From 7c47f5afdeef763599f1ae22d29b8c3904c58315 Mon Sep 17 00:00:00 2001 From: Julian Wiedmann Date: Fri, 23 Aug 2019 11:48:47 +0200 Subject: s390/qdio: enable drivers to poll for Output completions While commit d36deae75011 ("qdio: extend API to allow polling") enhanced the qdio layer so that drivers can poll their Input Queues, we don't have the corresponding infrastructure for Output Queues yet. Factor out a helper that scans a single QDIO Queue, so that qeth can implement TX NAPI on top of it. While doing so, remove the duplicated tracking of the next-to-scan index (q->first_to_check vs q->first_to_kick) in this code path. qdio_handle_aobs() needs to move slightly upwards in the code hierarchy, so that it's still called from the polling path. Signed-off-by: Julian Wiedmann Acked-by: Vasily Gorbik Signed-off-by: David S. Miller --- arch/s390/include/asm/qdio.h | 3 +++ drivers/s390/cio/qdio_main.c | 64 +++++++++++++++++++++++++++++--------------- 2 files changed, 46 insertions(+), 21 deletions(-) diff --git a/arch/s390/include/asm/qdio.h b/arch/s390/include/asm/qdio.h index f647d565bd6d..79b4a3e9dc5d 100644 --- a/arch/s390/include/asm/qdio.h +++ b/arch/s390/include/asm/qdio.h @@ -416,6 +416,9 @@ extern int do_QDIO(struct ccw_device *, unsigned int, int, unsigned int, extern int qdio_start_irq(struct ccw_device *, int); extern int qdio_stop_irq(struct ccw_device *, int); extern int qdio_get_next_buffers(struct ccw_device *, int, int *, int *); +extern int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, + bool is_input, unsigned int *bufnr, + unsigned int *error); extern int qdio_shutdown(struct ccw_device *, int); extern int qdio_free(struct ccw_device *); extern int qdio_get_ssqd_desc(struct ccw_device *, struct qdio_ssqd_desc *); diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c index 4142c85e77d8..5efba0d29190 100644 --- a/drivers/s390/cio/qdio_main.c +++ b/drivers/s390/cio/qdio_main.c @@ -647,8 +647,6 @@ static void qdio_kick_handler(struct qdio_q *q, unsigned int count) qperf_inc(q, outbound_handler); DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x", start, count); - if (q->u.out.use_cq) - qdio_handle_aobs(q, start, count); } q->handler(q->irq_ptr->cdev, q->qdio_error, q->nr, start, count, @@ -774,8 +772,11 @@ static inline int qdio_outbound_q_moved(struct qdio_q *q, unsigned int start) count = get_outbound_buffer_frontier(q, start); - if (count) + if (count) { DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out moved:%1d", q->nr); + if (q->u.out.use_cq) + qdio_handle_aobs(q, start, count); + } return count; } @@ -1655,6 +1656,44 @@ rescan: } EXPORT_SYMBOL(qdio_start_irq); +static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr, + unsigned int *error) +{ + unsigned int start = q->first_to_check; + int count; + + count = q->is_input_q ? qdio_inbound_q_moved(q, start) : + qdio_outbound_q_moved(q, start); + if (count == 0) + return 0; + + *bufnr = start; + *error = q->qdio_error; + + /* for the next time */ + q->first_to_check = add_buf(start, count); + q->qdio_error = 0; + + return count; +} + +int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input, + unsigned int *bufnr, unsigned int *error) +{ + struct qdio_irq *irq_ptr = cdev->private->qdio_data; + struct qdio_q *q; + + if (!irq_ptr) + return -ENODEV; + q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr]; + + if (need_siga_sync(q)) + qdio_siga_sync_q(q); + + return __qdio_inspect_queue(q, bufnr, error); +} +EXPORT_SYMBOL_GPL(qdio_inspect_queue); + /** * qdio_get_next_buffers - process input buffers * @cdev: associated ccw_device for the qdio subchannel @@ -1672,13 +1711,10 @@ int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr, { struct qdio_q *q; struct qdio_irq *irq_ptr = cdev->private->qdio_data; - unsigned int start; - int count; if (!irq_ptr) return -ENODEV; q = irq_ptr->input_qs[nr]; - start = q->first_to_check; /* * Cannot rely on automatic sync after interrupt since queues may @@ -1689,25 +1725,11 @@ int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr, qdio_check_outbound_pci_queues(irq_ptr); - count = qdio_inbound_q_moved(q, start); - if (count == 0) - return 0; - - start = add_buf(start, count); - q->first_to_check = start; - /* Note: upper-layer MUST stop processing immediately here ... */ if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)) return -EIO; - *bufnr = q->first_to_kick; - *error = q->qdio_error; - - /* for the next time */ - q->first_to_kick = add_buf(q->first_to_kick, count); - q->qdio_error = 0; - - return count; + return __qdio_inspect_queue(q, bufnr, error); } EXPORT_SYMBOL(qdio_get_next_buffers); -- cgit v1.2.3-59-g8ed1b