xref: /openbmc/linux/fs/xfs/xfs_super.c (revision e330fb14)
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 
41 #include <linux/magic.h>
42 #include <linux/fs_context.h>
43 #include <linux/fs_parser.h>
44 
45 static const struct super_operations xfs_super_operations;
46 
47 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
48 #ifdef DEBUG
49 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
50 #endif
51 
52 #ifdef CONFIG_HOTPLUG_CPU
53 static LIST_HEAD(xfs_mount_list);
54 static DEFINE_SPINLOCK(xfs_mount_list_lock);
55 
56 static inline void xfs_mount_list_add(struct xfs_mount *mp)
57 {
58 	spin_lock(&xfs_mount_list_lock);
59 	list_add(&mp->m_mount_list, &xfs_mount_list);
60 	spin_unlock(&xfs_mount_list_lock);
61 }
62 
63 static inline void xfs_mount_list_del(struct xfs_mount *mp)
64 {
65 	spin_lock(&xfs_mount_list_lock);
66 	list_del(&mp->m_mount_list);
67 	spin_unlock(&xfs_mount_list_lock);
68 }
69 #else /* !CONFIG_HOTPLUG_CPU */
70 static inline void xfs_mount_list_add(struct xfs_mount *mp) {}
71 static inline void xfs_mount_list_del(struct xfs_mount *mp) {}
72 #endif
73 
74 enum xfs_dax_mode {
75 	XFS_DAX_INODE = 0,
76 	XFS_DAX_ALWAYS = 1,
77 	XFS_DAX_NEVER = 2,
78 };
79 
80 static void
81 xfs_mount_set_dax_mode(
82 	struct xfs_mount	*mp,
83 	enum xfs_dax_mode	mode)
84 {
85 	switch (mode) {
86 	case XFS_DAX_INODE:
87 		mp->m_features &= ~(XFS_FEAT_DAX_ALWAYS | XFS_FEAT_DAX_NEVER);
88 		break;
89 	case XFS_DAX_ALWAYS:
90 		mp->m_features |= XFS_FEAT_DAX_ALWAYS;
91 		mp->m_features &= ~XFS_FEAT_DAX_NEVER;
92 		break;
93 	case XFS_DAX_NEVER:
94 		mp->m_features |= XFS_FEAT_DAX_NEVER;
95 		mp->m_features &= ~XFS_FEAT_DAX_ALWAYS;
96 		break;
97 	}
98 }
99 
100 static const struct constant_table dax_param_enums[] = {
101 	{"inode",	XFS_DAX_INODE },
102 	{"always",	XFS_DAX_ALWAYS },
103 	{"never",	XFS_DAX_NEVER },
104 	{}
105 };
106 
107 /*
108  * Table driven mount option parser.
109  */
110 enum {
111 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
112 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
113 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
114 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
115 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
116 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
117 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
118 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
119 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
120 };
121 
122 static const struct fs_parameter_spec xfs_fs_parameters[] = {
123 	fsparam_u32("logbufs",		Opt_logbufs),
124 	fsparam_string("logbsize",	Opt_logbsize),
125 	fsparam_string("logdev",	Opt_logdev),
126 	fsparam_string("rtdev",		Opt_rtdev),
127 	fsparam_flag("wsync",		Opt_wsync),
128 	fsparam_flag("noalign",		Opt_noalign),
129 	fsparam_flag("swalloc",		Opt_swalloc),
130 	fsparam_u32("sunit",		Opt_sunit),
131 	fsparam_u32("swidth",		Opt_swidth),
132 	fsparam_flag("nouuid",		Opt_nouuid),
133 	fsparam_flag("grpid",		Opt_grpid),
134 	fsparam_flag("nogrpid",		Opt_nogrpid),
135 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
136 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
137 	fsparam_string("allocsize",	Opt_allocsize),
138 	fsparam_flag("norecovery",	Opt_norecovery),
139 	fsparam_flag("inode64",		Opt_inode64),
140 	fsparam_flag("inode32",		Opt_inode32),
141 	fsparam_flag("ikeep",		Opt_ikeep),
142 	fsparam_flag("noikeep",		Opt_noikeep),
143 	fsparam_flag("largeio",		Opt_largeio),
144 	fsparam_flag("nolargeio",	Opt_nolargeio),
145 	fsparam_flag("attr2",		Opt_attr2),
146 	fsparam_flag("noattr2",		Opt_noattr2),
147 	fsparam_flag("filestreams",	Opt_filestreams),
148 	fsparam_flag("quota",		Opt_quota),
149 	fsparam_flag("noquota",		Opt_noquota),
150 	fsparam_flag("usrquota",	Opt_usrquota),
151 	fsparam_flag("grpquota",	Opt_grpquota),
152 	fsparam_flag("prjquota",	Opt_prjquota),
153 	fsparam_flag("uquota",		Opt_uquota),
154 	fsparam_flag("gquota",		Opt_gquota),
155 	fsparam_flag("pquota",		Opt_pquota),
156 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
157 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
158 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
159 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
160 	fsparam_flag("discard",		Opt_discard),
161 	fsparam_flag("nodiscard",	Opt_nodiscard),
162 	fsparam_flag("dax",		Opt_dax),
163 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
164 	{}
165 };
166 
167 struct proc_xfs_info {
168 	uint64_t	flag;
169 	char		*str;
170 };
171 
172 static int
173 xfs_fs_show_options(
174 	struct seq_file		*m,
175 	struct dentry		*root)
176 {
177 	static struct proc_xfs_info xfs_info_set[] = {
178 		/* the few simple ones we can get from the mount struct */
179 		{ XFS_FEAT_IKEEP,		",ikeep" },
180 		{ XFS_FEAT_WSYNC,		",wsync" },
181 		{ XFS_FEAT_NOALIGN,		",noalign" },
182 		{ XFS_FEAT_SWALLOC,		",swalloc" },
183 		{ XFS_FEAT_NOUUID,		",nouuid" },
184 		{ XFS_FEAT_NORECOVERY,		",norecovery" },
185 		{ XFS_FEAT_ATTR2,		",attr2" },
186 		{ XFS_FEAT_FILESTREAMS,		",filestreams" },
187 		{ XFS_FEAT_GRPID,		",grpid" },
188 		{ XFS_FEAT_DISCARD,		",discard" },
189 		{ XFS_FEAT_LARGE_IOSIZE,	",largeio" },
190 		{ XFS_FEAT_DAX_ALWAYS,		",dax=always" },
191 		{ XFS_FEAT_DAX_NEVER,		",dax=never" },
192 		{ 0, NULL }
193 	};
194 	struct xfs_mount	*mp = XFS_M(root->d_sb);
195 	struct proc_xfs_info	*xfs_infop;
196 
197 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
198 		if (mp->m_features & xfs_infop->flag)
199 			seq_puts(m, xfs_infop->str);
200 	}
201 
202 	seq_printf(m, ",inode%d", xfs_has_small_inums(mp) ? 32 : 64);
203 
204 	if (xfs_has_allocsize(mp))
205 		seq_printf(m, ",allocsize=%dk",
206 			   (1 << mp->m_allocsize_log) >> 10);
207 
208 	if (mp->m_logbufs > 0)
209 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
210 	if (mp->m_logbsize > 0)
211 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
212 
213 	if (mp->m_logname)
214 		seq_show_option(m, "logdev", mp->m_logname);
215 	if (mp->m_rtname)
216 		seq_show_option(m, "rtdev", mp->m_rtname);
217 
218 	if (mp->m_dalign > 0)
219 		seq_printf(m, ",sunit=%d",
220 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
221 	if (mp->m_swidth > 0)
222 		seq_printf(m, ",swidth=%d",
223 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
224 
225 	if (mp->m_qflags & XFS_UQUOTA_ENFD)
226 		seq_puts(m, ",usrquota");
227 	else if (mp->m_qflags & XFS_UQUOTA_ACCT)
228 		seq_puts(m, ",uqnoenforce");
229 
230 	if (mp->m_qflags & XFS_PQUOTA_ENFD)
231 		seq_puts(m, ",prjquota");
232 	else if (mp->m_qflags & XFS_PQUOTA_ACCT)
233 		seq_puts(m, ",pqnoenforce");
234 
235 	if (mp->m_qflags & XFS_GQUOTA_ENFD)
236 		seq_puts(m, ",grpquota");
237 	else if (mp->m_qflags & XFS_GQUOTA_ACCT)
238 		seq_puts(m, ",gqnoenforce");
239 
240 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
241 		seq_puts(m, ",noquota");
242 
243 	return 0;
244 }
245 
246 /*
247  * Set parameters for inode allocation heuristics, taking into account
248  * filesystem size and inode32/inode64 mount options; i.e. specifically
249  * whether or not XFS_FEAT_SMALL_INUMS is set.
250  *
251  * Inode allocation patterns are altered only if inode32 is requested
252  * (XFS_FEAT_SMALL_INUMS), and the filesystem is sufficiently large.
253  * If altered, XFS_OPSTATE_INODE32 is set as well.
254  *
255  * An agcount independent of that in the mount structure is provided
256  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
257  * to the potentially higher ag count.
258  *
259  * Returns the maximum AG index which may contain inodes.
260  */
261 xfs_agnumber_t
262 xfs_set_inode_alloc(
263 	struct xfs_mount *mp,
264 	xfs_agnumber_t	agcount)
265 {
266 	xfs_agnumber_t	index;
267 	xfs_agnumber_t	maxagi = 0;
268 	xfs_sb_t	*sbp = &mp->m_sb;
269 	xfs_agnumber_t	max_metadata;
270 	xfs_agino_t	agino;
271 	xfs_ino_t	ino;
272 
273 	/*
274 	 * Calculate how much should be reserved for inodes to meet
275 	 * the max inode percentage.  Used only for inode32.
276 	 */
277 	if (M_IGEO(mp)->maxicount) {
278 		uint64_t	icount;
279 
280 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
281 		do_div(icount, 100);
282 		icount += sbp->sb_agblocks - 1;
283 		do_div(icount, sbp->sb_agblocks);
284 		max_metadata = icount;
285 	} else {
286 		max_metadata = agcount;
287 	}
288 
289 	/* Get the last possible inode in the filesystem */
290 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
291 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
292 
293 	/*
294 	 * If user asked for no more than 32-bit inodes, and the fs is
295 	 * sufficiently large, set XFS_OPSTATE_INODE32 if we must alter
296 	 * the allocator to accommodate the request.
