xref: /openbmc/linux/fs/ocfs2/ioctl.c (revision f7777dcc)
1 /*
2  * linux/fs/ocfs2/ioctl.c
3  *
4  * Copyright (C) 2006 Herbert Poetzl
5  * adapted from Remy Card's ext2/ioctl.c
6  */
7 
8 #include <linux/fs.h>
9 #include <linux/mount.h>
10 #include <linux/compat.h>
11 
12 #include <cluster/masklog.h>
13 
14 #include "ocfs2.h"
15 #include "alloc.h"
16 #include "dlmglue.h"
17 #include "file.h"
18 #include "inode.h"
19 #include "journal.h"
20 
21 #include "ocfs2_fs.h"
22 #include "ioctl.h"
23 #include "resize.h"
24 #include "refcounttree.h"
25 #include "sysfile.h"
26 #include "dir.h"
27 #include "buffer_head_io.h"
28 #include "suballoc.h"
29 #include "move_extents.h"
30 
31 #define o2info_from_user(a, b)	\
32 		copy_from_user(&(a), (b), sizeof(a))
33 #define o2info_to_user(a, b)	\
34 		copy_to_user((typeof(a) __user *)b, &(a), sizeof(a))
35 
36 /*
37  * This call is void because we are already reporting an error that may
38  * be -EFAULT.  The error will be returned from the ioctl(2) call.  It's
39  * just a best-effort to tell userspace that this request caused the error.
40  */
41 static inline void o2info_set_request_error(struct ocfs2_info_request *kreq,
42 					struct ocfs2_info_request __user *req)
43 {
44 	kreq->ir_flags |= OCFS2_INFO_FL_ERROR;
45 	(void)put_user(kreq->ir_flags, (__u32 __user *)&(req->ir_flags));
46 }
47 
48 static inline void o2info_set_request_filled(struct ocfs2_info_request *req)
49 {
50 	req->ir_flags |= OCFS2_INFO_FL_FILLED;
51 }
52 
53 static inline void o2info_clear_request_filled(struct ocfs2_info_request *req)
54 {
55 	req->ir_flags &= ~OCFS2_INFO_FL_FILLED;
56 }
57 
58 static inline int o2info_coherent(struct ocfs2_info_request *req)
59 {
60 	return (!(req->ir_flags & OCFS2_INFO_FL_NON_COHERENT));
61 }
62 
63 static int ocfs2_get_inode_attr(struct inode *inode, unsigned *flags)
64 {
65 	int status;
66 
67 	status = ocfs2_inode_lock(inode, NULL, 0);
68 	if (status < 0) {
69 		mlog_errno(status);
70 		return status;
71 	}
72 	ocfs2_get_inode_flags(OCFS2_I(inode));
73 	*flags = OCFS2_I(inode)->ip_attr;
74 	ocfs2_inode_unlock(inode, 0);
75 
76 	return status;
77 }
78 
79 static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
80 				unsigned mask)
81 {
82 	struct ocfs2_inode_info *ocfs2_inode = OCFS2_I(inode);
83 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
84 	handle_t *handle = NULL;
85 	struct buffer_head *bh = NULL;
86 	unsigned oldflags;
87 	int status;
88 
89 	mutex_lock(&inode->i_mutex);
90 
91 	status = ocfs2_inode_lock(inode, &bh, 1);
92 	if (status < 0) {
93 		mlog_errno(status);
94 		goto bail;
95 	}
96 
97 	status = -EACCES;
98 	if (!inode_owner_or_capable(inode))
99 		goto bail_unlock;
100 
101 	if (!S_ISDIR(inode->i_mode))
102 		flags &= ~OCFS2_DIRSYNC_FL;
103 
104 	oldflags = ocfs2_inode->ip_attr;
105 	flags = flags & mask;
106 	flags |= oldflags & ~mask;
107 
108 	/*
109 	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
110 	 * the relevant capability.
