From 73103975425786ebdb6c4d2868ecf26f391fb77e Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Wed, 1 May 2019 14:58:23 +0100 Subject: [PATCH] irqchip/gic-v3-mbi: Don't map the MSI page in mbi_compose_m{b, s}i_msg() The functions mbi_compose_m{b, s}i_msg may be called from non-preemptible context. However, on RT, iommu_dma_map_msi_msg() requires to be called from a preemptible context. A recent patch split iommu_dma_map_msi_msg in two new functions: one that should be called in preemptible context, the other does not have any requirement. The GICv3 MSI driver is reworked to avoid executing preemptible code in non-preemptible context. This can be achieved by preparing the MSI mapping when allocating the MSI interrupt. Signed-off-by: Julien Grall [maz: only call iommu_dma_prepare_msi once, fix commit log accordingly] Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3-mbi.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-mbi.c b/drivers/irqchip/irq-gic-v3-mbi.c index fbfa7ff6deb1..563a9b366294 100644 --- a/drivers/irqchip/irq-gic-v3-mbi.c +++ b/drivers/irqchip/irq-gic-v3-mbi.c @@ -84,6 +84,7 @@ static void mbi_free_msi(struct mbi_range *mbi, unsigned int hwirq, static int mbi_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, unsigned int nr_irqs, void *args) { + msi_alloc_info_t *info = args; struct mbi_range *mbi = NULL; int hwirq, offset, i, err = 0; @@ -104,6 +105,11 @@ static int mbi_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, hwirq = mbi->spi_start + offset; + err = iommu_dma_prepare_msi(info->desc, + mbi_phys_base + GICD_SETSPI_NSR); + if (err) + return err; + for (i = 0; i < nr_irqs; i++) { err = mbi_irq_gic_domain_alloc(domain, virq + i, hwirq + i); if (err) @@ -142,7 +148,7 @@ static void mbi_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) msg[0].address_lo = lower_32_bits(mbi_phys_base + GICD_SETSPI_NSR); msg[0].data = data->parent_data->hwirq; - iommu_dma_map_msi_msg(data->irq, msg); + iommu_dma_compose_msi_msg(irq_data_get_msi_desc(data), msg); } #ifdef CONFIG_PCI_MSI @@ -202,7 +208,7 @@ static void mbi_compose_mbi_msg(struct irq_data *data, struct msi_msg *msg) msg[1].address_lo = lower_32_bits(mbi_phys_base + GICD_CLRSPI_NSR); msg[1].data = data->parent_data->hwirq; - iommu_dma_map_msi_msg(data->irq, &msg[1]); + iommu_dma_compose_msi_msg(irq_data_get_msi_desc(data), &msg[1]); } /* Platform-MSI specific irqchip */