xref: /linux/fs/xfs/xfs_super.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 
7 #include "xfs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_sb.h"
13 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_btree.h"
16 #include "xfs_bmap.h"
17 #include "xfs_alloc.h"
18 #include "xfs_fsops.h"
19 #include "xfs_trans.h"
20 #include "xfs_buf_item.h"
21 #include "xfs_log.h"
22 #include "xfs_log_priv.h"
23 #include "xfs_dir2.h"
24 #include "xfs_extfree_item.h"
25 #include "xfs_mru_cache.h"
26 #include "xfs_inode_item.h"
27 #include "xfs_icache.h"
28 #include "xfs_trace.h"
29 #include "xfs_icreate_item.h"
30 #include "xfs_filestream.h"
31 #include "xfs_quota.h"
32 #include "xfs_sysfs.h"
33 #include "xfs_ondisk.h"
34 #include "xfs_rmap_item.h"
35 #include "xfs_refcount_item.h"
36 #include "xfs_bmap_item.h"
37 #include "xfs_reflink.h"
38 #include "xfs_pwork.h"
39 
40 #include <linux/magic.h>
41 #include <linux/fs_context.h>
42 #include <linux/fs_parser.h>
43 
44 static const struct super_operations xfs_super_operations;
45 
46 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
47 #ifdef DEBUG
48 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
49 #endif
50 
51 enum xfs_dax_mode {
52 	XFS_DAX_INODE = 0,
53 	XFS_DAX_ALWAYS = 1,
54 	XFS_DAX_NEVER = 2,
55 };
56 
57 static void
58 xfs_mount_set_dax_mode(
59 	struct xfs_mount	*mp,
60 	enum xfs_dax_mode	mode)
61 {
62 	switch (mode) {
63 	case XFS_DAX_INODE:
64 		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
65 		break;
66 	case XFS_DAX_ALWAYS:
67 		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
68 		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
69 		break;
70 	case XFS_DAX_NEVER:
71 		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
72 		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
73 		break;
74 	}
75 }
76 
77 static const struct constant_table dax_param_enums[] = {
78 	{"inode",	XFS_DAX_INODE },
79 	{"always",	XFS_DAX_ALWAYS },
80 	{"never",	XFS_DAX_NEVER },
81 	{}
82 };
83 
84 /*
85  * Table driven mount option parser.
86  */
87 enum {
88 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
89 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
90 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
91 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
92 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
93 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
94 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
95 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
96 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
97 };
98 
99 static const struct fs_parameter_spec xfs_fs_parameters[] = {
100 	fsparam_u32("logbufs",		Opt_logbufs),
101 	fsparam_string("logbsize",	Opt_logbsize),
102 	fsparam_string("logdev",	Opt_logdev),
103 	fsparam_string("rtdev",		Opt_rtdev),
104 	fsparam_flag("wsync",		Opt_wsync),
105 	fsparam_flag("noalign",		Opt_noalign),
106 	fsparam_flag("swalloc",		Opt_swalloc),
107 	fsparam_u32("sunit",		Opt_sunit),
108 	fsparam_u32("swidth",		Opt_swidth),
109 	fsparam_flag("nouuid",		Opt_nouuid),
110 	fsparam_flag("grpid",		Opt_grpid),
111 	fsparam_flag("nogrpid",		Opt_nogrpid),
112 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
113 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
114 	fsparam_string("allocsize",	Opt_allocsize),
115 	fsparam_flag("norecovery",	Opt_norecovery),
116 	fsparam_flag("inode64",		Opt_inode64),
117 	fsparam_flag("inode32",		Opt_inode32),
118 	fsparam_flag("ikeep",		Opt_ikeep),
119 	fsparam_flag("noikeep",		Opt_noikeep),
120 	fsparam_flag("largeio",		Opt_largeio),
121 	fsparam_flag("nolargeio",	Opt_nolargeio),
122 	fsparam_flag("attr2",		Opt_attr2),
123 	fsparam_flag("noattr2",		Opt_noattr2),
124 	fsparam_flag("filestreams",	Opt_filestreams),
125 	fsparam_flag("quota",		Opt_quota),
126 	fsparam_flag("noquota",		Opt_noquota),
127 	fsparam_flag("usrquota",	Opt_usrquota),
128 	fsparam_flag("grpquota",	Opt_grpquota),
129 	fsparam_flag("prjquota",	Opt_prjquota),
130 	fsparam_flag("uquota",		Opt_uquota),
131 	fsparam_flag("gquota",		Opt_gquota),
132 	fsparam_flag("pquota",		Opt_pquota),
133 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
134 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
135 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
136 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
137 	fsparam_flag("discard",		Opt_discard),
138 	fsparam_flag("nodiscard",	Opt_nodiscard),
139 	fsparam_flag("dax",		Opt_dax),
140 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
141 	{}
142 };
143 
144 struct proc_xfs_info {
145 	uint64_t	flag;
146 	char		*str;
147 };
148 
149 static int
150 xfs_fs_show_options(
151 	struct seq_file		*m,
152 	struct dentry		*root)
153 {
154 	static struct proc_xfs_info xfs_info_set[] = {
155 		/* the few simple ones we can get from the mount struct */
156 		{ XFS_MOUNT_IKEEP,		",ikeep" },
157 		{ XFS_MOUNT_WSYNC,		",wsync" },
158 		{ XFS_MOUNT_NOALIGN,		",noalign" },
159 		{ XFS_MOUNT_SWALLOC,		",swalloc" },
160 		{ XFS_MOUNT_NOUUID,		",nouuid" },
161 		{ XFS_MOUNT_NORECOVERY,		",norecovery" },
162 		{ XFS_MOUNT_ATTR2,		",attr2" },
163 		{ XFS_MOUNT_FILESTREAMS,	",filestreams" },
164 		{ XFS_MOUNT_GRPID,		",grpid" },
165 		{ XFS_MOUNT_DISCARD,		",discard" },
166 		{ XFS_MOUNT_LARGEIO,		",largeio" },
167 		{ XFS_MOUNT_DAX_ALWAYS,		",dax=always" },
168 		{ XFS_MOUNT_DAX_NEVER,		",dax=never" },
169 		{ 0, NULL }
170 	};
171 	struct xfs_mount	*mp = XFS_M(root->d_sb);
172 	struct proc_xfs_info	*xfs_infop;
173 
174 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
175 		if (mp->m_flags & xfs_infop->flag)
176 			seq_puts(m, xfs_infop->str);
177 	}
178 
179 	seq_printf(m, ",inode%d",
180 		(mp->m_flags & XFS_MOUNT_SMALL_INUMS) ? 32 : 64);
181 
182 	if (mp->m_flags & XFS_MOUNT_ALLOCSIZE)
183 		seq_printf(m, ",allocsize=%dk",
184 			   (1 << mp->m_allocsize_log) >> 10);
185 
186 	if (mp->m_logbufs > 0)
187 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
188 	if (mp->m_logbsize > 0)
189 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
190 
191 	if (mp->m_logname)
192 		seq_show_option(m, "logdev", mp->m_logname);
193 	if (mp->m_rtname)
194 		seq_show_option(m, "rtdev", mp->m_rtname);
195 
196 	if (mp->m_dalign > 0)
197 		seq_printf(m, ",sunit=%d",
198 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
199 	if (mp->m_swidth > 0)
200 		seq_printf(m, ",swidth=%d",
201 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
202 
203 	if (mp->m_qflags & XFS_UQUOTA_ACCT) {
204 		if (mp->m_qflags & XFS_UQUOTA_ENFD)
205 			seq_puts(m, ",usrquota");
206 		else
207 			seq_puts(m, ",uqnoenforce");
208 	}
209 
210 	if (mp->m_qflags & XFS_PQUOTA_ACCT) {
211 		if (mp->m_qflags & XFS_PQUOTA_ENFD)
212 			seq_puts(m, ",prjquota");
213 		else
214 			seq_puts(m, ",pqnoenforce");
215 	}
216 	if (mp->m_qflags & XFS_GQUOTA_ACCT) {
217 		if (mp->m_qflags & XFS_GQUOTA_ENFD)
218 			seq_puts(m, ",grpquota");
219 		else
220 			seq_puts(m, ",gqnoenforce");
221 	}
222 
223 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
224 		seq_puts(m, ",noquota");
225 
226 	return 0;
227 }
228 
229 /*
230  * Set parameters for inode allocation heuristics, taking into account
231  * filesystem size and inode32/inode64 mount options; i.e. specifically
232  * whether or not XFS_MOUNT_SMALL_INUMS is set.
233  *
234  * Inode allocation patterns are altered only if inode32 is requested
235  * (XFS_MOUNT_SMALL_INUMS), and the filesystem is sufficiently large.
236  * If altered, XFS_MOUNT_32BITINODES is set as well.
237  *
238  * An agcount independent of that in the mount structure is provided
239  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
240  * to the potentially higher ag count.
241  *
242  * Returns the maximum AG index which may contain inodes.
243  */
244 xfs_agnumber_t
245 xfs_set_inode_alloc(
246 	struct xfs_mount *mp,
247 	xfs_agnumber_t	agcount)
248 {
249 	xfs_agnumber_t	index;
250 	xfs_agnumber_t	maxagi = 0;
251 	xfs_sb_t	*sbp = &mp->m_sb;
252 	xfs_agnumber_t	max_metadata;
253 	xfs_agino_t	agino;
254 	xfs_ino_t	ino;
255 
256 	/*
257 	 * Calculate how much should be reserved for inodes to meet
258 	 * the max inode percentage.  Used only for inode32.
