XenPvBlkDxe.c File Reference

#include "XenPvBlkDxe.h"
#include "BlockFront.h"

Go to the source code of this file.

Functions
EFI_STATUS EFIAPI	XenPvBlkDxeUnload (IN EFI_HANDLE ImageHandle)
EFI_STATUS EFIAPI	XenPvBlkDxeDriverEntryPoint (IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable)
EFI_STATUS EFIAPI	XenPvBlkDxeDriverBindingSupported (IN EFI_DRIVER_BINDING_PROTOCOL *This, IN EFI_HANDLE ControllerHandle, IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL)
EFI_STATUS EFIAPI	XenPvBlkDxeDriverBindingStart (IN EFI_DRIVER_BINDING_PROTOCOL *This, IN EFI_HANDLE ControllerHandle, IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL)
EFI_STATUS EFIAPI	XenPvBlkDxeDriverBindingStop (IN EFI_DRIVER_BINDING_PROTOCOL *This, IN EFI_HANDLE ControllerHandle, IN UINTN NumberOfChildren, IN EFI_HANDLE *ChildHandleBuffer OPTIONAL)

Variables
EFI_DRIVER_BINDING_PROTOCOL	gXenPvBlkDxeDriverBinding

Detailed Description

This driver produce a BlockIo protocol instance for a Xen PV block device.

This driver support XenBus protocol of type 'vbd'. Every function that comsume XenBus protocol are in BlockFront, which the implementation to access a Xen PV device. The BlockIo implementation is in it's one file and will call BlockFront functions.

Copyright (C) 2014, Citrix Ltd.

SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file XenPvBlkDxe.c.

Function Documentation

XenPvBlkDxeDriverBindingStart()

EFI_STATUS EFIAPI XenPvBlkDxeDriverBindingStart	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath	OPTIONAL
	)

Starts a device controller.

The Start() function is designed to be invoked from the EFI boot service ConnectController(). As a result, much of the error checking on the parameters to Start() has been moved into this common boot service. It is legal to call Start() from other locations, but the following calling restrictions must be followed, or the system behavior will not be deterministic.

1. ControllerHandle must be a valid EFI_HANDLE.
2. If RemainingDevicePath is not NULL, then it must be a pointer to a naturally aligned EFI_DEVICE_PATH_PROTOCOL.
3. Prior to calling Start(), the Supported() function for the driver specified by This must have been called with the same calling parameters, and Supported() must have returned EFI_SUCCESS.

Parameters

[in]	This	A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
[in]	ControllerHandle	The handle of the controller to start. This handle must support a protocol interface that supplies an I/O abstraction to the driver.
[in]	RemainingDevicePath	A pointer to the remaining portion of a device path. This parameter is ignored by device drivers, and is optional for bus drivers. For a bus driver, if this parameter is NULL, then handles for all the children of Controller are created by this driver. If this parameter is not NULL and the first Device Path Node is not the End of Device Path Node, then only the handle for the child device specified by the first Device Path Node of RemainingDevicePath is created by this driver. If the first Device Path Node of RemainingDevicePath is the End of Device Path Node, no child handle is created by this driver.

Return values

EFI_SUCCESS	The device was started.
EFI_DEVICE_ERROR	The device could not be started due to a device error.Currently not implemented.
EFI_OUT_OF_RESOURCES	The request could not be completed due to a lack of resources.
Others	The driver failed to start the device.

Definition at line 252 of file XenPvBlkDxe.c.

XenPvBlkDxeDriverBindingStop()

EFI_STATUS EFIAPI XenPvBlkDxeDriverBindingStop	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN UINTN	NumberOfChildren,
		IN EFI_HANDLE *ChildHandleBuffer	OPTIONAL
	)

Stops a device controller.

The Stop() function is designed to be invoked from the EFI boot service DisconnectController(). As a result, much of the error checking on the parameters to Stop() has been moved into this common boot service. It is legal to call Stop() from other locations, but the following calling restrictions must be followed, or the system behavior will not be deterministic.

1. ControllerHandle must be a valid EFI_HANDLE that was used on a previous call to this same driver's Start() function.
2. The first NumberOfChildren handles of ChildHandleBuffer must all be a valid EFI_HANDLE. In addition, all of these handles must have been created in this driver's Start() function, and the Start() function must have called OpenProtocol() on ControllerHandle with an Attribute of EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER.

