xref: /linux/fs/xfs/xfs_inode_item.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_trans_priv.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_dinode.h"
31 #include "xfs_inode.h"
32 #include "xfs_inode_item.h"
33 #include "xfs_error.h"
34 #include "xfs_trace.h"
35 
36 
37 kmem_zone_t	*xfs_ili_zone;		/* inode log item zone */
38 
39 static inline struct xfs_inode_log_item *INODE_ITEM(struct xfs_log_item *lip)
40 {
41 	return container_of(lip, struct xfs_inode_log_item, ili_item);
42 }
43 
44 
45 /*
46  * This returns the number of iovecs needed to log the given inode item.
47  *
48  * We need one iovec for the inode log format structure, one for the
49  * inode core, and possibly one for the inode data/extents/b-tree root
50  * and one for the inode attribute data/extents/b-tree root.
51  */
52 STATIC uint
53 xfs_inode_item_size(
54 	struct xfs_log_item	*lip)
55 {
56 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
57 	struct xfs_inode	*ip = iip->ili_inode;
58 	uint			nvecs = 2;
59 
60 	/*
61 	 * Only log the data/extents/b-tree root if there is something
62 	 * left to log.
63 	 */
64 	iip->ili_format.ilf_fields |= XFS_ILOG_CORE;
65 
66 	switch (ip->i_d.di_format) {
67 	case XFS_DINODE_FMT_EXTENTS:
68 		iip->ili_format.ilf_fields &=
69 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
70 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
71 		if ((iip->ili_format.ilf_fields & XFS_ILOG_DEXT) &&
72 		    (ip->i_d.di_nextents > 0) &&
73 		    (ip->i_df.if_bytes > 0)) {
74 			ASSERT(ip->i_df.if_u1.if_extents != NULL);
75 			nvecs++;
76 		} else {
77 			iip->ili_format.ilf_fields &= ~XFS_ILOG_DEXT;
78 		}
79 		break;
80 
81 	case XFS_DINODE_FMT_BTREE:
82 		iip->ili_format.ilf_fields &=
83 			~(XFS_ILOG_DDATA | XFS_ILOG_DEXT |
84 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
85 		if ((iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) &&
86 		    (ip->i_df.if_broot_bytes > 0)) {
87 			ASSERT(ip->i_df.if_broot != NULL);
88 			nvecs++;
89 		} else {
90 			ASSERT(!(iip->ili_format.ilf_fields &
91 				 XFS_ILOG_DBROOT));
92 #ifdef XFS_TRANS_DEBUG
93 			if (iip->ili_root_size > 0) {
94 				ASSERT(iip->ili_root_size ==
95 				       ip->i_df.if_broot_bytes);
96 				ASSERT(memcmp(iip->ili_orig_root,
97 					    ip->i_df.if_broot,
98 					    iip->ili_root_size) == 0);
99 			} else {
100 				ASSERT(ip->i_df.if_broot_bytes == 0);
101 			}
102 #endif
103 			iip->ili_format.ilf_fields &= ~XFS_ILOG_DBROOT;
104 		}
105 		break;
106 
107 	case XFS_DINODE_FMT_LOCAL:
108 		iip->ili_format.ilf_fields &=
109 			~(XFS_ILOG_DEXT | XFS_ILOG_DBROOT |
110 			  XFS_ILOG_DEV | XFS_ILOG_UUID);
111 		if ((iip->ili_format.ilf_fields & XFS_ILOG_DDATA) &&
112 		    (ip->i_df.if_bytes > 0)) {
113 			ASSERT(ip->i_df.if_u1.if_data != NULL);
114 			ASSERT(ip->i_d.di_size > 0);
115 			nvecs++;
116 		} else {
117 			iip->ili_format.ilf_fields &= ~XFS_ILOG_DDATA;
118 		}
119 		break;
120 
121 	case XFS_DINODE_FMT_DEV:
122 		iip->ili_format.ilf_fields &=
123 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
124 			  XFS_ILOG_DEXT | XFS_ILOG_UUID);
125 		break;
126 
127 	case XFS_DINODE_FMT_UUID:
128 		iip->ili_format.ilf_fields &=
129 			~(XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
130 			  XFS_ILOG_DEXT | XFS_ILOG_DEV);
131 		break;
132 
133 	default:
134 		ASSERT(0);
135 		break;
136 	}
137 
138 	/*
139 	 * If there are no attributes associated with this file,
140 	 * then there cannot be anything more to log.
141 	 * Clear all attribute-related log flags.
142 	 */
143 	if (!XFS_IFORK_Q(ip)) {
144 		iip->ili_format.ilf_fields &=
145 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT);
146 		return nvecs;
147 	}
148 
149 	/*
150 	 * Log any necessary attribute data.
