1 files changed, 259 insertions, 68 deletions

diff --git a/arch/arm64/kvm/vgic/vgic-debug.c b/arch/arm64/kvm/vgic/vgic-debug.c
index afb018528bc3..8046f9e9719b 100644
--- a/arch/arm64/kvm/vgic/vgic-debug.c
+++ b/arch/arm64/kvm/vgic/vgic-debug.c
@@ -25,11 +25,9 @@
 struct vgic_state_iter {
 	int nr_cpus;
 	int nr_spis;
-	int nr_lpis;
 	int dist_id;
 	int vcpu_id;
 	unsigned long intid;
-	int lpi_idx;
 };
 
 static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
@@ -45,13 +43,15 @@ static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
 	 * Let the xarray drive the iterator after the last SPI, as the iterator
 	 * has exhausted the sequentially-allocated INTID space.
 	 */
-	if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1) &&
-	    iter->nr_lpis) {
-		if (iter->lpi_idx < iter->nr_lpis)
-			xa_find_after(&dist->lpi_xa, &iter->intid,
-				      VGIC_LPI_MAX_INTID,
-				      LPI_XA_MARK_DEBUG_ITER);
-		iter->lpi_idx++;
+	if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1)) {
+		if (iter->intid == VGIC_LPI_MAX_INTID + 1)
+			return;
+
+		rcu_read_lock();
+		if (!xa_find_after(&dist->lpi_xa, &iter->intid,
+				   VGIC_LPI_MAX_INTID, XA_PRESENT))
+			iter->intid = VGIC_LPI_MAX_INTID + 1;
+		rcu_read_unlock();
 		return;
 	}
 
@@ -61,36 +61,21 @@ static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
 		iter->intid = 0;
 }
 
-static int iter_mark_lpis(struct kvm *kvm)
+static int vgic_count_lpis(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
 	struct vgic_irq *irq;
 	unsigned long intid;
 	int nr_lpis = 0;
 
-	xa_for_each(&dist->lpi_xa, intid, irq) {
-		if (!vgic_try_get_irq_kref(irq))
-			continue;
-
-		xa_set_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
+	rcu_read_lock();
+	xa_for_each(&dist->lpi_xa, intid, irq)
 		nr_lpis++;
-	}
+	rcu_read_unlock();
 
 	return nr_lpis;
 }
 
-static void iter_unmark_lpis(struct kvm *kvm)
-{
-	struct vgic_dist *dist = &kvm->arch.vgic;
-	struct vgic_irq *irq;
-	unsigned long intid;
-
-	xa_for_each_marked(&dist->lpi_xa, intid, irq, LPI_XA_MARK_DEBUG_ITER) {
-		xa_clear_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
-		vgic_put_irq(kvm, irq);
-	}
-}
-
 static void iter_init(struct kvm *kvm, struct vgic_state_iter *iter,
 		      loff_t pos)
 {
@@ -100,8 +85,6 @@ static void iter_init(struct kvm *kvm, struct vgic_state_iter *iter,
 
 	iter->nr_cpus = nr_cpus;
 	iter->nr_spis = kvm->arch.vgic.nr_spis;
-	if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
-		iter->nr_lpis = iter_mark_lpis(kvm);
 
 	/* Fast forward to the right position if needed */
 	while (pos--)
@@ -113,7 +96,7 @@ static bool end_of_vgic(struct vgic_state_iter *iter)
 	return iter->dist_id > 0 &&
 		iter->vcpu_id == iter->nr_cpus &&
 		iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS) &&
-		(!iter->nr_lpis || iter->lpi_idx > iter->nr_lpis);
+		iter->intid > VGIC_LPI_MAX_INTID;
 }
 
 static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
@@ -121,72 +104,56 @@ static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
 	struct kvm *kvm = s->private;
 	struct vgic_state_iter *iter;
 
-	mutex_lock(&kvm->arch.config_lock);
-	iter = kvm->arch.vgic.iter;
-	if (iter) {
-		iter = ERR_PTR(-EBUSY);
-		goto out;
-	}
-
-	iter = kmalloc(sizeof(*iter), GFP_KERNEL);
-	if (!iter) {
-		iter = ERR_PTR(-ENOMEM);
-		goto out;
-	}
+	iter = kmalloc_obj(*iter);
+	if (!iter)
+		return ERR_PTR(-ENOMEM);
 
 	iter_init(kvm, iter, *pos);
-	kvm->arch.vgic.iter = iter;
 
-	if (end_of_vgic(iter))
+	if (end_of_vgic(iter)) {
+		kfree(iter);
 		iter = NULL;
-out:
-	mutex_unlock(&kvm->arch.config_lock);
+	}
+
 	return iter;
 }
 
 static void *vgic_debug_next(struct seq_file *s, void *v, loff_t *pos)
 {
 	struct kvm *kvm = s->private;
-	struct vgic_state_iter *iter = kvm->arch.vgic.iter;
+	struct vgic_state_iter *iter = v;
 
