1 files changed, 667 insertions, 143 deletions

diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index eb95f6106a1e..a9ee535293eb 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -5,7 +5,7 @@
  *
  * This file is licensed under GPLv2.
  *
- * This file contains common code to support Message Signalled Interrupt for
+ * This file contains common code to support Message Signaled Interrupts for
  * PCI compatible and non PCI compatible devices.
  */
 #include <linux/types.h>
@@ -14,46 +14,152 @@
 #include <linux/irqdomain.h>
 #include <linux/msi.h>
 #include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/pci.h>
 
 #include "internals.h"
 
+static inline int msi_sysfs_create_group(struct device *dev);
+
 /**
- * alloc_msi_entry - Allocate an initialize msi_entry
+ * msi_alloc_desc - Allocate an initialized msi_desc
  * @dev:	Pointer to the device for which this is allocated
  * @nvec:	The number of vectors used in this entry
  * @affinity:	Optional pointer to an affinity mask array size of @nvec
  *
- * If @affinity is not NULL then an affinity array[@nvec] is allocated
+ * If @affinity is not %NULL then an affinity array[@nvec] is allocated
  * and the affinity masks and flags from @affinity are copied.
+ *
+ * Return: pointer to allocated &msi_desc on success or %NULL on failure
  */
-struct msi_desc *alloc_msi_entry(struct device *dev, int nvec,
-				 const struct irq_affinity_desc *affinity)
+static struct msi_desc *msi_alloc_desc(struct device *dev, int nvec,
+					const struct irq_affinity_desc *affinity)
 {
-	struct msi_desc *desc;
+	struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 
-	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
 	if (!desc)
 		return NULL;
 
-	INIT_LIST_HEAD(&desc->list);
 	desc->dev = dev;
 	desc->nvec_used = nvec;
 	if (affinity) {
-		desc->affinity = kmemdup(affinity,
-			nvec * sizeof(*desc->affinity), GFP_KERNEL);
+		desc->affinity = kmemdup(affinity, nvec * sizeof(*desc->affinity), GFP_KERNEL);
 		if (!desc->affinity) {
 			kfree(desc);
 			return NULL;
 		}
 	}
-
 	return desc;
 }
 
-void free_msi_entry(struct msi_desc *entry)
+static void msi_free_desc(struct msi_desc *desc)
+{
+	kfree(desc->affinity);
+	kfree(desc);
+}
+
+static int msi_insert_desc(struct msi_device_data *md, struct msi_desc *desc, unsigned int index)
+{
+	int ret;
+
+	desc->msi_index = index;
+	ret = xa_insert(&md->__store, index, desc, GFP_KERNEL);
+	if (ret)
+		msi_free_desc(desc);
+	return ret;
+}
+
+/**
+ * msi_add_msi_desc - Allocate and initialize a MSI descriptor
+ * @dev:	Pointer to the device for which the descriptor is allocated
+ * @init_desc:	Pointer to an MSI descriptor to initialize the new descriptor
+ *
+ * Return: 0 on success or an appropriate failure code.
+ */
+int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc)
+{
+	struct msi_desc *desc;
+
+	lockdep_assert_held(&dev->msi.data->mutex);
+
+	desc = msi_alloc_desc(dev, init_desc->nvec_used, init_desc->affinity);
+	if (!desc)
+		return -ENOMEM;
+
+	/* Copy type specific data to the new descriptor. */
+	desc->pci = init_desc->pci;
+	return msi_insert_desc(dev->msi.data, desc, init_desc->msi_index);
+}
+
+/**
+ * msi_add_simple_msi_descs - Allocate and initialize MSI descriptors
+ * @dev:	Pointer to the device for which the descriptors are allocated
+ * @index:	Index for the first MSI descriptor
+ * @ndesc:	Number of descriptors to allocate
+ *
+ * Return: 0 on success or an appropriate failure code.
+ */
+static int msi_add_simple_msi_descs(struct device *dev, unsigned int index, unsigned int ndesc)
 {
-	kfree(entry->affinity);
-	kfree(entry);
+	unsigned int idx, last = index + ndesc - 1;
+	struct msi_desc *desc;
+	int ret;
+
+	lockdep_assert_held(&dev->msi.data->mutex);
+
+	for (idx = index; idx <= last; idx++) {
+		desc = msi_alloc_desc(dev, 1, NULL);
+		if (!desc)
+			goto fail_mem;
+		ret = msi_insert_desc(dev->msi.data, desc, idx);
+		if (ret)
+			goto fail;
+	}
+	return 0;
+
+fail_mem:
+	ret = -ENOMEM;
+fail:
+	msi_free_msi_descs_range(dev, MSI_DESC_NOTASSOCIATED, index, last);
+	return ret;
+}
+
+static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter)
+{
+	switch (filter) {
+	case MSI_DESC_ALL:
+		return true;
+	case MSI_DESC_NOTASSOCIATED:
+		return !desc->irq;
+	case MSI_DESC_ASSOCIATED:
+		return !!desc->irq;
+	}
+	WARN_ON_ONCE(1);
+	return false;
+}
+
+/**
+ * msi_free_msi_descs_range - Free MSI descriptors of a device
+ * @dev:		Device to free the descriptors
+ * @filter:		Descriptor state filter
+ * @first_index:	Index to start freeing from
+ * @last_index:		Last index to be freed
+ */
+void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter,
+			      unsigned int first_index, unsigned int last_index)
+{
+	struct xarray *xa = &dev->msi.data->__store;
+	struct msi_desc *desc;
+	unsigned long idx;
+
+	lockdep_assert_held(&dev->msi.data->mutex);
+
+	xa_for_each_range(xa, idx, desc, first_index, last_index) {
+		if (msi_desc_match(desc, filter)) {
+			xa_erase(xa, idx);
+			msi_free_desc(desc);
+		}
+	}
 }
 
