MODULE_PARM_DESC(disable_hugepages,
"Disable VFIO IOMMU support for IOMMU hugepages.");
+static unsigned int dma_entry_limit __read_mostly = U16_MAX;
+module_param_named(dma_entry_limit, dma_entry_limit, uint, 0644);
+MODULE_PARM_DESC(dma_entry_limit,
+ "Maximum number of user DMA mappings per container (65535).");
+
struct vfio_iommu {
struct list_head domain_list;
struct mutex lock;
struct rb_root dma_list;
+ unsigned int dma_avail;
bool v2;
bool nesting;
};
vfio_unmap_unpin(iommu, dma);
vfio_unlink_dma(iommu, dma);
kfree(dma);
+ iommu->dma_avail++;
}
static unsigned long vfio_pgsize_bitmap(struct vfio_iommu *iommu)
return -EEXIST;
}
+ if (!iommu->dma_avail) {
+ mutex_unlock(&iommu->lock);
+ return -ENOSPC;
+ }
+
dma = kzalloc(sizeof(*dma), GFP_KERNEL);
if (!dma) {
mutex_unlock(&iommu->lock);
return -ENOMEM;
}
+ iommu->dma_avail--;
dma->iova = iova;
dma->vaddr = vaddr;
dma->prot = prot;
INIT_LIST_HEAD(&iommu->domain_list);
iommu->dma_list = RB_ROOT;
+ iommu->dma_avail = dma_entry_limit;
mutex_init(&iommu->lock);
return iommu;