Hi, On Mon, Jul 12, 2010 at 10:47 AM, David Zeuthen <davidz@xxxxxxxxxx> wrote: > On Mon, 2010-07-12 at 11:07 +0200, Kay Sievers wrote: >> On Wed, Jul 7, 2010 at 16:55, Hannes Reinecke <hare@xxxxxxx> wrote: >> > >> > SAS devices should be referenced by the SAS address of the target; >> > on the initiator side we assume an identity mapping between SAS >> > addresses and PCI devnumber. >> > SATA devices have an identity mapping between SATA links and >> > linux scsi_host structures, so we can map the host number onto >> > the SATA link. >> > For this to work the LUN numbering needs to be updated, too, >> > as SATA devices do not have the concept of a LUN, whereas normal >> > SCSI devices have. >> >> David, any chance to give this a try on your SAS box, and see if this >> works as expected for you too? > > Sure, will do later this week - it's currently powered off and in a > moving box! OK, I get these additional links in /dev/disk/by-path +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f362-lun-0x0000000000000000 -> ../../sds +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f363-lun-0x0000000000000000 -> ../../sdr +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f442-lun-0x0000000000000000 -> ../../sdq +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f443-lun-0x0000000000000000 -> ../../sdp +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f522-lun-0x0000000000000000 -> ../../sdo +│ ├── pci-0000:06:00.0-sas-0x500000e01b83f523-lun-0x0000000000000000 -> ../../sdn +│ ├── pci-0000:06:00.0-sas-0x500000e01b843d92-lun-0x0000000000000000 -> ../../sdm +│ └── pci-0000:06:00.0-sas-0x500000e01b843d93-lun-0x0000000000000000 -> ../../sdl for four SAS disks with two paths each. Btw, the WWN used is apparently not that of the actual disk # udevadm info -q all -n /dev/sdn|grep ID_WWN= E: ID_WWN=0x500000e01b83f520 which matches what is printed on the actual disk http://people.freedesktop.org/~david/FUJITSU-MAY2036RC-sas-disk-picture.jpg however the WWNs that your patch introduces differ from this. However those WWNs appear here # smp_discover /dev/bsg/expander-7\:0 --multiple |grep b83f52 phy 4:T:attached:[500000e01b83f523:01 t(SSP)] 3 Gbps # smp_discover /dev/bsg/expander-7\:1 --multiple |grep b83f52 phy 4:T:attached:[500000e01b83f522:00 t(SSP)] 3 Gbps e.g. the WWNs that you use are the WWNs of the actual ports, not the LUN itself, yes? You should probably use the LUN WWN instead. I mean, I think people are interested in the WWN of the LUN and they don't care so much about the WWN of the ports. Or maybe we want both? Anyway, I *think* that's the way it works but I could be wrong on some of the SAS details. FWIW, I've included sg_inq(8) output in [1] for both paths to the disk. David [1] : # sg_inq /dev/sdo --page 0x83 VPD INQUIRY: Device Identification page Designation descriptor number 1, descriptor length: 12 designator_type: NAA, code_set: Binary associated with the addressed logical unit NAA 5, IEEE Company_id: 0xe Vendor Specific Identifier: 0x1b83f520 [0x500000e01b83f520] Designation descriptor number 2, descriptor length: 12 transport: Serial Attached SCSI (SAS) designator_type: NAA, code_set: Binary associated with the target port NAA 5, IEEE Company_id: 0xe Vendor Specific Identifier: 0x1b83f522 [0x500000e01b83f522] Designation descriptor number 3, descriptor length: 8 transport: Serial Attached SCSI (SAS) designator_type: Relative target port, code_set: Binary associated with the target port Relative target port: 0x1 Designation descriptor number 4, descriptor length: 28 designator_type: SCSI name string, code_set: UTF-8 associated with the target device that contains addressed lu SCSI name string: naa.500000E01B83F520 # sg_inq /dev/sdn --page 0x83 VPD INQUIRY: Device Identification page Designation descriptor number 1, descriptor length: 12 designator_type: NAA, code_set: Binary associated with the addressed logical unit NAA 5, IEEE Company_id: 0xe Vendor Specific Identifier: 0x1b83f520 [0x500000e01b83f520] Designation descriptor number 2, descriptor length: 12 transport: Serial Attached SCSI (SAS) designator_type: NAA, code_set: Binary associated with the target port NAA 5, IEEE Company_id: 0xe Vendor Specific Identifier: 0x1b83f523 [0x500000e01b83f523] Designation descriptor number 3, descriptor length: 8 transport: Serial Attached SCSI (SAS) designator_type: Relative target port, code_set: Binary associated with the target port Relative target port: 0x2 Designation descriptor number 4, descriptor length: 28 designator_type: SCSI name string, code_set: UTF-8 associated with the target device that contains addressed lu SCSI name string: naa.500000E01B83F520 -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
