xref: /qemu/linux-headers/asm-generic/hugetlb_encode.h (revision f670b3eec7f5d1ed8c4573ef244e7b8c6b32001b)
18cf108c5SZhang Yi #ifndef _ASM_GENERIC_HUGETLB_ENCODE_H_
28cf108c5SZhang Yi #define _ASM_GENERIC_HUGETLB_ENCODE_H_
38cf108c5SZhang Yi 
48cf108c5SZhang Yi /*
58cf108c5SZhang Yi  * Several system calls take a flag to request "hugetlb" huge pages.
68cf108c5SZhang Yi  * Without further specification, these system calls will use the
78cf108c5SZhang Yi  * system's default huge page size.  If a system supports multiple
88cf108c5SZhang Yi  * huge page sizes, the desired huge page size can be specified in
98cf108c5SZhang Yi  * bits [26:31] of the flag arguments.  The value in these 6 bits
108cf108c5SZhang Yi  * will encode the log2 of the huge page size.
118cf108c5SZhang Yi  *
128cf108c5SZhang Yi  * The following definitions are associated with this huge page size
138cf108c5SZhang Yi  * encoding in flag arguments.  System call specific header files
148cf108c5SZhang Yi  * that use this encoding should include this file.  They can then
158cf108c5SZhang Yi  * provide definitions based on these with their own specific prefix.
168cf108c5SZhang Yi  * for example:
178cf108c5SZhang Yi  * #define MAP_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT
188cf108c5SZhang Yi  */
198cf108c5SZhang Yi 
208cf108c5SZhang Yi #define HUGETLB_FLAG_ENCODE_SHIFT	26
218cf108c5SZhang Yi #define HUGETLB_FLAG_ENCODE_MASK	0x3f
228cf108c5SZhang Yi 
23*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_16KB	(14U << HUGETLB_FLAG_ENCODE_SHIFT)
24*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_64KB	(16U << HUGETLB_FLAG_ENCODE_SHIFT)
25*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_512KB	(19U << HUGETLB_FLAG_ENCODE_SHIFT)
26*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_1MB		(20U << HUGETLB_FLAG_ENCODE_SHIFT)
27*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_2MB		(21U << HUGETLB_FLAG_ENCODE_SHIFT)
28*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_8MB		(23U << HUGETLB_FLAG_ENCODE_SHIFT)
29*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_16MB	(24U << HUGETLB_FLAG_ENCODE_SHIFT)
30*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_32MB	(25U << HUGETLB_FLAG_ENCODE_SHIFT)
31*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_256MB	(28U << HUGETLB_FLAG_ENCODE_SHIFT)
32*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_512MB	(29U << HUGETLB_FLAG_ENCODE_SHIFT)
33*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_1GB		(30U << HUGETLB_FLAG_ENCODE_SHIFT)
34*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_2GB		(31U << HUGETLB_FLAG_ENCODE_SHIFT)
35*93e0932bSPeter Xu #define HUGETLB_FLAG_ENCODE_16GB	(34U << HUGETLB_FLAG_ENCODE_SHIFT)
368cf108c5SZhang Yi 
378cf108c5SZhang Yi #endif /* _ASM_GENERIC_HUGETLB_ENCODE_H_ */
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