/* $NetBSD: genfs_vnops.c,v 1.167 2008/04/28 20:24:08 martin Exp $ */ /*- * Copyright (c) 2008 The NetBSD Foundation, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * */ #include __KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.167 2008/04/28 20:24:08 martin Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static void filt_genfsdetach(struct knote *); static int filt_genfsread(struct knote *, long); static int filt_genfsvnode(struct knote *, long); int genfs_poll(void *v) { struct vop_poll_args /* { struct vnode *a_vp; int a_events; struct lwp *a_l; } */ *ap = v; return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM)); } int genfs_seek(void *v) { struct vop_seek_args /* { struct vnode *a_vp; off_t a_oldoff; off_t a_newoff; kauth_cred_t cred; } */ *ap = v; if (ap->a_newoff < 0) return (EINVAL); return (0); } int genfs_abortop(void *v) { struct vop_abortop_args /* { struct vnode *a_dvp; struct componentname *a_cnp; } */ *ap = v; if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF) PNBUF_PUT(ap->a_cnp->cn_pnbuf); return (0); } int genfs_fcntl(void *v) { struct vop_fcntl_args /* { struct vnode *a_vp; u_int a_command; void *a_data; int a_fflag; kauth_cred_t a_cred; struct lwp *a_l; } */ *ap = v; if (ap->a_command == F_SETFL) return (0); else return (EOPNOTSUPP); } /*ARGSUSED*/ int genfs_badop(void *v) { panic("genfs: bad op"); } /*ARGSUSED*/ int genfs_nullop(void *v) { return (0); } /*ARGSUSED*/ int genfs_einval(void *v) { return (EINVAL); } /* * Called when an fs doesn't support a particular vop. * This takes care to vrele, vput, or vunlock passed in vnodes. */ int genfs_eopnotsupp(void *v) { struct vop_generic_args /* struct vnodeop_desc *a_desc; / * other random data follows, presumably * / } */ *ap = v; struct vnodeop_desc *desc = ap->a_desc; struct vnode *vp, *vp_last = NULL; int flags, i, j, offset; flags = desc->vdesc_flags; for (i = 0; i < VDESC_MAX_VPS; flags >>=1, i++) { if ((offset = desc->vdesc_vp_offsets[i]) == VDESC_NO_OFFSET) break; /* stop at end of list */ if ((j = flags & VDESC_VP0_WILLPUT)) { vp = *VOPARG_OFFSETTO(struct vnode **, offset, ap); /* Skip if NULL */ if (!vp) continue; switch (j) { case VDESC_VP0_WILLPUT: /* Check for dvp == vp cases */ if (vp == vp_last) vrele(vp); else { vput(vp); vp_last = vp; } break; case VDESC_VP0_WILLUNLOCK: VOP_UNLOCK(vp, 0); break; case VDESC_VP0_WILLRELE: vrele(vp); break; } } } return (EOPNOTSUPP); } /*ARGSUSED*/ int genfs_ebadf(void *v) { return (EBADF); } /* ARGSUSED */ int genfs_enoioctl(void *v) { return (EPASSTHROUGH); } /* * Eliminate all activity associated with the requested vnode * and with all vnodes aliased to the requested vnode. */ int genfs_revoke(void *v) { struct vop_revoke_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; #ifdef DIAGNOSTIC if ((ap->a_flags & REVOKEALL) == 0) panic("genfs_revoke: not revokeall"); #endif vrevoke(ap->a_vp); return (0); } /* * Lock the node. */ int genfs_lock(void *v) { struct vop_lock_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; int flags = ap->a_flags; if ((flags & LK_INTERLOCK) != 0) { flags &= ~LK_INTERLOCK; mutex_exit(&vp->v_interlock); } return (vlockmgr(vp->v_vnlock, flags)); } /* * Unlock the node. */ int genfs_unlock(void *v) { struct vop_unlock_args /* { struct vnode *a_vp; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; KASSERT(ap->a_flags == 0); return (vlockmgr(vp->v_vnlock, LK_RELEASE)); } /* * Return whether or not the node is locked. */ int