7 files changed, 174 insertions, 158 deletions

diff --git a/arch/sh/include/asm/thread_info.h b/arch/sh/include/asm/thread_info.h
index 03d1e386670..0a894cafb1d 100644
--- a/arch/sh/include/asm/thread_info.h
+++ b/arch/sh/include/asm/thread_info.h
@@ -119,10 +119,11 @@ static inline struct thread_info *current_thread_info(void)
 #define TIF_SINGLESTEP          4       /* singlestepping active */
 #define TIF_SYSCALL_AUDIT       5       /* syscall auditing active */
 #define TIF_SECCOMP             6       /* secure computing */
+#define TIF_NOTIFY_RESUME       7       /* callback before returning to user */
 #define TIF_USEDFPU             16      /* FPU was used by this task this quantum (SMP) */
 #define TIF_POLLING_NRFLAG      17      /* true if poll_idle() is polling TIF_NEED_RESCHED */
 #define TIF_MEMDIE              18
-#define TIF_FREEZE              19
+#define TIF_FREEZE              19      /* Freezing for suspend */
 
 #define _TIF_SYSCALL_TRACE      (1 << TIF_SYSCALL_TRACE)
 #define _TIF_SIGPENDING         (1 << TIF_SIGPENDING)
@@ -131,6 +132,7 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_SINGLESTEP         (1 << TIF_SINGLESTEP)
 #define _TIF_SYSCALL_AUDIT      (1 << TIF_SYSCALL_AUDIT)
 #define _TIF_SECCOMP            (1 << TIF_SECCOMP)
+#define _TIF_NOTIFY_RESUME      (1 << TIF_NOTIFY_RESUME)
 #define _TIF_USEDFPU            (1 << TIF_USEDFPU)
 #define _TIF_POLLING_NRFLAG     (1 << TIF_POLLING_NRFLAG)
 #define _TIF_FREEZE             (1 << TIF_FREEZE)
@@ -146,9 +148,10 @@ static inline struct thread_info *current_thread_info(void)
                                  _TIF_SYSCALL_AUDIT | _TIF_SECCOMP)
 
 /* work to do on any return to u-space */
-#define _TIF_ALLWORK_MASK       (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING    | \
-                                 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT | \
-                                 _TIF_SINGLESTEP    | _TIF_RESTORE_SIGMASK)
+#define _TIF_ALLWORK_MASK       (_TIF_SYSCALL_TRACE | _TIF_SIGPENDING      | \
+                                 _TIF_NEED_RESCHED  | _TIF_SYSCALL_AUDIT   | \
+                                 _TIF_SINGLESTEP    | _TIF_RESTORE_SIGMASK | \
+                                 _TIF_NOTIFY_RESUME)
 
 /* work to do on interrupt/exception return */
 #define _TIF_WORK_MASK          (_TIF_ALLWORK_MASK & ~(_TIF_SYSCALL_TRACE | \
diff --git a/arch/sh/kernel/cpu/sh5/entry.S b/arch/sh/kernel/cpu/sh5/entry.S
index bba331d5ef7..04c7da96814 100644
--- a/arch/sh/kernel/cpu/sh5/entry.S
+++ b/arch/sh/kernel/cpu/sh5/entry.S
@@ -987,11 +987,11 @@ work_resched:
 work_notifysig:
         gettr   tr1, LINK
 
-        movi    do_signal, r6
+        movi    do_notify_resume, r6
         ptabs   r6, tr0
         or      SP, ZERO, r2
-        or      ZERO, ZERO, r3
-        blink   tr0, LINK           /* Call do_signal(regs, 0), return here */
+        or      r7, ZERO, r3
+        blink   tr0, LINK           /* Call do_notify_resume(regs, current_thread_info->flags), return here */
 
 restore_all:
         /* Do prefetches */
@@ -1305,13 +1305,15 @@ syscall_allowed:
         beq/l   r6, ZERO, tr0
 
         /* Trace it by calling syscall_trace before and after */
-        movi    syscall_trace, r4
+        movi    do_syscall_trace_enter, r4
         or      SP, ZERO, r2
-        or      ZERO, ZERO, r3
         ptabs   r4, tr0
         blink   tr0, LINK
 
