1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2018 Nexenta Systems, Inc.  All rights reserved.
14  */
15 
16 /*
17  * Support functions for smb2_ioctl/fsctl codes:
18  * FSCTL_SET_SPARSE
19  * FSCTL_SET_ZERO_DATA
20  * FSCTL_QUERY_ALLOCATED_RANGES
21  */
22 
23 #include <smbsrv/smb2_kproto.h>
24 #include <smbsrv/smb_fsops.h>
25 #include <smb/winioctl.h>
26 
27 /*
28  * FSCTL_SET_SPARSE
29  *
30  * In args: one byte flag (optional: default TRUE)
31  */
32 uint32_t
smb2_fsctl_set_sparse(smb_request_t * sr,smb_fsctl_t * fsctl)33 smb2_fsctl_set_sparse(smb_request_t *sr, smb_fsctl_t *fsctl)
34 {
35 	smb_attr_t attr;
36 	smb_ofile_t *ofile = sr->fid_ofile;
37 	cred_t *kcr;
38 	uint32_t amask;
39 	uint32_t status;
40 	uint8_t flag;
41 	int rc;
42 
43 	rc = smb_mbc_decodef(fsctl->in_mbc, "b", &flag);
44 	if (rc != 0)
45 		flag = 0xff;
46 
47 	if (!smb_node_is_file(ofile->f_node))
48 		return (NT_STATUS_INVALID_PARAMETER);
49 
50 	/*
51 	 * Allow if we have any of FILE_WRITE_ATTRIBUTES,
52 	 * FILE_WRITE_DATA, FILE_APPEND_DATA
53 	 */
54 	amask = FILE_WRITE_ATTRIBUTES | FILE_WRITE_DATA | FILE_APPEND_DATA;
55 	if ((ofile->f_granted_access & amask) == 0)
56 		return (NT_STATUS_ACCESS_DENIED);
57 
58 	/*
59 	 * Need the current DOS attributes
60 	 */
61 	bzero(&attr, sizeof (attr));
62 	attr.sa_mask = SMB_AT_DOSATTR;
63 	kcr = zone_kcred();
64 	status = smb_node_getattr(sr, ofile->f_node, kcr, ofile, &attr);
65 	if (status != NT_STATUS_SUCCESS)
66 		return (status);
67 
68 	if (flag != 0) {
69 		/* Set "sparse" */
70 		if (attr.sa_dosattr & FILE_ATTRIBUTE_SPARSE_FILE)
71 			return (0);
72 		attr.sa_dosattr |= FILE_ATTRIBUTE_SPARSE_FILE;
73 	} else {
74 		/* Clear "sparse" */
75 		if ((attr.sa_dosattr & FILE_ATTRIBUTE_SPARSE_FILE) == 0)
76 			return (0);
77 		attr.sa_dosattr &= ~FILE_ATTRIBUTE_SPARSE_FILE;
78 	}
79 
80 	attr.sa_mask = SMB_AT_DOSATTR;
81 	status = smb_node_setattr(sr, ofile->f_node, kcr, ofile, &attr);
82 	return (status);
83 }
84 
85 /*
86  * FSCTL_SET_ZERO_DATA
87  *
88  * In args: uint64_t start_off, end_off
89  */
90 uint32_t
smb2_fsctl_set_zero_data(smb_request_t * sr,smb_fsctl_t * fsctl)91 smb2_fsctl_set_zero_data(smb_request_t *sr, smb_fsctl_t *fsctl)
92 {
93 	smb_attr_t attr;
94 	smb_ofile_t *ofile = sr->fid_ofile;
95 	uint64_t start_off, end_off, zero_len;
96 	uint32_t status;
97 	int rc;
98 
99 	rc = smb_mbc_decodef(fsctl->in_mbc, "qq",
100 	    &start_off, &end_off);
101 	if (rc != 0)
102 		return (NT_STATUS_BUFFER_TOO_SMALL);
103 
104 	/*
105 	 * The given offsets are actually int64_t (signed).
