diff options
| author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-12-07 13:58:19 -0500 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-12-07 13:58:19 -0500 |
| commit | bbce0b5ca2884b44dbfffff77e876a90b4184516 (patch) | |
| tree | 5d2caf13e0f8a7b8e3764f31c29f102c7964adc9 | |
| parent | 5fa2e1591300267b1e082c693d0b4da8e4943551 (diff) | |
| parent | dc47206e552c0850ad11f7e9a1fca0a3c92f5d65 (diff) | |
Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
leds: Fix led trigger locking bugs
| -rw-r--r-- | drivers/leds/led-class.c | 6 | ||||
| -rw-r--r-- | drivers/leds/led-triggers.c | 49 | ||||
| -rw-r--r-- | include/linux/leds.h | 3 |
3 files changed, 30 insertions, 28 deletions
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 4211293ce862..ba8b04b03b9f 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c | |||
| @@ -111,7 +111,7 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev) | |||
| 111 | write_unlock(&leds_list_lock); | 111 | write_unlock(&leds_list_lock); |
| 112 | 112 | ||
| 113 | #ifdef CONFIG_LEDS_TRIGGERS | 113 | #ifdef CONFIG_LEDS_TRIGGERS |
| 114 | rwlock_init(&led_cdev->trigger_lock); | 114 | init_rwsem(&led_cdev->trigger_lock); |
| 115 | 115 | ||
| 116 | rc = device_create_file(led_cdev->dev, &dev_attr_trigger); | 116 | rc = device_create_file(led_cdev->dev, &dev_attr_trigger); |
| 117 | if (rc) | 117 | if (rc) |
| @@ -147,10 +147,10 @@ void led_classdev_unregister(struct led_classdev *led_cdev) | |||
| 147 | device_remove_file(led_cdev->dev, &dev_attr_brightness); | 147 | device_remove_file(led_cdev->dev, &dev_attr_brightness); |
| 148 | #ifdef CONFIG_LEDS_TRIGGERS | 148 | #ifdef CONFIG_LEDS_TRIGGERS |
| 149 | device_remove_file(led_cdev->dev, &dev_attr_trigger); | 149 | device_remove_file(led_cdev->dev, &dev_attr_trigger); |
| 150 | write_lock(&led_cdev->trigger_lock); | 150 | down_write(&led_cdev->trigger_lock); |
| 151 | if (led_cdev->trigger) | 151 | if (led_cdev->trigger) |
| 152 | led_trigger_set(led_cdev, NULL); | 152 | led_trigger_set(led_cdev, NULL); |
| 153 | write_unlock(&led_cdev->trigger_lock); | 153 | up_write(&led_cdev->trigger_lock); |
| 154 | #endif | 154 | #endif |
| 155 | 155 | ||
| 156 | device_unregister(led_cdev->dev); | 156 | device_unregister(led_cdev->dev); |
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 575368c2b100..0bdb786210b1 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c | |||
| @@ -19,13 +19,14 @@ | |||
| 19 | #include <linux/device.h> | 19 | #include <linux/device.h> |
| 20 | #include <linux/sysdev.h> | 20 | #include <linux/sysdev.h> |
| 21 | #include <linux/timer.h> | 21 | #include <linux/timer.h> |
| 22 | #include <linux/rwsem.h> | ||
| 22 | #include <linux/leds.h> | 23 | #include <linux/leds.h> |
| 23 | #include "leds.h" | 24 | #include "leds.h" |
| 24 | 25 | ||
| 25 | /* | 26 | /* |
| 26 | * Nests outside led_cdev->trigger_lock | 27 | * Nests outside led_cdev->trigger_lock |
| 27 | */ | 28 | */ |
| 28 | static DEFINE_RWLOCK(triggers_list_lock); | 29 | static DECLARE_RWSEM(triggers_list_lock); |
| 29 | static LIST_HEAD(trigger_list); | 30 | static LIST_HEAD(trigger_list); |
| 30 | 31 | ||
| 31 | ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, | 32 | ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, |
| @@ -44,24 +45,24 @@ ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, | |||
| 44 | trigger_name[len - 1] = '\0'; | 45 | trigger_name[len - 1] = '\0'; |
| 45 | 46 | ||
| 46 | if (!strcmp(trigger_name, "none")) { | 47 | if (!strcmp(trigger_name, "none")) { |
| 47 | write_lock(&led_cdev->trigger_lock); | 48 | down_write(&led_cdev->trigger_lock); |
