zx_system_mexec_payload_get

Summary

Return a ZBI containing ZBI entries necessary to boot this system.

Declaration

#include <zircon/syscalls.h>

zx_status_t zx_system_mexec_payload_get(zx_handle_t resource,
                                        void* buffer,
                                        size_t buffer_size);

Description

zx_system_mexec_payload_get() accepts a resource handle and a pointer/length corresponding to an output buffer. The head of the buffer is overwritten with non-bootable ZBI containing a sequence of entries that should be appended to a ZBI before passing that image to zx_system_mexec(); the tail of the buffer is left untouched.

resource must be of type ZX_RSRC_KIND_SYSTEM with base ZX_RSRC_SYSTEM_MEXEC_BASE.

buffer and buffer_size must point to a buffer that is no longer than 16KiB.

To use the zx_system_mexec_payload_get() function, you must specify kernel.enable-debugging-syscalls=true on the kernel command line. Otherwise, the function returns ZX_ERR_NOT_SUPPORTED.

Rights

resource must have resource kind ZX_RSRC_KIND_SYSTEM with base ZX_RSRC_SYSTEM_MEXEC_BASE.

Return value

zx_system_mexec_payload_get() returns ZX_OK on success.

ZX_ERR_NOT_SUPPORTED kernel.enable-debugging-syscalls is not set to true on the kernel command line.

ZX_ERR_BUFFER_TOO_SMALL If the provided buffer is too small for the ZBI. In this case, the caller is expected to make the syscall again with a larger buffer.

See also