xref: /netbsd/sys/ufs/mfs/mfs_vfsops.c (revision c4a72b64)
1 /*	$NetBSD: mfs_vfsops.c,v 1.42 2002/10/24 16:41:00 chs 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 1.42 2002/10/24 16:41:00 chs 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 	mfsp->mfs_shutdown = 0;
173 	bufq_alloc(&mfsp->mfs_buflist, BUFQ_FCFS);
174 	if ((error = ffs_mountfs(rootvp, mp, p)) != 0) {
175 		mp->mnt_op->vfs_refcount--;
176 		vfs_unbusy(mp);
177 		bufq_free(&mfsp->mfs_buflist);
178 		free(mp, M_MOUNT);
179 		free(mfsp, M_MFSNODE);
180 		vrele(rootvp);
181 		return (error);
182 	}
183 	simple_lock(&mountlist_slock);
184 	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
185 	simple_unlock(&mountlist_slock);
186 	mp->mnt_vnodecovered = NULLVP;
187 	ump = VFSTOUFS(mp);
188 	fs = ump->um_fs;
189 	(void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0);
190 	(void)ffs_statfs(mp, &mp->mnt_stat, p);
191 	vfs_unbusy(mp);
192 	inittodr((time_t)0);
193 	return (0);
194 }
195 
196 /*
197  * This is called early in boot to set the base address and size
198  * of the mini-root.
199  */
200 int
201 mfs_initminiroot(base)
202 	caddr_t base;
203 {
204 	struct fs *fs = (struct fs *)(base + SBOFF);
205 
206 	/* check for valid super block */
207 	if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
208 	    fs->fs_bsize < sizeof(struct fs))
209 		return (0);
210 	mountroot = mfs_mountroot;
211 	mfs_rootbase = base;
212 	mfs_rootsize = fs->fs_fsize * fs->fs_size;
213 	rootdev = makedev(255, mfs_minor);
214 	mfs_minor++;
215 	return (mfs_rootsize);
216 }
217 
218 /*
219  * VFS Operations.
220  *
221  * mount system call
222  */
223 /* ARGSUSED */
224 int
225 mfs_mount(mp, path, data, ndp, p)
226 	struct mount *mp;
227 	const char *path;
228 	void *data;
229 	struct nameidata *ndp;
230 	struct proc *p;
231 {
232 	struct vnode *devvp;
233 	struct mfs_args args;
234 	struct ufsmount *ump;
235 	struct fs *fs;
236 	struct mfsnode *mfsp;
237 	size_t size;
238 	int flags, error;
239 
240 	if (mp->mnt_flag & MNT_GETARGS) {
241 		struct vnode *vp;
242 		struct mfsnode *mfsp;
243 
244 		ump = VFSTOUFS(mp);
245 		if (ump == NULL)
246 			return EIO;
247 
248 		vp = ump->um_devvp;
249 		if (vp == NULL)
250 			return EIO;
251 
252 		mfsp = VTOMFS(vp);
253 		if (mfsp == NULL)
254 			return EIO;
255 
256 		args.fspec = NULL;
257 		vfs_showexport(mp, &args.export, &ump->um_export);
258 		args.base = mfsp->mfs_baseoff;
259 		args.size = mfsp->mfs_size;
260 		return copyout(&args, data, sizeof(args));
261 	}
262 	/*
263 	 * XXX turn off async to avoid hangs when writing lots of data.
264 	 * the problem is that MFS needs to allocate pages to clean pages,
265 	 * so if we wait until the last minute to clean pages then there
266 	 * may not be any pages available to do the cleaning.
267 	 * ... and since the default partially-synchronous mode turns out
268 	 * to not be sufficient under heavy load, make it full synchronous.
269 	 */
270 	mp->mnt_flag &= ~MNT_ASYNC;
271 	mp->mnt_flag |= MNT_SYNCHRONOUS;
272 
273 	error = copyin(data, (caddr_t)&args, sizeof (struct mfs_args));
274 	if (error)
275 		return (error);
276 
277 	/*
278 	 * If updating, check whether changing from read-only to
279 	 * read/write; if there is no device name, that's all we do.