111 	 */
112 	status = -EPERM;
113 	if ((oldflags & OCFS2_IMMUTABLE_FL) || ((flags ^ oldflags) &
114 		(OCFS2_APPEND_FL | OCFS2_IMMUTABLE_FL))) {
115 		if (!capable(CAP_LINUX_IMMUTABLE))
116 			goto bail_unlock;
117 	}
118 
119 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
120 	if (IS_ERR(handle)) {
121 		status = PTR_ERR(handle);
122 		mlog_errno(status);
123 		goto bail_unlock;
124 	}
125 
126 	ocfs2_inode->ip_attr = flags;
127 	ocfs2_set_inode_flags(inode);
128 
129 	status = ocfs2_mark_inode_dirty(handle, inode, bh);
130 	if (status < 0)
131 		mlog_errno(status);
132 
133 	ocfs2_commit_trans(osb, handle);
134 
135 bail_unlock:
136 	ocfs2_inode_unlock(inode, 1);
137 bail:
138 	mutex_unlock(&inode->i_mutex);
139 
140 	brelse(bh);
141 
142 	return status;
143 }
144 
145 int ocfs2_info_handle_blocksize(struct inode *inode,
146 				struct ocfs2_info_request __user *req)
147 {
148 	int status = -EFAULT;
149 	struct ocfs2_info_blocksize oib;
150 
151 	if (o2info_from_user(oib, req))
152 		goto bail;
153 
154 	oib.ib_blocksize = inode->i_sb->s_blocksize;
155 
156 	o2info_set_request_filled(&oib.ib_req);
157 
158 	if (o2info_to_user(oib, req))
159 		goto bail;
160 
161 	status = 0;
162 bail:
163 	if (status)
164 		o2info_set_request_error(&oib.ib_req, req);
165 
166 	return status;
167 }
168 
169 int ocfs2_info_handle_clustersize(struct inode *inode,
170 				  struct ocfs2_info_request __user *req)
171 {
172 	int status = -EFAULT;
173 	struct ocfs2_info_clustersize oic;
174 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
175 
176 	if (o2info_from_user(oic, req))
177 		goto bail;
178 
179 	oic.ic_clustersize = osb->s_clustersize;
180 
181 	o2info_set_request_filled(&oic.ic_req);
182 
183 	if (o2info_to_user(oic, req))
184 		goto bail;
185 
186 	status = 0;
187 bail:
188 	if (status)
189 		o2info_set_request_error(&oic.ic_req, req);
190 
191 	return status;
192 }
193 
194 int ocfs2_info_handle_maxslots(struct inode *inode,
195 			       struct ocfs2_info_request __user *req)
196 {
197 	int status = -EFAULT;
198 	struct ocfs2_info_maxslots oim;
199 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
200 
201 	if (o2info_from_user(oim, req))
202 		goto bail;
203 
204 	oim.im_max_slots = osb->max_slots;
205 
206 	o2info_set_request_filled(&oim.im_req);
207 
208 	if (o2info_to_user(oim, req))
209 		goto bail;
210 
211 	status = 0;
212 bail:
213 	if (status)
214 		o2info_set_request_error(&oim.im_req, req);
215 
216 	return status;
217 }
218 
219 int ocfs2_info_handle_label(struct inode *inode,
220 			    struct ocfs2_info_request __user *req)
221 {
222 	int status = -EFAULT;
223 	struct ocfs2_info_label oil;
224 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
225 
226 	if (o2info_from_user(oil, req))
227 		goto bail;
228 
229 	memcpy(oil.il_label, osb->vol_label, OCFS2_MAX_VOL_LABEL_LEN);
230 
231 	o2info_set_request_filled(&oil.il_req);
232 
233 	if (o2info_to_user(oil, req))
234 		goto bail;
235 
236 	status = 0;
237 bail:
238 	if (status)
239 		o2info_set_request_error(&oil.il_req, req);
240 
241 	return status;
242 }
243 
244 int ocfs2_info_handle_uuid(struct inode *inode,
245 			   struct ocfs2_info_request __user *req)
246 {
247 	int status = -EFAULT;
248 	struct ocfs2_info_uuid oiu;
249 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
250 
251 	if (o2info_from_user(oiu, req))
252 		goto bail;
253 
254 	memcpy(oiu.iu_uuid_str, osb->uuid_str, OCFS2_TEXT_UUID_LEN + 1);
255 
256 	o2info_set_request_filled(&oiu.iu_req);
257 
258 	if (o2info_to_user(oiu, req))
259 		goto bail;
260 
261 	status = 0;
262 bail:
263 	if (status)
264 		o2info_set_request_error(&oiu.iu_req, req);
265 
266 	return status;
267 }
268 
269 int ocfs2_info_handle_fs_features(struct inode *inode,
270 				  struct ocfs2_info_request __user *req)
271 {
272 	int status = -EFAULT;
273 	struct ocfs2_info_fs_features oif;
274 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
275 
276 	if (o2info_from_user(oif, req))
277 		goto bail;
278 
279 	oif.if_compat_features = osb->s_feature_compat;
280 	oif.if_incompat_features = osb->s_feature_incompat;
281 	oif.if_ro_compat_features = osb->s_feature_ro_compat;
282 
283 	o2info_set_request_filled(&oif.if_req);
284 
285 	if (o2info_to_user(oif, req))
286 		goto bail;
287 
288 	status = 0;
289 bail:
290 	if (status)
291 		o2info_set_request_error(&oif.if_req, req);
292 
293 	return status;
294 }
295 
296 int ocfs2_info_handle_journal_size(struct inode *inode,
297 				   struct ocfs2_info_request __user *req)
298 {
299 	int status = -EFAULT;
300 	struct ocfs2_info_journal_size oij;
301 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
302 
303 	if (o2info_from_user(oij, req))
304 		goto bail;
305 
306 	oij.ij_journal_size = i_size_read(osb->journal->j_inode);
307 
308 	o2info_set_request_filled(&oij.ij_req);
309 
310 	if (o2info_to_user(oij, req))
311 		goto bail;
312 
313 	status = 0;
314 bail:
315 	if (status)
316 		o2info_set_request_error(&oij.ij_req, req);
317 
318 	return status;
319 }
320 
321 int ocfs2_info_scan_inode_alloc(struct ocfs2_super *osb,
322 				struct inode *inode_alloc, u64 blkno,
323 				struct ocfs2_info_freeinode *fi, u32 slot)
324 {
325 	int status = 0, unlock = 0;
326 
327 	struct buffer_head *bh = NULL;
328 	struct ocfs2_dinode *dinode_alloc = NULL;
329 
330 	if (inode_alloc)
331 		mutex_lock(&inode_alloc->i_mutex);
332 
333 	if (o2info_coherent(&fi->ifi_req)) {
334 		status = ocfs2_inode_lock(inode_alloc, &bh, 0);
335 		if (status < 0) {
336 			mlog_errno(status);
337 			goto bail;
338 		}
339 		unlock = 1;
340 	} else {
341 		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
342 		if (status < 0) {
343 			mlog_errno(status);
344 			goto bail;
345 		}
346 	}
347 
348 	dinode_alloc = (struct ocfs2_dinode *)bh->b_data;
349 
350 	fi->ifi_stat[slot].lfi_total =
351 		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total);
352 	fi->ifi_stat[slot].lfi_free =
353 		le32_to_cpu(dinode_alloc->id1.bitmap1.i_total) -
354 		le32_to_cpu(dinode_alloc->id1.bitmap1.i_used);
355 
356 bail:
357 	if (unlock)
358 		ocfs2_inode_unlock(inode_alloc, 0);
359 
360 	if (inode_alloc)
361 		mutex_unlock(&inode_alloc->i_mutex);
362 
363 	brelse(bh);
364 
365 	return status;
366 }
367 
368 int ocfs2_info_handle_freeinode(struct inode *inode,
369 				struct ocfs2_info_request __user *req)
370 {
371 	u32 i;
372 	u64 blkno = -1;
373 	char namebuf[40];
374 	int status = -EFAULT, type = INODE_ALLOC_SYSTEM_INODE;
375 	struct ocfs2_info_freeinode *oifi = NULL;
376 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
377 	struct inode *inode_alloc = NULL;
378 
379 	oifi = kzalloc(sizeof(struct ocfs2_info_freeinode), GFP_KERNEL);
380 	if (!oifi) {
381 		status = -ENOMEM;
382 		mlog_errno(status);
383 		goto out_err;
384 	}
385 
386 	if (o2info_from_user(*oifi, req))
387 		goto bail;
388 
389 	oifi->ifi_slotnum = osb->max_slots;
390 
391 	for (i = 0; i < oifi->ifi_slotnum; i++) {
392 		if (o2info_coherent(&oifi->ifi_req)) {
393 			inode_alloc = ocfs2_get_system_file_inode(osb, type, i);
394 			if (!inode_alloc) {
395 				mlog(ML_ERROR, "unable to get alloc inode in "
396 				    "slot %u\n", i);
397 				status = -EIO;
398 				goto bail;
399 			}
400 		} else {
401 			ocfs2_sprintf_system_inode_name(namebuf,
402 							sizeof(namebuf),
403 							type, i);
404 			status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
405 							    namebuf,
406 							    strlen(namebuf),
407 							    &blkno);
408 			if (status < 0) {
409 				status = -ENOENT;
410 				goto bail;
411 			}
412 		}
413 
414 		status = ocfs2_info_scan_inode_alloc(osb, inode_alloc, blkno, oifi, i);
415 		if (status < 0)
416 			goto bail;
417 
418 		iput(inode_alloc);
419 		inode_alloc = NULL;
420 	}
421 
422 	o2info_set_request_filled(&oifi->ifi_req);
423 
424 	if (o2info_to_user(*oifi, req))
425 		goto bail;
426 
427 	status = 0;
428 bail:
429 	if (status)
430 		o2info_set_request_error(&oifi->ifi_req, req);
431 
432 	kfree(oifi);
433 out_err:
434 	return status;
435 }
436 
437 static void o2ffg_update_histogram(struct ocfs2_info_free_chunk_list *hist,
438 				   unsigned int chunksize)
439 {
440 	int index;
441 
442 	index = __ilog2_u32(chunksize);
443 	if (index >= OCFS2_INFO_MAX_HIST)
444 		index = OCFS2_INFO_MAX_HIST - 1;
445 
446 	hist->fc_chunks[index]++;
447 	hist->fc_clusters[index] += chunksize;
448 }
449 
450 static void o2ffg_update_stats(struct ocfs2_info_freefrag_stats *stats,
451 			       unsigned int chunksize)
452 {
453 	if (chunksize > stats->ffs_max)
454 		stats->ffs_max = chunksize;
455 
456 	if (chunksize < stats->ffs_min)
457 		stats->ffs_min = chunksize;
458 
459 	stats->ffs_avg += chunksize;
460 	stats->ffs_free_chunks_real++;
461 }
462 
463 void ocfs2_info_update_ffg(struct ocfs2_info_freefrag *ffg,
464 			   unsigned int chunksize)
465 {
466 	o2ffg_update_histogram(&(ffg->iff_ffs.ffs_fc_hist), chunksize);
467 	o2ffg_update_stats(&(ffg->iff_ffs), chunksize);
468 }
469 
470 int ocfs2_info_freefrag_scan_chain(struct ocfs2_super *osb,
471 				   struct inode *gb_inode,
472 				   struct ocfs2_dinode *gb_dinode,
473 				   struct ocfs2_chain_rec *rec,
474 				   struct ocfs2_info_freefrag *ffg,
475 				   u32 chunks_in_group)
476 {
477 	int status = 0, used;
478 	u64 blkno;
479 
480 	struct buffer_head *bh = NULL;
481 	struct ocfs2_group_desc *bg = NULL;
482 
483 	unsigned int max_bits, num_clusters;
484 	unsigned int offset = 0, cluster, chunk;
485 	unsigned int chunk_free, last_chunksize = 0;
486 
487 	if (!le32_to_cpu(rec->c_free))
488 		goto bail;
489 
490 	do {
491 		if (!bg)
492 			blkno = le64_to_cpu(rec->c_blkno);
493 		else
494 			blkno = le64_to_cpu(bg->bg_next_group);
495 
496 		if (bh) {
497 			brelse(bh);
498 			bh = NULL;
499 		}
500 
501 		if (o2info_coherent(&ffg->iff_req))
502 			status = ocfs2_read_group_descriptor(gb_inode,
503 							     gb_dinode,
504 							     blkno, &bh);
505 		else
506 			status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
507 
508 		if (status < 0) {
509 			mlog(ML_ERROR, "Can't read the group descriptor # "
510 			     "%llu from device.", (unsigned long long)blkno);
511 			status = -EIO;
512 			goto bail;
513 		}
514 
515 		bg = (struct ocfs2_group_desc *)bh->b_data;
516 
517 		if (!le16_to_cpu(bg->bg_free_bits_count))
518 			continue;
519 
520 		max_bits = le16_to_cpu(bg->bg_bits);
521 		offset = 0;
522 
523 		for (chunk = 0; chunk < chunks_in_group; chunk++) {
524 			/*
525 			 * last chunk may be not an entire one.
526 			 */
527 			if ((offset + ffg->iff_chunksize) > max_bits)
528 				num_clusters = max_bits - offset;
529 			else
530 				num_clusters = ffg->iff_chunksize;
531 
532 			chunk_free = 0;
533 			for (cluster = 0; cluster < num_clusters; cluster++) {
534 				used = ocfs2_test_bit(offset,
535 						(unsigned long *)bg->bg_bitmap);
536 				/*
537 				 * - chunk_free counts free clusters in #N chunk.
538 				 * - last_chunksize records the size(in) clusters
539 				 *   for the last real free chunk being counted.
540 				 */
541 				if (!used) {
542 					last_chunksize++;
543 					chunk_free++;
544 				}
545 
546 				if (used && last_chunksize) {
547 					ocfs2_info_update_ffg(ffg,
548 							      last_chunksize);
549 					last_chunksize = 0;
550 				}
551 
552 				offset++;
553 			}
554 
555 			if (chunk_free == ffg->iff_chunksize)
556 				ffg->iff_ffs.ffs_free_chunks++;
557 		}
558 
559 		/*
560 		 * need to update the info for last free chunk.
561 		 */
562 		if (last_chunksize)
563 			ocfs2_info_update_ffg(ffg, last_chunksize);
564 
565 	} while (le64_to_cpu(bg->bg_next_group));
566 
567 bail:
568 	brelse(bh);
569 
570 	return status;
571 }
572 
573 int ocfs2_info_freefrag_scan_bitmap(struct ocfs2_super *osb,
574 				    struct inode *gb_inode, u64 blkno,
575 				    struct ocfs2_info_freefrag *ffg)
576 {
577 	u32 chunks_in_group;
578 	int status = 0, unlock = 0, i;
579 
580 	struct buffer_head *bh = NULL;
581 	struct ocfs2_chain_list *cl = NULL;
582 	struct ocfs2_chain_rec *rec = NULL;
583 	struct ocfs2_dinode *gb_dinode = NULL;
584 
585 	if (gb_inode)
586 		mutex_lock(&gb_inode->i_mutex);
587 
588 	if (o2info_coherent(&ffg->iff_req)) {
589 		status = ocfs2_inode_lock(gb_inode, &bh, 0);
590 		if (status < 0) {
591 			mlog_errno(status);
592 			goto bail;
593 		}
594 		unlock = 1;
595 	} else {
596 		status = ocfs2_read_blocks_sync(osb, blkno, 1, &bh);
597 		if (status < 0) {
598 			mlog_errno(status);
599 			goto bail;
600 		}
601 	}
602 
603 	gb_dinode = (struct ocfs2_dinode *)bh->b_data;
604 	cl = &(gb_dinode->id2.i_chain);
605 
606 	/*
607 	 * Chunksize(in) clusters from userspace should be
608 	 * less than clusters in a group.
609 	 */
610 	if (ffg->iff_chunksize > le16_to_cpu(cl->cl_cpg)) {
611 		status = -EINVAL;
612 		goto bail;
613 	}
614 
615 	memset(&ffg->iff_ffs, 0, sizeof(struct ocfs2_info_freefrag_stats));
616 
617 	ffg->iff_ffs.ffs_min = ~0U;
618 	ffg->iff_ffs.ffs_clusters =
619 			le32_to_cpu(gb_dinode->id1.bitmap1.i_total);
620 	ffg->iff_ffs.ffs_free_clusters = ffg->iff_ffs.ffs_clusters -
621 			le32_to_cpu(gb_dinode->id1.bitmap1.i_used);
622 
623 	chunks_in_group = le16_to_cpu(cl->cl_cpg) / ffg->iff_chunksize + 1;
624 
625 	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i++) {
626 		rec = &(cl->cl_recs[i]);
627 		status = ocfs2_info_freefrag_scan_chain(osb, gb_inode,
628 							gb_dinode,
629 							rec, ffg,
630 							chunks_in_group);
631 		if (status)
632 			goto bail;
633 	}
634 
635 	if (ffg->iff_ffs.ffs_free_chunks_real)
636 		ffg->iff_ffs.ffs_avg = (ffg->iff_ffs.ffs_avg /
637 					ffg->iff_ffs.ffs_free_chunks_real);
638 bail:
639 	if (unlock)
640 		ocfs2_inode_unlock(gb_inode, 0);
641 
642 	if (gb_inode)
643 		mutex_unlock(&gb_inode->i_mutex);
644 
645 	if (gb_inode)
646 		iput(gb_inode);
647 
648 	brelse(bh);
649 
650 	return status;
651 }
652 
653 int ocfs2_info_handle_freefrag(struct inode *inode,
654 			       struct ocfs2_info_request __user *req)
655 {
656 	u64 blkno = -1;
657 	char namebuf[40];
658 	int status = -EFAULT, type = GLOBAL_BITMAP_SYSTEM_INODE;
659 
660 	struct ocfs2_info_freefrag *oiff;
661 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
662 	struct inode *gb_inode = NULL;
663 
664 	oiff = kzalloc(sizeof(struct ocfs2_info_freefrag), GFP_KERNEL);
665 	if (!oiff) {
666 		status = -ENOMEM;
667 		mlog_errno(status);
668 		goto out_err;
669 	}
670 
671 	if (o2info_from_user(*oiff, req))
672 		goto bail;
673 	/*
674 	 * chunksize from userspace should be power of 2.
675 	 */
676 	if ((oiff->iff_chunksize & (oiff->iff_chunksize - 1)) ||
677 	    (!oiff->iff_chunksize)) {
678 		status = -EINVAL;
679 		goto bail;
680 	}
681 
682 	if (o2info_coherent(&oiff->iff_req)) {
683 		gb_inode = ocfs2_get_system_file_inode(osb, type,
684 						       OCFS2_INVALID_SLOT);
685 		if (!gb_inode) {
686 			mlog(ML_ERROR, "unable to get global_bitmap inode\n");
687 			status = -EIO;
688 			goto bail;
689 		}
690 	} else {
691 		ocfs2_sprintf_system_inode_name(namebuf, sizeof(namebuf), type,
692 						OCFS2_INVALID_SLOT);
693 		status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
694 						    namebuf,
695 						    strlen(namebuf),
696 						    &blkno);
697 		if (status < 0) {
698 			status = -ENOENT;
699 			goto bail;
700 		}
701 	}
702 
703 	status = ocfs2_info_freefrag_scan_bitmap(osb, gb_inode, blkno, oiff);
704 	if (status < 0)
705 		goto bail;
706 
707 	o2info_set_request_filled(&oiff->iff_req);
708 
709 	if (o2info_to_user(*oiff, req)) {
710 		status = -EFAULT;
711 		goto bail;
712 	}
713 
714 	status = 0;
715 bail:
716 	if (status)
717 		o2info_set_request_error(&oiff->iff_req, req);
718 
719 	kfree(oiff);
720 out_err:
721 	return status;
722 }
723 
724 int ocfs2_info_handle_unknown(struct inode *inode,
725 			      struct ocfs2_info_request __user *req)
726 {
727 	int status = -EFAULT;
728 	struct ocfs2_info_request oir;
729 
730 	if (o2info_from_user(oir, req))
731 		goto bail;
732 
733 	o2info_clear_request_filled(&oir);
734 
735 	if (o2info_to_user(oir, req))
736 		goto bail;
737 
738 	status = 0;
739 bail:
740 	if (status)
741 		o2info_set_request_error(&oir, req);
742 
743 	return status;
744 }
745 
746 /*
747  * Validate and distinguish OCFS2_IOC_INFO requests.
748  *
749  * - validate the magic number.
750  * - distinguish different requests.
751  * - validate size of different requests.
752  */
753 int ocfs2_info_handle_request(struct inode *inode,
754 			      struct ocfs2_info_request __user *req)
755 {
756 	int status = -EFAULT;
757 	struct ocfs2_info_request oir;
758 
759 	if (o2info_from_user(oir, req))
760 		goto bail;
761 
762 	status = -EINVAL;
763 	if (oir.ir_magic != OCFS2_INFO_MAGIC)
764 		goto bail;
765 
766 	switch (oir.ir_code) {
767 	case OCFS2_INFO_BLOCKSIZE:
768 		if (oir.ir_size == sizeof(struct ocfs2_info_blocksize))
769 			status = ocfs2_info_handle_blocksize(inode, req);
770 		break;
771 	case OCFS2_INFO_CLUSTERSIZE:
772 		if (oir.ir_size == sizeof(struct ocfs2_info_clustersize))
773 			status = ocfs2_info_handle_clustersize(inode, req);
774 		break;
775 	case OCFS2_INFO_MAXSLOTS:
776 		if (oir.ir_size == sizeof(struct ocfs2_info_maxslots))
777 			status = ocfs2_info_handle_maxslots(inode, req);
778 		break;
779 	case OCFS2_INFO_LABEL:
780 		if (oir.ir_size == sizeof(struct ocfs2_info_label))
781 			status = ocfs2_info_handle_label(inode, req);
782 		break;
783 	case OCFS2_INFO_UUID:
784 		if (oir.ir_size == sizeof(struct ocfs2_info_uuid))
785 			status = ocfs2_info_handle_uuid(inode, req);
786 		break;
787 	case OCFS2_INFO_FS_FEATURES:
788 		if (oir.ir_size == sizeof(struct ocfs2_info_fs_features))
789 			status = ocfs2_info_handle_fs_features(inode, req);
790 		break;
791 	case OCFS2_INFO_JOURNAL_SIZE:
792 		if (oir.ir_size == sizeof(struct ocfs2_info_journal_size))
793 			status = ocfs2_info_handle_journal_size(inode, req);
794 		break;
795 	case OCFS2_INFO_FREEINODE:
796 		if (oir.ir_size == sizeof(struct ocfs2_info_freeinode))
797 			status = ocfs2_info_handle_freeinode(inode, req);
798 		break;
799 	case OCFS2_INFO_FREEFRAG:
800 		if (oir.ir_size == sizeof(struct ocfs2_info_freefrag))
801 			status = ocfs2_info_handle_freefrag(inode, req);
802 		break;
803 	default:
804 		status = ocfs2_info_handle_unknown(inode, req);
805 		break;
806 	}
807 
808 bail:
809 	return status;
810 }
811 
812 int ocfs2_get_request_ptr(struct ocfs2_info *info, int idx,
813 			  u64 *req_addr, int compat_flag)
814 {
815 	int status = -EFAULT;
816 	u64 __user *bp = NULL;
817 
818 	if (compat_flag) {
819 #ifdef CONFIG_COMPAT
820 		/*
821 		 * pointer bp stores the base address of a pointers array,
822 		 * which collects all addresses of separate request.
