[patch 14/20] genirq/msi: Provide new domain id based interfaces for freeing interrupts

Thomas Gleixner
2022-11-11T14:03:05Z

Provide two sorts of interfaces to handle the different use cases:

- msi_domain_free_irqs_range():

Handles a caller defined precise range

- msi_domain_free_irqs_all():

Frees all interrupts associated to a domain

The latter is useful for device teardown and to handle the legacy MSI support
which does not have any range information available.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
include/linux/msi.h | 9 +++
kernel/irq/msi.c | 146 +++++++++++++++++++++++++++++++++++++++++++---------
2 files changed, 132 insertions(+), 23 deletions(-)

--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -486,6 +486,15 @@ int msi_domain_alloc_irqs(struct irq_dom
int nvec);
void msi_domain_free_irqs_descs_locked(struct irq_domain *domain, struct device *dev);
void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);
+
+void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid,
+ unsigned int first, unsigned int last);
+void msi_domain_free_irqs_range(struct device *dev, unsigned int domid,
+ unsigned int first, unsigned int last);
+
+void msi_domain_free_irqs_all_locked(struct device *dev, unsigned int domid);
+void msi_domain_free_irqs_all(struct device *dev, unsigned int domid);
+
struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain);

struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -583,7 +583,25 @@ static inline void msi_sysfs_remove_desc
#endif /* !CONFIG_SYSFS */

static int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec);
-static void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev);
+
+static struct irq_domain *msi_get_device_domain(struct device *dev, unsigned int domid)
+{
+ struct irq_domain *domain;
+
+ lockdep_assert_held(&dev->msi.data->mutex);
+
+ if (WARN_ON_ONCE(domid >= MSI_MAX_DEVICE_IRQDOMAINS))
+ return NULL;
+
+ domain = dev->msi.data->__irqdomains[domid];
+ if (!domain)
+ return NULL;
+
+ if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain)))
+ return NULL;
+
+ return domain;
+}

static inline void irq_chip_write_msi_msg(struct irq_data *data,
struct msi_msg *msg)
@@ -744,7 +762,6 @@ static struct msi_domain_ops msi_domain_
.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)
@@ -758,8 +775,6 @@ static void msi_domain_update_dom_ops(st

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;
@@ -1108,15 +1123,23 @@ int msi_domain_alloc_irqs(struct irq_dom
return ret;
}

-static void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
+static void __msi_domain_free_irqs(struct device *dev, struct irq_domain *domain,
+ struct msi_ctrl *ctrl)
{
struct msi_domain_info *info = domain->host_data;
+ struct xarray *xa = &dev->msi.data->__store;
struct irq_data *irqd;
struct msi_desc *desc;
- int i;
+ unsigned long idx;
+ int i, base;
+
+ base = ctrl->domid * MSI_XA_DOMAIN_SIZE;
+
+ xa_for_each_range(xa, idx, desc, ctrl->first + base, ctrl->last + base) {
+ /* Only handle MSI entries which have an interrupt associated */
+ if (!msi_desc_match(desc, MSI_DESC_ASSOCIATED))
+ continue;

- /* 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);
@@ -1131,11 +1154,99 @@ static void __msi_domain_free_irqs(struc
}
}

-static void msi_domain_free_msi_descs(struct msi_domain_info *info,
- struct device *dev)
+static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl)
{
+ struct msi_domain_info *info;
+ struct msi_domain_ops *ops;
+ struct irq_domain *domain;
+
+ if (!msi_ctrl_valid(dev, ctrl))
+ return;
+
+ domain = msi_get_device_domain(dev, ctrl->domid);
+ if (!domain)
+ return;
+
+ info = domain->host_data;
+ ops = info->ops;
+
+ if (ops->domain_free_irqs)
+ ops->domain_free_irqs(domain, dev);
+ else
+ __msi_domain_free_irqs(dev, domain, ctrl);
+
+ if (ops->msi_post_free)
+ ops->msi_post_free(domain, dev);
+
if (info->flags & MSI_FLAG_FREE_MSI_DESCS)
- msi_free_msi_descs(dev);
+ msi_domain_free_descs(dev, ctrl);
+}
+
+/**
+ * msi_domain_free_irqs_range_locked - Free a range of interrupts from a MSI interrupt domain
+ * associated to @dev with msi_lock held
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are freed
+ * @domid: Id of the interrupt domain to operate on
+ * @first: First index to free (inclusive)
+ * @last: Last index to free (inclusive)
+ */
+void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid,
+ unsigned int first, unsigned int last)
+{
+ struct msi_ctrl ctrl = {
+ .domid = domid,
+ .first = first,
+ .last = last,
+ };
+ msi_domain_free_locked(dev, &ctrl);
+}
+
+/**
+ * msi_domain_free_irqs_range - Free a range of interrupts from a MSI interrupt domain
+ * associated to @dev
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are freed
+ * @domid: Id of the interrupt domain to operate on
+ * @first: First index to free (inclusive)
+ * @last: Last index to free (inclusive)
+ */
+void msi_domain_free_irqs_range(struct device *dev, unsigned int domid,
+ unsigned int first, unsigned int last)
+{
+ msi_lock_descs(dev);
+ msi_domain_free_irqs_range_locked(dev, domid, first, last);
+ msi_unlock_descs(dev);
+}
+
+/**
+ * msi_domain_free_irqs_all_locked - Free all interrupts from a MSI interrupt
+ * associated to a device
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are freed
+ * @domid: The id of the domain to operate on
+ *
+ * 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_all_locked(struct device *dev, unsigned int domid)
+{
+ msi_domain_free_irqs_range_locked(dev, domid, 0, MSI_MAX_INDEX);
+}
+
+/**
+ * msi_domain_free_irqs_all - Free all interrupts from a MSI interrupt
+ * associated to a device
+ * @dev: Pointer to device struct of the device for which the interrupts
+ * are freed
+ * @domid: The id of the domain to operate on
+ */
+void msi_domain_free_irqs_all(struct device *dev, unsigned int domid)
+{
+ msi_lock_descs(dev);
+ msi_domain_free_irqs_range_locked(dev, domid, 0, MSI_MAX_INDEX);
+ msi_unlock_descs(dev);
}

/**
@@ -1150,18 +1261,7 @@ static void msi_domain_free_msi_descs(st
*/
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;
-
- lockdep_assert_held(&dev->msi.data->mutex);
-
- if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain)))
- return;
-
- ops->domain_free_irqs(domain, dev);
- if (ops->msi_post_free)
- ops->msi_post_free(domain, dev);
- msi_domain_free_msi_descs(info, dev);
+ msi_domain_free_irqs_range_locked(dev, MSI_DEFAULT_DOMAIN, 0, MSI_MAX_INDEX);
}

/**