xref: /linux/fs/xfs/libxfs/xfs_trans_resv.c (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4  * Copyright (C) 2010 Red Hat, Inc.
5  * All Rights Reserved.
6  */
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_shared.h"
10 #include "xfs_format.h"
11 #include "xfs_log_format.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_mount.h"
14 #include "xfs_da_format.h"
15 #include "xfs_da_btree.h"
16 #include "xfs_inode.h"
17 #include "xfs_bmap_btree.h"
18 #include "xfs_quota.h"
19 #include "xfs_trans.h"
20 #include "xfs_qm.h"
21 #include "xfs_trans_space.h"
22 
23 #define _ALLOC	true
24 #define _FREE	false
25 
26 /*
27  * A buffer has a format structure overhead in the log in addition
28  * to the data, so we need to take this into account when reserving
29  * space in a transaction for a buffer.  Round the space required up
30  * to a multiple of 128 bytes so that we don't change the historical
31  * reservation that has been used for this overhead.
32  */
33 STATIC uint
34 xfs_buf_log_overhead(void)
35 {
36 	return round_up(sizeof(struct xlog_op_header) +
37 			sizeof(struct xfs_buf_log_format), 128);
38 }
39 
40 /*
41  * Calculate out transaction log reservation per item in bytes.
42  *
43  * The nbufs argument is used to indicate the number of items that
44  * will be changed in a transaction.  size is used to tell how many
45  * bytes should be reserved per item.
46  */
47 STATIC uint
48 xfs_calc_buf_res(
49 	uint		nbufs,
50 	uint		size)
51 {
52 	return nbufs * (size + xfs_buf_log_overhead());
53 }
54 
55 /*
56  * Per-extent log reservation for the btree changes involved in freeing or
57  * allocating an extent.  In classic XFS there were two trees that will be
58  * modified (bnobt + cntbt).  With rmap enabled, there are three trees
59  * (rmapbt).  The number of blocks reserved is based on the formula:
60  *
61  * num trees * ((2 blocks/level * max depth) - 1)
62  *
63  * Keep in mind that max depth is calculated separately for each type of tree.
64  */
65 uint
66 xfs_allocfree_block_count(
67 	struct xfs_mount *mp,
68 	uint		num_ops)
69 {
70 	uint		blocks;
71 
72 	blocks = num_ops * 2 * (2 * mp->m_alloc_maxlevels - 1);
73 	if (xfs_has_rmapbt(mp))
74 		blocks += num_ops * (2 * mp->m_rmap_maxlevels - 1);
75 
76 	return blocks;
77 }
78 
79 /*
80  * Per-extent log reservation for refcount btree changes.  These are never done
81  * in the same transaction as an allocation or a free, so we compute them
82  * separately.
83  */
84 static unsigned int
85 xfs_refcountbt_block_count(
86 	struct xfs_mount	*mp,
87 	unsigned int		num_ops)
88 {
89 	return num_ops * (2 * mp->m_refc_maxlevels - 1);
90 }
91 
92 /*
93  * Logging inodes is really tricksy. They are logged in memory format,
94  * which means that what we write into the log doesn't directly translate into
95  * the amount of space they use on disk.
96  *
97  * Case in point - btree format forks in memory format use more space than the
98  * on-disk format. In memory, the buffer contains a normal btree block header so
99  * the btree code can treat it as though it is just another generic buffer.
100  * However, when we write it to the inode fork, we don't write all of this
101  * header as it isn't needed. e.g. the root is only ever in the inode, so
102  * there's no need for sibling pointers which would waste 16 bytes of space.
103  *
104  * Hence when we have an inode with a maximally sized btree format fork, then
105  * amount of information we actually log is greater than the size of the inode
106  * on disk. Hence we need an inode reservation function that calculates all this
107  * correctly. So, we log:
108  *
109  * - 4 log op headers for object
110  *	- for the ilf, the inode core and 2 forks
111  * - inode log format object
112  * - the inode core
113  * - two inode forks containing bmap btree root blocks.
114  *	- the btree data contained by both forks will fit into the inode size,
115  *	  hence when combined with the inode core above, we have a total of the
116  *	  actual inode size.
117  *	- the BMBT headers need to be accounted separately, as they are
118  *	  additional to the records and pointers that fit inside the inode
119  *	  forks.
