kernel/linux.git/io_uring/openclose.h, branch v6.19.11

io_uring: add support for IORING_OP_PIPE

2025-04-21T11:06:58+00:00

This works just like pipe2(2), except it also supports fixed file descriptors. Used in a similar fashion as for other fd instantiating opcodes (like accept, socket, open, etc), where sqe->file_slot is set appropriately if two direct descriptors are desired rather than a set of normal file descriptors. sqe->addr must be set to a pointer to an array of 2 integers, which is where the fixed/normal file descriptors are copied to. sqe->pipe_flags contains flags, same as what is allowed for pipe2(2). Future expansion of per-op private flags can go in sqe->ioprio, like we do for other opcodes that take both a "syscall" flag set and an io_uring opcode specific flag set. Signed-off-by: Jens Axboe

io_uring/openclose: add support for IORING_OP_FIXED_FD_INSTALL

2023-12-12T14:42:57+00:00

io_uring can currently open/close regular files or fixed/direct descriptors. Or you can instantiate a fixed descriptor from a regular one, and then close the regular descriptor. But you currently can't turn a purely fixed/direct descriptor into a regular file descriptor. IORING_OP_FIXED_FD_INSTALL adds support for installing a direct descriptor into the normal file table, just like receiving a file descriptor or opening a new file would do. This is all nicely abstracted into receive_fd(), and hence adding support for this is truly trivial. Since direct descriptors are only usable within io_uring itself, it can be useful to turn them into real file descriptors if they ever need to be accessed via normal syscalls. This can either be a transitory thing, or just a permanent transition for a given direct descriptor. By default, new fds are installed with O_CLOEXEC set. The application can disable O_CLOEXEC by setting IORING_FIXED_FD_NO_CLOEXEC in the sqe->install_fd_flags member. Suggested-by: Christian Brauner Reviewed-by: Christian Brauner Signed-off-by: Jens Axboe

io_uring: split out fixed file installation and removal

2022-07-25T00:39:16+00:00

Put it with the filetable code, which is where it belongs. While doing so, have the helpers take a ctx rather than an io_kiocb. It doesn't make sense to use a request, as it's not an operation on the request itself. It applies to the ring itself. Signed-off-by: Jens Axboe

io_uring: split out open/close operations

2022-07-25T00:39:11+00:00

Signed-off-by: Jens Axboe