823 		 */
824 		bp = (u64 __user *)(unsigned long)compat_ptr(info->oi_requests);
825 #else
826 		BUG();
827 #endif
828 	} else
829 		bp = (u64 __user *)(unsigned long)(info->oi_requests);
830 
831 	if (o2info_from_user(*req_addr, bp + idx))
832 		goto bail;
833 
834 	status = 0;
835 bail:
836 	return status;
837 }
838 
839 /*
840  * OCFS2_IOC_INFO handles an array of requests passed from userspace.
841  *
842  * ocfs2_info_handle() recevies a large info aggregation, grab and
843  * validate the request count from header, then break it into small
844  * pieces, later specific handlers can handle them one by one.
845  *
846  * Idea here is to make each separate request small enough to ensure
847  * a better backward&forward compatibility, since a small piece of
848  * request will be less likely to be broken if disk layout get changed.
849  */
850 int ocfs2_info_handle(struct inode *inode, struct ocfs2_info *info,
851 		      int compat_flag)
852 {
853 	int i, status = 0;
854 	u64 req_addr;
855 	struct ocfs2_info_request __user *reqp;
856 
857 	if ((info->oi_count > OCFS2_INFO_MAX_REQUEST) ||
858 	    (!info->oi_requests)) {
859 		status = -EINVAL;
860 		goto bail;
861 	}
862 
863 	for (i = 0; i < info->oi_count; i++) {
864 
865 		status = ocfs2_get_request_ptr(info, i, &req_addr, compat_flag);
866 		if (status)
867 			break;
868 
869 		reqp = (struct ocfs2_info_request __user *)(unsigned long)req_addr;
870 		if (!reqp) {
871 			status = -EINVAL;
872 			goto bail;
873 		}
874 
875 		status = ocfs2_info_handle_request(inode, reqp);
876 		if (status)
877 			break;
878 	}
879 
880 bail:
881 	return status;
882 }
883 
884 long ocfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
885 {
886 	struct inode *inode = file_inode(filp);
887 	unsigned int flags;
888 	int new_clusters;
889 	int status;
890 	struct ocfs2_space_resv sr;
891 	struct ocfs2_new_group_input input;
892 	struct reflink_arguments args;
893 	const char __user *old_path;
894 	const char __user *new_path;
895 	bool preserve;
896 	struct ocfs2_info info;
897 	void __user *argp = (void __user *)arg;
898 
899 	switch (cmd) {
900 	case OCFS2_IOC_GETFLAGS:
901 		status = ocfs2_get_inode_attr(inode, &flags);
902 		if (status < 0)
903 			return status;
904 
905 		flags &= OCFS2_FL_VISIBLE;
906 		return put_user(flags, (int __user *) arg);
907 	case OCFS2_IOC_SETFLAGS:
908 		if (get_user(flags, (int __user *) arg))
909 			return -EFAULT;
910 
911 		status = mnt_want_write_file(filp);
912 		if (status)
913 			return status;
914 		status = ocfs2_set_inode_attr(inode, flags,
915 			OCFS2_FL_MODIFIABLE);
916 		mnt_drop_write_file(filp);
917 		return status;
918 	case OCFS2_IOC_RESVSP:
919 	case OCFS2_IOC_RESVSP64:
920 	case OCFS2_IOC_UNRESVSP:
921 	case OCFS2_IOC_UNRESVSP64:
922 		if (copy_from_user(&sr, (int __user *) arg, sizeof(sr)))
923 			return -EFAULT;
924 
925 		return ocfs2_change_file_space(filp, cmd, &sr);
926 	case OCFS2_IOC_GROUP_EXTEND:
927 		if (!capable(CAP_SYS_RESOURCE))
928 			return -EPERM;
929 
930 		if (get_user(new_clusters, (int __user *)arg))
