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 */
92 ia32_syscall(struct trapframe *frame)
97 struct thread *td = curthread;
98 struct proc *p = td->td_proc;
99 register_t orig_tf_rflags;
107 PCPU_INC(cnt.v_syscall);
109 td->td_frame = frame;
110 if (td->td_ucred != p->p_ucred)
111 cred_update_thread(td);
112 params = (caddr_t)frame->tf_rsp + sizeof(u_int32_t);
113 code = frame->tf_rax;
114 orig_tf_rflags = frame->tf_rflags;
116 if (p->p_sysent->sv_prepsyscall) {
118 * The prep code is MP aware.
120 (*p->p_sysent->sv_prepsyscall)(frame, args, &code, ¶ms);
123 * Need to check if this is a 32 bit or 64 bit syscall.
124 * fuword is MP aware.
126 if (code == SYS_syscall) {
128 * Code is first argument, followed by actual args.
130 code = fuword32(params);
131 params += sizeof(int);
132 } else if (code == SYS___syscall) {
134 * Like syscall, but code is a quad, so as to maintain
135 * quad alignment for the rest of the arguments.
136 * We use a 32-bit fetch in case params is not
139 code = fuword32(params);
140 params += sizeof(quad_t);
144 if (p->p_sysent->sv_mask)
145 code &= p->p_sysent->sv_mask;
147 if (code >= p->p_sysent->sv_size)
148 callp = &p->p_sysent->sv_table[0];
150 callp = &p->p_sysent->sv_table[code];
152 narg = callp->sy_narg;
155 * copyin and the ktrsyscall()/ktrsysret() code is MP-aware
157 if (params != NULL && narg != 0)
158 error = copyin(params, (caddr_t)args,
159 (u_int)(narg * sizeof(int)));
163 for (i = 0; i < narg; i++)
167 if (KTRPOINT(td, KTR_SYSCALL))
168 ktrsyscall(code, narg, args64);
170 CTR4(KTR_SYSC, "syscall enter thread %p pid %d proc %s code %d", td,
171 td->td_proc->p_pid, td->td_proc->p_comm, code);
174 td->td_retval[0] = 0;
175 td->td_retval[1] = frame->tf_rdx;
177 STOPEVENT(p, S_SCE, narg);
179 PTRACESTOP_SC(p, td, S_PT_SCE);
181 AUDIT_SYSCALL_ENTER(code, td);
182 error = (*callp->sy_call)(td, args64);
183 AUDIT_SYSCALL_EXIT(error, td);
188 frame->tf_rax = td->td_retval[0];
189 frame->tf_rdx = td->td_retval[1];
190 frame->tf_rflags &= ~PSL_C;
195 * Reconstruct pc, assuming lcall $X,y is 7 bytes,
196 * int 0x80 is 2 bytes. We saved this in tf_err.
198 frame->tf_rip -= frame->tf_err;
205 if (p->p_sysent->sv_errsize) {
206 if (error >= p->p_sysent->sv_errsize)
207 error = -1; /* XXX */
209 error = p->p_sysent->sv_errtbl[error];
211 frame->tf_rax = error;
212 frame->tf_rflags |= PSL_C;
219 if (orig_tf_rflags & PSL_T) {
220 frame->tf_rflags &= ~PSL_T;
221 ksiginfo_init_trap(&ksi);
222 ksi.ksi_signo = SIGTRAP;
223 ksi.ksi_code = TRAP_TRACE;
224 ksi.ksi_addr = (void *)frame->tf_rip;
225 trapsignal(td, &ksi);
229 * Check for misbehavior.
231 WITNESS_WARN(WARN_PANIC, NULL, "System call %s returning",
232 (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???");
233 KASSERT(td->td_critnest == 0,
234 ("System call %s returning in a critical section",
235 (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???"));
236 KASSERT(td->td_locks == 0,
237 ("System call %s returning with %d locks held",
238 (code >= 0 && code < SYS_MAXSYSCALL) ? freebsd32_syscallnames[code] : "???",
242 * Handle reschedule and other end-of-syscall issues
246 CTR4(KTR_SYSC, "syscall exit thread %p pid %d proc %s code %d", td,
247 td->td_proc->p_pid, td->td_proc->p_comm, code);
249 if (KTRPOINT(td, KTR_SYSRET))
250 ktrsysret(code, error, td->td_retval[0]);
254 * This works because errno is findable through the
255 * register set. If we ever support an emulation where this
256 * is not the case, this code will need to be revisited.
258 STOPEVENT(p, S_SCX, code);
260 PTRACESTOP_SC(p, td, S_PT_SCX);
265 ia32_syscall_enable(void *dummy)
268 setidt(IDT_SYSCALL, &IDTVEC(int0x80_syscall), SDT_SYSIGT, SEL_UPL, 0);
272 ia32_syscall_disable(void *dummy)
275 setidt(IDT_SYSCALL, &IDTVEC(rsvd), SDT_SYSIGT, SEL_KPL, 0);
278 SYSINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_enable, NULL);
279 SYSUNINIT(ia32_syscall, SI_SUB_EXEC, SI_ORDER_ANY, ia32_syscall_disable, NULL);