drivers/pci/hotplug/cpqphp_sysfs.c

File Facts

System

Linux kernel

Corpus path

drivers/pci/hotplug/cpqphp_sysfs.c

Extension

.c

Size

4824 bytes

Lines

208

Domain

Representative Device Path

Bucket

PCIe NVMe Storage Path

Inferred role

Representative Device Path: operation-table or driver-model contract

Status

pattern implementation candidate

Why This File Exists

Part of the selected hardware vertical slice: PCI discovery, driver binding, NVMe queues, block requests, DMA, interrupts, and completion.

• Part of the selected hardware vertical slice: PCI discovery, driver binding, NVMe queues, block requests, DMA, interrupts, and completion.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• 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/kernel.h
• linux/slab.h
• linux/types.h
• linux/proc_fs.h
• linux/workqueue.h
• linux/pci.h
• linux/pci_hotplug.h
• linux/mutex.h
• linux/debugfs.h
• cpqphp.h

Detected Declarations

• struct ctrl_dbg
• function show_ctrl
• function show_dev
• function spew_debug_info
• function open
• function lseek
• function read
• function release
• function cpqhp_initialize_debugfs
• function cpqhp_shutdown_debugfs
• function cpqhp_create_debugfs_files
• function cpqhp_remove_debugfs_files

Annotated Snippet

static const struct file_operations debug_ops = {
	.owner = THIS_MODULE,
	.open = open,
	.llseek = lseek,
	.read = read,
	.release = release,
};

static struct dentry *root;

void cpqhp_initialize_debugfs(void)
{
	if (!root)
		root = debugfs_create_dir("cpqhp", NULL);
}

void cpqhp_shutdown_debugfs(void)
{
	debugfs_remove(root);
}

void cpqhp_create_debugfs_files(struct controller *ctrl)
{
	ctrl->dentry = debugfs_create_file(dev_name(&ctrl->pci_dev->dev),
					   S_IRUGO, root, ctrl, &debug_ops);
}

void cpqhp_remove_debugfs_files(struct controller *ctrl)
{
	debugfs_remove(ctrl->dentry);
	ctrl->dentry = NULL;
}

Annotation

• Immediate include surface: `linux/module.h`, `linux/kernel.h`, `linux/slab.h`, `linux/types.h`, `linux/proc_fs.h`, `linux/workqueue.h`, `linux/pci.h`, `linux/pci_hotplug.h`.
• Detected declarations: `struct ctrl_dbg`, `function show_ctrl`, `function show_dev`, `function spew_debug_info`, `function open`, `function lseek`, `function read`, `function release`, `function cpqhp_initialize_debugfs`, `function cpqhp_shutdown_debugfs`.
• Atlas domain: Representative Device Path / PCIe NVMe Storage Path.
• Implementation status: pattern 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.