931 			return -EFAULT;
932 
933 		status = mnt_want_write_file(filp);
934 		if (status)
935 			return status;
936 		status = ocfs2_group_extend(inode, new_clusters);
937 		mnt_drop_write_file(filp);
938 		return status;
939 	case OCFS2_IOC_GROUP_ADD:
940 	case OCFS2_IOC_GROUP_ADD64:
941 		if (!capable(CAP_SYS_RESOURCE))
942 			return -EPERM;
943 
944 		if (copy_from_user(&input, (int __user *) arg, sizeof(input)))
945 			return -EFAULT;
946 
947 		status = mnt_want_write_file(filp);
948 		if (status)
949 			return status;
950 		status = ocfs2_group_add(inode, &input);
951 		mnt_drop_write_file(filp);
952 		return status;
953 	case OCFS2_IOC_REFLINK:
954 		if (copy_from_user(&args, argp, sizeof(args)))
955 			return -EFAULT;
956 		old_path = (const char __user *)(unsigned long)args.old_path;
957 		new_path = (const char __user *)(unsigned long)args.new_path;
958 		preserve = (args.preserve != 0);
959 
960 		return ocfs2_reflink_ioctl(inode, old_path, new_path, preserve);
961 	case OCFS2_IOC_INFO:
962 		if (copy_from_user(&info, argp, sizeof(struct ocfs2_info)))
963 			return -EFAULT;
964 
965 		return ocfs2_info_handle(inode, &info, 0);
966 	case FITRIM:
967 	{
968 		struct super_block *sb = inode->i_sb;
969 		struct fstrim_range range;
970 		int ret = 0;
971 
972 		if (!capable(CAP_SYS_ADMIN))
973 			return -EPERM;
974 
975 		if (copy_from_user(&range, argp, sizeof(range)))
976 			return -EFAULT;
977 
978 		ret = ocfs2_trim_fs(sb, &range);
979 		if (ret < 0)
980 			return ret;
981 
982 		if (copy_to_user(argp, &range, sizeof(range)))
983 			return -EFAULT;
984 
985 		return 0;
986 	}
987 	case OCFS2_IOC_MOVE_EXT:
988 		return ocfs2_ioctl_move_extents(filp, argp);
989 	default:
990 		return -ENOTTY;
991 	}
992 }
993 
994 #ifdef CONFIG_COMPAT
995 long ocfs2_compat_ioctl(struct file *file, unsigned cmd, unsigned long arg)
996 {
997 	bool preserve;
998 	struct reflink_arguments args;
999 	struct inode *inode = file_inode(file);
1000 	struct ocfs2_info info;
1001 	void __user *argp = (void __user *)arg;
1002 
1003 	switch (cmd) {
1004 	case OCFS2_IOC32_GETFLAGS:
1005 		cmd = OCFS2_IOC_GETFLAGS;
1006 		break;
1007 	case OCFS2_IOC32_SETFLAGS:
1008 		cmd = OCFS2_IOC_SETFLAGS;
1009 		break;
1010 	case OCFS2_IOC_RESVSP:
1011 	case OCFS2_IOC_RESVSP64:
1012 	case OCFS2_IOC_UNRESVSP:
1013 	case OCFS2_IOC_UNRESVSP64:
1014 	case OCFS2_IOC_GROUP_EXTEND:
1015 	case OCFS2_IOC_GROUP_ADD:
1016 	case OCFS2_IOC_GROUP_ADD64:
1017 	case FITRIM:
1018 		break;
1019 	case OCFS2_IOC_REFLINK:
1020 		if (copy_from_user(&args, argp, sizeof(args)))
1021 			return -EFAULT;
1022 		preserve = (args.preserve != 0);
1023 
1024 		return ocfs2_reflink_ioctl(inode, compat_ptr(args.old_path),
1025 					   compat_ptr(args.new_path), preserve);
1026 	case OCFS2_IOC_INFO:
1027 		if (copy_from_user(&info, argp, sizeof(struct ocfs2_info)))
1028 			return -EFAULT;
1029 
1030 		return ocfs2_info_handle(inode, &info, 1);
1031 	case OCFS2_IOC_MOVE_EXT:
1032 		break;
1033 	default:
1034 		return -ENOIOCTLCMD;
1035 	}
1036 
1037 	return ocfs2_ioctl(file, cmd, arg);
1038 }
1039 #endif
1040