dahdi: Take a reference count on module when operating on spans directly.

Normally, spans are accessed via channels, which increment the reference
count on the supporting module as part of the open call.  When operating
on spans by number we are susceptible to a module_unload while we are
accessing the span.

Renames find_span to span_find_and_get to indicate that we're both
finding the span by number and increasing the reference count on the
span.  Spans themselves don't currently have reference counts, but we
can increment the reference count on the module that owns the spans.
This will prevent the module that has the span from unloading in the
middle of a span_config call, which in the case of the wcte12xp can take
awhile since the VPM firmware is loading.

Hopefully in the near future the spans themselves will be reference
counted directly.

Signed-off-by: Shaun Ruffell <sruffell@digium.com>
Acked-by: Kinsey Moore <kmoore@digium.com>

git-svn-id: http://svn.asterisk.org/svn/dahdi/linux/trunk@9583 a0bf4364-ded3-4de4-8d8a-66a801d63aff

0 files changed, 0 insertions, 0 deletions