linux/arch/s390/pci/pci_bus.h
Niklas Schnelle 7dcfe50f58 s390/pci: rename get_zdev_by_bus() to zdev_from_bus()
Getting a zpci_dev via get_zdev_by_bus() uses the long lived reference
held in zbus->function[devfn]. This is accounted for in
pcibios_add_device() and pcibios_release_device().

Therefore there is no need to increment the reference count in
get_zdev_by_bus() as is done for get_zdev_by_fid(). Instead callers must
not access the device after pcibios_release_device() was called which is
necessary for common PCI code anyway. With this though the very similar
naming may be misleading so rename get_zdev_by_bus() to zdev_from_bus()
emphasizing that we are directly referencing the zdev via the bus.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-27 22:18:40 +02:00

44 lines
1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 2020
*
* Author(s):
* Pierre Morel <pmorel@linux.ibm.com>
*
*/
int zpci_bus_device_register(struct zpci_dev *zdev, struct pci_ops *ops);
void zpci_bus_device_unregister(struct zpci_dev *zdev);
int zpci_bus_scan_bus(struct zpci_bus *zbus);
void zpci_bus_scan_busses(void);
int zpci_bus_scan_device(struct zpci_dev *zdev);
void zpci_bus_remove_device(struct zpci_dev *zdev, bool set_error);
void zpci_release_device(struct kref *kref);
static inline void zpci_zdev_put(struct zpci_dev *zdev)
{
if (zdev)
kref_put(&zdev->kref, zpci_release_device);
}
static inline void zpci_zdev_get(struct zpci_dev *zdev)
{
kref_get(&zdev->kref);
}
int zpci_alloc_domain(int domain);
void zpci_free_domain(int domain);
int zpci_setup_bus_resources(struct zpci_dev *zdev,
struct list_head *resources);
static inline struct zpci_dev *zdev_from_bus(struct pci_bus *bus,
unsigned int devfn)
{
struct zpci_bus *zbus = bus->sysdata;
return (devfn >= ZPCI_FUNCTIONS_PER_BUS) ? NULL : zbus->function[devfn];
}