297 	 */
298 	if (xfs_has_small_inums(mp) && ino > XFS_MAXINUMBER_32)
299 		set_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
300 	else
301 		clear_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
302 
303 	for (index = 0; index < agcount; index++) {
304 		struct xfs_perag	*pag;
305 
306 		ino = XFS_AGINO_TO_INO(mp, index, agino);
307 
308 		pag = xfs_perag_get(mp, index);
309 
310 		if (xfs_is_inode32(mp)) {
311 			if (ino > XFS_MAXINUMBER_32) {
312 				pag->pagi_inodeok = 0;
313 				pag->pagf_metadata = 0;
314 			} else {
315 				pag->pagi_inodeok = 1;
316 				maxagi++;
317 				if (index < max_metadata)
318 					pag->pagf_metadata = 1;
319 				else
320 					pag->pagf_metadata = 0;
321 			}
322 		} else {
323 			pag->pagi_inodeok = 1;
324 			pag->pagf_metadata = 0;
325 		}
326 
327 		xfs_perag_put(pag);
328 	}
329 
330 	return xfs_is_inode32(mp) ? maxagi : agcount;
331 }
332 
333 static bool
334 xfs_buftarg_is_dax(
335 	struct super_block	*sb,
336 	struct xfs_buftarg	*bt)
337 {
338 	return dax_supported(bt->bt_daxdev, bt->bt_bdev, sb->s_blocksize, 0,
339 			bdev_nr_sectors(bt->bt_bdev));
340 }
341 
342 STATIC int
343 xfs_blkdev_get(
344 	xfs_mount_t		*mp,
345 	const char		*name,
346 	struct block_device	**bdevp)
347 {
348 	int			error = 0;
349 
350 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
351 				    mp);
352 	if (IS_ERR(*bdevp)) {
353 		error = PTR_ERR(*bdevp);
354 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
355 	}
356 
357 	return error;
358 }
359 
360 STATIC void
361 xfs_blkdev_put(
362 	struct block_device	*bdev)
363 {
364 	if (bdev)
365 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
366 }
367 
368 STATIC void
369 xfs_close_devices(
370 	struct xfs_mount	*mp)
371 {
372 	struct dax_device *dax_ddev = mp->m_ddev_targp->bt_daxdev;
373 
374 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
375 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
376 		struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev;
377 
378 		xfs_free_buftarg(mp->m_logdev_targp);
379 		xfs_blkdev_put(logdev);
380 		fs_put_dax(dax_logdev);
381 	}
382 	if (mp->m_rtdev_targp) {
383 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
384 		struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev;
385 
386 		xfs_free_buftarg(mp->m_rtdev_targp);
387 		xfs_blkdev_put(rtdev);
388 		fs_put_dax(dax_rtdev);
389 	}
390 	xfs_free_buftarg(mp->m_ddev_targp);
391 	fs_put_dax(dax_ddev);
392 }
393 
394 /*
395  * The file system configurations are:
396  *	(1) device (partition) with data and internal log
397  *	(2) logical volume with data and log subvolumes.
398  *	(3) logical volume with data, log, and realtime subvolumes.
399  *
400  * We only have to handle opening the log and realtime volumes here if
401  * they are present.  The data subvolume has already been opened by
402  * get_sb_bdev() and is stored in sb->s_bdev.
403  */
404 STATIC int
405 xfs_open_devices(
406 	struct xfs_mount	*mp)
407 {
408 	struct block_device	*ddev = mp->m_super->s_bdev;
409 	struct dax_device	*dax_ddev = fs_dax_get_by_bdev(ddev);
410 	struct dax_device	*dax_logdev = NULL, *dax_rtdev = NULL;
411 	struct block_device	*logdev = NULL, *rtdev = NULL;
412 	int			error;
413 
414 	/*
415 	 * Open real time and log devices - order is important.
416 	 */
417 	if (mp->m_logname) {
418 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
419 		if (error)
420 			goto out;
421 		dax_logdev = fs_dax_get_by_bdev(logdev);
422 	}
423 
424 	if (mp->m_rtname) {
425 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
426 		if (error)
427 			goto out_close_logdev;
428 
429 		if (rtdev == ddev || rtdev == logdev) {
430 			xfs_warn(mp,
431 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
432 			error = -EINVAL;
433 			goto out_close_rtdev;
434 		}
435 		dax_rtdev = fs_dax_get_by_bdev(rtdev);
436 	}
437 
438 	/*
439 	 * Setup xfs_mount buffer target pointers
440 	 */
441 	error = -ENOMEM;
442 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev);
443 	if (!mp->m_ddev_targp)
444 		goto out_close_rtdev;
445 
446 	if (rtdev) {
447 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev);
448 		if (!mp->m_rtdev_targp)
449 			goto out_free_ddev_targ;
450 	}
451 
452 	if (logdev && logdev != ddev) {
453 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev);
454 		if (!mp->m_logdev_targp)
455 			goto out_free_rtdev_targ;
456 	} else {
457 		mp->m_logdev_targp = mp->m_ddev_targp;
458 	}
459 
460 	return 0;
461 
462  out_free_rtdev_targ:
463 	if (mp->m_rtdev_targp)
464 		xfs_free_buftarg(mp->m_rtdev_targp);
465  out_free_ddev_targ:
466 	xfs_free_buftarg(mp->m_ddev_targp);
467  out_close_rtdev:
468 	xfs_blkdev_put(rtdev);
469 	fs_put_dax(dax_rtdev);
470  out_close_logdev:
471 	if (logdev && logdev != ddev) {
472 		xfs_blkdev_put(logdev);
473 		fs_put_dax(dax_logdev);
474 	}
475  out:
476 	fs_put_dax(dax_ddev);
477 	return error;
478 }
479 
480 /*
481  * Setup xfs_mount buffer target pointers based on superblock
482  */
483 STATIC int
484 xfs_setup_devices(
485 	struct xfs_mount	*mp)
486 {
487 	int			error;
488 
489 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
490 	if (error)
491 		return error;
492 
493 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
494 		unsigned int	log_sector_size = BBSIZE;
495 
496 		if (xfs_has_sector(mp))
497 			log_sector_size = mp->m_sb.sb_logsectsize;
498 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
499 					    log_sector_size);
500 		if (error)
501 			return error;
502 	}
503 	if (mp->m_rtdev_targp) {
504 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
505 					    mp->m_sb.sb_sectsize);
506 		if (error)
507 			return error;
508 	}
509 
510 	return 0;
511 }
512 
513 STATIC int
514 xfs_init_mount_workqueues(
515 	struct xfs_mount	*mp)
516 {
517 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
518 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
519 			1, mp->m_super->s_id);
520 	if (!mp->m_buf_workqueue)
521 		goto out;
522 
523 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
524 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
525 			0, mp->m_super->s_id);
526 	if (!mp->m_unwritten_workqueue)
527 		goto out_destroy_buf;
528 
529 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
530 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
531 			0, mp->m_super->s_id);
532 	if (!mp->m_reclaim_workqueue)
533 		goto out_destroy_unwritten;
534 
535 	mp->m_blockgc_wq = alloc_workqueue("xfs-blockgc/%s",
536 			XFS_WQFLAGS(WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM),
537 			0, mp->m_super->s_id);
538 	if (!mp->m_blockgc_wq)
539 		goto out_destroy_reclaim;
540 
541 	mp->m_inodegc_wq = alloc_workqueue("xfs-inodegc/%s",
542 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
543 			1, mp->m_super->s_id);
544 	if (!mp->m_inodegc_wq)
545 		goto out_destroy_blockgc;
546 
547 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
548 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
549 	if (!mp->m_sync_workqueue)
550 		goto out_destroy_inodegc;
551 
552 	return 0;
553 
554 out_destroy_inodegc:
555 	destroy_workqueue(mp->m_inodegc_wq);
556 out_destroy_blockgc:
557 	destroy_workqueue(mp->m_blockgc_wq);
558 out_destroy_reclaim:
559 	destroy_workqueue(mp->m_reclaim_workqueue);
560 out_destroy_unwritten:
561 	destroy_workqueue(mp->m_unwritten_workqueue);
562 out_destroy_buf:
563 	destroy_workqueue(mp->m_buf_workqueue);
564 out:
565 	return -ENOMEM;
566 }
567 
568 STATIC void
569 xfs_destroy_mount_workqueues(
570 	struct xfs_mount	*mp)
571 {
572 	destroy_workqueue(mp->m_sync_workqueue);
573 	destroy_workqueue(mp->m_blockgc_wq);
574 	destroy_workqueue(mp->m_inodegc_wq);
575 	destroy_workqueue(mp->m_reclaim_workqueue);
576 	destroy_workqueue(mp->m_unwritten_workqueue);
577 	destroy_workqueue(mp->m_buf_workqueue);
578 }
579 
580 static void
581 xfs_flush_inodes_worker(
582 	struct work_struct	*work)
583 {
584 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
585 						   m_flush_inodes_work);
586 	struct super_block	*sb = mp->m_super;
587 
588 	if (down_read_trylock(&sb->s_umount)) {
589 		sync_inodes_sb(sb);
590 		up_read(&sb->s_umount);
591 	}
592 }
593 
594 /*
595  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
596  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
597  * for IO to complete so that we effectively throttle multiple callers to the
598  * rate at which IO is completing.
599  */
600 void
601 xfs_flush_inodes(
602 	struct xfs_mount	*mp)
603 {
604 	/*
605 	 * If flush_work() returns true then that means we waited for a flush
606 	 * which was already in progress.  Don't bother running another scan.
607 	 */
608 	if (flush_work(&mp->m_flush_inodes_work))
609 		return;
610 
611 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
612 	flush_work(&mp->m_flush_inodes_work);
613 }
614 
615 /* Catch misguided souls that try to use this interface on XFS */
616 STATIC struct inode *
617 xfs_fs_alloc_inode(
618 	struct super_block	*sb)
619 {
620 	BUG();
621 	return NULL;
622 }
623 
624 /*
625  * Now that the generic code is guaranteed not to be accessing
626  * the linux inode, we can inactivate and reclaim the inode.
