devm_get_free_pages() and devm_free_pages() are the managed counterparts
for __get_free_pages() and free_pages().
Signed-off-by: Eli Billauer <eli.billauer@xxxxxxxxx>
---
Documentation/driver-model/devres.txt | 2 +
drivers/base/devres.c | 76 +++++++++++++++++++++++++++++++++
include/linux/device.h | 4 ++
3 files changed, 82 insertions(+), 0 deletions(-)
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 4999518..e1a2707 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -237,6 +237,8 @@ MEM
devm_kzalloc()
devm_kfree()
devm_kmemdup()
+ devm_get_free_pages()
+ devm_free_pages()
IIO
devm_iio_device_alloc()
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index d0914cb..5230294 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -852,3 +852,79 @@ void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp)
return p;
}
EXPORT_SYMBOL_GPL(devm_kmemdup);
+
+struct pages_devres {
+ unsigned long addr;
+ unsigned int order;
+};
+
+static int devm_pages_match(struct device *dev, void *res, void *p)
+{
+ struct pages_devres *devres = res;
+ struct pages_devres *target = p;
+
+ return devres->addr == target->addr;
+}
+
+static void devm_pages_release(struct device *dev, void *res)
+{
+ struct pages_devres *devres = res;
+
+ free_pages(devres->addr, devres->order);
+}
+
+/**
+ * devm_get_free_pages - Resource-managed __get_free_pages
+ * @dev: Device to allocate memory for
+ * @gfp_mask: Allocation gfp flags
+ * @order: Allocation size is (1 << order) pages
+ *
+ * Managed get_free_pages. Memory allocated with this function is
+ * automatically freed on driver detach.
+ *
+ * RETURNS:
+ * Address of allocated memory on success, 0 on failure.
+ */
+
+unsigned long devm_get_free_pages(struct device *dev,
+ gfp_t gfp_mask, unsigned int order)
+{
+ struct pages_devres *devres;
+ unsigned long addr;
+
+ addr = __get_free_pages(gfp_mask, order);
+
+ if (unlikely(!addr))
+ return 0;
+
+ devres = devres_alloc(devm_pages_release,
+ sizeof(struct pages_devres), GFP_KERNEL);
+ if (unlikely(!devres)) {
+ free_pages(addr, order);
+ return 0;
+ }
+
+ devres->addr = addr;
+ devres->order = order;
+
+ devres_add(dev, devres);
+ return addr;
+}
+EXPORT_SYMBOL_GPL(devm_get_free_pages);
+
+/**
+ * devm_free_pages - Resource-managed free_pages
+ * @dev: Device this memory belongs to
+ * @addr: Memory to free
+ *
+ * Free memory allocated with devm_get_free_pages(). Unlike free_pages,
+ * there is no need to supply the @order.
+ */
+void devm_free_pages(struct device *dev, unsigned long addr)
+{
+ struct pages_devres devres = { .addr = addr };
+
+ WARN_ON(devres_release(dev, devm_pages_release, devm_pages_match,
+ &devres));
+}
+EXPORT_SYMBOL_GPL(devm_free_pages);
diff --git a/include/linux/device.h b/include/linux/device.h
index ab87158..3dc69a2 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -626,6 +626,10 @@ extern char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp);
extern void *devm_kmemdup(struct device *dev, const void *src, size_t len,
gfp_t gfp);
+extern unsigned long devm_get_free_pages(struct device *dev,
+ gfp_t gfp_mask, unsigned int order);
+extern void devm_free_pages(struct device *dev, unsigned long addr);
+
void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
void __iomem *devm_request_and_ioremap(struct device *dev,
struct resource *res);
--
1.7.2.3
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
