From c1b43dca137f2154845122417fba86d4bae67182 Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Tue, 22 Mar 2011 22:38:41 +0000 Subject: mlx4: Add blue flame support for kernel consumers Using blue flame can improve latency by allowing the HW to more efficiently access the WQE. This patch presents two functions that are used to allocate or release HW resources for using blue flame; the caller need to supply a struct mlx4_bf object when allocating resources. Consumers that make use of this API should post doorbells to the UAR object pointed by the initialized struct mlx4_bf; Signed-off-by: Eli Cohen Signed-off-by: David S. Miller --- drivers/net/mlx4/pd.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) (limited to 'drivers/net/mlx4/pd.c') diff --git a/drivers/net/mlx4/pd.c b/drivers/net/mlx4/pd.c index c4988d6bd5b2..5210a0f31413 100644 --- a/drivers/net/mlx4/pd.c +++ b/drivers/net/mlx4/pd.c @@ -32,6 +32,7 @@ */ #include +#include #include @@ -77,6 +78,7 @@ int mlx4_uar_alloc(struct mlx4_dev *dev, struct mlx4_uar *uar) return -ENOMEM; uar->pfn = (pci_resource_start(dev->pdev, 2) >> PAGE_SHIFT) + uar->index; + uar->map = NULL; return 0; } @@ -88,6 +90,98 @@ void mlx4_uar_free(struct mlx4_dev *dev, struct mlx4_uar *uar) } EXPORT_SYMBOL_GPL(mlx4_uar_free); +int mlx4_bf_alloc(struct mlx4_dev *dev, struct mlx4_bf *bf) +{ + struct mlx4_priv *priv = mlx4_priv(dev); + struct mlx4_uar *uar; + int err = 0; + int idx; + + if (!priv->bf_mapping) + return -ENOMEM; + + mutex_lock(&priv->bf_mutex); + if (!list_empty(&priv->bf_list)) + uar = list_entry(priv->bf_list.next, struct mlx4_uar, bf_list); + else { + uar = kmalloc(sizeof *uar, GFP_KERNEL); + if (!uar) { + err = -ENOMEM; + goto out; + } + err = mlx4_uar_alloc(dev, uar); + if (err) + goto free_kmalloc; + + uar->map = ioremap(uar->pfn << PAGE_SHIFT, PAGE_SIZE); + if (!uar->map) { + err = -ENOMEM; + goto free_uar; + } + + uar->bf_map = io_mapping_map_wc(priv->bf_mapping, uar->index << PAGE_SHIFT); + if (!uar->bf_map) { + err = -ENOMEM; + goto unamp_uar; + } + uar->free_bf_bmap = 0; + list_add(&uar->bf_list, &priv->bf_list); + } + + bf->uar = uar; + idx = ffz(uar->free_bf_bmap); + uar->free_bf_bmap |= 1 << idx; + bf->uar = uar; + bf->offset = 0; + bf->buf_size = dev->caps.bf_reg_size / 2; + bf->reg = uar->bf_map + idx * dev->caps.bf_reg_size; + if (uar->free_bf_bmap == (1 << dev->caps.bf_regs_per_page) - 1) + list_del_init(&uar->bf_list); + + goto out; + +unamp_uar: + bf->uar = NULL; + iounmap(uar->map); + +free_uar: + mlx4_uar_free(dev, uar); + +free_kmalloc: + kfree(uar); + +out: + mutex_unlock(&priv->bf_mutex); + return err; +} +EXPORT_SYMBOL_GPL(mlx4_bf_alloc); + +void mlx4_bf_free(struct mlx4_dev *dev, struct mlx4_bf *bf) +{ + struct mlx4_priv *priv = mlx4_priv(dev); + int idx; + + if (!bf->uar || !bf->uar->bf_map) + return; + + mutex_lock(&priv->bf_mutex); + idx = (bf->reg - bf->uar->bf_map) / dev->caps.bf_reg_size; + bf->uar->free_bf_bmap &= ~(1 << idx); + if (!bf->uar->free_bf_bmap) { + if (!list_empty(&bf->uar->bf_list)) + list_del(&bf->uar->bf_list); + + io_mapping_unmap(bf->uar->bf_map); + iounmap(bf->uar->map); + mlx4_uar_free(dev, bf->uar); + kfree(bf->uar); + } else if (list_empty(&bf->uar->bf_list)) + list_add(&bf->uar->bf_list, &priv->bf_list); + + mutex_unlock(&priv->bf_mutex); +} +EXPORT_SYMBOL_GPL(mlx4_bf_free); + int mlx4_init_uar_table(struct mlx4_dev *dev) { if (dev->caps.num_uars <= 128) { -- cgit v1.2.3 From 9ace5e0176f165f04537497143506621d33a0139 Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Tue, 22 Mar 2011 22:38:48 +0000 Subject: mlx4_core: reserve UARs for userspace consumers Do not allow a kernel consumer to allocate a UAR to serve for blue flame if the number of available UARs gets below MLX4_NUM_RESERVED_UARS (currently 8). This will allow userspace apps to open a device file and run things like ibv_devinfo. Signed-off-by: Eli Cohen Signed-off-by: David S. Miller --- drivers/net/mlx4/pd.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/net/mlx4/pd.c') diff --git a/drivers/net/mlx4/pd.c b/drivers/net/mlx4/pd.c index 5210a0f31413..1286b886dcea 100644 --- a/drivers/net/mlx4/pd.c +++ b/drivers/net/mlx4/pd.c @@ -39,6 +39,10 @@ #include "mlx4.h" #include "icm.h" +enum { + MLX4_NUM_RESERVED_UARS = 8 +}; + int mlx4_pd_alloc(struct mlx4_dev *dev, u32 *pdn) { struct mlx4_priv *priv = mlx4_priv(dev); @@ -104,6 +108,10 @@ int mlx4_bf_alloc(struct mlx4_dev *dev, struct mlx4_bf *bf) if (!list_empty(&priv->bf_list)) uar = list_entry(priv->bf_list.next, struct mlx4_uar, bf_list); else { + if (mlx4_bitmap_avail(&priv->uar_table.bitmap) < MLX4_NUM_RESERVED_UARS) { + err = -ENOMEM; + goto out; + } uar = kmalloc(sizeof *uar, GFP_KERNEL); if (!uar) { err = -ENOMEM; -- cgit v1.2.3