page_size(9v) page_size(9v)
NAME
page_size - Global Variable: Is the virtual page size
SYNOPSIS
extern vm_size_t page_size;
DESCRIPTION
The page_size global variable is the size of a virtual page on a CPU. A device driver can use this global variable to partition I/O trans-
fers so that they never cross a virtual page boundary. You should use this global variable only when: A subsystem cannot use the DMA map-
ping routines (such as, dma_map_alloc, dma_map_load, and so forth) There is a one-to-one correspondence between the system memory map and
the I/O's view of the system memory space
FILES
page_size(9v)
