drivers/md/dm-pcache/dm_pcache.c

File Facts

System

Linux kernel

Corpus path

drivers/md/dm-pcache/dm_pcache.c

Extension

.c

Size

11348 bytes

Lines

498

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

• linux/module.h
• linux/blkdev.h
• linux/bio.h
• ../dm-core.h
• cache_dev.h
• backing_dev.h
• cache.h
• dm_pcache.h

Detected Declarations

• function pcache_defer_reqs_kick
• function defer_req
• function defered_req_fn
• function pcache_req_get
• function end_req
• function pcache_req_put
• function at_least_one_arg
• function parse_cache_dev
• function parse_backing_dev
• function pcache_init_opts
• function parse_cache_opts
• function pcache_start
• function pcache_destroy_args
• function pcache_parse_args
• function dm_pcache_ctr
• function defer_req_stop
• function dm_pcache_dtr
• function dm_pcache_map_bio
• function dm_pcache_status
• function dm_pcache_message
• function dm_pcache_init
• function dm_pcache_exit
• module init dm_pcache_init

Annotated Snippet

module_init(dm_pcache_init);

static void __exit dm_pcache_exit(void)
{
	dm_unregister_target(&dm_pcache_target);
	pcache_cache_exit();
	pcache_backing_exit();
}
module_exit(dm_pcache_exit);

MODULE_DESCRIPTION("dm-pcache Persistent Cache for block device");
MODULE_AUTHOR("Dongsheng Yang <dongsheng.yang@linux.dev>");
MODULE_LICENSE("GPL");

Annotation

• Immediate include surface: `linux/module.h`, `linux/blkdev.h`, `linux/bio.h`, `../dm-core.h`, `cache_dev.h`, `backing_dev.h`, `cache.h`, `dm_pcache.h`.
• Detected declarations: `function pcache_defer_reqs_kick`, `function defer_req`, `function defered_req_fn`, `function pcache_req_get`, `function end_req`, `function pcache_req_put`, `function at_least_one_arg`, `function parse_cache_dev`, `function parse_backing_dev`, `function pcache_init_opts`.
• 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.