page_size(9v)page_size(9v)NAMEpage_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 transfers
so that they never cross a virtual page boundary. You should use this
global variable only when: A subsystem cannot use the DMA mapping rou‐
tines (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
FILESpage_size(9v)