xref: /illumos-gate/usr/src/uts/common/fs/nfs/nfs4_srv_readdir.c (revision 9fb67ea305c66b6a297583b9b0db6796b0dfe497)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/param.h>
27 #include <sys/types.h>
28 #include <sys/systm.h>
29 #include <sys/cred.h>
30 #include <sys/buf.h>
31 #include <sys/vfs.h>
32 #include <sys/vnode.h>
33 #include <sys/uio.h>
34 #include <sys/errno.h>
35 #include <sys/sysmacros.h>
36 #include <sys/statvfs.h>
37 #include <sys/kmem.h>
38 #include <sys/dirent.h>
39 #include <rpc/types.h>
40 #include <rpc/auth.h>
41 #include <rpc/rpcsec_gss.h>
42 #include <rpc/svc.h>
43 #include <sys/strsubr.h>
44 #include <sys/strsun.h>
45 #include <sys/sdt.h>
46 
47 #include <nfs/nfs.h>
48 #include <nfs/export.h>
49 #include <nfs/nfs4.h>
50 #include <nfs/nfs_cmd.h>
51 
52 
53 /*
54  * RFS4_MINLEN_ENTRY4: XDR-encoded size of smallest possible dirent.
55  *	This is used to return NFS4ERR_TOOSMALL when clients specify
56  *	maxcount that isn't large enough to hold the smallest possible
57  *	XDR encoded dirent.
58  *
59  *	    sizeof cookie (8 bytes) +
60  *	    sizeof name_len (4 bytes) +
61  *	    sizeof smallest (padded) name (4 bytes) +
62  *	    sizeof bitmap4_len (12 bytes) +   NOTE: we always encode len=2 bm4
63  *	    sizeof attrlist4_len (4 bytes) +
64  *	    sizeof next boolean (4 bytes)
65  *
66  * RFS4_MINLEN_RDDIR4: XDR-encoded size of READDIR op reply containing
67  * the smallest possible entry4 (assumes no attrs requested).
68  *	sizeof nfsstat4 (4 bytes) +
69  *	sizeof verifier4 (8 bytes) +
70  *	sizeof entsecond_to_ry4list bool (4 bytes) +
71  *	sizeof entry4 	(36 bytes) +
72  *	sizeof eof bool  (4 bytes)
73  *
74  * RFS4_MINLEN_RDDIR_BUF: minimum length of buffer server will provide to
75  *	VOP_READDIR.  Its value is the size of the maximum possible dirent
76  *	for solaris.  The DIRENT64_RECLEN macro returns	the size of dirent
77  *	required for a given name length.  MAXNAMELEN is the maximum
78  *	filename length allowed in Solaris.  The first two DIRENT64_RECLEN()
79  *	macros are to allow for . and .. entries -- just a minor tweak to try
80  *	and guarantee that buffer we give to VOP_READDIR will be large enough
81  *	to hold ., .., and the largest possible solaris dirent64.
82  */
83 #define	RFS4_MINLEN_ENTRY4 36
84 #define	RFS4_MINLEN_RDDIR4 (4 + NFS4_VERIFIER_SIZE + 4 + RFS4_MINLEN_ENTRY4 + 4)
85 #define	RFS4_MINLEN_RDDIR_BUF \
86 	(DIRENT64_RECLEN(1) + DIRENT64_RECLEN(2) + DIRENT64_RECLEN(MAXNAMELEN))
87 
88 
89 #ifdef	nextdp
90 #undef nextdp
91 #endif
92 #define	nextdp(dp)	((struct dirent64 *)((char *)(dp) + (dp)->d_reclen))
93 
94 verifier4	Readdir4verf = 0x0;
95 
96 static nfs_ftype4 vt_to_nf4[] = {
97 	0, NF4REG, NF4DIR, NF4BLK, NF4CHR, NF4LNK, NF4FIFO, 0, 0, NF4SOCK, 0
98 };
99 
100 int
101 nfs4_readdir_getvp(vnode_t *dvp, char *d_name, vnode_t **vpp,
102 		struct exportinfo **exi, struct svc_req *req,
103 		struct compound_state *cs, int expseudo)
104 {
105 	int error;
106 	int ismntpt;
107 	fid_t fid;
108 	vnode_t *vp, *pre_tvp;
109 	nfsstat4 status;
110 	struct exportinfo *newexi, *saveexi;
111 	cred_t *scr;
112 
113 	*vpp = vp = NULL;
114 
115 	if (error = VOP_LOOKUP(dvp, d_name, &vp, NULL, 0, NULL, cs->cr,
116 	    NULL, NULL, NULL))
117 		return (error);
118 
119 	/*
120 	 * If the directory is a referral point, don't return the
121 	 * attrs, instead set rdattr_error to MOVED.
122 	 */
123 	if (vn_is_nfs_reparse(vp, cs->cr) && !client_is_downrev(req)) {
124 		VN_RELE(vp);
125 		DTRACE_PROBE2(nfs4serv__func__referral__moved,
126 		    vnode_t *, vp, char *, "nfs4_readdir_getvp");
127 		return (NFS4ERR_MOVED);
128 	}
129 
130 	/* Is this object mounted upon? */
131 	ismntpt = vn_ismntpt(vp);
132 
133 	/*
134 	 * Nothing more to do if object is not a mount point or
135 	 * a possible LOFS shadow of an LOFS mount (which won't
136 	 * have v_vfsmountedhere set)
137 	 */
138 	if (ismntpt == 0 && dvp->v_vfsp == vp->v_vfsp && expseudo == 0) {
139 		*vpp = vp;
140 		return (0);
141 	}
142 
143 	if (ismntpt) {
144 		/*
145 		 * Something is mounted here. Traverse and manage the
146 		 * namespace
147 		 */
148 		pre_tvp = vp;
149 		VN_HOLD(pre_tvp);
150 
151 		if ((error = traverse(&vp)) != 0) {
152 			VN_RELE(pre_tvp);
153 			return (error);
154 		}
155 		if (vn_is_nfs_reparse(vp, cs->cr)) {
156 			VN_RELE(vp);
157 			VN_RELE(pre_tvp);
158 			DTRACE_PROBE2(nfs4serv__func__referral__moved,
159 			    vnode_t *, vp, char *, "nfs4_readdir_getvp");
160 			return (NFS4ERR_MOVED);
161 		}
162 	}
163 
164 	bzero(&fid, sizeof (fid));
165 	fid.fid_len = MAXFIDSZ;
166 
167 	/*
168 	 * If VOP_FID not supported by underlying fs (mntfs, procfs,
169 	 * etc.), then return attrs for stub instead of VROOT object.
170 	 * If it fails for any other reason, then return the error.
171 	 */
172 	if (error = VOP_FID(vp, &fid, NULL)) {
173 		if (ismntpt == 0) {
174 			VN_RELE(vp);
175 			return (error);
176 		}
177 
178 		if (error != ENOSYS && error != ENOTSUP) {
179 			VN_RELE(vp);
180 			VN_RELE(pre_tvp);
181 			return (error);
182 		}
183 		/* go back to vnode that is "under" mount */
184 		VN_RELE(vp);
185 		*vpp = pre_tvp;
186 		return (0);
187 	}
188 
189 	newexi = checkexport4(&vp->v_vfsp->vfs_fsid, &fid, vp);
190 	if (newexi == NULL) {
191 		if (ismntpt == 0) {
192 			*vpp = vp;
193 		} else {
194 			VN_RELE(vp);
195 			*vpp = pre_tvp;
196 		}
197 		return (0);
198 	}
199 
200 	if (ismntpt)
201 		VN_RELE(pre_tvp);
202 
203 	/* Save the exi and present the new one to checkauth4() */
204 	saveexi = cs->exi;
205 	cs->exi = newexi;
206 
207 	/* Get the right cred like lookup does */
208 	scr = cs->cr;
209 	cs->cr = crdup(cs->basecr);
210 
211 	status = call_checkauth4(cs, req);
212 
213 	crfree(cs->cr);
214 	cs->cr = scr;
215 	cs->exi = saveexi;
216 
217 	/* Reset what call_checkauth4() may have set */
218 	*cs->statusp = NFS4_OK;
219 
220 	if (status != NFS4_OK) {
221 		VN_RELE(vp);
222 		if (status == NFS4ERR_DELAY)
223 			status = NFS4ERR_ACCESS;
224 		return (status);
225 	}
226 	*vpp = vp;
227 	*exi = newexi;
228 
229 	return (0);
230 }
231 
232 /* This is the set of pathconf data for vfs */
233 typedef struct {
234 	uint64_t maxfilesize;
235 	uint32_t maxlink;
236 	uint32_t maxname;
237 } rfs4_pc_encode_t;
238 
239 
240 static int
241 rfs4_get_pc_encode(vnode_t *vp, rfs4_pc_encode_t *pce, bitmap4 ar, cred_t *cr)
242 {
243 	int error;
244 	ulong_t pc_val;
245 
246 	pce->maxfilesize = 0;
247 	pce->maxlink = 0;
248 	pce->maxname = 0;
249 
250 	if (ar & FATTR4_MAXFILESIZE_MASK) {
251 		/* Maximum File Size */
252 		error = VOP_PATHCONF(vp, _PC_FILESIZEBITS, &pc_val, cr, NULL);
253 		if (error)
254 			return (error);
255 
256 		/*
257 		 * If the underlying file system does not support
258 		 * _PC_FILESIZEBITS, return a reasonable default. Note that
259 		 * error code on VOP_PATHCONF will be 0, even if the underlying
260 		 * file system does not support _PC_FILESIZEBITS.
261 		 */
262 		if (pc_val == (ulong_t)-1) {
263 			pce->maxfilesize = MAXOFF32_T;
264 		} else {
265 			if (pc_val >= (sizeof (uint64_t) * 8))
266 				pce->maxfilesize = INT64_MAX;
267 			else
268 				pce->maxfilesize = ((1LL << (pc_val - 1)) - 1);
269 		}
270 	}
271 
272 	if (ar & FATTR4_MAXLINK_MASK) {
273 		/* Maximum Link Count */
274 		error = VOP_PATHCONF(vp, _PC_LINK_MAX, &pc_val, cr, NULL);
275 		if (error)
276 			return (error);
277 
278 		pce->maxlink = pc_val;
279 	}
280 
281 	if (ar & FATTR4_MAXNAME_MASK) {
282 		/* Maximum Name Length */
283 		error = VOP_PATHCONF(vp, _PC_NAME_MAX, &pc_val, cr, NULL);
284 		if (error)
285 			return (error);
286 
287 		pce->maxname = pc_val;
288 	}
289 
290 	return (0);
291 }
292 
293 /* This is the set of statvfs data that is ready for encoding */
294 typedef struct {
295 	uint64_t space_avail;
296 	uint64_t space_free;
297 	uint64_t space_total;
298 	u_longlong_t fa;
299 	u_longlong_t ff;
300 	u_longlong_t ft;
301 } rfs4_sb_encode_t;
302 
303 static int
304 rfs4_get_sb_encode(vfs_t *vfsp, rfs4_sb_encode_t *psbe)
305 {
306 	int error;
307 	struct statvfs64 sb;
308 
309 	/* Grab the per filesystem info */
310 	if (error = VFS_STATVFS(vfsp, &sb)) {
311 		return (error);
312 	}
313 
314 	/* Calculate space available */
315 	if (sb.f_bavail != (fsblkcnt64_t)-1) {
316 		psbe->space_avail =
317 		    (fattr4_space_avail) sb.f_frsize *
318 		    (fattr4_space_avail) sb.f_bavail;
319 	} else {
320 		psbe->space_avail =
321 		    (fattr4_space_avail) sb.f_bavail;
322 	}
323 
324 	/* Calculate space free */
325 	if (sb.f_bfree != (fsblkcnt64_t)-1) {
326 		psbe->space_free =
327 		    (fattr4_space_free) sb.f_frsize *
328 		    (fattr4_space_free) sb.f_bfree;
329 	} else {
330 		psbe->space_free =
331 		    (fattr4_space_free) sb.f_bfree;
332 	}
333 
334 	/* Calculate space total */
335 	if (sb.f_blocks != (fsblkcnt64_t)-1) {
336 		psbe->space_total =
337 		    (fattr4_space_total) sb.f_frsize *
338 		    (fattr4_space_total) sb.f_blocks;
339 	} else {
340 		psbe->space_total =
341 		    (fattr4_space_total) sb.f_blocks;
342 	}
343 
344 	/* For use later on attr encode */
345 	psbe->fa = sb.f_favail;
346 	psbe->ff = sb.f_ffree;
347 	psbe->ft = sb.f_files;
348 
349 	return (0);
350 }
351 
352 /*
353  * Macros to handle if we have don't have enough space for the requested
354  * attributes and this is the first entry and the
355  * requested attributes are more than the minimal useful
356  * set, reset the attributes to the minimal set and
357  * retry the encoding. If the client has asked for both
358  * mounted_on_fileid and fileid, prefer mounted_on_fileid.
359  */
360 #define	MINIMAL_RD_ATTRS						\
361 	(FATTR4_MOUNTED_ON_FILEID_MASK|					\
362 	FATTR4_FILEID_MASK|						\
363 	FATTR4_RDATTR_ERROR_MASK)
364 
365 #define	MINIMIZE_ATTR_MASK(m) {						\
366 	if ((m) & FATTR4_MOUNTED_ON_FILEID_MASK)			\
367 	    (m) &= FATTR4_RDATTR_ERROR_MASK|FATTR4_MOUNTED_ON_FILEID_MASK;\
368 	else								\
369 	    (m) &= FATTR4_RDATTR_ERROR_MASK|FATTR4_FILEID_MASK;		\
370 }
371 
372 #define	IS_MIN_ATTR_MASK(m)	(((m) & ~MINIMAL_RD_ATTRS) == 0)
373 /*
374  * If readdir only needs to return FILEID, we can take it from the
375  * dirent struct and save doing the lookup.
376  */
377 /* ARGSUSED */
378 void
379 rfs4_op_readdir(nfs_argop4 *argop, nfs_resop4 *resop,
380 	struct svc_req *req, struct compound_state *cs)
381 {
382 	READDIR4args *args = &argop->nfs_argop4_u.opreaddir;
383 	READDIR4res *resp = &resop->nfs_resop4_u.opreaddir;
384 	struct exportinfo *newexi = NULL;
385 	int error;
386 	mblk_t *mp;
387 	uint_t mpcount;
388 	int alloc_err = 0;
389 	vnode_t *dvp = cs->vp;
390 	vnode_t *vp;
391 	vattr_t va;
392 	struct dirent64 *dp;
393 	rfs4_sb_encode_t dsbe, sbe;
394 	int vfs_different;
395 	int rddir_data_len, rddir_result_size;
396 	caddr_t rddir_data;
397 	offset_t rddir_next_offset;
398 	int dircount;
399 	int no_space;
400 	int iseofdir;
401 	uint_t eof;
402 	struct iovec iov;
403 	struct uio uio;
404 	int tsize;
405 	int check_visible;
406 	int expseudo = 0;
407 
408 	uint32_t *ptr, *ptr_redzone;
409 	uint32_t *beginning_ptr;
410 	uint32_t *lastentry_ptr;
411 	uint32_t *attrmask_ptr;
412 	uint32_t *attr_offset_ptr;
413 	uint32_t attr_length;
414 	uint32_t rndup;
415 	uint32_t namelen;
416 	uint32_t rddirattr_error = 0;
417 	int nents;
418 	bitmap4 ar = args->attr_request & NFS4_SRV_RDDIR_SUPPORTED_ATTRS;
419 	bitmap4 ae;
420 	rfs4_pc_encode_t dpce, pce;
421 	ulong_t pc_val;
422 	uint64_t maxread;
423 	uint64_t maxwrite;
424 	uint_t true = TRUE;
425 	uint_t false = FALSE;
426 	uid_t lastuid;
427 	gid_t lastgid;
428 	int lu_set, lg_set;
429 	utf8string owner, group;
430 	int owner_error, group_error;
431 	struct sockaddr *ca;
432 	char *name = NULL;
433 
434 	DTRACE_NFSV4_2(op__readdir__start, struct compound_state *, cs,
435 	    READDIR4args *, args);
436 
437 	lu_set = lg_set = 0;
438 	owner.utf8string_len = group.utf8string_len = 0;
439 	owner.utf8string_val = group.utf8string_val = NULL;
440 
441 	resp->mblk = NULL;
442 
443 	/* Maximum read and write size */
444 	maxread = maxwrite = rfs4_tsize(req);
445 
446 	if (dvp == NULL) {
447 		*cs->statusp = resp->status = NFS4ERR_NOFILEHANDLE;
448 		goto out;
449 	}
450 
451 	/*
452 	 * If there is an unshared filesystem mounted on this vnode,
453 	 * do not allow readdir in this directory.
454 	 */
455 	if (vn_ismntpt(dvp)) {
456 		*cs->statusp = resp->status = NFS4ERR_ACCESS;
457 		goto out;
458 	}
459 
460 	if (dvp->v_type != VDIR) {
461 		*cs->statusp = resp->status = NFS4ERR_NOTDIR;
462 		goto out;
463 	}
464 
465 	if (args->maxcount <= RFS4_MINLEN_RDDIR4) {
466 		*cs->statusp = resp->status = NFS4ERR_TOOSMALL;
467 		goto out;
468 	}
469 
470 	/*
471 	 * If write-only attrs are requested, then fail the readdir op
472 	 */
473 	if (args->attr_request &
474 	    (FATTR4_TIME_MODIFY_SET_MASK | FATTR4_TIME_ACCESS_SET_MASK)) {
475 		*cs->statusp = resp->status = NFS4ERR_INVAL;
476 		goto out;
477 	}
478 
479 	error = VOP_ACCESS(dvp, VREAD, 0, cs->cr, NULL);
480 	if (error) {
481 		*cs->statusp = resp->status = puterrno4(error);
482 		goto out;
483 	}
484 
485 	if (args->cookieverf != Readdir4verf) {
486 		*cs->statusp = resp->status = NFS4ERR_NOT_SAME;
487 		goto out;
488 	}
489 
490 	/* Is there pseudo-fs work that is needed for this readdir? */
491 	check_visible = PSEUDO(cs->exi) ||
492 	    ! is_exported_sec(cs->nfsflavor, cs->exi) ||
493 	    cs->access & CS_ACCESS_LIMITED;
494 
495 	/* Check the requested attributes and only do the work if needed */
496 
497 	if (ar & (FATTR4_MAXFILESIZE_MASK |
498 	    FATTR4_MAXLINK_MASK |
499 	    FATTR4_MAXNAME_MASK)) {
500 		if (error = rfs4_get_pc_encode(cs->vp, &dpce, ar, cs->cr)) {
501 			*cs->statusp = resp->status = puterrno4(error);
502 			goto out;
503 		}
504 		pce = dpce;
505 	}
506 
507 	/* If there is statvfs data requested, pick it up once */
508 	if (ar &
509 	    (FATTR4_FILES_AVAIL_MASK |
510 	    FATTR4_FILES_FREE_MASK |
511 	    FATTR4_FILES_TOTAL_MASK |
512 	    FATTR4_FILES_AVAIL_MASK |
513 	    FATTR4_FILES_FREE_MASK |
514 	    FATTR4_FILES_TOTAL_MASK)) {
515 		if (error = rfs4_get_sb_encode(dvp->v_vfsp, &dsbe)) {
516 			*cs->statusp = resp->status = puterrno4(error);
517 			goto out;
518 		}
519 		sbe = dsbe;
520 	}
521 
522 	/*
523 	 * Max transfer size of the server is the absolute limite.
524 	 * If the client has decided to max out with something really
525 	 * tiny, then return toosmall.  Otherwise, move forward and
526 	 * see if a single entry can be encoded.
527 	 */
528 	tsize = rfs4_tsize(req);
529 	if (args->maxcount > tsize)
530 		args->maxcount = tsize;
531 	else if (args->maxcount < RFS4_MINLEN_RDDIR_BUF) {
532 		if (args->maxcount < RFS4_MINLEN_ENTRY4) {
533 			*cs->statusp = resp->status = NFS4ERR_TOOSMALL;
534 			goto out;
535 		}
536 	}
537 
538 	/*
539 	 * How large should the mblk be for outgoing encoding.
540 	 */
541 	if (args->maxcount < MAXBSIZE)
542 		mpcount = MAXBSIZE;
543 	else
544 		mpcount = args->maxcount;
545 
546 	/*
547 	 * mp will contain the data to be sent out in the readdir reply.
548 	 * It will be freed after the reply has been sent.
549 	 * Let's roundup the data to a BYTES_PER_XDR_UNIX multiple,
550 	 * so that the call to xdrmblk_putmblk() never fails.
551 	 */
552 	mp = allocb(RNDUP(mpcount), BPRI_MED);
553 
554 	if (mp == NULL) {
555 		/*
556 		 * The allocation of the client's requested size has
557 		 * failed.  It may be that the size is too large for
558 		 * current system utilization; step down to a "common"
559 		 * size and wait for the allocation to occur.
560 		 */
561 		if (mpcount > MAXBSIZE)
562 			args->maxcount = mpcount = MAXBSIZE;
563 		mp = allocb_wait(RNDUP(mpcount), BPRI_MED,
564 		    STR_NOSIG, &alloc_err);
565 	}
566 
567 	ASSERT(mp != NULL);
568 	ASSERT(alloc_err == 0);
569 
570 	resp->mblk = mp;
571 
572 	ptr = beginning_ptr = (uint32_t *)mp->b_datap->db_base;
573 
574 	/*
575 	 * The "redzone" at the end of the encoding buffer is used
576 	 * to deal with xdr encoding length.  Instead of checking
577 	 * each encoding of an attribute value before it is done,
578 	 * make the assumption that it will fit into the buffer and
579 	 * check occasionally.
580 	 *
581 	 * The largest block of attributes that are encoded without
582 	 * checking the redzone is 18 * BYTES_PER_XDR_UNIT (72 bytes)
583 	 * "round" to 128 as the redzone size.
584 	 */
585 	if (args->maxcount < (mpcount - 128))
586 		ptr_redzone =
587 		    (uint32_t *)(((char *)ptr) + RNDUP(args->maxcount));
588 	else
589 		ptr_redzone =
590 		    (uint32_t *)((((char *)ptr) + RNDUP(mpcount)) - 128);
591 
592 	/*
593 	 * Set the dircount; this will be used as the size for the
594 	 * readdir of the underlying filesystem.  First make sure
595 	 * that it is large enough to do a reasonable readdir (client
596 	 * may have short changed us - it is an advisory number);
597 	 * then make sure that it isn't too large.
598 	 * After all of that, if maxcount is "small" then just use
599 	 * that for the dircount number.
600 	 */
601 	dircount = (args->dircount < MAXBSIZE) ? MAXBSIZE : args->dircount;
602 	dircount = (dircount > tsize) ? tsize : dircount;
603 	if (dircount > args->maxcount)
604 		dircount = args->maxcount;
605 	if (args->maxcount <= MAXBSIZE) {
606 		if (args->maxcount < RFS4_MINLEN_RDDIR_BUF)
607 			dircount = RFS4_MINLEN_RDDIR_BUF;
608 		else
609 			dircount = args->maxcount;
610 	}
611 
612 	/* number of entries fully encoded in outgoing buffer */
613 	nents = 0;
614 
615 	/* ENCODE READDIR4res.cookieverf */
616 	IXDR_PUT_HYPER(ptr, Readdir4verf);
617 
618 	rddir_data_len = dircount;
619 	rddir_data = kmem_alloc(rddir_data_len, KM_NOSLEEP);
620 	if (rddir_data == NULL) {
621 		/* The allocation failed; downsize and wait for it this time */
622 		if (rddir_data_len > MAXBSIZE)
623 			rddir_data_len = dircount = MAXBSIZE;
624 		rddir_data = kmem_alloc(rddir_data_len, KM_SLEEP);
625 	}
626 
627 	rddir_next_offset = (offset_t)args->cookie;
628 
629 	ca = (struct sockaddr *)svc_getrpccaller(req->rq_xprt)->buf;
630 
631 readagain:
632 
633 	no_space = FALSE;
634 	iseofdir = FALSE;
635 
636 	vp = NULL;
637 
638 	/* Move on to reading the directory contents */
639 	iov.iov_base = rddir_data;
640 	iov.iov_len = rddir_data_len;
641 	uio.uio_iov = &iov;
642 	uio.uio_iovcnt = 1;
643 	uio.uio_segflg = UIO_SYSSPACE;
644 	uio.uio_extflg = UIO_COPY_CACHED;
645 	uio.uio_loffset = rddir_next_offset;
646 	uio.uio_resid = rddir_data_len;
647 
648 	(void) VOP_RWLOCK(dvp, V_WRITELOCK_FALSE, NULL);
649 
650 	error = VOP_READDIR(dvp, &uio, cs->cr, &iseofdir, NULL, 0);
651 
652 	VOP_RWUNLOCK(dvp, V_WRITELOCK_FALSE, NULL);
653 
654 	if (error) {
655 		kmem_free((caddr_t)rddir_data, rddir_data_len);
656 		freeb(resp->mblk);
657 		resp->mblk = NULL;
658 		resp->data_len = 0;
659 		*cs->statusp = resp->status = puterrno4(error);
660 		goto out;
661 	}
662 
663 
664 	rddir_result_size = rddir_data_len - uio.uio_resid;
665 
666 	/* No data were read. Check if we reached the end of the directory. */
667 	if (rddir_result_size == 0) {
668 		/* encode the BOOLEAN marking no further entries */
669 		IXDR_PUT_U_INT32(ptr, false);
670 		/* encode the BOOLEAN signifying end of directory */
671 		IXDR_PUT_U_INT32(ptr, iseofdir ? true : false);
672 		resp->data_len = (char *)ptr - (char *)beginning_ptr;
673 		resp->mblk->b_wptr += resp->data_len;
674 		kmem_free((caddr_t)rddir_data, rddir_data_len);
675 		*cs->statusp = resp->status = NFS4_OK;
676 		goto out;
677 	}
678 
679 	lastentry_ptr = ptr;
680 	no_space = 0;
681 	for (dp = (struct dirent64 *)rddir_data;
682 	    !no_space && rddir_result_size > 0; dp = nextdp(dp)) {
683 
684 		/* reset expseudo */
685 		expseudo = 0;
686 
687 		if (vp) {
688 			VN_RELE(vp);
689 			vp = NULL;
690 		}
691 
692 		if (newexi)
693 			newexi = NULL;
694 
695 		rddir_result_size -= dp->d_reclen;
696 
697 		/* skip "." and ".." entries */
698 		if (dp->d_ino == 0 || NFS_IS_DOTNAME(dp->d_name)) {
699 			rddir_next_offset = dp->d_off;
700 			continue;
701 		}
702 
703 		if (check_visible &&
704 		    !nfs_visible_inode(cs->exi, dp->d_ino, &expseudo)) {
705 			rddir_next_offset = dp->d_off;
706 			continue;
707 		}
708 
709 		/*
710 		 * Only if the client requested attributes...
711 		 * If the VOP_LOOKUP fails ENOENT, then skip this entry
712 		 * for the readdir response.  If there was another error,
713 		 * then set the rddirattr_error and the error will be
714 		 * encoded later in the "attributes" section.
715 		 */
716 		ae = ar;
717 		if (ar == 0)
718 			goto reencode_attrs;
719 
720 		error = nfs4_readdir_getvp(dvp, dp->d_name,
721 		    &vp, &newexi, req, cs, expseudo);
722 		if (error == ENOENT) {
723 			rddir_next_offset = dp->d_off;
724 			continue;
725 		}
726 
727 		rddirattr_error = error;
728 
729 		/*
730 		 * The vp obtained from above may be from a
731 		 * different filesystem mount and the vfs-like
732 		 * attributes should be obtained from that
733 		 * different vfs; only do this if appropriate.
734 		 */
735 		if (vp &&
736 		    (vfs_different = (dvp->v_vfsp != vp->v_vfsp))) {
737 			if (ar & (FATTR4_FILES_AVAIL_MASK |
738 			    FATTR4_FILES_FREE_MASK |
739 			    FATTR4_FILES_TOTAL_MASK |
740 			    FATTR4_FILES_AVAIL_MASK |
741 			    FATTR4_FILES_FREE_MASK |
742 			    FATTR4_FILES_TOTAL_MASK)) {
743 				if (error =
744 				    rfs4_get_sb_encode(dvp->v_vfsp,
745 				    &sbe)) {
746 					/* Remove attrs from encode */
747 					ae &= ~(FATTR4_FILES_AVAIL_MASK |
748 					    FATTR4_FILES_FREE_MASK |
749 					    FATTR4_FILES_TOTAL_MASK |
750 					    FATTR4_FILES_AVAIL_MASK |
751 					    FATTR4_FILES_FREE_MASK |
752 					    FATTR4_FILES_TOTAL_MASK);
753 					rddirattr_error = error;
754 				}
755 			}
756 			if (ar & (FATTR4_MAXFILESIZE_MASK |
757 			    FATTR4_MAXLINK_MASK |
758 			    FATTR4_MAXNAME_MASK)) {
759 				if (error = rfs4_get_pc_encode(cs->vp,
760 				    &pce, ar, cs->cr)) {
761 					ar &= ~(FATTR4_MAXFILESIZE_MASK |
762 					    FATTR4_MAXLINK_MASK |
763 					    FATTR4_MAXNAME_MASK);
764 					rddirattr_error = error;
765 				}
766 			}
767 		}
768 
769 reencode_attrs:
770 		/* encode the BOOLEAN for the existence of the next entry */
771 		IXDR_PUT_U_INT32(ptr, true);
772 		/* encode the COOKIE for the entry */
773 		IXDR_PUT_U_HYPER(ptr, dp->d_off);
774 
775 		name = nfscmd_convname(ca, cs->exi, dp->d_name,
776 		    NFSCMD_CONV_OUTBOUND, MAXPATHLEN + 1);
777 
778 		if (name == NULL) {
779 			rddir_next_offset = dp->d_off;
780 			continue;
781 		}
782 		/* Calculate the dirent name length */
783 		namelen = strlen(name);
784 
785 		rndup = RNDUP(namelen) / BYTES_PER_XDR_UNIT;
786 
787 		/* room for LENGTH + string ? */
788 		if ((ptr + (1 + rndup)) > ptr_redzone) {
789 			no_space = TRUE;
790 			continue;
791 		}
792 
793 		/* encode the LENGTH of the name */
794 		IXDR_PUT_U_INT32(ptr, namelen);
795 		/* encode the RNDUP FILL first */
796 		ptr[rndup - 1] = 0;
797 		/* encode the NAME of the entry */
798 		bcopy(name, (char *)ptr, namelen);
799 		/* now bump the ptr after... */
800 		ptr += rndup;
801 
802 		if (name != dp->d_name)
803 			kmem_free(name, MAXPATHLEN + 1);
804 
805 		/*
806 		 * Keep checking on the dircount to see if we have
807 		 * reached the limit; from the RFC, dircount is to be
808 		 * the XDR encoded limit of the cookie plus name.
809 		 * So the count is the name, XDR_UNIT of length for
810 		 * that name and 2 * XDR_UNIT bytes of cookie;
811 		 * However, use the regular DIRENT64 to match most
812 		 * client's APIs.
813 		 */
814 		dircount -= DIRENT64_RECLEN(namelen);
815 		if (nents != 0 && dircount < 0) {
816 			no_space = TRUE;
817 			continue;
818 		}
819 
820 		/*
821 		 * Attributes requested?
822 		 * Gather up the attribute info and the previous VOP_LOOKUP()
823 		 * succeeded; if an error occurs on the VOP_GETATTR() then
824 		 * return just the error (again if it is requested).
825 		 * Note that the previous VOP_LOOKUP() could have failed
826 		 * itself which leaves this code without anything for
827 		 * a VOP_GETATTR().
828 		 * Also note that the readdir_attr_error is left in the
829 		 * encoding mask if requested and so is the mounted_on_fileid.
830 		 */
831 		if (ae != 0) {
832 			if (!vp) {
833 				ae = ar & (FATTR4_RDATTR_ERROR_MASK |
834 				    FATTR4_MOUNTED_ON_FILEID_MASK);
835 			} else {
836 				va.va_mask = AT_ALL;
837 				rddirattr_error =
838 				    VOP_GETATTR(vp, &va, 0, cs->cr, NULL);
839 				if (rddirattr_error) {
840 					ae = ar & (FATTR4_RDATTR_ERROR_MASK |
841 					    FATTR4_MOUNTED_ON_FILEID_MASK);
842 				} else {
843 					/*
844 					 * We may lie about the object
845 					 * type for a referral
846 					 */
847 					if (vn_is_nfs_reparse(vp, cs->cr) &&
848 					    client_is_downrev(req))
849 						va.va_type = VLNK;
850 				}
851 			}
852 		}
853 
854 		/* START OF ATTRIBUTE ENCODING */
855 
856 		/* encode the LENGTH of the BITMAP4 array */
857 		IXDR_PUT_U_INT32(ptr, 2);
858 		/* encode the BITMAP4 */
859 		attrmask_ptr = ptr;
860 		IXDR_PUT_HYPER(ptr, ae);
861 		attr_offset_ptr = ptr;
862 		/* encode the default LENGTH of the attributes for entry */
863 		IXDR_PUT_U_INT32(ptr, 0);
864 
865 		if (ptr > ptr_redzone) {
866 			no_space = TRUE;
867 			continue;
868 		}
869 
870 		/* Check if any of the first 32 attributes are being encoded */
871 		if (ae & 0xffffffff00000000) {
872 			/*
873 			 * Redzone check is done at the end of this section.
874 			 * This particular section will encode a maximum of
875 			 * 18 * BYTES_PER_XDR_UNIT of data
876 			 */
877 			if (ae &
878 			    (FATTR4_SUPPORTED_ATTRS_MASK |
879 			    FATTR4_TYPE_MASK |
880 			    FATTR4_FH_EXPIRE_TYPE_MASK |
881 			    FATTR4_CHANGE_MASK |
882 			    FATTR4_SIZE_MASK |
883 			    FATTR4_LINK_SUPPORT_MASK |
884 			    FATTR4_SYMLINK_SUPPORT_MASK |
885 			    FATTR4_NAMED_ATTR_MASK |
886 			    FATTR4_FSID_MASK |
887 			    FATTR4_UNIQUE_HANDLES_MASK |
888 			    FATTR4_LEASE_TIME_MASK |
889 			    FATTR4_RDATTR_ERROR_MASK)) {
890 
891 				if (ae & FATTR4_SUPPORTED_ATTRS_MASK) {
892 					IXDR_PUT_INT32(ptr, 2);
893 					IXDR_PUT_HYPER(ptr,
894 					    rfs4_supported_attrs);
895 				}
896 				if (ae & FATTR4_TYPE_MASK) {
897 					uint_t ftype = vt_to_nf4[va.va_type];
898 					if (dvp->v_flag & V_XATTRDIR) {
899 						if (va.va_type == VDIR)
900 							ftype = NF4ATTRDIR;
901 						else
902 							ftype = NF4NAMEDATTR;
903 					}
904 					IXDR_PUT_U_INT32(ptr, ftype);
905 				}
906 				if (ae & FATTR4_FH_EXPIRE_TYPE_MASK) {
907 					uint_t expire_type = FH4_PERSISTENT;
908 					IXDR_PUT_U_INT32(ptr, expire_type);
909 				}
910 				if (ae & FATTR4_CHANGE_MASK) {
911 					u_longlong_t change;
912 					NFS4_SET_FATTR4_CHANGE(change,
913 					    va.va_ctime);
914 					IXDR_PUT_HYPER(ptr, change);
915 				}
916 				if (ae & FATTR4_SIZE_MASK) {
917 					u_longlong_t size = va.va_size;
918 					IXDR_PUT_HYPER(ptr, size);
919 				}
920 				if (ae & FATTR4_LINK_SUPPORT_MASK) {
921 					IXDR_PUT_U_INT32(ptr, true);
922 				}
923 				if (ae & FATTR4_SYMLINK_SUPPORT_MASK) {
924 					IXDR_PUT_U_INT32(ptr, true);
925 				}
926 				if (ae & FATTR4_NAMED_ATTR_MASK) {
927 					uint_t isit;
928 					pc_val = FALSE;
929 					int sattr_error;
930 
931 					if (!(vp->v_vfsp->vfs_flag &
932 					    VFS_XATTR)) {
933 						isit = FALSE;
934 					} else {
935 						sattr_error = VOP_PATHCONF(vp,
936 						    _PC_SATTR_EXISTS,
937 						    &pc_val, cs->cr, NULL);
938 						if (sattr_error || pc_val == 0)
939 							(void) VOP_PATHCONF(vp,
940 							    _PC_XATTR_EXISTS,
941 							    &pc_val,
942 							    cs->cr, NULL);
943 					}
944 					isit = (pc_val ? TRUE : FALSE);
945 					IXDR_PUT_U_INT32(ptr, isit);
946 				}
947 				if (ae & FATTR4_FSID_MASK) {
948 					u_longlong_t major, minor;
949 					struct exportinfo *exi;
950 
951 					exi = newexi ? newexi : cs->exi;
952 					if (exi->exi_volatile_dev) {
953 						int *pmaj = (int *)&major;
954 
955 						pmaj[0] = exi->exi_fsid.val[0];
956 						pmaj[1] = exi->exi_fsid.val[1];
957 						minor = 0;
958 					} else {
959 						major = getmajor(va.va_fsid);
960 						minor = getminor(va.va_fsid);
961 					}
962 					IXDR_PUT_HYPER(ptr, major);
963 					IXDR_PUT_HYPER(ptr, minor);
964 				}
965 				if (ae & FATTR4_UNIQUE_HANDLES_MASK) {
966 					IXDR_PUT_U_INT32(ptr, false);
967 				}
968 				if (ae & FATTR4_LEASE_TIME_MASK) {
969 					uint_t lt = rfs4_lease_time;
970 					IXDR_PUT_U_INT32(ptr, lt);
971 				}
972 				if (ae & FATTR4_RDATTR_ERROR_MASK) {
973 					rddirattr_error =
974 					    (rddirattr_error == 0 ?
975 					    0 : puterrno4(rddirattr_error));
976 					IXDR_PUT_U_INT32(ptr, rddirattr_error);
977 				}
978 
979 				/* Check the redzone boundary */
980 				if (ptr > ptr_redzone) {
981 					if (nents || IS_MIN_ATTR_MASK(ar)) {
982 						no_space = TRUE;
983 						continue;
984 					}
985 					MINIMIZE_ATTR_MASK(ar);
986 					ae = ar;
987 					ptr = lastentry_ptr;
988 					goto reencode_attrs;
989 				}
990 			}
991 			/*
992 			 * Redzone check is done at the end of this section.
