[PATCH v2 3/7] Revert "PCI/MSI: Provide IMS (Interrupt Message Store) support"

From: Bjorn Helgaas
Date: Wed Apr 10 2024 - 18:14:13 EST


From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

This reverts commit 0194425af0c87acaad457989a2c6d90dba58e776.

IMS (Interrupt Message Store) support appeared in v6.2, but there are no
users yet.

Remove it for now. We can add it back when a user comes along. If this is
re-added later, the relevant part of 41efa431244f ("PCI/MSI: Provide stubs
for IMS functions") should be squashed into it.

Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
---
drivers/pci/msi/irqdomain.c | 59 -------------------------------------
include/linux/pci.h | 5 ----
2 files changed, 64 deletions(-)

diff --git a/drivers/pci/msi/irqdomain.c b/drivers/pci/msi/irqdomain.c
index cfd84a899c82..03d2dd25790d 100644
--- a/drivers/pci/msi/irqdomain.c
+++ b/drivers/pci/msi/irqdomain.c
@@ -355,65 +355,6 @@ bool pci_msi_domain_supports(struct pci_dev *pdev, unsigned int feature_mask,
return (supported & feature_mask) == feature_mask;
}

-/**
- * pci_create_ims_domain - Create a secondary IMS domain for a PCI device
- * @pdev: The PCI device to operate on
- * @template: The MSI info template which describes the domain
- * @hwsize: The size of the hardware entry table or 0 if the domain
- * is purely software managed
- * @data: Optional pointer to domain specific data to be stored
- * in msi_domain_info::data
- *
- * Return: True on success, false otherwise
- *
- * An IMS domain is expected to have the following constraints:
- * - The index space is managed by the core code
- *
- * - There is no requirement for consecutive index ranges
- *
- * - The interrupt chip must provide the following callbacks:
- * - irq_mask()
- * - irq_unmask()
- * - irq_write_msi_msg()
- *
- * - The interrupt chip must provide the following optional callbacks
- * when the irq_mask(), irq_unmask() and irq_write_msi_msg() callbacks
- * cannot operate directly on hardware, e.g. in the case that the
- * interrupt message store is in queue memory:
- * - irq_bus_lock()
- * - irq_bus_unlock()
- *
- * These callbacks are invoked from preemptible task context and are
- * allowed to sleep. In this case the mandatory callbacks above just
- * store the information. The irq_bus_unlock() callback is supposed
- * to make the change effective before returning.
- *
- * - Interrupt affinity setting is handled by the underlying parent
- * interrupt domain and communicated to the IMS domain via
- * irq_write_msi_msg().
- *
- * The domain is automatically destroyed when the PCI device is removed.
- */
-bool pci_create_ims_domain(struct pci_dev *pdev, const struct msi_domain_template *template,
- unsigned int hwsize, void *data)
-{
- struct irq_domain *domain = dev_get_msi_domain(&pdev->dev);
-
- if (!domain || !irq_domain_is_msi_parent(domain))
- return false;
-
- if (template->info.bus_token != DOMAIN_BUS_PCI_DEVICE_IMS ||
- !(template->info.flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS) ||
- !(template->info.flags & MSI_FLAG_FREE_MSI_DESCS) ||
- !template->chip.irq_mask || !template->chip.irq_unmask ||
- !template->chip.irq_write_msi_msg || template->chip.irq_set_affinity)
- return false;
-
- return msi_create_device_irq_domain(&pdev->dev, MSI_SECONDARY_DOMAIN, template,
- hwsize, data, NULL);
-}
-EXPORT_SYMBOL_GPL(pci_create_ims_domain);
-
/*
* Users of the generic MSI infrastructure expect a device to have a single ID,
* so with DMA aliases we have to pick the least-worst compromise. Devices with
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3deb3e42d990..98fb20bcd054 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -2664,11 +2664,6 @@ static inline bool pci_is_thunderbolt_attached(struct pci_dev *pdev)
void pci_uevent_ers(struct pci_dev *pdev, enum pci_ers_result err_type);
#endif

-struct msi_domain_template;
-
-bool pci_create_ims_domain(struct pci_dev *pdev, const struct msi_domain_template *template,
- unsigned int hwsize, void *data);
-
#include <linux/dma-mapping.h>

#define pci_printk(level, pdev, fmt, arg...) \
--
2.34.1