@@ -32,17 +32,19 @@ struct ice_port_list {
* @refcount: Reference count. struct ice_pf objects hold the references.
* @ctrl_pf: Control PF of the adapter
* @ports: Ports list
+ * @device_serial_number: DSN cached for collision detection on 32bit systems
*/
struct ice_adapter {
refcount_t refcount;
/* For access to the GLTSYN_TIME register */
spinlock_t ptp_gltsyn_time_lock;
struct ice_pf *ctrl_pf;
struct ice_port_list ports;
+ u64 device_serial_number;
};
-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 */
@@ -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>
@@ -14,39 +13,24 @@
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(u64 dsn)
{
- 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));
- }
+#if BITS_PER_LONG == 64
+ return dsn;
+#else
+ return (u32)dsn ^ (u32)(dsn >> 32);
+#endif
}
-static struct ice_adapter *ice_adapter_new(void)
+static struct ice_adapter *ice_adapter_new(u64 dsn)
{
struct ice_adapter *adapter;
adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
if (!adapter)
return NULL;
+ adapter->device_serial_number = dsn;
spin_lock_init(&adapter->ptp_gltsyn_time_lock);
refcount_set(&adapter->refcount, 1);
@@ -77,23 +61,26 @@ 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);
+ u64 dsn = pci_get_dsn(pdev);
struct ice_adapter *adapter;
+ unsigned long index;
int err;
+ index = ice_adapter_index(dsn);
scoped_guard(mutex, &ice_adapters_mutex) {
err = xa_insert(&ice_adapters, index, NULL, GFP_KERNEL);
if (err == -EBUSY) {
adapter = xa_load(&ice_adapters, index);
refcount_inc(&adapter->refcount);
+ WARN_ON_ONCE(adapter->device_serial_number != dsn);
return adapter;
}
if (err)
return ERR_PTR(err);
- adapter = ice_adapter_new();
+ adapter = ice_adapter_new(dsn);
if (!adapter)
return ERR_PTR(-ENOMEM);
xa_store(&ice_adapters, index, adapter, GFP_KERNEL);
@@ -110,11 +97,13 @@ 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);
+ u64 dsn = pci_get_dsn(pdev);
struct ice_adapter *adapter;
+ unsigned long index;
+ index = ice_adapter_index(dsn);
scoped_guard(mutex, &ice_adapters_mutex) {
adapter = xa_load(&ice_adapters, index);
if (WARN_ON(!adapter))
Use Device Serial Number instead of PCI bus/device/function for the index of struct ice_adapter. Functions on the same physical device should point to the very same ice_adapter instance, but with two PFs, when at least one of them is PCI-e passed-through to a VM, it is no longer the case - PFs will get seemingly random PCI BDF values, and thus indices, what finally leds to each of them being on their own instance of ice_adapter. That causes them to don't attempt any synchronization of the PTP HW clock usage, or any other future resources. DSN works nicely in place of the index, as it is "immutable" in terms of virtualization. Fixes: 0e2bddf9e5f9 ("ice: add ice_adapter for shared data across PFs on the same NIC") 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> CC: Michal Kubiak <michal.kubiak@intel.com> CC: Simon Horman <horms@kernel.org> v4: - Add fixes tag for real... (Simon) - extend commit message (Simon) - pass dsn to ice_adapter_new() to have simpler code (I happened to do that as (local) followup) (me) v3: https://lore.kernel.org/intel-wired-lan/20250408134655.4287-1-przemyslaw.kitszel@intel.com/ - Add fixes tag (Michal K) - add missing braces (lkp bot), turns out it's hard to purge C++ from your mind - (no changes in the collision handling on 32bit systems) v2: https://lore.kernel.org/intel-wired-lan/20250407112005.85468-1-przemyslaw.kitszel@intel.com/ - target to -net (Jiri) - mix both halves of u64 DSN on 32bit systems (Jiri) - (no changes in terms of fallbacks for pre-prod HW) - warn when there is DSN collision after reducing to 32bit v1: https://lore.kernel.org/netdev/20250306211159.3697-2-przemyslaw.kitszel@intel.com --- drivers/net/ethernet/intel/ice/ice_adapter.h | 6 ++- drivers/net/ethernet/intel/ice/ice_adapter.c | 47 ++++++++------------ 2 files changed, 22 insertions(+), 31 deletions(-)