259 	 */
260 	if (M_IGEO(mp)->maxicount) {
261 		uint64_t	icount;
262 
263 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
264 		do_div(icount, 100);
265 		icount += sbp->sb_agblocks - 1;
266 		do_div(icount, sbp->sb_agblocks);
267 		max_metadata = icount;
268 	} else {
269 		max_metadata = agcount;
270 	}
271 
272 	/* Get the last possible inode in the filesystem */
273 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
274 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
275 
276 	/*
277 	 * If user asked for no more than 32-bit inodes, and the fs is
278 	 * sufficiently large, set XFS_MOUNT_32BITINODES if we must alter
279 	 * the allocator to accommodate the request.
280 	 */
281 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > XFS_MAXINUMBER_32)
282 		mp->m_flags |= XFS_MOUNT_32BITINODES;
283 	else
284 		mp->m_flags &= ~XFS_MOUNT_32BITINODES;
285 
286 	for (index = 0; index < agcount; index++) {
287 		struct xfs_perag	*pag;
288 
289 		ino = XFS_AGINO_TO_INO(mp, index, agino);
290 
291 		pag = xfs_perag_get(mp, index);
292 
293 		if (mp->m_flags & XFS_MOUNT_32BITINODES) {
294 			if (ino > XFS_MAXINUMBER_32) {
295 				pag->pagi_inodeok = 0;
296 				pag->pagf_metadata = 0;
297 			} else {
298 				pag->pagi_inodeok = 1;
299 				maxagi++;
300 				if (index < max_metadata)
301 					pag->pagf_metadata = 1;
302 				else
303 					pag->pagf_metadata = 0;
304 			}
305 		} else {
306 			pag->pagi_inodeok = 1;
307 			pag->pagf_metadata = 0;
308 		}
309 
310 		xfs_perag_put(pag);
311 	}
312 
313 	return (mp->m_flags & XFS_MOUNT_32BITINODES) ? maxagi : agcount;
314 }
315 
316 STATIC int
317 xfs_blkdev_get(
318 	xfs_mount_t		*mp,
319 	const char		*name,
320 	struct block_device	**bdevp)
321 {
322 	int			error = 0;
323 
324 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
325 				    mp);
326 	if (IS_ERR(*bdevp)) {
327 		error = PTR_ERR(*bdevp);
328 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
329 	}
330 
331 	return error;
332 }
333 
334 STATIC void
335 xfs_blkdev_put(
336 	struct block_device	*bdev)
337 {
338 	if (bdev)
339 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
340 }
341 
342 void
343 xfs_blkdev_issue_flush(
344 	xfs_buftarg_t		*buftarg)
345 {
346 	blkdev_issue_flush(buftarg->bt_bdev);
347 }
348 
349 STATIC void
350 xfs_close_devices(
351 	struct xfs_mount	*mp)
352 {
353 	struct dax_device *dax_ddev = mp->m_ddev_targp->bt_daxdev;
354 
355 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
356 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
357 		struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev;
358 
359 		xfs_free_buftarg(mp->m_logdev_targp);
360 		xfs_blkdev_put(logdev);
361 		fs_put_dax(dax_logdev);
362 	}
363 	if (mp->m_rtdev_targp) {
364 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
365 		struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev;
366 
367 		xfs_free_buftarg(mp->m_rtdev_targp);
368 		xfs_blkdev_put(rtdev);
369 		fs_put_dax(dax_rtdev);
370 	}
371 	xfs_free_buftarg(mp->m_ddev_targp);
372 	fs_put_dax(dax_ddev);
373 }
374 
375 /*
376  * The file system configurations are:
377  *	(1) device (partition) with data and internal log
378  *	(2) logical volume with data and log subvolumes.
379  *	(3) logical volume with data, log, and realtime subvolumes.
380  *
381  * We only have to handle opening the log and realtime volumes here if
382  * they are present.  The data subvolume has already been opened by
383  * get_sb_bdev() and is stored in sb->s_bdev.
384  */
385 STATIC int
386 xfs_open_devices(
387 	struct xfs_mount	*mp)
388 {
389 	struct block_device	*ddev = mp->m_super->s_bdev;
390 	struct dax_device	*dax_ddev = fs_dax_get_by_bdev(ddev);
391 	struct dax_device	*dax_logdev = NULL, *dax_rtdev = NULL;
392 	struct block_device	*logdev = NULL, *rtdev = NULL;
393 	int			error;
394 
395 	/*
396 	 * Open real time and log devices - order is important.
397 	 */
398 	if (mp->m_logname) {
399 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
400 		if (error)
401 			goto out;
402 		dax_logdev = fs_dax_get_by_bdev(logdev);
403 	}
404 
405 	if (mp->m_rtname) {
406 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
407 		if (error)
408 			goto out_close_logdev;
409 
410 		if (rtdev == ddev || rtdev == logdev) {
411 			xfs_warn(mp,
412 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
413 			error = -EINVAL;
414 			goto out_close_rtdev;
415 		}
416 		dax_rtdev = fs_dax_get_by_bdev(rtdev);
417 	}
418 
419 	/*
420 	 * Setup xfs_mount buffer target pointers
421 	 */
422 	error = -ENOMEM;
423 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev);
424 	if (!mp->m_ddev_targp)
425 		goto out_close_rtdev;
426 
427 	if (rtdev) {
428 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev);
429 		if (!mp->m_rtdev_targp)
430 			goto out_free_ddev_targ;
431 	}
432 
433 	if (logdev && logdev != ddev) {
434 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev);
435 		if (!mp->m_logdev_targp)
436 			goto out_free_rtdev_targ;
437 	} else {
438 		mp->m_logdev_targp = mp->m_ddev_targp;
439 	}
440 
441 	return 0;
442 
443  out_free_rtdev_targ:
444 	if (mp->m_rtdev_targp)
445 		xfs_free_buftarg(mp->m_rtdev_targp);
446  out_free_ddev_targ:
447 	xfs_free_buftarg(mp->m_ddev_targp);
448  out_close_rtdev:
449 	xfs_blkdev_put(rtdev);
450 	fs_put_dax(dax_rtdev);
451  out_close_logdev:
452 	if (logdev && logdev != ddev) {
453 		xfs_blkdev_put(logdev);
454 		fs_put_dax(dax_logdev);
455 	}
456  out:
457 	fs_put_dax(dax_ddev);
458 	return error;
459 }
460 
461 /*
462  * Setup xfs_mount buffer target pointers based on superblock
463  */
464 STATIC int
465 xfs_setup_devices(
466 	struct xfs_mount	*mp)
467 {
468 	int			error;
469 
470 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
471 	if (error)
472 		return error;
473 
474 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
475 		unsigned int	log_sector_size = BBSIZE;
476 
477 		if (xfs_sb_version_hassector(&mp->m_sb))
478 			log_sector_size = mp->m_sb.sb_logsectsize;
479 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
480 					    log_sector_size);
481 		if (error)
482 			return error;
483 	}
484 	if (mp->m_rtdev_targp) {
485 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
486 					    mp->m_sb.sb_sectsize);
487 		if (error)
488 			return error;
489 	}
490 
491 	return 0;
492 }
493 
494 STATIC int
495 xfs_init_mount_workqueues(
496 	struct xfs_mount	*mp)
497 {
498 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
499 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
500 			1, mp->m_super->s_id);
501 	if (!mp->m_buf_workqueue)
502 		goto out;
503 
504 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
505 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
506 			0, mp->m_super->s_id);
507 	if (!mp->m_unwritten_workqueue)
508 		goto out_destroy_buf;
509 
510 	mp->m_cil_workqueue = alloc_workqueue("xfs-cil/%s",
511 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM | WQ_UNBOUND),
512 			0, mp->m_super->s_id);
513 	if (!mp->m_cil_workqueue)
514 		goto out_destroy_unwritten;
515 
516 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
517 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
518 			0, mp->m_super->s_id);
519 	if (!mp->m_reclaim_workqueue)
520 		goto out_destroy_cil;
521 
522 	mp->m_gc_workqueue = alloc_workqueue("xfs-gc/%s",
523 			WQ_SYSFS | WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM,
524 			0, mp->m_super->s_id);
525 	if (!mp->m_gc_workqueue)
526 		goto out_destroy_reclaim;
527 
528 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
529 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
530 	if (!mp->m_sync_workqueue)
531 		goto out_destroy_eofb;
532 
533 	return 0;
534 
535 out_destroy_eofb:
536 	destroy_workqueue(mp->m_gc_workqueue);
537 out_destroy_reclaim:
538 	destroy_workqueue(mp->m_reclaim_workqueue);
539 out_destroy_cil:
540 	destroy_workqueue(mp->m_cil_workqueue);
541 out_destroy_unwritten:
542 	destroy_workqueue(mp->m_unwritten_workqueue);
543 out_destroy_buf:
544 	destroy_workqueue(mp->m_buf_workqueue);
545 out:
546 	return -ENOMEM;
547 }
548 
549 STATIC void
550 xfs_destroy_mount_workqueues(
551 	struct xfs_mount	*mp)
552 {
553 	destroy_workqueue(mp->m_sync_workqueue);
554 	destroy_workqueue(mp->m_gc_workqueue);
555 	destroy_workqueue(mp->m_reclaim_workqueue);
556 	destroy_workqueue(mp->m_cil_workqueue);
557 	destroy_workqueue(mp->m_unwritten_workqueue);
558 	destroy_workqueue(mp->m_buf_workqueue);
559 }
560 
561 static void
562 xfs_flush_inodes_worker(
563 	struct work_struct	*work)
564 {
565 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
566 						   m_flush_inodes_work);
567 	struct super_block	*sb = mp->m_super;
568 
569 	if (down_read_trylock(&sb->s_umount)) {
570 		sync_inodes_sb(sb);
571 		up_read(&sb->s_umount);
572 	}
573 }
574 
575 /*
576  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
577  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
578  * for IO to complete so that we effectively throttle multiple callers to the
579  * rate at which IO is completing.
580  */
581 void
582 xfs_flush_inodes(
583 	struct xfs_mount	*mp)
584 {
585 	/*
586 	 * If flush_work() returns true then that means we waited for a flush
587 	 * which was already in progress.  Don't bother running another scan.
588 	 */
589 	if (flush_work(&mp->m_flush_inodes_work))
590 		return;
591 
592 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
593 	flush_work(&mp->m_flush_inodes_work);
594 }
595 
596 /* Catch misguided souls that try to use this interface on XFS */
597 STATIC struct inode *
598 xfs_fs_alloc_inode(
599 	struct super_block	*sb)
600 {
601 	BUG();
602 	return NULL;
603 }
604 
605 #ifdef DEBUG
606 static void
607 xfs_check_delalloc(
608 	struct xfs_inode	*ip,
609 	int			whichfork)
610 {
611 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
612 	struct xfs_bmbt_irec	got;
613 	struct xfs_iext_cursor	icur;
614 
615 	if (!ifp || !xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got))
616 		return;
617 	do {
618 		if (isnullstartblock(got.br_startblock)) {
619 			xfs_warn(ip->i_mount,
620 	"ino %llx %s fork has delalloc extent at [0x%llx:0x%llx]",
621 				ip->i_ino,
622 				whichfork == XFS_DATA_FORK ? "data" : "cow",
623 				got.br_startoff, got.br_blockcount);
624 		}
625 	} while (xfs_iext_next_extent(ifp, &icur, &got));
626 }
627 #else
628 #define xfs_check_delalloc(ip, whichfork)	do { } while (0)
629 #endif
630 
631 /*
632  * Now that the generic code is guaranteed not to be accessing
633  * the linux inode, we can inactivate and reclaim the inode.
634  */
635 STATIC void
636 xfs_fs_destroy_inode(
637 	struct inode		*inode)
638 {
639 	struct xfs_inode	*ip = XFS_I(inode);
640 
641 	trace_xfs_destroy_inode(ip);
642 
643 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
644 	XFS_STATS_INC(ip->i_mount, vn_rele);
645 	XFS_STATS_INC(ip->i_mount, vn_remove);
646 
647 	xfs_inactive(ip);
648 
649 	if (!XFS_FORCED_SHUTDOWN(ip->i_mount) && ip->i_delayed_blks) {
650 		xfs_check_delalloc(ip, XFS_DATA_FORK);
651 		xfs_check_delalloc(ip, XFS_COW_FORK);
652 		ASSERT(0);
653 	}
654 
655 	XFS_STATS_INC(ip->i_mount, vn_reclaim);
656 
657 	/*
658 	 * We should never get here with one of the reclaim flags already set.
659 	 */
660 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIMABLE));
661 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIM));
662 
663 	/*
664 	 * We always use background reclaim here because even if the inode is
665 	 * clean, it still may be under IO and hence we have wait for IO
666 	 * completion to occur before we can reclaim the inode. The background
667 	 * reclaim path handles this more efficiently than we can here, so
668 	 * simply let background reclaim tear down all inodes.
669 	 */
670 	xfs_inode_set_reclaim_tag(ip);
671 }
672 
673 static void
674 xfs_fs_dirty_inode(
675 	struct inode			*inode,
676 	int				flag)
677 {
678 	struct xfs_inode		*ip = XFS_I(inode);
679 	struct xfs_mount		*mp = ip->i_mount;
680 	struct xfs_trans		*tp;
681 
682 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
683 		return;
684 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
685 		return;
686 
687 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
688 		return;
689 	xfs_ilock(ip, XFS_ILOCK_EXCL);
690 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
691 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
692 	xfs_trans_commit(tp);
693 }
694 
695 /*
696  * Slab object creation initialisation for the XFS inode.
697  * This covers only the idempotent fields in the XFS inode;
698  * all other fields need to be initialised on allocation
699  * from the slab. This avoids the need to repeatedly initialise
700  * fields in the xfs inode that left in the initialise state
701  * when freeing the inode.
702  */
703 STATIC void
704 xfs_fs_inode_init_once(
705 	void			*inode)
706 {
707 	struct xfs_inode	*ip = inode;
708 
709 	memset(ip, 0, sizeof(struct xfs_inode));
710 
711 	/* vfs inode */
712 	inode_init_once(VFS_I(ip));
713 
714 	/* xfs inode */
715 	atomic_set(&ip->i_pincount, 0);
716 	spin_lock_init(&ip->i_flags_lock);
717 
718 	mrlock_init(&ip->i_mmaplock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
719 		     "xfsino", ip->i_ino);
720 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
721 		     "xfsino", ip->i_ino);
722 }
723 
724 /*
725  * We do an unlocked check for XFS_IDONTCACHE here because we are already
726  * serialised against cache hits here via the inode->i_lock and igrab() in
727  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
728  * racing with us, and it avoids needing to grab a spinlock here for every inode
729  * we drop the final reference on.
730  */
731 STATIC int
732 xfs_fs_drop_inode(
733 	struct inode		*inode)
734 {
735 	struct xfs_inode	*ip = XFS_I(inode);
736 
737 	/*
738 	 * If this unlinked inode is in the middle of recovery, don't
739 	 * drop the inode just yet; log recovery will take care of
740 	 * that.  See the comment for this inode flag.
741 	 */
742 	if (ip->i_flags & XFS_IRECOVERY) {
743 		ASSERT(ip->i_mount->m_log->l_flags & XLOG_RECOVERY_NEEDED);
744 		return 0;
745 	}
746 
747 	return generic_drop_inode(inode);
748 }
749 
750 static void
751 xfs_mount_free(
752 	struct xfs_mount	*mp)
753 {
754 	kfree(mp->m_rtname);
755 	kfree(mp->m_logname);
756 	kmem_free(mp);
757 }
758 
759 STATIC int
760 xfs_fs_sync_fs(
761 	struct super_block	*sb,
762 	int			wait)
763 {
764 	struct xfs_mount	*mp = XFS_M(sb);
765 
766 	/*
767 	 * Doing anything during the async pass would be counterproductive.
768 	 */
769 	if (!wait)
770 		return 0;
771 
772 	xfs_log_force(mp, XFS_LOG_SYNC);
773 	if (laptop_mode) {
774 		/*
775 		 * The disk must be active because we're syncing.
776 		 * We schedule log work now (now that the disk is
777 		 * active) instead of later (when it might not be).
778 		 */
779 		flush_delayed_work(&mp->m_log->l_work);
780 	}
781 
782 	return 0;
783 }
784 
785 STATIC int
786 xfs_fs_statfs(
787 	struct dentry		*dentry,
788 	struct kstatfs		*statp)
789 {
790 	struct xfs_mount	*mp = XFS_M(dentry->d_sb);
791 	xfs_sb_t		*sbp = &mp->m_sb;
792 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
793 	uint64_t		fakeinos, id;
794 	uint64_t		icount;
795 	uint64_t		ifree;
796 	uint64_t		fdblocks;
797 	xfs_extlen_t		lsize;
798 	int64_t			ffree;
799 
800 	statp->f_type = XFS_SUPER_MAGIC;
801 	statp->f_namelen = MAXNAMELEN - 1;
802 
803 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
804 	statp->f_fsid = u64_to_fsid(id);
805 
806 	icount = percpu_counter_sum(&mp->m_icount);
807 	ifree = percpu_counter_sum(&mp->m_ifree);
808 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
809 
810 	spin_lock(&mp->m_sb_lock);
811 	statp->f_bsize = sbp->sb_blocksize;
812 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
813 	statp->f_blocks = sbp->sb_dblocks - lsize;
814 	spin_unlock(&mp->m_sb_lock);
815 
816 	/* make sure statp->f_bfree does not underflow */
817 	statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0);
818 	statp->f_bavail = statp->f_bfree;
819 
820 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
821 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
822 	if (M_IGEO(mp)->maxicount)
823 		statp->f_files = min_t(typeof(statp->f_files),
824 					statp->f_files,
825 					M_IGEO(mp)->maxicount);
826 
827 	/* If sb_icount overshot maxicount, report actual allocation */
828 	statp->f_files = max_t(typeof(statp->f_files),
829 					statp->f_files,
830 					sbp->sb_icount);
831 
832 	/* make sure statp->f_ffree does not underflow */
833 	ffree = statp->f_files - (icount - ifree);
834 	statp->f_ffree = max_t(int64_t, ffree, 0);
835 
836 
837 	if ((ip->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
838 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
839 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
840 		xfs_qm_statvfs(ip, statp);
841 
842 	if (XFS_IS_REALTIME_MOUNT(mp) &&
843 	    (ip->i_diflags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
844 		statp->f_blocks = sbp->sb_rblocks;
845 		statp->f_bavail = statp->f_bfree =
846 			sbp->sb_frextents * sbp->sb_rextsize;
847 	}
848 
849 	return 0;
850 }
851 
852 STATIC void
853 xfs_save_resvblks(struct xfs_mount *mp)
854 {
855 	uint64_t resblks = 0;
856 
857 	mp->m_resblks_save = mp->m_resblks;
858 	xfs_reserve_blocks(mp, &resblks, NULL);
859 }
860 
861 STATIC void
862 xfs_restore_resvblks(struct xfs_mount *mp)
863 {
864 	uint64_t resblks;
865 
866 	if (mp->m_resblks_save) {
867 		resblks = mp->m_resblks_save;
868 		mp->m_resblks_save = 0;
869 	} else
870 		resblks = xfs_default_resblks(mp);
871 
872 	xfs_reserve_blocks(mp, &resblks, NULL);
873 }
874 
875 /*
876  * Second stage of a freeze. The data is already frozen so we only
877  * need to take care of the metadata. Once that's done sync the superblock
878  * to the log to dirty it in case of a crash while frozen. This ensures that we
879  * will recover the unlinked inode lists on the next mount.
