[tip: irq/core] PCI/MSI: Provide pci_ims_alloc/free_irq()
From: tip-bot2 for Thomas Gleixner
Date: Mon Dec 05 2022 - 16:42:15 EST
The following commit has been merged into the irq/core branch of tip:
Commit-ID: c9e5bea273834a63b5e9ba90ad94b305ba50704e
Gitweb: https://git.kernel.org/tip/c9e5bea273834a63b5e9ba90ad94b305ba50704e
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 25 Nov 2022 00:26:31 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Mon, 05 Dec 2022 22:22:35 +01:00
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@xxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Acked-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221124232326.961711347@xxxxxxxxxxxxx
---
drivers/pci/msi/api.c | 50 ++++++++++++++++++++++++++++++++++++++++++-
include/linux/pci.h | 3 +++-
2 files changed, 53 insertions(+)
diff --git a/drivers/pci/msi/api.c b/drivers/pci/msi/api.c
index c8816db..b8009aa 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
*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 1592b63..aa514b5 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2491,6 +2491,9 @@ struct msi_domain_template;
bool pci_create_ims_domain(struct pci_dev *pdev, const struct msi_domain_template *template,
unsigned int hwsize, void *data);
+struct msi_map pci_ims_alloc_irq(struct pci_dev *pdev, union msi_instance_cookie *icookie,
+ const struct irq_affinity_desc *affdesc);
+void pci_ims_free_irq(struct pci_dev *pdev, struct msi_map map);
#include <linux/dma-mapping.h>