1 files changed, 7 insertions, 18 deletions

diff --git a/drivers/dma/ioatdma.c b/drivers/dma/ioatdma.c
index 5fbe56b5cea0..41b18c5a3141 100644
--- a/drivers/dma/ioatdma.c
+++ b/drivers/dma/ioatdma.c
@@ -191,17 +191,12 @@ static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
         int i;
         LIST_HEAD(tmp_list);
 
-        /*
-         * In-use bit automatically set by reading chanctrl
-         * If 0, we got it, if 1, someone else did
-         */
-        chanctrl = readw(ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
-        if (chanctrl & IOAT_CHANCTRL_CHANNEL_IN_USE)
-                return -EBUSY;
+        /* have we already been set up? */
+        if (!list_empty(&ioat_chan->free_desc))
+                return INITIAL_IOAT_DESC_COUNT;
 
         /* Setup register to interrupt and write completion status on error */
-        chanctrl = IOAT_CHANCTRL_CHANNEL_IN_USE |
-                IOAT_CHANCTRL_ERR_INT_EN |
+        chanctrl = IOAT_CHANCTRL_ERR_INT_EN |
                 IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
                 IOAT_CHANCTRL_ERR_COMPLETION_EN;
         writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
@@ -282,11 +277,6 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
                         in_use_descs - 1);
 
         ioat_chan->last_completion = ioat_chan->completion_addr = 0;
-
-        /* Tell hw the chan is free */
-        chanctrl = readw(ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
-        chanctrl &= ~IOAT_CHANCTRL_CHANNEL_IN_USE;
-        writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
 }
 
 static struct dma_async_tx_descriptor *
@@ -347,8 +337,7 @@ ioat_dma_prep_memcpy(struct dma_chan *chan, size_t len, int int_en)
         new->async_tx.ack = 0; /* client is in control of this ack */
         new->async_tx.cookie = -EBUSY;
 
-        pci_unmap_len_set(new, src_len, orig_len);
-        pci_unmap_len_set(new, dst_len, orig_len);
+        pci_unmap_len_set(new, len, orig_len);
         spin_unlock_bh(&ioat_chan->desc_lock);
 
         return new ? &new->async_tx : NULL;
@@ -423,11 +412,11 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *chan)
                         */
                         pci_unmap_page(chan->device->pdev,
                                         pci_unmap_addr(desc, dst),
-                                        pci_unmap_len(desc, dst_len),
+                                        pci_unmap_len(desc, len),
                                         PCI_DMA_FROMDEVICE);
                         pci_unmap_page(chan->device->pdev,
                                         pci_unmap_addr(desc, src),
-                                        pci_unmap_len(desc, src_len),
+                                        pci_unmap_len(desc, len),
                                         PCI_DMA_TODEVICE);
                 }