xref: /netbsd-src/sys/fs/v7fs/v7fs_vnops.c (revision ca453df649ce9db45b64d73678ba06cbccf9aa11)
1 /*	$NetBSD: v7fs_vnops.c,v 1.4 2011/07/16 12:35:40 uch Exp $	*/
2 
3 /*-
4  * Copyright (c) 2004, 2011 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: v7fs_vnops.c,v 1.4 2011/07/16 12:35:40 uch Exp $");
34 #if defined _KERNEL_OPT
35 #include "opt_v7fs.h"
36 #endif
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/resource.h>
41 #include <sys/vnode.h>
42 #include <sys/namei.h>
43 #include <sys/dirent.h>
44 #include <sys/malloc.h>
45 #include <sys/lockf.h>
46 #include <sys/unistd.h>
47 #include <sys/fcntl.h>
48 #include <sys/kauth.h>
49 #include <sys/buf.h>
50 #include <sys/stat.h>	/*APPEND */
51 #include <miscfs/genfs/genfs.h>
52 
53 #include <fs/v7fs/v7fs.h>
54 #include <fs/v7fs/v7fs_impl.h>
55 #include <fs/v7fs/v7fs_inode.h>
56 #include <fs/v7fs/v7fs_dirent.h>
57 #include <fs/v7fs/v7fs_file.h>
58 #include <fs/v7fs/v7fs_datablock.h>
59 #include <fs/v7fs/v7fs_extern.h>
60 
61 #ifdef V7FS_VNOPS_DEBUG
62 #define	DPRINTF(fmt, args...)	printf("%s: " fmt, __func__, ##args)
63 #else
64 #define	DPRINTF(arg...)		((void)0)
65 #endif
66 
67 MALLOC_JUSTDEFINE(M_V7FS_VNODE, "v7fs vnode", "v7fs vnode structures");
68 MALLOC_DECLARE(M_V7FS);
69 
70 static v7fs_mode_t vtype_to_v7fs_mode(enum vtype);
71 static uint8_t v7fs_mode_to_d_type(v7fs_mode_t);
72 
73 static v7fs_mode_t
74 vtype_to_v7fs_mode(enum vtype type)
75 {
76 	/* Convert Vnode types to V7FS types (sys/vnode.h)*/
77 	v7fs_mode_t table[] = { 0, V7FS_IFREG, V7FS_IFDIR, V7FS_IFBLK,
78 				V7FS_IFCHR, V7FSBSD_IFLNK, V7FSBSD_IFSOCK,
79 				V7FSBSD_IFFIFO };
80 	return table[type];
81 }
82 
83 static uint8_t
84 v7fs_mode_to_d_type(v7fs_mode_t mode)
85 {
86 	/* Convert V7FS types to dirent d_type (sys/dirent.h)*/
87 
88 	return (mode & V7FS_IFMT) >> 12;
89 }
90 
91 int
92 v7fs_lookup(void *v)
93 {
94 	struct vop_lookup_args /* {
95 				  struct vnode *a_dvp;
96 				  struct vnode **a_vpp;
97 				  struct componentname *a_cnp;
98 				  } */ *a = v;
99 	struct vnode *dvp = a->a_dvp;
100 	struct v7fs_node *parent_node = dvp->v_data;
101 	struct v7fs_inode *parent = &parent_node->inode;
102 	struct v7fs_self *fs = parent_node->v7fsmount->core;/* my filesystem */
103 	struct vnode *vpp;
104 	struct componentname *cnp = a->a_cnp;
105 	int nameiop = cnp->cn_nameiop;
106 	const char *name = cnp->cn_nameptr;
107 	int namelen = cnp->cn_namelen;
108 	int flags = cnp->cn_flags;
109 	bool isdotdot = flags & ISDOTDOT;
110 	bool islastcn = flags & ISLASTCN;
111 	v7fs_ino_t ino;
112 	int error;
113 
114 	DPRINTF("%s op=%d flags=%d parent=%d %o %dbyte\n", name,
115 	    nameiop, cnp->cn_flags, parent->inode_number, parent->mode,
116 	    parent->filesize);
117 
118 	*a->a_vpp = 0;
119 
120 	/* Check directory permission for search */
121 	if ((error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred))) {
122 		DPRINTF("***perm.\n");
123 		return error;
124 	}
125 
126 	/* Deny last component write operation on a read-only mount */
127 	if (islastcn && (dvp->v_mount->mnt_flag & MNT_RDONLY) &&
128 	    (nameiop == DELETE || nameiop == RENAME)) {
129 		DPRINTF("***ROFS.\n");
130 		return EROFS;
131 	}
132 
133 	/* "." */
134 	if (namelen == 1 && name[0] == '.') {
135 		vref(dvp); /* v_usecount++ */
136 		*a->a_vpp = dvp;
137 		DPRINTF("done.(.)\n");
138 		return 0;
139 	}
140 
141 	/* ".." and reguler file. */
142 	if ((error = v7fs_file_lookup_by_name(fs, parent, name, &ino))) {
143 		/* Not found. Tell this entry be able to allocate. */
144 		if (((nameiop == CREATE) || (nameiop == RENAME)) && islastcn) {
145 			/* Check directory permission to allocate. */
146 			if ((error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred))) {
147 				DPRINTF("access denied. (%s)\n", name);
148 				return error;
149 			}
150 			DPRINTF("EJUSTRETURN op=%d (%s)\n", nameiop, name);
151 			return EJUSTRETURN;
152 		}
153 		DPRINTF("lastcn=%d\n", flags & ISLASTCN);
154 		return error;
155 	}
156 
157 	/* Entry found. Allocate v-node */
158 	// Check permissions?
159 	vpp = 0;
160 	if (isdotdot) {
161 		VOP_UNLOCK(dvp); /* preserve reference count. (not vput) */
162 	}
163 	DPRINTF("enter vget\n");
164 	if ((error = v7fs_vget(dvp->v_mount, ino, &vpp))) {
165 		DPRINTF("***can't get vnode.\n");
166 		return error;
167 	}
168 	DPRINTF("exit vget\n");
169 	if (isdotdot) {
170 		vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY);
171 	}
172 	*a->a_vpp = vpp;
173 	DPRINTF("done.\n");
174 
175 	return 0;
176 }
177 
178 int
179 v7fs_create(void *v)
180 {
181 	struct vop_create_args /* {
182 				  struct vnode *a_dvp;
183 				  struct vnode **a_vpp;
184 				  struct componentname *a_cnp;
185 				  struct vattr *a_vap;
186 				  } */ *a = v;
187 	struct v7fs_node *parent_node = a->a_dvp->v_data;
188 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
189 	struct v7fs_self *fs = v7fsmount->core;
190 	struct mount *mp = v7fsmount->mountp;
191 	struct v7fs_fileattr attr;
192 	struct vattr *va = a->a_vap;
193 	kauth_cred_t cr = a->a_cnp->cn_cred;
194 	v7fs_ino_t ino;
195 	int error = 0;
196 
197 	DPRINTF("%s parent#%d\n", a->a_cnp->cn_nameptr,
198 	    parent_node->inode.inode_number);
199 	KDASSERT((va->va_type == VREG) || (va->va_type == VSOCK));
200 
201 	memset(&attr, 0, sizeof(attr));
202 	attr.uid = kauth_cred_geteuid(cr);
203 	attr.gid = kauth_cred_getegid(cr);
204 	attr.mode = va->va_mode | vtype_to_v7fs_mode (va->va_type);
205 	attr.device = 0;
206 
207 	/* Allocate disk entry. and register its entry to parent directory. */
208 	if ((error = v7fs_file_allocate(fs, &parent_node->inode,
209 		    a->a_cnp->cn_nameptr, &attr, &ino))) {
210 		DPRINTF("v7fs_file_allocate failed.\n");
211 		goto unlock_exit;
212 	}
213 	/* Sync dirent size change. */
214 	uvm_vnp_setsize(a->a_dvp, v7fs_inode_filesize(&parent_node->inode));
215 
216 	/* Get myself vnode. */
217 	*a->a_vpp = 0;
218 	if ((error = v7fs_vget(mp, ino, a->a_vpp))) {
219 		DPRINTF("v7fs_vget failed.\n");
220 		goto unlock_exit;
221 	}
222 
223 	/* Scheduling update time. real update by v7fs_update */
224 	struct v7fs_node *newnode = (*a->a_vpp)->v_data;
225 	newnode->update_ctime = true;
226 	newnode->update_mtime = true;
227 	newnode->update_atime = true;
228 	DPRINTF("allocated %s->#%d\n", a->a_cnp->cn_nameptr, ino);
229 
230 unlock_exit:
231 	/* unlock parent directory */
232 	vput(a->a_dvp);	/* locked at v7fs_lookup(); */
233 
234 	return error;
235 }
236 
237 int
238 v7fs_mknod(void *v)
239 {
240 	struct vop_mknod_args /* {
241 				 struct vnode		*a_dvp;
242 				 struct vnode		**a_vpp;
243 				 struct componentname	*a_cnp;
244 				 struct vattr		*a_vap;
245 				 } */ *a = v;
246 	struct componentname *cnp = a->a_cnp;
247 	kauth_cred_t cr = cnp->cn_cred;
248 	struct vnode *dvp = a->a_dvp;
249 	struct vattr *va = a->a_vap;
250 	struct v7fs_node *parent_node = dvp->v_data;
251 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
252 	struct v7fs_self *fs = v7fsmount->core;
253 	struct mount *mp = v7fsmount->mountp;
254 	struct v7fs_fileattr attr;
255 
256 	v7fs_ino_t ino;
257 	int error = 0;
258 
259 	DPRINTF("%s %06o %lx %d\n", cnp->cn_nameptr, va->va_mode,
260 	    (long)va->va_rdev, va->va_type);
261 	memset(&attr, 0, sizeof(attr));
262 	attr.uid = kauth_cred_geteuid(cr);
263 	attr.gid = kauth_cred_getegid(cr);
264 	attr.mode = va->va_mode | vtype_to_v7fs_mode(va->va_type);
265 	attr.device = va->va_rdev;
266 
267 	if ((error = v7fs_file_allocate(fs, &parent_node->inode,
268 	    cnp->cn_nameptr, &attr, &ino)))
269 		goto unlock_exit;
270 	/* Sync dirent size change. */
271 	uvm_vnp_setsize(dvp, v7fs_inode_filesize(&parent_node->inode));
272 
273 	if ((error = v7fs_vget(mp, ino, a->a_vpp))) {
274 		DPRINTF("can't get vnode.\n");
275 		goto unlock_exit;
276 	}
277 	struct v7fs_node *newnode = (*a->a_vpp)->v_data;
278 	newnode->update_ctime = true;
279 	newnode->update_mtime = true;
280 	newnode->update_atime = true;
281 
282 unlock_exit:
283 	vput(dvp);
284 
285 	return error;
286 }
287 
288 int
289 v7fs_open(void *v)
290 {
291 	struct vop_open_args /* {
292 				struct vnode *a_vp;
293 				int  a_mode;
294 				kauth_cred_t a_cred;
295 				} */ *a = v;
296 
297 	struct vnode *vp = a->a_vp;
298 	struct v7fs_node *v7node = vp->v_data;
299 	struct v7fs_inode *inode = &v7node->inode;
300 
301 	DPRINTF("inode %d\n", inode->inode_number);
302 	/* Append mode file pointer is managed by kernel. */
303 	if (inode->append_mode &&
304 	    ((a->a_mode & (FWRITE | O_APPEND)) == FWRITE)) {
305 		DPRINTF("file is already opened by append mode.\n");
306 		return EPERM;
307 	}
308 
309 	return 0;
310 }
311 
312 int
313 v7fs_close(void *v)
314 {
315 	struct vop_close_args /* {
316 				 struct vnodeop_desc *a_desc;
317 				 struct vnode *a_vp;
318 				 int  a_fflag;
319 				 kauth_cred_t a_cred;
320 				 } */ *a = v;
321 	struct vnode *vp = a->a_vp;
322 #ifdef V7FS_VNOPS_DEBUG
323 	struct v7fs_node *v7node = vp->v_data;
324 	struct v7fs_inode *inode = &v7node->inode;
325 #endif
326 	DPRINTF("#%d (i)%dbyte (v)%zubyte\n", inode->inode_number,
327 	    v7fs_inode_filesize(inode), vp->v_size);
328 
329 	/* Update timestamp */
330 	v7fs_update(vp, 0, 0, UPDATE_WAIT);
331 
332 	return 0;
333 }
334 
335 static int
336 v7fs_check_possible(struct vnode *vp, struct v7fs_node *v7node,
337     mode_t mode)
338 {
339 
340 	if (!(mode & VWRITE))
341 	  return 0;
342 
343 	switch (vp->v_type) {
344 	default:
345 		/*  special file is always writable. */
346 		return 0;
347 	case VDIR:
348 	case VLNK:
349 	case VREG:
350 		break;
351 	}
352 
353 	return vp->v_mount->mnt_flag & MNT_RDONLY ? EROFS : 0;
354 }
355 
356 static int
357 v7fs_check_permitted(struct vnode *vp, struct v7fs_node *v7node,
358     mode_t mode, kauth_cred_t cred)
359 {
360 
361 	struct v7fs_inode *inode = &v7node->inode;
362 
363 	return genfs_can_access(vp->v_type, inode->mode, inode->uid, inode->gid,
364 	    mode, cred);
365 }
366 
367 int
368 v7fs_access(void *v)
369 {
370 	struct vop_access_args /* {
371 				  struct vnode	*a_vp;
372 				  int		a_mode;
373 				  kauth_cred_t	a_cred;
374 				  } */ *ap = v;
375 	struct vnode *vp = ap->a_vp;
376 	struct v7fs_node *v7node = vp->v_data;
377 	int error;
378 
379 	error = v7fs_check_possible(vp, v7node, ap->a_mode);
380 	if (error)
381 		return error;
382 
383 	error = v7fs_check_permitted(vp, v7node, ap->a_mode, ap->a_cred);
384 
385 	return error;
386 }
387 
388 int
389 v7fs_getattr(void *v)
390 {
391 	struct vop_getattr_args /* {
392 				   struct vnode *a_vp;
393 				   struct vattr *a_vap;
394 				   kauth_cred_t a_cred;
395 				   } */ *ap = v;
396 	struct vnode *vp = ap->a_vp;
397 	struct v7fs_node *v7node = vp->v_data;
398 	struct v7fs_inode *inode = &v7node->inode;
399 	struct v7fs_mount *v7fsmount = v7node->v7fsmount;
400 	struct vattr *vap = ap->a_vap;
401 
402 	DPRINTF("\n");
403 	vap->va_type = vp->v_type;
404 	vap->va_mode = inode->mode;
405 	vap->va_nlink = inode->nlink;
406 	vap->va_uid = inode->uid;
407 	vap->va_gid = inode->gid;
408 	vap->va_fsid = v7fsmount->devvp->v_rdev;
409 	vap->va_fileid = inode->inode_number;
410 	vap->va_size = vp->v_size;
411 	vap->va_atime.tv_sec = inode->atime;
412 	vap->va_mtime.tv_sec = inode->mtime;
413 	vap->va_ctime.tv_sec = inode->ctime;
414 	vap->va_birthtime.tv_sec = 0;
415 	vap->va_gen = 1;
416 	vap->va_flags = 0;
417 	vap->va_rdev = inode->device;
418 	vap->va_bytes = vap->va_size; /* No sparse support. */
419 	vap->va_filerev = 0;
420 	vap->va_vaflags = 0;
421 	/* PAGE_SIZE is larger than sizeof(struct dirent). OK.
422 	   getcwd_scandir()@vfs_getcwd.c */
423 	vap->va_blocksize = PAGE_SIZE;
424 
425 	return 0;
426 }
427 
428 int
429 v7fs_setattr(void *v)
430 {
431 	struct vop_setattr_args /* {
432 				   struct vnode *a_vp;
433 				   struct vattr *a_vap;
434 				   kauth_cred_t a_cred;
435 				   struct proc *p;
436 				   } */ *ap = v;
437 	struct vnode *vp = ap->a_vp;
438 	struct vattr *vap = ap->a_vap;
439 	struct v7fs_node *v7node = vp->v_data;
440 	struct v7fs_self *fs = v7node->v7fsmount->core;
441 	struct v7fs_inode *inode = &v7node->inode;
442 	struct timespec *acc, *mod;
443 	int error = 0;
444 	acc = mod = NULL;
445 
446 	DPRINTF("\n");
447 
448 	if (vp->v_mount->mnt_flag & MNT_RDONLY) {
449 		switch (vp->v_type) {
450 		default:
451 			/*  special file is always writable. */
452 			break;
453 		case VDIR:
454 		case VLNK:
455 		case VREG:
456 			DPRINTF("read-only mount\n");
457 			return EROFS;
458 		}
459 	}
460 
461 	if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
462 	    (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
463 	    (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
464 	    ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
465 		DPRINTF("invalid request\n");
466 		return EINVAL;
467 	}
468 	/* File pointer mode. */
469 	if ((vap->va_flags != VNOVAL) && (vap->va_flags & SF_APPEND)) {
470 		DPRINTF("Set append-mode.\n");
471 		inode->append_mode = true;
472 	}
473 
474 	/* File size change. */
475 	if ((vap->va_size != VNOVAL) && (vp->v_type == VREG)) {
476 		error = v7fs_datablock_size_change(fs, vap->va_size, inode);
477 		if (error == 0)
478 			uvm_vnp_setsize(vp, vap->va_size);
479 	}
480 
481 	if (vap->va_uid != (uid_t)VNOVAL) {
482 		inode->uid = vap->va_uid;
483 	}
484 	if (vap->va_gid != (uid_t)VNOVAL) {
485 		inode->gid = vap->va_gid;
486 	}
487 	if (vap->va_mode != (mode_t)VNOVAL) {
488 		v7fs_inode_chmod(inode, vap->va_mode);
489 	}
490 	if (vap->va_atime.tv_sec != VNOVAL) {
491 		acc = &vap->va_atime;
492 	}
493 	if (vap->va_mtime.tv_sec != VNOVAL) {
494 		mod = &vap->va_mtime;
495 		v7node->update_mtime = true;
496 	}
497 	if (vap->va_ctime.tv_sec != VNOVAL) {
498 		v7node->update_ctime = true;
499 	}
500 
501 	v7node->update_atime = true;
502 	v7fs_update(vp, acc, mod, 0);
503 
504 	return error;
505 }
506 
507 int
508 v7fs_read(void *v)
509 {
510 	struct vop_read_args /* {
511 				struct vnode *a_vp;
512 				struct uio *a_uio;
513 				int a_ioflag;
514 				kauth_cred_t a_cred;
515 				} */ *a = v;
516 	struct vnode *vp = a->a_vp;
517 	struct uio *uio = a->a_uio;
518 	struct v7fs_node *v7node = vp->v_data;
519 	struct v7fs_inode *inode = &v7node->inode;
520 	vsize_t sz, filesz = v7fs_inode_filesize(inode);
521 	const int advice = IO_ADV_DECODE(a->a_ioflag);
522 	int error = 0;
523 
524 	DPRINTF("type=%d inode=%d\n", vp->v_type, v7node->inode.inode_number);
525 
526 	while (uio->uio_resid > 0) {
527 		if ((sz = MIN(filesz - uio->uio_offset, uio->uio_resid)) == 0)
528 			break;
529 
530 		error = ubc_uiomove(&vp->v_uobj, uio, sz, advice, UBC_READ |
531 		    UBC_PARTIALOK | UBC_UNMAP_FLAG(v));
532 		if (error) {
533 			break;
534 		}
535 		DPRINTF("read %zubyte\n", sz);
536 	}
537 	v7node->update_atime = true;
538 
539 	return  error;
540 }
541 
542 int
543 v7fs_write(void *v)
544 {
545 	struct vop_write_args /* {
546 				 struct vnode *a_vp;
547 				 struct uio *a_uio;
548 				 int  a_ioflag;
549 				 kauth_cred_t a_cred;
550 				 } */ *a = v;
551 	struct vnode *vp = a->a_vp;
552 	struct uio *uio = a->a_uio;
553 	int advice = IO_ADV_DECODE(a->a_ioflag);
554 	struct v7fs_node *v7node = vp->v_data;
555 	struct v7fs_inode *inode = &v7node->inode;
556 	struct v7fs_self *fs = v7node->v7fsmount->core;
557 	vsize_t sz;
558 	int error = 0;
559 
560 	if (uio->uio_resid == 0)
561 		return 0;
562 
563 	sz = v7fs_inode_filesize(inode);
564 	DPRINTF("(i)%ld (v)%zu ofs=%zu + res=%zu = %zu\n", sz, vp->v_size,
565 	    uio->uio_offset, uio->uio_resid, uio->uio_offset + uio->uio_resid);
566 
567 	/* Append mode file offset is managed by kernel. */
568 	if (a->a_ioflag & IO_APPEND)
569 		uio->uio_offset = sz;
570 
571 	/* If write region is over filesize, expand. */
572 	size_t newsize= uio->uio_offset + uio->uio_resid;
573 	ssize_t expand = newsize - sz;
574  	if (expand > 0) {
575 		if ((error = v7fs_datablock_expand(fs, inode, expand)))
576 			return error;
577 		uvm_vnp_setsize(vp, newsize);
578 	}
579 
580 	while (uio->uio_resid > 0) {
581 		sz = uio->uio_resid;
582 		if ((error = ubc_uiomove(&vp->v_uobj, uio, sz, advice,
583 			    UBC_WRITE | UBC_UNMAP_FLAG(v))))
584 			break;
585 		DPRINTF("write %zubyte\n", sz);
586 	}
587 	v7node->update_mtime = true;
588 
589 	return error;
590 }
591 
592 int
593 v7fs_fsync(void *v)
594 {
595 	struct vop_fsync_args /* {
596 				 struct vnode *a_vp;
597 				 kauth_cred_t a_cred;
598 				 int a_flags;
599 				 off_t offlo;
600 				 off_t offhi;
601 				 } */ *a = v;
602 	struct vnode *vp = a->a_vp;
603 	int error, wait;
604 
605 	DPRINTF("%p\n", a->a_vp);
606 	if (a->a_flags & FSYNC_CACHE) {
607 		return EOPNOTSUPP;
608 	}
609 
610 	wait = (a->a_flags & FSYNC_WAIT);
611 	error = vflushbuf(vp, wait);
612 
613 	if (error == 0 && (a->a_flags & FSYNC_DATAONLY) == 0)
614 		error = v7fs_update(vp, NULL, NULL, wait ? UPDATE_WAIT : 0);
615 
616 	return error;
617 }
618 
619 int
620 v7fs_remove(void *v)
621 {
622 	struct vop_remove_args /* {
623 				  struct vnodeop_desc *a_desc;
624 				  struct vnode * a_dvp;
625 				  struct vnode * a_vp;
626 				  struct componentname * a_cnp;
627 				  } */ *a = v;
628 	struct v7fs_node *parent_node = a->a_dvp->v_data;
629 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
630 	struct vnode *vp = a->a_vp;
631 	struct v7fs_inode *inode = &((struct v7fs_node *)vp->v_data)->inode;
632 	struct vnode *dvp = a->a_dvp;
633 	struct v7fs_self *fs = v7fsmount->core;
634 	bool remove;
635 	int error = 0;
636 
637 	DPRINTF("delete %s\n", a->a_cnp->cn_nameptr);
638 
639 	if (vp->v_type == VDIR) {
640 		error = EPERM;
641 		goto out;
642 	}
643 
644 	remove = v7fs_inode_nlink(inode) == 1;
645 	if (remove)
646 		uvm_vnp_setsize(vp, 0);
647 
648 	if ((error = v7fs_file_deallocate(fs, &parent_node->inode,
649 		    a->a_cnp->cn_nameptr))) {
650 		DPRINTF("v7fs_file_delete failed.\n");
651 		goto out;
652 	}
653 	/* Sync dirent size change. */
654 	uvm_vnp_setsize(dvp, v7fs_inode_filesize(&parent_node->inode));
655 	/* This inode is no longer used. -> v7fs_inactive */
656 	if (remove)
657 		memset(inode, 0, sizeof(*inode));
658 
659 out:
660 	if (dvp == vp)
661 		vrele(vp); /* v_usecount-- of unlocked vp */
662 	else
663 		vput(vp); /* unlock vp and then v_usecount-- */
664 	vput(dvp);
665 
666 	return error;
667 }
668 
669 int
670 v7fs_link(void *v)
671 {
672 	struct vop_link_args /* {
673 				struct vnode *a_dvp;
674 				struct vnode *a_vp;
675 				struct componentname *a_cnp;
676 				} */ *a = v;
677 	struct vnode *dvp = a->a_dvp;
678 	struct vnode *vp = a->a_vp;
679 	struct v7fs_node *parent_node = dvp->v_data;
680 	struct v7fs_node *node = vp->v_data;
681 	struct v7fs_inode *parent = &parent_node->inode;
682 	struct v7fs_inode *p = &node->inode;
683 	struct v7fs_self *fs = node->v7fsmount->core;
684 	struct componentname *cnp = a->a_cnp;
685 	int error = 0;
686 
687 	DPRINTF("%p\n", vp);
688 	/* Lock soruce file */
689 	if ((error = vn_lock(vp, LK_EXCLUSIVE))) {
690 		DPRINTF("lock failed. %p\n", vp);
691 		VOP_ABORTOP(dvp, cnp);
692 		goto unlock;
693 	}
694 	error = v7fs_file_link(fs, parent, p, cnp->cn_nameptr);
695 	/* Sync dirent size change. */
696 	uvm_vnp_setsize(dvp, v7fs_inode_filesize(&parent_node->inode));
697 
698 	VOP_UNLOCK(vp);
699 unlock:
700 	vput(dvp);
701 
702 	return error;
703 }
704 
705 int
706 v7fs_rename(void *v)
707 {
708 	struct vop_rename_args /* {
709 				  struct vnode *a_fdvp;	from parent-directory
710 				  struct vnode *a_fvp;	from file
711 				  struct componentname *a_fcnp;
712 				  struct vnode *a_tdvp;	to parent-directory
713 				  struct vnode *a_tvp;	to file
714 				  struct componentname *a_tcnp;
715 				  } */ *a = v;
716 	struct vnode *fvp = a->a_fvp;
717 	struct vnode *tvp = a->a_tvp;
718 	struct vnode *fdvp = a->a_fdvp;
719 	struct vnode *tdvp = a->a_tdvp;
720 	struct v7fs_node *parent_from = fdvp->v_data;
721 	struct v7fs_node *parent_to = tdvp->v_data;
722 	struct v7fs_node *v7node = fvp->v_data;
723 	struct v7fs_self *fs = v7node->v7fsmount->core;
724 	const char *from_name = a->a_fcnp->cn_nameptr;
725 	const char *to_name = a->a_tcnp->cn_nameptr;
726 	int error;
727 
728 	DPRINTF("%s->%s\n", from_name, to_name);
729 	/* tvp may be NULL. allocated here. */
730 	if ((fvp->v_mount != tdvp->v_mount) ||
731 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
732 		error = EXDEV;
733 		DPRINTF("cross-device link\n");
734 		goto out;
735 	}
736 	// XXXsource file lock?
737 	error = v7fs_file_rename(fs, &parent_from->inode, from_name,
738 	    &parent_to->inode, to_name);
739 	/* Sync dirent size change. */
740 	uvm_vnp_setsize(tdvp, v7fs_inode_filesize(&parent_to->inode));
741 	uvm_vnp_setsize(fdvp, v7fs_inode_filesize(&parent_from->inode));
742 out:
743 	if (tvp)
744 		vput(tvp);  /* locked on entry */
745 	if (tdvp == tvp)
746 		vrele(tdvp);
747 	else
748 		vput(tdvp);
749 	vrele(fdvp);
750 	vrele(fvp);
751 
752 	return error;
753 }
754 
755 int
756 v7fs_mkdir(void *v)
757 {
758 	struct vop_mkdir_args /* {
759 				 struct vnode		*a_dvp;
760 				 struct vnode		**a_vpp;
761 				 struct componentname	*a_cnp;
762 				 struct vattr		*a_vap;
763 				 } */ *a = v;
764 	struct componentname *cnp = a->a_cnp;
765 	kauth_cred_t cr = cnp->cn_cred;
766 	struct vnode *dvp = a->a_dvp;
767 	struct vattr *va = a->a_vap;
768 	struct v7fs_node *parent_node = dvp->v_data;
769 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
770 	struct v7fs_self *fs = v7fsmount->core;
771 	struct v7fs_fileattr attr;
772 	struct mount *mp = v7fsmount->mountp;
773 	v7fs_ino_t ino;
774 	int error = 0;
775 
776 	DPRINTF("\n");
777 	memset(&attr, 0, sizeof(attr));
778 	attr.uid = kauth_cred_geteuid(cr);
779 	attr.gid = kauth_cred_getegid(cr);
780 	attr.mode = va->va_mode | vtype_to_v7fs_mode(va->va_type);
781 
782 	if ((error = v7fs_file_allocate(fs, &parent_node->inode,
783 	    cnp->cn_nameptr, &attr, &ino)))
784 		goto unlock_exit;
785 	/* Sync dirent size change. */
786 	uvm_vnp_setsize(dvp, v7fs_inode_filesize(&parent_node->inode));
787 
788 	if ((error = v7fs_vget(mp, ino, a->a_vpp))) {
789 		DPRINTF("can't get vnode.\n");
790 	}
791 	struct v7fs_node *newnode = (*a->a_vpp)->v_data;
792 	newnode->update_ctime = true;
793 	newnode->update_mtime = true;
794 	newnode->update_atime = true;
795 
796 unlock_exit:
797 	vput(dvp);
798 
799 	return error;
800 }
801 
802 int
803 v7fs_rmdir(void *v)
804 {
805 	struct vop_rmdir_args /* {
806 				 struct vnode		*a_dvp;
807 				 struct vnode		*a_vp;
808 				 struct componentname	*a_cnp;
809 				 } */ *a = v;
810 	struct vnode *vp = a->a_vp;
811 	struct vnode *dvp = a->a_dvp;
812 	struct v7fs_node *parent_node = dvp->v_data;
813 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
814 	struct v7fs_inode *inode = &((struct v7fs_node *)vp->v_data)->inode;
815 	struct v7fs_self *fs = v7fsmount->core;
816 	int error = 0;
817 
818 	DPRINTF("delete %s\n", a->a_cnp->cn_nameptr);
819 
820 	KDASSERT(vp->v_type == VDIR);
821 
822 	if ((error = v7fs_file_deallocate(fs, &parent_node->inode,
823 	    a->a_cnp->cn_nameptr))) {
824 		DPRINTF("v7fs_directory_deallocate failed.\n");
825 		goto out;
826 	}
827 	uvm_vnp_setsize(vp, 0);
828 	/* Sync dirent size change. */
829 	uvm_vnp_setsize(dvp, v7fs_inode_filesize(&parent_node->inode));
830 	/* This inode is no longer used. -> v7fs_inactive */
831 	memset(inode, 0, sizeof(*inode));
832 out:
833 	vput(vp);
834 	vput(dvp);
835 
836 	return error;
837 }
838 
839 struct v7fs_readdir_arg {
840 	struct dirent *dp;
841 	struct uio *uio;
842 	int start;
843 	int end;
844 	int cnt;
845 };
846 static int readdir_subr(struct v7fs_self *, void *, v7fs_daddr_t, size_t);
847 
848 int
849 readdir_subr(struct v7fs_self *fs, void *ctx, v7fs_daddr_t blk, size_t sz)
850 {
851 	struct v7fs_readdir_arg *p = (struct v7fs_readdir_arg *)ctx;
852 	struct v7fs_dirent *dir;
853 	struct dirent *dp = p->dp;
854 	struct v7fs_inode inode;
855 	char filename[V7FS_NAME_MAX + 1];
856 	int i, n;
857 	int error = 0;
858 	void *buf;
859 
860 	if (!(buf = scratch_read(fs, blk)))
861 		return EIO;
862 	dir = (struct v7fs_dirent *)buf;
863 
864 	n = sz / sizeof(*dir);
865 
866 	for (i = 0; (i < n) && (p->cnt < p->end); i++, dir++, p->cnt++) {
867 		if (p->cnt < p->start)
868 			continue;
869 
870 		if ((error = v7fs_inode_load(fs, &inode, dir->inode_number)))
871 			break;
872 
873 		v7fs_dirent_filename(filename, dir->name);
874 
875 		DPRINTF("inode=%d name=%s %s\n", dir->inode_number, filename,
876 		    v7fs_inode_isdir(&inode) ? "DIR" : "FILE");
877 		memset(dp, 0, sizeof(*dp));
878 		dp->d_fileno = dir->inode_number;
879 		dp->d_type = v7fs_mode_to_d_type(inode.mode);
880 		dp->d_namlen = strlen(filename);
881 		strcpy(dp->d_name, filename);
882 		dp->d_reclen = sizeof(*dp);
883 		if ((error = uiomove(dp, dp->d_reclen, p->uio))) {
884 			DPRINTF("uiomove failed.\n");
885 			break;
886 		}
887 	}
888 	scratch_free(fs, buf);
889 
890 	if (p->cnt == p->end)
891 		return V7FS_ITERATOR_BREAK;
892 
893 	return error;
894 }
895 
896 int
897 v7fs_readdir(void *v)
898 {
899 	struct vop_readdir_args /* {
900 				   struct vnode *a_vp;
901 				   struct uio *a_uio;
902 				   kauth_cred_t a_cred;
903 				   int *a_eofflag;
904 				   off_t **a_cookies;
905 				   int *a_ncookies;
906 				   } */ *a = v;
907 	struct uio *uio = a->a_uio;
908 	struct vnode *vp = a->a_vp;
909 	struct v7fs_node *v7node = vp->v_data;
910 	struct v7fs_inode *inode = &v7node->inode;
911 	struct v7fs_self *fs = v7node->v7fsmount->core;
912 	struct dirent *dp;
913 	int error;
914 
915 	DPRINTF("offset=%zu residue=%zu\n", uio->uio_offset, uio->uio_resid);
916 
917 	KDASSERT(vp->v_type == VDIR);
918 	KDASSERT(uio->uio_offset >= 0);
919 	KDASSERT(v7fs_inode_isdir(inode));
920 
921 	struct v7fs_readdir_arg arg;
922 	arg.start = uio->uio_offset / sizeof(*dp);
923 	arg.end = arg.start +  uio->uio_resid / sizeof(*dp);
924 	if (arg.start == arg.end) {/* user buffer has not enuf space. */
925 		DPRINTF("uio buffer too small\n");
926 		return ENOMEM;
927 	}
928 	dp = malloc(sizeof(*dp), M_V7FS, M_WAITOK | M_ZERO);
929 	arg.cnt = 0;
930 	arg.dp = dp;
931 	arg.uio = uio;
932 
933 	*a->a_eofflag = false;
