diff --git a/MAINTAINERS b/MAINTAINERS index 310da4295c70..030d8724b476 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7396,6 +7396,7 @@ NTB DRIVER CORE M: Jon Mason M: Dave Jiang M: Allen Hubbe +L: linux-ntb@googlegroups.com S: Supported W: https://github.com/jonmason/ntb/wiki T: git git://github.com/jonmason/ntb.git @@ -7407,6 +7408,7 @@ F: include/linux/ntb_transport.h NTB INTEL DRIVER M: Jon Mason M: Dave Jiang +L: linux-ntb@googlegroups.com S: Supported W: https://github.com/jonmason/ntb/wiki T: git git://github.com/jonmason/ntb.git diff --git a/drivers/net/ntb_netdev.c b/drivers/net/ntb_netdev.c index d8757bf9ad75..a9acf7156855 100644 --- a/drivers/net/ntb_netdev.c +++ b/drivers/net/ntb_netdev.c @@ -61,11 +61,21 @@ MODULE_VERSION(NTB_NETDEV_VER); MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Intel Corporation"); +/* Time in usecs for tx resource reaper */ +static unsigned int tx_time = 1; + +/* Number of descriptors to free before resuming tx */ +static unsigned int tx_start = 10; + +/* Number of descriptors still available before stop upper layer tx */ +static unsigned int tx_stop = 5; + struct ntb_netdev { struct list_head list; struct pci_dev *pdev; struct net_device *ndev; struct ntb_transport_qp *qp; + struct timer_list tx_timer; }; #define NTB_TX_TIMEOUT_MS 1000 @@ -136,11 +146,42 @@ static void ntb_netdev_rx_handler(struct ntb_transport_qp *qp, void *qp_data, } } +static int __ntb_netdev_maybe_stop_tx(struct net_device *netdev, + struct ntb_transport_qp *qp, int size) +{ + struct ntb_netdev *dev = netdev_priv(netdev); + + netif_stop_queue(netdev); + /* Make sure to see the latest value of ntb_transport_tx_free_entry() + * since the queue was last started. + */ + smp_mb(); + + if (likely(ntb_transport_tx_free_entry(qp) < size)) { + mod_timer(&dev->tx_timer, jiffies + usecs_to_jiffies(tx_time)); + return -EBUSY; + } + + netif_start_queue(netdev); + return 0; +} + +static int ntb_netdev_maybe_stop_tx(struct net_device *ndev, + struct ntb_transport_qp *qp, int size) +{ + if (netif_queue_stopped(ndev) || + (ntb_transport_tx_free_entry(qp) >= size)) + return 0; + + return __ntb_netdev_maybe_stop_tx(ndev, qp, size); +} + static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data, void *data, int len) { struct net_device *ndev = qp_data; struct sk_buff *skb; + struct ntb_netdev *dev = netdev_priv(ndev); skb = data; if (!skb || !ndev) @@ -155,6 +196,15 @@ static void ntb_netdev_tx_handler(struct ntb_transport_qp *qp, void *qp_data, } dev_kfree_skb(skb); + + if (ntb_transport_tx_free_entry(dev->qp) >= tx_start) { + /* Make sure anybody stopping the queue after this sees the new + * value of ntb_transport_tx_free_entry() + */ + smp_mb(); + if (netif_queue_stopped(ndev)) + netif_wake_queue(ndev); + } } static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb, @@ -163,10 +213,15 @@ static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb, struct ntb_netdev *dev = netdev_priv(ndev); int rc; + ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop); + rc = ntb_transport_tx_enqueue(dev->qp, skb, skb->data, skb->len); if (rc) goto err; + /* check for next submit */ + ntb_netdev_maybe_stop_tx(ndev, dev->qp, tx_stop); + return NETDEV_TX_OK; err: @@ -175,6 +230,23 @@ static netdev_tx_t ntb_netdev_start_xmit(struct sk_buff *skb, return NETDEV_TX_BUSY; } +static void ntb_netdev_tx_timer(unsigned