2 * Copyright (C) 1994, David Greenman
3 * Copyright (c) 1990, 1993
4 * The Regents of the University of California. All rights reserved.
6 * This code is derived from software contributed to Berkeley by
7 * the University of Utah, and William Jolitz.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
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.
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
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
42 * 386 Trap and System call handling
45 #include "opt_clock.h"
48 #include "opt_ktrace.h"
50 #include <sys/param.h>
52 #include <sys/systm.h>
54 #include <sys/pioctl.h>
55 #include <sys/kernel.h>
58 #include <sys/mutex.h>
59 #include <sys/ptrace.h>
60 #include <sys/resourcevar.h>
61 #include <sys/signalvar.h>
62 #include <sys/syscall.h>
63 #include <sys/sysctl.h>
64 #include <sys/sysent.h>
66 #include <sys/vmmeter.h>
68 #include <sys/ktrace.h>
70 #include <security/audit/audit.h>
73 #include <vm/vm_param.h>
75 #include <vm/vm_kern.h>
76 #include <vm/vm_map.h>
77 #include <vm/vm_page.h>
78 #include <vm/vm_extern.h>
80 #include <machine/cpu.h>
81 #include <machine/intr_machdep.h>
82 #include <machine/md_var.h>
84 #define IDTVEC(name) __CONCAT(X,name)
86 extern inthand_t IDTVEC(int0x80_syscall), IDTVEC(rsvd);
87 extern const char *freebsd32_syscallnames[];
89 void ia32_syscall(struct trapframe *frame); /* Called from asm code */
91 struct ia32_syscall_args {
100 fetch_ia32_syscall_args(struct thread *td, struct ia32_syscall_args *sa)
103 struct trapframe *frame;
108 frame = td->td_frame;
110 sa->params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t);
111 sa->code = frame->tf_rax;
113 if (p->p_sysent->sv_prepsyscall) {
115 * The prep code is MP aware.
117 (*p->p_sysent->sv_prepsyscall)(frame, args, &sa->code,
121 * Need to check if this is a 32 bit or 64 bit syscall.
122 * fuword is MP aware.
124 if (sa->code == SYS_syscall) {
126 * Code is first argument, followed by actual args.
128 sa->code = fuword32(sa->params);
129 sa->params += sizeof(int);
130 } else if (sa->code == SYS___syscall) {
132 * Like syscall, but code is a quad, so as to maintain
133 * quad alignment for the rest of the arguments.
134 * We use a 32-bit fetch in case params is not
137 sa->code = fuword32(sa->params);
138 sa->params += sizeof(quad_t);
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];
146 sa->callp = &p->p_sysent->sv_table[sa->code];
147 sa->narg = sa->callp->sy_narg;
149 if (sa->params != NULL && sa->narg != 0)
150 error = copyin(sa->params, (caddr_t)args,
151 (u_int)(sa->narg * sizeof(int)));
155 for (i = 0; i < sa->narg; i++)
156 sa->args64[i] = args[i];
159 if (KTRPOINT(td, KTR_SYSCALL))
160 ktrsyscall(sa->code, sa->narg, sa->args64);
167 ia32_syscall(struct trapframe *frame)
171 struct ia32_syscall_args sa;
172 register_t orig_tf_rflags;
176 PCPU_INC(cnt.v_syscall);
182 td->td_frame = frame;
183 if (td->td_ucred != p->p_ucred)
184 cred_update_thread(td);
185 orig_tf_rflags = frame->tf_rflags;
186 if (p->p_flag & P_TRACED) {
188 td->td_dbgflags &= ~TDB_USERWR;
191 error = fetch_ia32_syscall_args(td, &sa);
193 CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td,
194 td->td_proc->p_pid, td->td_name, sa.code);
197 td->td_retval[0] = 0;
198 td->td_retval[1] = frame->tf_rdx;
200 STOPEVENT(p, S_SCE, sa.narg);
201 PTRACESTOP_SC(p, td, S_PT_SCE);
202 if (td->td_dbgflags & TDB_USERWR) {
204 * Reread syscall number and arguments if
205 * debugger modified registers or memory.
207 error = fetch_ia32_syscall_args(td, &sa);
210 td->td_retval[1] = frame->tf_rdx;
213 AUDIT_SYSCALL_ENTER(sa.code, td);
214 error = (*sa.callp->sy_call)(td, sa.args64);
215 AUDIT_SYSCALL_EXIT(error, td);
217 /* Save the latest error return value. */
218 td->td_errno = error;
221 cpu_set_syscall_retval(td, error);
226 if (orig_tf_rflags & PSL_T) {
227 frame->tf_rflags &= ~PSL_T;
228 ksiginfo_init_trap(&ksi);
229 ksi.ksi_signo = SIGTRAP;
230 ksi.ksi_code = TRAP_TRACE;
231 ksi.ksi_addr = (void *)frame->tf_rip;
232 trapsignal(td, &ksi);
236 * Check for misbehavior.
238 WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
239 (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ?
240 freebsd32_syscallnames[sa.code] : "???");
241 KASSERT(td->td_critnest == 0,
242 ("System call %s returning in a critical section",
243 (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ?
244 freebsd32_syscallnames[sa.code] : "???"));
245 KASSERT(td->td_locks == 0,
246 ("System call %s returning with %d locks held",
247 (sa.code >= 0 && sa.code < SYS_MAXSYSCALL) ?
248 freebsd32_syscallnames[sa.code] : "???", td->td_locks));
251 * Handle reschedule and other end-of-syscall issues
255 CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td,
256 td->td_proc->p_pid, td->td_proc->p_comm, sa.code);
258 if (KTRPOINT(td, KTR_SYSRET))
259 ktrsysret(sa.code, error, td->td_retval[0]);
263 * This works because errno is findable through the
264 * register set. If we ever support an emulation where this
265 * is not the case, this code will need to be revisited.
267 STOPEVENT(p, S_SCX, sa.code);
269 PTRACESTOP_SC(p, td, S_PT_SCX);
274 ia32_syscall_enable(void *dummy)
277 setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0);
281 ia32_syscall_disable(void *dummy)
284 setidt(IDT_SYSCALL, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
287 SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL);
288 SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL);