di_path_client_next_path

, di_path_phci_next_path

- libdevinfo path node traversal functions

Synopsis

cc [ flag... ] file... -ldevinfo [ library... ]
#include <libdevinfo.h>

di_path_t di_path_client_next_path(di_node_t node node,
     di_path_t path);

di_path_t di_path_phci_next_path(di_node_t node node,
     di_path_t path);

Parameters

node

The handle to a device node in a di_init(3DEVINFO) snapshot. For di_path_client_next_path(), node must be a client device node. For di_path_phci_next_path(), node must be a pHCI device node.

path

DI_PATH_NIL, or the handle to a path node in a snapshot.

Description

Each path node is an element in a pHCI-client matrix. The matrix is implemented by dual linked lists: one list links path nodes related to a common client head, and the other links path nodes related to a common pHCI head.

The di_path_client_next_path() function is called on a multipathing 'client' device node, where a 'client' is the child of a vHCI device node, and is associated with a specific endpoint device identity (independent of physical paths). If the path argument is NULL, di_path_client_next_path() returns the first path node associated with the client. To walk all path nodes associated with a client, returned di_path_t values are fed back into di_path_client_next_path(), via the path argument, until a null path node is returned. For each path node, di_path_bus_addr(3DEVINFO) returns the pHCI child path node unit-address.

The di_path_phci_next_path() function is called on a multipathing pHCI device node. If the path argument is NULL, di_path_phci_next_path() returns the first path node associated with the pHCI. To walk all path nodes associated with a pHCI, returned di_path_t values are fed back into di_path_phci_next_path(), via the path argument, until a null path node is returned. For each path node, di_path_client_node(3DEVINFO) provides a pointer to the associated client device node.

A device node can be a client device node of one multipathing class and a pHCI device node of another class.

Return Values

Upon successful completion, a handle to the next path node is returned. Otherwise, DI_PATH_NIL is returned and errno is set to indicate the error.

Errors

These functions will fail if:

EINVAL

One or more argument was invalid.

ENOTSUP

Path node information is not available in the snapshot.

ENXIO

The end of the path node list was reached.

Attributes

See attributes(5) for descriptions of the following attributes:

See Also

di_init(3DEVINFO), di_path_bus_addr(3DEVINFO), di_path_client_node(3DEVINFO), libdevinfo(3LIB), attributes(5)

Writing Device Drivers