 void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
@@ -69,6 +175,290 @@ void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
 }
 EXPORT_SYMBOL_GPL(get_cached_msi_msg);
 
+static void msi_device_data_release(struct device *dev, void *res)
+{
+	struct msi_device_data *md = res;
+
+	WARN_ON_ONCE(!xa_empty(&md->__store));
+	xa_destroy(&md->__store);
+	dev->msi.data = NULL;
+}
+
+/**
+ * msi_setup_device_data - Setup MSI device data
+ * @dev:	Device for which MSI device data should be set up
+ *
+ * Return: 0 on success, appropriate error code otherwise
+ *
+ * This can be called more than once for @dev. If the MSI device data is
+ * already allocated the call succeeds. The allocated memory is
+ * automatically released when the device is destroyed.
+ */
+int msi_setup_device_data(struct device *dev)
+{
+	struct msi_device_data *md;
+	int ret;
+
+	if (dev->msi.data)
+		return 0;
+
+	md = devres_alloc(msi_device_data_release, sizeof(*md), GFP_KERNEL);
+	if (!md)
+		return -ENOMEM;
+
+	ret = msi_sysfs_create_group(dev);
+	if (ret) {
+		devres_free(md);
+		return ret;
+	}
+
+	xa_init(&md->__store);
+	mutex_init(&md->mutex);
+	dev->msi.data = md;
+	devres_add(dev, md);
+	return 0;
+}
+
+/**
+ * msi_lock_descs - Lock the MSI descriptor storage of a device
+ * @dev:	Device to operate on
+ */
+void msi_lock_descs(struct device *dev)
+{
+	mutex_lock(&dev->msi.data->mutex);
+}
+EXPORT_SYMBOL_GPL(msi_lock_descs);
+
+/**
+ * msi_unlock_descs - Unlock the MSI descriptor storage of a device
+ * @dev:	Device to operate on
+ */
+void msi_unlock_descs(struct device *dev)
+{
+	/* Invalidate the index wich was cached by the iterator */
+	dev->msi.data->__iter_idx = MSI_MAX_INDEX;
+	mutex_unlock(&dev->msi.data->mutex);
+}
+EXPORT_SYMBOL_GPL(msi_unlock_descs);
+
+static struct msi_desc *msi_find_desc(struct msi_device_data *md, enum msi_desc_filter filter)
+{
+	struct msi_desc *desc;
+
+	xa_for_each_start(&md->__store, md->__iter_idx, desc, md->__iter_idx) {
+		if (msi_desc_match(desc, filter))
+			return desc;
+	}
+	md->__iter_idx = MSI_MAX_INDEX;
+	return NULL;
+}
+
+/**
+ * msi_first_desc - Get the first MSI descriptor of a device
+ * @dev:	Device to operate on
+ * @filter:	Descriptor state filter
+ *
+ * Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs()
+ * must be invoked before the call.
+ *
+ * Return: Pointer to the first MSI descriptor matching the search
+ *	   criteria, NULL if none found.
+ */
+struct msi_desc *msi_first_desc(struct device *dev, enum msi_desc_filter filter)
+{
+	struct msi_device_data *md = dev->msi.data;
+
+	if (WARN_ON_ONCE(!md))
+		return NULL;
+
+	lockdep_assert_held(&md->mutex);
+
+	md->__iter_idx = 0;
+	return msi_find_desc(md, filter);
+}
+EXPORT_SYMBOL_GPL(msi_first_desc);
+
+/**
+ * msi_next_desc - Get the next MSI descriptor of a device
+ * @dev:	Device to operate on
+ *
+ * The first invocation of msi_next_desc() has to be preceeded by a
+ * successful invocation of __msi_first_desc(). Consecutive invocations are
+ * only valid if the previous one was successful. All these operations have
+ * to be done within the same MSI mutex held region.
+ *
+ * Return: Pointer to the next MSI descriptor matching the search
+ *	   criteria, NULL if none found.
+ */
+struct msi_desc *msi_next_desc(struct device *dev, enum msi_desc_filter filter)
+{
+	struct msi_device_data *md = dev->msi.data;
+
+	if (WARN_ON_ONCE(!md))
+		return NULL;
+
+	lockdep_assert_held(&md->mutex);
+
+	if (md->__iter_idx >= (unsigned long)MSI_MAX_INDEX)
+		return NULL;
+
+	md->__iter_idx++;
+	return msi_find_desc(md, filter);
+}
+EXPORT_SYMBOL_GPL(msi_next_desc);
+
+/**
+ * msi_get_virq - Return Linux interrupt number of a MSI interrupt
+ * @dev:	Device to operate on
+ * @index:	MSI interrupt index to look for (0-based)
+ *
+ * Return: The Linux interrupt number on success (> 0), 0 if not found
+ */
+unsigned int msi_get_virq(struct device *dev, unsigned int index)
+{
+	struct msi_desc *desc;
+	unsigned int ret = 0;
+	bool pcimsi;
+
+	if (!dev->msi.data)
+		return 0;
+
+	pcimsi = dev_is_pci(dev) ? to_pci_dev(dev)->msi_enabled : false;
+
+	msi_lock_descs(dev);
+	desc = xa_load(&dev->msi.data->__store, pcimsi ? 0 : index);
+	if (desc && desc->irq) {
+		/*
+		 * PCI-MSI has only one descriptor for multiple interrupts.
+		 * PCI-MSIX and platform MSI use a descriptor per
+		 * interrupt.
+		 */
+		if (pcimsi) {
+			if (index < desc->nvec_used)
+				ret = desc->irq + index;
+		} else {
+			ret = desc->irq;
+		}
+	}
+	msi_unlock_descs(dev);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(msi_get_virq);
+
+#ifdef CONFIG_SYSFS
+static struct attribute *msi_dev_attrs[] = {
+	NULL
+};
+
+static const struct attribute_group msi_irqs_group = {
+	.name	= "msi_irqs",
+	.attrs	= msi_dev_attrs,
+};
+
+static inline int msi_sysfs_create_group(struct device *dev)
+{
+	return devm_device_add_group(dev, &msi_irqs_group);
+}
+
+static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	/* MSI vs. MSIX is per device not per interrupt */
+	bool is_msix = dev_is_pci(dev) ? to_pci_dev(dev)->msix_enabled : false;
+
+	return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi");
+}
+
+static void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc)
+{
+	struct device_attribute *attrs = desc->sysfs_attrs;
+	int i;
+
+	if (!attrs)
+		return;
+
+	desc->sysfs_attrs = NULL;
+	for (i = 0; i < desc->nvec_used; i++) {
+		if (attrs[i].show)
+			sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
+		kfree(attrs[i].attr.name);
+	}
+	kfree(attrs);
+}
+
+static int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc)
+{
+	struct device_attribute *attrs;
+	int ret, i;
+
+	attrs = kcalloc(desc->nvec_used, sizeof(*attrs), GFP_KERNEL);
+	if (!attrs)
+		return -ENOMEM;
+
+	desc->sysfs_attrs = attrs;
+	for (i = 0; i < desc->nvec_used; i++) {
+		sysfs_attr_init(&attrs[i].attr);
+		attrs[i].attr.name = kasprintf(GFP_KERNEL, "%d", desc->irq + i);
+		if (!attrs[i].attr.name) {
+			ret = -ENOMEM;
+			goto fail;
+		}
+
+		attrs[i].attr.mode = 0444;
+		attrs[i].show = msi_mode_show;
+
+		ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
+		if (ret) {
+			attrs[i].show = NULL;
+			goto fail;
+		}
+	}
+	return 0;
+
+fail:
+	msi_sysfs_remove_desc(dev, desc);
+	return ret;
+}
+
+#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
+/**
+ * msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device
+ * @dev:	The device (PCI, platform etc) which will get sysfs entries
+ */
+int msi_device_populate_sysfs(struct device *dev)
+{
+	struct msi_desc *desc;
+	int ret;
+
+	msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
+		if (desc->sysfs_attrs)
+			continue;
+		ret = msi_sysfs_populate_desc(dev, desc);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+/**
+ * msi_device_destroy_sysfs - Destroy msi_irqs sysfs entries for a device
+ * @dev:		The device (PCI, platform etc) for which to remove
+ *			sysfs entries
+ */
+void msi_device_destroy_sysfs(struct device *dev)
+{
+	struct msi_desc *desc;
+
+	msi_for_each_desc(desc, dev, MSI_DESC_ALL)
+		msi_sysfs_remove_desc(dev, desc);
+}
+#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK */
+#else /* CONFIG_SYSFS */
+static inline int msi_sysfs_create_group(struct device *dev) { return 0; }
+static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; }
+static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { }
+#endif /* !CONFIG_SYSFS */
+
 #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
 static inline void irq_chip_write_msi_msg(struct irq_data *data,
 					  struct msi_msg *msg)
@@ -97,6 +487,8 @@ static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg)
  *
  * Intended to be used by MSI interrupt controllers which are
  * implemented with hierarchical domains.
+ *
+ * Return: IRQ_SET_MASK_* result code
  */
 int msi_domain_set_affinity(struct irq_data *irq_data,
 			    const struct cpumask *mask, bool force)
@@ -187,7 +579,6 @@ static const struct irq_domain_ops msi_domain_ops = {
 	.deactivate	= msi_domain_deactivate,
 };
 
-#ifdef GENERIC_MSI_DOMAIN_OPS
 static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info,
 						msi_alloc_info_t *arg)
 {
@@ -206,11 +597,6 @@ static void msi_domain_ops_set_desc(msi_alloc_info_t *arg,
 {
 	arg->desc = desc;
 }
-#else
-#define msi_domain_ops_get_hwirq	NULL
-#define msi_domain_ops_prepare		NULL
-#define msi_domain_ops_set_desc		NULL
-#endif /* !GENERIC_MSI_DOMAIN_OPS */
 
 static int msi_domain_ops_init(struct irq_domain *domain,
 			       struct msi_domain_info *info,
@@ -235,11 +621,13 @@ static int msi_domain_ops_check(struct irq_domain *domain,
 }
 
 static struct msi_domain_ops msi_domain_ops_default = {
-	.get_hwirq	= msi_domain_ops_get_hwirq,
-	.msi_init	= msi_domain_ops_init,
-	.msi_check	= msi_domain_ops_check,
-	.msi_prepare	= msi_domain_ops_prepare,
-	.set_desc	= msi_domain_ops_set_desc,
+	.get_hwirq		= msi_domain_ops_get_hwirq,
+	.msi_init		= msi_domain_ops_init,
+	.msi_check		= msi_domain_ops_check,
+	.msi_prepare		= msi_domain_ops_prepare,
+	.set_desc		= msi_domain_ops_set_desc,
+	.domain_alloc_irqs	= __msi_domain_alloc_irqs,
+	.domain_free_irqs	= __msi_domain_free_irqs,
 };
 
 static void msi_domain_update_dom_ops(struct msi_domain_info *info)
@@ -251,6 +639,14 @@ static void msi_domain_update_dom_ops(struct msi_domain_info *info)
 		return;
 	}
 
