static void
systrace_init(struct sysent *actual, systrace_sysent_t **interposed)
{
systrace_sysent_t *sysent = *interposed;
int i;
if (sysent == NULL) {
*interposed = sysent = kmem_zalloc(sizeof (systrace_sysent_t) *
NSYSCALL, KM_SLEEP);
}
for (i = 0; i < NSYSCALL; i++) {
struct sysent *a = &actual[i];
systrace_sysent_t *s = &sysent[i];
if (LOADABLE_SYSCALL(a) && !LOADED_SYSCALL(a))
continue;
if (a->sy_callc == dtrace_systrace_syscall)
continue;
#ifdef _SYSCALL32_IMPL
if (a->sy_callc == dtrace_systrace_syscall32)
continue;
#endif
s->stsy_underlying = a->sy_callc;
}
}
/*
* "Decode" rv for use in the call to dtrace_probe()
*/
if (rval == ERESTART) {
munged_rv0 = -1LL; /* System call will be reissued in user mode. Make DTrace report a -1 return. */
munged_rv1 = -1LL;
} else if (rval != EJUSTRETURN) {
if (rval) {
munged_rv0 = -1LL; /* Mimic what libc will do. */
munged_rv1 = -1LL;
} else {
switch (sy->stsy_return_type) {
case _SYSCALL_RET_INT_T:
munged_rv0 = rv[0];
munged_rv1 = rv[1];
break;
case _SYSCALL_RET_UINT_T:
munged_rv0 = ((u_int)rv[0]);
munged_rv1 = ((u_int)rv[1]);
break;
case _SYSCALL_RET_OFF_T:
case _SYSCALL_RET_UINT64_T:
munged_rv0 = *(u_int64_t *)rv;
munged_rv1 = 0LL;
break;
case _SYSCALL_RET_ADDR_T:
case _SYSCALL_RET_SIZE_T:
case _SYSCALL_RET_SSIZE_T:
munged_rv0 = *(user_addr_t *)rv;
munged_rv1 = 0LL;
break;
case _SYSCALL_RET_NONE:
munged_rv0 = 0LL;
munged_rv1 = 0LL;
break;
default:
munged_rv0 = 0LL;
munged_rv1 = 0LL;
break;
}
}
} else {
munged_rv0 = 0LL;
munged_rv1 = 0LL;
}
(*systrace_probe)(id, munged_rv0, munged_rv0, munged_rv1, (uint64_t)rval, 0);
}
}
#endif /* __APPLE__ */
#define SYSTRACE_SHIFT 16
#define SYSTRACE_ISENTRY(x) ((int)(x) >> SYSTRACE_SHIFT)
#define SYSTRACE_SYSNUM(x) ((int)(x) & ((1 << SYSTRACE_SHIFT) - 1))
#define SYSTRACE_ENTRY(id) ((1 << SYSTRACE_SHIFT) | (id))
#define SYSTRACE_RETURN(id) (id)
#if ((1 << SYSTRACE_SHIFT) <= NSYSCALL)
#error 1 << SYSTRACE_SHIFT must exceed number of system calls
#endif
static dev_info_t *systrace_devi;
static dtrace_provider_id_t systrace_id;
#if !defined (__APPLE__)
static void
systrace_init(struct sysent *actual, systrace_sysent_t **interposed)
{
systrace_sysent_t *sysent = *interposed;
int i;
if (sysent == NULL) {
*interposed = sysent = kmem_zalloc(sizeof (systrace_sysent_t) *
NSYSCALL, KM_SLEEP);
}
for (i = 0; i < NSYSCALL; i++) {
struct sysent *a = &actual[i];
systrace_sysent_t *s = &sysent[i];
if (LOADABLE_SYSCALL(a) && !LOADED_SYSCALL(a))
continue;
if (a->sy_callc == dtrace_systrace_syscall)
continue;
#ifdef _SYSCALL32_IMPL
if (a->sy_callc == dtrace_systrace_syscall32)
continue;
#endif
s->stsy_underlying = a->sy_callc;
}
}
#else
#define systrace_init _systrace_init /* Avoid name clash with Darwin automagic conf symbol */
static void
systrace_init(struct sysent *actual, systrace_sysent_t **interposed)
{
systrace_sysent_t *ssysent = *interposed; /* Avoid sysent shadow warning
from bsd/sys/sysent.h */
int i;
if (ssysent == NULL) {
*interposed = ssysent = kmem_zalloc(sizeof (systrace_sysent_t) *
NSYSCALL, KM_SLEEP);
}
for (i = 0; i < NSYSCALL; i++) {
struct sysent *a = &actual[i];
systrace_sysent_t *s = &ssysent[i];
if (LOADABLE_SYSCALL(a) && !LOADED_SYSCALL(a))
continue;
if (a->sy_callc == dtrace_systrace_syscall)
continue;
#ifdef _SYSCALL32_IMPL
if (a->sy_callc == dtrace_systrace_syscall32)
continue;
#endif
s->stsy_underlying = a->sy_callc;
s->stsy_return_type = a->sy_return_type;
}
lck_mtx_init(&dtrace_systrace_lock, dtrace_lck_grp, dtrace_lck_attr);