-        /* Reload syscall number as r5 is trashed by syscall_trace */
+        /* Save the retval */
+        st.q    SP, FRAME_R(2), r2
+
+        /* Reload syscall number as r5 is trashed by do_syscall_trace_enter */
         ld.q    SP, FRAME_S(FSYSCALL_ID), r5
         andi    r5, 0x1ff, r5
 
@@ -1343,9 +1345,8 @@ syscall_ret_trace:
         /* We get back here only if under trace */
         st.q    SP, FRAME_R(9), r2      /* Save return value */
 
-        movi    syscall_trace, LINK
+        movi    do_syscall_trace_leave, LINK
         or      SP, ZERO, r2
-        movi    1, r3
         ptabs   LINK, tr0
         blink   tr0, LINK
 
diff --git a/arch/sh/kernel/entry-common.S b/arch/sh/kernel/entry-common.S
index a34417c8ee0..0bc17def55a 100644
--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -211,10 +211,8 @@ syscall_exit_work:
          nop
 #endif
         sti
-        ! XXX setup arguments...
         mov     r15, r4
-        mov     #1, r5
-        mov.l   4f, r0                  ! do_syscall_trace
+        mov.l   8f, r0                  ! do_syscall_trace_leave
         jsr     @r0
          nop
         bra     resume_userspace
@@ -223,12 +221,11 @@ syscall_exit_work:
         .align  2
 syscall_trace_entry:
         !                       Yes it is traced.
-        ! XXX setup arguments...
         mov     r15, r4
-        mov     #0, r5
-        mov.l   4f, r11         ! Call do_syscall_trace which notifies
+        mov.l   7f, r11         ! Call do_syscall_trace_enter which notifies
         jsr     @r11            ! superior (will chomp R[0-7])
          nop
+        mov.l   r0, @(OFF_R0,r15)       ! Save return value
         !                       Reload R0-R4 from kernel stack, where the
         !                       parent may have modified them using
         !                       ptrace(POKEUSR).  (Note that R0-R2 are
@@ -389,8 +386,9 @@ syscall_exit:
 #endif
 2:      .long   NR_syscalls
 3:      .long   sys_call_table
-4:      .long   do_syscall_trace
 #ifdef CONFIG_TRACE_IRQFLAGS
 5:      .long   trace_hardirqs_on
 6:      .long   trace_hardirqs_off
 #endif
+7:      .long   do_syscall_trace_enter
+8:      .long   do_syscall_trace_leave
diff --git a/arch/sh/kernel/ptrace_32.c b/arch/sh/kernel/ptrace_32.c
index ff66f97c564..f48769b23bd 100644
--- a/arch/sh/kernel/ptrace_32.c
+++ b/arch/sh/kernel/ptrace_32.c
@@ -21,6 +21,7 @@
 #include <linux/io.h>
 #include <linux/audit.h>
 #include <linux/seccomp.h>
+#include <linux/tracehook.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/system.h>
@@ -216,41 +217,38 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
         return ret;
 }
 
-asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 {
-        struct task_struct *tsk = current;
+        long ret = 0;
 
         secure_computing(regs->regs[0]);
 
-        if (unlikely(current->audit_context) && entryexit)
-                audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
-                                   regs->regs[0]);
-
-        if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
-            !test_thread_flag(TIF_SINGLESTEP))
-                goto out;
-        if (!(tsk->ptrace & PT_PTRACED))
-                goto out;
-
-        /* the 0x80 provides a way for the tracing parent to distinguish
-           between a syscall stop and SIGTRAP delivery */
-        ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) &&
-                                 !test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0));
-
-        /*
-         * this isn't the same as continuing with a signal, but it will do
-         * for normal use.  strace only continues with a signal if the
-         * stopping signal is not SIGTRAP.  -brl
-         */
-        if (tsk->exit_code) {
-                send_sig(tsk->exit_code, tsk, 1);
-                tsk->exit_code = 0;
-        }
+        if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+            tracehook_report_syscall_entry(regs))
+                /*
+                 * Tracing decided this syscall should not happen.
+                 * We'll return a bogus call number to get an ENOSYS
+                 * error, but leave the original number in regs->regs[0].
+                 */
+                ret = -1L;
 