880  */
881 STATIC int
882 xfs_fs_freeze(
883 	struct super_block	*sb)
884 {
885 	struct xfs_mount	*mp = XFS_M(sb);
886 	unsigned int		flags;
887 	int			ret;
888 
889 	/*
890 	 * The filesystem is now frozen far enough that memory reclaim
891 	 * cannot safely operate on the filesystem. Hence we need to
892 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
893 	 */
894 	flags = memalloc_nofs_save();
895 	xfs_blockgc_stop(mp);
896 	xfs_save_resvblks(mp);
897 	ret = xfs_log_quiesce(mp);
898 	memalloc_nofs_restore(flags);
899 	return ret;
900 }
901 
902 STATIC int
903 xfs_fs_unfreeze(
904 	struct super_block	*sb)
905 {
906 	struct xfs_mount	*mp = XFS_M(sb);
907 
908 	xfs_restore_resvblks(mp);
909 	xfs_log_work_queue(mp);
910 	xfs_blockgc_start(mp);
911 	return 0;
912 }
913 
914 /*
915  * This function fills in xfs_mount_t fields based on mount args.
916  * Note: the superblock _has_ now been read in.
917  */
918 STATIC int
919 xfs_finish_flags(
920 	struct xfs_mount	*mp)
921 {
922 	int			ronly = (mp->m_flags & XFS_MOUNT_RDONLY);
923 
924 	/* Fail a mount where the logbuf is smaller than the log stripe */
925 	if (xfs_sb_version_haslogv2(&mp->m_sb)) {
926 		if (mp->m_logbsize <= 0 &&
927 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
928 			mp->m_logbsize = mp->m_sb.sb_logsunit;
929 		} else if (mp->m_logbsize > 0 &&
930 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
931 			xfs_warn(mp,
932 		"logbuf size must be greater than or equal to log stripe size");
933 			return -EINVAL;
934 		}
935 	} else {
936 		/* Fail a mount if the logbuf is larger than 32K */
937 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
938 			xfs_warn(mp,
939 		"logbuf size for version 1 logs must be 16K or 32K");
940 			return -EINVAL;
941 		}
942 	}
943 
944 	/*
945 	 * V5 filesystems always use attr2 format for attributes.
946 	 */
947 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
948 	    (mp->m_flags & XFS_MOUNT_NOATTR2)) {
949 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
950 			     "attr2 is always enabled for V5 filesystems.");
951 		return -EINVAL;
952 	}
953 
954 	/*
955 	 * mkfs'ed attr2 will turn on attr2 mount unless explicitly
956 	 * told by noattr2 to turn it off
957 	 */
958 	if (xfs_sb_version_hasattr2(&mp->m_sb) &&
959 	    !(mp->m_flags & XFS_MOUNT_NOATTR2))
960 		mp->m_flags |= XFS_MOUNT_ATTR2;
961 
962 	/*
963 	 * prohibit r/w mounts of read-only filesystems
964 	 */
965 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !ronly) {
966 		xfs_warn(mp,
967 			"cannot mount a read-only filesystem as read-write");
968 		return -EROFS;
969 	}
970 
971 	if ((mp->m_qflags & (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE)) &&
972 	    (mp->m_qflags & (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE)) &&
973 	    !xfs_sb_version_has_pquotino(&mp->m_sb)) {
974 		xfs_warn(mp,
975 		  "Super block does not support project and group quota together");
976 		return -EINVAL;
977 	}
978 
979 	return 0;
980 }
981 
982 static int
983 xfs_init_percpu_counters(
984 	struct xfs_mount	*mp)
985 {
986 	int		error;
987 
988 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
989 	if (error)
990 		return -ENOMEM;
991 
992 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
993 	if (error)
994 		goto free_icount;
995 
996 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
997 	if (error)
998 		goto free_ifree;
999 
1000 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
1001 	if (error)
1002 		goto free_fdblocks;
1003 
1004 	return 0;
1005 
1006 free_fdblocks:
1007 	percpu_counter_destroy(&mp->m_fdblocks);
1008 free_ifree:
1009 	percpu_counter_destroy(&mp->m_ifree);
1010 free_icount:
1011 	percpu_counter_destroy(&mp->m_icount);
1012 	return -ENOMEM;
1013 }
1014 
1015 void
1016 xfs_reinit_percpu_counters(
1017 	struct xfs_mount	*mp)
1018 {
1019 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1020 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1021 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1022 }
1023 
1024 static void
1025 xfs_destroy_percpu_counters(
1026 	struct xfs_mount	*mp)
1027 {
1028 	percpu_counter_destroy(&mp->m_icount);
1029 	percpu_counter_destroy(&mp->m_ifree);
1030 	percpu_counter_destroy(&mp->m_fdblocks);
1031 	ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
1032 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1033 	percpu_counter_destroy(&mp->m_delalloc_blks);
1034 }
1035 
1036 static void
1037 xfs_fs_put_super(
1038 	struct super_block	*sb)
1039 {
1040 	struct xfs_mount	*mp = XFS_M(sb);
1041 
1042 	/* if ->fill_super failed, we have no mount to tear down */
1043 	if (!sb->s_fs_info)
1044 		return;
1045 
1046 	xfs_notice(mp, "Unmounting Filesystem");
1047 	xfs_filestream_unmount(mp);
1048 	xfs_unmountfs(mp);
1049 
1050 	xfs_freesb(mp);
1051 	free_percpu(mp->m_stats.xs_stats);
1052 	xfs_destroy_percpu_counters(mp);
1053 	xfs_destroy_mount_workqueues(mp);
1054 	xfs_close_devices(mp);
1055 
1056 	sb->s_fs_info = NULL;
1057 	xfs_mount_free(mp);
1058 }
1059 
1060 static long
1061 xfs_fs_nr_cached_objects(
1062 	struct super_block	*sb,
1063 	struct shrink_control	*sc)
1064 {
1065 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1066 	if (WARN_ON_ONCE(!sb->s_fs_info))
1067 		return 0;
1068 	return xfs_reclaim_inodes_count(XFS_M(sb));
1069 }
1070 
1071 static long
1072 xfs_fs_free_cached_objects(
1073 	struct super_block	*sb,
1074 	struct shrink_control	*sc)
1075 {
1076 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1077 }
1078 
1079 static const struct super_operations xfs_super_operations = {
1080 	.alloc_inode		= xfs_fs_alloc_inode,
1081 	.destroy_inode		= xfs_fs_destroy_inode,
1082 	.dirty_inode		= xfs_fs_dirty_inode,
1083 	.drop_inode		= xfs_fs_drop_inode,
1084 	.put_super		= xfs_fs_put_super,
1085 	.sync_fs		= xfs_fs_sync_fs,
1086 	.freeze_fs		= xfs_fs_freeze,
1087 	.unfreeze_fs		= xfs_fs_unfreeze,
1088 	.statfs			= xfs_fs_statfs,
1089 	.show_options		= xfs_fs_show_options,
1090 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1091 	.free_cached_objects	= xfs_fs_free_cached_objects,
1092 };
1093 
1094 static int
1095 suffix_kstrtoint(
1096 	const char	*s,
1097 	unsigned int	base,
1098 	int		*res)
1099 {
1100 	int		last, shift_left_factor = 0, _res;
1101 	char		*value;
1102 	int		ret = 0;
1103 
1104 	value = kstrdup(s, GFP_KERNEL);
1105 	if (!value)
1106 		return -ENOMEM;
1107 
1108 	last = strlen(value) - 1;
1109 	if (value[last] == 'K' || value[last] == 'k') {
1110 		shift_left_factor = 10;
1111 		value[last] = '\0';
1112 	}
1113 	if (value[last] == 'M' || value[last] == 'm') {
1114 		shift_left_factor = 20;
1115 		value[last] = '\0';
1116 	}
1117 	if (value[last] == 'G' || value[last] == 'g') {
1118 		shift_left_factor = 30;
1119 		value[last] = '\0';
1120 	}
1121 
1122 	if (kstrtoint(value, base, &_res))
1123 		ret = -EINVAL;
1124 	kfree(value);
1125 	*res = _res << shift_left_factor;
1126 	return ret;
1127 }
1128 
1129 static inline void
1130 xfs_fs_warn_deprecated(
1131 	struct fs_context	*fc,
1132 	struct fs_parameter	*param,
1133 	uint64_t		flag,
1134 	bool			value)
1135 {
1136 	/* Don't print the warning if reconfiguring and current mount point
1137 	 * already had the flag set
1138 	 */
1139 	if ((fc->purpose & FS_CONTEXT_FOR_RECONFIGURE) &&
1140 			!!(XFS_M(fc->root->d_sb)->m_flags & flag) == value)
1141 		return;
1142 	xfs_warn(fc->s_fs_info, "%s mount option is deprecated.", param->key);
1143 }
1144 
1145 /*
1146  * Set mount state from a mount option.
1147  *
1148  * NOTE: mp->m_super is NULL here!
