mlx4_core: Allocate and map sufficient ICM memory for EQ context

The current implementation allocates a single host page for EQ context
memory, which was OK when we only allocated a few EQs.  However, since
we now allocate an EQ for each CPU core, this patch removes the
hard-coded limit (which we exceed with 4 KB pages and 128 byte EQ
context entries with 32 CPUs) and uses the same ICM table code as all
other context tables, which ends up simplifying the code quite a bit
while fixing the problem.

This problem was actually hit in practice on a dual-socket Nehalem box
with 16 real hardware threads and sufficiently odd ACPI tables that it
shows on boot

    SMP: Allowing 32 CPUs, 16 hotplug CPUs

so num_possible_cpus() ends up 32, and mlx4 ends up creating 33 MSI-X
interrupts and 33 EQs.  This mlx4 bug means that mlx4 can't even
initialize at all on this quite mainstream system.

Cc: <stable@kernel.org>
Reported-by: Eli Cohen <eli@mellanox.co.il>
Tested-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/net/mlx4/eq.c

@@ -525,48 +525,6 @@ static void mlx4_unmap_clr_int(struct mlx4_dev *dev)
 	iounmap(priv->clr_base);
 }
 
-int mlx4_map_eq_icm(struct mlx4_dev *dev, u64 icm_virt)
-{
-	struct mlx4_priv *priv = mlx4_priv(dev);
-	int ret;
-
-	/*
-	 * We assume that mapping one page is enough for the whole EQ
-	 * context table.  This is fine with all current HCAs, because
-	 * we only use 32 EQs and each EQ uses 64 bytes of context
-	 * memory, or 1 KB total.
-	 */
-	priv->eq_table.icm_virt = icm_virt;
-	priv->eq_table.icm_page = alloc_page(GFP_HIGHUSER);
-	if (!priv->eq_table.icm_page)
-		return -ENOMEM;
-	priv->eq_table.icm_dma  = pci_map_page(dev->pdev, priv->eq_table.icm_page, 0,
-					       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
-	if (pci_dma_mapping_error(dev->pdev, priv->eq_table.icm_dma)) {
-		__free_page(priv->eq_table.icm_page);
-		return -ENOMEM;
-	}
-
-	ret = mlx4_MAP_ICM_page(dev, priv->eq_table.icm_dma, icm_virt);
-	if (ret) {
-		pci_unmap_page(dev->pdev, priv->eq_table.icm_dma, PAGE_SIZE,
-			       PCI_DMA_BIDIRECTIONAL);
-		__free_page(priv->eq_table.icm_page);
-	}
-
-	return ret;
-}
-
-void mlx4_unmap_eq_icm(struct mlx4_dev *dev)
-{
-	struct mlx4_priv *priv = mlx4_priv(dev);
-
-	mlx4_UNMAP_ICM(dev, priv->eq_table.icm_virt, 1);
-	pci_unmap_page(dev->pdev, priv->eq_table.icm_dma, PAGE_SIZE,
-		       PCI_DMA_BIDIRECTIONAL);
-	__free_page(priv->eq_table.icm_page);
-}
-
 int mlx4_alloc_eq_table(struct mlx4_dev *dev)
 {
 	struct mlx4_priv *priv = mlx4_priv(dev);

drivers/net/mlx4/main.c

@@ -525,7 +525,10 @@ static int mlx4_init_icm(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap,
 		goto err_unmap_aux;
 	}
 
-	err = mlx4_map_eq_icm(dev, init_hca->eqc_base);
+	err = mlx4_init_icm_table(dev, &priv->eq_table.table,
+				  init_hca->eqc_base, dev_cap->eqc_entry_sz,
+				  dev->caps.num_eqs, dev->caps.num_eqs,
+				  0, 0);
 	if (err) {
 		mlx4_err(dev, "Failed to map EQ context memory, aborting.\n");
 		goto err_unmap_cmpt;
@@ -668,7 +671,7 @@ err_unmap_mtt:
 	mlx4_cleanup_icm_table(dev, &priv->mr_table.mtt_table);
 
 err_unmap_eq:
-	mlx4_unmap_eq_icm(dev);
+	mlx4_cleanup_icm_table(dev, &priv->eq_table.table);
 
 err_unmap_cmpt:
 	mlx4_cleanup_icm_table(dev, &priv->eq_table.cmpt_table);
@@ -698,11 +701,11 @@ static void mlx4_free_icms(struct mlx4_dev *dev)
 	mlx4_cleanup_icm_table(dev, &priv->qp_table.qp_table);
 	mlx4_cleanup_icm_table(dev, &priv->mr_table.dmpt_table);
 	mlx4_cleanup_icm_table(dev, &priv->mr_table.mtt_table);
+	mlx4_cleanup_icm_table(dev, &priv->eq_table.table);
 	mlx4_cleanup_icm_table(dev, &priv->eq_table.cmpt_table);
 	mlx4_cleanup_icm_table(dev, &priv->cq_table.cmpt_table);
 	mlx4_cleanup_icm_table(dev, &priv->srq_table.cmpt_table);
 	mlx4_cleanup_icm_table(dev, &priv->qp_table.cmpt_table);
-	mlx4_unmap_eq_icm(dev);
 
 	mlx4_UNMAP_ICM_AUX(dev);
 	mlx4_free_icm(dev, priv->fw.aux_icm, 0);

drivers/net/mlx4/mlx4.h

@@ -205,9 +205,7 @@ struct mlx4_eq_table {
 	void __iomem	      **uar_map;
 	u32			clr_mask;
 	struct mlx4_eq	       *eq;
-	u64			icm_virt;
-	struct page	       *icm_page;
-	dma_addr_t		icm_dma;
+	struct mlx4_icm_table	table;
 	struct mlx4_icm_table	cmpt_table;
 	int			have_irq;
 	u8			inta_pin;
@@ -373,9 +371,6 @@ u64 mlx4_make_profile(struct mlx4_dev *dev,
 		      struct mlx4_dev_cap *dev_cap,
 		      struct mlx4_init_hca_param *init_hca);
 
-int mlx4_map_eq_icm(struct mlx4_dev *dev, u64 icm_virt);
-void mlx4_unmap_eq_icm(struct mlx4_dev *dev);
-
 int mlx4_cmd_init(struct mlx4_dev *dev);
 void mlx4_cmd_cleanup(struct mlx4_dev *dev);
 void mlx4_cmd_event(struct mlx4_dev *dev, u16 token, u8 status, u64 out_param);