xref: /dragonfly/sys/vfs/autofs/autofs_vfsops.c (revision eca362d0)
1 /*-
2  * Copyright (c) 2016 The DragonFly Project
3  * Copyright (c) 2014 The FreeBSD Foundation
4  * All rights reserved.
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/stat.h>
35 
36 #include "autofs.h"
37 #include "autofs_mount.h"
38 
39 static int	autofs_statfs(struct mount *mp, struct statfs *sbp,
40 		    struct ucred *cred);
41 
42 extern struct autofs_softc	*autofs_softc;
43 
44 static int
45 autofs_mount(struct mount *mp, char *mntpt, caddr_t data, struct ucred *cred)
46 {
47 	struct autofs_mount_info info;
48 	struct autofs_mount *amp;
49 	struct statfs *sbp = &mp->mnt_stat;
50 	int error;
51 
52 	if (mp->mnt_flag & MNT_UPDATE) {
53 		autofs_flush(VFSTOAUTOFS(mp));
54 		return (0);
55 	}
56 
57 	error = copyin(data, &info, sizeof(info));
58 	if (error)
59 		return (error);
60 
61 	/*
62 	 * Copy-in ->f_mntfromname string.
63 	 */
64 	memset(sbp->f_mntfromname, 0, sizeof(sbp->f_mntfromname));
65 	error = copyinstr(info.from, sbp->f_mntfromname,
66 	    sizeof(sbp->f_mntfromname), NULL);
67 	if (error)
68 		return (error);
69 	/*
70 	 * Copy-in ->f_mntonname string.
71 	 */
72 	memset(sbp->f_mntonname, 0, sizeof(sbp->f_mntonname));
73 	error = copyinstr(mntpt, sbp->f_mntonname,
74 	    sizeof(sbp->f_mntonname), NULL);
75 	if (error)
76 		return (error);
77 
78 	/*
79 	 * Allocate the autofs mount.
80 	 */
81 	amp = kmalloc(sizeof(*amp), M_AUTOFS, M_WAITOK | M_ZERO);
82 	mp->mnt_data = (qaddr_t)amp;
83 	amp->am_mp = mp;
84 	strlcpy(amp->am_from, sbp->f_mntfromname, sizeof(amp->am_from));
85 	strlcpy(amp->am_on, sbp->f_mntonname, sizeof(amp->am_on));
86 
87 	/*
88 	 * Copy-in master_options string.
89 	 */
90 	error = copyinstr(info.master_options, amp->am_options,
91 	    sizeof(amp->am_options), NULL);
92 	if (error)
93 		goto fail;
94 	/*
95 	 * Copy-in master_prefix string.
96 	 */
97 	error = copyinstr(info.master_prefix, amp->am_prefix,
98 	    sizeof(amp->am_prefix), NULL);
99 	if (error)
100 		goto fail;
101 
102 	/*
103 	 * Initialize the autofs mount.
104 	 */
105 	lockinit(&amp->am_lock, "autofsmnlk", 0, 0);
106 	amp->am_last_ino = AUTOFS_ROOTINO;
107 
108 	vfs_getnewfsid(mp);
109 	vfs_add_vnodeops(mp, &autofs_vnode_vops, &mp->mnt_vn_norm_ops);
110 
111 	lockmgr(&amp->am_lock, LK_EXCLUSIVE);
112 	error = autofs_node_new(NULL, amp, ".", -1, &amp->am_root);
113 	lockmgr(&amp->am_lock, LK_RELEASE);
114 	KKASSERT(error == 0);
115 	KKASSERT(amp->am_root->an_ino == AUTOFS_ROOTINO);
116 
117 	autofs_statfs(mp, sbp, cred);
118 
119 	return (0);
120 
121 fail:
122 	kfree(amp, M_AUTOFS);
123 	return (error);
124 }
125 
126 static int
127 autofs_unmount(struct mount *mp, int mntflags)
128 {
129 	struct autofs_mount *amp = VFSTOAUTOFS(mp);
130 	struct autofs_node *anp;
131 	struct autofs_request *ar;
132 	int error, flags, dummy;
133 	bool found;
134 
135 	flags = 0;
136 	if (mntflags & MNT_FORCE)
137 		flags |= FORCECLOSE;
138 	error = vflush(mp, 0, flags);
139 	if (error) {
140 		AUTOFS_WARN("vflush failed with error %d", error);
141 		return (error);
142 	}
143 
144 	/*
145 	 * All vnodes are gone, and new one will not appear - so,
146 	 * no new triggerings.
