>+/*
>+ * Alignment (expressed in log2).  Must be >= log2(PAGE_SIZE) and
>+ * < # bits in a pointer (25 (acorn26), 32 or 64).
>+ */
>+#define	MAP_ALIGNMENT_MASK	0xff000000
>+#define	MAP_ALIGNMENT_SHIFT	24
>+#define	MAP_ALIGNMENT_64KB	0x10000000	/* 2^16 */
>+#define	MAP_ALIGNMENT_16MB	0x18000000	/* 2^24 */
>+#define	MAP_ALIGNMENT_4GB	0x20000000	/* 2^32 */
>+#define	MAP_ALIGNMENT_1TB	0x28000000	/* 2^40 */
>+#define	MAP_ALIGNMENT_256TB	0x30000000	/* 2^48 */
>+#define	MAP_ALIGNMENT_64PB	0x38000000	/* 2^56 */

why not simply

#define	MAP_ALIGNMENT_MASK	0xff000000
#define	MAP_ALIGNMENT_SHIFT	24
#define	MAP_ALIGN(n)		(n<<MAP_ALIGNMENT_SHIFT)
#define	MAP_ALIGNMENT_64KB	MAP_ALIGN(0x08)
#define	MAP_ALIGNMENT_16MB	MAP_ALIGN(0x10)
#define	MAP_ALIGNMENT_4GB	MAP_ALIGN(0x18)
#define	MAP_ALIGNMENT_1TB	MAP_ALIGN(0x20)
#define	MAP_ALIGNMENT_256TB	MAP_ALIGN(0x28)
#define	MAP_ALIGNMENT_64PB	MAP_ALIGN(0x30)

so that someone (nathan?) can request something aligned to 256k via
MAP_ALIGN(0x14)?

-- 
|-----< "CODE WARRIOR" >-----|
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