[PATCH v4 2/5] PCI: hv: Allow dynamic MSI-X vector allocation
From: Shradha Gupta <hidden>
Date: 2025-05-27 15:58:10
Also in:
linux-hyperv, linux-pci, linux-rdma, lkml
Subsystem:
hyper-v/azure core and drivers, pci native host bridge and endpoint drivers, pci subsystem, the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Lorenzo Pieralisi, Krzysztof Wilczyński, Manivannan Sadhasivam, Bjorn Helgaas, Linus Torvalds
Allow dynamic MSI-X vector allocation for pci_hyperv PCI controller by adding support for the flag MSI_FLAG_PCI_MSIX_ALLOC_DYN and using pci_msix_prepare_desc() to prepare the MSI-X descriptors. Feature support added for both x86 and ARM64 Signed-off-by: Shradha Gupta <redacted> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> --- Changes in v4: * use the same prepare_desc() callback for arm and x86 --- Changes in v3: * Add arm64 support --- Changes in v2: * split the patch to keep changes in PCI and pci_hyperv controller seperate * replace strings "pci vectors" by "MSI-X vectors" --- drivers/pci/controller/pci-hyperv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletions(-)
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index ac27bda5ba26..0c790f35ad0e 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c@@ -2063,6 +2063,7 @@ static struct irq_chip hv_msi_irq_chip = { static struct msi_domain_ops hv_msi_ops = { .msi_prepare = hv_msi_prepare, .msi_free = hv_msi_free, + .prepare_desc = pci_msix_prepare_desc, }; /**
@@ -2084,7 +2085,7 @@ static int hv_pcie_init_irq_domain(struct hv_pcibus_device *hbus) hbus->msi_info.ops = &hv_msi_ops; hbus->msi_info.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_MULTI_PCI_MSI | - MSI_FLAG_PCI_MSIX); + MSI_FLAG_PCI_MSIX | MSI_FLAG_PCI_MSIX_ALLOC_DYN); hbus->msi_info.handler = FLOW_HANDLER; hbus->msi_info.handler_name = FLOW_NAME; hbus->msi_info.data = hbus;
--
2.34.1