xref: /openbmc/linux/fs/xfs/xfs_super.c (revision 84b102f5)
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 
39 #include <linux/magic.h>
40 #include <linux/fs_context.h>
41 #include <linux/fs_parser.h>
42 
43 static const struct super_operations xfs_super_operations;
44 
45 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
46 #ifdef DEBUG
47 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
48 #endif
49 
50 enum xfs_dax_mode {
51 	XFS_DAX_INODE = 0,
52 	XFS_DAX_ALWAYS = 1,
53 	XFS_DAX_NEVER = 2,
54 };
55 
56 static void
57 xfs_mount_set_dax_mode(
58 	struct xfs_mount	*mp,
59 	enum xfs_dax_mode	mode)
60 {
61 	switch (mode) {
62 	case XFS_DAX_INODE:
63 		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
64 		break;
65 	case XFS_DAX_ALWAYS:
66 		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
67 		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
68 		break;
69 	case XFS_DAX_NEVER:
70 		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
71 		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
72 		break;
73 	}
74 }
75 
76 static const struct constant_table dax_param_enums[] = {
77 	{"inode",	XFS_DAX_INODE },
78 	{"always",	XFS_DAX_ALWAYS },
79 	{"never",	XFS_DAX_NEVER },
80 	{}
81 };
82 
83 /*
84  * Table driven mount option parser.
85  */
86 enum {
87 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
88 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
89 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
90 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
91 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
92 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
93 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
94 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
95 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
96 };
97 
98 static const struct fs_parameter_spec xfs_fs_parameters[] = {
99 	fsparam_u32("logbufs",		Opt_logbufs),
100 	fsparam_string("logbsize",	Opt_logbsize),
101 	fsparam_string("logdev",	Opt_logdev),
102 	fsparam_string("rtdev",		Opt_rtdev),
103 	fsparam_flag("wsync",		Opt_wsync),
104 	fsparam_flag("noalign",		Opt_noalign),
105 	fsparam_flag("swalloc",		Opt_swalloc),
106 	fsparam_u32("sunit",		Opt_sunit),
107 	fsparam_u32("swidth",		Opt_swidth),
108 	fsparam_flag("nouuid",		Opt_nouuid),
109 	fsparam_flag("grpid",		Opt_grpid),
110 	fsparam_flag("nogrpid",		Opt_nogrpid),
111 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
112 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
113 	fsparam_string("allocsize",	Opt_allocsize),
114 	fsparam_flag("norecovery",	Opt_norecovery),
115 	fsparam_flag("inode64",		Opt_inode64),
116 	fsparam_flag("inode32",		Opt_inode32),
117 	fsparam_flag("ikeep",		Opt_ikeep),
118 	fsparam_flag("noikeep",		Opt_noikeep),
119 	fsparam_flag("largeio",		Opt_largeio),
120 	fsparam_flag("nolargeio",	Opt_nolargeio),
121 	fsparam_flag("attr2",		Opt_attr2),
122 	fsparam_flag("noattr2",		Opt_noattr2),
123 	fsparam_flag("filestreams",	Opt_filestreams),
124 	fsparam_flag("quota",		Opt_quota),
125 	fsparam_flag("noquota",		Opt_noquota),
126 	fsparam_flag("usrquota",	Opt_usrquota),
127 	fsparam_flag("grpquota",	Opt_grpquota),
128 	fsparam_flag("prjquota",	Opt_prjquota),
129 	fsparam_flag("uquota",		Opt_uquota),
130 	fsparam_flag("gquota",		Opt_gquota),
131 	fsparam_flag("pquota",		Opt_pquota),
132 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
133 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
134 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
135 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
136 	fsparam_flag("discard",		Opt_discard),
137 	fsparam_flag("nodiscard",	Opt_nodiscard),
138 	fsparam_flag("dax",		Opt_dax),
139 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
140 	{}
141 };
142 
143 struct proc_xfs_info {
144 	uint64_t	flag;
145 	char		*str;
146 };
147 
148 static int
149 xfs_fs_show_options(
150 	struct seq_file		*m,
151 	struct dentry		*root)
152 {
153 	static struct proc_xfs_info xfs_info_set[] = {
154 		/* the few simple ones we can get from the mount struct */
155 		{ XFS_MOUNT_IKEEP,		",ikeep" },
156 		{ XFS_MOUNT_WSYNC,		",wsync" },
157 		{ XFS_MOUNT_NOALIGN,		",noalign" },
158 		{ XFS_MOUNT_SWALLOC,		",swalloc" },
159 		{ XFS_MOUNT_NOUUID,		",nouuid" },
160 		{ XFS_MOUNT_NORECOVERY,		",norecovery" },
161 		{ XFS_MOUNT_ATTR2,		",attr2" },
162 		{ XFS_MOUNT_FILESTREAMS,	",filestreams" },
163 		{ XFS_MOUNT_GRPID,		",grpid" },
164 		{ XFS_MOUNT_DISCARD,		",discard" },
165 		{ XFS_MOUNT_LARGEIO,		",largeio" },
166 		{ XFS_MOUNT_DAX_ALWAYS,		",dax=always" },
167 		{ XFS_MOUNT_DAX_NEVER,		",dax=never" },
168 		{ 0, NULL }
169 	};
170 	struct xfs_mount	*mp = XFS_M(root->d_sb);
171 	struct proc_xfs_info	*xfs_infop;
172 
173 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
174 		if (mp->m_flags & xfs_infop->flag)
175 			seq_puts(m, xfs_infop->str);
176 	}
177 
178 	seq_printf(m, ",inode%d",
179 		(mp->m_flags & XFS_MOUNT_SMALL_INUMS) ? 32 : 64);
180 
181 	if (mp->m_flags & XFS_MOUNT_ALLOCSIZE)
182 		seq_printf(m, ",allocsize=%dk",
183 			   (1 << mp->m_allocsize_log) >> 10);
184 
185 	if (mp->m_logbufs > 0)
186 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
187 	if (mp->m_logbsize > 0)
188 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
189 
190 	if (mp->m_logname)
191 		seq_show_option(m, "logdev", mp->m_logname);
192 	if (mp->m_rtname)
193 		seq_show_option(m, "rtdev", mp->m_rtname);
194 
195 	if (mp->m_dalign > 0)
196 		seq_printf(m, ",sunit=%d",
197 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
198 	if (mp->m_swidth > 0)
199 		seq_printf(m, ",swidth=%d",
200 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
201 
202 	if (mp->m_qflags & XFS_UQUOTA_ACCT) {
203 		if (mp->m_qflags & XFS_UQUOTA_ENFD)
204 			seq_puts(m, ",usrquota");
205 		else
206 			seq_puts(m, ",uqnoenforce");
207 	}
208 
209 	if (mp->m_qflags & XFS_PQUOTA_ACCT) {
210 		if (mp->m_qflags & XFS_PQUOTA_ENFD)
211 			seq_puts(m, ",prjquota");
212 		else
213 			seq_puts(m, ",pqnoenforce");
214 	}
215 	if (mp->m_qflags & XFS_GQUOTA_ACCT) {
216 		if (mp->m_qflags & XFS_GQUOTA_ENFD)
217 			seq_puts(m, ",grpquota");
218 		else
219 			seq_puts(m, ",gqnoenforce");
220 	}
221 
222 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
223 		seq_puts(m, ",noquota");
224 
225 	return 0;
226 }
227 
228 /*
229  * Set parameters for inode allocation heuristics, taking into account
230  * filesystem size and inode32/inode64 mount options; i.e. specifically
231  * whether or not XFS_MOUNT_SMALL_INUMS is set.
232  *
233  * Inode allocation patterns are altered only if inode32 is requested
234  * (XFS_MOUNT_SMALL_INUMS), and the filesystem is sufficiently large.
235  * If altered, XFS_MOUNT_32BITINODES is set as well.
236  *
237  * An agcount independent of that in the mount structure is provided
238  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
239  * to the potentially higher ag count.
240  *
241  * Returns the maximum AG index which may contain inodes.
242  */
243 xfs_agnumber_t
244 xfs_set_inode_alloc(
245 	struct xfs_mount *mp,
246 	xfs_agnumber_t	agcount)
247 {
248 	xfs_agnumber_t	index;
249 	xfs_agnumber_t	maxagi = 0;
250 	xfs_sb_t	*sbp = &mp->m_sb;
251 	xfs_agnumber_t	max_metadata;
252 	xfs_agino_t	agino;
253 	xfs_ino_t	ino;
254 
255 	/*
256 	 * Calculate how much should be reserved for inodes to meet
257 	 * the max inode percentage.  Used only for inode32.
258 	 */
259 	if (M_IGEO(mp)->maxicount) {
260 		uint64_t	icount;
261 
262 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
263 		do_div(icount, 100);
264 		icount += sbp->sb_agblocks - 1;
265 		do_div(icount, sbp->sb_agblocks);
266 		max_metadata = icount;
267 	} else {
268 		max_metadata = agcount;
269 	}
270 
271 	/* Get the last possible inode in the filesystem */
272 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
273 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
274 
275 	/*
276 	 * If user asked for no more than 32-bit inodes, and the fs is
277 	 * sufficiently large, set XFS_MOUNT_32BITINODES if we must alter
278 	 * the allocator to accommodate the request.
