|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | NOTES | SEE ALSO | COLOPHON |
|
|
|
io_uring_pr...iles_update(3) liburing Manual io_uring_pr...iles_update(3)
io_uring_prep_files_update - prepare a registered file update
request
#include <liburing.h>
void io_uring_prep_files_update(struct io_uring_sqe *sqe,
int *fds,
unsigned nr_fds,
int offset);
The io_uring_prep_files_update(3) function prepares a request for
updating a number of previously registered file descriptors. The
submission queue entry sqe is setup to use the file descriptor
array pointed to by fds and of nr_fds in length to update that
amount of previously registered files starting at offset offset.
Once a previously registered file is updated with a new one, the
existing entry is updated and then removed from the table. This
operation is equivalent to first unregistering that entry and then
inserting a new one, just bundled into one combined operation.
If offset is specified as IORING_FILE_INDEX_ALLOC, io_uring will
allocate free direct descriptors instead of having the application
to pass, and store allocated direct descriptors into fds array,
cqe->res will return the number of direct descriptors allocated.
None
These are the errors that are reported in the CQE res field. On
success, res will contain the number of successfully updated file
descriptors. On error, the following errors can occur.
-ENOMEM
The kernel was unable to allocate memory for the request.
-EINVAL
One of the fields set in the SQE was invalid.
-EFAULT
The kernel was unable to copy in the memory pointed to by
fds.
-EBADF On of the descriptors located in fds didn't refer to a
valid file descriptor, or one of the file descriptors in
the array referred to an io_uring instance.
-EOVERFLOW
The product of offset and nr_fds exceed the valid amount or
overflowed.
As with any request that passes in data in a struct, that data
must remain valid until the request has been successfully
submitted. It need not remain valid until completion. Once a
request has been submitted, the in-kernel state is stable. Very
early kernels (5.4 and earlier) required state to be stable until
the completion occurred. Applications can test for this behavior
by inspecting the IORING_FEAT_SUBMIT_STABLE flag passed back from
io_uring_queue_init_params(3).
io_uring_get_sqe(3), io_uring_submit(3), io_uring_register(2)
This page is part of the liburing (A library for io_uring)
project. Information about the project can be found at
⟨https://github.com/axboe/liburing⟩. If you have a bug report for
this manual page, send it to [email protected]. This page
was obtained from the project's upstream Git repository
⟨https://github.com/axboe/liburing⟩ on 2025-08-11. (At that time,
the date of the most recent commit that was found in the
repository was 2025-08-02.) If you discover any rendering
problems in this HTML version of the page, or you believe there is
a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
[email protected]
liburing-2.2 March 13, 2022 io_uring_pr...iles_update(3)
Pages that refer to this page: io_uring_prep_files_update(3)
|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|