xref: /openbmc/linux/fs/xfs/xfs_super.c (revision 94d964e5)
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 
42 #include <linux/magic.h>
43 #include <linux/fs_context.h>
44 #include <linux/fs_parser.h>
45 
46 static const struct super_operations xfs_super_operations;
47 
48 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
49 #ifdef DEBUG
50 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
51 #endif
52 
53 #ifdef CONFIG_HOTPLUG_CPU
54 static LIST_HEAD(xfs_mount_list);
55 static DEFINE_SPINLOCK(xfs_mount_list_lock);
56 
57 static inline void xfs_mount_list_add(struct xfs_mount *mp)
58 {
59 	spin_lock(&xfs_mount_list_lock);
60 	list_add(&mp->m_mount_list, &xfs_mount_list);
61 	spin_unlock(&xfs_mount_list_lock);
62 }
63 
64 static inline void xfs_mount_list_del(struct xfs_mount *mp)
65 {
66 	spin_lock(&xfs_mount_list_lock);
67 	list_del(&mp->m_mount_list);
68 	spin_unlock(&xfs_mount_list_lock);
69 }
70 #else /* !CONFIG_HOTPLUG_CPU */
71 static inline void xfs_mount_list_add(struct xfs_mount *mp) {}
72 static inline void xfs_mount_list_del(struct xfs_mount *mp) {}
73 #endif
74 
75 enum xfs_dax_mode {
76 	XFS_DAX_INODE = 0,
77 	XFS_DAX_ALWAYS = 1,
78 	XFS_DAX_NEVER = 2,
79 };
80 
81 static void
82 xfs_mount_set_dax_mode(
83 	struct xfs_mount	*mp,
84 	enum xfs_dax_mode	mode)
85 {
86 	switch (mode) {
87 	case XFS_DAX_INODE:
88 		mp->m_features &= ~(XFS_FEAT_DAX_ALWAYS | XFS_FEAT_DAX_NEVER);
89 		break;
90 	case XFS_DAX_ALWAYS:
91 		mp->m_features |= XFS_FEAT_DAX_ALWAYS;
92 		mp->m_features &= ~XFS_FEAT_DAX_NEVER;
93 		break;
94 	case XFS_DAX_NEVER:
95 		mp->m_features |= XFS_FEAT_DAX_NEVER;
96 		mp->m_features &= ~XFS_FEAT_DAX_ALWAYS;
97 		break;
98 	}
99 }
100 
101 static const struct constant_table dax_param_enums[] = {
102 	{"inode",	XFS_DAX_INODE },
103 	{"always",	XFS_DAX_ALWAYS },
104 	{"never",	XFS_DAX_NEVER },
105 	{}
106 };
107 
108 /*
109  * Table driven mount option parser.
110  */
111 enum {
112 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
113 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
114 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
115 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
116 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
117 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
118 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
119 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
120 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
121 };
122 
123 static const struct fs_parameter_spec xfs_fs_parameters[] = {
124 	fsparam_u32("logbufs",		Opt_logbufs),
125 	fsparam_string("logbsize",	Opt_logbsize),
126 	fsparam_string("logdev",	Opt_logdev),
127 	fsparam_string("rtdev",		Opt_rtdev),
128 	fsparam_flag("wsync",		Opt_wsync),
129 	fsparam_flag("noalign",		Opt_noalign),
130 	fsparam_flag("swalloc",		Opt_swalloc),
131 	fsparam_u32("sunit",		Opt_sunit),
132 	fsparam_u32("swidth",		Opt_swidth),
133 	fsparam_flag("nouuid",		Opt_nouuid),
134 	fsparam_flag("grpid",		Opt_grpid),
135 	fsparam_flag("nogrpid",		Opt_nogrpid),
136 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
137 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
138 	fsparam_string("allocsize",	Opt_allocsize),
139 	fsparam_flag("norecovery",	Opt_norecovery),
140 	fsparam_flag("inode64",		Opt_inode64),
141 	fsparam_flag("inode32",		Opt_inode32),
142 	fsparam_flag("ikeep",		Opt_ikeep),
143 	fsparam_flag("noikeep",		Opt_noikeep),
144 	fsparam_flag("largeio",		Opt_largeio),
145 	fsparam_flag("nolargeio",	Opt_nolargeio),
146 	fsparam_flag("attr2",		Opt_attr2),
147 	fsparam_flag("noattr2",		Opt_noattr2),
148 	fsparam_flag("filestreams",	Opt_filestreams),
149 	fsparam_flag("quota",		Opt_quota),
150 	fsparam_flag("noquota",		Opt_noquota),
151 	fsparam_flag("usrquota",	Opt_usrquota),
152 	fsparam_flag("grpquota",	Opt_grpquota),
153 	fsparam_flag("prjquota",	Opt_prjquota),
154 	fsparam_flag("uquota",		Opt_uquota),
155 	fsparam_flag("gquota",		Opt_gquota),
156 	fsparam_flag("pquota",		Opt_pquota),
157 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
158 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
159 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
160 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
161 	fsparam_flag("discard",		Opt_discard),
162 	fsparam_flag("nodiscard",	Opt_nodiscard),
163 	fsparam_flag("dax",		Opt_dax),
164 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
165 	{}
166 };
167 
168 struct proc_xfs_info {
169 	uint64_t	flag;
170 	char		*str;
171 };
172 
173 static int
174 xfs_fs_show_options(
175 	struct seq_file		*m,
176 	struct dentry		*root)
177 {
178 	static struct proc_xfs_info xfs_info_set[] = {
179 		/* the few simple ones we can get from the mount struct */
180 		{ XFS_FEAT_IKEEP,		",ikeep" },
181 		{ XFS_FEAT_WSYNC,		",wsync" },
182 		{ XFS_FEAT_NOALIGN,		",noalign" },
183 		{ XFS_FEAT_SWALLOC,		",swalloc" },
184 		{ XFS_FEAT_NOUUID,		",nouuid" },
185 		{ XFS_FEAT_NORECOVERY,		",norecovery" },
186 		{ XFS_FEAT_ATTR2,		",attr2" },
187 		{ XFS_FEAT_FILESTREAMS,		",filestreams" },
188 		{ XFS_FEAT_GRPID,		",grpid" },
189 		{ XFS_FEAT_DISCARD,		",discard" },
190 		{ XFS_FEAT_LARGE_IOSIZE,	",largeio" },
191 		{ XFS_FEAT_DAX_ALWAYS,		",dax=always" },
192 		{ XFS_FEAT_DAX_NEVER,		",dax=never" },
193 		{ 0, NULL }
194 	};
195 	struct xfs_mount	*mp = XFS_M(root->d_sb);
196 	struct proc_xfs_info	*xfs_infop;
197 
198 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
199 		if (mp->m_features & xfs_infop->flag)
200 			seq_puts(m, xfs_infop->str);
201 	}
202 
203 	seq_printf(m, ",inode%d", xfs_has_small_inums(mp) ? 32 : 64);
204 
205 	if (xfs_has_allocsize(mp))
206 		seq_printf(m, ",allocsize=%dk",
207 			   (1 << mp->m_allocsize_log) >> 10);
208 
209 	if (mp->m_logbufs > 0)
210 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
211 	if (mp->m_logbsize > 0)
212 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
213 
214 	if (mp->m_logname)
215 		seq_show_option(m, "logdev", mp->m_logname);
216 	if (mp->m_rtname)
217 		seq_show_option(m, "rtdev", mp->m_rtname);
218 
219 	if (mp->m_dalign > 0)
220 		seq_printf(m, ",sunit=%d",
221 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
222 	if (mp->m_swidth > 0)
223 		seq_printf(m, ",swidth=%d",
224 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
225 
226 	if (mp->m_qflags & XFS_UQUOTA_ENFD)
227 		seq_puts(m, ",usrquota");
228 	else if (mp->m_qflags & XFS_UQUOTA_ACCT)
229 		seq_puts(m, ",uqnoenforce");
230 
231 	if (mp->m_qflags & XFS_PQUOTA_ENFD)
232 		seq_puts(m, ",prjquota");
233 	else if (mp->m_qflags & XFS_PQUOTA_ACCT)
234 		seq_puts(m, ",pqnoenforce");
235 
236 	if (mp->m_qflags & XFS_GQUOTA_ENFD)
237 		seq_puts(m, ",grpquota");
238 	else if (mp->m_qflags & XFS_GQUOTA_ACCT)
239 		seq_puts(m, ",gqnoenforce");
240 
241 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
242 		seq_puts(m, ",noquota");
243 
244 	return 0;
245 }
246 
247 /*
248  * Set parameters for inode allocation heuristics, taking into account
249  * filesystem size and inode32/inode64 mount options; i.e. specifically
250  * whether or not XFS_FEAT_SMALL_INUMS is set.
251  *
252  * Inode allocation patterns are altered only if inode32 is requested
253  * (XFS_FEAT_SMALL_INUMS), and the filesystem is sufficiently large.
254  * If altered, XFS_OPSTATE_INODE32 is set as well.
255  *
256  * An agcount independent of that in the mount structure is provided
257  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
258  * to the potentially higher ag count.
259  *
260  * Returns the maximum AG index which may contain inodes.
261  */
262 xfs_agnumber_t
263 xfs_set_inode_alloc(
264 	struct xfs_mount *mp,
265 	xfs_agnumber_t	agcount)
266 {
267 	xfs_agnumber_t	index;
268 	xfs_agnumber_t	maxagi = 0;
269 	xfs_sb_t	*sbp = &mp->m_sb;
270 	xfs_agnumber_t	max_metadata;
271 	xfs_agino_t	agino;
272 	xfs_ino_t	ino;
273 
274 	/*
275 	 * Calculate how much should be reserved for inodes to meet
276 	 * the max inode percentage.  Used only for inode32.
277 	 */
278 	if (M_IGEO(mp)->maxicount) {
279 		uint64_t	icount;
280 
281 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
282 		do_div(icount, 100);
283 		icount += sbp->sb_agblocks - 1;
284 		do_div(icount, sbp->sb_agblocks);
285 		max_metadata = icount;
286 	} else {
287 		max_metadata = agcount;
288 	}
289 
290 	/* Get the last possible inode in the filesystem */
291 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
292 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
293 
294 	/*
295 	 * If user asked for no more than 32-bit inodes, and the fs is
296 	 * sufficiently large, set XFS_OPSTATE_INODE32 if we must alter
297 	 * the allocator to accommodate the request.
