xref: /openbsd/sys/ufs/mfs/mfs_vnops.c (revision 5dea098c)
1 /*	$OpenBSD: mfs_vnops.c,v 1.61 2024/04/16 10:04:41 claudio Exp $	*/
2 /*	$NetBSD: mfs_vnops.c,v 1.8 1996/03/17 02:16:32 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1993
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_vnops.c	8.5 (Berkeley) 7/28/94
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/vnode.h>
42 #include <sys/malloc.h>
43 #include <sys/mount.h>
44 #include <sys/specdev.h>
45 
46 #include <ufs/mfs/mfsnode.h>
47 #include <ufs/mfs/mfs_extern.h>
48 
49 /* mfs vnode operations. */
50 const struct vops mfs_vops = {
51         .vop_lookup     = vop_generic_badop,
52         .vop_create     = vop_generic_badop,
53         .vop_mknod      = vop_generic_badop,
54         .vop_open       = mfs_open,
55         .vop_close      = mfs_close,
56         .vop_access     = vop_generic_badop,
57         .vop_getattr    = vop_generic_badop,
58         .vop_setattr    = vop_generic_badop,
59         .vop_read       = vop_generic_badop,
60         .vop_write      = vop_generic_badop,
61         .vop_ioctl      = mfs_ioctl,
62         .vop_kqfilter   = vop_generic_badop,
63         .vop_revoke     = vop_generic_revoke,
64         .vop_fsync      = spec_fsync,
65         .vop_remove     = vop_generic_badop,
66         .vop_link       = vop_generic_badop,
67         .vop_rename     = vop_generic_badop,
68         .vop_mkdir      = vop_generic_badop,
69         .vop_rmdir      = vop_generic_badop,
70         .vop_symlink    = vop_generic_badop,
71         .vop_readdir    = vop_generic_badop,
72         .vop_readlink   = vop_generic_badop,
73         .vop_abortop    = vop_generic_badop,
74         .vop_inactive   = mfs_inactive,
75         .vop_reclaim    = mfs_reclaim,
76         .vop_lock       = nullop,
77         .vop_unlock     = nullop,
78         .vop_islocked   = nullop,
79         .vop_bmap       = vop_generic_bmap,
80         .vop_strategy   = mfs_strategy,
81         .vop_print      = mfs_print,
82         .vop_pathconf   = vop_generic_badop,
83         .vop_advlock    = vop_generic_badop,
84         .vop_bwrite     = vop_generic_bwrite
85 };
86 
87 /*
88  * Vnode Operations.
89  *
90  * Open called to allow memory filesystem to initialize and
91  * validate before actual IO. Record our process identifier
92  * so we can tell when we are doing I/O to ourself.
93  */
94 int
95 mfs_open(void *v)
96 {
97 #ifdef DIAGNOSTIC
98 	struct vop_open_args *ap = v;
99 
100 	if (ap->a_vp->v_type != VBLK) {
101 		panic("mfs_open not VBLK");
102 	}
103 #endif
104 	return (0);
105 }
106 
107 /*
108  * Ioctl operation.
109  */
110 int
111 mfs_ioctl(void *v)
112 {
113 
114 	return (ENOTTY);
115 }
116 
117 /*
118  * Pass I/O requests to the memory filesystem process.
119  */
120 int
121 mfs_strategy(void *v)
122 {
123 	struct vop_strategy_args *ap = v;
124 	struct buf *bp = ap->a_bp;
125 	struct mfsnode *mfsp;
126 	struct vnode *vp = ap->a_vp;
127 
128 	if (vp->v_type != VBLK || vp->v_usecount == 0)
129 		panic("mfs_strategy: bad dev");
130 
131 	mfsp = VTOMFS(vp);
132 	if (mfsp->mfs_tid == curproc->p_tid) {
133 		mfs_doio(mfsp, bp);
134 	} else {
135 		bufq_queue(&mfsp->mfs_bufq, bp);
136 		wakeup(vp);
137 	}
138 	return (0);
139 }
140 
141 /*
142  * Memory file system I/O.
