From 6296883ca4cd52dafb45f191d24102e28ded38f2 Mon Sep 17 00:00:00 2001 From: Yevgeny Petrilin Date: Wed, 23 Apr 2008 11:55:45 -0700 Subject: mlx4_core: Move kernel doorbell management into core In addition to mlx4_ib, there will be ethernet and FC consumers of mlx4_core, so move the code for managing kernel doorbells into the core module to avoid having to duplicate this multiple times. Signed-off-by: Yevgeny Petrilin Signed-off-by: Roland Dreier --- drivers/net/mlx4/alloc.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 111 insertions(+) (limited to 'drivers/net/mlx4/alloc.c') diff --git a/drivers/net/mlx4/alloc.c b/drivers/net/mlx4/alloc.c index 75ef9d0d974d..43c6d04bb880 100644 --- a/drivers/net/mlx4/alloc.c +++ b/drivers/net/mlx4/alloc.c @@ -196,3 +196,114 @@ void mlx4_buf_free(struct mlx4_dev *dev, int size, struct mlx4_buf *buf) } } EXPORT_SYMBOL_GPL(mlx4_buf_free); + +static struct mlx4_db_pgdir *mlx4_alloc_db_pgdir(struct device *dma_device) +{ + struct mlx4_db_pgdir *pgdir; + + pgdir = kzalloc(sizeof *pgdir, GFP_KERNEL); + if (!pgdir) + return NULL; + + bitmap_fill(pgdir->order1, MLX4_DB_PER_PAGE / 2); + pgdir->bits[0] = pgdir->order0; + pgdir->bits[1] = pgdir->order1; + pgdir->db_page = dma_alloc_coherent(dma_device, PAGE_SIZE, + &pgdir->db_dma, GFP_KERNEL); + if (!pgdir->db_page) { + kfree(pgdir); + return NULL; + } + + return pgdir; +} + +static int mlx4_alloc_db_from_pgdir(struct mlx4_db_pgdir *pgdir, + struct mlx4_db *db, int order) +{ + int o; + int i; + + for (o = order; o <= 1; ++o) { + i = find_first_bit(pgdir->bits[o], MLX4_DB_PER_PAGE >> o); + if (i < MLX4_DB_PER_PAGE >> o) + goto found; + } + + return -ENOMEM; + +found: + clear_bit(i, pgdir->bits[o]); + + i <<= o; + + if (o > order) + set_bit(i ^ 1, pgdir->bits[order]); + + db->u.pgdir = pgdir; + db->index = i; + db->db = pgdir->db_page + db->index; + db->dma = pgdir->db_dma + db->index * 4; + db->order = order; + + return 0; +} + +int mlx4_db_alloc(struct mlx4_dev *dev, struct mlx4_db *db, int order) +{ + struct mlx4_priv *priv = mlx4_priv(dev); + struct mlx4_db_pgdir *pgdir; + int ret = 0; + + mutex_lock(&priv->pgdir_mutex); + + list_for_each_entry(pgdir, &priv->pgdir_list, list) + if (!mlx4_alloc_db_from_pgdir(pgdir, db, order)) + goto out; + + pgdir = mlx4_alloc_db_pgdir(&(dev->pdev->dev)); + if (!pgdir) { + ret = -ENOMEM; + goto out; + } + + list_add(&pgdir->list, &priv->pgdir_list); + + /* This should never fail -- we just allocated an empty page: */ + WARN_ON(mlx4_alloc_db_from_pgdir(pgdir, db, order)); + +out: + mutex_unlock(&priv->pgdir_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(mlx4_db_alloc); + +void mlx4_db_free(struct mlx4_dev *dev, struct mlx4_db *db) +{ + struct mlx4_priv *priv = mlx4_priv(dev); + int o; + int i; + + mutex_lock(&priv->pgdir_mutex); + + o = db->order; + i = db->index; + + if (db->order == 0 && test_bit(i ^ 1, db->u.pgdir->order0)) { + clear_bit(i ^ 1, db->u.pgdir->order0); + ++o; + } + i >>= o; + set_bit(i, db->u.pgdir->bits[o]); + + if (bitmap_full(db->u.pgdir->order1, MLX4_DB_PER_PAGE / 2)) { + dma_free_coherent(&(dev->pdev->dev), PAGE_SIZE, + db->u.pgdir->db_page, db->u.pgdir->db_dma); + list_del(&db->u.pgdir->list); + kfree(db->u.pgdir); + } + + mutex_unlock(&priv->pgdir_mutex); +} +EXPORT_SYMBOL_GPL(mlx4_db_free); -- cgit v1.2.3