public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Timur Tabi <timur.tabi@ammasso.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Will __pa(vmalloc()) ever work?
Date: Fri, 27 May 2005 14:54:53 -0500	[thread overview]
Message-ID: <42977B0D.3040809@ammasso.com> (raw)
In-Reply-To: <20050527192925.GA8250@infradead.org>

Christoph Hellwig wrote:

> It will return the correct physical address for the start of the buffer.
> But given that vmalloc is a non-contingous allocator that's pretty useless.

So as long as the vmalloc'd memory fits inside one page, __pa() will always give the 
correct address?  If so, then can't I just call __pa() for every page in the buffer and 
get a list of physical addresses?  If I can do that, then how the memory be virtually 
contiguous but not physicall contiguous?

> As are physical addresses for anything but low-level architecture code.

I don't understand what that means.

-- 
Timur Tabi
Staff Software Engineer
timur.tabi@ammasso.com

One thing a Southern boy will never say is,
"I don't think duct tape will fix it."
      -- Ed Smylie, NASA engineer for Apollo 13

  reply	other threads:[~2005-05-27 19:55 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-05-27 19:26 Will __pa(vmalloc()) ever work? Timur Tabi
2005-05-27 19:29 ` Christoph Hellwig
2005-05-27 19:54   ` Timur Tabi [this message]
2005-05-27 20:31     ` Arnd Bergmann
2005-05-28 16:16   ` Russell King
2005-05-30  9:38 ` Gerd Knorr
2005-05-31 15:51   ` Timur Tabi
2005-05-31 16:13     ` Gerd Knorr
2005-05-31 18:59       ` Timur Tabi
2005-05-31 20:01         ` Russell King
2005-05-31 20:44         ` Brian Gerst

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=42977B0D.3040809@ammasso.com \
    --to=timur.tabi@ammasso.com \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    /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