genfs_islocked(void *v) { struct vop_islocked_args /* { struct vnode *a_vp; } */ *ap = v; struct vnode *vp = ap->a_vp; return (vlockstatus(vp->v_vnlock)); } /* * Stubs to use when there is no locking to be done on the underlying object. */ int genfs_nolock(void *v) { struct vop_lock_args /* { struct vnode *a_vp; int a_flags; struct lwp *a_l; } */ *ap = v; /* * Since we are not using the lock manager, we must clear * the interlock here. */ if (ap->a_flags & LK_INTERLOCK) mutex_exit(&ap->a_vp->v_interlock); return (0); } int genfs_nounlock(void *v) { return (0); } int genfs_noislocked(void *v) { return (0); } int genfs_mmap(void *v) { return (0); } void genfs_node_init(struct vnode *vp, const struct genfs_ops *ops) { struct genfs_node *gp = VTOG(vp); rw_init(&gp->g_glock); gp->g_op = ops; } void genfs_node_destroy(struct vnode *vp) { struct genfs_node *gp = VTOG(vp); rw_destroy(&gp->g_glock); } void genfs_size(struct vnode *vp, off_t size, off_t *eobp, int flags) { int bsize; bsize = 1 << vp->v_mount->mnt_fs_bshift; *eobp = (size + bsize - 1) & ~(bsize - 1); } static void filt_genfsdetach(struct knote *kn) { struct vnode *vp = (struct vnode *)kn->kn_hook; mutex_enter(&vp->v_interlock); SLIST_REMOVE(&vp->v_klist, kn, knote, kn_selnext); mutex_exit(&vp->v_interlock); } static int filt_genfsread(struct knote *kn, long hint) { struct vnode *vp = (struct vnode *)kn->kn_hook; int rv; /* * filesystem is gone, so set the EOF flag and schedule * the knote for deletion. */ switch (hint) { case NOTE_REVOKE: KASSERT(mutex_owned(&vp->v_interlock)); kn->kn_flags |= (EV_EOF | EV_ONESHOT); return (1); case 0: mutex_enter(&vp->v_interlock); kn->kn_data = vp->v_size - ((file_t *)kn->kn_obj)->f_offset; rv = (kn->kn_data != 0); mutex_exit(&vp->v_interlock); return rv; default: KASSERT(mutex_owned(&vp->v_interlock)); kn->kn_data = vp->v_size - ((file_t *)kn->kn_obj)->f_offset; return (kn->kn_data != 0); } } static int filt_genfsvnode(struct knote *kn, long hint) { struct vnode *vp = (struct vnode *)kn->kn_hook; int fflags; switch (hint) { case NOTE_REVOKE: KASSERT(mutex_owned(&vp->v_interlock)); kn->kn_flags |= EV_EOF; if ((kn->kn_sfflags & hint) != 0) kn->kn_fflags |= hint; return (1); case 0: mutex_enter(&vp->v_interlock); fflags = kn->kn_fflags; mutex_exit(&vp->v_interlock); break; default: KASSERT(mutex_owned(&vp->v_interlock)); if ((kn->kn_sfflags & hint) != 0) kn->kn_fflags |= hint; fflags = kn->kn_fflags; break; } return (fflags != 0); } static const struct filterops genfsread_filtops = { 1, NULL, filt_genfsdetach, filt_genfsread }; static const struct filterops genfsvnode_filtops = { 1, NULL, filt_genfsdetach, filt_genfsvnode }; int genfs_kqfilter(void *v) { struct vop_kqfilter_args /* { struct vnode *a_vp; struct knote *a_kn; } */ *ap = v; struct vnode *vp; struct knote *kn; vp = ap->a_vp; kn = ap->a_kn; switch (kn->kn_filter) { case EVFILT_READ: kn->kn_fop = &genfsread_filtops; break; case EVFILT_VNODE: kn->kn_fop = &genfsvnode_filtops; break; default: return (EINVAL); } kn->kn_hook = vp; mutex_enter(&vp->v_interlock); SLIST_INSERT_HEAD(&vp->v_klist, kn, kn_selnext); mutex_exit(&vp->v_interlock); return (0); } void genfs_node_wrlock(struct vnode *vp) { struct genfs_node *gp = VTOG(vp); rw_enter(&gp->g_glock, RW_WRITER); } void genfs_node_rdlock(struct vnode *vp) { struct genfs_node *gp = VTOG(vp); rw_enter(&gp->g_glock, RW_READER); } void genfs_node_unlock(struct vnode *vp) { struct genfs_node *gp = VTOG(vp); rw_exit(&gp->g_glock); }