drivers/mtd/ubi/cdev.c

File Facts

System

Linux kernel

Corpus path

drivers/mtd/ubi/cdev.c

Extension

.c

Size

26048 bytes

Lines

1178

Domain

Driver Families

Bucket

drivers/mtd

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.
• 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/stat.h
• linux/slab.h
• linux/ioctl.h
• linux/capability.h
• linux/uaccess.h
• linux/compat.h
• linux/math64.h
• mtd/ubi-user.h
• ubi.h

Detected Declarations

• function Copyright
• function revoke_exclusive
• function vol_cdev_open
• function vol_cdev_release
• function vol_cdev_llseek
• function vol_cdev_fsync
• function vol_cdev_read
• function vol_cdev_direct_write
• function vol_cdev_write
• function vol_cdev_ioctl
• function verify_mkvol_req
• function verify_rsvol_req
• function rename_volumes
• function list_for_each_entry
• function ubi_get_ec_info
• function ubi_cdev_ioctl
• function ctrl_cdev_ioctl

Annotated Snippet

const struct file_operations ubi_vol_cdev_operations = {
	.owner          = THIS_MODULE,
	.open           = vol_cdev_open,
	.release        = vol_cdev_release,
	.llseek         = vol_cdev_llseek,
	.read           = vol_cdev_read,
	.write          = vol_cdev_write,
	.fsync		= vol_cdev_fsync,
	.unlocked_ioctl = vol_cdev_ioctl,
	.compat_ioctl   = compat_ptr_ioctl,
};

/* UBI character device operations */
const struct file_operations ubi_cdev_operations = {
	.owner          = THIS_MODULE,
	.unlocked_ioctl = ubi_cdev_ioctl,
	.compat_ioctl   = compat_ptr_ioctl,
};

/* UBI control character device operations */
const struct file_operations ubi_ctrl_cdev_operations = {
	.owner          = THIS_MODULE,
	.unlocked_ioctl = ctrl_cdev_ioctl,
	.compat_ioctl   = compat_ptr_ioctl,
};

Annotation

• Immediate include surface: `linux/module.h`, `linux/stat.h`, `linux/slab.h`, `linux/ioctl.h`, `linux/capability.h`, `linux/uaccess.h`, `linux/compat.h`, `linux/math64.h`.
• Detected declarations: `function Copyright`, `function revoke_exclusive`, `function vol_cdev_open`, `function vol_cdev_release`, `function vol_cdev_llseek`, `function vol_cdev_fsync`, `function vol_cdev_read`, `function vol_cdev_direct_write`, `function vol_cdev_write`, `function vol_cdev_ioctl`.
• Atlas domain: Driver Families / drivers/mtd.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• 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.