xref: /openbmc/linux/fs/xfs/xfs_inode_item.c (revision 0d456bad)
1 /*
2  * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_log.h"
22 #include "xfs_trans.h"
23 #include "xfs_sb.h"
24 #include "xfs_ag.h"
25 #include "xfs_mount.h"
26 #include "xfs_trans_priv.h"
27 #include "xfs_bmap_btree.h"
28 #include "xfs_dinode.h"
29 #include "xfs_inode.h"
30 #include "xfs_inode_item.h"
31 #include "xfs_error.h"
32 #include "xfs_trace.h"
33 
34 
35 kmem_zone_t	*xfs_ili_zone;		/* inode log item zone */
36 
37 static inline struct xfs_inode_log_item *INODE_ITEM(struct xfs_log_item *lip)
38 {
39 	return container_of(lip, struct xfs_inode_log_item, ili_item);
40 }
41 
42 
43 /*
44  * This returns the number of iovecs needed to log the given inode item.
45  *
46  * We need one iovec for the inode log format structure, one for the
47  * inode core, and possibly one for the inode data/extents/b-tree root
48  * and one for the inode attribute data/extents/b-tree root.
49  */
50 STATIC uint
51 xfs_inode_item_size(
52 	struct xfs_log_item	*lip)
53 {
54 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
55 	struct xfs_inode	*ip = iip->ili_inode;
56 	uint			nvecs = 2;
57 
58 	switch (ip->i_d.di_format) {
59 	case XFS_DINODE_FMT_EXTENTS:
60 		if ((iip->ili_fields & XFS_ILOG_DEXT) &&
61 		    ip->i_d.di_nextents > 0 &&
62 		    ip->i_df.if_bytes > 0)
63 			nvecs++;
64 		break;
65 
66 	case XFS_DINODE_FMT_BTREE:
67 		if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
68 		    ip->i_df.if_broot_bytes > 0)
69 			nvecs++;
70 		break;
71 
72 	case XFS_DINODE_FMT_LOCAL:
73 		if ((iip->ili_fields & XFS_ILOG_DDATA) &&
74 		    ip->i_df.if_bytes > 0)
75 			nvecs++;
76 		break;
77 
78 	case XFS_DINODE_FMT_DEV:
79 	case XFS_DINODE_FMT_UUID:
80 		break;
81 
82 	default:
83 		ASSERT(0);
84 		break;
85 	}
86 
87 	if (!XFS_IFORK_Q(ip))
88 		return nvecs;
89 
90 
91 	/*
92 	 * Log any necessary attribute data.
93 	 */
94 	switch (ip->i_d.di_aformat) {
95 	case XFS_DINODE_FMT_EXTENTS:
96 		if ((iip->ili_fields & XFS_ILOG_AEXT) &&
97 		    ip->i_d.di_anextents > 0 &&
98 		    ip->i_afp->if_bytes > 0)
99 			nvecs++;
100 		break;
101 
102 	case XFS_DINODE_FMT_BTREE:
103 		if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
104 		    ip->i_afp->if_broot_bytes > 0)
105 			nvecs++;
106 		break;
107 
108 	case XFS_DINODE_FMT_LOCAL:
109 		if ((iip->ili_fields & XFS_ILOG_ADATA) &&
110 		    ip->i_afp->if_bytes > 0)
111 			nvecs++;
112 		break;
113 
114 	default:
115 		ASSERT(0);
116 		break;
117 	}
118 
119 	return nvecs;
120 }
121 
122 /*
123  * xfs_inode_item_format_extents - convert in-core extents to on-disk form
124  *
125  * For either the data or attr fork in extent format, we need to endian convert
126  * the in-core extent as we place them into the on-disk inode. In this case, we
127  * need to do this conversion before we write the extents into the log. Because
128  * we don't have the disk inode to write into here, we allocate a buffer and
129  * format the extents into it via xfs_iextents_copy(). We free the buffer in
130  * the unlock routine after the copy for the log has been made.
131  *
132  * In the case of the data fork, the in-core and on-disk fork sizes can be
133  * different due to delayed allocation extents. We only log on-disk extents
134  * here, so always use the physical fork size to determine the size of the
135  * buffer we need to allocate.
136  */
137 STATIC void
138 xfs_inode_item_format_extents(
139 	struct xfs_inode	*ip,
140 	struct xfs_log_iovec	*vecp,
141 	int			whichfork,
142 	int			type)
143 {
144 	xfs_bmbt_rec_t		*ext_buffer;
145 
146 	ext_buffer = kmem_alloc(XFS_IFORK_SIZE(ip, whichfork), KM_SLEEP);
147 	if (whichfork == XFS_DATA_FORK)
148 		ip->i_itemp->ili_extents_buf = ext_buffer;
149 	else
150 		ip->i_itemp->ili_aextents_buf = ext_buffer;
151 
152 	vecp->i_addr = ext_buffer;
153 	vecp->i_len = xfs_iextents_copy(ip, ext_buffer, whichfork);
154 	vecp->i_type = type;
155 }
156 
157 /*
158  * This is called to fill in the vector of log iovecs for the
159  * given inode log item.  It fills the first item with an inode
160  * log format structure, the second with the on-disk inode structure,
161  * and a possible third and/or fourth with the inode data/extents/b-tree
162  * root and inode attributes data/extents/b-tree root.
163  */
164 STATIC void
165 xfs_inode_item_format(
166 	struct xfs_log_item	*lip,
167 	struct xfs_log_iovec	*vecp)
168 {
169 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
170 	struct xfs_inode	*ip = iip->ili_inode;
171 	uint			nvecs;
172 	size_t			data_bytes;
173 	xfs_mount_t		*mp;
174 
175 	vecp->i_addr = &iip->ili_format;
176 	vecp->i_len  = sizeof(xfs_inode_log_format_t);
177 	vecp->i_type = XLOG_REG_TYPE_IFORMAT;
178 	vecp++;
179 	nvecs	     = 1;
180 
181 	vecp->i_addr = &ip->i_d;
182 	vecp->i_len  = sizeof(struct xfs_icdinode);
183 	vecp->i_type = XLOG_REG_TYPE_ICORE;
184 	vecp++;
185 	nvecs++;
186 
187 	/*
188 	 * If this is really an old format inode, then we need to
189 	 * log it as such.  This means that we have to copy the link
190 	 * count from the new field to the old.  We don't have to worry
191 	 * about the new fields, because nothing trusts them as long as
192 	 * the old inode version number is there.  If the superblock already
193 	 * has a new version number, then we don't bother converting back.
194 	 */
195 	mp = ip->i_mount;
196 	ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
197 	if (ip->i_d.di_version == 1) {
198 		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
199 			/*
200 			 * Convert it back.
201 			 */
202 			ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
203 			ip->i_d.di_onlink = ip->i_d.di_nlink;
204 		} else {
205 			/*
206 			 * The superblock version has already been bumped,
207 			 * so just make the conversion to the new inode
208 			 * format permanent.
209 			 */
210 			ip->i_d.di_version = 2;
211 			ip->i_d.di_onlink = 0;
212 			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
213 		}
214 	}
215 
216 	switch (ip->i_d.di_format) {
217 	case XFS_DINODE_FMT_EXTENTS:
218 		iip->ili_fields &=
219 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
220 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
221 
222 		if ((iip->ili_fields & XFS_ILOG_DEXT) &&
223 		    ip->i_d.di_nextents > 0 &&
224 		    ip->i_df.if_bytes > 0) {
225 			ASSERT(ip->i_df.if_u1.if_extents != NULL);
226 			ASSERT(ip->i_df.if_bytes / sizeof(xfs_bmbt_rec_t) > 0);
227 			ASSERT(iip->ili_extents_buf == NULL);
228 
229 #ifdef XFS_NATIVE_HOST
230                        if (ip->i_d.di_nextents == ip->i_df.if_bytes /
231                                                (uint)sizeof(xfs_bmbt_rec_t)) {
232 				/*
233 				 * There are no delayed allocation
234 				 * extents, so just point to the
235 				 * real extents array.
236 				 */
237 				vecp->i_addr = ip->i_df.if_u1.if_extents;
238 				vecp->i_len = ip->i_df.if_bytes;
239 				vecp->i_type = XLOG_REG_TYPE_IEXT;
240 			} else
241 #endif
242 			{
243 				xfs_inode_item_format_extents(ip, vecp,
244 					XFS_DATA_FORK, XLOG_REG_TYPE_IEXT);
245 			}
246 			ASSERT(vecp->i_len <= ip->i_df.if_bytes);
247 			iip->ili_format.ilf_dsize = vecp->i_len;
248 			vecp++;
249 			nvecs++;
250 		} else {
251 			iip->ili_fields &= ~XFS_ILOG_DEXT;
252 		}
253 		break;
254 
255 	case XFS_DINODE_FMT_BTREE:
256 		iip->ili_fields &=
257 			~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
258 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
259 
260 		if ((iip->ili_fields & XFS_ILOG_DBROOT) &&
261 		    ip->i_df.if_broot_bytes > 0) {
262 			ASSERT(ip->i_df.if_broot != NULL);
263 			vecp->i_addr = ip->i_df.if_broot;
264 			vecp->i_len = ip->i_df.if_broot_bytes;
265 			vecp->i_type = XLOG_REG_TYPE_IBROOT;
266 			vecp++;
267 			nvecs++;
268 			iip->ili_format.ilf_dsize = ip->i_df.if_broot_bytes;
269 		} else {
270 			ASSERT(!(iip->ili_fields &
271 				 XFS_ILOG_DBROOT));
272 #ifdef XFS_TRANS_DEBUG
273 			if (iip->ili_root_size > 0) {
274 				ASSERT(iip->ili_root_size ==
275 				       ip->i_df.if_broot_bytes);
276 				ASSERT(memcmp(iip->ili_orig_root,
277 					    ip->i_df.if_broot,
278 					    iip->ili_root_size) == 0);
279 			} else {
280 				ASSERT(ip->i_df.if_broot_bytes == 0);
281 			}
282 #endif
283 			iip->ili_fields &= ~XFS_ILOG_DBROOT;
284 		}
285 		break;
286 
287 	case XFS_DINODE_FMT_LOCAL:
288 		iip->ili_fields &=
289 			~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
290 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
291 		if ((iip->ili_fields & XFS_ILOG_DDATA) &&
292 		    ip->i_df.if_bytes > 0) {
293 			ASSERT(ip->i_df.if_u1.if_data != NULL);
294 			ASSERT(ip->i_d.di_size > 0);
295 
296 			vecp->i_addr = ip->i_df.if_u1.if_data;
297 			/*
298 			 * Round i_bytes up to a word boundary.
299 			 * The underlying memory is guaranteed to
300 			 * to be there by xfs_idata_realloc().
301 			 */
302 			data_bytes = roundup(ip->i_df.if_bytes, 4);
303 			ASSERT((ip->i_df.if_real_bytes == 0) ||
304 			       (ip->i_df.if_real_bytes == data_bytes));
305 			vecp->i_len = (int)data_bytes;
306 			vecp->i_type = XLOG_REG_TYPE_ILOCAL;
307 			vecp++;
308 			nvecs++;
309 			iip->ili_format.ilf_dsize = (unsigned)data_bytes;
310 		} else {
311 			iip->ili_fields &= ~XFS_ILOG_DDATA;
312 		}
313 		break;
314 
315 	case XFS_DINODE_FMT_DEV:
316 		iip->ili_fields &=
317 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
318 			  XFS_ILOG_DEXT | XFS_ILOG_UUID);
319 		if (iip->ili_fields & XFS_ILOG_DEV) {
320 			iip->ili_format.ilf_u.ilfu_rdev =
321 				ip->i_df.if_u2.if_rdev;
322 		}
323 		break;
324 
325 	case XFS_DINODE_FMT_UUID:
326 		iip->ili_fields &=
327 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
328 			  XFS_ILOG_DEXT | XFS_ILOG_DEV);
329 		if (iip->ili_fields & XFS_ILOG_UUID) {
330 			iip->ili_format.ilf_u.ilfu_uuid =
331 				ip->i_df.if_u2.if_uuid;
332 		}
333 		break;
334 
335 	default:
336 		ASSERT(0);
337 		break;
338 	}
339 
340 	/*
341 	 * If there are no attributes associated with the file, then we're done.
