xref: /openbsd/sys/ufs/mfs/mfs_vfsops.c (revision 3d8817e4)
1 /*	$OpenBSD: mfs_vfsops.c,v 1.42 2010/12/21 20:14:44 thib Exp $	*/
2 /*	$NetBSD: mfs_vfsops.c,v 1.10 1996/02/09 22:31:28 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1990, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)mfs_vfsops.c	8.4 (Berkeley) 4/16/94
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/time.h>
38 #include <sys/kernel.h>
39 #include <sys/proc.h>
40 #include <sys/buf.h>
41 #include <sys/mount.h>
42 #include <sys/signalvar.h>
43 #include <sys/vnode.h>
44 #include <sys/malloc.h>
45 #include <sys/kthread.h>
46 
47 #include <ufs/ufs/quota.h>
48 #include <ufs/ufs/inode.h>
49 #include <ufs/ufs/ufsmount.h>
50 #include <ufs/ufs/ufs_extern.h>
51 
52 #include <ufs/ffs/fs.h>
53 #include <ufs/ffs/ffs_extern.h>
54 
55 #include <ufs/mfs/mfsnode.h>
56 #include <ufs/mfs/mfs_extern.h>
57 
58 static	int mfs_minor;	/* used for building internal dev_t */
59 
60 /*
61  * mfs vfs operations.
62  */
63 const struct vfsops mfs_vfsops = {
64 	mfs_mount,
65 	mfs_start,
66 	ffs_unmount,
67 	ufs_root,
68 	ufs_quotactl,
69 	mfs_statfs,
70 	ffs_sync,
71 	ffs_vget,
72 	ffs_fhtovp,
73 	ffs_vptofh,
74 	mfs_init,
75 	ffs_sysctl,
76 	mfs_checkexp
77 };
78 
79 /*
80  * VFS Operations.
81  *
82  * mount system call
83  */
84 /* ARGSUSED */
85 int
86 mfs_mount(struct mount *mp, const char *path, void *data,
87     struct nameidata *ndp, struct proc *p)
88 {
89 	struct vnode *devvp;
90 	struct mfs_args args;
91 	struct ufsmount *ump;
92 	struct fs *fs;
93 	struct mfsnode *mfsp;
94 	size_t size;
95 	int flags, error;
96 
97 	error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args));
98 	if (error)
99 		return (error);
100 
101 	/*
102 	 * If updating, check whether changing from read-only to
103 	 * read/write; if there is no device name, that's all we do.
104 	 */
105 	if (mp->mnt_flag & MNT_UPDATE) {
106 		ump = VFSTOUFS(mp);
107 		fs = ump->um_fs;
108 		if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
109 			flags = WRITECLOSE;
110 			if (mp->mnt_flag & MNT_FORCE)
111 				flags |= FORCECLOSE;
112 			error = ffs_flushfiles(mp, flags, p);
113 			if (error)
114 				return (error);
115 		}
116 		if (fs->fs_ronly && (mp->mnt_flag & MNT_WANTRDWR))
117 			fs->fs_ronly = 0;
118 #ifdef EXPORTMFS
119 		if (args.fspec == 0)
120 			return (vfs_export(mp, &ump->um_export,
121 			    &args.export_info));
122 #endif
123 		return (0);
124 	}
125 	error = getnewvnode(VT_MFS, NULL, &mfs_vops, &devvp);
126 	if (error)
127 		return (error);
128 	devvp->v_type = VBLK;
129 	if (checkalias(devvp, makedev(255, mfs_minor), (struct mount *)0))
130 		panic("mfs_mount: dup dev");
131 	mfs_minor++;
132 	mfsp = malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK);
133 	devvp->v_data = mfsp;
134 	mfsp->mfs_baseoff = args.base;
135 	mfsp->mfs_size = args.size;
136 	mfsp->mfs_vnode = devvp;
137 	mfsp->mfs_pid = p->p_pid;
138 	mfsp->mfs_buflist = (struct buf *)0;
139 	if ((error = ffs_mountfs(devvp, mp, p)) != 0) {
140 		mfsp->mfs_buflist = (struct buf *)-1;
141 		vrele(devvp);
142 		return (error);
143 	}
144 	ump = VFSTOUFS(mp);
145 	fs = ump->um_fs;
146 	(void) copyinstr(path, fs->fs_fsmnt, sizeof(fs->fs_fsmnt) - 1, &size);
147 	bzero(fs->fs_fsmnt + size, sizeof(fs->fs_fsmnt) - size);
148 	bcopy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, MNAMELEN);
149 	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
150 	    &size);
151 	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
152 	bcopy(&args, &mp->mnt_stat.mount_info.mfs_args, sizeof(args));
153 	return (0);
154 }
155 
156 int	mfs_pri = PWAIT | PCATCH;		/* XXX prob. temp */
157 
158 /*
159  * Used to grab the process and keep it in the kernel to service
160  * memory filesystem I/O requests.