151 	 */
152 	switch (ip->i_d.di_aformat) {
153 	case XFS_DINODE_FMT_EXTENTS:
154 		iip->ili_format.ilf_fields &=
155 			~(XFS_ILOG_ADATA | XFS_ILOG_ABROOT);
156 		if ((iip->ili_format.ilf_fields & XFS_ILOG_AEXT) &&
157 		    (ip->i_d.di_anextents > 0) &&
158 		    (ip->i_afp->if_bytes > 0)) {
159 			ASSERT(ip->i_afp->if_u1.if_extents != NULL);
160 			nvecs++;
161 		} else {
162 			iip->ili_format.ilf_fields &= ~XFS_ILOG_AEXT;
163 		}
164 		break;
165 
166 	case XFS_DINODE_FMT_BTREE:
167 		iip->ili_format.ilf_fields &=
168 			~(XFS_ILOG_ADATA | XFS_ILOG_AEXT);
169 		if ((iip->ili_format.ilf_fields & XFS_ILOG_ABROOT) &&
170 		    (ip->i_afp->if_broot_bytes > 0)) {
171 			ASSERT(ip->i_afp->if_broot != NULL);
172 			nvecs++;
173 		} else {
174 			iip->ili_format.ilf_fields &= ~XFS_ILOG_ABROOT;
175 		}
176 		break;
177 
178 	case XFS_DINODE_FMT_LOCAL:
179 		iip->ili_format.ilf_fields &=
180 			~(XFS_ILOG_AEXT | XFS_ILOG_ABROOT);
181 		if ((iip->ili_format.ilf_fields & XFS_ILOG_ADATA) &&
182 		    (ip->i_afp->if_bytes > 0)) {
183 			ASSERT(ip->i_afp->if_u1.if_data != NULL);
184 			nvecs++;
185 		} else {
186 			iip->ili_format.ilf_fields &= ~XFS_ILOG_ADATA;
187 		}
188 		break;
189 
190 	default:
191 		ASSERT(0);
192 		break;
193 	}
194 
195 	return nvecs;
196 }
197 
198 /*
199  * xfs_inode_item_format_extents - convert in-core extents to on-disk form
200  *
201  * For either the data or attr fork in extent format, we need to endian convert
202  * the in-core extent as we place them into the on-disk inode. In this case, we
203  * need to do this conversion before we write the extents into the log. Because
204  * we don't have the disk inode to write into here, we allocate a buffer and
205  * format the extents into it via xfs_iextents_copy(). We free the buffer in
206  * the unlock routine after the copy for the log has been made.
207  *
208  * In the case of the data fork, the in-core and on-disk fork sizes can be
209  * different due to delayed allocation extents. We only log on-disk extents
210  * here, so always use the physical fork size to determine the size of the
211  * buffer we need to allocate.
212  */
213 STATIC void
214 xfs_inode_item_format_extents(
215 	struct xfs_inode	*ip,
216 	struct xfs_log_iovec	*vecp,
217 	int			whichfork,
218 	int			type)
219 {
220 	xfs_bmbt_rec_t		*ext_buffer;
221 
222 	ext_buffer = kmem_alloc(XFS_IFORK_SIZE(ip, whichfork), KM_SLEEP);
223 	if (whichfork == XFS_DATA_FORK)
224 		ip->i_itemp->ili_extents_buf = ext_buffer;
225 	else
226 		ip->i_itemp->ili_aextents_buf = ext_buffer;
227 
228 	vecp->i_addr = ext_buffer;
229 	vecp->i_len = xfs_iextents_copy(ip, ext_buffer, whichfork);
230 	vecp->i_type = type;
231 }
232 
233 /*
234  * This is called to fill in the vector of log iovecs for the
235  * given inode log item.  It fills the first item with an inode
236  * log format structure, the second with the on-disk inode structure,
237  * and a possible third and/or fourth with the inode data/extents/b-tree
238  * root and inode attributes data/extents/b-tree root.
239  */
240 STATIC void
241 xfs_inode_item_format(
242 	struct xfs_log_item	*lip,
243 	struct xfs_log_iovec	*vecp)
244 {
245 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
246 	struct xfs_inode	*ip = iip->ili_inode;
247 	uint			nvecs;
248 	size_t			data_bytes;
249 	xfs_mount_t		*mp;
250 
251 	vecp->i_addr = &iip->ili_format;
252 	vecp->i_len  = sizeof(xfs_inode_log_format_t);
253 	vecp->i_type = XLOG_REG_TYPE_IFORMAT;
254 	vecp++;
255 	nvecs	     = 1;
256 
257 	/*
258 	 * Clear i_update_core if the timestamps (or any other
259 	 * non-transactional modification) need flushing/logging
260 	 * and we're about to log them with the rest of the core.
261 	 *
262 	 * This is the same logic as xfs_iflush() but this code can't
263 	 * run at the same time as xfs_iflush because we're in commit
264 	 * processing here and so we have the inode lock held in
265 	 * exclusive mode.  Although it doesn't really matter
266 	 * for the timestamps if both routines were to grab the
267 	 * timestamps or not.  That would be ok.
268 	 *
269 	 * We clear i_update_core before copying out the data.
270 	 * This is for coordination with our timestamp updates
271 	 * that don't hold the inode lock. They will always
272 	 * update the timestamps BEFORE setting i_update_core,
273 	 * so if we clear i_update_core after they set it we
274 	 * are guaranteed to see their updates to the timestamps
275 	 * either here.  Likewise, if they set it after we clear it
276 	 * here, we'll see it either on the next commit of this
277 	 * inode or the next time the inode gets flushed via
278 	 * xfs_iflush().  This depends on strongly ordered memory
279 	 * semantics, but we have that.  We use the SYNCHRONIZE
280 	 * macro to make sure that the compiler does not reorder
281 	 * the i_update_core access below the data copy below.
282 	 */
283 	if (ip->i_update_core)  {
284 		ip->i_update_core = 0;
285 		SYNCHRONIZE();
286 	}
287 
288 	/*
289 	 * Make sure to get the latest timestamps from the Linux inode.
290 	 */
291 	xfs_synchronize_times(ip);
292 
293 	vecp->i_addr = &ip->i_d;
294 	vecp->i_len  = sizeof(struct xfs_icdinode);
295 	vecp->i_type = XLOG_REG_TYPE_ICORE;
296 	vecp++;
297 	nvecs++;
298 	iip->ili_format.ilf_fields |= XFS_ILOG_CORE;
299 
300 	/*
301 	 * If this is really an old format inode, then we need to
302 	 * log it as such.  This means that we have to copy the link
303 	 * count from the new field to the old.  We don't have to worry
304 	 * about the new fields, because nothing trusts them as long as
305 	 * the old inode version number is there.  If the superblock already
306 	 * has a new version number, then we don't bother converting back.
307 	 */
308 	mp = ip->i_mount;
309 	ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
310 	if (ip->i_d.di_version == 1) {
311 		if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
312 			/*
313 			 * Convert it back.
314 			 */
315 			ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
316 			ip->i_d.di_onlink = ip->i_d.di_nlink;
317 		} else {
318 			/*
319 			 * The superblock version has already been bumped,
320 			 * so just make the conversion to the new inode
321 			 * format permanent.
322 			 */
323 			ip->i_d.di_version = 2;
324 			ip->i_d.di_onlink = 0;
325 			memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
326 		}
327 	}
328 
329 	switch (ip->i_d.di_format) {
330 	case XFS_DINODE_FMT_EXTENTS:
331 		ASSERT(!(iip->ili_format.ilf_fields &
332 			 (XFS_ILOG_DDATA | XFS_ILOG_DBROOT |
333 			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
334 		if (iip->ili_format.ilf_fields & XFS_ILOG_DEXT) {
335 			ASSERT(ip->i_df.if_bytes > 0);
336 			ASSERT(ip->i_df.if_u1.if_extents != NULL);
337 			ASSERT(ip->i_d.di_nextents > 0);
338 			ASSERT(iip->ili_extents_buf == NULL);
339 			ASSERT((ip->i_df.if_bytes /
340 				(uint)sizeof(xfs_bmbt_rec_t)) > 0);
341 #ifdef XFS_NATIVE_HOST
342                        if (ip->i_d.di_nextents == ip->i_df.if_bytes /
343                                                (uint)sizeof(xfs_bmbt_rec_t)) {
344 				/*
345 				 * There are no delayed allocation
346 				 * extents, so just point to the
347 				 * real extents array.
348 				 */
349 				vecp->i_addr = ip->i_df.if_u1.if_extents;
350 				vecp->i_len = ip->i_df.if_bytes;
351 				vecp->i_type = XLOG_REG_TYPE_IEXT;
352 			} else
353 #endif
354 			{
355 				xfs_inode_item_format_extents(ip, vecp,
356 					XFS_DATA_FORK, XLOG_REG_TYPE_IEXT);
357 			}
358 			ASSERT(vecp->i_len <= ip->i_df.if_bytes);
359 			iip->ili_format.ilf_dsize = vecp->i_len;
360 			vecp++;
361 			nvecs++;
362 		}
363 		break;
364 
365 	case XFS_DINODE_FMT_BTREE:
366 		ASSERT(!(iip->ili_format.ilf_fields &
367 			 (XFS_ILOG_DDATA | XFS_ILOG_DEXT |
368 			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
369 		if (iip->ili_format.ilf_fields & XFS_ILOG_DBROOT) {
370 			ASSERT(ip->i_df.if_broot_bytes > 0);
371 			ASSERT(ip->i_df.if_broot != NULL);
372 			vecp->i_addr = ip->i_df.if_broot;
373 			vecp->i_len = ip->i_df.if_broot_bytes;
374 			vecp->i_type = XLOG_REG_TYPE_IBROOT;
375 			vecp++;
376 			nvecs++;
377 			iip->ili_format.ilf_dsize = ip->i_df.if_broot_bytes;
378 		}
379 		break;
380 
381 	case XFS_DINODE_FMT_LOCAL:
382 		ASSERT(!(iip->ili_format.ilf_fields &
383 			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
384 			  XFS_ILOG_DEV | XFS_ILOG_UUID)));
385 		if (iip->ili_format.ilf_fields & XFS_ILOG_DDATA) {
386 			ASSERT(ip->i_df.if_bytes > 0);
387 			ASSERT(ip->i_df.if_u1.if_data != NULL);
388 			ASSERT(ip->i_d.di_size > 0);
389 
390 			vecp->i_addr = ip->i_df.if_u1.if_data;
391 			/*
392 			 * Round i_bytes up to a word boundary.
393 			 * The underlying memory is guaranteed to
394 			 * to be there by xfs_idata_realloc().
