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UVM_OBJ_WIREPAGES(9)       Kernel Developer's Manual      UVM_OBJ_WIREPAGES(9)

NAME
     uvm_obj_wirepages uvm_obj_unwirepages - temporarily wire pages of a UVM
     object into RAM

SYNOPSIS
     #include <uvm/uvm_extern.h>

     int
     uvm_obj_wirepages(struct uvm_object *uobj, off_t start, off_t end,
         struct pglist *list);

     void
     uvm_obj_unwirepages(struct uvm_object *uobj, off_t start, off_t end);

DESCRIPTION
     uvm_obj_wirepages() temporarily wires a range of pages in a UVM object
     into RAM.  If any pages from start (inclusive) to end (exclusive) are
     currently paged out, it pages them back in first, and arranges that the
     pages in the range will not be paged out until unwired with
     uvm_obj_unwirepages().

     If list is nonnull, it is initialized to a tailq of pages linked through
     the pageq.queue member of struct vm_page, for the convenience of the
     caller.  The caller is not transferred ownership of any part of list and
     need not free anything afterward -- uvm_obj_unwirepages() will free the
     pages when done.

     start and end must be page-aligned.

     Calls to uvm_obj_wirepages() must be matched by uvm_obj_unwirepages()
     with the same range.

     Overlapping ranges may be simultaneously wired; each page may be wired up
     to 2^32 - 1 times, and will not be paged out until all ranges covering it
     have been unwired.

RETURN VALUES
     The uvm_obj_wirepages() function returns zero on success, or returns an
     errno(3) error code and leaves the wired status of all pages unchanged on
     failure.

SEE ALSO
     mlock(3), uvm(9), uvm_map(9)

NetBSD 11.99                     June 14, 2024                    NetBSD 11.99