From owner-freebsd-emulation@FreeBSD.ORG Thu Jan 6 10:40:59 2011 Return-Path: Delivered-To: freebsd-emulation@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C13AA106564A for ; Thu, 6 Jan 2011 10:40:59 +0000 (UTC) (envelope-from Andre.Albsmeier@siemens.com) Received: from goliath.siemens.de (goliath.siemens.de [192.35.17.28]) by mx1.freebsd.org (Postfix) with ESMTP id 5680B8FC18 for ; Thu, 6 Jan 2011 10:40:59 +0000 (UTC) Received: from mail2.siemens.de (localhost [127.0.0.1]) by goliath.siemens.de (8.12.11.20060308/8.12.11) with ESMTP id p06AewPL009934; Thu, 6 Jan 2011 11:40:58 +0100 Received: from curry.mchp.siemens.de (curry.mchp.siemens.de [139.25.40.130]) by mail2.siemens.de (8.13.6/8.13.6) with ESMTP id p06Aev6X031673; Thu, 6 Jan 2011 11:40:58 +0100 Received: (from localhost) by curry.mchp.siemens.de (8.14.4/8.14.4) id p06Aev2K093680; Date: Thu, 6 Jan 2011 11:40:57 +0100 From: Andre Albsmeier To: Alexander Leidinger Message-ID: <20110106104057.GB59969@curry.mchp.siemens.de> References: <20101230075124.GA12923@curry.mchp.siemens.de> <20101231144800.00005c6d@unknown> <20110101224629.GA30540@curry.mchp.siemens.de> <20110102115021.00000c8b@unknown> <20110105191915.GA43997@curry.mchp.siemens.de> <20110106090130.20784sf1w9verdic@webmail.leidinger.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110106090130.20784sf1w9verdic@webmail.leidinger.net> X-Echelon: X-Advice: Drop that crappy M$-Outlook, I'm tired of your viruses! User-Agent: Mutt/1.5.20 (2009-06-14) Cc: "freebsd-emulation@freebsd.org" Subject: Re: 7.3-STABLE and Linux version of SIMetrix X-BeenThere: freebsd-emulation@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Development of Emulators of other operating systems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Jan 2011 10:40:59 -0000 On Thu, 06-Jan-2011 at 09:01:30 +0100, Alexander Leidinger wrote: > Quoting Andre Albsmeier (from Wed, 5 Jan > 2011 20:19:15 +0100): > > > Got it running... A short explanation: > > > > Linux' shm_open() fails because it wants to find some funky shmfs > > to construct the full pathname. It starts to search at the default > > mountpoint which is /dev/shm. If this fails it runs through fstab > > and searches for shmfs and tmpfs. Whatever it finds will be > > statfs()'ed to be checked for Linux' fs magic for shmfs (0x01021994). > > What does it expect as a filesystem type if it does not find shmfs in > fstab but tmpfs? If it does not find tmpfs, will it try /tmp anyway > (but check for some fstype magic)? It searches for every mount which is of type tmpfs or shm. Whatever it finds must have the fs magic SHMFS_SUPER_MAGIC (0x01021994). It's in sysdeps/unix/sysv/linux/shm_open.c: ------------------------- snip ------------------- /* Now read the entries. */ while ((mp = __getmntent_r (fp, &resmem, buf, sizeof buf)) != NULL) /* The original name is "shm" but this got changed in early Linux 2.4.x to "tmpfs". */ if (strcmp (mp->mnt_type, "tmpfs") == 0 #ifndef __ASSUME_TMPFS_NAME || strcmp (mp->mnt_type, "shm") == 0 #endif ) { /* Found it. There might be more than one place where the filesystem is mounted but one is enough for us. */ size_t namelen; /* First make sure this really is the correct entry. At least some versions of the kernel give wrong information because of the implicit mount of the shmfs for SysV IPC. */ if (__statfs (mp->mnt_dir, &f) != 0 || f.f_type != SHMFS_SUPER_MAGIC) continue; ------------------------- snap ------------------- -Andre > > Bye, > Alexander. > > -- > Money cannot buy love, nor even friendship. > > http://www.Leidinger.net Alexander @ Leidinger.net: PGP ID = B0063FE7 > http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID = 72077137 > -- FreeBSD: We eat penguins for breakfast