Annotation of src/sys/miscfs/nullfs/null_vfsops.c, Revision 1.85
1.85 ! hannken 1: /* $NetBSD: null_vfsops.c,v 1.84 2012/04/30 22:51:27 rmind Exp $ */
1.2 cgd 2:
1.1 mycroft 3: /*
1.24 wrstuden 4: * Copyright (c) 1999 National Aeronautics & Space Administration
5: * All rights reserved.
6: *
7: * This software was written by William Studenmund of the
1.30 wiz 8: * Numerical Aerospace Simulation Facility, NASA Ames Research Center.
1.24 wrstuden 9: *
10: * Redistribution and use in source and binary forms, with or without
11: * modification, are permitted provided that the following conditions
12: * are met:
13: * 1. Redistributions of source code must retain the above copyright
14: * notice, this list of conditions and the following disclaimer.
15: * 2. Redistributions in binary form must reproduce the above copyright
16: * notice, this list of conditions and the following disclaimer in the
17: * documentation and/or other materials provided with the distribution.
1.25 soren 18: * 3. Neither the name of the National Aeronautics & Space Administration
1.24 wrstuden 19: * nor the names of its contributors may be used to endorse or promote
20: * products derived from this software without specific prior written
21: * permission.
22: *
23: * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION
24: * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25: * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26: * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB-
27: * UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
28: * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33: * POSSIBILITY OF SUCH DAMAGE.
34: */
1.82 rmind 35:
1.24 wrstuden 36: /*
1.19 fvdl 37: * Copyright (c) 1992, 1993, 1995
1.1 mycroft 38: * The Regents of the University of California. All rights reserved.
39: *
40: * This code is derived from software donated to Berkeley by
41: * Jan-Simon Pendry.
42: *
43: * Redistribution and use in source and binary forms, with or without
44: * modification, are permitted provided that the following conditions
45: * are met:
46: * 1. Redistributions of source code must retain the above copyright
47: * notice, this list of conditions and the following disclaimer.
48: * 2. Redistributions in binary form must reproduce the above copyright
49: * notice, this list of conditions and the following disclaimer in the
50: * documentation and/or other materials provided with the distribution.
1.43 agc 51: * 3. Neither the name of the University nor the names of its contributors
1.1 mycroft 52: * may be used to endorse or promote products derived from this software
53: * without specific prior written permission.
54: *
55: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
56: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
59: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65: * SUCH DAMAGE.
66: *
67: * from: Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp
68: * from: @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92
1.19 fvdl 69: * @(#)null_vfsops.c 8.7 (Berkeley) 5/14/95
1.1 mycroft 70: */
71:
72: /*
1.82 rmind 73: * Null file-system: VFS operations.
74: *
75: * See null_vnops.c for a description.
1.1 mycroft 76: */
1.36 lukem 77:
78: #include <sys/cdefs.h>
1.85 ! hannken 79: __KERNEL_RCSID(0, "$NetBSD: null_vfsops.c,v 1.84 2012/04/30 22:51:27 rmind Exp $");
1.1 mycroft 80:
81: #include <sys/param.h>
82: #include <sys/systm.h>