395 			 */
396 			data_bytes = roundup(ip->i_df.if_bytes, 4);
397 			ASSERT((ip->i_df.if_real_bytes == 0) ||
398 			       (ip->i_df.if_real_bytes == data_bytes));
399 			vecp->i_len = (int)data_bytes;
400 			vecp->i_type = XLOG_REG_TYPE_ILOCAL;
401 			vecp++;
402 			nvecs++;
403 			iip->ili_format.ilf_dsize = (unsigned)data_bytes;
404 		}
405 		break;
406 
407 	case XFS_DINODE_FMT_DEV:
408 		ASSERT(!(iip->ili_format.ilf_fields &
409 			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
410 			  XFS_ILOG_DDATA | XFS_ILOG_UUID)));
411 		if (iip->ili_format.ilf_fields & XFS_ILOG_DEV) {
412 			iip->ili_format.ilf_u.ilfu_rdev =
413 				ip->i_df.if_u2.if_rdev;
414 		}
415 		break;
416 
417 	case XFS_DINODE_FMT_UUID:
418 		ASSERT(!(iip->ili_format.ilf_fields &
419 			 (XFS_ILOG_DBROOT | XFS_ILOG_DEXT |
420 			  XFS_ILOG_DDATA | XFS_ILOG_DEV)));
421 		if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
422 			iip->ili_format.ilf_u.ilfu_uuid =
423 				ip->i_df.if_u2.if_uuid;
424 		}
425 		break;
426 
427 	default:
428 		ASSERT(0);
429 		break;
430 	}
431 
432 	/*
433 	 * If there are no attributes associated with the file,
434 	 * then we're done.
435 	 * Assert that no attribute-related log flags are set.
436 	 */
437 	if (!XFS_IFORK_Q(ip)) {
438 		iip->ili_format.ilf_size = nvecs;
439 		ASSERT(!(iip->ili_format.ilf_fields &
440 			 (XFS_ILOG_ADATA | XFS_ILOG_ABROOT | XFS_ILOG_AEXT)));
441 		return;
442 	}
443 
444 	switch (ip->i_d.di_aformat) {
445 	case XFS_DINODE_FMT_EXTENTS:
446 		ASSERT(!(iip->ili_format.ilf_fields &
447 			 (XFS_ILOG_ADATA | XFS_ILOG_ABROOT)));
448 		if (iip->ili_format.ilf_fields & XFS_ILOG_AEXT) {
449 #ifdef DEBUG
450 			int nrecs = ip->i_afp->if_bytes /
451 				(uint)sizeof(xfs_bmbt_rec_t);
452 			ASSERT(nrecs > 0);
453 			ASSERT(nrecs == ip->i_d.di_anextents);
454 			ASSERT(ip->i_afp->if_bytes > 0);
455 			ASSERT(ip->i_afp->if_u1.if_extents != NULL);
456 			ASSERT(ip->i_d.di_anextents > 0);
457 #endif
458 #ifdef XFS_NATIVE_HOST
459 			/*
460 			 * There are not delayed allocation extents
461 			 * for attributes, so just point at the array.
462 			 */
463 			vecp->i_addr = ip->i_afp->if_u1.if_extents;
464 			vecp->i_len = ip->i_afp->if_bytes;
465 			vecp->i_type = XLOG_REG_TYPE_IATTR_EXT;
466 #else
467 			ASSERT(iip->ili_aextents_buf == NULL);
468 			xfs_inode_item_format_extents(ip, vecp,
469 					XFS_ATTR_FORK, XLOG_REG_TYPE_IATTR_EXT);
470 #endif
471 			iip->ili_format.ilf_asize = vecp->i_len;
472 			vecp++;
473 			nvecs++;
474 		}
475 		break;
476 
477 	case XFS_DINODE_FMT_BTREE:
478 		ASSERT(!(iip->ili_format.ilf_fields &
479 			 (XFS_ILOG_ADATA | XFS_ILOG_AEXT)));
480 		if (iip->ili_format.ilf_fields & XFS_ILOG_ABROOT) {
481 			ASSERT(ip->i_afp->if_broot_bytes > 0);
482 			ASSERT(ip->i_afp->if_broot != NULL);
483 			vecp->i_addr = ip->i_afp->if_broot;
484 			vecp->i_len = ip->i_afp->if_broot_bytes;
485 			vecp->i_type = XLOG_REG_TYPE_IATTR_BROOT;
486 			vecp++;
487 			nvecs++;
488 			iip->ili_format.ilf_asize = ip->i_afp->if_broot_bytes;
489 		}
490 		break;
491 
492 	case XFS_DINODE_FMT_LOCAL:
493 		ASSERT(!(iip->ili_format.ilf_fields &
494 			 (XFS_ILOG_ABROOT | XFS_ILOG_AEXT)));
495 		if (iip->ili_format.ilf_fields & XFS_ILOG_ADATA) {
496 			ASSERT(ip->i_afp->if_bytes > 0);
497 			ASSERT(ip->i_afp->if_u1.if_data != NULL);
498 
499 			vecp->i_addr = ip->i_afp->if_u1.if_data;
500 			/*
501 			 * Round i_bytes up to a word boundary.
502 			 * The underlying memory is guaranteed to
503 			 * to be there by xfs_idata_realloc().
