public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jeff Garzik <jgarzik@pobox.com>
To: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Stefan Smietanowski <stesmi@stesmi.com>,
	linux-ide@vger.kernel.org,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@osdl.org>
Subject: Re: [PATCH] speed up SATA
Date: Sat, 27 Mar 2004 19:08:44 -0500	[thread overview]
Message-ID: <4066178C.5020605@pobox.com> (raw)
In-Reply-To: <200403280113.58555.bzolnier@elka.pw.edu.pl>

Bartlomiej Zolnierkiewicz wrote:
> On Sunday 28 of March 2004 00:40, Jeff Garzik wrote:
> 
>>Jeff Garzik wrote:
>>
>>>That's the main limitation on request size right now...  libata limits
>>>S/G table entries to 128[1], so a perfectly aligned, fully merged
>>
>>    ...
>>
>>[1] because even though the block layer properly splits on segment
>>boundaries, pci_map_sg() may violate those boundaries (James B and
>>others are working on fixing this).  So...  for right now the driver
>>must check the s/g entry boundaries after DMA mapping, and split them
>>(again) if necessary.  IDE does this in ide_build_dmatable().
> 
> 
> You are right but small clarification is needed: code in ide_build_dmatable()
> predates segment boundary support in block layer (IDE never relied on it).

Agreed...  I'm saying it's still needed.

When the iommu layer knows about the boundaries it should respect, that 
code can be removed from libata and drivers/ide, IMO...  But also 
double-check and make sure IDE driver supports the worst case, by 
limiting to 128 PRD entries, not 256.

	Jeff




  reply	other threads:[~2004-03-28  0:09 UTC|newest]

