ldi_ev_notify(9F) Kernel Functions for Drivers ldi_ev_notify(9F)NAMEldi_ev_notify - propagate notification of a state change event
SYNOPSIS
#include <sys/sunldi.h>
int ldi_ev_notify(dev_info_t *dip, minor_t minor, int spec_type,
ldi_ev_cookie_t cookie, void *ev_data);
INTERFACE LEVEL
Solaris DDI specific (Solaris DDI)
PARAMETERS
dev_info_t *dip
The devinfo node of the layered consumer exporting the minor
device.
minor_t minor
The minor number of the exported minor device.
int spec_type
The type of minor device (S_IFCHR or S_IFBLK).
ldi_ev_cookie_t cookie
An opaque event cookie for the event type returned by a previous
call to ldi_ev_get_cookie(9F).
void *ev_data
Event specific data.
DESCRIPTION
The ldi_ev_notify() function propagates an event up the software stack.
It may result in two actions:
o Invocation of LDI callback handlers registered by layered
drivers up the software stack.
o Device contract events generated on minors exported to user‐
land.
The event propagated up the software stack may be different than the
event received by the layered driver invoking ldi_ev_notify(). For
example, a volume manager may receive an "offline" event on one of it's
LDI opened disks, but may choose to propagate a "degraded" event on
minors it exports to userland (since it may have more than one copy of
the data). The event cookie argument to ldi_ev_notify() may be differ‐
ent from the event cookie currently possessed by the layered driver. If
that is the case, the layered driver must generate another event cookie
via a new ldi_ev_get_cookie(9F) call.
Theldi_ev_* interfaces are designed to ensure that a "finalize" call is
generated for layered driver consumers at the earliest point where an
LDI_EV_FAILURE is detected. If this happens inside the LDI event frame‐
work, then the framework will invoke finalize. In the event a layered
driver detects/generates an LDI_EV_FAILURE, then the layered driver
must invoke ldi_ev_finalize(). The following is an example of a layered
driver invoking ldi_ev_finalize() for the "foo" event:
static int
widget_notify(ldi_handle_t lh, ldi_ev_cookie_t foo_cookie, void *arg,
void *ev_data)
{
ASSERT(strcmp(ldi_ev_get_type(foo_cookie), LDI_EV_FOO) == 0);
/* Map imported minors to exported minor */
widget_map(lh, &minor, &spec_type);
/*
* Call ldi_ev_notify() to propagate events to our consumers.
* This *must* happen before we check if widget should block
* foo
*/
if (ldi_ev_notify(dip, minor, spec_type, foo_cookie, ev_data)
!= LDI_EV_SUCCESS)
return (LDI_EV_FAILURE);
/*
* Next, check if we can allow the foo event
*/
if (widget_release(lh, LDI_EV_FOO) == WIDGET_SUCCESS) {
return (LDI_EV_SUCCESS)
}
/*
* We cannot permit the foo event. The first layer that detects
* failure i.e. us, must generate finalize events for *our*
* consumers
*/
ldi_ev_finalize(dip, minor, spec_type, LDI_EV_FAILURE,
foo_cookie, ev_data);
return (LDI_EV_FAILURE);
}
RETURN VALUES
The return values for this function are:
LDI_EV_SUCCESS
Consumers up the software stack permit state change.
LDI_EV_FAILURE
Consumers are blocking the state change.
CONTEXT
This function can be called from user and kernel context only.
SEE ALSOldi_ev_get_cookie(9F), ldi_ev_register_callbacks(9F),
ldi_ev_remove_callbacks(9F)SunOS 5.11 21 Aug 2007 ldi_ev_notify(9F)