342 	 */
343 	if (!XFS_IFORK_Q(ip)) {
344 		iip->ili_fields &=
345 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT);
346 		goto out;
347 	}
348 
349 	switch (ip->i_d.di_aformat) {
350 	case XFS_DINODE_FMT_EXTENTS:
351 		iip->ili_fields &=
352 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT);
353 
354 		if ((iip->ili_fields & XFS_ILOG_AEXT) &&
355 		    ip->i_d.di_anextents > 0 &&
356 		    ip->i_afp->if_bytes > 0) {
357 			ASSERT(ip->i_afp->if_bytes / sizeof(xfs_bmbt_rec_t) ==
358 				ip->i_d.di_anextents);
359 			ASSERT(ip->i_afp->if_u1.if_extents != NULL);
360 #ifdef XFS_NATIVE_HOST
361 			/*
362 			 * There are not delayed allocation extents
363 			 * for attributes, so just point at the array.
364 			 */
365 			vecp->i_addr = ip->i_afp->if_u1.if_extents;
366 			vecp->i_len = ip->i_afp->if_bytes;
367 			vecp->i_type = XLOG_REG_TYPE_IATTR_EXT;
368 #else
369 			ASSERT(iip->ili_aextents_buf == NULL);
370 			xfs_inode_item_format_extents(ip, vecp,
371 					XFS_ATTR_FORK, XLOG_REG_TYPE_IATTR_EXT);
372 #endif
373 			iip->ili_format.ilf_asize = vecp->i_len;
374 			vecp++;
375 			nvecs++;
376 		} else {
377 			iip->ili_fields &= ~XFS_ILOG_AEXT;
378 		}
379 		break;
380 
381 	case XFS_DINODE_FMT_BTREE:
382 		iip->ili_fields &=
383 			~(XFS_ILOG_ADATA | XFS_ILOG_AEXT);
384 
385 		if ((iip->ili_fields & XFS_ILOG_ABROOT) &&
386 		    ip->i_afp->if_broot_bytes > 0) {
387 			ASSERT(ip->i_afp->if_broot != NULL);
388 
389 			vecp->i_addr = ip->i_afp->if_broot;
390 			vecp->i_len = ip->i_afp->if_broot_bytes;
391 			vecp->i_type = XLOG_REG_TYPE_IATTR_BROOT;
392 			vecp++;
393 			nvecs++;
394 			iip->ili_format.ilf_asize = ip->i_afp->if_broot_bytes;
395 		} else {
396 			iip->ili_fields &= ~XFS_ILOG_ABROOT;
397 		}
398 		break;
399 
400 	case XFS_DINODE_FMT_LOCAL:
401 		iip->ili_fields &=
402 			~(XFS_ILOG_AEXT | XFS_ILOG_ABROOT);
403 
404 		if ((iip->ili_fields & XFS_ILOG_ADATA) &&
405 		    ip->i_afp->if_bytes > 0) {
406 			ASSERT(ip->i_afp->if_u1.if_data != NULL);
407 
408 			vecp->i_addr = ip->i_afp->if_u1.if_data;
409 			/*
410 			 * Round i_bytes up to a word boundary.
411 			 * The underlying memory is guaranteed to
412 			 * to be there by xfs_idata_realloc().
413 			 */
414 			data_bytes = roundup(ip->i_afp->if_bytes, 4);
415 			ASSERT((ip->i_afp->if_real_bytes == 0) ||
416 			       (ip->i_afp->if_real_bytes == data_bytes));
417 			vecp->i_len = (int)data_bytes;
418 			vecp->i_type = XLOG_REG_TYPE_IATTR_LOCAL;
419 			vecp++;
420 			nvecs++;
421 			iip->ili_format.ilf_asize = (unsigned)data_bytes;
422 		} else {
423 			iip->ili_fields &= ~XFS_ILOG_ADATA;
424 		}
425 		break;
426 
427 	default:
428 		ASSERT(0);
429 		break;
430 	}
431 
432 out:
433 	/*
434 	 * Now update the log format that goes out to disk from the in-core
435 	 * values.  We always write the inode core to make the arithmetic
436 	 * games in recovery easier, which isn't a big deal as just about any
437 	 * transaction would dirty it anyway.
438 	 */
439 	iip->ili_format.ilf_fields = XFS_ILOG_CORE |
440 		(iip->ili_fields & ~XFS_ILOG_TIMESTAMP);
441 	iip->ili_format.ilf_size = nvecs;
442 }
443 
444 
445 /*
446  * This is called to pin the inode associated with the inode log
447  * item in memory so it cannot be written out.