 	++*pos;
 	iter_next(kvm, iter);
-	if (end_of_vgic(iter))
+	if (end_of_vgic(iter)) {
+		kfree(iter);
 		iter = NULL;
+	}
 	return iter;
 }
 
 static void vgic_debug_stop(struct seq_file *s, void *v)
 {
-	struct kvm *kvm = s->private;
-	struct vgic_state_iter *iter;
+	struct vgic_state_iter *iter = v;
 
-	/*
-	 * If the seq file wasn't properly opened, there's nothing to clearn
-	 * up.
-	 */
-	if (IS_ERR(v))
+	if (IS_ERR_OR_NULL(v))
 		return;
 
-	mutex_lock(&kvm->arch.config_lock);
-	iter = kvm->arch.vgic.iter;
-	iter_unmark_lpis(kvm);
 	kfree(iter);
-	kvm->arch.vgic.iter = NULL;
-	mutex_unlock(&kvm->arch.config_lock);
 }
 
 static void print_dist_state(struct seq_file *s, struct vgic_dist *dist,
 			     struct vgic_state_iter *iter)
 {
 	bool v3 = dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3;
+	struct kvm *kvm = s->private;
 
 	seq_printf(s, "Distributor\n");
 	seq_printf(s, "===========\n");
 	seq_printf(s, "vgic_model:\t%s\n", v3 ? "GICv3" : "GICv2");
 	seq_printf(s, "nr_spis:\t%d\n", dist->nr_spis);
 	if (v3)
-		seq_printf(s, "nr_lpis:\t%d\n", iter->nr_lpis);
+		seq_printf(s, "nr_lpis:\t%d\n", vgic_count_lpis(kvm));
 	seq_printf(s, "enabled:\t%d\n", dist->enabled);
 	seq_printf(s, "\n");
 
@@ -283,16 +250,13 @@ static int vgic_debug_show(struct seq_file *s, void *v)
 	if (iter->vcpu_id < iter->nr_cpus)
 		vcpu = kvm_get_vcpu(kvm, iter->vcpu_id);
 
-	/*
-	 * Expect this to succeed, as iter_mark_lpis() takes a reference on
-	 * every LPI to be visited.
-	 */
 	if (iter->intid < VGIC_NR_PRIVATE_IRQS)
 		irq = vgic_get_vcpu_irq(vcpu, iter->intid);
 	else
 		irq = vgic_get_irq(kvm, iter->intid);
-	if (WARN_ON_ONCE(!irq))
-		return -EINVAL;
+
+	if (!irq)
+		return 0;
 