| 48 | led_trigger_set(led_cdev, NULL); | 49 | led_trigger_set(led_cdev, NULL); |
| 49 | write_unlock(&led_cdev->trigger_lock); | 50 | up_write(&led_cdev->trigger_lock); |
| 50 | return count; | 51 | return count; |
| 51 | } | 52 | } |
| 52 | 53 | ||
| 53 | read_lock(&triggers_list_lock); | 54 | down_read(&triggers_list_lock); |
| 54 | list_for_each_entry(trig, &trigger_list, next_trig) { | 55 | list_for_each_entry(trig, &trigger_list, next_trig) { |
| 55 | if (!strcmp(trigger_name, trig->name)) { | 56 | if (!strcmp(trigger_name, trig->name)) { |
| 56 | write_lock(&led_cdev->trigger_lock); | 57 | down_write(&led_cdev->trigger_lock); |
| 57 | led_trigger_set(led_cdev, trig); | 58 | led_trigger_set(led_cdev, trig); |
| 58 | write_unlock(&led_cdev->trigger_lock); | 59 | up_write(&led_cdev->trigger_lock); |
| 59 | 60 | ||
| 60 | read_unlock(&triggers_list_lock); | 61 | up_read(&triggers_list_lock); |
| 61 | return count; | 62 | return count; |
| 62 | } | 63 | } |
| 63 | } | 64 | } |
| 64 | read_unlock(&triggers_list_lock); | 65 | up_read(&triggers_list_lock); |
| 65 | 66 | ||
| 66 | return -EINVAL; | 67 | return -EINVAL; |
| 67 | } | 68 | } |
| @@ -74,8 +75,8 @@ ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, | |||
| 74 | struct led_trigger *trig; | 75 | struct led_trigger *trig; |
| 75 | int len = 0; | 76 | int len = 0; |
| 76 | 77 | ||
| 77 | read_lock(&triggers_list_lock); | 78 | down_read(&triggers_list_lock); |
| 78 | read_lock(&led_cdev->trigger_lock); | 79 | down_read(&led_cdev->trigger_lock); |
| 79 | 80 | ||
| 80 | if (!led_cdev->trigger) | 81 | if (!led_cdev->trigger) |
| 81 | len += sprintf(buf+len, "[none] "); | 82 | len += sprintf(buf+len, "[none] "); |
| @@ -89,8 +90,8 @@ ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, | |||
| 89 | else | 90 | else |
| 90 | len += sprintf(buf+len, "%s ", trig->name); | 91 | len += sprintf(buf+len, "%s ", trig->name); |
| 91 | } | 92 | } |
| 92 | read_unlock(&led_cdev->trigger_lock); | 93 | up_read(&led_cdev->trigger_lock); |
| 93 | read_unlock(&triggers_list_lock); | 94 | up_read(&triggers_list_lock); |
| 94 | 95 | ||
| 95 | len += sprintf(len+buf, "\n"); | 96 | len += sprintf(len+buf, "\n"); |
| 96 | return len; | 97 | return len; |
| @@ -145,14 +146,14 @@ void led_trigger_set_default(struct led_classdev *led_cdev) | |||
| 145 | if (!led_cdev->default_trigger) | 146 | if (!led_cdev->default_trigger) |
| 146 | return; | 147 | return; |
| 147 | 148 | ||
| 148 | read_lock(&triggers_list_lock); | 149 | down_read(&triggers_list_lock); |
| 149 | write_lock(&led_cdev->trigger_lock); | 150 | down_write(&led_cdev->trigger_lock); |
| 150 | list_for_each_entry(trig, &trigger_list, next_trig) { | 151 | list_for_each_entry(trig, &trigger_list, next_trig) { |
| 151 | if (!strcmp(led_cdev->default_trigger, trig->name)) | 152 | if (!strcmp(led_cdev->default_trigger, trig->name)) |
| 152 | led_trigger_set(led_cdev, trig); | 153 | led_trigger_set(led_cdev, trig); |
| 153 | } | 154 | } |
| 154 | write_unlock(&led_cdev->trigger_lock); | 155 | up_write(&led_cdev->trigger_lock); |
| 155 | read_unlock(&triggers_list_lock); | 156 | up_read(&triggers_list_lock); |
| 156 | } | 157 | } |
| 157 | 158 | ||
| 158 | int led_trigger_register(struct led_trigger *trigger) | 159 | int led_trigger_register(struct led_trigger *trigger) |
| @@ -163,18 +164,18 @@ int led_trigger_register(struct led_trigger *trigger) | |||
| 163 | INIT_LIST_HEAD(&trigger->led_cdevs); | 164 | INIT_LIST_HEAD(&trigger->led_cdevs); |
| 164 | 165 | ||
