Merge tag 'ntb-3.13' of git://github.com/jonmason/ntb
authorLinus Torvalds <torvalds@linux-foundation.org>
Tue, 26 Nov 2013 19:15:12 +0000 (11:15 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 26 Nov 2013 19:15:12 +0000 (11:15 -0800)
Pull non-transparent bridge updates from Jon Mason:
 "NTB driver bug fixes to address a missed call to pci_enable_msix,
  NTB-RP Link Up issue, Xeon Doorbell errata workaround, ntb_transport
  link down race, and correct dmaengine_get/put usage.

  Also, clean-ups to remove duplicate defines and document a hardware
  errata.  Finally, some changes to improve performance"

* tag 'ntb-3.13' of git://github.com/jonmason/ntb:
  NTB: Disable interrupts and poll under high load
  NTB: Enable Snoop on Primary Side
  NTB: Document HW errata
  NTB: remove duplicate defines
  NTB: correct dmaengine_get/put usage
  NTB: Fix ntb_transport link down race
  ntb: Fix missed call to pci_enable_msix()
  NTB: Fix NTB-RP Link Up
  NTB: Xeon Doorbell errata workaround

drivers/ntb/ntb_hw.c
drivers/ntb/ntb_hw.h
drivers/ntb/ntb_regs.h
drivers/ntb/ntb_transport.c

index 1cb6e51e6bda97aadb4ba88bd46123544dcc4140..170e8e60cdb7fe3d47307d4b9146039e3af7f3a8 100644 (file)
@@ -141,6 +141,24 @@ void ntb_unregister_event_callback(struct ntb_device *ndev)
        ndev->event_cb = NULL;
 }
 
+static void ntb_irq_work(unsigned long data)
+{
+       struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data;
+       int rc;
+
+       rc = db_cb->callback(db_cb->data, db_cb->db_num);
+       if (rc)
+               tasklet_schedule(&db_cb->irq_work);
+       else {
+               struct ntb_device *ndev = db_cb->ndev;
+               unsigned long mask;
+
+               mask = readw(ndev->reg_ofs.ldb_mask);
+               clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+               writew(mask, ndev->reg_ofs.ldb_mask);
+       }
+}
+
 /**
  * ntb_register_db_callback() - register a callback for doorbell interrupt
  * @ndev: pointer to ntb_device instance
@@ -155,7 +173,7 @@ void ntb_unregister_event_callback(struct ntb_device *ndev)
  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
  */
 int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
-                            void *data, void (*func)(void *data, int db_num))
+                            void *data, int (*func)(void *data, int db_num))
 {
        unsigned long mask;
 
@@ -166,6 +184,10 @@ int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
 
        ndev->db_cb[idx].callback = func;
        ndev->db_cb[idx].data = data;
+       ndev->db_cb[idx].ndev = ndev;
+
+       tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work,
+                    (unsigned long) &ndev->db_cb[idx]);
 
        /* unmask interrupt */
        mask = readw(ndev->reg_ofs.ldb_mask);
@@ -194,6 +216,8 @@ void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx)
        set_bit(idx * ndev->bits_per_vector, &mask);
        writew(mask, ndev->reg_ofs.ldb_mask);
 
+       tasklet_disable(&ndev->db_cb[idx].irq_work);
+
        ndev->db_cb[idx].callback = NULL;
 }
 
@@ -678,6 +702,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                                return -EINVAL;
 
