[src/trunk]: src/sys/arch/amd64/amd64 Make it possible for SVS to map in the ...

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

details:   https://anonhg.NetBSD.org/src/rev/db5d9a946936
branches:  trunk
changeset: 829182:db5d9a946936
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sun Jan 21 08:20:30 2018 +0000

description:
Make it possible for SVS to map in the user page tables a 4K kernel page
contained in a 2MB large page. Will be used soon.

diffstat:

 sys/arch/amd64/amd64/machdep.c |  46 +++++++++++++++++++++++++++++------------
 1 files changed, 32 insertions(+), 14 deletions(-)

diffs (94 lines):

diff -r 04bda14c4b7a -r db5d9a946936 sys/arch/amd64/amd64/machdep.c
--- a/sys/arch/amd64/amd64/machdep.c    Sun Jan 21 04:20:10 2018 +0000
+++ b/sys/arch/amd64/amd64/machdep.c    Sun Jan 21 08:20:30 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machdep.c,v 1.293 2018/01/20 13:42:07 maxv Exp $       */
+/*     $NetBSD: machdep.c,v 1.294 2018/01/21 08:20:30 maxv Exp $       */
 
 /*
  * Copyright (c) 1996, 1997, 1998, 2000, 2006, 2007, 2008, 2011
@@ -110,7 +110,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.293 2018/01/20 13:42:07 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.294 2018/01/21 08:20:30 maxv Exp $");
 
 /* #define XENDEBUG_LOW  */
 
@@ -2278,12 +2278,11 @@
 static pd_entry_t *
 svs_tree_add(struct cpu_info *ci, vaddr_t va)
 {
-       extern pd_entry_t * const normal_pdes[];
        extern const vaddr_t ptp_masks[];
        extern const int ptp_shifts[];
        extern const long nbpd[];
-       pd_entry_t *srcpde, *dstpde;
-       size_t i, idx, pidx, mod;
+       pd_entry_t *dstpde;
+       size_t i, pidx, mod;
        struct vm_page *pg;
        paddr_t pa;
 
@@ -2291,12 +2290,6 @@
        mod = (size_t)-1;
 
        for (i = PTP_LEVELS; i > 1; i--) {
-               idx = pl_i(va, i);
-               srcpde = normal_pdes[i - 2];
-
-               if (!pmap_valid_entry(srcpde[idx])) {
-                       panic("%s: page not mapped", __func__);
-               }
                pidx = pl_i(va % mod, i);
 
                if (!pmap_valid_entry(dstpde[pidx])) {
@@ -2320,19 +2313,44 @@
 static void
 svs_page_add(struct cpu_info *ci, vaddr_t va)
 {
-       pd_entry_t *srcpde, *dstpde;
+       pd_entry_t *srcpde, *dstpde, pde;
        size_t idx, pidx;
+       paddr_t pa;
 
        /* Create levels L4, L3 and L2. */
        dstpde = svs_tree_add(ci, va);
 
-       /* Enter L1. */
+       pidx = pl1_i(va % NBPD_L2);
+
+       /*
+        * If 'va' is in a large page, we need to compute its physical
+        * address manually.
+        */
+       idx = pl2_i(va);
+       srcpde = L2_BASE;
+       if (!pmap_valid_entry(srcpde[idx])) {
+               panic("%s: L2 page not mapped", __func__);
+       }
+       if (srcpde[idx] & PG_PS) {
+               pa = srcpde[idx] & PG_2MFRAME;
+               pa += (paddr_t)(va % NBPD_L2);
+               pde = (srcpde[idx] & ~(PG_PS|PG_2MFRAME)) | pa;
+
+               if (pmap_valid_entry(dstpde[pidx])) {
+                       panic("%s: L1 page already mapped", __func__);
+               }
+               dstpde[pidx] = pde;
+               return;
+       }
+
+       /*
+        * Normal page, just copy the PDE.
+        */
        idx = pl1_i(va);
        srcpde = L1_BASE;
        if (!pmap_valid_entry(srcpde[idx])) {
                panic("%s: L1 page not mapped", __func__);
        }
-       pidx = pl1_i(va % NBPD_L2);
        if (pmap_valid_entry(dstpde[pidx])) {
                panic("%s: L1 page already mapped", __func__);
        }