448  */
449 STATIC void
450 xfs_inode_item_pin(
451 	struct xfs_log_item	*lip)
452 {
453 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;
454 
455 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
456 
457 	trace_xfs_inode_pin(ip, _RET_IP_);
458 	atomic_inc(&ip->i_pincount);
459 }
460 
461 
462 /*
463  * This is called to unpin the inode associated with the inode log
464  * item which was previously pinned with a call to xfs_inode_item_pin().
465  *
466  * Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
467  */
468 STATIC void
469 xfs_inode_item_unpin(
470 	struct xfs_log_item	*lip,
471 	int			remove)
472 {
473 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;
474 
475 	trace_xfs_inode_unpin(ip, _RET_IP_);
476 	ASSERT(atomic_read(&ip->i_pincount) > 0);
477 	if (atomic_dec_and_test(&ip->i_pincount))
478 		wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
479 }
480 
481 STATIC uint
482 xfs_inode_item_push(
483 	struct xfs_log_item	*lip,
484 	struct list_head	*buffer_list)
485 {
486 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
487 	struct xfs_inode	*ip = iip->ili_inode;
488 	struct xfs_buf		*bp = NULL;
489 	uint			rval = XFS_ITEM_SUCCESS;
490 	int			error;
491 
492 	if (xfs_ipincount(ip) > 0)
493 		return XFS_ITEM_PINNED;
494 
495 	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
496 		return XFS_ITEM_LOCKED;
497 
498 	/*
499 	 * Re-check the pincount now that we stabilized the value by
500 	 * taking the ilock.
501 	 */
502 	if (xfs_ipincount(ip) > 0) {
503 		rval = XFS_ITEM_PINNED;
504 		goto out_unlock;
505 	}
506 
507 	/*
508 	 * Stale inode items should force out the iclog.
509 	 */
510 	if (ip->i_flags & XFS_ISTALE) {
511 		rval = XFS_ITEM_PINNED;
512 		goto out_unlock;
513 	}
514 
515 	/*
516 	 * Someone else is already flushing the inode.  Nothing we can do
517 	 * here but wait for the flush to finish and remove the item from
518 	 * the AIL.
519 	 */
520 	if (!xfs_iflock_nowait(ip)) {
521 		rval = XFS_ITEM_FLUSHING;
522 		goto out_unlock;
523 	}
524 
525 	ASSERT(iip->ili_fields != 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));
526 	ASSERT(iip->ili_logged == 0 || XFS_FORCED_SHUTDOWN(ip->i_mount));
527 
528 	spin_unlock(&lip->li_ailp->xa_lock);
529 
530 	error = xfs_iflush(ip, &bp);
531 	if (!error) {
532 		if (!xfs_buf_delwri_queue(bp, buffer_list))
533 			rval = XFS_ITEM_FLUSHING;
534 		xfs_buf_relse(bp);
535 	}
536 
537 	spin_lock(&lip->li_ailp->xa_lock);
538 out_unlock:
539 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
540 	return rval;
541 }
542 
543 /*
544  * Unlock the inode associated with the inode log item.
545  * Clear the fields of the inode and inode log item that
546  * are specific to the current transaction.  If the
547  * hold flags is set, do not unlock the inode.
548  */
549 STATIC void
550 xfs_inode_item_unlock(
551 	struct xfs_log_item	*lip)
552 {
553 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
554 	struct xfs_inode	*ip = iip->ili_inode;
555 	unsigned short		lock_flags;
556 
557 	ASSERT(ip->i_itemp != NULL);
558 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
559 
560 	/*
561 	 * If the inode needed a separate buffer with which to log
562 	 * its extents, then free it now.
