bitops/find: clarify and extend documentation

Add return value documentation and clarify the units of the @size
parameter.

Signed-off-by: Cody P Schafer <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: Cody P Schafer <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/asm-generic/bitops/find.h

···
  * @addr: The address to base the search on
  * @offset: The bitnumber to start searching at
  * @size: The bitmap size in bits
+ *
+ * Returns the bit number for the next set bit
+ * If no bits are set, returns @size.
  */
 extern unsigned long find_next_bit(const unsigned long *addr, unsigned long
 		size, unsigned long offset);
···
  * @addr: The address to base the search on
  * @offset: The bitnumber to start searching at
  * @size: The bitmap size in bits
+ *
+ * Returns the bit number of the next zero bit
+ * If no bits are zero, returns @size.
  */
 extern unsigned long find_next_zero_bit(const unsigned long *addr, unsigned
 		long size, unsigned long offset);
···
 /**
  * find_first_bit - find the first set bit in a memory region
  * @addr: The address to start the search at
- * @size: The maximum size to search
+ * @size: The maximum number of bits to search
  *
  * Returns the bit number of the first set bit.
+ * If no bits are set, returns @size.
  */
 extern unsigned long find_first_bit(const unsigned long *addr,
 				    unsigned long size);
···
 /**
  * find_first_zero_bit - find the first cleared bit in a memory region
  * @addr: The address to start the search at
- * @size: The maximum size to search
+ * @size: The maximum number of bits to search
  *
  * Returns the bit number of the first cleared bit.
+ * If no bits are zero, returns @size.
  */
 extern unsigned long find_first_zero_bit(const unsigned long *addr,
 					 unsigned long size);