[patch V3 14/22] genirq/msi: Make descriptor freeing domain aware

From: Thomas Gleixner
Date: Thu Nov 24 2022 - 18:25:34 EST


Change the descriptor free functions to take a domain id to prepare for the
upcoming multi MSI domain per device support.

To avoid changing and extending the interfaces over and over use an core
internal control struct and hand the pointer through the various functions.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
V3: Adopt to the domain/xarray storage change
---
include/linux/msi.h | 19 +++++++++++++++--
kernel/irq/msi.c | 58 +++++++++++++++++++++++++++++++++++++++++++---------
2 files changed, 65 insertions(+), 12 deletions(-)

--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -301,10 +301,25 @@ static inline int msi_insert_msi_desc(st
return msi_domain_insert_msi_desc(dev, MSI_DEFAULT_DOMAIN, init_desc);
}

-void msi_free_msi_descs_range(struct device *dev, unsigned int first_index, unsigned int last_index);
+void msi_domain_free_msi_descs_range(struct device *dev, unsigned int domid,
+ unsigned int first, unsigned int last);

/**
- * msi_free_msi_descs - Free MSI descriptors of a device
+ * msi_free_msi_descs_range - Free a range of MSI descriptors of a device
+ * in the default irqdomain
+ *
+ * @dev: Device for which to free the descriptors
+ * @first: Index to start freeing from (inclusive)
+ * @last: Last index to be freed (inclusive)
+ */
+static inline void msi_free_msi_descs_range(struct device *dev, unsigned int first,
+ unsigned int last)
+{
+ msi_domain_free_msi_descs_range(dev, MSI_DEFAULT_DOMAIN, first, last);
+}
+
+/**
+ * msi_free_msi_descs - Free all MSI descriptors of a device in the default irqdomain
* @dev: Device to free the descriptors
*/
static inline void msi_free_msi_descs(struct device *dev)
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -19,6 +19,18 @@

#include "internals.h"

+/**
+ * struct msi_ctrl - MSI internal management control structure
+ * @domid: ID of the domain on which management operations should be done
+ * @first: First (hardware) slot index to operate on
+ * @last: Last (hardware) slot index to operate on
+ */
+struct msi_ctrl {
+ unsigned int domid;
+ unsigned int first;
+ unsigned int last;
+};
+
/* Invalid Xarray index which is outside of any searchable range */
#define MSI_XA_MAX_INDEX (ULONG_MAX - 1)
/* The maximum domain size */
@@ -151,22 +163,29 @@ static bool msi_desc_match(struct msi_de
return false;
}

-/**
- * msi_free_msi_descs_range - Free MSI descriptors of a device
- * @dev: Device to free the descriptors
- * @first_index: Index to start freeing from
- * @last_index: Last index to be freed
- */
-void msi_free_msi_descs_range(struct device *dev, unsigned int first_index,
- unsigned int last_index)
+static bool msi_ctrl_valid(struct device *dev, struct msi_ctrl *ctrl)
+{
+ if (WARN_ON_ONCE(ctrl->domid >= MSI_MAX_DEVICE_IRQDOMAINS ||
+ ctrl->first > ctrl->last ||
+ ctrl->first > MSI_MAX_INDEX ||
+ ctrl->last > MSI_MAX_INDEX))
+ return false;
+ return true;
+}
+
+static void msi_domain_free_descs(struct device *dev, struct msi_ctrl *ctrl)
{
- struct xarray *xa = &dev->msi.data->__domains[MSI_DEFAULT_DOMAIN].store;
struct msi_desc *desc;
+ struct xarray *xa;
unsigned long idx;

lockdep_assert_held(&dev->msi.data->mutex);

- xa_for_each_range(xa, idx, desc, first_index, last_index) {
+ if (!msi_ctrl_valid(dev, ctrl))
+ return;
+
+ xa = &dev->msi.data->__domains[ctrl->domid].store;
+ xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
xa_erase(xa, idx);

/* Leak the descriptor when it is still referenced */
@@ -176,6 +195,25 @@ void msi_free_msi_descs_range(struct dev
}
}

+/**
+ * msi_domain_free_msi_descs_range - Free a range of MSI descriptors of a device in an irqdomain
+ * @dev: Device for which to free the descriptors
+ * @domid: Id of the domain to operate on
+ * @first: Index to start freeing from (inclusive)
+ * @last: Last index to be freed (inclusive)
+ */
+void msi_domain_free_msi_descs_range(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_descs(dev, &ctrl);
+}
+
void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
{
*msg = entry->msg;