504 			 */
505 			data_bytes = roundup(ip->i_afp->if_bytes, 4);
506 			ASSERT((ip->i_afp->if_real_bytes == 0) ||
507 			       (ip->i_afp->if_real_bytes == data_bytes));
508 			vecp->i_len = (int)data_bytes;
509 			vecp->i_type = XLOG_REG_TYPE_IATTR_LOCAL;
510 			vecp++;
511 			nvecs++;
512 			iip->ili_format.ilf_asize = (unsigned)data_bytes;
513 		}
514 		break;
515 
516 	default:
517 		ASSERT(0);
518 		break;
519 	}
520 
521 	iip->ili_format.ilf_size = nvecs;
522 }
523 
524 
525 /*
526  * This is called to pin the inode associated with the inode log
527  * item in memory so it cannot be written out.
528  */
529 STATIC void
530 xfs_inode_item_pin(
531 	struct xfs_log_item	*lip)
532 {
533 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;
534 
535 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
536 
537 	trace_xfs_inode_pin(ip, _RET_IP_);
538 	atomic_inc(&ip->i_pincount);
539 }
540 
541 
542 /*
543  * This is called to unpin the inode associated with the inode log
544  * item which was previously pinned with a call to xfs_inode_item_pin().
545  *
546  * Also wake up anyone in xfs_iunpin_wait() if the count goes to 0.
547  */
548 STATIC void
549 xfs_inode_item_unpin(
550 	struct xfs_log_item	*lip,
551 	int			remove)
552 {
553 	struct xfs_inode	*ip = INODE_ITEM(lip)->ili_inode;
554 
555 	trace_xfs_inode_unpin(ip, _RET_IP_);
556 	ASSERT(atomic_read(&ip->i_pincount) > 0);
557 	if (atomic_dec_and_test(&ip->i_pincount))
558 		wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
559 }
560 
561 /*
562  * This is called to attempt to lock the inode associated with this
563  * inode log item, in preparation for the push routine which does the actual
564  * iflush.  Don't sleep on the inode lock or the flush lock.
565  *
566  * If the flush lock is already held, indicating that the inode has
567  * been or is in the process of being flushed, then (ideally) we'd like to
568  * see if the inode's buffer is still incore, and if so give it a nudge.
569  * We delay doing so until the pushbuf routine, though, to avoid holding
570  * the AIL lock across a call to the blackhole which is the buffer cache.
571  * Also we don't want to sleep in any device strategy routines, which can happen
572  * if we do the subsequent bawrite in here.
573  */
574 STATIC uint
575 xfs_inode_item_trylock(
576 	struct xfs_log_item	*lip)
577 {
578 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
579 	struct xfs_inode	*ip = iip->ili_inode;
580 
581 	if (xfs_ipincount(ip) > 0)
582 		return XFS_ITEM_PINNED;
583 
584 	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
585 		return XFS_ITEM_LOCKED;
586 
587 	if (!xfs_iflock_nowait(ip)) {
588 		/*
589 		 * inode has already been flushed to the backing buffer,
590 		 * leave it locked in shared mode, pushbuf routine will
591 		 * unlock it.
592 		 */
593 		return XFS_ITEM_PUSHBUF;
594 	}
595 
596 	/* Stale items should force out the iclog */
597 	if (ip->i_flags & XFS_ISTALE) {
598 		xfs_ifunlock(ip);
599 		/*
600 		 * we hold the AIL lock - notify the unlock routine of this
601 		 * so it doesn't try to get the lock again.
602 		 */
603 		xfs_iunlock(ip, XFS_ILOCK_SHARED|XFS_IUNLOCK_NONOTIFY);
604 		return XFS_ITEM_PINNED;
605 	}
606 
607 #ifdef DEBUG
608 	if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
609 		ASSERT(iip->ili_format.ilf_fields != 0);
610 		ASSERT(iip->ili_logged == 0);
611 		ASSERT(lip->li_flags & XFS_LI_IN_AIL);
612 	}
613 #endif
614 	return XFS_ITEM_SUCCESS;
615 }
616 
617 /*
618  * Unlock the inode associated with the inode log item.
619  * Clear the fields of the inode and inode log item that
620  * are specific to the current transaction.  If the
621  * hold flags is set, do not unlock the inode.
622  */
623 STATIC void
624 xfs_inode_item_unlock(
625 	struct xfs_log_item	*lip)
626 {
627 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
628 	struct xfs_inode	*ip = iip->ili_inode;
629 	unsigned short		lock_flags;
630 
631 	ASSERT(ip->i_itemp != NULL);
632 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
633 
634 	/*
635 	 * If the inode needed a separate buffer with which to log
636 	 * its extents, then free it now.
637 	 */
638 	if (iip->ili_extents_buf != NULL) {
639 		ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS);
640 		ASSERT(ip->i_d.di_nextents > 0);
641 		ASSERT(iip->ili_format.ilf_fields & XFS_ILOG_DEXT);
642 		ASSERT(ip->i_df.if_bytes > 0);
643 		kmem_free(iip->ili_extents_buf);
644 		iip->ili_extents_buf = NULL;
645 	}
646 	if (iip->ili_aextents_buf != NULL) {
647 		ASSERT(ip->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS);
648 		ASSERT(ip->i_d.di_anextents > 0);
649 		ASSERT(iip->ili_format.ilf_fields & XFS_ILOG_AEXT);
650 		ASSERT(ip->i_afp->if_bytes > 0);
651 		kmem_free(iip->ili_aextents_buf);
652 		iip->ili_aextents_buf = NULL;
653 	}
654 
655 	lock_flags = iip->ili_lock_flags;
656 	iip->ili_lock_flags = 0;
657 	if (lock_flags)
658 		xfs_iunlock(ip, lock_flags);
659 }
660 
661 /*
662  * This is called to find out where the oldest active copy of the inode log
663  * item in the on disk log resides now that the last log write of it completed
664  * at the given lsn.  Since we always re-log all dirty data in an inode, the
665  * latest copy in the on disk log is the only one that matters.  Therefore,
666  * simply return the given lsn.
