Linux-USB Archive on lore.kernel.org
 help / color / Atom feed
From: Finn Thain <fthain@telegraphics.com.au>
To: Ming Lei <ming.lei@redhat.com>
Cc: linux-scsi@vger.kernel.org,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	James Bottomley <James.Bottomley@HansenPartnership.com>,
	Bart Van Assche <bvanassche@acm.org>,
	Hannes Reinecke <hare@suse.com>, Christoph Hellwig <hch@lst.de>,
	Jim Gill <jgill@vmware.com>, Cathy Avery <cavery@redhat.com>,
	"Ewan D . Milne" <emilne@redhat.com>,
	Brian King <brking@us.ibm.com>,
	James Smart <james.smart@broadcom.com>,
	"Juergen E . Fischer" <fischer@norbit.de>,
	Michael Schmitz <schmitzmic@gmail.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	devel@driverdev.osuosl.org, linux-usb@vger.kernel.org,
	Dan Carpenter <dan.carpenter@oracle.com>,
	Benjamin Block <bblock@linux.ibm.com>
Subject: Re: [PATCH V5 11/16] scsi: aha152x: use sg helper to operate scatterlist
Date: Tue, 18 Jun 2019 13:54:12 +1000 (AEST)
Message-ID: <alpine.LNX.2.21.1906181352030.8@nippy.intranet> (raw)
In-Reply-To: <20190618013757.22401-12-ming.lei@redhat.com>

On Tue, 18 Jun 2019, Ming Lei wrote:

> From: Finn Thain <fthain@telegraphics.com.au>
> 
> Use the scatterlist iterators and remove direct indexing of the
> scatterlist array.
> 
> This way allows us to pre-allocate one small scatterlist, which can be
> chained with one runtime allocated scatterlist if the pre-allocated one
> isn't enough for the whole request.
> 
> Finn added the change to replace SCp.buffers_residual with sg_is_last()
> for fixing updating it, and the similar change has been applied on
> NCR5380.c
> 
> Cc: Finn Thain <fthain@telegraphics.com.au>
> Signed-off-by: Ming Lei <ming.lei@redhat.com>

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>

> ---
>  drivers/scsi/aha152x.c | 46 +++++++++++++++++++++---------------------
>  1 file changed, 23 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c
> index 97872838b983..f07f3fa9b58d 100644
> --- a/drivers/scsi/aha152x.c
> +++ b/drivers/scsi/aha152x.c
> @@ -948,7 +948,6 @@ static int aha152x_internal_queue(struct scsi_cmnd *SCpnt,
>  	   SCp.ptr              : buffer pointer
>  	   SCp.this_residual    : buffer length
>  	   SCp.buffer           : next buffer
> -	   SCp.buffers_residual : left buffers in list
>  	   SCp.phase            : current state of the command */
>  
>  	if ((phase & resetting) || !scsi_sglist(SCpnt)) {
> @@ -956,13 +955,11 @@ static int aha152x_internal_queue(struct scsi_cmnd *SCpnt,
>  		SCpnt->SCp.this_residual = 0;
>  		scsi_set_resid(SCpnt, 0);
>  		SCpnt->SCp.buffer           = NULL;
> -		SCpnt->SCp.buffers_residual = 0;
>  	} else {
>  		scsi_set_resid(SCpnt, scsi_bufflen(SCpnt));
>  		SCpnt->SCp.buffer           = scsi_sglist(SCpnt);
>  		SCpnt->SCp.ptr              = SG_ADDRESS(SCpnt->SCp.buffer);
>  		SCpnt->SCp.this_residual    = SCpnt->SCp.buffer->length;
> -		SCpnt->SCp.buffers_residual = scsi_sg_count(SCpnt) - 1;
>  	}
>  
>  	DO_LOCK(flags);
> @@ -2030,10 +2027,9 @@ static void datai_run(struct Scsi_Host *shpnt)
>  				}
>  
>  				if (CURRENT_SC->SCp.this_residual == 0 &&
> -				    CURRENT_SC->SCp.buffers_residual > 0) {
> +				    !sg_is_last(CURRENT_SC->SCp.buffer)) {
>  					/* advance to next buffer */
> -					CURRENT_SC->SCp.buffers_residual--;
> -					CURRENT_SC->SCp.buffer++;
> +					CURRENT_SC->SCp.buffer = sg_next(CURRENT_SC->SCp.buffer);
>  					CURRENT_SC->SCp.ptr           = SG_ADDRESS(CURRENT_SC->SCp.buffer);
>  					CURRENT_SC->SCp.this_residual = CURRENT_SC->SCp.buffer->length;
>  				}
> @@ -2136,10 +2132,10 @@ static void datao_run(struct Scsi_Host *shpnt)
>  			CMD_INC_RESID(CURRENT_SC, -2 * data_count);
>  		}
>  
> -		if(CURRENT_SC->SCp.this_residual==0 && CURRENT_SC->SCp.buffers_residual>0) {
> +		if (CURRENT_SC->SCp.this_residual == 0 &&
> +		    !sg_is_last(CURRENT_SC->SCp.buffer)) {
>  			/* advance to next buffer */
> -			CURRENT_SC->SCp.buffers_residual--;
> -			CURRENT_SC->SCp.buffer++;
> +			CURRENT_SC->SCp.buffer = sg_next(CURRENT_SC->SCp.buffer);
>  			CURRENT_SC->SCp.ptr           = SG_ADDRESS(CURRENT_SC->SCp.buffer);
>  			CURRENT_SC->SCp.this_residual = CURRENT_SC->SCp.buffer->length;
>  		}
> @@ -2158,22 +2154,26 @@ static void datao_run(struct Scsi_Host *shpnt)
>  static void datao_end(struct Scsi_Host *shpnt)
>  {
>  	if(TESTLO(DMASTAT, DFIFOEMP)) {
> -		int data_count = (DATA_LEN - scsi_get_resid(CURRENT_SC)) -
> -			GETSTCNT();
> +		u32 datao_cnt = GETSTCNT();
> +		int datao_out = DATA_LEN - scsi_get_resid(CURRENT_SC);
> +		int done;
> +		struct scatterlist *sg = scsi_sglist(CURRENT_SC);
>  
> -		CMD_INC_RESID(CURRENT_SC, data_count);
> +		CMD_INC_RESID(CURRENT_SC, datao_out - datao_cnt);
>  
> -		data_count -= CURRENT_SC->SCp.ptr -
> -			SG_ADDRESS(CURRENT_SC->SCp.buffer);
> -		while(data_count>0) {
> -			CURRENT_SC->SCp.buffer--;
> -			CURRENT_SC->SCp.buffers_residual++;
> -			data_count -= CURRENT_SC->SCp.buffer->length;
> +		done = scsi_bufflen(CURRENT_SC) - scsi_get_resid(CURRENT_SC);
> +		/* Locate the first SG entry not yet sent */
> +		while (done > 0 && !sg_is_last(sg)) {
> +			if (done < sg->length)
> +				break;
> +			done -= sg->length;
> +			sg = sg_next(sg);
>  		}
> -		CURRENT_SC->SCp.ptr = SG_ADDRESS(CURRENT_SC->SCp.buffer) -
> -			data_count;
> -		CURRENT_SC->SCp.this_residual = CURRENT_SC->SCp.buffer->length +
> -			data_count;
> +
> +		CURRENT_SC->SCp.buffer = sg;
> +		CURRENT_SC->SCp.ptr = SG_ADDRESS(CURRENT_SC->SCp.buffer) + done;
> +		CURRENT_SC->SCp.this_residual = CURRENT_SC->SCp.buffer->length -
> +			done;
>  	}
>  
>  	SETPORT(SXFRCTL0, CH1|CLRCH1|CLRSTCNT);
> @@ -2501,7 +2501,7 @@ static void get_command(struct seq_file *m, struct scsi_cmnd * ptr)
>  
>  	seq_printf(m, "); resid=%d; residual=%d; buffers=%d; phase |",
>  		scsi_get_resid(ptr), ptr->SCp.this_residual,
> -		ptr->SCp.buffers_residual);
> +		sg_nents(ptr->SCp.buffer) - 1);
>  
>  	if (ptr->SCp.phase & not_issued)
>  		seq_puts(m, "not issued|");
> 

