From 64599cca51de08cef94bc13a0f98351e5bb01f41 Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Thu, 2 Apr 2015 17:07:25 +0300 Subject: [PATCH] net/mlx5_core: Use coherent memory for command interface page Use coherent memory for the commands descriptor page. Take measures to make sure the page is aligned to MLX5_ADAPTER_PAGE_SIZE as required by the hardware. Reported-by: Yevgeny Kliteynik Signed-off-by: Eli Cohen Signed-off-by: Saeed Mahameed Signed-off-by: David S. Miller --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 72 +++++++++++++------ include/linux/mlx5/driver.h | 3 + 2 files changed, 52 insertions(+), 23 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c index a2853057c779..43a73d36b01d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -1319,6 +1319,45 @@ static int create_msg_cache(struct mlx5_core_dev *dev) return err; } +static int alloc_cmd_page(struct mlx5_core_dev *dev, struct mlx5_cmd *cmd) +{ + struct device *ddev = &dev->pdev->dev; + + cmd->cmd_alloc_buf = dma_zalloc_coherent(ddev, MLX5_ADAPTER_PAGE_SIZE, + &cmd->alloc_dma, GFP_KERNEL); + if (!cmd->cmd_alloc_buf) + return -ENOMEM; + + /* make sure it is aligned to 4K */ + if (!((uintptr_t)cmd->cmd_alloc_buf & (MLX5_ADAPTER_PAGE_SIZE - 1))) { + cmd->cmd_buf = cmd->cmd_alloc_buf; + cmd->dma = cmd->alloc_dma; + cmd->alloc_size = MLX5_ADAPTER_PAGE_SIZE; + return 0; + } + + dma_free_coherent(ddev, MLX5_ADAPTER_PAGE_SIZE, cmd->cmd_alloc_buf, + cmd->alloc_dma); + cmd->cmd_alloc_buf = dma_zalloc_coherent(ddev, + 2 * MLX5_ADAPTER_PAGE_SIZE - 1, + &cmd->alloc_dma, GFP_KERNEL); + if (!cmd->cmd_alloc_buf) + return -ENOMEM; + + cmd->cmd_buf = PTR_ALIGN(cmd->cmd_alloc_buf, MLX5_ADAPTER_PAGE_SIZE); + cmd->dma = ALIGN(cmd->alloc_dma, MLX5_ADAPTER_PAGE_SIZE); + cmd->alloc_size = 2 * MLX5_ADAPTER_PAGE_SIZE - 1; + return 0; +} + +static void free_cmd_page(struct mlx5_core_dev *dev, struct mlx5_cmd *cmd) +{ + struct device *ddev = &dev->pdev->dev; + + dma_free_coherent(ddev, cmd->alloc_size, cmd->cmd_alloc_buf, + cmd->alloc_dma); +} + int mlx5_cmd_init(struct mlx5_core_dev *dev) { int size = sizeof(struct mlx5_cmd_prot_block); @@ -1341,17 +1380,9 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) if (!cmd->pool) return -ENOMEM; - cmd->cmd_buf = (void *)__get_free_pages(GFP_ATOMIC, 0); - if (!cmd->cmd_buf) { - err = -ENOMEM; + err = alloc_cmd_page(dev, cmd); + if (err) goto err_free_pool; - } - cmd->dma = dma_map_single(&dev->pdev->dev, cmd->cmd_buf, PAGE_SIZE, - DMA_BIDIRECTIONAL); - if (dma_mapping_error(&dev->pdev->dev, cmd->dma)) { - err = -ENOMEM; - goto err_free; - } cmd_l = ioread32be(&dev->iseg->cmdq_addr_l_sz) & 0xff; cmd->log_sz = cmd_l >> 4 & 0xf; @@ -1360,13 +1391,13 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) dev_err(&dev->pdev->dev, "firmware reports too many outstanding commands %d\n", 1 << cmd->log_sz); err = -EINVAL; - goto err_map; + goto err_free_page; } if (cmd->log_sz + cmd->log_stride > MLX5_ADAPTER_PAGE_SHIFT) { dev_err(&dev->pdev->dev, "command queue size overflow\n"); err = -EINVAL; - goto err_map; + goto err_free_page; } cmd->checksum_disabled = 1; @@ -1378,7 +1409,7 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) dev_err(&dev->pdev->dev, "driver does not support command interface version. driver %d, firmware %d\n", CMD_IF_REV, cmd->cmdif_rev); err = -ENOTSUPP; - goto err_map; + goto err_free_page; } spin_lock_init(&cmd->alloc_lock); @@ -1394,7 +1425,7 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) if (cmd_l & 0xfff) { dev_err(&dev->pdev->dev, "invalid command queue address\n"); err = -ENOMEM; - goto err_map; + goto err_free_page; } iowrite32be(cmd_h, &dev->iseg->cmdq_addr_h); @@ -1410,7 +1441,7 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) err = create_msg_cache(dev); if (err) { dev_err(&dev->pdev->dev, "failed to create command cache\n"); - goto err_map; + goto err_free_page; } set_wqname(dev); @@ -1435,11 +1466,8 @@ int mlx5_cmd_init(struct mlx5_core_dev *dev) err_cache: destroy_msg_cache(dev); -err_map: - dma_unmap_single(&dev->pdev->dev, cmd->dma, PAGE_SIZE, - DMA_BIDIRECTIONAL); -err_free: - free_pages((unsigned long)cmd->cmd_buf, 0); +err_free_page: + free_cmd_page(dev, cmd); err_free_pool: pci_pool_destroy(cmd->pool); @@ -1455,9 +1483,7 @@ void mlx5_cmd_cleanup(struct mlx5_core_dev *dev) clean_debug_files(dev); destroy_workqueue(cmd->wq); destroy_msg_cache(dev); - dma_unmap_single(&dev->pdev->dev, cmd->dma, PAGE_SIZE, - DMA_BIDIRECTIONAL); - free_pages((unsigned long)cmd->cmd_buf, 0); + free_cmd_page(dev, cmd); pci_pool_destroy(cmd->pool); } EXPORT_SYMBOL(mlx5_cmd_cleanup); diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h index 166d9315fe4b..8d8ca6d9b03b 100644 --- a/include/linux/mlx5/driver.h +++ b/include/linux/mlx5/driver.h @@ -232,6 +232,9 @@ struct mlx5_cmd_stats { }; struct mlx5_cmd { + void *cmd_alloc_buf; + dma_addr_t alloc_dma; + int alloc_size; void *cmd_buf; dma_addr_t dma; u16 cmdif_rev;