/*
 * vseg.c - virtual segment (vseg) related operations
 *
 * Authors   Alain Greiner (2016,2017,2018,2019)
 *
 * 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 <hal_kernel_types.h>
#include <hal_special.h>
#include <hal_remote.h>
#include <list.h>
#include <errno.h>
#include <printk.h>
#include <bits.h>
#include <thread.h>
#include <process.h>
#include <ppm.h>
#include <mapper.h>
#include <vfs.h>
#include <page.h>
#include <vmm.h>
#include <kmem.h>
#include <vseg.h>

////////////////////////////////////////////////////////////////////////////////////////
//   global variables for display / must be consistent with enum in "vseg.h"
////////////////////////////////////////////////////////////////////////////////////////


//////////////////////////////////////////
char * vseg_type_str( uint32_t vseg_type )
{
  	if     ( vseg_type == VSEG_TYPE_CODE   ) return "CODE";
  	else if( vseg_type == VSEG_TYPE_DATA   ) return "DATA";
  	else if( vseg_type == VSEG_TYPE_STACK  ) return "STAK";
  	else if( vseg_type == VSEG_TYPE_ANON   ) return "ANON";
  	else if( vseg_type == VSEG_TYPE_FILE   ) return "FILE";
  	else if( vseg_type == VSEG_TYPE_REMOTE ) return "REMO";
  	else if( vseg_type == VSEG_TYPE_KCODE  ) return "KCOD";
  	else if( vseg_type == VSEG_TYPE_KDATA  ) return "KDAT";
  	else if( vseg_type == VSEG_TYPE_KDEV   ) return "KDEV";
    else                                     return "undefined";
}

///////////////////////////
vseg_t * vseg_alloc( void )
{
    kmem_req_t   req;

    req.type  = KMEM_KCM;
	req.order = bits_log2( sizeof(vseg_t) );
	req.flags = AF_KERNEL | AF_ZERO;

    return kmem_alloc( &req );
}

///////////////////////////////
void vseg_free( vseg_t * vseg )
{
    kmem_req_t  req;

	req.type = KMEM_KCM;
	req.ptr  = vseg;
	kmem_free( &req );
}

///////////////////////////////////
void vseg_init( vseg_t      * vseg,
                vseg_type_t   type,
	            intptr_t      base,
                uint32_t      size,
                vpn_t         vpn_base,
                vpn_t         vpn_size,
		        uint32_t      file_offset,
                uint32_t      file_size,
                xptr_t        mapper_xp,
                cxy_t         cxy )
{
    vseg->type        = type;
	vseg->min         = base;
	vseg->max         = base + size;
    vseg->vpn_base    = vpn_base;
	vseg->vpn_size    = vpn_size;
    vseg->file_offset = file_offset;
    vseg->file_size   = file_size;
	vseg->mapper_xp   = mapper_xp;
    vseg->cxy         = cxy;

    // set vseg flags depending on type
	if     ( type == VSEG_TYPE_CODE )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_EXEC    |
                      VSEG_CACHE   |
                      VSEG_PRIVATE ;
    }
    else if( type == VSEG_TYPE_STACK )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_WRITE   |
                      VSEG_CACHE   |
                      VSEG_PRIVATE ;
    }
    else if( type == VSEG_TYPE_DATA )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_WRITE   |
                      VSEG_CACHE   |
                      VSEG_DISTRIB ;
    }
    else if( type == VSEG_TYPE_REMOTE )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_WRITE   |
                      VSEG_CACHE   ;
    }
    else if( type == VSEG_TYPE_ANON )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_WRITE   |
                      VSEG_CACHE; 
    }
    else if( type == VSEG_TYPE_FILE )
    {
        vseg->flags = VSEG_USER    |
                      VSEG_WRITE   |
                      VSEG_CACHE   ;
    }
    else if( type == VSEG_TYPE_KCODE )
    {
        vseg->flags = VSEG_EXEC    |
                      VSEG_CACHE   |
                      VSEG_PRIVATE ;
    }
    else if( type == VSEG_TYPE_KDATA )
    {
        vseg->flags = VSEG_CACHE   |
                      VSEG_WRITE   ;
    }
    else if( type == VSEG_TYPE_KDEV )
    {
        vseg->flags = VSEG_WRITE   ;
    }
    else
    {
	    assert( false , "illegal vseg type\n" );
    }

}  // end vseg_init()

//////////////////////////////////////////
void vseg_init_from_ref( vseg_t    * vseg,
                         xptr_t      ref_xp )
{
    // get remote vseg cluster and pointer
    cxy_t    cxy = (cxy_t   )GET_CXY( ref_xp );
    vseg_t * ptr = (vseg_t *)GET_PTR( ref_xp );

    // initialize vseg with remote_read access
    vseg->type        =           hal_remote_l32( XPTR( cxy , &ptr->type        ) );
    vseg->min         = (intptr_t)hal_remote_lpt( XPTR( cxy , &ptr->min         ) );
    vseg->max         = (intptr_t)hal_remote_lpt( XPTR( cxy , &ptr->max         ) );
    vseg->vpn_base    =           hal_remote_l32( XPTR( cxy , &ptr->vpn_base    ) );
    vseg->vpn_size    =           hal_remote_l32( XPTR( cxy , &ptr->vpn_size    ) );
    vseg->flags       =           hal_remote_l32( XPTR( cxy , &ptr->flags       ) );
    vseg->file_offset =           hal_remote_l32( XPTR( cxy , &ptr->file_offset ) );
    vseg->file_size   =           hal_remote_l32( XPTR( cxy , &ptr->file_size   ) );
	vseg->mapper_xp   = (xptr_t)  hal_remote_l64( XPTR( cxy , &ptr->mapper_xp   ) );

    switch (vseg->type)
    {
        case VSEG_TYPE_DATA:      // unused 
        {
            vseg->cxy = 0xffff;
            break;
        }
        case VSEG_TYPE_CODE:      // always local
        case VSEG_TYPE_STACK: 
        case VSEG_TYPE_KCODE:
        {
            vseg->cxy = local_cxy;
            break;
        }
        case VSEG_TYPE_ANON:      // intrinsic
        case VSEG_TYPE_FILE:
        case VSEG_TYPE_REMOTE: 
        case VSEG_TYPE_KDEV:
        case VSEG_TYPE_KDATA:
        {
            vseg->cxy = (cxy_t) hal_remote_l32( XPTR(cxy, &ptr->cxy) );
            break;
        }
        default: 
        {
            assert( false, "Illegal vseg type" );
            break;
        }
    }
}