                        ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
+                       ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                        ndev->reg_ofs.spad_write = ndev->mw[1].vbase +
                                                   SNB_SPAD_OFFSET;
                        ndev->reg_ofs.rdb = ndev->mw[1].vbase +
@@ -688,8 +713,21 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                         */
                        writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base +
                               SNB_PBAR4LMT_OFFSET);
+                       /* HW errata on the Limit registers.  They can only be
+                        * written when the base register is 4GB aligned and
+                        * < 32bit.  This should already be the case based on the
+                        * driver defaults, but write the Limit registers first
+                        * just in case.
+                        */
                } else {
                        ndev->limits.max_mw = SNB_MAX_MW;
+
+                       /* HW Errata on bit 14 of b2bdoorbell register.  Writes
+                        * will not be mirrored to the remote system.  Shrink
+                        * the number of bits by one, since bit 14 is the last
+                        * bit.
+                        */
+                       ndev->limits.max_db_bits = SNB_MAX_DB_BITS - 1;
                        ndev->reg_ofs.spad_write = ndev->reg_base +
                                                   SNB_B2B_SPAD_OFFSET;
                        ndev->reg_ofs.rdb = ndev->reg_base +
@@ -699,6 +737,12 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                         * something silly
                         */
                        writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET);
+                       /* HW errata on the Limit registers.  They can only be
+                        * written when the base register is 4GB aligned and
+                        * < 32bit.  This should already be the case based on the
+                        * driver defaults, but write the Limit registers first
+                        * just in case.
+                        */
                }
 
                /* The Xeon errata workaround requires setting SBAR Base
@@ -769,6 +813,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                 * have an equal amount.
                 */
                ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+               ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                /* Note: The SDOORBELL is the cause of the errata.  You REALLY
                 * don't want to touch it.
                 */
@@ -793,6 +838,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                 * have an equal amount.
                 */
                ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+               ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
                ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
                ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET;
@@ -819,7 +865,6 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
        ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET;
        ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET;
 
-       ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
        ndev->limits.msix_cnt = SNB_MSIX_CNT;
        ndev->bits_per_vector = SNB_DB_BITS_PER_VEC;
 
@@ -934,12 +979,16 @@ static irqreturn_t bwd_callback_msix_irq(int irq, void *data)
 {
        struct ntb_db_cb *db_cb = data;
        struct ntb_device *ndev = db_cb->ndev;
+       unsigned long mask;
 
        dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
                db_cb->db_num);
 
-       if (db_cb->callback)
-               db_cb->callback(db_cb->data, db_cb->db_num);
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       tasklet_schedule(&db_cb->irq_work);
 
        /* No need to check for the specific HB irq, any interrupt means
         * we're connected.
@@ -955,12 +1004,16 @@ static irqreturn_t xeon_callback_msix_irq(int irq, void *data)
 {
        struct ntb_db_cb *db_cb = data;
        struct ntb_device *ndev = db_cb->ndev;
+       unsigned long mask;
 
        dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
                db_cb->db_num);
 
-       if (db_cb->callback)
-               db_cb->callback(db_cb->data, db_cb->db_num);
+       mask = readw(ndev->reg_ofs.ldb_mask);
+       set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+       writew(mask, ndev->reg_ofs.ldb_mask);
+
+       tasklet_schedule(&db_cb->irq_work);
 
        /* On Sandybridge, there are 16 bits in the interrupt register
         * but only 4 vectors.  So, 5 bits are assigned to the first 3
@@ -986,7 +1039,7 @@ static irqreturn_t xeon_event_msix_irq(int irq, void *dev)
                dev_err(&ndev->pdev->dev, "Error determining link status\n");
 
        /* bit 15 is always the link bit */
-       writew(1 << ndev->limits.max_db_bits, ndev->reg_ofs.ldb);
+       writew(1 << SNB_LINK_DB, ndev->reg_ofs.ldb);
 
        return IRQ_HANDLED;
 }
@@ -1075,6 +1128,10 @@ static int ntb_setup_msix(struct ntb_device *ndev)
                         "Only %d MSI-X vectors.  Limiting the number of queues to that number.\n",
                         rc);
                msix_entries = rc;
+
+               rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);
+               if (rc)
+                       goto err1;
        }
 
        for (i = 0; i < msix_entries; i++) {
@@ -1176,9 +1233,10 @@ static int ntb_setup_interrupts(struct ntb_device *ndev)
         */
        if (ndev->hw_type == BWD_HW)
                writeq(~0, ndev->reg_ofs.ldb_mask);
-       else
-               writew(~(1 << ndev->limits.max_db_bits),
-                      ndev->reg_ofs.ldb_mask);
+       else {
+               u16 var = 1 << SNB_LINK_DB;
+               writew(~var, ndev->reg_ofs.ldb_mask);
+       }
 
        rc = ntb_setup_msix(ndev);
        if (!rc)
@@ -1286,6 +1344,39 @@ static void ntb_free_debugfs(struct ntb_device *ndev)
        }
 }
 
