Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
+3
-3
drivers/leds/led-class.c
+3
-3
drivers/leds/led-class.c
···
111
write_unlock(&leds_list_lock);
112
113
#ifdef CONFIG_LEDS_TRIGGERS
114
-
rwlock_init(&led_cdev->trigger_lock);
115
116
rc = device_create_file(led_cdev->dev, &dev_attr_trigger);
117
if (rc)
···
147
device_remove_file(led_cdev->dev, &dev_attr_brightness);
148
#ifdef CONFIG_LEDS_TRIGGERS
149
device_remove_file(led_cdev->dev, &dev_attr_trigger);
150
-
write_lock(&led_cdev->trigger_lock);
151
if (led_cdev->trigger)
152
led_trigger_set(led_cdev, NULL);
153
-
write_unlock(&led_cdev->trigger_lock);
154
#endif
155
156
device_unregister(led_cdev->dev);
···
111
write_unlock(&leds_list_lock);
112
113
#ifdef CONFIG_LEDS_TRIGGERS
114
+
init_rwsem(&led_cdev->trigger_lock);
115
116
rc = device_create_file(led_cdev->dev, &dev_attr_trigger);
117
if (rc)
···
147
device_remove_file(led_cdev->dev, &dev_attr_brightness);
148
#ifdef CONFIG_LEDS_TRIGGERS
149
device_remove_file(led_cdev->dev, &dev_attr_trigger);
150
+
down_write(&led_cdev->trigger_lock);
151
if (led_cdev->trigger)
152
led_trigger_set(led_cdev, NULL);
153
+
up_write(&led_cdev->trigger_lock);
154
#endif
155
156
device_unregister(led_cdev->dev);
+25
-24
drivers/leds/led-triggers.c
+25
-24
drivers/leds/led-triggers.c
···
19
#include <linux/device.h>
20
#include <linux/sysdev.h>
21
#include <linux/timer.h>
22
#include <linux/leds.h>
23
#include "leds.h"
24
25
/*
26
* Nests outside led_cdev->trigger_lock
27
*/
28
-
static DEFINE_RWLOCK(triggers_list_lock);
29
static LIST_HEAD(trigger_list);
30
31
ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
···
45
trigger_name[len - 1] = '\0';
46
47
if (!strcmp(trigger_name, "none")) {
48
-
write_lock(&led_cdev->trigger_lock);
49
led_trigger_set(led_cdev, NULL);
50
-
write_unlock(&led_cdev->trigger_lock);
51
return count;
52
}
53
54
-
read_lock(&triggers_list_lock);
55
list_for_each_entry(trig, &trigger_list, next_trig) {
56
if (!strcmp(trigger_name, trig->name)) {
57
-
write_lock(&led_cdev->trigger_lock);
58
led_trigger_set(led_cdev, trig);
59
-
write_unlock(&led_cdev->trigger_lock);
60
61
-
read_unlock(&triggers_list_lock);
62
return count;
63
}
64
}
65
-
read_unlock(&triggers_list_lock);
66
67
return -EINVAL;
68
}
···
75
struct led_trigger *trig;
76
int len = 0;
77
78
-
read_lock(&triggers_list_lock);
79
-
read_lock(&led_cdev->trigger_lock);
80
81
if (!led_cdev->trigger)
82
len += sprintf(buf+len, "[none] ");
···
90
else
91
len += sprintf(buf+len, "%s ", trig->name);
92
}
93
-
read_unlock(&led_cdev->trigger_lock);
94
-
read_unlock(&triggers_list_lock);
95
96
len += sprintf(len+buf, "\n");
97
return len;
···
146
if (!led_cdev->default_trigger)
147
return;
148
149
-
read_lock(&triggers_list_lock);
150
-
write_lock(&led_cdev->trigger_lock);
151
list_for_each_entry(trig, &trigger_list, next_trig) {
152
if (!strcmp(led_cdev->default_trigger, trig->name))
153
led_trigger_set(led_cdev, trig);
154
}
155
-
write_unlock(&led_cdev->trigger_lock);
156
-
read_unlock(&triggers_list_lock);
157
}
158
159
int led_trigger_register(struct led_trigger *trigger)
···
164
INIT_LIST_HEAD(&trigger->led_cdevs);
165
166
/* Add to the list of led triggers */
167
-
write_lock(&triggers_list_lock);
168
list_add_tail(&trigger->next_trig, &trigger_list);
169
-
write_unlock(&triggers_list_lock);
170
171
/* Register with any LEDs that have this as a default trigger */
172
read_lock(&leds_list_lock);
173
list_for_each_entry(led_cdev, &leds_list, node) {
174
-
write_lock(&led_cdev->trigger_lock);
175
if (!led_cdev->trigger && led_cdev->default_trigger &&
176
!strcmp(led_cdev->default_trigger, trigger->name))
177
led_trigger_set(led_cdev, trigger);
178
-
write_unlock(&led_cdev->trigger_lock);
179
}
180
read_unlock(&leds_list_lock);
181
···
207
struct led_classdev *led_cdev;
208
209
/* Remove from the list of led triggers */
210
-
write_lock(&triggers_list_lock);
211
list_del(&trigger->next_trig);
212
-
write_unlock(&triggers_list_lock);
213
214
/* Remove anyone actively using this trigger */
215
read_lock(&leds_list_lock);
216
list_for_each_entry(led_cdev, &leds_list, node) {
217
-
write_lock(&led_cdev->trigger_lock);
218
if (led_cdev->trigger == trigger)
219
led_trigger_set(led_cdev, NULL);
220
-
write_unlock(&led_cdev->trigger_lock);
221
}
222
read_unlock(&leds_list_lock);
223
}
···
19
#include <linux/device.h>
20
#include <linux/sysdev.h>
21
#include <linux/timer.h>
22
+
#include <linux/rwsem.h>
23
#include <linux/leds.h>
24
#include "leds.h"
25
26
/*
27
* Nests outside led_cdev->trigger_lock
28
*/
29
+
static DECLARE_RWSEM(triggers_list_lock);
30
static LIST_HEAD(trigger_list);
31
32
ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr,
···
44
trigger_name[len - 1] = '\0';
45
46
if (!strcmp(trigger_name, "none")) {
47
+
down_write(&led_cdev->trigger_lock);
48
led_trigger_set(led_cdev, NULL);
49
+
up_write(&led_cdev->trigger_lock);
50
return count;
51
}
52
53
+
down_read(&triggers_list_lock);
54
list_for_each_entry(trig, &trigger_list, next_trig) {
55
if (!strcmp(trigger_name, trig->name)) {
56
+
down_write(&led_cdev->trigger_lock);
57
led_trigger_set(led_cdev, trig);
58
+
up_write(&led_cdev->trigger_lock);
59
60
+
up_read(&triggers_list_lock);
61
return count;
62
}
63
}
64
+
up_read(&triggers_list_lock);
65
66
return -EINVAL;
67
}
···
74
struct led_trigger *trig;
75
int len = 0;
76
77
+
down_read(&triggers_list_lock);
78
+
down_read(&led_cdev->trigger_lock);
79
80
if (!led_cdev->trigger)
81
len += sprintf(buf+len, "[none] ");
···
89
else
90
len += sprintf(buf+len, "%s ", trig->name);
91
}
92
+
up_read(&led_cdev->trigger_lock);
93
+
up_read(&triggers_list_lock);
94
95
len += sprintf(len+buf, "\n");
96
return len;
···
145
if (!led_cdev->default_trigger)
146
return;
147
148
+
down_read(&triggers_list_lock);
149
+
down_write(&led_cdev->trigger_lock);
150
list_for_each_entry(trig, &trigger_list, next_trig) {
151
if (!strcmp(led_cdev->default_trigger, trig->name))
152
led_trigger_set(led_cdev, trig);
153
}
154
+
up_write(&led_cdev->trigger_lock);
155
+
up_read(&triggers_list_lock);
156
}
157
158
int led_trigger_register(struct led_trigger *trigger)
···
163
INIT_LIST_HEAD(&trigger->led_cdevs);
164
165
/* Add to the list of led triggers */
166
+
down_write(&triggers_list_lock);
167
list_add_tail(&trigger->next_trig, &trigger_list);
168
+
up_write(&triggers_list_lock);
169
170
/* Register with any LEDs that have this as a default trigger */
171
read_lock(&leds_list_lock);
172
list_for_each_entry(led_cdev, &leds_list, node) {
173
+
down_write(&led_cdev->trigger_lock);
174
if (!led_cdev->trigger && led_cdev->default_trigger &&
175
!strcmp(led_cdev->default_trigger, trigger->name))
176
led_trigger_set(led_cdev, trigger);
177
+
up_write(&led_cdev->trigger_lock);
178
}
179
read_unlock(&leds_list_lock);
180
···
206
struct led_classdev *led_cdev;
207
208
/* Remove from the list of led triggers */
209
+
down_write(&triggers_list_lock);
210
list_del(&trigger->next_trig);
211
+
up_write(&triggers_list_lock);
212
213
/* Remove anyone actively using this trigger */
214
read_lock(&leds_list_lock);
215
list_for_each_entry(led_cdev, &leds_list, node) {
216
+
down_write(&led_cdev->trigger_lock);
217
if (led_cdev->trigger == trigger)
218
led_trigger_set(led_cdev, NULL);
219
+
up_write(&led_cdev->trigger_lock);
220
}
221
read_unlock(&leds_list_lock);
222
}
+2
-1
include/linux/leds.h
+2
-1
include/linux/leds.h
···
14
15
#include <linux/list.h>
16
#include <linux/spinlock.h>
17
+
#include <linux/rwsem.h>
18
19
struct device;
20
/*
···
43
44
#ifdef CONFIG_LEDS_TRIGGERS
45
/* Protects the trigger data below */
46
+
struct rw_semaphore trigger_lock;
47
48
struct led_trigger *trigger;
49
struct list_head trig_list;