1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 #include "thr_uberdata.h" 27 #include <procfs.h> 28 #include <ucontext.h> 29 #include <setjmp.h> 30 31 /* 32 * The stack needs to be 16-byte aligned with a 4-byte bias. See comment in 33 * lib/libc/i386/gen/makectxt.c. 34 * 35 * Note: If you change it, you need to change it in the following files as 36 * well: 37 * 38 * - lib/libc/i386/gen/makectxt.c 39 * - lib/crt/i386/crti.s 40 * - lib/crt/i386/crt1.s 41 */ 42 #undef STACK_ALIGN 43 #define STACK_ALIGN 16 44 45 extern int getlwpstatus(thread_t, lwpstatus_t *); 46 extern int putlwpregs(thread_t, prgregset_t); 47 48 void * 49 setup_top_frame(void *stk, size_t stksize, ulwp_t *ulwp) 50 { 51 uint32_t *stack; 52 struct { 53 uint32_t rpc; 54 uint32_t arg; 55 uint32_t pad; 56 uint32_t fp; 57 uint32_t pc; 58 } frame; 59 60 /* 61 * Top-of-stack must be rounded down to STACK_ALIGN and 62 * there must be a minimum frame. Note: 'frame' is not a true 63 * stack frame (see <sys/frame.h>) but a construction made here to 64 * make it look like _lwp_start called the thread start function 65 * with a 16-byte aligned stack pointer (the address of frame.arg 66 * is the address that muet be aligned on a 16-byte boundary). 67 */ 68 stack = (uint32_t *)(((uintptr_t)stk + stksize) & ~(STACK_ALIGN-1)); 69 70 /* 71 * This will return NULL if the kernel cannot allocate 72 * a page for the top page of the stack. This will cause 73 * thr_create(), pthread_create() or pthread_attr_setstack() 74 * to fail, passing the problem up to the application. 75 */ 76 stack -= 5; /* make the address of frame.arg be 16-byte aligned */ 77 frame.pc = 0; 78 frame.fp = 0; /* initial address for %ebp (see EBP below) */ 79 frame.pad = 0; 80 frame.arg = (uint32_t)ulwp; 81 frame.rpc = (uint32_t)_lwp_start; 82 if (uucopy(&frame, (void *)stack, sizeof (frame)) == 0) 83 return (stack); 84 return (NULL); 85 } 86 87 int 88 setup_context(ucontext_t *ucp, void *(*func)(ulwp_t *), 89 ulwp_t *ulwp, caddr_t stk, size_t stksize) 90 { 91 static int initialized; 92 static greg_t fs, es, ds, cs, ss; 93 94 uint32_t *stack; 95 96 if (!initialized) { 97 ucontext_t uc; 98 99 /* do this once to load the segment registers */ 100 uc.uc_flags = UC_CPU; 101 (void) __getcontext(&uc); 102 fs = uc.uc_mcontext.gregs[FS]; 103 es = uc.uc_mcontext.gregs[ES]; 104 ds = uc.uc_mcontext.gregs[DS]; 105 cs = uc.uc_mcontext.gregs[CS]; 106 ss = uc.uc_mcontext.gregs[SS]; 107 initialized = 1; 108 } 109 /* clear the context and set the segment registers */ 110 (void) memset(ucp, 0, sizeof (*ucp)); 111 ucp->uc_mcontext.gregs[FS] = fs; 112 ucp->uc_mcontext.gregs[ES] = es; 113 ucp->uc_mcontext.gregs[DS] = ds; 114 ucp->uc_mcontext.gregs[CS] = cs; 115 ucp->uc_mcontext.gregs[SS] = ss; 116 117 /* 118 * Yuck. 119 * Use unused kernel pointer field in ucontext 120 * to pass down self pointer and set %gs selector 121 * value so __lwp_create() can setup %gs atomically. 122 * Without this we would need to block all signals 123 * and directly call ___lwp_private() in _thrp_setup 124 * on the other side of __lwp_create(). 125 */ 126 ucp->uc_mcontext.gregs[ESP] = (greg_t)ulwp; 127 ucp->uc_mcontext.gregs[GS] = (greg_t)LWPGS_SEL; 128 129 /* 130 * Setup the top stack frame. 131 * If this fails, pass the problem up to the application. 