563 	 */
564 	if (iip->ili_extents_buf != NULL) {
565 		ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS);
566 		ASSERT(ip->i_d.di_nextents > 0);
567 		ASSERT(iip->ili_fields & XFS_ILOG_DEXT);
568 		ASSERT(ip->i_df.if_bytes > 0);
569 		kmem_free(iip->ili_extents_buf);
570 		iip->ili_extents_buf = NULL;
571 	}
572 	if (iip->ili_aextents_buf != NULL) {
573 		ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS);
574 		ASSERT(ip->i_d.di_anextents > 0);
575 		ASSERT(iip->ili_fields & XFS_ILOG_AEXT);
576 		ASSERT(ip->i_afp->if_bytes > 0);
577 		kmem_free(iip->ili_aextents_buf);
578 		iip->ili_aextents_buf = NULL;
579 	}
580 
581 	lock_flags = iip->ili_lock_flags;
582 	iip->ili_lock_flags = 0;
583 	if (lock_flags)
584 		xfs_iunlock(ip, lock_flags);
585 }
586 
587 /*
588  * This is called to find out where the oldest active copy of the inode log
589  * item in the on disk log resides now that the last log write of it completed
590  * at the given lsn.  Since we always re-log all dirty data in an inode, the
591  * latest copy in the on disk log is the only one that matters.  Therefore,
592  * simply return the given lsn.
593  *
594  * If the inode has been marked stale because the cluster is being freed, we
595  * don't want to (re-)insert this inode into the AIL. There is a race condition
596  * where the cluster buffer may be unpinned before the inode is inserted into
597  * the AIL during transaction committed processing. If the buffer is unpinned
598  * before the inode item has been committed and inserted, then it is possible
599  * for the buffer to be written and IO completes before the inode is inserted
600  * into the AIL. In that case, we'd be inserting a clean, stale inode into the
601  * AIL which will never get removed. It will, however, get reclaimed which
602  * triggers an assert in xfs_inode_free() complaining about freein an inode
603  * still in the AIL.
604  *
605  * To avoid this, just unpin the inode directly and return a LSN of -1 so the
606  * transaction committed code knows that it does not need to do any further
607  * processing on the item.
608  */
609 STATIC xfs_lsn_t
610 xfs_inode_item_committed(
611 	struct xfs_log_item	*lip,
612 	xfs_lsn_t		lsn)
613 {
614 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
615 	struct xfs_inode	*ip = iip->ili_inode;
616 
617 	if (xfs_iflags_test(ip, XFS_ISTALE)) {
618 		xfs_inode_item_unpin(lip, 0);
619 		return -1;
620 	}
621 	return lsn;
622 }
623 
624 /*
625  * XXX rcc - this one really has to do something.  Probably needs
626  * to stamp in a new field in the incore inode.
627  */
628 STATIC void
629 xfs_inode_item_committing(
630 	struct xfs_log_item	*lip,
631 	xfs_lsn_t		lsn)
632 {
633 	INODE_ITEM(lip)->ili_last_lsn = lsn;
634 }
635 
636 /*
637  * This is the ops vector shared by all buf log items.
638  */
639 static const struct xfs_item_ops xfs_inode_item_ops = {
640 	.iop_size	= xfs_inode_item_size,
641 	.iop_format	= xfs_inode_item_format,
642 	.iop_pin	= xfs_inode_item_pin,
643 	.iop_unpin	= xfs_inode_item_unpin,
644 	.iop_unlock	= xfs_inode_item_unlock,
645 	.iop_committed	= xfs_inode_item_committed,
646 	.iop_push	= xfs_inode_item_push,
647 	.iop_committing = xfs_inode_item_committing
648 };
649 
650 
651 /*
652  * Initialize the inode log item for a newly allocated (in-core) inode.
653  */
654 void
655 xfs_inode_item_init(
656 	struct xfs_inode	*ip,
657 	struct xfs_mount	*mp)
658 {
659 	struct xfs_inode_log_item *iip;
660 
661 	ASSERT(ip->i_itemp == NULL);
662 	iip = ip->i_itemp = kmem_zone_zalloc(xfs_ili_zone, KM_SLEEP);
663 
664 	iip->ili_inode = ip;
665 	xfs_log_item_init(mp, &iip->ili_item, XFS_LI_INODE,
666 						&xfs_inode_item_ops);
667 	iip->ili_format.ilf_type = XFS_LI_INODE;
668 	iip->ili_format.ilf_ino = ip->i_ino;
669 	iip->ili_format.ilf_blkno = ip->i_imap.im_blkno;
670 	iip->ili_format.ilf_len = ip->i_imap.im_len;
671 	iip->ili_format.ilf_boffset = ip->i_imap.im_boffset;
672 }
673 
674 /*
675  * Free the inode log item and any memory hanging off of it.
