diff options
Diffstat (limited to 'drivers/ntb')
-rw-r--r-- | drivers/ntb/ntb_transport.c | 169 |
1 files changed, 100 insertions, 69 deletions
diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c index efe3ad4..98e58c7 100644 --- a/drivers/ntb/ntb_transport.c +++ b/drivers/ntb/ntb_transport.c @@ -142,10 +142,11 @@ struct ntb_transport_qp { void (*rx_handler)(struct ntb_transport_qp *qp, void *qp_data, void *data, int len); + struct list_head rx_post_q; struct list_head rx_pend_q; struct list_head rx_free_q; - spinlock_t ntb_rx_pend_q_lock; - spinlock_t ntb_rx_free_q_lock; + /* ntb_rx_q_lock: synchronize access to rx_XXXX_q */ + spinlock_t ntb_rx_q_lock; void *rx_buff; unsigned int rx_index; unsigned int rx_max_entry; @@ -534,6 +535,27 @@ out: return entry; } +static struct ntb_queue_entry *ntb_list_mv(spinlock_t *lock, + struct list_head *list, + struct list_head *to_list) +{ + struct ntb_queue_entry *entry; + unsigned long flags; + + spin_lock_irqsave(lock, flags); + + if (list_empty(list)) { + entry = NULL; + } else { + entry = list_first_entry(list, struct ntb_queue_entry, entry); + list_move_tail(&entry->entry, to_list); + } + + spin_unlock_irqrestore(lock, flags); + + return entry; +} + static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt, unsigned int qp_num) { @@ -941,10 +963,10 @@ static int ntb_transport_init_queue(struct ntb_transport_ctx *nt, INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work); INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup_work); - spin_lock_init(&qp->ntb_rx_pend_q_lock); - spin_lock_init(&qp->ntb_rx_free_q_lock); + spin_lock_init(&qp->ntb_rx_q_lock); spin_lock_init(&qp->ntb_tx_free_q_lock); + INIT_LIST_HEAD(&qp->rx_post_q); INIT_LIST_HEAD(&qp->rx_pend_q); INIT_LIST_HEAD(&qp->rx_free_q); INIT_LIST_HEAD(&qp->tx_free_q); @@ -1107,22 +1129,47 @@ static void ntb_transport_free(struct ntb_client *self, struct ntb_dev *ndev) kfree(nt); } -static void ntb_rx_copy_callback(void *data) +static void ntb_complete_rxc(struct ntb_transport_qp *qp) { - struct ntb_queue_entry *entry = data; - struct ntb_transport_qp *qp = entry->qp; - void *cb_data = entry->cb_data; - unsigned int len = entry->len; - struct ntb_payload_header *hdr = entry->rx_hdr; + struct ntb_queue_entry *entry; + void *cb_data; + unsigned int len; + unsigned long irqflags; + + spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags); + + while (!list_empty(&qp->rx_post_q)) { + entry = list_first_entry(&qp->rx_post_q, + struct ntb_queue_entry, entry); + if (!(entry->flags & DESC_DONE_FLAG)) + break; + + entry->rx_hdr->flags = 0; + iowrite32(entry->index, &qp->rx_info->entry); + + cb_data = entry->cb_data; + len = entry->len; + + list_move_tail(&entry->entry, &qp->rx_free_q); - hdr->flags = 0; + spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags); - iowrite32(entry->index, &qp->rx_info->entry); + if (qp->rx_handler && qp->client_ready) + qp->rx_handler(qp, qp->cb_data, cb_data, len); - ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); + spin_lock_irqsave(&qp->ntb_rx_q_lock, irqflags); + } - if (qp->rx_handler && qp->client_ready) - qp->rx_handler(qp, qp->cb_data, cb_data, len); + spin_unlock_irqrestore(&qp->ntb_rx_q_lock, irqflags); +} + +static void ntb_rx_copy_callback(void *data) +{ + struct ntb_queue_entry *entry = data; + + entry->flags |= DESC_DONE_FLAG; + + ntb_complete_rxc(entry->qp); } static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) @@ -1138,19 +1185,18 @@ static void ntb_memcpy_rx(struct ntb_queue_entry *entry, void *offset) ntb_rx_copy_callback(entry); } -static void ntb_async_rx(struct ntb_queue_entry *entry, void *offset, - size_t len) +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_device *device; - size_t pay_off, buff_off; + size_t pay_off, buff_off, len; struct dmaengine_unmap_data *unmap; dma_cookie_t cookie; void *buf = entry->buf; - entry->len = len; + len = entry->len; if (!chan) goto err; @@ -1226,7 +1272,6 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) struct ntb_payload_header *hdr; struct ntb_queue_entry *entry; void *offset; - int rc; offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); @@ -1255,65 +1300,43 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) return -EIO; } - entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); + entry = ntb_list_mv(&qp->ntb_rx_q_lock, &qp->rx_pend_q, &qp->rx_post_q); if (!entry) { dev_dbg(&qp->ndev->pdev->dev, "no receive buffer\n"); qp->rx_err_no_buf++; - - rc = -ENOMEM; - goto err; + return -EAGAIN; } + entry->rx_hdr = hdr; + entry->index = qp->rx_index; + if (hdr->len > entry->len) { dev_dbg(&qp->ndev->pdev->dev, "receive buffer overflow! Wanted %d got %d\n", hdr->len, entry->len); qp->rx_err_oflow++; - rc = -EIO; - goto err; - } + entry->len = -EIO; + entry->flags |= DESC_DONE_FLAG; - dev_dbg(&qp->ndev->pdev->dev, - "RX OK index %u ver %u size %d into buf size %d\n", - qp->rx_index, hdr->ver, hdr->len, entry->len); + ntb_complete_rxc(qp); + } else { + dev_dbg(&qp->ndev->pdev->dev, + "RX OK index %u ver %u size %d into buf size %d\n", + qp->rx_index, hdr->ver, hdr->len, entry->len); - qp->rx_bytes += hdr->len; - qp->rx_pkts++; + qp->rx_bytes += hdr->len; + qp->rx_pkts++; - entry->index = qp->rx_index; - entry->rx_hdr = hdr; + entry->len = hdr->len; - ntb_async_rx(entry, offset, hdr->len); + ntb_async_rx(entry, offset); + } qp->rx_index++; qp->rx_index %= qp->rx_max_entry; return 0; - -err: - /* FIXME: if this syncrhonous update of the rx_index gets ahead of - * asyncrhonous ntb_rx_copy_callback of previous entry, there are three - * scenarios: - * - * 1) The peer might miss this update, but observe the update - * from the memcpy completion callback. In this case, the buffer will - * not be freed on the peer to be reused for a different packet. The - * successful rx of a later packet would clear the condition, but the - * condition could persist if several rx fail in a row. - * - * 2) The peer may observe this update before the asyncrhonous copy of - * prior packets is completed. The peer may overwrite the buffers of - * the prior packets before they are copied. - * - * 3) Both: the peer may observe the update, and then observe the index - * decrement by the asynchronous completion callback. Who knows what - * badness that will cause. - */ - hdr->flags = 0; - iowrite32(qp->rx_index, &qp->rx_info->entry); - - return rc; } static void ntb_transport_rxc_db(unsigned long data) @@ -1333,7 +1356,7 @@ static void ntb_transport_rxc_db(unsigned long data) break; } - if (qp->dma_chan) + if (i && qp->dma_chan) dma_async_issue_pending(qp->dma_chan); if (i == qp->rx_max_entry) { @@ -1609,7 +1632,7 @@ ntb_transport_create_queue(void *data, struct device *client_dev, goto err1; entry->qp = qp; - ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, + ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_free_q); } @@ -1634,7 +1657,7 @@ err2: while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q))) kfree(entry); err1: - while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) + 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); @@ -1689,11 +1712,16 @@ void ntb_transport_free_queue(struct ntb_transport_qp *qp) qp->tx_handler = NULL; qp->event_handler = NULL; - while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q))) + while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q))) kfree(entry); - while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) { - dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n"); + while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q))) { + dev_warn(&pdev->dev, "Freeing item from non-empty rx_pend_q\n"); + kfree(entry); + } + + while ((entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_post_q))) { + dev_warn(&pdev->dev, "Freeing item from non-empty rx_post_q\n"); kfree(entry); } @@ -1724,14 +1752,14 @@ void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len) if (!qp || qp->client_ready) return NULL; - entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q); + entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_pend_q); if (!entry) return NULL; buf = entry->cb_data; *len = entry->len; - ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q); + ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_free_q); return buf; } @@ -1757,15 +1785,18 @@ int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data, if (!qp) return -EINVAL; - entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q); + entry = ntb_list_rm(&qp->ntb_rx_q_lock, &qp->rx_free_q); if (!entry) return -ENOMEM; entry->cb_data = cb; entry->buf = data; entry->len = len; + entry->flags = 0; + + ntb_list_add(&qp->ntb_rx_q_lock, &entry->entry, &qp->rx_pend_q); - ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q); + tasklet_schedule(&qp->rxc_db_work); return 0; } |