627  */
628 STATIC void
629 xfs_fs_destroy_inode(
630 	struct inode		*inode)
631 {
632 	struct xfs_inode	*ip = XFS_I(inode);
633 
634 	trace_xfs_destroy_inode(ip);
635 
636 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
637 	XFS_STATS_INC(ip->i_mount, vn_rele);
638 	XFS_STATS_INC(ip->i_mount, vn_remove);
639 	xfs_inode_mark_reclaimable(ip);
640 }
641 
642 static void
643 xfs_fs_dirty_inode(
644 	struct inode			*inode,
645 	int				flag)
646 {
647 	struct xfs_inode		*ip = XFS_I(inode);
648 	struct xfs_mount		*mp = ip->i_mount;
649 	struct xfs_trans		*tp;
650 
651 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
652 		return;
653 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
654 		return;
655 
656 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
657 		return;
658 	xfs_ilock(ip, XFS_ILOCK_EXCL);
659 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
660 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
661 	xfs_trans_commit(tp);
662 }
663 
664 /*
665  * Slab object creation initialisation for the XFS inode.
666  * This covers only the idempotent fields in the XFS inode;
667  * all other fields need to be initialised on allocation
668  * from the slab. This avoids the need to repeatedly initialise
669  * fields in the xfs inode that left in the initialise state
670  * when freeing the inode.
671  */
672 STATIC void
673 xfs_fs_inode_init_once(
674 	void			*inode)
675 {
676 	struct xfs_inode	*ip = inode;
677 
678 	memset(ip, 0, sizeof(struct xfs_inode));
679 
680 	/* vfs inode */
681 	inode_init_once(VFS_I(ip));
682 
683 	/* xfs inode */
684 	atomic_set(&ip->i_pincount, 0);
685 	spin_lock_init(&ip->i_flags_lock);
686 
687 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
688 		     "xfsino", ip->i_ino);
689 }
690 
691 /*
692  * We do an unlocked check for XFS_IDONTCACHE here because we are already
693  * serialised against cache hits here via the inode->i_lock and igrab() in
694  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
695  * racing with us, and it avoids needing to grab a spinlock here for every inode
696  * we drop the final reference on.
697  */
698 STATIC int
699 xfs_fs_drop_inode(
700 	struct inode		*inode)
701 {
702 	struct xfs_inode	*ip = XFS_I(inode);
703 
704 	/*
705 	 * If this unlinked inode is in the middle of recovery, don't
706 	 * drop the inode just yet; log recovery will take care of
707 	 * that.  See the comment for this inode flag.
708 	 */
709 	if (ip->i_flags & XFS_IRECOVERY) {
710 		ASSERT(xlog_recovery_needed(ip->i_mount->m_log));
711 		return 0;
712 	}
713 
714 	return generic_drop_inode(inode);
715 }
716 
717 static void
718 xfs_mount_free(
719 	struct xfs_mount	*mp)
720 {
721 	kfree(mp->m_rtname);
722 	kfree(mp->m_logname);
723 	kmem_free(mp);
724 }
725 
726 STATIC int
727 xfs_fs_sync_fs(
728 	struct super_block	*sb,
729 	int			wait)
730 {
731 	struct xfs_mount	*mp = XFS_M(sb);
732 
733 	trace_xfs_fs_sync_fs(mp, __return_address);
734 
735 	/*
736 	 * Doing anything during the async pass would be counterproductive.
737 	 */
738 	if (!wait)
739 		return 0;
740 
741 	xfs_log_force(mp, XFS_LOG_SYNC);
742 	if (laptop_mode) {
743 		/*
744 		 * The disk must be active because we're syncing.
745 		 * We schedule log work now (now that the disk is
746 		 * active) instead of later (when it might not be).
747 		 */
748 		flush_delayed_work(&mp->m_log->l_work);
749 	}
750 
751 	/*
752 	 * If we are called with page faults frozen out, it means we are about
753 	 * to freeze the transaction subsystem. Take the opportunity to shut
754 	 * down inodegc because once SB_FREEZE_FS is set it's too late to
755 	 * prevent inactivation races with freeze. The fs doesn't get called
756 	 * again by the freezing process until after SB_FREEZE_FS has been set,
757 	 * so it's now or never.  Same logic applies to speculative allocation
758 	 * garbage collection.
759 	 *
760 	 * We don't care if this is a normal syncfs call that does this or
761 	 * freeze that does this - we can run this multiple times without issue
762 	 * and we won't race with a restart because a restart can only occur
763 	 * when the state is either SB_FREEZE_FS or SB_FREEZE_COMPLETE.
764 	 */
765 	if (sb->s_writers.frozen == SB_FREEZE_PAGEFAULT) {
766 		xfs_inodegc_stop(mp);
767 		xfs_blockgc_stop(mp);
768 	}
769 
770 	return 0;
771 }
772 
773 STATIC int
774 xfs_fs_statfs(
775 	struct dentry		*dentry,
776 	struct kstatfs		*statp)
777 {
778 	struct xfs_mount	*mp = XFS_M(dentry->d_sb);
779 	xfs_sb_t		*sbp = &mp->m_sb;
780 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
781 	uint64_t		fakeinos, id;
782 	uint64_t		icount;
783 	uint64_t		ifree;
784 	uint64_t		fdblocks;
785 	xfs_extlen_t		lsize;
786 	int64_t			ffree;
787 
788 	/* Wait for whatever inactivations are in progress. */
789 	xfs_inodegc_flush(mp);
790 
791 	statp->f_type = XFS_SUPER_MAGIC;
792 	statp->f_namelen = MAXNAMELEN - 1;
793 
794 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
795 	statp->f_fsid = u64_to_fsid(id);
796 
797 	icount = percpu_counter_sum(&mp->m_icount);
798 	ifree = percpu_counter_sum(&mp->m_ifree);
799 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
800 
801 	spin_lock(&mp->m_sb_lock);
802 	statp->f_bsize = sbp->sb_blocksize;
803 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
804 	statp->f_blocks = sbp->sb_dblocks - lsize;
805 	spin_unlock(&mp->m_sb_lock);
806 
807 	/* make sure statp->f_bfree does not underflow */
808 	statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0);
809 	statp->f_bavail = statp->f_bfree;
810 
811 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
812 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
813 	if (M_IGEO(mp)->maxicount)
814 		statp->f_files = min_t(typeof(statp->f_files),
815 					statp->f_files,
816 					M_IGEO(mp)->maxicount);
817 
818 	/* If sb_icount overshot maxicount, report actual allocation */
819 	statp->f_files = max_t(typeof(statp->f_files),
820 					statp->f_files,
821 					sbp->sb_icount);
822 
823 	/* make sure statp->f_ffree does not underflow */
824 	ffree = statp->f_files - (icount - ifree);
825 	statp->f_ffree = max_t(int64_t, ffree, 0);
826 
827 
828 	if ((ip->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
829 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
830 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
831 		xfs_qm_statvfs(ip, statp);
832 
833 	if (XFS_IS_REALTIME_MOUNT(mp) &&
834 	    (ip->i_diflags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
835 		statp->f_blocks = sbp->sb_rblocks;
836 		statp->f_bavail = statp->f_bfree =
837 			sbp->sb_frextents * sbp->sb_rextsize;
838 	}
839 
840 	return 0;
841 }
842 
843 STATIC void
844 xfs_save_resvblks(struct xfs_mount *mp)
845 {
846 	uint64_t resblks = 0;
847 
848 	mp->m_resblks_save = mp->m_resblks;
849 	xfs_reserve_blocks(mp, &resblks, NULL);
850 }
851 
852 STATIC void
853 xfs_restore_resvblks(struct xfs_mount *mp)
854 {
855 	uint64_t resblks;
856 
857 	if (mp->m_resblks_save) {
858 		resblks = mp->m_resblks_save;
859 		mp->m_resblks_save = 0;
860 	} else
861 		resblks = xfs_default_resblks(mp);
862 
863 	xfs_reserve_blocks(mp, &resblks, NULL);
864 }
865 
866 /*
867  * Second stage of a freeze. The data is already frozen so we only
868  * need to take care of the metadata. Once that's done sync the superblock
869  * to the log to dirty it in case of a crash while frozen. This ensures that we
870  * will recover the unlinked inode lists on the next mount.
871  */
872 STATIC int
873 xfs_fs_freeze(
874 	struct super_block	*sb)
875 {
876 	struct xfs_mount	*mp = XFS_M(sb);
877 	unsigned int		flags;
878 	int			ret;
879 
880 	/*
881 	 * The filesystem is now frozen far enough that memory reclaim
882 	 * cannot safely operate on the filesystem. Hence we need to
883 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
884 	 */
885 	flags = memalloc_nofs_save();
886 	xfs_save_resvblks(mp);
887 	ret = xfs_log_quiesce(mp);
888 	memalloc_nofs_restore(flags);
889 
890 	/*
891 	 * For read-write filesystems, we need to restart the inodegc on error
892 	 * because we stopped it at SB_FREEZE_PAGEFAULT level and a thaw is not
893 	 * going to be run to restart it now.  We are at SB_FREEZE_FS level
894 	 * here, so we can restart safely without racing with a stop in
895 	 * xfs_fs_sync_fs().
896 	 */
897 	if (ret && !xfs_is_readonly(mp)) {
898 		xfs_blockgc_start(mp);
899 		xfs_inodegc_start(mp);
900 	}
901 
902 	return ret;
903 }
904 
905 STATIC int
906 xfs_fs_unfreeze(
907 	struct super_block	*sb)
908 {
909 	struct xfs_mount	*mp = XFS_M(sb);
910 
911 	xfs_restore_resvblks(mp);
912 	xfs_log_work_queue(mp);
913 
914 	/*
915 	 * Don't reactivate the inodegc worker on a readonly filesystem because
916 	 * inodes are sent directly to reclaim.  Don't reactivate the blockgc
917 	 * worker because there are no speculative preallocations on a readonly
918 	 * filesystem.