132 */ 133 if ((stack = setup_top_frame(stk, stksize, ulwp)) == NULL) 134 return (ENOMEM); 135 136 /* fill in registers of interest */ 137 ucp->uc_flags |= UC_CPU; 138 ucp->uc_mcontext.gregs[EIP] = (greg_t)func; 139 ucp->uc_mcontext.gregs[UESP] = (greg_t)stack; 140 ucp->uc_mcontext.gregs[EBP] = (greg_t)(stack + 3); 141 142 return (0); 143 } 144 145 /* 146 * Machine-dependent startup code for a newly-created thread. 147 */ 148 void * 149 _thrp_setup(ulwp_t *self) 150 { 151 self->ul_ustack.ss_sp = (void *)(self->ul_stktop - self->ul_stksiz); 152 self->ul_ustack.ss_size = self->ul_stksiz; 153 self->ul_ustack.ss_flags = 0; 154 (void) setustack(&self->ul_ustack); 155 156 update_sched(self); 157 tls_setup(); 158 159 /* signals have been deferred until now */ 160 sigon(self); 161 162 if (self->ul_cancel_pending == 2 && !self->ul_cancel_disabled) 163 return (NULL); /* cancelled by pthread_create() */ 164 return (self->ul_startpc(self->ul_startarg)); 165 } 166 167 void 168 _fpinherit(ulwp_t *ulwp) 169 { 170 ulwp->ul_fpuenv.ftag = 0xffffffff; 171 } 172 173 void 174 getgregs(ulwp_t *ulwp, gregset_t rs) 175 { 176 lwpstatus_t status; 177 178 if (getlwpstatus(ulwp->ul_lwpid, &status) == 0) { 179 rs[EIP] = status.pr_reg[EIP]; 180 rs[EDI] = status.pr_reg[EDI]; 181 rs[ESI] = status.pr_reg[ESI]; 182 rs[EBP] = status.pr_reg[EBP]; 183 rs[EBX] = status.pr_reg[EBX]; 184 rs[UESP] = status.pr_reg[UESP]; 185 } else { 186 rs[EIP] = 0; 187 rs[EDI] = 0; 188 rs[ESI] = 0; 189 rs[EBP] = 0; 190 rs[EBX] = 0; 191 rs[UESP] = 0; 192 } 193 } 194 195 void 196 setgregs(ulwp_t *ulwp, gregset_t rs) 197 { 198 lwpstatus_t status; 199 200 if (getlwpstatus(ulwp->ul_lwpid, &status) == 0) { 201 status.pr_reg[EIP] = rs[EIP]; 202 status.pr_reg[EDI] = rs[EDI]; 203 status.pr_reg[ESI] = rs[ESI]; 204 status.pr_reg[EBP] = rs[EBP]; 205 status.pr_reg[EBX] = rs[EBX]; 206 status.pr_reg[UESP] = rs[UESP]; 207 (void) putlwpregs(ulwp->ul_lwpid, status.pr_reg); 208 } 209 } 210 211 int 212 __csigsetjmp(greg_t cs, greg_t ss, greg_t gs, 213 greg_t fs, greg_t es, greg_t ds, 214 greg_t edi, greg_t esi, greg_t ebp, greg_t esp, 215 greg_t ebx, greg_t edx, greg_t ecx, greg_t eax, greg_t eip, 216 sigjmp_buf env, int savemask) 217 { 218 ucontext_t *ucp = (ucontext_t *)env; 219 ulwp_t *self = curthread; 220 221 ucp->uc_link = self->ul_siglink; 222 if (self->ul_ustack.ss_flags & SS_ONSTACK) 223 ucp->uc_stack = self->ul_ustack; 224 else { 225 ucp->uc_stack.ss_sp = 226 (void *)(self->ul_stktop - self->ul_stksiz); 227 ucp->uc_stack.ss_size = self->ul_stksiz; 228 ucp->uc_stack.ss_flags = 0; 229 } 230 ucp->uc_flags = UC_STACK | UC_CPU; 231 if (savemask) { 232 ucp->uc_flags |= UC_SIGMASK; 233 enter_critical(self); 234 ucp->uc_sigmask = self->ul_sigmask; 235 exit_critical(self); 236 } 237 ucp->uc_mcontext.gregs[GS] = gs; 238 ucp->uc_mcontext.gregs[FS] = fs; 239 ucp->uc_mcontext.gregs[ES] = es; 240 ucp->uc_mcontext.gregs[DS] = ds; 241 ucp->uc_mcontext.gregs[EDI] = edi; 242 ucp->uc_mcontext.gregs[ESI] = esi; 243 ucp->uc_mcontext.gregs[EBP] = ebp; 244 ucp->uc_mcontext.gregs[ESP] = esp + 4; 245 ucp->uc_mcontext.gregs[EBX] = ebx; 246 ucp->uc_mcontext.gregs[EDX] = edx; 247 ucp->uc_mcontext.gregs[ECX] = ecx; 248 ucp->uc_mcontext.gregs[EAX] = eax; 249 ucp->uc_mcontext.gregs[TRAPNO] = 0; 250 ucp->uc_mcontext.gregs[ERR] = 0; 251 ucp->uc_mcontext.gregs[EIP] = eip; 252 ucp->uc_mcontext.gregs[CS] = cs; 253 ucp->uc_mcontext.gregs[EFL] = 0; 254 ucp->uc_mcontext.gregs[UESP] = esp + 4; 255 ucp->uc_mcontext.gregs[SS] = ss; 256 257 return (0); 258 } 259 260 void 261 smt_pause(void) 262 { 263 SMT_PAUSE(); 264 } 265