xref: /linux/fs/xfs/xfs_super.c (revision 81361b837a3450f0a44255fddfd7a4c72502b667)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 
7 #include "xfs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_sb.h"
13 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_btree.h"
16 #include "xfs_bmap.h"
17 #include "xfs_alloc.h"
18 #include "xfs_fsops.h"
19 #include "xfs_trans.h"
20 #include "xfs_buf_item.h"
21 #include "xfs_log.h"
22 #include "xfs_log_priv.h"
23 #include "xfs_dir2.h"
24 #include "xfs_extfree_item.h"
25 #include "xfs_mru_cache.h"
26 #include "xfs_inode_item.h"
27 #include "xfs_icache.h"
28 #include "xfs_trace.h"
29 #include "xfs_icreate_item.h"
30 #include "xfs_filestream.h"
31 #include "xfs_quota.h"
32 #include "xfs_sysfs.h"
33 #include "xfs_ondisk.h"
34 #include "xfs_rmap_item.h"
35 #include "xfs_refcount_item.h"
36 #include "xfs_bmap_item.h"
37 #include "xfs_reflink.h"
38 #include "xfs_pwork.h"
39 #include "xfs_ag.h"
40 
41 #include <linux/magic.h>
42 #include <linux/fs_context.h>
43 #include <linux/fs_parser.h>
44 
45 static const struct super_operations xfs_super_operations;
46 
47 static struct kset *xfs_kset;		/* top-level xfs sysfs dir */
48 #ifdef DEBUG
49 static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
50 #endif
51 
52 enum xfs_dax_mode {
53 	XFS_DAX_INODE = 0,
54 	XFS_DAX_ALWAYS = 1,
55 	XFS_DAX_NEVER = 2,
56 };
57 
58 static void
59 xfs_mount_set_dax_mode(
60 	struct xfs_mount	*mp,
61 	enum xfs_dax_mode	mode)
62 {
63 	switch (mode) {
64 	case XFS_DAX_INODE:
65 		mp->m_flags &= ~(XFS_MOUNT_DAX_ALWAYS | XFS_MOUNT_DAX_NEVER);
66 		break;
67 	case XFS_DAX_ALWAYS:
68 		mp->m_flags |= XFS_MOUNT_DAX_ALWAYS;
69 		mp->m_flags &= ~XFS_MOUNT_DAX_NEVER;
70 		break;
71 	case XFS_DAX_NEVER:
72 		mp->m_flags |= XFS_MOUNT_DAX_NEVER;
73 		mp->m_flags &= ~XFS_MOUNT_DAX_ALWAYS;
74 		break;
75 	}
76 }
77 
78 static const struct constant_table dax_param_enums[] = {
79 	{"inode",	XFS_DAX_INODE },
80 	{"always",	XFS_DAX_ALWAYS },
81 	{"never",	XFS_DAX_NEVER },
82 	{}
83 };
84 
85 /*
86  * Table driven mount option parser.
87  */
88 enum {
89 	Opt_logbufs, Opt_logbsize, Opt_logdev, Opt_rtdev,
90 	Opt_wsync, Opt_noalign, Opt_swalloc, Opt_sunit, Opt_swidth, Opt_nouuid,
91 	Opt_grpid, Opt_nogrpid, Opt_bsdgroups, Opt_sysvgroups,
92 	Opt_allocsize, Opt_norecovery, Opt_inode64, Opt_inode32, Opt_ikeep,
93 	Opt_noikeep, Opt_largeio, Opt_nolargeio, Opt_attr2, Opt_noattr2,
94 	Opt_filestreams, Opt_quota, Opt_noquota, Opt_usrquota, Opt_grpquota,
95 	Opt_prjquota, Opt_uquota, Opt_gquota, Opt_pquota,
96 	Opt_uqnoenforce, Opt_gqnoenforce, Opt_pqnoenforce, Opt_qnoenforce,
97 	Opt_discard, Opt_nodiscard, Opt_dax, Opt_dax_enum,
98 };
99 
100 static const struct fs_parameter_spec xfs_fs_parameters[] = {
101 	fsparam_u32("logbufs",		Opt_logbufs),
102 	fsparam_string("logbsize",	Opt_logbsize),
103 	fsparam_string("logdev",	Opt_logdev),
104 	fsparam_string("rtdev",		Opt_rtdev),
105 	fsparam_flag("wsync",		Opt_wsync),
106 	fsparam_flag("noalign",		Opt_noalign),
107 	fsparam_flag("swalloc",		Opt_swalloc),
108 	fsparam_u32("sunit",		Opt_sunit),
109 	fsparam_u32("swidth",		Opt_swidth),
110 	fsparam_flag("nouuid",		Opt_nouuid),
111 	fsparam_flag("grpid",		Opt_grpid),
112 	fsparam_flag("nogrpid",		Opt_nogrpid),
113 	fsparam_flag("bsdgroups",	Opt_bsdgroups),
114 	fsparam_flag("sysvgroups",	Opt_sysvgroups),
115 	fsparam_string("allocsize",	Opt_allocsize),
116 	fsparam_flag("norecovery",	Opt_norecovery),
117 	fsparam_flag("inode64",		Opt_inode64),
118 	fsparam_flag("inode32",		Opt_inode32),
119 	fsparam_flag("ikeep",		Opt_ikeep),
120 	fsparam_flag("noikeep",		Opt_noikeep),
121 	fsparam_flag("largeio",		Opt_largeio),
122 	fsparam_flag("nolargeio",	Opt_nolargeio),
123 	fsparam_flag("attr2",		Opt_attr2),
124 	fsparam_flag("noattr2",		Opt_noattr2),
125 	fsparam_flag("filestreams",	Opt_filestreams),
126 	fsparam_flag("quota",		Opt_quota),
127 	fsparam_flag("noquota",		Opt_noquota),
128 	fsparam_flag("usrquota",	Opt_usrquota),
129 	fsparam_flag("grpquota",	Opt_grpquota),
130 	fsparam_flag("prjquota",	Opt_prjquota),
131 	fsparam_flag("uquota",		Opt_uquota),
132 	fsparam_flag("gquota",		Opt_gquota),
133 	fsparam_flag("pquota",		Opt_pquota),
134 	fsparam_flag("uqnoenforce",	Opt_uqnoenforce),
135 	fsparam_flag("gqnoenforce",	Opt_gqnoenforce),
136 	fsparam_flag("pqnoenforce",	Opt_pqnoenforce),
137 	fsparam_flag("qnoenforce",	Opt_qnoenforce),
138 	fsparam_flag("discard",		Opt_discard),
139 	fsparam_flag("nodiscard",	Opt_nodiscard),
140 	fsparam_flag("dax",		Opt_dax),
141 	fsparam_enum("dax",		Opt_dax_enum, dax_param_enums),
142 	{}
143 };
144 
145 struct proc_xfs_info {
146 	uint64_t	flag;
147 	char		*str;
148 };
149 
150 static int
151 xfs_fs_show_options(
152 	struct seq_file		*m,
153 	struct dentry		*root)
154 {
155 	static struct proc_xfs_info xfs_info_set[] = {
156 		/* the few simple ones we can get from the mount struct */
157 		{ XFS_MOUNT_IKEEP,		",ikeep" },
158 		{ XFS_MOUNT_WSYNC,		",wsync" },
159 		{ XFS_MOUNT_NOALIGN,		",noalign" },
160 		{ XFS_MOUNT_SWALLOC,		",swalloc" },
161 		{ XFS_MOUNT_NOUUID,		",nouuid" },
162 		{ XFS_MOUNT_NORECOVERY,		",norecovery" },
163 		{ XFS_MOUNT_ATTR2,		",attr2" },
164 		{ XFS_MOUNT_FILESTREAMS,	",filestreams" },
165 		{ XFS_MOUNT_GRPID,		",grpid" },
166 		{ XFS_MOUNT_DISCARD,		",discard" },
167 		{ XFS_MOUNT_LARGEIO,		",largeio" },
168 		{ XFS_MOUNT_DAX_ALWAYS,		",dax=always" },
169 		{ XFS_MOUNT_DAX_NEVER,		",dax=never" },
170 		{ 0, NULL }
171 	};
172 	struct xfs_mount	*mp = XFS_M(root->d_sb);
173 	struct proc_xfs_info	*xfs_infop;
174 
175 	for (xfs_infop = xfs_info_set; xfs_infop->flag; xfs_infop++) {
176 		if (mp->m_flags & xfs_infop->flag)
177 			seq_puts(m, xfs_infop->str);
178 	}
179 
180 	seq_printf(m, ",inode%d",
181 		(mp->m_flags & XFS_MOUNT_SMALL_INUMS) ? 32 : 64);
182 
183 	if (mp->m_flags & XFS_MOUNT_ALLOCSIZE)
184 		seq_printf(m, ",allocsize=%dk",
185 			   (1 << mp->m_allocsize_log) >> 10);
186 
187 	if (mp->m_logbufs > 0)
188 		seq_printf(m, ",logbufs=%d", mp->m_logbufs);
189 	if (mp->m_logbsize > 0)
190 		seq_printf(m, ",logbsize=%dk", mp->m_logbsize >> 10);
191 
192 	if (mp->m_logname)
193 		seq_show_option(m, "logdev", mp->m_logname);
194 	if (mp->m_rtname)
195 		seq_show_option(m, "rtdev", mp->m_rtname);
196 
197 	if (mp->m_dalign > 0)
198 		seq_printf(m, ",sunit=%d",
199 				(int)XFS_FSB_TO_BB(mp, mp->m_dalign));
200 	if (mp->m_swidth > 0)
201 		seq_printf(m, ",swidth=%d",
202 				(int)XFS_FSB_TO_BB(mp, mp->m_swidth));
203 
204 	if (mp->m_qflags & XFS_UQUOTA_ACCT) {
205 		if (mp->m_qflags & XFS_UQUOTA_ENFD)
206 			seq_puts(m, ",usrquota");
207 		else
208 			seq_puts(m, ",uqnoenforce");
209 	}
210 
211 	if (mp->m_qflags & XFS_PQUOTA_ACCT) {
212 		if (mp->m_qflags & XFS_PQUOTA_ENFD)
213 			seq_puts(m, ",prjquota");
214 		else
215 			seq_puts(m, ",pqnoenforce");
216 	}
217 	if (mp->m_qflags & XFS_GQUOTA_ACCT) {
218 		if (mp->m_qflags & XFS_GQUOTA_ENFD)
219 			seq_puts(m, ",grpquota");
220 		else
221 			seq_puts(m, ",gqnoenforce");
222 	}
223 
224 	if (!(mp->m_qflags & XFS_ALL_QUOTA_ACCT))
225 		seq_puts(m, ",noquota");
226 
227 	return 0;
228 }
229 
230 /*
231  * Set parameters for inode allocation heuristics, taking into account
232  * filesystem size and inode32/inode64 mount options; i.e. specifically
233  * whether or not XFS_MOUNT_SMALL_INUMS is set.
234  *
235  * Inode allocation patterns are altered only if inode32 is requested
236  * (XFS_MOUNT_SMALL_INUMS), and the filesystem is sufficiently large.
