NetBSD/sys/arch/powerpc/include/oea/pte.h
chs 939df36e55 add support for non-executable mappings (where the hardware allows this)
and make the stack and heap non-executable by default.  the changes
fall into two basic catagories:

 - pmap and trap-handler changes.  these are all MD:
   = alpha: we already track per-page execute permission with the (software)
	PG_EXEC bit, so just have the trap handler pay attention to it.
   = i386: use a new GDT segment for %cs for processes that have no
	executable mappings above a certain threshold (currently the
	bottom of the stack).  track per-page execute permission with
	the last unused PTE bit.
   = powerpc/ibm4xx: just use the hardware exec bit.
   = powerpc/oea: we already track per-page exec bits, but the hardware only
	implements non-exec mappings at the segment level.  so track the
	number of executable mappings in each segment and turn on the no-exec
	segment bit iff the count is 0.  adjust the trap handler to deal.
   = sparc (sun4m): fix our use of the hardware protection bits.
	fix the trap handler to recognize text faults.
   = sparc64: split the existing unified TSB into data and instruction TSBs,
	and only load TTEs into the appropriate TSB(s) for the permissions.
	fix the trap handler to check for execute permission.
   = not yet implemented: amd64, hppa, sh5

 - changes in all the emulations that put a signal trampoline on the stack.
   instead, we now put the trampoline into a uvm_aobj and map that into
   the process separately.

originally from openbsd, adapted for netbsd by me.
2003-08-24 17:52:28 +00:00

103 lines
3.5 KiB
C

/* $NetBSD: pte.h,v 1.3 2003/08/24 17:52:34 chs Exp $ */
/*-
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _POWERPC_OEA_PTE_H_
#define _POWERPC_OEA_PTE_H_
#include <sys/queue.h>
/*
* Page Table Entries
*/
#ifndef _LOCORE
struct pte {
register_t pte_hi;
register_t pte_lo;
};
struct pteg {
struct pte pt[8];
};
#endif /* _LOCORE */
/* High word: */
#define PTE_VALID 0x80000000
#define PTE_VSID 0x7fffff80
#define PTE_VSID_SHFT 7
#define PTE_VSID_LEN 24
#define PTE_HID 0x00000040
#define PTE_API 0x0000003f
#define PTE_API_SHFT 0
/* Low word: */
#define PTE_RPGN 0xfffff000
#define PTE_RPGN_SHFT 12
#define PTE_REF 0x00000100
#define PTE_CHG 0x00000080
#define PTE_W 0x00000040 /* 1 = write-through, 0 = write-back */
#define PTE_I 0x00000020 /* cache inhibit */
#define PTE_M 0x00000010 /* memory coherency enable */
#define PTE_G 0x00000008 /* guarded region (not on 601) */
#define PTE_WIMG (PTE_W|PTE_I|PTE_M|PTE_G)
#define PTE_IG (PTE_I|PTE_G)
#define PTE_PP 0x00000003
#define PTE_SO 0x00000000 /* Super. Only (U: XX, S: RW) */
#define PTE_SW 0x00000001 /* Super. Write-Only (U: RO, S: RW) */
#define PTE_BW 0x00000002 /* Supervisor (U: RW, S: RW) */
#define PTE_BR 0x00000003 /* Both Read Only (U: RO, S: RO) */
#define PTE_RW PTE_BW
#define PTE_RO PTE_BR
#define PTE_EXEC 0x00000200 /* pseudo bit; page is exec */
/*
* Extract bits from address
*/
#define ADDR_SR_SHFT 28
#define ADDR_PIDX 0x0ffff000
#define ADDR_PIDX_SHFT 12
#define ADDR_API_SHFT 22
#define ADDR_POFF 0x00000fff
#define ADDR_SEG_WIDTH 4
/*
* Segment registers
*/
#define SR_KEY_LEN 4 /* key bit width */
#define SR_TYPE 0x80000000 /* T=0 selects memory format */
#define SR_SUKEY 0x40000000 /* Supervisor protection key */
#define SR_PRKEY 0x20000000 /* User protection key */
#define SR_NOEXEC 0x10000000 /* No-execute protection bit */
#define SR_VSID 0x00ffffff /* Virtual segment ID */
#endif /* _POWERPC_OEA_PTE_H_ */