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- #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_64KB (16 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_512KB (19 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_1MB (20 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_2MB (21 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_8MB (23 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_16MB (24 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_256MB (28 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_1GB (30 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_2GB (31 << HUGETLB_FLAG_ENCODE_SHIFT)
- #define HUGETLB_FLAG_ENCODE_16GB (34 << HUGETLB_FLAG_ENCODE_SHIFT)
- #endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */
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