From: Pavel Begunkov <[email protected]>
To: Jens Axboe <[email protected]>, io-uring <[email protected]>
Subject: [RFC] fixed files
Date: Sat, 8 Feb 2020 16:28:59 +0300 [thread overview]
Message-ID: <[email protected]> (raw)
Hi,
As you remember, splice(2) needs two fds, and it's a bit of a pain
finding a place for the second REQ_F_FIXED_FILE flag. So, I was
thinking, can we use the last (i.e. sign) bit to mark an fd as fixed? A
lot of userspace programs consider any negative result of open() as an
error, so it's more or less safe to reuse it.
e.g.
fill_sqe(fd) // is not fixed
fill_sqe(buf_idx | LAST_BIT) // fixed file
--
Pavel Begunkov
next reply other threads:[~2020-02-08 13:29 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-08 13:28 Pavel Begunkov [this message]
2020-02-08 20:15 ` [RFC] fixed files Jens Axboe
2020-02-09 12:18 ` Pavel Begunkov
2020-02-09 17:04 ` Jens Axboe
2020-02-09 17:53 ` Pavel Begunkov
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