Module Name: src
Committed By: maxv
Date: Sun Jul 29 08:02:25 UTC 2018
Modified Files:
src/sys/arch/xen/x86: x86_xpmap.c
Log Message:
Reduce the confusion, rename a bunch of variables and reorg a little.
Tested on i386PAE-domU and amd64-dom0.
To generate a diff of this commit:
cvs rdiff -u -r1.80 -r1.81 src/sys/arch/xen/x86/x86_xpmap.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/xen/x86/x86_xpmap.c
diff -u src/sys/arch/xen/x86/x86_xpmap.c:1.80 src/sys/arch/xen/x86/x86_xpmap.c:1.81
--- src/sys/arch/xen/x86/x86_xpmap.c:1.80 Fri Jul 27 10:04:22 2018
+++ src/sys/arch/xen/x86/x86_xpmap.c Sun Jul 29 08:02:24 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: x86_xpmap.c,v 1.80 2018/07/27 10:04:22 maxv Exp $ */
+/* $NetBSD: x86_xpmap.c,v 1.81 2018/07/29 08:02:24 maxv Exp $ */
/*
* Copyright (c) 2017 The NetBSD Foundation, Inc.
@@ -95,7 +95,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: x86_xpmap.c,v 1.80 2018/07/27 10:04:22 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: x86_xpmap.c,v 1.81 2018/07/29 08:02:24 maxv Exp $");
#include "opt_xen.h"
#include "opt_ddb.h"
@@ -451,11 +451,10 @@ xpq_update_foreign(paddr_t ptr, pt_entry
#define PDIRSZ PTP_LEVELS
#else
/*
- * For PAE, we consider a single contiguous L2 "superpage" of 4 pages, all of
- * them mapped by the L3 page. We also need a shadow page for L3[3].
- * XXX so why 6?
+ * For PAE, we need an L3 page, a single contiguous L2 "superpage" of 4 pages
+ * (all of them mapped by the L3 page), and a shadow page for L3[3].
*/
-#define PDIRSZ 6
+#define PDIRSZ (1 + 4 + 1)
#endif
/*
@@ -595,7 +594,7 @@ bootstrap_again:
/*
* Build a new table and switch to it.
- * old_count is # of old tables (including PGD, PDTPE and PDE).
+ * old_count is # of old tables (including L4, L3 and L2).
* new_count is # of new tables (PTE only).
* We assume the areas don't overlap.
*/
@@ -603,8 +602,7 @@ static void
xen_bootstrap_tables(vaddr_t old_pgd, vaddr_t new_pgd, size_t old_count,
size_t new_count, bool final)
{
- pd_entry_t *pdtpe, *pde, *pte;
- pd_entry_t *bt_pgd;
+ pd_entry_t *L4cpu, *L4, *L3, *L2, *pte;
paddr_t addr;
vaddr_t page, avail, map_end;
int i;
@@ -659,68 +657,73 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
__PRINTK(("console %#lx ", xen_start_info.console_mfn));
__PRINTK(("xenstore %#" PRIx32 "\n", xen_start_info.store_mfn));
+ avail = new_pgd;
+
/*
- * Create bootstrap page tables. What we need:
- * - a PGD (level 4)
- * - a PDTPE (level 3)
- * - a PDE (level 2)
- * - some PTEs (level 1)
- */
-
- bt_pgd = (pd_entry_t *)new_pgd;
- memset(bt_pgd, 0, PAGE_SIZE);
- avail = new_pgd + PAGE_SIZE;
-
-#ifdef __x86_64__
- /* Per-cpu L4 */
- pd_entry_t *bt_cpu_pgd = bt_pgd;
- /* pmap_kernel() "shadow" L4 */
- bt_pgd = (pd_entry_t *)avail;
- memset(bt_pgd, 0, PAGE_SIZE);
+ * Create our page tables.