298 	 */
299 	if (xfs_has_small_inums(mp) && ino > XFS_MAXINUMBER_32)
300 		set_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
301 	else
302 		clear_bit(XFS_OPSTATE_INODE32, &mp->m_opstate);
303 
304 	for (index = 0; index < agcount; index++) {
305 		struct xfs_perag	*pag;
306 
307 		ino = XFS_AGINO_TO_INO(mp, index, agino);
308 
309 		pag = xfs_perag_get(mp, index);
310 
311 		if (xfs_is_inode32(mp)) {
312 			if (ino > XFS_MAXINUMBER_32) {
313 				pag->pagi_inodeok = 0;
314 				pag->pagf_metadata = 0;
315 			} else {
316 				pag->pagi_inodeok = 1;
317 				maxagi++;
318 				if (index < max_metadata)
319 					pag->pagf_metadata = 1;
320 				else
321 					pag->pagf_metadata = 0;
322 			}
323 		} else {
324 			pag->pagi_inodeok = 1;
325 			pag->pagf_metadata = 0;
326 		}
327 
328 		xfs_perag_put(pag);
329 	}
330 
331 	return xfs_is_inode32(mp) ? maxagi : agcount;
332 }
333 
334 static int
335 xfs_setup_dax_always(
336 	struct xfs_mount	*mp)
337 {
338 	if (!mp->m_ddev_targp->bt_daxdev &&
339 	    (!mp->m_rtdev_targp || !mp->m_rtdev_targp->bt_daxdev)) {
340 		xfs_alert(mp,
341 			"DAX unsupported by block device. Turning off DAX.");
342 		goto disable_dax;
343 	}
344 
345 	if (mp->m_super->s_blocksize != PAGE_SIZE) {
346 		xfs_alert(mp,
347 			"DAX not supported for blocksize. Turning off DAX.");
348 		goto disable_dax;
349 	}
350 
351 	if (xfs_has_reflink(mp)) {
352 		xfs_alert(mp, "DAX and reflink cannot be used together!");
353 		return -EINVAL;
354 	}
355 
356 	xfs_warn(mp, "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
357 	return 0;
358 
359 disable_dax:
360 	xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
361 	return 0;
362 }
363 
364 STATIC int
365 xfs_blkdev_get(
366 	xfs_mount_t		*mp,
367 	const char		*name,
368 	struct block_device	**bdevp)
369 {
370 	int			error = 0;
371 
372 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
373 				    mp);
374 	if (IS_ERR(*bdevp)) {
375 		error = PTR_ERR(*bdevp);
376 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
377 	}
378 
379 	return error;
380 }
381 
382 STATIC void
383 xfs_blkdev_put(
384 	struct block_device	*bdev)
385 {
386 	if (bdev)
387 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
388 }
389 
390 STATIC void
391 xfs_close_devices(
392 	struct xfs_mount	*mp)
393 {
394 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
395 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
396 
397 		xfs_free_buftarg(mp->m_logdev_targp);
398 		xfs_blkdev_put(logdev);
399 	}
400 	if (mp->m_rtdev_targp) {
401 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
402 
403 		xfs_free_buftarg(mp->m_rtdev_targp);
404 		xfs_blkdev_put(rtdev);
405 	}
406 	xfs_free_buftarg(mp->m_ddev_targp);
407 }
408 
409 /*
410  * The file system configurations are:
411  *	(1) device (partition) with data and internal log
412  *	(2) logical volume with data and log subvolumes.
413  *	(3) logical volume with data, log, and realtime subvolumes.
414  *
415  * We only have to handle opening the log and realtime volumes here if
416  * they are present.  The data subvolume has already been opened by
417  * get_sb_bdev() and is stored in sb->s_bdev.
418  */
419 STATIC int
420 xfs_open_devices(
421 	struct xfs_mount	*mp)
422 {
423 	struct block_device	*ddev = mp->m_super->s_bdev;
424 	struct block_device	*logdev = NULL, *rtdev = NULL;
425 	int			error;
426 
427 	/*
428 	 * Open real time and log devices - order is important.
429 	 */
430 	if (mp->m_logname) {
431 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
432 		if (error)
433 			return error;
434 	}
435 
436 	if (mp->m_rtname) {
437 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
438 		if (error)
439 			goto out_close_logdev;
440 
441 		if (rtdev == ddev || rtdev == logdev) {
442 			xfs_warn(mp,
443 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
444 			error = -EINVAL;
445 			goto out_close_rtdev;
446 		}
447 	}
448 
449 	/*
450 	 * Setup xfs_mount buffer target pointers
451 	 */
452 	error = -ENOMEM;
453 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev);
454 	if (!mp->m_ddev_targp)
455 		goto out_close_rtdev;
456 
457 	if (rtdev) {
458 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev);
459 		if (!mp->m_rtdev_targp)
460 			goto out_free_ddev_targ;
461 	}
462 
463 	if (logdev && logdev != ddev) {
464 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev);
465 		if (!mp->m_logdev_targp)
466 			goto out_free_rtdev_targ;
467 	} else {
468 		mp->m_logdev_targp = mp->m_ddev_targp;
469 	}
470 
471 	return 0;
472 
473  out_free_rtdev_targ:
474 	if (mp->m_rtdev_targp)
475 		xfs_free_buftarg(mp->m_rtdev_targp);
476  out_free_ddev_targ:
477 	xfs_free_buftarg(mp->m_ddev_targp);
478  out_close_rtdev:
479 	xfs_blkdev_put(rtdev);
480  out_close_logdev:
481 	if (logdev && logdev != ddev)
482 		xfs_blkdev_put(logdev);
483 	return error;
484 }
485 
486 /*
487  * Setup xfs_mount buffer target pointers based on superblock
488  */
489 STATIC int
490 xfs_setup_devices(
491 	struct xfs_mount	*mp)
492 {
493 	int			error;
494 
495 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
496 	if (error)
497 		return error;
498 
499 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
500 		unsigned int	log_sector_size = BBSIZE;
501 
502 		if (xfs_has_sector(mp))
503 			log_sector_size = mp->m_sb.sb_logsectsize;
504 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
505 					    log_sector_size);
506 		if (error)
507 			return error;
508 	}
509 	if (mp->m_rtdev_targp) {
510 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
511 					    mp->m_sb.sb_sectsize);
512 		if (error)
513 			return error;
514 	}
515 
516 	return 0;
517 }
518 
519 STATIC int
520 xfs_init_mount_workqueues(
521 	struct xfs_mount	*mp)
522 {
523 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
524 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
525 			1, mp->m_super->s_id);
526 	if (!mp->m_buf_workqueue)
527 		goto out;
528 
529 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
530 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
531 			0, mp->m_super->s_id);
532 	if (!mp->m_unwritten_workqueue)
533 		goto out_destroy_buf;
534 
535 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
536 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
537 			0, mp->m_super->s_id);
538 	if (!mp->m_reclaim_workqueue)
539 		goto out_destroy_unwritten;
540 
541 	mp->m_blockgc_wq = alloc_workqueue("xfs-blockgc/%s",
542 			XFS_WQFLAGS(WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM),
543 			0, mp->m_super->s_id);
544 	if (!mp->m_blockgc_wq)
545 		goto out_destroy_reclaim;
546 
547 	mp->m_inodegc_wq = alloc_workqueue("xfs-inodegc/%s",
548 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
549 			1, mp->m_super->s_id);
550 	if (!mp->m_inodegc_wq)
551 		goto out_destroy_blockgc;
552 
553 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
554 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
555 	if (!mp->m_sync_workqueue)
556 		goto out_destroy_inodegc;
557 
558 	return 0;
559 
560 out_destroy_inodegc:
561 	destroy_workqueue(mp->m_inodegc_wq);
562 out_destroy_blockgc:
563 	destroy_workqueue(mp->m_blockgc_wq);
564 out_destroy_reclaim:
565 	destroy_workqueue(mp->m_reclaim_workqueue);
566 out_destroy_unwritten:
567 	destroy_workqueue(mp->m_unwritten_workqueue);
568 out_destroy_buf:
569 	destroy_workqueue(mp->m_buf_workqueue);
570 out:
571 	return -ENOMEM;
572 }
573 
574 STATIC void
575 xfs_destroy_mount_workqueues(
576 	struct xfs_mount	*mp)
577 {
578 	destroy_workqueue(mp->m_sync_workqueue);
579 	destroy_workqueue(mp->m_blockgc_wq);
580 	destroy_workqueue(mp->m_inodegc_wq);
581 	destroy_workqueue(mp->m_reclaim_workqueue);
582 	destroy_workqueue(mp->m_unwritten_workqueue);
583 	destroy_workqueue(mp->m_buf_workqueue);
584 }
585 
586 static void
587 xfs_flush_inodes_worker(
588 	struct work_struct	*work)
589 {
590 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
591 						   m_flush_inodes_work);
592 	struct super_block	*sb = mp->m_super;
593 
594 	if (down_read_trylock(&sb->s_umount)) {
595 		sync_inodes_sb(sb);
596 		up_read(&sb->s_umount);
597 	}
598 }
599 
600 /*
601  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
602  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
603  * for IO to complete so that we effectively throttle multiple callers to the
604  * rate at which IO is completing.
605  */
606 void
607 xfs_flush_inodes(
608 	struct xfs_mount	*mp)
609 {
610 	/*
611 	 * If flush_work() returns true then that means we waited for a flush
612 	 * which was already in progress.  Don't bother running another scan.
613 	 */
614 	if (flush_work(&mp->m_flush_inodes_work))
615 		return;
616 
617 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
618 	flush_work(&mp->m_flush_inodes_work);
619 }
620 
621 /* Catch misguided souls that try to use this interface on XFS */
622 STATIC struct inode *
623 xfs_fs_alloc_inode(
624 	struct super_block	*sb)
625 {
626 	BUG();
627 	return NULL;
628 }
629 
630 /*
631  * Now that the generic code is guaranteed not to be accessing
632  * the linux inode, we can inactivate and reclaim the inode.
