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| author | Stefan Richter <stefanr@s5r6.in-berlin.de> | 2011-07-09 16:42:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-08-04 21:58:34 -0700 |
| commit | 63ab4325d0df2ccefaeb932210d4046f2223e338 (patch) | |
| tree | 5c8d596f73f68c34385222b54e3c7c9747ef6aad /drivers/firewire | |
| parent | 3de8ae6c0d1c0fb73243992adf87c7174028a531 (diff) | |
| download | kernel_samsung_aries-63ab4325d0df2ccefaeb932210d4046f2223e338.zip kernel_samsung_aries-63ab4325d0df2ccefaeb932210d4046f2223e338.tar.gz kernel_samsung_aries-63ab4325d0df2ccefaeb932210d4046f2223e338.tar.bz2 | |
firewire: cdev: return -ENOTTY for unimplemented ioctls, not -EINVAL
commit d873d794235efa590ab3c94d5ee22bb1fab19ac4 upstream.
On Jun 27 Linus Torvalds wrote:
> The correct error code for "I don't understand this ioctl" is ENOTTY.
> The naming may be odd, but you should think of that error value as a
> "unrecognized ioctl number, you're feeding me random numbers that I
> don't understand and I assume for historical reasons that you tried to
> do some tty operation on me".
[...]
> The EINVAL thing goes way back, and is a disaster. It predates Linux
> itself, as far as I can tell. You'll find lots of man-pages that have
> this line in it:
>
> EINVAL Request or argp is not valid.
>
> and it shows up in POSIX etc. And sadly, it generally shows up
> _before_ the line that says
>
> ENOTTY The specified request does not apply to the kind of object
> that the descriptor d references.
>
> so a lot of people get to the EINVAL, and never even notice the ENOTTY.
[...]
> At least glibc (and hopefully other C libraries) use a _string_ that
> makes much more sense: strerror(ENOTTY) is "Inappropriate ioctl for
> device"
So let's correct this in the <linux/firewire-cdev.h> ABI while it is
still young, relative to distributor adoption.
Side note: We return -ENOTTY not only on _IOC_TYPE or _IOC_NR mismatch,
but also on _IOC_SIZE mismatch. An ioctl with an unsupported size of
argument structure can be seen as an unsupported version of that ioctl.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/firewire')
| -rw-r--r-- | drivers/firewire/core-cdev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c index b1c1177..9b5915e 100644 --- a/drivers/firewire/core-cdev.c +++ b/drivers/firewire/core-cdev.c @@ -1583,7 +1583,7 @@ static int dispatch_ioctl(struct client *client, if (_IOC_TYPE(cmd) != '#' || _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers) || _IOC_SIZE(cmd) > sizeof(buffer)) - return -EINVAL; + return -ENOTTY; if (_IOC_DIR(cmd) == _IOC_READ) memset(&buffer, 0, _IOC_SIZE(cmd)); |