te
Copyright (c) 2007, Sun Microsystems, Inc. All Rights Reserved.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
ddi_fm_handler_register, ddi_fm_handler_unregister - register or unregister an error handling callback

#include <sys/ddifm.h>

void ddi_fm_handler_register(dev_info_t *dip,
 ddi_err_func_t error_handler, void *impl_data);

void ddi_fm_handler_unregister(dev_info_t *dip);

illumos DDI specific (illumos DDI) dip error_handler impl_data The ddi_fm_handler_register() function registers an error handler callback routine with the I/O Fault Management framework. The error handler callback, error_handler, is called to process error conditions detected by the system. In addition to its device instance, dip, the error handler is called with a pointer to a fault management error status structure, ddi_fm_error_t. For example:

int (*ddi_err_func_t)(dev_info_t *dip, ddi_fm_error_t *error_status);

A driver error handling callback is passed the following arguments:

The primary responsibilities of the error handler include:

During the invocation of an error handler, a device driver might need to quiesce or suspend all I/O activities in order to check for error conditions or status in:

For each error detected, the driver must formulate and post an error report via ddi_fm_ereport_post() for problem analysis by the illumos Fault Manager fmd(8).

For a PCI, PCI/X, or PCI Express leaf device, the pci_ereport_post() function is provided to carry out reporting responsibilities on behalf of the driver. In many cases, an error handler callback function of the following form can be used:

xxx_err_cb(dev_info_t *dip, ddi_fm_error_t *errp) {
 pci_ereport_post(dip, errp, NULL);
 return (errp->fme_status);
}

In addition, the driver might be able to carry out further device specific checks within the error handler.

Error handlers can be called from kernel, interrupt, or high-level interrupt context. The interrupt block cookie returned from ddi_fm_init() should be used to allocate and initialize any synchronization variables and locks that might be used within the error handler callback function. Such locks may not be held by the driver when a device register is accessed with functions such as ddi_get8(9F) and ddi_put8(9F).

The data structure, ddi_fm_error_t, contains an FMA protocol (format 1) ENA for the current error propagation chain, the status of the error handler callback, an error expectation flag, and any potential access or DMA handles associated with an error detected by the parent nexus.

The ddi_fm_handler_unregister() function removes a previously registered error handling callback for the device instance specified by the dip.

The ddi_fm_handler_register() and ddi_fm_handler_unregister() functions must be called from kernel context in an attach(9E) or detach(9E) entry point. The registered error handler, error_handler, callback can be called from kernel, interrupt, or high level interrupt context. See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE

Interface Stability Committed

attributes (7), fmd (8), attach (9E), detach (9E), ddi_fm_ereport_post (9F), ddi_fm_init (9F), ddi_get8 (9F), ddi_put8 (9F), pci_ereport_post (9F), ddi_fm_error (9S)

Writing Device Drivers