xref: /openbmc/linux/fs/xfs/xfs_super.c (revision 5fb859f7)
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 #include "xfs_ag.h"
40 #include "xfs_defer.h"
41 #include "xfs_attr_item.h"
42 #include "xfs_xattr.h"
43 
44 #include <linux/magic.h>
45 #include <linux/fs_context.h>
46 #include <linux/fs_parser.h>
47 
48 static const struct super_operations xfs_super_operations;
49 
50 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
51 #ifdef DEBUG
52 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
53 #endif
54 
55 #ifdef CONFIG_HOTPLUG_CPU
56 static LIST_HEAD(xfs_mount_list);
57 static DEFINE_SPINLOCK(xfs_mount_list_lock);
58 
59 static inline void xfs_mount_list_add(struct xfs_mount *mp)
60 {
61 	spin_lock(&xfs_mount_list_lock);
62 	list_add(&mp->m_mount_list, &xfs_mount_list);
63 	spin_unlock(&xfs_mount_list_lock);
64 }
65 
66 static inline void xfs_mount_list_del(struct xfs_mount *mp)
67 {
68 	spin_lock(&xfs_mount_list_lock);
69 	list_del(&mp->m_mount_list);
70 	spin_unlock(&xfs_mount_list_lock);
71 }
72 #else /* !CONFIG_HOTPLUG_CPU */
73 static inline void xfs_mount_list_add(struct xfs_mount *mp) {}
74 static inline void xfs_mount_list_del(struct xfs_mount *mp) {}
75 #endif
76 
77 enum xfs_dax_mode {
78 	XFS_DAX_INODE = 0,
79 	XFS_DAX_ALWAYS = 1,
80 	XFS_DAX_NEVER = 2,
81 };
82 
83 static void
84 xfs_mount_set_dax_mode(
85 	struct xfs_mount	*mp,
86 	enum xfs_dax_mode	mode)
87 {
88 	switch (mode) {
89 	case XFS_DAX_INODE:
90 		mp->m_features &= ~(XFS_FEAT_DAX_ALWAYS | XFS_FEAT_DAX_NEVER);
91 		break;
92 	case XFS_DAX_ALWAYS:
93 		mp->m_features |= XFS_FEAT_DAX_ALWAYS;
94 		mp->m_features &= ~XFS_FEAT_DAX_NEVER;
95 		break;
96 	case XFS_DAX_NEVER:
97 		mp->m_features |= XFS_FEAT_DAX_NEVER;
98 		mp->m_features &= ~XFS_FEAT_DAX_ALWAYS;
99 		break;
100 	}
101 }
102 
103 static const struct constant_table dax_param_enums[] = {
104 	{"inode",	XFS_DAX_INODE },
105 	{"always",	XFS_DAX_ALWAYS },
106 	{"never",	XFS_DAX_NEVER },
107 	{}
108 };
109 
110 /*
111  * Table driven mount option parser.
112  */
113 enum {
114 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
115 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
116 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
117 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
118 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
119 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
120 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
121 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
122 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
123 };
124 
125 static const struct fs_parameter_spec xfs_fs_parameters[] = {
126 	fsparam_u32("logbufs",		Opt_logbufs),
127 	fsparam_string("logbsize",	Opt_logbsize),
128 	fsparam_string("logdev",	Opt_logdev),
129 	fsparam_string("rtdev",		Opt_rtdev),
130 	fsparam_flag("wsync",		Opt_wsync),
131 	fsparam_flag("noalign",		Opt_noalign),
132 	fsparam_flag("swalloc",		Opt_swalloc),
133 	fsparam_u32("sunit",		Opt_sunit),
134 	fsparam_u32("swidth",		Opt_swidth),
135 	fsparam_flag("nouuid",		Opt_nouuid),
136 	fsparam_flag("grpid",		Opt_grpid),
137 	fsparam_flag("nogrpid",		Opt_nogrpid),
138 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
139 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
140 	fsparam_string("allocsize",	Opt_allocsize),
141 	fsparam_flag("norecovery",	Opt_norecovery),
142 	fsparam_flag("inode64",		Opt_inode64),
143 	fsparam_flag("inode32",		Opt_inode32),
144 	fsparam_flag("ikeep",		Opt_ikeep),
145 	fsparam_flag("noikeep",		Opt_noikeep),
146 	fsparam_flag("largeio",		Opt_largeio),
147 	fsparam_flag("nolargeio",	Opt_nolargeio),
148 	fsparam_flag("attr2",		Opt_attr2),
149 	fsparam_flag("noattr2",		Opt_noattr2),
150 	fsparam_flag("filestreams",	Opt_filestreams),
151 	fsparam_flag("quota",		Opt_quota),
152 	fsparam_flag("noquota",		Opt_noquota),
153 	fsparam_flag("usrquota",	Opt_usrquota),
154 	fsparam_flag("grpquota",	Opt_grpquota),
155 	fsparam_flag("prjquota",	Opt_prjquota),
156 	fsparam_flag("uquota",		Opt_uquota),
157 	fsparam_flag("gquota",		Opt_gquota),
158 	fsparam_flag("pquota",		Opt_pquota),
159 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
160 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
161 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
162 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
163 	fsparam_flag("discard",		Opt_discard),
164 	fsparam_flag("nodiscard",	Opt_nodiscard),
165 	fsparam_flag("dax",		Opt_dax),
166 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
167 	{}
168 };
169 
170 struct proc_xfs_info {
171 	uint64_t	flag;
172 	char		*str;
173 };
174 
175 static int
176 xfs_fs_show_options(
177 	struct seq_file		*m,
178 	struct dentry		*root)
179 {
180 	static struct proc_xfs_info xfs_info_set[] = {
181 		/* the few simple ones we can get from the mount struct */
182 		{ XFS_FEAT_IKEEP,		",ikeep" },
183 		{ XFS_FEAT_WSYNC,		",wsync" },
184 		{ XFS_FEAT_NOALIGN,		",noalign" },
185 		{ XFS_FEAT_SWALLOC,		",swalloc" },
186 		{ XFS_FEAT_NOUUID,		",nouuid" },
187 		{ XFS_FEAT_NORECOVERY,		",norecovery" },
188 		{ XFS_FEAT_ATTR2,		",attr2" },
189 		{ XFS_FEAT_FILESTREAMS,		",filestreams" },
190 		{ XFS_FEAT_GRPID,		",grpid" },
191 		{ XFS_FEAT_DISCARD,		",discard" },
192 		{ XFS_FEAT_LARGE_IOSIZE,	",largeio" },
193 		{ XFS_FEAT_DAX_ALWAYS,		",dax=always" },
194 		{ XFS_FEAT_DAX_NEVER,		",dax=never" },
195 		{ 0, NULL }
196 	};
197 	struct xfs_mount	*mp = XFS_M(root->d_sb);
198 	struct proc_xfs_info	*xfs_infop;
199 
200 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
201 		if (mp->m_features & xfs_infop->flag)
202 			seq_puts(m, xfs_infop->str);
203 	}
204 
205 	seq_printf(m, ",inode%d", xfs_has_small_inums(mp) ? 32 : 64);
206 
207 	if (xfs_has_allocsize(mp))
208 		seq_printf(m, ",allocsize=%dk",
209 			   (1 << mp->m_allocsize_log) >> 10);
210 
211 	if (mp->m_logbufs > 0)
212 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
213 	if (mp->m_logbsize > 0)
214 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
215 
216 	if (mp->m_logname)
217 		seq_show_option(m, "logdev", mp->m_logname);
218 	if (mp->m_rtname)
219 		seq_show_option(m, "rtdev", mp->m_rtname);
220 
221 	if (mp->m_dalign > 0)
222 		seq_printf(m, ",sunit=%d",
223 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
224 	if (mp->m_swidth > 0)
225 		seq_printf(m, ",swidth=%d",
226 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
227 
228 	if (mp->m_qflags & XFS_UQUOTA_ENFD)
229 		seq_puts(m, ",usrquota");
230 	else if (mp->m_qflags & XFS_UQUOTA_ACCT)
231 		seq_puts(m, ",uqnoenforce");
232 
233 	if (mp->m_qflags & XFS_PQUOTA_ENFD)
234 		seq_puts(m, ",prjquota");
235 	else if (mp->m_qflags & XFS_PQUOTA_ACCT)
236 		seq_puts(m, ",pqnoenforce");
237 
238 	if (mp->m_qflags & XFS_GQUOTA_ENFD)
239 		seq_puts(m, ",grpquota");
240 	else if (mp->m_qflags & XFS_GQUOTA_ACCT)
241 		seq_puts(m, ",gqnoenforce");
242 
243 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
244 		seq_puts(m, ",noquota");
245 
246 	return 0;
247 }
248 
249 /*
250  * Set parameters for inode allocation heuristics, taking into account
251  * filesystem size and inode32/inode64 mount options; i.e. specifically
252  * whether or not XFS_FEAT_SMALL_INUMS is set.
253  *
254  * Inode allocation patterns are altered only if inode32 is requested
255  * (XFS_FEAT_SMALL_INUMS), and the filesystem is sufficiently large.
256  * If altered, XFS_OPSTATE_INODE32 is set as well.
257  *
258  * An agcount independent of that in the mount structure is provided
259  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
260  * to the potentially higher ag count.
261  *
262  * Returns the maximum AG index which may contain inodes.
263  */
264 xfs_agnumber_t
265 xfs_set_inode_alloc(
266 	struct xfs_mount *mp,
267 	xfs_agnumber_t	agcount)
268 {
269 	xfs_agnumber_t	index;
270 	xfs_agnumber_t	maxagi = 0;
271 	xfs_sb_t	*sbp = &mp->m_sb;
272 	xfs_agnumber_t	max_metadata;
273 	xfs_agino_t	agino;
274 	xfs_ino_t	ino;
275 
276 	/*
277 	 * Calculate how much should be reserved for inodes to meet
278 	 * the max inode percentage.  Used only for inode32.
279 	 */
280 	if (M_IGEO(mp)->maxicount) {
281 		uint64_t	icount;
282 
283 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
284 		do_div(icount, 100);
285 		icount += sbp->sb_agblocks - 1;
286 		do_div(icount, sbp->sb_agblocks);
287 		max_metadata = icount;
288 	} else {
289 		max_metadata = agcount;
290 	}
291 
292 	/* Get the last possible inode in the filesystem */
293 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
294 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
295 
296 	/*
297 	 * If user asked for no more than 32-bit inodes, and the fs is
298 	 * sufficiently large, set XFS_OPSTATE_INODE32 if we must alter
299 	 * the allocator to accommodate the request.
