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-rw-r--r--arch/mips/include/asm/syscall.h160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h
new file mode 100644
index 0000000000..ebdf4d910a
--- /dev/null
+++ b/arch/mips/include/asm/syscall.h
@@ -0,0 +1,160 @@
+/*
+ * Access to user system call parameters and results
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * See asm-generic/syscall.h for descriptions of what we must do here.
+ *
+ * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org>
+ */
+
+#ifndef __ASM_MIPS_SYSCALL_H
+#define __ASM_MIPS_SYSCALL_H
+
+#include <linux/compiler.h>
+#include <uapi/linux/audit.h>
+#include <linux/elf-em.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <asm/ptrace.h>
+#include <asm/unistd.h>
+
+#ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */
+#define __NR_syscall 4000
+#endif
+
+static inline bool mips_syscall_is_indirect(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
+ return (IS_ENABLED(CONFIG_32BIT) ||
+ test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
+ (regs->regs[2] == __NR_syscall);
+}
+
+static inline long syscall_get_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return task_thread_info(task)->syscall;
+}
+
+static inline void mips_syscall_update_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /*
+ * v0 is the system call number, except for O32 ABI syscall(), where it
+ * ends up in a0.
+ */
+ if (mips_syscall_is_indirect(task, regs))
+ task_thread_info(task)->syscall = regs->regs[4];
+ else
+ task_thread_info(task)->syscall = regs->regs[2];
+}
+
+static inline void mips_get_syscall_arg(unsigned long *arg,
+ struct task_struct *task, struct pt_regs *regs, unsigned int n)
+{
+ unsigned long usp __maybe_unused = regs->regs[29];
+
+ switch (n) {
+ case 0: case 1: case 2: case 3:
+ *arg = regs->regs[4 + n];
+
+ return;
+
+#ifdef CONFIG_32BIT
+ case 4: case 5: case 6: case 7:
+ get_user(*arg, (int *)usp + n);
+ return;
+#endif
+
+#ifdef CONFIG_64BIT
+ case 4: case 5: case 6: case 7:
+#ifdef CONFIG_MIPS32_O32
+ if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
+ get_user(*arg, (int *)usp + n);
+ else
+#endif
+ *arg = regs->regs[4 + n];
+
+ return;
+#endif
+
+ default:
+ BUG();
+ }
+
+ unreachable();
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->regs[7] ? -regs->regs[2] : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->regs[2];
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ /* Do nothing */
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+ struct pt_regs *regs,
+ int error, long val)
+{
+ if (error) {
+ regs->regs[2] = -error;
+ regs->regs[7] = 1;
+ } else {
+ regs->regs[2] = val;
+ regs->regs[7] = 0;
+ }
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned long *args)
+{
+ unsigned int i = 0;
+ unsigned int n = 6;
+
+ /* O32 ABI syscall() */
+ if (mips_syscall_is_indirect(task, regs))
+ i++;
+
+ while (n--)
+ mips_get_syscall_arg(args++, task, regs, i++);
+}
+
+extern const unsigned long sys_call_table[];
+extern const unsigned long sys32_call_table[];
+extern const unsigned long sysn32_call_table[];
+
+static inline int syscall_get_arch(struct task_struct *task)
+{
+ int arch = AUDIT_ARCH_MIPS;
+#ifdef CONFIG_64BIT
+ if (!test_tsk_thread_flag(task, TIF_32BIT_REGS)) {
+ arch |= __AUDIT_ARCH_64BIT;
+ /* N32 sets only TIF_32BIT_ADDR */
+ if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
+ arch |= __AUDIT_ARCH_CONVENTION_MIPS64_N32;
+ }
+#endif
+#if defined(__LITTLE_ENDIAN)
+ arch |= __AUDIT_ARCH_LE;
+#endif
+ return arch;
+}
+
+#endif /* __ASM_MIPS_SYSCALL_H */