iommu/amd: Use iommu_alloc_pages_node_sz() for the IRT

Use the actual size of the irq_table allocation, limiting to 128 due to
the HW alignment needs.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/22-v4-c8663abbb606+3f7-iommu_pages_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: jgunthorpe

drivers/iommu/amd/amd_iommu_types.h

@@ -314,6 +314,7 @@
 #define DTE_IRQ_REMAP_INTCTL    (2ULL << 60)
 #define DTE_IRQ_REMAP_ENABLE    1ULL
 
+#define DTE_INTTAB_ALIGNMENT    128
 #define DTE_INTTABLEN_MASK      (0xfULL << 1)
 #define DTE_INTTABLEN_VALUE_512 9ULL
 #define DTE_INTTABLEN_512       (DTE_INTTABLEN_VALUE_512 << 1)

drivers/iommu/amd/iommu.c

@@ -3129,15 +3129,16 @@ static struct irq_remap_table *get_irq_table(struct amd_iommu *iommu, u16 devid)
 	return table;
 }
 
-static struct irq_remap_table *__alloc_irq_table(int nid, int order)
+static struct irq_remap_table *__alloc_irq_table(int nid, size_t size)
 {
 	struct irq_remap_table *table;
 
 	table = kzalloc(sizeof(*table), GFP_KERNEL);
 	if (!table)
 		return NULL;
 
-	table->table = iommu_alloc_pages_node(nid, GFP_KERNEL, order);
+	table->table = iommu_alloc_pages_node_sz(
+		nid, GFP_KERNEL, max(DTE_INTTAB_ALIGNMENT, size));
 	if (!table->table) {
 		kfree(table);
 		return NULL;
@@ -3191,7 +3192,6 @@ static struct irq_remap_table *alloc_irq_table(struct amd_iommu *iommu,
 	struct irq_remap_table *new_table = NULL;
 	struct amd_iommu_pci_seg *pci_seg;
 	unsigned long flags;
-	int order = get_order(get_irq_table_size(max_irqs));
 	int nid = iommu && iommu->dev ? dev_to_node(&iommu->dev->dev) : NUMA_NO_NODE;
 	u16 alias;
 
@@ -3211,7 +3211,7 @@ static struct irq_remap_table *alloc_irq_table(struct amd_iommu *iommu,
 	spin_unlock_irqrestore(&iommu_table_lock, flags);
 
 	/* Nothing there yet, allocate new irq remapping table */
-	new_table = __alloc_irq_table(nid, order);
+	new_table = __alloc_irq_table(nid, get_irq_table_size(max_irqs));
 	if (!new_table)
 		return NULL;