  reply index

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-18  1:37 [PATCH V5 00/16] " Ming Lei
2019-06-18  1:37 ` [PATCH V5 01/16] scsi: vmw_pscsi: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 02/16] scsi: advansys: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 03/16] scsi: lpfc: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 04/16] scsi: mvumi: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 05/16] scsi: ipr: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 06/16] scsi: pmcraid: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 07/16] usb: image: microtek: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 08/16] staging: unisys: visorhba: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 09/16] staging: rtsx: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 10/16] s390: zfcp_fc: " Ming Lei
2019-06-24 15:13   ` Steffen Maier
2019-06-25  1:19     ` Ming Lei
2019-06-25  2:01       ` Finn Thain
2019-06-25  2:30         ` Ming Lei
2019-06-25  3:42           ` Finn Thain
2019-06-25 10:51       ` Steffen Maier
2019-06-26  3:07         ` Ming Lei
2019-06-26  8:17           ` Steffen Maier
2019-06-18  1:37 ` [PATCH V5 11/16] scsi: aha152x: " Ming Lei
2019-06-18  3:54   ` Finn Thain [this message]
2019-06-18  1:37 ` [PATCH V5 12/16] scsi: imm: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 13/16] scsi: pcmcia: nsp_cs: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 14/16] scsi: ppa: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 15/16] scsi: wd33c93: " Ming Lei
2019-06-18  1:37 ` [PATCH V5 16/16] NCR5380: Support chained sg lists Ming Lei
2019-06-19  0:29 ` [PATCH V5 00/16] use sg helper to operate scatterlist Martin K. Petersen
2019-06-19 19:43   ` Bart Van Assche
2019-06-19 19:55     ` Martin K. Petersen
2019-06-24 12:40       ` Ming Lei
2019-06-24 12:54         ` Martin K. Petersen

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=alpine.LNX.2.21.1906181352030.8@nippy.intranet \
    --to=fthain@telegraphics.com.au \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=bblock@linux.ibm.com \
    --cc=brking@us.ibm.com \
    --cc=bvanassche@acm.org \
    --cc=cavery@redhat.com \
    --cc=dan.carpenter@oracle.com \
    --cc=devel@driverdev.osuosl.org \
    --cc=emilne@redhat.com \
    --cc=fischer@norbit.de \
    --cc=gregkh@linuxfoundation.org \
    --cc=hare@suse.com \
    --cc=hch@lst.de \
    --cc=james.smart@broadcom.com \
    --cc=jgill@vmware.com \
    --cc=linux-scsi@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=ming.lei@redhat.com \
    --cc=schmitzmic@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-USB Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-usb/0 linux-usb/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-usb linux-usb/ https://lore.kernel.org/linux-usb \
		linux-usb@vger.kernel.org linux-usb@archiver.kernel.org
	public-inbox-index linux-usb


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-usb


AGPL code for this site: git clone https://public-inbox.org/ public-inbox