}
static void
machtrace_init(const mach_trap_t *actual, machtrace_sysent_t **interposed)
{
machtrace_sysent_t *msysent = *interposed;
int i;
if (msysent == NULL) {
*interposed = msysent = kmem_zalloc(sizeof (machtrace_sysent_t) *
NSYSCALL, KM_SLEEP);
}
for (i = 0; i < NSYSCALL; i++) {
const mach_trap_t *a = &actual[i];
machtrace_sysent_t *s = &msysent[i];
if (LOADABLE_SYSCALL(a) && !LOADED_SYSCALL(a))
continue;
if (a->mach_trap_function == (mach_call_t)(dtrace_machtrace_syscall))
continue;
s->stsy_underlying = a->mach_trap_function;
}
}
/*
* Save the system call arguments in a safe place.
*
* On the i386 kernel:
*
* Copy the users args prior to changing the stack or stack pointer.
* This is so /proc will be able to get a valid copy of the
* args from the user stack even after the user stack has been changed.
* Note that the kernel stack copy of the args may also have been
* changed by a system call handler which takes C-style arguments.
*
* Note that this may be called by stop() from trap(). In that case
* t_sysnum will be zero (syscall_exit clears it), so no args will be
* copied.
*
* On the amd64 kernel:
*
* For 64-bit applications, lwp->lwp_ap normally points to %rdi..%r9
* in the reg structure. If the user is going to change the argument
* registers, rax, or the stack and might want to get the args (for
* /proc tracing), it must copy the args elsewhere via save_syscall_args().
*
* For 32-bit applications, lwp->lwp_ap normally points to a copy of
* the system call arguments on the kernel stack made from the user
* stack. Copy the args prior to change the stack or stack pointer.
* This is so /proc will be able to get a valid copy of the args
* from the user stack even after that stack has been changed.
*
* This may be called from stop() even when we're not in a system call.
* Since there's no easy way to tell, this must be safe (not panic).
* If the copyins get data faults, return non-zero.
*/
int
save_syscall_args()
{
kthread_t *t = curthread;
klwp_t *lwp = ttolwp(t);
uint_t code = t->t_sysnum;
uint_t nargs;
if (lwp->lwp_argsaved || code == 0)
return (0); /* args already saved or not needed */
if (code >= NSYSCALL) {
nargs = 0; /* illegal syscall */
} else {
struct sysent *se = LWP_GETSYSENT(lwp);
struct sysent *callp = se + code;
nargs = callp->sy_narg;
if (LOADABLE_SYSCALL(callp) && nargs == 0) {
krwlock_t *module_lock;
/*
* Find out how many arguments the system
* call uses.
*
* We have the property that loaded syscalls
* never change the number of arguments they
* use after they've been loaded once. This
* allows us to stop for /proc tracing without
* holding the module lock.
* /proc is assured that sy_narg is valid.
*/
module_lock = lock_syscall(se, code);
nargs = callp->sy_narg;
rw_exit(module_lock);
}
}
/*
* Fetch the system call arguments.
*/
if (nargs == 0)
goto out;
ASSERT(nargs <= MAXSYSARGS);
if (lwp_getdatamodel(lwp) == DATAMODEL_NATIVE) {
#if defined(_LP64)
struct regs *rp = lwptoregs(lwp);
lwp->lwp_arg[0] = rp->r_rdi;
lwp->lwp_arg[1] = rp->r_rsi;
lwp->lwp_arg[2] = rp->r_rdx;
lwp->lwp_arg[3] = rp->r_rcx;
lwp->lwp_arg[4] = rp->r_r8;
lwp->lwp_arg[5] = rp->r_r9;
if (nargs > 6 && copyin_args(rp, &lwp->lwp_arg[6], nargs - 6))
return (-1);
} else {
#endif
if (COPYIN_ARGS32(lwptoregs(lwp), lwp->lwp_arg, nargs))
return (-1);
}
out:
lwp->lwp_ap = lwp->lwp_arg;
lwp->lwp_argsaved = 1;
t->t_post_sys = 1; /* so lwp_ap will be reset */
return (0);
}
/*
* Save the system call arguments in a safe place.
* lwp->lwp_ap normally points to the out regs in the reg structure.
* If the user is going to change the out registers, g1, or the stack,
* and might want to get the args (for /proc tracing), it must copy
* the args elsewhere via save_syscall_args().
*
* This may be called from stop() even when we're not in a system call.
* Since there's no easy way to tell, this must be safe (not panic).
* If the copyins get data faults, return non-zero.
*/
int
save_syscall_args()
{
kthread_t *t = curthread;
klwp_t *lwp = ttolwp(t);
struct regs *rp = lwptoregs(lwp);
uint_t code = t->t_sysnum;
uint_t nargs;
int i;
caddr_t ua;
model_t datamodel;
if (lwp->lwp_argsaved || code == 0)
return (0); /* args already saved or not needed */
if (code >= NSYSCALL) {
nargs = 0; /* illegal syscall */
} else {
struct sysent *se = LWP_GETSYSENT(lwp);
struct sysent *callp = se + code;
nargs = callp->sy_narg;
if (LOADABLE_SYSCALL(callp) && nargs == 0) {
krwlock_t *module_lock;
/*
* Find out how many arguments the system
* call uses.
*
* We have the property that loaded syscalls
* never change the number of arguments they
* use after they've been loaded once. This
* allows us to stop for /proc tracing without
* holding the module lock.
* /proc is assured that sy_narg is valid.
*/
module_lock = lock_syscall(se, code);
nargs = callp->sy_narg;
rw_exit(module_lock);
}
}
/*
* Fetch the system call arguments.
*/
if (nargs == 0)
goto out;
ASSERT(nargs <= MAXSYSARGS);
if ((datamodel = lwp_getdatamodel(lwp)) == DATAMODEL_ILP32) {
if (rp->r_g1 == 0) { /* indirect syscall */
lwp->lwp_arg[0] = (uint32_t)rp->r_o1;
lwp->lwp_arg[1] = (uint32_t)rp->r_o2;
lwp->lwp_arg[2] = (uint32_t)rp->r_o3;
lwp->lwp_arg[3] = (uint32_t)rp->r_o4;
lwp->lwp_arg[4] = (uint32_t)rp->r_o5;
if (nargs > 5) {
ua = (caddr_t)(uintptr_t)(caddr32_t)(uintptr_t)
(rp->r_sp + MINFRAME32);
for (i = 5; i < nargs; i++) {
uint32_t a;
if (fuword32(ua, &a) != 0)
return (-1);
lwp->lwp_arg[i] = a;
ua += sizeof (a);
}
}
} else {
lwp->lwp_arg[0] = (uint32_t)rp->r_o0;
lwp->lwp_arg[1] = (uint32_t)rp->r_o1;
lwp->lwp_arg[2] = (uint32_t)rp->r_o2;
lwp->lwp_arg[3] = (uint32_t)rp->r_o3;
lwp->lwp_arg[4] = (uint32_t)rp->r_o4;
lwp->lwp_arg[5] = (uint32_t)rp->r_o5;
if (nargs > 6) {
ua = (caddr_t)(uintptr_t)(caddr32_t)(uintptr_t)
(rp->r_sp + MINFRAME32);
for (i = 6; i < nargs; i++) {
uint32_t a;
if (fuword32(ua, &a) != 0)
return (-1);
lwp->lwp_arg[i] = a;
ua += sizeof (a);
}
}
}
} else {
ASSERT(datamodel == DATAMODEL_LP64);
lwp->lwp_arg[0] = rp->r_o0;
lwp->lwp_arg[1] = rp->r_o1;
lwp->lwp_arg[2] = rp->r_o2;
lwp->lwp_arg[3] = rp->r_o3;
lwp->lwp_arg[4] = rp->r_o4;
lwp->lwp_arg[5] = rp->r_o5;
if (nargs > 6) {
ua = (caddr_t)rp->r_sp + MINFRAME + STACK_BIAS;
for (i = 6; i < nargs; i++) {
unsigned long a;
if (fulword(ua, &a) != 0)
return (-1);
lwp->lwp_arg[i] = a;
ua += sizeof (a);
}
}
}
out:
lwp->lwp_ap = lwp->lwp_arg;
lwp->lwp_argsaved = 1;
t->t_post_sys = 1; /* so lwp_ap will be reset */
return (0);
}