279 	 */
280 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > XFS_MAXINUMBER_32)
281 		mp->m_flags |= XFS_MOUNT_32BITINODES;
282 	else
283 		mp->m_flags &= ~XFS_MOUNT_32BITINODES;
284 
285 	for (index = 0; index < agcount; index++) {
286 		struct xfs_perag	*pag;
287 
288 		ino = XFS_AGINO_TO_INO(mp, index, agino);
289 
290 		pag = xfs_perag_get(mp, index);
291 
292 		if (mp->m_flags & XFS_MOUNT_32BITINODES) {
293 			if (ino > XFS_MAXINUMBER_32) {
294 				pag->pagi_inodeok = 0;
295 				pag->pagf_metadata = 0;
296 			} else {
297 				pag->pagi_inodeok = 1;
298 				maxagi++;
299 				if (index < max_metadata)
300 					pag->pagf_metadata = 1;
301 				else
302 					pag->pagf_metadata = 0;
303 			}
304 		} else {
305 			pag->pagi_inodeok = 1;
306 			pag->pagf_metadata = 0;
307 		}
308 
309 		xfs_perag_put(pag);
310 	}
311 
312 	return (mp->m_flags & XFS_MOUNT_32BITINODES) ? maxagi : agcount;
313 }
314 
315 STATIC int
316 xfs_blkdev_get(
317 	xfs_mount_t		*mp,
318 	const char		*name,
319 	struct block_device	**bdevp)
320 {
321 	int			error = 0;
322 
323 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
324 				    mp);
325 	if (IS_ERR(*bdevp)) {
326 		error = PTR_ERR(*bdevp);
327 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
328 	}
329 
330 	return error;
331 }
332 
333 STATIC void
334 xfs_blkdev_put(
335 	struct block_device	*bdev)
336 {
337 	if (bdev)
338 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
339 }
340 
341 void
342 xfs_blkdev_issue_flush(
343 	xfs_buftarg_t		*buftarg)
344 {
345 	blkdev_issue_flush(buftarg->bt_bdev, GFP_NOFS);
346 }
347 
348 STATIC void
349 xfs_close_devices(
350 	struct xfs_mount	*mp)
351 {
352 	struct dax_device *dax_ddev = mp->m_ddev_targp->bt_daxdev;
353 
354 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
355 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
356 		struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev;
357 
358 		xfs_free_buftarg(mp->m_logdev_targp);
359 		xfs_blkdev_put(logdev);
360 		fs_put_dax(dax_logdev);
361 	}
362 	if (mp->m_rtdev_targp) {
363 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
364 		struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev;
365 
366 		xfs_free_buftarg(mp->m_rtdev_targp);
367 		xfs_blkdev_put(rtdev);
368 		fs_put_dax(dax_rtdev);
369 	}
370 	xfs_free_buftarg(mp->m_ddev_targp);
371 	fs_put_dax(dax_ddev);
372 }
373 
374 /*
375  * The file system configurations are:
376  *	(1) device (partition) with data and internal log
377  *	(2) logical volume with data and log subvolumes.
378  *	(3) logical volume with data, log, and realtime subvolumes.
379  *
380  * We only have to handle opening the log and realtime volumes here if
381  * they are present.  The data subvolume has already been opened by
382  * get_sb_bdev() and is stored in sb->s_bdev.
383  */
384 STATIC int
385 xfs_open_devices(
386 	struct xfs_mount	*mp)
387 {
388 	struct block_device	*ddev = mp->m_super->s_bdev;
389 	struct dax_device	*dax_ddev = fs_dax_get_by_bdev(ddev);
390 	struct dax_device	*dax_logdev = NULL, *dax_rtdev = NULL;
391 	struct block_device	*logdev = NULL, *rtdev = NULL;
392 	int			error;
393 
394 	/*
395 	 * Open real time and log devices - order is important.
396 	 */
397 	if (mp->m_logname) {
398 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
399 		if (error)
400 			goto out;
401 		dax_logdev = fs_dax_get_by_bdev(logdev);
402 	}
403 
404 	if (mp->m_rtname) {
405 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
406 		if (error)
407 			goto out_close_logdev;
408 
409 		if (rtdev == ddev || rtdev == logdev) {
410 			xfs_warn(mp,
411 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
412 			error = -EINVAL;
413 			goto out_close_rtdev;
414 		}
415 		dax_rtdev = fs_dax_get_by_bdev(rtdev);
416 	}
417 
418 	/*
419 	 * Setup xfs_mount buffer target pointers
420 	 */
421 	error = -ENOMEM;
422 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev);
423 	if (!mp->m_ddev_targp)
424 		goto out_close_rtdev;
425 
426 	if (rtdev) {
427 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev);
428 		if (!mp->m_rtdev_targp)
429 			goto out_free_ddev_targ;
430 	}
431 
432 	if (logdev && logdev != ddev) {
433 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev);
434 		if (!mp->m_logdev_targp)
435 			goto out_free_rtdev_targ;
436 	} else {
437 		mp->m_logdev_targp = mp->m_ddev_targp;
438 	}
439 
440 	return 0;
441 
442  out_free_rtdev_targ:
443 	if (mp->m_rtdev_targp)
444 		xfs_free_buftarg(mp->m_rtdev_targp);
445  out_free_ddev_targ:
446 	xfs_free_buftarg(mp->m_ddev_targp);
447  out_close_rtdev:
448 	xfs_blkdev_put(rtdev);
449 	fs_put_dax(dax_rtdev);
450  out_close_logdev:
451 	if (logdev && logdev != ddev) {
452 		xfs_blkdev_put(logdev);
453 		fs_put_dax(dax_logdev);
454 	}
455  out:
456 	fs_put_dax(dax_ddev);
457 	return error;
458 }
459 
460 /*
461  * Setup xfs_mount buffer target pointers based on superblock
462  */
463 STATIC int
464 xfs_setup_devices(
465 	struct xfs_mount	*mp)
466 {
467 	int			error;
468 
469 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
470 	if (error)
471 		return error;
472 
473 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
474 		unsigned int	log_sector_size = BBSIZE;
475 
476 		if (xfs_sb_version_hassector(&mp->m_sb))
477 			log_sector_size = mp->m_sb.sb_logsectsize;
478 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
479 					    log_sector_size);
480 		if (error)
481 			return error;
482 	}
483 	if (mp->m_rtdev_targp) {
484 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
485 					    mp->m_sb.sb_sectsize);
486 		if (error)
487 			return error;
488 	}
489 
490 	return 0;
491 }
492 
493 STATIC int
494 xfs_init_mount_workqueues(
495 	struct xfs_mount	*mp)
496 {
497 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
498 			WQ_MEM_RECLAIM|WQ_FREEZABLE, 1, mp->m_super->s_id);
499 	if (!mp->m_buf_workqueue)
500 		goto out;
501 
502 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
503 			WQ_MEM_RECLAIM|WQ_FREEZABLE, 0, mp->m_super->s_id);
504 	if (!mp->m_unwritten_workqueue)
505 		goto out_destroy_buf;
506 
507 	mp->m_cil_workqueue = alloc_workqueue("xfs-cil/%s",
508 			WQ_MEM_RECLAIM | WQ_FREEZABLE | WQ_UNBOUND,
509 			0, mp->m_super->s_id);
510 	if (!mp->m_cil_workqueue)
511 		goto out_destroy_unwritten;
512 
513 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
514 			WQ_MEM_RECLAIM|WQ_FREEZABLE, 0, mp->m_super->s_id);
515 	if (!mp->m_reclaim_workqueue)
516 		goto out_destroy_cil;
517 
518 	mp->m_eofblocks_workqueue = alloc_workqueue("xfs-eofblocks/%s",
519 			WQ_MEM_RECLAIM|WQ_FREEZABLE, 0, mp->m_super->s_id);
520 	if (!mp->m_eofblocks_workqueue)
521 		goto out_destroy_reclaim;
522 
523 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s", WQ_FREEZABLE, 0,
524 					       mp->m_super->s_id);
525 	if (!mp->m_sync_workqueue)
526 		goto out_destroy_eofb;
527 
528 	return 0;
529 
530 out_destroy_eofb:
531 	destroy_workqueue(mp->m_eofblocks_workqueue);
532 out_destroy_reclaim:
533 	destroy_workqueue(mp->m_reclaim_workqueue);
534 out_destroy_cil:
535 	destroy_workqueue(mp->m_cil_workqueue);
536 out_destroy_unwritten:
537 	destroy_workqueue(mp->m_unwritten_workqueue);
538 out_destroy_buf:
539 	destroy_workqueue(mp->m_buf_workqueue);
540 out:
541 	return -ENOMEM;
542 }
543 
544 STATIC void
545 xfs_destroy_mount_workqueues(
546 	struct xfs_mount	*mp)
547 {
548 	destroy_workqueue(mp->m_sync_workqueue);
549 	destroy_workqueue(mp->m_eofblocks_workqueue);
550 	destroy_workqueue(mp->m_reclaim_workqueue);
551 	destroy_workqueue(mp->m_cil_workqueue);
552 	destroy_workqueue(mp->m_unwritten_workqueue);
553 	destroy_workqueue(mp->m_buf_workqueue);
554 }
555 
556 static void
557 xfs_flush_inodes_worker(
558 	struct work_struct	*work)
559 {
560 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
561 						   m_flush_inodes_work);
562 	struct super_block	*sb = mp->m_super;
563 
564 	if (down_read_trylock(&sb->s_umount)) {
565 		sync_inodes_sb(sb);
566 		up_read(&sb->s_umount);
567 	}
568 }
569 
570 /*
571  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
572  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
573  * for IO to complete so that we effectively throttle multiple callers to the
574  * rate at which IO is completing.
575  */
576 void
577 xfs_flush_inodes(
578 	struct xfs_mount	*mp)
579 {
580 	/*
581 	 * If flush_work() returns true then that means we waited for a flush
582 	 * which was already in progress.  Don't bother running another scan.
583 	 */
584 	if (flush_work(&mp->m_flush_inodes_work))
585 		return;
586 
587 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
588 	flush_work(&mp->m_flush_inodes_work);
589 }
590 
591 /* Catch misguided souls that try to use this interface on XFS */
592 STATIC struct inode *
593 xfs_fs_alloc_inode(
594 	struct super_block	*sb)
595 {
596 	BUG();
597 	return NULL;
598 }
599 
600 #ifdef DEBUG
601 static void
602 xfs_check_delalloc(
603 	struct xfs_inode	*ip,
604 	int			whichfork)
605 {
606 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
607 	struct xfs_bmbt_irec	got;
608 	struct xfs_iext_cursor	icur;
609 
610 	if (!ifp || !xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got))
611 		return;
612 	do {
613 		if (isnullstartblock(got.br_startblock)) {
614 			xfs_warn(ip->i_mount,
615 	"ino %llx %s fork has delalloc extent at [0x%llx:0x%llx]",
616 				ip->i_ino,
617 				whichfork == XFS_DATA_FORK ? "data" : "cow",
618 				got.br_startoff, got.br_blockcount);
619 		}
620 	} while (xfs_iext_next_extent(ifp, &icur, &got));
621 }
622 #else
623 #define xfs_check_delalloc(ip, whichfork)	do { } while (0)
624 #endif
625 
626 /*
627  * Now that the generic code is guaranteed not to be accessing
628  * the linux inode, we can inactivate and reclaim the inode.
629  */
630 STATIC void
631 xfs_fs_destroy_inode(
632 	struct inode		*inode)
633 {
634 	struct xfs_inode	*ip = XFS_I(inode);
635 
636 	trace_xfs_destroy_inode(ip);
637 
638 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
639 	XFS_STATS_INC(ip->i_mount, vn_rele);
640 	XFS_STATS_INC(ip->i_mount, vn_remove);
641 
642 	xfs_inactive(ip);
643 
644 	if (!XFS_FORCED_SHUTDOWN(ip->i_mount) && ip->i_delayed_blks) {
645 		xfs_check_delalloc(ip, XFS_DATA_FORK);
646 		xfs_check_delalloc(ip, XFS_COW_FORK);
647 		ASSERT(0);
648 	}
649 
650 	XFS_STATS_INC(ip->i_mount, vn_reclaim);
651 
652 	/*
653 	 * We should never get here with one of the reclaim flags already set.
654 	 */
655 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIMABLE));
656 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIM));
657 
658 	/*
659 	 * We always use background reclaim here because even if the inode is
660 	 * clean, it still may be under IO and hence we have wait for IO
661 	 * completion to occur before we can reclaim the inode. The background
662 	 * reclaim path handles this more efficiently than we can here, so
663 	 * simply let background reclaim tear down all inodes.
664 	 */
665 	xfs_inode_set_reclaim_tag(ip);
666 }
667 
668 static void
669 xfs_fs_dirty_inode(
670 	struct inode			*inode,
671 	int				flag)
672 {
673 	struct xfs_inode		*ip = XFS_I(inode);
674 	struct xfs_mount		*mp = ip->i_mount;
675 	struct xfs_trans		*tp;
676 
677 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
678 		return;
679 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
680 		return;
681 
682 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
683 		return;
684 	xfs_ilock(ip, XFS_ILOCK_EXCL);
685 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
686 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
687 	xfs_trans_commit(tp);
688 }
689 
690 /*
691  * Slab object creation initialisation for the XFS inode.
692  * This covers only the idempotent fields in the XFS inode;
693  * all other fields need to be initialised on allocation
694  * from the slab. This avoids the need to repeatedly initialise
695  * fields in the xfs inode that left in the initialise state
696  * when freeing the inode.
697  */
698 STATIC void
699 xfs_fs_inode_init_once(
700 	void			*inode)
701 {
702 	struct xfs_inode	*ip = inode;
703 
704 	memset(ip, 0, sizeof(struct xfs_inode));
705 
706 	/* vfs inode */
707 	inode_init_once(VFS_I(ip));
708 
709 	/* xfs inode */
710 	atomic_set(&ip->i_pincount, 0);
711 	spin_lock_init(&ip->i_flags_lock);
712 
713 	mrlock_init(&ip->i_mmaplock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
714 		     "xfsino", ip->i_ino);
715 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
716 		     "xfsino", ip->i_ino);
717 }
718 
719 /*
720  * We do an unlocked check for XFS_IDONTCACHE here because we are already
721  * serialised against cache hits here via the inode->i_lock and igrab() in
722  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
723  * racing with us, and it avoids needing to grab a spinlock here for every inode
724  * we drop the final reference on.
725  */
726 STATIC int
727 xfs_fs_drop_inode(
728 	struct inode		*inode)
729 {
730 	struct xfs_inode	*ip = XFS_I(inode);
731 
732 	/*
733 	 * If this unlinked inode is in the middle of recovery, don't
734 	 * drop the inode just yet; log recovery will take care of
735 	 * that.  See the comment for this inode flag.
736 	 */
737 	if (ip->i_flags & XFS_IRECOVERY) {
738 		ASSERT(ip->i_mount->m_log->l_flags & XLOG_RECOVERY_NEEDED);
739 		return 0;
740 	}
741 
742 	return generic_drop_inode(inode);
743 }
744 
745 static void
746 xfs_mount_free(
747 	struct xfs_mount	*mp)
748 {
749 	kfree(mp->m_rtname);
750 	kfree(mp->m_logname);
751 	kmem_free(mp);
752 }
753 
754 STATIC int
755 xfs_fs_sync_fs(
756 	struct super_block	*sb,
757 	int			wait)
758 {
759 	struct xfs_mount	*mp = XFS_M(sb);
760 
761 	/*
762 	 * Doing anything during the async pass would be counterproductive.
763 	 */
764 	if (!wait)
765 		return 0;
766 
767 	xfs_log_force(mp, XFS_LOG_SYNC);
768 	if (laptop_mode) {
769 		/*
770 		 * The disk must be active because we're syncing.
771 		 * We schedule log work now (now that the disk is
772 		 * active) instead of later (when it might not be).
773 		 */
774 		flush_delayed_work(&mp->m_log->l_work);
775 	}
776 
777 	return 0;
778 }
779 
780 STATIC int
781 xfs_fs_statfs(
782 	struct dentry		*dentry,
783 	struct kstatfs		*statp)
784 {
785 	struct xfs_mount	*mp = XFS_M(dentry->d_sb);
786 	xfs_sb_t		*sbp = &mp->m_sb;
787 	struct xfs_inode	*ip = XFS_I(d_inode(dentry));
788 	uint64_t		fakeinos, id;
789 	uint64_t		icount;
790 	uint64_t		ifree;
791 	uint64_t		fdblocks;
792 	xfs_extlen_t		lsize;
793 	int64_t			ffree;
794 
795 	statp->f_type = XFS_SUPER_MAGIC;
796 	statp->f_namelen = MAXNAMELEN - 1;
797 
798 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
799 	statp->f_fsid = u64_to_fsid(id);
800 
801 	icount = percpu_counter_sum(&mp->m_icount);
802 	ifree = percpu_counter_sum(&mp->m_ifree);
803 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
804 
805 	spin_lock(&mp->m_sb_lock);
806 	statp->f_bsize = sbp->sb_blocksize;
807 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
808 	statp->f_blocks = sbp->sb_dblocks - lsize;
809 	spin_unlock(&mp->m_sb_lock);
810 
811 	/* make sure statp->f_bfree does not underflow */
812 	statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0);
813 	statp->f_bavail = statp->f_bfree;
814 
815 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
816 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
817 	if (M_IGEO(mp)->maxicount)
818 		statp->f_files = min_t(typeof(statp->f_files),
819 					statp->f_files,
820 					M_IGEO(mp)->maxicount);
821 
822 	/* If sb_icount overshot maxicount, report actual allocation */
823 	statp->f_files = max_t(typeof(statp->f_files),
824 					statp->f_files,
825 					sbp->sb_icount);
826 
827 	/* make sure statp->f_ffree does not underflow */
828 	ffree = statp->f_files - (icount - ifree);
829 	statp->f_ffree = max_t(int64_t, ffree, 0);
830 
831 
832 	if ((ip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
833 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
834 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
835 		xfs_qm_statvfs(ip, statp);
836 
837 	if (XFS_IS_REALTIME_MOUNT(mp) &&
838 	    (ip->i_d.di_flags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
839 		statp->f_blocks = sbp->sb_rblocks;
840 		statp->f_bavail = statp->f_bfree =
841 			sbp->sb_frextents * sbp->sb_rextsize;
842 	}
843 
844 	return 0;
845 }
846 
847 STATIC void
848 xfs_save_resvblks(struct xfs_mount *mp)
849 {
850 	uint64_t resblks = 0;
851 
852 	mp->m_resblks_save = mp->m_resblks;
853 	xfs_reserve_blocks(mp, &resblks, NULL);
854 }
855 
856 STATIC void
857 xfs_restore_resvblks(struct xfs_mount *mp)
858 {
859 	uint64_t resblks;
860 
861 	if (mp->m_resblks_save) {
862 		resblks = mp->m_resblks_save;
863 		mp->m_resblks_save = 0;
864 	} else
865 		resblks = xfs_default_resblks(mp);
866 
867 	xfs_reserve_blocks(mp, &resblks, NULL);
868 }
869 
870 /*
871  * Trigger writeback of all the dirty metadata in the file system.
872  *
873  * This ensures that the metadata is written to their location on disk rather
874  * than just existing in transactions in the log. This means after a quiesce
875  * there is no log replay required to write the inodes to disk - this is the
876  * primary difference between a sync and a quiesce.
877  *
878  * We cancel log work early here to ensure all transactions the log worker may
879  * run have finished before we clean up and log the superblock and write an
880  * unmount record. The unfreeze process is responsible for restarting the log
881  * worker correctly.
