diff options
authorJoe Perches <joe@perches.com>2014-05-19 14:14:34 +0100
committerMark Brown <broonie@linaro.org>2014-05-19 17:58:52 +0100
commit266a1aedb2d55c3fe9db93c5f6646942d4781cb6 (patch)
parent8bb495e3f02401ee6f76d1b1d77f3ac9f079e376 (diff)
devres: add kernel standard devm_k.alloc functions
Currently, devm_ managed memory only supports kzalloc. Convert the devm_kzalloc implementation to devm_kmalloc and remove the complete memset to 0 but still set the initial struct devres header and whatever padding before data to 0. Add the other normal alloc variants as static inlines with __GFP_ZERO added to the gfp flag where appropriate: devm_kzalloc devm_kcalloc devm_kmalloc_array Add gfp.h to device.h for the newly added static inlines. akpm: the current API forces us to replace kmalloc() with kzalloc() when performing devm_ conversions. This adds a relatively minor overhead. More significantly, it will defeat kmemcheck used-uninitialized checking, and for a particular driver, losing used-uninitialised checking for their core controlling data structures will significantly degrade kmemcheck usefulness. Signed-off-by: Joe Perches <joe@perches.com> Cc: Tejun Heo <tj@kernel.org> Cc: Sangjung Woo <sangjung.woo@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (cherry picked from commit 64c862a839a8db2c02bbaa88b923d13e1208919d) Signed-off-by: Ryan Harkin <ryan.harkin@linaro.org> Signed-off-by: Mark Brown <broonie@linaro.org>
2 files changed, 35 insertions, 13 deletions
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 507379e7b763..37e67a26e388 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -91,7 +91,8 @@ static __always_inline struct devres * alloc_dr(dr_release_t release,
if (unlikely(!dr))
return NULL;
- memset(dr, 0, tot_size);
+ memset(dr, 0, offsetof(struct devres, data));
dr->node.release = release;
return dr;
@@ -745,58 +746,62 @@ void devm_remove_action(struct device *dev, void (*action)(void *), void *data)
- * Managed kzalloc/kfree
+ * Managed kmalloc/kfree
-static void devm_kzalloc_release(struct device *dev, void *res)
+static void devm_kmalloc_release(struct device *dev, void *res)
/* noop */
-static int devm_kzalloc_match(struct device *dev, void *res, void *data)
+static int devm_kmalloc_match(struct device *dev, void *res, void *data)
return res == data;
- * devm_kzalloc - Resource-managed kzalloc
+ * devm_kmalloc - Resource-managed kmalloc
* @dev: Device to allocate memory for
* @size: Allocation size
* @gfp: Allocation gfp flags
- * Managed kzalloc. Memory allocated with this function is
+ * Managed kmalloc. Memory allocated with this function is
* automatically freed on driver detach. Like all other devres
* resources, guaranteed alignment is unsigned long long.
* Pointer to allocated memory on success, NULL on failure.
-void * devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
+void * devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
struct devres *dr;
/* use raw alloc_dr for kmalloc caller tracing */
- dr = alloc_dr(devm_kzalloc_release, size, gfp);
+ dr = alloc_dr(devm_kmalloc_release, size, gfp);
if (unlikely(!dr))
return NULL;
+ /*
+ * This is named devm_kzalloc_release for historical reasons
+ * The initial implementation did not support kmalloc, only kzalloc
+ */
set_node_dbginfo(&dr->node, "devm_kzalloc_release", size);
devres_add(dev, dr->data);
return dr->data;
* devm_kfree - Resource-managed kfree
* @dev: Device this memory belongs to
* @p: Memory to free
- * Free memory allocated with devm_kzalloc().
+ * Free memory allocated with devm_kmalloc().
void devm_kfree(struct device *dev, void *p)
int rc;
- rc = devres_destroy(dev, devm_kzalloc_release, devm_kzalloc_match, p);
+ rc = devres_destroy(dev, devm_kmalloc_release, devm_kmalloc_match, p);
diff --git a/include/linux/device.h b/include/linux/device.h
index c0a126125325..9957dab7477f 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -26,6 +26,7 @@
#include <linux/atomic.h>
#include <linux/ratelimit.h>
#include <linux/uidgid.h>
+#include <linux/gfp.h>
#include <asm/device.h>
struct device;
@@ -568,8 +569,24 @@ extern void devres_close_group(struct device *dev, void *id);
extern void devres_remove_group(struct device *dev, void *id);
extern int devres_release_group(struct device *dev, void *id);
-/* managed kzalloc/kfree for device drivers, no kmalloc, always use kzalloc */
-extern void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp);
+/* managed devm_k.alloc/kfree for device drivers */
+extern void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp);
+static inline void *devm_kzalloc(struct device *dev, size_t size, gfp_t gfp)
+ return devm_kmalloc(dev, size, gfp | __GFP_ZERO);
+static inline void *devm_kmalloc_array(struct device *dev,
+ size_t n, size_t size, gfp_t flags)
+ if (size != 0 && n > SIZE_MAX / size)
+ return NULL;
+ return devm_kmalloc(dev, n * size, flags);
+static inline void *devm_kcalloc(struct device *dev,
+ size_t n, size_t size, gfp_t flags)
+ return devm_kmalloc_array(dev, n, size, flags | __GFP_ZERO);
extern void devm_kfree(struct device *dev, void *p);
void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);