[tip: irq/core] genirq/msi: Move xarray into a separate struct and create an array

From: tip-bot2 for Thomas Gleixner
Date: Mon Dec 05 2022 - 13:28:54 EST


The following commit has been merged into the irq/core branch of tip:

Commit-ID: f1139f905bd2d8bec59be0c1404b592279ae0ac9
Gitweb: https://git.kernel.org/tip/f1139f905bd2d8bec59be0c1404b592279ae0ac9
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 25 Nov 2022 00:24:20 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Mon, 05 Dec 2022 19:20:59 +01:00

genirq/msi: Move xarray into a separate struct and create an array

The upcoming support for multiple MSI domains per device requires storage
for the MSI descriptors and in a second step storage for the irqdomain
pointers.

Move the xarray into a separate data structure msi_dev_domain and create an
array with size 1 in msi_device_data, which can be expanded later when the
support for per device domains is implemented.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Acked-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221124230313.864887773@xxxxxxxxxxxxx

---
include/linux/msi.h | 13 +++++++++++--
include/linux/msi_api.h | 8 ++++++++
kernel/irq/msi.c | 32 ++++++++++++++++++++++----------
3 files changed, 41 insertions(+), 12 deletions(-)

diff --git a/include/linux/msi.h b/include/linux/msi.h
index 9f72494..f7b9c41 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -173,19 +173,28 @@ enum msi_desc_filter {
MSI_DESC_ASSOCIATED,
};

+
+/**
+ * struct msi_dev_domain - The internals of MSI domain info per device
+ * @store: Xarray for storing MSI descriptor pointers
+ */
+struct msi_dev_domain {
+ struct xarray store;
+};
+
/**
* msi_device_data - MSI per device data
* @properties: MSI properties which are interesting to drivers
* @platform_data: Platform-MSI specific data
* @mutex: Mutex protecting the MSI descriptor store
- * @__store: Xarray for storing MSI descriptor pointers
+ * @__domains: Internal data for per device MSI domains
* @__iter_idx: Index to search the next entry for iterators
*/
struct msi_device_data {
unsigned long properties;
struct platform_msi_priv_data *platform_data;
struct mutex mutex;
- struct xarray __store;
+ struct msi_dev_domain __domains[MSI_MAX_DEVICE_IRQDOMAINS];
unsigned long __iter_idx;
};

diff --git a/include/linux/msi_api.h b/include/linux/msi_api.h
index 57d27cf..4dbbce6 100644
--- a/include/linux/msi_api.h
+++ b/include/linux/msi_api.h
@@ -10,6 +10,14 @@

struct device;

+/*
+ * Per device interrupt domain related constants.
+ */
+enum msi_domain_ids {
+ MSI_DEFAULT_DOMAIN,
+ MSI_MAX_DEVICE_IRQDOMAINS,
+};
+
unsigned int msi_get_virq(struct device *dev, unsigned int index);

#endif
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 5939dc6..c2bc94e 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -60,10 +60,11 @@ static void msi_free_desc(struct msi_desc *desc)

static int msi_insert_desc(struct msi_device_data *md, struct msi_desc *desc, unsigned int index)
{
+ struct xarray *xa = &md->__domains[MSI_DEFAULT_DOMAIN].store;
int ret;

desc->msi_index = index;
- ret = xa_insert(&md->__store, index, desc, GFP_KERNEL);
+ ret = xa_insert(xa, index, desc, GFP_KERNEL);
if (ret)
msi_free_desc(desc);
return ret;
@@ -147,7 +148,7 @@ static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter)
void msi_free_msi_descs_range(struct device *dev, unsigned int first_index,
unsigned int last_index)
{
- struct xarray *xa = &dev->msi.data->__store;
+ struct xarray *xa = &dev->msi.data->__domains[MSI_DEFAULT_DOMAIN].store;
struct msi_desc *desc;
unsigned long idx;

@@ -179,9 +180,12 @@ EXPORT_SYMBOL_GPL(get_cached_msi_msg);
static void msi_device_data_release(struct device *dev, void *res)
{
struct msi_device_data *md = res;
+ int i;

- WARN_ON_ONCE(!xa_empty(&md->__store));
- xa_destroy(&md->__store);
+ for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++) {
+ WARN_ON_ONCE(!xa_empty(&md->__domains[i].store));
+ xa_destroy(&md->__domains[i].store);
+ }
dev->msi.data = NULL;
}

@@ -198,7 +202,7 @@ static void msi_device_data_release(struct device *dev, void *res)
int msi_setup_device_data(struct device *dev)
{
struct msi_device_data *md;
- int ret;
+ int ret, i;

if (dev->msi.data)
return 0;
@@ -213,7 +217,9 @@ int msi_setup_device_data(struct device *dev)
return ret;
}

- xa_init(&md->__store);
+ for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++)
+ xa_init(&md->__domains[i].store);
+
mutex_init(&md->mutex);
dev->msi.data = md;
devres_add(dev, md);
@@ -236,7 +242,7 @@ EXPORT_SYMBOL_GPL(msi_lock_descs);
*/
void msi_unlock_descs(struct device *dev)
{
- /* Invalidate the index wich was cached by the iterator */
+ /* Invalidate the index which was cached by the iterator */
dev->msi.data->__iter_idx = MSI_MAX_INDEX;
mutex_unlock(&dev->msi.data->mutex);
}
@@ -244,9 +250,10 @@ EXPORT_SYMBOL_GPL(msi_unlock_descs);

static struct msi_desc *msi_find_desc(struct msi_device_data *md, enum msi_desc_filter filter)
{
+ struct xarray *xa = &md->__domains[MSI_DEFAULT_DOMAIN].store;
struct msi_desc *desc;

- xa_for_each_start(&md->__store, md->__iter_idx, desc, md->__iter_idx) {
+ xa_for_each_start(xa, md->__iter_idx, desc, md->__iter_idx) {
if (msi_desc_match(desc, filter))
return desc;
}
@@ -320,6 +327,7 @@ unsigned int msi_get_virq(struct device *dev, unsigned int index)
{
struct msi_desc *desc;
unsigned int ret = 0;
+ struct xarray *xa;
bool pcimsi;

if (!dev->msi.data)
@@ -328,7 +336,8 @@ unsigned int msi_get_virq(struct device *dev, unsigned int index)
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);
+ xa = &dev->msi.data->__domains[MSI_DEFAULT_DOMAIN].store;
+ desc = xa_load(xa, pcimsi ? 0 : index);
if (desc && desc->irq) {
/*
* PCI-MSI has only one descriptor for multiple interrupts.
@@ -707,6 +716,7 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
struct msi_desc *desc;
+ struct xarray *xa;
int ret, virq;

msi_lock_descs(dev);
@@ -714,8 +724,10 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
if (ret)
goto unlock;

+ xa = &dev->msi.data->__domains[MSI_DEFAULT_DOMAIN].store;
+
for (virq = virq_base; virq < virq_base + nvec; virq++) {
- desc = xa_load(&dev->msi.data->__store, virq);
+ desc = xa_load(xa, virq);
desc->irq = virq;

ops->set_desc(arg, desc);