JIRA: https://issues.redhat.com/browse/RHEL-27755
Conflicts: RHEL is missing commit 4e94ddfe2aab ("file: remove
__receive_fd()"), which changes the calling convention of receive_fd.
commit dc18b89ab113e9c6c7a529316ddf7029fb55132d
Author: Jens Axboe <axboe@kernel.dk>
Date: Thu Dec 7 20:06:02 2023 -0700
io_uring/openclose: add support for IORING_OP_FIXED_FD_INSTALL
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 <brauner@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2068237
commit f110ed8498afa6ff8e9a8c08fb26880e02117616
Author: Jens Axboe <axboe@kernel.dk>
Date: Mon Jun 13 04:42:56 2022 -0600
io_uring: split out fixed file installation and removal
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 <axboe@kernel.dk>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>