mac80211: Re-fix accounting of the tailroom-needed counter

When hw acceleration is enabled, the GENERATE_IV or PUT_IV_SPACE flags
only require headroom space. Therefore, the tailroom-needed counter can
safely be decremented for most drivers.

The older incarnation of this patch (ca34e3b5) assumed that the above
holds true for all drivers. As reported by Christopher Chavez and
researched by Christian Lamparter and Larry Finger, this isn't a valid
assumption for p54 and cw1200.

Drivers that still require tailroom for ICV/MIC even when HW encryption
is enabled can use IEEE80211_KEY_FLAG_RESERVE_TAILROOM to indicate it.

Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Cc: Christopher Chavez <chrischavez@gmx.us>
Cc: Christian Lamparter <chunkeey@googlemail.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Ido Yariv 2015-01-06 08:39:02 -05:00 committed by Johannes Berg
parent 3a4b0c948d
commit db12847ca8
4 changed files with 16 additions and 9 deletions

View file

@ -141,8 +141,7 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
(key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
(key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
sdata->crypto_tx_tailroom_needed_cnt--;
WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
@ -191,8 +190,7 @@ static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
sdata = key->sdata;
if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
(key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
(key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
increment_tailroom_need_count(sdata);
ret = drv_set_key(key->local, DISABLE_KEY, sdata,
@ -889,8 +887,7 @@ void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
(key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
(key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
increment_tailroom_need_count(key->sdata);
}