237  * If altered, XFS_MOUNT_32BITINODES is set as well.
238  *
239  * An agcount independent of that in the mount structure is provided
240  * because in the growfs case, mp->m_sb.sb_agcount is not yet updated
241  * to the potentially higher ag count.
242  *
243  * Returns the maximum AG index which may contain inodes.
244  */
245 xfs_agnumber_t
246 xfs_set_inode_alloc(
247 	struct xfs_mount *mp,
248 	xfs_agnumber_t	agcount)
249 {
250 	xfs_agnumber_t	index;
251 	xfs_agnumber_t	maxagi = 0;
252 	xfs_sb_t	*sbp = &mp->m_sb;
253 	xfs_agnumber_t	max_metadata;
254 	xfs_agino_t	agino;
255 	xfs_ino_t	ino;
256 
257 	/*
258 	 * Calculate how much should be reserved for inodes to meet
259 	 * the max inode percentage.  Used only for inode32.
260 	 */
261 	if (M_IGEO(mp)->maxicount) {
262 		uint64_t	icount;
263 
264 		icount = sbp->sb_dblocks * sbp->sb_imax_pct;
265 		do_div(icount, 100);
266 		icount += sbp->sb_agblocks - 1;
267 		do_div(icount, sbp->sb_agblocks);
268 		max_metadata = icount;
269 	} else {
270 		max_metadata = agcount;
271 	}
272 
273 	/* Get the last possible inode in the filesystem */
274 	agino =	XFS_AGB_TO_AGINO(mp, sbp->sb_agblocks - 1);
275 	ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
276 
277 	/*
278 	 * If user asked for no more than 32-bit inodes, and the fs is
279 	 * sufficiently large, set XFS_MOUNT_32BITINODES if we must alter
280 	 * the allocator to accommodate the request.
281 	 */
282 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > XFS_MAXINUMBER_32)
283 		mp->m_flags |= XFS_MOUNT_32BITINODES;
284 	else
285 		mp->m_flags &= ~XFS_MOUNT_32BITINODES;
286 
287 	for (index = 0; index < agcount; index++) {
288 		struct xfs_perag	*pag;
289 
290 		ino = XFS_AGINO_TO_INO(mp, index, agino);
291 
292 		pag = xfs_perag_get(mp, index);
293 
294 		if (mp->m_flags & XFS_MOUNT_32BITINODES) {
295 			if (ino > XFS_MAXINUMBER_32) {
296 				pag->pagi_inodeok = 0;
297 				pag->pagf_metadata = 0;
298 			} else {
299 				pag->pagi_inodeok = 1;
300 				maxagi++;
301 				if (index < max_metadata)
302 					pag->pagf_metadata = 1;
303 				else
304 					pag->pagf_metadata = 0;
305 			}
306 		} else {
307 			pag->pagi_inodeok = 1;
308 			pag->pagf_metadata = 0;
309 		}
310 
311 		xfs_perag_put(pag);
312 	}
313 
314 	return (mp->m_flags & XFS_MOUNT_32BITINODES) ? maxagi : agcount;
315 }
316 
317 STATIC int
318 xfs_blkdev_get(
319 	xfs_mount_t		*mp,
320 	const char		*name,
321 	struct block_device	**bdevp)
322 {
323 	int			error = 0;
324 
325 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
326 				    mp);
327 	if (IS_ERR(*bdevp)) {
328 		error = PTR_ERR(*bdevp);
329 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
330 	}
331 
332 	return error;
333 }
334 
335 STATIC void
336 xfs_blkdev_put(
337 	struct block_device	*bdev)
338 {
339 	if (bdev)
340 		blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
341 }
342 
343 STATIC void
344 xfs_close_devices(
345 	struct xfs_mount	*mp)
346 {
347 	struct dax_device *dax_ddev = mp->m_ddev_targp->bt_daxdev;
348 
349 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
350 		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
351 		struct dax_device *dax_logdev = mp->m_logdev_targp->bt_daxdev;
352 
353 		xfs_free_buftarg(mp->m_logdev_targp);
354 		xfs_blkdev_put(logdev);
355 		fs_put_dax(dax_logdev);
356 	}
357 	if (mp->m_rtdev_targp) {
358 		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
359 		struct dax_device *dax_rtdev = mp->m_rtdev_targp->bt_daxdev;
360 
361 		xfs_free_buftarg(mp->m_rtdev_targp);
362 		xfs_blkdev_put(rtdev);
363 		fs_put_dax(dax_rtdev);
364 	}
365 	xfs_free_buftarg(mp->m_ddev_targp);
366 	fs_put_dax(dax_ddev);
367 }
368 
369 /*
370  * The file system configurations are:
371  *	(1) device (partition) with data and internal log
372  *	(2) logical volume with data and log subvolumes.
373  *	(3) logical volume with data, log, and realtime subvolumes.
374  *
375  * We only have to handle opening the log and realtime volumes here if
376  * they are present.  The data subvolume has already been opened by
377  * get_sb_bdev() and is stored in sb->s_bdev.
378  */
379 STATIC int
380 xfs_open_devices(
381 	struct xfs_mount	*mp)
382 {
383 	struct block_device	*ddev = mp->m_super->s_bdev;
384 	struct dax_device	*dax_ddev = fs_dax_get_by_bdev(ddev);
385 	struct dax_device	*dax_logdev = NULL, *dax_rtdev = NULL;
386 	struct block_device	*logdev = NULL, *rtdev = NULL;
387 	int			error;
388 
389 	/*
390 	 * Open real time and log devices - order is important.
391 	 */
392 	if (mp->m_logname) {
393 		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
394 		if (error)
395 			goto out;
396 		dax_logdev = fs_dax_get_by_bdev(logdev);
397 	}
398 
399 	if (mp->m_rtname) {
400 		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
401 		if (error)
402 			goto out_close_logdev;
403 
404 		if (rtdev == ddev || rtdev == logdev) {
405 			xfs_warn(mp,
406 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
407 			error = -EINVAL;
408 			goto out_close_rtdev;
409 		}
410 		dax_rtdev = fs_dax_get_by_bdev(rtdev);
411 	}
412 
413 	/*
414 	 * Setup xfs_mount buffer target pointers
415 	 */
416 	error = -ENOMEM;
417 	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev, dax_ddev);
418 	if (!mp->m_ddev_targp)
419 		goto out_close_rtdev;
420 
421 	if (rtdev) {
422 		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev, dax_rtdev);
423 		if (!mp->m_rtdev_targp)
424 			goto out_free_ddev_targ;
425 	}
426 
427 	if (logdev && logdev != ddev) {
428 		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev, dax_logdev);
429 		if (!mp->m_logdev_targp)
430 			goto out_free_rtdev_targ;
431 	} else {
432 		mp->m_logdev_targp = mp->m_ddev_targp;
433 	}
434 
435 	return 0;
436 
437  out_free_rtdev_targ:
438 	if (mp->m_rtdev_targp)
439 		xfs_free_buftarg(mp->m_rtdev_targp);
440  out_free_ddev_targ:
441 	xfs_free_buftarg(mp->m_ddev_targp);
442  out_close_rtdev:
443 	xfs_blkdev_put(rtdev);
444 	fs_put_dax(dax_rtdev);
445  out_close_logdev:
446 	if (logdev && logdev != ddev) {
447 		xfs_blkdev_put(logdev);
448 		fs_put_dax(dax_logdev);
449 	}
450  out:
451 	fs_put_dax(dax_ddev);
452 	return error;
453 }
454 
455 /*
456  * Setup xfs_mount buffer target pointers based on superblock
457  */
458 STATIC int
459 xfs_setup_devices(
460 	struct xfs_mount	*mp)
461 {
462 	int			error;
463 
464 	error = xfs_setsize_buftarg(mp->m_ddev_targp, mp->m_sb.sb_sectsize);
465 	if (error)
466 		return error;
467 
468 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
469 		unsigned int	log_sector_size = BBSIZE;
470 
471 		if (xfs_sb_version_hassector(&mp->m_sb))
472 			log_sector_size = mp->m_sb.sb_logsectsize;
473 		error = xfs_setsize_buftarg(mp->m_logdev_targp,
474 					    log_sector_size);
475 		if (error)
476 			return error;
477 	}
478 	if (mp->m_rtdev_targp) {
479 		error = xfs_setsize_buftarg(mp->m_rtdev_targp,
480 					    mp->m_sb.sb_sectsize);
481 		if (error)
482 			return error;
483 	}
484 
485 	return 0;
486 }
487 
488 STATIC int
489 xfs_init_mount_workqueues(
490 	struct xfs_mount	*mp)
491 {
492 	mp->m_buf_workqueue = alloc_workqueue("xfs-buf/%s",
493 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
494 			1, mp->m_super->s_id);
495 	if (!mp->m_buf_workqueue)
496 		goto out;
497 
498 	mp->m_unwritten_workqueue = alloc_workqueue("xfs-conv/%s",
499 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
500 			0, mp->m_super->s_id);
501 	if (!mp->m_unwritten_workqueue)
502 		goto out_destroy_buf;
503 
504 	mp->m_cil_workqueue = alloc_workqueue("xfs-cil/%s",
505 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM | WQ_UNBOUND),
506 			0, mp->m_super->s_id);
507 	if (!mp->m_cil_workqueue)
508 		goto out_destroy_unwritten;
509 
510 	mp->m_reclaim_workqueue = alloc_workqueue("xfs-reclaim/%s",
511 			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
512 			0, mp->m_super->s_id);
513 	if (!mp->m_reclaim_workqueue)
514 		goto out_destroy_cil;
515 
516 	mp->m_gc_workqueue = alloc_workqueue("xfs-gc/%s",
517 			WQ_SYSFS | WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM,
518 			0, mp->m_super->s_id);
519 	if (!mp->m_gc_workqueue)
520 		goto out_destroy_reclaim;
521 
522 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
523 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
524 	if (!mp->m_sync_workqueue)
525 		goto out_destroy_eofb;
526 
527 	return 0;
528 
529 out_destroy_eofb:
530 	destroy_workqueue(mp->m_gc_workqueue);
531 out_destroy_reclaim:
532 	destroy_workqueue(mp->m_reclaim_workqueue);
533 out_destroy_cil:
534 	destroy_workqueue(mp->m_cil_workqueue);
535 out_destroy_unwritten:
536 	destroy_workqueue(mp->m_unwritten_workqueue);
537 out_destroy_buf:
538 	destroy_workqueue(mp->m_buf_workqueue);
539 out:
540 	return -ENOMEM;
541 }
542 
543 STATIC void
544 xfs_destroy_mount_workqueues(
545 	struct xfs_mount	*mp)
546 {
547 	destroy_workqueue(mp->m_sync_workqueue);
548 	destroy_workqueue(mp->m_gc_workqueue);
549 	destroy_workqueue(mp->m_reclaim_workqueue);
550 	destroy_workqueue(mp->m_cil_workqueue);
551 	destroy_workqueue(mp->m_unwritten_workqueue);
552 	destroy_workqueue(mp->m_buf_workqueue);
553 }
554 
555 static void
556 xfs_flush_inodes_worker(
557 	struct work_struct	*work)
558 {
559 	struct xfs_mount	*mp = container_of(work, struct xfs_mount,
560 						   m_flush_inodes_work);
561 	struct super_block	*sb = mp->m_super;
562 
563 	if (down_read_trylock(&sb->s_umount)) {
564 		sync_inodes_sb(sb);
565 		up_read(&sb->s_umount);
566 	}
567 }
568 
569 /*
570  * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
571  * or a page lock. We use sync_inodes_sb() here to ensure we block while waiting
572  * for IO to complete so that we effectively throttle multiple callers to the
573  * rate at which IO is completing.