-out:
-        if (unlikely(current->audit_context) && !entryexit)
+        if (unlikely(current->audit_context))
                 audit_syscall_entry(AUDIT_ARCH_SH, regs->regs[3],
                                     regs->regs[4], regs->regs[5],
                                     regs->regs[6], regs->regs[7]);
 
+        return ret ?: regs->regs[0];
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+        int step;
+
+        if (unlikely(current->audit_context))
+                audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]),
+                                   regs->regs[0]);
+
+        step = test_thread_flag(TIF_SINGLESTEP);
+        if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall_exit(regs, step);
 }
diff --git a/arch/sh/kernel/ptrace_64.c b/arch/sh/kernel/ptrace_64.c
index 108f3962e39..236d8bef9cc 100644
--- a/arch/sh/kernel/ptrace_64.c
+++ b/arch/sh/kernel/ptrace_64.c
@@ -28,6 +28,7 @@
 #include <linux/syscalls.h>
 #include <linux/audit.h>
 #include <linux/seccomp.h>
+#include <linux/tracehook.h>
 #include <asm/io.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -221,40 +222,37 @@ asmlinkage int sh64_ptrace(long request, long pid, long addr, long data)
         return sys_ptrace(request, pid, addr, data);
 }
 
-asmlinkage void syscall_trace(struct pt_regs *regs, int entryexit)
+asmlinkage long long do_syscall_trace_enter(struct pt_regs *regs)
 {
-        struct task_struct *tsk = current;
+        long long ret = 0;
 
         secure_computing(regs->regs[9]);
 
-        if (unlikely(current->audit_context) && entryexit)
-                audit_syscall_exit(AUDITSC_RESULT(regs->regs[9]),
-                                   regs->regs[9]);
-
-        if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
-            !test_thread_flag(TIF_SINGLESTEP))
-                goto out;
-        if (!(tsk->ptrace & PT_PTRACED))
-                goto out;
-
-        ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) &&
-                                !test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0));
-
-        /*
-         * this isn't the same as continuing with a signal, but it will do
-         * for normal use.  strace only continues with a signal if the
-         * stopping signal is not SIGTRAP.  -brl
-         */
-        if (tsk->exit_code) {
-                send_sig(tsk->exit_code, tsk, 1);
-                tsk->exit_code = 0;
-        }
+        if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+            tracehook_report_syscall_entry(regs))
+                /*
+                 * Tracing decided this syscall should not happen.
+                 * We'll return a bogus call number to get an ENOSYS
+                 * error, but leave the original number in regs->regs[0].
+                 */
+                ret = -1LL;
 
-out:
-        if (unlikely(current->audit_context) && !entryexit)
+        if (unlikely(current->audit_context))
                 audit_syscall_entry(AUDIT_ARCH_SH, regs->regs[1],
                                     regs->regs[2], regs->regs[3],
                                     regs->regs[4], regs->regs[5]);
+
+        return ret ?: regs->regs[9];
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+        if (unlikely(current->audit_context))
+                audit_syscall_exit(AUDITSC_RESULT(regs->regs[9]),
+                                   regs->regs[9]);
+
+        if (test_thread_flag(TIF_SYSCALL_TRACE))
+                tracehook_report_syscall_exit(regs, 0);
 }
 
 /* Called with interrupts disabled */
diff --git a/arch/sh/kernel/signal_32.c b/arch/sh/kernel/signal_32.c
index 4bbbde895a5..51689d29ad4 100644
--- a/arch/sh/kernel/signal_32.c
+++ b/arch/sh/kernel/signal_32.c
@@ -24,6 +24,7 @@
 #include <linux/binfmts.h>
 #include <linux/freezer.h>
 #include <linux/io.h>
+#include <linux/tracehook.h>
 #include <asm/system.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
@@ -507,14 +508,13 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
                 switch (regs->regs[0]) {
                         case -ERESTART_RESTARTBLOCK:
                         case -ERESTARTNOHAND:
+                        no_system_call_restart:
                                 regs->regs[0] = -EINTR;
                                 break;
 
