diff options
| author | Jan Kiszka <jan.kiszka@web.de> | 2010-10-17 05:18:15 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-10-21 04:25:49 -0700 |
| commit | b003f4e171304234eae9cc11c9fd7f1cbaaf0d6b (patch) | |
| tree | eb8b14040370ec664c72d8c57fd617a9fe38618f /drivers | |
| parent | 1e253c3b8a1aeed51eef6fc366812f219b97de65 (diff) | |
| download | lwn-b003f4e171304234eae9cc11c9fd7f1cbaaf0d6b.tar.gz lwn-b003f4e171304234eae9cc11c9fd7f1cbaaf0d6b.zip | |
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 <jan.kiszka@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/isdn/capi/kcapi.c | 19 |
1 files changed, 14 insertions, 5 deletions
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); } |