1 /* $NetBSD: pcb.h,v 1.15 2007/03/04 06:00:49 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * All advertising materials mentioning features or use of this software 12 * must display the following acknowledgement: 13 * This product includes software developed by the University of 14 * California, Lawrence Berkeley Laboratory. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)pcb.h 8.1 (Berkeley) 6/11/93 41 */ 42 43 /* 44 * Copyright (c) 1996-2002 Eduardo Horvath. All rights reserved. 45 * 46 * Redistribution and use in source and binary forms, with or without 47 * modification, are permitted provided that the following conditions 48 * are met: 49 * 1. Redistributions of source code must retain the above copyright 50 * notice, this list of conditions and the following disclaimer. 51 * 2. Redistributions in binary form must reproduce the above copyright 52 * notice, this list of conditions and the following disclaimer in the 53 * documentation and/or other materials provided with the distribution. 54 * 3. Neither the name of the author nor the names of its contributors 55 * may be used to endorse or promote products derived from this software 56 * without specific prior written permission. 57 * 58 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 61 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 68 * SUCH DAMAGE. 69 * 70 * @(#)pcb.h 8.1 (Berkeley) 6/11/93 71 */ 72 73 #include <machine/reg.h> 74 75 #ifdef notyet 76 #define PCB_MAXWIN 32 /* architectural limit */ 77 #else 78 #define PCB_MAXWIN 8 /* worried about u area sizes ... */ 79 #endif 80 81 /* 82 * SPARC Process Control Block. 83 * 84 * pcb_uw is positive if there are any user windows that are 85 * are currently in the CPU windows rather than on the user 86 * stack. Whenever we are running in the kernel with traps 87 * enabled, we decrement pcb_uw for each ``push'' of a CPU 88 * register window into the stack, and we increment it for 89 * each ``pull'' from the stack into the CPU. (If traps are 90 * disabled, or if we are in user mode, pcb_uw is junk.) 91 * 92 * To ease computing pcb_uw on traps from user mode, we keep track 93 * of the log base 2 of the single bit that is set in %wim. 94 * 95 * If an overflow occurs while the associated user stack pages 96 * are invalid (paged out), we have to store the registers 97 * in a page that is locked in core while the process runs, 98 * i.e., right here in the pcb. We also need the stack pointer 99 * for the last such window (but only the last, as the others 100 * are in each window) and the count of windows saved. We 101 * cheat by having a whole window structure for that one %sp. 102 * Thus, to save window pcb_rw[i] to memory, we write it at 103 * pcb_rw[i + 1].rw_in[6]. 104 * 105 * pcb_nsaved has three `kinds' of values. If 0, it means no 106 * registers are in the PCB (though if pcb_uw is positive, 107 * there may be the next time you look). If positive, it means 108 * there are no user registers in the CPU, but there are some 109 * saved in pcb_rw[]. As a special case, traps that needed 110 * assistance to pull user registers from the stack also store 111 * the registers in pcb_rw[], and set pcb_nsaved to -1. This 112 * special state is normally short-term: it can only last until the 113 * trap returns, and it can never persist across entry to user code. 114 */ 115 /* 116 * v9 addendum: 117 * 118 * Window handling between v8 and v9 has changed somewhat. There 119 * is no %wim. Instead, we have a %cwp, %cansave, %canrestore, 120 * %cleanwin, and %otherwin. By definition: 121 * 122 * %cansave + %canrestore + %otherwin = NWINDOWS - 2 123 * 124 * In addition, %cleanwin >= %canrestore since restorable windows 125 * are considered clean. This means that by storing %canrestore 126 * and %otherwin, we should be able to compute the values of all 127 * the other registers. 128 * 129 * The only other register we need to save is %cwp because it cannot 130 * be trivially computed from the other registers. The %cwp is 131 * stored in the %tstate register, but if the machine was in a register 132 * window spill/fill handler, the value of that %cwp may be off by 133 * as much as 2 register windows. We will also store %cwp. [We will 134 * try to steal pcb_uw or pcb_nsaved for this purpose eventually.] 135 * 136 * To calculate what registers are in the pcb, start with pcb_cwp 137 * and proceed to (pcb_cwp - pcb_canrestore) % NWINDOWS. These should 138 * be saved to their appropriate register windows. The client routine 139 * (trap handler) is responsible for saving pcb_cwp + 1 [%o1-%o7] in 140 * the trap frame or on the stack. 141 * 142 * 143 * Even more addendum: 144 * 145 * With the new system for keeping track of register windows we don't 146 * care about anything other than pcb_uw which keeps track of how many 147 * full windows we have. As soon as a flush traps, we dump all user 148 * windows to the pcb, handle the fault, then restore all user windows. 149 * 150 * XXX we are using pcb_nsaved as the counter. pcb_uw is still a mask. 151 * change this as soon as the new scheme is debugged. 152 */ 153 struct pcb { 154 uint64_t pcb_sp; /* sp (%o6) when switch() was called */ 155 uint64_t pcb_pc; /* pc (%o7) when switch() was called */ 156 void * pcb_onfault; /* for copyin/out */ 157 short pcb_pstate; /* %pstate when switch() was called -- may be useful if we support multiple memory models */ 158 char pcb_nsaved; /* number of windows saved in pcb */ 159 160 /* The rest is probably not needed except for pcb_rw */ 161 char pcb_cwp; /* %cwp when switch() was called */ 162 char pcb_pil; /* %pil when switch() was called -- prolly not needed */ 163 164 const char *lastcall; /* DEBUG -- name of last system call */ 165 /* the following MUST be aligned on a 64-bit boundary */ 166 struct rwindow64 pcb_rw[PCB_MAXWIN]; /* saved windows */ 167 }; 168 169 /* 170 * The pcb is augmented with machine-dependent additional data for 171 * core dumps. Note that the trapframe here is a copy of the one 172 * from the top of the kernel stack (included here so that the kernel 173 * stack itself need not be dumped). 174 */ 175 struct md_coredump32 { 176 struct trapframe32 md_tf; 177 struct fpstate32 md_fpstate; 178 }; 179 180 struct md_coredump { 181 struct trapframe64 md_tf; 182 struct fpstate64 md_fpstate; 183 }; 184 185 #ifndef _KERNEL 186 /* Let gdb compile. We need fancier macros to make these make sense. */ 187 #define pcb_psr pcb_pstate 188 #define pcb_wim pcb_cwp 189 #endif /* _KERNEL */ 190