#ifndef _ASM_GENERIC_HUGETLB_ENCODE_H_
#define _ASM_GENERIC_HUGETLB_ENCODE_H_

/*
 * Several system calls take a flag to request "hugetlb" huge pages.
 * Without further specification, these system calls will use the
 * system's default huge page size.  If a system supports multiple
 * huge page sizes, the desired huge page size can be specified in
 * bits [26:31] of the flag arguments.  The value in these 6 bits
 * will encode the log2 of the huge page size.
 *
 * The following definitions are associated with this huge page size
 * encoding in flag arguments.  System call specific header files
 * that use this encoding should include this file.  They can then
 * provide definitions based on these with their own specific prefix.
 * for example:
 * #define MAP_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT
 */

#define HUGETLB_FLAG_ENCODE_SHIFT       26
#define HUGETLB_FLAG_ENCODE_MASK        0x3f

#define HUGETLB_FLAG_ENCODE_16KB        (14U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_64KB        (16U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_512KB       (19U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_1MB         (20U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_2MB         (21U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_8MB         (23U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_16MB        (24U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_32MB        (25U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_256MB       (28U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_512MB       (29U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_1GB         (30U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_2GB         (31U << HUGETLB_FLAG_ENCODE_SHIFT)
#define HUGETLB_FLAG_ENCODE_16GB        (34U << HUGETLB_FLAG_ENCODE_SHIFT)

#endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */