From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: [PATCH 1/2] libiscsi, iser: Adjust data_length to include protection information Date: Tue, 03 Jun 2014 18:18:58 -0400 Message-ID: References: <1401639581-20111-1-git-send-email-sagig@mellanox.com> <1401639581-20111-2-git-send-email-sagig@mellanox.com> <538DF27F.50903@cs.wisc.edu> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <538DF27F.50903-hcNo3dDEHLuVc3sceRu5cw@public.gmane.org> (Mike Christie's message of "Tue, 03 Jun 2014 11:06:23 -0500") Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mike Christie Cc: Sagi Grimberg , nab-IzHhD5pYlfBP7FQvKIMDCQ@public.gmane.org, linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, target-devel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, oren-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org List-Id: linux-rdma@vger.kernel.org >>>>> "Mike" == Mike Christie writes: Mike> On 06/01/2014 11:19 AM, Sagi Grimberg wrote: >> >> +/* >> + * data integrity helpers >> + */ >> +static inline unsigned +iscsi_prot_len(unsigned data_len, unsigned >> sector_size) +{ >> + switch (sector_size) { >> + case 512: >> + return (data_len >> 9) * 8; >> + case 1024: >> + return (data_len >> 10) * 8; >> + case 2048: >> + return (data_len >> 11) * 8; >> + case 4096: >> + return (data_len >> 12) * 8; >> + default: >> + return (data_len >> ilog2(sector_size)) * 8; >> + } >> +} >> #endif Mike> I do not think this should not be in the iscsi code. In the data integrity update I posted there's a flag saying "transfer PI on the wire". That was meant to be the thing driver's should key off of to adjust transfer length. But I'm also happy to provide a unsigned int scsi_transfer_length(struct scsi_cmnd *) thingy that returns the right byte count. Just bear in mind that the host-facing DIX transfer length may be different. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html