300 	 */
301 	if (xfs_has_small_inums(mp) && ino > XFS_MAXINUMBER_32)
302 		set_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
303 	else
304 		clear_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
305 
306 	for (index = 0; index < agcount; index++) {
307 		struct xfs_perag	*pag;
308 
309 		ino = XFS_AGINO_TO_INO(mp, index, agino);
310 
311 		pag = xfs_perag_get(mp, index);
312 
313 		if (xfs_is_inode32(mp)) {
314 			if (ino > XFS_MAXINUMBER_32) {
315 				pag->pagi_inodeok = 0;
316 				pag->pagf_metadata = 0;
317 			} else {
318 				pag->pagi_inodeok = 1;
319 				maxagi++;
320 				if (index < max_metadata)
321 					pag->pagf_metadata = 1;
322 				else
323 					pag->pagf_metadata = 0;
324 			}
325 		} else {
326 			pag->pagi_inodeok = 1;
327 			pag->pagf_metadata = 0;
328 		}
329 
330 		xfs_perag_put(pag);
331 	}
332 
333 	return xfs_is_inode32(mp) ? maxagi : agcount;
334 }
335 
336 static int
337 xfs_setup_dax_always(
338 	struct xfs_mount	*mp)
339 {
340 	if (!mp->m_ddev_targp->bt_daxdev &&
341 	    (!mp->m_rtdev_targp || !mp->m_rtdev_targp->bt_daxdev)) {
342 		xfs_alert(mp,
343 			"DAX unsupported by block device. Turning off DAX.");
344 		goto disable_dax;
345 	}
346 
347 	if (mp->m_super->s_blocksize != PAGE_SIZE) {
348 		xfs_alert(mp,
349 			"DAX not supported for blocksize. Turning off DAX.");
350 		goto disable_dax;
351 	}
352 
353 	if (xfs_has_reflink(mp)) {
354 		xfs_alert(mp, "DAX and reflink cannot be used together!");
355 		return -EINVAL;
356 	}
357 
358 	xfs_warn(mp, "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
359 	return 0;
360 
361 disable_dax:
362 	xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
363 	return 0;
364 }
365 
366 STATIC int
367 xfs_blkdev_get(
368 	xfs_mount_t		*mp,
369 	const char		*name,
370 	struct block_device	**bdevp)
371 {
372 	int			error = 0;
373 
374 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
375 				    mp);
376 	if (IS_ERR(*bdevp)) {
377 		error = PTR_ERR(*bdevp);
378 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
379 	}
380 
381 	return error;
382 }
383 
384 STATIC void
385 xfs_blkdev_put(
386 	struct block_device	*bdev)
387 {
388 	if (bdev)
389 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
390 }
391 
392 STATIC void
393 xfs_close_devices(
394 	struct xfs_mount	*mp)
395 {
396 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
397 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
398 
399 		xfs_free_buftarg(mp->m_logdev_targp);
400 		xfs_blkdev_put(logdev);
401 	}
402 	if (mp->m_rtdev_targp) {
403 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
404 
405 		xfs_free_buftarg(mp->m_rtdev_targp);
406 		xfs_blkdev_put(rtdev);
407 	}
408 	xfs_free_buftarg(mp->m_ddev_targp);
409 }
410 
411 /*
412  * The file system configurations are:
413  *	(1) device (partition) with data and internal log
414  *	(2) logical volume with data and log subvolumes.
415  *	(3) logical volume with data, log, and realtime subvolumes.
416  *
417  * We only have to handle opening the log and realtime volumes here if
418  * they are present.  The data subvolume has already been opened by
419  * get_sb_bdev() and is stored in sb->s_bdev.
420  */
421 STATIC int
422 xfs_open_devices(
423 	struct xfs_mount	*mp)
424 {
425 	struct block_device	*ddev = mp->m_super->s_bdev;
426 	struct block_device	*logdev = NULL, *rtdev = NULL;
427 	int			error;
428 
429 	/*
430 	 * Open real time and log devices - order is important.
431 	 */
432 	if (mp->m_logname) {
433 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
434 		if (error)
435 			return error;
436 	}
437 
438 	if (mp->m_rtname) {
439 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
440 		if (error)
441 			goto out_close_logdev;
442 
443 		if (rtdev == ddev || rtdev == logdev) {
444 			xfs_warn(mp,
445 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
446 			error = -EINVAL;
447 			goto out_close_rtdev;
448 		}
449 	}
450 
451 	/*
452 	 * Setup xfs_mount buffer target pointers
453 	 */
454 	error = -ENOMEM;
455 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev);
456 	if (!mp->m_ddev_targp)
457 		goto out_close_rtdev;
458 
459 	if (rtdev) {
460 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev);
461 		if (!mp->m_rtdev_targp)
462 			goto out_free_ddev_targ;
463 	}
464 
465 	if (logdev && logdev != ddev) {
466 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev);
467 		if (!mp->m_logdev_targp)
468 			goto out_free_rtdev_targ;
469 	} else {
470 		mp->m_logdev_targp = mp->m_ddev_targp;
471 	}
472 
473 	return 0;
474 
475  out_free_rtdev_targ:
476 	if (mp->m_rtdev_targp)
477 		xfs_free_buftarg(mp->m_rtdev_targp);
478  out_free_ddev_targ:
479 	xfs_free_buftarg(mp->m_ddev_targp);
480  out_close_rtdev:
481 	xfs_blkdev_put(rtdev);
482  out_close_logdev:
483 	if (logdev && logdev != ddev)
484 		xfs_blkdev_put(logdev);
485 	return error;
486 }
487 
488 /*
489  * Setup xfs_mount buffer target pointers based on superblock
490  */
491 STATIC int
492 xfs_setup_devices(
493 	struct xfs_mount	*mp)
494 {
495 	int			error;
496 
497 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
498 	if (error)
499 		return error;
500 
501 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
502 		unsigned int	log_sector_size = BBSIZE;
503 
504 		if (xfs_has_sector(mp))
505 			log_sector_size = mp->m_sb.sb_logsectsize;
506 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
507 					    log_sector_size);
508 		if (error)
509 			return error;
510 	}
511 	if (mp->m_rtdev_targp) {
512 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
513 					    mp->m_sb.sb_sectsize);
514 		if (error)
515 			return error;
516 	}
517 
518 	return 0;
519 }
520 
521 STATIC int
522 xfs_init_mount_workqueues(
523 	struct xfs_mount	*mp)
524 {
525 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
526 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
527 			1, mp->m_super->s_id);
528 	if (!mp->m_buf_workqueue)
529 		goto out;
530 
531 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
532 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
533 			0, mp->m_super->s_id);
534 	if (!mp->m_unwritten_workqueue)
535 		goto out_destroy_buf;
536 
537 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
538 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
539 			0, mp->m_super->s_id);
540 	if (!mp->m_reclaim_workqueue)
541 		goto out_destroy_unwritten;
542 
543 	mp->m_blockgc_wq = alloc_workqueue("xfs-blockgc/%s",
544 			XFS_WQFLAGS(WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM),
545 			0, mp->m_super->s_id);
546 	if (!mp->m_blockgc_wq)
547 		goto out_destroy_reclaim;
548 
549 	mp->m_inodegc_wq = alloc_workqueue("xfs-inodegc/%s",
550 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
551 			1, mp->m_super->s_id);
552 	if (!mp->m_inodegc_wq)
553 		goto out_destroy_blockgc;
554 
555 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
556 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
557 	if (!mp->m_sync_workqueue)
558 		goto out_destroy_inodegc;
559 
560 	return 0;
561 
562 out_destroy_inodegc:
563 	destroy_workqueue(mp->m_inodegc_wq);
564 out_destroy_blockgc:
565 	destroy_workqueue(mp->m_blockgc_wq);
566 out_destroy_reclaim:
567 	destroy_workqueue(mp->m_reclaim_workqueue);
568 out_destroy_unwritten:
569 	destroy_workqueue(mp->m_unwritten_workqueue);
570 out_destroy_buf:
571 	destroy_workqueue(mp->m_buf_workqueue);
572 out:
573 	return -ENOMEM;
574 }
575 
576 STATIC void
577 xfs_destroy_mount_workqueues(
578 	struct xfs_mount	*mp)
579 {
580 	destroy_workqueue(mp->m_sync_workqueue);
581 	destroy_workqueue(mp->m_blockgc_wq);
582 	destroy_workqueue(mp->m_inodegc_wq);
583 	destroy_workqueue(mp->m_reclaim_workqueue);
584 	destroy_workqueue(mp->m_unwritten_workqueue);
585 	destroy_workqueue(mp->m_buf_workqueue);
586 }
587 
588 static void
589 xfs_flush_inodes_worker(
590 	struct work_struct	*work)
591 {
592 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
593 						   m_flush_inodes_work);
594 	struct super_block	*sb = mp->m_super;
595 
596 	if (down_read_trylock(&sb->s_umount)) {
597 		sync_inodes_sb(sb);
598 		up_read(&sb->s_umount);
599 	}
600 }
601 
602 /*
603  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
604  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
605  * for IO to complete so that we effectively throttle multiple callers to the
606  * rate at which IO is completing.
607  */
608 void
609 xfs_flush_inodes(
610 	struct xfs_mount	*mp)
611 {
612 	/*
613 	 * If flush_work() returns true then that means we waited for a flush
614 	 * which was already in progress.  Don't bother running another scan.
615 	 */
616 	if (flush_work(&mp->m_flush_inodes_work))
617 		return;
618 
619 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
620 	flush_work(&mp->m_flush_inodes_work);
621 }
622 
623 /* Catch misguided souls that try to use this interface on XFS */
624 STATIC struct inode *
625 xfs_fs_alloc_inode(
626 	struct super_block	*sb)
627 {
628 	BUG();
629 	return NULL;
630 }
631 
632 /*
633  * Now that the generic code is guaranteed not to be accessing
634  * the linux inode, we can inactivate and reclaim the inode.
635  */
636 STATIC void
637 xfs_fs_destroy_inode(
638 	struct inode		*inode)
639 {
640 	struct xfs_inode	*ip = XFS_I(inode);
641 
642 	trace_xfs_destroy_inode(ip);
643 
644 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
645 	XFS_STATS_INC(ip->i_mount, vn_rele);
646 	XFS_STATS_INC(ip->i_mount, vn_remove);
647 	xfs_inode_mark_reclaimable(ip);
648 }
649 
650 static void
651 xfs_fs_dirty_inode(
652 	struct inode			*inode,
653 	int				flag)
654 {
655 	struct xfs_inode		*ip = XFS_I(inode);
656 	struct xfs_mount		*mp = ip->i_mount;
657 	struct xfs_trans		*tp;
658 
659 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
660 		return;
661 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
662 		return;
663 
664 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
665 		return;
666 	xfs_ilock(ip, XFS_ILOCK_EXCL);
667 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
668 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
669 	xfs_trans_commit(tp);
670 }
671 
672 /*
673  * Slab object creation initialisation for the XFS inode.
674  * This covers only the idempotent fields in the XFS inode;
675  * all other fields need to be initialised on allocation
676  * from the slab. This avoids the need to repeatedly initialise
677  * fields in the xfs inode that left in the initialise state
678  * when freeing the inode.
679  */
680 STATIC void
681 xfs_fs_inode_init_once(
682 	void			*inode)
683 {
684 	struct xfs_inode	*ip = inode;
685 
686 	memset(ip, 0, sizeof(struct xfs_inode));
687 
688 	/* vfs inode */
689 	inode_init_once(VFS_I(ip));
690 
691 	/* xfs inode */
692 	atomic_set(&ip->i_pincount, 0);
693 	spin_lock_init(&ip->i_flags_lock);
694 
695 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
696 		     "xfsino", ip->i_ino);
697 }
698 
699 /*
700  * We do an unlocked check for XFS_IDONTCACHE here because we are already
701  * serialised against cache hits here via the inode->i_lock and igrab() in
702  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
703  * racing with us, and it avoids needing to grab a spinlock here for every inode
704  * we drop the final reference on.
705  */
706 STATIC int
707 xfs_fs_drop_inode(
708 	struct inode		*inode)
709 {
710 	struct xfs_inode	*ip = XFS_I(inode);
711 
712 	/*
713 	 * If this unlinked inode is in the middle of recovery, don't
714 	 * drop the inode just yet; log recovery will take care of
715 	 * that.  See the comment for this inode flag.
716 	 */
717 	if (ip->i_flags & XFS_IRECOVERY) {
718 		ASSERT(xlog_recovery_needed(ip->i_mount->m_log));
719 		return 0;
720 	}
721 
722 	return generic_drop_inode(inode);
723 }
724 
725 static void
726 xfs_mount_free(
727 	struct xfs_mount	*mp)
728 {
729 	kfree(mp->m_rtname);
730 	kfree(mp->m_logname);
731 	kmem_free(mp);
732 }
733 
734 STATIC int
735 xfs_fs_sync_fs(
736 	struct super_block	*sb,
737 	int			wait)
738 {
739 	struct xfs_mount	*mp = XFS_M(sb);
740 	int			error;
741 
742 	trace_xfs_fs_sync_fs(mp, __return_address);
743 
744 	/*
745 	 * Doing anything during the async pass would be counterproductive.
746 	 */
747 	if (!wait)
748 		return 0;
749 
750 	error = xfs_log_force(mp, XFS_LOG_SYNC);
751 	if (error)
752 		return error;
753 
754 	if (laptop_mode) {
755 		/*
756 		 * The disk must be active because we're syncing.
757 		 * We schedule log work now (now that the disk is
758 		 * active) instead of later (when it might not be).
759 		 */
760 		flush_delayed_work(&mp->m_log->l_work);
761 	}
762 
763 	/*
764 	 * If we are called with page faults frozen out, it means we are about
765 	 * to freeze the transaction subsystem. Take the opportunity to shut
766 	 * down inodegc because once SB_FREEZE_FS is set it's too late to
767 	 * prevent inactivation races with freeze. The fs doesn't get called
768 	 * again by the freezing process until after SB_FREEZE_FS has been set,
769 	 * so it's now or never.  Same logic applies to speculative allocation
770 	 * garbage collection.
771 	 *
772 	 * We don't care if this is a normal syncfs call that does this or
773 	 * freeze that does this - we can run this multiple times without issue
774 	 * and we won't race with a restart because a restart can only occur
775 	 * when the state is either SB_FREEZE_FS or SB_FREEZE_COMPLETE.
776 	 */
777 	if (sb->s_writers.frozen == SB_FREEZE_PAGEFAULT) {
778 		xfs_inodegc_stop(mp);
779 		xfs_blockgc_stop(mp);
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 	/*
801 	 * Expedite background inodegc but don't wait. We do not want to block
802 	 * here waiting hours for a billion extent file to be truncated.
803 	 */
804 	xfs_inodegc_push(mp);
805 
806 	statp->f_type = XFS_SUPER_MAGIC;
807 	statp->f_namelen = MAXNAMELEN - 1;
808 
809 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
810 	statp->f_fsid = u64_to_fsid(id);
811 
812 	icount = percpu_counter_sum(&mp->m_icount);
813 	ifree = percpu_counter_sum(&mp->m_ifree);
814 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
815 
816 	spin_lock(&mp->m_sb_lock);
817 	statp->f_bsize = sbp->sb_blocksize;
818 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
819 	statp->f_blocks = sbp->sb_dblocks - lsize;
820 	spin_unlock(&mp->m_sb_lock);
821 
822 	/* make sure statp->f_bfree does not underflow */
823 	statp->f_bfree = max_t(int64_t, 0,
824 				fdblocks - xfs_fdblocks_unavailable(mp));
825 	statp->f_bavail = statp->f_bfree;
826 
827 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
828 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
829 	if (M_IGEO(mp)->maxicount)
830 		statp->f_files = min_t(typeof(statp->f_files),
831 					statp->f_files,
832 					M_IGEO(mp)->maxicount);
833 
834 	/* If sb_icount overshot maxicount, report actual allocation */
835 	statp->f_files = max_t(typeof(statp->f_files),
836 					statp->f_files,
837 					sbp->sb_icount);
838 
839 	/* make sure statp->f_ffree does not underflow */
840 	ffree = statp->f_files - (icount - ifree);
841 	statp->f_ffree = max_t(int64_t, ffree, 0);
842 
843 
844 	if ((ip->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
845 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
846 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
847 		xfs_qm_statvfs(ip, statp);
848 
849 	if (XFS_IS_REALTIME_MOUNT(mp) &&
850 	    (ip->i_diflags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
851 		s64	freertx;
852 
853 		statp->f_blocks = sbp->sb_rblocks;
854 		freertx = percpu_counter_sum_positive(&mp->m_frextents);
855 		statp->f_bavail = statp->f_bfree = freertx * sbp->sb_rextsize;
856 	}
857 
858 	return 0;
859 }
860 
861 STATIC void
862 xfs_save_resvblks(struct xfs_mount *mp)
863 {
864 	uint64_t resblks = 0;
865 
866 	mp->m_resblks_save = mp->m_resblks;
867 	xfs_reserve_blocks(mp, &resblks, NULL);
868 }
869 
870 STATIC void
871 xfs_restore_resvblks(struct xfs_mount *mp)
872 {
873 	uint64_t resblks;
874 
875 	if (mp->m_resblks_save) {
876 		resblks = mp->m_resblks_save;
877 		mp->m_resblks_save = 0;
878 	} else
879 		resblks = xfs_default_resblks(mp);
880 
881 	xfs_reserve_blocks(mp, &resblks, NULL);
882 }
883 
884 /*
885  * Second stage of a freeze. The data is already frozen so we only
886  * need to take care of the metadata. Once that's done sync the superblock
887  * to the log to dirty it in case of a crash while frozen. This ensures that we
888  * will recover the unlinked inode lists on the next mount.
889  */
890 STATIC int
891 xfs_fs_freeze(
892 	struct super_block	*sb)
893 {
894 	struct xfs_mount	*mp = XFS_M(sb);
895 	unsigned int		flags;
896 	int			ret;
897 
898 	/*
899 	 * The filesystem is now frozen far enough that memory reclaim
900 	 * cannot safely operate on the filesystem. Hence we need to
901 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
902 	 */
903 	flags = memalloc_nofs_save();
904 	xfs_save_resvblks(mp);
905 	ret = xfs_log_quiesce(mp);
906 	memalloc_nofs_restore(flags);
907 
908 	/*
909 	 * For read-write filesystems, we need to restart the inodegc on error
910 	 * because we stopped it at SB_FREEZE_PAGEFAULT level and a thaw is not
911 	 * going to be run to restart it now.  We are at SB_FREEZE_FS level
912 	 * here, so we can restart safely without racing with a stop in
913 	 * xfs_fs_sync_fs().
914 	 */
915 	if (ret && !xfs_is_readonly(mp)) {
916 		xfs_blockgc_start(mp);
917 		xfs_inodegc_start(mp);
918 	}
919 
920 	return ret;
921 }
922 
923 STATIC int
924 xfs_fs_unfreeze(
925 	struct super_block	*sb)
926 {
927 	struct xfs_mount	*mp = XFS_M(sb);
928 
929 	xfs_restore_resvblks(mp);
930 	xfs_log_work_queue(mp);
931 
932 	/*
933 	 * Don't reactivate the inodegc worker on a readonly filesystem because
934 	 * inodes are sent directly to reclaim.  Don't reactivate the blockgc
935 	 * worker because there are no speculative preallocations on a readonly
936 	 * filesystem.
937 	 */
938 	if (!xfs_is_readonly(mp)) {
939 		xfs_blockgc_start(mp);
940 		xfs_inodegc_start(mp);
941 	}
942 
943 	return 0;
944 }
945 
946 /*
947  * This function fills in xfs_mount_t fields based on mount args.
948  * Note: the superblock _has_ now been read in.
