1 files changed, 34 insertions, 7 deletions

diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h
index fc556d8052c9..c6e9cd2bca8d 100644
--- a/arch/mips/include/asm/syscall.h
+++ b/arch/mips/include/asm/syscall.h
@@ -13,23 +13,35 @@
 #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 long syscall_get_nr(struct task_struct *task,
                                   struct pt_regs *regs)
 {
-        return regs->regs[2];
+        /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
+        if ((config_enabled(CONFIG_32BIT) ||
+            test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
+            (regs->regs[2] == __NR_syscall))
+                return regs->regs[4];
+        else
+                return regs->regs[2];
 }
 
 static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
         struct task_struct *task, struct pt_regs *regs, unsigned int n)
 {
-        unsigned long usp = regs->regs[29];
+        unsigned long usp __maybe_unused = regs->regs[29];
 
         switch (n) {
         case 0: case 1: case 2: case 3:
@@ -39,14 +51,14 @@ static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
 
 #ifdef CONFIG_32BIT
         case 4: case 5: case 6: case 7:
-                return get_user(*arg, (int *)usp + 4 * n);
+                return get_user(*arg, (int *)usp + n);
 #endif
 
 #ifdef CONFIG_64BIT
         case 4: case 5: case 6: case 7:
 #ifdef CONFIG_MIPS32_O32
                 if (test_thread_flag(TIF_32BIT_REGS))
-                        return get_user(*arg, (int *)usp + 4 * n);
+                        return get_user(*arg, (int *)usp + n);
                 else
 #endif
                         *arg = regs->regs[4 + n];
@@ -57,6 +69,8 @@ static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
         default:
                 BUG();
         }
+
+        unreachable();
 }
 
 static inline long syscall_get_return_value(struct task_struct *task,
@@ -65,6 +79,12 @@ static inline long syscall_get_return_value(struct task_struct *task,
         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)
@@ -83,11 +103,17 @@ static inline void syscall_get_arguments(struct task_struct *task,
                                          unsigned int i, unsigned int n,
                                          unsigned long *args)
 {
-        unsigned long arg;
         int ret;
+        /* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
+        if ((config_enabled(CONFIG_32BIT) ||
+            test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
+            (regs->regs[2] == __NR_syscall)) {
+                i++;
+                n++;
+        }
 
         while (n--)
-                ret |= mips_get_syscall_arg(&arg, task, regs, i++);
+                ret |= mips_get_syscall_arg(args++, task, regs, i++);
 
         /*
          * No way to communicate an error because this is a void function.
@@ -105,7 +131,8 @@ static inline int syscall_get_arch(void)
 {
         int arch = EM_MIPS;
 #ifdef CONFIG_64BIT
-        arch |=  __AUDIT_ARCH_64BIT;
+        if (!test_thread_flag(TIF_32BIT_REGS))
+                arch |= __AUDIT_ARCH_64BIT;
 #endif
 #if defined(__LITTLE_ENDIAN)
         arch |=  __AUDIT_ARCH_LE;