RDMA/usnic: Refactor usnic_uiom_alloc_pd()

Rather than hard-coding pci_bus_type, pass the PF device through to
usnic_uiom_alloc_pd() and retrieve its bus there. This prepares for
iommu_domain_alloc() changing to take a device rather than a bus_type.

Link: https://lore.kernel.org/r/ef607cb3f5a09920b86971b8c8e60af8c647457e.1649169359.git.robin.murphy@arm.comSigned-off-by: Robin Murphy <robin.murphy@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/usnic/usnic_ib_verbs.c

@@ -443,7 +443,7 @@ int usnic_ib_alloc_pd(struct ib_pd *ibpd, struct ib_udata *udata)
 {
 	struct usnic_ib_pd *pd = to_upd(ibpd);
 
-	pd->umem_pd = usnic_uiom_alloc_pd();
+	pd->umem_pd = usnic_uiom_alloc_pd(ibpd->device->dev.parent);
 	if (IS_ERR(pd->umem_pd))
 		return PTR_ERR(pd->umem_pd);
 
@@ -707,4 +707,3 @@ int usnic_ib_mmap(struct ib_ucontext *context,
 	usnic_err("No VF %u found\n", vfid);
 	return -EINVAL;
 }
-

drivers/infiniband/hw/usnic/usnic_uiom.c

@@ -40,7 +40,6 @@
 #include <linux/iommu.h>
 #include <linux/workqueue.h>
 #include <linux/list.h>
-#include <linux/pci.h>
 #include <rdma/ib_verbs.h>
 
 #include "usnic_log.h"
@@ -439,7 +438,7 @@ void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr)
 	__usnic_uiom_release_tail(uiomr);
 }
 
-struct usnic_uiom_pd *usnic_uiom_alloc_pd(void)
+struct usnic_uiom_pd *usnic_uiom_alloc_pd(struct device *dev)
 {
 	struct usnic_uiom_pd *pd;
 	void *domain;
@@ -448,7 +447,7 @@ struct usnic_uiom_pd *usnic_uiom_alloc_pd(void)
 	if (!pd)
 		return ERR_PTR(-ENOMEM);
 
-	pd->domain = domain = iommu_domain_alloc(&pci_bus_type);
+	pd->domain = domain = iommu_domain_alloc(dev->bus);
 	if (!domain) {
 		usnic_err("Failed to allocate IOMMU domain");
 		kfree(pd);

drivers/infiniband/hw/usnic/usnic_uiom.h

@@ -80,7 +80,7 @@ struct usnic_uiom_chunk {
 	struct scatterlist		page_list[];
 };
 
-struct usnic_uiom_pd *usnic_uiom_alloc_pd(void);
+struct usnic_uiom_pd *usnic_uiom_alloc_pd(struct device *dev);
 void usnic_uiom_dealloc_pd(struct usnic_uiom_pd *pd);
 int usnic_uiom_attach_dev_to_pd(struct usnic_uiom_pd *pd, struct device *dev);
 void usnic_uiom_detach_dev_from_pd(struct usnic_uiom_pd *pd,