drivers/md/dm.c

File Facts

System

Linux kernel

Corpus path

drivers/md/dm.c

Extension

.c

Size

92399 bytes

Lines

3840

Domain

Driver Families

Bucket

drivers/md

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• dm-core.h
• dm-rq.h
• dm-uevent.h
• dm-ima.h
• linux/bio-integrity.h
• linux/init.h
• linux/module.h
• linux/mutex.h
• linux/sched/mm.h
• linux/sched/signal.h
• linux/blkpg.h
• linux/bio.h
• linux/mempool.h
• linux/dax.h
• linux/slab.h
• linux/idr.h
• linux/uio.h
• linux/hdreg.h
• linux/delay.h
• linux/wait.h
• linux/pr.h
• linux/refcount.h
• linux/part_stat.h
• linux/blk-crypto.h
• linux/blk-crypto-profile.h

Detected Declarations

• struct clone_info
• struct table_device
• struct dm_blkdev_id
• struct dm_pr
• function dm_issue_global_event
• function dm_bio_get_target_bio_nr
• function get_swap_bios
• function __dm_get_module_param_int
• function __dm_get_module_param
• function dm_get_reserved_bio_based_ios
• function dm_get_numa_node
• function local_init
• function local_exit
• function dm_init
• function dm_exit
• function dm_deleting_md
• function dm_blk_open
• function dm_blk_close
• function dm_open_count
• function dm_lock_for_deletion
• function dm_cancel_deferred_remove
• function do_deferred_remove
• function dm_blk_getgeo
• function dm_prepare_ioctl
• function dm_unprepare_ioctl
• function dm_blk_ioctl
• function dm_start_time_ns_from_clone
• function dm_io_sectors
• function dm_io_acct
• function __dm_start_io_acct
• function dm_start_io_acct
• function dm_end_io_acct
• function free_io
• function free_tio
• function queue_io
• function Everyone
• function dm_put_live_table
• function dm_sync_table
• function dm_put_live_table_fast
• function close_table_device
• function dm_get_table_device
• function dm_put_table_device
• function dm_get_geometry
• function dm_set_geometry
• function __noflush_suspending
• function dm_requeue_add_io
• function dm_kick_requeue
• function dm_handle_requeue

Annotated Snippet

module_init(dm_init);
module_exit(dm_exit);

module_param(major, uint, 0);
MODULE_PARM_DESC(major, "The major number of the device mapper");

module_param(reserved_bio_based_ios, uint, 0644);
MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools");

module_param(dm_numa_node, int, 0644);
MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations");

module_param(swap_bios, int, 0644);
MODULE_PARM_DESC(swap_bios, "Maximum allowed inflight swap IOs");

MODULE_DESCRIPTION(DM_NAME " driver");
MODULE_AUTHOR("Joe Thornber <dm-devel@lists.linux.dev>");
MODULE_LICENSE("GPL");

Annotation

• Immediate include surface: `dm-core.h`, `dm-rq.h`, `dm-uevent.h`, `dm-ima.h`, `linux/bio-integrity.h`, `linux/init.h`, `linux/module.h`, `linux/mutex.h`.
• Detected declarations: `struct clone_info`, `struct table_device`, `struct dm_blkdev_id`, `struct dm_pr`, `function dm_issue_global_event`, `function dm_bio_get_target_bio_nr`, `function get_swap_bios`, `function __dm_get_module_param_int`, `function __dm_get_module_param`, `function dm_get_reserved_bio_based_ios`.
• Atlas domain: Driver Families / drivers/md.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.