147 	 */
148 	for (;;) {
149 		found = false;
150 		lockmgr(&autofs_softc->sc_lock, LK_EXCLUSIVE);
151 		TAILQ_FOREACH(ar, &autofs_softc->sc_requests, ar_next) {
152 			if (ar->ar_mount != amp)
153 				continue;
154 			ar->ar_error = ENXIO;
155 			ar->ar_done = true;
156 			ar->ar_in_progress = false;
157 			found = true;
158 		}
159 		if (found == false) {
160 			lockmgr(&autofs_softc->sc_lock, LK_RELEASE);
161 			break;
162 		}
163 
164 		cv_broadcast(&autofs_softc->sc_cv);
165 		lockmgr(&autofs_softc->sc_lock, LK_RELEASE);
166 
167 		tsleep(&dummy, 0, "autofs_umount", hz);
168 	}
169 
170 	lockmgr(&amp->am_lock, LK_EXCLUSIVE);
171 	while (!RB_EMPTY(&amp->am_root->an_children)) {
172 		anp = RB_MIN(autofs_node_tree, &amp->am_root->an_children);
173 		if (!RB_EMPTY(&anp->an_children)) {
174 			AUTOFS_DEBUG("%s has children", anp->an_name);
175 			lockmgr(&amp->am_lock, LK_RELEASE);
176 			return EBUSY;
177 		}
178 		autofs_node_delete(anp);
179 	}
180 	autofs_node_delete(amp->am_root);
181 	mp->mnt_data = NULL;
182 	lockmgr(&amp->am_lock, LK_RELEASE);
183 
184 	lockuninit(&amp->am_lock);
185 
186 	kfree(amp, M_AUTOFS);
187 
188 	return (0);
189 }
190 
191 static int
192 autofs_root(struct mount *mp, struct vnode **vpp)
193 {
194 	struct autofs_mount *amp = VFSTOAUTOFS(mp);
195 	int error;
196 
197 	if (amp->am_root == NULL) {
198 		AUTOFS_FATAL("called without root node %p", mp);
199 		print_backtrace(-1);
200 		*vpp = NULL;
201 		error = EINVAL;
202 	} else {
203 		error = autofs_node_vn(amp->am_root, mp, LK_EXCLUSIVE, vpp);
204 		(*vpp)->v_flag |= VROOT;
205 		KKASSERT((*vpp)->v_type == VDIR);
206 	}
207 
208 	return (error);
209 }
210 
211 static int
212 autofs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
213 {
214 	sbp->f_bsize = S_BLKSIZE;
215 	sbp->f_iosize = 0;
216 	sbp->f_blocks = 0;
217 	sbp->f_bfree = 0;
218 	sbp->f_bavail = 0;
219 	sbp->f_files = 0;
220 	sbp->f_ffree = 0;
221 
222 	return (0);
223 }
224 
225 static int
226 autofs_statvfs(struct mount *mp, struct statvfs *sbp, struct ucred *cred)
227 {
228 	sbp->f_bsize = S_BLKSIZE;
229 	sbp->f_frsize = 0;
230 	sbp->f_blocks = 0;
231 	sbp->f_bfree = 0;
232 	sbp->f_bavail = 0;
233 	sbp->f_files = 0;
234 	sbp->f_ffree = 0;
235 
236 	return (0);
237 }
238 
239 static struct vfsops autofs_vfsops = {
240 	.vfs_mount =		autofs_mount,
241 	.vfs_unmount =		autofs_unmount,
242 	.vfs_root =		autofs_root,
243 	.vfs_statfs =		autofs_statfs,
244 	.vfs_statvfs =		autofs_statvfs,
245 	.vfs_init =		autofs_init,
246 	.vfs_uninit =		autofs_uninit,
247 #if 0
248 	.vfs_vptofh =		NULL,
249 	.vfs_fhtovp =		NULL,
250 	.vfs_checkexp =		NULL,
251 #endif
252 };
253 
254 VFS_SET(autofs_vfsops, autofs, VFCF_SYNTHETIC | VFCF_NETWORK);
255 MODULE_VERSION(autofs, 1);
256