35 lines
1.6 KiB
C
35 lines
1.6 KiB
C
|
#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_ */
|