676  */
677 void
678 xfs_inode_item_destroy(
679 	xfs_inode_t	*ip)
680 {
681 #ifdef XFS_TRANS_DEBUG
682 	if (ip->i_itemp->ili_root_size != 0) {
683 		kmem_free(ip->i_itemp->ili_orig_root);
684 	}
685 #endif
686 	kmem_zone_free(xfs_ili_zone, ip->i_itemp);
687 }
688 
689 
690 /*
691  * This is the inode flushing I/O completion routine.  It is called
692  * from interrupt level when the buffer containing the inode is
693  * flushed to disk.  It is responsible for removing the inode item
694  * from the AIL if it has not been re-logged, and unlocking the inode's
695  * flush lock.
696  *
697  * To reduce AIL lock traffic as much as possible, we scan the buffer log item
698  * list for other inodes that will run this function. We remove them from the
699  * buffer list so we can process all the inode IO completions in one AIL lock
700  * traversal.
701  */
702 void
703 xfs_iflush_done(
704 	struct xfs_buf		*bp,
705 	struct xfs_log_item	*lip)
706 {
707 	struct xfs_inode_log_item *iip;
708 	struct xfs_log_item	*blip;
709 	struct xfs_log_item	*next;
710 	struct xfs_log_item	*prev;
711 	struct xfs_ail		*ailp = lip->li_ailp;
712 	int			need_ail = 0;
713 
714 	/*
715 	 * Scan the buffer IO completions for other inodes being completed and
716 	 * attach them to the current inode log item.
717 	 */
718 	blip = bp->b_fspriv;
719 	prev = NULL;
720 	while (blip != NULL) {
721 		if (lip->li_cb != xfs_iflush_done) {
722 			prev = blip;
723 			blip = blip->li_bio_list;
724 			continue;
725 		}
726 
727 		/* remove from list */
728 		next = blip->li_bio_list;
729 		if (!prev) {
730 			bp->b_fspriv = next;
731 		} else {
732 			prev->li_bio_list = next;
733 		}
734 
735 		/* add to current list */
736 		blip->li_bio_list = lip->li_bio_list;
737 		lip->li_bio_list = blip;
738 
739 		/*
740 		 * while we have the item, do the unlocked check for needing
741 		 * the AIL lock.
742 		 */
743 		iip = INODE_ITEM(blip);
744 		if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
745 			need_ail++;
746 
747 		blip = next;
748 	}
749 
750 	/* make sure we capture the state of the initial inode. */
751 	iip = INODE_ITEM(lip);
752 	if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
753 		need_ail++;
754 
755 	/*
756 	 * We only want to pull the item from the AIL if it is
757 	 * actually there and its location in the log has not
758 	 * changed since we started the flush.  Thus, we only bother
759 	 * if the ili_logged flag is set and the inode's lsn has not
760 	 * changed.  First we check the lsn outside
761 	 * the lock since it's cheaper, and then we recheck while
762 	 * holding the lock before removing the inode from the AIL.
763 	 */
764 	if (need_ail) {
765 		struct xfs_log_item *log_items[need_ail];
766 		int i = 0;
767 		spin_lock(&ailp->xa_lock);
768 		for (blip = lip; blip; blip = blip->li_bio_list) {
769 			iip = INODE_ITEM(blip);
770 			if (iip->ili_logged &&
771 			    blip->li_lsn == iip->ili_flush_lsn) {
772 				log_items[i++] = blip;
773 			}
774 			ASSERT(i <= need_ail);
775 		}
776 		/* xfs_trans_ail_delete_bulk() drops the AIL lock. */
777 		xfs_trans_ail_delete_bulk(ailp, log_items, i,
778 					  SHUTDOWN_CORRUPT_INCORE);
779 	}
780 
781 
782 	/*
783 	 * clean up and unlock the flush lock now we are done. We can clear the
784 	 * ili_last_fields bits now that we know that the data corresponding to
785 	 * them is safely on disk.