Parameters

[in]	This	A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
[in]	ControllerHandle	A handle to the device being stopped. The handle must support a bus specific I/O protocol for the driver to use to stop the device.
[in]	NumberOfChildren	The number of child device handles in ChildHandleBuffer.
[in]	ChildHandleBuffer	An array of child handles to be freed. May be NULL if NumberOfChildren is 0.

Return values

EFI_SUCCESS	The device was stopped.
EFI_DEVICE_ERROR	The device could not be stopped due to a device error.

Definition at line 364 of file XenPvBlkDxe.c.

XenPvBlkDxeDriverBindingSupported()

EFI_STATUS EFIAPI XenPvBlkDxeDriverBindingSupported	(	IN EFI_DRIVER_BINDING_PROTOCOL *	This,
		IN EFI_HANDLE	ControllerHandle,
		IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath	OPTIONAL
	)

Tests to see if this driver supports a given controller. If a child device is provided, it further tests to see if this driver supports creating a handle for the specified child device.

This function checks to see if the driver specified by This supports the device specified by ControllerHandle. Drivers will typically use the device path attached to ControllerHandle and/or the services from the bus I/O abstraction attached to ControllerHandle to determine if the driver supports ControllerHandle. This function may be called many times during platform initialization. In order to reduce boot times, the tests performed by this function must be very small, and take as little time as possible to execute. This function must not change the state of any hardware devices, and this function must be aware that the device specified by ControllerHandle may already be managed by the same driver or a different driver. This function must match its calls to AllocatePages() with FreePages(), AllocatePool() with FreePool(), and OpenProtocol() with CloseProtocol(). Because ControllerHandle may have been previously started by the same driver, if a protocol is already in the opened state, then it must not be closed with CloseProtocol(). This is required to guarantee the state of ControllerHandle is not modified by this function.

Parameters

[in]	This	A pointer to the EFI_DRIVER_BINDING_PROTOCOL instance.
[in]	ControllerHandle	The handle of the controller to test. This handle must support a protocol interface that supplies an I/O abstraction to the driver.
[in]	RemainingDevicePath	A pointer to the remaining portion of a device path. This parameter is ignored by device drivers, and is optional for bus drivers. For bus drivers, if this parameter is not NULL, then the bus driver must determine if the bus controller specified by ControllerHandle and the child controller specified by RemainingDevicePath are both supported by this bus driver.

Return values

EFI_SUCCESS	The device specified by ControllerHandle and RemainingDevicePath is supported by the driver specified by This.
EFI_ALREADY_STARTED	The device specified by ControllerHandle and RemainingDevicePath is already being managed by the driver specified by This.
EFI_ACCESS_DENIED	The device specified by ControllerHandle and RemainingDevicePath is already being managed by a different driver or an application that requires exclusive access. Currently not implemented.
EFI_UNSUPPORTED	The device specified by ControllerHandle and RemainingDevicePath is not supported by the driver specified by This.

Definition at line 178 of file XenPvBlkDxe.c.

XenPvBlkDxeDriverEntryPoint()

EFI_STATUS EFIAPI XenPvBlkDxeDriverEntryPoint	(	IN EFI_HANDLE	ImageHandle,
		IN EFI_SYSTEM_TABLE *	SystemTable
	)

This is the declaration of an EFI image entry point. This entry point is the same for UEFI Applications, UEFI OS Loaders, and UEFI Drivers including both device drivers and bus drivers.

Parameters

ImageHandle	The firmware allocated handle for the UEFI image.
SystemTable	A pointer to the EFI System Table.

Return values

EFI_SUCCESS	The operation completed successfully.
Others	An unexpected error occurred.

Definition at line 111 of file XenPvBlkDxe.c.

XenPvBlkDxeUnload()

EFI_STATUS EFIAPI XenPvBlkDxeUnload

(

IN EFI_HANDLE

ImageHandle

)

Unloads an image.

Parameters

ImageHandle

Handle that identifies the image to be unloaded.

Return values

EFI_SUCCESS	The image has been unloaded.
EFI_INVALID_PARAMETER	ImageHandle is not a valid image handle.

Definition at line 42 of file XenPvBlkDxe.c.

Variable Documentation

gXenPvBlkDxeDriverBinding

EFI_DRIVER_BINDING_PROTOCOL gXenPvBlkDxeDriverBinding

Initial value:

= {
  XenPvBlkDxeDriverBindingSupported,
  XenPvBlkDxeDriverBindingStart,
  XenPvBlkDxeDriverBindingStop,
  XEN_PV_BLK_DXE_VERSION,
  NULL,
  NULL
}

Driver Binding Protocol instance

Definition at line 22 of file XenPvBlkDxe.c.