drivers/firmware/efi/capsule-loader.c

File Facts

System

Linux kernel

Corpus path

drivers/firmware/efi/capsule-loader.c

Extension

.c

Size

8808 bytes

Lines

343

Domain

Driver Families

Bucket

drivers/firmware

Inferred role

Driver Families: operation-table or driver-model contract

Status

pattern 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.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• 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/kernel.h
• linux/module.h
• linux/miscdevice.h
• linux/highmem.h
• linux/io.h
• linux/slab.h
• linux/mutex.h
• linux/efi.h
• linux/vmalloc.h

Detected Declarations

• function write
• function __efi_capsule_setup_info
• function efi_capsule_setup_info
• function efi_capsule_submit_update
• function efi_capsule_update
• function efi_capsule_release
• function efi_capsule_open
• function efi_capsule_loader_init
• function efi_capsule_loader_exit
• module init efi_capsule_loader_init

Annotated Snippet

static const struct file_operations efi_capsule_fops = {
	.owner = THIS_MODULE,
	.open = efi_capsule_open,
	.write = efi_capsule_write,
	.release = efi_capsule_release,
};

static struct miscdevice efi_capsule_misc = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "efi_capsule_loader",
	.fops = &efi_capsule_fops,
};

static int __init efi_capsule_loader_init(void)
{
	int ret;

	if (!efi_enabled(EFI_RUNTIME_SERVICES))
		return -ENODEV;

	ret = misc_register(&efi_capsule_misc);
	if (ret)
		pr_err("Unable to register capsule loader device\n");

	return ret;
}
module_init(efi_capsule_loader_init);

static void __exit efi_capsule_loader_exit(void)
{
	misc_deregister(&efi_capsule_misc);
}
module_exit(efi_capsule_loader_exit);

MODULE_DESCRIPTION("EFI capsule firmware binary loader");
MODULE_LICENSE("GPL v2");

Annotation

• Immediate include surface: `linux/kernel.h`, `linux/module.h`, `linux/miscdevice.h`, `linux/highmem.h`, `linux/io.h`, `linux/slab.h`, `linux/mutex.h`, `linux/efi.h`.
• Detected declarations: `function write`, `function __efi_capsule_setup_info`, `function efi_capsule_setup_info`, `function efi_capsule_submit_update`, `function efi_capsule_update`, `function efi_capsule_release`, `function efi_capsule_open`, `function efi_capsule_loader_init`, `function efi_capsule_loader_exit`, `module init efi_capsule_loader_init`.
• Atlas domain: Driver Families / drivers/firmware.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.

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.