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authorThomas Gleixner <tglx@linutronix.de>2022-11-25 00:26:31 +0100
committerThomas Gleixner <tglx@linutronix.de>2022-12-05 22:22:35 +0100
commitc9e5bea273834a63b5e9ba90ad94b305ba50704e (patch)
treeef5fba1bb987636dd395aab8045ed5d91afcf5cd /drivers/pci
parent0194425af0c87acaad457989a2c6d90dba58e776 (diff)
PCI/MSI: Provide pci_ims_alloc/free_irq()
Single vector allocation which allocates the next free index in the IMS space. The free function releases. All allocated vectors are released also via pci_free_vectors() which is also releasing MSI/MSI-X vectors. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20221124232326.961711347@linutronix.de
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/msi/api.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index c8816db91e9c..b8009aa11f3c 100644
--- a/drivers/pci/msi/api.c
+++ b/drivers/pci/msi/api.c
@@ -366,6 +366,56 @@ const struct cpumask *pci_irq_get_affinity(struct pci_dev *dev, int nr)
EXPORT_SYMBOL(pci_irq_get_affinity);
/**
+ * pci_ims_alloc_irq - Allocate an interrupt on a PCI/IMS interrupt domain
+ * @dev: The PCI device to operate on
+ * @icookie: Pointer to an IMS implementation specific cookie for this
+ * IMS instance (PASID, queue ID, pointer...).
+ * The cookie content is copied into the MSI descriptor for the
+ * interrupt chip callbacks or domain specific setup functions.
+ * @affdesc: Optional pointer to an interrupt affinity descriptor
+ *
+ * There is no index for IMS allocations as IMS is an implementation
+ * specific storage and does not have any direct associations between
+ * index, which might be a pure software construct, and device
+ * functionality. This association is established by the driver either via
+ * the index - if there is a hardware table - or in case of purely software
+ * managed IMS implementation the association happens via the
+ * irq_write_msi_msg() callback of the implementation specific interrupt
+ * chip, which utilizes the provided @icookie to store the MSI message in
+ * the appropriate place.
+ *
+ * Return: A struct msi_map
+ *
+ * On success msi_map::index contains the allocated index (>= 0) and
+ * msi_map::virq the allocated Linux interrupt number (> 0).
+ *
+ * On fail msi_map::index contains the error code and msi_map::virq
+ * is set to 0.
+ */
+struct msi_map pci_ims_alloc_irq(struct pci_dev *dev, union msi_instance_cookie *icookie,
+ const struct irq_affinity_desc *affdesc)
+{
+ return msi_domain_alloc_irq_at(&dev->dev, MSI_SECONDARY_DOMAIN, MSI_ANY_INDEX,
+ affdesc, icookie);
+}
+EXPORT_SYMBOL_GPL(pci_ims_alloc_irq);
+
+/**
+ * pci_ims_free_irq - Allocate an interrupt on a PCI/IMS interrupt domain
+ * which was allocated via pci_ims_alloc_irq()
+ * @dev: The PCI device to operate on
+ * @map: A struct msi_map describing the interrupt to free as
+ * returned from pci_ims_alloc_irq()
+ */
+void pci_ims_free_irq(struct pci_dev *dev, struct msi_map map)
+{
+ if (WARN_ON_ONCE(map.index < 0 || map.virq <= 0))
+ return;
+ msi_domain_free_irqs_range(&dev->dev, MSI_SECONDARY_DOMAIN, map.index, map.index);
+}
+EXPORT_SYMBOL_GPL(pci_ims_free_irq);
+
+/**
* pci_free_irq_vectors() - Free previously allocated IRQs for a device
* @dev: the PCI device to operate on
*