PCI: endpoint: Replace spinlock with mutex

The pci_epc_ops is not intended to be invoked from interrupt context. Hence replace spin_lock_irqsave and spin_unlock_irqrestore with mutex_lock and mutex_unlock respectively.

Kishon Vijay Abraham I committed 6 years ago

Commit 3d3248d1 parent 5779dd02 files · +34 −54Browse files

Unified · Split

2 files

drivers/pci/endpoint/pci-epc-core.c +31 −51
include/linux/pci-epc.h +3 −3

drivers/pci/endpoint/pci-epc-core.c+31−51

 						    u8 func_no)
 {
 	const struct pci_epc_features *epc_features;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return NULL;
 	if (!epc->ops->get_features)
 		return NULL;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	epc_features = epc->ops->get_features(epc, func_no);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return epc_features;
 }
  */
 void pci_epc_stop(struct pci_epc *epc)
 {
-	unsigned long flags;
 	if (IS_ERR(epc) || !epc->ops->stop)
 		return;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	epc->ops->stop(epc);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_stop);
 int pci_epc_start(struct pci_epc *epc)
 {
 	int ret;
-	unsigned long flags;
 	if (IS_ERR(epc))
 		return -EINVAL;
 	if (!epc->ops->start)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->start(epc);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 		      enum pci_epc_irq_type type, u16 interrupt_num)
 {
 	int ret;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return -EINVAL;
 	if (!epc->ops->raise_irq)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->raise_irq(epc, func_no, type, interrupt_num);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 int pci_epc_get_msi(struct pci_epc *epc, u8 func_no)
 {
 	int interrupt;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return 0;
 	if (!epc->ops->get_msi)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	interrupt = epc->ops->get_msi(epc, func_no);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	if (interrupt < 0)
 		return 0;
 {
 	int ret;
 	u8 encode_int;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions ||
 	    interrupts > 32)
 	encode_int = order_base_2(interrupts);
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->set_msi(epc, func_no, encode_int);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 int pci_epc_get_msix(struct pci_epc *epc, u8 func_no)
 {
 	int interrupt;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return 0;
 	if (!epc->ops->get_msix)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	interrupt = epc->ops->get_msix(epc, func_no);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	if (interrupt < 0)
 		return 0;
 int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u16 interrupts)
 {
 	int ret;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions ||
 	    interrupts < 1 || interrupts > 2048)
 	if (!epc->ops->set_msix)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->set_msix(epc, func_no, interrupts - 1);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no,
 			phys_addr_t phys_addr)
 {
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return;
 	if (!epc->ops->unmap_addr)
 		return;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	epc->ops->unmap_addr(epc, func_no, phys_addr);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_unmap_addr);
 		     phys_addr_t phys_addr, u64 pci_addr, size_t size)
 {
 	int ret;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return -EINVAL;
 	if (!epc->ops->map_addr)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 void pci_epc_clear_bar(struct pci_epc *epc, u8 func_no,
 		       struct pci_epf_bar *epf_bar)
 {
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions ||
 	    (epf_bar->barno == BAR_5 &&
 	     epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64))
 	if (!epc->ops->clear_bar)
 		return;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	epc->ops->clear_bar(epc, func_no, epf_bar);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_clear_bar);
 		    struct pci_epf_bar *epf_bar)
 {
 	int ret;
-	unsigned long irq_flags;
 	int flags = epf_bar->flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions ||
 	if (!epc->ops->set_bar)
 		return 0;
-	spin_lock_irqsave(&epc->lock, irq_flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->set_bar(epc, func_no, epf_bar);
-	spin_unlock_irqrestore(&epc->lock, irq_flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
 			 struct pci_epf_header *header)
 {
 	int ret;
-	unsigned long flags;
 	if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions)
 		return -EINVAL;
 	if (!epc->ops->write_header)
 		return 0;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	ret = epc->ops->write_header(epc, func_no, header);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return ret;
 }
  */
 int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf)
 {
-	unsigned long flags;
 	if (epf->epc)
 		return -EBUSY;
 	epf->epc = epc;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	list_add_tail(&epf->list, &epc->pci_epf);
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 	return 0;
 }
  */
 void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf)
 {
-	unsigned long flags;
 	if (!epc || IS_ERR(epc) || !epf)
 		return;
-	spin_lock_irqsave(&epc->lock, flags);
+	mutex_lock(&epc->lock);
 	list_del(&epf->list);
 	epf->epc = NULL;
-	spin_unlock_irqrestore(&epc->lock, flags);
+	mutex_unlock(&epc->lock);
 }
 EXPORT_SYMBOL_GPL(pci_epc_remove_epf);
 		goto err_ret;
 	}
-	spin_lock_init(&epc->lock);
+	mutex_init(&epc->lock);
 	INIT_LIST_HEAD(&epc->pci_epf);
 	ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier);

include/linux/pci-epc.h+3−3

@@ -88,7 +88,7 @@ struct pci_epc_mem { · 87 unmodified lines
88	* @mem: address space of the endpoint controller	88	* @mem: address space of the endpoint controller
89	* @max_functions: max number of functions that can be configured in this EPC	89	* @max_functions: max number of functions that can be configured in this EPC
90	* @group: configfs group representing the PCI EPC device	90	* @group: configfs group representing the PCI EPC device
91	* @lock: spinlock to protect pci_epc ops	91	* @lock: mutex to protect pci_epc ops
92	* @notifier: used to notify EPF of any EPC events (like linkup)	92	* @notifier: used to notify EPF of any EPC events (like linkup)
93	*/	93	*/
94	struct pci_epc {	94	struct pci_epc {
@@ -98,8 +98,8 @@ struct pci_epc { · 3 unmodified lines
98	struct pci_epc_mem *mem;	98	struct pci_epc_mem *mem;
99	u8 max_functions;	99	u8 max_functions;
100	struct config_group *group;	100	struct config_group *group;
101	/* spinlock to protect against concurrent access of EP controller */	101	/* mutex to protect against concurrent access of EP controller */
102	spinlock_t lock;	102	struct mutex lock;
103	struct atomic_notifier_head notifier;	103	struct atomic_notifier_head notifier;
104	};	104	};
105		105

PCI: endpoint: Replace spinlock with mutex

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