                         case -ERESTARTSYS:
-                                if (!(ka->sa.sa_flags & SA_RESTART)) {
-                                        regs->regs[0] = -EINTR;
-                                        break;
-                                }
+                                if (!(ka->sa.sa_flags & SA_RESTART))
+                                        goto no_system_call_restart;
                         /* fallthrough */
                         case -ERESTARTNOINTR:
                                 regs->regs[0] = save_r0;
@@ -589,12 +589,15 @@ static void do_signal(struct pt_regs *regs, unsigned int save_r0)
                          * clear the TIF_RESTORE_SIGMASK flag */
                         if (test_thread_flag(TIF_RESTORE_SIGMASK))
                                 clear_thread_flag(TIF_RESTORE_SIGMASK);
+
+                        tracehook_signal_handler(signr, &info, &ka, regs,
+                                        test_thread_flag(TIF_SINGLESTEP));
                 }
 
                 return;
         }
 
- no_signal:
+no_signal:
         /* Did we come from a system call? */
         if (regs->tra >= 0) {
                 /* Restart the system call - no handlers present */
@@ -618,9 +621,14 @@ static void do_signal(struct pt_regs *regs, unsigned int save_r0)
 }
 
 asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
-                                 __u32 thread_info_flags)
+                                 unsigned long thread_info_flags)
 {
         /* deal with pending signal delivery */
-        if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
+        if (thread_info_flags & _TIF_SIGPENDING)
                 do_signal(regs, save_r0);
+
+        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+                clear_thread_flag(TIF_NOTIFY_RESUME);
+                tracehook_notify_resume(regs);
+        }
 }
diff --git a/arch/sh/kernel/signal_64.c b/arch/sh/kernel/signal_64.c
index 552eb810cd8..1d62dfef77f 100644
--- a/arch/sh/kernel/signal_64.c
+++ b/arch/sh/kernel/signal_64.c
@@ -22,6 +22,7 @@
 #include <linux/ptrace.h>
 #include <linux/unistd.h>
 #include <linux/stddef.h>
+#include <linux/tracehook.h>
 #include <asm/ucontext.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -42,7 +43,84 @@
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
-asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ *
+ * Note that we go through the signals twice: once to check the signals that
+ * the kernel can handle, and then we build all the user-level signal handling
+ * stack-frames in one go after that.
+ */
+static int do_signal(struct pt_regs *regs, sigset_t *oldset)
+{
+        siginfo_t info;
+        int signr;
+        struct k_sigaction ka;
+
+        /*
+         * We want the common case to go fast, which
+         * is why we may in certain cases get here from
+         * kernel mode. Just return without doing anything
+         * if so.
+         */
+        if (!user_mode(regs))
+                return 1;
+
+        if (try_to_freeze())
+                goto no_signal;
+
+        if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                oldset = &current->saved_sigmask;
+        else if (!oldset)
+                oldset = &current->blocked;
+
+        signr = get_signal_to_deliver(&info, &ka, regs, 0);
+
+        if (signr > 0) {
+                /* Whee!  Actually deliver the signal.  */
+                handle_signal(signr, &info, &ka, oldset, regs);
+
+                /*
+                 * If a signal was successfully delivered, the saved sigmask
+                 * is in its frame, and we can clear the TIF_RESTORE_SIGMASK
+                 * flag.
+                 */
+                if (test_thread_flag(TIF_RESTORE_SIGMASK))
+                        clear_thread_flag(TIF_RESTORE_SIGMASK);
+
+                tracehook_signal_handler(signr, &info, &ka, regs, 0);
+                return 1;
+        }
+
+no_signal:
+        /* Did we come from a system call? */
+        if (regs->syscall_nr >= 0) {
+                /* Restart the system call - no handlers present */
+                switch (regs->regs[REG_RET]) {
+                case -ERESTARTNOHAND:
+                case -ERESTARTSYS:
+                case -ERESTARTNOINTR:
+                        /* Decode Syscall # */
+                        regs->regs[REG_RET] = regs->syscall_nr;
+                        regs->pc -= 4;
+                        break;
+
+                case -ERESTART_RESTARTBLOCK:
+                        regs->regs[REG_RET] = __NR_restart_syscall;
+                        regs->pc -= 4;
+                        break;
+                }
+        }
+
+        /* No signal to deliver -- put the saved sigmask back */
+        if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+                clear_thread_flag(TIF_RESTORE_SIGMASK);
+                sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+        }
+
+        return 0;
+}
 