106 	 */
107 	if (start_off > INT64_MAX ||
108 	    end_off > INT64_MAX ||
109 	    start_off > end_off)
110 		return (NT_STATUS_INVALID_PARAMETER);
111 
112 	if (!smb_node_is_file(ofile->f_node))
113 		return (NT_STATUS_INVALID_PARAMETER);
114 
115 	/*
116 	 * This operation is effectively a write (of zeros)
117 	 */
118 	status = smb_ofile_access(ofile, ofile->f_cr, FILE_WRITE_DATA);
119 	if (status != NT_STATUS_SUCCESS)
120 		return (status);
121 
122 	/*
123 	 * Need the file size
124 	 */
125 	bzero(&attr, sizeof (attr));
126 	attr.sa_mask = SMB_AT_SIZE;
127 	status = smb_node_getattr(sr, ofile->f_node, ofile->f_cr,
128 	    ofile, &attr);
129 	if (status != NT_STATUS_SUCCESS)
130 		return (status);
131 
132 	/*
133 	 * Ignore any zero-ing beyond EOF
134 	 */
135 	if (end_off > attr.sa_vattr.va_size)
136 		end_off = attr.sa_vattr.va_size;
137 	if (start_off >= end_off)
138 		return (0);
139 	zero_len = end_off - start_off;
140 
141 	/*
142 	 * Check for lock conflicting with the write.
143 	 */
144 	status = smb_lock_range_access(sr, ofile->f_node,
145 	    start_off, zero_len, B_TRUE);
146 	if (status != 0)
147 		return (status); /* == FILE_LOCK_CONFLICT */
148 
149 	rc = smb_fsop_freesp(sr, ofile->f_cr, ofile,
150 	    start_off, zero_len);
151 	if (rc != 0)
152 		status = smb_errno2status(rc);
153 
154 	return (status);
155 }
156 
157 /*
158  * FSCTL_QUERY_ALLOCATED_RANGES
159  *
160  * Incoming args: uint64_t start_off, end_off
161  */
162 struct alloc_range {
163 	off64_t off;
164 	off64_t len;
165 };
166 uint32_t
smb2_fsctl_query_alloc_ranges(smb_request_t * sr,smb_fsctl_t * fsctl)167 smb2_fsctl_query_alloc_ranges(smb_request_t *sr, smb_fsctl_t *fsctl)
168 {
169 	smb_attr_t attr;
170 	cred_t *kcr;
171 	smb_ofile_t *ofile = sr->fid_ofile;
172 	struct alloc_range arg, res;
173 	off64_t cur_off, end_off;
174 	uint32_t status;
175 	int err, rc;
176 
177 	/*
178 	 * Most ioctls return NT_STATUS_BUFFER_TOO_SMALL for
179 	 * short in/out buffers, but for this one, MS-FSA
180 	 * says short input returns invalid parameter.
181 	 */
182 	rc = smb_mbc_decodef(fsctl->in_mbc, "qq", &arg.off, &arg.len);
183 	if (rc != 0)
184 		return (NT_STATUS_INVALID_PARAMETER);
185 
186 	/*
187 	 * The given offsets are actually int64_t (signed).
188 	 */
189 	end_off = arg.off + arg.len;
190 	if (arg.off > INT64_MAX || arg.len < 0 ||
191 	    end_off > INT64_MAX || end_off < arg.off)
192 		return (NT_STATUS_INVALID_PARAMETER);
193 
194 	if (!smb_node_is_file(ofile->f_node))
195 		return (NT_STATUS_INVALID_PARAMETER);
196 
197 	/*
198 	 * This operation is effectively a read
199 	 */
200 	status = smb_ofile_access(ofile, ofile->f_cr, FILE_READ_DATA);
201 	if (status != NT_STATUS_SUCCESS)
202 		return (status);
203 
204 	if (arg.len == 0) {
205 		/* MS-FSA says empty result for this. */
206 		return (0);
207 	}
208 
209 	/*
210 	 * Need the file size and dosattr
211 	 */
212 	bzero(&attr, sizeof (attr));
213 	attr.sa_mask = SMB_AT_SIZE | SMB_AT_DOSATTR;
214 	kcr = zone_kcred();
215 	status = smb_node_getattr(sr, ofile->f_node, kcr, ofile, &attr);
216 	if (status != NT_STATUS_SUCCESS)
217 		return (status);
218 	if (end_off > attr.sa_vattr.va_size)
219 		end_off = attr.sa_vattr.va_size;
220 
221 	/*
222 	 * Only sparse files should present un-allocated ranges.
223 	 * If non-sparse, MS-FSA says (just return one range).
224 	 */
225 	if ((attr.sa_dosattr & FILE_ATTRIBUTE_SPARSE_FILE) == 0) {
226 		if (arg.off < end_off) {
227 			res.off = arg.off;
228 			res.len = end_off - arg.off;
229 			rc = smb_mbc_encodef(fsctl->out_mbc, "qq",
230 			    res.off, res.len);
231 			if (rc != 0)
232 				return (NT_STATUS_BUFFER_TOO_SMALL);
233 		}
234 		return (0);
235 	}
236 
237 	cur_off = arg.off;
238 	while (cur_off < end_off) {
239 		off64_t data, hole;
240 
241 		data = cur_off;
242 		err = smb_fsop_next_alloc_range(kcr, ofile->f_node,
243 		    &data, &hole);
244 		if (err != 0)
245 			break;
246 
247 		/* sanity check data (ensure progress) */
248 		if (data < cur_off) {
249 			ASSERT(0);
250 			data = cur_off;
251 		}
252 
253 		/* Normal termination */
254 		if (data >= end_off)
255 			break;
256 
257 		/* sanity check hole (ensure progress) */
258 		if (hole <= data)
259 			hole = end_off;
260 
261 		/* Trim this range as needed. */
262 		if (hole > end_off)
263 			hole = end_off;
264 
265 		res.off = data;
266 		res.len = hole - data;
267 
268 		if (res.len > 0) {
269 			rc = smb_mbc_encodef(fsctl->out_mbc, "qq",
270 			    res.off, res.len);
271 			if (rc != 0)
272 				return (NT_STATUS_BUFFER_TOO_SMALL);
273 		}
274 
275 		cur_off = hole;
276 	}
277 
278 	return (0);
279 }
280 
281 /*
282  * Copy a segment of a file, preserving sparseness.
283  * Uses a caller-provided buffer for read/write.
284  * Caller should already have checked for locks.
285  *
286  * On entry, *residp is the length to copy.
287  * On return, it's the "resid" (amount not copied)
288  *
289  * If this gets an error from any I/O, return it, even if some data
290  * have already been copied.  The caller should normally ignore an
291  * error when some data have been copied.
292  */
293 uint32_t
smb2_sparse_copy(smb_request_t * sr,smb_ofile_t * src_ofile,smb_ofile_t * dst_ofile,off64_t src_off,off64_t dst_off,uint32_t * residp,void * buffer,size_t bufsize)294 smb2_sparse_copy(
295 	smb_request_t *sr,
296 	smb_ofile_t *src_ofile, smb_ofile_t *dst_ofile,
297 	off64_t src_off, off64_t dst_off, uint32_t *residp,
298 	void *buffer, size_t bufsize)
299 {
300 	iovec_t iov;
301 	uio_t uio;
302 	off64_t data, hole;
303 	uint32_t xfer;
304 	uint32_t status = 0;
305 	int rc;
306 
307 	while (*residp > 0) {
308 
309 		data = src_off;
310 		rc = smb_fsop_next_alloc_range(src_ofile->f_cr,
311 		    src_ofile->f_node, &data, &hole);
312 		switch (rc) {
313 		case 0:
314 			/* Found data, hole */
315 			break;
316 		case ENXIO:
317 			/* No data after here (will skip below). */
318 			data = hole = (src_off + *residp);
319 			break;
320 		default:
321 			cmn_err(CE_NOTE,
322 			    "smb_fsop_next_alloc_range: rc=%d", rc);
323 			/* FALLTHROUGH */
324 		case ENOSYS:	/* FS does not support VOP_IOCTL... */
325 		case ENOTTY:	/* ... or _FIO_SEEK_DATA, _HOLE */
326 			data = src_off;
327 			hole = src_off + *residp;
328 			break;
329 		}
330 
331 		/*
332 		 * Don't try to go past (src_off + *residp)
333 		 */
334 		if (hole > (src_off + *residp))
335 			hole = src_off + *residp;
336 		if (data > hole)
337 			data = hole;
338 
339 		/*
340 		 * If there's a gap (src_off .. data)
341 		 * skip in src_ofile, zero in dst_ofile
342 		 */
343 		if (src_off < data) {
344 			off64_t skip = data - src_off;
345 			rc = smb_fsop_freesp(sr, dst_ofile->f_cr,
346 			    dst_ofile, dst_off, skip);
347 			if (rc == 0) {
348 				src_off += skip;
349 				dst_off += skip;
350 				*residp -= (uint32_t)skip;
351 			} else {
352 				/* Fall back to regular copy */
353 				data = src_off;
354 			}
355 		}
356 		ASSERT(src_off == data);
357 
358 		/*
359 		 * Copy this segment: src_off .. hole
360 		 */
361 		while (src_off < hole) {
362 			ssize_t tsize = hole - src_off;
363 			if (tsize > bufsize)
364 				tsize = bufsize;
365 
366 			/*
367 			 * Read src_ofile into buffer
368 			 */
369 			iov.iov_base = buffer;
370 			iov.iov_len  = tsize;
371 			bzero(&uio, sizeof (uio));
372 			uio.uio_iov = &iov;
373 			uio.uio_iovcnt = 1;
374 			uio.uio_resid = tsize;
375 			uio.uio_loffset = src_off;
376 			uio.uio_segflg = UIO_SYSSPACE;
377 			uio.uio_extflg = UIO_COPY_DEFAULT;
378 
379 			rc = smb_fsop_read(sr, src_ofile->f_cr,
380 			    src_ofile->f_node, src_ofile, &uio, 0);
381 			if (rc != 0) {
382 				status = smb_errno2status(rc);
383 				return (status);
384 			}
385 			/* Note: Could be partial read. */
386 			tsize -= uio.uio_resid;
387 			ASSERT(tsize > 0);
388 
389 			/*
390 			 * Write buffer to dst_ofile
391 			 */
392 			iov.iov_base = buffer;
393 			iov.iov_len  = tsize;
394 			bzero(&uio, sizeof (uio));
395 			uio.uio_iov = &iov;
396 			uio.uio_iovcnt = 1;
397 			uio.uio_resid = tsize;
398 			uio.uio_loffset = dst_off;
399 			uio.uio_segflg = UIO_SYSSPACE;
400 			uio.uio_extflg = UIO_COPY_DEFAULT;
401 
402 			rc = smb_fsop_write(sr, dst_ofile->f_cr,
403 			    dst_ofile->f_node, dst_ofile, &uio, &xfer, 0);
404 			if (rc != 0) {
405 				status = smb_errno2status(rc);
406 				return (status);
407 			}
408 			ASSERT(xfer <= tsize);
409 
410 			src_off += xfer;
411 			dst_off += xfer;
412 			*residp -= xfer;
413 		}
414 		ASSERT(src_off == hole);
415 	}
416 
417 	return (status);
418 }
419 
420 /*
421  * Not sure what header this might go in.
422  */
423 #define	FILE_REGION_USAGE_VALID_CACHED_DATA	1
424 #define	FILE_REGION_USAGE_VALID_NONCACHED_DATA	2
425 #define	FILE_REGION_USAGE_VALID__MASK		3
426 
427 typedef struct _FILE_REGION_INFO {
428 	uint64_t off;
429 	uint64_t len;
430 	uint32_t usage;
431 	uint32_t reserved;
432 } FILE_REGION_INFO;
433 
434 
435 /*
436  * FSCTL_QUERY_FILE_REGIONS
437  *
438  * [MS-FSCC] 2.3.39 FSCTL_QUERY_FILE_REGIONS Request
439  * [MS-FSCC] 2.3.40.1 FILE_REGION_INFO
440  *
441  * Looks like Hyper-V uses this to query the "valid data length",
442  * which to us is the beginning offset of the last "hole".
443  * Similar logic as smb2_sparse_copy()
444  */
445 uint32_t
smb2_fsctl_query_file_regions(smb_request_t * sr,smb_fsctl_t * fsctl)446 smb2_fsctl_query_file_regions(smb_request_t *sr, smb_fsctl_t *fsctl)
447 {
448 	smb_attr_t attr;
449 	cred_t *kcr;
450 	smb_ofile_t *ofile = sr->fid_ofile;
451 	FILE_REGION_INFO arg;
452 	off64_t cur_off, end_off, eof;
453 	off64_t data, hole;
454 	uint32_t tot_regions, put_regions;
455 	uint32_t status;
456 	int rc;
457 
458 	if (fsctl->InputCount == 0) {
459 		arg.off = 0;
460 		arg.len = INT64_MAX;
461 		arg.usage = FILE_REGION_USAGE_VALID_CACHED_DATA;
462 		arg.reserved = 0;
463 	} else {
464 		/* min size check: reserved is optional */
465 		rc = smb_mbc_decodef(fsctl->in_mbc, "qql",
466 		    &arg.off, &arg.len, &arg.usage);
467 		if (rc != 0)
468 			return (NT_STATUS_BUFFER_TOO_SMALL);
469 
470 		/*
471 		 * The given offset and length are int64_t (signed).
