From fc589a3ce5f38db6239c147da4f9172a25575ecc Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Tue, 30 Oct 2007 17:46:24 -0200 Subject: [PATCH] ACPI: thinkpad-acpi: allow for syscall restart in sysfs handlers Map an mutex_lock_interruptible() error return into ERESTARTSYS, as the only possible error from mutex_lock_interruptible is EINTR, and that will only happen if signal_pending() causes the mutex lock attempt to abort. This still allows signals to be delivered ASAP, which is much nicer than just doing mutex_lock, and still shadows userspace from EINTR when SA_RESTART is active. Problem reported by Peter Jordan. Signed-off-by: Henrique de Moraes Holschuh Cc: Jean Delvare Cc: Peter Jordan Cc: Richard Neill Signed-off-by: Len Brown --- drivers/misc/thinkpad_acpi.c | 40 +++++++++++++++--------------------- 1 file changed, 16 insertions(+), 24 deletions(-) diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c index 251110d0ec80..306daa524c03 100644 --- a/drivers/misc/thinkpad_acpi.c +++ b/drivers/misc/thinkpad_acpi.c @@ -1342,9 +1342,8 @@ static int hotkey_read(char *p) return len; } - res = mutex_lock_interruptible(&hotkey_mutex); - if (res < 0) - return res; + if (mutex_lock_interruptible(&hotkey_mutex)) + return -ERESTARTSYS; res = hotkey_get(&status, &mask); mutex_unlock(&hotkey_mutex); if (res) @@ -1373,9 +1372,8 @@ static int hotkey_write(char *buf) if (!tp_features.hotkey) return -ENODEV; - res = mutex_lock_interruptible(&hotkey_mutex); - if (res < 0) - return res; + if (mutex_lock_interruptible(&hotkey_mutex)) + return -ERESTARTSYS; res = hotkey_get(&status, &mask); if (res) @@ -3768,9 +3766,8 @@ static ssize_t fan_pwm1_store(struct device *dev, /* scale down from 0-255 to 0-7 */ newlevel = (s >> 5) & 0x07; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; rc = fan_get_status(&status); if (!rc && (status & @@ -4020,9 +4017,8 @@ static int fan_get_status_safe(u8 *status) int rc; u8 s; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; rc = fan_get_status(&s); if (!rc) fan_update_desired_level(s); @@ -4156,9 +4152,8 @@ static int fan_set_level_safe(int level) if (!fan_control_allowed) return -EPERM; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; if (level == TPACPI_FAN_LAST_LEVEL) level = fan_control_desired_level; @@ -4179,9 +4174,8 @@ static int fan_set_enable(void) if (!fan_control_allowed) return -EPERM; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; switch (fan_control_access_mode) { case TPACPI_FAN_WR_ACPI_FANS: @@ -4235,9 +4229,8 @@ static int fan_set_disable(void) if (!fan_control_allowed) return -EPERM; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; rc = 0; switch (fan_control_access_mode) { @@ -4274,9 +4267,8 @@ static int fan_set_speed(int speed) if (!fan_control_allowed) return -EPERM; - rc = mutex_lock_interruptible(&fan_mutex); - if (rc < 0) - return rc; + if (mutex_lock_interruptible(&fan_mutex)) + return -ERESTARTSYS; rc = 0; switch (fan_control_access_mode) { -- GitLab