667  *
668  * If the inode has been marked stale because the cluster is being freed, we
669  * don't want to (re-)insert this inode into the AIL. There is a race condition
670  * where the cluster buffer may be unpinned before the inode is inserted into
671  * the AIL during transaction committed processing. If the buffer is unpinned
672  * before the inode item has been committed and inserted, then it is possible
673  * for the buffer to be written and IO completes before the inode is inserted
674  * into the AIL. In that case, we'd be inserting a clean, stale inode into the
675  * AIL which will never get removed. It will, however, get reclaimed which
676  * triggers an assert in xfs_inode_free() complaining about freein an inode
677  * still in the AIL.
678  *
679  * To avoid this, just unpin the inode directly and return a LSN of -1 so the
680  * transaction committed code knows that it does not need to do any further
681  * processing on the item.
682  */
683 STATIC xfs_lsn_t
684 xfs_inode_item_committed(
685 	struct xfs_log_item	*lip,
686 	xfs_lsn_t		lsn)
687 {
688 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
689 	struct xfs_inode	*ip = iip->ili_inode;
690 
691 	if (xfs_iflags_test(ip, XFS_ISTALE)) {
692 		xfs_inode_item_unpin(lip, 0);
693 		return -1;
694 	}
695 	return lsn;
696 }
697 
698 /*
699  * This gets called by xfs_trans_push_ail(), when IOP_TRYLOCK
700  * failed to get the inode flush lock but did get the inode locked SHARED.
701  * Here we're trying to see if the inode buffer is incore, and if so whether it's
702  * marked delayed write. If that's the case, we'll promote it and that will
703  * allow the caller to write the buffer by triggering the xfsbufd to run.
704  */
705 STATIC bool
706 xfs_inode_item_pushbuf(
707 	struct xfs_log_item	*lip)
708 {
709 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
710 	struct xfs_inode	*ip = iip->ili_inode;
711 	struct xfs_buf		*bp;
712 	bool			ret = true;
713 
714 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
715 
716 	/*
717 	 * If a flush is not in progress anymore, chances are that the
718 	 * inode was taken off the AIL. So, just get out.
719 	 */
720 	if (!xfs_isiflocked(ip) ||
721 	    !(lip->li_flags & XFS_LI_IN_AIL)) {
722 		xfs_iunlock(ip, XFS_ILOCK_SHARED);
723 		return true;
724 	}
725 
726 	bp = xfs_incore(ip->i_mount->m_ddev_targp, iip->ili_format.ilf_blkno,
727 			iip->ili_format.ilf_len, XBF_TRYLOCK);
728 
729 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
730 	if (!bp)
731 		return true;
732 	if (XFS_BUF_ISDELAYWRITE(bp))
733 		xfs_buf_delwri_promote(bp);
734 	if (xfs_buf_ispinned(bp))
735 		ret = false;
736 	xfs_buf_relse(bp);
737 	return ret;
738 }
739 
740 /*
741  * This is called to asynchronously write the inode associated with this
742  * inode log item out to disk. The inode will already have been locked by
743  * a successful call to xfs_inode_item_trylock().
744  */
745 STATIC void
746 xfs_inode_item_push(
747 	struct xfs_log_item	*lip)
748 {
749 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
750 	struct xfs_inode	*ip = iip->ili_inode;
751 
752 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED));
753 	ASSERT(xfs_isiflocked(ip));
754 
755 	/*
756 	 * Since we were able to lock the inode's flush lock and
757 	 * we found it on the AIL, the inode must be dirty.  This
758 	 * is because the inode is removed from the AIL while still
759 	 * holding the flush lock in xfs_iflush_done().  Thus, if
760 	 * we found it in the AIL and were able to obtain the flush
761 	 * lock without sleeping, then there must not have been
762 	 * anyone in the process of flushing the inode.
763 	 */
764 	ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) ||
765 	       iip->ili_format.ilf_fields != 0);
766 
767 	/*
768 	 * Push the inode to it's backing buffer. This will not remove the
769 	 * inode from the AIL - a further push will be required to trigger a
770 	 * buffer push. However, this allows all the dirty inodes to be pushed
771 	 * to the buffer before it is pushed to disk. The buffer IO completion
772 	 * will pull the inode from the AIL, mark it clean and unlock the flush
773 	 * lock.
774 	 */
775 	(void) xfs_iflush(ip, SYNC_TRYLOCK);
776 	xfs_iunlock(ip, XFS_ILOCK_SHARED);
777 }
778 
779 /*
780  * XXX rcc - this one really has to do something.  Probably needs
781  * to stamp in a new field in the incore inode.
782  */
783 STATIC void
784 xfs_inode_item_committing(
785 	struct xfs_log_item	*lip,
786 	xfs_lsn_t		lsn)
787 {
788 	INODE_ITEM(lip)->ili_last_lsn = lsn;
789 }
790 
791 /*
792  * This is the ops vector shared by all buf log items.
