DESCRIPTION
The vm_page_io_start function prepares the page for I/O by incrementing its busy flag by one. The vm_page_io_finish function lowers the busy count on the page by one, if the resulting busy count is zero, a wakeup(9) will be issued if the page has been marked PG_WANTED. A page is typically marked PG_WANTED by a thread to register its interest in the page to either complete I/O or becoming available for general use.
AUTHORS
.An -nosplit This manual page was written by
.An Chad David Aq davidc@acns.ab.ca and
.An Alfred Perlstein Aq alfred@FreeBSD.org .
