filesys.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.
 *
 *----------------------------------------------------------------------
 */

/*
 *	filesys.c (file)
 *
 *	File management
 *	File system connection/disconnection etc.
 */

#include "filesys.h"
#include "diskio.h"


LOCAL WER attachDevice( DevName dev, UW omode, PINFO *pinfo, DiskInfo *diskinfo, FsInfo **fs );
LOCAL ER detachDevice( ID diskid, FsInfo *fs );
LOCAL ER checkRootFileHeaderID( DfSystemHeader *sh, DiskMapInfo *dmInfo );
LOCAL void getFileSystemStatus( FS_STATE *fs, DfSystemHeader *sh, BOOL big );
LOCAL ER changeRootFileName( FileName fname, DfSystemHeader *sh, DiskMapInfo *dmInfo );
LOCAL ER changeFileSystemInfo( TC *fsnm, TC *dlnm, FsInfo *fs, DfSystemHeader *sh, DiskMapInfo *dmInfo, UW *mdflg );

#define TSD_FMC_CNT_M2	(-2)

/*
 * Select a file system by the device name.
 */
EXPORT FsInfo* fmSelectFileSystemOfDevName( DevName dev )
{
	QUEUE	*q;
	FsInfo	*fs;
	W	cmp;

	for ( q = fmInfo.fsLink.next; q != &fmInfo.fsLink; q = q->next ) {
		fs = (FsInfo*)q;
		cmp = tc_strncmp(dev, fs->devName, DevNameLen);
		if ( cmp == 0 ) {
			return fs;
		}
	}

	return (FsInfo*)NULL;
}

/*
 * Select a file system by the connection name.
 */
EXPORT FsInfo* fmSelectFileSystemOfConName( ConName con )
{
	QUEUE	*q;
	FsInfo	*fs;
	W	cmp;

	for ( q = fmInfo.fsLink.next; q != &fmInfo.fsLink; q = q->next ) {
		fs = (FsInfo*)q;
		cmp = tc_strncmp(con, fs->conName, ConNameLen);
		if ( cmp == 0 ) {
			return fs;
		}
	}

	return (FsInfo*)NULL;
}

/*
 * Select a file system by the file system name.
 */
EXPORT FsInfo* fmSelectFileSystemOfFsName( FsName fsnm )
{
	QUEUE	*q;
	FsInfo	*fs;
	W	cmp;

	for ( q = fmInfo.fsLink.next; q != &fmInfo.fsLink; q = q->next ) {
		fs = (FsInfo*)q;
		cmp = tc_strncmp(fsnm, fs->fsName, FsNameLen);
		if ( cmp == 0 ) {
			return fs;
		}
	}

	return (FsInfo*)NULL;
}

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

/*
 * att_fls: File system connection
 */
EXPORT void fmcAttachFileSystem( FmCmdPkt *pkt )
{
	FsInfo		*fs;
	T_CTSK		ctsk;
	ER		err;

	/* Reserve the memory for the file system management information. */
	fs = (FsInfo*)Kmalloc(sizeof(FsInfo));
	if ( fs == NULL ) {
		err = E_NOMEM;
		goto err_ret1;
	}
	memset(fs, 0, (size_t)sizeof(FsInfo));

	/* Create the lock for exclusive access. */
	err = CreateLock(&fs->lock, (UB*)"FSys");
	if ( err < E_OK ) {
		goto err_ret2;
	}

	/* Generate the rendezvous port for command forwarding. */
	SetOBJNAME(fmPortAttr.exinf, "FSys");
	err = tk_cre_por(&fmPortAttr);
	if ( err < E_OK ) {
		err = ERtoERR(err);
		goto err_ret3;
	}
	fs->port = (ID)err;

	/* Generate/Start the file system task. */
	SetFsTaskAttr(&ctsk, fs, fmInfo.fsTskPri);
	err = tk_cre_tsk(&ctsk);
	if ( err < E_OK ) {
		err = ERtoERR(err);
		goto err_ret4;
	}
	fs->tskid = (ID)err;

	err = tk_sta_tsk(fs->tskid, fs->port);
	if ( err < E_OK ) {
		err = ERtoERR(err);
		goto err_ret5;
	}

	/* Connection request to the file system task. */
	err = fmcCallFsTask(fs->port, pkt);
	if ( err < E_OK ) {
		goto err_ret6;
	}
	err = pkt->cmd.ret;
	if ( err < E_OK ) {
		goto err_ret6;
	}

	QueInsert(&fs->q, &fmInfo.fsLink);

	return;

	/*
	 * Error processing
	 */
err_ret6:
	(void)tk_ter_tsk(fs->tskid);
err_ret5:
	(void)tk_del_tsk(fs->tskid);
err_ret4:
	(void)tk_del_por(fs->port);
err_ret3:
	DeleteLock(&fs->lock);
err_ret2:
	Kfree((VB*)fs);
err_ret1:
	DEBUG_PRINT(("fmcAttchFileSystem err = %d\n", err));
	pkt->cmd.ret = err;
	return;
}

/*
 * det_fls: Disconnect the file system.
 */
EXPORT void fmcDetachFileSystem( FmCmdPkt *pkt )
{
	FM_DET_FLS_PARA	*cmdPara = (FM_DET_FLS_PARA*)pkt->cmd.para;
	FsInfo		*fs;
	ER		err;

	/* Select a file system. */
	err = CheckStrSpaceR(cmdPara->dev, DevNameLen);
	if ( err < E_OK ) {
		goto ret;
	}
	fs = fmSelectFileSystemOfDevName(cmdPara->dev);
	if ( fs == NULL ) {
		err = E_NOFS;
		goto ret;
	}

