port.c

T-kernel 的extension源代码

/*
 *----------------------------------------------------------------------
 *    T-Kernel / Standard Extension
 *
 *    Copyright (C) 2006 by Ken Sakamura. All rights reserved.
 *    T-Kernel / Standard Extension is distributed 
 *      under the T-License for T-Kernel / Standard Extension.
 *----------------------------------------------------------------------
 *
 *    Version:   1.00.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2006/8/11.
 *
 *----------------------------------------------------------------------
 */

/*
 *	port.c (file)
 *
 *	File management
 *	Sending and forwarding, etc. of commands by the rendezvous port
 */

#include "fminfo.h"
#include "filesys.h"


LOCAL	ER	fmpEnterSyncExec( void );
LOCAL	ER	fmpExitSyncExec( void );
LOCAL	ER	fmpCallMgrTask( FmCmdPkt *pkt, SyscallPattern ptn );

/* ------------------------------------------------------------------------ */
/*
 *	When calling other file system task from one file system task synchronously, if the tasks
 *	call each other simultaneously,a deadlock occurs. In order to avoid the problem, we have
 *	prepared the synchronous execution flag to perform control so that only one synchronous
 *	call can be executed at a time. Overlapped synchronous executions result in EFM_RETRY
 *	error and reexecution is reserved. (See fstask.c:fmpFsTask() )
 */

/*
 * Start the synchronous execution.
 */
LOCAL ER fmpEnterSyncExec( void )
{
	ER	err;

#ifdef DEBUG
	if ( GetFsInfo(TSK_SELF) == NULL ) {
		err = E_SYS;
		goto err_ret;
	}
#endif

	err = tk_wai_sem(fmInfo.syncExecFlag, 1, SyncExecWait);
	if ( err != E_OK ) {
		err = ( err == E_TMOUT )? EFM_RETRY: ERtoERR(err);
		goto err_ret;
	}
	return E_OK;

err_ret:
	DEBUG_PRINT(("fmpEnterSyncExec err = %d\n", err));
	return err;
}

/*
 * End the synchronous execution.
 */
LOCAL ER fmpExitSyncExec( void )
{
	ER	err;

	err = tk_sig_sem(fmInfo.syncExecFlag, 1);
	if ( err != E_OK ) {
		DEBUG_PRINT(("fmpExitSyncExec er = %d\n", err));
		return ERtoERR(err);
	}
	return E_OK;
}

/* ------------------------------------------------------------------------ */

/*
 * Call the file management common section.
 *	(For call from the extended SVC section)
 */
EXPORT ER fmCallMgrTask( FmCmdPkt *pkt, SyscallPattern ptn )
{
	INT	rmsgsz;

	rmsgsz = tk_cal_por(fmInfo.entryPort, ptn, &pkt, (W)sizeof(VP), TMO_FEVR);
	if ( rmsgsz < E_OK ) {
		DEBUG_PRINT(("fmCallMgrTask er = %d\n", rmsgsz));
		return ERtoERR(rmsgsz);
	}

	return E_OK;
}

/*
 * Call the file management common section.
 *	(For call from the file system task)
 */
LOCAL ER fmpCallMgrTask( FmCmdPkt *pkt, SyscallPattern ptn )
{
	INT	rmsgsz;
	ER	err;

	/* Start the synchronous execution */
	err = fmpEnterSyncExec();
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Call the file management common section. */
	rmsgsz = tk_cal_por(fmInfo.entryPort, ptn, &pkt, (W)sizeof(VP), TMO_FEVR);

	/* End the synchronous execution. */
	err = fmpExitSyncExec();
	if ( err < E_OK ) {
		goto err_ret;
	}

	if ( rmsgsz < E_OK ) {
		err = ERtoERR(rmsgsz);
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("fmpCallMgrTask err = %d\n", err));
	return err;
}

/*
 * Forward to the file management common section.
 */
EXPORT ER fmForwardMgrTask( RNO rdvno, FmCmdPkt *pkt )
{
	ER	err;

	err = tk_fwd_por(fmInfo.entryPort, Syscall_OWN, rdvno,
					&pkt, sizeof(VP));
	if ( err != E_OK ) {
		DEBUG_PRINT(("fmForwardMgrTask er = %d\n", err));
		return ERtoERR(err);
	}

	return E_OK;
}

/*
 * Call the file system section.
 *	(It can be called only from the manager task.)
 */
EXPORT ER fmcCallFsTask( ID port, FmCmdPkt *pkt )
{
	INT	rmsgsz;

