1 /* $NetBSD: mfs_vnops.c,v 1.56 2015/01/14 11:21:31 hannken Exp $ */
2
3 /*
4 * Copyright (c) 1989, 1993
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)mfs_vnops.c 8.11 (Berkeley) 5/22/95
32 */
33
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: mfs_vnops.c,v 1.56 2015/01/14 11:21:31 hannken Exp $");
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/time.h>
40 #include <sys/kernel.h>
41 #include <sys/proc.h>
42 #include <sys/buf.h>
43 #include <sys/bufq.h>
44 #include <sys/vnode.h>
45 #include <sys/kmem.h>
46
47 #include <miscfs/genfs/genfs.h>
48 #include <miscfs/specfs/specdev.h>
49
50 #include <machine/vmparam.h>
51
52 #include <ufs/mfs/mfsnode.h>
53 #include <ufs/mfs/mfs_extern.h>
54
55 /*
56 * mfs vnode operations.
57 */
58 int (**mfs_vnodeop_p)(void *);
59 const struct vnodeopv_entry_desc mfs_vnodeop_entries[] = {
60 { &vop_default_desc, vn_default_error },
61 { &vop_lookup_desc, mfs_lookup }, /* lookup */
62 { &vop_create_desc, mfs_create }, /* create */
63 { &vop_mknod_desc, mfs_mknod }, /* mknod */
64 { &vop_open_desc, mfs_open }, /* open */
65 { &vop_close_desc, mfs_close }, /* close */
66 { &vop_access_desc, mfs_access }, /* access */
67 { &vop_getattr_desc, mfs_getattr }, /* getattr */
68 { &vop_setattr_desc, mfs_setattr }, /* setattr */
69 { &vop_read_desc, mfs_read }, /* read */
70 { &vop_write_desc, mfs_write }, /* write */
71 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */
72 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */
73 { &vop_ioctl_desc, mfs_ioctl }, /* ioctl */
74 { &vop_poll_desc, mfs_poll }, /* poll */
75 { &vop_revoke_desc, mfs_revoke }, /* revoke */
76 { &vop_mmap_desc, mfs_mmap }, /* mmap */
77 { &vop_fsync_desc, spec_fsync }, /* fsync */
78 { &vop_seek_desc, mfs_seek }, /* seek */
79 { &vop_remove_desc, mfs_remove }, /* remove */
80 { &vop_link_desc, mfs_link }, /* link */
81 { &vop_rename_desc, mfs_rename }, /* rename */
82 { &vop_mkdir_desc, mfs_mkdir }, /* mkdir */
83 { &vop_rmdir_desc, mfs_rmdir }, /* rmdir */
84 { &vop_symlink_desc, mfs_symlink }, /* symlink */
85 { &vop_readdir_desc, mfs_readdir }, /* readdir */
86 { &vop_readlink_desc, mfs_readlink }, /* readlink */
87 { &vop_abortop_desc, mfs_abortop }, /* abortop */
88 { &vop_inactive_desc, mfs_inactive }, /* inactive */
89 { &vop_reclaim_desc, mfs_reclaim }, /* reclaim */
90 { &vop_lock_desc, genfs_nolock }, /* lock */
91 { &vop_unlock_desc, genfs_nounlock }, /* unlock */
92 { &vop_bmap_desc, mfs_bmap }, /* bmap */
93 { &vop_strategy_desc, mfs_strategy }, /* strategy */
94 { &vop_print_desc, mfs_print }, /* print */
95 { &vop_islocked_desc, mfs_islocked }, /* islocked */
96 { &vop_pathconf_desc, mfs_pathconf }, /* pathconf */
97 { &vop_advlock_desc, mfs_advlock }, /* advlock */
98 { &vop_bwrite_desc, mfs_bwrite }, /* bwrite */
99 { &vop_putpages_desc, mfs_putpages }, /* putpages */
100 { NULL, NULL }
101 };
102 const struct vnodeopv_desc mfs_vnodeop_opv_desc =
103 { &mfs_vnodeop_p, mfs_vnodeop_entries };
104
105 /*
106 * Vnode Operations.
107 *
108 * Open called to allow memory filesystem to initialize and
109 * validate before actual IO. Record our process identifier
110 * so we can tell when we are doing I/O to ourself.
111 */
112 /* ARGSUSED */
113 int
mfs_open(void * v)114 mfs_open(void *v)
115 {
116 struct vop_open_args /* {
117 struct vnode *a_vp;
118 int a_mode;
119 kauth_cred_t a_cred;
120 } */ *ap = v;
121
122 if (ap->a_vp->v_type != VBLK) {
123 panic("mfs_ioctl not VBLK");
124 /* NOTREACHED */
125 }
126 return (0);
127 }
128
129 /*
130 * Pass I/O requests to the memory filesystem process.
131 */
132 int
mfs_strategy(void * v)133 mfs_strategy(void *v)
134 {
135 struct vop_strategy_args /* {
136 struct vnode *a_vp;
137 struct buf *a_bp;
138 } */ *ap = v;
139 struct vnode *vp = ap->a_vp;
140 struct buf *bp = ap->a_bp;
141 struct mfsnode *mfsp;
142
143 if (vp->v_type != VBLK || vp->v_usecount == 0)
144 panic("mfs_strategy: bad dev");
145 mfsp = VTOMFS(vp);
146 /* check for mini-root access */
147 if (mfsp->mfs_proc == NULL) {
148 void *base;
149
150 base = (char *)mfsp->mfs_baseoff + (bp->b_blkno << DEV_BSHIFT);
151 if (bp->b_flags & B_READ)
152 memcpy(bp->b_data, base, bp->b_bcount);
153 else
154 memcpy(base, bp->b_data, bp->b_bcount);
155 bp->b_resid = 0;
156 biodone(bp);
157 } else if (mfsp->mfs_proc == curproc) {
158 mfs_doio(bp, mfsp->mfs_baseoff);
159 } else if (doing_shutdown) {
160 /*
161 * bitbucket I/O during shutdown.
162 * Note that reads should *not* happen here, but..
163 */
164 if (bp->b_flags & B_READ)
165 printf("warning: mfs read during shutdown\n");
166 bp->b_resid = 0;
167 biodone(bp);
168 } else {
169 mutex_enter(&mfs_lock);
170 bufq_put(mfsp->mfs_buflist, bp);
171 cv_broadcast(&mfsp->mfs_cv);
172 mutex_exit(&mfs_lock);
173 }
174 return (0);
175 }
176
177 /*
178 * Memory file system I/O.
179 */
180 void
mfs_doio(struct buf * bp,void * base)181 mfs_doio(struct buf *bp, void *base)
182 {
183
184 base = (char *)base + (bp->b_blkno << DEV_BSHIFT);
185 if (bp->b_flags & B_READ)
186 bp->b_error = copyin(base, bp->b_data, bp->b_bcount);
187 else
188 bp->b_error = copyout(bp->b_data, base, bp->b_bcount);
189 if (bp->b_error == 0)
190 bp->b_resid = 0;
191 biodone(bp);
192 }
193
194 /*
195 * This is a noop, simply returning what one has been given.
196 */
197 int
mfs_bmap(void * v)198 mfs_bmap(void *v)
199 {
200 struct vop_bmap_args /* {
201 struct vnode *a_vp;
202 daddr_t a_bn;
203 struct vnode **a_vpp;
204 daddr_t *a_bnp;
205 int *a_runp;
206 } */ *ap = v;
207
208 if (ap->a_vpp != NULL)
209 *ap->a_vpp = ap->a_vp;
210 if (ap->a_bnp != NULL)
211 *ap->a_bnp = ap->a_bn;
212 if (ap->a_runp != NULL)
213 *ap->a_runp = 0;
214 return (0);
215 }
216
217 /*
218 * Memory filesystem close routine
219 */
220 /* ARGSUSED */
221 int
mfs_close(void * v)222 mfs_close(void *v)
223 {
224 struct vop_close_args /* {
225 struct vnode *a_vp;
226 int a_fflag;
227 kauth_cred_t a_cred;
228 } */ *ap = v;
229 struct vnode *vp = ap->a_vp;
230 struct mfsnode *mfsp = VTOMFS(vp);
231 struct buf *bp;
232 int error;
233
234 /*
235 * Finish any pending I/O requests.
