Commit a336ca6f authored by Tejun Heo's avatar Tejun Heo Committed by Jens Axboe
Browse files

ataflop: dequeue and track in-flight request 



ataflop has single request in flight.  Till now, whenever it needs to
access the in-flight request it called elv_next_request().  This patch
makes ataflop track the in-flight request directly and dequeue it when
processing starts.  The added complexity is minimal and this will help
future block layer changes.

[ Impact: dequeue in-flight request, one elv_next_request() per request ]

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 8a12c4a4

drivers/block/ataflop.c

+35 −28
Original line number Diff line number Diff line
@@ -79,9 +79,7 @@ 
#undef DEBUG



static struct request_queue *floppy_queue;



#define QUEUE (floppy_queue)

#define CURRENT elv_next_request(floppy_queue)

static struct request *fd_request;



/* Disk types: DD, HD, ED */

static struct atari_disk_type {
@@ -376,6 +374,12 @@ static DEFINE_TIMER(readtrack_timer, fd_readtrack_check, 0, 0); 
static DEFINE_TIMER(timeout_timer, fd_times_out, 0, 0);

static DEFINE_TIMER(fd_timer, check_change, 0, 0);

	

static void fd_end_request_cur(int err)

{

	if (!__blk_end_request_cur(fd_request, err))

		fd_request = NULL;

}



static inline void start_motor_off_timer(void)

{

	mod_timer(&motor_off_timer, jiffies + FD_MOTOR_OFF_DELAY);
@@ -606,15 +610,15 @@ static void fd_error( void ) 
		return;

	}



	if (!CURRENT)

	if (!fd_request)

		return;



	CURRENT->errors++;

	if (CURRENT->errors >= MAX_ERRORS) {

	fd_request->errors++;

	if (fd_request->errors >= MAX_ERRORS) {

		printk(KERN_ERR "fd%d: too many errors.\n", SelectedDrive );

		__blk_end_request_cur(CURRENT, -EIO);

		fd_end_request_cur(-EIO);

	}

	else if (CURRENT->errors == RECALIBRATE_ERRORS) {

	else if (fd_request->errors == RECALIBRATE_ERRORS) {

		printk(KERN_WARNING "fd%d: recalibrating\n", SelectedDrive );

		if (SelectedDrive != -1)

			SUD.track = -1;
@@ -725,14 +729,14 @@ static void do_fd_action( int drive ) 
	    if (IS_BUFFERED( drive, ReqSide, ReqTrack )) {

		if (ReqCmd == READ) {

		    copy_buffer( SECTOR_BUFFER(ReqSector), ReqData );

		    if (++ReqCnt < blk_rq_cur_sectors(CURRENT)) {

		    if (++ReqCnt < blk_rq_cur_sectors(fd_request)) {

			/* read next sector */

			setup_req_params( drive );

			goto repeat;

		    }

		    else {

			/* all sectors finished */

			__blk_end_request_cur(CURRENT, 0);

			fd_end_request_cur(0);

			redo_fd_request();

			return;

		    }
@@ -1130,14 +1134,14 @@ static void fd_rwsec_done1(int status) 
		}

	}

  

	if (++ReqCnt < blk_rq_cur_sectors(CURRENT)) {

	if (++ReqCnt < blk_rq_cur_sectors(fd_request)) {

		/* read next sector */

		setup_req_params( SelectedDrive );

		do_fd_action( SelectedDrive );

	}

	else {

		/* all sectors finished */

		__blk_end_request_cur(CURRENT, 0);

		fd_end_request_cur(0);

		redo_fd_request();

	}

	return;
@@ -1378,7 +1382,7 @@ static void setup_req_params( int drive ) 
	ReqData = ReqBuffer + 512 * ReqCnt;



	if (UseTrackbuffer)

		read_track = (ReqCmd == READ && CURRENT->errors == 0);

		read_track = (ReqCmd == READ && fd_request->errors == 0);

	else

		read_track = 0;
@@ -1392,25 +1396,28 @@ static void redo_fd_request(void) 
	int drive, type;

	struct atari_floppy_struct *floppy;



	DPRINT(("redo_fd_request: CURRENT=%p dev=%s CURRENT->sector=%ld\n",

		CURRENT, CURRENT ? CURRENT->rq_disk->disk_name : "",

		CURRENT ? blk_rq_pos(CURRENT) : 0 ));

	DPRINT(("redo_fd_request: fd_request=%p dev=%s fd_request->sector=%ld\n",

		fd_request, fd_request ? fd_request->rq_disk->disk_name : "",

		fd_request ? blk_rq_pos(fd_request) : 0 ));



	IsFormatting = 0;



repeat:



	if (!CURRENT)

	if (!fd_request) {

		fd_request = elv_next_request(floppy_queue);

		if (!fd_request)

			goto the_end;

		blkdev_dequeue_request(fd_request);

	}



	floppy = CURRENT->rq_disk->private_data;

	floppy = fd_request->rq_disk->private_data;

	drive = floppy - unit;

	type = floppy->type;

	

	if (!UD.connected) {

		/* drive not connected */

		printk(KERN_ERR "Unknown Device: fd%d\n", drive );

		__blk_end_request_cur(CURRENT, -EIO);

		fd_end_request_cur(-EIO);

		goto repeat;

	}
@@ -1426,12 +1433,12 @@ repeat: 
		/* user supplied disk type */

		if (--type >= NUM_DISK_MINORS) {

			printk(KERN_WARNING "fd%d: invalid disk format", drive );

			__blk_end_request_cur(CURRENT, -EIO);

			fd_end_request_cur(-EIO);

			goto repeat;

		}

		if (minor2disktype[type].drive_types > DriveType)  {

			printk(KERN_WARNING "fd%d: unsupported disk format", drive );

			__blk_end_request_cur(CURRENT, -EIO);

			fd_end_request_cur(-EIO);

			goto repeat;

		}

		type = minor2disktype[type].index;
@@ -1440,8 +1447,8 @@ repeat: 
		UD.autoprobe = 0;

	}

	

	if (blk_rq_pos(CURRENT) + 1 > UDT->blocks) {

		__blk_end_request_cur(CURRENT, -EIO);

	if (blk_rq_pos(fd_request) + 1 > UDT->blocks) {

		fd_end_request_cur(-EIO);

		goto repeat;

	}
@@ -1449,9 +1456,9 @@ repeat: 
	del_timer( &motor_off_timer );

		

	ReqCnt = 0;

	ReqCmd = rq_data_dir(CURRENT);

	ReqBlock = blk_rq_pos(CURRENT);

	ReqBuffer = CURRENT->buffer;

	ReqCmd = rq_data_dir(fd_request);

	ReqBlock = blk_rq_pos(fd_request);

	ReqBuffer = fd_request->buffer;

	setup_req_params( drive );

	do_fd_action( drive );

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