+	if (ops->domain_alloc_irqs == NULL)
+		ops->domain_alloc_irqs = msi_domain_ops_default.domain_alloc_irqs;
+	if (ops->domain_free_irqs == NULL)
+		ops->domain_free_irqs = msi_domain_ops_default.domain_free_irqs;
+
+	if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS))
+		return;
+
 	if (ops->get_hwirq == NULL)
 		ops->get_hwirq = msi_domain_ops_default.get_hwirq;
 	if (ops->msi_init == NULL)
@@ -273,10 +669,12 @@ static void msi_domain_update_chip_ops(struct msi_domain_info *info)
 }
 
 /**
- * msi_create_irq_domain - Create a MSI interrupt domain
+ * msi_create_irq_domain - Create an MSI interrupt domain
  * @fwnode:	Optional fwnode of the interrupt controller
  * @info:	MSI domain info
  * @parent:	Parent irq domain
+ *
+ * Return: pointer to the created &struct irq_domain or %NULL on failure
  */
 struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
 					 struct msi_domain_info *info,
@@ -284,8 +682,7 @@ struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
 {
 	struct irq_domain *domain;
 
-	if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
-		msi_domain_update_dom_ops(info);
+	msi_domain_update_dom_ops(info);
 	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
 		msi_domain_update_chip_ops(info);
 
@@ -313,43 +710,38 @@ int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
 }
 
 int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
-			     int virq, int nvec, msi_alloc_info_t *arg)
+			     int virq_base, int nvec, msi_alloc_info_t *arg)
 {
 	struct msi_domain_info *info = domain->host_data;
 	struct msi_domain_ops *ops = info->ops;
 	struct msi_desc *desc;
-	int ret = 0;
+	int ret, virq;
 
-	for_each_msi_entry(desc, dev) {
-		/* Don't even try the multi-MSI brain damage. */
-		if (WARN_ON(!desc->irq || desc->nvec_used != 1)) {
-			ret = -EINVAL;
-			break;
-		}
+	msi_lock_descs(dev);
+	ret = msi_add_simple_msi_descs(dev, virq_base, nvec);
+	if (ret)
+		goto unlock;
 
-		if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
-			continue;
+	for (virq = virq_base; virq < virq_base + nvec; virq++) {
+		desc = xa_load(&dev->msi.data->__store, virq);
+		desc->irq = virq;
 
 		ops->set_desc(arg, desc);
-		/* Assumes the domain mutex is held! */
-		ret = irq_domain_alloc_irqs_hierarchy(domain, desc->irq, 1,
-						      arg);
+		ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
 		if (ret)
-			break;
-
-		irq_set_msi_desc_off(desc->irq, 0, desc);
-	}
-
-	if (ret) {
-		/* Mop up the damage */
-		for_each_msi_entry(desc, dev) {
-			if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
-				continue;
+			goto fail;
 
-			irq_domain_free_irqs_common(domain, desc->irq, 1);
-		}
+		irq_set_msi_desc(virq, desc);
 	}
+	msi_unlock_descs(dev);
+	return 0;
 
+fail:
+	for (--virq; virq >= virq_base; virq--)
+		irq_domain_free_irqs_common(domain, virq, 1);
+	msi_free_msi_descs_range(dev, MSI_DESC_ALL, virq_base, virq_base + nvec - 1);
+unlock:
+	msi_unlock_descs(dev);
 	return ret;
 }
 
@@ -370,8 +762,13 @@ static bool msi_check_reservation_mode(struct irq_domain *domain,
 {
 	struct msi_desc *desc;
 
-	if (domain->bus_token != DOMAIN_BUS_PCI_MSI)
+	switch(domain->bus_token) {
+	case DOMAIN_BUS_PCI_MSI:
+	case DOMAIN_BUS_VMD_MSI:
+		break;
+	default:
 		return false;
+	}
 
 	if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
 		return false;
@@ -381,144 +778,271 @@ static bool msi_check_reservation_mode(struct irq_domain *domain,
 
