NAME

       io_uring_register_file_alloc_range - set range for fixed file allocations

SYNOPSIS

       #include <liburing.h>

       int io_uring_register_file_alloc_range(struct io_uring *ring,
                                              unsigned off,
                                              unsigned len);

DESCRIPTION

       The io_uring_register_file_alloc_range(3) function sets the allowable range for fixed file
       index allocations within the kernel. When requests that can instantiate a new  fixed  file
       are used with IORING_FILE_INDEX_ALLOC , the application is asking the kernel to allocate a
       new fixed file descriptor rather than pass in a specific value for one.  By  default,  the
       kernel  will  pick any available fixed file descriptor within the range available. Calling
       this function with off  set  to  the  starting  offset  and  len  set  to  the  number  of
       descriptors, the application can limit the allocated descriptors to that particular range.
       This effectively allows the application to set aside a range just for dynamic allocations,
       with the remainder being used for specific values.

       The   application   must   have   registered  a  fixed  file  table  upfront,  eg  through
       io_uring_register_files(3) or io_uring_register_files_sparse(3).

       Available since 6.0.

RETURN VALUE

       On success io_uring_register_buf_ring(3) returns 0. On failure it returns -errno.

SEE ALSO

       io_uring_register_files(3)  io_uring_prep_accept_direct(3)  io_uring_prep_openat_direct(3)
       io_uring_prep_socket_direct(3)