Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 5 Jul 2001 08:37:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 5 Jul 2001 08:36:56 -0400 Received: from [202.140.153.5] ([202.140.153.5]:20997 "EHLO techctd.techmas.hcltech.com") by vger.kernel.org with ESMTP id ; Thu, 5 Jul 2001 08:36:44 -0400 Message-ID: <3B445FA5.8CB55F45@techmas.hcltech.com> Date: Thu, 05 Jul 2001 18:07:57 +0530 From: Vasu Varma P V Organization: HCL Technologies X-Mailer: Mozilla 4.7 [en] (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: arjanv@redhat.com CC: linux-kernel@vger.kernel.org Subject: Re: DMA memory limitation? In-Reply-To: <3B4453E6.F4342781@techmas.hcltech.com> <3B44558A.B52B5C60@redhat.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org but we have a macro in include/asm-i386/dma.h, MAX_DMA_ADDRESS (PAGE_OFFSET+0x1000000). if i change it to a higher value, i am able to get more dma memory. Is there any way i can change this without compiling the kernel? Arjan van de Ven wrote: > Vasu Varma P V wrote: > > > > Hi, > > > > Is there any limitation on DMA memory we can allocate using > > kmalloc(size, GFP_DMA)? I am not able to acquire more than > > 14MB of the mem using this on my PCI SMP box with 256MB ram. > > I think there is restriction on ISA boards of 16MB. > > Can we increase it ? > > Why? > YOu don't have to allocate GFP_DMA memory for PCI cards! > GFP_DMA is for ISA cards only - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/