919 	 */
920 	if (!xfs_is_readonly(mp)) {
921 		xfs_blockgc_start(mp);
922 		xfs_inodegc_start(mp);
923 	}
924 
925 	return 0;
926 }
927 
928 /*
929  * This function fills in xfs_mount_t fields based on mount args.
930  * Note: the superblock _has_ now been read in.
931  */
932 STATIC int
933 xfs_finish_flags(
934 	struct xfs_mount	*mp)
935 {
936 	/* Fail a mount where the logbuf is smaller than the log stripe */
937 	if (xfs_has_logv2(mp)) {
938 		if (mp->m_logbsize <= 0 &&
939 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
940 			mp->m_logbsize = mp->m_sb.sb_logsunit;
941 		} else if (mp->m_logbsize > 0 &&
942 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
943 			xfs_warn(mp,
944 		"logbuf size must be greater than or equal to log stripe size");
945 			return -EINVAL;
946 		}
947 	} else {
948 		/* Fail a mount if the logbuf is larger than 32K */
949 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
950 			xfs_warn(mp,
951 		"logbuf size for version 1 logs must be 16K or 32K");
952 			return -EINVAL;
953 		}
954 	}
955 
956 	/*
957 	 * V5 filesystems always use attr2 format for attributes.
958 	 */
959 	if (xfs_has_crc(mp) && xfs_has_noattr2(mp)) {
960 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
961 			     "attr2 is always enabled for V5 filesystems.");
962 		return -EINVAL;
963 	}
964 
965 	/*
966 	 * prohibit r/w mounts of read-only filesystems
967 	 */
968 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !xfs_is_readonly(mp)) {
969 		xfs_warn(mp,
970 			"cannot mount a read-only filesystem as read-write");
971 		return -EROFS;
972 	}
973 
974 	if ((mp->m_qflags & XFS_GQUOTA_ACCT) &&
975 	    (mp->m_qflags & XFS_PQUOTA_ACCT) &&
976 	    !xfs_has_pquotino(mp)) {
977 		xfs_warn(mp,
978 		  "Super block does not support project and group quota together");
979 		return -EINVAL;
980 	}
981 
982 	return 0;
983 }
984 
985 static int
986 xfs_init_percpu_counters(
987 	struct xfs_mount	*mp)
988 {
989 	int		error;
990 
991 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
992 	if (error)
993 		return -ENOMEM;
994 
995 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
996 	if (error)
997 		goto free_icount;
998 
999 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
1000 	if (error)
1001 		goto free_ifree;
1002 
1003 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
1004 	if (error)
1005 		goto free_fdblocks;
1006 
1007 	return 0;
1008 
1009 free_fdblocks:
1010 	percpu_counter_destroy(&mp->m_fdblocks);
1011 free_ifree:
1012 	percpu_counter_destroy(&mp->m_ifree);
1013 free_icount:
1014 	percpu_counter_destroy(&mp->m_icount);
1015 	return -ENOMEM;
1016 }
1017 
1018 void
1019 xfs_reinit_percpu_counters(
1020 	struct xfs_mount	*mp)
1021 {
1022 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1023 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1024 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1025 }
1026 
1027 static void
1028 xfs_destroy_percpu_counters(
1029 	struct xfs_mount	*mp)
1030 {
1031 	percpu_counter_destroy(&mp->m_icount);
1032 	percpu_counter_destroy(&mp->m_ifree);
1033 	percpu_counter_destroy(&mp->m_fdblocks);
1034 	ASSERT(xfs_is_shutdown(mp) ||
1035 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1036 	percpu_counter_destroy(&mp->m_delalloc_blks);
1037 }
1038 
1039 static int
1040 xfs_inodegc_init_percpu(
1041 	struct xfs_mount	*mp)
1042 {
1043 	struct xfs_inodegc	*gc;
1044 	int			cpu;
1045 
1046 	mp->m_inodegc = alloc_percpu(struct xfs_inodegc);
1047 	if (!mp->m_inodegc)
1048 		return -ENOMEM;
1049 
1050 	for_each_possible_cpu(cpu) {
1051 		gc = per_cpu_ptr(mp->m_inodegc, cpu);
1052 		init_llist_head(&gc->list);
1053 		gc->items = 0;
1054 		INIT_WORK(&gc->work, xfs_inodegc_worker);
1055 	}
1056 	return 0;
1057 }
1058 
1059 static void
1060 xfs_inodegc_free_percpu(
1061 	struct xfs_mount	*mp)
1062 {
1063 	if (!mp->m_inodegc)
1064 		return;
1065 	free_percpu(mp->m_inodegc);
1066 }
1067 
1068 static void
1069 xfs_fs_put_super(
1070 	struct super_block	*sb)
1071 {
1072 	struct xfs_mount	*mp = XFS_M(sb);
1073 
1074 	/* if ->fill_super failed, we have no mount to tear down */
1075 	if (!sb->s_fs_info)
1076 		return;
1077 
1078 	xfs_notice(mp, "Unmounting Filesystem");
1079 	xfs_filestream_unmount(mp);
1080 	xfs_unmountfs(mp);
1081 
1082 	xfs_freesb(mp);
1083 	free_percpu(mp->m_stats.xs_stats);
1084 	xfs_mount_list_del(mp);
1085 	xfs_inodegc_free_percpu(mp);
1086 	xfs_destroy_percpu_counters(mp);
1087 	xfs_destroy_mount_workqueues(mp);
1088 	xfs_close_devices(mp);
1089 
1090 	sb->s_fs_info = NULL;
1091 	xfs_mount_free(mp);
1092 }
1093 
1094 static long
1095 xfs_fs_nr_cached_objects(
1096 	struct super_block	*sb,
1097 	struct shrink_control	*sc)
1098 {
1099 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1100 	if (WARN_ON_ONCE(!sb->s_fs_info))
1101 		return 0;
1102 	return xfs_reclaim_inodes_count(XFS_M(sb));
1103 }
1104 
1105 static long
1106 xfs_fs_free_cached_objects(
1107 	struct super_block	*sb,
1108 	struct shrink_control	*sc)
1109 {
1110 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1111 }
1112 
1113 static const struct super_operations xfs_super_operations = {
1114 	.alloc_inode		= xfs_fs_alloc_inode,
1115 	.destroy_inode		= xfs_fs_destroy_inode,
1116 	.dirty_inode		= xfs_fs_dirty_inode,
1117 	.drop_inode		= xfs_fs_drop_inode,
1118 	.put_super		= xfs_fs_put_super,
1119 	.sync_fs		= xfs_fs_sync_fs,
1120 	.freeze_fs		= xfs_fs_freeze,
1121 	.unfreeze_fs		= xfs_fs_unfreeze,
1122 	.statfs			= xfs_fs_statfs,
1123 	.show_options		= xfs_fs_show_options,
1124 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1125 	.free_cached_objects	= xfs_fs_free_cached_objects,
1126 };
1127 
1128 static int
1129 suffix_kstrtoint(
1130 	const char	*s,
1131 	unsigned int	base,
1132 	int		*res)
1133 {
1134 	int		last, shift_left_factor = 0, _res;
1135 	char		*value;
1136 	int		ret = 0;
1137 
1138 	value = kstrdup(s, GFP_KERNEL);
1139 	if (!value)
1140 		return -ENOMEM;
1141 
1142 	last = strlen(value) - 1;
1143 	if (value[last] == 'K' || value[last] == 'k') {
1144 		shift_left_factor = 10;
1145 		value[last] = '\0';
1146 	}
1147 	if (value[last] == 'M' || value[last] == 'm') {
1148 		shift_left_factor = 20;
1149 		value[last] = '\0';
1150 	}
1151 	if (value[last] == 'G' || value[last] == 'g') {
1152 		shift_left_factor = 30;
1153 		value[last] = '\0';
1154 	}
1155 
1156 	if (kstrtoint(value, base, &_res))
1157 		ret = -EINVAL;
1158 	kfree(value);
1159 	*res = _res << shift_left_factor;
1160 	return ret;
1161 }
1162 
1163 static inline void
1164 xfs_fs_warn_deprecated(
1165 	struct fs_context	*fc,
1166 	struct fs_parameter	*param,
1167 	uint64_t		flag,
1168 	bool			value)
1169 {
1170 	/* Don't print the warning if reconfiguring and current mount point
1171 	 * already had the flag set
1172 	 */
1173 	if ((fc->purpose & FS_CONTEXT_FOR_RECONFIGURE) &&
1174             !!(XFS_M(fc->root->d_sb)->m_features & flag) == value)
1175 		return;
1176 	xfs_warn(fc->s_fs_info, "%s mount option is deprecated.", param->key);
1177 }
1178 
1179 /*
1180  * Set mount state from a mount option.
1181  *
1182  * NOTE: mp->m_super is NULL here!
1183  */
1184 static int
1185 xfs_fs_parse_param(
1186 	struct fs_context	*fc,
1187 	struct fs_parameter	*param)
1188 {
1189 	struct xfs_mount	*parsing_mp = fc->s_fs_info;
1190 	struct fs_parse_result	result;
1191 	int			size = 0;
1192 	int			opt;
1193 
1194 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1195 	if (opt < 0)
1196 		return opt;
1197 
1198 	switch (opt) {
1199 	case Opt_logbufs:
1200 		parsing_mp->m_logbufs = result.uint_32;
1201 		return 0;
1202 	case Opt_logbsize:
1203 		if (suffix_kstrtoint(param->string, 10, &parsing_mp->m_logbsize))
1204 			return -EINVAL;
1205 		return 0;
1206 	case Opt_logdev:
1207 		kfree(parsing_mp->m_logname);
1208 		parsing_mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1209 		if (!parsing_mp->m_logname)
1210 			return -ENOMEM;
1211 		return 0;
1212 	case Opt_rtdev:
1213 		kfree(parsing_mp->m_rtname);
1214 		parsing_mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1215 		if (!parsing_mp->m_rtname)
1216 			return -ENOMEM;
1217 		return 0;
1218 	case Opt_allocsize:
1219 		if (suffix_kstrtoint(param->string, 10, &size))
1220 			return -EINVAL;
1221 		parsing_mp->m_allocsize_log = ffs(size) - 1;
1222 		parsing_mp->m_features |= XFS_FEAT_ALLOCSIZE;
1223 		return 0;
1224 	case Opt_grpid:
1225 	case Opt_bsdgroups:
1226 		parsing_mp->m_features |= XFS_FEAT_GRPID;
1227 		return 0;
1228 	case Opt_nogrpid:
1229 	case Opt_sysvgroups:
1230 		parsing_mp->m_features &= ~XFS_FEAT_GRPID;
1231 		return 0;
1232 	case Opt_wsync:
1233 		parsing_mp->m_features |= XFS_FEAT_WSYNC;
1234 		return 0;
1235 	case Opt_norecovery:
1236 		parsing_mp->m_features |= XFS_FEAT_NORECOVERY;
1237 		return 0;
1238 	case Opt_noalign:
1239 		parsing_mp->m_features |= XFS_FEAT_NOALIGN;
1240 		return 0;
1241 	case Opt_swalloc:
1242 		parsing_mp->m_features |= XFS_FEAT_SWALLOC;
1243 		return 0;
1244 	case Opt_sunit:
1245 		parsing_mp->m_dalign = result.uint_32;
1246 		return 0;
1247 	case Opt_swidth:
1248 		parsing_mp->m_swidth = result.uint_32;
1249 		return 0;
1250 	case Opt_inode32:
1251 		parsing_mp->m_features |= XFS_FEAT_SMALL_INUMS;
1252 		return 0;
1253 	case Opt_inode64:
1254 		parsing_mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1255 		return 0;
1256 	case Opt_nouuid:
1257 		parsing_mp->m_features |= XFS_FEAT_NOUUID;
1258 		return 0;
1259 	case Opt_largeio:
1260 		parsing_mp->m_features |= XFS_FEAT_LARGE_IOSIZE;
1261 		return 0;
1262 	case Opt_nolargeio:
1263 		parsing_mp->m_features &= ~XFS_FEAT_LARGE_IOSIZE;
1264 		return 0;
1265 	case Opt_filestreams:
1266 		parsing_mp->m_features |= XFS_FEAT_FILESTREAMS;
1267 		return 0;
1268 	case Opt_noquota:
1269 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1270 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1271 		return 0;
1272 	case Opt_quota:
1273 	case Opt_uquota:
1274 	case Opt_usrquota:
1275 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ENFD);
1276 		return 0;
1277 	case Opt_qnoenforce:
1278 	case Opt_uqnoenforce:
1279 		parsing_mp->m_qflags |= XFS_UQUOTA_ACCT;
1280 		parsing_mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1281 		return 0;
1282 	case Opt_pquota:
1283 	case Opt_prjquota:
1284 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ENFD);
1285 		return 0;
1286 	case Opt_pqnoenforce:
1287 		parsing_mp->m_qflags |= XFS_PQUOTA_ACCT;
1288 		parsing_mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1289 		return 0;
1290 	case Opt_gquota:
1291 	case Opt_grpquota:
1292 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ENFD);
1293 		return 0;
1294 	case Opt_gqnoenforce:
1295 		parsing_mp->m_qflags |= XFS_GQUOTA_ACCT;
1296 		parsing_mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1297 		return 0;
1298 	case Opt_discard:
1299 		parsing_mp->m_features |= XFS_FEAT_DISCARD;
1300 		return 0;
1301 	case Opt_nodiscard:
1302 		parsing_mp->m_features &= ~XFS_FEAT_DISCARD;
1303 		return 0;
1304 #ifdef CONFIG_FS_DAX
1305 	case Opt_dax:
1306 		xfs_mount_set_dax_mode(parsing_mp, XFS_DAX_ALWAYS);
1307 		return 0;
1308 	case Opt_dax_enum:
1309 		xfs_mount_set_dax_mode(parsing_mp, result.uint_32);
1310 		return 0;
1311 #endif
1312 	/* Following mount options will be removed in September 2025 */
1313 	case Opt_ikeep:
1314 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, true);
1315 		parsing_mp->m_features |= XFS_FEAT_IKEEP;
1316 		return 0;
1317 	case Opt_noikeep:
1318 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, false);
1319 		parsing_mp->m_features &= ~XFS_FEAT_IKEEP;
1320 		return 0;
1321 	case Opt_attr2:
1322 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_ATTR2, true);
1323 		parsing_mp->m_features |= XFS_FEAT_ATTR2;
1324 		return 0;
1325 	case Opt_noattr2:
1326 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_NOATTR2, true);
1327 		parsing_mp->m_features |= XFS_FEAT_NOATTR2;
1328 		return 0;
1329 	default:
1330 		xfs_warn(parsing_mp, "unknown mount option [%s].", param->key);
1331 		return -EINVAL;
1332 	}
1333 
1334 	return 0;
1335 }
1336 
1337 static int
1338 xfs_fs_validate_params(
1339 	struct xfs_mount	*mp)
1340 {
1341 	/* No recovery flag requires a read-only mount */
1342 	if (xfs_has_norecovery(mp) && !xfs_is_readonly(mp)) {
1343 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1344 		return -EINVAL;
1345 	}
1346 
1347 	/*
1348 	 * We have not read the superblock at this point, so only the attr2
1349 	 * mount option can set the attr2 feature by this stage.
1350 	 */
1351 	if (xfs_has_attr2(mp) && xfs_has_noattr2(mp)) {
1352 		xfs_warn(mp, "attr2 and noattr2 cannot both be specified.");
1353 		return -EINVAL;
1354 	}
1355 
1356 
1357 	if (xfs_has_noalign(mp) && (mp->m_dalign || mp->m_swidth)) {
1358 		xfs_warn(mp,
1359 	"sunit and swidth options incompatible with the noalign option");
1360 		return -EINVAL;
1361 	}
1362 
1363 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1364 		xfs_warn(mp, "quota support not available in this kernel.");
1365 		return -EINVAL;
1366 	}
1367 
1368 	if ((mp->m_dalign && !mp->m_swidth) ||
1369 	    (!mp->m_dalign && mp->m_swidth)) {
1370 		xfs_warn(mp, "sunit and swidth must be specified together");
1371 		return -EINVAL;
1372 	}
1373 
1374 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1375 		xfs_warn(mp,
1376 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1377 			mp->m_swidth, mp->m_dalign);
1378 		return -EINVAL;
1379 	}
1380 
1381 	if (mp->m_logbufs != -1 &&
1382 	    mp->m_logbufs != 0 &&
1383 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1384 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1385 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1386 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1387 		return -EINVAL;
1388 	}
1389 
1390 	if (mp->m_logbsize != -1 &&
1391 	    mp->m_logbsize !=  0 &&
1392 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1393 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1394 	     !is_power_of_2(mp->m_logbsize))) {
1395 		xfs_warn(mp,
1396 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1397 			mp->m_logbsize);
1398 		return -EINVAL;
1399 	}
1400 
1401 	if (xfs_has_allocsize(mp) &&
1402 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1403 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1404 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1405 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1406 		return -EINVAL;
1407 	}
1408 
1409 	return 0;
1410 }
1411 
1412 static int
1413 xfs_fs_fill_super(
1414 	struct super_block	*sb,
1415 	struct fs_context	*fc)
1416 {
1417 	struct xfs_mount	*mp = sb->s_fs_info;
1418 	struct inode		*root;
1419 	int			flags = 0, error;
1420 
1421 	mp->m_super = sb;
1422 
1423 	error = xfs_fs_validate_params(mp);
1424 	if (error)
1425 		goto out_free_names;
1426 
1427 	sb_min_blocksize(sb, BBSIZE);
1428 	sb->s_xattr = xfs_xattr_handlers;
1429 	sb->s_export_op = &xfs_export_operations;
1430 #ifdef CONFIG_XFS_QUOTA
1431 	sb->s_qcop = &xfs_quotactl_operations;
1432 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1433 #endif
1434 	sb->s_op = &xfs_super_operations;
1435 
1436 	/*
1437 	 * Delay mount work if the debug hook is set. This is debug
1438 	 * instrumention to coordinate simulation of xfs mount failures with
1439 	 * VFS superblock operations
1440 	 */
1441 	if (xfs_globals.mount_delay) {
1442 		xfs_notice(mp, "Delaying mount for %d seconds.",
1443 			xfs_globals.mount_delay);
1444 		msleep(xfs_globals.mount_delay * 1000);
1445 	}
1446 
1447 	if (fc->sb_flags & SB_SILENT)
1448 		flags |= XFS_MFSI_QUIET;
1449 
1450 	error = xfs_open_devices(mp);
1451 	if (error)
1452 		goto out_free_names;
1453 
1454 	error = xfs_init_mount_workqueues(mp);
1455 	if (error)
1456 		goto out_close_devices;
1457 
1458 	error = xfs_init_percpu_counters(mp);
1459 	if (error)
1460 		goto out_destroy_workqueues;
1461 
1462 	error = xfs_inodegc_init_percpu(mp);
1463 	if (error)
1464 		goto out_destroy_counters;
1465 
1466 	/*
1467 	 * All percpu data structures requiring cleanup when a cpu goes offline
1468 	 * must be allocated before adding this @mp to the cpu-dead handler's
1469 	 * mount list.
1470 	 */
1471 	xfs_mount_list_add(mp);
1472 
1473 	/* Allocate stats memory before we do operations that might use it */
1474 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1475 	if (!mp->m_stats.xs_stats) {
1476 		error = -ENOMEM;
1477 		goto out_destroy_inodegc;
1478 	}
1479 
1480 	error = xfs_readsb(mp, flags);
1481 	if (error)
1482 		goto out_free_stats;
1483 
1484 	error = xfs_finish_flags(mp);
1485 	if (error)
1486 		goto out_free_sb;
1487 
1488 	error = xfs_setup_devices(mp);
1489 	if (error)
1490 		goto out_free_sb;
1491 
1492 	/* V4 support is undergoing deprecation. */
1493 	if (!xfs_has_crc(mp)) {
1494 #ifdef CONFIG_XFS_SUPPORT_V4
1495 		xfs_warn_once(mp,
1496 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1497 #else
1498 		xfs_warn(mp,
1499 	"Deprecated V4 format (crc=0) not supported by kernel.");
1500 		error = -EINVAL;
1501 		goto out_free_sb;
1502 #endif
1503 	}
1504 
1505 	/* Filesystem claims it needs repair, so refuse the mount. */
1506 	if (xfs_has_needsrepair(mp)) {
1507 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1508 		error = -EFSCORRUPTED;
1509 		goto out_free_sb;
1510 	}
1511 
1512 	/*
1513 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1514 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1515 	 * we don't check them at all.
1516 	 */
1517 	if (mp->m_sb.sb_inprogress) {
1518 		xfs_warn(mp, "Offline file system operation in progress!");
1519 		error = -EFSCORRUPTED;
1520 		goto out_free_sb;
1521 	}
1522 
1523 	/*
1524 	 * Until this is fixed only page-sized or smaller data blocks work.
1525 	 */
1526 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1527 		xfs_warn(mp,
1528 		"File system with blocksize %d bytes. "
1529 		"Only pagesize (%ld) or less will currently work.",
1530 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1531 		error = -ENOSYS;
1532 		goto out_free_sb;
1533 	}
1534 
1535 	/* Ensure this filesystem fits in the page cache limits */
1536 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1537 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1538 		xfs_warn(mp,
1539 		"file system too large to be mounted on this system.");
1540 		error = -EFBIG;
1541 		goto out_free_sb;
1542 	}
1543 
1544 	/*
1545 	 * XFS block mappings use 54 bits to store the logical block offset.
1546 	 * This should suffice to handle the maximum file size that the VFS
1547 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1548 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1549 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1550 	 * to check this assertion.
1551 	 *
1552 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1553 	 * maximum pagecache offset in units of fs blocks.
1554 	 */
1555 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1556 		xfs_warn(mp,
1557 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1558 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1559 			 XFS_MAX_FILEOFF);
1560 		error = -EINVAL;
1561 		goto out_free_sb;
1562 	}
1563 
1564 	error = xfs_filestream_mount(mp);
1565 	if (error)
1566 		goto out_free_sb;
1567 
1568 	/*
1569 	 * we must configure the block size in the superblock before we run the
1570 	 * full mount process as the mount process can lookup and cache inodes.
1571 	 */
1572 	sb->s_magic = XFS_SUPER_MAGIC;
1573 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1574 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1575 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1576 	sb->s_max_links = XFS_MAXLINK;
1577 	sb->s_time_gran = 1;
1578 	if (xfs_has_bigtime(mp)) {
1579 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1580 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1581 	} else {
1582 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1583 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1584 	}
1585 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1586 	sb->s_iflags |= SB_I_CGROUPWB;
1587 
1588 	set_posix_acl_flag(sb);
1589 
1590 	/* version 5 superblocks support inode version counters. */
1591 	if (xfs_has_crc(mp))
1592 		sb->s_flags |= SB_I_VERSION;
1593 
1594 	if (xfs_has_dax_always(mp)) {
1595 		bool rtdev_is_dax = false, datadev_is_dax;
1596 
1597 		xfs_warn(mp,
1598 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1599 
1600 		datadev_is_dax = xfs_buftarg_is_dax(sb, mp->m_ddev_targp);
1601 		if (mp->m_rtdev_targp)
1602 			rtdev_is_dax = xfs_buftarg_is_dax(sb,
1603 						mp->m_rtdev_targp);
1604 		if (!rtdev_is_dax && !datadev_is_dax) {
1605 			xfs_alert(mp,
1606 			"DAX unsupported by block device. Turning off DAX.");
1607 			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
1608 		}
1609 		if (xfs_has_reflink(mp)) {
1610 			xfs_alert(mp,
1611 		"DAX and reflink cannot be used together!");
1612 			error = -EINVAL;
1613 			goto out_filestream_unmount;
1614 		}
1615 	}
1616 
1617 	if (xfs_has_discard(mp)) {
1618 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1619 
1620 		if (!blk_queue_discard(q)) {
1621 			xfs_warn(mp, "mounting with \"discard\" option, but "
1622 					"the device does not support discard");
1623 			mp->m_features &= ~XFS_FEAT_DISCARD;
1624 		}
1625 	}
1626 
1627 	if (xfs_has_reflink(mp)) {
1628 		if (mp->m_sb.sb_rblocks) {
1629 			xfs_alert(mp,
1630 	"reflink not compatible with realtime device!");
1631 			error = -EINVAL;
1632 			goto out_filestream_unmount;
1633 		}
1634 
1635 		if (xfs_globals.always_cow) {
1636 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1637 			mp->m_always_cow = true;
1638 		}
1639 	}
1640 
1641 	if (xfs_has_rmapbt(mp) && mp->m_sb.sb_rblocks) {
1642 		xfs_alert(mp,
1643 	"reverse mapping btree not compatible with realtime device!");
1644 		error = -EINVAL;
1645 		goto out_filestream_unmount;
1646 	}
1647 
1648 	error = xfs_mountfs(mp);
1649 	if (error)
1650 		goto out_filestream_unmount;
1651 
1652 	root = igrab(VFS_I(mp->m_rootip));
1653 	if (!root) {
1654 		error = -ENOENT;
1655 		goto out_unmount;
1656 	}
1657 	sb->s_root = d_make_root(root);
1658 	if (!sb->s_root) {
1659 		error = -ENOMEM;
1660 		goto out_unmount;
1661 	}
1662 
1663 	return 0;
1664 
1665  out_filestream_unmount:
1666 	xfs_filestream_unmount(mp);
1667  out_free_sb:
1668 	xfs_freesb(mp);
1669  out_free_stats:
1670 	free_percpu(mp->m_stats.xs_stats);
1671  out_destroy_inodegc:
1672 	xfs_mount_list_del(mp);
1673 	xfs_inodegc_free_percpu(mp);
1674  out_destroy_counters:
1675 	xfs_destroy_percpu_counters(mp);
1676  out_destroy_workqueues:
1677 	xfs_destroy_mount_workqueues(mp);
1678  out_close_devices:
1679 	xfs_close_devices(mp);
1680  out_free_names:
1681 	sb->s_fs_info = NULL;
1682 	xfs_mount_free(mp);
1683 	return error;
1684 
1685  out_unmount:
1686 	xfs_filestream_unmount(mp);
1687 	xfs_unmountfs(mp);
1688 	goto out_free_sb;
1689 }
1690 
1691 static int
1692 xfs_fs_get_tree(
1693 	struct fs_context	*fc)
1694 {
1695 	return get_tree_bdev(fc, xfs_fs_fill_super);
1696 }
1697 
1698 static int
1699 xfs_remount_rw(
1700 	struct xfs_mount	*mp)
1701 {
1702 	struct xfs_sb		*sbp = &mp->m_sb;
1703 	int error;
1704 
1705 	if (xfs_has_norecovery(mp)) {
1706 		xfs_warn(mp,
1707 			"ro->rw transition prohibited on norecovery mount");
1708 		return -EINVAL;
1709 	}
1710 
1711 	if (xfs_sb_is_v5(sbp) &&
1712 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1713 		xfs_warn(mp,
1714 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1715 			(sbp->sb_features_ro_compat &
1716 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1717 		return -EINVAL;
1718 	}
1719 
1720 	clear_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1721 
1722 	/*
1723 	 * If this is the first remount to writeable state we might have some
1724 	 * superblock changes to update.
1725 	 */
1726 	if (mp->m_update_sb) {
1727 		error = xfs_sync_sb(mp, false);
1728 		if (error) {
1729 			xfs_warn(mp, "failed to write sb changes");
1730 			return error;
1731 		}
1732 		mp->m_update_sb = false;
1733 	}
1734 
1735 	/*
1736 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1737 	 * it is non-zero, otherwise go with the default.
1738 	 */
1739 	xfs_restore_resvblks(mp);
1740 	xfs_log_work_queue(mp);
1741 
1742 	/* Recover any CoW blocks that never got remapped. */
1743 	error = xfs_reflink_recover_cow(mp);
1744 	if (error) {
1745 		xfs_err(mp,
1746 			"Error %d recovering leftover CoW allocations.", error);
1747 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1748 		return error;
1749 	}
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 	int error;
1768 
1769 	/*
1770 	 * Cancel background eofb scanning so it cannot race with the final
1771 	 * log force+buftarg wait and deadlock the remount.
1772 	 */
1773 	xfs_blockgc_stop(mp);
1774 
1775 	/* Get rid of any leftover CoW reservations... */
1776 	error = xfs_blockgc_free_space(mp, NULL);
1777 	if (error) {
1778 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1779 		return error;
1780 	}
1781 
1782 	/*
1783 	 * Stop the inodegc background worker.  xfs_fs_reconfigure already
1784 	 * flushed all pending inodegc work when it sync'd the filesystem.
1785 	 * The VFS holds s_umount, so we know that inodes cannot enter
1786 	 * xfs_fs_destroy_inode during a remount operation.  In readonly mode
1787 	 * we send inodes straight to reclaim, so no inodes will be queued.
1788 	 */
1789 	xfs_inodegc_stop(mp);
1790 
1791 	/* Free the per-AG metadata reservation pool. */
1792 	error = xfs_fs_unreserve_ag_blocks(mp);
1793 	if (error) {
1794 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1795 		return error;
1796 	}
1797 
1798 	/*
1799 	 * Before we sync the metadata, we need to free up the reserve block
1800 	 * pool so that the used block count in the superblock on disk is
1801 	 * correct at the end of the remount. Stash the current* reserve pool
1802 	 * size so that if we get remounted rw, we can return it to the same
1803 	 * size.
1804 	 */
1805 	xfs_save_resvblks(mp);
1806 
1807 	xfs_log_clean(mp);
1808 	set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1809 
1810 	return 0;
1811 }
1812 
1813 /*
1814  * Logically we would return an error here to prevent users from believing
1815  * they might have changed mount options using remount which can't be changed.
1816  *
1817  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1818  * arguments in some cases so we can't blindly reject options, but have to
1819  * check for each specified option if it actually differs from the currently
1820  * set option and only reject it if that's the case.
1821  *
1822  * Until that is implemented we return success for every remount request, and
1823  * silently ignore all options that we can't actually change.
1824  */
1825 static int
1826 xfs_fs_reconfigure(
1827 	struct fs_context *fc)
1828 {
1829 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1830 	struct xfs_mount        *new_mp = fc->s_fs_info;
1831 	int			flags = fc->sb_flags;
1832 	int			error;
1833 
1834 	/* version 5 superblocks always support version counters. */
1835 	if (xfs_has_crc(mp))
1836 		fc->sb_flags |= SB_I_VERSION;
1837 
1838 	error = xfs_fs_validate_params(new_mp);
1839 	if (error)
1840 		return error;
1841 
1842 	sync_filesystem(mp->m_super);
1843 
1844 	/* inode32 -> inode64 */
1845 	if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
1846 		mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1847 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1848 	}
1849 
1850 	/* inode64 -> inode32 */
1851 	if (!xfs_has_small_inums(mp) && xfs_has_small_inums(new_mp)) {
1852 		mp->m_features |= XFS_FEAT_SMALL_INUMS;
1853 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1854 	}
1855 
1856 	/* ro -> rw */
1857 	if (xfs_is_readonly(mp) && !(flags & SB_RDONLY)) {
1858 		error = xfs_remount_rw(mp);
1859 		if (error)
1860 			return error;
1861 	}
1862 
1863 	/* rw -> ro */
1864 	if (!xfs_is_readonly(mp) && (flags & SB_RDONLY)) {
1865 		error = xfs_remount_ro(mp);
1866 		if (error)
1867 			return error;
1868 	}
1869 
1870 	return 0;
1871 }
1872 
1873 static void xfs_fs_free(
1874 	struct fs_context	*fc)
1875 {
1876 	struct xfs_mount	*mp = fc->s_fs_info;
1877 
1878 	/*
1879 	 * mp is stored in the fs_context when it is initialized.
1880 	 * mp is transferred to the superblock on a successful mount,
1881 	 * but if an error occurs before the transfer we have to free
1882 	 * it here.
1883 	 */
1884 	if (mp)
1885 		xfs_mount_free(mp);
1886 }
1887 
1888 static const struct fs_context_operations xfs_context_ops = {
1889 	.parse_param = xfs_fs_parse_param,
1890 	.get_tree    = xfs_fs_get_tree,
1891 	.reconfigure = xfs_fs_reconfigure,
1892 	.free        = xfs_fs_free,
1893 };
1894 
1895 static int xfs_init_fs_context(
1896 	struct fs_context	*fc)
1897 {
1898 	struct xfs_mount	*mp;
1899 
1900 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1901 	if (!mp)
1902 		return -ENOMEM;
1903 
1904 	spin_lock_init(&mp->m_sb_lock);
1905 	spin_lock_init(&mp->m_agirotor_lock);
1906 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1907 	spin_lock_init(&mp->m_perag_lock);
1908 	mutex_init(&mp->m_growlock);
1909 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1910 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1911 	mp->m_kobj.kobject.kset = xfs_kset;
1912 	/*
1913 	 * We don't create the finobt per-ag space reservation until after log
1914 	 * recovery, so we must set this to true so that an ifree transaction
1915 	 * started during log recovery will not depend on space reservations
1916 	 * for finobt expansion.
1917 	 */
1918 	mp->m_finobt_nores = true;
1919 
1920 	/*
1921 	 * These can be overridden by the mount option parsing.
1922 	 */
1923 	mp->m_logbufs = -1;
1924 	mp->m_logbsize = -1;
1925 	mp->m_allocsize_log = 16; /* 64k */
1926 
1927 	/*
1928 	 * Copy binary VFS mount flags we are interested in.
1929 	 */
1930 	if (fc->sb_flags & SB_RDONLY)
1931 		set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1932 	if (fc->sb_flags & SB_DIRSYNC)
1933 		mp->m_features |= XFS_FEAT_DIRSYNC;
1934 	if (fc->sb_flags & SB_SYNCHRONOUS)
1935 		mp->m_features |= XFS_FEAT_WSYNC;
1936 
1937 	fc->s_fs_info = mp;
1938 	fc->ops = &xfs_context_ops;
1939 
1940 	return 0;
1941 }
1942 
1943 static struct file_system_type xfs_fs_type = {
1944 	.owner			= THIS_MODULE,
1945 	.name			= "xfs",
1946 	.init_fs_context	= xfs_init_fs_context,
1947 	.parameters		= xfs_fs_parameters,
1948 	.kill_sb		= kill_block_super,
1949 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1950 };
1951 MODULE_ALIAS_FS("xfs");
1952 
1953 STATIC int __init
1954 xfs_init_zones(void)
1955 {
1956 	xfs_log_ticket_zone = kmem_cache_create("xfs_log_ticket",
1957 						sizeof(struct xlog_ticket),
1958 						0, 0, NULL);
1959 	if (!xfs_log_ticket_zone)
1960 		goto out;
1961 
1962 	xfs_bmap_free_item_zone = kmem_cache_create("xfs_bmap_free_item",
1963 					sizeof(struct xfs_extent_free_item),
1964 					0, 0, NULL);
1965 	if (!xfs_bmap_free_item_zone)
1966 		goto out_destroy_log_ticket_zone;
1967 
1968 	xfs_btree_cur_zone = kmem_cache_create("xfs_btree_cur",
1969 					       sizeof(struct xfs_btree_cur),
1970 					       0, 0, NULL);
1971 	if (!xfs_btree_cur_zone)
1972 		goto out_destroy_bmap_free_item_zone;
1973 
1974 	xfs_da_state_zone = kmem_cache_create("xfs_da_state",
1975 					      sizeof(struct xfs_da_state),
1976 					      0, 0, NULL);
1977 	if (!xfs_da_state_zone)
1978 		goto out_destroy_btree_cur_zone;
1979 
1980 	xfs_ifork_zone = kmem_cache_create("xfs_ifork",
1981 					   sizeof(struct xfs_ifork),
1982 					   0, 0, NULL);
1983 	if (!xfs_ifork_zone)
1984 		goto out_destroy_da_state_zone;
1985 
1986 	xfs_trans_zone = kmem_cache_create("xfs_trans",
1987 					   sizeof(struct xfs_trans),
1988 					   0, 0, NULL);
1989 	if (!xfs_trans_zone)
1990 		goto out_destroy_ifork_zone;
1991 
1992 
1993 	/*
1994 	 * The size of the zone allocated buf log item is the maximum
1995 	 * size possible under XFS.  This wastes a little bit of memory,
1996 	 * but it is much faster.
1997 	 */
1998 	xfs_buf_item_zone = kmem_cache_create("xfs_buf_item",
1999 					      sizeof(struct xfs_buf_log_item),
2000 					      0, 0, NULL);
2001 	if (!xfs_buf_item_zone)
2002 		goto out_destroy_trans_zone;
2003 
2004 	xfs_efd_zone = kmem_cache_create("xfs_efd_item",
2005 					(sizeof(struct xfs_efd_log_item) +
2006 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
2007 					sizeof(struct xfs_extent)),
2008 					0, 0, NULL);
2009 	if (!xfs_efd_zone)
2010 		goto out_destroy_buf_item_zone;
2011 
2012 	xfs_efi_zone = kmem_cache_create("xfs_efi_item",
2013 					 (sizeof(struct xfs_efi_log_item) +
2014 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
2015 					 sizeof(struct xfs_extent)),
2016 					 0, 0, NULL);
2017 	if (!xfs_efi_zone)
2018 		goto out_destroy_efd_zone;
2019 
2020 	xfs_inode_zone = kmem_cache_create("xfs_inode",
2021 					   sizeof(struct xfs_inode), 0,
2022 					   (SLAB_HWCACHE_ALIGN |
2023 					    SLAB_RECLAIM_ACCOUNT |
2024 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
2025 					   xfs_fs_inode_init_once);
2026 	if (!xfs_inode_zone)
2027 		goto out_destroy_efi_zone;
2028 
2029 	xfs_ili_zone = kmem_cache_create("xfs_ili",
2030 					 sizeof(struct xfs_inode_log_item), 0,
2031 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
2032 					 NULL);
2033 	if (!xfs_ili_zone)
2034 		goto out_destroy_inode_zone;
2035 
2036 	xfs_icreate_zone = kmem_cache_create("xfs_icr",
2037 					     sizeof(struct xfs_icreate_item),
2038 					     0, 0, NULL);
2039 	if (!xfs_icreate_zone)
2040 		goto out_destroy_ili_zone;
2041 
2042 	xfs_rud_zone = kmem_cache_create("xfs_rud_item",
2043 					 sizeof(struct xfs_rud_log_item),
2044 					 0, 0, NULL);
2045 	if (!xfs_rud_zone)
2046 		goto out_destroy_icreate_zone;
2047 
2048 	xfs_rui_zone = kmem_cache_create("xfs_rui_item",
2049 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
2050 			0, 0, NULL);
2051 	if (!xfs_rui_zone)
2052 		goto out_destroy_rud_zone;
2053 
2054 	xfs_cud_zone = kmem_cache_create("xfs_cud_item",
2055 					 sizeof(struct xfs_cud_log_item),
2056 					 0, 0, NULL);
2057 	if (!xfs_cud_zone)
2058 		goto out_destroy_rui_zone;
2059 
2060 	xfs_cui_zone = kmem_cache_create("xfs_cui_item",
2061 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2062 			0, 0, NULL);
2063 	if (!xfs_cui_zone)
2064 		goto out_destroy_cud_zone;
2065 
2066 	xfs_bud_zone = kmem_cache_create("xfs_bud_item",
2067 					 sizeof(struct xfs_bud_log_item),
2068 					 0, 0, NULL);
2069 	if (!xfs_bud_zone)
2070 		goto out_destroy_cui_zone;
2071 
2072 	xfs_bui_zone = kmem_cache_create("xfs_bui_item",
2073 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2074 			0, 0, NULL);
2075 	if (!xfs_bui_zone)
2076 		goto out_destroy_bud_zone;
2077 
2078 	return 0;
2079 
2080  out_destroy_bud_zone:
2081 	kmem_cache_destroy(xfs_bud_zone);
2082  out_destroy_cui_zone:
2083 	kmem_cache_destroy(xfs_cui_zone);
2084  out_destroy_cud_zone:
2085 	kmem_cache_destroy(xfs_cud_zone);
2086  out_destroy_rui_zone:
2087 	kmem_cache_destroy(xfs_rui_zone);
2088  out_destroy_rud_zone:
2089 	kmem_cache_destroy(xfs_rud_zone);
2090  out_destroy_icreate_zone:
2091 	kmem_cache_destroy(xfs_icreate_zone);
2092  out_destroy_ili_zone:
2093 	kmem_cache_destroy(xfs_ili_zone);
2094  out_destroy_inode_zone:
2095 	kmem_cache_destroy(xfs_inode_zone);
2096  out_destroy_efi_zone:
2097 	kmem_cache_destroy(xfs_efi_zone);
2098  out_destroy_efd_zone:
2099 	kmem_cache_destroy(xfs_efd_zone);
2100  out_destroy_buf_item_zone:
2101 	kmem_cache_destroy(xfs_buf_item_zone);
2102  out_destroy_trans_zone:
2103 	kmem_cache_destroy(xfs_trans_zone);
2104  out_destroy_ifork_zone:
2105 	kmem_cache_destroy(xfs_ifork_zone);
2106  out_destroy_da_state_zone:
2107 	kmem_cache_destroy(xfs_da_state_zone);
2108  out_destroy_btree_cur_zone:
2109 	kmem_cache_destroy(xfs_btree_cur_zone);
2110  out_destroy_bmap_free_item_zone:
2111 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2112  out_destroy_log_ticket_zone:
2113 	kmem_cache_destroy(xfs_log_ticket_zone);
2114  out:
2115 	return -ENOMEM;
2116 }
2117 
2118 STATIC void
2119 xfs_destroy_zones(void)
2120 {
2121 	/*
2122 	 * Make sure all delayed rcu free are flushed before we
2123 	 * destroy caches.
