[Qemu-devel] [PATCH] Return EOPNOTSUPP instead of ENOSYS for *xattr* syscalls

[Qemu-devel] [PATCH] Return EOPNOTSUPP instead of ENOSYS for *xattr* syscalls

[Arnaud Patard]

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In current code, we're sending ENOSYS to target when a syscall for the
xattrs is done. This makes applications like ls complain loudly about
that and breaks scripts parsing the output. Moreover, iirc, implemented
features of filesystems are are sending EOPNOTSUPP (I've not checked so
I may be a little bit wrong on that...).
So, I'm proposing to return -EOPNOTSUPP and make ls happy.

As a side not, I'd like to know if there's a reason for not having
implemented the *xattr* syscalls support. If someone has a clue, please
share it :).


Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
---

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diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index ec04170..a036dd4 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -6279,7 +6279,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
     case TARGET_NR_removexattr:
     case TARGET_NR_lremovexattr:
     case TARGET_NR_fremovexattr:
-        goto unimplemented_nowarn;
+         ret = -TARGET_EOPNOTSUPP;
+	 break;
 #endif
 #ifdef TARGET_NR_set_thread_area
     case TARGET_NR_set_thread_area:

Re: [Qemu-devel] [PATCH] Return EOPNOTSUPP instead of ENOSYS for *xattr* syscalls

[François Revol]

>
> In current code, we're sending ENOSYS to target when a syscall for
> the
> xattrs is done. This makes applications like ls complain loudly about
> that and breaks scripts parsing the output. Moreover, iirc,
> implemented
> features of filesystems are are sending EOPNOTSUPP (I've not checked
> so
> I may be a little bit wrong on that...).
> So, I'm proposing to return -EOPNOTSUPP and make ls happy.
>
> As a side not, I'd like to know if there's a reason for not having
> implemented the *xattr* syscalls support. If someone has a clue,
> please
> share it :).

Possibly to avoid endianness issues with binary data ?

François.

Re: [Qemu-devel] [PATCH] Return EOPNOTSUPP instead of ENOSYS for *xattr* syscalls

[Riku Voipio]

On Tue, Apr 21, 2009 at 10:32:09AM +0200, Arnaud Patard wrote:
> In current code, we're sending ENOSYS to target when a syscall for the
> xattrs is done. This makes applications like ls complain loudly about
> that and breaks scripts parsing the output. Moreover, iirc, implemented
> features of filesystems are are sending EOPNOTSUPP (I've not checked so
> I may be a little bit wrong on that...).
> So, I'm proposing to return -EOPNOTSUPP and make ls happy.

Looks ok to me.

Acked-By: Riku Voipio <riku.voipio@iki.fi>

> As a side not, I'd like to know if there's a reason for not having
> implemented the *xattr* syscalls support. If someone has a clue, please
> share it :).

I guess nobody has just needed extended attributes and linux-user qemu
so far.

> ---

> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index ec04170..a036dd4 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -6279,7 +6279,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
>      case TARGET_NR_removexattr:
>      case TARGET_NR_lremovexattr:
>      case TARGET_NR_fremovexattr:
> -        goto unimplemented_nowarn;
> +         ret = -TARGET_EOPNOTSUPP;
> +	 break;
>  #endif
>  #ifdef TARGET_NR_set_thread_area
>      case TARGET_NR_set_thread_area: