NetBSD/sys/arch/sparc/include/pcb.h

124 lines
5.1 KiB
C

/* $NetBSD: pcb.h,v 1.4 1995/03/28 18:19:56 jtc Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
*
* 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 the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS OR CONTRIBUTORS 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.
*
* @(#)pcb.h 8.1 (Berkeley) 6/11/93
*/
#include <machine/reg.h>
#ifdef notyet
#define PCB_MAXWIN 32 /* architectural limit */
#else
#define PCB_MAXWIN 8 /* worried about u area sizes ... */
#endif
/*
* SPARC Process Control Block.
*
* pcb_uw is positive if there are any user windows that are
* are currently in the CPU windows rather than on the user
* stack. Whenever we are running in the kernel with traps
* enabled, we decrement pcb_uw for each ``push'' of a CPU
* register window into the stack, and we increment it for
* each ``pull'' from the stack into the CPU. (If traps are
* disabled, or if we are in user mode, pcb_uw is junk.)
*
* To ease computing pcb_uw on traps from user mode, we keep track
* of the log base 2 of the single bit that is set in %wim.
*
* If an overflow occurs while the associated user stack pages
* are invalid (paged out), we have to store the registers
* in a page that is locked in core while the process runs,
* i.e., right here in the pcb. We also need the stack pointer
* for the last such window (but only the last, as the others
* are in each window) and the count of windows saved. We
* cheat by having a whole window structure for that one %sp.
* Thus, to save window pcb_rw[i] to memory, we write it at
* pcb_rw[i + 1].rw_in[6].
*
* pcb_nsaved has three `kinds' of values. If 0, it means no
* registers are in the PCB (though if pcb_uw is positive,
* there may be the next time you look). If positive, it means
* there are no user registers in the CPU, but there are some
* saved in pcb_rw[]. As a special case, traps that needed
* assistance to pull user registers from the stack also store
* the registers in pcb_rw[], and set pcb_nsaved to -1. This
* special state is normally short-term: it can only last until the
* trap returns, and it can never persist across entry to user code.
*/
struct pcb {
int pcb_sp; /* sp (%o6) when switch() was called */
int pcb_pc; /* pc (%o7) when switch() was called */
int pcb_psr; /* %psr when switch() was called */
caddr_t pcb_onfault; /* for copyin/out */
int pcb_uw; /* user windows inside CPU */
int pcb_wim; /* log2(%wim) */
int pcb_nsaved; /* number of windows saved in pcb */
#ifdef notdef
int pcb_winof; /* number of window overflow traps */
int pcb_winuf; /* number of window underflow traps */
#endif
int pcb_pad; /* pad to doubleword boundary */
/* the following MUST be aligned on a doubleword boundary */
struct rwindow pcb_rw[PCB_MAXWIN]; /* saved windows */
};
/*
* The pcb is augmented with machine-dependent additional data for
* core dumps. Note that the trapframe here is a copy of the one
* from the top of the kernel stack (included here so that the kernel
* stack itself need not be dumped).
*/
struct md_coredump {
struct trapframe md_tf;
struct fpstate md_fpstate;
};
#ifdef _KERNEL
extern struct pcb *cpcb;
#endif /* _KERNEL */