882  */
883 void
884 xfs_quiesce_attr(
885 	struct xfs_mount	*mp)
886 {
887 	int	error = 0;
888 
889 	cancel_delayed_work_sync(&mp->m_log->l_work);
890 
891 	/* force the log to unpin objects from the now complete transactions */
892 	xfs_log_force(mp, XFS_LOG_SYNC);
893 
894 
895 	/* Push the superblock and write an unmount record */
896 	error = xfs_log_sbcount(mp);
897 	if (error)
898 		xfs_warn(mp, "xfs_attr_quiesce: failed to log sb changes. "
899 				"Frozen image may not be consistent.");
900 	xfs_log_quiesce(mp);
901 }
902 
903 /*
904  * Second stage of a freeze. The data is already frozen so we only
905  * need to take care of the metadata. Once that's done sync the superblock
906  * to the log to dirty it in case of a crash while frozen. This ensures that we
907  * will recover the unlinked inode lists on the next mount.
908  */
909 STATIC int
910 xfs_fs_freeze(
911 	struct super_block	*sb)
912 {
913 	struct xfs_mount	*mp = XFS_M(sb);
914 	unsigned int		flags;
915 	int			ret;
916 
917 	/*
918 	 * The filesystem is now frozen far enough that memory reclaim
919 	 * cannot safely operate on the filesystem. Hence we need to
920 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
921 	 */
922 	flags = memalloc_nofs_save();
923 	xfs_stop_block_reaping(mp);
924 	xfs_save_resvblks(mp);
925 	xfs_quiesce_attr(mp);
926 	ret = xfs_sync_sb(mp, true);
927 	memalloc_nofs_restore(flags);
928 	return ret;
929 }
930 
931 STATIC int
932 xfs_fs_unfreeze(
933 	struct super_block	*sb)
934 {
935 	struct xfs_mount	*mp = XFS_M(sb);
936 
937 	xfs_restore_resvblks(mp);
938 	xfs_log_work_queue(mp);
939 	xfs_start_block_reaping(mp);
940 	return 0;
941 }
942 
943 /*
944  * This function fills in xfs_mount_t fields based on mount args.
945  * Note: the superblock _has_ now been read in.
946  */
947 STATIC int
948 xfs_finish_flags(
949 	struct xfs_mount	*mp)
950 {
951 	int			ronly = (mp->m_flags & XFS_MOUNT_RDONLY);
952 
953 	/* Fail a mount where the logbuf is smaller than the log stripe */
954 	if (xfs_sb_version_haslogv2(&mp->m_sb)) {
955 		if (mp->m_logbsize <= 0 &&
956 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
957 			mp->m_logbsize = mp->m_sb.sb_logsunit;
958 		} else if (mp->m_logbsize > 0 &&
959 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
960 			xfs_warn(mp,
961 		"logbuf size must be greater than or equal to log stripe size");
962 			return -EINVAL;
963 		}
964 	} else {
965 		/* Fail a mount if the logbuf is larger than 32K */
966 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
967 			xfs_warn(mp,
968 		"logbuf size for version 1 logs must be 16K or 32K");
969 			return -EINVAL;
970 		}
971 	}
972 
973 	/*
974 	 * V5 filesystems always use attr2 format for attributes.
975 	 */
976 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
977 	    (mp->m_flags & XFS_MOUNT_NOATTR2)) {
978 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
979 			     "attr2 is always enabled for V5 filesystems.");
980 		return -EINVAL;
981 	}
982 
983 	/*
984 	 * mkfs'ed attr2 will turn on attr2 mount unless explicitly
985 	 * told by noattr2 to turn it off
986 	 */
987 	if (xfs_sb_version_hasattr2(&mp->m_sb) &&
988 	    !(mp->m_flags & XFS_MOUNT_NOATTR2))
989 		mp->m_flags |= XFS_MOUNT_ATTR2;
990 
991 	/*
992 	 * prohibit r/w mounts of read-only filesystems
993 	 */
994 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !ronly) {
995 		xfs_warn(mp,
996 			"cannot mount a read-only filesystem as read-write");
997 		return -EROFS;
998 	}
999 
1000 	if ((mp->m_qflags & (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE)) &&
1001 	    (mp->m_qflags & (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE)) &&
1002 	    !xfs_sb_version_has_pquotino(&mp->m_sb)) {
1003 		xfs_warn(mp,
1004 		  "Super block does not support project and group quota together");
1005 		return -EINVAL;
1006 	}
1007 
1008 	return 0;
1009 }
1010 
1011 static int
1012 xfs_init_percpu_counters(
1013 	struct xfs_mount	*mp)
1014 {
1015 	int		error;
1016 
1017 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
1018 	if (error)
1019 		return -ENOMEM;
1020 
1021 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
1022 	if (error)
1023 		goto free_icount;
1024 
1025 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
1026 	if (error)
1027 		goto free_ifree;
1028 
1029 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
1030 	if (error)
1031 		goto free_fdblocks;
1032 
1033 	return 0;
1034 
1035 free_fdblocks:
1036 	percpu_counter_destroy(&mp->m_fdblocks);
1037 free_ifree:
1038 	percpu_counter_destroy(&mp->m_ifree);
1039 free_icount:
1040 	percpu_counter_destroy(&mp->m_icount);
1041 	return -ENOMEM;
1042 }
1043 
1044 void
1045 xfs_reinit_percpu_counters(
1046 	struct xfs_mount	*mp)
1047 {
1048 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1049 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1050 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1051 }
1052 
1053 static void
1054 xfs_destroy_percpu_counters(
1055 	struct xfs_mount	*mp)
1056 {
1057 	percpu_counter_destroy(&mp->m_icount);
1058 	percpu_counter_destroy(&mp->m_ifree);
1059 	percpu_counter_destroy(&mp->m_fdblocks);
1060 	ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
1061 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1062 	percpu_counter_destroy(&mp->m_delalloc_blks);
1063 }
1064 
1065 static void
1066 xfs_fs_put_super(
1067 	struct super_block	*sb)
1068 {
1069 	struct xfs_mount	*mp = XFS_M(sb);
1070 
1071 	/* if ->fill_super failed, we have no mount to tear down */
1072 	if (!sb->s_fs_info)
1073 		return;
1074 
1075 	xfs_notice(mp, "Unmounting Filesystem");
1076 	xfs_filestream_unmount(mp);
1077 	xfs_unmountfs(mp);
1078 
1079 	xfs_freesb(mp);
1080 	free_percpu(mp->m_stats.xs_stats);
1081 	xfs_destroy_percpu_counters(mp);
1082 	xfs_destroy_mount_workqueues(mp);
1083 	xfs_close_devices(mp);
1084 
1085 	sb->s_fs_info = NULL;
1086 	xfs_mount_free(mp);
1087 }
1088 
1089 static long
1090 xfs_fs_nr_cached_objects(
1091 	struct super_block	*sb,
1092 	struct shrink_control	*sc)
1093 {
1094 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1095 	if (WARN_ON_ONCE(!sb->s_fs_info))
1096 		return 0;
1097 	return xfs_reclaim_inodes_count(XFS_M(sb));
1098 }
1099 
1100 static long
1101 xfs_fs_free_cached_objects(
1102 	struct super_block	*sb,
1103 	struct shrink_control	*sc)
1104 {
1105 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1106 }
1107 
1108 static const struct super_operations xfs_super_operations = {
1109 	.alloc_inode		= xfs_fs_alloc_inode,
1110 	.destroy_inode		= xfs_fs_destroy_inode,
1111 	.dirty_inode		= xfs_fs_dirty_inode,
1112 	.drop_inode		= xfs_fs_drop_inode,
1113 	.put_super		= xfs_fs_put_super,
1114 	.sync_fs		= xfs_fs_sync_fs,
1115 	.freeze_fs		= xfs_fs_freeze,
1116 	.unfreeze_fs		= xfs_fs_unfreeze,
1117 	.statfs			= xfs_fs_statfs,
1118 	.show_options		= xfs_fs_show_options,
1119 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1120 	.free_cached_objects	= xfs_fs_free_cached_objects,
1121 };
1122 
1123 static int
1124 suffix_kstrtoint(
1125 	const char	*s,
1126 	unsigned int	base,
1127 	int		*res)
1128 {
1129 	int		last, shift_left_factor = 0, _res;
1130 	char		*value;
1131 	int		ret = 0;
1132 
1133 	value = kstrdup(s, GFP_KERNEL);
1134 	if (!value)
1135 		return -ENOMEM;
1136 
1137 	last = strlen(value) - 1;
1138 	if (value[last] == 'K' || value[last] == 'k') {
1139 		shift_left_factor = 10;
1140 		value[last] = '\0';
1141 	}
1142 	if (value[last] == 'M' || value[last] == 'm') {
1143 		shift_left_factor = 20;
1144 		value[last] = '\0';
1145 	}
1146 	if (value[last] == 'G' || value[last] == 'g') {
1147 		shift_left_factor = 30;
1148 		value[last] = '\0';
1149 	}
1150 
1151 	if (kstrtoint(value, base, &_res))
1152 		ret = -EINVAL;
1153 	kfree(value);
1154 	*res = _res << shift_left_factor;
1155 	return ret;
1156 }
1157 
1158 /*
1159  * Set mount state from a mount option.
1160  *
1161  * NOTE: mp->m_super is NULL here!
1162  */
1163 static int
1164 xfs_fs_parse_param(
1165 	struct fs_context	*fc,
1166 	struct fs_parameter	*param)
1167 {
1168 	struct xfs_mount	*mp = fc->s_fs_info;
1169 	struct fs_parse_result	result;
1170 	int			size = 0;
1171 	int			opt;
1172 
1173 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1174 	if (opt < 0)
1175 		return opt;
1176 
1177 	switch (opt) {
1178 	case Opt_logbufs:
1179 		mp->m_logbufs = result.uint_32;
1180 		return 0;
1181 	case Opt_logbsize:
1182 		if (suffix_kstrtoint(param->string, 10, &mp->m_logbsize))
1183 			return -EINVAL;
1184 		return 0;
1185 	case Opt_logdev:
1186 		kfree(mp->m_logname);
1187 		mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1188 		if (!mp->m_logname)
1189 			return -ENOMEM;
1190 		return 0;
1191 	case Opt_rtdev:
1192 		kfree(mp->m_rtname);
1193 		mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1194 		if (!mp->m_rtname)
1195 			return -ENOMEM;
1196 		return 0;
1197 	case Opt_allocsize:
1198 		if (suffix_kstrtoint(param->string, 10, &size))
1199 			return -EINVAL;
1200 		mp->m_allocsize_log = ffs(size) - 1;
1201 		mp->m_flags |= XFS_MOUNT_ALLOCSIZE;
1202 		return 0;
1203 	case Opt_grpid:
1204 	case Opt_bsdgroups:
1205 		mp->m_flags |= XFS_MOUNT_GRPID;
1206 		return 0;
1207 	case Opt_nogrpid:
1208 	case Opt_sysvgroups:
1209 		mp->m_flags &= ~XFS_MOUNT_GRPID;
1210 		return 0;
1211 	case Opt_wsync:
1212 		mp->m_flags |= XFS_MOUNT_WSYNC;
1213 		return 0;
1214 	case Opt_norecovery:
1215 		mp->m_flags |= XFS_MOUNT_NORECOVERY;
1216 		return 0;
1217 	case Opt_noalign:
1218 		mp->m_flags |= XFS_MOUNT_NOALIGN;
1219 		return 0;
1220 	case Opt_swalloc:
1221 		mp->m_flags |= XFS_MOUNT_SWALLOC;
1222 		return 0;
1223 	case Opt_sunit:
1224 		mp->m_dalign = result.uint_32;
1225 		return 0;
1226 	case Opt_swidth:
1227 		mp->m_swidth = result.uint_32;
1228 		return 0;
1229 	case Opt_inode32:
1230 		mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1231 		return 0;
1232 	case Opt_inode64:
1233 		mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1234 		return 0;
1235 	case Opt_nouuid:
1236 		mp->m_flags |= XFS_MOUNT_NOUUID;
1237 		return 0;
1238 	case Opt_largeio:
1239 		mp->m_flags |= XFS_MOUNT_LARGEIO;
1240 		return 0;
1241 	case Opt_nolargeio:
1242 		mp->m_flags &= ~XFS_MOUNT_LARGEIO;
1243 		return 0;
1244 	case Opt_filestreams:
1245 		mp->m_flags |= XFS_MOUNT_FILESTREAMS;
1246 		return 0;
1247 	case Opt_noquota:
1248 		mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1249 		mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1250 		mp->m_qflags &= ~XFS_ALL_QUOTA_ACTIVE;
1251 		return 0;
1252 	case Opt_quota:
1253 	case Opt_uquota:
1254 	case Opt_usrquota:
1255 		mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE |
1256 				 XFS_UQUOTA_ENFD);
1257 		return 0;
1258 	case Opt_qnoenforce:
1259 	case Opt_uqnoenforce:
1260 		mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE);
1261 		mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1262 		return 0;
1263 	case Opt_pquota:
1264 	case Opt_prjquota:
1265 		mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE |
1266 				 XFS_PQUOTA_ENFD);
1267 		return 0;
1268 	case Opt_pqnoenforce:
1269 		mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE);
1270 		mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1271 		return 0;
1272 	case Opt_gquota:
1273 	case Opt_grpquota:
1274 		mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE |
1275 				 XFS_GQUOTA_ENFD);
1276 		return 0;
1277 	case Opt_gqnoenforce:
1278 		mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE);
1279 		mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1280 		return 0;
1281 	case Opt_discard:
1282 		mp->m_flags |= XFS_MOUNT_DISCARD;
1283 		return 0;
1284 	case Opt_nodiscard:
1285 		mp->m_flags &= ~XFS_MOUNT_DISCARD;
1286 		return 0;
1287 #ifdef CONFIG_FS_DAX
1288 	case Opt_dax:
1289 		xfs_mount_set_dax_mode(mp, XFS_DAX_ALWAYS);
1290 		return 0;
1291 	case Opt_dax_enum:
1292 		xfs_mount_set_dax_mode(mp, result.uint_32);
1293 		return 0;
1294 #endif
1295 	/* Following mount options will be removed in September 2025 */
1296 	case Opt_ikeep:
1297 		xfs_warn(mp, "%s mount option is deprecated.", param->key);
1298 		mp->m_flags |= XFS_MOUNT_IKEEP;
1299 		return 0;
1300 	case Opt_noikeep:
1301 		xfs_warn(mp, "%s mount option is deprecated.", param->key);
1302 		mp->m_flags &= ~XFS_MOUNT_IKEEP;
1303 		return 0;
1304 	case Opt_attr2:
1305 		xfs_warn(mp, "%s mount option is deprecated.", param->key);
1306 		mp->m_flags |= XFS_MOUNT_ATTR2;
1307 		return 0;
1308 	case Opt_noattr2:
1309 		xfs_warn(mp, "%s mount option is deprecated.", param->key);
1310 		mp->m_flags &= ~XFS_MOUNT_ATTR2;
1311 		mp->m_flags |= XFS_MOUNT_NOATTR2;
1312 		return 0;
1313 	default:
1314 		xfs_warn(mp, "unknown mount option [%s].", param->key);
1315 		return -EINVAL;
1316 	}
1317 
1318 	return 0;
1319 }
1320 
1321 static int
1322 xfs_fs_validate_params(
1323 	struct xfs_mount	*mp)
1324 {
1325 	/*
1326 	 * no recovery flag requires a read-only mount
1327 	 */
1328 	if ((mp->m_flags & XFS_MOUNT_NORECOVERY) &&
1329 	    !(mp->m_flags & XFS_MOUNT_RDONLY)) {
1330 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1331 		return -EINVAL;
1332 	}
1333 
1334 	if ((mp->m_flags & XFS_MOUNT_NOALIGN) &&
1335 	    (mp->m_dalign || mp->m_swidth)) {
1336 		xfs_warn(mp,
1337 	"sunit and swidth options incompatible with the noalign option");
1338 		return -EINVAL;
1339 	}
1340 
1341 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1342 		xfs_warn(mp, "quota support not available in this kernel.");
1343 		return -EINVAL;
1344 	}
1345 
1346 	if ((mp->m_dalign && !mp->m_swidth) ||
1347 	    (!mp->m_dalign && mp->m_swidth)) {
1348 		xfs_warn(mp, "sunit and swidth must be specified together");
1349 		return -EINVAL;
1350 	}
1351 
1352 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1353 		xfs_warn(mp,
1354 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1355 			mp->m_swidth, mp->m_dalign);
1356 		return -EINVAL;
1357 	}
1358 
1359 	if (mp->m_logbufs != -1 &&
1360 	    mp->m_logbufs != 0 &&
1361 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1362 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1363 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1364 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1365 		return -EINVAL;
1366 	}
1367 
1368 	if (mp->m_logbsize != -1 &&
1369 	    mp->m_logbsize !=  0 &&
1370 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1371 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1372 	     !is_power_of_2(mp->m_logbsize))) {
1373 		xfs_warn(mp,
1374 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1375 			mp->m_logbsize);
1376 		return -EINVAL;
1377 	}
1378 
1379 	if ((mp->m_flags & XFS_MOUNT_ALLOCSIZE) &&
1380 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1381 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1382 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1383 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1384 		return -EINVAL;
1385 	}
1386 
1387 	return 0;
1388 }
1389 
1390 static int
1391 xfs_fs_fill_super(
1392 	struct super_block	*sb,
1393 	struct fs_context	*fc)
1394 {
1395 	struct xfs_mount	*mp = sb->s_fs_info;
1396 	struct inode		*root;
1397 	int			flags = 0, error;
1398 
1399 	mp->m_super = sb;
1400 
1401 	error = xfs_fs_validate_params(mp);
1402 	if (error)
1403 		goto out_free_names;
1404 
1405 	sb_min_blocksize(sb, BBSIZE);
1406 	sb->s_xattr = xfs_xattr_handlers;
1407 	sb->s_export_op = &xfs_export_operations;
1408 #ifdef CONFIG_XFS_QUOTA
1409 	sb->s_qcop = &xfs_quotactl_operations;
1410 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1411 #endif
1412 	sb->s_op = &xfs_super_operations;
1413 
1414 	/*
1415 	 * Delay mount work if the debug hook is set. This is debug
1416 	 * instrumention to coordinate simulation of xfs mount failures with
1417 	 * VFS superblock operations
1418 	 */
1419 	if (xfs_globals.mount_delay) {
1420 		xfs_notice(mp, "Delaying mount for %d seconds.",
1421 			xfs_globals.mount_delay);
1422 		msleep(xfs_globals.mount_delay * 1000);
1423 	}
1424 
1425 	if (fc->sb_flags & SB_SILENT)
1426 		flags |= XFS_MFSI_QUIET;
1427 
1428 	error = xfs_open_devices(mp);
1429 	if (error)
1430 		goto out_free_names;
1431 
1432 	error = xfs_init_mount_workqueues(mp);
1433 	if (error)
1434 		goto out_close_devices;
1435 
1436 	error = xfs_init_percpu_counters(mp);
1437 	if (error)
1438 		goto out_destroy_workqueues;
1439 
1440 	/* Allocate stats memory before we do operations that might use it */
1441 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1442 	if (!mp->m_stats.xs_stats) {
1443 		error = -ENOMEM;
1444 		goto out_destroy_counters;
1445 	}
1446 
1447 	error = xfs_readsb(mp, flags);
1448 	if (error)
1449 		goto out_free_stats;
1450 
1451 	error = xfs_finish_flags(mp);
1452 	if (error)
1453 		goto out_free_sb;
1454 
1455 	error = xfs_setup_devices(mp);
1456 	if (error)
1457 		goto out_free_sb;
1458 
1459 	/* V4 support is undergoing deprecation. */
1460 	if (!xfs_sb_version_hascrc(&mp->m_sb)) {
1461 #ifdef CONFIG_XFS_SUPPORT_V4
1462 		xfs_warn_once(mp,
1463 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1464 #else
1465 		xfs_warn(mp,
1466 	"Deprecated V4 format (crc=0) not supported by kernel.");
1467 		error = -EINVAL;
1468 		goto out_free_sb;
1469 #endif
1470 	}
1471 
1472 	/* Filesystem claims it needs repair, so refuse the mount. */
1473 	if (xfs_sb_version_needsrepair(&mp->m_sb)) {
1474 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1475 		error = -EFSCORRUPTED;
1476 		goto out_free_sb;
1477 	}
1478 
1479 	/*
1480 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1481 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1482 	 * we don't check them at all.
1483 	 */
1484 	if (mp->m_sb.sb_inprogress) {
1485 		xfs_warn(mp, "Offline file system operation in progress!");
1486 		error = -EFSCORRUPTED;
1487 		goto out_free_sb;
1488 	}
1489 
1490 	/*
1491 	 * Until this is fixed only page-sized or smaller data blocks work.
1492 	 */
1493 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1494 		xfs_warn(mp,
1495 		"File system with blocksize %d bytes. "
1496 		"Only pagesize (%ld) or less will currently work.",
1497 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1498 		error = -ENOSYS;
1499 		goto out_free_sb;
1500 	}
1501 
1502 	/* Ensure this filesystem fits in the page cache limits */
1503 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1504 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1505 		xfs_warn(mp,
1506 		"file system too large to be mounted on this system.");
1507 		error = -EFBIG;
1508 		goto out_free_sb;
1509 	}
1510 
1511 	/*
1512 	 * XFS block mappings use 54 bits to store the logical block offset.
1513 	 * This should suffice to handle the maximum file size that the VFS
1514 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1515 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1516 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1517 	 * to check this assertion.
1518 	 *
1519 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1520 	 * maximum pagecache offset in units of fs blocks.
1521 	 */
1522 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1523 		xfs_warn(mp,
1524 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1525 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1526 			 XFS_MAX_FILEOFF);
1527 		error = -EINVAL;
1528 		goto out_free_sb;
1529 	}
1530 
1531 	error = xfs_filestream_mount(mp);
1532 	if (error)
1533 		goto out_free_sb;
1534 
1535 	/*
1536 	 * we must configure the block size in the superblock before we run the
1537 	 * full mount process as the mount process can lookup and cache inodes.
1538 	 */
1539 	sb->s_magic = XFS_SUPER_MAGIC;
1540 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1541 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1542 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1543 	sb->s_max_links = XFS_MAXLINK;
1544 	sb->s_time_gran = 1;
1545 	if (xfs_sb_version_hasbigtime(&mp->m_sb)) {
1546 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1547 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1548 	} else {
1549 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1550 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1551 	}
1552 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1553 	sb->s_iflags |= SB_I_CGROUPWB;
1554 
1555 	set_posix_acl_flag(sb);
1556 
1557 	/* version 5 superblocks support inode version counters. */
1558 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1559 		sb->s_flags |= SB_I_VERSION;
1560 
1561 	if (xfs_sb_version_hasbigtime(&mp->m_sb))
1562 		xfs_warn(mp,
1563  "EXPERIMENTAL big timestamp feature in use. Use at your own risk!");
1564 
1565 	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS) {
1566 		bool rtdev_is_dax = false, datadev_is_dax;
1567 
1568 		xfs_warn(mp,
1569 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1570 
1571 		datadev_is_dax = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
1572 			sb->s_blocksize);
1573 		if (mp->m_rtdev_targp)
1574 			rtdev_is_dax = bdev_dax_supported(
1575 				mp->m_rtdev_targp->bt_bdev, sb->s_blocksize);
1576 		if (!rtdev_is_dax && !datadev_is_dax) {
1577 			xfs_alert(mp,
1578 			"DAX unsupported by block device. Turning off DAX.");
1579 			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
1580 		}
1581 		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1582 			xfs_alert(mp,
1583 		"DAX and reflink cannot be used together!");
1584 			error = -EINVAL;
1585 			goto out_filestream_unmount;
1586 		}
1587 	}
1588 
1589 	if (mp->m_flags & XFS_MOUNT_DISCARD) {
1590 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1591 
1592 		if (!blk_queue_discard(q)) {
1593 			xfs_warn(mp, "mounting with \"discard\" option, but "
1594 					"the device does not support discard");
1595 			mp->m_flags &= ~XFS_MOUNT_DISCARD;
1596 		}
1597 	}
1598 
1599 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1600 		if (mp->m_sb.sb_rblocks) {
1601 			xfs_alert(mp,
1602 	"reflink not compatible with realtime device!");
1603 			error = -EINVAL;
1604 			goto out_filestream_unmount;
1605 		}
1606 
1607 		if (xfs_globals.always_cow) {
1608 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1609 			mp->m_always_cow = true;
1610 		}
1611 	}
1612 
1613 	if (xfs_sb_version_hasrmapbt(&mp->m_sb) && mp->m_sb.sb_rblocks) {
1614 		xfs_alert(mp,
1615 	"reverse mapping btree not compatible with realtime device!");
1616 		error = -EINVAL;
1617 		goto out_filestream_unmount;
1618 	}
1619 
1620 	if (xfs_sb_version_hasinobtcounts(&mp->m_sb))
1621 		xfs_warn(mp,
1622  "EXPERIMENTAL inode btree counters feature in use. Use at your own risk!");
1623 
1624 	error = xfs_mountfs(mp);
1625 	if (error)
1626 		goto out_filestream_unmount;
1627 
1628 	root = igrab(VFS_I(mp->m_rootip));
1629 	if (!root) {
1630 		error = -ENOENT;
1631 		goto out_unmount;
1632 	}
1633 	sb->s_root = d_make_root(root);
1634 	if (!sb->s_root) {
1635 		error = -ENOMEM;
1636 		goto out_unmount;
1637 	}
1638 
1639 	return 0;
1640 
1641  out_filestream_unmount:
1642 	xfs_filestream_unmount(mp);
1643  out_free_sb:
1644 	xfs_freesb(mp);
1645  out_free_stats:
1646 	free_percpu(mp->m_stats.xs_stats);
1647  out_destroy_counters:
1648 	xfs_destroy_percpu_counters(mp);
1649  out_destroy_workqueues:
1650 	xfs_destroy_mount_workqueues(mp);
1651  out_close_devices:
1652 	xfs_close_devices(mp);
1653  out_free_names:
1654 	sb->s_fs_info = NULL;
1655 	xfs_mount_free(mp);
1656 	return error;
1657 
1658  out_unmount:
1659 	xfs_filestream_unmount(mp);
1660 	xfs_unmountfs(mp);
1661 	goto out_free_sb;
1662 }
1663 
1664 static int
1665 xfs_fs_get_tree(
1666 	struct fs_context	*fc)
1667 {
1668 	return get_tree_bdev(fc, xfs_fs_fill_super);
1669 }
1670 
1671 static int
1672 xfs_remount_rw(
1673 	struct xfs_mount	*mp)
1674 {
1675 	struct xfs_sb		*sbp = &mp->m_sb;
1676 	int error;
1677 
1678 	if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
1679 		xfs_warn(mp,
1680 			"ro->rw transition prohibited on norecovery mount");
1681 		return -EINVAL;
1682 	}
1683 
1684 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
1685 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1686 		xfs_warn(mp,
1687 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1688 			(sbp->sb_features_ro_compat &
1689 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1690 		return -EINVAL;
1691 	}
1692 
1693 	mp->m_flags &= ~XFS_MOUNT_RDONLY;
1694 
1695 	/*
1696 	 * If this is the first remount to writeable state we might have some
1697 	 * superblock changes to update.
1698 	 */
1699 	if (mp->m_update_sb) {
1700 		error = xfs_sync_sb(mp, false);
1701 		if (error) {
1702 			xfs_warn(mp, "failed to write sb changes");
1703 			return error;
1704 		}
1705 		mp->m_update_sb = false;
1706 	}
1707 
1708 	/*
1709 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1710 	 * it is non-zero, otherwise go with the default.
1711 	 */
1712 	xfs_restore_resvblks(mp);
1713 	xfs_log_work_queue(mp);
1714 
1715 	/* Recover any CoW blocks that never got remapped. */
1716 	error = xfs_reflink_recover_cow(mp);
1717 	if (error) {
1718 		xfs_err(mp,
1719 			"Error %d recovering leftover CoW allocations.", error);
1720 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1721 		return error;
1722 	}
1723 	xfs_start_block_reaping(mp);
1724 
1725 	/* Create the per-AG metadata reservation pool .*/
1726 	error = xfs_fs_reserve_ag_blocks(mp);
1727 	if (error && error != -ENOSPC)
1728 		return error;
1729 
1730 	return 0;
1731 }
1732 
1733 static int
1734 xfs_remount_ro(
1735 	struct xfs_mount	*mp)
1736 {
1737 	int error;
1738 
1739 	/*
1740 	 * Cancel background eofb scanning so it cannot race with the final
1741 	 * log force+buftarg wait and deadlock the remount.
1742 	 */
1743 	xfs_stop_block_reaping(mp);
1744 
1745 	/* Get rid of any leftover CoW reservations... */
1746 	error = xfs_icache_free_cowblocks(mp, NULL);
1747 	if (error) {
1748 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1749 		return error;
1750 	}
1751 
1752 	/* Free the per-AG metadata reservation pool. */
1753 	error = xfs_fs_unreserve_ag_blocks(mp);
1754 	if (error) {
1755 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1756 		return error;
1757 	}
1758 
1759 	/*
1760 	 * Before we sync the metadata, we need to free up the reserve block
1761 	 * pool so that the used block count in the superblock on disk is
1762 	 * correct at the end of the remount. Stash the current* reserve pool
1763 	 * size so that if we get remounted rw, we can return it to the same
1764 	 * size.
1765 	 */
1766 	xfs_save_resvblks(mp);
1767 
1768 	xfs_quiesce_attr(mp);
1769 	mp->m_flags |= XFS_MOUNT_RDONLY;
1770 
1771 	return 0;
1772 }
1773 
1774 /*
1775  * Logically we would return an error here to prevent users from believing
1776  * they might have changed mount options using remount which can't be changed.
1777  *
1778  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1779  * arguments in some cases so we can't blindly reject options, but have to
1780  * check for each specified option if it actually differs from the currently
1781  * set option and only reject it if that's the case.
1782  *
1783  * Until that is implemented we return success for every remount request, and
1784  * silently ignore all options that we can't actually change.
1785  */
1786 static int
1787 xfs_fs_reconfigure(
1788 	struct fs_context *fc)
1789 {
1790 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1791 	struct xfs_mount        *new_mp = fc->s_fs_info;
1792 	xfs_sb_t		*sbp = &mp->m_sb;
1793 	int			flags = fc->sb_flags;
1794 	int			error;
1795 
1796 	/* version 5 superblocks always support version counters. */
1797 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1798 		fc->sb_flags |= SB_I_VERSION;
1799 
1800 	error = xfs_fs_validate_params(new_mp);
1801 	if (error)
1802 		return error;
1803 
1804 	sync_filesystem(mp->m_super);
1805 
1806 	/* inode32 -> inode64 */
1807 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1808 	    !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1809 		mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1810 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1811 	}
1812 
1813 	/* inode64 -> inode32 */
1814 	if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1815 	    (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1816 		mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1817 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1818 	}
1819 
1820 	/* ro -> rw */
1821 	if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) {
1822 		error = xfs_remount_rw(mp);
1823 		if (error)
1824 			return error;
1825 	}
1826 
1827 	/* rw -> ro */
1828 	if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) {
1829 		error = xfs_remount_ro(mp);
1830 		if (error)
1831 			return error;
1832 	}
1833 
1834 	return 0;
1835 }
1836 
1837 static void xfs_fs_free(
1838 	struct fs_context	*fc)
1839 {
1840 	struct xfs_mount	*mp = fc->s_fs_info;
1841 
1842 	/*
1843 	 * mp is stored in the fs_context when it is initialized.
1844 	 * mp is transferred to the superblock on a successful mount,
1845 	 * but if an error occurs before the transfer we have to free
1846 	 * it here.
1847 	 */
1848 	if (mp)
1849 		xfs_mount_free(mp);
1850 }
1851 
1852 static const struct fs_context_operations xfs_context_ops = {
1853 	.parse_param = xfs_fs_parse_param,
1854 	.get_tree    = xfs_fs_get_tree,
1855 	.reconfigure = xfs_fs_reconfigure,
1856 	.free        = xfs_fs_free,
1857 };
1858 
1859 static int xfs_init_fs_context(
1860 	struct fs_context	*fc)
1861 {
1862 	struct xfs_mount	*mp;
1863 
1864 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1865 	if (!mp)
1866 		return -ENOMEM;
1867 
1868 	spin_lock_init(&mp->m_sb_lock);
1869 	spin_lock_init(&mp->m_agirotor_lock);
1870 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1871 	spin_lock_init(&mp->m_perag_lock);
1872 	mutex_init(&mp->m_growlock);
1873 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1874 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1875 	INIT_DELAYED_WORK(&mp->m_eofblocks_work, xfs_eofblocks_worker);
1876 	INIT_DELAYED_WORK(&mp->m_cowblocks_work, xfs_cowblocks_worker);
1877 	mp->m_kobj.kobject.kset = xfs_kset;
1878 	/*
1879 	 * We don't create the finobt per-ag space reservation until after log
1880 	 * recovery, so we must set this to true so that an ifree transaction
1881 	 * started during log recovery will not depend on space reservations
1882 	 * for finobt expansion.
1883 	 */
1884 	mp->m_finobt_nores = true;
1885 
1886 	/*
1887 	 * These can be overridden by the mount option parsing.
1888 	 */
1889 	mp->m_logbufs = -1;
1890 	mp->m_logbsize = -1;
1891 	mp->m_allocsize_log = 16; /* 64k */
1892 
1893 	/*
1894 	 * Copy binary VFS mount flags we are interested in.
1895 	 */
1896 	if (fc->sb_flags & SB_RDONLY)
1897 		mp->m_flags |= XFS_MOUNT_RDONLY;
1898 	if (fc->sb_flags & SB_DIRSYNC)
1899 		mp->m_flags |= XFS_MOUNT_DIRSYNC;
1900 	if (fc->sb_flags & SB_SYNCHRONOUS)
1901 		mp->m_flags |= XFS_MOUNT_WSYNC;
1902 
1903 	fc->s_fs_info = mp;
1904 	fc->ops = &xfs_context_ops;
1905 
1906 	return 0;
1907 }
1908 
1909 static struct file_system_type xfs_fs_type = {
1910 	.owner			= THIS_MODULE,
1911 	.name			= "xfs",
1912 	.init_fs_context	= xfs_init_fs_context,
1913 	.parameters		= xfs_fs_parameters,
1914 	.kill_sb		= kill_block_super,
1915 	.fs_flags		= FS_REQUIRES_DEV,
1916 };
1917 MODULE_ALIAS_FS("xfs");
1918 
1919 STATIC int __init
1920 xfs_init_zones(void)
1921 {
1922 	xfs_log_ticket_zone = kmem_cache_create("xfs_log_ticket",
1923 						sizeof(struct xlog_ticket),
1924 						0, 0, NULL);
1925 	if (!xfs_log_ticket_zone)
1926 		goto out;
1927 
1928 	xfs_bmap_free_item_zone = kmem_cache_create("xfs_bmap_free_item",
1929 					sizeof(struct xfs_extent_free_item),
1930 					0, 0, NULL);
1931 	if (!xfs_bmap_free_item_zone)
1932 		goto out_destroy_log_ticket_zone;
1933 
1934 	xfs_btree_cur_zone = kmem_cache_create("xfs_btree_cur",
1935 					       sizeof(struct xfs_btree_cur),
1936 					       0, 0, NULL);
1937 	if (!xfs_btree_cur_zone)
1938 		goto out_destroy_bmap_free_item_zone;
1939 
1940 	xfs_da_state_zone = kmem_cache_create("xfs_da_state",
1941 					      sizeof(struct xfs_da_state),
1942 					      0, 0, NULL);
1943 	if (!xfs_da_state_zone)
1944 		goto out_destroy_btree_cur_zone;
1945 
1946 	xfs_ifork_zone = kmem_cache_create("xfs_ifork",
1947 					   sizeof(struct xfs_ifork),
1948 					   0, 0, NULL);
1949 	if (!xfs_ifork_zone)
1950 		goto out_destroy_da_state_zone;
1951 
1952 	xfs_trans_zone = kmem_cache_create("xf_trans",
1953 					   sizeof(struct xfs_trans),
1954 					   0, 0, NULL);
1955 	if (!xfs_trans_zone)
1956 		goto out_destroy_ifork_zone;
1957 
1958 
1959 	/*
1960 	 * The size of the zone allocated buf log item is the maximum
1961 	 * size possible under XFS.  This wastes a little bit of memory,
1962 	 * but it is much faster.
