2006-08-28 13:28:53

by Yi Yang

Subject: [2.6.18-rc* PATCH RFC]: Correct ambiguous errno of aio

In the current implementation of AIO, for the operation IOCB_CMD_FDSYNC
and IOCB_CMD_FSYNC, the returned errno is -EINVAL although the kernel
does know them, I think the correct errno should be -EOPNOTSUPP which
means they aren't be implemented or supported.

>From the kernel source code, we can see they can be supported without
any code modification if a specific filesystem implements aio_fsync.

Another obvious problem is the function aio_fsync is as same as the
function aio_fdsync, so they are duplicate, only one is enough.

Here this patch is.



--- a/fs/aio.c.orig 2006-08-28 15:15:18.000000000 +0800
+++ b/fs/aio.c 2006-08-28 15:33:59.000000000 +0800
@@ -1363,20 +1363,10 @@ static ssize_t aio_pwrite(struct kiocb *
return ret;
}

-static ssize_t aio_fdsync(struct kiocb *iocb)
-{
- struct file *file = iocb->ki_filp;
- ssize_t ret = -EINVAL;
-
- if (file->f_op->aio_fsync)
- ret = file->f_op->aio_fsync(iocb, 1);
- return ret;
-}
-
static ssize_t aio_fsync(struct kiocb *iocb)
{
struct file *file = iocb->ki_filp;
- ssize_t ret = -EINVAL;
+ ssize_t ret = -EOPNOTSUPP;

if (file->f_op->aio_fsync)
ret = file->f_op->aio_fsync(iocb, 0);
@@ -1425,12 +1415,12 @@ static ssize_t aio_setup_iocb(struct kio
kiocb->ki_retry = aio_pwrite;
break;
case IOCB_CMD_FDSYNC:
- ret = -EINVAL;
+ ret = -EOPNOTSUPP;
if (file->f_op->aio_fsync)
- kiocb->ki_retry = aio_fdsync;
+ kiocb->ki_retry = aio_fsync;
break;
case IOCB_CMD_FSYNC:
- ret = -EINVAL;
+ ret = -EOPNOTSUPP;
if (file->f_op->aio_fsync)
kiocb->ki_retry = aio_fsync;
break;

2006-08-28 14:08:27

by Frederik Deweerdt

Subject: Re: [2.6.18-rc* PATCH RFC]: Correct ambiguous errno of aio

On Mon, Aug 28, 2006 at 09:28:48PM +0800, Yi Yang wrote:
> In the current implementation of AIO, for the operation IOCB_CMD_FDSYNC
> and IOCB_CMD_FSYNC, the returned errno is -EINVAL although the kernel
> does know them, I think the correct errno should be -EOPNOTSUPP which
> means they aren't be implemented or supported.
Hi,

If I'm not mistaken, returning EINVAL conforms to POSIX, isn't it?
http://www.opengroup.org/onlinepubs/009695399/functions/fsync.html
Regards,
Frederik

2006-08-28 14:55:46

by Yi Yang

Subject: Re: [2.6.18-rc* PATCH RFC]: Correct ambiguous errno of aio

Frederik Deweerdt 写道:
> On Mon, Aug 28, 2006 at 09:28:48PM +0800, Yi Yang wrote:
>
>> In the current implementation of AIO, for the operation IOCB_CMD_FDSYNC
>> and IOCB_CMD_FSYNC, the returned errno is -EINVAL although the kernel
>> does know them, I think the correct errno should be -EOPNOTSUPP which
>> means they aren't be implemented or supported.
>>
> Hi,
>
> If I'm not mistaken, returning EINVAL conforms to POSIX, isn't it?
>
But POSIX also defined ENOTSUP which is equal to EOPNOTSUPP for linux.
> http://www.opengroup.org/onlinepubs/009695399/functions/fsync.html
> Regards,
> Frederik
>
>
>

2006-08-28 15:39:32

by Randy Dunlap

Subject: Re: [2.6.18-rc* PATCH RFC]: Correct ambiguous errno of aio

On Mon, 28 Aug 2006 21:28:48 +0800 Yi Yang wrote:

> In the current implementation of AIO, for the operation IOCB_CMD_FDSYNC
> and IOCB_CMD_FSYNC, the returned errno is -EINVAL although the kernel
> does know them, I think the correct errno should be -EOPNOTSUPP which
> means they aren't be implemented or supported.
>
> >From the kernel source code, we can see they can be supported without
> any code modification if a specific filesystem implements aio_fsync.
>
> Another obvious problem is the function aio_fsync is as same as the
> function aio_fdsync, so they are duplicate, only one is enough.
>
> Here this patch is.
>
gmail ate all of the tabs, maybe other whitespace problems.

>
> --- a/fs/aio.c.orig 2006-08-28 15:15:18.000000000 +0800
> +++ b/fs/aio.c 2006-08-28 15:33:59.000000000 +0800
> @@ -1363,20 +1363,10 @@ static ssize_t aio_pwrite(struct kiocb *
> return ret;
> }
>
> -static ssize_t aio_fdsync(struct kiocb *iocb)
> -{
> - struct file *file = iocb->ki_filp;
> - ssize_t ret = -EINVAL;
> -
> - if (file->f_op->aio_fsync)
> - ret = file->f_op->aio_fsync(iocb, 1);
> - return ret;
> -}
> -
> static ssize_t aio_fsync(struct kiocb *iocb)
> {
> struct file *file = iocb->ki_filp;
> - ssize_t ret = -EINVAL;
> + ssize_t ret = -EOPNOTSUPP;
>
> if (file->f_op->aio_fsync)
> ret = file->f_op->aio_fsync(iocb, 0);
> @@ -1425,12 +1415,12 @@ static ssize_t aio_setup_iocb(struct kio
> kiocb->ki_retry = aio_pwrite;
> break;
> case IOCB_CMD_FDSYNC:
> - ret = -EINVAL;
> + ret = -EOPNOTSUPP;
> if (file->f_op->aio_fsync)
> - kiocb->ki_retry = aio_fdsync;
> + kiocb->ki_retry = aio_fsync;
> break;
> case IOCB_CMD_FSYNC:
> - ret = -EINVAL;
> + ret = -EOPNOTSUPP;
> if (file->f_op->aio_fsync)
> kiocb->ki_retry = aio_fsync;
> break;
> -

---
~Randy