net/mac80211/eht.c

Source file repositories/reference/linux-study-clean/net/mac80211/eht.c

File Facts

System
Linux kernel
Corpus path
net/mac80211/eht.c
Extension
.c
Size
2964 bytes
Lines
103
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: implementation source
Status
source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * EHT handling
 *
 * Copyright(c) 2021-2026 Intel Corporation
 */

#include "driver-ops.h"
#include "ieee80211_i.h"

void
ieee80211_eht_cap_ie_to_sta_eht_cap(struct ieee80211_sub_if_data *sdata,
				    struct ieee80211_supported_band *sband,
				    const u8 *he_cap_ie, u8 he_cap_len,
				    const struct ieee80211_eht_cap_elem *eht_cap_ie_elem,
				    u8 eht_cap_len,
				    struct link_sta_info *link_sta)
{
	struct ieee80211_sta_eht_cap *eht_cap = &link_sta->pub->eht_cap;
	struct ieee80211_he_cap_elem *he_cap_ie_elem = (void *)he_cap_ie;
	u8 eht_ppe_size = 0;
	u8 mcs_nss_size;
	u8 eht_total_size = sizeof(eht_cap->eht_cap_elem);
	u8 *pos = (u8 *)eht_cap_ie_elem;

	memset(eht_cap, 0, sizeof(*eht_cap));

	if (!eht_cap_ie_elem ||
	    !ieee80211_get_eht_iftype_cap_vif(sband, &sdata->vif))
		return;

	mcs_nss_size = ieee80211_eht_mcs_nss_size(he_cap_ie_elem,
						  &eht_cap_ie_elem->fixed,
						  sdata->vif.type ==
							NL80211_IFTYPE_STATION);

	eht_total_size += mcs_nss_size;

	/* Calculate the PPE thresholds length only if the header is present */
	if (eht_cap_ie_elem->fixed.phy_cap_info[5] &
			IEEE80211_EHT_PHY_CAP5_PPE_THRESHOLD_PRESENT) {
		u16 eht_ppe_hdr;

		if (eht_cap_len < eht_total_size + sizeof(u16))
			return;

		eht_ppe_hdr = get_unaligned_le16(eht_cap_ie_elem->optional + mcs_nss_size);
		eht_ppe_size =
			ieee80211_eht_ppe_size(eht_ppe_hdr,
					       eht_cap_ie_elem->fixed.phy_cap_info);
		eht_total_size += eht_ppe_size;

		/* we calculate as if NSS > 8 are valid, but don't handle that */
		if (eht_ppe_size > sizeof(eht_cap->eht_ppe_thres))
			return;
	}

	if (eht_cap_len < eht_total_size)
		return;

	/* Copy the static portion of the EHT capabilities */
	memcpy(&eht_cap->eht_cap_elem, pos, sizeof(eht_cap->eht_cap_elem));
	pos += sizeof(eht_cap->eht_cap_elem);

	/* Copy MCS/NSS which depends on the peer capabilities */
	memset(&eht_cap->eht_mcs_nss_supp, 0,
	       sizeof(eht_cap->eht_mcs_nss_supp));
	memcpy(&eht_cap->eht_mcs_nss_supp, pos, mcs_nss_size);

	if (eht_ppe_size)
		memcpy(eht_cap->eht_ppe_thres,
		       &eht_cap_ie_elem->optional[mcs_nss_size],
		       eht_ppe_size);

	eht_cap->has_eht = true;

	/*
	 * The MPDU length bits are reserved on all but 2.4 GHz and get set via
	 * VHT (5 GHz) or HE (6 GHz) capabilities.
	 */
	if (sband->band != NL80211_BAND_2GHZ)
		return;

	switch (u8_get_bits(eht_cap->eht_cap_elem.mac_cap_info[0],
			    IEEE80211_EHT_MAC_CAP0_MAX_MPDU_LEN_MASK)) {
	case IEEE80211_EHT_MAC_CAP0_MAX_MPDU_LEN_11454:
		link_sta->pub->agg.max_amsdu_len =
			IEEE80211_MAX_MPDU_LEN_VHT_11454;
		break;
	case IEEE80211_EHT_MAC_CAP0_MAX_MPDU_LEN_7991:

Annotation

Implementation Notes