1 /*        $NetBSD: rump_vfs.c,v 1.97 2023/09/23 18:21:12 ad Exp $     */
2 
3 /*
4  * Copyright (c) 2008 Antti Kantee.  All Rights Reserved.
5  *
6  * Development of this software was supported by the
7  * Finnish Cultural Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
19  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: rump_vfs.c,v 1.97 2023/09/23 18:21:12 ad Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/buf.h>
36 #include <sys/conf.h>
37 #include <sys/evcnt.h>
38 #include <sys/fcntl.h>
39 #include <sys/filedesc.h>
40 #include <sys/fstrans.h>
41 #include <sys/lockf.h>
42 #include <sys/kthread.h>
43 #include <sys/module.h>
44 #include <sys/namei.h>
45 #include <sys/queue.h>
46 #include <sys/stat.h>
47 #include <sys/vfs_syscalls.h>
48 #include <sys/vnode.h>
49 #include <sys/wapbl.h>
50 #include <sys/bufq.h>
51 
52 #include <miscfs/specfs/specdev.h>
53 
54 #include <rump-sys/kern.h>
55 #include <rump-sys/vfs.h>
56 
57 #include <rump/rump.h>
58 #include <rump/rumpuser.h>
59 
60 const char *rootfstype = ROOT_FSTYPE_ANY;
61 
62 static void
pvfs_init(struct proc * p)63 pvfs_init(struct proc *p)
64 {
65 
66           p->p_cwdi = cwdinit();
67 }
68 
69 static void
pvfs_rele(struct proc * p)70 pvfs_rele(struct proc *p)
71 {
72 
73           cwdfree(p->p_cwdi);
74 }
75 
76 static void
fini(void)77 fini(void)
78 {
79 
80           vfs_shutdown();
81           rumpblk_fini();
82 }
83 
84 static void
drainbufs(int npages)85 drainbufs(int npages)
86 {
87 
88           mutex_enter(&bufcache_lock);
89           buf_drain(npages);
90           mutex_exit(&bufcache_lock);
91 }
92 
RUMP_COMPONENT(RUMP__FACTION_VFS)93 RUMP_COMPONENT(RUMP__FACTION_VFS)
94 {
95           extern struct vfsops rumpfs_vfsops;
96           char buf[64];
97           char *mbase;
98           int rv, i;
99 
100           /* initialize indirect interfaces */
101           rump_vfs_fini = fini;
102           rump_vfs_drainbufs = drainbufs;
103 
104           if (rumpuser_getparam("RUMP_NVNODES", buf, sizeof(buf)) == 0) {
105                     desiredvnodes = strtoul(buf, NULL, 10);
106           } else {
107                     desiredvnodes = 1<<10;
108           }
109 
110           rumpblk_init();
111 
112           for (i = 0; i < ncpu; i++) {
113                     struct cpu_info *ci = cpu_lookup(i);
114                     cache_cpu_init(ci);
115           }
116 
117           /* make number of bufpages 5% of total memory limit */
118           if (rump_physmemlimit != RUMPMEM_UNLIMITED) {
119                     extern u_int bufpages;
120                     bufpages = rump_physmemlimit / (20 * PAGE_SIZE);
121           }
122 
123           bufq_init();
124           fstrans_init();
125           vfsinit();
126           bufinit();
127           lf_init();
128           spec_init();
129 
130           root_device = &rump_rootdev;
131 
132           /* bootstrap cwdi (rest done in vfs_mountroot() */
133           proc0.p_cwdi = &cwdi0;
134           proc0.p_cwdi = cwdinit();
135 
136           vfs_attach(&rumpfs_vfsops);
137           vfs_mountroot();
138 
139           /* "mtree": create /dev and /tmp */
140           do_sys_mkdir("/dev", 0755, UIO_SYSSPACE);
141           do_sys_mkdir("/tmp", 01777, UIO_SYSSPACE);
142           do_sys_chmodat(curlwp, AT_FDCWD, "/tmp", 01777, 0);
143 
144           rump_proc_vfs_init = pvfs_init;
145           rump_proc_vfs_release = pvfs_rele;
146 
147           if (rump_threads) {
148                     if ((rv = kthread_create(PRI_IOFLUSH, KTHREAD_MPSAFE, NULL,
149                         sched_sync, NULL, NULL, "ioflush")) != 0)
150                               panic("syncer thread create failed: %d", rv);
151           } else {
152                     syncdelay = 0;
153           }
154 
155           /*
156            * On archs where the native kernel ABI is supported, map
157            * host module directory to rump.  This means that kernel
158            * modules from the host will be autoloaded to rump kernels.
159            */
160           if (rump_nativeabi_p()) {
161                     if (rumpuser_getparam("RUMP_MODULEBASE", buf, sizeof(buf)) == 0)
162                               mbase = buf;
163                     else
164                               mbase = module_base;
165 
166                     if (strlen(mbase) != 0 && *mbase != '0') {
167                               rump_etfs_register(module_base, mbase,
168                                   RUMP_ETFS_DIR_SUBDIRS);
169                     }
170           }
171 
172           module_init_class(MODULE_CLASS_BUFQ);
173           module_init_class(MODULE_CLASS_VFS);
174 
175           /*
176            * Don't build device names for a large set of devices by
177            * default.  While the pseudo-devfs is a fun experiment,
178            * creating many many device nodes may increase rump kernel
179            * bootstrap time by ~40%.  Device nodes should be created
180            * per-demand in the component constructors.
181            */
182 #if 0
183           {
184           extern struct devsw_conv devsw_conv0[];
185           extern int max_devsw_convs;
186           rump_vfs_builddevs(devsw_conv0, max_devsw_convs);
187           }
188 #else
189           rump_vfs_builddevs(NULL, 0);
190 #endif
191 
192           /* attach null device and create /dev/{null,zero} */
193           rump_devnull_init();
194 
195           rump_component_init(RUMP_COMPONENT_VFS);
196 }
197 
198 struct rumpcn {
199           struct componentname rcn_cn;
200           char *rcn_path;
201 };
202 
203 struct componentname *
rump_makecn(u_long nameiop,u_long flags,const char * name,size_t namelen,kauth_cred_t creds,struct lwp * l)204 rump_makecn(u_long nameiop, u_long flags, const char *name, size_t namelen,
205           kauth_cred_t creds, struct lwp *l)
206 {
207           struct rumpcn *rcn;
208           struct componentname *cnp;
209 
210           rcn = kmem_zalloc(sizeof(*rcn), KM_SLEEP);
211           cnp = &rcn->rcn_cn;
212 
213           rcn->rcn_path = PNBUF_GET();
214           strlcpy(rcn->rcn_path, name, MAXPATHLEN);
215           cnp->cn_nameptr = rcn->rcn_path;
216 
217           cnp->cn_nameiop = nameiop;
218           cnp->cn_flags = flags & (MODMASK | PARAMASK);
219 
220           cnp->cn_namelen = namelen;
221 
222           cnp->cn_cred = creds;
223 
224           return cnp;
225 }
226 
227 void
rump_freecn(struct componentname * cnp,int flags)228 rump_freecn(struct componentname *cnp, int flags)
229 {
230           struct rumpcn *rcn = (void *)cnp;
231 
232           if (flags & RUMPCN_FREECRED)
233                     rump_cred_put(cnp->cn_cred);
234 
235           PNBUF_PUT(rcn->rcn_path);
236           kmem_free(rcn, sizeof(*rcn));
237 }
238 
239 /* hey baby, what's your namei? */
240 int
rump_namei(uint32_t op,uint32_t flags,const char * namep,struct vnode ** dvpp,struct vnode ** vpp,struct componentname ** cnpp)241 rump_namei(uint32_t op, uint32_t flags, const char *namep,
242           struct vnode **dvpp, struct vnode **vpp, struct componentname **cnpp)
243 {
244           struct pathbuf *pb;
245           struct nameidata nd;
246           int rv;
247 
248           pb = pathbuf_create(namep);
249           if (pb == NULL) {
250                     return ENOMEM;
251           }
252           NDINIT(&nd, op, flags, pb);
253           rv = namei(&nd);
254           if (rv) {
255                     pathbuf_destroy(pb);
256                     return rv;
257           }
258 
259           if (dvpp) {
260                     KASSERT(flags & LOCKPARENT);
261                     *dvpp = nd.ni_dvp;
262           } else {
263                     KASSERT((flags & LOCKPARENT) == 0);
264           }
265 
266           if (vpp) {