1149  */
1150 static int
1151 xfs_fs_parse_param(
1152 	struct fs_context	*fc,
1153 	struct fs_parameter	*param)
1154 {
1155 	struct xfs_mount	*parsing_mp = fc->s_fs_info;
1156 	struct fs_parse_result	result;
1157 	int			size = 0;
1158 	int			opt;
1159 
1160 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1161 	if (opt < 0)
1162 		return opt;
1163 
1164 	switch (opt) {
1165 	case Opt_logbufs:
1166 		parsing_mp->m_logbufs = result.uint_32;
1167 		return 0;
1168 	case Opt_logbsize:
1169 		if (suffix_kstrtoint(param->string, 10, &parsing_mp->m_logbsize))
1170 			return -EINVAL;
1171 		return 0;
1172 	case Opt_logdev:
1173 		kfree(parsing_mp->m_logname);
1174 		parsing_mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1175 		if (!parsing_mp->m_logname)
1176 			return -ENOMEM;
1177 		return 0;
1178 	case Opt_rtdev:
1179 		kfree(parsing_mp->m_rtname);
1180 		parsing_mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1181 		if (!parsing_mp->m_rtname)
1182 			return -ENOMEM;
1183 		return 0;
1184 	case Opt_allocsize:
1185 		if (suffix_kstrtoint(param->string, 10, &size))
1186 			return -EINVAL;
1187 		parsing_mp->m_allocsize_log = ffs(size) - 1;
1188 		parsing_mp->m_flags |= XFS_MOUNT_ALLOCSIZE;
1189 		return 0;
1190 	case Opt_grpid:
1191 	case Opt_bsdgroups:
1192 		parsing_mp->m_flags |= XFS_MOUNT_GRPID;
1193 		return 0;
1194 	case Opt_nogrpid:
1195 	case Opt_sysvgroups:
1196 		parsing_mp->m_flags &= ~XFS_MOUNT_GRPID;
1197 		return 0;
1198 	case Opt_wsync:
1199 		parsing_mp->m_flags |= XFS_MOUNT_WSYNC;
1200 		return 0;
1201 	case Opt_norecovery:
1202 		parsing_mp->m_flags |= XFS_MOUNT_NORECOVERY;
1203 		return 0;
1204 	case Opt_noalign:
1205 		parsing_mp->m_flags |= XFS_MOUNT_NOALIGN;
1206 		return 0;
1207 	case Opt_swalloc:
1208 		parsing_mp->m_flags |= XFS_MOUNT_SWALLOC;
1209 		return 0;
1210 	case Opt_sunit:
1211 		parsing_mp->m_dalign = result.uint_32;
1212 		return 0;
1213 	case Opt_swidth:
1214 		parsing_mp->m_swidth = result.uint_32;
1215 		return 0;
1216 	case Opt_inode32:
1217 		parsing_mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1218 		return 0;
1219 	case Opt_inode64:
1220 		parsing_mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1221 		return 0;
1222 	case Opt_nouuid:
1223 		parsing_mp->m_flags |= XFS_MOUNT_NOUUID;
1224 		return 0;
1225 	case Opt_largeio:
1226 		parsing_mp->m_flags |= XFS_MOUNT_LARGEIO;
1227 		return 0;
1228 	case Opt_nolargeio:
1229 		parsing_mp->m_flags &= ~XFS_MOUNT_LARGEIO;
1230 		return 0;
1231 	case Opt_filestreams:
1232 		parsing_mp->m_flags |= XFS_MOUNT_FILESTREAMS;
1233 		return 0;
1234 	case Opt_noquota:
1235 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1236 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1237 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACTIVE;
1238 		return 0;
1239 	case Opt_quota:
1240 	case Opt_uquota:
1241 	case Opt_usrquota:
1242 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE |
1243 				 XFS_UQUOTA_ENFD);
1244 		return 0;
1245 	case Opt_qnoenforce:
1246 	case Opt_uqnoenforce:
1247 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE);
1248 		parsing_mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1249 		return 0;
1250 	case Opt_pquota:
1251 	case Opt_prjquota:
1252 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE |
1253 				 XFS_PQUOTA_ENFD);
1254 		return 0;
1255 	case Opt_pqnoenforce:
1256 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE);
1257 		parsing_mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1258 		return 0;
1259 	case Opt_gquota:
1260 	case Opt_grpquota:
1261 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE |
1262 				 XFS_GQUOTA_ENFD);
1263 		return 0;
1264 	case Opt_gqnoenforce:
1265 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE);
1266 		parsing_mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1267 		return 0;
1268 	case Opt_discard:
1269 		parsing_mp->m_flags |= XFS_MOUNT_DISCARD;
1270 		return 0;
1271 	case Opt_nodiscard:
1272 		parsing_mp->m_flags &= ~XFS_MOUNT_DISCARD;
1273 		return 0;
1274 #ifdef CONFIG_FS_DAX
1275 	case Opt_dax:
1276 		xfs_mount_set_dax_mode(parsing_mp, XFS_DAX_ALWAYS);
1277 		return 0;
1278 	case Opt_dax_enum:
1279 		xfs_mount_set_dax_mode(parsing_mp, result.uint_32);
1280 		return 0;
1281 #endif
1282 	/* Following mount options will be removed in September 2025 */
1283 	case Opt_ikeep:
1284 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_IKEEP, true);
1285 		parsing_mp->m_flags |= XFS_MOUNT_IKEEP;
1286 		return 0;
1287 	case Opt_noikeep:
1288 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_IKEEP, false);
1289 		parsing_mp->m_flags &= ~XFS_MOUNT_IKEEP;
1290 		return 0;
1291 	case Opt_attr2:
1292 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_ATTR2, true);
1293 		parsing_mp->m_flags |= XFS_MOUNT_ATTR2;
1294 		return 0;
1295 	case Opt_noattr2:
1296 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_NOATTR2, true);
1297 		parsing_mp->m_flags &= ~XFS_MOUNT_ATTR2;
1298 		parsing_mp->m_flags |= XFS_MOUNT_NOATTR2;
1299 		return 0;
1300 	default:
1301 		xfs_warn(parsing_mp, "unknown mount option [%s].", param->key);
1302 		return -EINVAL;
1303 	}
1304 
1305 	return 0;
1306 }
1307 
1308 static int
1309 xfs_fs_validate_params(
1310 	struct xfs_mount	*mp)
1311 {
1312 	/*
1313 	 * no recovery flag requires a read-only mount
1314 	 */
1315 	if ((mp->m_flags & XFS_MOUNT_NORECOVERY) &&
1316 	    !(mp->m_flags & XFS_MOUNT_RDONLY)) {
1317 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1318 		return -EINVAL;
1319 	}
1320 
1321 	if ((mp->m_flags & XFS_MOUNT_NOALIGN) &&
1322 	    (mp->m_dalign || mp->m_swidth)) {
1323 		xfs_warn(mp,
1324 	"sunit and swidth options incompatible with the noalign option");
1325 		return -EINVAL;
1326 	}
1327 
1328 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1329 		xfs_warn(mp, "quota support not available in this kernel.");
1330 		return -EINVAL;
1331 	}
1332 
1333 	if ((mp->m_dalign && !mp->m_swidth) ||
1334 	    (!mp->m_dalign && mp->m_swidth)) {
1335 		xfs_warn(mp, "sunit and swidth must be specified together");
1336 		return -EINVAL;
1337 	}
1338 
1339 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1340 		xfs_warn(mp,
1341 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1342 			mp->m_swidth, mp->m_dalign);
1343 		return -EINVAL;
1344 	}
1345 
1346 	if (mp->m_logbufs != -1 &&
1347 	    mp->m_logbufs != 0 &&
1348 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1349 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1350 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1351 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1352 		return -EINVAL;
1353 	}
1354 
1355 	if (mp->m_logbsize != -1 &&
1356 	    mp->m_logbsize !=  0 &&
1357 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1358 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1359 	     !is_power_of_2(mp->m_logbsize))) {
1360 		xfs_warn(mp,
1361 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1362 			mp->m_logbsize);
1363 		return -EINVAL;
1364 	}
1365 
1366 	if ((mp->m_flags & XFS_MOUNT_ALLOCSIZE) &&
1367 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1368 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1369 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1370 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1371 		return -EINVAL;
1372 	}
1373 
1374 	return 0;
1375 }
1376 
1377 static int
1378 xfs_fs_fill_super(
1379 	struct super_block	*sb,
1380 	struct fs_context	*fc)
1381 {
1382 	struct xfs_mount	*mp = sb->s_fs_info;
1383 	struct inode		*root;
1384 	int			flags = 0, error;
1385 
1386 	mp->m_super = sb;
1387 
1388 	error = xfs_fs_validate_params(mp);
1389 	if (error)
1390 		goto out_free_names;
1391 
1392 	sb_min_blocksize(sb, BBSIZE);
1393 	sb->s_xattr = xfs_xattr_handlers;
1394 	sb->s_export_op = &xfs_export_operations;
1395 #ifdef CONFIG_XFS_QUOTA
1396 	sb->s_qcop = &xfs_quotactl_operations;
1397 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1398 #endif
1399 	sb->s_op = &xfs_super_operations;
1400 
1401 	/*
1402 	 * Delay mount work if the debug hook is set. This is debug
1403 	 * instrumention to coordinate simulation of xfs mount failures with
1404 	 * VFS superblock operations
1405 	 */
1406 	if (xfs_globals.mount_delay) {
1407 		xfs_notice(mp, "Delaying mount for %d seconds.",
1408 			xfs_globals.mount_delay);
1409 		msleep(xfs_globals.mount_delay * 1000);
1410 	}
1411 
1412 	if (fc->sb_flags & SB_SILENT)
1413 		flags |= XFS_MFSI_QUIET;
1414 
1415 	error = xfs_open_devices(mp);
1416 	if (error)
1417 		goto out_free_names;
1418 
1419 	error = xfs_init_mount_workqueues(mp);
1420 	if (error)
1421 		goto out_close_devices;
1422 
1423 	error = xfs_init_percpu_counters(mp);
1424 	if (error)
1425 		goto out_destroy_workqueues;
1426 
1427 	/* Allocate stats memory before we do operations that might use it */
1428 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1429 	if (!mp->m_stats.xs_stats) {
1430 		error = -ENOMEM;
1431 		goto out_destroy_counters;
1432 	}
1433 
1434 	error = xfs_readsb(mp, flags);
1435 	if (error)
1436 		goto out_free_stats;
1437 
1438 	error = xfs_finish_flags(mp);
1439 	if (error)
1440 		goto out_free_sb;
1441 
1442 	error = xfs_setup_devices(mp);
1443 	if (error)
1444 		goto out_free_sb;
1445 
1446 	/* V4 support is undergoing deprecation. */
1447 	if (!xfs_sb_version_hascrc(&mp->m_sb)) {
1448 #ifdef CONFIG_XFS_SUPPORT_V4
1449 		xfs_warn_once(mp,
1450 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1451 #else
1452 		xfs_warn(mp,
1453 	"Deprecated V4 format (crc=0) not supported by kernel.");
1454 		error = -EINVAL;
1455 		goto out_free_sb;
1456 #endif
1457 	}
1458 
1459 	/* Filesystem claims it needs repair, so refuse the mount. */
1460 	if (xfs_sb_version_needsrepair(&mp->m_sb)) {
1461 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1462 		error = -EFSCORRUPTED;
1463 		goto out_free_sb;
1464 	}
1465 
1466 	/*
1467 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1468 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1469 	 * we don't check them at all.