574  */
575 void
576 xfs_flush_inodes(
577 	struct xfs_mount	*mp)
578 {
579 	/*
580 	 * If flush_work() returns true then that means we waited for a flush
581 	 * which was already in progress.  Don't bother running another scan.
582 	 */
583 	if (flush_work(&mp->m_flush_inodes_work))
584 		return;
585 
586 	queue_work(mp->m_sync_workqueue, &mp->m_flush_inodes_work);
587 	flush_work(&mp->m_flush_inodes_work);
588 }
589 
590 /* Catch misguided souls that try to use this interface on XFS */
591 STATIC struct inode *
592 xfs_fs_alloc_inode(
593 	struct super_block	*sb)
594 {
595 	BUG();
596 	return NULL;
597 }
598 
599 #ifdef DEBUG
600 static void
601 xfs_check_delalloc(
602 	struct xfs_inode	*ip,
603 	int			whichfork)
604 {
605 	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, whichfork);
606 	struct xfs_bmbt_irec	got;
607 	struct xfs_iext_cursor	icur;
608 
609 	if (!ifp || !xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got))
610 		return;
611 	do {
612 		if (isnullstartblock(got.br_startblock)) {
613 			xfs_warn(ip->i_mount,
614 	"ino %llx %s fork has delalloc extent at [0x%llx:0x%llx]",
615 				ip->i_ino,
616 				whichfork == XFS_DATA_FORK ? "data" : "cow",
617 				got.br_startoff, got.br_blockcount);
618 		}
619 	} while (xfs_iext_next_extent(ifp, &icur, &got));
620 }
621 #else
622 #define xfs_check_delalloc(ip, whichfork)	do { } while (0)
623 #endif
624 
625 /*
626  * Now that the generic code is guaranteed not to be accessing
627  * the linux inode, we can inactivate and reclaim the inode.
628  */
629 STATIC void
630 xfs_fs_destroy_inode(
631 	struct inode		*inode)
632 {
633 	struct xfs_inode	*ip = XFS_I(inode);
634 
635 	trace_xfs_destroy_inode(ip);
636 
637 	ASSERT(!rwsem_is_locked(&inode->i_rwsem));
638 	XFS_STATS_INC(ip->i_mount, vn_rele);
639 	XFS_STATS_INC(ip->i_mount, vn_remove);
640 
641 	xfs_inactive(ip);
642 
643 	if (!XFS_FORCED_SHUTDOWN(ip->i_mount) && ip->i_delayed_blks) {
644 		xfs_check_delalloc(ip, XFS_DATA_FORK);
645 		xfs_check_delalloc(ip, XFS_COW_FORK);
646 		ASSERT(0);
647 	}
648 
649 	XFS_STATS_INC(ip->i_mount, vn_reclaim);
650 
651 	/*
652 	 * We should never get here with one of the reclaim flags already set.
653 	 */
654 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIMABLE));
655 	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIM));
656 
657 	/*
658 	 * We always use background reclaim here because even if the inode is
659 	 * clean, it still may be under IO and hence we have wait for IO
660 	 * completion to occur before we can reclaim the inode. The background
661 	 * reclaim path handles this more efficiently than we can here, so
662 	 * simply let background reclaim tear down all inodes.
663 	 */
664 	xfs_inode_mark_reclaimable(ip);
665 }
666 
667 static void
668 xfs_fs_dirty_inode(
669 	struct inode			*inode,
670 	int				flag)
671 {
672 	struct xfs_inode		*ip = XFS_I(inode);
673 	struct xfs_mount		*mp = ip->i_mount;
674 	struct xfs_trans		*tp;
675 
676 	if (!(inode->i_sb->s_flags & SB_LAZYTIME))
677 		return;
678 	if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME))
679 		return;
680 
681 	if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp))
682 		return;
683 	xfs_ilock(ip, XFS_ILOCK_EXCL);
684 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
685 	xfs_trans_log_inode(tp, ip, XFS_ILOG_TIMESTAMP);
686 	xfs_trans_commit(tp);
687 }
688 
689 /*
690  * Slab object creation initialisation for the XFS inode.
691  * This covers only the idempotent fields in the XFS inode;
692  * all other fields need to be initialised on allocation
693  * from the slab. This avoids the need to repeatedly initialise
694  * fields in the xfs inode that left in the initialise state
695  * when freeing the inode.
696  */
697 STATIC void
698 xfs_fs_inode_init_once(
699 	void			*inode)
700 {
701 	struct xfs_inode	*ip = inode;
702 
703 	memset(ip, 0, sizeof(struct xfs_inode));
704 
705 	/* vfs inode */
706 	inode_init_once(VFS_I(ip));
707 
708 	/* xfs inode */
709 	atomic_set(&ip->i_pincount, 0);
710 	spin_lock_init(&ip->i_flags_lock);
711 
712 	mrlock_init(&ip->i_mmaplock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
713 		     "xfsino", ip->i_ino);
714 	mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER,
715 		     "xfsino", ip->i_ino);
716 }
717 
718 /*
719  * We do an unlocked check for XFS_IDONTCACHE here because we are already
720  * serialised against cache hits here via the inode->i_lock and igrab() in
721  * xfs_iget_cache_hit(). Hence a lookup that might clear this flag will not be
722  * racing with us, and it avoids needing to grab a spinlock here for every inode
723  * we drop the final reference on.
724  */
725 STATIC int
726 xfs_fs_drop_inode(
727 	struct inode		*inode)
728 {
729 	struct xfs_inode	*ip = XFS_I(inode);
730 
731 	/*
732 	 * If this unlinked inode is in the middle of recovery, don't
733 	 * drop the inode just yet; log recovery will take care of
734 	 * that.  See the comment for this inode flag.
735 	 */
736 	if (ip->i_flags & XFS_IRECOVERY) {
737 		ASSERT(ip->i_mount->m_log->l_flags & XLOG_RECOVERY_NEEDED);
738 		return 0;
739 	}
740 
741 	return generic_drop_inode(inode);
742 }
743 
744 static void
745 xfs_mount_free(
746 	struct xfs_mount	*mp)
747 {
748 	kfree(mp->m_rtname);
749 	kfree(mp->m_logname);
750 	kmem_free(mp);
751 }
752 
753 STATIC int
754 xfs_fs_sync_fs(
755 	struct super_block	*sb,
756 	int			wait)
757 {
758 	struct xfs_mount	*mp = XFS_M(sb);
759 
760 	/*
761 	 * Doing anything during the async pass would be counterproductive.
762 	 */
763 	if (!wait)
764 		return 0;
765 
766 	xfs_log_force(mp, XFS_LOG_SYNC);
767 	if (laptop_mode) {
768 		/*
769 		 * The disk must be active because we're syncing.
770 		 * We schedule log work now (now that the disk is
771 		 * active) instead of later (when it might not be).
772 		 */
773 		flush_delayed_work(&mp->m_log->l_work);
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 	statp->f_type = XFS_SUPER_MAGIC;
795 	statp->f_namelen = MAXNAMELEN - 1;
796 
797 	id = huge_encode_dev(mp->m_ddev_targp->bt_dev);
798 	statp->f_fsid = u64_to_fsid(id);
799 
800 	icount = percpu_counter_sum(&mp->m_icount);
801 	ifree = percpu_counter_sum(&mp->m_ifree);
802 	fdblocks = percpu_counter_sum(&mp->m_fdblocks);
803 
804 	spin_lock(&mp->m_sb_lock);
805 	statp->f_bsize = sbp->sb_blocksize;
806 	lsize = sbp->sb_logstart ? sbp->sb_logblocks : 0;
807 	statp->f_blocks = sbp->sb_dblocks - lsize;
808 	spin_unlock(&mp->m_sb_lock);
809 
810 	/* make sure statp->f_bfree does not underflow */
811 	statp->f_bfree = max_t(int64_t, fdblocks - mp->m_alloc_set_aside, 0);
812 	statp->f_bavail = statp->f_bfree;
813 
814 	fakeinos = XFS_FSB_TO_INO(mp, statp->f_bfree);
815 	statp->f_files = min(icount + fakeinos, (uint64_t)XFS_MAXINUMBER);
816 	if (M_IGEO(mp)->maxicount)
817 		statp->f_files = min_t(typeof(statp->f_files),
818 					statp->f_files,
819 					M_IGEO(mp)->maxicount);
820 
821 	/* If sb_icount overshot maxicount, report actual allocation */
822 	statp->f_files = max_t(typeof(statp->f_files),
823 					statp->f_files,
824 					sbp->sb_icount);
825 
826 	/* make sure statp->f_ffree does not underflow */
827 	ffree = statp->f_files - (icount - ifree);
828 	statp->f_ffree = max_t(int64_t, ffree, 0);
829 
830 
831 	if ((ip->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
832 	    ((mp->m_qflags & (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))) ==
833 			      (XFS_PQUOTA_ACCT|XFS_PQUOTA_ENFD))
834 		xfs_qm_statvfs(ip, statp);
835 
836 	if (XFS_IS_REALTIME_MOUNT(mp) &&
837 	    (ip->i_diflags & (XFS_DIFLAG_RTINHERIT | XFS_DIFLAG_REALTIME))) {
838 		statp->f_blocks = sbp->sb_rblocks;
839 		statp->f_bavail = statp->f_bfree =
840 			sbp->sb_frextents * sbp->sb_rextsize;
841 	}
842 
843 	return 0;
844 }
845 
846 STATIC void
847 xfs_save_resvblks(struct xfs_mount *mp)
848 {
849 	uint64_t resblks = 0;
850 
851 	mp->m_resblks_save = mp->m_resblks;
852 	xfs_reserve_blocks(mp, &resblks, NULL);
853 }
854 
855 STATIC void
856 xfs_restore_resvblks(struct xfs_mount *mp)
857 {
858 	uint64_t resblks;
859 
860 	if (mp->m_resblks_save) {
861 		resblks = mp->m_resblks_save;
862 		mp->m_resblks_save = 0;
863 	} else
864 		resblks = xfs_default_resblks(mp);
865 
866 	xfs_reserve_blocks(mp, &resblks, NULL);
867 }
868 
869 /*
870  * Second stage of a freeze. The data is already frozen so we only
871  * need to take care of the metadata. Once that's done sync the superblock
872  * to the log to dirty it in case of a crash while frozen. This ensures that we
873  * will recover the unlinked inode lists on the next mount.