long data) +{ + struct net_device *ndev = (struct net_device *)data; + struct ntb_netdev *dev = netdev_priv(ndev); + + if (ntb_transport_tx_free_entry(dev->qp) < tx_stop) { + mod_timer(&dev->tx_timer, jiffies + msecs_to_jiffies(tx_time)); + } else { + /* Make sure anybody stopping the queue after this sees the new + * value of ntb_transport_tx_free_entry() + */ + smp_mb(); + if (netif_queue_stopped(ndev)) + netif_wake_queue(ndev); + } +} + static int ntb_netdev_open(struct net_device *ndev) { struct ntb_netdev *dev = netdev_priv(ndev); @@ -197,8 +269,11 @@ static int ntb_netdev_open(struct net_device *ndev) } } + setup_timer(&dev->tx_timer, ntb_netdev_tx_timer, (unsigned long)ndev); + netif_carrier_off(ndev); ntb_transport_link_up(dev->qp); + netif_start_queue(ndev); return 0; @@ -219,6 +294,8 @@ static int ntb_netdev_close(struct net_device *ndev) while ((skb = ntb_transport_rx_remove(dev->qp, &len))) dev_kfree_skb(skb); + del_timer_sync(&dev->tx_timer); + return 0; } diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c index 87751cfd6f4f..865a3e3cc581 100644 --- a/drivers/ntb/hw/intel/ntb_hw_intel.c +++ b/drivers/ntb/hw/intel/ntb_hw_intel.c @@ -190,14 +190,17 @@ static inline int pdev_is_xeon(struct pci_dev *pdev) case PCI_DEVICE_ID_INTEL_NTB_SS_SNB: case PCI_DEVICE_ID_INTEL_NTB_SS_IVT: case PCI_DEVICE_ID_INTEL_NTB_SS_HSX: + case PCI_DEVICE_ID_INTEL_NTB_SS_BDX: case PCI_DEVICE_ID_INTEL_NTB_PS_JSF: case PCI_DEVICE_ID_INTEL_NTB_PS_SNB: case PCI_DEVICE_ID_INTEL_NTB_PS_IVT: case PCI_DEVICE_ID_INTEL_NTB_PS_HSX: + case PCI_DEVICE_ID_INTEL_NTB_PS_BDX: case PCI_DEVICE_ID_INTEL_NTB_B2B_JSF: case PCI_DEVICE_ID_INTEL_NTB_B2B_SNB: case PCI_DEVICE_ID_INTEL_NTB_B2B_IVT: case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX: + case PCI_DEVICE_ID_INTEL_NTB_B2B_BDX: return 1; } return 0; @@ -237,7 +240,7 @@ static inline int ndev_ignore_unsafe(struct intel_ntb_dev *ndev, static int ndev_mw_to_bar(struct intel_ntb_dev *ndev, int idx) { - if (idx < 0 || idx > ndev->mw_count) + if (idx < 0 || idx >= ndev->mw_count) return -EINVAL; return ndev->reg->mw_bar[idx]; } @@ -572,10 +575,13 @@ static ssize_t ndev_debugfs_read(struct file *filp, char __user *ubuf, "Connection Topology -\t%s\n", ntb_topo_string(ndev->ntb.topo)); - off += scnprintf(buf + off, buf_size - off, - "B2B Offset -\t\t%#lx\n", ndev->b2b_off); - off += scnprintf(buf + off, buf_size - off, - "B2B MW Idx -\t\t%d\n", ndev->b2b_idx); + if (ndev->b2b_idx != UINT_MAX) { + off += scnprintf(buf + off, buf_size - off, + "B2B MW Idx -\t\t%u\n", ndev->b2b_idx); + off += scnprintf(buf + off, buf_size - off, + "B2B Offset -\t\t%#lx\n", ndev->b2b_off); + } + off += scnprintf(buf + off, buf_size - off, "BAR4 Split -\t\t%s\n", ndev->bar4_split ? "yes" : "no"); @@ -1484,7 +1490,7 @@ static int xeon_setup_b2b_mw(struct intel_ntb_dev *ndev, pdev = ndev_pdev(ndev); mmio = ndev->self_mmio; - if (ndev->b2b_idx >= ndev->mw_count) { + if (ndev->b2b_idx == UINT_MAX) { dev_dbg(ndev_dev(ndev), "not using b2b mw\n"); b2b_bar = 0; ndev->b2b_off = 0; @@ -1776,6 +1782,13 @@ static int xeon_init_ntb(struct intel_ntb_dev *ndev) else ndev->b2b_idx = b2b_mw_idx; + if (ndev->b2b_idx >= ndev->mw_count) { + dev_dbg(ndev_dev(ndev), + "b2b_mw_idx %d invalid for mw_count %u\n", + b2b_mw_idx, ndev->mw_count); + return -EINVAL; + } + dev_dbg(ndev_dev(ndev), "setting up b2b mw idx %d means %d\n", b2b_mw_idx, ndev->b2b_idx); @@ -1843,6 +1856,9 @@ static int xeon_init_dev(struct intel_ntb_dev *ndev) case PCI_DEVICE_ID_INTEL_NTB_SS_HSX: case PCI_DEVICE_ID_INTEL_NTB_PS_HSX: case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX: + case PCI_DEVICE_ID_INTEL_NTB_SS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_PS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_B2B_BDX: ndev->hwerr_flags |= NTB_HWERR_SDOORBELL_LOCKUP; break; } @@ -1857,6 +1873,9 @@ static int xeon_init_dev(struct intel_ntb_dev *ndev) case PCI_DEVICE_ID_INTEL_NTB_SS_HSX: case PCI_DEVICE_ID_INTEL_NTB_PS_HSX: case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX: + case PCI_DEVICE_ID_INTEL_NTB_SS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_PS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_B2B_BDX: ndev->hwerr_flags |= NTB_HWERR_SB01BASE_LOCKUP; break; } @@ -1878,6 +1897,9 @@ static int xeon_init_dev(struct intel_ntb_dev *ndev) case PCI_DEVICE_ID_INTEL_NTB_SS_HSX: case PCI_DEVICE_ID_INTEL_NTB_PS_HSX: case PCI_DEVICE_ID_INTEL_NTB_B2B_HSX: + case PCI_DEVICE_ID_INTEL_NTB_SS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_PS_BDX: + case PCI_DEVICE_ID_INTEL_NTB_B2B_BDX: ndev->hwerr_flags |= NTB_HWERR_B2BDOORBELL_BIT14; break; } @@ -1996,7 +2018,7 @@ static inline void ndev_init_struct(struct intel_ntb_dev *ndev, ndev->ntb.ops = &intel_ntb_ops; ndev->b2b_off = 0; - ndev->b2b_idx = INT_MAX; + ndev->b2b_idx = UINT_MAX; ndev->bar4_split = 0; @@ -2234,14 +2256,17 @@ static const struct pci_device_id intel_ntb_pci_tbl[] = { {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_SNB)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_IVT)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_HSX)}, + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_B2B_BDX)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_JSF)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_SNB)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_IVT)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_HSX)}, + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_PS_BDX)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_JSF)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_SNB)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_IVT)}, {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_HSX)}, + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_NTB_SS_BDX)}, {0} }; MODULE_DEVICE_TABLE(pci, intel_ntb_pci_tbl); diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.h b/drivers/ntb/hw/intel/ntb_hw_intel.h index 7ddaf387b679..ea0612f797df 100644 --- a/drivers/ntb/hw/intel/ntb_hw_intel.h +++ b/drivers/ntb/hw/intel/ntb_hw_intel.h @@ -67,6 +67,9 @@ #define PCI_DEVICE_ID_INTEL_NTB_PS_HSX 0x2F0E #define PCI_DEVICE_ID_INTEL_NTB_SS_HSX 0x2F0F #define PCI_DEVICE_ID_INTEL_NTB_B2B_BWD 0x0C4E +#define PCI_DEVICE_ID_INTEL_NTB_B2B_BDX 0x6F0D +#define PCI_DEVICE_ID_INTEL_NTB_PS_BDX 0x6F0E +#define PCI_DEVICE_ID_INTEL_NTB_SS_BDX 0x6F0F /* Intel Xeon hardware */ diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index 1c6386d5f79c..6e3ee907d186 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -119,7 +119,8 @@ struct ntb_transport_qp { struct ntb_transport_ctx *transport; struct ntb_dev *ndev; void *cb_data; - struct dma_chan *dma_chan; + struct dma_chan *tx_dma_chan; + struct dma_chan *rx_dma_chan; bool client_ready; bool link_is_up; @@ -297,7 +298,7 @@ static LIST_HEAD(ntb_transport_list); static int ntb_bus_init(struct ntb_transport_ctx *nt) { - list_add(&nt->entry, &ntb_transport_list); + list_add_tail(&nt->entry, &ntb_transport_list); return 0; } @@ -452,7 +453,7 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, out_offset = 0; out_offset += snprintf(buf + out_offset, out_count - out_offset, - "NTB QP stats\n"); + "\nNTB QP stats:\n\n"); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_bytes - \t%llu\n", qp->rx_bytes); out_offset += snprintf(buf + out_offset, out_count - out_offset, @@ -470,11 +471,11 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_err_ver - \t%llu\n", qp->rx_err_ver); out_offset += snprintf(buf + out_offset, out_count - out_offset, - "rx_buff - \t%p\n", qp->rx_buff); + "rx_buff - \t0x%p\n", qp->rx_buff); out_offset += snprintf(buf + out_offset, out_count - out_offset, "rx_index - \t%u\n", qp->rx_index); out_offset += snprintf(buf + out_offset, out_count - out_offset, - "rx_max_entry - \t%u\n", qp->rx_max_entry); + "rx_max_entry - \t%u\n\n", qp->rx_max_entry); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_bytes - \t%llu\n", qp->tx_bytes); @@ -489,15 +490,32 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count, out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); out_offset += snprintf(buf + out_offset, out_count - out_offset, - "tx_mw - \t%p\n", qp->tx_mw); + "tx_mw - \t0x%p\n", qp->tx_mw); out_offset += snprintf(buf + out_offset, out_count - out_offset, - "tx_index - \t%u\n", qp->tx_index); + "tx_index (H) - \t%u\n", qp->tx_index); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "RRI (T) - \t%u\n", + qp->remote_rx_info->entry); out_offset += snprintf(buf + out_offset, out_count - out_offset, "tx_max_entry - \t%u\n", qp->tx_max_entry); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "free tx - \t%u\n", + ntb_transport_tx_free_entry(qp)); out_offset += snprintf(buf + out_offset, out_count - out_offset, - "\nQP Link %s\n", + "\n"); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "Using TX DMA - \t%s\n", + qp->tx_dma_chan ? "Yes" : "No"); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "Using RX DMA - \t%s\n", + qp->rx_dma_chan ? "Yes" : "No"); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "QP Link - \t%s\n", qp->link_is_up ? "Up" : "Down"); + out_offset += snprintf(buf + out_offset, out_count - out_offset, + "\n"); + if (out_offset > out_count) out_offset = out_count; @@ -535,6 +553,7 @@ static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock, } entry = list_first_entry(list, struct ntb_queue_entry, entry); list_del(&entry->entry); + out: spin_unlock_irqrestore(lock, flags); @@ -1206,7 +1225,7 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset) { struct dma_async_tx_descriptor *txd; struct ntb_transport_qp *qp = entry->qp; - struct dma_chan *chan = qp->dma_chan; + struct dma_chan *chan = qp->rx_dma_chan; struct dma_device *device; size_t pay_off, buff_off, len; struct dmaengine_unmap_data *unmap; @@ -1219,18 +1238,18 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset) goto err; if (len < copy_bytes) - goto err_wait; + goto err; device = chan->device; pay_off = (size_t)offset & ~PAGE_MASK; buff_off = (size_t)buf & ~PAGE_MASK; if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) - goto err_wait; + goto err; unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOWAIT); if (!unmap) - goto err_wait; + goto err; unmap->len = len; unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), @@ -1273,12 +1292,6 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset) dmaengine_unmap_put(unmap); err_get_unmap: dmaengine_unmap_put(unmap); -err_wait: - /* If the callbacks come out of order, the writing of the index to the - * last completed will be out of order. This may result in the - * receive stalling forever. - */ - dma_sync_wait(chan, qp->last_cookie); err: ntb_memcpy_rx(entry, offset); qp->rx_memcpy++; @@ -1373,8 +1386,8 @@ static void ntb_transport_rxc_db(unsigned long data) break; } - if (i && qp->dma_chan) - dma_async_issue_pending(qp->dma_chan); + if (i && qp->rx_dma_chan) + dma_async_issue_pending(qp->rx_dma_chan); if (i == qp->rx_max_entry) { /* there is more work to do */ @@ -1441,7 +1454,7 @@ static void ntb_async_tx(struct ntb_transport_qp *qp, { struct ntb_payload_header __iomem *hdr; struct dma_async_tx_descriptor *txd; - struct dma_chan *chan = qp->dma_chan; + struct dma_chan *chan = qp->tx_dma_chan; struct dma_device *device; size_t dest_off, buff_off; struct dmaengine_unmap_data *unmap; @@ -1634,14 +1647,27 @@ ntb_transport_create_queue(void *data, struct device *client_dev, dma_cap_set(DMA_MEMCPY, dma_mask); if (use_dma) { - qp->dma_chan = dma_request_channel(dma_mask, ntb_dma_filter_fn, - (void *)(unsigned long)node); - if (!qp->dma_chan) - dev_info(&pdev->dev, "Unable to allocate DMA channel\n"); + qp->tx_dma_chan = + dma_request_channel(dma_mask, ntb_dma_filter_fn, + (void *)(unsigned long)node); + if (!qp->tx_dma_chan) + dev_info(&pdev->dev, "Unable to allocate TX DMA channel\n"); + + qp->rx_dma_chan = + dma_request_channel(dma_mask, ntb_dma_filter_fn, + (void *)(unsigned long)node); + if (!qp->rx_dma_chan) + dev_info(&pdev->dev, "Unable to allocate RX DMA channel\n"); } else { - qp->dma_chan = NULL; + qp->tx_dma_chan = NULL; + qp->rx_dma_chan = NULL; } - dev_dbg(&pdev->dev, "Using %s memcpy\n", qp->dma_chan ? "DMA" : "CPU"); + + dev_dbg(&pdev->dev, "Using %s memcpy for TX\n", + qp->tx_dma_chan ? "DMA" : "CPU"); + + dev_dbg(&pdev->dev, "Using %s memcpy for RX\n", + qp->rx_dma_chan ? "DMA" : "CPU"); for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) { entry = kzalloc_node(sizeof(*entry), GFP_ATOMIC, node); @@ -1676,8 +1702,10 @@ ntb_transport_create_queue(void *data, struct device *client_dev, err1: while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q))) kfree(entry); - if (qp->dma_chan) - dma_release_channel(qp->dma_chan); + if (qp->tx_dma_chan) + dma_release_channel(qp->tx_dma_chan); + if (qp->rx_dma_chan) + dma_release_channel(qp->rx_dma_chan); nt->qp_bitmap_free |= qp_bit; err: return NULL; @@ -1701,12 +1729,27 @@ void ntb_transport_free_queue(struct ntb_transport_qp *qp) pdev = qp->ndev->pdev; - if (qp->dma_chan) { - struct dma_chan *chan = qp->dma_chan; + if (qp->tx_dma_chan) { + struct dma_chan *chan = qp->tx_dma_chan; /* Putting the dma_chan to NULL will force any new traffic to be * processed by the CPU instead of the DAM engine */ - qp->dma_chan = NULL; + qp->tx_dma_chan = NULL; + + /* Try to be nice and wait for any queued DMA engine + * transactions to process before smashing it with a rock + */ + dma_sync_wait(chan, qp->last_cookie); + dmaengine_terminate_all(chan); + dma_release_channel(chan); + } + + if (qp->rx_dma_chan) { + struct dma_chan *chan = qp->rx_dma_chan; + /* Putting the dma_chan to NULL will force any new traffic to be + * processed by the CPU instead of the DAM engine + */ + qp->rx_dma_chan = NULL; /* Try to be nice and wait for any queued DMA engine * transactions to process before smashing it with a rock @@ -1843,7 +1886,7 @@ int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q); if (!entry) { qp->tx_err_no_buf++; - return -ENOMEM; + return -EBUSY; } entry->cb_data = cb; @@ -1954,21 +1997,34 @@ EXPORT_SYMBOL_GPL(ntb_transport_qp_num); unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp) { unsigned int max; + unsigned int copy_align; if (!qp) return 0; - if (!qp->dma_chan) + if (!qp->tx_dma_chan && !qp->rx_dma_chan) return qp->tx_max_frame - sizeof(struct ntb_payload_header); + copy_align = max(qp->tx_dma_chan->device->copy_align, + qp->rx_dma_chan->device->copy_align); + /* If DMA engine usage is possible, try to find the max size for that */ max = qp->tx_max_frame - sizeof(struct ntb_payload_header); - max -= max % (1 << qp->dma_chan->device->copy_align); + max -= max % (1 << copy_align); return max; } EXPORT_SYMBOL_GPL(ntb_transport_max_size); +unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp) +{ + unsigned int head = qp->tx_index; + unsigned int tail = qp->remote_rx_info->entry; + + return tail > head ? tail - head : qp->tx_max_entry + tail - head; +} +EXPORT_SYMBOL_GPL(ntb_transport_tx_free_entry); + static void ntb_transport_doorbell_callback(void *data, int vector) { struct ntb_transport_ctx *nt = data; diff --git a/include/linux/ntb.h b/include/linux/ntb.h index b02f72bb8e32..f798e2afba88 100644 --- a/include/linux/ntb.h +++ b/include/linux/ntb.h @@ -522,10 +522,9 @@ static inline int ntb_mw_clear_trans(struct ntb_dev *ntb, int idx) * @speed: OUT - The link speed expressed as PCIe generation number. * @width: OUT - The link width expressed as the number of PCIe lanes. * - * Set the translation of a memory window. The peer may access local memory - * through the window starting at the address, up to the size. The address - * must be aligned to the alignment specified by ntb_mw_get_range(). The size - * must be aligned to the size alignment specified by ntb_mw_get_range(). + * Get the current state of the ntb link. It is recommended to query the link + * state once after every link event. It is safe to query the link state in + * the context of the link event callback. * * Return: One if the link is up, zero if the link is down, otherwise a * negative value indicating the error number. @@ -795,7 +794,7 @@ static inline int ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits) } /** - * ntb_peer_db_clear() - clear bits in the local doorbell register + * ntb_peer_db_clear() - clear bits in the peer doorbell register * @ntb: NTB device context. * @db_bits: Doorbell bits to clear. * diff --git a/include/linux/ntb_transport.h b/include/linux/ntb_transport.h index 2862861366a5..7243eb98a722 100644 --- a/include/linux/ntb_transport.h +++ b/include/linux/ntb_transport.h @@ -83,3 +83,4 @@ void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len); void ntb_transport_link_up(struct ntb_transport_qp *qp); void ntb_transport_link_down(struct ntb_transport_qp *qp); bool ntb_transport_link_query(struct ntb_transport_qp *qp); +unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp);