[9fans] copying over 9P using plan9port

[9fans] copying over 9P using plan9port

[Jens Staal]

Hi.

First of all sorry if I through my ignorance am attempting something
completely stupid.

I have been trying to copy the APE sources using plan9port. The
purpose of this is that I am trying to make an APE augmentation
PKGBUILD to the kencc package [1] (and ultimately, I will try to
figure out how to make a kencc+APE cross compiler for Plan9 on a Linux
host) for Arch linux.

I have also asked at the Arch forums [2] but no answers yet, so I
guess it is nothing anyone has attempted...

I can mount the sources at bell labs using the following procedure

mkdir sources
9 mount 'tcp!sources.cs.bell-labs.com' sources

I can then cd and explore the bell labs sources via plan9port, so that
works just fine.

When I then try something like

cp -ar sources/plan9/sys/src/ape ape

I get an error stating:
unexpected open flags 0500000cp: can not open
”sources/plan9/sys/src/ape/9src/mkfile” for reading: Access denied

What I now wonder is: Is this the expected behaviour? Is anonymous
copying from the Bell labs sources blocked? Or is the permission
issues local and something I can fix by a mount option? I could not
find anything using 9 man mount...

[1] https://aur.archlinux.org/packages.php?ID=49835
[2] https://bbs.archlinux.org/viewtopic.php?id=127522

Re: [9fans] copying over 9P using plan9port

[David du Colombier]

> What I now wonder is: Is this the expected behaviour?

No. You are doing it fine.
It's working for me right now, authenticated and unauthenticated.

I don't know why it doesn't work for you.
Beware "9 mount" should be spelled "9mount" in your messages.

What kernel version are you using?

--
David du Colombier

Re: [9fans] copying over 9P using plan9port

[Jens Staal]

2011/10/4 David du Colombier <0intro@gmail.com>:
>> What I now wonder is: Is this the expected behaviour?
>
> No. You are doing it fine.
> It's working for me right now, authenticated and unauthenticated.
>
> I don't know why it doesn't work for you.
> Beware "9 mount" should be spelled "9mount" in your messages.
>
> What kernel version are you using?
>
> --
> David du Colombier
>
>

uname -r:
3.0-ARCH

Since you ask about kernel version, I guessed that it meant that it
might be a permission issue on my side. I also tried doing the same
mount and copy as root.
This also failed, so I am confused.

Re: [9fans] copying over 9P using plan9port

[Russ Cox]

What does 'mount' (not 9 mount, just mount)
say after you mount the file system?

That will tell you whether the '9 mount' used
v9fs (Linux 9P driver) or 9pfuse (user-space
9P-to-FUSE translator).

Neither gets much use, so it is easy to believe
that there is a bug.

Russ

Re: [9fans] copying over 9P using plan9port

[Brian L. Stuart]

> I can then cd and explore the bell labs sources via
> plan9port, so that
> works just fine.
> 
> When I then try something like
> 
> cp -ar sources/plan9/sys/src/ape ape
> 
> I get an error stating:
> unexpected open flags 0500000cp: can not open
> ”sources/plan9/sys/src/ape/9src/mkfile” for reading:
> Access denied

Give it a shot without the -a.  I've had a lot of issues
with the strange attribute flags in "modern" Unices.  The
issues have usually been when writing via 9p, but it's
worth a try to see if that has anything to do with it.
Any idea what the 0500000 flags indicate on your system?

BLS

Re: [9fans] copying over 9P using plan9port

[Russ Cox]

To answer my question: the error message comes from 9pfuse.
The extra bits are O_NOFOLLOW and O_LARGEFILE, both of
which seem harmless in this context.  Try this:


diff -r 6db8fc2588f6 src/cmd/9pfuse/main.c
--- a/src/cmd/9pfuse/main.c	Mon Oct 03 18:16:09 2011 -0400
+++ b/src/cmd/9pfuse/main.c	Tue Oct 04 15:43:16 2011 -0400
@@ -577,6 +577,13 @@
 	openmode = flags&3;
 	flags &= ~3;
 	flags &= ~(O_DIRECTORY|O_NONBLOCK|O_LARGEFILE|O_CLOEXEC);
+#ifdef O_NOFOLLOW
+	flags &= ~O_NOFOLLOW
+#endif
+#ifdef O_LARGEFILE
+	flags &= ~O_LARGEFILE
+#endif
+
 	/*
 	 * Discarding O_APPEND here is not completely wrong,
 	 * because the host kernel will rewrite the offsets
@@ -594,7 +601,7 @@
 	 *	O_NONBLOCK -> ONONBLOCK
 	 */
 	if(flags){
-		fprint(2, "unexpected open flags %#uo", (uint)in->flags);
+		fprint(2, "unexpected open flags %#uo\n", (uint)in->flags);
 		replyfuseerrno(m, EACCES);
 		return;
 	}

Re: [9fans] copying over 9P using plan9port

[Jens Staal]

2011/10/4 Russ Cox <rsc@swtch.com>:
> What does 'mount' (not 9 mount, just mount)
> say after you mount the file system?
>
> That will tell you whether the '9 mount' used
> v9fs (Linux 9P driver) or 9pfuse (user-space
> 9P-to-FUSE translator).
>
> Neither gets much use, so it is easy to believe
> that there is a bug.
>
> Russ
>
>

The p9p 9mount uses 9pfuse on my system

Re: [9fans] copying over 9P using plan9port

[Jens Staal]

2011/10/4 Russ Cox <rsc@swtch.com>:
> To answer my question: the error message comes from 9pfuse.
> The extra bits are O_NOFOLLOW and O_LARGEFILE, both of
> which seem harmless in this context.  Try this:
>
>
> diff -r 6db8fc2588f6 src/cmd/9pfuse/main.c
> --- a/src/cmd/9pfuse/main.c     Mon Oct 03 18:16:09 2011 -0400
> +++ b/src/cmd/9pfuse/main.c     Tue Oct 04 15:43:16 2011 -0400
> @@ -577,6 +577,13 @@
>        openmode = flags&3;
>        flags &= ~3;
>        flags &= ~(O_DIRECTORY|O_NONBLOCK|O_LARGEFILE|O_CLOEXEC);
> +#ifdef O_NOFOLLOW
> +       flags &= ~O_NOFOLLOW
> +#endif
> +#ifdef O_LARGEFILE
> +       flags &= ~O_LARGEFILE
> +#endif
> +
>        /*
>         * Discarding O_APPEND here is not completely wrong,
>         * because the host kernel will rewrite the offsets
> @@ -594,7 +601,7 @@
>         *      O_NONBLOCK -> ONONBLOCK
>         */
>        if(flags){
> -               fprint(2, "unexpected open flags %#uo", (uint)in->flags);
> +               fprint(2, "unexpected open flags %#uo\n", (uint)in->flags);
>                replyfuseerrno(m, EACCES);
>                return;
>        }
>
>

Thanks I will try the patch as soon as I got time.

@ brian:

doing "cp -r" instead of "cp -ar" did not make a difference

Re: [9fans] copying over 9P using plan9port

[Nicolas Bercher]

On 04/10/2011 19:08, Jens Staal wrote:
> When I then try something like
>
> cp -ar sources/plan9/sys/src/ape ape
>
> I get an error stating:
> unexpected open flags 0500000cp: can not open
> ”sources/plan9/sys/src/ape/9src/mkfile” for reading: Access denied
>

Hi,

This is working for me without plan9port (Debian GNU/Linux):

   $ mkdir -p /n/sources
   $ mount -t 9p -o proto=tcp 204.178.31.11 /n/sources
   $ cp -ar /n/sources/plan9/sys/src/ape /tmp/ape

Nicolas