993 			 * This particular section will encode a maximum of
994 			 * 4 * BYTES_PER_XDR_UNIT of data.
995 			 * NOTE: that if ACLs are supported that the
996 			 * redzone calculations will need to change.
997 			 */
998 			if (ae &
999 			    (FATTR4_ACL_MASK |
1000 			    FATTR4_ACLSUPPORT_MASK |
1001 			    FATTR4_ARCHIVE_MASK |
1002 			    FATTR4_CANSETTIME_MASK |
1003 			    FATTR4_CASE_INSENSITIVE_MASK |
1004 			    FATTR4_CASE_PRESERVING_MASK |
1005 			    FATTR4_CHOWN_RESTRICTED_MASK)) {
1006 
1007 				if (ae & FATTR4_ACL_MASK) {
1008 					ASSERT(0);
1009 				}
1010 				if (ae & FATTR4_ACLSUPPORT_MASK) {
1011 					ASSERT(0);
1012 				}
1013 				if (ae & FATTR4_ARCHIVE_MASK) {
1014 					ASSERT(0);
1015 				}
1016 				if (ae & FATTR4_CANSETTIME_MASK) {
1017 					IXDR_PUT_U_INT32(ptr, true);
1018 				}
1019 				if (ae & FATTR4_CASE_INSENSITIVE_MASK) {
1020 					IXDR_PUT_U_INT32(ptr, false);
1021 				}
1022 				if (ae & FATTR4_CASE_PRESERVING_MASK) {
1023 					IXDR_PUT_U_INT32(ptr, true);
1024 				}
1025 				if (ae & FATTR4_CHOWN_RESTRICTED_MASK) {
1026 					uint_t isit;
1027 					pc_val = FALSE;
1028 					(void) VOP_PATHCONF(vp,
1029 					    _PC_CHOWN_RESTRICTED,
1030 					    &pc_val, cs->cr, NULL);
1031 					isit = (pc_val ? TRUE : FALSE);
1032 					IXDR_PUT_U_INT32(ptr, isit);
1033 				}
1034 				/* Check the redzone boundary */
1035 				if (ptr > ptr_redzone) {
1036 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1037 						no_space = TRUE;
1038 						continue;
1039 					}
1040 					MINIMIZE_ATTR_MASK(ar);
1041 					ae = ar;
1042 					ptr = lastentry_ptr;
1043 					goto reencode_attrs;
1044 				}
1045 			}
1046 			/*
1047 			 * Redzone check is done before the filehandle
1048 			 * is encoded.
1049 			 */
1050 			if (ae &
1051 			    (FATTR4_FILEHANDLE_MASK |
1052 			    FATTR4_FILEID_MASK)) {
1053 
1054 				if (ae & FATTR4_FILEHANDLE_MASK) {
1055 					struct {
1056 						uint_t len;
1057 						char *val;
1058 						char fh[NFS_FH4_LEN];
1059 					} fh;
1060 					fh.len = 0;
1061 					fh.val = fh.fh;
1062 					(void) makefh4((nfs_fh4 *)&fh, vp,
1063 					    (newexi ? newexi : cs->exi));
1064 
1065 					if (dvp->v_flag & V_XATTRDIR)
1066 						set_fh4_flag((nfs_fh4 *)&fh,
1067 						    FH4_NAMEDATTR);
1068 
1069 					if (!xdr_inline_encode_nfs_fh4(
1070 					    &ptr, ptr_redzone,
1071 					    (nfs_fh4_fmt_t *)fh.val)) {
1072 						if (nents ||
1073 						    IS_MIN_ATTR_MASK(ar)) {
1074 							no_space = TRUE;
1075 							continue;
1076 						}
1077 						MINIMIZE_ATTR_MASK(ar);
1078 						ae = ar;
1079 						ptr = lastentry_ptr;
1080 						goto reencode_attrs;
1081 					}
1082 				}
1083 				if (ae & FATTR4_FILEID_MASK) {
1084 					IXDR_PUT_HYPER(ptr, va.va_nodeid);
1085 				}
1086 				/* Check the redzone boundary */
1087 				if (ptr > ptr_redzone) {
1088 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1089 						no_space = TRUE;
1090 						continue;
1091 					}
1092 					MINIMIZE_ATTR_MASK(ar);
1093 					ae = ar;
1094 					ptr = lastentry_ptr;
1095 					goto reencode_attrs;
1096 				}
1097 			}
1098 			/*
1099 			 * Redzone check is done at the end of this section.
1100 			 * This particular section will encode a maximum of
1101 			 * 15 * BYTES_PER_XDR_UNIT of data.
1102 			 */
1103 			if (ae &
1104 			    (FATTR4_FILES_AVAIL_MASK |
1105 			    FATTR4_FILES_FREE_MASK |
1106 			    FATTR4_FILES_TOTAL_MASK |
1107 			    FATTR4_FS_LOCATIONS_MASK |
1108 			    FATTR4_HIDDEN_MASK |
1109 			    FATTR4_HOMOGENEOUS_MASK |
1110 			    FATTR4_MAXFILESIZE_MASK |
1111 			    FATTR4_MAXLINK_MASK |
1112 			    FATTR4_MAXNAME_MASK |
1113 			    FATTR4_MAXREAD_MASK |
1114 			    FATTR4_MAXWRITE_MASK)) {
1115 
1116 				if (ae & FATTR4_FILES_AVAIL_MASK) {
1117 					IXDR_PUT_HYPER(ptr, sbe.fa);
1118 				}
1119 				if (ae & FATTR4_FILES_FREE_MASK) {
1120 					IXDR_PUT_HYPER(ptr, sbe.ff);
1121 				}
1122 				if (ae & FATTR4_FILES_TOTAL_MASK) {
1123 					IXDR_PUT_HYPER(ptr, sbe.ft);
1124 				}
1125 				if (ae & FATTR4_FS_LOCATIONS_MASK) {
1126 					ASSERT(0);
1127 				}
1128 				if (ae & FATTR4_HIDDEN_MASK) {
1129 					ASSERT(0);
1130 				}
1131 				if (ae & FATTR4_HOMOGENEOUS_MASK) {
1132 					IXDR_PUT_U_INT32(ptr, true);
1133 				}
1134 				if (ae & FATTR4_MAXFILESIZE_MASK) {
1135 					IXDR_PUT_HYPER(ptr, pce.maxfilesize);
1136 				}
1137 				if (ae & FATTR4_MAXLINK_MASK) {
1138 					IXDR_PUT_U_INT32(ptr, pce.maxlink);
1139 				}
1140 				if (ae & FATTR4_MAXNAME_MASK) {
1141 					IXDR_PUT_U_INT32(ptr, pce.maxname);
1142 				}
1143 				if (ae & FATTR4_MAXREAD_MASK) {
1144 					IXDR_PUT_HYPER(ptr, maxread);
1145 				}
1146 				if (ae & FATTR4_MAXWRITE_MASK) {
1147 					IXDR_PUT_HYPER(ptr, maxwrite);
1148 				}
1149 				/* Check the redzone boundary */
1150 				if (ptr > ptr_redzone) {
1151 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1152 						no_space = TRUE;
1153 						continue;
1154 					}
1155 					MINIMIZE_ATTR_MASK(ar);
1156 					ae = ar;
1157 					ptr = lastentry_ptr;
1158 					goto reencode_attrs;
1159 				}
1160 			}
1161 		}
1162 		if (ae & 0x00000000ffffffff) {
1163 			/*
1164 			 * Redzone check is done at the end of this section.
1165 			 * This particular section will encode a maximum of
1166 			 * 3 * BYTES_PER_XDR_UNIT of data.
