arch/sh/include/asm/syscall_32.h

   1 #ifndef __ASM_SH_SYSCALL_32_H
   2 #define __ASM_SH_SYSCALL_32_H
   3
   4 #include <linux/kernel.h>
   5 #include <linux/sched.h>
   6 #include <linux/err.h>
   7 #include <asm/ptrace.h>
   8
   9 /* The system call number is given by the user in R3 */
  10 static inline long syscall_get_nr(struct task_struct *task,
  11                                   struct pt_regs *regs)
  12 {
  13         return (regs->tra >= 0) ? regs->regs[3] : -1L;
  14 }
  15
  16 static inline void syscall_rollback(struct task_struct *task,
  17                                     struct pt_regs *regs)
  18 {
  19         /*
  20          * XXX: This needs some thought. On SH we don't
  21          * save away the original r0 value anywhere.
  22          */
  23 }
  24
  25 static inline long syscall_get_error(struct task_struct *task,
  26                                      struct pt_regs *regs)
  27 {
  28         return IS_ERR_VALUE(regs->regs[0]) ? regs->regs[0] : 0;
  29 }
  30
  31 static inline long syscall_get_return_value(struct task_struct *task,
  32                                             struct pt_regs *regs)
  33 {
  34         return regs->regs[0];
  35 }
  36
  37 static inline void syscall_set_return_value(struct task_struct *task,
  38                                             struct pt_regs *regs,
  39                                             int error, long val)
  40 {
  41         if (error)
  42                 regs->regs[0] = -error;
  43         else
  44                 regs->regs[0] = val;
  45 }
  46
  47 static inline void syscall_get_arguments(struct task_struct *task,
  48                                          struct pt_regs *regs,
  49                                          unsigned int i, unsigned int n,
  50                                          unsigned long *args)
  51 {
  52         /*
  53          * Do this simply for now. If we need to start supporting
  54          * fetching arguments from arbitrary indices, this will need some
  55          * extra logic. Presently there are no in-tree users that depend
  56          * on this behaviour.
  57          */
  58         BUG_ON(i);
  59
  60         /* Argument pattern is: R4, R5, R6, R7, R0, R1 */
  61         switch (n) {
  62         case 6: args[5] = regs->regs[1];
  63         case 5: args[4] = regs->regs[0];
  64         case 4: args[3] = regs->regs[7];
  65         case 3: args[2] = regs->regs[6];
  66         case 2: args[1] = regs->regs[5];
  67         case 1: args[0] = regs->regs[4];
  68         case 0:
  69                 break;
  70         default:
  71                 BUG();
  72         }
  73 }
  74
  75 static inline void syscall_set_arguments(struct task_struct *task,
  76                                          struct pt_regs *regs,
  77                                          unsigned int i, unsigned int n,
  78                                          const unsigned long *args)
  79 {
  80         /* Same note as above applies */
  81         BUG_ON(i);
  82
  83         switch (n) {
  84         case 6: regs->regs[1] = args[5];
  85         case 5: regs->regs[0] = args[4];
  86         case 4: regs->regs[7] = args[3];
  87         case 3: regs->regs[6] = args[2];
  88         case 2: regs->regs[5] = args[1];
  89         case 1: regs->regs[4] = args[0];
  90                 break;
  91         default:
  92                 BUG();
  93         }
  94 }
  95
  96 #endif /* __ASM_SH_SYSCALL_32_H */