diff options
| author | Julian Wiedmann <jwi@linux.ibm.com> | 2019-12-05 14:33:04 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-12-05 12:25:05 -0800 |
| commit | f9e50b02a99c3ebbaa30690e8d5be28a5c2624eb (patch) | |
| tree | d62bad662fb722988ad846fb5b04940eca4ecef9 /drivers/s390/net/qeth_core.h | |
| parent | f677fcb9aeb60c523ee36c1061ef2249b558d1b5 (diff) | |
s390/qeth: fix dangling IO buffers after halt/clear
The cio layer's intparm logic does not align itself well with how qeth
manages cmd IOs. When an active IO gets terminated via halt/clear, the
corresponding IRQ's intparm does not reflect the cmd buffer but rather
the intparm that was passed to ccw_device_halt() / ccw_device_clear().
This behaviour was recently clarified in
commit b91d9e67e50b ("s390/cio: fix intparm documentation").
As a result, qeth_irq() currently doesn't cancel a cmd that was
terminated via halt/clear. This primarily causes us to leak
card->read_cmd after the qeth device is removed, since our IO path still
holds a refcount for this cmd.
For qeth this means that we need to keep track of which IO is pending on
a device ('active_cmd'), and use this as the intparm when calling
halt/clear. Otherwise qeth_irq() can't match the subsequent IRQ to its
cmd buffer.
Since we now keep track of the _expected_ intparm, we can also detect
any mismatch; this would constitute a bug somewhere in the lower layers.
In this case cancel the active cmd - we effectively "lost" the IRQ and
should not expect any further notification for this IO.
Fixes: 405548959cc7 ("s390/qeth: add support for dynamically allocated cmds")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/s390/net/qeth_core.h')
| -rw-r--r-- | drivers/s390/net/qeth_core.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h index 7cdebd2e329f..871d44746f5c 100644 --- a/drivers/s390/net/qeth_core.h +++ b/drivers/s390/net/qeth_core.h @@ -628,6 +628,7 @@ struct qeth_ipato { struct qeth_channel { struct ccw_device *ccwdev; + struct qeth_cmd_buffer *active_cmd; enum qeth_channel_states state; atomic_t irq_pending; }; @@ -1038,6 +1039,8 @@ int qeth_do_run_thread(struct qeth_card *, unsigned long); void qeth_clear_thread_start_bit(struct qeth_card *, unsigned long); void qeth_clear_thread_running_bit(struct qeth_card *, unsigned long); int qeth_core_hardsetup_card(struct qeth_card *card, bool *carrier_ok); +int qeth_stop_channel(struct qeth_channel *channel); + void qeth_print_status_message(struct qeth_card *); int qeth_init_qdio_queues(struct qeth_card *); int qeth_send_ipa_cmd(struct qeth_card *, struct qeth_cmd_buffer *, |