Re: [PATCH 5/6] ide: remove ide_execute_pkt_cmd()

[Borislav Petkov <petkovbb@googlemail.com>]

On Tue, Feb 10, 2009 at 12:20:19AM +0100, Bartlomiej Zolnierkiewicz wrote:
> From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> Subject: [PATCH] ide: remove ide_execute_pkt_cmd()
> 
> * Pass command structure to ide_execute_command() and skip
>   __ide_set_handler() for ATAPI protocols.
> 
> * Convert ide_issue_pc() to always use ide_execute_command()
>   and remove no longer needed ide_execute_pkt_cmd().
> 
> There should be no functional changes caused by this patch.
> 
> Cc: Borislav Petkov <petkovbb@gmail.com>
> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
> ---
>  drivers/ide/ide-atapi.c    |   15 +++++++--------
>  drivers/ide/ide-iops.c     |   23 ++++++-----------------
>  drivers/ide/ide-taskfile.c |    6 ++----
>  include/linux/ide.h        |    5 ++---
>  4 files changed, 17 insertions(+), 32 deletions(-)
> 
> Index: b/drivers/ide/ide-atapi.c
> ===================================================================
> --- a/drivers/ide/ide-atapi.c
> +++ b/drivers/ide/ide-atapi.c
> @@ -481,6 +481,7 @@ static void ide_init_packet_cmd(struct i
>  	cmd->protocol  = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
>  	cmd->tf_flags |= IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
>  			 IDE_TFLAG_OUT_FEATURE | tf_flags;
> +	cmd->tf.command = ATA_CMD_PACKET;
>  	cmd->tf.feature = dma;		/* Use PIO/DMA */
>  	cmd->tf.lbam    = bcount & 0xff;
>  	cmd->tf.lbah    = (bcount >> 8) & 0xff;
> @@ -626,6 +627,7 @@ ide_startstop_t ide_issue_pc(ide_drive_t
>  	unsigned int timeout;
>  	u32 tf_flags;
>  	u16 bcount;
> +	u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);

How about we finally add those check macros in block layer fashion like
blk_pc_request et al and do

#define drv_can_drq_interrupt(drive)	((drive)->atapi_flags &	IDE_AFLAG_DRQ_INTERRUPT)
...


or similar instead of wasting stack space? It'll also read better in the if()
check:

if (drv_can_irq_interrupt(drive)) { ...

If it's ok with you, I'll whip up patch(es) later.

