33#include <sys/kernel.h>
35#include <sys/module.h>
38#include <sys/resourcevar.h>
40#include <sys/syscall.h>
41#include <sys/sysent.h>
42#include <sys/sysproto.h>
44#include <machine/atomic.h>
56 return (
nosys(td, args));
63 return (
nosys(td, args));
72 oldcnt = se->sy_thrcnt;
73 KASSERT((oldcnt & SY_THR_STATIC) == 0,
74 (
"drain on static syscall"));
75 cnt = oldcnt | SY_THR_DRAINING;
76 }
while (atomic_cmpset_acq_32(&se->sy_thrcnt, oldcnt, cnt) == 0);
77 while (atomic_cmpset_32(&se->sy_thrcnt, SY_THR_DRAINING,
87 KASSERT((se->sy_thrcnt & SY_THR_STATIC) == 0,
88 (
"%s: not a static syscall", __func__));
91 oldcnt = se->sy_thrcnt;
92 if ((oldcnt & (SY_THR_DRAINING | SY_THR_ABSENT)) != 0)
94 cnt = oldcnt + SY_THR_INCR;
95 }
while (atomic_cmpset_acq_32(&se->sy_thrcnt, oldcnt, cnt) == 0);
102 uint32_t cnt, oldcnt;
104 KASSERT((se->sy_thrcnt & SY_THR_STATIC) == 0,
105 (
"%s: not a static syscall", __func__));
108 oldcnt = se->sy_thrcnt;
109 cnt = oldcnt - SY_THR_INCR;
110 }
while (atomic_cmpset_rel_32(&se->sy_thrcnt, oldcnt, cnt) == 0);
119 if ((
flags & ~SY_THR_STATIC) != 0)
122 if (*offset == NO_SYSCALL) {
123 for (i = 1; i < SYS_MAXSYSCALL; ++i)
124 if (sysents[i].sy_call == (sy_call_t *)
lkmnosys)
126 if (i == SYS_MAXSYSCALL)
129 }
else if (*offset < 0 || *offset >= SYS_MAXSYSCALL) {
131 }
else if (sysents[*offset].sy_call != (sy_call_t *)
lkmnosys &&
132 sysents[*offset].sy_call != (sy_call_t *)
lkmressys) {
133 KASSERT(sysents[*offset].sy_call != NULL,
134 (
"undefined syscall %d", *offset));
138 KASSERT(sysents[*offset].sy_thrcnt == SY_THR_ABSENT,
139 (
"dynamic syscall is not protected"));
140 *old_sysent = sysents[*offset];
141 new_sysent->sy_thrcnt = SY_THR_ABSENT;
142 sysents[*offset] = *new_sysent;
143 atomic_store_rel_32(&sysents[*offset].sy_thrcnt,
flags);
149 const struct sysent *old_sysent)
156 se = &sysents[offset];
157 if ((se->sy_thrcnt & SY_THR_STATIC) != 0)
160 sysents[offset] = *old_sysent;
175 struct syscall_module_data *
data = arg;
188 ms.intval = *
data->offset;
193 error =
data->chainevh(mod, what,
data->chainarg);
201 if (
data->offset == NULL)
203 if (
data->chainevh) {
204 error =
data->chainevh(mod, what,
data->chainarg);
213 return (
data->chainevh(mod, what,
data->chainarg));
229 struct syscall_helper_data *sd,
int flags)
231 struct syscall_helper_data *sd1;
234 for (sd1 = sd; sd1->syscall_no != NO_SYSCALL; sd1++) {
236 &sd1->new_sysent, &sd1->old_sysent,
flags);
255 struct syscall_helper_data *sd)
257 struct syscall_helper_data *sd1;
259 for (sd1 = sd; sd1->registered != 0; sd1++) {
void module_setspecific(module_t mod, modspecific_t *datap)
int nosys(struct thread *td, struct nosys_args *args)
static void syscall_thread_drain(struct sysent *se)
int kern_syscall_deregister(struct sysent *sysents, int offset, const struct sysent *old_sysent)
int syscall_module_handler(struct module *mod, int what, void *arg)
int lkmnosys(struct thread *td, struct nosys_args *args)
int kern_syscall_helper_unregister(struct sysent *sysents, struct syscall_helper_data *sd)
int kern_syscall_module_handler(struct sysent *sysents, struct module *mod, int what, void *arg)
int lkmressys(struct thread *td, struct nosys_args *args)
int syscall_helper_unregister(struct syscall_helper_data *sd)
int kern_syscall_register(struct sysent *sysents, int *offset, struct sysent *new_sysent, struct sysent *old_sysent, int flags)
void syscall_thread_exit(struct thread *td, struct sysent *se)
int kern_syscall_helper_register(struct sysent *sysents, struct syscall_helper_data *sd, int flags)
int syscall_thread_enter(struct thread *td, struct sysent *se)
int syscall_helper_register(struct syscall_helper_data *sd, int flags)