236 */
237 mutex_enter(&mfs_lock);
238 while ((bp = bufq_get(mfsp->mfs_buflist)) != NULL) {
239 mutex_exit(&mfs_lock);
240 mfs_doio(bp, mfsp->mfs_baseoff);
241 mutex_enter(&mfs_lock);
242 }
243 mutex_exit(&mfs_lock);
244 /*
245 * On last close of a memory filesystem
246 * we must invalidate any in core blocks, so that
247 * we can, free up its vnode.
248 */
249 if ((error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0)) != 0)
250 return (error);
251 /*
252 * There should be no way to have any more uses of this
253 * vnode, so if we find any other uses, it is a panic.
254 */
255 if (bufq_peek(mfsp->mfs_buflist) != NULL)
256 panic("mfs_close");
257 /*
258 * Send a request to the filesystem server to exit.
259 */
260 mutex_enter(&mfs_lock);
261 mfsp->mfs_shutdown = 1;
262 cv_broadcast(&mfsp->mfs_cv);
263 mutex_exit(&mfs_lock);
264 return (0);
265 }
266
267 /*
268 * Memory filesystem inactive routine
269 */
270 /* ARGSUSED */
271 int
mfs_inactive(void * v)272 mfs_inactive(void *v)
273 {
274 struct vop_inactive_args /* {
275 struct vnode *a_vp;
276 } */ *ap = v;
277 struct vnode *vp = ap->a_vp;
278 struct mfsnode *mfsp = VTOMFS(vp);
279
280 if (bufq_peek(mfsp->mfs_buflist) != NULL)
281 panic("mfs_inactive: not inactive (mfs_buflist %p)",
282 bufq_peek(mfsp->mfs_buflist));
283
284 return VOCALL(spec_vnodeop_p, VOFFSET(vop_inactive), ap);
285 }
286
287 /*
288 * Reclaim a memory filesystem devvp so that it can be reused.
289 */
290 int
mfs_reclaim(void * v)291 mfs_reclaim(void *v)
292 {
293 struct vop_reclaim_args /* {
294 struct vnode *a_vp;
295 } */ *ap = v;
296 struct vnode *vp = ap->a_vp;
297 struct mfsnode *mfsp = VTOMFS(vp);
298 int refcnt;
299
300 mutex_enter(&mfs_lock);
301 vp->v_data = NULL;
302 refcnt = --mfsp->mfs_refcnt;
303 mutex_exit(&mfs_lock);
304
305 if (refcnt == 0) {
306 bufq_free(mfsp->mfs_buflist);
307 cv_destroy(&mfsp->mfs_cv);
308 kmem_free(mfsp, sizeof(*mfsp));
309 }
310
311 return VOCALL(spec_vnodeop_p, VOFFSET(vop_reclaim), ap);
312 }
313
314 /*
315 * Print out the contents of an mfsnode.
316 */
317 int
mfs_print(void * v)318 mfs_print(void *v)
319 {
320 struct vop_print_args /* {
321 struct vnode *a_vp;
322 } */ *ap = v;
323 struct mfsnode *mfsp = VTOMFS(ap->a_vp);
324
325 printf("tag VT_MFS, pid %d, base %p, size %ld\n",
326 (mfsp->mfs_proc != NULL) ? mfsp->mfs_proc->p_pid : 0,
327 mfsp->mfs_baseoff, mfsp->mfs_size);
328 return (0);
329 }
330