asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
- long ret;
+ long ret = 0;
/* Do the secure computing check first. */
secure_computing(regs->gprs[2]);
* The sysc_tracesys code in entry.S stored the system
* call number to gprs[2].
*/
- ret = regs->gprs[2];
if (test_thread_flag(TIF_SYSCALL_TRACE) &&
(tracehook_report_syscall_entry(regs) ||
regs->gprs[2] >= NR_syscalls)) {
regs->gprs[2], regs->orig_gpr2,
regs->gprs[3], regs->gprs[4],
regs->gprs[5]);
- return ret;
+ return ret ?: regs->gprs[2];
}
asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
#endif
return &user_s390_view;
}
+
+static const char *gpr_names[NUM_GPRS] = {
+ "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
+ "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
+};
+
+unsigned long regs_get_register(struct pt_regs *regs, unsigned int offset)
+{
+ if (offset >= NUM_GPRS)
+ return 0;
+ return regs->gprs[offset];
+}
+
+int regs_query_register_offset(const char *name)
+{
+ unsigned long offset;
+
+ if (!name || *name != 'r')
+ return -EINVAL;
+ if (strict_strtoul(name + 1, 10, &offset))
+ return -EINVAL;
+ if (offset >= NUM_GPRS)
+ return -EINVAL;
+ return offset;
+}
+
+const char *regs_query_register_name(unsigned int offset)
+{
+ if (offset >= NUM_GPRS)
+ return NULL;
+ return gpr_names[offset];
+}
+
+static int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ unsigned long ksp = kernel_stack_pointer(regs);
+
+ return (addr & ~(THREAD_SIZE - 1)) == (ksp & ~(THREAD_SIZE - 1));
+}
+
+/**
+ * regs_get_kernel_stack_nth() - get Nth entry of the stack
+ * @regs:pt_regs which contains kernel stack pointer.
+ * @n:stack entry number.
+ *
+ * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
+ * is specifined by @regs. If the @n th entry is NOT in the kernel stack,
+ * this returns 0.
+ */
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long addr;
+
+ addr = kernel_stack_pointer(regs) + n * sizeof(long);
+ if (!regs_within_kernel_stack(regs, addr))
+ return 0;
+ return *(unsigned long *)addr;
+}