 	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 	print_irq_state(s, irq, vcpu);
@@ -320,3 +284,230 @@ void vgic_debug_init(struct kvm *kvm)
 void vgic_debug_destroy(struct kvm *kvm)
 {
 }
+
+/**
+ * struct vgic_its_iter - Iterator for traversing VGIC ITS device tables.
+ * @dev: Pointer to the current its_device being processed.
+ * @ite: Pointer to the current its_ite within the device being processed.
+ *
+ * This structure is used to maintain the current position during iteration
+ * over the ITS device tables. It holds pointers to both the current device
+ * and the current ITE within that device.
+ */
+struct vgic_its_iter {
+	struct its_device *dev;
+	struct its_ite *ite;
+};
+
+/**
+ * end_of_iter - Checks if the iterator has reached the end.
+ * @iter: The iterator to check.
+ *
+ * When the iterator completed processing the final ITE in the last device
+ * table, it was marked to indicate the end of iteration by setting its
+ * device and ITE pointers to NULL.
+ * This function checks whether the iterator was marked as end.
+ *
+ * Return: True if the iterator is marked as end, false otherwise.
+ */
+static inline bool end_of_iter(struct vgic_its_iter *iter)
+{
+	return !iter->dev && !iter->ite;
+}
+
+/**
+ * vgic_its_iter_next - Advances the iterator to the next entry in the ITS tables.
+ * @its: The VGIC ITS structure.
+ * @iter: The iterator to advance.
+ *
+ * This function moves the iterator to the next ITE within the current device,
+ * or to the first ITE of the next device if the current ITE is the last in
+ * the device. If the current device is the last device, the iterator is set
+ * to indicate the end of iteration.
+ */
+static void vgic_its_iter_next(struct vgic_its *its, struct vgic_its_iter *iter)
+{
+	struct its_device *dev = iter->dev;
+	struct its_ite *ite = iter->ite;
+
+	if (!ite || list_is_last(&ite->ite_list, &dev->itt_head)) {
+		if (list_is_last(&dev->dev_list, &its->device_list)) {
+			dev = NULL;
+			ite = NULL;
+		} else {
+			dev = list_next_entry(dev, dev_list);
+			ite = list_first_entry_or_null(&dev->itt_head,
+						       struct its_ite,
+						       ite_list);
+		}
+	} else {
+		ite = list_next_entry(ite, ite_list);
+	}
+
+	iter->dev = dev;
+	iter->ite = ite;
+}
+
+/**
+ * vgic_its_debug_start - Start function for the seq_file interface.
+ * @s: The seq_file structure.
+ * @pos: The starting position (offset).
+ *
+ * This function initializes the iterator to the beginning of the ITS tables
+ * and advances it to the specified position. It acquires the its_lock mutex
+ * to protect shared data.
+ *
+ * Return: An iterator pointer on success, NULL if no devices are found or
+ *         the end of the list is reached, or ERR_PTR(-ENOMEM) on memory
+ *         allocation failure.
+ */
+static void *vgic_its_debug_start(struct seq_file *s, loff_t *pos)
+{
+	struct vgic_its *its = s->private;
+	struct vgic_its_iter *iter;
+	struct its_device *dev;
+	loff_t offset = *pos;
+
+	mutex_lock(&its->its_lock);
+
+	dev = list_first_entry_or_null(&its->device_list,
+				       struct its_device, dev_list);
+	if (!dev)
+		return NULL;
+
+	iter = kmalloc_obj(*iter);
+	if (!iter)
+		return ERR_PTR(-ENOMEM);
+
+	iter->dev = dev;
+	iter->ite = list_first_entry_or_null(&dev->itt_head,
+					     struct its_ite, ite_list);
+
+	while (!end_of_iter(iter) && offset--)
+		vgic_its_iter_next(its, iter);
+
+	if (end_of_iter(iter)) {
+		kfree(iter);
+		return NULL;
+	}
+
+	return iter;
+}
+
+/**
+ * vgic_its_debug_next - Next function for the seq_file interface.
+ * @s: The seq_file structure.
+ * @v: The current iterator.
+ * @pos: The current position (offset).
+ *
+ * This function advances the iterator to the next entry and increments the
+ * position.
+ *
+ * Return: An iterator pointer on success, or NULL if the end of the list is
+ *         reached.
+ */
+static void *vgic_its_debug_next(struct seq_file *s, void *v, loff_t *pos)
+{
+	struct vgic_its *its = s->private;
+	struct vgic_its_iter *iter = v;
+
+	++*pos;
+	vgic_its_iter_next(its, iter);
+
+	if (end_of_iter(iter)) {
+		kfree(iter);
+		return NULL;
+	}
+	return iter;
+}
+
+/**
+ * vgic_its_debug_stop - Stop function for the seq_file interface.
+ * @s: The seq_file structure.
+ * @v: The current iterator.
+ *
+ * This function frees the iterator and releases the its_lock mutex.
+ */
+static void vgic_its_debug_stop(struct seq_file *s, void *v)
+{
+	struct vgic_its *its = s->private;
+	struct vgic_its_iter *iter = v;
+
+	if (!IS_ERR_OR_NULL(iter))
+		kfree(iter);
+	mutex_unlock(&its->its_lock);
+}
+
+/**
+ * vgic_its_debug_show - Show function for the seq_file interface.
+ * @s: The seq_file structure.
+ * @v: The current iterator.
+ *
+ * This function formats and prints the ITS table entry information to the
+ * seq_file output.
+ *
+ * Return: 0 on success.
+ */
+static int vgic_its_debug_show(struct seq_file *s, void *v)
+{
+	struct vgic_its_iter *iter = v;
+	struct its_device *dev = iter->dev;
+	struct its_ite *ite = iter->ite;
+
+	if (!ite)
+		return 0;
+
+	if (list_is_first(&ite->ite_list, &dev->itt_head)) {
+		seq_printf(s, "\n");
+		seq_printf(s, "Device ID: 0x%x, Event ID Range: [0 - %llu]\n",
+			   dev->device_id, BIT_ULL(dev->num_eventid_bits) - 1);
+		seq_printf(s, "EVENT_ID    INTID  HWINTID   TARGET   COL_ID HW\n");
+		seq_printf(s, "-----------------------------------------------\n");
+	}
+
+	if (ite->irq && ite->collection) {
+		seq_printf(s, "%8u %8u %8u %8u %8u %2d\n",
+			   ite->event_id, ite->irq->intid, ite->irq->hwintid,
+			   ite->collection->target_addr,
+			   ite->collection->collection_id, ite->irq->hw);
+	}
+
+	return 0;
+}
+
+static const struct seq_operations vgic_its_debug_sops = {
+	.start = vgic_its_debug_start,
+	.next  = vgic_its_debug_next,
+	.stop  = vgic_its_debug_stop,
+	.show  = vgic_its_debug_show
+};
+
+DEFINE_SEQ_ATTRIBUTE(vgic_its_debug);
+
+/**
+ * vgic_its_debug_init - Initializes the debugfs interface for VGIC ITS.
+ * @dev: The KVM device structure.
+ *
+ * This function creates a debugfs file named "vgic-its-state@%its_base"
+ * to expose the ITS table information.
+ *
+ * Return: 0 on success.
+ */
+int vgic_its_debug_init(struct kvm_device *dev)
+{
+	struct vgic_its *its = dev->private;
+	char *name;
+
+	name = kasprintf(GFP_KERNEL, "vgic-its-state@%llx", (u64)its->vgic_its_base);
+	if (!name)
+		return -ENOMEM;
+
+	debugfs_create_file(name, 0444, dev->kvm->debugfs_dentry, its, &vgic_its_debug_fops);
+
+	kfree(name);
+	return 0;
+}
+
+void vgic_its_debug_destroy(struct kvm_device *dev)
+{
+}