| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Tue, 7 Nov 2017 19:15:59 +0100
From: Thierry Reding <thierry.reding@...il.com>
To: Linus Walleij <linus.walleij@...aro.org>,
Grygorii Strashko <grygorii.strashko@...com>
Cc: Jonathan Hunter <jonathanh@...dia.com>, linux-gpio@...r.kernel.org,
linux-tegra@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v7 15/15] gpio: Automatically add lockdep keys
From: Thierry Reding <treding@...dia.com>
In order to avoid lockdep boilerplate in individual drivers, turn the
gpiochip_add_data() function into a macro that creates a unique class
key for each driver.
Note that this has the slight disadvantage of adding a key for each
driver registered with the system. However, these keys are 8 bytes in
size, which is negligible and a small price to pay for generic
infrastructure.
Suggested-by: Grygorii Strashko <grygorii.strashko@...com>
Signed-off-by: Thierry Reding <treding@...dia.com>
---
drivers/gpio/gpiolib.c | 41 ++++++++++++-----------------------------
include/linux/gpio/driver.h | 36 +++++++++++++++++++++++++++++++++++-
2 files changed, 47 insertions(+), 30 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 35fb13e98d84..f227a2af2314 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -72,7 +72,8 @@ static LIST_HEAD(gpio_lookup_list);
LIST_HEAD(gpio_devices);
static void gpiochip_free_hogs(struct gpio_chip *chip);
-static int gpiochip_add_irqchip(struct gpio_chip *gpiochip);
+static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
+ struct lock_class_key *key);
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);
@@ -1098,30 +1099,8 @@ static void gpiochip_setup_devs(void)
}
}
-/**
- * gpiochip_add_data() - register a gpio_chip
- * @chip: the chip to register, with chip->base initialized
- * @data: driver-private data associated with this chip
- *
- * Context: potentially before irqs will work
- *
- * When gpiochip_add_data() is called very early during boot, so that GPIOs
- * can be freely used, the chip->parent device must be registered before
- * the gpio framework's arch_initcall(). Otherwise sysfs initialization
- * for GPIOs will fail rudely.
- *
- * gpiochip_add_data() must only be called after gpiolib initialization,
- * ie after core_initcall().
- *
- * If chip->base is negative, this requests dynamic assignment of
- * a range of valid GPIOs.
- *
- * Returns:
- * A negative errno if the chip can't be registered, such as because the
- * chip->base is invalid or already associated with a different chip.
- * Otherwise it returns zero as a success code.
- */
-int gpiochip_add_data(struct gpio_chip *chip, void *data)
+int __gpiochip_add_data(struct gpio_chip *chip, void *data,
+ struct lock_class_key *key)
{
unsigned long flags;
int status = 0;
@@ -1267,7 +1246,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
if (status)
goto err_remove_from_list;
- status = gpiochip_add_irqchip(chip);
+ status = gpiochip_add_irqchip(chip, key);
if (status)
goto err_remove_chip;
@@ -1314,7 +1293,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
kfree(gdev);
return status;
}
-EXPORT_SYMBOL_GPL(gpiochip_add_data);
+EXPORT_SYMBOL_GPL(__gpiochip_add_data);
/**
* gpiochip_get_data() - get per-subdriver data for the chip
@@ -1733,8 +1712,10 @@ static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
/**
* gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
* @gpiochip: the GPIO chip to add the IRQ chip to
+ * @lock_key: lockdep class
*/
-static int gpiochip_add_irqchip(struct gpio_chip *gpiochip)
+static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
+ struct lock_class_key *lock_key)
{
struct irq_chip *irqchip = gpiochip->irq.chip;
const struct irq_domain_ops *ops;
@@ -1771,6 +1752,7 @@ static int gpiochip_add_irqchip(struct gpio_chip *gpiochip)
gpiochip->to_irq = gpiochip_to_irq;
gpiochip->irq.default_type = type;
+ gpiochip->irq.lock_key = lock_key;
if (gpiochip->irq.domain_ops)
ops = gpiochip->irq.domain_ops;
@@ -1957,7 +1939,8 @@ EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);
#else /* CONFIG_GPIOLIB_IRQCHIP */
-static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip)
+static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
+ struct lock_dep_class *lock_key)
{
return 0;
}
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 241af05498f9..a6d1a1931e86 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -322,7 +322,41 @@ extern const char *gpiochip_is_requested(struct gpio_chip *chip,
unsigned offset);
/* add/remove chips */
-extern int gpiochip_add_data(struct gpio_chip *chip, void *data);
+extern int __gpiochip_add_data(struct gpio_chip *chip, void *data,
+ struct lock_class_key *lock_key);
+
+/**
+ * gpiochip_add_data() - register a gpio_chip
+ * @chip: the chip to register, with chip->base initialized
+ * @data: driver-private data associated with this chip
+ *
+ * Context: potentially before irqs will work
+ *
+ * When gpiochip_add_data() is called very early during boot, so that GPIOs
+ * can be freely used, the chip->parent device must be registered before
+ * the gpio framework's arch_initcall(). Otherwise sysfs initialization
+ * for GPIOs will fail rudely.
+ *
+ * gpiochip_add_data() must only be called after gpiolib initialization,
+ * ie after core_initcall().
+ *
+ * If chip->base is negative, this requests dynamic assignment of
+ * a range of valid GPIOs.
+ *
+ * Returns:
+ * A negative errno if the chip can't be registered, such as because the
+ * chip->base is invalid or already associated with a different chip.
+ * Otherwise it returns zero as a success code.
+ */
+#ifdef CONFIG_LOCKDEP
+#define gpiochip_add_data(chip, data) ({ \
+ static struct lock_class_key key; \
+ __gpiochip_add_data(chip, data, &key); \
+ })
+#else
+#define gpiochip_add_data(chip, data) __gpiochip_add_data(chip, data, NULL)
+#endif
+
static inline int gpiochip_add(struct gpio_chip *chip)
{
return gpiochip_add_data(chip, NULL);
--
2.14.1
Powered by blists - more mailing lists