James, VirtHBA project isn't aimed/positioned against the pvscsi effort. VirtHBA provides hypervisor independant interfaces at SCSI mid-layer(by some means- patch for released kernels or upstream if embraced), which hypervisors register and get notified appropriately. In addition, it also provides scsi emulation(target) capability at low layers. Thanks, --Siva On Thu, Mar 20, 2008 at 7:28 AM, James Smart <James.Smart@xxxxxxxxxx> wrote: > Siva, > > I'm curious to hear how you position this against the pvscsi effort > going on in the Xen world. > > -- james s > > > > Siva Kodiganti wrote: > > Hello Linux community, > > > > A Project page for Virt_HBA is created on source forge. > > https://sourceforge.net/projects/npivhba > > > > Project Virt_HBA is targeted for a providing patch for > > Linux kernels to provide set of scsi layer interfaces to > > aid Hypervisors in Linux to export Scsi Hosts to Guest > > VMs. Using these interfaces Hypervisors could export > > Scsi_Host of a virtual hba emulated by HBA hardware to > > Guest VMs. FC, and FCOE (may) have support for Nport > > Virtualization, a FW/HW mechanism to emulate multiple > > hbas(nports) using a single HBA HW. Qlogic, and > > Emulex have support for FC NPIV. With this mechanism, > > Hypervisor would be capable of mapping appropriate > > Guest VM's shost queuecommand to underlying NPIV host's > > queue_command, and other hostt relevant entry points(one > > to one mapping). This could also provide a means of > > security for luns exported through NPIV host to be > > visible for appropriate Guest OS, hiding from HostOS. > > > > Scsi Layer interfaces: > > > > Hypervisor's registration with scsi layer > > > > scsi_register_hypertt(xn_hostt, xsize); > > xsize is size of private structure maintained by > > hypervisor per npiv host. > > > > struct scsi_hyper_hostt xn_hostt { > > .hyp_module = "xn", > > .hyp_psize = size of( xhost); > > .hyp_alloc_vhost = xn_alloc_vhost, > > .hyp_add_vhost = xn_add_vhost, > > .hyp_remove_vhost = xn_remove_vhost, > > .hyp_trans_func = xn_trans_vhost, > > .hyp_async_notifier = xn_async_ntfr, > > .hyp_reboot_notifier = xn_reboot_ntfr, > > }; > > > > Scsi_Host { > > > > /* flag for FC or FCOE hw or fw hba virtulization */ > > unsigned virt_host:1; > > > > } > > > > scsi_alloc_host(), scsi_add_host(), and scsi_remove_host() > > interfaces notify registered hypervisor about FC/FCOE > > virtual Scsi_Host. scsi_alloc_host() would allocate private > > data area per scsi_host for registered hypervisors, which > > export to Guest VMs. > > > > Hypervisors uses these virtual hosts' lld driver hostt entry > > points to queue,abort,etc scsi commands to HBA driver directly > > bypassing Host BlK, SD layers. > > > > Thanks, > > Siva > > -- > > 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 > > > -- 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
