From owner-svn-src-stable-10@FreeBSD.ORG Sat Oct 4 19:37:45 2014 Return-Path: Delivered-To: svn-src-stable-10@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 1E6F1B42; Sat, 4 Oct 2014 19:37:45 +0000 (UTC) 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)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 002DBC18; Sat, 4 Oct 2014 19:37:44 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.9/8.14.9) with ESMTP id s94JbiB2032784; Sat, 4 Oct 2014 19:37:44 GMT (envelope-from kib@FreeBSD.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.9/8.14.9/Submit) id s94Jbiq5032783; Sat, 4 Oct 2014 19:37:44 GMT (envelope-from kib@FreeBSD.org) Message-Id: <201410041937.s94Jbiq5032783@svn.freebsd.org> X-Authentication-Warning: svn.freebsd.org: kib set sender to kib@FreeBSD.org using -f From: Konstantin Belousov Date: Sat, 4 Oct 2014 19:37:44 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-10@freebsd.org Subject: svn commit: r272541 - stable/10/sys/kern X-SVN-Group: stable-10 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable-10@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: SVN commit messages for only the 10-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Oct 2014 19:37:45 -0000 Author: kib Date: Sat Oct 4 19:37:44 2014 New Revision: 272541 URL: https://svnweb.freebsd.org/changeset/base/272541 Log: MFC r272130: In kern_linkat() and kern_renameat(), do not call namei(9) while holding a write reference on the filesystem. Try to get write reference in unblocked way after all vnodes are resolved; if failed, drop all locks and retry after waiting for suspension end. Modified: stable/10/sys/kern/vfs_syscalls.c Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/kern/vfs_syscalls.c ============================================================================== --- stable/10/sys/kern/vfs_syscalls.c Sat Oct 4 19:33:58 2014 (r272540) +++ stable/10/sys/kern/vfs_syscalls.c Sat Oct 4 19:37:44 2014 (r272541) @@ -1552,10 +1552,10 @@ kern_linkat(struct thread *td, int fd1, cap_rights_t rights; int error; +again: bwillwrite(); NDINIT_AT(&nd, LOOKUP, follow | AUDITVNODE1, segflg, path1, fd1, td); -again: if ((error = namei(&nd)) != 0) return (error); NDFREE(&nd, NDF_ONLY_PNBUF); @@ -1564,50 +1564,65 @@ again: vrele(vp); return (EPERM); /* POSIX */ } - if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) { - vrele(vp); - return (error); - } NDINIT_ATRIGHTS(&nd, CREATE, LOCKPARENT | SAVENAME | AUDITVNODE2, segflg, path2, fd2, cap_rights_init(&rights, CAP_LINKAT), td); if ((error = namei(&nd)) == 0) { if (nd.ni_vp != NULL) { + NDFREE(&nd, NDF_ONLY_PNBUF); if (nd.ni_dvp == nd.ni_vp) vrele(nd.ni_dvp); else vput(nd.ni_dvp); vrele(nd.ni_vp); - error = EEXIST; - } else if ((error = vn_lock(vp, LK_EXCLUSIVE)) == 0) { + vrele(vp); + return (EEXIST); + } else if (nd.ni_dvp->v_mount != vp->v_mount) { /* - * Check for cross-device links. No need to - * recheck vp->v_type, since it cannot change - * for non-doomed vnode. + * Cross-device link. No need to recheck + * vp->v_type, since it cannot change, except + * to VBAD. */ - if (nd.ni_dvp->v_mount != vp->v_mount) - error = EXDEV; - else - error = can_hardlink(vp, td->td_ucred); - if (error == 0) + NDFREE(&nd, NDF_ONLY_PNBUF); + vput(nd.ni_dvp); + vrele(vp); + return (EXDEV); + } else if ((error = vn_lock(vp, LK_EXCLUSIVE)) == 0) { + error = can_hardlink(vp, td->td_ucred); #ifdef MAC + if (error == 0) error = mac_vnode_check_link(td->td_ucred, nd.ni_dvp, vp, &nd.ni_cnd); - if (error == 0) #endif - error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd); + if (error != 0) { + vput(vp); + vput(nd.ni_dvp); + NDFREE(&nd, NDF_ONLY_PNBUF); + return (error); + } + error = vn_start_write(vp, &mp, V_NOWAIT); + if (error != 0) { + vput(vp); + vput(nd.ni_dvp); + NDFREE(&nd, NDF_ONLY_PNBUF); + error = vn_start_write(NULL, &mp, + V_XSLEEP | PCATCH); + if (error != 0) + return (error); + goto again; + } + error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd); VOP_UNLOCK(vp, 0); vput(nd.ni_dvp); + vn_finished_write(mp); + NDFREE(&nd, NDF_ONLY_PNBUF); } else { vput(nd.ni_dvp); NDFREE(&nd, NDF_ONLY_PNBUF); vrele(vp); - vn_finished_write(mp); goto again; } - NDFREE(&nd, NDF_ONLY_PNBUF); } vrele(vp); - vn_finished_write(mp); return (error); } @@ -3517,6 +3532,7 @@ kern_renameat(struct thread *td, int old cap_rights_t rights; int error; +again: bwillwrite(); #ifdef MAC NDINIT_ATRIGHTS(&fromnd, DELETE, LOCKPARENT | LOCKLEAF | SAVESTART | @@ -3537,14 +3553,6 @@ kern_renameat(struct thread *td, int old VOP_UNLOCK(fromnd.ni_vp, 0); #endif fvp = fromnd.ni_vp; - if (error == 0) - error = vn_start_write(fvp, &mp, V_WAIT | PCATCH); - if (error != 0) { - NDFREE(&fromnd, NDF_ONLY_PNBUF); - vrele(fromnd.ni_dvp); - vrele(fvp); - goto out1; - } NDINIT_ATRIGHTS(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE | SAVESTART | AUDITVNODE2, pathseg, new, newfd, cap_rights_init(&rights, CAP_LINKAT), td); @@ -3557,11 +3565,30 @@ kern_renameat(struct thread *td, int old NDFREE(&fromnd, NDF_ONLY_PNBUF); vrele(fromnd.ni_dvp); vrele(fvp); - vn_finished_write(mp); goto out1; } tdvp = tond.ni_dvp; tvp = tond.ni_vp; + error = vn_start_write(fvp, &mp, V_NOWAIT); + if (error != 0) { + NDFREE(&fromnd, NDF_ONLY_PNBUF); + NDFREE(&tond, NDF_ONLY_PNBUF); + if (tvp != NULL) + vput(tvp); + if (tdvp == tvp) + vrele(tdvp); + else + vput(tdvp); + vrele(fromnd.ni_dvp); + vrele(fvp); + vrele(tond.ni_startdir); + if (fromnd.ni_startdir != NULL) + vrele(fromnd.ni_startdir); + error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH); + if (error != 0) + return (error); + goto again; + } if (tvp != NULL) { if (fvp->v_type == VDIR && tvp->v_type != VDIR) { error = ENOTDIR;