161  *
162  * Loop servicing I/O requests.
163  * Copy the requested data into or out of the memory filesystem
164  * address space.
165  */
166 /* ARGSUSED */
167 int
168 mfs_start(struct mount *mp, int flags, struct proc *p)
169 {
170 	struct vnode *vp = VFSTOUFS(mp)->um_devvp;
171 	struct mfsnode *mfsp = VTOMFS(vp);
172 	struct buf *bp;
173 	int sleepreturn = 0, s;
174 
175 	while (1) {
176 		while (1) {
177 			s = splbio();
178 			bp = mfsp->mfs_buflist;
179 			if (bp == NULL || bp == (struct buf *)-1) {
180 				splx(s);
181 				break;
182 			}
183 			mfsp->mfs_buflist = bp->b_actf;
184 			splx(s);
185 			mfs_doio(mfsp, bp);
186 			wakeup((caddr_t)bp);
187 		}
188 		if (bp == (struct buf *)-1)
189 			break;
190 		/*
191 		 * If a non-ignored signal is received, try to unmount.
192 		 * If that fails, clear the signal (it has been "processed"),
193 		 * otherwise we will loop here, as tsleep will always return
194 		 * EINTR/ERESTART.
195 		 */
196 		if (sleepreturn != 0) {
197 			if (vfs_busy(mp, VB_WRITE|VB_NOWAIT) ||
198 			    dounmount(mp,
199 			    (CURSIG(p) == SIGKILL) ? MNT_FORCE : 0, p, NULL))
200 				CLRSIG(p, CURSIG(p));
201 			sleepreturn = 0;
202 			continue;
203 		}
204 		sleepreturn = tsleep((caddr_t)vp, mfs_pri, "mfsidl", 0);
205 	}
206 	return (0);
207 }
208 
209 /*
210  * Get file system statistics.
211  */
212 int
213 mfs_statfs(struct mount *mp, struct statfs *sbp, struct proc *p)
214 {
215 	int error;
216 
217 	error = ffs_statfs(mp, sbp, p);
218 	strncpy(&sbp->f_fstypename[0], mp->mnt_vfc->vfc_name, MFSNAMELEN);
219 	if (sbp != &mp->mnt_stat)
220 		bcopy(&mp->mnt_stat.mount_info.mfs_args,
221 		    &sbp->mount_info.mfs_args, sizeof(struct mfs_args));
222 	return (error);
223 }
224 
225 /*
226  * check export permission, not supported
227  */
228 /* ARGUSED */
229 int
230 mfs_checkexp(struct mount *mp, struct mbuf *nam, int *exflagsp,
231     struct ucred **credanonp)
232 {
233 	return (EOPNOTSUPP);
234 }
235 
236 /*
237  * Memory based filesystem initialization.
238  */
239 int
240 mfs_init(struct vfsconf *vfsp)
241 {
242 	return (ffs_init(vfsp));
243 }
244