From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 30 Jun 2008 20:03:23 +0200 From: Pierre Ossman Subject: How to alloc highmem page below 4GB on i386? Message-ID: <20080630200323.2a5992cd@mjolnir.drzeus.cx> Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg=PGP-SHA1; boundary="=_freyr.drzeus.cx-10147-1214848374-0001-2" Sender: owner-linux-mm@kvack.org Return-Path: To: LKML , linux-mm@kvack.org List-ID: This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_freyr.drzeus.cx-10147-1214848374-0001-2 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Simple question. How do I allocate a page from highmem, that's still within 32 bits? x86_64 has the DMA32 zone, but i386 has just HIGHMEM. As most devices can't DMA above 32 bit, I have 3 GB of memory that's not getting decent usage (or results in needless bouncing). What to do? I tried just enabling CONFIG_DMA32 for i386, but there is some guard against too many memory zones. I'm assuming this is there for a good reason? --=20 -- Pierre Ossman Linux kernel, MMC maintainer http://www.kernel.org rdesktop, core developer http://www.rdesktop.org WARNING: This correspondence is being monitored by the Swedish government. Make sure your server uses encryption for SMTP traffic and consider using PGP for end-to-end encryption. --=_freyr.drzeus.cx-10147-1214848374-0001-2 Content-Type: application/pgp-signature; name="signature.asc" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEARECAAYFAkhpH/EACgkQ7b8eESbyJLj7XQCgl6dThmKpkBEYOHfHkQfZmL1R NGUAn2yb6QHeq9lLk/w+HJUIIM5afRJ/ =cOPe -----END PGP SIGNATURE----- --=_freyr.drzeus.cx-10147-1214848374-0001-2-- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org