472 		 */
473 		if (arg.off > INT64_MAX || arg.len > INT64_MAX)
474 			return (NT_STATUS_INVALID_PARAMETER);
475 		if ((arg.off + arg.len) > INT64_MAX)
476 			return (NT_STATUS_INVALID_PARAMETER);
477 		if ((arg.usage & FILE_REGION_USAGE_VALID__MASK) == 0)
478 			return (NT_STATUS_INVALID_PARAMETER);
479 		arg.reserved = 0;
480 	}
481 
482 	if (fsctl->MaxOutputResp < (16 + sizeof (FILE_REGION_INFO)))
483 		return (NT_STATUS_BUFFER_TOO_SMALL);
484 
485 	if (!smb_node_is_file(ofile->f_node))
486 		return (NT_STATUS_INVALID_PARAMETER);
487 
488 	/*
489 	 * This operation is effectively a read
490 	 */
491 	status = smb_ofile_access(ofile, ofile->f_cr, FILE_READ_DATA);
492 	if (status != NT_STATUS_SUCCESS)
493 		return (status);
494 
495 	/*
496 	 * Need the file size and dosattr
497 	 */
498 	bzero(&attr, sizeof (attr));
499 	attr.sa_mask = SMB_AT_SIZE | SMB_AT_DOSATTR;
500 	kcr = zone_kcred();
501 	status = smb_node_getattr(sr, ofile->f_node, kcr, ofile, &attr);
502 	if (status != NT_STATUS_SUCCESS)
503 		return (status);
504 
505 	cur_off = arg.off;
506 	end_off = arg.off + arg.len;
507 	eof = attr.sa_vattr.va_size;
508 
509 	/*
510 	 * If (InputRegion.FileOffset > Eof) OR
511 	 * ((InputRegion.FileOffset == Eof) AND (Eof > 0)),
512 	 * the operation MUST return STATUS_SUCCESS, with
513 	 * BytesReturned set to 0 (empty data response)
514 	 */
515 	if ((arg.off > eof) || (arg.off == eof && eof > 0))
516 		return (NT_STATUS_SUCCESS);
517 	if (end_off > eof)
518 		end_off = eof;
519 
520 	/*
521 	 * We're going to return at least one region.  Put place-holder
522 	 * data for the fixed part of the response.  Will overwrite this
523 	 * later, when we know how many regions there are and how many
524 	 * of those fit in the allowed response buffer space.  These are:
525 	 * Flags, TotalRegionEntryCount, RegionEntryCount, Reserved
526 	 */
527 	rc = smb_mbc_encodef(fsctl->out_mbc, "llll", 0, 0, 0, 0);
528 	if (rc != 0)
529 		return (NT_STATUS_BUFFER_TOO_SMALL);
530 	tot_regions = put_regions = 0;
531 
532 	/*
533 	 * Get the first pair of (data, hole) offsets at or after
534 	 * the current offset (cur_off).
535 	 */
536 	data = hole = cur_off;
537 	rc = smb_fsop_next_alloc_range(ofile->f_cr,
538 	    ofile->f_node, &data, &hole);
539 	switch (rc) {
540 	case 0:
541 		/* Found (data, hole) */
542 		break;
543 	case ENXIO:
544 		/* No more data after cur_off. */
545 		break;
546 	default:
547 		cmn_err(CE_NOTE, "smb_fsop_next_alloc_range: rc=%d", rc);
548 		/* FALLTHROUGH */
549 	case ENOSYS:	/* FS does not support VOP_IOCTL... */
550 	case ENOTTY:	/* ... or _FIO_SEEK_DATA, _HOLE */
551 		data = cur_off;
552 		hole = eof;
553 		break;
554 	}
555 	DTRACE_PROBE2(range0, uint64_t, data, uint64_t, hole);
556 
557 	/*
558 	 * Only sparse files should present un-allocated regions.
559 	 * If non-sparse, MS-FSA says to just return one region.
560 	 * There still can be a "hole" but only one, starting at
561 	 * "valid data length" (VDL) and ending at end of file.
562 	 * To determine VDL, find the last (data,hole) pair, then
563 	 * VDL is the last "hole" offset.  Note that the above
564 	 * smb_fsop_next_alloc_range may have set data somewhere
565 	 * above cur_off, so we we have to reset that here.
