NAME    [Toc]    [Back]

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

SYNOPSIS    [Toc]    [Back]

     #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    [Toc]    [Back]

     The vm_page_io_start() function prepares the page for I/O by incrementing
     its busy flag by 1.

     The vm_page_io_finish() function lowers the busy count on the page by
     one, if the resulting busy count is zero, a wakeup will be issued if the
     page has been marked PG_WANTED.  A page is typically marked PG_WANTED by
     a thread to register interested in the page either completing I/O or
     becoming available for general use.

AUTHORS    [Toc]    [Back]

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


FreeBSD 5.2.1			 July 17, 2001			 FreeBSD 5.2.1