1 files changed, 342 insertions, 0 deletions
diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h
new file mode 100644
index 000000000..095b9b49a
--- /dev/null
+++ b/drivers/md/dm-core.h
@@ -0,0 +1,342 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * 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 <linux/blk-crypto-profile.h>
+#include <linux/jump_label.h>
+
+#include <trace/events/block.h>
+
+#include "dm.h"
+#include "dm-ima.h"
+
+#define DM_RESERVED_MAX_IOS		1024
+
+struct dm_io;
+
+struct dm_kobject_holder {
+	struct kobject kobj;
+	struct completion completion;
+};
+
+/*
+ * DM core internal structures used directly by dm.c, dm-rq.c and dm-table.c.
+ * DM targets must _not_ deference a mapped_device or dm_table to directly
+ * access their members!
+ */
+
+/*
+ * For mempools pre-allocation at the table loading time.
+ */
+struct dm_md_mempools {
+	struct bio_set bs;
+	struct bio_set io_bs;
+};
+
+struct mapped_device {
+	struct mutex suspend_lock;
+
+	struct mutex table_devices_lock;
+	struct list_head table_devices;
+
+	/*
+	 * The current mapping (struct dm_table *).
+	 * Use dm_get_live_table{_fast} or take suspend_lock for
+	 * dereference.
+	 */
+	void __rcu *map;
+
+	unsigned long flags;
+
+	/* Protect queue and type against concurrent access. */
+	struct mutex type_lock;
+	enum dm_queue_mode type;
+
+	int numa_node_id;
+	struct request_queue *queue;
+
+	atomic_t holders;
+	atomic_t open_count;
+
+	struct dm_target *immutable_target;
+	struct target_type *immutable_target_type;
+
+	char name[16];
+	struct gendisk *disk;
+	struct dax_device *dax_dev;
+
+	wait_queue_head_t wait;
+	unsigned long __percpu *pending_io;
+
+	/* forced geometry settings */
+	struct hd_geometry geometry;
+
+	/*
+	 * Processing queue (flush)
+	 */
+	struct workqueue_struct *wq;
+
+	/*
+	 * A list of ios that arrived while we were suspended.
+	 */
+	struct work_struct work;
+	spinlock_t deferred_lock;
+	struct bio_list deferred;
+
+	/*
+	 * requeue work context is needed for cloning one new bio
+	 * to represent the dm_io to be requeued, since each
+	 * dm_io may point to the original bio from FS.
+	 */
+	struct work_struct requeue_work;
+	struct dm_io *requeue_list;
+
+	void *interface_ptr;
+
+	/*
+	 * 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 */
+
+	/* for blk-mq request-based DM support */
+	bool init_tio_pdu:1;
+	struct blk_mq_tag_set *tag_set;
+
+	struct dm_stats stats;
+
+	/* the number of internal suspends */
+	unsigned int internal_suspend_count;
+
+	int swap_bios;
+	struct semaphore swap_bios_semaphore;
+	struct mutex swap_bios_lock;
+
+	/*
+	 * io objects are allocated from here.
+	 */
+	struct dm_md_mempools *mempools;
+
+	/* kobject and completion */
+	struct dm_kobject_holder kobj_holder;
+
+	struct srcu_struct io_barrier;
+
+#ifdef CONFIG_BLK_DEV_ZONED
+	unsigned int nr_zones;
+	unsigned int *zwp_offset;
+#endif
+
+#ifdef CONFIG_IMA
+	struct dm_ima_measurements ima;
+#endif
+};
+
+/*
+ * Bits for the flags field of struct mapped_device.
+ */
+#define DMF_BLOCK_IO_FOR_SUSPEND 0
+#define DMF_SUSPENDED 1
+#define DMF_FROZEN 2
+#define DMF_FREEING 3
+#define DMF_DELETING 4
+#define DMF_NOFLUSH_SUSPENDING 5
+#define DMF_DEFERRED_REMOVE 6
+#define DMF_SUSPENDED_INTERNALLY 7
+#define DMF_POST_SUSPENDING 8
+#define DMF_EMULATE_ZONE_APPEND 9
+
+void disable_discard(struct mapped_device *md);
+void disable_write_zeroes(struct mapped_device *md);
+
+static inline sector_t dm_get_size(struct mapped_device *md)
+{
+	return get_capacity(md->disk);
+}
+
+static inline struct dm_stats *dm_get_stats(struct mapped_device *md)
+{
+	return &md->stats;
+}
+
+DECLARE_STATIC_KEY_FALSE(stats_enabled);
+DECLARE_STATIC_KEY_FALSE(swap_bios_enabled);
+DECLARE_STATIC_KEY_FALSE(zoned_enabled);
+
+static inline bool dm_emulate_zone_append(struct mapped_device *md)
+{
+	if (blk_queue_is_zoned(md->queue))
+		return test_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
+	return false;
+}
+
+#define DM_TABLE_MAX_DEPTH 16
+
+struct dm_table {
+	struct mapped_device *md;
+	enum dm_queue_mode type;
+
+	/* btree table */
+	unsigned int depth;
+	unsigned int counts[DM_TABLE_MAX_DEPTH]; /* in nodes */
+	sector_t *index[DM_TABLE_MAX_DEPTH];
+
+	unsigned int num_targets;
+	unsigned int num_allocated;
+	sector_t *highs;
+	struct dm_target *targets;
+
+	struct target_type *immutable_target_type;
+
+	bool integrity_supported:1;
+	bool singleton:1;
+	unsigned integrity_added:1;
+
+	/*
+	 * Indicates the rw permissions for the new logical device.  This
+	 * should be a combination of BLK_OPEN_READ and BLK_OPEN_WRITE.