	Unlock(&fmInfo.lock);
	rmsgsz = tk_cal_por(port, Syscall_OWN, &pkt, sizeof(VP), TMO_FEVR);
	Lock(&fmInfo.lock);
	if ( rmsgsz < E_OK ) {
		DEBUG_PRINT(("fmCallFsTask er = %d\n", rmsgsz));
		return ERtoERR(rmsgsz);
	}

	return E_OK;
}

/*
 * Forward to the file system section.
 */
EXPORT ER fmForwardFsTask( ID port, RNO rdvno, FmCmdPkt *pkt )
{
	ER	err;

	err = tk_fwd_por(port, Syscall_OWN, rdvno, &pkt, sizeof(VP));
	if ( err != E_OK ) {
		DEBUG_PRINT(("fmForwardFsTask er = %d\n", err));
		return ERtoERR(err);
	}

	return E_OK;
}

/* ======================================================================== */
/*
 *	Service command between file systems for internal use
 *	Entry for call
 */

/*
 * Obtain the file information.
 *	(It can be called only from the file system task.)
 */
EXPORT ER fmIGetFileInfo( LINK *lnk, FileName fname,
				STIME *ctime, FileAccMode *amode )
{
	FMI_GetFileInfo_PARA	para;
	FmCmdPkt	pkt = NIL;
	ER		err;

	/* Set the packet. */
	pkt.cmd.fno.w = FMI_GetFileInfo_FN;
	pkt.cmd.para  = &para;
	para.lnk   = lnk;
	para.fname = fname;
	para.ctime = ctime;
	para.amode = amode;

	/* Call the rendezvous. */
	err = fmpCallMgrTask(&pkt, Syscall_OWN);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return pkt.cmd.ret;

err_ret:
	DEBUG_PRINT(("fmIGetFileInfo err = %d\n", err));
	return err;
}

/*
 * Change the link file name.
 *	(It can be called only from the file system task.)
 */
EXPORT ER fmIChangeLinkFileName( LINK *lnk, FileName fname )
{
	FMI_ChangeLinkFileName_PARA	para;
	FmCmdPkt	pkt = NIL;
	ER		err;

	/* Set the packet. */
	pkt.cmd.fno.w = FMI_ChangeLinkFileName_FN;
	pkt.cmd.para  = &para;
	para.lnk   = lnk;
	para.fname = fname;

	/* Call the rendezvous. */
	err = fmpCallMgrTask(&pkt, Syscall_OWN);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return pkt.cmd.ret;

err_ret:
	DEBUG_PRINT(("fmIChangeLinkFileName err = %d\n", err));
	return err;
}

/*
 * Set the work file. (at startup)
 */
EXPORT ER fmISetWorkFile( LINK *lnk, PINFO *pinfo )
{
	FMI_SetWorkFile_PARA	para;
	FmCmdPkt	pkt = NIL;
	ER		err;

	/* Set the packet */
	pkt.cmd.fno.w = FMI_SetWorkFile_FN;
	pkt.cmd.para  = &para;
	para.lnk   = lnk;
	para.pinfo = pinfo;

	/* Call the rendezvous. */
	err = fmCallMgrTask(&pkt, Syscall_OWN);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return pkt.cmd.ret;

err_ret:
	DEBUG_PRINT(("fmISetWorkFile err = %d\n", err));
	return err;
}

/*
 * File close (at internal call of cls_fil/cleanup)
 *	(It can be called only from the manager task.)
 */
EXPORT ER fmcICloseFile( FD *fd )
{
	FM_CLS_FIL_PARA	para;
	FmCmdPkt	pkt = NIL;
	FsInfo		*fs;
	ER		err;

	fs = fd->fs;
	if ( fs == NULL ) {
		err = E_FD;
		goto err_ret;
	}

	/* Set the packet. */
	pkt.cmd.fno.w = FM_CLS_FIL_FN;
	pkt.cmd.para  = &para;
	pkt.wrk.pinfo = fd->pinfo;
	para.fd = getFDno(fd);

	/* Call the rendezvous. */
	err = fmcCallFsTask(fs->port, &pkt);
	if ( err < E_OK ) {
		goto err_ret;
	}

	return pkt.cmd.ret;

err_ret:
	DEBUG_PRINT(("fmcICloseFile err = %d\n", err));
	return err;
}