source: trunk/kernel/syscalls/sys_barrier.c @ 11

/*
 * kern/sys_barrier.c - barrier service interface for userland
 * 
 * Copyright (c) 2008,2009,2010,2011,2012 Ghassan Almaless
 * Copyright (c) 2011,2012 UPMC Sorbonne Universites
 *
 * This file is part of ALMOS-kernel.
 *
 * ALMOS-kernel 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-kernel 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-kernel; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <types.h>
#include <errno.h>
#include <thread.h>
#include <task.h>
#include <kmem.h>
#include <vmm.h>
#include <kmagics.h>
#include <barrier.h>

int sys_barrier(struct barrier_s **barrier, uint_t operation, uint_t count)
{
        kmem_req_t req;
        struct barrier_s *ibarrier;
        error_t err = EINVAL;
  
        if((err = vmm_check_address("usr barrier ptr", 
                                    current_task, 
                                    barrier,
                                    sizeof(struct barrier_s*))))
                goto SYS_BARRIER_END;

        if((err = cpu_copy_from_uspace(&ibarrier, barrier, sizeof(struct barrier_s *))))
                goto SYS_BARRIER_END;

        switch(operation)
        {
        case BARRIER_INIT_PRIVATE:
        case BARRIER_INIT_SHARED:
                req.type  = KMEM_BARRIER;
                req.size  = sizeof(*ibarrier);
                req.flags = AF_USER;

                if((ibarrier = kmem_alloc(&req)) == NULL)
                {
                        err = ENOMEM;
                        break;
                }
    
                if((err = barrier_init(ibarrier, count, operation)))
                        break;
    
                if((err = cpu_copy_to_uspace(barrier, &ibarrier, sizeof(struct barrier_s *))))
                {
                        req.ptr = ibarrier;
                        kmem_free(&req);
                }
                break;

        case BARRIER_WAIT:

                if((err = vmm_check_object(ibarrier, struct barrier_s, BARRIER_ID)))
                        break;

                err = barrier_wait(ibarrier);
                break;

        case BARRIER_DESTROY:
    
                if((err = vmm_check_object(ibarrier, struct barrier_s, BARRIER_ID)))
                        break;
    
                if((err = barrier_destroy(ibarrier)))
                        break;
   
                req.type = KMEM_BARRIER;
                req.ptr  = ibarrier;
                kmem_free(&req);
                return 0;

        default:
                err = EINVAL;
        }

SYS_BARRIER_END:
        current_thread->info.errno = err;
        return err;
}

KMEM_OBJATTR_INIT(barrier_kmem_init)
{
        attr->type   = KMEM_BARRIER;
        attr->name   = "KCM Barrier";
        attr->size   = sizeof(struct barrier_s);
        attr->aligne = 0;
        attr->min    = CONFIG_BARRIER_MIN;
        attr->max    = CONFIG_BARRIER_MAX;
        attr->ctor   = NULL;
        attr->dtor   = NULL;
        return 0;
}