949  */
950 STATIC int
951 xfs_finish_flags(
952 	struct xfs_mount	*mp)
953 {
954 	/* Fail a mount where the logbuf is smaller than the log stripe */
955 	if (xfs_has_logv2(mp)) {
956 		if (mp->m_logbsize <= 0 &&
957 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
958 			mp->m_logbsize = mp->m_sb.sb_logsunit;
959 		} else if (mp->m_logbsize > 0 &&
960 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
961 			xfs_warn(mp,
962 		"logbuf size must be greater than or equal to log stripe size");
963 			return -EINVAL;
964 		}
965 	} else {
966 		/* Fail a mount if the logbuf is larger than 32K */
967 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
968 			xfs_warn(mp,
969 		"logbuf size for version 1 logs must be 16K or 32K");
970 			return -EINVAL;
971 		}
972 	}
973 
974 	/*
975 	 * V5 filesystems always use attr2 format for attributes.
976 	 */
977 	if (xfs_has_crc(mp) && xfs_has_noattr2(mp)) {
978 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
979 			     "attr2 is always enabled for V5 filesystems.");
980 		return -EINVAL;
981 	}
982 
983 	/*
984 	 * prohibit r/w mounts of read-only filesystems
985 	 */
986 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !xfs_is_readonly(mp)) {
987 		xfs_warn(mp,
988 			"cannot mount a read-only filesystem as read-write");
989 		return -EROFS;
990 	}
991 
992 	if ((mp->m_qflags & XFS_GQUOTA_ACCT) &&
993 	    (mp->m_qflags & XFS_PQUOTA_ACCT) &&
994 	    !xfs_has_pquotino(mp)) {
995 		xfs_warn(mp,
996 		  "Super block does not support project and group quota together");
997 		return -EINVAL;
998 	}
999 
1000 	return 0;
1001 }
1002 
1003 static int
1004 xfs_init_percpu_counters(
1005 	struct xfs_mount	*mp)
1006 {
1007 	int		error;
1008 
1009 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
1010 	if (error)
1011 		return -ENOMEM;
1012 
1013 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
1014 	if (error)
1015 		goto free_icount;
1016 
1017 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
1018 	if (error)
1019 		goto free_ifree;
1020 
1021 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
1022 	if (error)
1023 		goto free_fdblocks;
1024 
1025 	error = percpu_counter_init(&mp->m_frextents, 0, GFP_KERNEL);
1026 	if (error)
1027 		goto free_delalloc;
1028 
1029 	return 0;
1030 
1031 free_delalloc:
1032 	percpu_counter_destroy(&mp->m_delalloc_blks);
1033 free_fdblocks:
1034 	percpu_counter_destroy(&mp->m_fdblocks);
1035 free_ifree:
1036 	percpu_counter_destroy(&mp->m_ifree);
1037 free_icount:
1038 	percpu_counter_destroy(&mp->m_icount);
1039 	return -ENOMEM;
1040 }
1041 
1042 void
1043 xfs_reinit_percpu_counters(
1044 	struct xfs_mount	*mp)
1045 {
1046 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1047 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1048 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1049 	percpu_counter_set(&mp->m_frextents, mp->m_sb.sb_frextents);
1050 }
1051 
1052 static void
1053 xfs_destroy_percpu_counters(
1054 	struct xfs_mount	*mp)
1055 {
1056 	percpu_counter_destroy(&mp->m_icount);
1057 	percpu_counter_destroy(&mp->m_ifree);
1058 	percpu_counter_destroy(&mp->m_fdblocks);
1059 	ASSERT(xfs_is_shutdown(mp) ||
1060 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1061 	percpu_counter_destroy(&mp->m_delalloc_blks);
1062 	percpu_counter_destroy(&mp->m_frextents);
1063 }
1064 
1065 static int
1066 xfs_inodegc_init_percpu(
1067 	struct xfs_mount	*mp)
1068 {
1069 	struct xfs_inodegc	*gc;
1070 	int			cpu;
1071 
1072 	mp->m_inodegc = alloc_percpu(struct xfs_inodegc);
1073 	if (!mp->m_inodegc)
1074 		return -ENOMEM;
1075 
1076 	for_each_possible_cpu(cpu) {
1077 		gc = per_cpu_ptr(mp->m_inodegc, cpu);
1078 		init_llist_head(&gc->list);
1079 		gc->items = 0;
1080 		INIT_DELAYED_WORK(&gc->work, xfs_inodegc_worker);
1081 	}
1082 	return 0;
1083 }
1084 
1085 static void
1086 xfs_inodegc_free_percpu(
1087 	struct xfs_mount	*mp)
1088 {
1089 	if (!mp->m_inodegc)
1090 		return;
1091 	free_percpu(mp->m_inodegc);
1092 }
1093 
1094 static void
1095 xfs_fs_put_super(
1096 	struct super_block	*sb)
1097 {
1098 	struct xfs_mount	*mp = XFS_M(sb);
1099 
1100 	/* if ->fill_super failed, we have no mount to tear down */
1101 	if (!sb->s_fs_info)
1102 		return;
1103 
1104 	xfs_notice(mp, "Unmounting Filesystem");
1105 	xfs_filestream_unmount(mp);
1106 	xfs_unmountfs(mp);
1107 
1108 	xfs_freesb(mp);
1109 	free_percpu(mp->m_stats.xs_stats);
1110 	xfs_mount_list_del(mp);
1111 	xfs_inodegc_free_percpu(mp);
1112 	xfs_destroy_percpu_counters(mp);
1113 	xfs_destroy_mount_workqueues(mp);
1114 	xfs_close_devices(mp);
1115 
1116 	sb->s_fs_info = NULL;
1117 	xfs_mount_free(mp);
1118 }
1119 
1120 static long
1121 xfs_fs_nr_cached_objects(
1122 	struct super_block	*sb,
1123 	struct shrink_control	*sc)
1124 {
1125 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1126 	if (WARN_ON_ONCE(!sb->s_fs_info))
1127 		return 0;
1128 	return xfs_reclaim_inodes_count(XFS_M(sb));
1129 }
1130 
1131 static long
1132 xfs_fs_free_cached_objects(
1133 	struct super_block	*sb,
1134 	struct shrink_control	*sc)
1135 {
1136 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1137 }
1138 
1139 static const struct super_operations xfs_super_operations = {
1140 	.alloc_inode		= xfs_fs_alloc_inode,
1141 	.destroy_inode		= xfs_fs_destroy_inode,
1142 	.dirty_inode		= xfs_fs_dirty_inode,
1143 	.drop_inode		= xfs_fs_drop_inode,
1144 	.put_super		= xfs_fs_put_super,
1145 	.sync_fs		= xfs_fs_sync_fs,
1146 	.freeze_fs		= xfs_fs_freeze,
1147 	.unfreeze_fs		= xfs_fs_unfreeze,
1148 	.statfs			= xfs_fs_statfs,
1149 	.show_options		= xfs_fs_show_options,
1150 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1151 	.free_cached_objects	= xfs_fs_free_cached_objects,
1152 };
1153 
1154 static int
1155 suffix_kstrtoint(
1156 	const char	*s,
1157 	unsigned int	base,
1158 	int		*res)
1159 {
1160 	int		last, shift_left_factor = 0, _res;
1161 	char		*value;
1162 	int		ret = 0;
1163 
1164 	value = kstrdup(s, GFP_KERNEL);
1165 	if (!value)
1166 		return -ENOMEM;
1167 
1168 	last = strlen(value) - 1;
1169 	if (value[last] == 'K' || value[last] == 'k') {
1170 		shift_left_factor = 10;
1171 		value[last] = '\0';
1172 	}
1173 	if (value[last] == 'M' || value[last] == 'm') {
1174 		shift_left_factor = 20;
1175 		value[last] = '\0';
1176 	}
1177 	if (value[last] == 'G' || value[last] == 'g') {
1178 		shift_left_factor = 30;
1179 		value[last] = '\0';
1180 	}
1181 
1182 	if (kstrtoint(value, base, &_res))
1183 		ret = -EINVAL;
1184 	kfree(value);
1185 	*res = _res << shift_left_factor;
1186 	return ret;
1187 }
1188 
1189 static inline void
1190 xfs_fs_warn_deprecated(
1191 	struct fs_context	*fc,
1192 	struct fs_parameter	*param,
1193 	uint64_t		flag,
1194 	bool			value)
1195 {
1196 	/* Don't print the warning if reconfiguring and current mount point
1197 	 * already had the flag set
1198 	 */
1199 	if ((fc->purpose & FS_CONTEXT_FOR_RECONFIGURE) &&
1200             !!(XFS_M(fc->root->d_sb)->m_features & flag) == value)
1201 		return;
1202 	xfs_warn(fc->s_fs_info, "%s mount option is deprecated.", param->key);
1203 }
1204 
1205 /*
1206  * Set mount state from a mount option.
1207  *
1208  * NOTE: mp->m_super is NULL here!
