• Johannes Berg's avatar
    mac80211: allow station add/remove to sleep · 34e89507
    Johannes Berg authored
    Many drivers would like to sleep during station
    addition and removal, and currently have a high
    complexity there from not being able to.
    
    This introduces two new callbacks sta_add() and
    sta_remove() that drivers can implement instead
    of using sta_notify() and that can sleep, and
    the new sta_add() callback is also allowed to
    fail.
    
    The reason we didn't do this previously is that
    the IBSS code wants to insert stations from the
    RX path, which is a tasklet, so cannot sleep.
    This patch will keep the station allocation in
    that path, but moves adding the station to the
    driver out of line. Since the addition can now
    fail, we can have IBSS peer structs the driver
    rejected -- in that case we still talk to the
    station but never tell the driver about it in
    the control.sta pointer. If there will ever be
    a driver that has a low limit on the number of
    stations and that cannot talk to any stations
    that are not known to it, we need to do come up
    with a new strategy of handling larger IBSSs,
    maybe quicker expiry or rejecting peers.
    Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
    Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
    34e89507
driver-trace.h 15.2 KB