Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / tools / include / asm-generic / hugetlb_encode.h
1 #ifndef _ASM_GENERIC_HUGETLB_ENCODE_H_
2 #define _ASM_GENERIC_HUGETLB_ENCODE_H_
3
4 /*
5  * Several system calls take a flag to request "hugetlb" huge pages.
6  * Without further specification, these system calls will use the
7  * system's default huge page size.  If a system supports multiple
8  * huge page sizes, the desired huge page size can be specified in
9  * bits [26:31] of the flag arguments.  The value in these 6 bits
10  * will encode the log2 of the huge page size.
11  *
12  * The following definitions are associated with this huge page size
13  * encoding in flag arguments.  System call specific header files
14  * that use this encoding should include this file.  They can then
15  * provide definitions based on these with their own specific prefix.
16  * for example:
17  * #define MAP_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT
18  */
19
20 #define HUGETLB_FLAG_ENCODE_SHIFT       26
21 #define HUGETLB_FLAG_ENCODE_MASK        0x3f
22
23 #define HUGETLB_FLAG_ENCODE_64KB        (16 << HUGETLB_FLAG_ENCODE_SHIFT)
24 #define HUGETLB_FLAG_ENCODE_512KB       (19 << HUGETLB_FLAG_ENCODE_SHIFT)
25 #define HUGETLB_FLAG_ENCODE_1MB         (20 << HUGETLB_FLAG_ENCODE_SHIFT)
26 #define HUGETLB_FLAG_ENCODE_2MB         (21 << HUGETLB_FLAG_ENCODE_SHIFT)
27 #define HUGETLB_FLAG_ENCODE_8MB         (23 << HUGETLB_FLAG_ENCODE_SHIFT)
28 #define HUGETLB_FLAG_ENCODE_16MB        (24 << HUGETLB_FLAG_ENCODE_SHIFT)
29 #define HUGETLB_FLAG_ENCODE_256MB       (28 << HUGETLB_FLAG_ENCODE_SHIFT)
30 #define HUGETLB_FLAG_ENCODE_1GB         (30 << HUGETLB_FLAG_ENCODE_SHIFT)
31 #define HUGETLB_FLAG_ENCODE_2GB         (31 << HUGETLB_FLAG_ENCODE_SHIFT)
32 #define HUGETLB_FLAG_ENCODE_16GB        (34 << HUGETLB_FLAG_ENCODE_SHIFT)
33
34 #endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */