[src/trunk]: src/sys/arch/i386 Move KERNBASE to 0xc0000000, giving the kernel...

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

details:   https://anonhg.NetBSD.org/src/rev/d17d622c8dfb
branches:  trunk
changeset: 481982:d17d622c8dfb
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Fri Feb 11 07:00:11 2000 +0000

description:
Move KERNBASE to 0xc0000000, giving the kernel a more-or-less full 1G
of virtual address space, leaving userland with 3G, and update comments
to match the new reality.

We knew we were going to have to bite this bullet eventually, and there
are a couple of outstanding PRs related to this issue (9389 and 9313).
Complete solution to those PRs is going to involve some sort of run-time
decision on how large kmem_map should be, as well as changing some data
structure allocation strategies in UVM.  However, this change will at
least allow the PR submitter to simply throw resources at the problem.

diffstat:

 sys/arch/i386/conf/Makefile.i386 |   4 +-
 sys/arch/i386/include/param.h    |   6 ++--
 sys/arch/i386/include/pmap.h     |  42 ++++++++++++++++++++--------------------
 sys/arch/i386/include/vmparam.h  |  16 +++++++-------
 4 files changed, 34 insertions(+), 34 deletions(-)

diffs (169 lines):

diff -r ed6c945b73e5 -r d17d622c8dfb sys/arch/i386/conf/Makefile.i386
--- a/sys/arch/i386/conf/Makefile.i386  Fri Feb 11 06:11:03 2000 +0000
+++ b/sys/arch/i386/conf/Makefile.i386  Fri Feb 11 07:00:11 2000 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: Makefile.i386,v 1.103 2000/02/01 05:25:32 tsutsui Exp $
+#      $NetBSD: Makefile.i386,v 1.104 2000/02/11 07:00:11 thorpej Exp $
 
 # Makefile for NetBSD
 #
@@ -54,7 +54,7 @@
 .endif
 CFLAGS=                ${DEBUG} ${COPTS} ${CWARNFLAGS}
 AFLAGS=                -x assembler-with-cpp -traditional-cpp -D_LOCORE
-LINKFLAGS=     -Ttext F0100000 -e start
+LINKFLAGS=     -Ttext c0100000 -e start
 .if (${OBJECT_FMT} == "ELF")
 #LINKFLAGS+=   -N
 .else
diff -r ed6c945b73e5 -r d17d622c8dfb sys/arch/i386/include/param.h
--- a/sys/arch/i386/include/param.h     Fri Feb 11 06:11:03 2000 +0000
+++ b/sys/arch/i386/include/param.h     Fri Feb 11 07:00:11 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: param.h,v 1.38 1999/12/04 21:20:34 ragge Exp $ */
+/*     $NetBSD: param.h,v 1.39 2000/02/11 07:00:13 thorpej Exp $       */
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -76,8 +76,8 @@
 #define        PGOFSET         (NBPG-1)        /* byte offset into page */
 #define        NPTEPG          (NBPG/(sizeof (pt_entry_t)))
 
-#define        KERNBASE        0xf0000000      /* start of kernel virtual space */
-#define        KERNTEXTOFF     0xf0100000      /* start of kernel text */
+#define        KERNBASE        0xc0000000      /* start of kernel virtual space */
+#define        KERNTEXTOFF     0xc0100000      /* start of kernel text */
 #define        BTOPKERNBASE    ((u_long)KERNBASE >> PGSHIFT)
 
 #define        DEV_BSHIFT      9               /* log2(DEV_BSIZE) */
diff -r ed6c945b73e5 -r d17d622c8dfb sys/arch/i386/include/pmap.h
--- a/sys/arch/i386/include/pmap.h      Fri Feb 11 06:11:03 2000 +0000
+++ b/sys/arch/i386/include/pmap.h      Fri Feb 11 07:00:11 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: pmap.h,v 1.42 1999/07/28 01:07:59 thorpej Exp $        */
+/*     $NetBSD: pmap.h,v 1.43 2000/02/11 07:00:13 thorpej Exp $        */
 
