[PATCH v4 5/5] PCI: endpoint: Use link_up() callback in place of LINK_UP notifier

From: Manivannan Sadhasivam
Date: Tue Oct 25 2022 - 10:51:56 EST


As a part of the transition towards callback mechanism for signalling the
events from EPC to EPF, let's use the link_up() callback in the place of
the LINK_UP notifier. This also removes the notifier support completely
from the PCI endpoint framework.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/pci/endpoint/functions/pci-epf-test.c | 33 ++++++-------------
drivers/pci/endpoint/pci-epc-core.c | 12 +++++--
include/linux/pci-epc.h | 8 -----
include/linux/pci-epf.h | 8 ++---
4 files changed, 22 insertions(+), 39 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
index 868de17e1ad2..f75045f2dee3 100644
--- a/drivers/pci/endpoint/functions/pci-epf-test.c
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -826,30 +826,21 @@ static int pci_epf_test_core_init(struct pci_epf *epf)
return 0;
}

-static const struct pci_epc_event_ops pci_epf_test_event_ops = {
- .core_init = pci_epf_test_core_init,
-};
-
-static int pci_epf_test_notifier(struct notifier_block *nb, unsigned long val,
- void *data)
+int pci_epf_test_link_up(struct pci_epf *epf)
{
- struct pci_epf *epf = container_of(nb, struct pci_epf, nb);
struct pci_epf_test *epf_test = epf_get_drvdata(epf);

- switch (val) {
- case LINK_UP:
- queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
- msecs_to_jiffies(1));
- break;
-
- default:
- dev_err(&epf->dev, "Invalid EPF test notifier event\n");
- return NOTIFY_BAD;
- }
+ queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
+ msecs_to_jiffies(1));

- return NOTIFY_OK;
+ return 0;
}

+static const struct pci_epc_event_ops pci_epf_test_event_ops = {
+ .core_init = pci_epf_test_core_init,
+ .link_up = pci_epf_test_link_up,
+};
+
static int pci_epf_test_alloc_space(struct pci_epf *epf)
{
struct pci_epf_test *epf_test = epf_get_drvdata(epf);
@@ -976,12 +967,8 @@ static int pci_epf_test_bind(struct pci_epf *epf)
if (ret)
epf_test->dma_supported = false;

- if (linkup_notifier || core_init_notifier) {
- epf->nb.notifier_call = pci_epf_test_notifier;
- pci_epc_register_notifier(epc, &epf->nb);
- } else {
+ if (!linkup_notifier && !core_init_notifier)
queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
- }

return 0;
}
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index 8bb60528f530..c0954fddcc14 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -690,10 +690,19 @@ EXPORT_SYMBOL_GPL(pci_epc_remove_epf);
*/
void pci_epc_linkup(struct pci_epc *epc)
{
+ struct pci_epf *epf;
+
if (!epc || IS_ERR(epc))
return;

- atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL);
+ mutex_lock(&epc->list_lock);
+ list_for_each_entry(epf, &epc->pci_epf, list) {
+ mutex_lock(&epf->lock);
+ if (epf->event_ops && epf->event_ops->link_up)
+ epf->event_ops->link_up(epf);
+ mutex_unlock(&epf->lock);
+ }
+ mutex_unlock(&epc->list_lock);
}
EXPORT_SYMBOL_GPL(pci_epc_linkup);

@@ -784,7 +793,6 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
mutex_init(&epc->lock);
mutex_init(&epc->list_lock);
INIT_LIST_HEAD(&epc->pci_epf);
- ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier);

device_initialize(&epc->dev);
epc->dev.class = pci_epc_class;
diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index fe729dfe509b..301bb0e53707 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -135,7 +135,6 @@ struct pci_epc_mem {
* @group: configfs group representing the PCI EPC device
* @lock: mutex to protect pci_epc ops
* @function_num_map: bitmap to manage physical function number
- * @notifier: used to notify EPF of any EPC events (like linkup)
*/
struct pci_epc {
struct device dev;
@@ -151,7 +150,6 @@ struct pci_epc {
/* mutex to protect against concurrent access of EP controller */
struct mutex lock;
unsigned long function_num_map;
- struct atomic_notifier_head notifier;
};

/**
@@ -194,12 +192,6 @@ static inline void *epc_get_drvdata(struct pci_epc *epc)
return dev_get_drvdata(&epc->dev);
}

-static inline int
-pci_epc_register_notifier(struct pci_epc *epc, struct notifier_block *nb)
-{
- return atomic_notifier_chain_register(&epc->notifier, nb);
-}
-
struct pci_epc *
__devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops,
struct module *owner);
diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
index a06f3b4c8bee..bc613f0df7e3 100644
--- a/include/linux/pci-epf.h
+++ b/include/linux/pci-epf.h
@@ -17,10 +17,6 @@
struct pci_epf;
enum pci_epc_interface_type;

-enum pci_notify_event {
- LINK_UP,
-};
-
enum pci_barno {
NO_BAR = -1,
BAR_0,
@@ -74,9 +70,11 @@ struct pci_epf_ops {
/**
* struct pci_epf_event_ops - Callbacks for capturing the EPC events
* @core_init: Callback for the EPC initialization complete event
+ * @link_up: Callback for the EPC link up event
*/
struct pci_epc_event_ops {
int (*core_init)(struct pci_epf *epf);
+ int (*link_up)(struct pci_epf *epf);
};

/**
@@ -135,7 +133,6 @@ struct pci_epf_bar {
* @driver: the EPF driver to which this EPF device is bound
* @id: Pointer to the EPF device ID
* @list: to add pci_epf as a list of PCI endpoint functions to pci_epc
- * @nb: notifier block to notify EPF of any EPC events (like linkup)
* @lock: mutex to protect pci_epf_ops
* @sec_epc: the secondary EPC device to which this EPF device is bound
* @sec_epc_list: to add pci_epf as list of PCI endpoint functions to secondary
@@ -164,7 +161,6 @@ struct pci_epf {
struct pci_epf_driver *driver;
const struct pci_epf_device_id *id;
struct list_head list;
- struct notifier_block nb;
/* mutex to protect against concurrent access of pci_epf_ops */
struct mutex lock;

--
2.25.1