633  */
634 STATIC void
635 xfs_fs_destroy_inode(
636 	struct inode		*inode)
637 {
638 	struct xfs_inode	*ip = XFS_I(inode);
639 
640 	trace_xfs_destroy_inode(ip);
641 
642 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
643 	XFS_STATS_INC(ip->i_mount, vn_rele);
644 	XFS_STATS_INC(ip->i_mount, vn_remove);
645 	xfs_inode_mark_reclaimable(ip);
646 }
647 
648 static void
649 xfs_fs_dirty_inode(
650 	struct inode			*inode,
651 	int				flag)
652 {
653 	struct xfs_inode		*ip = XFS_I(inode);
654 	struct xfs_mount		*mp = ip->i_mount;
655 	struct xfs_trans		*tp;
656 
657 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
658 		return;
659 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
660 		return;
661 
662 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
663 		return;
664 	xfs_ilock(ip, XFS_ILOCK_EXCL);
665 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
666 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
667 	xfs_trans_commit(tp);
668 }
669 
670 /*
671  * Slab object creation initialisation for the XFS inode.
672  * This covers only the idempotent fields in the XFS inode;
673  * all other fields need to be initialised on allocation
674  * from the slab. This avoids the need to repeatedly initialise
675  * fields in the xfs inode that left in the initialise state
676  * when freeing the inode.
677  */
678 STATIC void
679 xfs_fs_inode_init_once(
680 	void			*inode)
681 {
682 	struct xfs_inode	*ip = inode;
683 
684 	memset(ip, 0, sizeof(struct xfs_inode));
685 
686 	/* vfs inode */
687 	inode_init_once(VFS_I(ip));
688 
689 	/* xfs inode */
690 	atomic_set(&ip->i_pincount, 0);
691 	spin_lock_init(&ip->i_flags_lock);
692 
693 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
694 		     "xfsino", ip->i_ino);
695 }
696 
697 /*
698  * We do an unlocked check for XFS_IDONTCACHE here because we are already
699  * serialised against cache hits here via the inode->i_lock and igrab() in
700  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
701  * racing with us, and it avoids needing to grab a spinlock here for every inode
702  * we drop the final reference on.
703  */
704 STATIC int
705 xfs_fs_drop_inode(
706 	struct inode		*inode)
707 {
708 	struct xfs_inode	*ip = XFS_I(inode);
709 
710 	/*
711 	 * If this unlinked inode is in the middle of recovery, don't
712 	 * drop the inode just yet; log recovery will take care of
713 	 * that.  See the comment for this inode flag.
714 	 */
715 	if (ip->i_flags & XFS_IRECOVERY) {
716 		ASSERT(xlog_recovery_needed(ip->i_mount->m_log));
717 		return 0;
718 	}
719 
720 	return generic_drop_inode(inode);
721 }
722 
723 static void
724 xfs_mount_free(
725 	struct xfs_mount	*mp)
726 {
727 	kfree(mp->m_rtname);
728 	kfree(mp->m_logname);
729 	kmem_free(mp);
730 }
731 
732 STATIC int
733 xfs_fs_sync_fs(
734 	struct super_block	*sb,
735 	int			wait)
736 {
737 	struct xfs_mount	*mp = XFS_M(sb);
738 
739 	trace_xfs_fs_sync_fs(mp, __return_address);
740 
741 	/*
742 	 * Doing anything during the async pass would be counterproductive.
743 	 */
744 	if (!wait)
745 		return 0;
746 
747 	xfs_log_force(mp, XFS_LOG_SYNC);
748 	if (laptop_mode) {
749 		/*
750 		 * The disk must be active because we're syncing.
751 		 * We schedule log work now (now that the disk is
752 		 * active) instead of later (when it might not be).
753 		 */
754 		flush_delayed_work(&mp->m_log->l_work);
755 	}
756 
757 	/*
758 	 * If we are called with page faults frozen out, it means we are about
759 	 * to freeze the transaction subsystem. Take the opportunity to shut
760 	 * down inodegc because once SB_FREEZE_FS is set it's too late to
761 	 * prevent inactivation races with freeze. The fs doesn't get called
762 	 * again by the freezing process until after SB_FREEZE_FS has been set,
763 	 * so it's now or never.  Same logic applies to speculative allocation
764 	 * garbage collection.
765 	 *
766 	 * We don't care if this is a normal syncfs call that does this or
767 	 * freeze that does this - we can run this multiple times without issue
768 	 * and we won't race with a restart because a restart can only occur
769 	 * when the state is either SB_FREEZE_FS or SB_FREEZE_COMPLETE.
770 	 */
771 	if (sb->s_writers.frozen == SB_FREEZE_PAGEFAULT) {
772 		xfs_inodegc_stop(mp);
773 		xfs_blockgc_stop(mp);
774 	}
775 
776 	return 0;
777 }
778 
779 STATIC int
780 xfs_fs_statfs(
781 	struct dentry		*dentry,
782 	struct kstatfs		*statp)
783 {
784 	struct xfs_mount	*mp = XFS_M(dentry->d_sb);
785 	xfs_sb_t		*sbp = &mp->m_sb;
786 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
787 	uint64_t		fakeinos, id;
788 	uint64_t		icount;
789 	uint64_t		ifree;
790 	uint64_t		fdblocks;
791 	xfs_extlen_t		lsize;
792 	int64_t			ffree;
793 
794 	/* Wait for whatever inactivations are in progress. */
795 	xfs_inodegc_flush(mp);
796 
797 	statp->f_type = XFS_SUPER_MAGIC;
798 	statp->f_namelen = MAXNAMELEN - 1;
799 
800 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
801 	statp->f_fsid = u64_to_fsid(id);
802 
803 	icount = percpu_counter_sum(&mp->m_icount);
804 	ifree = percpu_counter_sum(&mp->m_ifree);
805 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
806 
807 	spin_lock(&mp->m_sb_lock);
808 	statp->f_bsize = sbp->sb_blocksize;
809 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
810 	statp->f_blocks = sbp->sb_dblocks - lsize;
811 	spin_unlock(&mp->m_sb_lock);
812 
813 	/* make sure statp->f_bfree does not underflow */
814 	statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0);
815 	statp->f_bavail = statp->f_bfree;
816 
817 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
818 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
819 	if (M_IGEO(mp)->maxicount)
820 		statp->f_files = min_t(typeof(statp->f_files),
821 					statp->f_files,
822 					M_IGEO(mp)->maxicount);
823 
824 	/* If sb_icount overshot maxicount, report actual allocation */
825 	statp->f_files = max_t(typeof(statp->f_files),
826 					statp->f_files,
827 					sbp->sb_icount);
828 
829 	/* make sure statp->f_ffree does not underflow */
830 	ffree = statp->f_files - (icount - ifree);
831 	statp->f_ffree = max_t(int64_t, ffree, 0);
832 
833 
834 	if ((ip->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
835 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
836 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
837 		xfs_qm_statvfs(ip, statp);
838 
839 	if (XFS_IS_REALTIME_MOUNT(mp) &&
840 	    (ip->i_diflags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
841 		statp->f_blocks = sbp->sb_rblocks;
842 		statp->f_bavail = statp->f_bfree =
843 			sbp->sb_frextents * sbp->sb_rextsize;
844 	}
845 
846 	return 0;
847 }
848 
849 STATIC void
850 xfs_save_resvblks(struct xfs_mount *mp)
851 {
852 	uint64_t resblks = 0;
853 
854 	mp->m_resblks_save = mp->m_resblks;
855 	xfs_reserve_blocks(mp, &resblks, NULL);
856 }
857 
858 STATIC void
859 xfs_restore_resvblks(struct xfs_mount *mp)
860 {
861 	uint64_t resblks;
862 
863 	if (mp->m_resblks_save) {
864 		resblks = mp->m_resblks_save;
865 		mp->m_resblks_save = 0;
866 	} else
867 		resblks = xfs_default_resblks(mp);
868 
869 	xfs_reserve_blocks(mp, &resblks, NULL);
870 }
871 
872 /*
873  * Second stage of a freeze. The data is already frozen so we only
874  * need to take care of the metadata. Once that's done sync the superblock
875  * to the log to dirty it in case of a crash while frozen. This ensures that we
876  * will recover the unlinked inode lists on the next mount.
877  */
878 STATIC int
879 xfs_fs_freeze(
880 	struct super_block	*sb)
881 {
882 	struct xfs_mount	*mp = XFS_M(sb);
883 	unsigned int		flags;
884 	int			ret;
885 
886 	/*
887 	 * The filesystem is now frozen far enough that memory reclaim
888 	 * cannot safely operate on the filesystem. Hence we need to
889 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
890 	 */
891 	flags = memalloc_nofs_save();
892 	xfs_save_resvblks(mp);
893 	ret = xfs_log_quiesce(mp);
894 	memalloc_nofs_restore(flags);
895 
896 	/*
897 	 * For read-write filesystems, we need to restart the inodegc on error
898 	 * because we stopped it at SB_FREEZE_PAGEFAULT level and a thaw is not
899 	 * going to be run to restart it now.  We are at SB_FREEZE_FS level
900 	 * here, so we can restart safely without racing with a stop in
901 	 * xfs_fs_sync_fs().
902 	 */
903 	if (ret && !xfs_is_readonly(mp)) {
904 		xfs_blockgc_start(mp);
905 		xfs_inodegc_start(mp);
906 	}
907 
908 	return ret;
909 }
910 
911 STATIC int
912 xfs_fs_unfreeze(
913 	struct super_block	*sb)
914 {
915 	struct xfs_mount	*mp = XFS_M(sb);
916 
917 	xfs_restore_resvblks(mp);
918 	xfs_log_work_queue(mp);
919 
920 	/*
921 	 * Don't reactivate the inodegc worker on a readonly filesystem because
922 	 * inodes are sent directly to reclaim.  Don't reactivate the blockgc
923 	 * worker because there are no speculative preallocations on a readonly
924 	 * filesystem.