 	/*
 	 * Checking the first MSI descriptor is sufficient. MSIX supports
-	 * masking and MSI does so when the maskbit is set.
+	 * masking and MSI does so when the can_mask attribute is set.
 	 */
-	desc = first_msi_entry(dev);
-	return desc->msi_attrib.is_msix || desc->msi_attrib.maskbit;
+	desc = msi_first_desc(dev, MSI_DESC_ALL);
+	return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask;
 }
 
-/**
- * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
- * @domain:	The domain to allocate from
- * @dev:	Pointer to device struct of the device for which the interrupts
- *		are allocated
- * @nvec:	The number of interrupts to allocate
- *
- * Returns 0 on success or an error code.
- */
-int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
-			  int nvec)
+static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc,
+			       int allocated)
+{
+	switch(domain->bus_token) {
+	case DOMAIN_BUS_PCI_MSI:
+	case DOMAIN_BUS_VMD_MSI:
+		if (IS_ENABLED(CONFIG_PCI_MSI))
+			break;
+		fallthrough;
+	default:
+		return -ENOSPC;
+	}
+
+	/* Let a failed PCI multi MSI allocation retry */
+	if (desc->nvec_used > 1)
+		return 1;
+
+	/* If there was a successful allocation let the caller know */
+	return allocated ? allocated : -ENOSPC;
+}
+
+#define VIRQ_CAN_RESERVE	0x01
+#define VIRQ_ACTIVATE		0x02
+#define VIRQ_NOMASK_QUIRK	0x04
+
+static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags)
+{
+	struct irq_data *irqd = irq_domain_get_irq_data(domain, virq);
+	int ret;
+
+	if (!(vflags & VIRQ_CAN_RESERVE)) {
+		irqd_clr_can_reserve(irqd);
+		if (vflags & VIRQ_NOMASK_QUIRK)
+			irqd_set_msi_nomask_quirk(irqd);
+
+		/*
+		 * If the interrupt is managed but no CPU is available to
+		 * service it, shut it down until better times. Note that
+		 * we only do this on the !RESERVE path as x86 (the only
+		 * architecture using this flag) deals with this in a
+		 * different way by using a catch-all vector.
+		 */
+		if ((vflags & VIRQ_ACTIVATE) &&
+		    irqd_affinity_is_managed(irqd) &&
+		    !cpumask_intersects(irq_data_get_affinity_mask(irqd),
+					cpu_online_mask)) {
+			    irqd_set_managed_shutdown(irqd);
+			    return 0;
+		    }
+	}
+
+	if (!(vflags & VIRQ_ACTIVATE))
+		return 0;
+
+	ret = irq_domain_activate_irq(irqd, vflags & VIRQ_CAN_RESERVE);
+	if (ret)
+		return ret;
+	/*
+	 * If the interrupt uses reservation mode, clear the activated bit
+	 * so request_irq() will assign the final vector.
+	 */
+	if (vflags & VIRQ_CAN_RESERVE)
+		irqd_clr_activated(irqd);
+	return 0;
+}
+
+int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
+			    int nvec)
 {
 	struct msi_domain_info *info = domain->host_data;
 	struct msi_domain_ops *ops = info->ops;
-	struct irq_data *irq_data;
+	msi_alloc_info_t arg = { };
+	unsigned int vflags = 0;
 	struct msi_desc *desc;
-	msi_alloc_info_t arg;
+	int allocated = 0;
 	int i, ret, virq;
-	bool can_reserve;
 
 	ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg);
 	if (ret)
 		return ret;
 
