From: Manfred Spraul <manfred@colorfullife.com>
To: "Imran Badr" <imran.badr@cavium.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Calculating kernel logical address ..
Date: Fri, 06 Sep 2002 17:44:29 +0200 [thread overview]
Message-ID: <3D78CD5D.9060002@colorfullife.com> (raw)
> adr = user_address;
> pgd_offset(current->mm, adr);
>
> if (!pgd_none(*pgd)) {
> pmd = pmd_offset(pgd, adr);
> if (!pmd_none(*pmd)) {
> ptep = pte_offset(pmd, adr);
> pte = *ptep;
> if(pte_present(pte)) {
> kaddr = (unsigned long) page_address(pte_page(pte));
> kaddr |= (adr & (PAGE_SIZE - 1));
> }
> }
> }
>
> Will this code always give me correct kernel logical address?
>
What about
kmalloc_buffer+(user_address-vma->vm_start)
?
A driver should avoid accessing the page tables.
--
Manfred
next reply other threads:[~2002-09-06 15:39 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-09-06 15:44 Manfred Spraul [this message]
2002-09-06 17:13 ` Calculating kernel logical address Imran Badr
2002-09-07 1:57 ` Daniel Phillips
-- strict thread matches above, loose matches on Subject: below --
2002-09-09 21:19 Manfred Spraul
2002-09-09 21:47 ` Andrew Morton
2002-09-10 17:01 ` Manfred Spraul
2002-09-09 21:02 Manfred Spraul
2002-09-09 21:07 ` Imran Badr
2002-09-09 17:06 Imran Badr
2002-09-09 17:29 ` Richard B. Johnson
2002-09-09 17:23 ` David S. Miller
2002-09-09 17:34 ` Martin J. Bligh
2002-09-09 17:40 ` Daniel Phillips
2002-09-09 17:31 ` Imran Badr
2002-09-09 18:00 ` Richard B. Johnson
2002-09-09 18:12 ` Imran Badr
2002-09-09 18:27 ` Daniel Phillips
2002-09-09 18:41 ` Imran Badr
2002-09-09 21:55 ` Alan Cox
2002-09-09 22:52 ` Imran Badr
2002-09-09 23:09 ` Alan Cox
2002-09-09 18:13 ` Jesse Barnes
2002-09-09 18:25 ` Daniel Phillips
2002-09-09 19:40 ` Andrew Morton
2002-09-09 20:41 ` Daniel Phillips
2002-09-10 6:43 ` Jens Axboe
2002-09-10 7:12 ` Andrew Morton
2002-09-09 18:42 ` Andrew Morton
2002-09-10 7:03 ` Gerd Knorr
2002-09-09 18:16 ` Kurt Ferreira
2002-09-09 18:17 ` David S. Miller
2002-09-09 18:17 ` Daniel Phillips
2002-09-09 18:43 ` Richard B. Johnson
2002-09-09 18:50 ` Daniel Phillips
2002-09-09 18:57 ` Richard B. Johnson
2002-09-09 18:08 ` Andrew Morton
2002-09-09 18:23 ` Daniel Phillips
2002-09-09 18:49 ` Imran Badr
2002-09-09 18:46 ` David S. Miller
2002-09-09 19:06 ` Daniel Phillips
2002-09-09 19:14 ` Andrew Morton
2002-09-09 19:23 ` Imran Badr
2002-09-06 3:23 side-by-side Re: BYTE Unix Benchmarks Version 3.6 Daniel Phillips
2002-09-06 3:34 ` Calculating kernel logical address Imran Badr
2002-09-07 1:44 ` Daniel Phillips
2002-09-08 0:01 ` David S. Miller
2002-09-08 18:44 ` Daniel Phillips
2002-09-09 5:00 ` David S. Miller
2002-09-09 5:17 ` Daniel Phillips
2002-09-09 5:28 ` David S. Miller
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