xref: /freebsd/sys/ufs/ffs/ffs_vnops.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
1 /*
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)ffs_vnops.c	8.15 (Berkeley) 5/14/95
34  * $FreeBSD$
35  */
36 
37 #include "opt_ufs.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/resourcevar.h>
42 #include <sys/signalvar.h>
43 #include <sys/kernel.h>
44 #include <sys/stat.h>
45 #include <sys/bio.h>
46 #include <sys/buf.h>
47 #include <sys/proc.h>
48 #include <sys/mount.h>
49 #include <sys/vnode.h>
50 #include <sys/conf.h>
51 
52 #include <machine/limits.h>
53 
54 #include <vm/vm.h>
55 #include <vm/vm_page.h>
56 #include <vm/vm_object.h>
57 #include <vm/vm_extern.h>
58 
59 #include <ufs/ufs/extattr.h>
60 #include <ufs/ufs/quota.h>
61 #include <ufs/ufs/inode.h>
62 #include <ufs/ufs/ufsmount.h>
63 #include <ufs/ufs/ufs_extern.h>
64 
65 #include <ufs/ffs/fs.h>
66 #include <ufs/ffs/ffs_extern.h>
67 
68 int	ffs_fsync(struct vop_fsync_args *);
69 static int	ffs_getpages(struct vop_getpages_args *);
70 static int	ffs_read(struct vop_read_args *);
71 static int	ffs_write(struct vop_write_args *);
72 
73 /* Global vfs data structures for ufs. */
74 vop_t **ffs_vnodeop_p;
75 static struct vnodeopv_entry_desc ffs_vnodeop_entries[] = {
76 	{ &vop_default_desc,		(vop_t *) ufs_vnoperate },
77 	{ &vop_fsync_desc,		(vop_t *) ffs_fsync },
78 	{ &vop_getpages_desc,		(vop_t *) ffs_getpages },
79 	{ &vop_read_desc,		(vop_t *) ffs_read },
80 	{ &vop_reallocblks_desc,	(vop_t *) ffs_reallocblks },
81 	{ &vop_write_desc,		(vop_t *) ffs_write },
82 	{ NULL, NULL }
83 };
84 static struct vnodeopv_desc ffs_vnodeop_opv_desc =
85 	{ &ffs_vnodeop_p, ffs_vnodeop_entries };
86 
87 vop_t **ffs_specop_p;
88 static struct vnodeopv_entry_desc ffs_specop_entries[] = {
89 	{ &vop_default_desc,		(vop_t *) ufs_vnoperatespec },
90 	{ &vop_fsync_desc,		(vop_t *) ffs_fsync },
91 	{ NULL, NULL }
92 };
93 static struct vnodeopv_desc ffs_specop_opv_desc =
94 	{ &ffs_specop_p, ffs_specop_entries };
95 
96 vop_t **ffs_fifoop_p;
97 static struct vnodeopv_entry_desc ffs_fifoop_entries[] = {
98 	{ &vop_default_desc,		(vop_t *) ufs_vnoperatefifo },
99 	{ &vop_fsync_desc,		(vop_t *) ffs_fsync },
100 	{ NULL, NULL }
101 };
102 static struct vnodeopv_desc ffs_fifoop_opv_desc =
103 	{ &ffs_fifoop_p, ffs_fifoop_entries };
104 
105 VNODEOP_SET(ffs_vnodeop_opv_desc);
106 VNODEOP_SET(ffs_specop_opv_desc);
107 VNODEOP_SET(ffs_fifoop_opv_desc);
108 
109 #include <ufs/ufs/ufs_readwrite.c>
110 
111 /*
112  * Synch an open file.
113  */
114 /* ARGSUSED */
115 int
116 ffs_fsync(ap)
117 	struct vop_fsync_args /* {
118 		struct vnode *a_vp;
119 		struct ucred *a_cred;
120 		int a_waitfor;
121 		struct thread *a_td;
122 	} */ *ap;
123 {
124 	struct vnode *vp = ap->a_vp;
125 	struct inode *ip = VTOI(vp);
126 	struct buf *bp;
127 	struct buf *nbp;
128 	int s, error, wait, passes, skipmeta;
129 	ufs_lbn_t lbn;
130 
131 	wait = (ap->a_waitfor == MNT_WAIT);
132 	if (vn_isdisk(vp, NULL)) {
133 		lbn = INT_MAX;
134 		if (vp->v_rdev->si_mountpoint != NULL &&
135 		    (vp->v_rdev->si_mountpoint->mnt_flag & MNT_SOFTDEP))
136 			softdep_fsync_mountdev(vp);
137 	} else {
138 		lbn = lblkno(ip->i_fs, (ip->i_size + ip->i_fs->fs_bsize - 1));
139 	}
140 
141 	/*
142 	 * Flush all dirty buffers associated with a vnode.
143 	 */
144 	passes = NIADDR + 1;
145 	skipmeta = 0;
146 	if (wait)
147 		skipmeta = 1;
148 	s = splbio();
149 loop:
150 	TAILQ_FOREACH(bp, &vp->v_dirtyblkhd, b_vnbufs)
151 		bp->b_flags &= ~B_SCANNED;
152 	for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
153 		nbp = TAILQ_NEXT(bp, b_vnbufs);
154 		/*
155 		 * Reasons to skip this buffer: it has already been considered
156 		 * on this pass, this pass is the first time through on a
157 		 * synchronous flush request and the buffer being considered
158 		 * is metadata, the buffer has dependencies that will cause
159 		 * it to be redirtied and it has not already been deferred,
160 		 * or it is already being written.
161 		 */
162 		if ((bp->b_flags & B_SCANNED) != 0)
163 			continue;
164 		bp->b_flags |= B_SCANNED;
165 		if ((skipmeta == 1 && bp->b_lblkno < 0))
166 			continue;
167 		if (!wait && LIST_FIRST(&bp->b_dep) != NULL &&
168 		    (bp->b_flags & B_DEFERRED) == 0 &&
169 		    buf_countdeps(bp, 0)) {
170 			bp->b_flags |= B_DEFERRED;
171 			continue;
172 		}
173 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT))
174 			continue;
175 		if ((bp->b_flags & B_DELWRI) == 0)
176 			panic("ffs_fsync: not dirty");
177 		if (vp != bp->b_vp)
178 			panic("ffs_fsync: vp != vp->b_vp");
179 		/*
180 		 * If this is a synchronous flush request, or it is not a
181 		 * file or device, start the write on this buffer immediatly.
182 		 */
183 		if (wait || (vp->v_type != VREG && vp->v_type != VBLK)) {
184 
185 			/*
186 			 * On our final pass through, do all I/O synchronously
187 			 * so that we can find out if our flush is failing
188 			 * because of write errors.
189 			 */
190 			if (passes > 0 || !wait) {
191 				if ((bp->b_flags & B_CLUSTEROK) && !wait) {
192 					BUF_UNLOCK(bp);
193 					(void) vfs_bio_awrite(bp);
194 				} else {
195 					bremfree(bp);
196 					splx(s);
197 					(void) bawrite(bp);
198 					s = splbio();
199 				}
200 			} else {
201 				bremfree(bp);
202 				splx(s);
203 				if ((error = bwrite(bp)) != 0)
204 					return (error);
205 				s = splbio();
206 			}
207 		} else if ((vp->v_type == VREG) && (bp->b_lblkno >= lbn)) {
208 			/*
209 			 * If the buffer is for data that has been truncated
210 			 * off the file, then throw it away.
211 			 */
212 			bremfree(bp);
213 			bp->b_flags |= B_INVAL | B_NOCACHE;
214 			splx(s);
215 			brelse(bp);
216 			s = splbio();
217 		} else {
218 			BUF_UNLOCK(bp);
219 			vfs_bio_awrite(bp);
220 		}
221 		/*
222 		 * Since we may have slept during the I/O, we need
223 		 * to start from a known point.
224 		 */
225 		nbp = TAILQ_FIRST(&vp->v_dirtyblkhd);
226 	}
227 	/*
228 	 * If we were asked to do this synchronously, then go back for
229 	 * another pass, this time doing the metadata.
230 	 */
231 	if (skipmeta) {
232 		skipmeta = 0;
233 		goto loop;
234 	}
235 
236 	if (wait) {
237 		while (vp->v_numoutput) {
238 			vp->v_flag |= VBWAIT;
239 			(void) tsleep((caddr_t)&vp->v_numoutput,
240 					PRIBIO + 4, "ffsfsn", 0);
241   		}
242 
243 		/*
244 		 * Ensure that any filesystem metatdata associated
245 		 * with the vnode has been written.
246 		 */
247 		splx(s);
248 		if ((error = softdep_sync_metadata(ap)) != 0)
249 			return (error);
250 		s = splbio();
251 
252 		if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
253 			/*
254 			 * Block devices associated with filesystems may
255 			 * have new I/O requests posted for them even if
256 			 * the vnode is locked, so no amount of trying will
257 			 * get them clean. Thus we give block devices a
258 			 * good effort, then just give up. For all other file
259 			 * types, go around and try again until it is clean.
260 			 */
261 			if (passes > 0) {
262 				passes -= 1;
263 				goto loop;
264 			}
265 #ifdef DIAGNOSTIC
266 			if (!vn_isdisk(vp, NULL))
267 				vprint("ffs_fsync: dirty", vp);
268 #endif
269 		}
270 	}
271 	splx(s);
272 	return (UFS_UPDATE(vp, wait));
273 }
274