From: FUJITA Tomonori <tomof@xxxxxxx> Subject: RE: [PATCH 3/3] mptsas: add SMP passthrough support via bsg Date: Fri, 27 Jul 2007 02:09:05 +0900 > Use-space applications can put four memory addresses in the bsg (sg > v4) interface: request, response, dout_xferp, and din_xferp. > > For scsi commands, we use: > > request -> pointer to a scsi command (cmdp in sgv3) > response -> pointer to a sense buffer (sbp in sgv3) > dout_xferp -> pointer to out data > din_xferp -> pointer to in data > > For smp request/response, we use: > > request -> not used > response -> not used > dout_xferp -> pointer to a smp request frame > din_xferp -> pointer to a smp response frame > > > So we could use response field to send vendor's unique response to > user space. > > bsg wrongly assues the response field is used for sense buffer so the > maxium length is SCSI_SENSE_BUFFERSIZE, 96 bytes. I think that it's a > bit small for mpt's unique response. But, I'll fix the length > limitation bug soon. Oops, 96 bytes is large enough for mpt's unique response. Right? - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
