From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aleksey Gorelov Subject: Re: Generic Disk Driver in Linux Date: Thu, 24 Aug 2006 15:27:27 -0700 (PDT) Message-ID: <20060824222727.67706.qmail@web83111.mail.mud.yahoo.com> References: <44EE0DDA.5060600@cfl.rr.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <44EE0DDA.5060600@cfl.rr.com> Sender: linux-newbie-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii" To: Phillip Susi Cc: arjan@infradead.org, jengelh@linux01.gwdg.de, daniel.rodrick@gmail.com, linux-kernel@vger.kernel.org, kernelnewbies@nl.linux.org, linux-newbie@vger.kernel.org, satinder.jeet@gmail.com --- Phillip Susi wrote: > The int 13 calls to the bios can only accept addresses within the first > 1 MB of memory, and the calls are synchronous, so DMA really doesn't > matter as the cpu will be busy waiting anyhow while the IO takes place, > which will wreak all kinds of hell on the rest of the running system, > including other hardware ISRs. > Not that easy. Once you start int13 transfer, your vm86 thread may be preempted to allow cpu doing something useful, including other ISRs processing. - To unsubscribe from this list: send the line "unsubscribe linux-newbie" 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.linux-learn.org/faqs