Date: Wed, 13 Jul 2016 10:30:32 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r302755 - stable/9/sys/cddl/contrib/opensolaris/uts/common/fs/zfs Message-ID: <201607131030.u6DAUWwO014314@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: avg Date: Wed Jul 13 10:30:32 2016 New Revision: 302755 URL: https://svnweb.freebsd.org/changeset/base/302755 Log: MFC r299947: fix locking in zfsctl_root_lookup Modified: stable/9/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c Directory Properties: stable/9/sys/ (props changed) stable/9/sys/cddl/contrib/opensolaris/ (props changed) Modified: stable/9/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c ============================================================================== --- stable/9/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c Wed Jul 13 10:26:38 2016 (r302754) +++ stable/9/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ctldir.c Wed Jul 13 10:30:32 2016 (r302755) @@ -534,9 +534,20 @@ zfsctl_root_lookup(vnode_t *dvp, char *n ZFS_ENTER(zfsvfs); if (strcmp(nm, "..") == 0) { +#ifdef illumos err = VFS_ROOT(dvp->v_vfsp, LK_EXCLUSIVE, vpp); +#else + /* + * NB: can not use VFS_ROOT here as it would acquire + * the vnode lock of the parent (root) vnode while + * holding the child's (.zfs) lock. + */ + znode_t *rootzp; + + err = zfs_zget(zfsvfs, zfsvfs->z_root, &rootzp); if (err == 0) - VOP_UNLOCK(*vpp, 0); + *vpp = ZTOV(rootzp); +#endif } else { err = gfs_vop_lookup(dvp, nm, vpp, pnp, flags, rdir, cr, ct, direntflags, realpnp); @@ -598,6 +609,7 @@ zfsctl_freebsd_root_lookup(ap) vnode_t **vpp = ap->a_vpp; cred_t *cr = ap->a_cnp->cn_cred; int flags = ap->a_cnp->cn_flags; + int lkflags = ap->a_cnp->cn_lkflags; int nameiop = ap->a_cnp->cn_nameiop; char nm[NAME_MAX + 1]; int err; @@ -609,8 +621,18 @@ zfsctl_freebsd_root_lookup(ap) strlcpy(nm, ap->a_cnp->cn_nameptr, ap->a_cnp->cn_namelen + 1); err = zfsctl_root_lookup(dvp, nm, vpp, NULL, 0, NULL, cr, NULL, NULL, NULL); - if (err == 0 && (nm[0] != '.' || nm[1] != '\0')) - vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY); + if (err == 0 && (nm[0] != '.' || nm[1] != '\0')) { + if (flags & ISDOTDOT) + VOP_UNLOCK(dvp, 0); + err = vn_lock(*vpp, lkflags); + if (err != 0) { + vrele(*vpp); + *vpp = NULL; + } + if (flags & ISDOTDOT) + vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); + } + return (err); }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201607131030.u6DAUWwO014314>