143  */
144 void
145 mfs_doio(struct mfsnode *mfsp, struct buf *bp)
146 {
147 	caddr_t base;
148 	long offset = bp->b_blkno << DEV_BSHIFT;
149 	int s;
150 
151 	if (bp->b_bcount > mfsp->mfs_size - offset)
152 		bp->b_bcount = mfsp->mfs_size - offset;
153 
154 	base = mfsp->mfs_baseoff + offset;
155 	if (bp->b_flags & B_READ)
156 		bp->b_error = copyin(base, bp->b_data, bp->b_bcount);
157 	else
158 		bp->b_error = copyout(bp->b_data, base, bp->b_bcount);
159 	if (bp->b_error)
160 		bp->b_flags |= B_ERROR;
161 	else
162 		bp->b_resid = 0;
163 	s = splbio();
164 	biodone(bp);
165 	splx(s);
166 }
167 
168 /*
169  * Memory filesystem close routine
170  */
171 int
172 mfs_close(void *v)
173 {
174 	struct vop_close_args *ap = v;
175 	struct vnode *vp = ap->a_vp;
176 	struct mfsnode *mfsp = VTOMFS(vp);
177 	struct buf *bp;
178 	int error;
179 
180 	/*
181 	 * Finish any pending I/O requests.
182 	 */
183 	while (1) {
184 		bp = bufq_dequeue(&mfsp->mfs_bufq);
185 		if (bp == NULL)
186 			break;
187 		mfs_doio(mfsp, bp);
188 		wakeup(bp);
189 	}
190 
191 	/*
192 	 * On last close of a memory filesystem we must invalidate any in
193 	 * core blocks, so that we can free up its vnode.
194 	 */
195 	error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, INFSLP);
196 	if (error != 0)
197 		return (error);
198 
199 #ifdef DIAGNOSTIC
200 	/*
201 	 * There should be no way to have any more buffers on this vnode.
202 	 */
203 	if (bufq_peek(&mfsp->mfs_bufq))
204 		printf("mfs_close: dirty buffers\n");
205 #endif
206 
207 	/*
208 	 * Send a request to the filesystem server to exit.
209 	 */
210 	mfsp->mfs_shutdown = 1;
211 	wakeup(vp);
212 	return (0);
213 }
214 
215 /*
216  * Memory filesystem inactive routine
217  */
218 int
219 mfs_inactive(void *v)
220 {
221 	struct vop_inactive_args *ap = v;
222 #ifdef DIAGNOSTIC
223 	struct mfsnode *mfsp = VTOMFS(ap->a_vp);
224 
225 	if (mfsp->mfs_shutdown && bufq_peek(&mfsp->mfs_bufq))
226 		panic("mfs_inactive: not inactive");
227 #endif
228 	VOP_UNLOCK(ap->a_vp);
229 	return (0);
230 }
231 
232 /*
233  * Reclaim a memory filesystem devvp so that it can be reused.
234  */
235 int
236 mfs_reclaim(void *v)
237 {
238 	struct vop_reclaim_args *ap = v;
239 	struct vnode *vp = ap->a_vp;
240 	struct mfsnode *mfsp = VTOMFS(vp);
241 
242 	bufq_destroy(&mfsp->mfs_bufq);
243 
244 	free(vp->v_data, M_MFSNODE, sizeof(struct mfsnode));
245 	vp->v_data = NULL;
246 	return (0);
247 }
248 
249 /*
250  * Print out the contents of an mfsnode.
251  */
252 int
253 mfs_print(void *v)
254 {
255 	struct vop_print_args *ap = v;
256 	struct mfsnode *mfsp = VTOMFS(ap->a_vp);
257 
258 	printf("tag VT_MFS, tid %d, base %p, size %ld\n", mfsp->mfs_tid,
259 	    mfsp->mfs_baseoff, mfsp->mfs_size);
260 	return (0);
261 }
262