934 	error = v7fs_datablock_foreach(fs, inode, readdir_subr, &arg);
935 	if (error == V7FS_ITERATOR_END) {
936 		*a->a_eofflag = true;
937 	}
938 	if (error < 0)
939 		error = 0;
940 
941 	free(dp, M_V7FS);
942 
943 	return error;
944 }
945 
946 int
947 v7fs_inactive(void *v)
948 {
949 	struct vop_inactive_args /* {
950 				    struct vnode *a_vp;
951 				    bool *a_recycle;
952 				    } */ *a = v;
953 	struct vnode *vp = a->a_vp;
954 	struct v7fs_node *v7node = vp->v_data;
955 	struct v7fs_inode *inode = &v7node->inode;
956 
957 	DPRINTF("%p\n", vp);
958 
959 	if (v7fs_inode_allocated(inode)) {
960 		v7fs_update(vp, 0, 0, UPDATE_WAIT);
961 	}
962 
963 	*a->a_recycle = true;
964 
965 	VOP_UNLOCK(vp);
966 
967 	return 0;
968 }
969 
970 int
971 v7fs_reclaim(void *v)
972 {
973 	/*This vnode is no longer referenced by kernel. */
974 	extern struct pool v7fs_node_pool;
975 	struct vop_reclaim_args /* {
976 				   struct vnode *a_vp;
977 				   } */ *a = v;
978 	struct vnode *vp = a->a_vp;
979 	struct v7fs_node *v7node = vp->v_data;
980 
981 	DPRINTF("%p\n", vp);
982 	mutex_enter(&mntvnode_lock);
983 	LIST_REMOVE(v7node, link);
984 	mutex_exit(&mntvnode_lock);
985 	genfs_node_destroy(vp);
986 	pool_put(&v7fs_node_pool, v7node);
987 	vp->v_data = NULL;
988 
989 	return 0;
990 }
991 
992 int
993 v7fs_bmap(void *v)
994 {
995 	struct vop_bmap_args /* {
996 				struct vnode *a_vp;
997 				daddr_t  a_bn;
998 				struct vnode **a_vpp;
999 				daddr_t *a_bnp;
1000 				int *a_runp;
1001 				} */ *a = v;
1002 	struct vnode *vp = a->a_vp;
1003 	struct v7fs_node *v7node = vp->v_data;
1004 	struct v7fs_mount *v7fsmount = v7node->v7fsmount;
1005 	struct v7fs_self *fs = v7node->v7fsmount->core;
1006 	struct v7fs_inode *inode = &v7node->inode;
1007 	int error = 0;
1008 
1009 	DPRINTF("inode=%d offset=%zu %p\n", inode->inode_number, a->a_bn, vp);
1010 	DPRINTF("filesize: %d\n", inode->filesize);
1011 	if (!a->a_bnp)
1012 		return 0;
1013 
1014 	v7fs_daddr_t blk;
1015 	if (!(blk = v7fs_datablock_last(fs, inode,
1016 	    (a->a_bn + 1) << V7FS_BSHIFT))) {
1017 		/* +1 converts block # to file offset. */
1018 		return ENOSPC;
1019 	}
1020 
1021 	*a->a_bnp = blk;
1022 
1023 	if (a->a_vpp)
1024 		*a->a_vpp = v7fsmount->devvp;
1025 	if (a->a_runp)
1026 		*a->a_runp = 0; /*XXX TODO */
1027 
1028 	DPRINTF("%d  %zu->%zu status=%d\n", inode->inode_number, a->a_bn,
1029 	    *a->a_bnp, error);
1030 
1031 	return error;
1032 }
1033 
1034 int
1035 v7fs_strategy(void *v)
1036 {
1037 	struct vop_strategy_args /* {
1038 				    struct vnode *a_vp;
1039 				    struct buf *a_bp;
1040 				    } */ *a = v;
1041 	struct buf *b = a->a_bp;
1042 	struct vnode *vp = a->a_vp;
1043 	struct v7fs_node *v7node = vp->v_data;
1044 	struct v7fs_mount *v7fsmount = v7node->v7fsmount;
1045 	int error;
1046 
1047 	DPRINTF("%p\n", vp);
1048 	KDASSERT(vp->v_type == VREG);
1049 	if (b->b_blkno == b->b_lblkno) {
1050 		error = VOP_BMAP(vp, b->b_lblkno, NULL, &b->b_blkno, NULL);
1051 		if (error) {
1052 			b->b_error = error;
1053 			biodone(b);
1054 			return error;
1055 		}
1056 		if ((long)b->b_blkno == -1)
1057 			clrbuf(b);
1058 	}
1059 	if ((long)b->b_blkno == -1) {
1060 		biodone(b);
1061 		return 0;
1062 	}
1063 
1064 	return VOP_STRATEGY(v7fsmount->devvp, b);
1065 }
1066 
1067 int
1068 v7fs_print(void *v)
1069 {
1070 	struct vop_print_args /* {
1071 				 struct vnode *a_vp;
1072 				 } */ *a = v;
1073 	struct v7fs_node *v7node = a->a_vp->v_data;
1074 
1075 	v7fs_inode_dump(&v7node->inode);
1076 
1077 	return 0;
1078 }
1079 
1080 int
1081 v7fs_advlock(void *v)
1082 {
1083 	struct vop_advlock_args /* {
1084 				   struct vnode *a_vp;
1085 				   void *a_id;
1086 				   int a_op;
1087 				   struct flock *a_fl;
1088 				   int a_flags;
1089 				   } */ *a = v;
1090 	struct v7fs_node *v7node = a->a_vp->v_data;
1091 
1092 	DPRINTF("op=%d\n", a->a_op);
1093 
1094 	return lf_advlock(a, &v7node->lockf,
1095 	    v7fs_inode_filesize(&v7node->inode));
1096 }
1097 
1098 int
1099 v7fs_pathconf(void *v)
1100 {
1101 	struct vop_pathconf_args /* {
1102 				    struct vnode *a_vp;
1103 				    int a_name;
1104 				    register_t *a_retval;
1105 				    } */ *a = v;
1106 	int err = 0;
1107 
1108 	DPRINTF("%p\n", a->a_vp);
1109 
1110 	switch (a->a_name) {
1111 	case _PC_LINK_MAX:
1112 		*a->a_retval = V7FS_LINK_MAX;
1113 		break;
1114 	case _PC_NAME_MAX:
1115 		*a->a_retval = V7FS_NAME_MAX;
1116 		break;
