zx_iommu_create

NAME

Create a new IOMMU object in the kernel.

SYNOPSIS

#include <zircon/syscalls.h>

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.