NAME

       vm_page_io_start, vm_page_io_finish — ready or unready a page for I/O

SYNOPSIS

       #include <sys/param.h>
       #include <vm/vm.h>
       #include <vm/vm_page.h>

       void
       vm_page_io_start(vm_page_t m);

       void
       vm_page_io_finish(vm_page_t m);

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 VPO_WANTED.  A page is typically marked
       VPO_WANTED by a thread to register its interest in the page to either complete I/O or becoming  available
       for general use.

AUTHORS

       This manual page was written by Chad David <davidc@acns.ab.ca> and Alfred Perlstein <alfred@FreeBSD.org>.

Debian                                            July 17, 2001                              VM_PAGE_IO_START(9)