This patch introduces special handling of the IUCV HVC console device.
If the first IUCV HVC terminal is used as (preferred) Linux console, and
needs some special handling for hangup.
The hvc_iucv_private structure contains a flag to indicate whether a IUCV
HVC device is used as a console.
A terminal acting as "console" behaves different if a tty hangup occurs:
If the iucv communication path is severed, a tty hangup is not
triggered (because the HVC layer does not notify its back-end in that case).
Instead, the console session is left unchanged and the IUCV HVC device is
reset to allow re-connects.
Note: Any output between the disconnect and a re-connect is discarded.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The console_initcall() order might pick up the hvc_iucv device as preferred
console even if it is not yet initialized.
Move HVC console instantiation to hvc_iucv_init() and cleanup device driver
initialization.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Update documentation of functions.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces a send buffer to limit outgoing IUCV messages up to
a maximum of 25 IUCV messages per second.
If no communication path to a IUCV HVC terminal exist, any data written to
the terminal is discarded.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The patch renames the IUCV application ID from "ihvc" to "lnxhvc".
The device driver allocates one IUCV terminal device (lnxhvc0) as default.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch introduces a new hypervisor console (HVC) back-end that provides
terminal access over the z/VM inter-user communication vehicle (IUCV).
The z/VM IUCV communication is independent of the regular tcp/ip network
and allows access even if there is no network connection between two
z/VM guest virtual machines.
The z/VM IUCV hypervisor console back-end helps the user to access a
z/VM guest virtual machine that lacks of network connectivity; and thus,
provides a "full-screen" terminal alternative to 3215/3270 terminal sessions.
Use the hvc_iucv=[0..8] kernel boot parameter to specify the number of
HVC terminals using a z/VM IUCV back-end.
A recent version of the s390-tools package is required to establish a
terminal connection to a z/VM IUCV hypervisor console back-end.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