925 	 */
926 	if (!xfs_is_readonly(mp)) {
927 		xfs_blockgc_start(mp);
928 		xfs_inodegc_start(mp);
929 	}
930 
931 	return 0;
932 }
933 
934 /*
935  * This function fills in xfs_mount_t fields based on mount args.
936  * Note: the superblock _has_ now been read in.
937  */
938 STATIC int
939 xfs_finish_flags(
940 	struct xfs_mount	*mp)
941 {
942 	/* Fail a mount where the logbuf is smaller than the log stripe */
943 	if (xfs_has_logv2(mp)) {
944 		if (mp->m_logbsize <= 0 &&
945 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
946 			mp->m_logbsize = mp->m_sb.sb_logsunit;
947 		} else if (mp->m_logbsize > 0 &&
948 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
949 			xfs_warn(mp,
950 		"logbuf size must be greater than or equal to log stripe size");
951 			return -EINVAL;
952 		}
953 	} else {
954 		/* Fail a mount if the logbuf is larger than 32K */
955 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
956 			xfs_warn(mp,
957 		"logbuf size for version 1 logs must be 16K or 32K");
958 			return -EINVAL;
959 		}
960 	}
961 
962 	/*
963 	 * V5 filesystems always use attr2 format for attributes.
964 	 */
965 	if (xfs_has_crc(mp) && xfs_has_noattr2(mp)) {
966 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
967 			     "attr2 is always enabled for V5 filesystems.");
968 		return -EINVAL;
969 	}
970 
971 	/*
972 	 * prohibit r/w mounts of read-only filesystems
973 	 */
974 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !xfs_is_readonly(mp)) {
975 		xfs_warn(mp,
976 			"cannot mount a read-only filesystem as read-write");
977 		return -EROFS;
978 	}
979 
980 	if ((mp->m_qflags & XFS_GQUOTA_ACCT) &&
981 	    (mp->m_qflags & XFS_PQUOTA_ACCT) &&
982 	    !xfs_has_pquotino(mp)) {
983 		xfs_warn(mp,
984 		  "Super block does not support project and group quota together");
985 		return -EINVAL;
986 	}
987 
988 	return 0;
989 }
990 
991 static int
992 xfs_init_percpu_counters(
993 	struct xfs_mount	*mp)
994 {
995 	int		error;
996 
997 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
998 	if (error)
999 		return -ENOMEM;
1000 
1001 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
1002 	if (error)
1003 		goto free_icount;
1004 
1005 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
1006 	if (error)
1007 		goto free_ifree;
1008 
1009 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
1010 	if (error)
1011 		goto free_fdblocks;
1012 
1013 	return 0;
1014 
1015 free_fdblocks:
1016 	percpu_counter_destroy(&mp->m_fdblocks);
1017 free_ifree:
1018 	percpu_counter_destroy(&mp->m_ifree);
1019 free_icount:
1020 	percpu_counter_destroy(&mp->m_icount);
1021 	return -ENOMEM;
1022 }
1023 
1024 void
1025 xfs_reinit_percpu_counters(
1026 	struct xfs_mount	*mp)
1027 {
1028 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1029 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1030 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1031 }
1032 
1033 static void
1034 xfs_destroy_percpu_counters(
1035 	struct xfs_mount	*mp)
1036 {
1037 	percpu_counter_destroy(&mp->m_icount);
1038 	percpu_counter_destroy(&mp->m_ifree);
1039 	percpu_counter_destroy(&mp->m_fdblocks);
1040 	ASSERT(xfs_is_shutdown(mp) ||
1041 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1042 	percpu_counter_destroy(&mp->m_delalloc_blks);
1043 }
1044 
1045 static int
1046 xfs_inodegc_init_percpu(
1047 	struct xfs_mount	*mp)
1048 {
1049 	struct xfs_inodegc	*gc;
1050 	int			cpu;
1051 
1052 	mp->m_inodegc = alloc_percpu(struct xfs_inodegc);
1053 	if (!mp->m_inodegc)
1054 		return -ENOMEM;
1055 
1056 	for_each_possible_cpu(cpu) {
1057 		gc = per_cpu_ptr(mp->m_inodegc, cpu);
1058 		init_llist_head(&gc->list);
1059 		gc->items = 0;
1060 		INIT_WORK(&gc->work, xfs_inodegc_worker);
1061 	}
1062 	return 0;
1063 }
1064 
1065 static void
1066 xfs_inodegc_free_percpu(
1067 	struct xfs_mount	*mp)
1068 {
1069 	if (!mp->m_inodegc)
1070 		return;
1071 	free_percpu(mp->m_inodegc);
1072 }
1073 
1074 static void
1075 xfs_fs_put_super(
1076 	struct super_block	*sb)
1077 {
1078 	struct xfs_mount	*mp = XFS_M(sb);
1079 
1080 	/* if ->fill_super failed, we have no mount to tear down */
1081 	if (!sb->s_fs_info)
1082 		return;
1083 
1084 	xfs_notice(mp, "Unmounting Filesystem");
1085 	xfs_filestream_unmount(mp);
1086 	xfs_unmountfs(mp);
1087 
1088 	xfs_freesb(mp);
1089 	free_percpu(mp->m_stats.xs_stats);
1090 	xfs_mount_list_del(mp);
1091 	xfs_inodegc_free_percpu(mp);
1092 	xfs_destroy_percpu_counters(mp);
1093 	xfs_destroy_mount_workqueues(mp);
1094 	xfs_close_devices(mp);
1095 
1096 	sb->s_fs_info = NULL;
1097 	xfs_mount_free(mp);
1098 }
1099 
1100 static long
1101 xfs_fs_nr_cached_objects(
1102 	struct super_block	*sb,
1103 	struct shrink_control	*sc)
1104 {
1105 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1106 	if (WARN_ON_ONCE(!sb->s_fs_info))
1107 		return 0;
1108 	return xfs_reclaim_inodes_count(XFS_M(sb));
1109 }
1110 
1111 static long
1112 xfs_fs_free_cached_objects(
1113 	struct super_block	*sb,
1114 	struct shrink_control	*sc)
1115 {
1116 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1117 }
1118 
1119 static const struct super_operations xfs_super_operations = {
1120 	.alloc_inode		= xfs_fs_alloc_inode,
1121 	.destroy_inode		= xfs_fs_destroy_inode,
1122 	.dirty_inode		= xfs_fs_dirty_inode,
1123 	.drop_inode		= xfs_fs_drop_inode,
1124 	.put_super		= xfs_fs_put_super,
1125 	.sync_fs		= xfs_fs_sync_fs,
1126 	.freeze_fs		= xfs_fs_freeze,
1127 	.unfreeze_fs		= xfs_fs_unfreeze,
1128 	.statfs			= xfs_fs_statfs,
1129 	.show_options		= xfs_fs_show_options,
1130 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1131 	.free_cached_objects	= xfs_fs_free_cached_objects,
1132 };
1133 
1134 static int
1135 suffix_kstrtoint(
1136 	const char	*s,
1137 	unsigned int	base,
1138 	int		*res)
1139 {
1140 	int		last, shift_left_factor = 0, _res;
1141 	char		*value;
1142 	int		ret = 0;
1143 
1144 	value = kstrdup(s, GFP_KERNEL);
1145 	if (!value)
1146 		return -ENOMEM;
1147 
1148 	last = strlen(value) - 1;
1149 	if (value[last] == 'K' || value[last] == 'k') {
1150 		shift_left_factor = 10;
1151 		value[last] = '\0';
1152 	}
1153 	if (value[last] == 'M' || value[last] == 'm') {
1154 		shift_left_factor = 20;
1155 		value[last] = '\0';
1156 	}
1157 	if (value[last] == 'G' || value[last] == 'g') {
1158 		shift_left_factor = 30;
1159 		value[last] = '\0';
1160 	}
1161 
1162 	if (kstrtoint(value, base, &_res))
1163 		ret = -EINVAL;
1164 	kfree(value);
1165 	*res = _res << shift_left_factor;
1166 	return ret;
1167 }
1168 
1169 static inline void
1170 xfs_fs_warn_deprecated(
1171 	struct fs_context	*fc,
1172 	struct fs_parameter	*param,
1173 	uint64_t		flag,
1174 	bool			value)
1175 {
1176 	/* Don't print the warning if reconfiguring and current mount point
1177 	 * already had the flag set
1178 	 */
1179 	if ((fc->purpose & FS_CONTEXT_FOR_RECONFIGURE) &&
1180             !!(XFS_M(fc->root->d_sb)->m_features & flag) == value)
1181 		return;
1182 	xfs_warn(fc->s_fs_info, "%s mount option is deprecated.", param->key);
1183 }
1184 
1185 /*
1186  * Set mount state from a mount option.
1187  *
1188  * NOTE: mp->m_super is NULL here!
