diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 658ac97..a196529 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -431,6 +431,11 @@ static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
 	if (bridge) {
 		INIT_LIST_HEAD(&bridge->windows);
 		bridge->bus = b;
+
+		/* Set minimal alignment shift of P2P bridges */
+		bridge->io_align_shift = PCI_DEFAULT_IO_ALIGN_SHIFT;
+		bridge->mem_align_shift = PCI_DEFAULT_MEM_ALIGN_SHIFT;
+		bridge->pmem_align_shift = PCI_DEFAULT_PMEM_ALIGN_SHIFT;
 	}
 
 	return bridge;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e66f4b2..2b2b38d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -376,9 +376,17 @@ struct pci_host_bridge_window {
 	resource_size_t offset;		/* bus address + offset = CPU address */
 };
 
+/* Default shits for P2P I/O and MMIO bar minimal alignment shifts */
+#define PCI_DEFAULT_IO_ALIGN_SHIFT	12	/* 4KB  */
+#define PCI_DEFAULT_MEM_ALIGN_SHIFT	20	/* 1MB  */
+#define PCI_DEFAULT_PMEM_ALIGN_SHIFT	20	/* 1MB */
+
 struct pci_host_bridge {
 	struct device dev;
 	struct pci_bus *bus;		/* root bus */
+	int io_align_shift;		/* P2P I/O bar minimal alignment shift  */
+	int mem_align_shift;		/* P2P MMIO bar minimal alignment shift */
+	int pmem_align_shift;		/* P2P prefetchable MMIO bar minimal alignment shift */
 	struct list_head windows;	/* pci_host_bridge_windows */
 	void (*release_fn)(struct pci_host_bridge *);
 	void *release_data;