+	 */
+	blk_mode_t mode;
+
+	/* a list of devices used by this table */
+	struct list_head devices;
+	struct rw_semaphore devices_lock;
+
+	/* events get handed up using this callback */
+	void (*event_fn)(void *data);
+	void *event_context;
+
+	struct dm_md_mempools *mempools;
+
+#ifdef CONFIG_BLK_INLINE_ENCRYPTION
+	struct blk_crypto_profile *crypto_profile;
+#endif
+};
+
+static inline struct dm_target *dm_table_get_target(struct dm_table *t,
+						    unsigned int index)
+{
+	BUG_ON(index >= t->num_targets);
+	return t->targets + index;
+}
+
+/*
+ * One of these is allocated per clone bio.
+ */
+#define DM_TIO_MAGIC 28714
+struct dm_target_io {
+	unsigned short magic;
+	blk_short_t flags;
+	unsigned int target_bio_nr;
+	struct dm_io *io;
+	struct dm_target *ti;
+	unsigned int *len_ptr;
+	sector_t old_sector;
+	struct bio clone;
+};
+#define DM_TARGET_IO_BIO_OFFSET (offsetof(struct dm_target_io, clone))
+#define DM_IO_BIO_OFFSET \
+	(offsetof(struct dm_target_io, clone) + offsetof(struct dm_io, tio))
+
+/*
+ * dm_target_io flags
+ */
+enum {
+	DM_TIO_INSIDE_DM_IO,
+	DM_TIO_IS_DUPLICATE_BIO
+};
+
+static inline bool dm_tio_flagged(struct dm_target_io *tio, unsigned int bit)
+{
+	return (tio->flags & (1U << bit)) != 0;
+}
+
+static inline void dm_tio_set_flag(struct dm_target_io *tio, unsigned int bit)
+{
+	tio->flags |= (1U << bit);
+}
+
+static inline bool dm_tio_is_normal(struct dm_target_io *tio)
+{
+	return (dm_tio_flagged(tio, DM_TIO_INSIDE_DM_IO) &&
+		!dm_tio_flagged(tio, DM_TIO_IS_DUPLICATE_BIO));
+}
+
+/*
+ * One of these is allocated per original bio.
+ * It contains the first clone used for that original.
+ */
+#define DM_IO_MAGIC 19577
+struct dm_io {
+	unsigned short magic;
+	blk_short_t flags;
+	spinlock_t lock;
+	unsigned long start_time;
+	void *data;
+	struct dm_io *next;
+	struct dm_stats_aux stats_aux;
+	blk_status_t status;
+	atomic_t io_count;
+	struct mapped_device *md;
+
+	/* The three fields represent mapped part of original bio */
+	struct bio *orig_bio;
+	unsigned int sector_offset; /* offset to end of orig_bio */
+	unsigned int sectors;
+
+	/* last member of dm_target_io is 'struct bio' */
+	struct dm_target_io tio;
+};
+
+/*
+ * dm_io flags
+ */
+enum {
+	DM_IO_ACCOUNTED,
+	DM_IO_WAS_SPLIT,
+	DM_IO_BLK_STAT
+};
+
+static inline bool dm_io_flagged(struct dm_io *io, unsigned int bit)
+{
+	return (io->flags & (1U << bit)) != 0;
+}
+
+static inline void dm_io_set_flag(struct dm_io *io, unsigned int bit)
+{
+	io->flags |= (1U << bit);
+}
+
+void dm_io_rewind(struct dm_io *io, struct bio_set *bs);
+
+static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
+{
+	return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
+}
+
+unsigned int __dm_get_module_param(unsigned int *module_param, unsigned int def, unsigned int max);
+
+static inline bool dm_message_test_buffer_overflow(char *result, unsigned int maxlen)
+{
+	return !maxlen || strlen(result) + 1 >= maxlen;
+}
+
+extern atomic_t dm_global_event_nr;
+extern wait_queue_head_t dm_global_eventq;
+void dm_issue_global_event(void);
+
+#endif