1470 	 */
1471 	if (mp->m_sb.sb_inprogress) {
1472 		xfs_warn(mp, "Offline file system operation in progress!");
1473 		error = -EFSCORRUPTED;
1474 		goto out_free_sb;
1475 	}
1476 
1477 	/*
1478 	 * Until this is fixed only page-sized or smaller data blocks work.
1479 	 */
1480 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1481 		xfs_warn(mp,
1482 		"File system with blocksize %d bytes. "
1483 		"Only pagesize (%ld) or less will currently work.",
1484 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1485 		error = -ENOSYS;
1486 		goto out_free_sb;
1487 	}
1488 
1489 	/* Ensure this filesystem fits in the page cache limits */
1490 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1491 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1492 		xfs_warn(mp,
1493 		"file system too large to be mounted on this system.");
1494 		error = -EFBIG;
1495 		goto out_free_sb;
1496 	}
1497 
1498 	/*
1499 	 * XFS block mappings use 54 bits to store the logical block offset.
1500 	 * This should suffice to handle the maximum file size that the VFS
1501 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1502 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1503 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1504 	 * to check this assertion.
1505 	 *
1506 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1507 	 * maximum pagecache offset in units of fs blocks.
1508 	 */
1509 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1510 		xfs_warn(mp,
1511 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1512 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1513 			 XFS_MAX_FILEOFF);
1514 		error = -EINVAL;
1515 		goto out_free_sb;
1516 	}
1517 
1518 	error = xfs_filestream_mount(mp);
1519 	if (error)
1520 		goto out_free_sb;
1521 
1522 	/*
1523 	 * we must configure the block size in the superblock before we run the
1524 	 * full mount process as the mount process can lookup and cache inodes.
1525 	 */
1526 	sb->s_magic = XFS_SUPER_MAGIC;
1527 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1528 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1529 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1530 	sb->s_max_links = XFS_MAXLINK;
1531 	sb->s_time_gran = 1;
1532 	if (xfs_sb_version_hasbigtime(&mp->m_sb)) {
1533 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1534 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1535 	} else {
1536 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1537 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1538 	}
1539 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1540 	sb->s_iflags |= SB_I_CGROUPWB;
1541 
1542 	set_posix_acl_flag(sb);
1543 
1544 	/* version 5 superblocks support inode version counters. */
1545 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1546 		sb->s_flags |= SB_I_VERSION;
1547 
1548 	if (xfs_sb_version_hasbigtime(&mp->m_sb))
1549 		xfs_warn(mp,
1550  "EXPERIMENTAL big timestamp feature in use. Use at your own risk!");
1551 
1552 	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS) {
1553 		bool rtdev_is_dax = false, datadev_is_dax;
1554 
1555 		xfs_warn(mp,
1556 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1557 
1558 		datadev_is_dax = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
1559 			sb->s_blocksize);
1560 		if (mp->m_rtdev_targp)
1561 			rtdev_is_dax = bdev_dax_supported(
1562 				mp->m_rtdev_targp->bt_bdev, sb->s_blocksize);
1563 		if (!rtdev_is_dax && !datadev_is_dax) {
1564 			xfs_alert(mp,
1565 			"DAX unsupported by block device. Turning off DAX.");
1566 			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
1567 		}
1568 		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1569 			xfs_alert(mp,
1570 		"DAX and reflink cannot be used together!");
1571 			error = -EINVAL;
1572 			goto out_filestream_unmount;
1573 		}
1574 	}
1575 
1576 	if (mp->m_flags & XFS_MOUNT_DISCARD) {
1577 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1578 
1579 		if (!blk_queue_discard(q)) {
1580 			xfs_warn(mp, "mounting with \"discard\" option, but "
1581 					"the device does not support discard");
1582 			mp->m_flags &= ~XFS_MOUNT_DISCARD;
1583 		}
1584 	}
1585 
1586 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1587 		if (mp->m_sb.sb_rblocks) {
1588 			xfs_alert(mp,
1589 	"reflink not compatible with realtime device!");
1590 			error = -EINVAL;
1591 			goto out_filestream_unmount;
1592 		}
1593 
1594 		if (xfs_globals.always_cow) {
1595 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1596 			mp->m_always_cow = true;
1597 		}
1598 	}
1599 
1600 	if (xfs_sb_version_hasrmapbt(&mp->m_sb) && mp->m_sb.sb_rblocks) {
1601 		xfs_alert(mp,
1602 	"reverse mapping btree not compatible with realtime device!");
1603 		error = -EINVAL;
1604 		goto out_filestream_unmount;
1605 	}
1606 
1607 	if (xfs_sb_version_hasinobtcounts(&mp->m_sb))
1608 		xfs_warn(mp,
1609  "EXPERIMENTAL inode btree counters feature in use. Use at your own risk!");
1610 
1611 	error = xfs_mountfs(mp);
1612 	if (error)
1613 		goto out_filestream_unmount;
1614 
1615 	root = igrab(VFS_I(mp->m_rootip));
1616 	if (!root) {
1617 		error = -ENOENT;
1618 		goto out_unmount;
1619 	}
1620 	sb->s_root = d_make_root(root);
1621 	if (!sb->s_root) {
1622 		error = -ENOMEM;
1623 		goto out_unmount;
1624 	}
1625 
1626 	return 0;
1627 
1628  out_filestream_unmount:
1629 	xfs_filestream_unmount(mp);
1630  out_free_sb:
1631 	xfs_freesb(mp);
1632  out_free_stats:
1633 	free_percpu(mp->m_stats.xs_stats);
1634  out_destroy_counters:
1635 	xfs_destroy_percpu_counters(mp);
1636  out_destroy_workqueues:
1637 	xfs_destroy_mount_workqueues(mp);
1638  out_close_devices:
1639 	xfs_close_devices(mp);
1640  out_free_names:
1641 	sb->s_fs_info = NULL;
1642 	xfs_mount_free(mp);
1643 	return error;
1644 
1645  out_unmount:
1646 	xfs_filestream_unmount(mp);
1647 	xfs_unmountfs(mp);
1648 	goto out_free_sb;
1649 }
1650 
1651 static int
1652 xfs_fs_get_tree(
1653 	struct fs_context	*fc)
1654 {
1655 	return get_tree_bdev(fc, xfs_fs_fill_super);
1656 }
1657 
1658 static int
1659 xfs_remount_rw(
1660 	struct xfs_mount	*mp)
1661 {
1662 	struct xfs_sb		*sbp = &mp->m_sb;
1663 	int error;
1664 
1665 	if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
1666 		xfs_warn(mp,
1667 			"ro->rw transition prohibited on norecovery mount");
1668 		return -EINVAL;
1669 	}
1670 
1671 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
1672 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1673 		xfs_warn(mp,
1674 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1675 			(sbp->sb_features_ro_compat &
1676 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1677 		return -EINVAL;
1678 	}
1679 
1680 	mp->m_flags &= ~XFS_MOUNT_RDONLY;
1681 
1682 	/*
1683 	 * If this is the first remount to writeable state we might have some
1684 	 * superblock changes to update.
1685 	 */
1686 	if (mp->m_update_sb) {
1687 		error = xfs_sync_sb(mp, false);
1688 		if (error) {
1689 			xfs_warn(mp, "failed to write sb changes");
1690 			return error;
1691 		}
1692 		mp->m_update_sb = false;
1693 	}
1694 
1695 	/*
1696 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1697 	 * it is non-zero, otherwise go with the default.
1698 	 */
1699 	xfs_restore_resvblks(mp);
1700 	xfs_log_work_queue(mp);
1701 
1702 	/* Recover any CoW blocks that never got remapped. */
1703 	error = xfs_reflink_recover_cow(mp);
1704 	if (error) {
1705 		xfs_err(mp,
1706 			"Error %d recovering leftover CoW allocations.", error);
1707 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1708 		return error;
1709 	}
1710 	xfs_blockgc_start(mp);
1711 
1712 	/* Create the per-AG metadata reservation pool .*/
1713 	error = xfs_fs_reserve_ag_blocks(mp);
1714 	if (error && error != -ENOSPC)
1715 		return error;
1716 
1717 	return 0;
1718 }
1719 
1720 static int
1721 xfs_remount_ro(
1722 	struct xfs_mount	*mp)
1723 {
1724 	int error;
1725 
1726 	/*
1727 	 * Cancel background eofb scanning so it cannot race with the final
1728 	 * log force+buftarg wait and deadlock the remount.
