drivers/usb/gadget/function/rndis.c

Source file repositories/reference/linux-study-clean/drivers/usb/gadget/function/rndis.c

File Facts

System: Linux kernel
Corpus path: drivers/usb/gadget/function/rndis.c
Extension: .c
Size: 29481 bytes
Lines: 1190
Domain: Driver Families
Bucket: drivers/usb
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.
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/moduleparam.h
linux/kernel.h
linux/errno.h
linux/idr.h
linux/list.h
linux/proc_fs.h
linux/slab.h
linux/seq_file.h
linux/netdevice.h
asm/io.h
asm/byteorder.h
linux/unaligned.h
u_rndis.h
rndis.h

Detected Declarations

function gen_ndis_query_resp
function gen_ndis_set_resp
function rndis_init_response
function rndis_query_response
function rndis_set_response
function rndis_reset_response
function rndis_keepalive_response
function rndis_indicate_status_msg
function rndis_signal_connect
function rndis_signal_disconnect
function rndis_uninit
function rndis_set_host_mac
function rndis_msg_parser
function rndis_get_nr
function rndis_put_nr
function rndis_deregister
function rndis_set_param_dev
function rndis_set_param_vendor
function rndis_set_param_medium
function rndis_add_hdr
function rndis_free_response
function rndis_rm_hdr
function rndis_proc_show
function rndis_proc_write
function rndis_proc_open
export rndis_signal_connect
export rndis_signal_disconnect
export rndis_uninit
export rndis_set_host_mac
export rndis_msg_parser
export rndis_register
export rndis_deregister
export rndis_set_param_dev
export rndis_set_param_vendor
export rndis_set_param_medium
export rndis_add_hdr
export rndis_free_response
export rndis_get_next_response
export rndis_rm_hdr

Annotated Snippet

if (params->dev) {
			*outbuf = cpu_to_le32(params->dev->mtu);
			retval = 0;
		}
		break;

	/* mandatory */
	case RNDIS_OID_GEN_LINK_SPEED:
		if (rndis_debug > 1)
			pr_debug("%s: RNDIS_OID_GEN_LINK_SPEED\n", __func__);
		if (params->media_state == RNDIS_MEDIA_STATE_DISCONNECTED)
			*outbuf = cpu_to_le32(0);
		else
			*outbuf = cpu_to_le32(params->speed);
		retval = 0;
		break;

	/* mandatory */
	case RNDIS_OID_GEN_TRANSMIT_BLOCK_SIZE:
		pr_debug("%s: RNDIS_OID_GEN_TRANSMIT_BLOCK_SIZE\n", __func__);
		if (params->dev) {
			*outbuf = cpu_to_le32(params->dev->mtu);
			retval = 0;
		}
		break;

	/* mandatory */
	case RNDIS_OID_GEN_RECEIVE_BLOCK_SIZE:
		pr_debug("%s: RNDIS_OID_GEN_RECEIVE_BLOCK_SIZE\n", __func__);
		if (params->dev) {
			*outbuf = cpu_to_le32(params->dev->mtu);
			retval = 0;
		}
		break;

	/* mandatory */
	case RNDIS_OID_GEN_VENDOR_ID:
		pr_debug("%s: RNDIS_OID_GEN_VENDOR_ID\n", __func__);
		*outbuf = cpu_to_le32(params->vendorID);
		retval = 0;
		break;

	/* mandatory */
	case RNDIS_OID_GEN_VENDOR_DESCRIPTION:
		pr_debug("%s: RNDIS_OID_GEN_VENDOR_DESCRIPTION\n", __func__);
		if (params->vendorDescr) {
			length = strlen(params->vendorDescr);
			memcpy(outbuf, params->vendorDescr, length);
		} else {
			outbuf[0] = 0;
		}
		retval = 0;
		break;

	case RNDIS_OID_GEN_VENDOR_DRIVER_VERSION:
		pr_debug("%s: RNDIS_OID_GEN_VENDOR_DRIVER_VERSION\n", __func__);
		/* Created as LE */
		*outbuf = rndis_driver_version;
		retval = 0;
		break;

	/* mandatory */
	case RNDIS_OID_GEN_CURRENT_PACKET_FILTER:
		pr_debug("%s: RNDIS_OID_GEN_CURRENT_PACKET_FILTER\n", __func__);
		*outbuf = cpu_to_le32(*params->filter);
		retval = 0;
		break;

	/* mandatory */
	case RNDIS_OID_GEN_MAXIMUM_TOTAL_SIZE:
		pr_debug("%s: RNDIS_OID_GEN_MAXIMUM_TOTAL_SIZE\n", __func__);
		*outbuf = cpu_to_le32(RNDIS_MAX_TOTAL_SIZE);
		retval = 0;
		break;

	/* mandatory */
	case RNDIS_OID_GEN_MEDIA_CONNECT_STATUS:
		if (rndis_debug > 1)
			pr_debug("%s: RNDIS_OID_GEN_MEDIA_CONNECT_STATUS\n", __func__);
		*outbuf = cpu_to_le32(params->media_state);
		retval = 0;
		break;

	case RNDIS_OID_GEN_PHYSICAL_MEDIUM:
		pr_debug("%s: RNDIS_OID_GEN_PHYSICAL_MEDIUM\n", __func__);
		*outbuf = cpu_to_le32(0);
		retval = 0;
		break;

	/* The RNDIS specification is incomplete/wrong.   Some versions

Annotation

Immediate include surface: `linux/module.h`, `linux/moduleparam.h`, `linux/kernel.h`, `linux/errno.h`, `linux/idr.h`, `linux/list.h`, `linux/proc_fs.h`, `linux/slab.h`.
Detected declarations: `function gen_ndis_query_resp`, `function gen_ndis_set_resp`, `function rndis_init_response`, `function rndis_query_response`, `function rndis_set_response`, `function rndis_reset_response`, `function rndis_keepalive_response`, `function rndis_indicate_status_msg`, `function rndis_signal_connect`, `function rndis_signal_disconnect`.
Atlas domain: Driver Families / drivers/usb.
Implementation status: integration 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.