1167 			 */
1168 			if (ae &
1169 			    (FATTR4_MIMETYPE_MASK |
1170 			    FATTR4_MODE_MASK |
1171 			    FATTR4_NO_TRUNC_MASK |
1172 			    FATTR4_NUMLINKS_MASK)) {
1173 
1174 				if (ae & FATTR4_MIMETYPE_MASK) {
1175 					ASSERT(0);
1176 				}
1177 				if (ae & FATTR4_MODE_MASK) {
1178 					uint_t m = va.va_mode;
1179 					IXDR_PUT_U_INT32(ptr, m);
1180 				}
1181 				if (ae & FATTR4_NO_TRUNC_MASK) {
1182 					IXDR_PUT_U_INT32(ptr, true);
1183 				}
1184 				if (ae & FATTR4_NUMLINKS_MASK) {
1185 					IXDR_PUT_U_INT32(ptr, va.va_nlink);
1186 				}
1187 				/* Check the redzone boundary */
1188 				if (ptr > ptr_redzone) {
1189 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1190 						no_space = TRUE;
1191 						continue;
1192 					}
1193 					MINIMIZE_ATTR_MASK(ar);
1194 					ae = ar;
1195 					ptr = lastentry_ptr;
1196 					goto reencode_attrs;
1197 				}
1198 			}
1199 			/*
1200 			 * Redzone check is done before the encoding of the
1201 			 * owner string since the length is indeterminate.
1202 			 */
1203 			if (ae & FATTR4_OWNER_MASK) {
1204 				if (!lu_set) {
1205 					owner_error = nfs_idmap_uid_str(
1206 					    va.va_uid, &owner, TRUE);
1207 					if (!owner_error) {
1208 						lu_set = TRUE;
1209 						lastuid = va.va_uid;
1210 					}
1211 				} else 	if (va.va_uid != lastuid) {
1212 					if (owner.utf8string_len != 0) {
1213 						kmem_free(owner.utf8string_val,
1214 						    owner.utf8string_len);
1215 						owner.utf8string_len = 0;
1216 						owner.utf8string_val = NULL;
1217 					}
1218 					owner_error = nfs_idmap_uid_str(
1219 					    va.va_uid, &owner, TRUE);
1220 					if (!owner_error) {
1221 						lastuid = va.va_uid;
1222 					} else {
1223 						lu_set = FALSE;
1224 					}
1225 				}
1226 				if (!owner_error) {
1227 					if ((ptr +
1228 					    (owner.utf8string_len /
1229 					    BYTES_PER_XDR_UNIT)
1230 					    + 2) > ptr_redzone) {
1231 						if (nents ||
1232 						    IS_MIN_ATTR_MASK(ar)) {
1233 							no_space = TRUE;
1234 							continue;
1235 						}
1236 						MINIMIZE_ATTR_MASK(ar);
1237 						ae = ar;
1238 						ptr = lastentry_ptr;
1239 						goto reencode_attrs;
1240 					}
1241 					/* encode the LENGTH of owner string */
1242 					IXDR_PUT_U_INT32(ptr,
1243 					    owner.utf8string_len);
1244 					/* encode the RNDUP FILL first */
1245 					rndup = RNDUP(owner.utf8string_len) /
1246 					    BYTES_PER_XDR_UNIT;
1247 					ptr[rndup - 1] = 0;
1248 					/* encode the OWNER */
1249 					bcopy(owner.utf8string_val, ptr,
1250 					    owner.utf8string_len);
1251 					ptr += rndup;
1252 				}
1253 			}
1254 			/*
1255 			 * Redzone check is done before the encoding of the
1256 			 * group string since the length is indeterminate.
1257 			 */
1258 			if (ae & FATTR4_OWNER_GROUP_MASK) {
1259 				if (!lg_set) {
1260 					group_error =
1261 					    nfs_idmap_gid_str(va.va_gid,
1262 					    &group, TRUE);
1263 					if (!group_error) {
1264 						lg_set = TRUE;
1265 						lastgid = va.va_gid;
1266 					}
1267 				} else if (va.va_gid != lastgid) {
1268 					if (group.utf8string_len != 0) {
1269 						kmem_free(
1270 						    group.utf8string_val,
1271 						    group.utf8string_len);
1272 						group.utf8string_len = 0;
1273 						group.utf8string_val = NULL;
1274 					}
1275 					group_error =
1276 					    nfs_idmap_gid_str(va.va_gid,
1277 					    &group, TRUE);
1278 					if (!group_error)
1279 						lastgid = va.va_gid;
1280 					else
1281 						lg_set = FALSE;
1282 				}
1283 				if (!group_error) {
1284 					if ((ptr +
1285 					    (group.utf8string_len /
1286 					    BYTES_PER_XDR_UNIT)
1287 					    + 2) > ptr_redzone) {
1288 						if (nents ||
1289 						    IS_MIN_ATTR_MASK(ar)) {
1290 							no_space = TRUE;
1291 							continue;
1292 						}
1293 						MINIMIZE_ATTR_MASK(ar);
1294 						ae = ar;
1295 						ptr = lastentry_ptr;
1296 						goto reencode_attrs;
1297 					}
1298 					/* encode the LENGTH of owner string */
1299 					IXDR_PUT_U_INT32(ptr,
1300 					    group.utf8string_len);
1301 					/* encode the RNDUP FILL first */
1302 					rndup = RNDUP(group.utf8string_len) /
1303 					    BYTES_PER_XDR_UNIT;
1304 					ptr[rndup - 1] = 0;
1305 					/* encode the OWNER */
1306 					bcopy(group.utf8string_val, ptr,
1307 					    group.utf8string_len);
1308 					ptr += rndup;
1309 				}
1310 			}
1311 			if (ae &
1312 			    (FATTR4_QUOTA_AVAIL_HARD_MASK |
1313 			    FATTR4_QUOTA_AVAIL_SOFT_MASK |
1314 			    FATTR4_QUOTA_USED_MASK)) {
1315 				if (ae & FATTR4_QUOTA_AVAIL_HARD_MASK) {
1316 					ASSERT(0);
1317 				}
1318 				if (ae & FATTR4_QUOTA_AVAIL_SOFT_MASK) {
1319 					ASSERT(0);
1320 				}
1321 				if (ae & FATTR4_QUOTA_USED_MASK) {
1322 					ASSERT(0);
1323 				}
1324 			}
1325 			/*
1326 			 * Redzone check is done at the end of this section.
1327 			 * This particular section will encode a maximum of
1328 			 * 10 * BYTES_PER_XDR_UNIT of data.
1329 			 */
1330 			if (ae &
1331 			    (FATTR4_RAWDEV_MASK |
1332 			    FATTR4_SPACE_AVAIL_MASK |
1333 			    FATTR4_SPACE_FREE_MASK |
1334 			    FATTR4_SPACE_TOTAL_MASK |
1335 			    FATTR4_SPACE_USED_MASK |
1336 			    FATTR4_SYSTEM_MASK)) {
1337 
1338 				if (ae & FATTR4_RAWDEV_MASK) {
1339 					fattr4_rawdev rd;
1340 					rd.specdata1 =
1341 					    (uint32)getmajor(va.va_rdev);
1342 					rd.specdata2 =
1343 					    (uint32)getminor(va.va_rdev);
1344 					IXDR_PUT_U_INT32(ptr, rd.specdata1);
1345 					IXDR_PUT_U_INT32(ptr, rd.specdata2);
1346 				}
1347 				if (ae & FATTR4_SPACE_AVAIL_MASK) {
1348 					IXDR_PUT_HYPER(ptr, sbe.space_avail);
1349 				}
1350 				if (ae & FATTR4_SPACE_FREE_MASK) {
1351 					IXDR_PUT_HYPER(ptr, sbe.space_free);
1352 				}
1353 				if (ae & FATTR4_SPACE_TOTAL_MASK) {
1354 					IXDR_PUT_HYPER(ptr, sbe.space_total);
1355 				}
1356 				if (ae & FATTR4_SPACE_USED_MASK) {
1357 					u_longlong_t su;
1358 					su = (fattr4_space_used) DEV_BSIZE *
1359 					    (fattr4_space_used) va.va_nblocks;
1360 					IXDR_PUT_HYPER(ptr, su);
1361 				}
1362 				if (ae & FATTR4_SYSTEM_MASK) {
1363 					ASSERT(0);
1364 				}
1365 				/* Check the redzone boundary */
1366 				if (ptr > ptr_redzone) {
1367 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1368 						no_space = TRUE;
1369 						continue;
1370 					}
1371 					MINIMIZE_ATTR_MASK(ar);
1372 					ae = ar;
1373 					ptr = lastentry_ptr;
1374 					goto reencode_attrs;
1375 				}
1376 			}
1377 			/*
1378 			 * Redzone check is done at the end of this section.
