Commit e4728eed authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by Bjorn Helgaas
Browse files

PCI: Add pci_resource_num() helper 

A few places in PCI code, mainly in setup-bus.c, need to reverse lookup the
index of a resource in pci_dev's resource array. Create pci_resource_num()
helper to avoid repeating the pointer arithmetic trick used to calculate
the index.

Link: https://lore.kernel.org/r/20241216175632.4175-11-ilpo.jarvinen@linux.intel.com


Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Tested-by: default avatarXiaochun Lee <lixc17@lenovo.com>
parent 2bd0c721

drivers/pci/pci.h

+23 −1
Original line number Diff line number Diff line
@@ -334,6 +334,28 @@ void pci_walk_bus_locked(struct pci_bus *top, 


const char *pci_resource_name(struct pci_dev *dev, unsigned int i);



/**

 * pci_resource_num - Reverse lookup resource number from device resources

 * @dev: PCI device

 * @res: Resource to lookup index for (MUST be a @dev's resource)

 *

 * Perform reverse lookup to determine the resource number for @res within

 * @dev resource array. NOTE: The caller is responsible for ensuring @res is

 * among @dev's resources!

 *

 * Returns: resource number.

 */

static inline int pci_resource_num(const struct pci_dev *dev,

				   const struct resource *res)

{

	int resno = res - &dev->resource[0];



	/* Passing a resource that is not among dev's resources? */

	WARN_ON_ONCE(resno >= PCI_NUM_RESOURCES);



	return resno;

}



void pci_reassigndev_resource_alignment(struct pci_dev *dev);

void pci_disable_bridge_window(struct pci_dev *dev);

struct pci_bus *pci_bus_get(struct pci_bus *bus);
@@ -693,7 +715,7 @@ unsigned long pci_cardbus_resource_alignment(struct resource *); 
static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,

						     struct resource *res)

{

	int resno = res - dev->resource;

	int resno = pci_resource_num(dev, res);



	if (pci_resource_is_iov(resno))

		return pci_sriov_resource_alignment(dev, resno);

drivers/pci/setup-bus.c

+5 −5
Original line number Diff line number Diff line
@@ -242,7 +242,7 @@ static void reassign_resources_sorted(struct list_head *realloc_head, 
		if (!found_match) /* Just skip */

			continue;



		idx = res - &add_res->dev->resource[0];

		idx = pci_resource_num(add_res->dev, res);

		res_name = pci_resource_name(add_res->dev, idx);

		add_size = add_res->add_size;

		align = add_res->min_align;
@@ -284,7 +284,7 @@ static void assign_requested_resources_sorted(struct list_head *head, 


	list_for_each_entry(dev_res, head, list) {

		res = dev_res->res;

		idx = res - &dev_res->dev->resource[0];

		idx = pci_resource_num(dev_res->dev, res);



		if (!resource_size(res))

			continue;
@@ -2210,7 +2210,7 @@ void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus) 
		res->flags = fail_res->flags;



		if (pci_is_bridge(fail_res->dev)) {

			idx = res - &fail_res->dev->resource[0];

			idx = pci_resource_num(fail_res->dev, res);

			if (idx >= PCI_BRIDGE_RESOURCES &&

			    idx <= PCI_BRIDGE_RESOURCE_END)

				res->flags = 0;
@@ -2294,7 +2294,7 @@ void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge) 
		res->flags = fail_res->flags;



		if (pci_is_bridge(fail_res->dev)) {

			idx = res - &fail_res->dev->resource[0];

			idx = pci_resource_num(fail_res->dev, res);

			if (idx >= PCI_BRIDGE_RESOURCES &&

			    idx <= PCI_BRIDGE_RESOURCE_END)

				res->flags = 0;
@@ -2401,7 +2401,7 @@ int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type) 
		struct resource *res = dev_res->res;



		bridge = dev_res->dev;

		i = res - bridge->resource;

		i = pci_resource_num(bridge, res);



		res->start = dev_res->start;

		res->end = dev_res->end;