Adding support on the tx DMA path to allow recovery of errors when DMA responds with error status and abort all the subsequent ops. Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> --- drivers/ntb/ntb_transport.c | 119 ++++++++++++++++++++++++++++++++----------- 1 file changed, 88 insertions(+), 31 deletions(-) diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index 2ef9d913..bdb2001 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -102,6 +102,10 @@ struct ntb_queue_entry { void *buf; unsigned int len; unsigned int flags; + struct dma_async_tx_descriptor *txd; + int retries; + int errors; + unsigned int tx_index; struct ntb_transport_qp *qp; union { @@ -258,6 +262,9 @@ enum { static void ntb_transport_rxc_db(unsigned long data); static const struct ntb_ctx_ops ntb_transport_ops; static struct ntb_client ntb_transport_client; +static int ntb_async_tx_submit(struct ntb_transport_qp *qp, + struct ntb_queue_entry *entry); +static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset); static int ntb_transport_bus_match(struct device *dev, struct device_driver *drv) @@ -1444,6 +1451,33 @@ static void ntb_tx_copy_callback(void *data) struct ntb_queue_entry *entry = data; struct ntb_transport_qp *qp = entry->qp; struct ntb_payload_header __iomem *hdr = entry->tx_hdr; + struct dma_async_tx_descriptor *txd; + + txd = entry->txd; + + /* we need to check DMA results if we are using DMA */ + if (txd) { + switch (txd->result) { + case ERR_DMA_READ: + case ERR_DMA_WRITE: + entry->errors++; + case ERR_DMA_ABORT: + { + void __iomem *offset = + qp->tx_mw + qp->tx_max_frame * + entry->tx_index; + + /* resubmit via CPU */ + ntb_memcpy_tx(entry, offset); + qp->tx_memcpy++; + return; + } + + case ERR_DMA_NONE: + default: + break; + } + } iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags); @@ -1482,37 +1516,21 @@ static void ntb_memcpy_tx(struct ntb_queue_entry *entry, void __iomem *offset) ntb_tx_copy_callback(entry); } -static void ntb_async_tx(struct ntb_transport_qp *qp, - struct ntb_queue_entry *entry) +static int ntb_async_tx_submit(struct ntb_transport_qp *qp, + struct ntb_queue_entry *entry) { - struct ntb_payload_header __iomem *hdr; - struct dma_async_tx_descriptor *txd; struct dma_chan *chan = qp->tx_dma_chan; struct dma_device *device; + size_t len = entry->len; + void *buf = entry->buf; size_t dest_off, buff_off; struct dmaengine_unmap_data *unmap; dma_addr_t dest; dma_cookie_t cookie; - void __iomem *offset; - size_t len = entry->len; - void *buf = entry->buf; int retries = 0; - offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index; - hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); - entry->tx_hdr = hdr; - - iowrite32(entry->len, &hdr->len); - iowrite32((u32)qp->tx_pkts, &hdr->ver); - - if (!chan) - goto err; - - if (len < copy_bytes) - goto err; - device = chan->device; - dest = qp->tx_mw_phys + qp->tx_max_frame * qp->tx_index; + dest = qp->tx_mw_phys + qp->tx_max_frame * entry->tx_index; buff_off = (size_t)buf & ~PAGE_MASK; dest_off = (size_t)dest & ~PAGE_MASK; @@ -1532,39 +1550,74 @@ static void ntb_async_tx(struct ntb_transport_qp *qp, unmap->to_cnt = 1; for (retries = 0; retries < DMA_RETRIES; retries++) { - txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], - len, DMA_PREP_INTERRUPT); - if (txd) + entry->txd = device->device_prep_dma_memcpy(chan, dest, + unmap->addr[0], len, + DMA_PREP_INTERRUPT); + if (entry->txd) break; set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(DMA_OUT_RESOURCE_TO); } - if (!txd) { + if (!entry->txd) { qp->dma_tx_prep_err++; goto err_get_unmap; } - txd->callback = ntb_tx_copy_callback; - txd->callback_param = entry; - dma_set_unmap(txd, unmap); + entry->txd->callback = ntb_tx_copy_callback; + entry->txd->callback_param = entry; + dma_set_unmap(entry->txd, unmap); - cookie = dmaengine_submit(txd); + cookie = dmaengine_submit(entry->txd); if (dma_submit_error(cookie)) goto err_set_unmap; dmaengine_unmap_put(unmap); dma_async_issue_pending(chan); - qp->tx_async++; - return; + return 0; err_set_unmap: dmaengine_unmap_put(unmap); err_get_unmap: dmaengine_unmap_put(unmap); err: + return -ENXIO; +} + +static void ntb_async_tx(struct ntb_transport_qp *qp, + struct ntb_queue_entry *entry) +{ + struct ntb_payload_header __iomem *hdr; + struct dma_chan *chan = qp->tx_dma_chan; + void __iomem *offset; + int res; + + entry->tx_index = qp->tx_index; + offset = qp->tx_mw + qp->tx_max_frame * entry->tx_index; + hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header); + entry->tx_hdr = hdr; + + iowrite32(entry->len, &hdr->len); + iowrite32((u32)qp->tx_pkts, &hdr->ver); + + if (!chan) + goto err; + + if (entry->len < copy_bytes) + goto err; + + res = ntb_async_tx_submit(qp, entry); + if (res < 0) + goto err; + + if (!entry->retries) + qp->tx_async++; + + return; + +err: ntb_memcpy_tx(entry, offset); qp->tx_memcpy++; } @@ -1940,6 +1993,10 @@ int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, entry->buf = data; entry->len = len; entry->flags = 0; + entry->errors = 0; + entry->retries = 0; + entry->tx_index = 0; + entry->txd = NULL; rc = ntb_process_tx(qp, entry); if (rc) -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html