syscall_32.h

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#ifndef __ASM_SH_SYSCALL_32_H
#define __ASM_SH_SYSCALL_32_H

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/err.h>
#include <asm/ptrace.h>

/* The system call number is given by the user in R3 */
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 long syscall_get_error(struct task_struct *task,
                     struct pt_regs *regs)
{
    return IS_ERR_VALUE(regs->regs[0]) ? 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)
        regs->regs[0] = -error;
    else
        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];
    case 0:
        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 */