1 /*        $NetBSD: sysvbfs_vfsops.c,v 1.48 2022/05/03 07:34:38 hannken Exp $    */
2 
3 /*-
4  * Copyright (c) 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by UCHIYAMA Yasushi.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: sysvbfs_vfsops.c,v 1.48 2022/05/03 07:34:38 hannken Exp $");
34 
35 #include <sys/types.h>
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/pool.h>
39 #include <sys/time.h>
40 #include <sys/ucred.h>
41 #include <sys/mount.h>
42 #include <sys/fcntl.h>
43 #include <sys/malloc.h>
44 #include <sys/kauth.h>
45 #include <sys/proc.h>
46 
47 /* v-node */
48 #include <sys/namei.h>
49 #include <sys/vnode.h>
50 /* devsw */
51 #include <sys/conf.h>
52 
53 #include <fs/sysvbfs/sysvbfs.h>         /* external interface */
54 #include <fs/sysvbfs/bfs.h>   /* internal interface */
55 
56 #ifdef SYSVBFS_VNOPS_DEBUG
57 #define   DPRINTF(fmt, args...)         printf(fmt, ##args)
58 #else
59 #define   DPRINTF(arg...)               ((void)0)
60 #endif
61 
62 MALLOC_JUSTDEFINE(M_SYSVBFS_VFS, "sysvbfs vfs", "sysvbfs vfs structures");
63 
64 struct pool sysvbfs_node_pool;
65 
66 int sysvbfs_mountfs(struct vnode *, struct mount *, struct lwp *);
67 
68 int
sysvbfs_mount(struct mount * mp,const char * path,void * data,size_t * data_len)69 sysvbfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len)
70 {
71           struct lwp *l = curlwp;
72           struct sysvbfs_args *args = data;
73           struct sysvbfs_mount *bmp = NULL;
74           struct vnode *devvp = NULL;
75           int error = 0;
76           bool update;
77 
78           DPRINTF("%s: mnt_flag=%x\n", __func__, mp->mnt_flag);
79 
80           if (args == NULL)
81                     return EINVAL;
82           if (*data_len < sizeof *args)
83                     return EINVAL;
84 
85           if (mp->mnt_flag & MNT_GETARGS) {
86                     if ((bmp = (struct sysvbfs_mount *)mp->mnt_data) == NULL)
87                               return EIO;
88                     args->fspec = NULL;
89                     *data_len = sizeof *args;
90                     return 0;
91           }
92 
93 
94           DPRINTF("%s: args->fspec=%s\n", __func__, args->fspec);
95           update = mp->mnt_flag & MNT_UPDATE;
96           if (args->fspec == NULL) {
97                     /* nothing to do. */
98                     return EINVAL;
99           }
100 
101           if (args->fspec != NULL) {
102                     /* Look up the name and verify that it's sane. */
103                     error = namei_simple_user(args->fspec,
104                                                   NSM_FOLLOW_NOEMULROOT, &devvp);
105                     if (error != 0)
106                               return (error);
107 
108                     if (!update) {
109                               /*
110                                * Be sure this is a valid block device
111                                */
112                               if (devvp->v_type != VBLK)
113                                         error = ENOTBLK;
114                               else if (bdevsw_lookup(devvp->v_rdev) == NULL)
115                                         error = ENXIO;
116                     } else {
117                               /*
118                                * Be sure we're still naming the same device
119                                * used for our initial mount
120                                */
121                               bmp = (struct sysvbfs_mount *)mp->mnt_data;
122                               if (devvp != bmp->devvp)
123                                         error = EINVAL;
124                     }
125           }
126 
127           /*
128            * If mount by non-root, then verify that user has necessary
129            * permissions on the device.
130            *
131            * Permission to update a mount is checked higher, so here we presume
132            * updating the mount is okay (for example, as far as securelevel goes)
133            * which leaves us with the normal check.
134            */
135           if (error == 0) {
136                     int accessmode = VREAD;
137                     if (update ?
138                         (mp->mnt_iflag & IMNT_WANTRDWR) != 0 :
139                         (mp->mnt_flag & MNT_RDONLY) == 0)
140                               accessmode |= VWRITE;
141 
142                     vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
143                     error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT,
144                         KAUTH_REQ_SYSTEM_MOUNT_DEVICE, mp, devvp,
145                         KAUTH_ARG(accessmode));
146                     VOP_UNLOCK(devvp);
147           }
148 
149           if (error) {
150                     vrele(devvp);
151                     return error;
152           }
153 
154           if (!update) {
155                     if ((error = sysvbfs_mountfs(devvp, mp, l)) != 0) {
156                               vrele(devvp);
157                               return error;
158                     }
159           } else    if (mp->mnt_flag & MNT_RDONLY) {
160                     /* XXX: r/w -> read only */
161           }
162 
163           return set_statvfs_info(path, UIO_USERSPACE, args->fspec, UIO_USERSPACE,
164               mp->mnt_op->vfs_name, mp, l);
165 }
166 
167 int
sysvbfs_mountfs(struct vnode * devvp,struct mount * mp,struct lwp * l)168 sysvbfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l)
169 {
170           kauth_cred_t cred = l->l_cred;
171           struct sysvbfs_mount *bmp;
172           int error, oflags;
173 
174           vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
175           error = vinvalbuf(devvp, V_SAVE, cred, l, 0, 0);
176           if (error)
177                     goto out;
178 
179           /* Open block device */
180           oflags = FREAD;
181           if ((mp->mnt_flag & MNT_RDONLY) == 0)
182                     oflags |= FWRITE;
183           if ((error = VOP_OPEN(devvp, oflags, NOCRED)) != 0)
184                     goto out;
185 
186           bmp = malloc(sizeof(*bmp), M_SYSVBFS_VFS, M_WAITOK | M_ZERO);
187           bmp->devvp = devvp;
188           bmp->mountp = mp;
189           if ((error = sysvbfs_bfs_init(&bmp->bfs, devvp)) != 0) {
190                     free(bmp, M_SYSVBFS_VFS);
191                     VOP_CLOSE(devvp, oflags, NOCRED);
192                     goto out;
193           }
194 
195           mp->mnt_data = bmp;
196           mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)devvp->v_rdev;
197           mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_SYSVBFS);
198           mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
199           mp->mnt_stat.f_namemax = BFS_FILENAME_MAXLEN;
200           mp->mnt_flag |= MNT_LOCAL;
201           mp->mnt_dev_bshift = BFS_BSHIFT;
202           mp->mnt_fs_bshift = BFS_BSHIFT;
203 
204  out:
205           VOP_UNLOCK(devvp);
206           return error;
207 }
208 
209 int
sysvbfs_start(struct mount * mp,int flags)210 sysvbfs_start(struct mount *mp, int flags)
211 {
212 
213           DPRINTF("%s:\n", __func__);
214           /* Nothing to do. */
215           return 0;
216 }
217 
218 int
sysvbfs_unmount(struct mount * mp,int mntflags)219 sysvbfs_unmount(struct mount *mp, int mntflags)
220 {
221           struct sysvbfs_mount *bmp = (void *)mp->mnt_data;
222           int error;
223 
224           DPRINTF("%s: %p\n", __func__, bmp);
225 
226           if ((error = vflush(mp, NULLVP,
227               mntflags & MNT_FORCE ? FORCECLOSE : 0)) != 0)
228                     return error;
229 
230           vn_lock(bmp->devvp, LK_EXCLUSIVE | LK_RETRY);
231           error = VOP_CLOSE(bmp->devvp, FREAD, NOCRED);
232           vput(bmp->devvp);
233 
234           sysvbfs_bfs_fini(bmp->bfs);
235 
236           free(bmp, M_SYSVBFS_VFS);
237           mp->mnt_data = NULL;
238           mp->mnt_flag &= ~MNT_LOCAL;
239 
240           return 0;
241 }
242 
243 int
sysvbfs_root(struct mount * mp,int lktype,struct vnode ** vpp)244 sysvbfs_root(struct mount *mp, int lktype, struct vnode **vpp)
245 {
246           struct vnode *vp;
247           int error;
248 
249           DPRINTF("%s:\n", __func__);
250           if ((error = VFS_VGET(mp, BFS_ROOT_INODE, lktype, &vp)) != 0)
251                     return error;
252           *vpp = vp;
253 
254           return 0;
255 }
256 
257 int
sysvbfs_statvfs(struct mount * mp,struct statvfs * f)258 sysvbfs_statvfs(struct mount *mp, struct statvfs *f)
259 {
260           struct sysvbfs_mount *bmp = mp->mnt_data;
261           struct bfs *bfs = bmp->bfs;
262           int free_block;
263           size_t data_block;
264 
265           data_block = (bfs->data_end - bfs->data_start) >> BFS_BSHIFT;
266           if (bfs_inode_alloc(bfs, 0, 0, &free_block) != 0)
267                     free_block = 0;
268           else
269                     free_block = (bfs->data_end >> BFS_BSHIFT) - free_block;
270 
271           DPRINTF("%s: %d %d %d\n", __func__, bfs->data_start,
272               bfs->data_end, free_block);
273 
274           f->f_bsize = BFS_BSIZE;
275           f->f_frsize = BFS_BSIZE;
276           f->f_iosize = BFS_BSIZE;
277           f->f_blocks = data_block;
278           f->f_bfree = free_block;
279           f->f_bavail = f->f_bfree;
280           f->f_bresvd = 0;
281           f->f_files = bfs->max_inode;
282           f->f_ffree = bfs->max_inode - bfs->n_inode;
283           f->f_favail = f->f_ffree;
284           f->f_fresvd = 0;
285           copy_statvfs_info(f, mp);
286 
287           return 0;
288 }
289 
290 int
sysvbfs_sync(struct mount * mp,int waitfor,kauth_cred_t cred)291 sysvbfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred)
292 {
293           struct vnode_iterator *marker;
294           struct vnode *vp;
295           int err, error;
296 
297           DPRINTF("%s:\n", __func__);
298           error = 0;
299           vfs_vnode_iterator_init(mp, &marker);
300           while ((vp = vfs_vnode_iterator_next(marker, NULL, NULL)) != NULL) {
301                     err = vn_lock(vp, LK_EXCLUSIVE);
302                     if (err) {
303                               vrele(vp);
304                               continue;
305                     }
306                     err = VOP_FSYNC(vp, cred, FSYNC_WAIT, 0, 0);
307                     vput(vp);
308                     if (err != 0)
309                               error = err;
310           }
311           vfs_vnode_iterator_destroy(marker);
312 
313           return error;
314 }
315 
316 int
sysvbfs_loadvnode(struct mount * mp,struct vnode * vp,const void * key,size_t key_len,const void ** new_key)317 sysvbfs_loadvnode(struct mount *mp, struct vnode *vp,
318     const void *key, size_t key_len, const void **new_key)
319 {
320           struct sysvbfs_mount *bmp;
321           struct bfs *bfs;
322           struct sysvbfs_node *bnode;
323           struct bfs_inode *inode;
324           uint16_t ino;
325 
326           KASSERT(key_len == sizeof(ino));
327           memcpy(&ino, key, key_len);
328 
329           DPRINTF("%s: i-node=%u\n", __func__, ino);
330 
331           bmp = mp->mnt_data;
332           bfs = bmp->bfs;
333 
334           /* Lookup requested i-node */