1.44 atatat 83: #include <sys/sysctl.h>
1.1 mycroft 84: #include <sys/vnode.h>
85: #include <sys/mount.h>
86: #include <sys/namei.h>
87: #include <sys/malloc.h>
1.76 rumble 88: #include <sys/module.h>
1.33 enami 89:
1.1 mycroft 90: #include <miscfs/nullfs/null.h>
1.24 wrstuden 91: #include <miscfs/genfs/layer_extern.h>
1.1 mycroft 92:
1.80 jld 93: MODULE(MODULE_CLASS_VFS, null, "layerfs");
1.76 rumble 94:
1.68 pooka 95: VFS_PROTOS(nullfs);
1.24 wrstuden 96:
1.77 ad 97: static struct sysctllog *nullfs_sysctl_log;
98:
1.1 mycroft 99: int
1.79 dsl 100: nullfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len)
1.1 mycroft 101: {
1.82 rmind 102: struct vnode *lowerrootvp, *vp;
1.65 dsl 103: struct null_args *args = data;
1.24 wrstuden 104: struct null_mount *nmp;
105: struct layer_mount *lmp;
1.83 dholland 106: struct pathbuf *pb;
1.82 rmind 107: struct nameidata nd;
108: int error;
1.1 mycroft 109:
1.82 rmind 110: if (*data_len < sizeof(*args))
1.65 dsl 111: return EINVAL;
112:
1.38 christos 113: if (mp->mnt_flag & MNT_GETARGS) {
114: lmp = MOUNTTOLAYERMOUNT(mp);
115: if (lmp == NULL)
116: return EIO;
1.65 dsl 117: args->la.target = NULL;
1.82 rmind 118: *data_len = sizeof(*args);
1.65 dsl 119: return 0;
1.38 christos 120: }
1.1 mycroft 121:
1.82 rmind 122: /* Update is not supported. */
1.57 jmmv 123: if (mp->mnt_flag & MNT_UPDATE)
124: return EOPNOTSUPP;
1.24 wrstuden 125:
1.82 rmind 126: /* Find the lower vnode and lock it. */
1.83 dholland 127: error = pathbuf_copyin(args->la.target, &pb);
128: if (error) {
129: return error;
130: }
131: NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF, pb);
1.82 rmind 132: if ((error = namei(&nd)) != 0) {
1.83 dholland 133: pathbuf_destroy(pb);
1.82 rmind 134: return error;
135: }
1.68 pooka 136: lowerrootvp = nd.ni_vp;
1.83 dholland 137: pathbuf_destroy(pb);
1.1 mycroft 138:
1.82 rmind 139: /* Create the mount point. */
1.84 rmind 140: nmp = kmem_zalloc(sizeof(struct null_mount), KM_SLEEP);
1.37 soren 141: mp->mnt_data = nmp;
1.24 wrstuden 142: nmp->nullm_vfs = lowerrootvp->v_mount;
143: if (nmp->nullm_vfs->mnt_flag & MNT_LOCAL)
144: mp->mnt_flag |= MNT_LOCAL;
1.1 mycroft 145:
146: /*
1.24 wrstuden 147: * Make sure that the mount point is sufficiently initialized
148: * that the node create call will work.
1.1 mycroft 149: */
1.27 assar 150: vfs_getnewfsid(mp);
1.24 wrstuden 151:
1.33 enami 152: nmp->nullm_size = sizeof(struct null_node);
1.24 wrstuden 153: nmp->nullm_tag = VT_NULL;
154: nmp->nullm_bypass = layer_bypass;
155: nmp->nullm_alloc = layer_node_alloc; /* the default alloc is fine */
156: nmp->nullm_vnodeop_p = null_vnodeop_p;
1.69 ad 157: mutex_init(&nmp->nullm_hashlock, MUTEX_DEFAULT, IPL_NONE);
1.75 ad 158: nmp->nullm_node_hashtbl = hashinit(desiredvnodes, HASH_LIST, true,
159: &nmp->nullm_node_hash);
1.1 mycroft 160:
1.82 rmind 161: /* Setup a null node for root vnode. */
1.85 ! hannken 162: VOP_UNLOCK(lowerrootvp);
1.24 wrstuden 163: error = layer_node_create(mp, lowerrootvp, &vp);
1.1 mycroft 164: if (error) {
1.85 ! hannken 165: vrele(lowerrootvp);
1.75 ad 166: hashdone(nmp->nullm_node_hashtbl, HASH_LIST,
167: nmp->nullm_node_hash);
1.84 rmind 168: kmem_free(nmp, sizeof(struct null_mount));
1.82 rmind 169: return error;
1.1 mycroft 170: }
1.21 wrstuden 171: /*
1.82 rmind 172: * Keep a held reference to the root vnode. It will be released on
173: * umount. Note: nullfs is MP-safe.
1.21 wrstuden 174: */
1.85 ! hannken 175: vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1.69 ad 176: vp->v_vflag |= VV_ROOT;
1.72 ad 177: nmp->nullm_rootvp = vp;
178: mp->mnt_iflag |= IMNT_MPSAFE;
1.81 hannken 179: VOP_UNLOCK(vp);
1.1 mycroft 180:
1.65 dsl 181: error = set_statvfs_info(path, UIO_USERSPACE, args->la.target,
1.82 rmind 182: UIO_USERSPACE, mp->mnt_op->vfs_name, mp, curlwp);
1.54 perry 183: return error;
1.1 mycroft 184: }
185:
186: int
1.70 pooka 187: nullfs_unmount(struct mount *mp, int mntflags)
1.1 mycroft 188: {
1.34 enami 189: struct null_mount *nmp = MOUNTTONULLMOUNT(mp);
190: struct vnode *null_rootvp = nmp->nullm_rootvp;
1.82 rmind 191: int error, flags = 0;
1.1 mycroft 192:
1.19 fvdl 193: if (mntflags & MNT_FORCE)
1.1 mycroft 194: flags |= FORCECLOSE;
195:
1.64 pooka 196: if (null_rootvp->v_usecount > 1 && (mntflags & MNT_FORCE) == 0)
1.82 rmind 197: return EBUSY;
198:
1.24 wrstuden 199: if ((error = vflush(mp, null_rootvp, flags)) != 0)
1.82 rmind 200: return error;
1.1 mycroft 201:
1.82 rmind 202: /* Eliminate all activity and release the vnode. */
1.24 wrstuden 203: vgone(null_rootvp);
1.33 enami 204:
1.82 rmind 205: /* Finally, destroy the mount point structures. */
1.75 ad 206: hashdone(nmp->nullm_node_hashtbl, HASH_LIST, nmp->nullm_node_hash);
1.69 ad 207: mutex_destroy(&nmp->nullm_hashlock);
1.84 rmind 208: kmem_free(mp->mnt_data, sizeof(struct null_mount));
1.33 enami 209: mp->mnt_data = NULL;
1.82 rmind 210: return 0;
1.1 mycroft 211: }
212:
1.29 jdolecek 213: extern const struct vnodeopv_desc null_vnodeop_opv_desc;
1.18 thorpej 214:
1.29 jdolecek 215: const struct vnodeopv_desc * const nullfs_vnodeopv_descs[] = {
1.19 fvdl 216: &null_vnodeop_opv_desc,
1.18 thorpej 217: NULL,
218: };
219:
1.17 thorpej 220: struct vfsops nullfs_vfsops = {
1.1 mycroft 221: MOUNT_NULL,
1.65 dsl 222: sizeof (struct null_args),
1.1 mycroft 223: nullfs_mount,
1.24 wrstuden 224: layerfs_start,
1.1 mycroft 225: nullfs_unmount,
1.24 wrstuden 226: layerfs_root,
227: layerfs_quotactl,
1.47 christos 228: layerfs_statvfs,
1.24 wrstuden 229: layerfs_sync,
230: layerfs_vget,
231: layerfs_fhtovp,
232: layerfs_vptofh,
233: layerfs_init,
1.32 chs 234: NULL,
1.26 jdolecek 235: layerfs_done,
1.18 thorpej 236: NULL, /* vfs_mountroot */
1.51 wrstuden 237: layerfs_snapshot,
1.53 thorpej 238: vfs_stdextattrctl,
1.67 pooka 239: (void *)eopnotsupp, /* vfs_suspendctl */
1.73 dholland 240: layerfs_renamelock_enter,
241: layerfs_renamelock_exit,
1.74 ad 242: (void *)eopnotsupp,
1.18 thorpej 243: nullfs_vnodeopv_descs,
1.59 christos 244: 0,
245: { NULL, NULL },
1.1 mycroft 246: };
1.76 rumble 247:
248: static int
1.80 jld 249: null_modcmd(modcmd_t cmd, void *arg)
1.76 rumble 250: {
1.77 ad 251: int error;
1.76 rumble 252:
253: switch (cmd) {
254: case MODULE_CMD_INIT:
1.77 ad 255: error = vfs_attach(&nullfs_vfsops);
256: if (error != 0)
257: break;
258: sysctl_createv(&nullfs_sysctl_log, 0, NULL, NULL,
259: CTLFLAG_PERMANENT,
260: CTLTYPE_NODE, "vfs", NULL,
261: NULL, 0, NULL, 0,
262: CTL_VFS, CTL_EOL);
263: sysctl_createv(&nullfs_sysctl_log, 0, NULL, NULL,
264: CTLFLAG_PERMANENT,
265: CTLTYPE_NODE, "null",
266: SYSCTL_DESCR("Loopback file system"),
267: NULL, 0, NULL, 0,
268: CTL_VFS, 9, CTL_EOL);
269: /*
270: * XXX the "9" above could be dynamic, thereby eliminating
271: * one more instance of the "number to vfs" mapping problem,
272: * but "9" is the order as taken from sys/mount.h
273: */
274: break;
1.76 rumble 275: case MODULE_CMD_FINI:
1.77 ad 276: error = vfs_detach(&nullfs_vfsops);
277: if (error != 0)
278: break;
279: sysctl_teardown(&nullfs_sysctl_log);
280: break;
1.76 rumble 281: default:
1.77 ad 282: error = ENOTTY;
283: break;
1.76 rumble 284: }
1.77 ad 285: return error;
1.76 rumble 286: }
CVSweb <webmaster@jp.NetBSD.org>
![[BACK]](/icons/back.gif){kind=icon}
Return to null_vfsops.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [cvs.NetBSD.org] / src / sys / miscfs / nullfs