linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jens Axboe <axboe@kernel.dk>
To: majianpeng <majianpeng@gmail.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: Re: For the condition "file->f_mode", when it failed, it should return EACCES rather than EBADF.
Date: Tue, 5 Feb 2013 21:19:03 +0100	[thread overview]
Message-ID: <20130205201903.GY15092@kernel.dk> (raw)
In-Reply-To: <201302052339385271010@gmail.com>

On Tue, Feb 05 2013, majianpeng wrote:
> >On Sun, Feb 03 2013, majianpeng wrote:
> >> Hi all,
> >> 	When I wanted to do discard operations,but i set the  openflag was O_RDONLY,it returned a EBADF rather than EACCES or EPERM.
> >> I searched the code and found:
> >> >case BLKDISCARD:
> >> >case BLKSECDISCARD: {
> >> >		uint64_t range[2];
> >> 
> >> >		if (!(mode & FMODE_WRITE))
> >> >			return -EBADF;
> >> Initial i thought there was error.But i searched all code of kernel and found some places like this.
> >> 
> >> The description of EBADF is "Bad file numbe". There are some places where returned EBADF like,
> >> >if (!f.file)
> >> >		return -EBADF;
> >> 
> >> So i think for checking file->f_mode when failed, it should return EACCESS.
> >
> >But that would break the ABI at this point. I agree with you, though,
> >EBADF is not the right error for this case.
> >
> >-- 
> >Jens Axboe
> >
> Sorry, can you explain in detail? Why can it break the ABI ?

Applications already depending on EBADF being returned for attempt to
discard on a file descriptor not opened for write. Granted it's a slim
possiblity, but it exists.

-- 
Jens Axboe


      reply	other threads:[~2013-02-05 20:20 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-02-04  2:07 For the condition "file->f_mode", when it failed, it should return EACCES rather than EBADF majianpeng
2013-02-05 13:21 ` Jens Axboe
2013-02-05 15:39   ` majianpeng
2013-02-05 20:19     ` Jens Axboe [this message]

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=20130205201903.GY15092@kernel.dk \
    --to=axboe@kernel.dk \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=majianpeng@gmail.com \
    /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;
as well as URLs for NNTP newsgroup(s).