diff options
| author | Henrique de Moraes Holschuh <hmh@hmh.eng.br> | 2008-07-21 21:18:20 -0300 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2008-07-29 16:36:35 -0400 |
| commit | 064af1117b4aa64a0e52f6b741df7356ef055142 (patch) | |
| tree | 262651d81f5d390467ee80bca96e403f86bacee3 | |
| parent | f1b23361a0f15497d4c6795a2935b2e98064ddfb (diff) | |
rfkill: mutex fixes
There are two mutexes in rfkill:
rfkill->mutex, which protects some of the fields of a rfkill struct, and is
also used for callback serialization.
rfkill_mutex, which protects the global state, the list of registered
rfkill structs and rfkill->claim.
Make sure to use the correct mutex, and to not miss locking rfkill->mutex
even when we already took rfkill_mutex.
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | net/rfkill/rfkill.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c index fc3a4fd8899..ac205eceaf4 100644 --- a/net/rfkill/rfkill.c +++ b/net/rfkill/rfkill.c @@ -150,7 +150,7 @@ static void update_rfkill_state(struct rfkill *rfkill) * even if the radio is in RFKILL_STATE_HARD_BLOCKED state, so as to * give the driver a hint that it should double-BLOCK the transmitter. * - * Caller must have aquired rfkill_mutex. + * Caller must have acquired rfkill->mutex. */ static int rfkill_toggle_radio(struct rfkill *rfkill, enum rfkill_state state, @@ -216,8 +216,11 @@ void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state) rfkill_states[type] = state; list_for_each_entry(rfkill, &rfkill_list, node) { - if ((!rfkill->user_claim) && (rfkill->type == type)) + if ((!rfkill->user_claim) && (rfkill->type == type)) { + mutex_lock(&rfkill->mutex); rfkill_toggle_radio(rfkill, state, 0); + mutex_unlock(&rfkill->mutex); + } } mutex_unlock(&rfkill_mutex); @@ -228,7 +231,7 @@ EXPORT_SYMBOL(rfkill_switch_all); * rfkill_epo - emergency power off all transmitters * * This kicks all rfkill devices to RFKILL_STATE_SOFT_BLOCKED, ignoring - * everything in its path but rfkill_mutex. + * everything in its path but rfkill_mutex and rfkill->mutex. */ void rfkill_epo(void) { @@ -236,7 +239,9 @@ void rfkill_epo(void) mutex_lock(&rfkill_mutex); list_for_each_entry(rfkill, &rfkill_list, node) { + mutex_lock(&rfkill->mutex); rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1); + mutex_unlock(&rfkill->mutex); } mutex_unlock(&rfkill_mutex); } @@ -372,6 +377,9 @@ static ssize_t rfkill_claim_store(struct device *dev, if (!capable(CAP_NET_ADMIN)) return -EPERM; + if (rfkill->user_claim_unsupported) + return -EOPNOTSUPP; + /* * Take the global lock to make sure the kernel is not in * the middle of rfkill_switch_all @@ -380,19 +388,17 @@ static ssize_t rfkill_claim_store(struct device *dev, if (error) return error; - if (rfkill->user_claim_unsupported) { - error = -EOPNOTSUPP; - goto out_unlock; - } if (rfkill->user_claim != claim) { - if (!claim) + if (!claim) { + mutex_lock(&rfkill->mutex); rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0); + mutex_unlock(&rfkill->mutex); + } rfkill->user_claim = claim; } -out_unlock: mutex_unlock(&rfkill_mutex); return error ? error : count; @@ -521,8 +527,11 @@ static void rfkill_remove_switch(struct rfkill *rfkill) { mutex_lock(&rfkill_mutex); list_del_init(&rfkill->node); - rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1); mutex_unlock(&rfkill_mutex); + + mutex_lock(&rfkill->mutex); + rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1); + mutex_unlock(&rfkill->mutex); } /** |