874  */
875 STATIC int
876 xfs_fs_freeze(
877 	struct super_block	*sb)
878 {
879 	struct xfs_mount	*mp = XFS_M(sb);
880 	unsigned int		flags;
881 	int			ret;
882 
883 	/*
884 	 * The filesystem is now frozen far enough that memory reclaim
885 	 * cannot safely operate on the filesystem. Hence we need to
886 	 * set a GFP_NOFS context here to avoid recursion deadlocks.
887 	 */
888 	flags = memalloc_nofs_save();
889 	xfs_blockgc_stop(mp);
890 	xfs_save_resvblks(mp);
891 	ret = xfs_log_quiesce(mp);
892 	memalloc_nofs_restore(flags);
893 	return ret;
894 }
895 
896 STATIC int
897 xfs_fs_unfreeze(
898 	struct super_block	*sb)
899 {
900 	struct xfs_mount	*mp = XFS_M(sb);
901 
902 	xfs_restore_resvblks(mp);
903 	xfs_log_work_queue(mp);
904 	xfs_blockgc_start(mp);
905 	return 0;
906 }
907 
908 /*
909  * This function fills in xfs_mount_t fields based on mount args.
910  * Note: the superblock _has_ now been read in.
911  */
912 STATIC int
913 xfs_finish_flags(
914 	struct xfs_mount	*mp)
915 {
916 	int			ronly = (mp->m_flags & XFS_MOUNT_RDONLY);
917 
918 	/* Fail a mount where the logbuf is smaller than the log stripe */
919 	if (xfs_sb_version_haslogv2(&mp->m_sb)) {
920 		if (mp->m_logbsize <= 0 &&
921 		    mp->m_sb.sb_logsunit > XLOG_BIG_RECORD_BSIZE) {
922 			mp->m_logbsize = mp->m_sb.sb_logsunit;
923 		} else if (mp->m_logbsize > 0 &&
924 			   mp->m_logbsize < mp->m_sb.sb_logsunit) {
925 			xfs_warn(mp,
926 		"logbuf size must be greater than or equal to log stripe size");
927 			return -EINVAL;
928 		}
929 	} else {
930 		/* Fail a mount if the logbuf is larger than 32K */
931 		if (mp->m_logbsize > XLOG_BIG_RECORD_BSIZE) {
932 			xfs_warn(mp,
933 		"logbuf size for version 1 logs must be 16K or 32K");
934 			return -EINVAL;
935 		}
936 	}
937 
938 	/*
939 	 * V5 filesystems always use attr2 format for attributes.
940 	 */
941 	if (xfs_sb_version_hascrc(&mp->m_sb) &&
942 	    (mp->m_flags & XFS_MOUNT_NOATTR2)) {
943 		xfs_warn(mp, "Cannot mount a V5 filesystem as noattr2. "
944 			     "attr2 is always enabled for V5 filesystems.");
945 		return -EINVAL;
946 	}
947 
948 	/*
949 	 * mkfs'ed attr2 will turn on attr2 mount unless explicitly
950 	 * told by noattr2 to turn it off
951 	 */
952 	if (xfs_sb_version_hasattr2(&mp->m_sb) &&
953 	    !(mp->m_flags & XFS_MOUNT_NOATTR2))
954 		mp->m_flags |= XFS_MOUNT_ATTR2;
955 
956 	/*
957 	 * prohibit r/w mounts of read-only filesystems
958 	 */
959 	if ((mp->m_sb.sb_flags & XFS_SBF_READONLY) && !ronly) {
960 		xfs_warn(mp,
961 			"cannot mount a read-only filesystem as read-write");
962 		return -EROFS;
963 	}
964 
965 	if ((mp->m_qflags & (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE)) &&
966 	    (mp->m_qflags & (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE)) &&
967 	    !xfs_sb_version_has_pquotino(&mp->m_sb)) {
968 		xfs_warn(mp,
969 		  "Super block does not support project and group quota together");
970 		return -EINVAL;
971 	}
972 
973 	return 0;
974 }
975 
976 static int
977 xfs_init_percpu_counters(
978 	struct xfs_mount	*mp)
979 {
980 	int		error;
981 
982 	error = percpu_counter_init(&mp->m_icount, 0, GFP_KERNEL);
983 	if (error)
984 		return -ENOMEM;
985 
986 	error = percpu_counter_init(&mp->m_ifree, 0, GFP_KERNEL);
987 	if (error)
988 		goto free_icount;
989 
990 	error = percpu_counter_init(&mp->m_fdblocks, 0, GFP_KERNEL);
991 	if (error)
992 		goto free_ifree;
993 
994 	error = percpu_counter_init(&mp->m_delalloc_blks, 0, GFP_KERNEL);
995 	if (error)
996 		goto free_fdblocks;
997 
998 	return 0;
999 
1000 free_fdblocks:
1001 	percpu_counter_destroy(&mp->m_fdblocks);
1002 free_ifree:
1003 	percpu_counter_destroy(&mp->m_ifree);
1004 free_icount:
1005 	percpu_counter_destroy(&mp->m_icount);
1006 	return -ENOMEM;
1007 }
1008 
1009 void
1010 xfs_reinit_percpu_counters(
1011 	struct xfs_mount	*mp)
1012 {
1013 	percpu_counter_set(&mp->m_icount, mp->m_sb.sb_icount);
1014 	percpu_counter_set(&mp->m_ifree, mp->m_sb.sb_ifree);
1015 	percpu_counter_set(&mp->m_fdblocks, mp->m_sb.sb_fdblocks);
1016 }
1017 
1018 static void
1019 xfs_destroy_percpu_counters(
1020 	struct xfs_mount	*mp)
1021 {
1022 	percpu_counter_destroy(&mp->m_icount);
1023 	percpu_counter_destroy(&mp->m_ifree);
1024 	percpu_counter_destroy(&mp->m_fdblocks);
1025 	ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
1026 	       percpu_counter_sum(&mp->m_delalloc_blks) == 0);
1027 	percpu_counter_destroy(&mp->m_delalloc_blks);
1028 }
1029 
1030 static void
1031 xfs_fs_put_super(
1032 	struct super_block	*sb)
1033 {
1034 	struct xfs_mount	*mp = XFS_M(sb);
1035 
1036 	/* if ->fill_super failed, we have no mount to tear down */
1037 	if (!sb->s_fs_info)
1038 		return;
1039 
1040 	xfs_notice(mp, "Unmounting Filesystem");
1041 	xfs_filestream_unmount(mp);
1042 	xfs_unmountfs(mp);
1043 
1044 	xfs_freesb(mp);
1045 	free_percpu(mp->m_stats.xs_stats);
1046 	xfs_destroy_percpu_counters(mp);
1047 	xfs_destroy_mount_workqueues(mp);
1048 	xfs_close_devices(mp);
1049 
1050 	sb->s_fs_info = NULL;
1051 	xfs_mount_free(mp);
1052 }
1053 
1054 static long
1055 xfs_fs_nr_cached_objects(
1056 	struct super_block	*sb,
1057 	struct shrink_control	*sc)
1058 {
1059 	/* Paranoia: catch incorrect calls during mount setup or teardown */
1060 	if (WARN_ON_ONCE(!sb->s_fs_info))
1061 		return 0;
1062 	return xfs_reclaim_inodes_count(XFS_M(sb));
1063 }
1064 
1065 static long
1066 xfs_fs_free_cached_objects(
1067 	struct super_block	*sb,
1068 	struct shrink_control	*sc)
1069 {
1070 	return xfs_reclaim_inodes_nr(XFS_M(sb), sc->nr_to_scan);
1071 }
1072 
1073 static const struct super_operations xfs_super_operations = {
1074 	.alloc_inode		= xfs_fs_alloc_inode,
1075 	.destroy_inode		= xfs_fs_destroy_inode,
1076 	.dirty_inode		= xfs_fs_dirty_inode,
1077 	.drop_inode		= xfs_fs_drop_inode,
1078 	.put_super		= xfs_fs_put_super,
1079 	.sync_fs		= xfs_fs_sync_fs,
1080 	.freeze_fs		= xfs_fs_freeze,
1081 	.unfreeze_fs		= xfs_fs_unfreeze,
1082 	.statfs			= xfs_fs_statfs,
1083 	.show_options		= xfs_fs_show_options,
1084 	.nr_cached_objects	= xfs_fs_nr_cached_objects,
1085 	.free_cached_objects	= xfs_fs_free_cached_objects,
1086 };
1087 
1088 static int
1089 suffix_kstrtoint(
1090 	const char	*s,
1091 	unsigned int	base,
1092 	int		*res)
1093 {
1094 	int		last, shift_left_factor = 0, _res;
1095 	char		*value;
1096 	int		ret = 0;
1097 
1098 	value = kstrdup(s, GFP_KERNEL);
1099 	if (!value)
1100 		return -ENOMEM;
1101 
1102 	last = strlen(value) - 1;
1103 	if (value[last] == 'K' || value[last] == 'k') {
1104 		shift_left_factor = 10;
1105 		value[last] = '\0';
1106 	}
1107 	if (value[last] == 'M' || value[last] == 'm') {
1108 		shift_left_factor = 20;
1109 		value[last] = '\0';
1110 	}
1111 	if (value[last] == 'G' || value[last] == 'g') {
1112 		shift_left_factor = 30;
1113 		value[last] = '\0';
1114 	}
1115 
1116 	if (kstrtoint(value, base, &_res))
1117 		ret = -EINVAL;
1118 	kfree(value);
1119 	*res = _res << shift_left_factor;
1120 	return ret;
1121 }
1122 
1123 static inline void
1124 xfs_fs_warn_deprecated(
1125 	struct fs_context	*fc,
1126 	struct fs_parameter	*param,
1127 	uint64_t		flag,
1128 	bool			value)
1129 {
1130 	/* Don't print the warning if reconfiguring and current mount point
1131 	 * already had the flag set
1132 	 */
1133 	if ((fc->purpose & FS_CONTEXT_FOR_RECONFIGURE) &&
1134 			!!(XFS_M(fc->root->d_sb)->m_flags & flag) == value)
1135 		return;
1136 	xfs_warn(fc->s_fs_info, "%s mount option is deprecated.", param->key);
1137 }
1138 
1139 /*
1140  * Set mount state from a mount option.
1141  *
1142  * NOTE: mp->m_super is NULL here!
