[patch 12/20] genirq/msi: Make descriptor freeing domain aware

From: Thomas Gleixner
Date: Fri Nov 11 2022 - 09:02:59 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>
---
include/linux/msi.h | 22 ++++++++++++++++---
kernel/irq/msi.c | 60 ++++++++++++++++++++++++++++++++++++++++++----------
2 files changed, 68 insertions(+), 14 deletions(-)

--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -277,7 +277,8 @@ static inline void msi_desc_set_iommu_co
int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid,
struct msi_desc *init_desc);
/**
- * msi_insert_msi_desc - Allocate and initialize a MSI descriptor in the default domain
+ * msi_insert_msi_desc - Allocate and initialize a MSI descriptor in the default irqdomain
+ *
* @dev: Pointer to the device for which the descriptor is allocated
* @init_desc: Pointer to an MSI descriptor to initialize the new descriptor
*
@@ -288,10 +289,25 @@ 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_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 MSI descriptors of a device
+ * 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;
+};
+
static inline int msi_sysfs_create_group(struct device *dev);

/* Invalid XA index which is outside of any searchable range */
@@ -189,25 +201,32 @@ 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->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->__store;
struct msi_desc *desc;
unsigned long idx;
+ int base;
+
+ lockdep_assert_held(&dev->msi.data->mutex);

- if (WARN_ON_ONCE(first_index >= MSI_MAX_INDEX || last_index >= MSI_MAX_INDEX))
+ if (!msi_ctrl_valid(dev, ctrl))
return;

- lockdep_assert_held(&dev->msi.data->mutex);
+ base = msi_get_domain_base_index(dev, ctrl->domid);
+ if (base < 0)
+ return;

- xa_for_each_range(xa, idx, desc, first_index, last_index) {
+ xa_for_each_range(xa, idx, desc, ctrl->first + base, ctrl->last + base) {
xa_erase(xa, idx);

/* Leak the descriptor when it is still referenced */
@@ -217,6 +236,25 @@ 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;