xref: /netbsd/sys/ufs/mfs/mfs_vfsops.c (revision bf9ec67e)
1 /*	$NetBSD: mfs_vfsops.c,v 1.38 2002/03/04 02:25:24 simonb Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1990, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)mfs_vfsops.c	8.11 (Berkeley) 6/19/95
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: mfs_vfsops.c,v 1.38 2002/03/04 02:25:24 simonb Exp $");
40 
41 #if defined(_KERNEL_OPT)
42 #include "opt_compat_netbsd.h"
43 #endif
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/time.h>
48 #include <sys/kernel.h>
49 #include <sys/proc.h>
50 #include <sys/buf.h>
51 #include <sys/mount.h>
52 #include <sys/signalvar.h>
53 #include <sys/vnode.h>
54 #include <sys/malloc.h>
55 
56 #include <miscfs/syncfs/syncfs.h>
57 
58 #include <ufs/ufs/quota.h>
59 #include <ufs/ufs/inode.h>
60 #include <ufs/ufs/ufsmount.h>
61 #include <ufs/ufs/ufs_extern.h>
62 
63 #include <ufs/ffs/fs.h>
64 #include <ufs/ffs/ffs_extern.h>
65 
66 #include <ufs/mfs/mfsnode.h>
67 #include <ufs/mfs/mfs_extern.h>
68 
69 caddr_t	mfs_rootbase;	/* address of mini-root in kernel virtual memory */
70 u_long	mfs_rootsize;	/* size of mini-root in bytes */
71 
72 static	int mfs_minor;	/* used for building internal dev_t */
73 
74 extern int (**mfs_vnodeop_p) __P((void *));
75 
76 /*
77  * mfs vfs operations.
78  */
79 
80 extern const struct vnodeopv_desc mfs_vnodeop_opv_desc;
81 
82 const struct vnodeopv_desc * const mfs_vnodeopv_descs[] = {
83 	&mfs_vnodeop_opv_desc,
84 	NULL,
85 };
86 
87 struct vfsops mfs_vfsops = {
88 	MOUNT_MFS,
89 	mfs_mount,
90 	mfs_start,
91 	ffs_unmount,
92 	ufs_root,
93 	ufs_quotactl,
94 	mfs_statfs,
95 	ffs_sync,
96 	ffs_vget,
97 	ffs_fhtovp,
98 	ffs_vptofh,
99 	mfs_init,
100 	mfs_reinit,
101 	mfs_done,
102 	ffs_sysctl,
103 	NULL,
104 	ufs_check_export,
105 	mfs_vnodeopv_descs,
106 };
107 
108 /*
109  * Memory based filesystem initialization.
110  */
111 void
112 mfs_init()
113 {
114 	/*
115 	 * ffs_init() ensures to initialize necessary resources
116 	 * only once.
117 	 */
118 	ffs_init();
119 }
120 
121 void
122 mfs_reinit()
123 {
124 	ffs_reinit();
125 }
126 
127 void
128 mfs_done()
129 {
130 	/*
131 	 * ffs_done() ensures to free necessary resources
132 	 * only once, when it's no more needed.
133 	 */
134 	ffs_done();
135 }
136 
137 /*
138  * Called by main() when mfs is going to be mounted as root.
139  */
140 
141 int
142 mfs_mountroot()
143 {
144 	struct fs *fs;
145 	struct mount *mp;
146 	struct proc *p = curproc;	/* XXX */
147 	struct ufsmount *ump;
148 	struct mfsnode *mfsp;
149 	int error = 0;
150 
151 	/*
152 	 * Get vnodes for rootdev.