1143  */
1144 static int
1145 xfs_fs_parse_param(
1146 	struct fs_context	*fc,
1147 	struct fs_parameter	*param)
1148 {
1149 	struct xfs_mount	*parsing_mp = fc->s_fs_info;
1150 	struct fs_parse_result	result;
1151 	int			size = 0;
1152 	int			opt;
1153 
1154 	opt = fs_parse(fc, xfs_fs_parameters, param, &result);
1155 	if (opt < 0)
1156 		return opt;
1157 
1158 	switch (opt) {
1159 	case Opt_logbufs:
1160 		parsing_mp->m_logbufs = result.uint_32;
1161 		return 0;
1162 	case Opt_logbsize:
1163 		if (suffix_kstrtoint(param->string, 10, &parsing_mp->m_logbsize))
1164 			return -EINVAL;
1165 		return 0;
1166 	case Opt_logdev:
1167 		kfree(parsing_mp->m_logname);
1168 		parsing_mp->m_logname = kstrdup(param->string, GFP_KERNEL);
1169 		if (!parsing_mp->m_logname)
1170 			return -ENOMEM;
1171 		return 0;
1172 	case Opt_rtdev:
1173 		kfree(parsing_mp->m_rtname);
1174 		parsing_mp->m_rtname = kstrdup(param->string, GFP_KERNEL);
1175 		if (!parsing_mp->m_rtname)
1176 			return -ENOMEM;
1177 		return 0;
1178 	case Opt_allocsize:
1179 		if (suffix_kstrtoint(param->string, 10, &size))
1180 			return -EINVAL;
1181 		parsing_mp->m_allocsize_log = ffs(size) - 1;
1182 		parsing_mp->m_flags |= XFS_MOUNT_ALLOCSIZE;
1183 		return 0;
1184 	case Opt_grpid:
1185 	case Opt_bsdgroups:
1186 		parsing_mp->m_flags |= XFS_MOUNT_GRPID;
1187 		return 0;
1188 	case Opt_nogrpid:
1189 	case Opt_sysvgroups:
1190 		parsing_mp->m_flags &= ~XFS_MOUNT_GRPID;
1191 		return 0;
1192 	case Opt_wsync:
1193 		parsing_mp->m_flags |= XFS_MOUNT_WSYNC;
1194 		return 0;
1195 	case Opt_norecovery:
1196 		parsing_mp->m_flags |= XFS_MOUNT_NORECOVERY;
1197 		return 0;
1198 	case Opt_noalign:
1199 		parsing_mp->m_flags |= XFS_MOUNT_NOALIGN;
1200 		return 0;
1201 	case Opt_swalloc:
1202 		parsing_mp->m_flags |= XFS_MOUNT_SWALLOC;
1203 		return 0;
1204 	case Opt_sunit:
1205 		parsing_mp->m_dalign = result.uint_32;
1206 		return 0;
1207 	case Opt_swidth:
1208 		parsing_mp->m_swidth = result.uint_32;
1209 		return 0;
1210 	case Opt_inode32:
1211 		parsing_mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1212 		return 0;
1213 	case Opt_inode64:
1214 		parsing_mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1215 		return 0;
1216 	case Opt_nouuid:
1217 		parsing_mp->m_flags |= XFS_MOUNT_NOUUID;
1218 		return 0;
1219 	case Opt_largeio:
1220 		parsing_mp->m_flags |= XFS_MOUNT_LARGEIO;
1221 		return 0;
1222 	case Opt_nolargeio:
1223 		parsing_mp->m_flags &= ~XFS_MOUNT_LARGEIO;
1224 		return 0;
1225 	case Opt_filestreams:
1226 		parsing_mp->m_flags |= XFS_MOUNT_FILESTREAMS;
1227 		return 0;
1228 	case Opt_noquota:
1229 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACCT;
1230 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ENFD;
1231 		parsing_mp->m_qflags &= ~XFS_ALL_QUOTA_ACTIVE;
1232 		return 0;
1233 	case Opt_quota:
1234 	case Opt_uquota:
1235 	case Opt_usrquota:
1236 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE |
1237 				 XFS_UQUOTA_ENFD);
1238 		return 0;
1239 	case Opt_qnoenforce:
1240 	case Opt_uqnoenforce:
1241 		parsing_mp->m_qflags |= (XFS_UQUOTA_ACCT | XFS_UQUOTA_ACTIVE);
1242 		parsing_mp->m_qflags &= ~XFS_UQUOTA_ENFD;
1243 		return 0;
1244 	case Opt_pquota:
1245 	case Opt_prjquota:
1246 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE |
1247 				 XFS_PQUOTA_ENFD);
1248 		return 0;
1249 	case Opt_pqnoenforce:
1250 		parsing_mp->m_qflags |= (XFS_PQUOTA_ACCT | XFS_PQUOTA_ACTIVE);
1251 		parsing_mp->m_qflags &= ~XFS_PQUOTA_ENFD;
1252 		return 0;
1253 	case Opt_gquota:
1254 	case Opt_grpquota:
1255 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE |
1256 				 XFS_GQUOTA_ENFD);
1257 		return 0;
1258 	case Opt_gqnoenforce:
1259 		parsing_mp->m_qflags |= (XFS_GQUOTA_ACCT | XFS_GQUOTA_ACTIVE);
1260 		parsing_mp->m_qflags &= ~XFS_GQUOTA_ENFD;
1261 		return 0;
1262 	case Opt_discard:
1263 		parsing_mp->m_flags |= XFS_MOUNT_DISCARD;
1264 		return 0;
1265 	case Opt_nodiscard:
1266 		parsing_mp->m_flags &= ~XFS_MOUNT_DISCARD;
1267 		return 0;
1268 #ifdef CONFIG_FS_DAX
1269 	case Opt_dax:
1270 		xfs_mount_set_dax_mode(parsing_mp, XFS_DAX_ALWAYS);
1271 		return 0;
1272 	case Opt_dax_enum:
1273 		xfs_mount_set_dax_mode(parsing_mp, result.uint_32);
1274 		return 0;
1275 #endif
1276 	/* Following mount options will be removed in September 2025 */
1277 	case Opt_ikeep:
1278 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_IKEEP, true);
1279 		parsing_mp->m_flags |= XFS_MOUNT_IKEEP;
1280 		return 0;
1281 	case Opt_noikeep:
1282 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_IKEEP, false);
1283 		parsing_mp->m_flags &= ~XFS_MOUNT_IKEEP;
1284 		return 0;
1285 	case Opt_attr2:
1286 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_ATTR2, true);
1287 		parsing_mp->m_flags |= XFS_MOUNT_ATTR2;
1288 		return 0;
1289 	case Opt_noattr2:
1290 		xfs_fs_warn_deprecated(fc, param, XFS_MOUNT_NOATTR2, true);
1291 		parsing_mp->m_flags &= ~XFS_MOUNT_ATTR2;
1292 		parsing_mp->m_flags |= XFS_MOUNT_NOATTR2;
1293 		return 0;
1294 	default:
1295 		xfs_warn(parsing_mp, "unknown mount option [%s].", param->key);
1296 		return -EINVAL;
1297 	}
1298 
1299 	return 0;
1300 }
1301 
1302 static int
1303 xfs_fs_validate_params(
1304 	struct xfs_mount	*mp)
1305 {
1306 	/*
1307 	 * no recovery flag requires a read-only mount
1308 	 */
1309 	if ((mp->m_flags & XFS_MOUNT_NORECOVERY) &&
1310 	    !(mp->m_flags & XFS_MOUNT_RDONLY)) {
1311 		xfs_warn(mp, "no-recovery mounts must be read-only.");
1312 		return -EINVAL;
1313 	}
1314 
1315 	if ((mp->m_flags & XFS_MOUNT_NOALIGN) &&
1316 	    (mp->m_dalign || mp->m_swidth)) {
1317 		xfs_warn(mp,
1318 	"sunit and swidth options incompatible with the noalign option");
1319 		return -EINVAL;
1320 	}
1321 
1322 	if (!IS_ENABLED(CONFIG_XFS_QUOTA) && mp->m_qflags != 0) {
1323 		xfs_warn(mp, "quota support not available in this kernel.");
1324 		return -EINVAL;
1325 	}
1326 
1327 	if ((mp->m_dalign && !mp->m_swidth) ||
1328 	    (!mp->m_dalign && mp->m_swidth)) {
1329 		xfs_warn(mp, "sunit and swidth must be specified together");
1330 		return -EINVAL;
1331 	}
1332 
1333 	if (mp->m_dalign && (mp->m_swidth % mp->m_dalign != 0)) {
1334 		xfs_warn(mp,
1335 	"stripe width (%d) must be a multiple of the stripe unit (%d)",
1336 			mp->m_swidth, mp->m_dalign);
1337 		return -EINVAL;
1338 	}
1339 
1340 	if (mp->m_logbufs != -1 &&
1341 	    mp->m_logbufs != 0 &&
1342 	    (mp->m_logbufs < XLOG_MIN_ICLOGS ||
1343 	     mp->m_logbufs > XLOG_MAX_ICLOGS)) {
1344 		xfs_warn(mp, "invalid logbufs value: %d [not %d-%d]",
1345 			mp->m_logbufs, XLOG_MIN_ICLOGS, XLOG_MAX_ICLOGS);
1346 		return -EINVAL;
1347 	}
1348 
1349 	if (mp->m_logbsize != -1 &&
1350 	    mp->m_logbsize !=  0 &&
1351 	    (mp->m_logbsize < XLOG_MIN_RECORD_BSIZE ||
1352 	     mp->m_logbsize > XLOG_MAX_RECORD_BSIZE ||
1353 	     !is_power_of_2(mp->m_logbsize))) {
1354 		xfs_warn(mp,
1355 			"invalid logbufsize: %d [not 16k,32k,64k,128k or 256k]",
1356 			mp->m_logbsize);
1357 		return -EINVAL;
1358 	}
1359 
1360 	if ((mp->m_flags & XFS_MOUNT_ALLOCSIZE) &&
1361 	    (mp->m_allocsize_log > XFS_MAX_IO_LOG ||
1362 	     mp->m_allocsize_log < XFS_MIN_IO_LOG)) {
1363 		xfs_warn(mp, "invalid log iosize: %d [not %d-%d]",
1364 			mp->m_allocsize_log, XFS_MIN_IO_LOG, XFS_MAX_IO_LOG);
1365 		return -EINVAL;
1366 	}
1367 
1368 	return 0;
1369 }
1370 
1371 static int
1372 xfs_fs_fill_super(
1373 	struct super_block	*sb,
1374 	struct fs_context	*fc)
1375 {
1376 	struct xfs_mount	*mp = sb->s_fs_info;
1377 	struct inode		*root;
1378 	int			flags = 0, error;
1379 
1380 	mp->m_super = sb;
1381 
1382 	error = xfs_fs_validate_params(mp);
1383 	if (error)
1384 		goto out_free_names;
1385 
1386 	sb_min_blocksize(sb, BBSIZE);
1387 	sb->s_xattr = xfs_xattr_handlers;
1388 	sb->s_export_op = &xfs_export_operations;
1389 #ifdef CONFIG_XFS_QUOTA
1390 	sb->s_qcop = &xfs_quotactl_operations;
1391 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
1392 #endif
1393 	sb->s_op = &xfs_super_operations;
1394 
1395 	/*
1396 	 * Delay mount work if the debug hook is set. This is debug
1397 	 * instrumention to coordinate simulation of xfs mount failures with
1398 	 * VFS superblock operations
1399 	 */
1400 	if (xfs_globals.mount_delay) {
1401 		xfs_notice(mp, "Delaying mount for %d seconds.",
1402 			xfs_globals.mount_delay);
1403 		msleep(xfs_globals.mount_delay * 1000);
1404 	}
1405 
1406 	if (fc->sb_flags & SB_SILENT)
1407 		flags |= XFS_MFSI_QUIET;
1408 
1409 	error = xfs_open_devices(mp);
1410 	if (error)
1411 		goto out_free_names;
1412 
1413 	error = xfs_init_mount_workqueues(mp);
1414 	if (error)
1415 		goto out_close_devices;
1416 
1417 	error = xfs_init_percpu_counters(mp);
1418 	if (error)
1419 		goto out_destroy_workqueues;
1420 
1421 	/* Allocate stats memory before we do operations that might use it */
1422 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
1423 	if (!mp->m_stats.xs_stats) {
1424 		error = -ENOMEM;
1425 		goto out_destroy_counters;
1426 	}
1427 
1428 	error = xfs_readsb(mp, flags);
1429 	if (error)
1430 		goto out_free_stats;
1431 
1432 	error = xfs_finish_flags(mp);
1433 	if (error)
1434 		goto out_free_sb;
1435 
1436 	error = xfs_setup_devices(mp);
1437 	if (error)
1438 		goto out_free_sb;
1439 
1440 	/* V4 support is undergoing deprecation. */
1441 	if (!xfs_sb_version_hascrc(&mp->m_sb)) {
1442 #ifdef CONFIG_XFS_SUPPORT_V4
1443 		xfs_warn_once(mp,
1444 	"Deprecated V4 format (crc=0) will not be supported after September 2030.");
1445 #else
1446 		xfs_warn(mp,
1447 	"Deprecated V4 format (crc=0) not supported by kernel.");
1448 		error = -EINVAL;
1449 		goto out_free_sb;
1450 #endif
1451 	}
1452 
1453 	/* Filesystem claims it needs repair, so refuse the mount. */
1454 	if (xfs_sb_version_needsrepair(&mp->m_sb)) {
1455 		xfs_warn(mp, "Filesystem needs repair.  Please run xfs_repair.");
1456 		error = -EFSCORRUPTED;
1457 		goto out_free_sb;
1458 	}
1459 
1460 	/*
1461 	 * Don't touch the filesystem if a user tool thinks it owns the primary
1462 	 * superblock.  mkfs doesn't clear the flag from secondary supers, so
1463 	 * we don't check them at all.
