ia32_syscall.c revision 225474
1/*- 2 * Copyright (C) 1994, David Greenman 3 * Copyright (c) 1990, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the University of Utah, and William Jolitz. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: head/sys/amd64/ia32/ia32_syscall.c 225474 2011-09-11 16:05:09Z kib $"); 40 41/* 42 * 386 Trap and System call handling 43 */ 44 45#include "opt_clock.h" 46#include "opt_compat.h" 47#include "opt_cpu.h" 48#include "opt_isa.h" 49 50#include <sys/param.h> 51#include <sys/bus.h> 52#include <sys/systm.h> 53#include <sys/proc.h> 54#include <sys/pioctl.h> 55#include <sys/kernel.h> 56#include <sys/ktr.h> 57#include <sys/lock.h> 58#include <sys/mutex.h> 59#include <sys/proc.h> 60#include <sys/ptrace.h> 61#include <sys/resourcevar.h> 62#include <sys/signalvar.h> 63#include <sys/syscall.h> 64#include <sys/sysctl.h> 65#include <sys/sysent.h> 66#include <sys/uio.h> 67#include <sys/vmmeter.h> 68#include <security/audit/audit.h> 69 70#include <vm/vm.h> 71#include <vm/vm_param.h> 72#include <vm/pmap.h> 73#include <vm/vm_kern.h> 74#include <vm/vm_map.h> 75#include <vm/vm_page.h> 76#include <vm/vm_extern.h> 77 78#include <machine/cpu.h> 79#include <machine/intr_machdep.h> 80#include <machine/md_var.h> 81 82#include <compat/freebsd32/freebsd32_signal.h> 83#include <compat/freebsd32/freebsd32_util.h> 84#include <compat/ia32/ia32_signal.h> 85#include <machine/psl.h> 86#include <machine/segments.h> 87#include <machine/specialreg.h> 88#include <machine/sysarch.h> 89#include <machine/frame.h> 90#include <machine/md_var.h> 91#include <machine/pcb.h> 92#include <machine/cpufunc.h> 93 94#define IDTVEC(name) __CONCAT(X,name) 95 96extern inthand_t IDTVEC(int0x80_syscall), IDTVEC(rsvd); 97 98void ia32_syscall(struct trapframe *frame); /* Called from asm code */ 99 100void 101ia32_set_syscall_retval(struct thread *td, int error) 102{ 103 104 cpu_set_syscall_retval(td, error); 105} 106 107int 108ia32_fetch_syscall_args(struct thread *td, struct syscall_args *sa) 109{ 110 struct proc *p; 111 struct trapframe *frame; 112 caddr_t params; 113 u_int32_t args[8]; 114 int error, i; 115 116 p = td->td_proc; 117 frame = td->td_frame; 118 119 params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t); 120 sa->code = frame->tf_rax; 121 122 /* 123 * Need to check if this is a 32 bit or 64 bit syscall. 124 */ 125 if (sa->code == SYS_syscall) { 126 /* 127 * Code is first argument, followed by actual args. 128 */ 129 sa->code = fuword32(params); 130 params += sizeof(int); 131 } else if (sa->code == SYS___syscall) { 132 /* 133 * Like syscall, but code is a quad, so as to maintain 134 * quad alignment for the rest of the arguments. 135 * We use a 32-bit fetch in case params is not 136 * aligned. 137 */ 138 sa->code = fuword32(params); 139 params += sizeof(quad_t); 140 } 141 if (p->p_sysent->sv_mask) 142 sa->code &= p->p_sysent->sv_mask; 143 if (sa->code >= p->p_sysent->sv_size) 144 sa->callp = &p->p_sysent->sv_table[0]; 145 else 146 sa->callp = &p->p_sysent->sv_table[sa->code]; 147 sa->narg = sa->callp->sy_narg; 148 149 if (params != NULL && sa->narg != 0) 150 error = copyin(params, (caddr_t)args, 151 (u_int)(sa->narg * sizeof(int))); 152 else 153 error = 0; 154 155 for (i = 0; i < sa->narg; i++) 156 sa->args[i] = args[i]; 157 158 if (error == 0) { 159 td->td_retval[0] = 0; 160 td->td_retval[1] = frame->tf_rdx; 161 } 162 163 return (error); 164} 165 166#include "../../kern/subr_syscall.c" 167 168void 169ia32_syscall(struct trapframe *frame) 170{ 171 struct thread *td; 172 struct syscall_args sa; 173 register_t orig_tf_rflags; 174 int error; 175 ksiginfo_t ksi; 176 177 orig_tf_rflags = frame->tf_rflags; 178 td = curthread; 179 td->td_frame = frame; 180 181 error = syscallenter(td, &sa); 182 183 /* 184 * Traced syscall. 185 */ 186 if (orig_tf_rflags & PSL_T) { 187 frame->tf_rflags &= ~PSL_T; 188 ksiginfo_init_trap(&ksi); 189 ksi.ksi_signo = SIGTRAP; 190 ksi.ksi_code = TRAP_TRACE; 191 ksi.ksi_addr = (void *)frame->tf_rip; 192 trapsignal(td, &ksi); 193 } 194 195 syscallret(td, error, &sa); 196} 197 198static void 199ia32_syscall_enable(void *dummy) 200{ 201 202 setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0); 203} 204 205static void 206ia32_syscall_disable(void *dummy) 207{ 208 209 setidt(IDT_SYSCALL, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0); 210} 211 212SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL); 213SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL); 214 215#ifdef COMPAT_43 216int 217setup_lcall_gate(void) 218{ 219 struct i386_ldt_args uap; 220 struct user_segment_descriptor descs[2]; 221 struct gate_descriptor *ssd; 222 uint32_t lcall_addr; 223 int error; 224 225 bzero(&uap, sizeof(uap)); 226 uap.start = 0; 227 uap.num = 2; 228 229 /* 230 * This is the easiest way to cut the space for system 231 * descriptor in ldt. Manually adjust the descriptor type to 232 * the call gate later. 233 */ 234 bzero(&descs[0], sizeof(descs)); 235 descs[0].sd_type = SDT_SYSNULL; 236 descs[1].sd_type = SDT_SYSNULL; 237 error = amd64_set_ldt(curthread, &uap, descs); 238 if (error != 0) 239 return (error); 240 241 lcall_addr = curproc->p_sysent->sv_psstrings - sz_lcall_tramp; 242 mtx_lock(&dt_lock); 243 ssd = (struct gate_descriptor *)(curproc->p_md.md_ldt->ldt_base); 244 bzero(ssd, sizeof(*ssd)); 245 ssd->gd_looffset = lcall_addr; 246 ssd->gd_hioffset = lcall_addr >> 16; 247 ssd->gd_selector = _ucode32sel; 248 ssd->gd_type = SDT_SYSCGT; 249 ssd->gd_dpl = SEL_UPL; 250 ssd->gd_p = 1; 251 mtx_unlock(&dt_lock); 252 253 return (0); 254} 255#endif 256