335           if (!bfs_inode_lookup(bfs, ino, &inode)) {
336                     DPRINTF("%s: bfs_inode_lookup failed.\n", __func__);
337                     return ENOENT;
338           }
339 
340           bnode = pool_get(&sysvbfs_node_pool, PR_WAITOK);
341           memset(bnode, 0, sizeof(*bnode));
342 
343           vp->v_tag = VT_SYSVBFS;
344           vp->v_op = sysvbfs_vnodeop_p;
345           vp->v_data = bnode;
346           if (ino == BFS_ROOT_INODE) {  /* BFS is flat filesystem */
347                     vp->v_type = VDIR;
348                     vp->v_vflag |= VV_ROOT;
349           } else {
350                     vp->v_type = VREG;
351           }
352 
353           bnode->vnode = vp;
354           bnode->bmp = bmp;
355           bnode->inode = inode;
356           bnode->lockf = NULL; /* advlock */
357 
358           genfs_node_init(vp, &sysvbfs_genfsops);
359           uvm_vnp_setsize(vp, bfs_file_size(inode));
360 
361           *new_key = &bnode->inode->number;
362 
363           return 0;
364 }
365 
366 int
sysvbfs_vget(struct mount * mp,ino_t ino,int lktype,struct vnode ** vpp)367 sysvbfs_vget(struct mount *mp, ino_t ino, int lktype, struct vnode **vpp)
368 {
369           int error;
370           uint16_t number;
371           struct vnode *vp;
372 
373           KASSERT(ino <= UINT16_MAX);
374           number = ino;
375 
376           DPRINTF("%s: i-node=%u\n", __func__, number);
377 
378           error = vcache_get(mp, &number, sizeof(number), &vp);
379           if (error)
380                     return error;
381           error = vn_lock(vp, lktype);
382           if (error) {
383                     vrele(vp);
384                     return error;
385           }
386 
387           *vpp = vp;
388 
389           return 0;
390 }
391 
392 int
sysvbfs_fhtovp(struct mount * mp,struct fid * fid,int lktype,struct vnode ** vpp)393 sysvbfs_fhtovp(struct mount *mp, struct fid *fid, int lktype,
394     struct vnode **vpp)
395 {
396 
397           DPRINTF("%s:\n", __func__);
398           /* notyet */
399           return EOPNOTSUPP;
400 }
401 
402 int
sysvbfs_vptofh(struct vnode * vpp,struct fid * fid,size_t * fh_size)403 sysvbfs_vptofh(struct vnode *vpp, struct fid *fid, size_t *fh_size)
404 {
405 
406           DPRINTF("%s:\n", __func__);
407           /* notyet */
408           return EOPNOTSUPP;
409 }
410 
411 MALLOC_DECLARE(M_BFS);
412 MALLOC_DECLARE(M_SYSVBFS_VNODE);
413 
414 void
sysvbfs_init(void)415 sysvbfs_init(void)
416 {
417 
418           DPRINTF("%s:\n", __func__);
419           malloc_type_attach(M_SYSVBFS_VFS);
420           malloc_type_attach(M_BFS);
421           malloc_type_attach(M_SYSVBFS_VNODE);
422           pool_init(&sysvbfs_node_pool, sizeof(struct sysvbfs_node), 0, 0, 0,
423               "sysvbfs_node_pool", &pool_allocator_nointr, IPL_NONE);
424 }
425 
426 void
sysvbfs_reinit(void)427 sysvbfs_reinit(void)
428 {
429 
430           /* Nothing to do. */
431           DPRINTF("%s:\n", __func__);
432 }
433 
434 void
sysvbfs_done(void)435 sysvbfs_done(void)
436 {
437 
438           DPRINTF("%s:\n", __func__);
439           pool_destroy(&sysvbfs_node_pool);
440           malloc_type_detach(M_BFS);
441           malloc_type_detach(M_SYSVBFS_VFS);
442           malloc_type_detach(M_SYSVBFS_VNODE);
443 }
444 
445 int
sysvbfs_gop_alloc(struct vnode * vp,off_t off,off_t len,int flags,kauth_cred_t cred)446 sysvbfs_gop_alloc(struct vnode *vp, off_t off, off_t len, int flags,
447     kauth_cred_t cred)
448 {
449 
450           return 0;
451 }
452