 @@ -1,173 +1,174 @@
-/*	$NetBSD: pmap_pvt.c,v 1.6 2019/12/18 11:27:56 skrll Exp $	*/
+/*	$NetBSD: pmap_pvt.c,v 1.7 2019/12/28 08:25:33 martin Exp $	*/
 /*-
  * Copyright (c) 2014 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Taylor R. Campbell.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: pmap_pvt.c,v 1.6 2019/12/18 11:27:56 skrll Exp $");
+__RCSID("$NetBSD: pmap_pvt.c,v 1.7 2019/12/28 08:25:33 martin Exp $");
 #include <sys/param.h>
 #include <sys/atomic.h>
 #include <sys/kmem.h>
 #include <sys/pserialize.h>
 #include <uvm/uvm.h>
 #include <uvm/pmap/pmap_pvt.h>
 /*
  * unmanaged pv-tracked ranges
+ *
  * This is a linear list for now because the only user are the DRM
  * graphics drivers, with a single tracked range per device, for the
  * graphics aperture, so there are expected to be few of them.
+ *
  * This is used only after the VM system is initialized well enough
  * that we can use kmem_alloc.
  */
 struct pv_track {
 	paddr_t			pvt_start;
 	psize_t			pvt_size;
 	struct pv_track		*pvt_next;
 	struct pmap_page	pvt_pages[];
 };
 static struct {
 	kmutex_t	lock;
 	pserialize_t	psz;
 	struct pv_track	*list;
 } pv_unmanaged __cacheline_aligned;
 void
 pmap_pv_init(void)
+{
 	mutex_init(&pv_unmanaged.lock, MUTEX_DEFAULT, IPL_NONE);
 	pv_unmanaged.psz = pserialize_create();
 	pv_unmanaged.list = NULL;
+}
 void
 pmap_pv_track(paddr_t start, psize_t size)
+{
 	struct pv_track *pvt;
 	size_t npages;
 	KASSERT(start == trunc_page(start));
 	KASSERT(size == trunc_page(size));
 	/* We may sleep for allocation.  */
 	ASSERT_SLEEPABLE();
 	npages = size >> PAGE_SHIFT;
 	pvt = kmem_zalloc(offsetof(struct pv_track, pvt_pages[npages]),
 	    KM_SLEEP);
 	pvt->pvt_start = start;
 	pvt->pvt_size = size;
 	mutex_enter(&pv_unmanaged.lock);
 	pvt->pvt_next = pv_unmanaged.list;
 	atomic_store_release(&pv_unmanaged.list, pvt);
 	mutex_exit(&pv_unmanaged.lock);
+}
 void
 pmap_pv_untrack(paddr_t start, psize_t size)
+{
 	struct pv_track **pvtp, *pvt;
 	size_t npages;
 	KASSERT(start == trunc_page(start));
 	KASSERT(size == trunc_page(size));
 	/* We may sleep for pserialize_perform.  */
 	ASSERT_SLEEPABLE();
 	mutex_enter(&pv_unmanaged.lock);
 	for (pvtp = &pv_unmanaged.list;
 	     (pvt = *pvtp) != NULL;
 	     pvtp = &pvt->pvt_next) {
 		if (pvt->pvt_start != start)
 			continue;
 		if (pvt->pvt_size != size)
 			panic("pmap_pv_untrack: pv-tracking at 0x%"PRIxPADDR
 			    ": 0x%"PRIxPSIZE" bytes, not 0x%"PRIxPSIZE" bytes",
 			    pvt->pvt_start, pvt->pvt_size, size);
 		/*
 		 * Remove from list.  Readers can safely see the old
 		 * and new states of the list.
 		 */
 		atomic_store_relaxed(pvtp, pvt->pvt_next);
 		/* Wait for readers who can see the old state to finish.  */
 		pserialize_perform(pv_unmanaged.psz);
 		/*
 		 * We now have exclusive access to pvt and can destroy
 		 * it.  Poison it to catch bugs.
 		 */
 		explicit_memset(&pvt->pvt_next, 0x1a, sizeof pvt->pvt_next);
 		goto out;
+	}
 	panic("pmap_pv_untrack: pages not pv-tracked at 0x%"PRIxPADDR
 	    " (0x%"PRIxPSIZE" bytes)",
 	    start, size);
 out:	mutex_exit(&pv_unmanaged.lock);
 	npages = size >> PAGE_SHIFT;
 	kmem_free(pvt, offsetof(struct pv_track, pvt_pages[npages]));
+}
 struct pmap_page *
 pmap_pv_tracked(paddr_t pa)
+{
 	struct pv_track *pvt;
 	size_t pgno;
 	int s;
 	KASSERT(pa == trunc_page(pa));
 	s = pserialize_read_enter();
 	for (pvt = atomic_load_consume(&pv_unmanaged.list);
 	     pvt != NULL;
 	     pvt = pvt->pvt_next) {
 		if ((pvt->pvt_start <= pa) &&
 		    ((pa - pvt->pvt_start) < pvt->pvt_size))
 			break;
+	}
 	pserialize_read_exit(s);
 	if (pvt == NULL)
 		return NULL;
 	KASSERT(pvt->pvt_start <= pa);
 	KASSERT((pa - pvt->pvt_start) < pvt->pvt_size);
 	pgno = (pa - pvt->pvt_start) >> PAGE_SHIFT;
 	return &pvt->pvt_pages[pgno];
+}