| 165 | /* Add to the list of led triggers */ | 166 | /* Add to the list of led triggers */ |
| 166 | write_lock(&triggers_list_lock); | 167 | down_write(&triggers_list_lock); |
| 167 | list_add_tail(&trigger->next_trig, &trigger_list); | 168 | list_add_tail(&trigger->next_trig, &trigger_list); |
| 168 | write_unlock(&triggers_list_lock); | 169 | up_write(&triggers_list_lock); |
| 169 | 170 | ||
| 170 | /* Register with any LEDs that have this as a default trigger */ | 171 | /* Register with any LEDs that have this as a default trigger */ |
| 171 | read_lock(&leds_list_lock); | 172 | read_lock(&leds_list_lock); |
| 172 | list_for_each_entry(led_cdev, &leds_list, node) { | 173 | list_for_each_entry(led_cdev, &leds_list, node) { |
| 173 | write_lock(&led_cdev->trigger_lock); | 174 | down_write(&led_cdev->trigger_lock); |
| 174 | if (!led_cdev->trigger && led_cdev->default_trigger && | 175 | if (!led_cdev->trigger && led_cdev->default_trigger && |
| 175 | !strcmp(led_cdev->default_trigger, trigger->name)) | 176 | !strcmp(led_cdev->default_trigger, trigger->name)) |
| 176 | led_trigger_set(led_cdev, trigger); | 177 | led_trigger_set(led_cdev, trigger); |
| 177 | write_unlock(&led_cdev->trigger_lock); | 178 | up_write(&led_cdev->trigger_lock); |
| 178 | } | 179 | } |
| 179 | read_unlock(&leds_list_lock); | 180 | read_unlock(&leds_list_lock); |
| 180 | 181 | ||
| @@ -206,17 +207,17 @@ void led_trigger_unregister(struct led_trigger *trigger) | |||
| 206 | struct led_classdev *led_cdev; | 207 | struct led_classdev *led_cdev; |
| 207 | 208 | ||
| 208 | /* Remove from the list of led triggers */ | 209 | /* Remove from the list of led triggers */ |
| 209 | write_lock(&triggers_list_lock); | 210 | down_write(&triggers_list_lock); |
| 210 | list_del(&trigger->next_trig); | 211 | list_del(&trigger->next_trig); |
| 211 | write_unlock(&triggers_list_lock); | 212 | up_write(&triggers_list_lock); |
| 212 | 213 | ||
| 213 | /* Remove anyone actively using this trigger */ | 214 | /* Remove anyone actively using this trigger */ |
| 214 | read_lock(&leds_list_lock); | 215 | read_lock(&leds_list_lock); |
| 215 | list_for_each_entry(led_cdev, &leds_list, node) { | 216 | list_for_each_entry(led_cdev, &leds_list, node) { |
| 216 | write_lock(&led_cdev->trigger_lock); | 217 | down_write(&led_cdev->trigger_lock); |
| 217 | if (led_cdev->trigger == trigger) | 218 | if (led_cdev->trigger == trigger) |
| 218 | led_trigger_set(led_cdev, NULL); | 219 | led_trigger_set(led_cdev, NULL); |
| 219 | write_unlock(&led_cdev->trigger_lock); | 220 | up_write(&led_cdev->trigger_lock); |
| 220 | } | 221 | } |
| 221 | read_unlock(&leds_list_lock); | 222 | read_unlock(&leds_list_lock); |
| 222 | } | 223 | } |
diff --git a/include/linux/leds.h b/include/linux/leds.h index dc1178f6184b..b4130ff58d0c 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h | |||
| @@ -14,6 +14,7 @@ | |||
| 14 | 14 | ||
| 15 | #include <linux/list.h> | 15 | #include <linux/list.h> |
| 16 | #include <linux/spinlock.h> | 16 | #include <linux/spinlock.h> |
| 17 | #include <linux/rwsem.h> | ||
| 17 | 18 | ||
| 18 | struct device; | 19 | struct device; |
| 19 | /* | 20 | /* |
| @@ -43,7 +44,7 @@ struct led_classdev { | |||
| 43 | 44 | ||
| 44 | #ifdef CONFIG_LEDS_TRIGGERS | 45 | #ifdef CONFIG_LEDS_TRIGGERS |
| 45 | /* Protects the trigger data below */ | 46 | /* Protects the trigger data below */ |
| 46 | rwlock_t trigger_lock; | 47 | struct rw_semaphore trigger_lock; |
| 47 | 48 | ||
| 48 | struct led_trigger *trigger; | 49 | struct led_trigger *trigger; |
| 49 | struct list_head trig_list; | 50 | struct list_head trig_list; |