+static void ntb_hw_link_up(struct ntb_device *ndev)
+{
+       if (ndev->conn_type == NTB_CONN_TRANSPARENT)
+               ntb_link_event(ndev, NTB_LINK_UP);
+       else {
+               u32 ntb_cntl;
+
+               /* Let's bring the NTB link up */
+               ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+               ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
+               ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
+               ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP;
+               writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+       }
+}
+
+static void ntb_hw_link_down(struct ntb_device *ndev)
+{
+       u32 ntb_cntl;
+
+       if (ndev->conn_type == NTB_CONN_TRANSPARENT) {
+               ntb_link_event(ndev, NTB_LINK_DOWN);
+               return;
+       }
+
+       /* Bring NTB link down */
+       ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP);
+       ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;
+       writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+}
+
 static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
        struct ntb_device *ndev;
@@ -1374,9 +1465,7 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
        if (rc)
                goto err6;
 
-       /* Let's bring the NTB link up */
-       writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,
-              ndev->reg_ofs.lnk_cntl);
+       ntb_hw_link_up(ndev);
 
        return 0;
 
@@ -1406,12 +1495,8 @@ static void ntb_pci_remove(struct pci_dev *pdev)
 {
        struct ntb_device *ndev = pci_get_drvdata(pdev);
        int i;
-       u32 ntb_cntl;
 
-       /* Bring NTB link down */
-       ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
-       ntb_cntl |= NTB_CNTL_LINK_DISABLE;
-       writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+       ntb_hw_link_down(ndev);
 
        ntb_transport_free(ndev->ntb_transport);
 
index 0a31cedae7d42f9227d125bfabe97297b47255d9..bbdb7edca10cd8647e4b739dfab29f1ed33fc1e6 100644 (file)
@@ -106,10 +106,11 @@ struct ntb_mw {
 };
 
 struct ntb_db_cb {
-       void (*callback) (void *data, int db_num);
+       int (*callback)(void *data, int db_num);
        unsigned int db_num;
        void *data;
        struct ntb_device *ndev;
+       struct tasklet_struct irq_work;
 };
 
 struct ntb_device {
@@ -228,8 +229,8 @@ struct ntb_device *ntb_register_transport(struct pci_dev *pdev,
 void ntb_unregister_transport(struct ntb_device *ndev);
 void ntb_set_mw_addr(struct ntb_device *ndev, unsigned int mw, u64 addr);
 int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
-                            void *data, void (*db_cb_func) (void *data,
-                                                            int db_num));
+                            void *data, int (*db_cb_func)(void *data,
+                                                          int db_num));
 void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx);
 int ntb_register_event_callback(struct ntb_device *ndev,
                                void (*event_cb_func) (void *handle,
index aa4bdd393c58ee2c4cf40105b1644afdcb19913c..9774506419d75ba1a5dc08a5f0e4d52e90d33ad7 100644 (file)
@@ -55,6 +55,7 @@
 #define SNB_MAX_COMPAT_SPADS   16
 /* Reserve the uppermost bit for link interrupt */
 #define SNB_MAX_DB_BITS                15
+#define SNB_LINK_DB            15
 #define SNB_DB_BITS_PER_VEC    5
 #define SNB_MAX_MW             2
 #define SNB_ERRATA_MAX_MW      1
@@ -75,9 +76,6 @@
 #define SNB_SBAR2XLAT_OFFSET   0x0030
 #define SNB_SBAR4XLAT_OFFSET   0x0038
 #define SNB_SBAR0BASE_OFFSET   0x0040
-#define SNB_SBAR0BASE_OFFSET   0x0040
-#define SNB_SBAR2BASE_OFFSET   0x0048
-#define SNB_SBAR4BASE_OFFSET   0x0050
 #define SNB_SBAR2BASE_OFFSET   0x0048
 #define SNB_SBAR4BASE_OFFSET   0x0050
 #define SNB_NTBCNTL_OFFSET     0x0058
 #define BWD_LTSSMSTATEJMP_FORCEDETECT  (1 << 2)
 #define BWD_IBIST_ERR_OFLOW    0x7FFF7FFF
 
