* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
@ 2007-04-02 8:28 Joerg Schilling
2007-04-02 13:54 ` Alan Stern
0 siblings, 1 reply; 6+ messages in thread
From: Joerg Schilling @ 2007-04-02 8:28 UTC (permalink / raw)
To: stern; +Cc: dougg, James.Bottomley, jens.axboe, linux-kernel
Hi,
this is a repost as I like to know the current state of the problem...
The USB DMA size problem is known to exist on Linux since February 2004.
I am still in hope that there will be a fix soon.
/*--------------------------------------------------------------------------*/
Alan Stern <stern@rowland.harvard.edu> wrote:
> Well, if Doug wants to reduce the value returned by SG_GET_RESERVED_SIZE,
> it's okay with me. An advantage of doing this is that older versions of
> cdrecord would then work correctly.
>
> However you don't seem to realize that people can use programs like
> cdrecord with devices whose drivers don't support SG_GET_RESERVED_SIZE --
> because that ioctl works only with sg. Programs would have to try
> SG_GET_RESERVED_SIZE and if it faied, then try BLKSECTGET.
Is there any reason not to have one single ioctl for one basic feature?
> Remember also, the "reserved size" is _not_ the maximum allowed size of a
> DMA transfer. Rather, it is the size of an internal buffer maintained by
> sg. It's legal to do an I/O transfer larger than the "reserved size", but
> it is not legal to do an I/O transfer larger than max_sectors.
At the time the call SG_GET_RESERVED_SIZE has been discussed/defined, we did
originally agree that the max value should be limited to what the HW allows
as DMA size. This is why I did originally files a bug against
SG_GET_RESERVED_SIZE.
/*--------------------------------------------------------------------------*/
Jörg
--
EMail:joerg@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin
js@cs.tu-berlin.de (uni)
schilling@fokus.fraunhofer.de (work) Blog: http://schily.blogspot.com/
URL: http://cdrecord.berlios.de/old/private/ ftp://ftp.berlios.de/pub/schily
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
2007-04-02 8:28 [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls Joerg Schilling
@ 2007-04-02 13:54 ` Alan Stern
0 siblings, 0 replies; 6+ messages in thread
From: Alan Stern @ 2007-04-02 13:54 UTC (permalink / raw)
To: Joerg Schilling
Cc: dougg, James Bottomley, jens.axboe, SCSI development list,
Kernel development list
On Mon, 2 Apr 2007, Joerg Schilling wrote:
> Hi,
>
> this is a repost as I like to know the current state of the problem...
>
> The USB DMA size problem is known to exist on Linux since February 2004.
> I am still in hope that there will be a fix soon.
Me too. I submitted the most recent version of the patch (labelled as857)
over a month ago and have received essentially no feedback on it.
Douglas, James... What's the story?
Alan Stern
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
@ 2007-04-02 13:54 ` Alan Stern
0 siblings, 0 replies; 6+ messages in thread
From: Alan Stern @ 2007-04-02 13:54 UTC (permalink / raw)
To: Joerg Schilling
Cc: dougg, James Bottomley, jens.axboe, SCSI development list,
Kernel development list
On Mon, 2 Apr 2007, Joerg Schilling wrote:
> Hi,
>
> this is a repost as I like to know the current state of the problem...
>
> The USB DMA size problem is known to exist on Linux since February 2004.
> I am still in hope that there will be a fix soon.
Me too. I submitted the most recent version of the patch (labelled as857)
over a month ago and have received essentially no feedback on it.
Douglas, James... What's the story?
Alan Stern
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
2007-04-02 13:54 ` Alan Stern
(?)
@ 2007-04-02 14:23 ` Jens Axboe
2007-04-02 14:34 ` James Bottomley
-1 siblings, 1 reply; 6+ messages in thread
From: Jens Axboe @ 2007-04-02 14:23 UTC (permalink / raw)
To: Alan Stern
Cc: Joerg Schilling, dougg, James Bottomley, SCSI development list,
Kernel development list
On Mon, Apr 02 2007, Alan Stern wrote:
> On Mon, 2 Apr 2007, Joerg Schilling wrote:
>
> > Hi,
> >
> > this is a repost as I like to know the current state of the problem...
> >
> > The USB DMA size problem is known to exist on Linux since February 2004.
> > I am still in hope that there will be a fix soon.
>
> Me too. I submitted the most recent version of the patch (labelled as857)
> over a month ago and have received essentially no feedback on it.
>
> Douglas, James... What's the story?
FWIW, it had my ack, I think we were just waiting for Doug to ack the sg
bits.
--
Jens Axboe
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
2007-04-02 14:23 ` Jens Axboe
@ 2007-04-02 14:34 ` James Bottomley
0 siblings, 0 replies; 6+ messages in thread
From: James Bottomley @ 2007-04-02 14:34 UTC (permalink / raw)
To: Jens Axboe
Cc: Alan Stern, Joerg Schilling, dougg, SCSI development list,
Kernel development list
On Mon, 2007-04-02 at 16:23 +0200, Jens Axboe wrote:
> FWIW, it had my ack, I think we were just waiting for Doug to ack the sg
> bits.
And there's really nothing I can do (well, except write the thing) since
the changes are not in any SCSI pieces I maintain directly ... they're
block and sg.
James
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls
@ 2007-04-02 14:34 ` James Bottomley
0 siblings, 0 replies; 6+ messages in thread
From: James Bottomley @ 2007-04-02 14:34 UTC (permalink / raw)
To: Jens Axboe
Cc: Alan Stern, Joerg Schilling, dougg, SCSI development list,
Kernel development list
On Mon, 2007-04-02 at 16:23 +0200, Jens Axboe wrote:
> FWIW, it had my ack, I think we were just waiting for Doug to ack the sg
> bits.
And there's really nothing I can do (well, except write the thing) since
the changes are not in any SCSI pieces I maintain directly ... they're
block and sg.
James
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2007-04-02 14:37 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-04-02 8:28 [PATCH] Block layer: separate out queue-oriented ioctls Re: [PATCH] Block layer: separate out queue-oriented ioctls Joerg Schilling
2007-04-02 13:54 ` Alan Stern
2007-04-02 13:54 ` Alan Stern
2007-04-02 14:23 ` Jens Axboe
2007-04-02 14:34 ` James Bottomley
2007-04-02 14:34 ` James Bottomley
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