From owner-svn-src-all@FreeBSD.ORG Wed Mar 20 17:57:01 2013 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 8E519CA6; Wed, 20 Mar 2013 17:57:01 +0000 (UTC) (envelope-from mckusick@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) by mx1.freebsd.org (Postfix) with ESMTP id 71CE1950; Wed, 20 Mar 2013 17:57:01 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.6/8.14.6) with ESMTP id r2KHv1UQ025134; Wed, 20 Mar 2013 17:57:01 GMT (envelope-from mckusick@svn.freebsd.org) Received: (from mckusick@localhost) by svn.freebsd.org (8.14.6/8.14.5/Submit) id r2KHv0TF025124; Wed, 20 Mar 2013 17:57:00 GMT (envelope-from mckusick@svn.freebsd.org) Message-Id: <201303201757.r2KHv0TF025124@svn.freebsd.org> From: Kirk McKusick Date: Wed, 20 Mar 2013 17:57:00 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r248561 - in head/sys: kern sys ufs/ufs X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Mar 2013 17:57:01 -0000 Author: mckusick Date: Wed Mar 20 17:57:00 2013 New Revision: 248561 URL: http://svnweb.freebsd.org/changeset/base/248561 Log: When renaming a directory from one parent directory to another, we need to call ufs_checkpath() to walk from our new location to the root of the filesystem to ensure that we do not encounter ourselves along the way. Until now, we accomplished this by reading the ".." entries of each directory in our path until we reached the root (or encountered an error). This change tries to avoid the I/O of reading the ".." entries by first looking them up in the name cache and only doing the I/O when the name cache lookup fails. Reviewed by: kib Tested by: Peter Holm MFC after: 4 weeks Modified: head/sys/kern/vfs_cache.c head/sys/sys/vnode.h head/sys/ufs/ufs/ufs_lookup.c Modified: head/sys/kern/vfs_cache.c ============================================================================== --- head/sys/kern/vfs_cache.c Wed Mar 20 16:30:17 2013 (r248560) +++ head/sys/kern/vfs_cache.c Wed Mar 20 17:57:00 2013 (r248561) @@ -1359,6 +1359,28 @@ vn_fullpath1(struct thread *td, struct v return (0); } +struct vnode * +vn_dir_dd_ino(struct vnode *vp) +{ + struct namecache *ncp; + struct vnode *ddvp; + + ASSERT_VOP_LOCKED(vp, "vn_dir_dd_ino"); + CACHE_RLOCK(); + TAILQ_FOREACH(ncp, &(vp->v_cache_dst), nc_dst) { + if ((ncp->nc_flag & NCF_ISDOTDOT) != 0) + continue; + ddvp = ncp->nc_dvp; + VI_LOCK(ddvp); + CACHE_RUNLOCK(); + if (vget(ddvp, LK_INTERLOCK | LK_SHARED | LK_NOWAIT, curthread)) + return (NULL); + return (ddvp); + } + CACHE_RUNLOCK(); + return (NULL); +} + int vn_commname(struct vnode *vp, char *buf, u_int buflen) { Modified: head/sys/sys/vnode.h ============================================================================== --- head/sys/sys/vnode.h Wed Mar 20 16:30:17 2013 (r248560) +++ head/sys/sys/vnode.h Wed Mar 20 17:57:00 2013 (r248561) @@ -622,6 +622,8 @@ int vn_fullpath(struct thread *td, struc char **retbuf, char **freebuf); int vn_fullpath_global(struct thread *td, struct vnode *vn, char **retbuf, char **freebuf); +struct vnode * + vn_dir_dd_ino(struct vnode *vp); int vn_commname(struct vnode *vn, char *buf, u_int buflen); int vn_path_to_global_path(struct thread *td, struct vnode *vp, char *path, u_int pathlen); Modified: head/sys/ufs/ufs/ufs_lookup.c ============================================================================== --- head/sys/ufs/ufs/ufs_lookup.c Wed Mar 20 16:30:17 2013 (r248560) +++ head/sys/ufs/ufs/ufs_lookup.c Wed Mar 20 17:57:00 2013 (r248561) @@ -1387,13 +1387,29 @@ ufs_dirempty(ip, parentino, cred) } static int -ufs_dir_dd_ino(struct vnode *vp, struct ucred *cred, ino_t *dd_ino) +ufs_dir_dd_ino(struct vnode *vp, struct ucred *cred, ino_t *dd_ino, + struct vnode **dd_vp) { struct dirtemplate dirbuf; + struct vnode *ddvp; int error, namlen; + ASSERT_VOP_LOCKED(vp, "ufs_dir_dd_ino"); if (vp->v_type != VDIR) return (ENOTDIR); + /* + * First check to see if we have it in the name cache. + */ + if ((ddvp = vn_dir_dd_ino(vp)) != NULL) { + KASSERT(ddvp->v_mount == vp->v_mount, + ("ufs_dir_dd_ino: Unexpected mount point crossing")); + *dd_ino = VTOI(ddvp)->i_number; + *dd_vp = ddvp; + return (0); + } + /* + * Have to read the directory. + */ error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf, sizeof (struct dirtemplate), (off_t)0, UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, cred, NOCRED, NULL, NULL); @@ -1411,6 +1427,7 @@ ufs_dir_dd_ino(struct vnode *vp, struct dirbuf.dotdot_name[1] != '.') return (ENOTDIR); *dd_ino = dirbuf.dotdot_ino; + *dd_vp = NULL; return (0); } @@ -1435,7 +1452,7 @@ ufs_checkpath(ino_t source_ino, ino_t pa if (target->i_number == ROOTINO) return (0); for (;;) { - error = ufs_dir_dd_ino(vp, cred, &dd_ino); + error = ufs_dir_dd_ino(vp, cred, &dd_ino, &vp1); if (error != 0) break; if (dd_ino == source_ino) { @@ -1446,22 +1463,16 @@ ufs_checkpath(ino_t source_ino, ino_t pa break; if (dd_ino == parent_ino) break; - error = VFS_VGET(mp, dd_ino, LK_SHARED | LK_NOWAIT, &vp1); - if (error != 0) { - *wait_ino = dd_ino; - break; - } - /* Recheck that ".." still points to vp1 after relock of vp */ - error = ufs_dir_dd_ino(vp, cred, &dd_ino); - if (error != 0) { - vput(vp1); - break; - } - /* Redo the check of ".." if directory was reparented */ - if (dd_ino != VTOI(vp1)->i_number) { - vput(vp1); - continue; + if (vp1 == NULL) { + error = VFS_VGET(mp, dd_ino, LK_SHARED | LK_NOWAIT, + &vp1); + if (error != 0) { + *wait_ino = dd_ino; + break; + } } + KASSERT(dd_ino == VTOI(vp1)->i_number, + ("directory %d reparented\n", VTOI(vp1)->i_number)); if (vp != tvp) vput(vp); vp = vp1; @@ -1469,6 +1480,8 @@ ufs_checkpath(ino_t source_ino, ino_t pa if (error == ENOTDIR) panic("checkpath: .. not a directory\n"); + if (vp1 != NULL) + vput(vp1); if (vp != tvp) vput(vp); return (error);