1464 	 */
1465 	if (mp->m_sb.sb_inprogress) {
1466 		xfs_warn(mp, "Offline file system operation in progress!");
1467 		error = -EFSCORRUPTED;
1468 		goto out_free_sb;
1469 	}
1470 
1471 	/*
1472 	 * Until this is fixed only page-sized or smaller data blocks work.
1473 	 */
1474 	if (mp->m_sb.sb_blocksize > PAGE_SIZE) {
1475 		xfs_warn(mp,
1476 		"File system with blocksize %d bytes. "
1477 		"Only pagesize (%ld) or less will currently work.",
1478 				mp->m_sb.sb_blocksize, PAGE_SIZE);
1479 		error = -ENOSYS;
1480 		goto out_free_sb;
1481 	}
1482 
1483 	/* Ensure this filesystem fits in the page cache limits */
1484 	if (xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_dblocks) ||
1485 	    xfs_sb_validate_fsb_count(&mp->m_sb, mp->m_sb.sb_rblocks)) {
1486 		xfs_warn(mp,
1487 		"file system too large to be mounted on this system.");
1488 		error = -EFBIG;
1489 		goto out_free_sb;
1490 	}
1491 
1492 	/*
1493 	 * XFS block mappings use 54 bits to store the logical block offset.
1494 	 * This should suffice to handle the maximum file size that the VFS
1495 	 * supports (currently 2^63 bytes on 64-bit and ULONG_MAX << PAGE_SHIFT
1496 	 * bytes on 32-bit), but as XFS and VFS have gotten the s_maxbytes
1497 	 * calculation wrong on 32-bit kernels in the past, we'll add a WARN_ON
1498 	 * to check this assertion.
1499 	 *
1500 	 * Avoid integer overflow by comparing the maximum bmbt offset to the
1501 	 * maximum pagecache offset in units of fs blocks.
1502 	 */
1503 	if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) {
1504 		xfs_warn(mp,
1505 "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!",
1506 			 XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE),
1507 			 XFS_MAX_FILEOFF);
1508 		error = -EINVAL;
1509 		goto out_free_sb;
1510 	}
1511 
1512 	error = xfs_filestream_mount(mp);
1513 	if (error)
1514 		goto out_free_sb;
1515 
1516 	/*
1517 	 * we must configure the block size in the superblock before we run the
1518 	 * full mount process as the mount process can lookup and cache inodes.
1519 	 */
1520 	sb->s_magic = XFS_SUPER_MAGIC;
1521 	sb->s_blocksize = mp->m_sb.sb_blocksize;
1522 	sb->s_blocksize_bits = ffs(sb->s_blocksize) - 1;
1523 	sb->s_maxbytes = MAX_LFS_FILESIZE;
1524 	sb->s_max_links = XFS_MAXLINK;
1525 	sb->s_time_gran = 1;
1526 	if (xfs_sb_version_hasbigtime(&mp->m_sb)) {
1527 		sb->s_time_min = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MIN);
1528 		sb->s_time_max = xfs_bigtime_to_unix(XFS_BIGTIME_TIME_MAX);
1529 	} else {
1530 		sb->s_time_min = XFS_LEGACY_TIME_MIN;
1531 		sb->s_time_max = XFS_LEGACY_TIME_MAX;
1532 	}
1533 	trace_xfs_inode_timestamp_range(mp, sb->s_time_min, sb->s_time_max);
1534 	sb->s_iflags |= SB_I_CGROUPWB;
1535 
1536 	set_posix_acl_flag(sb);
1537 
1538 	/* version 5 superblocks support inode version counters. */
1539 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1540 		sb->s_flags |= SB_I_VERSION;
1541 
1542 	if (xfs_sb_version_hasbigtime(&mp->m_sb))
1543 		xfs_warn(mp,
1544  "EXPERIMENTAL big timestamp feature in use. Use at your own risk!");
1545 
1546 	if (mp->m_flags & XFS_MOUNT_DAX_ALWAYS) {
1547 		bool rtdev_is_dax = false, datadev_is_dax;
1548 
1549 		xfs_warn(mp,
1550 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1551 
1552 		datadev_is_dax = bdev_dax_supported(mp->m_ddev_targp->bt_bdev,
1553 			sb->s_blocksize);
1554 		if (mp->m_rtdev_targp)
1555 			rtdev_is_dax = bdev_dax_supported(
1556 				mp->m_rtdev_targp->bt_bdev, sb->s_blocksize);
1557 		if (!rtdev_is_dax && !datadev_is_dax) {
1558 			xfs_alert(mp,
1559 			"DAX unsupported by block device. Turning off DAX.");
1560 			xfs_mount_set_dax_mode(mp, XFS_DAX_NEVER);
1561 		}
1562 		if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1563 			xfs_alert(mp,
1564 		"DAX and reflink cannot be used together!");
1565 			error = -EINVAL;
1566 			goto out_filestream_unmount;
1567 		}
1568 	}
1569 
1570 	if (mp->m_flags & XFS_MOUNT_DISCARD) {
1571 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1572 
1573 		if (!blk_queue_discard(q)) {
1574 			xfs_warn(mp, "mounting with \"discard\" option, but "
1575 					"the device does not support discard");
1576 			mp->m_flags &= ~XFS_MOUNT_DISCARD;
1577 		}
1578 	}
1579 
1580 	if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1581 		if (mp->m_sb.sb_rblocks) {
1582 			xfs_alert(mp,
1583 	"reflink not compatible with realtime device!");
1584 			error = -EINVAL;
1585 			goto out_filestream_unmount;
1586 		}
1587 
1588 		if (xfs_globals.always_cow) {
1589 			xfs_info(mp, "using DEBUG-only always_cow mode.");
1590 			mp->m_always_cow = true;
1591 		}
1592 	}
1593 
1594 	if (xfs_sb_version_hasrmapbt(&mp->m_sb) && mp->m_sb.sb_rblocks) {
1595 		xfs_alert(mp,
1596 	"reverse mapping btree not compatible with realtime device!");
1597 		error = -EINVAL;
1598 		goto out_filestream_unmount;
1599 	}
1600 
1601 	if (xfs_sb_version_hasinobtcounts(&mp->m_sb))
1602 		xfs_warn(mp,
1603  "EXPERIMENTAL inode btree counters feature in use. Use at your own risk!");
1604 
1605 	error = xfs_mountfs(mp);
1606 	if (error)
1607 		goto out_filestream_unmount;
1608 
1609 	root = igrab(VFS_I(mp->m_rootip));
1610 	if (!root) {
1611 		error = -ENOENT;
1612 		goto out_unmount;
1613 	}
1614 	sb->s_root = d_make_root(root);
1615 	if (!sb->s_root) {
1616 		error = -ENOMEM;
1617 		goto out_unmount;
1618 	}
1619 
1620 	return 0;
1621 
1622  out_filestream_unmount:
1623 	xfs_filestream_unmount(mp);
1624  out_free_sb:
1625 	xfs_freesb(mp);
1626  out_free_stats:
1627 	free_percpu(mp->m_stats.xs_stats);
1628  out_destroy_counters:
1629 	xfs_destroy_percpu_counters(mp);
1630  out_destroy_workqueues:
1631 	xfs_destroy_mount_workqueues(mp);
1632  out_close_devices:
1633 	xfs_close_devices(mp);
1634  out_free_names:
1635 	sb->s_fs_info = NULL;
1636 	xfs_mount_free(mp);
1637 	return error;
1638 
1639  out_unmount:
1640 	xfs_filestream_unmount(mp);
1641 	xfs_unmountfs(mp);
1642 	goto out_free_sb;
1643 }
1644 
1645 static int
1646 xfs_fs_get_tree(
1647 	struct fs_context	*fc)
1648 {
1649 	return get_tree_bdev(fc, xfs_fs_fill_super);
1650 }
1651 
1652 static int
1653 xfs_remount_rw(
1654 	struct xfs_mount	*mp)
1655 {
1656 	struct xfs_sb		*sbp = &mp->m_sb;
1657 	int error;
1658 
1659 	if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
1660 		xfs_warn(mp,
1661 			"ro->rw transition prohibited on norecovery mount");
1662 		return -EINVAL;
1663 	}
1664 
1665 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
1666 	    xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
1667 		xfs_warn(mp,
1668 	"ro->rw transition prohibited on unknown (0x%x) ro-compat filesystem",
1669 			(sbp->sb_features_ro_compat &
1670 				XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
1671 		return -EINVAL;
1672 	}
1673 
1674 	mp->m_flags &= ~XFS_MOUNT_RDONLY;
1675 
1676 	/*
1677 	 * If this is the first remount to writeable state we might have some
1678 	 * superblock changes to update.
1679 	 */
1680 	if (mp->m_update_sb) {
1681 		error = xfs_sync_sb(mp, false);
1682 		if (error) {
1683 			xfs_warn(mp, "failed to write sb changes");
1684 			return error;
1685 		}
1686 		mp->m_update_sb = false;
1687 	}
1688 
1689 	/*
1690 	 * Fill out the reserve pool if it is empty. Use the stashed value if
1691 	 * it is non-zero, otherwise go with the default.
1692 	 */
1693 	xfs_restore_resvblks(mp);
1694 	xfs_log_work_queue(mp);
1695 
1696 	/* Recover any CoW blocks that never got remapped. */
1697 	error = xfs_reflink_recover_cow(mp);
1698 	if (error) {
1699 		xfs_err(mp,
1700 			"Error %d recovering leftover CoW allocations.", error);
1701 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1702 		return error;
1703 	}
1704 	xfs_blockgc_start(mp);
1705 
1706 	/* Create the per-AG metadata reservation pool .*/
1707 	error = xfs_fs_reserve_ag_blocks(mp);
1708 	if (error && error != -ENOSPC)
1709 		return error;
1710 
1711 	return 0;
1712 }
1713 
1714 static int
1715 xfs_remount_ro(
1716 	struct xfs_mount	*mp)
1717 {
1718 	int error;
1719 
1720 	/*
1721 	 * Cancel background eofb scanning so it cannot race with the final
1722 	 * log force+buftarg wait and deadlock the remount.
1723 	 */
1724 	xfs_blockgc_stop(mp);
1725 
1726 	/* Get rid of any leftover CoW reservations... */
1727 	error = xfs_blockgc_free_space(mp, NULL);
1728 	if (error) {
1729 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1730 		return error;
1731 	}
1732 
1733 	/* Free the per-AG metadata reservation pool. */
1734 	error = xfs_fs_unreserve_ag_blocks(mp);
1735 	if (error) {
1736 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1737 		return error;
1738 	}
1739 
1740 	/*
1741 	 * Before we sync the metadata, we need to free up the reserve block
1742 	 * pool so that the used block count in the superblock on disk is
1743 	 * correct at the end of the remount. Stash the current* reserve pool
1744 	 * size so that if we get remounted rw, we can return it to the same
1745 	 * size.
1746 	 */
1747 	xfs_save_resvblks(mp);
1748 
1749 	xfs_log_clean(mp);
1750 	mp->m_flags |= XFS_MOUNT_RDONLY;
1751 
1752 	return 0;
1753 }
1754 
1755 /*
1756  * Logically we would return an error here to prevent users from believing
1757  * they might have changed mount options using remount which can't be changed.
1758  *
1759  * But unfortunately mount(8) adds all options from mtab and fstab to the mount
1760  * arguments in some cases so we can't blindly reject options, but have to
1761  * check for each specified option if it actually differs from the currently
1762  * set option and only reject it if that's the case.
1763  *
1764  * Until that is implemented we return success for every remount request, and
1765  * silently ignore all options that we can't actually change.
1766  */
1767 static int
1768 xfs_fs_reconfigure(
1769 	struct fs_context *fc)
1770 {
1771 	struct xfs_mount	*mp = XFS_M(fc->root->d_sb);
1772 	struct xfs_mount        *new_mp = fc->s_fs_info;
1773 	xfs_sb_t		*sbp = &mp->m_sb;
1774 	int			flags = fc->sb_flags;
1775 	int			error;
1776 
1777 	/* version 5 superblocks always support version counters. */
1778 	if (XFS_SB_VERSION_NUM(&mp->m_sb) == XFS_SB_VERSION_5)
1779 		fc->sb_flags |= SB_I_VERSION;
1780 
1781 	error = xfs_fs_validate_params(new_mp);
1782 	if (error)
1783 		return error;
1784 
1785 	sync_filesystem(mp->m_super);
1786 
1787 	/* inode32 -> inode64 */
1788 	if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1789 	    !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1790 		mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS;
1791 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1792 	}
1793 
1794 	/* inode64 -> inode32 */
1795 	if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) &&
1796 	    (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) {
1797 		mp->m_flags |= XFS_MOUNT_SMALL_INUMS;
1798 		mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount);
1799 	}
1800 
1801 	/* ro -> rw */
1802 	if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) {
1803 		error = xfs_remount_rw(mp);
1804 		if (error)
1805 			return error;
1806 	}
1807 
1808 	/* rw -> ro */
1809 	if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) {
1810 		error = xfs_remount_ro(mp);
1811 		if (error)
1812 			return error;
1813 	}
1814 
1815 	return 0;
1816 }
1817 
1818 static void xfs_fs_free(
1819 	struct fs_context	*fc)
1820 {
1821 	struct xfs_mount	*mp = fc->s_fs_info;
1822 
1823 	/*
1824 	 * mp is stored in the fs_context when it is initialized.
1825 	 * mp is transferred to the superblock on a successful mount,
1826 	 * but if an error occurs before the transfer we have to free
1827 	 * it here.
1828 	 */
1829 	if (mp)
1830 		xfs_mount_free(mp);
1831 }
1832 
1833 static const struct fs_context_operations xfs_context_ops = {
1834 	.parse_param = xfs_fs_parse_param,
1835 	.get_tree    = xfs_fs_get_tree,
1836 	.reconfigure = xfs_fs_reconfigure,
1837 	.free        = xfs_fs_free,
1838 };
1839 
1840 static int xfs_init_fs_context(
1841 	struct fs_context	*fc)
1842 {
1843 	struct xfs_mount	*mp;
1844 
1845 	mp = kmem_alloc(sizeof(struct xfs_mount), KM_ZERO);
1846 	if (!mp)
1847 		return -ENOMEM;
1848 
1849 	spin_lock_init(&mp->m_sb_lock);
1850 	spin_lock_init(&mp->m_agirotor_lock);
1851 	INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
1852 	spin_lock_init(&mp->m_perag_lock);
1853 	mutex_init(&mp->m_growlock);
1854 	INIT_WORK(&mp->m_flush_inodes_work, xfs_flush_inodes_worker);
1855 	INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker);
1856 	mp->m_kobj.kobject.kset = xfs_kset;
1857 	/*
1858 	 * We don't create the finobt per-ag space reservation until after log
1859 	 * recovery, so we must set this to true so that an ifree transaction
1860 	 * started during log recovery will not depend on space reservations
1861 	 * for finobt expansion.
1862 	 */
1863 	mp->m_finobt_nores = true;
1864 
1865 	/*
1866 	 * These can be overridden by the mount option parsing.
1867 	 */
1868 	mp->m_logbufs = -1;
1869 	mp->m_logbsize = -1;
1870 	mp->m_allocsize_log = 16; /* 64k */
1871 
1872 	/*
1873 	 * Copy binary VFS mount flags we are interested in.
1874 	 */
1875 	if (fc->sb_flags & SB_RDONLY)
1876 		mp->m_flags |= XFS_MOUNT_RDONLY;
1877 	if (fc->sb_flags & SB_DIRSYNC)
1878 		mp->m_flags |= XFS_MOUNT_DIRSYNC;
1879 	if (fc->sb_flags & SB_SYNCHRONOUS)
1880 		mp->m_flags |= XFS_MOUNT_WSYNC;
1881 
1882 	fc->s_fs_info = mp;
1883 	fc->ops = &xfs_context_ops;
1884 
1885 	return 0;
1886 }
1887 
1888 static struct file_system_type xfs_fs_type = {
1889 	.owner			= THIS_MODULE,
1890 	.name			= "xfs",
1891 	.init_fs_context	= xfs_init_fs_context,
1892 	.parameters		= xfs_fs_parameters,
1893 	.kill_sb		= kill_block_super,
1894 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
1895 };
1896 MODULE_ALIAS_FS("xfs");
1897 
1898 STATIC int __init
1899 xfs_init_zones(void)
1900 {
1901 	xfs_log_ticket_zone = kmem_cache_create("xfs_log_ticket",
1902 						sizeof(struct xlog_ticket),
1903 						0, 0, NULL);
1904 	if (!xfs_log_ticket_zone)
1905 		goto out;
1906 
1907 	xfs_bmap_free_item_zone = kmem_cache_create("xfs_bmap_free_item",
1908 					sizeof(struct xfs_extent_free_item),
1909 					0, 0, NULL);
1910 	if (!xfs_bmap_free_item_zone)
1911 		goto out_destroy_log_ticket_zone;
1912 
1913 	xfs_btree_cur_zone = kmem_cache_create("xfs_btree_cur",
1914 					       sizeof(struct xfs_btree_cur),
1915 					       0, 0, NULL);
1916 	if (!xfs_btree_cur_zone)
1917 		goto out_destroy_bmap_free_item_zone;
1918 
1919 	xfs_da_state_zone = kmem_cache_create("xfs_da_state",
1920 					      sizeof(struct xfs_da_state),
1921 					      0, 0, NULL);
1922 	if (!xfs_da_state_zone)
1923 		goto out_destroy_btree_cur_zone;
1924 
1925 	xfs_ifork_zone = kmem_cache_create("xfs_ifork",
1926 					   sizeof(struct xfs_ifork),
1927 					   0, 0, NULL);
1928 	if (!xfs_ifork_zone)
1929 		goto out_destroy_da_state_zone;
1930 
1931 	xfs_trans_zone = kmem_cache_create("xfs_trans",
1932 					   sizeof(struct xfs_trans),
1933 					   0, 0, NULL);
1934 	if (!xfs_trans_zone)
1935 		goto out_destroy_ifork_zone;
1936 
1937 
1938 	/*
1939 	 * The size of the zone allocated buf log item is the maximum
1940 	 * size possible under XFS.  This wastes a little bit of memory,
1941 	 * but it is much faster.
