In-Reply-To: <200906151602.42873.arnd@arndb.de>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>, linux-arch@vger.kernel.org,
       linux-arch-owner@vger.kernel.org, linux-kernel@vger.kernel.org,
       liqin.chen@sunplusct.com, Matthew Wilcox <matthew@wil.cx>,
       torvalds@linux-foundation.org
MIME-Version: 1.0
Subject: Re: [PATCH] asm-generic: add EMAXERRNO
Message-ID: <OFD9F2472F.5C67128A-ON482575D7.000F7E83-482575D7.0011466D@sunplusct.com>
From: liqin.chen@sunplusct.com
Date: Tue, 16 Jun 2009 11:04:10 +0800
Content-Type: text/plain; charset="GB2312"
Sender: linux-kernel-owner@vger.kernel.org
Content-Transfer-Encoding: 8bit
Content-Length: 1304
Lines: 33

linux-arch-owner@vger.kernel.org д?? 2009-06-15 22:02:42:

> On Monday 15 June 2009, Matthew Wilcox wrote:
> > On Mon, Jun 15, 2009 at 03:30:09PM +0200, Arnd Bergmann wrote:
> > > Some architectures want to flag error returns from a syscall based 
on
> > > the return value. The range from zero to -511 is for errors that
> > > we can return to user space, so add a #define for this to
> > > include/asm-generic/errno.h.
> > 
> > I thought we could return anything up to -4095.
> 
> Sort of, yes. Internally to the kernel, we use anything up to 4095,
> that's e.g. IS_ERR_VALUE checks for.
> 
> Error numbers from 512 to 4095 are internal and should never be seen
> by the user.
> 
> In reality, it probably does not matter at all because we know what
> error numbers we use. Now that you pointed me to include/linux/err.h,
> that already defines MAX_ERRNO.
> 
> Liqin, I think I'd prefer to just drop my patch again, and you can
> use MAX_ERRNO, which is defined in err.h.
> 
OK.
But I think move MAX_ERRNO define from include/linux/err.h to 
include/asm-generic/errno.h will be more clear. And no harm to
include/linux/err.h file.

liqin
--
????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m????????????I?