2124 	 */
2125 	rcu_barrier();
2126 	kmem_cache_destroy(xfs_bui_zone);
2127 	kmem_cache_destroy(xfs_bud_zone);
2128 	kmem_cache_destroy(xfs_cui_zone);
2129 	kmem_cache_destroy(xfs_cud_zone);
2130 	kmem_cache_destroy(xfs_rui_zone);
2131 	kmem_cache_destroy(xfs_rud_zone);
2132 	kmem_cache_destroy(xfs_icreate_zone);
2133 	kmem_cache_destroy(xfs_ili_zone);
2134 	kmem_cache_destroy(xfs_inode_zone);
2135 	kmem_cache_destroy(xfs_efi_zone);
2136 	kmem_cache_destroy(xfs_efd_zone);
2137 	kmem_cache_destroy(xfs_buf_item_zone);
2138 	kmem_cache_destroy(xfs_trans_zone);
2139 	kmem_cache_destroy(xfs_ifork_zone);
2140 	kmem_cache_destroy(xfs_da_state_zone);
2141 	kmem_cache_destroy(xfs_btree_cur_zone);
2142 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2143 	kmem_cache_destroy(xfs_log_ticket_zone);
2144 }
2145 
2146 STATIC int __init
2147 xfs_init_workqueues(void)
2148 {
2149 	/*
2150 	 * The allocation workqueue can be used in memory reclaim situations
2151 	 * (writepage path), and parallelism is only limited by the number of
2152 	 * AGs in all the filesystems mounted. Hence use the default large
2153 	 * max_active value for this workqueue.
2154 	 */
2155 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2156 			XFS_WQFLAGS(WQ_MEM_RECLAIM | WQ_FREEZABLE), 0);
2157 	if (!xfs_alloc_wq)
2158 		return -ENOMEM;
2159 
2160 	xfs_discard_wq = alloc_workqueue("xfsdiscard", XFS_WQFLAGS(WQ_UNBOUND),
2161 			0);
2162 	if (!xfs_discard_wq)
2163 		goto out_free_alloc_wq;
2164 
2165 	return 0;
2166 out_free_alloc_wq:
2167 	destroy_workqueue(xfs_alloc_wq);
2168 	return -ENOMEM;
2169 }
2170 
2171 STATIC void
2172 xfs_destroy_workqueues(void)
2173 {
2174 	destroy_workqueue(xfs_discard_wq);
2175 	destroy_workqueue(xfs_alloc_wq);
2176 }
2177 
2178 #ifdef CONFIG_HOTPLUG_CPU
2179 static int
2180 xfs_cpu_dead(
2181 	unsigned int		cpu)
2182 {
2183 	struct xfs_mount	*mp, *n;
2184 
2185 	spin_lock(&xfs_mount_list_lock);
2186 	list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
2187 		spin_unlock(&xfs_mount_list_lock);
2188 		xfs_inodegc_cpu_dead(mp, cpu);
2189 		spin_lock(&xfs_mount_list_lock);
2190 	}
2191 	spin_unlock(&xfs_mount_list_lock);
2192 	return 0;
2193 }
2194 
2195 static int __init
2196 xfs_cpu_hotplug_init(void)
2197 {
2198 	int	error;
2199 
2200 	error = cpuhp_setup_state_nocalls(CPUHP_XFS_DEAD, "xfs:dead", NULL,
2201 			xfs_cpu_dead);
2202 	if (error < 0)
2203 		xfs_alert(NULL,
2204 "Failed to initialise CPU hotplug, error %d. XFS is non-functional.",
2205 			error);
2206 	return error;
2207 }
2208 
2209 static void
2210 xfs_cpu_hotplug_destroy(void)
2211 {
2212 	cpuhp_remove_state_nocalls(CPUHP_XFS_DEAD);
2213 }
2214 
2215 #else /* !CONFIG_HOTPLUG_CPU */
2216 static inline int xfs_cpu_hotplug_init(void) { return 0; }
2217 static inline void xfs_cpu_hotplug_destroy(void) {}
2218 #endif
2219 
2220 STATIC int __init
2221 init_xfs_fs(void)
2222 {
2223 	int			error;
2224 
2225 	xfs_check_ondisk_structs();
2226 
2227 	printk(KERN_INFO XFS_VERSION_STRING " with "
2228 			 XFS_BUILD_OPTIONS " enabled\n");
2229 
2230 	xfs_dir_startup();
2231 
2232 	error = xfs_cpu_hotplug_init();
2233 	if (error)
2234 		goto out;
2235 
2236 	error = xfs_init_zones();
2237 	if (error)
2238 		goto out_destroy_hp;
2239 
2240 	error = xfs_init_workqueues();
2241 	if (error)
2242 		goto out_destroy_zones;
2243 
2244 	error = xfs_mru_cache_init();
2245 	if (error)
2246 		goto out_destroy_wq;
2247 
2248 	error = xfs_buf_init();
2249 	if (error)
2250 		goto out_mru_cache_uninit;
2251 
2252 	error = xfs_init_procfs();
2253 	if (error)
2254 		goto out_buf_terminate;
2255 
2256 	error = xfs_sysctl_register();
2257 	if (error)
2258 		goto out_cleanup_procfs;
2259 
2260 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2261 	if (!xfs_kset) {
2262 		error = -ENOMEM;
2263 		goto out_sysctl_unregister;
2264 	}
2265 
2266 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2267 
2268 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2269 	if (!xfsstats.xs_stats) {
2270 		error = -ENOMEM;
2271 		goto out_kset_unregister;
2272 	}
2273 
2274 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2275 			       "stats");
2276 	if (error)
2277 		goto out_free_stats;
2278 
2279 #ifdef DEBUG
2280 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2281 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2282 	if (error)
2283 		goto out_remove_stats_kobj;
2284 #endif
2285 
2286 	error = xfs_qm_init();
2287 	if (error)
2288 		goto out_remove_dbg_kobj;
2289 
2290 	error = register_filesystem(&xfs_fs_type);
2291 	if (error)
2292 		goto out_qm_exit;
2293 	return 0;
2294 
2295  out_qm_exit:
2296 	xfs_qm_exit();
2297  out_remove_dbg_kobj:
2298 #ifdef DEBUG
2299 	xfs_sysfs_del(&xfs_dbg_kobj);
2300  out_remove_stats_kobj:
2301 #endif
2302 	xfs_sysfs_del(&xfsstats.xs_kobj);
2303  out_free_stats:
2304 	free_percpu(xfsstats.xs_stats);
2305  out_kset_unregister:
2306 	kset_unregister(xfs_kset);
2307  out_sysctl_unregister:
2308 	xfs_sysctl_unregister();
2309  out_cleanup_procfs:
2310 	xfs_cleanup_procfs();
2311  out_buf_terminate:
2312 	xfs_buf_terminate();
2313  out_mru_cache_uninit:
2314 	xfs_mru_cache_uninit();
2315  out_destroy_wq:
2316 	xfs_destroy_workqueues();
2317  out_destroy_zones:
2318 	xfs_destroy_zones();
2319  out_destroy_hp:
2320 	xfs_cpu_hotplug_destroy();
2321  out:
2322 	return error;
2323 }
2324 
2325 STATIC void __exit
2326 exit_xfs_fs(void)
2327 {
2328 	xfs_qm_exit();
2329 	unregister_filesystem(&xfs_fs_type);
2330 #ifdef DEBUG
2331 	xfs_sysfs_del(&xfs_dbg_kobj);
2332 #endif
2333 	xfs_sysfs_del(&xfsstats.xs_kobj);
2334 	free_percpu(xfsstats.xs_stats);
2335 	kset_unregister(xfs_kset);
2336 	xfs_sysctl_unregister();
2337 	xfs_cleanup_procfs();
2338 	xfs_buf_terminate();
2339 	xfs_mru_cache_uninit();
2340 	xfs_destroy_workqueues();
2341 	xfs_destroy_zones();
2342 	xfs_uuid_table_free();
2343 	xfs_cpu_hotplug_destroy();
2344 }
2345 
2346 module_init(init_xfs_fs);
2347 module_exit(exit_xfs_fs);
2348 
2349 MODULE_AUTHOR("Silicon Graphics, Inc.");
2350 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2351 MODULE_LICENSE("GPL");
2352