1729 	 */
1730 	xfs_blockgc_stop(mp);
1731 
1732 	/* Get rid of any leftover CoW reservations... */
1733 	error = xfs_blockgc_free_space(mp, NULL);
1734 	if (error) {
1735 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1736 		return error;
1737 	}
1738 
1739 	/* Free the per-AG metadata reservation pool. */
1740 	error = xfs_fs_unreserve_ag_blocks(mp);
1741 	if (error) {
1742 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1743 		return error;
1744 	}
1745 
1746 	/*
1747 	 * Before we sync the metadata, we need to free up the reserve block
1748 	 * pool so that the used block count in the superblock on disk is
1749 	 * correct at the end of the remount. Stash the current* reserve pool
1750 	 * size so that if we get remounted rw, we can return it to the same
1751 	 * size.
1752 	 */
1753 	xfs_save_resvblks(mp);
1754 
1755 	xfs_log_clean(mp);
1756 	mp->m_flags |= XFS_MOUNT_RDONLY;
1757 
1758 	return 0;
1759 }
1760 
1761 /*
1762  * Logically we would return an error here to prevent users from believing
1763  * they might have changed mount options using remount which can't be changed.
1764  *
1765  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1766  * arguments in some cases so we can't blindly reject options, but have to
1767  * check for each specified option if it actually differs from the currently
1768  * set option and only reject it if that's the case.
1769  *
1770  * Until that is implemented we return success for every remount request, and
1771  * silently ignore all options that we can't actually change.
1772  */
1773 static int
1774 xfs_fs_reconfigure(
1775 	struct fs_context *fc)
1776 {
1777 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1778 	struct xfs_mount        *new_mp = fc->s_fs_info;
1779 	xfs_sb_t		*sbp = &mp->m_sb;
1780 	int			flags = fc->sb_flags;
1781 	int			error;
1782 
1783 	/* version 5 superblocks always support version counters. */
1784 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1785 		fc->sb_flags |= SB_I_VERSION;
1786 
1787 	error = xfs_fs_validate_params(new_mp);
1788 	if (error)
1789 		return error;
1790 
1791 	sync_filesystem(mp->m_super);
1792 
1793 	/* inode32 -> inode64 */
1794 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1795 	    !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1796 		mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1797 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1798 	}
1799 
1800 	/* inode64 -> inode32 */
1801 	if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1802 	    (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1803 		mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1804 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1805 	}
1806 
1807 	/* ro -> rw */
1808 	if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) {
1809 		error = xfs_remount_rw(mp);
1810 		if (error)
1811 			return error;
1812 	}
1813 
1814 	/* rw -> ro */
1815 	if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) {
1816 		error = xfs_remount_ro(mp);
1817 		if (error)
1818 			return error;
1819 	}
1820 
1821 	return 0;
1822 }
1823 
1824 static void xfs_fs_free(
1825 	struct fs_context	*fc)
1826 {
1827 	struct xfs_mount	*mp = fc->s_fs_info;
1828 
1829 	/*
1830 	 * mp is stored in the fs_context when it is initialized.
1831 	 * mp is transferred to the superblock on a successful mount,
1832 	 * but if an error occurs before the transfer we have to free
1833 	 * it here.
1834 	 */
1835 	if (mp)
1836 		xfs_mount_free(mp);
1837 }
1838 
1839 static const struct fs_context_operations xfs_context_ops = {
1840 	.parse_param = xfs_fs_parse_param,
1841 	.get_tree    = xfs_fs_get_tree,
1842 	.reconfigure = xfs_fs_reconfigure,
1843 	.free        = xfs_fs_free,
1844 };
1845 
1846 static int xfs_init_fs_context(
1847 	struct fs_context	*fc)
1848 {
1849 	struct xfs_mount	*mp;
1850 
1851 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1852 	if (!mp)
1853 		return -ENOMEM;
1854 
1855 	spin_lock_init(&mp->m_sb_lock);
1856 	spin_lock_init(&mp->m_agirotor_lock);
1857 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1858 	spin_lock_init(&mp->m_perag_lock);
1859 	mutex_init(&mp->m_growlock);
1860 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1861 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1862 	mp->m_kobj.kobject.kset = xfs_kset;
1863 	/*
1864 	 * We don't create the finobt per-ag space reservation until after log
1865 	 * recovery, so we must set this to true so that an ifree transaction
1866 	 * started during log recovery will not depend on space reservations
1867 	 * for finobt expansion.
1868 	 */
1869 	mp->m_finobt_nores = true;
1870 
1871 	/*
1872 	 * These can be overridden by the mount option parsing.
1873 	 */
1874 	mp->m_logbufs = -1;
1875 	mp->m_logbsize = -1;
1876 	mp->m_allocsize_log = 16; /* 64k */
1877 
1878 	/*
1879 	 * Copy binary VFS mount flags we are interested in.
1880 	 */
1881 	if (fc->sb_flags & SB_RDONLY)
1882 		mp->m_flags |= XFS_MOUNT_RDONLY;
1883 	if (fc->sb_flags & SB_DIRSYNC)
1884 		mp->m_flags |= XFS_MOUNT_DIRSYNC;
1885 	if (fc->sb_flags & SB_SYNCHRONOUS)
1886 		mp->m_flags |= XFS_MOUNT_WSYNC;
1887 
1888 	fc->s_fs_info = mp;
1889 	fc->ops = &xfs_context_ops;
1890 
1891 	return 0;
1892 }
1893 
1894 static struct file_system_type xfs_fs_type = {
1895 	.owner			= THIS_MODULE,
1896 	.name			= "xfs",
1897 	.init_fs_context	= xfs_init_fs_context,
1898 	.parameters		= xfs_fs_parameters,
1899 	.kill_sb		= kill_block_super,
1900 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1901 };
1902 MODULE_ALIAS_FS("xfs");
1903 
1904 STATIC int __init
1905 xfs_init_zones(void)
1906 {
1907 	xfs_log_ticket_zone = kmem_cache_create("xfs_log_ticket",
1908 						sizeof(struct xlog_ticket),
1909 						0, 0, NULL);
1910 	if (!xfs_log_ticket_zone)
1911 		goto out;
1912 
1913 	xfs_bmap_free_item_zone = kmem_cache_create("xfs_bmap_free_item",
1914 					sizeof(struct xfs_extent_free_item),
1915 					0, 0, NULL);
1916 	if (!xfs_bmap_free_item_zone)
1917 		goto out_destroy_log_ticket_zone;
1918 
1919 	xfs_btree_cur_zone = kmem_cache_create("xfs_btree_cur",
1920 					       sizeof(struct xfs_btree_cur),
1921 					       0, 0, NULL);
1922 	if (!xfs_btree_cur_zone)
1923 		goto out_destroy_bmap_free_item_zone;
1924 
1925 	xfs_da_state_zone = kmem_cache_create("xfs_da_state",
1926 					      sizeof(struct xfs_da_state),
1927 					      0, 0, NULL);
1928 	if (!xfs_da_state_zone)
1929 		goto out_destroy_btree_cur_zone;
1930 
1931 	xfs_ifork_zone = kmem_cache_create("xfs_ifork",
1932 					   sizeof(struct xfs_ifork),
1933 					   0, 0, NULL);
1934 	if (!xfs_ifork_zone)
1935 		goto out_destroy_da_state_zone;
1936 
1937 	xfs_trans_zone = kmem_cache_create("xfs_trans",
1938 					   sizeof(struct xfs_trans),
1939 					   0, 0, NULL);
1940 	if (!xfs_trans_zone)
1941 		goto out_destroy_ifork_zone;
1942 
1943 
1944 	/*
1945 	 * The size of the zone allocated buf log item is the maximum
1946 	 * size possible under XFS.  This wastes a little bit of memory,
1947 	 * but it is much faster.