153 	 */
154 	if (bdevvp(rootdev, &rootvp)) {
155 		printf("mfs_mountroot: can't setup bdevvp's");
156 		return (error);
157 	}
158 
159 	if ((error = vfs_rootmountalloc(MOUNT_MFS, "mfs_root", &mp))) {
160 		vrele(rootvp);
161 		return (error);
162 	}
163 
164 	mfsp = malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK);
165 	rootvp->v_data = mfsp;
166 	rootvp->v_op = mfs_vnodeop_p;
167 	rootvp->v_tag = VT_MFS;
168 	mfsp->mfs_baseoff = mfs_rootbase;
169 	mfsp->mfs_size = mfs_rootsize;
170 	mfsp->mfs_vnode = rootvp;
171 	mfsp->mfs_proc = NULL;		/* indicate kernel space */
172 	BUFQ_INIT(&mfsp->mfs_buflist);
173 	if ((error = ffs_mountfs(rootvp, mp, p)) != 0) {
174 		mp->mnt_op->vfs_refcount--;
175 		vfs_unbusy(mp);
176 		free(mp, M_MOUNT);
177 		free(mfsp, M_MFSNODE);
178 		vrele(rootvp);
179 		return (error);
180 	}
181 	simple_lock(&mountlist_slock);
182 	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
183 	simple_unlock(&mountlist_slock);
184 	mp->mnt_vnodecovered = NULLVP;
185 	ump = VFSTOUFS(mp);
186 	fs = ump->um_fs;
187 	(void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0);
188 	(void)ffs_statfs(mp, &mp->mnt_stat, p);
189 	vfs_unbusy(mp);
190 	inittodr((time_t)0);
191 	return (0);
192 }
193 
194 /*
195  * This is called early in boot to set the base address and size
196  * of the mini-root.
197  */
198 int
199 mfs_initminiroot(base)
200 	caddr_t base;
201 {
202 	struct fs *fs = (struct fs *)(base + SBOFF);
203 
204 	/* check for valid super block */
205 	if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
206 	    fs->fs_bsize < sizeof(struct fs))
207 		return (0);
208 	mountroot = mfs_mountroot;
209 	mfs_rootbase = base;
210 	mfs_rootsize = fs->fs_fsize * fs->fs_size;
211 	rootdev = makedev(255, mfs_minor);
212 	mfs_minor++;
213 	return (mfs_rootsize);
214 }
215 
216 /*
217  * VFS Operations.
218  *
219  * mount system call
220  */
221 /* ARGSUSED */
222 int
223 mfs_mount(mp, path, data, ndp, p)
224 	struct mount *mp;
225 	const char *path;
226 	void *data;
227 	struct nameidata *ndp;
228 	struct proc *p;
229 {
230 	struct vnode *devvp;
231 	struct mfs_args args;
232 	struct ufsmount *ump;
233 	struct fs *fs;
234 	struct mfsnode *mfsp;
235 	size_t size;
236 	int flags, error;
237 
238 	/*
239 	 * XXX turn off async to avoid hangs when writing lots of data.
240 	 * the problem is that MFS needs to allocate pages to clean pages,
241 	 * so if we wait until the last minute to clean pages then there
242 	 * may not be any pages available to do the cleaning.
243 	 */
244 	mp->mnt_flag &= ~MNT_ASYNC;
245 
246 	error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args));
247 	if (error)
248 		return (error);
249 
250 	/*
251 	 * If updating, check whether changing from read-only to
252 	 * read/write; if there is no device name, that's all we do.
