public inbox for [email protected]
 help / color / mirror / Atom feed
From: Pavel Begunkov <[email protected]>
To: Jens Axboe <[email protected]>, [email protected]
Subject: [PATCH v2 05/13] io_uring: further simplify do_read error parsing
Date: Thu,  4 Feb 2021 13:52:00 +0000	[thread overview]
Message-ID: <332f7a77b6790ded4df47b28cd9e60ba849b7de3.1612446019.git.asml.silence@gmail.com> (raw)
In-Reply-To: <[email protected]>

First, instead of checking iov_iter_count(iter) for 0 to find out that
all needed bytes were read, just compare returned code against io_size.
It's more reliable and arguably cleaner.

Also, place the half-read case into an else branch and delete an extra
label.

Signed-off-by: Pavel Begunkov <[email protected]>
---
 fs/io_uring.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 866e0ea83dbe..1d1fa1f77332 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3552,19 +3552,18 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,
 		/* some cases will consume bytes even on error returns */
 		iov_iter_revert(iter, io_size - iov_iter_count(iter));
 		ret = 0;
-		goto copy_iov;
-	} else if (ret <= 0) {
+	} else if (ret <= 0 || ret == io_size) {
 		/* make sure -ERESTARTSYS -> -EINTR is done */
 		goto done;
-	}
+	} else {
+		/* we did blocking attempt. no retry. */
+		if (!force_nonblock || (req->file->f_flags & O_NONBLOCK) ||
+		    !(req->flags & REQ_F_ISREG))
+			goto done;
 
-	/* read it all, or we did blocking attempt. no retry. */
-	if (!iov_iter_count(iter) || !force_nonblock ||
-	    (req->file->f_flags & O_NONBLOCK) || !(req->flags & REQ_F_ISREG))
-		goto done;
+		io_size -= ret;
+	}
 
-	io_size -= ret;
-copy_iov:
 	ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
 	if (ret2) {
 		ret = ret2;
-- 
2.24.0


  parent reply	other threads:[~2021-02-04 14:00 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-04 13:51 [PATCH v2 5.12 00/13] a second pack of 5.12 cleanups Pavel Begunkov
2021-02-04 13:51 ` [PATCH v2 01/13] io_uring: deduplicate core cancellations sequence Pavel Begunkov
2021-02-04 13:51 ` [PATCH v2 02/13] io_uring: refactor scheduling in io_cqring_wait Pavel Begunkov
2021-02-04 13:51 ` [PATCH v2 03/13] io_uring: refactor io_cqring_wait Pavel Begunkov
2021-02-04 13:51 ` [PATCH v2 04/13] io_uring: refactor io_read for unsupported nowait Pavel Begunkov
2021-02-04 13:52 ` Pavel Begunkov [this message]
2021-02-04 13:52 ` [PATCH v2 06/13] io_uring: let io_setup_async_rw take care of iovec Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 07/13] io_uring: don't forget to adjust io_size Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 08/13] io_uring: inline io_read()'s iovec freeing Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 09/13] io_uring: highlight read-retry loop Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 10/13] io_uring: treat NONBLOCK and RWF_NOWAIT similarly Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 11/13] io_uring: io_import_iovec return type cleanup Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 12/13] io_uring: deduplicate file table slot calculation Pavel Begunkov
2021-02-04 13:52 ` [PATCH v2 13/13] io_uring/io-wq: return 2-step work swap scheme Pavel Begunkov
2021-02-04 14:52   ` Jens Axboe
2021-02-04 14:56     ` Pavel Begunkov
2021-02-04 15:05       ` Jens Axboe
2021-02-04 15:07 ` [PATCH v2 5.12 00/13] a second pack of 5.12 cleanups Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=332f7a77b6790ded4df47b28cd9e60ba849b7de3.1612446019.git.asml.silence@gmail.com \
    [email protected] \
    [email protected] \
    [email protected] \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox