + * The current mapping (struct dm_table *). + * Use dm_get_live_table{_fast} or take suspend_lock for + * dereference. + */ + void __rcu *map; + + struct list_head table_devices; + struct mutex table_devices_lock; + + unsigned long flags; + + struct request_queue *queue; + int numa_node_id; + + unsigned type; + /* Protect queue and type against concurrent access. */ + struct mutex type_lock; + + atomic_t holders; + atomic_t open_count; + + struct dm_target *immutable_target; + struct target_type *immutable_target_type; + + struct gendisk *disk; + char name[16]; + + void *interface_ptr; + + /* + * A list of ios that arrived while we were suspended. + */ + atomic_t pending[2]; + wait_queue_head_t wait; + struct work_struct work; + spinlock_t deferred_lock; + struct bio_list deferred; + + /* + * Event handling. + */ + wait_queue_head_t eventq; + atomic_t event_nr; + atomic_t uevent_seq; + struct list_head uevent_list; + spinlock_t uevent_lock; /* Protect access to uevent_list */ + + /* the number of internal suspends */ + unsigned internal_suspend_count; + + /* + * Processing queue (flush) + */ + struct workqueue_struct *wq; + + /* + * io objects are allocated from here. + */ + mempool_t *io_pool; + mempool_t *rq_pool; + + struct bio_set *bs; + + /* + * freeze/thaw support require holding onto a super block + */ + struct super_block *frozen_sb; + + /* forced geometry settings */ + struct hd_geometry geometry; + + struct block_device *bdev; + + /* kobject and completion */ + struct dm_kobject_holder kobj_holder; + + /* zero-length flush that will be cloned and submitted to targets */ + struct bio flush_bio; + + struct dm_stats stats; + + struct kthread_worker kworker; + struct task_struct *kworker_task; + + /* for request-based merge heuristic in dm_request_fn() */ + unsigned seq_rq_merge_deadline_usecs; + int last_rq_rw; + sector_t last_rq_pos; + ktime_t last_rq_start_time; + + /* for blk-mq request-based DM support */ + struct blk_mq_tag_set *tag_set; + bool use_blk_mq:1; + bool init_tio_pdu:1; +}; + +void dm_init_md_queue(struct mapped_device *md); +void dm_init_normal_md_queue(struct mapped_device *md); +int md_in_flight(struct mapped_device *md); +void disable_write_same(struct mapped_device *md); + +static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj) +{ + return &container_of(kobj, struct dm_kobject_holder, kobj)->completion; +} + +unsigned __dm_get_module_param(unsigned *module_param, unsigned def, unsigned max); + +static inline bool dm_message_test_buffer_overflow(char *result, unsigned maxlen) +{ + return !maxlen || strlen(result) + 1 >= maxlen; +} + +#endif -- cgit