diff options
Diffstat (limited to 'drivers/vfio/vfio_iommu_type1.c')
-rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 1d48e62f4f52..0d5b667c0e65 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -53,10 +53,16 @@ module_param_named(disable_hugepages, 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; }; @@ -384,6 +390,7 @@ static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *dma) 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) @@ -584,12 +591,18 @@ static int vfio_dma_do_map(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; @@ -905,6 +918,7 @@ static void *vfio_iommu_type1_open(unsigned long arg) INIT_LIST_HEAD(&iommu->domain_list); iommu->dma_list = RB_ROOT; + iommu->dma_avail = dma_entry_limit; mutex_init(&iommu->lock); return iommu; |