-#define NTB_CNTL_CFG_LOCK      (1 << 0)
-#define NTB_CNTL_LINK_DISABLE  (1 << 1)
-#define NTB_CNTL_BAR23_SNOOP   (1 << 2)
-#define NTB_CNTL_BAR45_SNOOP   (1 << 6)
-#define BWD_CNTL_LINK_DOWN     (1 << 16)
+#define NTB_CNTL_CFG_LOCK              (1 << 0)
+#define NTB_CNTL_LINK_DISABLE          (1 << 1)
+#define NTB_CNTL_S2P_BAR23_SNOOP       (1 << 2)
+#define NTB_CNTL_P2S_BAR23_SNOOP       (1 << 4)
+#define NTB_CNTL_S2P_BAR45_SNOOP       (1 << 6)
+#define NTB_CNTL_P2S_BAR45_SNOOP       (1 << 8)
+#define BWD_CNTL_LINK_DOWN             (1 << 16)
 
 #define NTB_PPD_OFFSET         0x00D4
 #define SNB_PPD_CONN_TYPE      0x0003
index d0222f13d154808f3cfa4ed3cab26cd1a7b899ee..3217f394d45b106051b282f824be1413b5efa65d 100644 (file)
@@ -119,7 +119,6 @@ struct ntb_transport_qp {
 
        void (*rx_handler) (struct ntb_transport_qp *qp, void *qp_data,
                            void *data, int len);
-       struct tasklet_struct rx_work;
        struct list_head rx_pend_q;
        struct list_head rx_free_q;
        spinlock_t ntb_rx_pend_q_lock;
@@ -584,11 +583,8 @@ static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
        return 0;
 }
 
-static void ntb_qp_link_cleanup(struct work_struct *work)
+static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp)
 {
-       struct ntb_transport_qp *qp = container_of(work,
-                                                  struct ntb_transport_qp,
-                                                  link_cleanup);
        struct ntb_transport *nt = qp->transport;
        struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
 
@@ -602,6 +598,16 @@ static void ntb_qp_link_cleanup(struct work_struct *work)
 
        dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
        qp->qp_link = NTB_LINK_DOWN;
+}
+
+static void ntb_qp_link_cleanup_work(struct work_struct *work)
+{
+       struct ntb_transport_qp *qp = container_of(work,
+                                                  struct ntb_transport_qp,
+                                                  link_cleanup);
+       struct ntb_transport *nt = qp->transport;
+
+       ntb_qp_link_cleanup(qp);
 
        if (nt->transport_link == NTB_LINK_UP)
                schedule_delayed_work(&qp->link_work,
@@ -613,22 +619,20 @@ static void ntb_qp_link_down(struct ntb_transport_qp *qp)
        schedule_work(&qp->link_cleanup);
 }
 
-static void ntb_transport_link_cleanup(struct work_struct *work)
+static void ntb_transport_link_cleanup(struct ntb_transport *nt)
 {
-       struct ntb_transport *nt = container_of(work, struct ntb_transport,
-                                               link_cleanup);
        int i;
 
+       /* Pass along the info to any clients */
+       for (i = 0; i < nt->max_qps; i++)
+               if (!test_bit(i, &nt->qp_bitmap))
+                       ntb_qp_link_cleanup(&nt->qps[i]);
+
        if (nt->transport_link == NTB_LINK_DOWN)
                cancel_delayed_work_sync(&nt->link_work);
        else
                nt->transport_link = NTB_LINK_DOWN;
 
