3 files changed, 30 insertions, 15 deletions

diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index bf57b3cb16ab..0bc00991d310 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -779,6 +779,7 @@ efx_realloc_channels(struct efx_nic *efx, u32 rxq_entries, u32 txq_entries)
                                                 tx_queue->txd.entries);
         }
 
+        efx_device_detach_sync(efx);
         efx_stop_all(efx);
         efx_stop_interrupts(efx, true);
 
@@ -832,6 +833,7 @@ out:
 
         efx_start_interrupts(efx, true);
         efx_start_all(efx);
+        netif_device_attach(efx->net_dev);
         return rc;
 
 rollback:
@@ -1641,8 +1643,12 @@ static void efx_stop_all(struct efx_nic *efx)
         /* Flush efx_mac_work(), refill_workqueue, monitor_work */
         efx_flush_all(efx);
 
-        /* Stop the kernel transmit interface late, so the watchdog
-         * timer isn't ticking over the flush */
+        /* Stop the kernel transmit interface.  This is only valid if
+         * the device is stopped or detached; otherwise the watchdog
+         * may fire immediately.
+         */
+        WARN_ON(netif_running(efx->net_dev) &&
+                netif_device_present(efx->net_dev));
         netif_tx_disable(efx->net_dev);
 
         efx_stop_datapath(efx);
@@ -1963,16 +1969,18 @@ static int efx_change_mtu(struct net_device *net_dev, int new_mtu)
         if (new_mtu > EFX_MAX_MTU)
                 return -EINVAL;
 
-        efx_stop_all(efx);
-
         netif_dbg(efx, drv, efx->net_dev, "changing MTU to %d\n", new_mtu);
 
+        efx_device_detach_sync(efx);
+        efx_stop_all(efx);
+
         mutex_lock(&efx->mac_lock);
         net_dev->mtu = new_mtu;
         efx->type->reconfigure_mac(efx);
         mutex_unlock(&efx->mac_lock);
 
         efx_start_all(efx);
+        netif_device_attach(efx->net_dev);
         return 0;
 }
 
diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h
index 2d756c1d7142..0a90abd2421b 100644
--- a/drivers/net/ethernet/sfc/net_driver.h
+++ b/drivers/net/ethernet/sfc/net_driver.h
@@ -210,6 +210,7 @@ struct efx_tx_queue {
  *      Will be %NULL if the buffer slot is currently free.
  * @page: The associated page buffer. Valif iff @flags & %EFX_RX_BUF_PAGE.
  *      Will be %NULL if the buffer slot is currently free.
+ * @page_offset: Offset within page. Valid iff @flags & %EFX_RX_BUF_PAGE.
  * @len: Buffer length, in bytes.
  * @flags: Flags for buffer and packet state.
  */
@@ -219,7 +220,8 @@ struct efx_rx_buffer {
                 struct sk_buff *skb;
                 struct page *page;
         } u;
-        unsigned int len;
+        u16 page_offset;
+        u16 len;
         u16 flags;
 };
 #define EFX_RX_BUF_PAGE         0x0001
diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c
index d780a0d096b4..879ff5849bbd 100644
--- a/drivers/net/ethernet/sfc/rx.c
+++ b/drivers/net/ethernet/sfc/rx.c
@@ -90,11 +90,7 @@ static unsigned int rx_refill_threshold;
 static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx,
                                              struct efx_rx_buffer *buf)
 {
-        /* Offset is always within one page, so we don't need to consider
-         * the page order.
-         */
-        return ((unsigned int) buf->dma_addr & (PAGE_SIZE - 1)) +
-                efx->type->rx_buffer_hash_size;
+        return buf->page_offset + efx->type->rx_buffer_hash_size;
 }
 static inline unsigned int efx_rx_buf_size(struct efx_nic *efx)
 {
@@ -187,6 +183,7 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
         struct efx_nic *efx = rx_queue->efx;
         struct efx_rx_buffer *rx_buf;
         struct page *page;
+        unsigned int page_offset;
         struct efx_rx_page_state *state;
         dma_addr_t dma_addr;
         unsigned index, count;
@@ -211,12 +208,14 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
                 state->dma_addr = dma_addr;
 
                 dma_addr += sizeof(struct efx_rx_page_state);
+                page_offset = sizeof(struct efx_rx_page_state);
 
         split:
                 index = rx_queue->added_count & rx_queue->ptr_mask;
                 rx_buf = efx_rx_buffer(rx_queue, index);
                 rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
                 rx_buf->u.page = page;
+                rx_buf->page_offset = page_offset;
                 rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
                 rx_buf->flags = EFX_RX_BUF_PAGE;
                 ++rx_queue->added_count;
@@ -227,6 +226,7 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
                         /* Use the second half of the page */
                         get_page(page);
                         dma_addr += (PAGE_SIZE >> 1);
+                        page_offset += (PAGE_SIZE >> 1);
                         ++count;
                         goto split;
                 }
@@ -236,7 +236,8 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
 }
 
 static void efx_unmap_rx_buffer(struct efx_nic *efx,
-                                struct efx_rx_buffer *rx_buf)
+                                struct efx_rx_buffer *rx_buf,
+                                unsigned int used_len)
 {
         if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
                 struct efx_rx_page_state *state;
@@ -247,6 +248,10 @@ static void efx_unmap_rx_buffer(struct efx_nic *efx,
                                        state->dma_addr,
                                        efx_rx_buf_size(efx),
                                        DMA_FROM_DEVICE);
+                } else if (used_len) {
+                        dma_sync_single_for_cpu(&efx->pci_dev->dev,
+                                                rx_buf->dma_addr, used_len,
+                                                DMA_FROM_DEVICE);
                 }
         } else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
                 dma_unmap_single(&efx->pci_dev->dev, rx_buf->dma_addr,
@@ -269,7 +274,7 @@ static void efx_free_rx_buffer(struct efx_nic *efx,
 static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
                                struct efx_rx_buffer *rx_buf)
 {
-        efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
+        efx_unmap_rx_buffer(rx_queue->efx, rx_buf, 0);
         efx_free_rx_buffer(rx_queue->efx, rx_buf);
 }
 
@@ -535,10 +540,10 @@ void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
                 goto out;
         }
 
-        /* Release card resources - assumes all RX buffers consumed in-order
-         * per RX queue
+        /* Release and/or sync DMA mapping - assumes all RX buffers
+         * consumed in-order per RX queue
          */
-        efx_unmap_rx_buffer(efx, rx_buf);
+        efx_unmap_rx_buffer(efx, rx_buf, len);
 
         /* Prefetch nice and early so data will (hopefully) be in cache by
          * the time we look at it.