1379 			 * This particular section will encode a maximum of
1380 			 * 14 * BYTES_PER_XDR_UNIT of data.
1381 			 */
1382 			if (ae &
1383 			    (FATTR4_TIME_ACCESS_MASK |
1384 			    FATTR4_TIME_ACCESS_SET_MASK |
1385 			    FATTR4_TIME_BACKUP_MASK |
1386 			    FATTR4_TIME_CREATE_MASK |
1387 			    FATTR4_TIME_DELTA_MASK |
1388 			    FATTR4_TIME_METADATA_MASK |
1389 			    FATTR4_TIME_MODIFY_MASK |
1390 			    FATTR4_TIME_MODIFY_SET_MASK |
1391 			    FATTR4_MOUNTED_ON_FILEID_MASK)) {
1392 
1393 				if (ae & FATTR4_TIME_ACCESS_MASK) {
1394 					u_longlong_t sec =
1395 					    (u_longlong_t)va.va_atime.tv_sec;
1396 					uint_t nsec =
1397 					    (uint_t)va.va_atime.tv_nsec;
1398 					IXDR_PUT_HYPER(ptr, sec);
1399 					IXDR_PUT_INT32(ptr, nsec);
1400 				}
1401 				if (ae & FATTR4_TIME_ACCESS_SET_MASK) {
1402 					ASSERT(0);
1403 				}
1404 				if (ae & FATTR4_TIME_BACKUP_MASK) {
1405 					ASSERT(0);
1406 				}
1407 				if (ae & FATTR4_TIME_CREATE_MASK) {
1408 					ASSERT(0);
1409 				}
1410 				if (ae & FATTR4_TIME_DELTA_MASK) {
1411 					u_longlong_t sec = 0;
1412 					uint_t nsec = 1000;
1413 					IXDR_PUT_HYPER(ptr, sec);
1414 					IXDR_PUT_INT32(ptr, nsec);
1415 				}
1416 				if (ae & FATTR4_TIME_METADATA_MASK) {
1417 					u_longlong_t sec =
1418 					    (u_longlong_t)va.va_ctime.tv_sec;
1419 					uint_t nsec =
1420 					    (uint_t)va.va_ctime.tv_nsec;
1421 					IXDR_PUT_HYPER(ptr, sec);
1422 					IXDR_PUT_INT32(ptr, nsec);
1423 				}
1424 				if (ae & FATTR4_TIME_MODIFY_MASK) {
1425 					u_longlong_t sec =
1426 					    (u_longlong_t)va.va_mtime.tv_sec;
1427 					uint_t nsec =
1428 					    (uint_t)va.va_mtime.tv_nsec;
1429 					IXDR_PUT_HYPER(ptr, sec);
1430 					IXDR_PUT_INT32(ptr, nsec);
1431 				}
1432 				if (ae & FATTR4_TIME_MODIFY_SET_MASK) {
1433 					ASSERT(0);
1434 				}
1435 				if (ae & FATTR4_MOUNTED_ON_FILEID_MASK) {
1436 					IXDR_PUT_HYPER(ptr, dp->d_ino);
1437 				}
1438 				/* Check the redzone boundary */
1439 				if (ptr > ptr_redzone) {
1440 					if (nents || IS_MIN_ATTR_MASK(ar)) {
1441 						no_space = TRUE;
1442 						continue;
1443 					}
1444 					MINIMIZE_ATTR_MASK(ar);
1445 					ae = ar;
1446 					ptr = lastentry_ptr;
1447 					goto reencode_attrs;
1448 				}
1449 			}
1450 		}
1451 
1452 		/* Reset to directory's vfs info when encoding complete */
1453 		if (vfs_different) {
1454 			dsbe = sbe;
1455 			dpce = pce;
1456 			vfs_different = 0;
1457 		}
1458 
1459 		/* "go back" and encode the attributes' length */
1460 		attr_length =
1461 		    (char *)ptr -
1462 		    (char *)attr_offset_ptr -
1463 		    BYTES_PER_XDR_UNIT;
1464 		IXDR_PUT_U_INT32(attr_offset_ptr, attr_length);
1465 
1466 		/*
1467 		 * If there was trouble obtaining a mapping for either
1468 		 * the owner or group attributes, then remove them from
1469 		 * bitmap4 for this entry and reset the bitmap value
1470 		 * in the data stream.
1471 		 */
1472 		if (owner_error || group_error) {
1473 			if (owner_error)
1474 				ae &= ~FATTR4_OWNER_MASK;
1475 			if (group_error)
1476 				ae &= ~FATTR4_OWNER_GROUP_MASK;
1477 			IXDR_PUT_HYPER(attrmask_ptr, ae);
1478 		}
1479 
1480 		/* END OF ATTRIBUTE ENCODING */
1481 
1482 		lastentry_ptr = ptr;
1483 		nents++;
1484 		rddir_next_offset = dp->d_off;
1485 	}
1486 
1487 	/*
1488 	 * Check for the case that another VOP_READDIR() has to be done.
1489 	 * - no space encoding error
1490 	 * - no entry successfully encoded
1491 	 * - still more directory to read
1492 	 */
1493 	if (!no_space && nents == 0 && !iseofdir)
1494 		goto readagain;
1495 
1496 	*cs->statusp = resp->status = NFS4_OK;
1497 
1498 	/*
1499 	 * If no_space is set then we terminated prematurely,
1500 	 * rewind to the last entry and this can never be EOF.
1501 	 */
1502 	if (no_space) {
1503 		ptr = lastentry_ptr;
1504 		eof = FALSE; /* ended encoded prematurely */
1505 	} else {
1506 		eof = (iseofdir ? TRUE : FALSE);
1507 	}
1508 
1509 	/*
1510 	 * If we have entries, always return them, otherwise only error
1511 	 * if we ran out of space.
1512 	 */
1513 	if (nents || !no_space) {
1514 		ASSERT(ptr != NULL);
1515 		/* encode the BOOLEAN marking no further entries */
1516 		IXDR_PUT_U_INT32(ptr, false);
1517 		/* encode the BOOLEAN signifying end of directory */
1518 		IXDR_PUT_U_INT32(ptr, eof);
1519 
1520 		resp->data_len = (char *)ptr - (char *)beginning_ptr;
1521 		resp->mblk->b_wptr += resp->data_len;
1522 	} else {
1523 		freeb(mp);
1524 		resp->mblk = NULL;
1525 		resp->data_len = 0;
1526 		*cs->statusp = resp->status = NFS4ERR_TOOSMALL;
1527 	}
1528 
1529 	kmem_free((caddr_t)rddir_data, rddir_data_len);
1530 	if (vp)
1531 		VN_RELE(vp);
1532 	if (owner.utf8string_len != 0)
1533 		kmem_free(owner.utf8string_val,	owner.utf8string_len);
1534 	if (group.utf8string_len != 0)
1535 		kmem_free(group.utf8string_val, group.utf8string_len);
1536 
1537 out:
1538 	DTRACE_NFSV4_2(op__readdir__done, struct compound_state *, cs,
1539 	    READDIR4res *, resp);
1540 }
1541