-       /* Pass along the info to any clients */
-       for (i = 0; i < nt->max_qps; i++)
-               if (!test_bit(i, &nt->qp_bitmap))
-                       ntb_qp_link_down(&nt->qps[i]);
-
        /* The scratchpad registers keep the values if the remote side
         * goes down, blast them now to give them a sane value the next
         * time they are accessed
@@ -637,6 +641,14 @@ static void ntb_transport_link_cleanup(struct work_struct *work)
                ntb_write_local_spad(nt->ndev, i, 0);
 }
 
+static void ntb_transport_link_cleanup_work(struct work_struct *work)
+{
+       struct ntb_transport *nt = container_of(work, struct ntb_transport,
+                                               link_cleanup);
+
+       ntb_transport_link_cleanup(nt);
+}
+
 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event)
 {
        struct ntb_transport *nt = data;
@@ -880,7 +892,7 @@ static int ntb_transport_init_queue(struct ntb_transport *nt,
        }
 
        INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work);
-       INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup);
+       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);
@@ -936,7 +948,7 @@ int ntb_transport_init(struct pci_dev *pdev)
        }
 
        INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
-       INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup);
+       INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup_work);
 
        rc = ntb_register_event_callback(nt->ndev,
                                         ntb_transport_event_callback);
@@ -972,7 +984,7 @@ void ntb_transport_free(void *transport)
        struct ntb_device *ndev = nt->ndev;
        int i;
 
-       nt->transport_link = NTB_LINK_DOWN;
+       ntb_transport_link_cleanup(nt);
 
        /* verify that all the qp's are freed */
        for (i = 0; i < nt->max_qps; i++) {
@@ -1188,11 +1200,14 @@ err:
        goto out;
 }
 
-static void ntb_transport_rx(unsigned long data)
+static int ntb_transport_rxc_db(void *data, int db_num)
 {
-       struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data;
+       struct ntb_transport_qp *qp = data;
        int rc, i;
 
+       dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n",
+               __func__, db_num);
+
        /* Limit the number of packets processed in a single interrupt to
         * provide fairness to others
         */
@@ -1204,16 +1219,8 @@ static void ntb_transport_rx(unsigned long data)
 
        if (qp->dma_chan)
                dma_async_issue_pending(qp->dma_chan);
-}
-
-static void ntb_transport_rxc_db(void *data, int db_num)
-{
-       struct ntb_transport_qp *qp = data;
-
-       dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n",
-               __func__, db_num);
 
-       tasklet_schedule(&qp->rx_work);
+       return i;
 }
 
 static void ntb_tx_copy_callback(void *data)
@@ -1432,11 +1439,12 @@ ntb_transport_create_queue(void *data, struct pci_dev *pdev,
        qp->tx_handler = handlers->tx_handler;
        qp->event_handler = handlers->event_handler;
 
+       dmaengine_get();
        qp->dma_chan = dma_find_channel(DMA_MEMCPY);
-       if (!qp->dma_chan)
+       if (!qp->dma_chan) {
+               dmaengine_put();
                dev_info(&pdev->dev, "Unable to allocate DMA channel, using CPU instead\n");
-       else
-               dmaengine_get();
+       }
 
        for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
                entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
@@ -1458,25 +1466,23 @@ ntb_transport_create_queue(void *data, struct pci_dev *pdev,
                             &qp->tx_free_q);
        }
 
-       tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp);
-
        rc = ntb_register_db_callback(qp->ndev, free_queue, qp,
                                      ntb_transport_rxc_db);
        if (rc)
-               goto err3;
+               goto err2;
 
        dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num);
 
        return qp;
 
-err3:
-       tasklet_disable(&qp->rx_work);
 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)))
                kfree(entry);
+       if (qp->dma_chan)
+               dmaengine_put();
        set_bit(free_queue, &nt->qp_bitmap);
 err:
        return NULL;
@@ -1515,7 +1521,6 @@ void ntb_transport_free_queue(struct ntb_transport_qp *qp)
        }
 
        ntb_unregister_db_callback(qp->ndev, qp->qp_num);
-       tasklet_disable(&qp->rx_work);
 
        cancel_delayed_work_sync(&qp->link_work);