Kernel Functions for Drivers btop(9F)
NAME
btop - convert size in bytes to size in pages (round down)
SYNOPSIS
#include
unsigned long btop(unsigned long numbytes);
INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI).
PARAMETERS
numbytes Number of bytes.DESCRIPTION
The btop() function returns the number of memory pages that
are contained in the specified number of bytes, with down-
ward rounding in the case that the byte count is not a page multiple. For example, if the page size is 2048, thenbtop(4096) returns 2, and btop(4097) returns 2 as well.
btop(0) returns 0.
RETURN VALUES
The return value is always the number of pages. There are no invalid input values, and therefore no error return values.CONTEXT
The btop() function can be called from user, interrupt, or
kernel context.SEE ALSO
btopr(9F), ddi_btop(9F), ptob(9F)
Writing Device DriversSunOS 5.11 Last change: 16 Jan 2006 1