hv_ata_pci_disengage(4) [freebsd man page]

HYPER-V(4)						   BSD Kernel Interfaces Manual 						HYPER-V(4)

NAME

     hv_ata_pci_disengage -- Hyper-V ATA PCI Disengage driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in the system kernel configuration file:

	   device hyperv

DESCRIPTION

     The hv_ata_pci_disengage driver prevents the native FreeBSD ATA driver from loading in the presence of Hyper-V.  FreeBSD guests running on
     Hyper-V can take advantage of the Hyper-V Storage Virtual Consumer (hv_storvsc(4)) for using their IDE devices.  Since the ATA driver serves
     IDE devices as well, there is a chance that the ATA driver may interfere with the operations of hv_storvsc(4).  The hv_ata_pci_disengage
     driver avoids conflicts between the ATA driver and hv_storvsc(4) by disabling the ATA driver when the FreeBSD guest is booting.

     A side effect of disabling the ATA driver is that CDROM may become inoperational on FreeBSD guest partitions.  If CDROM access is a must then
     users may use "set hw.ata.disk_enable=1" at boot time to prevent the ATA driver from being disabled.

SEE ALSO

     hv_netvsc(4), hv_storvsc(4), hv_utils(4), hv_vmbus(4)

HISTORY

     Support for hv_ata_pci_disengage first appeared in FreeBSD 10.0.  The driver was developed through a joint effort between Citrix Incorpo-
     rated, Microsoft Corporation, and Network Appliance Incorporated.

AUTHORS

     FreeBSD support for hv_ata_pci_disengage was first added by Microsoft BSD Integration Services Team <bsdic@microsoft.com>.

BSD
								September 10, 2013							       BSD

HYPER-V(4)						   BSD Kernel Interfaces Manual 						HYPER-V(4)

NAME

     hv_storvsc -- Hyper-V Storage Virtual Service Consumer

SYNOPSIS

     To compile this driver into the kernel, place the following lines in the system kernel configuration file:

	   device hyperv

DESCRIPTION

     The hv_storvsc driver implements the virtual store device for FreeBSD guest partitions running on Hyper-V.  FreeBSD guest partitions running
     on Hyper-V do not have direct access to storage devices attached to the Hyper-V server.  Although a FreeBSD guest can access storage devices
     using Hyper-V's full emulation mode, the performance in this mode tends to be unsatisfactory.

     To counter the above issues, the hv_storvsc driver implements a storage Virtual Service Consumer (VSC) that relays storage requests from the
     guest partition to the storage Virtual Service Provider (VSP) hosted in the root partition using the high performance data exchange infra-
     structure provided by hv_vmbus(4) driver.	The VSP in the root partition then forwards the storage related requests to the physical storage
     device.

     This driver functions by presenting a SCSI HBA interface to the Comman Access Method (CAM) layer.	CAM control blocks (CCBs) are converted
     into VSCSI protocol messages which are delivered to the root partition VSP over the Hyper-V VMBus.

SEE ALSO

     hv_ata_pci_disengage(4), hv_netvsc(4), hv_utils(4), hv_vmbus(4)

HISTORY

     Support for hv_storvsc first appeared in FreeBSD 10.0.  The driver was developed through a joint effort between Citrix Incorporated, Micro-
     soft Corporation, and Network Appliance Incorporated.

AUTHORS

     FreeBSD support for hv_storvsc was first added by Microsoft BSD Integration Services Team <bsdic@microsoft.com>.

BSD
								September 10, 2013							       BSD