Thread overview: 115+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-03-27 22:37 [PATCH] speed up SATA Jeff Garzik
2004-03-27 23:04 ` Stefan Smietanowski
2004-03-27 23:11   ` Jeff Garzik
2004-03-28  7:23     ` Stefan Smietanowski
2004-03-28 15:37       ` Bartlomiej Zolnierkiewicz
2004-03-27 23:32   ` Bartlomiej Zolnierkiewicz
2004-03-27 23:36     ` Jeff Garzik
2004-03-27 23:40       ` Jeff Garzik
2004-03-28  0:13         ` Bartlomiej Zolnierkiewicz
2004-03-28  0:08           ` Jeff Garzik [this message]
2004-03-29 11:42       ` Pavel Machek
2004-03-27 23:37 ` Nick Piggin
2004-03-27 23:44   ` Jeff Garzik
2004-03-27 23:47     ` Nick Piggin
2004-03-27 23:59       ` Jeff Garzik
2004-03-28 14:10         ` Jens Axboe
2004-03-28 17:31           ` Jeff Garzik
2004-03-28 17:35             ` Jens Axboe
2004-03-28 17:48               ` Jeff Garzik
2004-03-28 17:54                 ` Jens Axboe
2004-03-28 18:08                   ` Jamie Lokier
2004-03-28 18:15                     ` Jens Axboe
2004-03-28 18:55                       ` Jeff Garzik
2004-03-29  8:09                         ` Jens Axboe
2004-03-29 12:41                           ` Jamie Lokier
2004-03-29 12:44                             ` Jens Axboe
2004-03-29 12:50                               ` Jamie Lokier
2004-03-29 13:05                               ` Arjan van de Ven
2004-03-29 13:08                                 ` Jens Axboe
2004-03-30  8:13                                   ` Kurt Garloff
2004-03-30 11:40                                     ` Jens Axboe
2004-03-29 17:19                                 ` Craig I. Hagan
2004-03-29 18:19                           ` Jeff Garzik
2004-03-28 19:06                       ` Jeff Garzik
2004-03-28 18:12                   ` William Lee Irwin III
2004-03-28 18:17                     ` Jens Axboe
2004-03-28 18:30                     ` Bartlomiej Zolnierkiewicz
2004-03-28 18:30                       ` Jens Axboe
2004-03-28 18:45                         ` Bartlomiej Zolnierkiewicz
2004-03-28 18:59                           ` Jeff Garzik
2004-03-28 20:32                             ` Andrew Morton
2004-03-28 20:45                               ` Jeff Garzik
2004-03-29  0:55                             ` Andrea Arcangeli
2004-03-29  4:02                               ` Jeff Garzik
2004-03-29 13:04                                 ` Andrea Arcangeli
2004-03-29 19:45                                   ` Jeff Garzik
2004-03-30 11:09                                     ` Jens Axboe
2004-03-30 15:54                                       ` Timothy Miller
2004-03-30 16:20                                       ` Jeff Garzik
2004-03-30 18:05                                       ` Timothy Miller
2004-03-30 17:50                                         ` Jeff Garzik
2004-03-30 18:19                                           ` Timothy Miller
2004-03-29  4:29                               ` Wim Coekaerts
2004-03-29  7:32                                 ` Denis Vlasenko
2004-03-29  8:13                                 ` Jens Axboe
2004-03-29 13:05                                 ` Andrea Arcangeli
2004-03-29  4:31                               ` William Lee Irwin III
2004-03-29  4:57                               ` Jeff Garzik
2004-03-28 19:52                       ` Nuno Silva
2004-03-28 20:02                         ` Jeff Garzik
2004-03-28  0:06     ` Jeff Garzik
2004-03-28  0:15       ` Nick Piggin
2004-03-28  0:49         ` Jeff Garzik
2004-03-28  1:02           ` Andrew Morton
2004-03-28  1:09             ` Jeff Garzik
2004-03-28 13:59               ` Jens Axboe
2004-03-28 17:29                 ` Jeff Garzik
2004-03-28 17:31                   ` Jens Axboe
2004-03-28 13:51           ` Jamie Lokier
2004-03-28 17:24             ` Jeff Garzik
2004-03-28 17:36               ` Jamie Lokier
2004-03-28 17:54                 ` Jeff Garzik
2004-03-28 20:50                   ` Eric D. Mudama
2004-04-02 10:11                 ` Jeremy Higdon
2004-04-02 16:11                   ` Jamie Lokier
2004-04-03 10:48                     ` Jeremy Higdon
2004-04-03 13:49                       ` Jamie Lokier
2004-03-28 17:40               ` Jens Axboe
2004-03-28 17:49                 ` Jeff Garzik
2004-03-28 17:55                   ` Jens Axboe
2004-03-28 18:04                     ` Jeff Garzik
2004-03-28 18:09                       ` Jens Axboe
2004-03-28 20:12                         ` Jeff Garzik
2004-03-28 20:54                           ` Eric D. Mudama
2004-03-28  7:32       ` Stefan Smietanowski
2004-03-28 20:25         ` Jeff Garzik
2004-03-28 21:16           ` Stefan Smietanowski
2004-03-28 21:26             ` Jeff Garzik
2004-03-28 14:08     ` Jens Axboe
2004-03-28 17:38       ` Jeff Garzik
2004-03-28 17:45         ` Jens Axboe
2004-03-28 20:21       ` Jeff Garzik
2004-03-28  0:07   ` Andrew Morton
2004-03-28  0:21     ` Nick Piggin
2004-03-28  4:40   ` Eric D. Mudama
2004-03-28  6:56     ` Nick Piggin
2004-03-28 20:33       ` Eric D. Mudama
2004-03-28 20:59         ` Eric D. Mudama
2004-03-29  1:30           ` Nick Piggin
2004-03-29  5:24             ` Eric D. Mudama
2004-03-29 13:03               ` Jamie Lokier
2004-03-29 11:36 ` Pavel Machek
2004-03-29 18:46   ` David Lang
2004-03-29 20:13     ` Jeff Garzik
2004-03-30  5:55   ` Eric D. Mudama
2004-03-30 11:54 ` Marc Bevand
2004-03-30 13:07   ` Jens Axboe
2004-03-30 13:48     ` Marc Bevand
2004-03-30 13:49       ` Jens Axboe
2004-03-30 15:31   ` Jeff Garzik
2004-03-30 17:42   ` Jeff Garzik
2004-03-31  9:12     ` Marc Bevand
  -- strict thread matches above, loose matches on Subject: below --
2004-03-31  5:47 Marcus Hartig
2004-03-31  6:56 ` Jeff Garzik
2004-03-31 16:07   ` Marcus Hartig

Reply instructions:

You may reply publicly 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=4066178C.5020605@pobox.com \
    --to=jgarzik@pobox.com \
    --cc=B.Zolnierkiewicz@elka.pw.edu.pl \
    --cc=akpm@osdl.org \
    --cc=linux-ide@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=stesmi@stesmi.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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox