[src/trunk]: src/sys/arch/x86/x86 Add svs_init. This is where we will detect ...

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

details:   https://anonhg.NetBSD.org/src/rev/4e82281af4fa
branches:  trunk
changeset: 829917:4e82281af4fa
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sat Feb 17 17:44:09 2018 +0000

description:
Add svs_init. This is where we will detect the CPU and decide whether
to turn SVS on or not.

Add svs_pgg_update to dynamically add/remove PG_G from all the kernel
pages. Use it now.

diffstat:

 sys/arch/x86/x86/pmap.c        |  10 ++--
 sys/arch/x86/x86/svs.c         |  86 +++++++++++++++++++++++++++++++++++++++++-
 sys/arch/x86/x86/x86_machdep.c |   9 +++-
 3 files changed, 96 insertions(+), 9 deletions(-)

diffs (191 lines):

diff -r 3a81ea7f3f35 -r 4e82281af4fa sys/arch/x86/x86/pmap.c
--- a/sys/arch/x86/x86/pmap.c   Sat Feb 17 16:34:18 2018 +0000
+++ b/sys/arch/x86/x86/pmap.c   Sat Feb 17 17:44:09 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.c,v 1.279 2018/01/20 08:45:28 maxv Exp $  */
+/*     $NetBSD: pmap.c,v 1.280 2018/02/17 17:44:09 maxv Exp $  */
 
 /*
  * Copyright (c) 2008, 2010, 2016, 2017 The NetBSD Foundation, Inc.
@@ -170,7 +170,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.279 2018/01/20 08:45:28 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.280 2018/02/17 17:44:09 maxv Exp $");
 
 #include "opt_user_ldt.h"
 #include "opt_lockdebug.h"
@@ -559,7 +559,7 @@
 #ifdef __HAVE_DIRECT_MAP
 static void pmap_init_directmap(struct pmap *);
 #endif
-#if !defined(XEN) && !defined(SVS)
+#if !defined(XEN)
 static void pmap_remap_global(void);
 #endif
 #ifndef XEN
@@ -1289,7 +1289,7 @@
         * operation of the system.
         */
 
-#if !defined(XEN) && !defined(SVS)
+#if !defined(XEN)
        /*
         * Begin to enable global TLB entries if they are supported.
         * The G bit has no effect until the CR4_PGE bit is set in CR4,
@@ -1655,7 +1655,7 @@
 }
 #endif /* __HAVE_DIRECT_MAP */
 
-#if !defined(XEN) && !defined(SVS)
+#if !defined(XEN)
 /*
  * Remap all of the virtual pages created so far with the PG_G bit.
  */
diff -r 3a81ea7f3f35 -r 4e82281af4fa sys/arch/x86/x86/svs.c
--- a/sys/arch/x86/x86/svs.c    Sat Feb 17 16:34:18 2018 +0000
+++ b/sys/arch/x86/x86/svs.c    Sat Feb 17 17:44:09 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: svs.c,v 1.1 2018/02/11 09:39:37 maxv Exp $     */
+/*     $NetBSD: svs.c,v 1.2 2018/02/17 17:44:09 maxv Exp $     */
 
 /*
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: svs.c,v 1.1 2018/02/11 09:39:37 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: svs.c,v 1.2 2018/02/17 17:44:09 maxv Exp $");
 
 #include "opt_svs.h"
 
@@ -39,6 +39,8 @@
 #include <sys/proc.h>
 #include <sys/cpu.h>
 
+#include <machine/cpuvar.h>
+
 #include <uvm/uvm.h>
 #include <uvm/uvm_page.h>
 
@@ -424,3 +426,83 @@
 
        mutex_exit(&ci->ci_svs_mtx);
 }
+
+static void
+svs_pgg_scanlvl(bool enable, int lvl, vaddr_t *levels)
+{
+       pd_entry_t *pde = (pd_entry_t *)(levels[lvl-1]);
+       pt_entry_t set, rem;
+       size_t i, start;
+       paddr_t pa;
+       int nlvl;
+
+       set = enable ? PG_G : 0;
+       rem = enable ? 0 : PG_G;
+
+       start = (lvl == 4) ? 256 : 0;
+
+       for (i = start; i < 512; i++) {
+               if (!pmap_valid_entry(pde[i])) {
+                       continue;
+               }
+               if (lvl == 1) {
+                       pde[i] = (pde[i] & ~rem) | set;
+               } else if (pde[i] & PG_PS) {
+                       pde[i] = (pde[i] & ~rem) | set;
+               } else {
+                       pa = (paddr_t)(pde[i] & PG_FRAME);
+                       nlvl = lvl - 1;
+
+                       /* remove the previous mapping */
+                       pmap_kremove_local(levels[nlvl-1], PAGE_SIZE);
+
+                       /* kenter the lower level */
+                       pmap_kenter_pa(levels[nlvl-1], pa,
+                           VM_PROT_READ|VM_PROT_WRITE, 0);
+                       pmap_update(pmap_kernel());
+
+                       /* go to the lower level */
+                       svs_pgg_scanlvl(enable, nlvl, levels);
+               }
+       }
+}
+
+static void
+svs_pgg_update(bool enable)
+{
+       const paddr_t pa = pmap_pdirpa(pmap_kernel(), 0);
+       vaddr_t levels[4];
+       size_t i;
+
+       if (!(cpu_feature[0] & CPUID_PGE)) {
+               return;
+       }
+
+       pmap_pg_g = enable ? PG_G : 0;
+
+       for (i = 0; i < 4; i++) {
+               levels[i] = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
+                   UVM_KMF_VAONLY);
+       }
+
+       pmap_kenter_pa(levels[3], pa, VM_PROT_READ|VM_PROT_WRITE, 0);
+       pmap_update(pmap_kernel());
+
+       svs_pgg_scanlvl(enable, 4, levels);
+
+       for (i = 0; i < 4; i++) {
+               pmap_kremove_local(levels[i], PAGE_SIZE);
+               uvm_km_free(kernel_map, levels[i], PAGE_SIZE, UVM_KMF_VAONLY);
+       }
+
+       tlbflushg();
+}
+
+void svs_init(void);
+
+void
+svs_init(void)
+{
+       svs_pgg_update(false);
+}
+
diff -r 3a81ea7f3f35 -r 4e82281af4fa sys/arch/x86/x86/x86_machdep.c
--- a/sys/arch/x86/x86/x86_machdep.c    Sat Feb 17 16:34:18 2018 +0000
+++ b/sys/arch/x86/x86/x86_machdep.c    Sat Feb 17 17:44:09 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: x86_machdep.c,v 1.102 2017/11/23 16:30:50 kamil Exp $  */
+/*     $NetBSD: x86_machdep.c,v 1.103 2018/02/17 17:44:09 maxv Exp $   */
 
 /*-
  * Copyright (c) 2002, 2006, 2007 YAMAMOTO Takashi,
@@ -31,12 +31,13 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: x86_machdep.c,v 1.102 2017/11/23 16:30:50 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: x86_machdep.c,v 1.103 2018/02/17 17:44:09 maxv Exp $");
 
 #include "opt_modular.h"
 #include "opt_physmem.h"
 #include "opt_splash.h"
 #include "opt_kaslr.h"
+#include "opt_svs.h"
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -1090,6 +1091,10 @@
 void
 x86_startup(void)
 {
+#if SVS
+       void svs_init(void);
+       svs_init();
+#endif
 #if !defined(XEN)
        nmi_init();
        pmc_init();