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-rw-r--r--arch/metag/include/asm/syscall.h104
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/metag/include/asm/syscall.h b/arch/metag/include/asm/syscall.h
new file mode 100644
index 00000000000..24fc97939f7
--- /dev/null
+++ b/arch/metag/include/asm/syscall.h
@@ -0,0 +1,104 @@
+/*
+ * Access to user system call parameters and results
+ *
+ * Copyright (C) 2008 Imagination Technologies Ltd.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * See asm-generic/syscall.h for descriptions of what we must do here.
+ */
+
+#ifndef _ASM_METAG_SYSCALL_H
+#define _ASM_METAG_SYSCALL_H
+
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/uaccess.h>
+
+#include <asm/switch.h>
+
+static inline long syscall_get_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ unsigned long insn;
+
+ /*
+ * FIXME there's no way to find out how we got here other than to
+ * examine the memory at the PC to see if it is a syscall
+ * SWITCH instruction.
+ */
+ if (get_user(insn, (unsigned long *)(regs->ctx.CurrPC - 4)))
+ return -1;
+
+ if (insn == __METAG_SW_ENCODING(SYS))
+ return regs->ctx.DX[0].U1;
+ else
+ return -1L;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /* do nothing */
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ unsigned long error = regs->ctx.DX[0].U0;
+ return IS_ERR_VALUE(error) ? error : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->ctx.DX[0].U0;
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+ struct pt_regs *regs,
+ int error, long val)
+{
+ regs->ctx.DX[0].U0 = (long) error ?: val;
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ unsigned long *args)
+{
+ unsigned int reg, j;
+ BUG_ON(i + n > 6);
+
+ for (j = i, reg = 6 - i; j < (i + n); j++, reg--) {
+ if (reg % 2)
+ args[j] = regs->ctx.DX[(reg + 1) / 2].U0;
+ else
+ args[j] = regs->ctx.DX[reg / 2].U1;
+ }
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ const unsigned long *args)
+{
+ unsigned int reg;
+ BUG_ON(i + n > 6);
+
+ for (reg = 6 - i; i < (i + n); i++, reg--) {
+ if (reg % 2)
+ regs->ctx.DX[(reg + 1) / 2].U0 = args[i];
+ else
+ regs->ctx.DX[reg / 2].U1 = args[i];
+ }
+}
+
+#define NR_syscalls __NR_syscalls
+
+/* generic syscall table */
+extern const void *sys_call_table[];
+
+#endif /* _ASM_METAG_SYSCALL_H */