1209  */
1210 static int
1211 xfs_fs_parse_param(
1212 	struct fs_context	*fc,
1213 	struct fs_parameter	*param)
1214 {
1215 	struct xfs_mount	*parsing_mp = fc->s_fs_info;
1216 	struct fs_parse_result	result;
1217 	int			size = 0;
1218 	int			opt;
1219 
1220 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1221 	if (opt < 0)
1222 		return opt;
1223 
1224 	switch (opt) {
1225 	case Opt_logbufs:
1226 		parsing_mp->m_logbufs = result.uint_32;
1227 		return 0;
1228 	case Opt_logbsize:
1229 		if (suffix_kstrtoint(param->string, 10, &parsing_mp->m_logbsize))
1230 			return -EINVAL;
1231 		return 0;
1232 	case Opt_logdev:
1233 		kfree(parsing_mp->m_logname);
1234 		parsing_mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1235 		if (!parsing_mp->m_logname)
1236 			return -ENOMEM;
1237 		return 0;
1238 	case Opt_rtdev:
1239 		kfree(parsing_mp->m_rtname);
1240 		parsing_mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1241 		if (!parsing_mp->m_rtname)
1242 			return -ENOMEM;
1243 		return 0;
1244 	case Opt_allocsize:
1245 		if (suffix_kstrtoint(param->string, 10, &size))
1246 			return -EINVAL;
1247 		parsing_mp->m_allocsize_log = ffs(size) - 1;
1248 		parsing_mp->m_features |= XFS_FEAT_ALLOCSIZE;
1249 		return 0;
1250 	case Opt_grpid:
1251 	case Opt_bsdgroups:
1252 		parsing_mp->m_features |= XFS_FEAT_GRPID;
1253 		return 0;
1254 	case Opt_nogrpid:
1255 	case Opt_sysvgroups:
1256 		parsing_mp->m_features &= ~XFS_FEAT_GRPID;
1257 		return 0;
1258 	case Opt_wsync:
1259 		parsing_mp->m_features |= XFS_FEAT_WSYNC;
1260 		return 0;
1261 	case Opt_norecovery:
1262 		parsing_mp->m_features |= XFS_FEAT_NORECOVERY;
1263 		return 0;
1264 	case Opt_noalign:
1265 		parsing_mp->m_features |= XFS_FEAT_NOALIGN;
1266 		return 0;
1267 	case Opt_swalloc:
1268 		parsing_mp->m_features |= XFS_FEAT_SWALLOC;
1269 		return 0;
1270 	case Opt_sunit:
1271 		parsing_mp->m_dalign = result.uint_32;
1272 		return 0;
1273 	case Opt_swidth:
1274 		parsing_mp->m_swidth = result.uint_32;
1275 		return 0;
1276 	case Opt_inode32:
1277 		parsing_mp->m_features |= XFS_FEAT_SMALL_INUMS;
1278 		return 0;
1279 	case Opt_inode64:
1280 		parsing_mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1281 		return 0;
1282 	case Opt_nouuid:
1283 		parsing_mp->m_features |= XFS_FEAT_NOUUID;
1284 		return 0;
1285 	case Opt_largeio:
1286 		parsing_mp->m_features |= XFS_FEAT_LARGE_IOSIZE;
1287 		return 0;
1288 	case Opt_nolargeio:
1289 		parsing_mp->m_features &= ~XFS_FEAT_LARGE_IOSIZE;
1290 		return 0;
1291 	case Opt_filestreams:
1292 		parsing_mp->m_features |= XFS_FEAT_FILESTREAMS;
1293 		return 0;
1294 	case Opt_noquota:
1295 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1296 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1297 		return 0;
1298 	case Opt_quota:
1299 	case Opt_uquota:
1300 	case Opt_usrquota:
1301 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ENFD);
1302 		return 0;
1303 	case Opt_qnoenforce:
1304 	case Opt_uqnoenforce:
1305 		parsing_mp->m_qflags |= XFS_UQUOTA_ACCT;
1306 		parsing_mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1307 		return 0;
1308 	case Opt_pquota:
1309 	case Opt_prjquota:
1310 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ENFD);
1311 		return 0;
1312 	case Opt_pqnoenforce:
1313 		parsing_mp->m_qflags |= XFS_PQUOTA_ACCT;
1314 		parsing_mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1315 		return 0;
1316 	case Opt_gquota:
1317 	case Opt_grpquota:
1318 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ENFD);
1319 		return 0;
1320 	case Opt_gqnoenforce:
1321 		parsing_mp->m_qflags |= XFS_GQUOTA_ACCT;
1322 		parsing_mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1323 		return 0;
1324 	case Opt_discard:
1325 		parsing_mp->m_features |= XFS_FEAT_DISCARD;
1326 		return 0;
1327 	case Opt_nodiscard:
1328 		parsing_mp->m_features &= ~XFS_FEAT_DISCARD;
1329 		return 0;
1330 #ifdef CONFIG_FS_DAX
1331 	case Opt_dax:
1332 		xfs_mount_set_dax_mode(parsing_mp, XFS_DAX_ALWAYS);
1333 		return 0;
1334 	case Opt_dax_enum:
1335 		xfs_mount_set_dax_mode(parsing_mp, result.uint_32);
1336 		return 0;
1337 #endif
1338 	/* Following mount options will be removed in September 2025 */
1339 	case Opt_ikeep:
1340 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, true);
1341 		parsing_mp->m_features |= XFS_FEAT_IKEEP;
1342 		return 0;
1343 	case Opt_noikeep:
1344 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, false);
1345 		parsing_mp->m_features &= ~XFS_FEAT_IKEEP;
1346 		return 0;
1347 	case Opt_attr2:
1348 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_ATTR2, true);
1349 		parsing_mp->m_features |= XFS_FEAT_ATTR2;
1350 		return 0;
1351 	case Opt_noattr2:
1352 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_NOATTR2, true);
1353 		parsing_mp->m_features |= XFS_FEAT_NOATTR2;
1354 		return 0;
1355 	default:
1356 		xfs_warn(parsing_mp, "unknown mount option [%s].", param->key);
1357 		return -EINVAL;
1358 	}
1359 
1360 	return 0;
1361 }
1362 
1363 static int
1364 xfs_fs_validate_params(
1365 	struct xfs_mount	*mp)
1366 {
1367 	/* No recovery flag requires a read-only mount */
1368 	if (xfs_has_norecovery(mp) && !xfs_is_readonly(mp)) {
1369 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1370 		return -EINVAL;
1371 	}
1372 
1373 	/*
1374 	 * We have not read the superblock at this point, so only the attr2
1375 	 * mount option can set the attr2 feature by this stage.
1376 	 */
1377 	if (xfs_has_attr2(mp) && xfs_has_noattr2(mp)) {
1378 		xfs_warn(mp, "attr2 and noattr2 cannot both be specified.");
1379 		return -EINVAL;
1380 	}
1381 
1382 
1383 	if (xfs_has_noalign(mp) && (mp->m_dalign || mp->m_swidth)) {
1384 		xfs_warn(mp,
1385 	"sunit and swidth options incompatible with the noalign option");
1386 		return -EINVAL;
1387 	}
1388 
1389 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1390 		xfs_warn(mp, "quota support not available in this kernel.");
1391 		return -EINVAL;
1392 	}
1393 
1394 	if ((mp->m_dalign && !mp->m_swidth) ||
1395 	    (!mp->m_dalign && mp->m_swidth)) {
1396 		xfs_warn(mp, "sunit and swidth must be specified together");
1397 		return -EINVAL;
1398 	}
1399 
1400 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1401 		xfs_warn(mp,
1402 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1403 			mp->m_swidth, mp->m_dalign);
1404 		return -EINVAL;
1405 	}
1406 
1407 	if (mp->m_logbufs != -1 &&
1408 	    mp->m_logbufs != 0 &&
1409 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1410 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1411 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1412 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1413 		return -EINVAL;
1414 	}
1415 
1416 	if (mp->m_logbsize != -1 &&
1417 	    mp->m_logbsize !=  0 &&
1418 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1419 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1420 	     !is_power_of_2(mp->m_logbsize))) {
1421 		xfs_warn(mp,
1422 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1423 			mp->m_logbsize);
1424 		return -EINVAL;
1425 	}
1426 
1427 	if (xfs_has_allocsize(mp) &&
1428 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1429 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1430 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1431 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1432 		return -EINVAL;
1433 	}
1434 
1435 	return 0;
1436 }
1437 
1438 static int
1439 xfs_fs_fill_super(
1440 	struct super_block	*sb,
1441 	struct fs_context	*fc)
1442 {
1443 	struct xfs_mount	*mp = sb->s_fs_info;
1444 	struct inode		*root;
1445 	int			flags = 0, error;
1446 
1447 	mp->m_super = sb;
1448 
1449 	error = xfs_fs_validate_params(mp);
1450 	if (error)
1451 		goto out_free_names;
1452 
1453 	sb_min_blocksize(sb, BBSIZE);
1454 	sb->s_xattr = xfs_xattr_handlers;
1455 	sb->s_export_op = &xfs_export_operations;
1456 #ifdef CONFIG_XFS_QUOTA
1457 	sb->s_qcop = &xfs_quotactl_operations;
1458 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1459 #endif
1460 	sb->s_op = &xfs_super_operations;
1461 
1462 	/*
1463 	 * Delay mount work if the debug hook is set. This is debug
1464 	 * instrumention to coordinate simulation of xfs mount failures with
1465 	 * VFS superblock operations
1466 	 */
1467 	if (xfs_globals.mount_delay) {
1468 		xfs_notice(mp, "Delaying mount for %d seconds.",
1469 			xfs_globals.mount_delay);
1470 		msleep(xfs_globals.mount_delay * 1000);
1471 	}
1472 
1473 	if (fc->sb_flags & SB_SILENT)
1474 		flags |= XFS_MFSI_QUIET;
1475 
1476 	error = xfs_open_devices(mp);
1477 	if (error)
1478 		goto out_free_names;
1479 
1480 	error = xfs_init_mount_workqueues(mp);
1481 	if (error)
1482 		goto out_close_devices;
1483 
1484 	error = xfs_init_percpu_counters(mp);
1485 	if (error)
1486 		goto out_destroy_workqueues;
1487 
1488 	error = xfs_inodegc_init_percpu(mp);
1489 	if (error)
1490 		goto out_destroy_counters;
1491 
1492 	/*
1493 	 * All percpu data structures requiring cleanup when a cpu goes offline
1494 	 * must be allocated before adding this @mp to the cpu-dead handler's
1495 	 * mount list.
1496 	 */
1497 	xfs_mount_list_add(mp);
1498 
1499 	/* Allocate stats memory before we do operations that might use it */
1500 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1501 	if (!mp->m_stats.xs_stats) {
1502 		error = -ENOMEM;
1503 		goto out_destroy_inodegc;
1504 	}
1505 
1506 	error = xfs_readsb(mp, flags);
1507 	if (error)
1508 		goto out_free_stats;
1509 
1510 	error = xfs_finish_flags(mp);
1511 	if (error)
1512 		goto out_free_sb;
1513 
1514 	error = xfs_setup_devices(mp);
1515 	if (error)
1516 		goto out_free_sb;
1517 
1518 	/* V4 support is undergoing deprecation. */
1519 	if (!xfs_has_crc(mp)) {
1520 #ifdef CONFIG_XFS_SUPPORT_V4
1521 		xfs_warn_once(mp,
1522 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1523 #else
1524 		xfs_warn(mp,
1525 	"Deprecated V4 format (crc=0) not supported by kernel.");
1526 		error = -EINVAL;
1527 		goto out_free_sb;
1528 #endif
1529 	}
1530 
1531 	/* Filesystem claims it needs repair, so refuse the mount. */
1532 	if (xfs_has_needsrepair(mp)) {
1533 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1534 		error = -EFSCORRUPTED;
1535 		goto out_free_sb;
1536 	}
1537 
1538 	/*
1539 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1540 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1541 	 * we don't check them at all.
1542 	 */
1543 	if (mp->m_sb.sb_inprogress) {
1544 		xfs_warn(mp, "Offline file system operation in progress!");
1545 		error = -EFSCORRUPTED;
1546 		goto out_free_sb;
1547 	}
1548 
1549 	/*
1550 	 * Until this is fixed only page-sized or smaller data blocks work.
1551 	 */
1552 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1553 		xfs_warn(mp,
1554 		"File system with blocksize %d bytes. "
1555 		"Only pagesize (%ld) or less will currently work.",
1556 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1557 		error = -ENOSYS;
1558 		goto out_free_sb;
1559 	}
1560 
1561 	/* Ensure this filesystem fits in the page cache limits */
1562 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1563 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1564 		xfs_warn(mp,
1565 		"file system too large to be mounted on this system.");
1566 		error = -EFBIG;
1567 		goto out_free_sb;
1568 	}
1569 
1570 	/*
1571 	 * XFS block mappings use 54 bits to store the logical block offset.
1572 	 * This should suffice to handle the maximum file size that the VFS
1573 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1574 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1575 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1576 	 * to check this assertion.
1577 	 *
1578 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1579 	 * maximum pagecache offset in units of fs blocks.
1580 	 */
1581 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1582 		xfs_warn(mp,
1583 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1584 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1585 			 XFS_MAX_FILEOFF);
1586 		error = -EINVAL;
1587 		goto out_free_sb;
1588 	}
1589 
1590 	error = xfs_filestream_mount(mp);
1591 	if (error)
1592 		goto out_free_sb;
1593 
1594 	/*
1595 	 * we must configure the block size in the superblock before we run the
1596 	 * full mount process as the mount process can lookup and cache inodes.
1597 	 */
1598 	sb->s_magic = XFS_SUPER_MAGIC;
1599 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1600 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1601 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1602 	sb->s_max_links = XFS_MAXLINK;
1603 	sb->s_time_gran = 1;
1604 	if (xfs_has_bigtime(mp)) {
1605 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1606 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1607 	} else {
1608 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1609 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1610 	}
1611 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1612 	sb->s_iflags |= SB_I_CGROUPWB;
1613 
1614 	set_posix_acl_flag(sb);
1615 
1616 	/* version 5 superblocks support inode version counters. */
1617 	if (xfs_has_crc(mp))
1618 		sb->s_flags |= SB_I_VERSION;
1619 
1620 	if (xfs_has_dax_always(mp)) {
1621 		error = xfs_setup_dax_always(mp);
1622 		if (error)
1623 			goto out_filestream_unmount;
1624 	}
1625 
1626 	if (xfs_has_discard(mp) && !bdev_max_discard_sectors(sb->s_bdev)) {
1627 		xfs_warn(mp,
1628 	"mounting with \"discard\" option, but the device does not support discard");
1629 		mp->m_features &= ~XFS_FEAT_DISCARD;
1630 	}
1631 
1632 	if (xfs_has_reflink(mp)) {
1633 		if (mp->m_sb.sb_rblocks) {
1634 			xfs_alert(mp,
1635 	"reflink not compatible with realtime device!");
1636 			error = -EINVAL;
1637 			goto out_filestream_unmount;
1638 		}
1639 
1640 		if (xfs_globals.always_cow) {
1641 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1642 			mp->m_always_cow = true;
1643 		}
1644 	}
1645 
1646 	if (xfs_has_rmapbt(mp) && mp->m_sb.sb_rblocks) {
1647 		xfs_alert(mp,
1648 	"reverse mapping btree not compatible with realtime device!");
1649 		error = -EINVAL;
1650 		goto out_filestream_unmount;
1651 	}
1652 
1653 	if (xfs_has_large_extent_counts(mp))
1654 		xfs_warn(mp,
1655 	"EXPERIMENTAL Large extent counts feature in use. Use at your own risk!");
1656 
1657 	error = xfs_mountfs(mp);
1658 	if (error)
1659 		goto out_filestream_unmount;
1660 
1661 	root = igrab(VFS_I(mp->m_rootip));
1662 	if (!root) {
1663 		error = -ENOENT;
1664 		goto out_unmount;
1665 	}
1666 	sb->s_root = d_make_root(root);
1667 	if (!sb->s_root) {
1668 		error = -ENOMEM;
1669 		goto out_unmount;
1670 	}
1671 
1672 	return 0;
1673 
1674  out_filestream_unmount:
1675 	xfs_filestream_unmount(mp);
1676  out_free_sb:
1677 	xfs_freesb(mp);
1678  out_free_stats:
1679 	free_percpu(mp->m_stats.xs_stats);
1680  out_destroy_inodegc:
1681 	xfs_mount_list_del(mp);
1682 	xfs_inodegc_free_percpu(mp);
1683  out_destroy_counters:
1684 	xfs_destroy_percpu_counters(mp);
1685  out_destroy_workqueues:
1686 	xfs_destroy_mount_workqueues(mp);
1687  out_close_devices:
1688 	xfs_close_devices(mp);
1689  out_free_names:
1690 	sb->s_fs_info = NULL;
1691 	xfs_mount_free(mp);
1692 	return error;
1693 
1694  out_unmount:
1695 	xfs_filestream_unmount(mp);
1696 	xfs_unmountfs(mp);
1697 	goto out_free_sb;
1698 }
1699 
1700 static int
1701 xfs_fs_get_tree(
1702 	struct fs_context	*fc)
1703 {
1704 	return get_tree_bdev(fc, xfs_fs_fill_super);
1705 }
1706 
1707 static int
1708 xfs_remount_rw(
1709 	struct xfs_mount	*mp)
1710 {
1711 	struct xfs_sb		*sbp = &mp->m_sb;
1712 	int error;
1713 
1714 	if (xfs_has_norecovery(mp)) {
1715 		xfs_warn(mp,
1716 			"ro->rw transition prohibited on norecovery mount");
1717 		return -EINVAL;
1718 	}
1719 
1720 	if (xfs_sb_is_v5(sbp) &&
1721 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1722 		xfs_warn(mp,
1723 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1724 			(sbp->sb_features_ro_compat &
1725 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1726 		return -EINVAL;
1727 	}
1728 
1729 	clear_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1730 
1731 	/*
1732 	 * If this is the first remount to writeable state we might have some
1733 	 * superblock changes to update.
1734 	 */
1735 	if (mp->m_update_sb) {
1736 		error = xfs_sync_sb(mp, false);
1737 		if (error) {
1738 			xfs_warn(mp, "failed to write sb changes");
1739 			return error;
1740 		}
1741 		mp->m_update_sb = false;
1742 	}
1743 
1744 	/*
1745 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1746 	 * it is non-zero, otherwise go with the default.
1747 	 */
1748 	xfs_restore_resvblks(mp);
1749 	xfs_log_work_queue(mp);
1750 	xfs_blockgc_start(mp);
1751 
1752 	/* Create the per-AG metadata reservation pool .*/
1753 	error = xfs_fs_reserve_ag_blocks(mp);
1754 	if (error && error != -ENOSPC)
1755 		return error;
1756 
1757 	/* Re-enable the background inode inactivation worker. */
1758 	xfs_inodegc_start(mp);
1759 
1760 	return 0;
1761 }
1762 
1763 static int
1764 xfs_remount_ro(
1765 	struct xfs_mount	*mp)
1766 {
1767 	struct xfs_icwalk	icw = {
1768 		.icw_flags	= XFS_ICWALK_FLAG_SYNC,
1769 	};
1770 	int			error;
1771 
1772 	/* Flush all the dirty data to disk. */
1773 	error = sync_filesystem(mp->m_super);
1774 	if (error)
1775 		return error;
1776 
1777 	/*
1778 	 * Cancel background eofb scanning so it cannot race with the final
1779 	 * log force+buftarg wait and deadlock the remount.
1780 	 */
1781 	xfs_blockgc_stop(mp);
1782 
1783 	/*
1784 	 * Clear out all remaining COW staging extents and speculative post-EOF
1785 	 * preallocations so that we don't leave inodes requiring inactivation
1786 	 * cleanups during reclaim on a read-only mount.  We must process every
1787 	 * cached inode, so this requires a synchronous cache scan.
1788 	 */
1789 	error = xfs_blockgc_free_space(mp, &icw);
1790 	if (error) {
1791 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1792 		return error;
1793 	}
1794 
1795 	/*
1796 	 * Stop the inodegc background worker.  xfs_fs_reconfigure already
1797 	 * flushed all pending inodegc work when it sync'd the filesystem.
1798 	 * The VFS holds s_umount, so we know that inodes cannot enter
1799 	 * xfs_fs_destroy_inode during a remount operation.  In readonly mode
1800 	 * we send inodes straight to reclaim, so no inodes will be queued.
1801 	 */
1802 	xfs_inodegc_stop(mp);
1803 
1804 	/* Free the per-AG metadata reservation pool. */
1805 	error = xfs_fs_unreserve_ag_blocks(mp);
1806 	if (error) {
1807 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1808 		return error;
1809 	}
1810 
1811 	/*
1812 	 * Before we sync the metadata, we need to free up the reserve block
1813 	 * pool so that the used block count in the superblock on disk is
1814 	 * correct at the end of the remount. Stash the current* reserve pool
1815 	 * size so that if we get remounted rw, we can return it to the same
1816 	 * size.
1817 	 */
1818 	xfs_save_resvblks(mp);
1819 
1820 	xfs_log_clean(mp);
1821 	set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1822 
1823 	return 0;
1824 }
1825 
1826 /*
1827  * Logically we would return an error here to prevent users from believing
1828  * they might have changed mount options using remount which can't be changed.
1829  *
1830  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1831  * arguments in some cases so we can't blindly reject options, but have to
1832  * check for each specified option if it actually differs from the currently
1833  * set option and only reject it if that's the case.
1834  *
1835  * Until that is implemented we return success for every remount request, and
1836  * silently ignore all options that we can't actually change.
