| 1 | /* $NetBSD: linux32_syscall.c,v 1.32 2015/03/07 18:41:40 christos Exp $ */ |
| 2 | |
| 3 | #include <sys/cdefs.h> |
| 4 | __KERNEL_RCSID(0, "$NetBSD: linux32_syscall.c,v 1.32 2015/03/07 18:41:40 christos Exp $" ); |
| 5 | |
| 6 | #include <sys/param.h> |
| 7 | #include <sys/systm.h> |
| 8 | #include <sys/proc.h> |
| 9 | #include <sys/signal.h> |
| 10 | #include <sys/syscall.h> |
| 11 | #include <sys/syscallvar.h> |
| 12 | |
| 13 | #include <machine/cpu.h> |
| 14 | #include <machine/psl.h> |
| 15 | #include <machine/userret.h> |
| 16 | |
| 17 | #include <compat/linux32/linux32_syscall.h> |
| 18 | #include <compat/linux32/common/linux32_errno.h> |
| 19 | |
| 20 | void linux32_syscall_intern(struct proc *); |
| 21 | void linux32_syscall(struct trapframe *); |
| 22 | |
| 23 | void |
| 24 | linux32_syscall_intern(struct proc *p) |
| 25 | { |
| 26 | |
| 27 | p->p_md.md_syscall = linux32_syscall; |
| 28 | } |
| 29 | |
| 30 | void |
| 31 | linux32_syscall(struct trapframe *frame) |
| 32 | { |
| 33 | const struct sysent *callp; |
| 34 | struct proc *p; |
| 35 | struct lwp *l; |
| 36 | int error; |
| 37 | size_t narg; |
| 38 | register32_t code, args[6]; |
| 39 | register_t rval[2]; |
| 40 | int i; |
| 41 | register_t args64[6]; |
| 42 | |
| 43 | l = curlwp; |
| 44 | p = l->l_proc; |
| 45 | |
| 46 | code = frame->tf_rax; |
| 47 | |
| 48 | LWP_CACHE_CREDS(l, p); |
| 49 | |
| 50 | callp = p->p_emul->e_sysent; |
| 51 | |
| 52 | code &= (LINUX32_SYS_NSYSENT - 1); |
| 53 | callp += code; |
| 54 | |
| 55 | /* |
| 56 | * Linux passes the args in ebx, ecx, edx, esi, edi, ebp, in |
| 57 | * increasing order. |
| 58 | */ |
| 59 | args[0] = frame->tf_rbx & 0xffffffff; |
| 60 | args[1] = frame->tf_rcx & 0xffffffff; |
| 61 | args[2] = frame->tf_rdx & 0xffffffff; |
| 62 | args[3] = frame->tf_rsi & 0xffffffff; |
| 63 | args[4] = frame->tf_rdi & 0xffffffff; |
| 64 | args[5] = frame->tf_rbp & 0xffffffff; |
| 65 | |
| 66 | if (__predict_false(p->p_trace_enabled || KDTRACE_ENTRY(callp->sy_return))) { |
| 67 | narg = callp->sy_narg; |
| 68 | if (__predict_false(narg > __arraycount(args))) |
| 69 | panic("impossible syscall narg, code %d, narg %zu" , |
| 70 | code, narg); |
| 71 | for (i = 0; i < narg; i++) |
| 72 | args64[i] = args[i] & 0xffffffff; |
| 73 | if ((error = trace_enter(code, callp, args64)) != 0) |
| 74 | goto out; |
| 75 | } |
| 76 | |
| 77 | rval[0] = 0; |
| 78 | rval[1] = 0; |
| 79 | |
| 80 | error = sy_call(callp, l, args, rval); |
| 81 | out: |
| 82 | switch (error) { |
| 83 | case 0: |
| 84 | frame->tf_rax = rval[0]; |
| 85 | frame->tf_rflags &= ~PSL_C; /* carry bit */ |
| 86 | break; |
| 87 | case ERESTART: |
| 88 | /* |
| 89 | * The offset to adjust the PC by depends on whether we entered |
| 90 | * the kernel through the trap or call gate. We pushed the |
| 91 | * size of the instruction into tf_err on entry. |
| 92 | */ |
| 93 | frame->tf_rip -= frame->tf_err; |
| 94 | break; |
| 95 | case EJUSTRETURN: |
| 96 | /* nothing to do */ |
| 97 | break; |
| 98 | default: |
| 99 | error = native_to_linux32_errno[error]; |
| 100 | frame->tf_rax = error; |
| 101 | frame->tf_rflags |= PSL_C; /* carry bit */ |
| 102 | break; |
| 103 | } |
| 104 | |
| 105 | if (__predict_false(p->p_trace_enabled || KDTRACE_ENTRY(callp->sy_return))) { |
| 106 | narg = callp->sy_narg; |
| 107 | for (i = 0; i < narg; i++) |
| 108 | args64[i] = args[i] & 0xffffffff; |
| 109 | trace_exit(code, callp, args64, rval, error); |
| 110 | } |
| 111 | userret(l); |
| 112 | } |
| 113 | |