1117 	case _PC_PATH_MAX:
1118 		*a->a_retval = V7FS_PATH_MAX;
1119 		break;
1120 	case _PC_CHOWN_RESTRICTED:
1121 		*a->a_retval = 1;
1122 		break;
1123 	case _PC_NO_TRUNC:
1124 		*a->a_retval = 0;
1125 		break;
1126 	case _PC_SYNC_IO:
1127 		*a->a_retval = 1;
1128 		break;
1129 	case _PC_FILESIZEBITS:
1130 		*a->a_retval = 30; /* ~1G */
1131 		break;
1132 	case _PC_SYMLINK_MAX:
1133 		*a->a_retval = V7FSBSD_MAXSYMLINKLEN;
1134 		break;
1135 	case _PC_2_SYMLINKS:
1136 		*a->a_retval = 1;
1137 		break;
1138 	default:
1139 		err = EINVAL;
1140 		break;
1141 	}
1142 
1143 	return err;
1144 }
1145 
1146 int
1147 v7fs_update(struct vnode *vp, const struct timespec *acc,
1148     const struct timespec *mod, int flags)
1149 {
1150 	struct v7fs_node *v7node = vp->v_data;
1151 	struct v7fs_inode *inode = &v7node->inode;
1152 	struct v7fs_self *fs = v7node->v7fsmount->core;
1153 	bool update = false;
1154 
1155 	DPRINTF("%p %zu %d\n", vp, vp->v_size, v7fs_inode_filesize(inode));
1156 	KDASSERT(vp->v_size == v7fs_inode_filesize(inode));
1157 
1158 	if (v7node->update_atime) {
1159 		inode->atime = acc ? acc->tv_sec : time_second;
1160 		v7node->update_atime = false;
1161 		update = true;
1162 	}
1163 	if (v7node->update_ctime) {
1164 		inode->ctime = time_second;
1165 		v7node->update_ctime = false;
1166 		update = true;
1167 	}
1168 	if (v7node->update_mtime) {
1169 		inode->mtime = mod ? mod->tv_sec : time_second;
1170 		v7node->update_mtime = false;
1171 		update = true;
1172 	}
1173 
1174 	if (update)
1175 		v7fs_inode_writeback(fs, inode);
1176 
1177 	return 0;
1178 }
1179 
1180 int
1181 v7fs_symlink(void *v)
1182 {
1183 	struct vop_symlink_args /* {
1184 				   struct vnode		*a_dvp;
1185 				   struct vnode		**a_vpp;
1186 				   struct componentname	*a_cnp;
1187 				   struct vattr		*a_vap;
1188 				   char			*a_target;
1189 				   } */ *a = v;
1190 	struct v7fs_node *parent_node = a->a_dvp->v_data;
1191 	struct v7fs_mount *v7fsmount = parent_node->v7fsmount;
1192 	struct v7fs_self *fs = v7fsmount->core;
1193 	struct vattr *va = a->a_vap;
1194 	kauth_cred_t cr = a->a_cnp->cn_cred;
1195 	struct componentname *cnp = a->a_cnp;
1196 	struct v7fs_fileattr attr;
1197 	v7fs_ino_t ino;
1198 	const char *from = a->a_target;
1199 	const char *to = cnp->cn_nameptr;
1200 	size_t len = strlen(from) + 1;
1201 	int error = 0;
1202 
1203 	if (len > V7FS_BSIZE) { /* limited to 512byte pathname */
1204 		DPRINTF("too long pathname.");
1205 		return ENAMETOOLONG;
1206 	}
1207 
1208 	memset(&attr, 0, sizeof(attr));
1209 	attr.uid = kauth_cred_geteuid(cr);
1210 	attr.gid = kauth_cred_getegid(cr);
1211 	attr.mode = va->va_mode | vtype_to_v7fs_mode(va->va_type);
1212 
1213 	if ((error = v7fs_file_allocate
1214 		(fs, &parent_node->inode, to, &attr, &ino))) {
1215 		goto unlock_exit;
1216 	}
1217 	/* Sync dirent size change. */
1218 	uvm_vnp_setsize(a->a_dvp, v7fs_inode_filesize(&parent_node->inode));
1219 
1220 	/* Get myself vnode. */
1221 	if ((error = v7fs_vget(v7fsmount->mountp, ino, a->a_vpp))) {
1222 		DPRINTF("can't get vnode.\n");
1223 	}
1224 
1225 	struct v7fs_node *newnode = (*a->a_vpp)->v_data;
1226 	struct v7fs_inode *p = &newnode->inode;
1227 	v7fs_file_symlink(fs, p, from);
1228 	uvm_vnp_setsize(*a->a_vpp, v7fs_inode_filesize(p));
1229 
1230 	newnode->update_ctime = true;
1231 	newnode->update_mtime = true;
1232 	newnode->update_atime = true;
1233 unlock_exit:
1234 	/* unlock parent directory */
1235 	vput(a->a_dvp);
1236 
1237 	return error;
1238 }
1239 
1240 int
1241 v7fs_readlink(void *v)
1242 {
1243 	struct vop_readlink_args /* {
1244 				    struct vnode	*a_vp;
1245 				    struct uio		*a_uio;
1246 				    kauth_cred_t	a_cred;
1247 				    } */ *a = v;
1248 	struct uio *uio = a->a_uio;
1249 	struct vnode *vp = a->a_vp;
1250 	struct v7fs_node *v7node = vp->v_data;
1251 	struct v7fs_inode *inode = &v7node->inode;
1252 	struct v7fs_self *fs = v7node->v7fsmount->core;
1253 	int error = 0;
1254 
1255 	KDASSERT(vp->v_type == VLNK);
1256 	KDASSERT(uio->uio_offset >= 0);
1257 	KDASSERT(v7fs_inode_islnk(inode));
1258 
1259 	v7fs_daddr_t blk = inode->addr[0];
1260 	void *buf;
1261 	if (!(buf = scratch_read(fs, blk))) {
1262 		error = EIO;
1263 		goto error_exit;
1264 	}
1265 
1266 	if ((error = uiomove(buf, strlen(buf), uio))) {
1267 		DPRINTF("uiomove failed.\n");
1268 	}
1269 	scratch_free(fs, buf);
1270 
1271 error_exit:
1272 	return error;
1273 }
1274 
1275 
1276