	/* Disconnection request to the file system task. */
	err = fmcCallFsTask(fs->port, pkt);
	if ( err < E_OK ) {
		goto ret;
	}
	err = pkt->cmd.ret;
	if ( err < E_OK ) {
		goto ret;
	}

	/*** Hereafter, the disconnection processing can not be stopped. ***/

	/* Delete the file system. */
	(void)fmcDeleteFileSystem(fs);

ret:
	pkt->cmd.ret = err;
	return;
}

/*
 * Delete the file system
 *	(Even if an error occurs halfway through the processing, it is not stopped.)
 */
EXPORT ER fmcDeleteFileSystem( FsInfo *fs )
{
	ER	err = E_OK;

	/* Stop/Delete the file system task. */
	err = tk_ter_tsk(fs->tskid);
	if ( err != E_OK ) {
		DEBUG_PRINT(("tk_ter_tsk er = %d\n", err));
		err = ERtoERR(err);
	}
	err = tk_del_tsk(fs->tskid);
	if ( err != E_OK ) {
		DEBUG_PRINT(("tk_del_tsk er = %d\n", err));
		err = ERtoERR(err);
	}

	/* Delete the rendezvous port for command forwarding */
	err = tk_del_por(fs->port);
	if ( err != E_OK ) {
		DEBUG_PRINT(("tk_del_por er = %d\n", err));
		err = ERtoERR(err);
	}

	/* Delete the lock for exclusive access. */
	DeleteLock(&fs->lock);

	/* Delete the memory for file system management information. */
	QueRemove(&fs->q);
	Kfree((VB*)fs);

	return err;
}

/*
 * syn_fls: Synchronize the file system.
 */
EXPORT void fmcSyncFileSystem( FmCmdPkt *pkt )
{
	QUEUE	*q;
	ER	err, error = E_OK;

	/* Synchronize all the file systems being connected in sequence. */
	for ( q = fmInfo.fsLink.next; q != &fmInfo.fsLink; q = q->next ) {

		err = SyncFS(((FsInfo*)q)->dskid, 0);
		if ( err < E_OK ) {
			error = err;
		}
	}

#ifdef DEBUG
	if ( error < E_OK ) {
		DEBUG_PRINT(("fmcSyncFileSystem err = %d\n", error));
	}
#endif

	pkt->cmd.ret = error;
	return;
}

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

/*
 * lst_fls: List the file systems.
 */
EXPORT void fmcListFileSystem( FmCmdPkt *pkt )
{
	FM_LST_FLS_PARA	*cmdPara = (FM_LST_FLS_PARA*)pkt->cmd.para;
	W		cnt  = cmdPara->cnt;
	F_ATTACH	*buf = cmdPara->buff;
	W		nfs;	/* The number of connected file systems */
	FsInfo		*fs;
	ER		err;

	/* Parameter check */
	if ( (cnt == 0) || (cnt < TSD_FMC_CNT_M2) ) {
		err = E_PAR;
		goto err_ret;
	}
	if ( cnt < 0 ) {
		cnt = 1;
	}
	err = CheckSpaceRW(buf, (W)(sizeof(F_ATTACH)*(UW)cnt));
	if ( err != E_OK ) {
		goto err_ret;
	}

	if ( cmdPara->cnt > 0 ) {
		QUEUE	*q;

		/* Listing */
		nfs = 0;
		for ( q = fmInfo.fsLink.next;
				q != &fmInfo.fsLink; q = q->next ) {

			if ( ++nfs > cnt ) {
				continue;
			}

			fs = (FsInfo*)q;
			tc_strncpy(buf->a_name, fs->conName, ConNameLen);
			tc_strncpy(buf->dev,    fs->devName, DevNameLen);
			buf++;
		}
	} else {
		if ( cmdPara->cnt == F_GETDEV ) {
			/* Obtain the device name. (F_GETDEV) */
			fs = fmSelectFileSystemOfConName(buf->a_name);
			if ( fs == NULL ) {
				err = E_NOFS;
				goto err_ret;
			}
			tc_strncpy(buf->dev, fs->devName, DevNameLen);
		} else {
			/* Obtain the connection name. (F_GETNAM) */
			fs = fmSelectFileSystemOfDevName(buf->dev);
			if ( fs == NULL ) {
				err = E_NOFS;
				goto err_ret;
			}
			tc_strncpy(buf->a_name, fs->conName, ConNameLen);
		}
		nfs = 1;
	}

	pkt->cmd.ret = nfs;
	return;

err_ret:
	DEBUG_PRINT(("fmcListFileSystem err = %d\n", err));
	pkt->cmd.ret = err;
	return;
}

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

/*
 * Connect the disk device.
 *	When already connected, perform only the check of access right,
 *	and lock the file system task.
 */
LOCAL WER attachDevice( DevName dev, UW omode, PINFO *pinfo,
					DiskInfo *diskinfo, FsInfo **fs )
{
	ID	diskid;
	ER	err;

	/* Whether the device of the same name is connected. */
	*fs = fmSelectFileSystemOfDevName(dev);
	if ( *fs == NULL ) {
		/* Not connected yet: Make new connection. */
		err = AttachFS(dev, omode, pinfo, diskinfo);
		if ( err < E_OK ) {
			goto err_ret1;
		}
		diskid = (ID)err;

		/* Check the disk partition information. */
		err = fmCheckPartitionID(dev);
		if ( err < E_OK ) {
			goto err_ret2;
		}
	} else {