1189  */
1190 static int
1191 xfs_fs_parse_param(
1192 	struct fs_context	*fc,
1193 	struct fs_parameter	*param)
1194 {
1195 	struct xfs_mount	*parsing_mp = fc->s_fs_info;
1196 	struct fs_parse_result	result;
1197 	int			size = 0;
1198 	int			opt;
1199 
1200 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1201 	if (opt < 0)
1202 		return opt;
1203 
1204 	switch (opt) {
1205 	case Opt_logbufs:
1206 		parsing_mp->m_logbufs = result.uint_32;
1207 		return 0;
1208 	case Opt_logbsize:
1209 		if (suffix_kstrtoint(param->string, 10, &parsing_mp->m_logbsize))
1210 			return -EINVAL;
1211 		return 0;
1212 	case Opt_logdev:
1213 		kfree(parsing_mp->m_logname);
1214 		parsing_mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1215 		if (!parsing_mp->m_logname)
1216 			return -ENOMEM;
1217 		return 0;
1218 	case Opt_rtdev:
1219 		kfree(parsing_mp->m_rtname);
1220 		parsing_mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1221 		if (!parsing_mp->m_rtname)
1222 			return -ENOMEM;
1223 		return 0;
1224 	case Opt_allocsize:
1225 		if (suffix_kstrtoint(param->string, 10, &size))
1226 			return -EINVAL;
1227 		parsing_mp->m_allocsize_log = ffs(size) - 1;
1228 		parsing_mp->m_features |= XFS_FEAT_ALLOCSIZE;
1229 		return 0;
1230 	case Opt_grpid:
1231 	case Opt_bsdgroups:
1232 		parsing_mp->m_features |= XFS_FEAT_GRPID;
1233 		return 0;
1234 	case Opt_nogrpid:
1235 	case Opt_sysvgroups:
1236 		parsing_mp->m_features &= ~XFS_FEAT_GRPID;
1237 		return 0;
1238 	case Opt_wsync:
1239 		parsing_mp->m_features |= XFS_FEAT_WSYNC;
1240 		return 0;
1241 	case Opt_norecovery:
1242 		parsing_mp->m_features |= XFS_FEAT_NORECOVERY;
1243 		return 0;
1244 	case Opt_noalign:
1245 		parsing_mp->m_features |= XFS_FEAT_NOALIGN;
1246 		return 0;
1247 	case Opt_swalloc:
1248 		parsing_mp->m_features |= XFS_FEAT_SWALLOC;
1249 		return 0;
1250 	case Opt_sunit:
1251 		parsing_mp->m_dalign = result.uint_32;
1252 		return 0;
1253 	case Opt_swidth:
1254 		parsing_mp->m_swidth = result.uint_32;
1255 		return 0;
1256 	case Opt_inode32:
1257 		parsing_mp->m_features |= XFS_FEAT_SMALL_INUMS;
1258 		return 0;
1259 	case Opt_inode64:
1260 		parsing_mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1261 		return 0;
1262 	case Opt_nouuid:
1263 		parsing_mp->m_features |= XFS_FEAT_NOUUID;
1264 		return 0;
1265 	case Opt_largeio:
1266 		parsing_mp->m_features |= XFS_FEAT_LARGE_IOSIZE;
1267 		return 0;
1268 	case Opt_nolargeio:
1269 		parsing_mp->m_features &= ~XFS_FEAT_LARGE_IOSIZE;
1270 		return 0;
1271 	case Opt_filestreams:
1272 		parsing_mp->m_features |= XFS_FEAT_FILESTREAMS;
1273 		return 0;
1274 	case Opt_noquota:
1275 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1276 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1277 		return 0;
1278 	case Opt_quota:
1279 	case Opt_uquota:
1280 	case Opt_usrquota:
1281 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ENFD);
1282 		return 0;
1283 	case Opt_qnoenforce:
1284 	case Opt_uqnoenforce:
1285 		parsing_mp->m_qflags |= XFS_UQUOTA_ACCT;
1286 		parsing_mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1287 		return 0;
1288 	case Opt_pquota:
1289 	case Opt_prjquota:
1290 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ENFD);
1291 		return 0;
1292 	case Opt_pqnoenforce:
1293 		parsing_mp->m_qflags |= XFS_PQUOTA_ACCT;
1294 		parsing_mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1295 		return 0;
1296 	case Opt_gquota:
1297 	case Opt_grpquota:
1298 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ENFD);
1299 		return 0;
1300 	case Opt_gqnoenforce:
1301 		parsing_mp->m_qflags |= XFS_GQUOTA_ACCT;
1302 		parsing_mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1303 		return 0;
1304 	case Opt_discard:
1305 		parsing_mp->m_features |= XFS_FEAT_DISCARD;
1306 		return 0;
1307 	case Opt_nodiscard:
1308 		parsing_mp->m_features &= ~XFS_FEAT_DISCARD;
1309 		return 0;
1310 #ifdef CONFIG_FS_DAX
1311 	case Opt_dax:
1312 		xfs_mount_set_dax_mode(parsing_mp, XFS_DAX_ALWAYS);
1313 		return 0;
1314 	case Opt_dax_enum:
1315 		xfs_mount_set_dax_mode(parsing_mp, result.uint_32);
1316 		return 0;
1317 #endif
1318 	/* Following mount options will be removed in September 2025 */
1319 	case Opt_ikeep:
1320 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, true);
1321 		parsing_mp->m_features |= XFS_FEAT_IKEEP;
1322 		return 0;
1323 	case Opt_noikeep:
1324 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_IKEEP, false);
1325 		parsing_mp->m_features &= ~XFS_FEAT_IKEEP;
1326 		return 0;
1327 	case Opt_attr2:
1328 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_ATTR2, true);
1329 		parsing_mp->m_features |= XFS_FEAT_ATTR2;
1330 		return 0;
1331 	case Opt_noattr2:
1332 		xfs_fs_warn_deprecated(fc, param, XFS_FEAT_NOATTR2, true);
1333 		parsing_mp->m_features |= XFS_FEAT_NOATTR2;
1334 		return 0;
1335 	default:
1336 		xfs_warn(parsing_mp, "unknown mount option [%s].", param->key);
1337 		return -EINVAL;
1338 	}
1339 
1340 	return 0;
1341 }
1342 
1343 static int
1344 xfs_fs_validate_params(
1345 	struct xfs_mount	*mp)
1346 {
1347 	/* No recovery flag requires a read-only mount */
1348 	if (xfs_has_norecovery(mp) && !xfs_is_readonly(mp)) {
1349 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1350 		return -EINVAL;
1351 	}
1352 
1353 	/*
1354 	 * We have not read the superblock at this point, so only the attr2
1355 	 * mount option can set the attr2 feature by this stage.
1356 	 */
1357 	if (xfs_has_attr2(mp) && xfs_has_noattr2(mp)) {
1358 		xfs_warn(mp, "attr2 and noattr2 cannot both be specified.");
1359 		return -EINVAL;
1360 	}
1361 
1362 
1363 	if (xfs_has_noalign(mp) && (mp->m_dalign || mp->m_swidth)) {
1364 		xfs_warn(mp,
1365 	"sunit and swidth options incompatible with the noalign option");
1366 		return -EINVAL;
1367 	}
1368 
1369 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1370 		xfs_warn(mp, "quota support not available in this kernel.");
1371 		return -EINVAL;
1372 	}
1373 
1374 	if ((mp->m_dalign && !mp->m_swidth) ||
1375 	    (!mp->m_dalign && mp->m_swidth)) {
1376 		xfs_warn(mp, "sunit and swidth must be specified together");
1377 		return -EINVAL;
1378 	}
1379 
1380 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1381 		xfs_warn(mp,
1382 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1383 			mp->m_swidth, mp->m_dalign);
1384 		return -EINVAL;
1385 	}
1386 
1387 	if (mp->m_logbufs != -1 &&
1388 	    mp->m_logbufs != 0 &&
1389 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1390 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1391 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1392 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1393 		return -EINVAL;
1394 	}
1395 
1396 	if (mp->m_logbsize != -1 &&
1397 	    mp->m_logbsize !=  0 &&
1398 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1399 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1400 	     !is_power_of_2(mp->m_logbsize))) {
1401 		xfs_warn(mp,
1402 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1403 			mp->m_logbsize);
1404 		return -EINVAL;
1405 	}
1406 
1407 	if (xfs_has_allocsize(mp) &&
1408 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1409 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1410 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1411 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1412 		return -EINVAL;
1413 	}
1414 
1415 	return 0;
1416 }
1417 
1418 static int
1419 xfs_fs_fill_super(
1420 	struct super_block	*sb,
1421 	struct fs_context	*fc)
1422 {
1423 	struct xfs_mount	*mp = sb->s_fs_info;
1424 	struct inode		*root;
1425 	int			flags = 0, error;
1426 
1427 	mp->m_super = sb;
1428 
1429 	error = xfs_fs_validate_params(mp);
1430 	if (error)
1431 		goto out_free_names;
1432 
1433 	sb_min_blocksize(sb, BBSIZE);
1434 	sb->s_xattr = xfs_xattr_handlers;
1435 	sb->s_export_op = &xfs_export_operations;
1436 #ifdef CONFIG_XFS_QUOTA
1437 	sb->s_qcop = &xfs_quotactl_operations;
1438 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1439 #endif
1440 	sb->s_op = &xfs_super_operations;
1441 
1442 	/*
1443 	 * Delay mount work if the debug hook is set. This is debug
1444 	 * instrumention to coordinate simulation of xfs mount failures with
1445 	 * VFS superblock operations
1446 	 */
1447 	if (xfs_globals.mount_delay) {
1448 		xfs_notice(mp, "Delaying mount for %d seconds.",
1449 			xfs_globals.mount_delay);
1450 		msleep(xfs_globals.mount_delay * 1000);
1451 	}
1452 
1453 	if (fc->sb_flags & SB_SILENT)
1454 		flags |= XFS_MFSI_QUIET;
1455 
1456 	error = xfs_open_devices(mp);
1457 	if (error)
1458 		goto out_free_names;
1459 
1460 	error = xfs_init_mount_workqueues(mp);
1461 	if (error)
1462 		goto out_close_devices;
1463 
1464 	error = xfs_init_percpu_counters(mp);
1465 	if (error)
1466 		goto out_destroy_workqueues;
1467 
1468 	error = xfs_inodegc_init_percpu(mp);
1469 	if (error)
1470 		goto out_destroy_counters;
1471 
1472 	/*
1473 	 * All percpu data structures requiring cleanup when a cpu goes offline
1474 	 * must be allocated before adding this @mp to the cpu-dead handler's
1475 	 * mount list.
1476 	 */
1477 	xfs_mount_list_add(mp);
1478 
1479 	/* Allocate stats memory before we do operations that might use it */
1480 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1481 	if (!mp->m_stats.xs_stats) {
1482 		error = -ENOMEM;
1483 		goto out_destroy_inodegc;
1484 	}
1485 
1486 	error = xfs_readsb(mp, flags);
1487 	if (error)
1488 		goto out_free_stats;
1489 
1490 	error = xfs_finish_flags(mp);
1491 	if (error)
1492 		goto out_free_sb;
1493 
1494 	error = xfs_setup_devices(mp);
1495 	if (error)
1496 		goto out_free_sb;
1497 
1498 	/* V4 support is undergoing deprecation. */
1499 	if (!xfs_has_crc(mp)) {
1500 #ifdef CONFIG_XFS_SUPPORT_V4
1501 		xfs_warn_once(mp,
1502 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1503 #else
1504 		xfs_warn(mp,
1505 	"Deprecated V4 format (crc=0) not supported by kernel.");
1506 		error = -EINVAL;
1507 		goto out_free_sb;
1508 #endif
1509 	}
1510 
1511 	/* Filesystem claims it needs repair, so refuse the mount. */
1512 	if (xfs_has_needsrepair(mp)) {
1513 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1514 		error = -EFSCORRUPTED;
1515 		goto out_free_sb;
1516 	}
1517 
1518 	/*
1519 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1520 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1521 	 * we don't check them at all.