+ */
+
+#ifdef __x86_64__
+ /* per-cpu L4 */
+ L4cpu = (pd_entry_t *)avail;
+ memset(L4cpu, 0, PAGE_SIZE);
avail += PAGE_SIZE;
- /* Install L3 */
- pdtpe = (pd_entry_t *)avail;
- memset(pdtpe, 0, PAGE_SIZE);
+ /* pmap_kernel L4 */
+ L4 = (pd_entry_t *)avail;
+ memset(L4, 0, PAGE_SIZE);
avail += PAGE_SIZE;
- addr = ((u_long)pdtpe) - KERNBASE;
- bt_pgd[pl4_pi(KERNTEXTOFF)] = bt_cpu_pgd[pl4_pi(KERNTEXTOFF)] =
- xpmap_ptom_masked(addr) | PG_V | PG_RW;
-
- /* Level 2 */
- pde = (pd_entry_t *)avail;
- memset(pde, 0, PAGE_SIZE);
+ /* L3 */
+ L3 = (pd_entry_t *)avail;
+ memset(L3, 0, PAGE_SIZE);
avail += PAGE_SIZE;
- addr = ((u_long)pde) - KERNBASE;
- pdtpe[pl3_pi(KERNTEXTOFF)] =
- xpmap_ptom_masked(addr) | PG_V | PG_RW;
-#else
- pdtpe = bt_pgd;
+ /* link L4->L3 */
+ addr = ((u_long)L3) - KERNBASE;
+ L4cpu[pl4_pi(KERNTEXTOFF)] = xpmap_ptom_masked(addr) | PG_V | PG_RW;
+ L4[pl4_pi(KERNTEXTOFF)] = xpmap_ptom_masked(addr) | PG_V | PG_RW;
+
+ /* L2 */
+ L2 = (pd_entry_t *)avail;
+ memset(L2, 0, PAGE_SIZE);
+ avail += PAGE_SIZE;
+
+ /* link L3->L2 */
+ addr = ((u_long)L2) - KERNBASE;
+ L3[pl3_pi(KERNTEXTOFF)] = xpmap_ptom_masked(addr) | PG_V | PG_RW;
+#else
+ /* no L4 on i386PAE */
+ __USE(L4cpu);
+ __USE(L4);
+
+ /* L3 */
+ L3 = (pd_entry_t *)avail;
+ memset(L3, 0, PAGE_SIZE);
+ avail += PAGE_SIZE;
/*
* Our PAE-style level 2, 5 contiguous pages (4 L2 + 1 shadow).
* +-----------------+----------------+---------+
* Physical layout: | 3 * USERLAND L2 | L2 KERN SHADOW | L2 KERN |
* +-----------------+----------------+---------+
- * However, we enter pdtpte[3] into L2 KERN, and not L2 KERN SHADOW.
- * This way, pde[L2_SLOT_KERN] always points to the shadow.
+ * However, we enter L3[3] into L2 KERN, and not L2 KERN SHADOW.
+ * This way, L2[L2_SLOT_KERN] always points to the shadow.
*/
- pde = (pd_entry_t *)avail;
- memset(pde, 0, PAGE_SIZE * 5);
+ L2 = (pd_entry_t *)avail;
+ memset(L2, 0, PAGE_SIZE * 5);
avail += PAGE_SIZE * 5;
/*
* Link L2 pages in L3, with a special case for L2 KERN. Xen doesn't
* want RW permissions in L3 entries, it'll add them itself.
*/
- addr = ((u_long)pde) - KERNBASE;
+ addr = ((u_long)L2) - KERNBASE;
for (i = 0; i < 3; i++, addr += PAGE_SIZE) {
- pdtpe[i] = xpmap_ptom_masked(addr) | PG_V;
+ L3[i] = xpmap_ptom_masked(addr) | PG_V;
}
addr += PAGE_SIZE;
- pdtpe[3] = xpmap_ptom_masked(addr) | PG_V;
+ L3[3] = xpmap_ptom_masked(addr) | PG_V;
#endif
/* Level 1 */
@@ -729,9 +732,9 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
vaddr_t cur_page = page;
pte = (pd_entry_t *)avail;
+ memset(pte, 0, PAGE_SIZE);
avail += PAGE_SIZE;
- memset(pte, 0, PAGE_SIZE);
while (pl2_pi(page) == pl2_pi(cur_page)) {
if (page >= map_end) {
/* not mapped at all */
@@ -803,8 +806,7 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
}
addr = ((u_long)pte) - KERNBASE;
- pde[pl2_pi(cur_page)] =
- xpmap_ptom_masked(addr) | PG_RW | PG_V;
+ L2[pl2_pi(cur_page)] = xpmap_ptom_masked(addr) | PG_RW | PG_V;
/* Mark readonly */
xen_bt_set_readonly((vaddr_t)pte);
@@ -813,18 +815,18 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
/* Install recursive page tables mapping */
#ifdef __x86_64__
/* Recursive entry in pmap_kernel(). */
- bt_pgd[PDIR_SLOT_PTE] = xpmap_ptom_masked((paddr_t)bt_pgd - KERNBASE)
+ L4[PDIR_SLOT_PTE] = xpmap_ptom_masked((paddr_t)L4 - KERNBASE)
| PG_RO | PG_V | xpmap_pg_nx;
/* Recursive entry in higher-level per-cpu PD. */
- bt_cpu_pgd[PDIR_SLOT_PTE] = xpmap_ptom_masked((paddr_t)bt_cpu_pgd - KERNBASE)
+ L4cpu[PDIR_SLOT_PTE] = xpmap_ptom_masked((paddr_t)L4cpu - KERNBASE)
| PG_RO | PG_V | xpmap_pg_nx;
/* Mark tables RO */
- xen_bt_set_readonly((vaddr_t)pde);
+ xen_bt_set_readonly((vaddr_t)L2);
#else
/* Copy L2 KERN into L2 KERN SHADOW, and reference the latter in cpu0. */
- memcpy(&pde[L2_SLOT_KERN + NPDPG], &pde[L2_SLOT_KERN], PAGE_SIZE);
- cpu_info_primary.ci_kpm_pdir = &pde[L2_SLOT_KERN + NPDPG];
+ memcpy(&L2[L2_SLOT_KERN + NPDPG], &L2[L2_SLOT_KERN], PAGE_SIZE);
+ cpu_info_primary.ci_kpm_pdir = &L2[L2_SLOT_KERN + NPDPG];
cpu_info_primary.ci_kpm_pdirpa =
(vaddr_t)cpu_info_primary.ci_kpm_pdir - KERNBASE;
@@ -834,26 +836,26 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
* have to enter the shadow after switching %cr3, or Xen will refcount
* some PTEs with the wrong type.
*/
- addr = (u_long)pde - KERNBASE;
+ addr = (u_long)L2 - KERNBASE;
for (i = 0; i < 3; i++, addr += PAGE_SIZE) {
- pde[PDIR_SLOT_PTE + i] = xpmap_ptom_masked(addr) | PG_V |
+ L2[PDIR_SLOT_PTE + i] = xpmap_ptom_masked(addr) | PG_V |
xpmap_pg_nx;
}
/* Mark tables RO, and pin L2 KERN SHADOW. */
- addr = (u_long)pde - KERNBASE;
+ addr = (u_long)L2 - KERNBASE;
for (i = 0; i < 5; i++, addr += PAGE_SIZE) {
- xen_bt_set_readonly(((vaddr_t)pde) + PAGE_SIZE * i);
+ xen_bt_set_readonly(((vaddr_t)L2) + PAGE_SIZE * i);
}
if (final) {
- addr = (u_long)pde - KERNBASE + 3 * PAGE_SIZE;
+ addr = (u_long)L2 - KERNBASE + 3 * PAGE_SIZE;
xpq_queue_pin_l2_table(xpmap_ptom_masked(addr));
}
#endif
- xen_bt_set_readonly((vaddr_t)pdtpe);
+ xen_bt_set_readonly((vaddr_t)L3);
#ifdef __x86_64__
- xen_bt_set_readonly(new_pgd);
+ xen_bt_set_readonly((vaddr_t)L4cpu);
#endif
/* Pin the PGD */
@@ -865,9 +867,9 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
/* Save phys. addr of PDP, for libkvm. */
#ifdef __x86_64__
- PDPpaddr = (u_long)bt_pgd - KERNBASE;
+ PDPpaddr = (u_long)L4 - KERNBASE;
#else
- PDPpaddr = (u_long)pde - KERNBASE; /* PDP is the L2 with PAE */
+ PDPpaddr = (u_long)L2 - KERNBASE; /* PDP is the L2 with PAE */
#endif
/* Switch to new tables */
@@ -876,17 +878,17 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
if (final) {
#ifdef __x86_64__
/* Save the address of the real per-cpu L4 page. */
- cpu_info_primary.ci_kpm_pdir = bt_cpu_pgd;
- cpu_info_primary.ci_kpm_pdirpa = ((paddr_t)bt_cpu_pgd - KERNBASE);
+ cpu_info_primary.ci_kpm_pdir = L4cpu;
+ cpu_info_primary.ci_kpm_pdirpa = ((paddr_t)L4cpu - KERNBASE);
#else
/* Save the address of the L3 page */
- cpu_info_primary.ci_pae_l3_pdir = pdtpe;
+ cpu_info_primary.ci_pae_l3_pdir = L3;
cpu_info_primary.ci_pae_l3_pdirpa = (new_pgd - KERNBASE);
/* Now enter the kernel's PTE mappings */
- addr = (u_long)pde - KERNBASE + PAGE_SIZE * 3;
+ addr = (u_long)L2 - KERNBASE + PAGE_SIZE * 3;
xpq_queue_pte_update(
- xpmap_ptom(((vaddr_t)&pde[PDIR_SLOT_PTE + 3]) - KERNBASE),
+ xpmap_ptom(((vaddr_t)&L2[PDIR_SLOT_PTE + 3]) - KERNBASE),
xpmap_ptom_masked(addr) | PG_V);
xpq_flush_queue();
#endif
@@ -901,7 +903,7 @@ xen_bootstrap_tables(vaddr_t old_pgd, va
/* Mark old tables RW */
page = old_pgd;
- addr = xpmap_mtop((paddr_t)pde[pl2_pi(page)] & PG_FRAME);
+ addr = xpmap_mtop((paddr_t)L2[pl2_pi(page)] & PG_FRAME);
pte = (pd_entry_t *)((u_long)addr + KERNBASE);
pte += pl1_pi(page);
while (page < old_pgd + (old_count * PAGE_SIZE) && page < map_end) {