793  */
794 static const struct xfs_item_ops xfs_inode_item_ops = {
795 	.iop_size	= xfs_inode_item_size,
796 	.iop_format	= xfs_inode_item_format,
797 	.iop_pin	= xfs_inode_item_pin,
798 	.iop_unpin	= xfs_inode_item_unpin,
799 	.iop_trylock	= xfs_inode_item_trylock,
800 	.iop_unlock	= xfs_inode_item_unlock,
801 	.iop_committed	= xfs_inode_item_committed,
802 	.iop_push	= xfs_inode_item_push,
803 	.iop_pushbuf	= xfs_inode_item_pushbuf,
804 	.iop_committing = xfs_inode_item_committing
805 };
806 
807 
808 /*
809  * Initialize the inode log item for a newly allocated (in-core) inode.
810  */
811 void
812 xfs_inode_item_init(
813 	struct xfs_inode	*ip,
814 	struct xfs_mount	*mp)
815 {
816 	struct xfs_inode_log_item *iip;
817 
818 	ASSERT(ip->i_itemp == NULL);
819 	iip = ip->i_itemp = kmem_zone_zalloc(xfs_ili_zone, KM_SLEEP);
820 
821 	iip->ili_inode = ip;
822 	xfs_log_item_init(mp, &iip->ili_item, XFS_LI_INODE,
823 						&xfs_inode_item_ops);
824 	iip->ili_format.ilf_type = XFS_LI_INODE;
825 	iip->ili_format.ilf_ino = ip->i_ino;
826 	iip->ili_format.ilf_blkno = ip->i_imap.im_blkno;
827 	iip->ili_format.ilf_len = ip->i_imap.im_len;
828 	iip->ili_format.ilf_boffset = ip->i_imap.im_boffset;
829 }
830 
831 /*
832  * Free the inode log item and any memory hanging off of it.
833  */
834 void
835 xfs_inode_item_destroy(
836 	xfs_inode_t	*ip)
837 {
838 #ifdef XFS_TRANS_DEBUG
839 	if (ip->i_itemp->ili_root_size != 0) {
840 		kmem_free(ip->i_itemp->ili_orig_root);
841 	}
842 #endif
843 	kmem_zone_free(xfs_ili_zone, ip->i_itemp);
844 }
845 
846 
847 /*
848  * This is the inode flushing I/O completion routine.  It is called
849  * from interrupt level when the buffer containing the inode is
850  * flushed to disk.  It is responsible for removing the inode item
851  * from the AIL if it has not been re-logged, and unlocking the inode's
852  * flush lock.
853  *
854  * To reduce AIL lock traffic as much as possible, we scan the buffer log item
855  * list for other inodes that will run this function. We remove them from the
856  * buffer list so we can process all the inode IO completions in one AIL lock
857  * traversal.
858  */
859 void
860 xfs_iflush_done(
861 	struct xfs_buf		*bp,
862 	struct xfs_log_item	*lip)
863 {
864 	struct xfs_inode_log_item *iip;
865 	struct xfs_log_item	*blip;
866 	struct xfs_log_item	*next;
867 	struct xfs_log_item	*prev;
868 	struct xfs_ail		*ailp = lip->li_ailp;
869 	int			need_ail = 0;
870 
871 	/*
872 	 * Scan the buffer IO completions for other inodes being completed and
873 	 * attach them to the current inode log item.
874 	 */
875 	blip = bp->b_fspriv;
876 	prev = NULL;
877 	while (blip != NULL) {
878 		if (lip->li_cb != xfs_iflush_done) {
879 			prev = blip;
880 			blip = blip->li_bio_list;
881 			continue;
882 		}
883 
884 		/* remove from list */
885 		next = blip->li_bio_list;
886 		if (!prev) {
887 			bp->b_fspriv = next;
888 		} else {
889 			prev->li_bio_list = next;
890 		}
891 
892 		/* add to current list */
893 		blip->li_bio_list = lip->li_bio_list;
894 		lip->li_bio_list = blip;
895 
896 		/*
897 		 * while we have the item, do the unlocked check for needing
898 		 * the AIL lock.
899 		 */
900 		iip = INODE_ITEM(blip);
901 		if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
902 			need_ail++;
903 
904 		blip = next;
905 	}
906 
907 	/* make sure we capture the state of the initial inode. */
908 	iip = INODE_ITEM(lip);
909 	if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
910 		need_ail++;
911 
912 	/*
913 	 * We only want to pull the item from the AIL if it is
914 	 * actually there and its location in the log has not
915 	 * changed since we started the flush.  Thus, we only bother
916 	 * if the ili_logged flag is set and the inode's lsn has not
917 	 * changed.  First we check the lsn outside
918 	 * the lock since it's cheaper, and then we recheck while
919 	 * holding the lock before removing the inode from the AIL.
