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 <snitzer@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
new file mode 100644
index 0000000..40ceba1
--- /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 <linux/kthread.h>
+#include <linux/ktime.h>
+#include <linux/blk-mq.h>
+
+#include <trace/events/block.h>
+
+#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