1837  */
1838 static int
1839 xfs_fs_reconfigure(
1840 	struct fs_context *fc)
1841 {
1842 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1843 	struct xfs_mount        *new_mp = fc->s_fs_info;
1844 	int			flags = fc->sb_flags;
1845 	int			error;
1846 
1847 	/* version 5 superblocks always support version counters. */
1848 	if (xfs_has_crc(mp))
1849 		fc->sb_flags |= SB_I_VERSION;
1850 
1851 	error = xfs_fs_validate_params(new_mp);
1852 	if (error)
1853 		return error;
1854 
1855 	/* inode32 -> inode64 */
1856 	if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
1857 		mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1858 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1859 	}
1860 
1861 	/* inode64 -> inode32 */
1862 	if (!xfs_has_small_inums(mp) && xfs_has_small_inums(new_mp)) {
1863 		mp->m_features |= XFS_FEAT_SMALL_INUMS;
1864 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1865 	}
1866 
1867 	/* ro -> rw */
1868 	if (xfs_is_readonly(mp) && !(flags & SB_RDONLY)) {
1869 		error = xfs_remount_rw(mp);
1870 		if (error)
1871 			return error;
1872 	}
1873 
1874 	/* rw -> ro */
1875 	if (!xfs_is_readonly(mp) && (flags & SB_RDONLY)) {
1876 		error = xfs_remount_ro(mp);
1877 		if (error)
1878 			return error;
1879 	}
1880 
1881 	return 0;
1882 }
1883 
1884 static void xfs_fs_free(
1885 	struct fs_context	*fc)
1886 {
1887 	struct xfs_mount	*mp = fc->s_fs_info;
1888 
1889 	/*
1890 	 * mp is stored in the fs_context when it is initialized.
1891 	 * mp is transferred to the superblock on a successful mount,
1892 	 * but if an error occurs before the transfer we have to free
1893 	 * it here.
1894 	 */
1895 	if (mp)
1896 		xfs_mount_free(mp);
1897 }
1898 
1899 static const struct fs_context_operations xfs_context_ops = {
1900 	.parse_param = xfs_fs_parse_param,
1901 	.get_tree    = xfs_fs_get_tree,
1902 	.reconfigure = xfs_fs_reconfigure,
1903 	.free        = xfs_fs_free,
1904 };
1905 
1906 static int xfs_init_fs_context(
1907 	struct fs_context	*fc)
1908 {
1909 	struct xfs_mount	*mp;
1910 
1911 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1912 	if (!mp)
1913 		return -ENOMEM;
1914 
1915 	spin_lock_init(&mp->m_sb_lock);
1916 	spin_lock_init(&mp->m_agirotor_lock);
1917 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1918 	spin_lock_init(&mp->m_perag_lock);
1919 	mutex_init(&mp->m_growlock);
1920 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1921 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1922 	mp->m_kobj.kobject.kset = xfs_kset;
1923 	/*
1924 	 * We don't create the finobt per-ag space reservation until after log
1925 	 * recovery, so we must set this to true so that an ifree transaction
1926 	 * started during log recovery will not depend on space reservations
1927 	 * for finobt expansion.
1928 	 */
1929 	mp->m_finobt_nores = true;
1930 
1931 	/*
1932 	 * These can be overridden by the mount option parsing.
1933 	 */
1934 	mp->m_logbufs = -1;
1935 	mp->m_logbsize = -1;
1936 	mp->m_allocsize_log = 16; /* 64k */
1937 
1938 	/*
1939 	 * Copy binary VFS mount flags we are interested in.
1940 	 */
1941 	if (fc->sb_flags & SB_RDONLY)
1942 		set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1943 	if (fc->sb_flags & SB_DIRSYNC)
1944 		mp->m_features |= XFS_FEAT_DIRSYNC;
1945 	if (fc->sb_flags & SB_SYNCHRONOUS)
1946 		mp->m_features |= XFS_FEAT_WSYNC;
1947 
1948 	fc->s_fs_info = mp;
1949 	fc->ops = &xfs_context_ops;
1950 
1951 	return 0;
1952 }
1953 
1954 static struct file_system_type xfs_fs_type = {
1955 	.owner			= THIS_MODULE,
1956 	.name			= "xfs",
1957 	.init_fs_context	= xfs_init_fs_context,
1958 	.parameters		= xfs_fs_parameters,
1959 	.kill_sb		= kill_block_super,
1960 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1961 };
1962 MODULE_ALIAS_FS("xfs");
1963 
1964 STATIC int __init
1965 xfs_init_caches(void)
1966 {
1967 	int		error;
1968 
1969 	xfs_log_ticket_cache = kmem_cache_create("xfs_log_ticket",
1970 						sizeof(struct xlog_ticket),
1971 						0, 0, NULL);
1972 	if (!xfs_log_ticket_cache)
1973 		goto out;
1974 
1975 	error = xfs_btree_init_cur_caches();
1976 	if (error)
1977 		goto out_destroy_log_ticket_cache;
1978 
1979 	error = xfs_defer_init_item_caches();
1980 	if (error)
1981 		goto out_destroy_btree_cur_cache;
1982 
1983 	xfs_da_state_cache = kmem_cache_create("xfs_da_state",
1984 					      sizeof(struct xfs_da_state),
1985 					      0, 0, NULL);
1986 	if (!xfs_da_state_cache)
1987 		goto out_destroy_defer_item_cache;
1988 
1989 	xfs_ifork_cache = kmem_cache_create("xfs_ifork",
1990 					   sizeof(struct xfs_ifork),
1991 					   0, 0, NULL);
1992 	if (!xfs_ifork_cache)
1993 		goto out_destroy_da_state_cache;
1994 
1995 	xfs_trans_cache = kmem_cache_create("xfs_trans",
1996 					   sizeof(struct xfs_trans),
1997 					   0, 0, NULL);
1998 	if (!xfs_trans_cache)
1999 		goto out_destroy_ifork_cache;
2000 
2001 
2002 	/*
2003 	 * The size of the cache-allocated buf log item is the maximum
2004 	 * size possible under XFS.  This wastes a little bit of memory,
2005 	 * but it is much faster.
2006 	 */
2007 	xfs_buf_item_cache = kmem_cache_create("xfs_buf_item",
2008 					      sizeof(struct xfs_buf_log_item),
2009 					      0, 0, NULL);
2010 	if (!xfs_buf_item_cache)
2011 		goto out_destroy_trans_cache;
2012 
2013 	xfs_efd_cache = kmem_cache_create("xfs_efd_item",
2014 					(sizeof(struct xfs_efd_log_item) +
2015 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
2016 					sizeof(struct xfs_extent)),
2017 					0, 0, NULL);
2018 	if (!xfs_efd_cache)
2019 		goto out_destroy_buf_item_cache;
2020 
2021 	xfs_efi_cache = kmem_cache_create("xfs_efi_item",
2022 					 (sizeof(struct xfs_efi_log_item) +
2023 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
2024 					 sizeof(struct xfs_extent)),
2025 					 0, 0, NULL);
2026 	if (!xfs_efi_cache)
2027 		goto out_destroy_efd_cache;
2028 
2029 	xfs_inode_cache = kmem_cache_create("xfs_inode",
2030 					   sizeof(struct xfs_inode), 0,
2031 					   (SLAB_HWCACHE_ALIGN |
2032 					    SLAB_RECLAIM_ACCOUNT |
2033 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
2034 					   xfs_fs_inode_init_once);
2035 	if (!xfs_inode_cache)
2036 		goto out_destroy_efi_cache;
2037 
2038 	xfs_ili_cache = kmem_cache_create("xfs_ili",
2039 					 sizeof(struct xfs_inode_log_item), 0,
2040 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
2041 					 NULL);
2042 	if (!xfs_ili_cache)
2043 		goto out_destroy_inode_cache;
2044 
2045 	xfs_icreate_cache = kmem_cache_create("xfs_icr",
2046 					     sizeof(struct xfs_icreate_item),
2047 					     0, 0, NULL);
2048 	if (!xfs_icreate_cache)
2049 		goto out_destroy_ili_cache;
2050 
2051 	xfs_rud_cache = kmem_cache_create("xfs_rud_item",
2052 					 sizeof(struct xfs_rud_log_item),
2053 					 0, 0, NULL);
2054 	if (!xfs_rud_cache)
2055 		goto out_destroy_icreate_cache;
2056 
2057 	xfs_rui_cache = kmem_cache_create("xfs_rui_item",
2058 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
2059 			0, 0, NULL);
2060 	if (!xfs_rui_cache)
2061 		goto out_destroy_rud_cache;
2062 
2063 	xfs_cud_cache = kmem_cache_create("xfs_cud_item",
2064 					 sizeof(struct xfs_cud_log_item),
2065 					 0, 0, NULL);
2066 	if (!xfs_cud_cache)
2067 		goto out_destroy_rui_cache;
2068 
2069 	xfs_cui_cache = kmem_cache_create("xfs_cui_item",
2070 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2071 			0, 0, NULL);
2072 	if (!xfs_cui_cache)
2073 		goto out_destroy_cud_cache;
2074 
2075 	xfs_bud_cache = kmem_cache_create("xfs_bud_item",
2076 					 sizeof(struct xfs_bud_log_item),
2077 					 0, 0, NULL);
2078 	if (!xfs_bud_cache)
2079 		goto out_destroy_cui_cache;
2080 
2081 	xfs_bui_cache = kmem_cache_create("xfs_bui_item",
2082 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2083 			0, 0, NULL);
2084 	if (!xfs_bui_cache)
2085 		goto out_destroy_bud_cache;
2086 
2087 	xfs_attrd_cache = kmem_cache_create("xfs_attrd_item",
2088 					    sizeof(struct xfs_attrd_log_item),
2089 					    0, 0, NULL);
2090 	if (!xfs_attrd_cache)
2091 		goto out_destroy_bui_cache;
2092 
2093 	xfs_attri_cache = kmem_cache_create("xfs_attri_item",
2094 					    sizeof(struct xfs_attri_log_item),
2095 					    0, 0, NULL);
2096 	if (!xfs_attri_cache)
2097 		goto out_destroy_attrd_cache;
2098 
2099 	return 0;
2100 
2101  out_destroy_attrd_cache:
2102 	kmem_cache_destroy(xfs_attrd_cache);
2103  out_destroy_bui_cache:
2104 	kmem_cache_destroy(xfs_bui_cache);
2105  out_destroy_bud_cache:
2106 	kmem_cache_destroy(xfs_bud_cache);
2107  out_destroy_cui_cache:
2108 	kmem_cache_destroy(xfs_cui_cache);
2109  out_destroy_cud_cache:
2110 	kmem_cache_destroy(xfs_cud_cache);
2111  out_destroy_rui_cache:
2112 	kmem_cache_destroy(xfs_rui_cache);
2113  out_destroy_rud_cache:
2114 	kmem_cache_destroy(xfs_rud_cache);
2115  out_destroy_icreate_cache:
2116 	kmem_cache_destroy(xfs_icreate_cache);
2117  out_destroy_ili_cache:
2118 	kmem_cache_destroy(xfs_ili_cache);
2119  out_destroy_inode_cache:
2120 	kmem_cache_destroy(xfs_inode_cache);
2121  out_destroy_efi_cache:
2122 	kmem_cache_destroy(xfs_efi_cache);
2123  out_destroy_efd_cache:
2124 	kmem_cache_destroy(xfs_efd_cache);
2125  out_destroy_buf_item_cache:
2126 	kmem_cache_destroy(xfs_buf_item_cache);
2127  out_destroy_trans_cache:
2128 	kmem_cache_destroy(xfs_trans_cache);
2129  out_destroy_ifork_cache:
2130 	kmem_cache_destroy(xfs_ifork_cache);
2131  out_destroy_da_state_cache:
2132 	kmem_cache_destroy(xfs_da_state_cache);
2133  out_destroy_defer_item_cache:
2134 	xfs_defer_destroy_item_caches();
2135  out_destroy_btree_cur_cache:
2136 	xfs_btree_destroy_cur_caches();
2137  out_destroy_log_ticket_cache:
2138 	kmem_cache_destroy(xfs_log_ticket_cache);
2139  out:
2140 	return -ENOMEM;
2141 }
2142 
2143 STATIC void
2144 xfs_destroy_caches(void)
2145 {
2146 	/*
2147 	 * Make sure all delayed rcu free are flushed before we
2148 	 * destroy caches.
2149 	 */
2150 	rcu_barrier();
2151 	kmem_cache_destroy(xfs_attri_cache);
2152 	kmem_cache_destroy(xfs_attrd_cache);
2153 	kmem_cache_destroy(xfs_bui_cache);
2154 	kmem_cache_destroy(xfs_bud_cache);
2155 	kmem_cache_destroy(xfs_cui_cache);
2156 	kmem_cache_destroy(xfs_cud_cache);
2157 	kmem_cache_destroy(xfs_rui_cache);
2158 	kmem_cache_destroy(xfs_rud_cache);
2159 	kmem_cache_destroy(xfs_icreate_cache);
2160 	kmem_cache_destroy(xfs_ili_cache);
2161 	kmem_cache_destroy(xfs_inode_cache);
2162 	kmem_cache_destroy(xfs_efi_cache);
2163 	kmem_cache_destroy(xfs_efd_cache);
2164 	kmem_cache_destroy(xfs_buf_item_cache);
2165 	kmem_cache_destroy(xfs_trans_cache);
2166 	kmem_cache_destroy(xfs_ifork_cache);
2167 	kmem_cache_destroy(xfs_da_state_cache);
2168 	xfs_defer_destroy_item_caches();
2169 	xfs_btree_destroy_cur_caches();
2170 	kmem_cache_destroy(xfs_log_ticket_cache);
2171 }
2172 
2173 STATIC int __init
2174 xfs_init_workqueues(void)
2175 {
2176 	/*
2177 	 * The allocation workqueue can be used in memory reclaim situations
2178 	 * (writepage path), and parallelism is only limited by the number of
2179 	 * AGs in all the filesystems mounted. Hence use the default large
2180 	 * max_active value for this workqueue.
2181 	 */
2182 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2183 			XFS_WQFLAGS(WQ_MEM_RECLAIM | WQ_FREEZABLE), 0);
2184 	if (!xfs_alloc_wq)
2185 		return -ENOMEM;
2186 
2187 	xfs_discard_wq = alloc_workqueue("xfsdiscard", XFS_WQFLAGS(WQ_UNBOUND),
2188 			0);
2189 	if (!xfs_discard_wq)
2190 		goto out_free_alloc_wq;
2191 
2192 	return 0;
2193 out_free_alloc_wq:
2194 	destroy_workqueue(xfs_alloc_wq);
2195 	return -ENOMEM;
2196 }
2197 
2198 STATIC void
2199 xfs_destroy_workqueues(void)
2200 {
2201 	destroy_workqueue(xfs_discard_wq);
2202 	destroy_workqueue(xfs_alloc_wq);
2203 }
2204 
2205 #ifdef CONFIG_HOTPLUG_CPU
2206 static int
2207 xfs_cpu_dead(
2208 	unsigned int		cpu)
2209 {
2210 	struct xfs_mount	*mp, *n;
2211 
2212 	spin_lock(&xfs_mount_list_lock);
2213 	list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
2214 		spin_unlock(&xfs_mount_list_lock);
2215 		xfs_inodegc_cpu_dead(mp, cpu);
2216 		spin_lock(&xfs_mount_list_lock);
2217 	}
2218 	spin_unlock(&xfs_mount_list_lock);
2219 	return 0;
2220 }
2221 
2222 static int __init
2223 xfs_cpu_hotplug_init(void)
2224 {
2225 	int	error;
2226 
2227 	error = cpuhp_setup_state_nocalls(CPUHP_XFS_DEAD, "xfs:dead", NULL,
2228 			xfs_cpu_dead);
2229 	if (error < 0)
2230 		xfs_alert(NULL,
2231 "Failed to initialise CPU hotplug, error %d. XFS is non-functional.",
2232 			error);
2233 	return error;
2234 }
2235 
2236 static void
2237 xfs_cpu_hotplug_destroy(void)
2238 {
2239 	cpuhp_remove_state_nocalls(CPUHP_XFS_DEAD);
2240 }
2241 
2242 #else /* !CONFIG_HOTPLUG_CPU */
2243 static inline int xfs_cpu_hotplug_init(void) { return 0; }
2244 static inline void xfs_cpu_hotplug_destroy(void) {}
2245 #endif
2246 
2247 STATIC int __init
2248 init_xfs_fs(void)
2249 {
2250 	int			error;
2251 
2252 	xfs_check_ondisk_structs();
2253 
2254 	printk(KERN_INFO XFS_VERSION_STRING " with "
2255 			 XFS_BUILD_OPTIONS " enabled\n");
2256 
2257 	xfs_dir_startup();
2258 
2259 	error = xfs_cpu_hotplug_init();
2260 	if (error)
2261 		goto out;
2262 
2263 	error = xfs_init_caches();
2264 	if (error)
2265 		goto out_destroy_hp;
2266 
2267 	error = xfs_init_workqueues();
2268 	if (error)
2269 		goto out_destroy_caches;
2270 
2271 	error = xfs_mru_cache_init();
2272 	if (error)
2273 		goto out_destroy_wq;
2274 
2275 	error = xfs_buf_init();
2276 	if (error)
2277 		goto out_mru_cache_uninit;
2278 
2279 	error = xfs_init_procfs();
2280 	if (error)
2281 		goto out_buf_terminate;
2282 
2283 	error = xfs_sysctl_register();
2284 	if (error)
2285 		goto out_cleanup_procfs;
2286 
2287 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2288 	if (!xfs_kset) {
2289 		error = -ENOMEM;
2290 		goto out_sysctl_unregister;
2291 	}
2292 
2293 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2294 
2295 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2296 	if (!xfsstats.xs_stats) {
2297 		error = -ENOMEM;
2298 		goto out_kset_unregister;
2299 	}
2300 
2301 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2302 			       "stats");
2303 	if (error)
2304 		goto out_free_stats;
2305 
2306 #ifdef DEBUG
2307 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2308 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2309 	if (error)
2310 		goto out_remove_stats_kobj;
2311 #endif
2312 
2313 	error = xfs_qm_init();
2314 	if (error)
2315 		goto out_remove_dbg_kobj;
2316 
2317 	error = register_filesystem(&xfs_fs_type);
2318 	if (error)
2319 		goto out_qm_exit;
2320 	return 0;
2321 
2322  out_qm_exit:
2323 	xfs_qm_exit();
2324  out_remove_dbg_kobj:
2325 #ifdef DEBUG
2326 	xfs_sysfs_del(&xfs_dbg_kobj);
2327  out_remove_stats_kobj:
2328 #endif
2329 	xfs_sysfs_del(&xfsstats.xs_kobj);
2330  out_free_stats:
2331 	free_percpu(xfsstats.xs_stats);
2332  out_kset_unregister:
2333 	kset_unregister(xfs_kset);
2334  out_sysctl_unregister:
2335 	xfs_sysctl_unregister();
2336  out_cleanup_procfs:
2337 	xfs_cleanup_procfs();
2338  out_buf_terminate:
2339 	xfs_buf_terminate();
2340  out_mru_cache_uninit:
2341 	xfs_mru_cache_uninit();
2342  out_destroy_wq:
2343 	xfs_destroy_workqueues();
2344  out_destroy_caches:
2345 	xfs_destroy_caches();
2346  out_destroy_hp:
2347 	xfs_cpu_hotplug_destroy();
2348  out:
2349 	return error;
2350 }
2351 
2352 STATIC void __exit
2353 exit_xfs_fs(void)
2354 {
2355 	xfs_qm_exit();
2356 	unregister_filesystem(&xfs_fs_type);
2357 #ifdef DEBUG
2358 	xfs_sysfs_del(&xfs_dbg_kobj);
2359 #endif
2360 	xfs_sysfs_del(&xfsstats.xs_kobj);
2361 	free_percpu(xfsstats.xs_stats);
2362 	kset_unregister(xfs_kset);
2363 	xfs_sysctl_unregister();
2364 	xfs_cleanup_procfs();
2365 	xfs_buf_terminate();
2366 	xfs_mru_cache_uninit();
2367 	xfs_destroy_workqueues();
2368 	xfs_destroy_caches();
2369 	xfs_uuid_table_free();
2370 	xfs_cpu_hotplug_destroy();
2371 }
2372 
2373 module_init(init_xfs_fs);
2374 module_exit(exit_xfs_fs);
2375 
2376 MODULE_AUTHOR("Silicon Graphics, Inc.");
2377 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2378 MODULE_LICENSE("GPL");
2379