920 	 */
921 	if (need_ail) {
922 		struct xfs_log_item *log_items[need_ail];
923 		int i = 0;
924 		spin_lock(&ailp->xa_lock);
925 		for (blip = lip; blip; blip = blip->li_bio_list) {
926 			iip = INODE_ITEM(blip);
927 			if (iip->ili_logged &&
928 			    blip->li_lsn == iip->ili_flush_lsn) {
929 				log_items[i++] = blip;
930 			}
931 			ASSERT(i <= need_ail);
932 		}
933 		/* xfs_trans_ail_delete_bulk() drops the AIL lock. */
934 		xfs_trans_ail_delete_bulk(ailp, log_items, i);
935 	}
936 
937 
938 	/*
939 	 * clean up and unlock the flush lock now we are done. We can clear the
940 	 * ili_last_fields bits now that we know that the data corresponding to
941 	 * them is safely on disk.
942 	 */
943 	for (blip = lip; blip; blip = next) {
944 		next = blip->li_bio_list;
945 		blip->li_bio_list = NULL;
946 
947 		iip = INODE_ITEM(blip);
948 		iip->ili_logged = 0;
949 		iip->ili_last_fields = 0;
950 		xfs_ifunlock(iip->ili_inode);
951 	}
952 }
953 
954 /*
955  * This is the inode flushing abort routine.  It is called
956  * from xfs_iflush when the filesystem is shutting down to clean
957  * up the inode state.
958  * It is responsible for removing the inode item
959  * from the AIL if it has not been re-logged, and unlocking the inode's
960  * flush lock.
961  */
962 void
963 xfs_iflush_abort(
964 	xfs_inode_t		*ip)
965 {
966 	xfs_inode_log_item_t	*iip = ip->i_itemp;
967 
968 	if (iip) {
969 		struct xfs_ail	*ailp = iip->ili_item.li_ailp;
970 		if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
971 			spin_lock(&ailp->xa_lock);
972 			if (iip->ili_item.li_flags & XFS_LI_IN_AIL) {
973 				/* xfs_trans_ail_delete() drops the AIL lock. */
974 				xfs_trans_ail_delete(ailp, (xfs_log_item_t *)iip);
975 			} else
976 				spin_unlock(&ailp->xa_lock);
977 		}
978 		iip->ili_logged = 0;
979 		/*
980 		 * Clear the ili_last_fields bits now that we know that the
981 		 * data corresponding to them is safely on disk.
982 		 */
983 		iip->ili_last_fields = 0;
984 		/*
985 		 * Clear the inode logging fields so no more flushes are
986 		 * attempted.
987 		 */
988 		iip->ili_format.ilf_fields = 0;
989 	}
990 	/*
991 	 * Release the inode's flush lock since we're done with it.
992 	 */
993 	xfs_ifunlock(ip);
994 }
995 
996 void
997 xfs_istale_done(
998 	struct xfs_buf		*bp,
999 	struct xfs_log_item	*lip)
1000 {
1001 	xfs_iflush_abort(INODE_ITEM(lip)->ili_inode);
1002 }
1003 
1004 /*
1005  * convert an xfs_inode_log_format struct from either 32 or 64 bit versions
1006  * (which can have different field alignments) to the native version
1007  */
1008 int
1009 xfs_inode_item_format_convert(
1010 	xfs_log_iovec_t		*buf,
1011 	xfs_inode_log_format_t	*in_f)
1012 {
1013 	if (buf->i_len == sizeof(xfs_inode_log_format_32_t)) {
1014 		xfs_inode_log_format_32_t *in_f32 = buf->i_addr;
1015 
1016 		in_f->ilf_type = in_f32->ilf_type;
1017 		in_f->ilf_size = in_f32->ilf_size;
1018 		in_f->ilf_fields = in_f32->ilf_fields;
1019 		in_f->ilf_asize = in_f32->ilf_asize;
1020 		in_f->ilf_dsize = in_f32->ilf_dsize;
1021 		in_f->ilf_ino = in_f32->ilf_ino;
1022 		/* copy biggest field of ilf_u */
1023 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
1024 		       in_f32->ilf_u.ilfu_uuid.__u_bits,
1025 		       sizeof(uuid_t));
1026 		in_f->ilf_blkno = in_f32->ilf_blkno;
1027 		in_f->ilf_len = in_f32->ilf_len;
1028 		in_f->ilf_boffset = in_f32->ilf_boffset;
1029 		return 0;
1030 	} else if (buf->i_len == sizeof(xfs_inode_log_format_64_t)){
1031 		xfs_inode_log_format_64_t *in_f64 = buf->i_addr;
1032 
1033 		in_f->ilf_type = in_f64->ilf_type;
1034 		in_f->ilf_size = in_f64->ilf_size;
1035 		in_f->ilf_fields = in_f64->ilf_fields;
1036 		in_f->ilf_asize = in_f64->ilf_asize;
1037 		in_f->ilf_dsize = in_f64->ilf_dsize;
1038 		in_f->ilf_ino = in_f64->ilf_ino;
1039 		/* copy biggest field of ilf_u */
1040 		memcpy(in_f->ilf_u.ilfu_uuid.__u_bits,
1041 		       in_f64->ilf_u.ilfu_uuid.__u_bits,
1042 		       sizeof(uuid_t));
1043 		in_f->ilf_blkno = in_f64->ilf_blkno;
1044 		in_f->ilf_len = in_f64->ilf_len;
1045 		in_f->ilf_boffset = in_f64->ilf_boffset;
1046 		return 0;
1047 	}
1048 	return EFSCORRUPTED;
1049 }
1050