From 85a8dfc57a0b96785881735e09a61a0fde911ca4 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 26 Aug 2020 13:16:59 +0200 Subject: [PATCH] iommm/vt-d: Store irq domain in struct device As a first step to make X86 utilize the direct MSI irq domain operations store the irq domain pointer in the device struct when a device is probed. This is done from dmar_pci_bus_add_dev() because it has to work even when DMA remapping is disabled. It only overrides the irqdomain of devices which are handled by a regular PCI/MSI irq domain which protects PCI devices behind special busses like VMD which have their own irq domain. No functional change. It just avoids the redirection through arch_*_msi_irqs() and allows the PCI/MSI core to directly invoke the irq domain alloc/free functions instead of having to look up the irq domain for every single MSI interupt. Signed-off-by: Thomas Gleixner Acked-by: Joerg Roedel Link: https://lore.kernel.org/r/20200826112333.714566121@linutronix.de --- drivers/iommu/intel/dmar.c | 3 +++ drivers/iommu/intel/irq_remapping.c | 16 ++++++++++++++++ include/linux/intel-iommu.h | 7 +++++++ 3 files changed, 26 insertions(+) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 93e6345..4dc09ed 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -316,6 +316,9 @@ static int dmar_pci_bus_add_dev(struct dmar_pci_notify_info *info) if (ret < 0 && dmar_dev_scope_status == 0) dmar_dev_scope_status = ret; + if (ret >= 0) + intel_irq_remap_add_device(info); + return ret; } diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c index d9db2f3..68692a4 100644 --- a/drivers/iommu/intel/irq_remapping.c +++ b/drivers/iommu/intel/irq_remapping.c @@ -1092,6 +1092,22 @@ error: return -1; } +/* + * Store the MSI remapping domain pointer in the device if enabled. + * + * This is called from dmar_pci_bus_add_dev() so it works even when DMA + * remapping is disabled. Only update the pointer if the device is not + * already handled by a non default PCI/MSI interrupt domain. This protects + * e.g. VMD devices. + */ +void intel_irq_remap_add_device(struct dmar_pci_notify_info *info) +{ + if (!irq_remapping_enabled || pci_dev_has_special_msi_domain(info->dev)) + return; + + dev_set_msi_domain(&info->dev->dev, map_dev_to_ir(info->dev)); +} + static void prepare_irte(struct irte *irte, int vector, unsigned int dest) { memset(irte, 0, sizeof(*irte)); diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index b1ed2f2..46f5aaa 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -425,6 +425,8 @@ struct q_inval { int free_cnt; }; +struct dmar_pci_notify_info; + #ifdef CONFIG_IRQ_REMAP /* 1MB - maximum possible interrupt remapping table size */ #define INTR_REMAP_PAGE_ORDER 8 @@ -439,6 +441,11 @@ struct ir_table { struct irte *base; unsigned long *bitmap; }; + +void intel_irq_remap_add_device(struct dmar_pci_notify_info *info); +#else +static inline void +intel_irq_remap_add_device(struct dmar_pci_notify_info *info) { } #endif struct iommu_flush { -- 2.7.4