1963 	 */
1964 	xfs_buf_item_zone = kmem_cache_create("xfs_buf_item",
1965 					      sizeof(struct xfs_buf_log_item),
1966 					      0, 0, NULL);
1967 	if (!xfs_buf_item_zone)
1968 		goto out_destroy_trans_zone;
1969 
1970 	xfs_efd_zone = kmem_cache_create("xfs_efd_item",
1971 					(sizeof(struct xfs_efd_log_item) +
1972 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
1973 					sizeof(struct xfs_extent)),
1974 					0, 0, NULL);
1975 	if (!xfs_efd_zone)
1976 		goto out_destroy_buf_item_zone;
1977 
1978 	xfs_efi_zone = kmem_cache_create("xfs_efi_item",
1979 					 (sizeof(struct xfs_efi_log_item) +
1980 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
1981 					 sizeof(struct xfs_extent)),
1982 					 0, 0, NULL);
1983 	if (!xfs_efi_zone)
1984 		goto out_destroy_efd_zone;
1985 
1986 	xfs_inode_zone = kmem_cache_create("xfs_inode",
1987 					   sizeof(struct xfs_inode), 0,
1988 					   (SLAB_HWCACHE_ALIGN |
1989 					    SLAB_RECLAIM_ACCOUNT |
1990 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
1991 					   xfs_fs_inode_init_once);
1992 	if (!xfs_inode_zone)
1993 		goto out_destroy_efi_zone;
1994 
1995 	xfs_ili_zone = kmem_cache_create("xfs_ili",
1996 					 sizeof(struct xfs_inode_log_item), 0,
1997 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
1998 					 NULL);
1999 	if (!xfs_ili_zone)
2000 		goto out_destroy_inode_zone;
2001 
2002 	xfs_icreate_zone = kmem_cache_create("xfs_icr",
2003 					     sizeof(struct xfs_icreate_item),
2004 					     0, 0, NULL);
2005 	if (!xfs_icreate_zone)
2006 		goto out_destroy_ili_zone;
2007 
2008 	xfs_rud_zone = kmem_cache_create("xfs_rud_item",
2009 					 sizeof(struct xfs_rud_log_item),
2010 					 0, 0, NULL);
2011 	if (!xfs_rud_zone)
2012 		goto out_destroy_icreate_zone;
2013 
2014 	xfs_rui_zone = kmem_cache_create("xfs_rui_item",
2015 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
2016 			0, 0, NULL);
2017 	if (!xfs_rui_zone)
2018 		goto out_destroy_rud_zone;
2019 
2020 	xfs_cud_zone = kmem_cache_create("xfs_cud_item",
2021 					 sizeof(struct xfs_cud_log_item),
2022 					 0, 0, NULL);
2023 	if (!xfs_cud_zone)
2024 		goto out_destroy_rui_zone;
2025 
2026 	xfs_cui_zone = kmem_cache_create("xfs_cui_item",
2027 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2028 			0, 0, NULL);
2029 	if (!xfs_cui_zone)
2030 		goto out_destroy_cud_zone;
2031 
2032 	xfs_bud_zone = kmem_cache_create("xfs_bud_item",
2033 					 sizeof(struct xfs_bud_log_item),
2034 					 0, 0, NULL);
2035 	if (!xfs_bud_zone)
2036 		goto out_destroy_cui_zone;
2037 
2038 	xfs_bui_zone = kmem_cache_create("xfs_bui_item",
2039 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2040 			0, 0, NULL);
2041 	if (!xfs_bui_zone)
2042 		goto out_destroy_bud_zone;
2043 
2044 	return 0;
2045 
2046  out_destroy_bud_zone:
2047 	kmem_cache_destroy(xfs_bud_zone);
2048  out_destroy_cui_zone:
2049 	kmem_cache_destroy(xfs_cui_zone);
2050  out_destroy_cud_zone:
2051 	kmem_cache_destroy(xfs_cud_zone);
2052  out_destroy_rui_zone:
2053 	kmem_cache_destroy(xfs_rui_zone);
2054  out_destroy_rud_zone:
2055 	kmem_cache_destroy(xfs_rud_zone);
2056  out_destroy_icreate_zone:
2057 	kmem_cache_destroy(xfs_icreate_zone);
2058  out_destroy_ili_zone:
2059 	kmem_cache_destroy(xfs_ili_zone);
2060  out_destroy_inode_zone:
2061 	kmem_cache_destroy(xfs_inode_zone);
2062  out_destroy_efi_zone:
2063 	kmem_cache_destroy(xfs_efi_zone);
2064  out_destroy_efd_zone:
2065 	kmem_cache_destroy(xfs_efd_zone);
2066  out_destroy_buf_item_zone:
2067 	kmem_cache_destroy(xfs_buf_item_zone);
2068  out_destroy_trans_zone:
2069 	kmem_cache_destroy(xfs_trans_zone);
2070  out_destroy_ifork_zone:
2071 	kmem_cache_destroy(xfs_ifork_zone);
2072  out_destroy_da_state_zone:
2073 	kmem_cache_destroy(xfs_da_state_zone);
2074  out_destroy_btree_cur_zone:
2075 	kmem_cache_destroy(xfs_btree_cur_zone);
2076  out_destroy_bmap_free_item_zone:
2077 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2078  out_destroy_log_ticket_zone:
2079 	kmem_cache_destroy(xfs_log_ticket_zone);
2080  out:
2081 	return -ENOMEM;
2082 }
2083 
2084 STATIC void
2085 xfs_destroy_zones(void)
2086 {
2087 	/*
2088 	 * Make sure all delayed rcu free are flushed before we
2089 	 * destroy caches.
2090 	 */
2091 	rcu_barrier();
2092 	kmem_cache_destroy(xfs_bui_zone);
2093 	kmem_cache_destroy(xfs_bud_zone);
2094 	kmem_cache_destroy(xfs_cui_zone);
2095 	kmem_cache_destroy(xfs_cud_zone);
2096 	kmem_cache_destroy(xfs_rui_zone);
2097 	kmem_cache_destroy(xfs_rud_zone);
2098 	kmem_cache_destroy(xfs_icreate_zone);
2099 	kmem_cache_destroy(xfs_ili_zone);
2100 	kmem_cache_destroy(xfs_inode_zone);
2101 	kmem_cache_destroy(xfs_efi_zone);
2102 	kmem_cache_destroy(xfs_efd_zone);
2103 	kmem_cache_destroy(xfs_buf_item_zone);
2104 	kmem_cache_destroy(xfs_trans_zone);
2105 	kmem_cache_destroy(xfs_ifork_zone);
2106 	kmem_cache_destroy(xfs_da_state_zone);
2107 	kmem_cache_destroy(xfs_btree_cur_zone);
2108 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2109 	kmem_cache_destroy(xfs_log_ticket_zone);
2110 }
2111 
2112 STATIC int __init
2113 xfs_init_workqueues(void)
2114 {
2115 	/*
2116 	 * The allocation workqueue can be used in memory reclaim situations
2117 	 * (writepage path), and parallelism is only limited by the number of
2118 	 * AGs in all the filesystems mounted. Hence use the default large
2119 	 * max_active value for this workqueue.
2120 	 */
2121 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2122 			WQ_MEM_RECLAIM|WQ_FREEZABLE, 0);
2123 	if (!xfs_alloc_wq)
2124 		return -ENOMEM;
2125 
2126 	xfs_discard_wq = alloc_workqueue("xfsdiscard", WQ_UNBOUND, 0);
2127 	if (!xfs_discard_wq)
2128 		goto out_free_alloc_wq;
2129 
2130 	return 0;
2131 out_free_alloc_wq:
2132 	destroy_workqueue(xfs_alloc_wq);
2133 	return -ENOMEM;
2134 }
2135 
2136 STATIC void
2137 xfs_destroy_workqueues(void)
2138 {
2139 	destroy_workqueue(xfs_discard_wq);
2140 	destroy_workqueue(xfs_alloc_wq);
2141 }
2142 
2143 STATIC int __init
2144 init_xfs_fs(void)
2145 {
2146 	int			error;
2147 
2148 	xfs_check_ondisk_structs();
2149 
2150 	printk(KERN_INFO XFS_VERSION_STRING " with "
2151 			 XFS_BUILD_OPTIONS " enabled\n");
2152 
2153 	xfs_dir_startup();
2154 
2155 	error = xfs_init_zones();
2156 	if (error)
2157 		goto out;
2158 
2159 	error = xfs_init_workqueues();
2160 	if (error)
2161 		goto out_destroy_zones;
2162 
2163 	error = xfs_mru_cache_init();
2164 	if (error)
2165 		goto out_destroy_wq;
2166 
2167 	error = xfs_buf_init();
2168 	if (error)
2169 		goto out_mru_cache_uninit;
2170 
2171 	error = xfs_init_procfs();
2172 	if (error)
2173 		goto out_buf_terminate;
2174 
2175 	error = xfs_sysctl_register();
2176 	if (error)
2177 		goto out_cleanup_procfs;
2178 
2179 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2180 	if (!xfs_kset) {
2181 		error = -ENOMEM;
2182 		goto out_sysctl_unregister;
2183 	}
2184 
2185 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2186 
2187 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2188 	if (!xfsstats.xs_stats) {
2189 		error = -ENOMEM;
2190 		goto out_kset_unregister;
2191 	}
2192 
2193 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2194 			       "stats");
2195 	if (error)
2196 		goto out_free_stats;
2197 
2198 #ifdef DEBUG
2199 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2200 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2201 	if (error)
2202 		goto out_remove_stats_kobj;
2203 #endif
2204 
2205 	error = xfs_qm_init();
2206 	if (error)
2207 		goto out_remove_dbg_kobj;
2208 
2209 	error = register_filesystem(&xfs_fs_type);
2210 	if (error)
2211 		goto out_qm_exit;
2212 	return 0;
2213 
2214  out_qm_exit:
2215 	xfs_qm_exit();
2216  out_remove_dbg_kobj:
2217 #ifdef DEBUG
2218 	xfs_sysfs_del(&xfs_dbg_kobj);
2219  out_remove_stats_kobj:
2220 #endif
2221 	xfs_sysfs_del(&xfsstats.xs_kobj);
2222  out_free_stats:
2223 	free_percpu(xfsstats.xs_stats);
2224  out_kset_unregister:
2225 	kset_unregister(xfs_kset);
2226  out_sysctl_unregister:
2227 	xfs_sysctl_unregister();
2228  out_cleanup_procfs:
2229 	xfs_cleanup_procfs();
2230  out_buf_terminate:
2231 	xfs_buf_terminate();
2232  out_mru_cache_uninit:
2233 	xfs_mru_cache_uninit();
2234  out_destroy_wq:
2235 	xfs_destroy_workqueues();
2236  out_destroy_zones:
2237 	xfs_destroy_zones();
2238  out:
2239 	return error;
2240 }
2241 
2242 STATIC void __exit
2243 exit_xfs_fs(void)
2244 {
2245 	xfs_qm_exit();
2246 	unregister_filesystem(&xfs_fs_type);
2247 #ifdef DEBUG
2248 	xfs_sysfs_del(&xfs_dbg_kobj);
2249 #endif
2250 	xfs_sysfs_del(&xfsstats.xs_kobj);
2251 	free_percpu(xfsstats.xs_stats);
2252 	kset_unregister(xfs_kset);
2253 	xfs_sysctl_unregister();
2254 	xfs_cleanup_procfs();
2255 	xfs_buf_terminate();
2256 	xfs_mru_cache_uninit();
2257 	xfs_destroy_workqueues();
2258 	xfs_destroy_zones();
2259 	xfs_uuid_table_free();
2260 }
2261 
2262 module_init(init_xfs_fs);
2263 module_exit(exit_xfs_fs);
2264 
2265 MODULE_AUTHOR("Silicon Graphics, Inc.");
2266 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2267 MODULE_LICENSE("GPL");
2268