[src/trunk]: src/sys/dev Add mm_md_page_color hook and use to support better ...

[matt <matt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/cd4c51c08d25
branches:  trunk
changeset: 346391:cd4c51c08d25
user:      matt <matt%NetBSD.org@localhost>
date:      Mon Jul 11 16:13:28 2016 +0000

description:
Add mm_md_page_color hook and use to support better page coloring.

diffstat:

 sys/dev/mm.c |  21 +++++++++++++++------
 sys/dev/mm.h |   8 +++++---
 2 files changed, 20 insertions(+), 9 deletions(-)

diffs (89 lines):

diff -r 5a45a9e8af0f -r cd4c51c08d25 sys/dev/mm.c
--- a/sys/dev/mm.c      Mon Jul 11 16:10:10 2016 +0000
+++ b/sys/dev/mm.c      Mon Jul 11 16:13:28 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mm.c,v 1.20 2016/01/17 23:17:04 christos Exp $ */
+/*     $NetBSD: mm.c,v 1.21 2016/07/11 16:13:28 matt Exp $     */
 
 /*-
  * Copyright (c) 2002, 2008, 2010 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: mm.c,v 1.20 2016/01/17 23:17:04 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: mm.c,v 1.21 2016/07/11 16:13:28 matt Exp $");
 
 #include "opt_compat_netbsd.h"
 
@@ -128,11 +128,11 @@
  * constant, general mapping address otherwise.
  */
 static inline vaddr_t
-dev_mem_getva(paddr_t pa)
+dev_mem_getva(paddr_t pa, int color)
 {
 #ifdef __HAVE_MM_MD_CACHE_ALIASING
        return uvm_km_alloc(kernel_map, PAGE_SIZE,
-           atop(pa) & uvmexp.colormask,
+           color & uvmexp.colormask,
            UVM_KMF_VAONLY | UVM_KMF_WAITVA | UVM_KMF_COLORMATCH);
 #else
        return dev_mem_addr;
@@ -161,6 +161,7 @@
        size_t len, offset;
        bool have_direct;
        int error;
+       int color = 0;
 
        /* Check for wrap around. */
        if ((intptr_t)uio->uio_offset != uio->uio_offset) {
@@ -175,16 +176,24 @@
        offset = uio->uio_offset & PAGE_MASK;
        len = MIN(uio->uio_resid, PAGE_SIZE - offset);
 
+#ifdef __HAVE_MM_MD_CACHE_ALIASING
+       have_direct = mm_md_page_color(paddr, &color);
+#else
+       have_direct = true;
+       color = 0;
+#endif
+
 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
        /* Is physical address directly mapped?  Return VA. */
-       have_direct = mm_md_direct_mapped_phys(paddr, &vaddr);
+       if (have_direct)
+               have_direct = mm_md_direct_mapped_phys(paddr, &vaddr);
 #else
        vaddr = 0;
        have_direct = false;
 #endif
        if (!have_direct) {
                /* Get a special virtual address. */
-               const vaddr_t va = dev_mem_getva(paddr);
+               const vaddr_t va = dev_mem_getva(paddr, color);
 
                /* Map selected KVA to physical address. */
                mutex_enter(&dev_mem_lock);
diff -r 5a45a9e8af0f -r cd4c51c08d25 sys/dev/mm.h
--- a/sys/dev/mm.h      Mon Jul 11 16:10:10 2016 +0000
+++ b/sys/dev/mm.h      Mon Jul 11 16:13:28 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mm.h,v 1.2 2011/06/12 03:35:51 rmind Exp $     */
+/*     $NetBSD: mm.h,v 1.3 2016/07/11 16:13:28 matt Exp $      */
 
 /*-
  * Copyright (c) 2008 Joerg Sonnenberger <joerg%NetBSD.org@localhost>.
@@ -88,8 +88,10 @@
 
 /*
  * Some architectures may need to deal with cache aliasing issues.
- *
- * machine/types.h must define __HAVE_MM_MD_CACHE_ALIASING to note that.
+ * Optional hook to fetch a page's current color and returns whether
+ * that page can be direct mapped.
+ * machine/types.h must define __HAVE_MM_MD_CACHE_ALIASING to use this.
  */
+bool   mm_md_page_color(paddr_t, int *);
 
 #endif /* _SYS_DEV_MM_H_ */