280 	 */
281 	if (mp->mnt_flag & MNT_UPDATE) {
282 		ump = VFSTOUFS(mp);
283 		fs = ump->um_fs;
284 		if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
285 			flags = WRITECLOSE;
286 			if (mp->mnt_flag & MNT_FORCE)
287 				flags |= FORCECLOSE;
288 			error = ffs_flushfiles(mp, flags, p);
289 			if (error)
290 				return (error);
291 		}
292 		if (fs->fs_ronly && (mp->mnt_flag & MNT_WANTRDWR))
293 			fs->fs_ronly = 0;
294 		if (args.fspec == 0)
295 			return (vfs_export(mp, &ump->um_export, &args.export));
296 		return (0);
297 	}
298 	error = getnewvnode(VT_MFS, (struct mount *)0, mfs_vnodeop_p, &devvp);
299 	if (error)
300 		return (error);
301 	devvp->v_type = VBLK;
302 	if (checkalias(devvp, makedev(255, mfs_minor), (struct mount *)0))
303 		panic("mfs_mount: dup dev");
304 	mfs_minor++;
305 	mfsp = (struct mfsnode *)malloc(sizeof *mfsp, M_MFSNODE, M_WAITOK);
306 	devvp->v_data = mfsp;
307 	mfsp->mfs_baseoff = args.base;
308 	mfsp->mfs_size = args.size;
309 	mfsp->mfs_vnode = devvp;
310 	mfsp->mfs_proc = p;
311 	mfsp->mfs_shutdown = 0;
312 	bufq_alloc(&mfsp->mfs_buflist, BUFQ_FCFS);
313 	if ((error = ffs_mountfs(devvp, mp, p)) != 0) {
314 		mfsp->mfs_shutdown = 1;
315 		vrele(devvp);
316 		return (error);
317 	}
318 	ump = VFSTOUFS(mp);
319 	fs = ump->um_fs;
320 	(void) copyinstr(path, fs->fs_fsmnt, sizeof(fs->fs_fsmnt) - 1, &size);
321 	memset(fs->fs_fsmnt + size, 0, sizeof(fs->fs_fsmnt) - size);
322 	memcpy(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN);
323 	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
324 	    &size);
325 	memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size);
326 	return (0);
327 }
328 
329 int	mfs_pri = PWAIT | PCATCH;		/* XXX prob. temp */
330 
331 /*
332  * Used to grab the process and keep it in the kernel to service
333  * memory filesystem I/O requests.
334  *
335  * Loop servicing I/O requests.
336  * Copy the requested data into or out of the memory filesystem
337  * address space.
338  */
339 /* ARGSUSED */
340 int
341 mfs_start(mp, flags, p)
342 	struct mount *mp;
343 	int flags;
344 	struct proc *p;
345 {
346 	struct vnode *vp = VFSTOUFS(mp)->um_devvp;
347 	struct mfsnode *mfsp = VTOMFS(vp);
348 	struct buf *bp;
349 	caddr_t base;
350 	int sleepreturn = 0;
351 
352 	base = mfsp->mfs_baseoff;
353 	while (mfsp->mfs_shutdown != 1) {
354 		while ((bp = BUFQ_GET(&mfsp->mfs_buflist)) != NULL) {
355 			mfs_doio(bp, base);
356 			wakeup((caddr_t)bp);
357 		}
358 		/*
359 		 * If a non-ignored signal is received, try to unmount.
360 		 * If that fails, or the filesystem is already in the
361 		 * process of being unmounted, clear the signal (it has been
362 		 * "processed"), otherwise we will loop here, as tsleep
363 		 * will always return EINTR/ERESTART.
364 		 */
365 		if (sleepreturn != 0) {
366 			/*
367 			 * XXX Freeze syncer.  Must do this before locking
368 			 * the mount point.  See dounmount() for details.
369 			 */
370 			lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL);
371 			if (vfs_busy(mp, LK_NOWAIT, 0) != 0)
372 				lockmgr(&syncer_lock, LK_RELEASE, NULL);
373 			else if (dounmount(mp, 0, p) != 0)
374 				CLRSIG(p, CURSIG(p));
375 			sleepreturn = 0;
376 			continue;
377 		}
378 
379 		sleepreturn = tsleep(vp, mfs_pri, "mfsidl", 0);
380 	}
381 	KASSERT(BUFQ_PEEK(&mfsp->mfs_buflist) == NULL);
382 	bufq_free(&mfsp->mfs_buflist);
383 	return (sleepreturn);
384 }
385 
386 /*
387  * Get file system statistics.
388  */
389 int
390 mfs_statfs(mp, sbp, p)
391 	struct mount *mp;
392 	struct statfs *sbp;
393 	struct proc *p;
394 {
395 	int error;
396 
397 	error = ffs_statfs(mp, sbp, p);
398 #ifdef COMPAT_09
399 	sbp->f_type = 3;
400 #else
401 	sbp->f_type = 0;
402 #endif
403 	strncpy(&sbp->f_fstypename[0], mp->mnt_op->vfs_name, MFSNAMELEN);
404 	return (error);
405 }
406