-	for_each_msi_entry(desc, dev) {
+	/*
+	 * This flag is set by the PCI layer as we need to activate
+	 * the MSI entries before the PCI layer enables MSI in the
+	 * card. Otherwise the card latches a random msi message.
+	 */
+	if (info->flags & MSI_FLAG_ACTIVATE_EARLY)
+		vflags |= VIRQ_ACTIVATE;
+
+	/*
+	 * Interrupt can use a reserved vector and will not occupy
+	 * a real device vector until the interrupt is requested.
+	 */
+	if (msi_check_reservation_mode(domain, info, dev)) {
+		vflags |= VIRQ_CAN_RESERVE;
+		/*
+		 * MSI affinity setting requires a special quirk (X86) when
+		 * reservation mode is active.
+		 */
+		if (domain->flags & IRQ_DOMAIN_MSI_NOMASK_QUIRK)
+			vflags |= VIRQ_NOMASK_QUIRK;
+	}
+
+	msi_for_each_desc(desc, dev, MSI_DESC_NOTASSOCIATED) {
 		ops->set_desc(&arg, desc);
 
 		virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used,
 					       dev_to_node(dev), &arg, false,
 					       desc->affinity);
-		if (virq < 0) {
-			ret = -ENOSPC;
-			if (ops->handle_error)
-				ret = ops->handle_error(domain, desc, ret);
-			if (ops->msi_finish)
-				ops->msi_finish(&arg, ret);
-			return ret;
-		}
+		if (virq < 0)
+			return msi_handle_pci_fail(domain, desc, allocated);
 
 		for (i = 0; i < desc->nvec_used; i++) {
 			irq_set_msi_desc_off(virq, i, desc);
 			irq_debugfs_copy_devname(virq + i, dev);
+			ret = msi_init_virq(domain, virq + i, vflags);
+			if (ret)
+				return ret;
+		}
+		if (info->flags & MSI_FLAG_DEV_SYSFS) {
+			ret = msi_sysfs_populate_desc(dev, desc);
+			if (ret)
+				return ret;
 		}
+		allocated++;
 	}
+	return 0;
+}
 
-	if (ops->msi_finish)
-		ops->msi_finish(&arg, 0);
+static int msi_domain_add_simple_msi_descs(struct msi_domain_info *info,
+					   struct device *dev,
+					   unsigned int num_descs)
+{
+	if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS))
+		return 0;
 
-	can_reserve = msi_check_reservation_mode(domain, info, dev);
+	return msi_add_simple_msi_descs(dev, 0, num_descs);
+}
 
-	for_each_msi_entry(desc, dev) {
-		virq = desc->irq;
-		if (desc->nvec_used == 1)
-			dev_dbg(dev, "irq %d for MSI\n", virq);
-		else
-			dev_dbg(dev, "irq [%d-%d] for MSI\n",
-				virq, virq + desc->nvec_used - 1);
-		/*
-		 * This flag is set by the PCI layer as we need to activate
-		 * the MSI entries before the PCI layer enables MSI in the
-		 * card. Otherwise the card latches a random msi message.
-		 */
-		if (!(info->flags & MSI_FLAG_ACTIVATE_EARLY))
-			continue;
+/**
+ * msi_domain_alloc_irqs_descs_locked - Allocate interrupts from a MSI interrupt domain
+ * @domain:	The domain to allocate from
+ * @dev:	Pointer to device struct of the device for which the interrupts
+ *		are allocated
+ * @nvec:	The number of interrupts to allocate
+ *
+ * Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
+ * pair. Use this for MSI irqdomains which implement their own vector
+ * allocation/free.
+ *
+ * Return: %0 on success or an error code.
+ */
+int msi_domain_alloc_irqs_descs_locked(struct irq_domain *domain, struct device *dev,
+				       int nvec)
+{
+	struct msi_domain_info *info = domain->host_data;
+	struct msi_domain_ops *ops = info->ops;
+	int ret;
 
-		irq_data = irq_domain_get_irq_data(domain, desc->irq);
-		if (!can_reserve) {
-			irqd_clr_can_reserve(irq_data);
-			if (domain->flags & IRQ_DOMAIN_MSI_NOMASK_QUIRK)
-				irqd_set_msi_nomask_quirk(irq_data);
-		}
-		ret = irq_domain_activate_irq(irq_data, can_reserve);
-		if (ret)
-			goto cleanup;
-	}
+	lockdep_assert_held(&dev->msi.data->mutex);
 
