source: trunk/hal/tsar_mips32/hal_do_syscall.c @ 35

/*
 * hal_do_syscall.c - implementation of syscall handler for TSAR-MIPS32
 * 
 * Author   Ghassan Almaless (2008,2009,2010,2011,2012)
 *
 * Copyright (c) UPMC Sorbonne Universites
 *
 * This file is part of ALMOS-MKH.
 *
 * ALMOS-MKH.is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.0 of the License.
 *
 * ALMOS-MKH.is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ALMOS-MKH.; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <errno.h>
#include <syscall.h>
#include <cpu.h>
#include <pmm.h>
#include <thread.h>
#include <task.h>
#include <interrupt.h>
#include <kdmsg.h>
#include <cpu-regs.h>

extern reg_t do_syscall( reg_t arg0,
                                     reg_t arg1,
                                     reg_t arg2,
                                     reg_t arg3,
                                     reg_t service_nr );

///////////////////////////
static void sys_sigreturn()
{
        register thread_t * this;
        register uint32_t   uzone_src;
 
        this = CURRENT_THREAD;
 
        uzone_src  = this->pws.sigstack_top;
        uzone_src -= sizeof(this->uzone);
  
        hal_copy_from_uspace( &this->uzone, 
                          (void*)uzone_src, 
                          sizeof(this->uzone) );

        if(err)
        {
                printk(WARNING, "WARNING: %s: CPU %d, Task %d, Thread %d (%x) [ KILLED ]\n", 
                       __FUNCTION__, 
                       hal_get_id(), 
                       this->task->pid, 
                       this->info.order,
                       this);

                sys_thread_exit((void*)EINTR);
        }

        if(current_cpu->fpu_owner == this)
        {
                current_cpu->fpu_owner = NULL;
                hal_fpu_disable();
        }

        thread_clear_signaled(this);

        this->uzone.regs[V0]   = this->info.retval;
        this->uzone.regs[V1]   = this->info.errno;
        this->uzone.regs[EPC] += 4;
}

/////////////////////////////////////////////
thread_t * hal_do_syscall( reg_t * regs_tbl )
{
        register reg_t      arg0;
        register reg_t      arg1;
        register reg_t      arg2;
        register reg_t      arg3;
        register reg_t      service_nr;
        register reg_t      retval;
        register thread_t * this;
  
        service_nr = regs_tbl[V0];

        if(service_nr == SYS_SIGRETURN)
        {
                sys_sigreturn();
                return CURRENT_THREAD;
        }

        arg0 = regs_tbl[A0];
        arg1 = regs_tbl[A1];
        arg2 = regs_tbl[A2];
        arg3 = regs_tbl[A3];
 
        retval = do_syscall( arg0 , arg1 , arg2 , arg3 , service_nr );

        this   = CURRENT_THREAD;
 
        this->uzone.regs[V0]   = retval;
        this->uzone.regs[V1]   = this->info.errno;
        this->uzone.regs[EPC] += 4;

        return this;
}