# zx_iommu_create ## NAME iommu_create - create a new IOMMU object in the kernel ## SYNOPSIS ``` #include zx_status_t zx_iommu_create(zx_handle_t resource, uint32_t type, const void* desc, size_t desc_size, zx_handle_t* out); ``` ## DESCRIPTION `zx_iommu_create()` creates a new object in the kernel representing an IOMMU device. The value of *type* determines the interpretation of *desc*. See below for details about the values of *type*. Upon success, a handle for the new IOMMU is returned. This handle will have rights **ZX_RIGHT_DUPLICATE** and **ZX_RIGHT_TRANSFER**. ### *type* = **ZX_IOMMU_TYPE_DUMMY** This type represents a no-op IOMMU. It provides no hardware-level protections against unauthorized access to memory. It does allow pinning of physical memory pages, to prevent the reuse of a page until the driver using the page says it is done with it. *desc* must be a valid pointer to a value of type `zx_iommu_desc_dummy_t`. *desc_size* must be `sizeof(zx_iommu_desc_dummy_t)`. ## RIGHTS *resource* must have resource kind **ZX_RSRC_KIND_ROOT**. ## RETURN VALUE `zx_iommu_create()` returns **ZX_OK** and a handle to the new IOMMU (via *out*) on success. In the event of failure, a negative error value is returned. ## ERRORS **ZX_ERR_BAD_HANDLE** *resource* is not a valid handle. **ZX_ERR_WRONG_TYPE** *resource* is not a resource handle. **ZX_ERR_ACCESS_DENIED** *resource* handle does not have sufficient privileges. **ZX_ERR_NOT_SUPPORTED** *type* is not a defined value or is not supported on this system. **ZX_ERR_INVALID_ARGS** *desc_size* is larger than **ZX_IOMMU_MAX_DESC_LEN**, *desc* is an invalid pointer, *out* is an invalid pointer, or the contents of *desc* are not valid for the given *type*. **ZX_ERR_NO_MEMORY** Failure due to lack of memory. There is no good way for userspace to handle this (unlikely) error. In a future build this error will no longer occur. ## SEE ALSO - [`zx_bti_create()`] - [`zx_bti_pin()`] - [`zx_pmt_unpin()`] [`zx_bti_create()`]: bti_create.md [`zx_bti_pin()`]: bti_pin.md [`zx_pmt_unpin()`]: pmt_unpin.md