786 	 */
787 	for (blip = lip; blip; blip = next) {
788 		next = blip->li_bio_list;
789 		blip->li_bio_list = NULL;
790 
791 		iip = INODE_ITEM(blip);
792 		iip->ili_logged = 0;
793 		iip->ili_last_fields = 0;
794 		xfs_ifunlock(iip->ili_inode);
795 	}
796 }
797 
798 /*
799  * This is the inode flushing abort routine.  It is called from xfs_iflush when
800  * the filesystem is shutting down to clean up the inode state.  It is
801  * responsible for removing the inode item from the AIL if it has not been
802  * re-logged, and unlocking the inode's flush lock.
803  */
804 void
805 xfs_iflush_abort(
806 	xfs_inode_t		*ip,
807 	bool			stale)
808 {
809 	xfs_inode_log_item_t	*iip = ip->i_itemp;
810 
811 	if (iip) {
812 		struct xfs_ail	*ailp = iip->ili_item.li_ailp;
813 		if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
814 			spin_lock(&ailp->xa_lock);
815 			if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
816 				/* xfs_trans_ail_delete() drops the AIL lock. */
817 				xfs_trans_ail_delete(ailp, &iip->ili_item,
818 						stale ?
819 						     SHUTDOWN_LOG_IO_ERROR :
820 						     SHUTDOWN_CORRUPT_INCORE);
821 			} else
822 				spin_unlock(&ailp->xa_lock);
823 		}
824 		iip->ili_logged = 0;
825 		/*
826 		 * Clear the ili_last_fields bits now that we know that the
827 		 * data corresponding to them is safely on disk.
828 		 */
829 		iip->ili_last_fields = 0;
830 		/*
831 		 * Clear the inode logging fields so no more flushes are
832 		 * attempted.
833 		 */
834 		iip->ili_fields = 0;
835 	}
836 	/*
837 	 * Release the inode's flush lock since we're done with it.
838 	 */
839 	xfs_ifunlock(ip);
840 }
841 
842 void
843 xfs_istale_done(
844 	struct xfs_buf		*bp,
845 	struct xfs_log_item	*lip)
846 {
847 	xfs_iflush_abort(INODE_ITEM(lip)->ili_inode, true);
848 }
849 
850 /*
851  * convert an xfs_inode_log_format struct from either 32 or 64 bit versions
852  * (which can have different field alignments) to the native version
853  */
854 int
855 xfs_inode_item_format_convert(
856 	xfs_log_iovec_t		*buf,
857 	xfs_inode_log_format_t	*in_f)
858 {
859 	if (buf->i_len == sizeof(xfs_inode_log_format_32_t)) {
860 		xfs_inode_log_format_32_t *in_f32 = buf->i_addr;
861 
862 		in_f->ilf_type = in_f32->ilf_type;
863 		in_f->ilf_size = in_f32->ilf_size;
864 		in_f->ilf_fields = in_f32->ilf_fields;
865 		in_f->ilf_asize = in_f32->ilf_asize;
866 		in_f->ilf_dsize = in_f32->ilf_dsize;
867 		in_f->ilf_ino = in_f32->ilf_ino;
868 		/* copy biggest field of ilf_u */
869 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
870 		       in_f32->ilf_u.ilfu_uuid.__u_bits,
871 		       sizeof(uuid_t));
872 		in_f->ilf_blkno = in_f32->ilf_blkno;
873 		in_f->ilf_len = in_f32->ilf_len;
874 		in_f->ilf_boffset = in_f32->ilf_boffset;
875 		return 0;
876 	} else if (buf->i_len == sizeof(xfs_inode_log_format_64_t)){
877 		xfs_inode_log_format_64_t *in_f64 = buf->i_addr;
878 
879 		in_f->ilf_type = in_f64->ilf_type;
880 		in_f->ilf_size = in_f64->ilf_size;
881 		in_f->ilf_fields = in_f64->ilf_fields;
882 		in_f->ilf_asize = in_f64->ilf_asize;
883 		in_f->ilf_dsize = in_f64->ilf_dsize;
884 		in_f->ilf_ino = in_f64->ilf_ino;
885 		/* copy biggest field of ilf_u */
886 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
887 		       in_f64->ilf_u.ilfu_uuid.__u_bits,
888 		       sizeof(uuid_t));
889 		in_f->ilf_blkno = in_f64->ilf_blkno;
890 		in_f->ilf_len = in_f64->ilf_len;
891 		in_f->ilf_boffset = in_f64->ilf_boffset;
892 		return 0;
893 	}
894 	return EFSCORRUPTED;
895 }
896