xref: /xnu-12377.1.9/libsyscall/mach/mach/vm_page_size.h (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)
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28 
29 #ifndef _VM_PAGE_SIZE_H_
30 #define _VM_PAGE_SIZE_H_
31 
32 #include <Availability.h>
33 #include <mach/mach_types.h>
34 #include <sys/cdefs.h>
35 
36 __BEGIN_DECLS
37 
38 /*
39  *	Globally interesting numbers.
40  *	These macros assume vm_page_size is a power-of-2.
41  */
42 extern  vm_size_t       vm_page_size;
43 extern  vm_size_t       vm_page_mask;
44 extern  int             vm_page_shift;
45 
46 /*
47  *	These macros assume vm_page_size is a power-of-2.
48  */
49 #define trunc_page(x)   ((x) & (~(vm_page_size - 1)))
50 #define round_page(x)   trunc_page((x) + (vm_page_size - 1))
51 
52 /*
53  *	Page-size rounding macros for the fixed-width VM types.
54  */
55 #define mach_vm_trunc_page(x) ((mach_vm_offset_t)(x) & ~((signed)vm_page_mask))
56 #define mach_vm_round_page(x) (((mach_vm_offset_t)(x) + vm_page_mask) & ~((signed)vm_page_mask))
57 
58 
59 extern  vm_size_t       vm_kernel_page_size     __OSX_AVAILABLE_STARTING(__MAC_10_9, __IPHONE_7_0);
60 extern  vm_size_t       vm_kernel_page_mask     __OSX_AVAILABLE_STARTING(__MAC_10_9, __IPHONE_7_0);
61 extern  int             vm_kernel_page_shift    __OSX_AVAILABLE_STARTING(__MAC_10_9, __IPHONE_7_0);
62 
63 #define trunc_page_kernel(x)   ((x) & (~vm_kernel_page_mask))
64 #define round_page_kernel(x)   trunc_page_kernel((x) + vm_kernel_page_mask)
65 
66 __END_DECLS
67 
68 #endif
69