lib: bitmap: provide devm_bitmap_alloc() and devm_bitmap_zalloc()

Provide managed variants of bitmap_alloc() and bitmap_zalloc().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

include/linux/bitmap.h

@@ -9,6 +9,8 @@
 #include <linux/string.h>
 #include <linux/types.h>
 
+struct device;
+
 /*
  * bitmaps provide bit arrays that consume one or more unsigned
  * longs.  The bitmap interface and available operations are listed
@@ -122,6 +124,12 @@ unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
 unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
 void bitmap_free(const unsigned long *bitmap);
 
+/* Managed variants of the above. */
+unsigned long *devm_bitmap_alloc(struct device *dev,
+				 unsigned int nbits, gfp_t flags);
+unsigned long *devm_bitmap_zalloc(struct device *dev,
+				  unsigned int nbits, gfp_t flags);
+
 /*
  * lib/bitmap.c provides these functions:
  */

lib/bitmap.c

@@ -8,6 +8,7 @@
 #include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/ctype.h>
+#include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/export.h>
 #include <linux/kernel.h>
@@ -1263,6 +1264,38 @@ void bitmap_free(const unsigned long *bitmap)
 }
 EXPORT_SYMBOL(bitmap_free);
 
+static void devm_bitmap_free(void *data)
+{
+	unsigned long *bitmap = data;
+
+	bitmap_free(bitmap);
+}
+
+unsigned long *devm_bitmap_alloc(struct device *dev,
+				 unsigned int nbits, gfp_t flags)
+{
+	unsigned long *bitmap;
+	int ret;
+
+	bitmap = bitmap_alloc(nbits, flags);
+	if (!bitmap)
+		return NULL;
+
+	ret = devm_add_action_or_reset(dev, devm_bitmap_free, bitmap);
+	if (ret)
+		return NULL;
+
+	return bitmap;
+}
+EXPORT_SYMBOL_GPL(devm_bitmap_alloc);
+
+unsigned long *devm_bitmap_zalloc(struct device *dev,
+				  unsigned int nbits, gfp_t flags)
+{
+	return devm_bitmap_alloc(dev, nbits, flags | __GFP_ZERO);
+}
+EXPORT_SYMBOL_GPL(devm_bitmap_zalloc);
+
 #if BITS_PER_LONG == 64
 /**
  * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap