[Intel-wired-lan] [PATCH iwl-next] ice: use DSN instead of PCI BDF for ice_adapter index

[Przemek Kitszel <przemyslaw.kitszel@intel.com>]

Use Device Serial Number instead of PCI bus/device/function for
index of struct ice_adapter.
Functions on the same physical device should point to the very same
ice_adapter instance.

This is not only simplification, but also fixes things up when PF
is passed to VM (and thus has a random BDF).

Suggested-by: Jacob Keller <jacob.e.keller@intel.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Suggested-by: Jiri Pirko <jiri@resnulli.us>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
---
CC: Karol Kolacinski <karol.kolacinski@intel.com>
CC: Grzegorz Nitka <grzegorz.nitka@intel.com>
CC: Michal Schmidt <mschmidt@redhat.com>
CC: Sergey Temerkhanov <sergey.temerkhanov@intel.com>
---
 drivers/net/ethernet/intel/ice/ice_adapter.h |  4 +--
 drivers/net/ethernet/intel/ice/ice_adapter.c | 29 +++-----------------
 2 files changed, 6 insertions(+), 27 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_adapter.h b/drivers/net/ethernet/intel/ice/ice_adapter.h
index e233225848b3..1935163bd32f 100644
--- a/drivers/net/ethernet/intel/ice/ice_adapter.h
+++ b/drivers/net/ethernet/intel/ice/ice_adapter.h
@@ -42,7 +42,7 @@ struct ice_adapter {
 	struct ice_port_list ports;
 };
 
-struct ice_adapter *ice_adapter_get(const struct pci_dev *pdev);
-void ice_adapter_put(const struct pci_dev *pdev);
+struct ice_adapter *ice_adapter_get(struct pci_dev *pdev);
+void ice_adapter_put(struct pci_dev *pdev);
 
 #endif /* _ICE_ADAPTER_H */
diff --git a/drivers/net/ethernet/intel/ice/ice_adapter.c b/drivers/net/ethernet/intel/ice/ice_adapter.c
index 01a08cfd0090..b668339ed0ef 100644
--- a/drivers/net/ethernet/intel/ice/ice_adapter.c
+++ b/drivers/net/ethernet/intel/ice/ice_adapter.c
@@ -1,7 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 // SPDX-FileCopyrightText: Copyright Red Hat
 
-#include <linux/bitfield.h>
 #include <linux/cleanup.h>
 #include <linux/mutex.h>
 #include <linux/pci.h>
@@ -14,29 +13,9 @@
 static DEFINE_XARRAY(ice_adapters);
 static DEFINE_MUTEX(ice_adapters_mutex);
 
-/* PCI bus number is 8 bits. Slot is 5 bits. Domain can have the rest. */
-#define INDEX_FIELD_DOMAIN GENMASK(BITS_PER_LONG - 1, 13)
-#define INDEX_FIELD_DEV    GENMASK(31, 16)
-#define INDEX_FIELD_BUS    GENMASK(12, 5)
-#define INDEX_FIELD_SLOT   GENMASK(4, 0)
-
-static unsigned long ice_adapter_index(const struct pci_dev *pdev)
+static unsigned long ice_adapter_index(struct pci_dev *pdev)
 {
-	unsigned int domain = pci_domain_nr(pdev->bus);
-
-	WARN_ON(domain > FIELD_MAX(INDEX_FIELD_DOMAIN));
-
-	switch (pdev->device) {
-	case ICE_DEV_ID_E825C_BACKPLANE:
-	case ICE_DEV_ID_E825C_QSFP:
-	case ICE_DEV_ID_E825C_SFP:
-	case ICE_DEV_ID_E825C_SGMII:
-		return FIELD_PREP(INDEX_FIELD_DEV, pdev->device);
-	default:
-		return FIELD_PREP(INDEX_FIELD_DOMAIN, domain) |
-		       FIELD_PREP(INDEX_FIELD_BUS,    pdev->bus->number) |
-		       FIELD_PREP(INDEX_FIELD_SLOT,   PCI_SLOT(pdev->devfn));
-	}
+	return (unsigned long)pci_get_dsn(pdev);
 }
 
 static struct ice_adapter *ice_adapter_new(void)
@@ -77,7 +56,7 @@ static void ice_adapter_free(struct ice_adapter *adapter)
  * Return:  Pointer to ice_adapter on success.
  *          ERR_PTR() on error. -ENOMEM is the only possible error.
  */
-struct ice_adapter *ice_adapter_get(const struct pci_dev *pdev)
+struct ice_adapter *ice_adapter_get(struct pci_dev *pdev)
 {
 	unsigned long index = ice_adapter_index(pdev);
 	struct ice_adapter *adapter;
@@ -110,7 +89,7 @@ struct ice_adapter *ice_adapter_get(const struct pci_dev *pdev)
  *
  * Context: Process, may sleep.
  */
-void ice_adapter_put(const struct pci_dev *pdev)
+void ice_adapter_put(struct pci_dev *pdev)
 {
 	unsigned long index = ice_adapter_index(pdev);
 	struct ice_adapter *adapter;
-- 
2.46.0