1948 	 */
1949 	xfs_buf_item_zone = kmem_cache_create("xfs_buf_item",
1950 					      sizeof(struct xfs_buf_log_item),
1951 					      0, 0, NULL);
1952 	if (!xfs_buf_item_zone)
1953 		goto out_destroy_trans_zone;
1954 
1955 	xfs_efd_zone = kmem_cache_create("xfs_efd_item",
1956 					(sizeof(struct xfs_efd_log_item) +
1957 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
1958 					sizeof(struct xfs_extent)),
1959 					0, 0, NULL);
1960 	if (!xfs_efd_zone)
1961 		goto out_destroy_buf_item_zone;
1962 
1963 	xfs_efi_zone = kmem_cache_create("xfs_efi_item",
1964 					 (sizeof(struct xfs_efi_log_item) +
1965 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
1966 					 sizeof(struct xfs_extent)),
1967 					 0, 0, NULL);
1968 	if (!xfs_efi_zone)
1969 		goto out_destroy_efd_zone;
1970 
1971 	xfs_inode_zone = kmem_cache_create("xfs_inode",
1972 					   sizeof(struct xfs_inode), 0,
1973 					   (SLAB_HWCACHE_ALIGN |
1974 					    SLAB_RECLAIM_ACCOUNT |
1975 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
1976 					   xfs_fs_inode_init_once);
1977 	if (!xfs_inode_zone)
1978 		goto out_destroy_efi_zone;
1979 
1980 	xfs_ili_zone = kmem_cache_create("xfs_ili",
1981 					 sizeof(struct xfs_inode_log_item), 0,
1982 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
1983 					 NULL);
1984 	if (!xfs_ili_zone)
1985 		goto out_destroy_inode_zone;
1986 
1987 	xfs_icreate_zone = kmem_cache_create("xfs_icr",
1988 					     sizeof(struct xfs_icreate_item),
1989 					     0, 0, NULL);
1990 	if (!xfs_icreate_zone)
1991 		goto out_destroy_ili_zone;
1992 
1993 	xfs_rud_zone = kmem_cache_create("xfs_rud_item",
1994 					 sizeof(struct xfs_rud_log_item),
1995 					 0, 0, NULL);
1996 	if (!xfs_rud_zone)
1997 		goto out_destroy_icreate_zone;
1998 
1999 	xfs_rui_zone = kmem_cache_create("xfs_rui_item",
2000 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
2001 			0, 0, NULL);
2002 	if (!xfs_rui_zone)
2003 		goto out_destroy_rud_zone;
2004 
2005 	xfs_cud_zone = kmem_cache_create("xfs_cud_item",
2006 					 sizeof(struct xfs_cud_log_item),
2007 					 0, 0, NULL);
2008 	if (!xfs_cud_zone)
2009 		goto out_destroy_rui_zone;
2010 
2011 	xfs_cui_zone = kmem_cache_create("xfs_cui_item",
2012 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2013 			0, 0, NULL);
2014 	if (!xfs_cui_zone)
2015 		goto out_destroy_cud_zone;
2016 
2017 	xfs_bud_zone = kmem_cache_create("xfs_bud_item",
2018 					 sizeof(struct xfs_bud_log_item),
2019 					 0, 0, NULL);
2020 	if (!xfs_bud_zone)
2021 		goto out_destroy_cui_zone;
2022 
2023 	xfs_bui_zone = kmem_cache_create("xfs_bui_item",
2024 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2025 			0, 0, NULL);
2026 	if (!xfs_bui_zone)
2027 		goto out_destroy_bud_zone;
2028 
2029 	return 0;
2030 
2031  out_destroy_bud_zone:
2032 	kmem_cache_destroy(xfs_bud_zone);
2033  out_destroy_cui_zone:
2034 	kmem_cache_destroy(xfs_cui_zone);
2035  out_destroy_cud_zone:
2036 	kmem_cache_destroy(xfs_cud_zone);
2037  out_destroy_rui_zone:
2038 	kmem_cache_destroy(xfs_rui_zone);
2039  out_destroy_rud_zone:
2040 	kmem_cache_destroy(xfs_rud_zone);
2041  out_destroy_icreate_zone:
2042 	kmem_cache_destroy(xfs_icreate_zone);
2043  out_destroy_ili_zone:
2044 	kmem_cache_destroy(xfs_ili_zone);
2045  out_destroy_inode_zone:
2046 	kmem_cache_destroy(xfs_inode_zone);
2047  out_destroy_efi_zone:
2048 	kmem_cache_destroy(xfs_efi_zone);
2049  out_destroy_efd_zone:
2050 	kmem_cache_destroy(xfs_efd_zone);
2051  out_destroy_buf_item_zone:
2052 	kmem_cache_destroy(xfs_buf_item_zone);
2053  out_destroy_trans_zone:
2054 	kmem_cache_destroy(xfs_trans_zone);
2055  out_destroy_ifork_zone:
2056 	kmem_cache_destroy(xfs_ifork_zone);
2057  out_destroy_da_state_zone:
2058 	kmem_cache_destroy(xfs_da_state_zone);
2059  out_destroy_btree_cur_zone:
2060 	kmem_cache_destroy(xfs_btree_cur_zone);
2061  out_destroy_bmap_free_item_zone:
2062 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2063  out_destroy_log_ticket_zone:
2064 	kmem_cache_destroy(xfs_log_ticket_zone);
2065  out:
2066 	return -ENOMEM;
2067 }
2068 
2069 STATIC void
2070 xfs_destroy_zones(void)
2071 {
2072 	/*
2073 	 * Make sure all delayed rcu free are flushed before we
2074 	 * destroy caches.
2075 	 */
2076 	rcu_barrier();
2077 	kmem_cache_destroy(xfs_bui_zone);
2078 	kmem_cache_destroy(xfs_bud_zone);
2079 	kmem_cache_destroy(xfs_cui_zone);
2080 	kmem_cache_destroy(xfs_cud_zone);
2081 	kmem_cache_destroy(xfs_rui_zone);
2082 	kmem_cache_destroy(xfs_rud_zone);
2083 	kmem_cache_destroy(xfs_icreate_zone);
2084 	kmem_cache_destroy(xfs_ili_zone);
2085 	kmem_cache_destroy(xfs_inode_zone);
2086 	kmem_cache_destroy(xfs_efi_zone);
2087 	kmem_cache_destroy(xfs_efd_zone);
2088 	kmem_cache_destroy(xfs_buf_item_zone);
2089 	kmem_cache_destroy(xfs_trans_zone);
2090 	kmem_cache_destroy(xfs_ifork_zone);
2091 	kmem_cache_destroy(xfs_da_state_zone);
2092 	kmem_cache_destroy(xfs_btree_cur_zone);
2093 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2094 	kmem_cache_destroy(xfs_log_ticket_zone);
2095 }
2096 
2097 STATIC int __init
2098 xfs_init_workqueues(void)
2099 {
2100 	/*
2101 	 * The allocation workqueue can be used in memory reclaim situations
2102 	 * (writepage path), and parallelism is only limited by the number of
2103 	 * AGs in all the filesystems mounted. Hence use the default large
2104 	 * max_active value for this workqueue.
2105 	 */
2106 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2107 			XFS_WQFLAGS(WQ_MEM_RECLAIM | WQ_FREEZABLE), 0);
2108 	if (!xfs_alloc_wq)
2109 		return -ENOMEM;
2110 
2111 	xfs_discard_wq = alloc_workqueue("xfsdiscard", XFS_WQFLAGS(WQ_UNBOUND),
2112 			0);
2113 	if (!xfs_discard_wq)
2114 		goto out_free_alloc_wq;
2115 
2116 	return 0;
2117 out_free_alloc_wq:
2118 	destroy_workqueue(xfs_alloc_wq);
2119 	return -ENOMEM;
2120 }
2121 
2122 STATIC void
2123 xfs_destroy_workqueues(void)
2124 {
2125 	destroy_workqueue(xfs_discard_wq);
2126 	destroy_workqueue(xfs_alloc_wq);
2127 }
2128 
2129 STATIC int __init
2130 init_xfs_fs(void)
2131 {
2132 	int			error;
2133 
2134 	xfs_check_ondisk_structs();
2135 
2136 	printk(KERN_INFO XFS_VERSION_STRING " with "
2137 			 XFS_BUILD_OPTIONS " enabled\n");
2138 
2139 	xfs_dir_startup();
2140 
2141 	error = xfs_init_zones();
2142 	if (error)
2143 		goto out;
2144 
2145 	error = xfs_init_workqueues();
2146 	if (error)
2147 		goto out_destroy_zones;
2148 
2149 	error = xfs_mru_cache_init();
2150 	if (error)
2151 		goto out_destroy_wq;
2152 
2153 	error = xfs_buf_init();
2154 	if (error)
2155 		goto out_mru_cache_uninit;
2156 
2157 	error = xfs_init_procfs();
2158 	if (error)
2159 		goto out_buf_terminate;
2160 
2161 	error = xfs_sysctl_register();
2162 	if (error)
2163 		goto out_cleanup_procfs;
2164 
2165 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2166 	if (!xfs_kset) {
2167 		error = -ENOMEM;
2168 		goto out_sysctl_unregister;
2169 	}
2170 
2171 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2172 
2173 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2174 	if (!xfsstats.xs_stats) {
2175 		error = -ENOMEM;
2176 		goto out_kset_unregister;
2177 	}
2178 
2179 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2180 			       "stats");
2181 	if (error)
2182 		goto out_free_stats;
2183 
2184 #ifdef DEBUG
2185 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2186 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2187 	if (error)
2188 		goto out_remove_stats_kobj;
2189 #endif
2190 
2191 	error = xfs_qm_init();
2192 	if (error)
2193 		goto out_remove_dbg_kobj;
2194 
2195 	error = register_filesystem(&xfs_fs_type);
2196 	if (error)
2197 		goto out_qm_exit;
2198 	return 0;
2199 
2200  out_qm_exit:
2201 	xfs_qm_exit();
2202  out_remove_dbg_kobj:
2203 #ifdef DEBUG
2204 	xfs_sysfs_del(&xfs_dbg_kobj);
2205  out_remove_stats_kobj:
2206 #endif
2207 	xfs_sysfs_del(&xfsstats.xs_kobj);
2208  out_free_stats:
2209 	free_percpu(xfsstats.xs_stats);
2210  out_kset_unregister:
2211 	kset_unregister(xfs_kset);
2212  out_sysctl_unregister:
2213 	xfs_sysctl_unregister();
2214  out_cleanup_procfs:
2215 	xfs_cleanup_procfs();
2216  out_buf_terminate:
2217 	xfs_buf_terminate();
2218  out_mru_cache_uninit:
2219 	xfs_mru_cache_uninit();
2220  out_destroy_wq:
2221 	xfs_destroy_workqueues();
2222  out_destroy_zones:
2223 	xfs_destroy_zones();
2224  out:
2225 	return error;
2226 }
2227 
2228 STATIC void __exit
2229 exit_xfs_fs(void)
2230 {
2231 	xfs_qm_exit();
2232 	unregister_filesystem(&xfs_fs_type);
2233 #ifdef DEBUG
2234 	xfs_sysfs_del(&xfs_dbg_kobj);
2235 #endif
2236 	xfs_sysfs_del(&xfsstats.xs_kobj);
2237 	free_percpu(xfsstats.xs_stats);
2238 	kset_unregister(xfs_kset);
2239 	xfs_sysctl_unregister();
2240 	xfs_cleanup_procfs();
2241 	xfs_buf_terminate();
2242 	xfs_mru_cache_uninit();
2243 	xfs_destroy_workqueues();
2244 	xfs_destroy_zones();
2245 	xfs_uuid_table_free();
2246 }
2247 
2248 module_init(init_xfs_fs);
2249 module_exit(exit_xfs_fs);
2250 
2251 MODULE_AUTHOR("Silicon Graphics, Inc.");
2252 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2253 MODULE_LICENSE("GPL");
2254