From: James Bottomley <James.Bottomley@SteelEye.com>
To: Roland Dreier <roland@topspin.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>,
linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org
Subject: Re: [PATCH] 2.4 use __dma_buffer in scsi.h
Date: Thu, 13 Jun 2002 13:52:39 -0400 [thread overview]
Message-ID: <200206131752.g5DHqdm24049@localhost.localdomain> (raw)
In-Reply-To: Message from Roland Dreier <roland@topspin.com> of "13 Jun 2002 10:42:16 PDT." <52fzzr2hzb.fsf@topspin.com>
roland@topspin.com said:
> Out of curiousity, how do you deal with someone writing to Scsi_Cmnd
> _before_ the DMA and having that data lost when pci_map_single() with
> PCI_DMA_FROMDEVICE invalidates the cache before writeback?
The the pci_map_single with PCI_DMA_FROMDEVICE is supposed to do a writeback
invalidate cycle on the cache when pci_sync_single is called (at least this is
how it is implemented on parisc) so any writes up to the sync point are
flushed to memory before the cache line is trashed.
James
next prev parent reply other threads:[~2002-06-13 17:52 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-06-13 2:17 James Bottomley
2002-06-13 17:42 ` Roland Dreier
2002-06-13 17:52 ` James Bottomley [this message]
-- strict thread matches above, loose matches on Subject: below --
2002-06-13 0:24 Roland Dreier
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=200206131752.g5DHqdm24049@localhost.localdomain \
--to=james.bottomley@steeleye.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=roland@topspin.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
all inboxes | Powered by JetHome®