-	/*
-	 * If these interrupts use reservation mode, clear the activated bit
-	 * so request_irq() will assign the final vector.
-	 */
-	if (can_reserve) {
-		for_each_msi_entry(desc, dev) {
-			irq_data = irq_domain_get_irq_data(domain, desc->irq);
-			irqd_clr_activated(irq_data);
+	ret = msi_domain_add_simple_msi_descs(info, dev, nvec);
+	if (ret)
+		return ret;
+
+	ret = ops->domain_alloc_irqs(domain, dev, nvec);
+	if (ret)
+		msi_domain_free_irqs_descs_locked(domain, dev);
+	return ret;
+}
+
+/**
+ * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
+ * @domain:	The domain to allocate from
+ * @dev:	Pointer to device struct of the device for which the interrupts
+ *		are allocated
+ * @nvec:	The number of interrupts to allocate
+ *
+ * Return: %0 on success or an error code.
+ */
+int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec)
+{
+	int ret;
+
+	msi_lock_descs(dev);
+	ret = msi_domain_alloc_irqs_descs_locked(domain, dev, nvec);
+	msi_unlock_descs(dev);
+	return ret;
+}
+
+void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
+{
+	struct msi_domain_info *info = domain->host_data;
+	struct irq_data *irqd;
+	struct msi_desc *desc;
+	int i;
+
+	/* Only handle MSI entries which have an interrupt associated */
+	msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
+		/* Make sure all interrupts are deactivated */
+		for (i = 0; i < desc->nvec_used; i++) {
+			irqd = irq_domain_get_irq_data(domain, desc->irq + i);
+			if (irqd && irqd_is_activated(irqd))
+				irq_domain_deactivate_irq(irqd);
 		}
+
+		irq_domain_free_irqs(desc->irq, desc->nvec_used);
+		if (info->flags & MSI_FLAG_DEV_SYSFS)
+			msi_sysfs_remove_desc(dev, desc);
+		desc->irq = 0;
 	}
-	return 0;
+}
 
-cleanup:
-	for_each_msi_entry(desc, dev) {
-		struct irq_data *irqd;
+static void msi_domain_free_msi_descs(struct msi_domain_info *info,
+				      struct device *dev)
+{
+	if (info->flags & MSI_FLAG_FREE_MSI_DESCS)
+		msi_free_msi_descs(dev);
+}
 
-		if (desc->irq == virq)
-			break;
+/**
+ * msi_domain_free_irqs_descs_locked - Free interrupts from a MSI interrupt @domain associated to @dev
+ * @domain:	The domain to managing the interrupts
+ * @dev:	Pointer to device struct of the device for which the interrupts
+ *		are free
+ *
+ * Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
+ * pair. Use this for MSI irqdomains which implement their own vector
+ * allocation.
+ */
+void msi_domain_free_irqs_descs_locked(struct irq_domain *domain, struct device *dev)
+{
+	struct msi_domain_info *info = domain->host_data;
+	struct msi_domain_ops *ops = info->ops;
 
-		irqd = irq_domain_get_irq_data(domain, desc->irq);
-		if (irqd_is_activated(irqd))
-			irq_domain_deactivate_irq(irqd);
-	}
-	msi_domain_free_irqs(domain, dev);
-	return ret;
+	lockdep_assert_held(&dev->msi.data->mutex);
+
+	ops->domain_free_irqs(domain, dev);
+	msi_domain_free_msi_descs(info, dev);
 }
 
 /**
- * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev
+ * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated to @dev
  * @domain:	The domain to managing the interrupts
  * @dev:	Pointer to device struct of the device for which the interrupts
  *		are free
  */
 void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
 {
-	struct msi_desc *desc;
-
-	for_each_msi_entry(desc, dev) {
-		/*
-		 * We might have failed to allocate an MSI early
-		 * enough that there is no IRQ associated to this
-		 * entry. If that's the case, don't do anything.
-		 */
-		if (desc->irq) {
-			irq_domain_free_irqs(desc->irq, desc->nvec_used);
-			desc->irq = 0;
-		}
-	}
+	msi_lock_descs(dev);
+	msi_domain_free_irqs_descs_locked(domain, dev);
+	msi_unlock_descs(dev);
 }
 
 /**
  * msi_get_domain_info - Get the MSI interrupt domain info for @domain
  * @domain:	The interrupt domain to retrieve data from
  *
- * Returns the pointer to the msi_domain_info stored in
- * @domain->host_data.
+ * Return: the pointer to the msi_domain_info stored in @domain->host_data.
  */
 struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
 {