267                     *vpp = nd.ni_vp;
268           } else {
269                     if (nd.ni_vp) {
270                               if (flags & LOCKLEAF)
271                                         vput(nd.ni_vp);
272                               else
273                                         vrele(nd.ni_vp);
274                     }
275           }
276 
277           if (cnpp) {
278                     struct componentname *cnp;
279 
280                     cnp = kmem_alloc(sizeof(*cnp), KM_SLEEP);
281                     memcpy(cnp, &nd.ni_cnd, sizeof(*cnp));
282                     *cnpp = cnp;
283           }
284           pathbuf_destroy(pb);
285 
286           return rv;
287 }
288 
289 void
rump_getvninfo(struct vnode * vp,enum rump_vtype * vtype,voff_t * vsize,dev_t * vdev)290 rump_getvninfo(struct vnode *vp, enum rump_vtype *vtype,
291           voff_t *vsize, dev_t *vdev)
292 {
293 
294           *vtype = (enum rump_vtype)vp->v_type;
295           *vsize = vp->v_size;
296           if (vp->v_specnode)
297                     *vdev = vp->v_rdev;
298           else
299                     *vdev = 0;
300 }
301 
302 struct vfsops *
rump_vfslist_iterate(struct vfsops * ops)303 rump_vfslist_iterate(struct vfsops *ops)
304 {
305 
306           if (ops == NULL)
307                     return LIST_FIRST(&vfs_list);
308           else
309                     return LIST_NEXT(ops, vfs_list);
310 }
311 
312 struct vfsops *
rump_vfs_getopsbyname(const char * name)313 rump_vfs_getopsbyname(const char *name)
314 {
315 
316           return vfs_getopsbyname(name);
317 }
318 
319 int
rump_vfs_getmp(const char * path,struct mount ** mpp)320 rump_vfs_getmp(const char *path, struct mount **mpp)
321 {
322           struct vnode *vp;
323           int rv;
324 
325           if ((rv = namei_simple_user(path, NSM_FOLLOW_TRYEMULROOT, &vp)) != 0)
326                     return rv;
327 
328           *mpp = vp->v_mount;
329           vrele(vp);
330           return 0;
331 }
332 
333 struct vattr*
rump_vattr_init(void)334 rump_vattr_init(void)
335 {
336           struct vattr *vap;
337 
338           vap = kmem_alloc(sizeof(struct vattr), KM_SLEEP);
339           vattr_null(vap);
340 
341           return vap;
342 }
343 
344 void
rump_vattr_settype(struct vattr * vap,enum rump_vtype vt)345 rump_vattr_settype(struct vattr *vap, enum rump_vtype vt)
346 {
347 
348           vap->va_type = (enum vtype)vt;
349 }
350 
351 void
rump_vattr_setmode(struct vattr * vap,mode_t mode)352 rump_vattr_setmode(struct vattr *vap, mode_t mode)
353 {
354 
355           vap->va_mode = mode;
356 }
357 
358 void
rump_vattr_setrdev(struct vattr * vap,dev_t dev)359 rump_vattr_setrdev(struct vattr *vap, dev_t dev)
360 {
361 
362           vap->va_rdev = dev;
363 }
364 
365 void
rump_vattr_free(struct vattr * vap)366 rump_vattr_free(struct vattr *vap)
367 {
368 
369           kmem_free(vap, sizeof(*vap));
370 }
371 
372 void
rump_vp_incref(struct vnode * vp)373 rump_vp_incref(struct vnode *vp)
374 {
375 
376           vref(vp);
377 }
378 
379 int
rump_vp_getref(struct vnode * vp)380 rump_vp_getref(struct vnode *vp)
381 {
382 
383           return vrefcnt(vp);
384 }
385 
386 void
rump_vp_rele(struct vnode * vp)387 rump_vp_rele(struct vnode *vp)
388 {
389 
390           vrele(vp);
391 }
392 
393 void
rump_vp_interlock(struct vnode * vp)394 rump_vp_interlock(struct vnode *vp)
395 {
396 
397           mutex_enter(vp->v_interlock);
398 }
399 
400 void
rump_vp_vmobjlock(struct vnode * vp,int write)401 rump_vp_vmobjlock(struct vnode *vp, int write)
402 {
403 
404           rw_enter(vp->v_uobj.vmobjlock, write ? RW_WRITER : RW_READER);
405 }
406 
407 int
rump_vfs_unmount(struct mount * mp,int mntflags)408 rump_vfs_unmount(struct mount *mp, int mntflags)
409 {
410 
411           return VFS_UNMOUNT(mp, mntflags);
412 }
413 
414 int
rump_vfs_root(struct mount * mp,struct vnode ** vpp,int lock)415 rump_vfs_root(struct mount *mp, struct vnode **vpp, int lock)
416 {
417           int rv;
418 
419           rv = VFS_ROOT(mp, LK_EXCLUSIVE, vpp);
420           if (rv)
421                     return rv;
422 
423           if (!lock)
424                     VOP_UNLOCK(*vpp);
425 
426           return 0;
427 }
428 
429 int
rump_vfs_statvfs(struct mount * mp,struct statvfs * sbp)430 rump_vfs_statvfs(struct mount *mp, struct statvfs *sbp)
431 {
432 
433           return VFS_STATVFS(mp, sbp);
434 }
435 
436 int
rump_vfs_sync(struct mount * mp,int wait,kauth_cred_t cred)437 rump_vfs_sync(struct mount *mp, int wait, kauth_cred_t cred)
438 {
439 
440           return VFS_SYNC(mp, wait ? MNT_WAIT : MNT_NOWAIT, cred);
441 }
442 
443 int
rump_vfs_fhtovp(struct mount * mp,struct fid * fid,struct vnode ** vpp)444 rump_vfs_fhtovp(struct mount *mp, struct fid *fid, struct vnode **vpp)
445 {
446 
447           return VFS_FHTOVP(mp, fid, LK_EXCLUSIVE, vpp);
448 }
449 
450 int
rump_vfs_vptofh(struct vnode * vp,struct fid * fid,size_t * fidsize)451 rump_vfs_vptofh(struct vnode *vp, struct fid *fid, size_t *fidsize)
452 {
453 
454           return VFS_VPTOFH(vp, fid, fidsize);
455 }
456 
457 int
rump_vfs_extattrctl(struct mount * mp,int cmd,struct vnode * vp,int attrnamespace,const char * attrname)458 rump_vfs_extattrctl(struct mount *mp, int cmd, struct vnode *vp,
459           int attrnamespace, const char *attrname)
460 {
461 
462           return VFS_EXTATTRCTL(mp, cmd, vp, attrnamespace, attrname);
463 }
464 
465 /*ARGSUSED*/
466 void
rump_vfs_syncwait(struct mount * mp)467 rump_vfs_syncwait(struct mount *mp)
468 {
469           int n;
470 
471           n = vfs_syncwait();
472           if (n)
473                     printf("syncwait: unsynced buffers: %d\n", n);
474 }
475 
476 /*
477  * Dump info about mount point.  No locking.
478  */
479 static bool
rump_print_selector(void * cl,struct vnode * vp)480 rump_print_selector(void *cl, struct vnode *vp)
481 {
482           int *full = cl;
483 
484           KASSERT(mutex_owned(vp->v_interlock));
485 
486           vfs_vnode_print(vp, *full, (void *)rumpuser_dprintf);
487           return false;
488 }
489 
490 void
rump_vfs_mount_print(const char * path,int full)491 rump_vfs_mount_print(const char *path, int full)
492 {
493 #ifdef DEBUGPRINT
494           struct vnode *mvp;
495           struct vnode_iterator *marker;
496           int error;
497 
498           rumpuser_dprintf("\n==== dumping mountpoint at ``%s'' ====\n\n", path);
499           if ((error = namei_simple_user(path, NSM_FOLLOW_NOEMULROOT, &mvp))!=0) {
500                     rumpuser_dprintf("==== lookup error %d ====\n\n", error);
501                     return;
502           }
503           vfs_mount_print(mvp->v_mount, full, (void *)rumpuser_dprintf);
504           if (full) {
505                     rumpuser_dprintf("\n== dumping vnodes ==\n\n");
506                     vfs_vnode_iterator_init(mvp->v_mount, &marker);
507                     vfs_vnode_iterator_next(marker, rump_print_selector, &full);
508                     vfs_vnode_iterator_destroy(marker);
509           }
510           vrele(mvp);
511           rumpuser_dprintf("\n==== done ====\n\n");
512 #else
513           rumpuser_dprintf("mount dump not supported without DEBUGPRINT\n");
514 #endif
515 }
516 
517 void
rump_biodone(void * arg,size_t count,int error)518 rump_biodone(void *arg, size_t count, int error)
519 {
520           struct buf *bp = arg;
521 
522           bp->b_resid = bp->b_bcount - count;
523           KASSERT(bp->b_resid >= 0);
524           bp->b_error = error;
525 
526           biodone(bp);
527 }
528