From owner-svn-src-head@FreeBSD.ORG Mon Aug 5 18:54:00 2013 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 88FAAA93; Mon, 5 Aug 2013 18:54:00 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 674F32077; Mon, 5 Aug 2013 18:54:00 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id r75Is0Cb090984; Mon, 5 Aug 2013 18:54:00 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.7/8.14.5/Submit) id r75Is09Q090977; Mon, 5 Aug 2013 18:54:00 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <201308051854.r75Is09Q090977@svn.freebsd.org> From: Konstantin Belousov Date: Mon, 5 Aug 2013 18:54:00 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r253967 - head/sys/fs/tmpfs X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 05 Aug 2013 18:54:00 -0000 Author: kib Date: Mon Aug 5 18:53:59 2013 New Revision: 253967 URL: http://svnweb.freebsd.org/changeset/base/253967 Log: The tmpfs_alloc_vp() is used to instantiate vnode for the tmpfs node, in particular, from the tmpfs_lookup VOP method. If LK_NOWAIT is not specified in the lkflags, the lookup is supposed to return an alive vnode whenever the underlying node is valid. Currently, the tmpfs_alloc_vp() returns ENOENT if the vnode attached to node exists and is being reclaimed. This causes spurious ENOENT errors from lookup on tmpfs and corresponding random 'No such file' failures from syscalls working with tmpfs files. Fix this by waiting for the doomed vnode to be detached from the tmpfs node if sleepable allocation is requested. Note that filesystems which use vfs_hash.c, correctly handle the case due to vfs_hash_get() looping when vget() returns ENOENT for sleepable requests. Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 2 weeks Modified: head/sys/fs/tmpfs/tmpfs.h head/sys/fs/tmpfs/tmpfs_subr.c Modified: head/sys/fs/tmpfs/tmpfs.h ============================================================================== --- head/sys/fs/tmpfs/tmpfs.h Mon Aug 5 18:11:02 2013 (r253966) +++ head/sys/fs/tmpfs/tmpfs.h Mon Aug 5 18:53:59 2013 (r253967) @@ -307,6 +307,7 @@ LIST_HEAD(tmpfs_node_list, tmpfs_node); #define TMPFS_VNODE_ALLOCATING 1 #define TMPFS_VNODE_WANT 2 #define TMPFS_VNODE_DOOMED 4 +#define TMPFS_VNODE_WRECLAIM 8 /* --------------------------------------------------------------------- */ /* Modified: head/sys/fs/tmpfs/tmpfs_subr.c ============================================================================== --- head/sys/fs/tmpfs/tmpfs_subr.c Mon Aug 5 18:11:02 2013 (r253966) +++ head/sys/fs/tmpfs/tmpfs_subr.c Mon Aug 5 18:53:59 2013 (r253967) @@ -479,11 +479,32 @@ tmpfs_alloc_vp(struct mount *mp, struct error = 0; loop: TMPFS_NODE_LOCK(node); +loop1: if ((vp = node->tn_vnode) != NULL) { MPASS((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0); VI_LOCK(vp); + if ((node->tn_type == VDIR && node->tn_dir.tn_parent == NULL) || + ((vp->v_iflag & VI_DOOMED) != 0 && + (lkflag & LK_NOWAIT) != 0)) { + VI_UNLOCK(vp); + TMPFS_NODE_UNLOCK(node); + error = ENOENT; + vp = NULL; + goto out; + } + if ((vp->v_iflag & VI_DOOMED) != 0) { + VI_UNLOCK(vp); + node->tn_vpstate |= TMPFS_VNODE_WRECLAIM; + while ((node->tn_vpstate & TMPFS_VNODE_WRECLAIM) != 0) { + msleep(&node->tn_vnode, TMPFS_NODE_MTX(node), + 0, "tmpfsE", 0); + } + goto loop1; + } TMPFS_NODE_UNLOCK(node); error = vget(vp, lkflag | LK_INTERLOCK, curthread); + if (error == ENOENT) + goto loop; if (error != 0) { vp = NULL; goto out; @@ -620,6 +641,9 @@ tmpfs_free_vp(struct vnode *vp) mtx_assert(TMPFS_NODE_MTX(node), MA_OWNED); node->tn_vnode = NULL; + if ((node->tn_vpstate & TMPFS_VNODE_WRECLAIM) != 0) + wakeup(&node->tn_vnode); + node->tn_vpstate &= ~TMPFS_VNODE_WRECLAIM; vp->v_data = NULL; }