This RFC implements per CPU caching of AEAD request structures, which allows us to get rid of the per-packet kzalloc/kzfree calls we were forced to introduce to deal with SG API violations, both in the mac80211 and in the core crypto API code.
Since mac80211 only executes the AEAD transforms in softirq context, only one AEAD request can be in flight at the same time on any given CPU, and so, instead of free the request, we can stash its address in a per CPU variable, and reuse it for the next packet. This RFC only addressess CCMP, but GCM and GMAC could be fixed in the same way (and CMAC did not suffer from the API violation issue in the first place) Ard Biesheuvel (2): mac80211: aes_ccm: prepare key struct for storing context data mac80211: aes_ccm: cache AEAD request structures per CPU net/mac80211/aes_ccm.c | 80 +++++++++++++------- net/mac80211/aes_ccm.h | 16 ++-- net/mac80211/key.c | 16 ++-- net/mac80211/key.h | 3 +- net/mac80211/wpa.c | 4 +- 5 files changed, 71 insertions(+), 48 deletions(-) -- 2.7.4