1522 	 */
1523 	if (mp->m_sb.sb_inprogress) {
1524 		xfs_warn(mp, "Offline file system operation in progress!");
1525 		error = -EFSCORRUPTED;
1526 		goto out_free_sb;
1527 	}
1528 
1529 	/*
1530 	 * Until this is fixed only page-sized or smaller data blocks work.
1531 	 */
1532 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1533 		xfs_warn(mp,
1534 		"File system with blocksize %d bytes. "
1535 		"Only pagesize (%ld) or less will currently work.",
1536 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1537 		error = -ENOSYS;
1538 		goto out_free_sb;
1539 	}
1540 
1541 	/* Ensure this filesystem fits in the page cache limits */
1542 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1543 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1544 		xfs_warn(mp,
1545 		"file system too large to be mounted on this system.");
1546 		error = -EFBIG;
1547 		goto out_free_sb;
1548 	}
1549 
1550 	/*
1551 	 * XFS block mappings use 54 bits to store the logical block offset.
1552 	 * This should suffice to handle the maximum file size that the VFS
1553 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1554 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1555 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1556 	 * to check this assertion.
1557 	 *
1558 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1559 	 * maximum pagecache offset in units of fs blocks.
1560 	 */
1561 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1562 		xfs_warn(mp,
1563 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1564 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1565 			 XFS_MAX_FILEOFF);
1566 		error = -EINVAL;
1567 		goto out_free_sb;
1568 	}
1569 
1570 	error = xfs_filestream_mount(mp);
1571 	if (error)
1572 		goto out_free_sb;
1573 
1574 	/*
1575 	 * we must configure the block size in the superblock before we run the
1576 	 * full mount process as the mount process can lookup and cache inodes.
1577 	 */
1578 	sb->s_magic = XFS_SUPER_MAGIC;
1579 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1580 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1581 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1582 	sb->s_max_links = XFS_MAXLINK;
1583 	sb->s_time_gran = 1;
1584 	if (xfs_has_bigtime(mp)) {
1585 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1586 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1587 	} else {
1588 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1589 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1590 	}
1591 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1592 	sb->s_iflags |= SB_I_CGROUPWB;
1593 
1594 	set_posix_acl_flag(sb);
1595 
1596 	/* version 5 superblocks support inode version counters. */
1597 	if (xfs_has_crc(mp))
1598 		sb->s_flags |= SB_I_VERSION;
1599 
1600 	if (xfs_has_dax_always(mp)) {
1601 		error = xfs_setup_dax_always(mp);
1602 		if (error)
1603 			goto out_filestream_unmount;
1604 	}
1605 
1606 	if (xfs_has_discard(mp)) {
1607 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1608 
1609 		if (!blk_queue_discard(q)) {
1610 			xfs_warn(mp, "mounting with \"discard\" option, but "
1611 					"the device does not support discard");
1612 			mp->m_features &= ~XFS_FEAT_DISCARD;
1613 		}
1614 	}
1615 
1616 	if (xfs_has_reflink(mp)) {
1617 		if (mp->m_sb.sb_rblocks) {
1618 			xfs_alert(mp,
1619 	"reflink not compatible with realtime device!");
1620 			error = -EINVAL;
1621 			goto out_filestream_unmount;
1622 		}
1623 
1624 		if (xfs_globals.always_cow) {
1625 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1626 			mp->m_always_cow = true;
1627 		}
1628 	}
1629 
1630 	if (xfs_has_rmapbt(mp) && mp->m_sb.sb_rblocks) {
1631 		xfs_alert(mp,
1632 	"reverse mapping btree not compatible with realtime device!");
1633 		error = -EINVAL;
1634 		goto out_filestream_unmount;
1635 	}
1636 
1637 	error = xfs_mountfs(mp);
1638 	if (error)
1639 		goto out_filestream_unmount;
1640 
1641 	root = igrab(VFS_I(mp->m_rootip));
1642 	if (!root) {
1643 		error = -ENOENT;
1644 		goto out_unmount;
1645 	}
1646 	sb->s_root = d_make_root(root);
1647 	if (!sb->s_root) {
1648 		error = -ENOMEM;
1649 		goto out_unmount;
1650 	}
1651 
1652 	return 0;
1653 
1654  out_filestream_unmount:
1655 	xfs_filestream_unmount(mp);
1656  out_free_sb:
1657 	xfs_freesb(mp);
1658  out_free_stats:
1659 	free_percpu(mp->m_stats.xs_stats);
1660  out_destroy_inodegc:
1661 	xfs_mount_list_del(mp);
1662 	xfs_inodegc_free_percpu(mp);
1663  out_destroy_counters:
1664 	xfs_destroy_percpu_counters(mp);
1665  out_destroy_workqueues:
1666 	xfs_destroy_mount_workqueues(mp);
1667  out_close_devices:
1668 	xfs_close_devices(mp);
1669  out_free_names:
1670 	sb->s_fs_info = NULL;
1671 	xfs_mount_free(mp);
1672 	return error;
1673 
1674  out_unmount:
1675 	xfs_filestream_unmount(mp);
1676 	xfs_unmountfs(mp);
1677 	goto out_free_sb;
1678 }
1679 
1680 static int
1681 xfs_fs_get_tree(
1682 	struct fs_context	*fc)
1683 {
1684 	return get_tree_bdev(fc, xfs_fs_fill_super);
1685 }
1686 
1687 static int
1688 xfs_remount_rw(
1689 	struct xfs_mount	*mp)
1690 {
1691 	struct xfs_sb		*sbp = &mp->m_sb;
1692 	int error;
1693 
1694 	if (xfs_has_norecovery(mp)) {
1695 		xfs_warn(mp,
1696 			"ro->rw transition prohibited on norecovery mount");
1697 		return -EINVAL;
1698 	}
1699 
1700 	if (xfs_sb_is_v5(sbp) &&
1701 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1702 		xfs_warn(mp,
1703 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1704 			(sbp->sb_features_ro_compat &
1705 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1706 		return -EINVAL;
1707 	}
1708 
1709 	clear_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1710 
1711 	/*
1712 	 * If this is the first remount to writeable state we might have some
1713 	 * superblock changes to update.
1714 	 */
1715 	if (mp->m_update_sb) {
1716 		error = xfs_sync_sb(mp, false);
1717 		if (error) {
1718 			xfs_warn(mp, "failed to write sb changes");
1719 			return error;
1720 		}
1721 		mp->m_update_sb = false;
1722 	}
1723 
1724 	/*
1725 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1726 	 * it is non-zero, otherwise go with the default.
1727 	 */
1728 	xfs_restore_resvblks(mp);
1729 	xfs_log_work_queue(mp);
1730 	xfs_blockgc_start(mp);
1731 
1732 	/* Create the per-AG metadata reservation pool .*/
1733 	error = xfs_fs_reserve_ag_blocks(mp);
1734 	if (error && error != -ENOSPC)
1735 		return error;
1736 
1737 	/* Re-enable the background inode inactivation worker. */
1738 	xfs_inodegc_start(mp);
1739 
1740 	return 0;
1741 }
1742 
1743 static int
1744 xfs_remount_ro(
1745 	struct xfs_mount	*mp)
1746 {
1747 	struct xfs_icwalk	icw = {
1748 		.icw_flags	= XFS_ICWALK_FLAG_SYNC,
1749 	};
1750 	int			error;
1751 
1752 	/*
1753 	 * Cancel background eofb scanning so it cannot race with the final
1754 	 * log force+buftarg wait and deadlock the remount.
1755 	 */
1756 	xfs_blockgc_stop(mp);
1757 
1758 	/*
1759 	 * Clear out all remaining COW staging extents and speculative post-EOF
1760 	 * preallocations so that we don't leave inodes requiring inactivation
1761 	 * cleanups during reclaim on a read-only mount.  We must process every
1762 	 * cached inode, so this requires a synchronous cache scan.
1763 	 */
1764 	error = xfs_blockgc_free_space(mp, &icw);
1765 	if (error) {
1766 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1767 		return error;
1768 	}
1769 
1770 	/*
1771 	 * Stop the inodegc background worker.  xfs_fs_reconfigure already
1772 	 * flushed all pending inodegc work when it sync'd the filesystem.
1773 	 * The VFS holds s_umount, so we know that inodes cannot enter
1774 	 * xfs_fs_destroy_inode during a remount operation.  In readonly mode
1775 	 * we send inodes straight to reclaim, so no inodes will be queued.
1776 	 */
1777 	xfs_inodegc_stop(mp);
1778 
1779 	/* Free the per-AG metadata reservation pool. */
1780 	error = xfs_fs_unreserve_ag_blocks(mp);
1781 	if (error) {
1782 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1783 		return error;
1784 	}
1785 
1786 	/*
1787 	 * Before we sync the metadata, we need to free up the reserve block
1788 	 * pool so that the used block count in the superblock on disk is
1789 	 * correct at the end of the remount. Stash the current* reserve pool
1790 	 * size so that if we get remounted rw, we can return it to the same
1791 	 * size.
1792 	 */
1793 	xfs_save_resvblks(mp);
1794 
1795 	xfs_log_clean(mp);
1796 	set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1797 
1798 	return 0;
1799 }
1800 
1801 /*
1802  * Logically we would return an error here to prevent users from believing
1803  * they might have changed mount options using remount which can't be changed.
1804  *
1805  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1806  * arguments in some cases so we can't blindly reject options, but have to
1807  * check for each specified option if it actually differs from the currently
1808  * set option and only reject it if that's the case.
1809  *
1810  * Until that is implemented we return success for every remount request, and
1811  * silently ignore all options that we can't actually change.
1812  */
1813 static int
1814 xfs_fs_reconfigure(
1815 	struct fs_context *fc)
1816 {
1817 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1818 	struct xfs_mount        *new_mp = fc->s_fs_info;
1819 	int			flags = fc->sb_flags;
1820 	int			error;
1821 
1822 	/* version 5 superblocks always support version counters. */
1823 	if (xfs_has_crc(mp))
1824 		fc->sb_flags |= SB_I_VERSION;
1825 
1826 	error = xfs_fs_validate_params(new_mp);
1827 	if (error)
1828 		return error;
1829 
1830 	sync_filesystem(mp->m_super);
1831 
1832 	/* inode32 -> inode64 */
1833 	if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
1834 		mp->m_features &= ~XFS_FEAT_SMALL_INUMS;
1835 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1836 	}
1837 
1838 	/* inode64 -> inode32 */
1839 	if (!xfs_has_small_inums(mp) && xfs_has_small_inums(new_mp)) {
1840 		mp->m_features |= XFS_FEAT_SMALL_INUMS;
1841 		mp->m_maxagi = xfs_set_inode_alloc(mp, mp->m_sb.sb_agcount);
1842 	}
1843 
1844 	/* ro -> rw */
1845 	if (xfs_is_readonly(mp) && !(flags & SB_RDONLY)) {
1846 		error = xfs_remount_rw(mp);
1847 		if (error)
1848 			return error;
1849 	}
1850 
1851 	/* rw -> ro */
1852 	if (!xfs_is_readonly(mp) && (flags & SB_RDONLY)) {
1853 		error = xfs_remount_ro(mp);
1854 		if (error)
1855 			return error;
1856 	}
1857 
1858 	return 0;
1859 }
1860 
1861 static void xfs_fs_free(
1862 	struct fs_context	*fc)
1863 {
1864 	struct xfs_mount	*mp = fc->s_fs_info;
1865 
1866 	/*
1867 	 * mp is stored in the fs_context when it is initialized.
1868 	 * mp is transferred to the superblock on a successful mount,
1869 	 * but if an error occurs before the transfer we have to free
1870 	 * it here.
1871 	 */
1872 	if (mp)
1873 		xfs_mount_free(mp);
1874 }
1875 
1876 static const struct fs_context_operations xfs_context_ops = {
1877 	.parse_param = xfs_fs_parse_param,
1878 	.get_tree    = xfs_fs_get_tree,
1879 	.reconfigure = xfs_fs_reconfigure,
1880 	.free        = xfs_fs_free,
1881 };
1882 
1883 static int xfs_init_fs_context(
1884 	struct fs_context	*fc)
1885 {
1886 	struct xfs_mount	*mp;
1887 
1888 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1889 	if (!mp)
1890 		return -ENOMEM;
1891 
1892 	spin_lock_init(&mp->m_sb_lock);
1893 	spin_lock_init(&mp->m_agirotor_lock);
1894 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1895 	spin_lock_init(&mp->m_perag_lock);
1896 	mutex_init(&mp->m_growlock);
1897 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1898 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1899 	mp->m_kobj.kobject.kset = xfs_kset;
1900 	/*
1901 	 * We don't create the finobt per-ag space reservation until after log
1902 	 * recovery, so we must set this to true so that an ifree transaction
1903 	 * started during log recovery will not depend on space reservations
1904 	 * for finobt expansion.
1905 	 */
1906 	mp->m_finobt_nores = true;
1907 
1908 	/*
1909 	 * These can be overridden by the mount option parsing.
1910 	 */
1911 	mp->m_logbufs = -1;
1912 	mp->m_logbsize = -1;
1913 	mp->m_allocsize_log = 16; /* 64k */
1914 
1915 	/*
1916 	 * Copy binary VFS mount flags we are interested in.
1917 	 */
1918 	if (fc->sb_flags & SB_RDONLY)
1919 		set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate);
1920 	if (fc->sb_flags & SB_DIRSYNC)
1921 		mp->m_features |= XFS_FEAT_DIRSYNC;
1922 	if (fc->sb_flags & SB_SYNCHRONOUS)
1923 		mp->m_features |= XFS_FEAT_WSYNC;
1924 
1925 	fc->s_fs_info = mp;
1926 	fc->ops = &xfs_context_ops;
1927 
1928 	return 0;
1929 }
1930 
1931 static struct file_system_type xfs_fs_type = {
1932 	.owner			= THIS_MODULE,
1933 	.name			= "xfs",
1934 	.init_fs_context	= xfs_init_fs_context,
1935 	.parameters		= xfs_fs_parameters,
1936 	.kill_sb		= kill_block_super,
1937 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1938 };
1939 MODULE_ALIAS_FS("xfs");
1940 
1941 STATIC int __init
1942 xfs_init_caches(void)
1943 {
1944 	int		error;
1945 
1946 	xfs_log_ticket_cache = kmem_cache_create("xfs_log_ticket",
1947 						sizeof(struct xlog_ticket),
1948 						0, 0, NULL);
1949 	if (!xfs_log_ticket_cache)
1950 		goto out;
1951 
1952 	error = xfs_btree_init_cur_caches();
1953 	if (error)
1954 		goto out_destroy_log_ticket_cache;
1955 
1956 	error = xfs_defer_init_item_caches();
1957 	if (error)
1958 		goto out_destroy_btree_cur_cache;
1959 
1960 	xfs_da_state_cache = kmem_cache_create("xfs_da_state",
1961 					      sizeof(struct xfs_da_state),
1962 					      0, 0, NULL);
1963 	if (!xfs_da_state_cache)
1964 		goto out_destroy_defer_item_cache;
1965 
1966 	xfs_ifork_cache = kmem_cache_create("xfs_ifork",
1967 					   sizeof(struct xfs_ifork),
1968 					   0, 0, NULL);
1969 	if (!xfs_ifork_cache)
1970 		goto out_destroy_da_state_cache;
1971 
1972 	xfs_trans_cache = kmem_cache_create("xfs_trans",
1973 					   sizeof(struct xfs_trans),
1974 					   0, 0, NULL);
1975 	if (!xfs_trans_cache)
1976 		goto out_destroy_ifork_cache;
1977 
1978 
1979 	/*
1980 	 * The size of the cache-allocated buf log item is the maximum
1981 	 * size possible under XFS.  This wastes a little bit of memory,
1982 	 * but it is much faster.
1983 	 */
1984 	xfs_buf_item_cache = kmem_cache_create("xfs_buf_item",
1985 					      sizeof(struct xfs_buf_log_item),
1986 					      0, 0, NULL);
1987 	if (!xfs_buf_item_cache)
1988 		goto out_destroy_trans_cache;
1989 
1990 	xfs_efd_cache = kmem_cache_create("xfs_efd_item",
1991 					(sizeof(struct xfs_efd_log_item) +
1992 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
1993 					sizeof(struct xfs_extent)),
1994 					0, 0, NULL);
1995 	if (!xfs_efd_cache)
1996 		goto out_destroy_buf_item_cache;
1997 
1998 	xfs_efi_cache = kmem_cache_create("xfs_efi_item",
1999 					 (sizeof(struct xfs_efi_log_item) +
2000 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
2001 					 sizeof(struct xfs_extent)),
2002 					 0, 0, NULL);
2003 	if (!xfs_efi_cache)
2004 		goto out_destroy_efd_cache;
2005 
2006 	xfs_inode_cache = kmem_cache_create("xfs_inode",
2007 					   sizeof(struct xfs_inode), 0,
2008 					   (SLAB_HWCACHE_ALIGN |
2009 					    SLAB_RECLAIM_ACCOUNT |
2010 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
2011 					   xfs_fs_inode_init_once);
2012 	if (!xfs_inode_cache)
2013 		goto out_destroy_efi_cache;
2014 
2015 	xfs_ili_cache = kmem_cache_create("xfs_ili",
2016 					 sizeof(struct xfs_inode_log_item), 0,
2017 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
2018 					 NULL);
2019 	if (!xfs_ili_cache)
2020 		goto out_destroy_inode_cache;
2021 
2022 	xfs_icreate_cache = kmem_cache_create("xfs_icr",
2023 					     sizeof(struct xfs_icreate_item),
2024 					     0, 0, NULL);
2025 	if (!xfs_icreate_cache)
2026 		goto out_destroy_ili_cache;
2027 
2028 	xfs_rud_cache = kmem_cache_create("xfs_rud_item",
2029 					 sizeof(struct xfs_rud_log_item),
2030 					 0, 0, NULL);
2031 	if (!xfs_rud_cache)
2032 		goto out_destroy_icreate_cache;
2033 
2034 	xfs_rui_cache = kmem_cache_create("xfs_rui_item",
2035 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
2036 			0, 0, NULL);
2037 	if (!xfs_rui_cache)
2038 		goto out_destroy_rud_cache;
2039 
2040 	xfs_cud_cache = kmem_cache_create("xfs_cud_item",
2041 					 sizeof(struct xfs_cud_log_item),
2042 					 0, 0, NULL);
2043 	if (!xfs_cud_cache)
2044 		goto out_destroy_rui_cache;
2045 
2046 	xfs_cui_cache = kmem_cache_create("xfs_cui_item",
2047 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2048 			0, 0, NULL);
2049 	if (!xfs_cui_cache)
2050 		goto out_destroy_cud_cache;
2051 
2052 	xfs_bud_cache = kmem_cache_create("xfs_bud_item",
2053 					 sizeof(struct xfs_bud_log_item),
2054 					 0, 0, NULL);
2055 	if (!xfs_bud_cache)
2056 		goto out_destroy_cui_cache;
2057 
2058 	xfs_bui_cache = kmem_cache_create("xfs_bui_item",
2059 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2060 			0, 0, NULL);
2061 	if (!xfs_bui_cache)
2062 		goto out_destroy_bud_cache;
2063 
2064 	return 0;
2065 
2066  out_destroy_bud_cache:
2067 	kmem_cache_destroy(xfs_bud_cache);
2068  out_destroy_cui_cache:
2069 	kmem_cache_destroy(xfs_cui_cache);
2070  out_destroy_cud_cache:
2071 	kmem_cache_destroy(xfs_cud_cache);
2072  out_destroy_rui_cache:
2073 	kmem_cache_destroy(xfs_rui_cache);
2074  out_destroy_rud_cache:
2075 	kmem_cache_destroy(xfs_rud_cache);
2076  out_destroy_icreate_cache:
2077 	kmem_cache_destroy(xfs_icreate_cache);
2078  out_destroy_ili_cache:
2079 	kmem_cache_destroy(xfs_ili_cache);
2080  out_destroy_inode_cache:
2081 	kmem_cache_destroy(xfs_inode_cache);
2082  out_destroy_efi_cache:
2083 	kmem_cache_destroy(xfs_efi_cache);
2084  out_destroy_efd_cache:
2085 	kmem_cache_destroy(xfs_efd_cache);
2086  out_destroy_buf_item_cache:
2087 	kmem_cache_destroy(xfs_buf_item_cache);
2088  out_destroy_trans_cache:
2089 	kmem_cache_destroy(xfs_trans_cache);
2090  out_destroy_ifork_cache:
2091 	kmem_cache_destroy(xfs_ifork_cache);
2092  out_destroy_da_state_cache:
2093 	kmem_cache_destroy(xfs_da_state_cache);
2094  out_destroy_defer_item_cache:
2095 	xfs_defer_destroy_item_caches();
2096  out_destroy_btree_cur_cache:
2097 	xfs_btree_destroy_cur_caches();
2098  out_destroy_log_ticket_cache:
2099 	kmem_cache_destroy(xfs_log_ticket_cache);
2100  out:
2101 	return -ENOMEM;
2102 }
2103 
2104 STATIC void
2105 xfs_destroy_caches(void)
2106 {
2107 	/*
2108 	 * Make sure all delayed rcu free are flushed before we
2109 	 * destroy caches.
2110 	 */
2111 	rcu_barrier();
2112 	kmem_cache_destroy(xfs_bui_cache);
2113 	kmem_cache_destroy(xfs_bud_cache);
2114 	kmem_cache_destroy(xfs_cui_cache);
2115 	kmem_cache_destroy(xfs_cud_cache);
2116 	kmem_cache_destroy(xfs_rui_cache);
2117 	kmem_cache_destroy(xfs_rud_cache);
2118 	kmem_cache_destroy(xfs_icreate_cache);
2119 	kmem_cache_destroy(xfs_ili_cache);
2120 	kmem_cache_destroy(xfs_inode_cache);
2121 	kmem_cache_destroy(xfs_efi_cache);
2122 	kmem_cache_destroy(xfs_efd_cache);
2123 	kmem_cache_destroy(xfs_buf_item_cache);
2124 	kmem_cache_destroy(xfs_trans_cache);
2125 	kmem_cache_destroy(xfs_ifork_cache);
2126 	kmem_cache_destroy(xfs_da_state_cache);
2127 	xfs_defer_destroy_item_caches();
2128 	xfs_btree_destroy_cur_caches();
2129 	kmem_cache_destroy(xfs_log_ticket_cache);
2130 }
2131 
2132 STATIC int __init
2133 xfs_init_workqueues(void)
2134 {
2135 	/*
2136 	 * The allocation workqueue can be used in memory reclaim situations
2137 	 * (writepage path), and parallelism is only limited by the number of
2138 	 * AGs in all the filesystems mounted. Hence use the default large
2139 	 * max_active value for this workqueue.
2140 	 */
2141 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2142 			XFS_WQFLAGS(WQ_MEM_RECLAIM | WQ_FREEZABLE), 0);
2143 	if (!xfs_alloc_wq)
2144 		return -ENOMEM;
2145 
2146 	xfs_discard_wq = alloc_workqueue("xfsdiscard", XFS_WQFLAGS(WQ_UNBOUND),
2147 			0);
2148 	if (!xfs_discard_wq)
2149 		goto out_free_alloc_wq;
2150 
2151 	return 0;
2152 out_free_alloc_wq:
2153 	destroy_workqueue(xfs_alloc_wq);
2154 	return -ENOMEM;
2155 }
2156 
2157 STATIC void
2158 xfs_destroy_workqueues(void)
2159 {
2160 	destroy_workqueue(xfs_discard_wq);
2161 	destroy_workqueue(xfs_alloc_wq);
2162 }
2163 
2164 #ifdef CONFIG_HOTPLUG_CPU
2165 static int
2166 xfs_cpu_dead(
2167 	unsigned int		cpu)
2168 {
2169 	struct xfs_mount	*mp, *n;
2170 
2171 	spin_lock(&xfs_mount_list_lock);
2172 	list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
2173 		spin_unlock(&xfs_mount_list_lock);
2174 		xfs_inodegc_cpu_dead(mp, cpu);
2175 		spin_lock(&xfs_mount_list_lock);
2176 	}
2177 	spin_unlock(&xfs_mount_list_lock);
2178 	return 0;
2179 }
2180 
2181 static int __init
2182 xfs_cpu_hotplug_init(void)
2183 {
2184 	int	error;
2185 
2186 	error = cpuhp_setup_state_nocalls(CPUHP_XFS_DEAD, "xfs:dead", NULL,
2187 			xfs_cpu_dead);
2188 	if (error < 0)
2189 		xfs_alert(NULL,
2190 "Failed to initialise CPU hotplug, error %d. XFS is non-functional.",
2191 			error);
2192 	return error;
2193 }
2194 
2195 static void
2196 xfs_cpu_hotplug_destroy(void)
2197 {
2198 	cpuhp_remove_state_nocalls(CPUHP_XFS_DEAD);
2199 }
2200 
2201 #else /* !CONFIG_HOTPLUG_CPU */
2202 static inline int xfs_cpu_hotplug_init(void) { return 0; }
2203 static inline void xfs_cpu_hotplug_destroy(void) {}
2204 #endif
2205 
2206 STATIC int __init
2207 init_xfs_fs(void)
2208 {
2209 	int			error;
2210 
2211 	xfs_check_ondisk_structs();
2212 
2213 	printk(KERN_INFO XFS_VERSION_STRING " with "
2214 			 XFS_BUILD_OPTIONS " enabled\n");
2215 
2216 	xfs_dir_startup();
2217 
2218 	error = xfs_cpu_hotplug_init();
2219 	if (error)
2220 		goto out;
2221 
2222 	error = xfs_init_caches();
2223 	if (error)
2224 		goto out_destroy_hp;
2225 
2226 	error = xfs_init_workqueues();
2227 	if (error)
2228 		goto out_destroy_caches;
2229 
2230 	error = xfs_mru_cache_init();
2231 	if (error)
2232 		goto out_destroy_wq;
2233 
2234 	error = xfs_buf_init();
2235 	if (error)
2236 		goto out_mru_cache_uninit;
2237 
2238 	error = xfs_init_procfs();
2239 	if (error)
2240 		goto out_buf_terminate;
2241 
2242 	error = xfs_sysctl_register();
2243 	if (error)
2244 		goto out_cleanup_procfs;
2245 
2246 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2247 	if (!xfs_kset) {
2248 		error = -ENOMEM;
2249 		goto out_sysctl_unregister;
2250 	}
2251 
2252 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2253 
2254 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2255 	if (!xfsstats.xs_stats) {
2256 		error = -ENOMEM;
2257 		goto out_kset_unregister;
2258 	}
2259 
2260 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2261 			       "stats");
2262 	if (error)
2263 		goto out_free_stats;
2264 
2265 #ifdef DEBUG
2266 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2267 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2268 	if (error)
2269 		goto out_remove_stats_kobj;
2270 #endif
2271 
2272 	error = xfs_qm_init();
2273 	if (error)
2274 		goto out_remove_dbg_kobj;
2275 
2276 	error = register_filesystem(&xfs_fs_type);
2277 	if (error)
2278 		goto out_qm_exit;
2279 	return 0;
2280 
2281  out_qm_exit:
2282 	xfs_qm_exit();
2283  out_remove_dbg_kobj:
2284 #ifdef DEBUG
2285 	xfs_sysfs_del(&xfs_dbg_kobj);
2286  out_remove_stats_kobj:
2287 #endif
2288 	xfs_sysfs_del(&xfsstats.xs_kobj);
2289  out_free_stats:
2290 	free_percpu(xfsstats.xs_stats);
2291  out_kset_unregister:
2292 	kset_unregister(xfs_kset);
2293  out_sysctl_unregister:
2294 	xfs_sysctl_unregister();
2295  out_cleanup_procfs:
2296 	xfs_cleanup_procfs();
2297  out_buf_terminate:
2298 	xfs_buf_terminate();
2299  out_mru_cache_uninit:
2300 	xfs_mru_cache_uninit();
2301  out_destroy_wq:
2302 	xfs_destroy_workqueues();
2303  out_destroy_caches:
2304 	xfs_destroy_caches();
2305  out_destroy_hp:
2306 	xfs_cpu_hotplug_destroy();
2307  out:
2308 	return error;
2309 }
2310 
2311 STATIC void __exit
2312 exit_xfs_fs(void)
2313 {
2314 	xfs_qm_exit();
2315 	unregister_filesystem(&xfs_fs_type);
2316 #ifdef DEBUG
2317 	xfs_sysfs_del(&xfs_dbg_kobj);
2318 #endif
2319 	xfs_sysfs_del(&xfsstats.xs_kobj);
2320 	free_percpu(xfsstats.xs_stats);
2321 	kset_unregister(xfs_kset);
2322 	xfs_sysctl_unregister();
2323 	xfs_cleanup_procfs();
2324 	xfs_buf_terminate();
2325 	xfs_mru_cache_uninit();
2326 	xfs_destroy_workqueues();
2327 	xfs_destroy_caches();
2328 	xfs_uuid_table_free();
2329 	xfs_cpu_hotplug_destroy();
2330 }
2331 
2332 module_init(init_xfs_fs);
2333 module_exit(exit_xfs_fs);
2334 
2335 MODULE_AUTHOR("Silicon Graphics, Inc.");
2336 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2337 MODULE_LICENSE("GPL");
2338