When an MSI doorbell is located downstream of an IOMMU, it is required to swizzle the physical address with an appropriately-mapped IOVA for any device attached to one of our DMA ops domain. At the moment, the allocation of the mapping may be done when composing the message. However, the composing may be done in non-preemtible context while the allocation requires to be called from preemptible context. A follow-up change will split the current logic in two functions requiring to keep an IOMMU cookie per MSI. A new field is introduced in msi_desc to store an IOMMU cookie. As the cookie may not be required in some configuration, the field is protected under a new config CONFIG_IRQ_MSI_IOMMU. A pair of helpers has also been introduced to access the field.
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| @@ -86,6 +86,9 @@ struct msi_desc { · 85 unmodified lines | ||
| 86 | 86 | struct device *dev; |
| 87 | 87 | struct msi_msg msg; |
| 88 | 88 | struct irq_affinity_desc *affinity; |
| 89 | +#ifdef CONFIG_IRQ_MSI_IOMMU | |
| 90 | + const void *iommu_cookie; | |
| 91 | +#endif | |
| 89 | 92 | |
| 90 | 93 | union { |
| 91 | 94 | /* PCI MSI/X specific data */ |
| @@ -129,6 +132,29 @@ struct msi_desc { · 37 unmodified lines | ||
| 129 | 132 | #define for_each_msi_entry_safe(desc, tmp, dev) \ |
| 130 | 133 | list_for_each_entry_safe((desc), (tmp), dev_to_msi_list((dev)), list) |
| 131 | 134 | |
| 135 | +#ifdef CONFIG_IRQ_MSI_IOMMU | |
| 136 | +static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc) | |
| 137 | +{ | |
| 138 | + return desc->iommu_cookie; | |
| 139 | +} | |
| 140 | + | |
| 141 | +static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc, | |
| 142 | + const void *iommu_cookie) | |
| 143 | +{ | |
| 144 | + desc->iommu_cookie = iommu_cookie; | |
| 145 | +} | |
| 146 | +#else | |
| 147 | +static inline const void *msi_desc_get_iommu_cookie(struct msi_desc *desc) | |
| 148 | +{ | |
| 149 | + return NULL; | |
| 150 | +} | |
| 151 | + | |
| 152 | +static inline void msi_desc_set_iommu_cookie(struct msi_desc *desc, | |
| 153 | + const void *iommu_cookie) | |
| 154 | +{ | |
| 155 | +} | |
| 156 | +#endif | |
| 157 | + | |
| 132 | 158 | #ifdef CONFIG_PCI_MSI |
| 133 | 159 | #define first_pci_msi_entry(pdev) first_msi_entry(&(pdev)->dev) |
| 134 | 160 | #define for_each_pci_msi_entry(desc, pdev) \ |