iommu/vt-d: Separate page request queue from SVM

IO page faults are no longer dependent on CONFIG_INTEL_IOMMU_SVM. Move
all Page Request Queue (PRQ) functions that handle prq events to a new
file in drivers/iommu/intel/prq.c. The page_req_des struct is now
declared in drivers/iommu/intel/prq.c.

No functional changes are intended. This is a preparation patch to
enable the use of IO page faults outside the SVM/PASID use cases.

Signed-off-by: Joel Granados <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lu Baolu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>

Author: Joelgranados

drivers/iommu/intel/Makefile

@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_DMAR_TABLE) += dmar.o
-obj-$(CONFIG_INTEL_IOMMU) += iommu.o pasid.o nested.o cache.o
+obj-$(CONFIG_INTEL_IOMMU) += iommu.o pasid.o nested.o cache.o prq.o
 obj-$(CONFIG_DMAR_TABLE) += trace.o cap_audit.o
 obj-$(CONFIG_DMAR_PERF) += perf.o
 obj-$(CONFIG_INTEL_IOMMU_DEBUGFS) += debugfs.o

drivers/iommu/intel/iommu.c

@@ -1329,12 +1329,10 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
 	/* free context mapping */
 	free_context_table(iommu);
 
-#ifdef CONFIG_INTEL_IOMMU_SVM
 	if (pasid_supported(iommu)) {
 		if (ecap_prs(iommu->ecap))
-			intel_svm_finish_prq(iommu);
+			intel_iommu_finish_prq(iommu);
 	}
-#endif
 }
 
 /*
@@ -2194,19 +2192,18 @@ static int __init init_dmars(void)
 
 		iommu_flush_write_buffer(iommu);
 
-#ifdef CONFIG_INTEL_IOMMU_SVM
 		if (pasid_supported(iommu) && ecap_prs(iommu->ecap)) {
 			/*
 			 * Call dmar_alloc_hwirq() with dmar_global_lock held,
 			 * could cause possible lock race condition.
 			 */
 			up_write(&dmar_global_lock);
-			ret = intel_svm_enable_prq(iommu);
+			ret = intel_iommu_enable_prq(iommu);
 			down_write(&dmar_global_lock);
 			if (ret)
 				goto free_iommu;
 		}
-#endif
+
 		ret = dmar_set_interrupt(iommu);
 		if (ret)
 			goto free_iommu;
@@ -2619,13 +2616,12 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru)
 	intel_iommu_init_qi(iommu);
 	iommu_flush_write_buffer(iommu);
 
-#ifdef CONFIG_INTEL_IOMMU_SVM
 	if (pasid_supported(iommu) && ecap_prs(iommu->ecap)) {
-		ret = intel_svm_enable_prq(iommu);
+		ret = intel_iommu_enable_prq(iommu);
 		if (ret)
 			goto disable_iommu;
 	}
-#endif
+
 	ret = dmar_set_interrupt(iommu);
 	if (ret)
 		goto disable_iommu;
@@ -4072,7 +4068,7 @@ static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
 	intel_iommu_debugfs_remove_dev_pasid(dev_pasid);
 	kfree(dev_pasid);
 	intel_pasid_tear_down_entry(iommu, dev, pasid, false);
-	intel_drain_pasid_prq(dev, pasid);
+	intel_iommu_drain_pasid_prq(dev, pasid);
 }
 
 static int intel_iommu_set_dev_pasid(struct iommu_domain *domain,
@@ -4415,9 +4411,7 @@ const struct iommu_ops intel_iommu_ops = {
 	.def_domain_type	= device_def_domain_type,
 	.remove_dev_pasid	= intel_iommu_remove_dev_pasid,
 	.pgsize_bitmap		= SZ_4K,
-#ifdef CONFIG_INTEL_IOMMU_SVM
-	.page_response		= intel_svm_page_response,
-#endif
+	.page_response		= intel_iommu_page_response,
 	.default_domain_ops = &(const struct iommu_domain_ops) {
 		.attach_dev		= intel_iommu_attach_device,
 		.set_dev_pasid		= intel_iommu_set_dev_pasid,

drivers/iommu/intel/iommu.h

@@ -728,12 +728,10 @@ struct intel_iommu {
 
 	struct iommu_flush flush;
 #endif
-#ifdef CONFIG_INTEL_IOMMU_SVM
 	struct page_req_dsc *prq;
 	unsigned char prq_name[16];    /* Name for PRQ interrupt */
 	unsigned long prq_seq_number;
 	struct completion prq_complete;
-#endif
 	struct iopf_queue *iopf_queue;
 	unsigned char iopfq_name[16];
 	/* Synchronization between fault report and iommu device release. */
@@ -1274,18 +1272,18 @@ void intel_context_flush_present(struct device_domain_info *info,
 				 struct context_entry *context,
 				 u16 did, bool affect_domains);
 
+int intel_iommu_enable_prq(struct intel_iommu *iommu);
+int intel_iommu_finish_prq(struct intel_iommu *iommu);
+void intel_iommu_page_response(struct device *dev, struct iopf_fault *evt,
+			       struct iommu_page_response *msg);
+void intel_iommu_drain_pasid_prq(struct device *dev, u32 pasid);
+
 #ifdef CONFIG_INTEL_IOMMU_SVM
 void intel_svm_check(struct intel_iommu *iommu);
-int intel_svm_enable_prq(struct intel_iommu *iommu);
-int intel_svm_finish_prq(struct intel_iommu *iommu);
-void intel_svm_page_response(struct device *dev, struct iopf_fault *evt,
-			     struct iommu_page_response *msg);
 struct iommu_domain *intel_svm_domain_alloc(struct device *dev,
 					    struct mm_struct *mm);
-void intel_drain_pasid_prq(struct device *dev, u32 pasid);
 #else
 static inline void intel_svm_check(struct intel_iommu *iommu) {}
-static inline void intel_drain_pasid_prq(struct device *dev, u32 pasid) {}
 static inline struct iommu_domain *intel_svm_domain_alloc(struct device *dev,
 							  struct mm_struct *mm)
 {