mac80211: make alignment warning optional

Driver authors should be aware of the alignment requirements, but
not everybody cares about the warning. This patch makes it depend
on a new Kconfig symbol MAC80211_DEBUG_PACKET_ALIGNMENT which can
be enabled regardless of MAC80211_DEBUG and is recommended for
driver authors (only). This also restricts the warning to data
packets so other packets need not be realigned to not trigger the
warning.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg 2008-01-29 16:57:51 +01:00 committed by John W. Linville
parent 24e1c13c93
commit 6feeb8aad7
2 changed files with 19 additions and 0 deletions

View File

@ -98,6 +98,18 @@ config MAC80211_DEBUGFS
Say N unless you know you need this.
config MAC80211_DEBUG_PACKET_ALIGNMENT
bool "Enable packet alignment debugging"
depends on MAC80211
help
This option is recommended for driver authors and strongly
discouraged for everybody else, it will trigger a warning
when a driver hands mac80211 a buffer that is aligned in
a way that will cause problems with the IP stack on some
architectures.
Say N unless you're writing a mac80211 based driver.
config MAC80211_DEBUG
bool "Enable debugging output"
depends on MAC80211

View File

@ -340,11 +340,15 @@ static u32 ieee80211_rx_load_stats(struct ieee80211_local *local,
return load;
}
#ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
static ieee80211_txrx_result
ieee80211_rx_h_verify_ip_alignment(struct ieee80211_txrx_data *rx)
{
int hdrlen;
if (!WLAN_FC_DATA_PRESENT(rx->fc))
return TXRX_CONTINUE;
/*
* Drivers are required to align the payload data in a way that
* guarantees that the contained IP header is aligned to a four-
@ -371,11 +375,14 @@ ieee80211_rx_h_verify_ip_alignment(struct ieee80211_txrx_data *rx)
return TXRX_CONTINUE;
}
#endif
ieee80211_rx_handler ieee80211_rx_pre_handlers[] =
{
ieee80211_rx_h_parse_qos,
#ifdef CONFIG_MAC80211_DEBUG_PACKET_ALIGNMENT
ieee80211_rx_h_verify_ip_alignment,
#endif
NULL
};