drivers/hv/hv_balloon.c

File Facts

System

Linux kernel

Corpus path

drivers/hv/hv_balloon.c

Extension

.c

Size

55029 bytes

Lines

2139

Domain

Driver Families

Bucket

drivers/hv

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/cleanup.h
• linux/kernel.h
• linux/jiffies.h
• linux/mman.h
• linux/debugfs.h
• linux/delay.h
• linux/init.h
• linux/module.h
• linux/slab.h
• linux/kthread.h
• linux/completion.h
• linux/count_zeros.h
• linux/memory_hotplug.h
• linux/memory.h
• linux/notifier.h
• linux/percpu_counter.h
• linux/page_reporting.h
• linux/sizes.h
• linux/hyperv.h
• hyperv/hvhdk.h
• asm/mshyperv.h
• hv_trace_balloon.h

Detected Declarations

• struct dm_header
• struct dm_message
• struct dm_version_request
• struct dm_version_response
• struct dm_capabilities
• struct dm_capabilities_resp_msg
• struct dm_status
• struct dm_balloon
• struct dm_balloon_response
• struct dm_unballoon_request
• struct dm_unballoon_response
• struct dm_hot_add
• struct dm_hot_add_response
• struct dm_info_header
• struct dm_info_msg
• struct hv_hotadd_state
• struct hv_hotadd_gap
• struct balloon_state
• struct hot_add_wrk
• struct hv_dynmem_device
• enum dm_message_type
• enum dm_info_type
• enum hv_dm_state
• function has_pfn_is_backed
• function hv_page_offline_check
• function list_for_each_entry
• function hv_memory_notifier
• function scoped_guard
• function hv_page_online_one
• function hv_bring_pgs_online
• function hv_mem_hot_add
• function scoped_guard
• function scoped_guard
• function hv_online_page
• function scoped_guard
• function pfn_covered
• function handle_pg_range
• function process_hot_add
• function scoped_guard
• function hot_add_req
• function process_info
• function compute_balloon_floor
• function get_pages_committed
• function post_status
• function free_balloon_pages
• function alloc_balloon_pages
• function balloon_up
• function balloon_down

Annotated Snippet

module_init(init_balloon_drv);

MODULE_DESCRIPTION("Hyper-V Balloon");
MODULE_LICENSE("GPL");

Annotation

• Immediate include surface: `linux/cleanup.h`, `linux/kernel.h`, `linux/jiffies.h`, `linux/mman.h`, `linux/debugfs.h`, `linux/delay.h`, `linux/init.h`, `linux/module.h`.
• Detected declarations: `struct dm_header`, `struct dm_message`, `struct dm_version_request`, `struct dm_version_response`, `struct dm_capabilities`, `struct dm_capabilities_resp_msg`, `struct dm_status`, `struct dm_balloon`, `struct dm_balloon_response`, `struct dm_unballoon_request`.
• Atlas domain: Driver Families / drivers/hv.
• 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.