Searched hist:"690 f6a1581c7c08e85451f62bcbfe40f29072842" (Results 1 – 3 of 3) sorted by relevance
| /openbmc/linux/drivers/s390/cio/ |
| H A D | vfio_ccw_private.h | diff 690f6a1581c7c08e85451f62bcbfe40f29072842 Tue Jan 29 09:13:57 CST 2019 Cornelia Huck <cohuck@redhat.com> vfio-ccw: rework ssch state handling
The flow for processing ssch requests can be improved by splitting
the BUSY state:
- CP_PROCESSING: We reject any user space requests while we are in
the process of translating a channel program and submitting it to
the hardware. Use -EAGAIN to signal user space that it should
retry the request.
- CP_PENDING: We have successfully submitted a request with ssch and
are now expecting an interrupt. As we can't handle more than one
channel program being processed, reject any further requests with
-EBUSY. A final interrupt will move us out of this state.
By making this a separate state, we make it possible to issue a
halt or a clear while we're still waiting for the final interrupt
for the ssch (in a follow-on patch).
It also makes a lot of sense not to preemptively filter out writes to
the io_region if we're in an incorrect state: the state machine will
handle this correctly.
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
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| H A D | vfio_ccw_fsm.c | diff 690f6a1581c7c08e85451f62bcbfe40f29072842 Tue Jan 29 09:13:57 CST 2019 Cornelia Huck <cohuck@redhat.com> vfio-ccw: rework ssch state handling
The flow for processing ssch requests can be improved by splitting
the BUSY state:
- CP_PROCESSING: We reject any user space requests while we are in
the process of translating a channel program and submitting it to
the hardware. Use -EAGAIN to signal user space that it should
retry the request.
- CP_PENDING: We have successfully submitted a request with ssch and
are now expecting an interrupt. As we can't handle more than one
channel program being processed, reject any further requests with
-EBUSY. A final interrupt will move us out of this state.
By making this a separate state, we make it possible to issue a
halt or a clear while we're still waiting for the final interrupt
for the ssch (in a follow-on patch).
It also makes a lot of sense not to preemptively filter out writes to
the io_region if we're in an incorrect state: the state machine will
handle this correctly.
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
|
| H A D | vfio_ccw_ops.c | diff 690f6a1581c7c08e85451f62bcbfe40f29072842 Tue Jan 29 09:13:57 CST 2019 Cornelia Huck <cohuck@redhat.com> vfio-ccw: rework ssch state handling
The flow for processing ssch requests can be improved by splitting
the BUSY state:
- CP_PROCESSING: We reject any user space requests while we are in
the process of translating a channel program and submitting it to
the hardware. Use -EAGAIN to signal user space that it should
retry the request.
- CP_PENDING: We have successfully submitted a request with ssch and
are now expecting an interrupt. As we can't handle more than one
channel program being processed, reject any further requests with
-EBUSY. A final interrupt will move us out of this state.
By making this a separate state, we make it possible to issue a
halt or a clear while we're still waiting for the final interrupt
for the ssch (in a follow-on patch).
It also makes a lot of sense not to preemptively filter out writes to
the io_region if we're in an incorrect state: the state machine will
handle this correctly.
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
|