/* 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
#define DM_MAX_TARGETS 1048576
#define DM_MAX_TARGET_PARAMS 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;
void *zone_revalidate_map;
#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;
/* set if all the targets in the table have "flush_bypasses_map" set */
bool flush_bypasses_map: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
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