[PATCH 3.13.y-ckt 88/95] mlx5_core: Fix PowerPC support

[Kamal Mostafa]

3.13.11-ckt21 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eli Cohen <eli at dev.mellanox.co.il>

commit 05bdb2ab6b09f2306f0afe0f60f4b9abffa7aba4 upstream.

1. Fix derivation of sub-page index from the dma address in free_4k.
2. Fix the DMA address passed to dma_unmap_page by masking it properly.

Signed-off-by: Eli Cohen <eli at mellanox.com>
Signed-off-by: Roland Dreier <roland at purestorage.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c | 9 +++++----
 include/linux/mlx5/device.h                         | 3 ++-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c
index 37b6ad1..9959199 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/pagealloc.c
@@ -99,7 +99,7 @@ enum {
 
 enum {
 	MLX5_MAX_RECLAIM_TIME_MILI	= 5000,
-	MLX5_NUM_4K_IN_PAGE		= PAGE_SIZE / 4096,
+	MLX5_NUM_4K_IN_PAGE		= PAGE_SIZE / MLX5_ADAPTER_PAGE_SIZE,
 };
 
 static int insert_page(struct mlx5_core_dev *dev, u64 addr, struct page *page, u16 func_id)
@@ -208,7 +208,7 @@ static int alloc_4k(struct mlx5_core_dev *dev, u64 *addr)
 	if (!fp->free_count)
 		list_del(&fp->list);
 
-	*addr = fp->addr + n * 4096;
+	*addr = fp->addr + n * MLX5_ADAPTER_PAGE_SIZE;
 
 	return 0;
 }
@@ -224,14 +224,15 @@ static void free_4k(struct mlx5_core_dev *dev, u64 addr)
 		return;
 	}
 
-	n = (addr & ~PAGE_MASK) % 4096;
+	n = (addr & ~PAGE_MASK) >> MLX5_ADAPTER_PAGE_SHIFT;
 	fwp->free_count++;
 	set_bit(n, &fwp->bitmask);
 	if (fwp->free_count == MLX5_NUM_4K_IN_PAGE) {
 		rb_erase(&fwp->rb_node, &dev->priv.page_root);
 		if (fwp->free_count != 1)
 			list_del(&fwp->list);
-		dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE, DMA_BIDIRECTIONAL);
+		dma_unmap_page(&dev->pdev->dev, addr & PAGE_MASK, PAGE_SIZE,
+			       DMA_BIDIRECTIONAL);
 		__free_page(fwp->page);
 		kfree(fwp);
 	} else if (fwp->free_count == 1) {
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index da78875..90a3b45 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -231,7 +231,8 @@ enum {
 };
 
 enum {
-	MLX5_ADAPTER_PAGE_SHIFT		= 12
+	MLX5_ADAPTER_PAGE_SHIFT		= 12,
+	MLX5_ADAPTER_PAGE_SIZE		= 1 << MLX5_ADAPTER_PAGE_SHIFT,
 };
 
 enum {
-- 
1.9.1