1942 	 */
1943 	xfs_buf_item_zone = kmem_cache_create("xfs_buf_item",
1944 					      sizeof(struct xfs_buf_log_item),
1945 					      0, 0, NULL);
1946 	if (!xfs_buf_item_zone)
1947 		goto out_destroy_trans_zone;
1948 
1949 	xfs_efd_zone = kmem_cache_create("xfs_efd_item",
1950 					(sizeof(struct xfs_efd_log_item) +
1951 					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
1952 					sizeof(struct xfs_extent)),
1953 					0, 0, NULL);
1954 	if (!xfs_efd_zone)
1955 		goto out_destroy_buf_item_zone;
1956 
1957 	xfs_efi_zone = kmem_cache_create("xfs_efi_item",
1958 					 (sizeof(struct xfs_efi_log_item) +
1959 					 (XFS_EFI_MAX_FAST_EXTENTS - 1) *
1960 					 sizeof(struct xfs_extent)),
1961 					 0, 0, NULL);
1962 	if (!xfs_efi_zone)
1963 		goto out_destroy_efd_zone;
1964 
1965 	xfs_inode_zone = kmem_cache_create("xfs_inode",
1966 					   sizeof(struct xfs_inode), 0,
1967 					   (SLAB_HWCACHE_ALIGN |
1968 					    SLAB_RECLAIM_ACCOUNT |
1969 					    SLAB_MEM_SPREAD | SLAB_ACCOUNT),
1970 					   xfs_fs_inode_init_once);
1971 	if (!xfs_inode_zone)
1972 		goto out_destroy_efi_zone;
1973 
1974 	xfs_ili_zone = kmem_cache_create("xfs_ili",
1975 					 sizeof(struct xfs_inode_log_item), 0,
1976 					 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
1977 					 NULL);
1978 	if (!xfs_ili_zone)
1979 		goto out_destroy_inode_zone;
1980 
1981 	xfs_icreate_zone = kmem_cache_create("xfs_icr",
1982 					     sizeof(struct xfs_icreate_item),
1983 					     0, 0, NULL);
1984 	if (!xfs_icreate_zone)
1985 		goto out_destroy_ili_zone;
1986 
1987 	xfs_rud_zone = kmem_cache_create("xfs_rud_item",
1988 					 sizeof(struct xfs_rud_log_item),
1989 					 0, 0, NULL);
1990 	if (!xfs_rud_zone)
1991 		goto out_destroy_icreate_zone;
1992 
1993 	xfs_rui_zone = kmem_cache_create("xfs_rui_item",
1994 			xfs_rui_log_item_sizeof(XFS_RUI_MAX_FAST_EXTENTS),
1995 			0, 0, NULL);
1996 	if (!xfs_rui_zone)
1997 		goto out_destroy_rud_zone;
1998 
1999 	xfs_cud_zone = kmem_cache_create("xfs_cud_item",
2000 					 sizeof(struct xfs_cud_log_item),
2001 					 0, 0, NULL);
2002 	if (!xfs_cud_zone)
2003 		goto out_destroy_rui_zone;
2004 
2005 	xfs_cui_zone = kmem_cache_create("xfs_cui_item",
2006 			xfs_cui_log_item_sizeof(XFS_CUI_MAX_FAST_EXTENTS),
2007 			0, 0, NULL);
2008 	if (!xfs_cui_zone)
2009 		goto out_destroy_cud_zone;
2010 
2011 	xfs_bud_zone = kmem_cache_create("xfs_bud_item",
2012 					 sizeof(struct xfs_bud_log_item),
2013 					 0, 0, NULL);
2014 	if (!xfs_bud_zone)
2015 		goto out_destroy_cui_zone;
2016 
2017 	xfs_bui_zone = kmem_cache_create("xfs_bui_item",
2018 			xfs_bui_log_item_sizeof(XFS_BUI_MAX_FAST_EXTENTS),
2019 			0, 0, NULL);
2020 	if (!xfs_bui_zone)
2021 		goto out_destroy_bud_zone;
2022 
2023 	return 0;
2024 
2025  out_destroy_bud_zone:
2026 	kmem_cache_destroy(xfs_bud_zone);
2027  out_destroy_cui_zone:
2028 	kmem_cache_destroy(xfs_cui_zone);
2029  out_destroy_cud_zone:
2030 	kmem_cache_destroy(xfs_cud_zone);
2031  out_destroy_rui_zone:
2032 	kmem_cache_destroy(xfs_rui_zone);
2033  out_destroy_rud_zone:
2034 	kmem_cache_destroy(xfs_rud_zone);
2035  out_destroy_icreate_zone:
2036 	kmem_cache_destroy(xfs_icreate_zone);
2037  out_destroy_ili_zone:
2038 	kmem_cache_destroy(xfs_ili_zone);
2039  out_destroy_inode_zone:
2040 	kmem_cache_destroy(xfs_inode_zone);
2041  out_destroy_efi_zone:
2042 	kmem_cache_destroy(xfs_efi_zone);
2043  out_destroy_efd_zone:
2044 	kmem_cache_destroy(xfs_efd_zone);
2045  out_destroy_buf_item_zone:
2046 	kmem_cache_destroy(xfs_buf_item_zone);
2047  out_destroy_trans_zone:
2048 	kmem_cache_destroy(xfs_trans_zone);
2049  out_destroy_ifork_zone:
2050 	kmem_cache_destroy(xfs_ifork_zone);
2051  out_destroy_da_state_zone:
2052 	kmem_cache_destroy(xfs_da_state_zone);
2053  out_destroy_btree_cur_zone:
2054 	kmem_cache_destroy(xfs_btree_cur_zone);
2055  out_destroy_bmap_free_item_zone:
2056 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2057  out_destroy_log_ticket_zone:
2058 	kmem_cache_destroy(xfs_log_ticket_zone);
2059  out:
2060 	return -ENOMEM;
2061 }
2062 
2063 STATIC void
2064 xfs_destroy_zones(void)
2065 {
2066 	/*
2067 	 * Make sure all delayed rcu free are flushed before we
2068 	 * destroy caches.
2069 	 */
2070 	rcu_barrier();
2071 	kmem_cache_destroy(xfs_bui_zone);
2072 	kmem_cache_destroy(xfs_bud_zone);
2073 	kmem_cache_destroy(xfs_cui_zone);
2074 	kmem_cache_destroy(xfs_cud_zone);
2075 	kmem_cache_destroy(xfs_rui_zone);
2076 	kmem_cache_destroy(xfs_rud_zone);
2077 	kmem_cache_destroy(xfs_icreate_zone);
2078 	kmem_cache_destroy(xfs_ili_zone);
2079 	kmem_cache_destroy(xfs_inode_zone);
2080 	kmem_cache_destroy(xfs_efi_zone);
2081 	kmem_cache_destroy(xfs_efd_zone);
2082 	kmem_cache_destroy(xfs_buf_item_zone);
2083 	kmem_cache_destroy(xfs_trans_zone);
2084 	kmem_cache_destroy(xfs_ifork_zone);
2085 	kmem_cache_destroy(xfs_da_state_zone);
2086 	kmem_cache_destroy(xfs_btree_cur_zone);
2087 	kmem_cache_destroy(xfs_bmap_free_item_zone);
2088 	kmem_cache_destroy(xfs_log_ticket_zone);
2089 }
2090 
2091 STATIC int __init
2092 xfs_init_workqueues(void)
2093 {
2094 	/*
2095 	 * The allocation workqueue can be used in memory reclaim situations
2096 	 * (writepage path), and parallelism is only limited by the number of
2097 	 * AGs in all the filesystems mounted. Hence use the default large
2098 	 * max_active value for this workqueue.
2099 	 */
2100 	xfs_alloc_wq = alloc_workqueue("xfsalloc",
2101 			XFS_WQFLAGS(WQ_MEM_RECLAIM | WQ_FREEZABLE), 0);
2102 	if (!xfs_alloc_wq)
2103 		return -ENOMEM;
2104 
2105 	xfs_discard_wq = alloc_workqueue("xfsdiscard", XFS_WQFLAGS(WQ_UNBOUND),
2106 			0);
2107 	if (!xfs_discard_wq)
2108 		goto out_free_alloc_wq;
2109 
2110 	return 0;
2111 out_free_alloc_wq:
2112 	destroy_workqueue(xfs_alloc_wq);
2113 	return -ENOMEM;
2114 }
2115 
2116 STATIC void
2117 xfs_destroy_workqueues(void)
2118 {
2119 	destroy_workqueue(xfs_discard_wq);
2120 	destroy_workqueue(xfs_alloc_wq);
2121 }
2122 
2123 STATIC int __init
2124 init_xfs_fs(void)
2125 {
2126 	int			error;
2127 
2128 	xfs_check_ondisk_structs();
2129 
2130 	printk(KERN_INFO XFS_VERSION_STRING " with "
2131 			 XFS_BUILD_OPTIONS " enabled\n");
2132 
2133 	xfs_dir_startup();
2134 
2135 	error = xfs_init_zones();
2136 	if (error)
2137 		goto out;
2138 
2139 	error = xfs_init_workqueues();
2140 	if (error)
2141 		goto out_destroy_zones;
2142 
2143 	error = xfs_mru_cache_init();
2144 	if (error)
2145 		goto out_destroy_wq;
2146 
2147 	error = xfs_buf_init();
2148 	if (error)
2149 		goto out_mru_cache_uninit;
2150 
2151 	error = xfs_init_procfs();
2152 	if (error)
2153 		goto out_buf_terminate;
2154 
2155 	error = xfs_sysctl_register();
2156 	if (error)
2157 		goto out_cleanup_procfs;
2158 
2159 	xfs_kset = kset_create_and_add("xfs", NULL, fs_kobj);
2160 	if (!xfs_kset) {
2161 		error = -ENOMEM;
2162 		goto out_sysctl_unregister;
2163 	}
2164 
2165 	xfsstats.xs_kobj.kobject.kset = xfs_kset;
2166 
2167 	xfsstats.xs_stats = alloc_percpu(struct xfsstats);
2168 	if (!xfsstats.xs_stats) {
2169 		error = -ENOMEM;
2170 		goto out_kset_unregister;
2171 	}
2172 
2173 	error = xfs_sysfs_init(&xfsstats.xs_kobj, &xfs_stats_ktype, NULL,
2174 			       "stats");
2175 	if (error)
2176 		goto out_free_stats;
2177 
2178 #ifdef DEBUG
2179 	xfs_dbg_kobj.kobject.kset = xfs_kset;
2180 	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
2181 	if (error)
2182 		goto out_remove_stats_kobj;
2183 #endif
2184 
2185 	error = xfs_qm_init();
2186 	if (error)
2187 		goto out_remove_dbg_kobj;
2188 
2189 	error = register_filesystem(&xfs_fs_type);
2190 	if (error)
2191 		goto out_qm_exit;
2192 	return 0;
2193 
2194  out_qm_exit:
2195 	xfs_qm_exit();
2196  out_remove_dbg_kobj:
2197 #ifdef DEBUG
2198 	xfs_sysfs_del(&xfs_dbg_kobj);
2199  out_remove_stats_kobj:
2200 #endif
2201 	xfs_sysfs_del(&xfsstats.xs_kobj);
2202  out_free_stats:
2203 	free_percpu(xfsstats.xs_stats);
2204  out_kset_unregister:
2205 	kset_unregister(xfs_kset);
2206  out_sysctl_unregister:
2207 	xfs_sysctl_unregister();
2208  out_cleanup_procfs:
2209 	xfs_cleanup_procfs();
2210  out_buf_terminate:
2211 	xfs_buf_terminate();
2212  out_mru_cache_uninit:
2213 	xfs_mru_cache_uninit();
2214  out_destroy_wq:
2215 	xfs_destroy_workqueues();
2216  out_destroy_zones:
2217 	xfs_destroy_zones();
2218  out:
2219 	return error;
2220 }
2221 
2222 STATIC void __exit
2223 exit_xfs_fs(void)
2224 {
2225 	xfs_qm_exit();
2226 	unregister_filesystem(&xfs_fs_type);
2227 #ifdef DEBUG
2228 	xfs_sysfs_del(&xfs_dbg_kobj);
2229 #endif
2230 	xfs_sysfs_del(&xfsstats.xs_kobj);
2231 	free_percpu(xfsstats.xs_stats);
2232 	kset_unregister(xfs_kset);
2233 	xfs_sysctl_unregister();
2234 	xfs_cleanup_procfs();
2235 	xfs_buf_terminate();
2236 	xfs_mru_cache_uninit();
2237 	xfs_destroy_workqueues();
2238 	xfs_destroy_zones();
2239 	xfs_uuid_table_free();
2240 }
2241 
2242 module_init(init_xfs_fs);
2243 module_exit(exit_xfs_fs);
2244 
2245 MODULE_AUTHOR("Silicon Graphics, Inc.");
2246 MODULE_DESCRIPTION(XFS_VERSION_STRING " with " XFS_BUILD_OPTIONS " enabled");
2247 MODULE_LICENSE("GPL");
2248