 /*
  *
@@ -57,17 +57,17 @@
  * are described by PDEs in the PDP.  the PDEs are defined as follows:
  *
  * (ranges are inclusive -> exclusive, just like vm_map_entry start/end)
- * (the following assumes that KERNBASE is 0xf0000000)
+ * (the following assumes that KERNBASE is 0xc0000000)
  *
  * PDE#s       VA range                usage
- * 0->959      0x0 -> 0xefc00000       user address space, note that the
- *                                     max user address is 0xefbfe000
+ * 0->767      0x0 -> 0xbfc00000       user address space, note that the
+ *                                     max user address is 0xbfbfe000
  *                                     the final two pages in the last 4MB
  *                                     used to be reserved for the UAREA
  *                                     but now are no longer used
- * 959         0xefc00000->            recursive mapping of PDP (used for
- *                     0xf0000000      linear mapping of PTPs)
- * 960->1023   0xf0000000->            kernel address space (constant
+ * 768         0xbfc00000->            recursive mapping of PDP (used for
+ *                     0xc0000000      linear mapping of PTPs)
+ * 768->1023   0xc0000000->            kernel address space (constant
  *                     0xffc00000      across all pmap's/processes)
  * 1023                0xffc00000->            "alternate" recursive PDP mapping
  *                     <end>           (for other pmaps)
@@ -80,18 +80,18 @@
  * 4MB range is the PTE that maps VA 0xffffe000 (the last page in a 4GB
  * address).
  *
- * all pmap's PD's must have the same values in slots 960->1023 so that
+ * all pmap's PD's must have the same values in slots 768->1023 so that
  * the kernel is always mapped in every process.  these values are loaded
  * into the PD at pmap creation time.
  *
  * at any one time only one pmap can be active on a processor.  this is
  * the pmap whose PDP is pointed to by processor register %cr3.  this pmap
  * will have all its PTEs mapped into memory at the recursive mapping
- * point (slot #959 as show above).  when the pmap code wants to find the
+ * point (slot #767 as show above).  when the pmap code wants to find the
  * PTE for a virtual address, all it has to do is the following:
  *
- * address of PTE = (959 * 4MB) + (VA / NBPG) * sizeof(pt_entry_t)
- *                = 0xefc00000 + (VA / 4096) * 4
+ * address of PTE = (767 * 4MB) + (VA / NBPG) * sizeof(pt_entry_t)
+ *                = 0xbfc00000 + (VA / 4096) * 4
  *
  * what happens if the pmap layer is asked to perform an operation
  * on a pmap that is not the one which is currently active?  in that
@@ -107,25 +107,25 @@
  *   |   0| -> PTP#0 that maps VA 0x0 -> 0x400000
  *   |    |
  *   |    |
- *   | 959| -> points back to PDP (%cr3) mapping VA 0xefc00000 -> 0xf0000000
- *   | 960| -> first kernel PTP (maps 0xf0000000 -> 0xf0400000)
+ *   | 767| -> points back to PDP (%cr3) mapping VA 0xbfc00000 -> 0xc0000000
+ *   | 768| -> first kernel PTP (maps 0xc0000000 -> 0xf0400000)
  *   |    |
  *   |1023| -> points to alternate pmap's PDP (maps 0xffc00000 -> end)
  *   +----+
  *
- * note that the PDE#959 VA (0xefc00000) is defined as "PTE_BASE"
+ * note that the PDE#767 VA (0xbfc00000) is defined as "PTE_BASE"
  * note that the PDE#1023 VA (0xffc00000) is defined as "APTE_BASE"
  *
- * starting at VA 0xefc00000 the current active PDP (%cr3) acts as a
+ * starting at VA 0xbfc00000 the current active PDP (%cr3) acts as a
  * PTP:
  *
- * PTP#959 == PDP(%cr3) => maps VA 0xefc00000 -> 0xf0000000
+ * PTP#767 == PDP(%cr3) => maps VA 0xbfc00000 -> 0xc0000000
  *   +----+
- *   |   0| -> maps the contents of PTP#0 at VA 0xefc00000->0xefc01000
+ *   |   0| -> maps the contents of PTP#0 at VA 0xbfc00000->0xbfc01000
  *   |    |
  *   |    |
- *   | 959| -> maps contents of PTP#959 (the PDP) at VA 0xeffbf000
- *   | 960| -> maps contents of first kernel PTP
+ *   | 767| -> maps contents of PTP#767 (the PDP) at VA 0xbffbf000
+ *   | 768| -> maps contents of first kernel PTP
  *   |    |
  *   |1023|
  *   +----+
@@ -148,8 +148,8 @@
  * the following defines identify the slots used as described above.
  */
 
-#define PDSLOT_PTE     ((KERNBASE/NBPD)-1) /* 959: for recursive PDP map */
-#define PDSLOT_KERN    (KERNBASE/NBPD)     /* 960: start of kernel space */
+#define PDSLOT_PTE     ((KERNBASE/NBPD)-1) /* 767: for recursive PDP map */
+#define PDSLOT_KERN    (KERNBASE/NBPD)     /* 768: start of kernel space */
 #define PDSLOT_APTE    ((unsigned)1023) /* 1023: alternative recursive slot */
 
 /*
diff -r ed6c945b73e5 -r d17d622c8dfb sys/arch/i386/include/vmparam.h
--- a/sys/arch/i386/include/vmparam.h   Fri Feb 11 06:11:03 2000 +0000
+++ b/sys/arch/i386/include/vmparam.h   Fri Feb 11 07:00:11 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vmparam.h,v 1.34 2000/01/26 09:44:11 tsutsui Exp $     */
+/*     $NetBSD: vmparam.h,v 1.35 2000/02/11 07:00:13 thorpej Exp $     */
 
 /*-
  * Copyright (c) 1990 The Regents of the University of California.
@@ -105,13 +105,13 @@
 
 /* user/kernel map constants */
 #define VM_MIN_ADDRESS         ((vaddr_t)0)
-/* PTDPTDI<<PDSHIFT - UPAGES*NBPG */
-#define VM_MAXUSER_ADDRESS     ((vaddr_t)0xefbfe000)
-/* PTDPTDI<<PDSHIFT + PTDPTDI<<PGSHIFT */
-#define VM_MAX_ADDRESS         ((vaddr_t)0xeffbf000)
-/* KPTDI<<PDSHIFT */
-#define VM_MIN_KERNEL_ADDRESS  ((vaddr_t)0xf0000000)
-/* APTDPTDI<<PDSHIFT */
+/* (PDSLOT_PTE << PDSHIFT) - UPAGES*NBPG */
+#define VM_MAXUSER_ADDRESS     ((vaddr_t)0xbfbfe000)
+/* (PDSLOT_PTE << PDSHIFT) + (PDSLOT_PTE << PGSHIFT) */
+#define VM_MAX_ADDRESS         ((vaddr_t)0xbfeff000)
+/* PDSLOT_KERN << PDSHIFT */
+#define VM_MIN_KERNEL_ADDRESS  ((vaddr_t)0xc0000000)
+/* PDSLOT_APTE << PDSHIFT */
 #define VM_MAX_KERNEL_ADDRESS  ((vaddr_t)0xffc00000)
 
 /* XXX max. amount of KVM to be used by buffers. */