sh: Provide the asm/syscall.h interface, needed by tracehook.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/syscall_32.h b/arch/sh/include/asm/syscall_32.h
new file mode 100644
index 0000000..54773f2
--- /dev/null
+++ b/arch/sh/include/asm/syscall_32.h
@@ -0,0 +1,110 @@
+#ifndef __ASM_SH_SYSCALL_32_H
+#define __ASM_SH_SYSCALL_32_H
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <asm/ptrace.h>
+
+/* The system call number is given by the user in %g1 */
+static inline long syscall_get_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return (regs->tra >= 0) ? regs->regs[3] : -1L;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /*
+ * XXX: This needs some thought. On SH we don't
+ * save away the original r0 value anywhere.
+ */
+}
+
+static inline bool syscall_has_error(struct pt_regs *regs)
+{
+ return (regs->sr & 0x1) ? true : false;
+}
+static inline void syscall_set_error(struct pt_regs *regs)
+{
+ regs->sr |= 0x1;
+}
+static inline void syscall_clear_error(struct pt_regs *regs)
+{
+ regs->sr &= ~0x1;
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return syscall_has_error(regs) ? regs->regs[0] : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->regs[0];
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+ struct pt_regs *regs,
+ int error, long val)
+{
+ if (error) {
+ syscall_set_error(regs);
+ regs->regs[0] = -error;
+ } else {
+ syscall_clear_error(regs);
+ regs->regs[0] = val;
+ }
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ unsigned long *args)
+{
+ /*
+ * Do this simply for now. If we need to start supporting
+ * fetching arguments from arbitrary indices, this will need some
+ * extra logic. Presently there are no in-tree users that depend
+ * on this behaviour.
+ */
+ BUG_ON(i);
+
+ /* Argument pattern is: R4, R5, R6, R7, R0, R1 */
+ switch (n) {
+ case 6: args[5] = regs->regs[1];
+ case 5: args[4] = regs->regs[0];
+ case 4: args[3] = regs->regs[7];
+ case 3: args[2] = regs->regs[6];
+ case 2: args[1] = regs->regs[5];
+ case 1: args[0] = regs->regs[4];
+ break;
+ default:
+ BUG();
+ }
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ const unsigned long *args)
+{
+ /* Same note as above applies */
+ BUG_ON(i);
+
+ switch (n) {
+ case 6: regs->regs[1] = args[5];
+ case 5: regs->regs[0] = args[4];
+ case 4: regs->regs[7] = args[3];
+ case 3: regs->regs[6] = args[2];
+ case 2: regs->regs[5] = args[1];
+ case 1: regs->regs[4] = args[0];
+ break;
+ default:
+ BUG();
+ }
+}
+
+#endif /* __ASM_SH_SYSCALL_32_H */