Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754308Ab2JBWeW (ORCPT ); Tue, 2 Oct 2012 18:34:22 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:23024 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753269Ab2JBWeU (ORCPT ); Tue, 2 Oct 2012 18:34:20 -0400 To: Kent Overstreet Cc: Zach Brown , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, tytso@google.com, tj@kernel.org, Dave Kleikamp , Dmitry Monakhov , "Maxim V. Patlasov" , michael.mesnier@intel.com, jeffrey.d.skirvin@intel.com, Martin Petersen Subject: Re: [RFC, PATCH] Extensible AIO interface From: "Martin K. Petersen" Organization: Oracle References: <20121001222341.GF26488@google.com> <20121001231222.GB14533@lenny.home.zabbo.net> <20121001232235.GH26488@google.com> Date: Tue, 02 Oct 2012 18:34:05 -0400 In-Reply-To: <20121001232235.GH26488@google.com> (Kent Overstreet's message of "Mon, 1 Oct 2012 16:22:35 -0700") Message-ID: User-Agent: Gnus/5.130005 (Ma Gnus v0.5) Emacs/24.0.97 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1039 Lines: 27 >>>>> "Kent" == Kent Overstreet writes: >> Hmm, careful here. I think that in DIF/DIX the checksums are >> per-sector, not per IO, right? That'd mean that the PAGE_SIZE attr >> limit in this patch would be magically creating different max IO size >> limits on different architectures. That doesn't seem great. Kent> Not just per sector, Per hardware sector. Per logical block (or for some devices less). Kent> For passing around checksums userspace would have to find out the Kent> hardware sector size and checksum type/size via a different Kent> interface, The relevant information is already exported in sysfs. Including the format, how many bytes of integrity metadata go with how many bytes of data, etc. -- Martin K. Petersen Oracle Linux Engineering -- 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/