1 files changed, 37 insertions, 5 deletions

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index 80505aeecf9e..170e8e60cdb7 100644
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -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;
 }
 
@@ -955,12 +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.
@@ -976,12 +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