566 	 */
567 	if ((attr.sa_dosattr & FILE_ATTRIBUTE_SPARSE_FILE) == 0) {
568 		/*
569 		 * This works, but it's rather inefficient, and
570 		 * usually just finds VDL==EOF.  Should look into
571 		 * whether there's a faster way to find the VDL.
572 		 */
573 #if 0
574 		off64_t next_data, next_hole;
575 		data = cur_off;
576 		do {
577 			next_data = next_hole = hole;
578 			rc = smb_fsop_next_alloc_range(ofile->f_cr,
579 			    ofile->f_node, &next_data, &next_hole);
580 			if (rc == 0) {
581 				hole = next_hole;
582 			}
583 		} while (rc == 0);
584 #else
585 		/* Assume no "holes" anywhere (VDL==EOF) */
586 		data = cur_off;
587 		hole = eof;
588 #endif
589 		DTRACE_PROBE2(range1, uint64_t, data, uint64_t, hole);
590 	}
591 
592 	/*
593 	 * Loop terminates in the middle, continuing
594 	 * while (cur_off < end_off)
595 	 */
596 	for (;;) {
597 		/*
598 		 * We have a data region that covers (data, hole).
599 		 * It could be partially or entirely beyond the range
600 		 * the caller asked about (if so trim it).
601 		 */
602 		if (hole > end_off)
603 			hole = end_off;
604 		if (data > hole)
605 			data = hole;
606 
607 		/*
608 		 * If cur_off < data encode a "hole" region
609 		 * (cur_off,data) and advance cur_off.
610 		 */
611 		if (cur_off < data) {
612 			rc = smb_mbc_encodef(fsctl->out_mbc, "qqll",
613 			    cur_off,
614 			    (data - cur_off),
615 			    0, // usage (hole)
616 			    0); // reserved
617 			cur_off = data;
618 			if (rc == 0)
619 				put_regions++;
620 			tot_regions++;
621 		}
622 
623 		/*
624 		 * If cur_off < hole encode a "data" region
625 		 * (cur_off,hole) and advance cur_off.
626 		 */
627 		if (cur_off < hole) {
628 			rc = smb_mbc_encodef(fsctl->out_mbc, "qqll",
629 			    cur_off,
630 			    (hole - cur_off),
631 			    FILE_REGION_USAGE_VALID_CACHED_DATA,
632 			    0); // reserved
633 			cur_off = hole;
634 			if (rc == 0)
635 				put_regions++;
636 			tot_regions++;
637 		}
638 
639 		/*
640 		 * Normal loop termination
641 		 */
642 		if (cur_off >= end_off)
643 			break;
644 
645 		/*
646 		 * Get the next region (data, hole) starting on or after
647 		 * the current offset (cur_off).
648 		 */
649 		data = hole = cur_off;
650 		rc = smb_fsop_next_alloc_range(ofile->f_cr,
651 		    ofile->f_node, &data, &hole);
652 		switch (rc) {
653 		case 0:
654 			/* Found (data, hole) */
655 			break;
656 		case ENXIO:
657 			/*
658 			 * No more data after cur_off.
659 			 * Will encode one last hole.
660 			 */
661 			data = hole = eof;
662 			break;
663 		default:
664 			cmn_err(CE_NOTE, "smb_fsop_next_alloc_range: rc=%d",
665 			    rc);
666 			/* FALLTHROUGH */
667 		case ENOSYS:	/* FS does not support VOP_IOCTL... */
668 		case ENOTTY:	/* ... or _FIO_SEEK_DATA, _HOLE */
669 			data = cur_off;
670 			hole = eof;
671 			break;
672 		}
673 		DTRACE_PROBE2(range2, uint64_t, data, uint64_t, hole);
674 	}
675 
676 	/*
677 	 * Overwrite the fixed part of the response with the
678 	 * final numbers of regions etc.
679 	 * Flags, TotalRegionEntryCount, RegionEntryCount, Reserved
680 	 */
681 	(void) smb_mbc_poke(fsctl->out_mbc, 0, "llll",
682 	    0, // flags
683 	    tot_regions,
684 	    put_regions,
685 	    0); // reserved
686 
687 	if (put_regions < tot_regions)
688 		return (NT_STATUS_BUFFER_OVERFLOW);
689 
690 	return (NT_STATUS_SUCCESS);
691 }
692