From b003f4e171304234eae9cc11c9fd7f1cbaaf0d6b Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Sun, 17 Oct 2010 05:18:15 +0000 Subject: CAPI: Silence lockdep warning on get_capi_appl_by_nr usage As long as we hold capi_controller_lock, we can safely access capi_applications without RCU protection as no one can modify the application list underneath us. Introduce an RCU-free __get_capi_appl_by_nr for this purpose. This silences lockdep warnings on suspicious rcu_dereference usage. Signed-off-by: Jan Kiszka Signed-off-by: David S. Miller --- drivers/isdn/capi/kcapi.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) (limited to 'drivers/isdn/capi/kcapi.c') diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c index b054494df846..3acf94cc5acd 100644 --- a/drivers/isdn/capi/kcapi.c +++ b/drivers/isdn/capi/kcapi.c @@ -98,6 +98,16 @@ static inline struct capi_ctr *get_capi_ctr_by_nr(u16 contr) return capi_controller[contr - 1]; } +static inline struct capi20_appl *__get_capi_appl_by_nr(u16 applid) +{ + lockdep_assert_held(&capi_controller_lock); + + if (applid - 1 >= CAPI_MAXAPPL) + return NULL; + + return capi_applications[applid - 1]; +} + static inline struct capi20_appl *get_capi_appl_by_nr(u16 applid) { if (applid - 1 >= CAPI_MAXAPPL) @@ -185,10 +195,9 @@ static void notify_up(u32 contr) ctr->state = CAPI_CTR_RUNNING; for (applid = 1; applid <= CAPI_MAXAPPL; applid++) { - ap = get_capi_appl_by_nr(applid); - if (!ap) - continue; - register_appl(ctr, applid, &ap->rparam); + ap = __get_capi_appl_by_nr(applid); + if (ap) + register_appl(ctr, applid, &ap->rparam); } wake_up_interruptible_all(&ctr->state_wait_queue); @@ -215,7 +224,7 @@ static void ctr_down(struct capi_ctr *ctr, int new_state) memset(ctr->serial, 0, sizeof(ctr->serial)); for (applid = 1; applid <= CAPI_MAXAPPL; applid++) { - ap = get_capi_appl_by_nr(applid); + ap = __get_capi_appl_by_nr(applid); if (ap) capi_ctr_put(ctr); } -- cgit v1.2.3