From 59eb781d2960d68869ede79913d9d57df980efc1 Mon Sep 17 00:00:00 2001 From: "Michael I. Bushnell" Date: Fri, 20 May 1994 19:55:36 +0000 Subject: Initial revision --- libpager/pager-attr.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 libpager/pager-attr.c (limited to 'libpager') diff --git a/libpager/pager-attr.c b/libpager/pager-attr.c new file mode 100644 index 00000000..fd551d01 --- /dev/null +++ b/libpager/pager-attr.c @@ -0,0 +1,75 @@ +/* Changing pager attributes synchronously + Copyright (C) 1994 Free Software Foundation + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2, or (at + your option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "Priv.h" + +/* Change the attributes of the memory object underlying pager P. + Args MAY_CACHE and COPY_STRATEGY are as for + memory_object_change_atributes. Wait for the kernel to report completion + off WAIT is set.*/ +void +pager_change_attributes (struct pager *p, + boolean_t may_cache, + memory_object_copy_strategy_t copy_strategy, + int wait) +{ + struct attribute_request *ar = 0; + + mutex_lock (&p->interlock); + assert (p->pager_state == NORMAL); + + if (wait) + { + for (ar = p->attribute_requests; ar; ar = ar->next) + if (ar->may_cache == may_cache + && ar->copy_strategy == copy_strategy) + { + ar->attrs_pending++; + ar->threads_waiting++; + break; + } + if (!ar) + { + ar = malloc (sizeof (struct attribute_request)); + ar->may_cache = may_cache; + ar->copy_strategy = copy_strategy; + ar->attrs_pending = 1; + ar->threads_waiting = 1; + ar->next = p->attribute_requests; + if (ar->next) + ar->next->prevp = &ar->next; + ar->prevp = &p->attribute_requests; + p->attribute_requests = ar; + } + } + + memory_object_change_attributes (p->memobjcntl, may_cache, copy_strategy, + wait ? p->port.port_right : MACH_PORT_NULL); + + if (wait) + { + while (ar->attrs_pending) + condition_wait (&p->wakeup, &p->interlock); + if (!--ar->threads_waiting) + { + *ar->prevp = ar->next; + free (ar); + } + } + + mutex_unlock (&p->interlock); +} -- cgit v1.2.3