253 	 */
254 	if (mp->mnt_flag & MNT_UPDATE) {
255 		ump = VFSTOUFS(mp);
256 		fs = ump->um_fs;
257 		if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
258 			flags = WRITECLOSE;
259 			if (mp->mnt_flag & MNT_FORCE)
260 				flags |= FORCECLOSE;
261 			error = ffs_flushfiles(mp, flags, p);
262 			if (error)
263 				return (error);
264 		}
265 		if (fs->fs_ronly && (mp->mnt_flag & MNT_WANTRDWR))
266 			fs->fs_ronly = 0;
267 		if (args.fspec == 0)
268 			return (vfs_export(mp, &ump->um_export, &args.export));
269 		return (0);
270 	}
271 	error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp);
272 	if (error)
273 		return (error);
274 	devvp->v_type = VBLK;
275 	if (checkalias(devvp, makedev(255, mfs_minor), (struct mount *)0))
276 		panic("mfs_mount: dup dev");
277 	mfs_minor++;
278 	mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK);
279 	devvp->v_data = mfsp;
280 	mfsp->mfs_baseoff = args.base;
281 	mfsp->mfs_size = args.size;
282 	mfsp->mfs_vnode = devvp;
283 	mfsp->mfs_proc = p;
284 	BUFQ_INIT(&mfsp->mfs_buflist);
285 	if ((error = ffs_mountfs(devvp, mp, p)) != 0) {
286 		BUFQ_FIRST(&mfsp->mfs_buflist) = (struct buf *) -1;
287 		vrele(devvp);
288 		return (error);
289 	}
290 	ump = VFSTOUFS(mp);
291 	fs = ump->um_fs;
292 	(void) copyinstr(path, fs->fs_fsmnt, sizeof(fs->fs_fsmnt) - 1, &size);
293 	memset(fs->fs_fsmnt + size, 0, sizeof(fs->fs_fsmnt) - size);
294 	memcpy(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN);
295 	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
296 	    &size);
297 	memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size);
298 	return (0);
299 }
300 
301 int	mfs_pri = PWAIT | PCATCH;		/* XXX prob. temp */
302 
303 /*
304  * Used to grab the process and keep it in the kernel to service
305  * memory filesystem I/O requests.
306  *
307  * Loop servicing I/O requests.
308  * Copy the requested data into or out of the memory filesystem
309  * address space.
310  */
311 /* ARGSUSED */
312 int
313 mfs_start(mp, flags, p)
314 	struct mount *mp;
315 	int flags;
316 	struct proc *p;
317 {
318 	struct vnode *vp = VFSTOUFS(mp)->um_devvp;
319 	struct mfsnode *mfsp = VTOMFS(vp);
320 	struct buf *bp;
321 	caddr_t base;
322 	int sleepreturn = 0;
323 
324 	base = mfsp->mfs_baseoff;
325 	while (BUFQ_FIRST(&mfsp->mfs_buflist) != (struct buf *) -1) {
326 		while ((bp = BUFQ_FIRST(&mfsp->mfs_buflist)) != NULL) {
327 			BUFQ_REMOVE(&mfsp->mfs_buflist, bp);
328 			mfs_doio(bp, base);
329 			wakeup((caddr_t)bp);
330 		}
331 		/*
332 		 * If a non-ignored signal is received, try to unmount.
333 		 * If that fails, or the filesystem is already in the
334 		 * process of being unmounted, clear the signal (it has been
335 		 * "processed"), otherwise we will loop here, as tsleep
336 		 * will always return EINTR/ERESTART.
337 		 */
338 		if (sleepreturn != 0) {
339 			/*
340 			 * XXX Freeze syncer.  Must do this before locking
341 			 * the mount point.  See dounmount() for details.
342 			 */
343 			lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL);
344 			if (vfs_busy(mp, LK_NOWAIT, 0) != 0)
345 				lockmgr(&syncer_lock, LK_RELEASE, NULL);
346 			else if (dounmount(mp, 0, p) != 0)
347 				CLRSIG(p, CURSIG(p));
348 			sleepreturn = 0;
349 			continue;
350 		}
351 
352 		sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0);
353 	}
354 	return (sleepreturn);
355 }
356 
357 /*
358  * Get file system statistics.
359  */
360 int
361 mfs_statfs(mp, sbp, p)
362 	struct mount *mp;
363 	struct statfs *sbp;
364 	struct proc *p;
365 {
366 	int error;
367 
368 	error = ffs_statfs(mp, sbp, p);
369 #ifdef COMPAT_09
370 	sbp->f_type = 3;
371 #else
372 	sbp->f_type = 0;
373 #endif
374 	strncpy(&sbp->f_fstypename[0], mp->mnt_op->vfs_name, MFSNAMELEN);
375 	return (error);
376 }
377