 /*
  * Atomically swap in the new signal mask, and wait for a signal.
@@ -643,14 +721,13 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
                 switch (regs->regs[REG_RET]) {
                         case -ERESTART_RESTARTBLOCK:
                         case -ERESTARTNOHAND:
+                        no_system_call_restart:
                                 regs->regs[REG_RET] = -EINTR;
                                 break;
 
                         case -ERESTARTSYS:
-                                if (!(ka->sa.sa_flags & SA_RESTART)) {
-                                        regs->regs[REG_RET] = -EINTR;
-                                        break;
-                                }
+                                if (!(ka->sa.sa_flags & SA_RESTART))
+                                        goto no_system_call_restart;
                         /* fallthrough */
                         case -ERESTARTNOINTR:
                                 /* Decode syscall # */
@@ -673,80 +750,13 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
         spin_unlock_irq(&current->sighand->siglock);
 }
 
-/*
- * Note that 'init' is a special process: it doesn't get signals it doesn't
- * want to handle. Thus you cannot kill init even with a SIGKILL even by
- * mistake.
- *
- * Note that we go through the signals twice: once to check the signals that
- * the kernel can handle, and then we build all the user-level signal handling
- * stack-frames in one go after that.
- */
-int do_signal(struct pt_regs *regs, sigset_t *oldset)
+asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags)
 {
-        siginfo_t info;
-        int signr;
-        struct k_sigaction ka;
-
-        /*
-         * We want the common case to go fast, which
-         * is why we may in certain cases get here from
-         * kernel mode. Just return without doing anything
-         * if so.
-         */
-        if (!user_mode(regs))
-                return 1;
-
-        if (try_to_freeze())
-                goto no_signal;
-
-        if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                oldset = &current->saved_sigmask;
-        else if (!oldset)
-                oldset = &current->blocked;
-
-        signr = get_signal_to_deliver(&info, &ka, regs, 0);
-
-        if (signr > 0) {
-                /* Whee!  Actually deliver the signal.  */
-                handle_signal(signr, &info, &ka, oldset, regs);
+        if (thread_info_flags & _TIF_SIGPENDING)
+                do_signal(regs, 0);
 
-                /*
-                 * If a signal was successfully delivered, the saved sigmask
-                 * is in its frame, and we can clear the TIF_RESTORE_SIGMASK
-                 * flag.
-                 */
-                if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                        clear_thread_flag(TIF_RESTORE_SIGMASK);
-
-                return 1;
+        if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+                clear_thread_flag(TIF_NOTIFY_RESUME);
+                tracehook_notify_resume(regs);
         }
-
-no_signal:
-        /* Did we come from a system call? */
-        if (regs->syscall_nr >= 0) {
-                /* Restart the system call - no handlers present */
-                switch (regs->regs[REG_RET]) {
-                case -ERESTARTNOHAND:
-                case -ERESTARTSYS:
-                case -ERESTARTNOINTR:
-                        /* Decode Syscall # */
-                        regs->regs[REG_RET] = regs->syscall_nr;
-                        regs->pc -= 4;
-                        break;
-
-                case -ERESTART_RESTARTBLOCK:
-                        regs->regs[REG_RET] = __NR_restart_syscall;
-                        regs->pc -= 4;
-                        break;
-                }
-        }
-
-        /* No signal to deliver -- put the saved sigmask back */
-        if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
-                clear_thread_flag(TIF_RESTORE_SIGMASK);
-                sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
-        }
-
-        return 0;
 }