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path: root/drivers/dca/dca-core.c
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Diffstat (limited to 'drivers/dca/dca-core.c')
-rw-r--r--drivers/dca/dca-core.c136
1 files changed, 111 insertions, 25 deletions
diff --git a/drivers/dca/dca-core.c b/drivers/dca/dca-core.c
index 52e6bb70a49..819dfda8823 100644
--- a/drivers/dca/dca-core.c
+++ b/drivers/dca/dca-core.c
@@ -27,6 +27,8 @@
#include <linux/notifier.h>
#include <linux/device.h>
#include <linux/dca.h>
+#include <linux/slab.h>
+#include <linux/module.h>
#define DCA_VERSION "1.12.1"
@@ -34,10 +36,14 @@ MODULE_VERSION(DCA_VERSION);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Intel Corporation");
-static DEFINE_SPINLOCK(dca_lock);
+static DEFINE_RAW_SPINLOCK(dca_lock);
static LIST_HEAD(dca_domains);
+static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
+
+static int dca_providers_blocked;
+
static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
@@ -69,6 +75,56 @@ static void dca_free_domain(struct dca_domain *domain)
kfree(domain);
}
+static int dca_provider_ioat_ver_3_0(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+
+ return ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
+ ((pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG0) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG1) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG2) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG3) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG4) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG5) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG6) ||
+ (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG7)));
+}
+
+static void unregister_dca_providers(void)
+{
+ struct dca_provider *dca, *_dca;
+ struct list_head unregistered_providers;
+ struct dca_domain *domain;
+ unsigned long flags;
+
+ blocking_notifier_call_chain(&dca_provider_chain,
+ DCA_PROVIDER_REMOVE, NULL);
+
+ INIT_LIST_HEAD(&unregistered_providers);
+
+ raw_spin_lock_irqsave(&dca_lock, flags);
+
+ if (list_empty(&dca_domains)) {
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+ return;
+ }
+
+ /* at this point only one domain in the list is expected */
+ domain = list_first_entry(&dca_domains, struct dca_domain, node);
+
+ list_for_each_entry_safe(dca, _dca, &domain->dca_providers, node)
+ list_move(&dca->node, &unregistered_providers);
+
+ dca_free_domain(domain);
+
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+ list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
+ dca_sysfs_remove_provider(dca);
+ list_del(&dca->node);
+ }
+}
+
static struct dca_domain *dca_find_domain(struct pci_bus *rc)
{
struct dca_domain *domain;
@@ -89,9 +145,8 @@ static struct dca_domain *dca_get_domain(struct device *dev)
domain = dca_find_domain(rc);
if (!domain) {
- domain = dca_allocate_domain(rc);
- if (domain)
- list_add(&domain->node, &dca_domains);
+ if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains))
+ dca_providers_blocked = 1;
}
return domain;
@@ -139,19 +194,19 @@ int dca_add_requester(struct device *dev)
if (!dev)
return -EFAULT;
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
/* check if the requester has not been added already */
dca = dca_find_provider_by_dev(dev);
if (dca) {
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return -EEXIST;
}
pci_rc = dca_pci_rc_from_dev(dev);
domain = dca_find_domain(pci_rc);
if (!domain) {
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return -ENODEV;
}
@@ -161,17 +216,17 @@ int dca_add_requester(struct device *dev)
break;
}
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
if (slot < 0)
return slot;
err = dca_sysfs_add_req(dca, dev, slot);
if (err) {
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
if (dca == dca_find_provider_by_dev(dev))
dca->ops->remove_requester(dca, dev);
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return err;
}
@@ -192,14 +247,14 @@ int dca_remove_requester(struct device *dev)
if (!dev)
return -EFAULT;
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
dca = dca_find_provider_by_dev(dev);
if (!dca) {
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return -ENODEV;
}
slot = dca->ops->remove_requester(dca, dev);
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
if (slot < 0)
return slot;
@@ -221,16 +276,16 @@ u8 dca_common_get_tag(struct device *dev, int cpu)
u8 tag;
unsigned long flags;
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
dca = dca_find_provider_by_dev(dev);
if (!dca) {
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return -ENODEV;
}
tag = dca->ops->get_tag(dca, dev, cpu);
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
return tag;
}
@@ -292,8 +347,6 @@ void free_dca_provider(struct dca_provider *dca)
}
EXPORT_SYMBOL_GPL(free_dca_provider);
-static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
-
/**
* register_dca_provider - register a dca provider
* @dca - struct created by alloc_dca_provider()
@@ -303,23 +356,51 @@ int register_dca_provider(struct dca_provider *dca, struct device *dev)
{
int err;
unsigned long flags;
- struct dca_domain *domain;
+ struct dca_domain *domain, *newdomain = NULL;
+
+ raw_spin_lock_irqsave(&dca_lock, flags);
+ if (dca_providers_blocked) {
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+ return -ENODEV;
+ }
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
err = dca_sysfs_add_provider(dca, dev);
if (err)
return err;
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
domain = dca_get_domain(dev);
if (!domain) {
- spin_unlock_irqrestore(&dca_lock, flags);
- return -ENODEV;
+ struct pci_bus *rc;
+
+ if (dca_providers_blocked) {
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+ dca_sysfs_remove_provider(dca);
+ unregister_dca_providers();
+ return -ENODEV;
+ }
+
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+ rc = dca_pci_rc_from_dev(dev);
+ newdomain = dca_allocate_domain(rc);
+ if (!newdomain)
+ return -ENODEV;
+ raw_spin_lock_irqsave(&dca_lock, flags);
+ /* Recheck, we might have raced after dropping the lock */
+ domain = dca_get_domain(dev);
+ if (!domain) {
+ domain = newdomain;
+ newdomain = NULL;
+ list_add(&domain->node, &dca_domains);
+ }
}
list_add(&dca->node, &domain->dca_providers);
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
blocking_notifier_call_chain(&dca_provider_chain,
DCA_PROVIDER_ADD, NULL);
+ kfree(newdomain);
return 0;
}
EXPORT_SYMBOL_GPL(register_dca_provider);
@@ -337,7 +418,12 @@ void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
blocking_notifier_call_chain(&dca_provider_chain,
DCA_PROVIDER_REMOVE, NULL);
- spin_lock_irqsave(&dca_lock, flags);
+ raw_spin_lock_irqsave(&dca_lock, flags);
+
+ if (list_empty(&dca_domains)) {
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
+ return;
+ }
list_del(&dca->node);
@@ -346,7 +432,7 @@ void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
if (list_empty(&domain->dca_providers))
dca_free_domain(domain);
- spin_unlock_irqrestore(&dca_lock, flags);
+ raw_spin_unlock_irqrestore(&dca_lock, flags);
dca_sysfs_remove_provider(dca);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-09 18:12:58 +0000