>  
>  	if (dev_is_idecd(drive)) {
>  		tf_flags = IDE_TFLAG_OUT_NSECT | IDE_TFLAG_OUT_LBAL;
> @@ -675,17 +677,14 @@ ide_startstop_t ide_issue_pc(ide_drive_t
>  
>  	(void)do_rw_taskfile(drive, cmd);
>  
> -	/* Issue the packet command */
> -	if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
> +	if (drq_int) {
>  		if (drive->dma)
>  			drive->waiting_for_dma = 0;
>  		hwif->expiry = expiry;
> -		ide_execute_command(drive, ATA_CMD_PACKET, ide_transfer_pc,
> -				    timeout);
> -		return ide_started;
> -	} else {
> -		ide_execute_pkt_cmd(drive);
> -		return ide_transfer_pc(drive);
>  	}
> +
> +	ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
> +
> +	return drq_int ? ide_started : ide_transfer_pc(drive);
>  }
>  EXPORT_SYMBOL_GPL(ide_issue_pc);
> Index: b/drivers/ide/ide-iops.c
> ===================================================================
> --- a/drivers/ide/ide-iops.c
> +++ b/drivers/ide/ide-iops.c
> @@ -451,7 +451,7 @@ EXPORT_SYMBOL(ide_set_handler);
>  /**
>   *	ide_execute_command	-	execute an IDE command
>   *	@drive: IDE drive to issue the command against
> - *	@command: command byte to write
> + *	@cmd: command
>   *	@handler: handler for next phase
>   *	@timeout: timeout for command
>   *
> @@ -461,15 +461,16 @@ EXPORT_SYMBOL(ide_set_handler);
>   *	should go via this function or do equivalent locking.
>   */
>  
> -void ide_execute_command(ide_drive_t *drive, u8 cmd, ide_handler_t *handler,
> -			 unsigned timeout)
> +void ide_execute_command(ide_drive_t *drive, struct ide_cmd *cmd,
> +			 ide_handler_t *handler, unsigned timeout)
>  {
>  	ide_hwif_t *hwif = drive->hwif;
>  	unsigned long flags;
>  
>  	spin_lock_irqsave(&hwif->lock, flags);
> -	__ide_set_handler(drive, handler, timeout);
> -	hwif->tp_ops->exec_command(hwif, cmd);
> +	if (cmd->protocol != ATAPI_PROT_DMA && cmd->protocol != ATAPI_PROT_PIO)
> +		__ide_set_handler(drive, handler, timeout);
> +	hwif->tp_ops->exec_command(hwif, cmd->tf.command);
>  	/*
>  	 * Drive takes 400nS to respond, we must avoid the IRQ being
>  	 * serviced before that.
> @@ -480,18 +481,6 @@ void ide_execute_command(ide_drive_t *dr
>  	spin_unlock_irqrestore(&hwif->lock, flags);
>  }
>  
> -void ide_execute_pkt_cmd(ide_drive_t *drive)
> -{
> -	ide_hwif_t *hwif = drive->hwif;
> -	unsigned long flags;
> -
> -	spin_lock_irqsave(&hwif->lock, flags);
> -	hwif->tp_ops->exec_command(hwif, ATA_CMD_PACKET);
> -	ndelay(400);
> -	spin_unlock_irqrestore(&hwif->lock, flags);
> -}
> -EXPORT_SYMBOL_GPL(ide_execute_pkt_cmd);
> -
>  /*
>   * ide_wait_not_busy() waits for the currently selected device on the hwif
>   * to report a non-busy status, see comments in ide_probe_port().
> Index: b/drivers/ide/ide-taskfile.c
> ===================================================================
> --- a/drivers/ide/ide-taskfile.c
> +++ b/drivers/ide/ide-taskfile.c
> @@ -97,8 +97,7 @@ ide_startstop_t do_rw_taskfile(ide_drive
>  	case ATA_PROT_NODATA:
>  		if (handler == NULL)
>  			handler = task_no_data_intr;
> -		ide_execute_command(drive, tf->command, handler,
> -				    WAIT_WORSTCASE);
> +		ide_execute_command(drive, cmd, handler, WAIT_WORSTCASE);
>  		return ide_started;
>  	case ATA_PROT_DMA:
>  		if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
> @@ -106,8 +105,7 @@ ide_startstop_t do_rw_taskfile(ide_drive
>  		    dma_ops->dma_setup(drive, cmd))
>  			return ide_stopped;
>  		hwif->expiry = dma_ops->dma_expiry;
> -		ide_execute_command(drive, tf->command, ide_dma_intr,
> -				    2 * WAIT_CMD);
> +		ide_execute_command(drive, cmd, ide_dma_intr, 2 * WAIT_CMD);
>  		dma_ops->dma_start(drive);
>  	default:
>  		return ide_started;
> Index: b/include/linux/ide.h
> ===================================================================
> --- a/include/linux/ide.h
> +++ b/include/linux/ide.h
> @@ -1135,9 +1135,8 @@ void ide_kill_rq(ide_drive_t *, struct r
>  void __ide_set_handler(ide_drive_t *, ide_handler_t *, unsigned int);
>  void ide_set_handler(ide_drive_t *, ide_handler_t *, unsigned int);
>  
> -void ide_execute_command(ide_drive_t *, u8, ide_handler_t *, unsigned int);
> -
> -void ide_execute_pkt_cmd(ide_drive_t *);
> +void ide_execute_command(ide_drive_t *, struct ide_cmd *, ide_handler_t *,
> +			 unsigned int);
>  
>  void ide_pad_transfer(ide_drive_t *, int, int);
>  

-- 
Regards/Gruss,
    Boris.