120  */
121 STATIC uint
122 xfs_calc_inode_res(
123 	struct xfs_mount	*mp,
124 	uint			ninodes)
125 {
126 	return ninodes *
127 		(4 * sizeof(struct xlog_op_header) +
128 		 sizeof(struct xfs_inode_log_format) +
129 		 mp->m_sb.sb_inodesize +
130 		 2 * XFS_BMBT_BLOCK_LEN(mp));
131 }
132 
133 /*
134  * Inode btree record insertion/removal modifies the inode btree and free space
135  * btrees (since the inobt does not use the agfl). This requires the following
136  * reservation:
137  *
138  * the inode btree: max depth * blocksize
139  * the allocation btrees: 2 trees * (max depth - 1) * block size
140  *
141  * The caller must account for SB and AG header modifications, etc.
142  */
143 STATIC uint
144 xfs_calc_inobt_res(
145 	struct xfs_mount	*mp)
146 {
147 	return xfs_calc_buf_res(M_IGEO(mp)->inobt_maxlevels,
148 			XFS_FSB_TO_B(mp, 1)) +
149 				xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
150 			XFS_FSB_TO_B(mp, 1));
151 }
152 
153 /*
154  * The free inode btree is a conditional feature. The behavior differs slightly
155  * from that of the traditional inode btree in that the finobt tracks records
156  * for inode chunks with at least one free inode. A record can be removed from
157  * the tree during individual inode allocation. Therefore the finobt
158  * reservation is unconditional for both the inode chunk allocation and
159  * individual inode allocation (modify) cases.
160  *
161  * Behavior aside, the reservation for finobt modification is equivalent to the
162  * traditional inobt: cover a full finobt shape change plus block allocation.
163  */
164 STATIC uint
165 xfs_calc_finobt_res(
166 	struct xfs_mount	*mp)
167 {
168 	if (!xfs_has_finobt(mp))
169 		return 0;
170 
171 	return xfs_calc_inobt_res(mp);
172 }
173 
174 /*
175  * Calculate the reservation required to allocate or free an inode chunk. This
176  * includes:
177  *
178  * the allocation btrees: 2 trees * (max depth - 1) * block size
179  * the inode chunk: m_ino_geo.ialloc_blks * N
180  *
181  * The size N of the inode chunk reservation depends on whether it is for
182  * allocation or free and which type of create transaction is in use. An inode
183  * chunk free always invalidates the buffers and only requires reservation for
184  * headers (N == 0). An inode chunk allocation requires a chunk sized
185  * reservation on v4 and older superblocks to initialize the chunk. No chunk
186  * reservation is required for allocation on v5 supers, which use ordered
187  * buffers to initialize.
188  */
189 STATIC uint
190 xfs_calc_inode_chunk_res(
191 	struct xfs_mount	*mp,
192 	bool			alloc)
193 {
194 	uint			res, size = 0;
195 
196 	res = xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
197 			       XFS_FSB_TO_B(mp, 1));
198 	if (alloc) {
199 		/* icreate tx uses ordered buffers */
200 		if (xfs_has_v3inodes(mp))
201 			return res;
202 		size = XFS_FSB_TO_B(mp, 1);
203 	}
204 
205 	res += xfs_calc_buf_res(M_IGEO(mp)->ialloc_blks, size);
206 	return res;
207 }
208 
209 /*
210  * Per-extent log reservation for the btree changes involved in freeing or
211  * allocating a realtime extent.  We have to be able to log as many rtbitmap
212  * blocks as needed to mark inuse XFS_BMBT_MAX_EXTLEN blocks' worth of realtime
213  * extents, as well as the realtime summary block.
214  */
215 static unsigned int
216 xfs_rtalloc_block_count(
217 	struct xfs_mount	*mp,
218 	unsigned int		num_ops)
219 {
220 	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
221 	unsigned int		rtbmp_bytes;
222 
223 	rtbmp_bytes = (XFS_MAX_BMBT_EXTLEN / mp->m_sb.sb_rextsize) / NBBY;
224 	return (howmany(rtbmp_bytes, blksz) + 1) * num_ops;
225 }
226 
227 /*
228  * Various log reservation values.
229  *
230  * These are based on the size of the file system block because that is what
231  * most transactions manipulate.  Each adds in an additional 128 bytes per
232  * item logged to try to account for the overhead of the transaction mechanism.
233  *
234  * Note:  Most of the reservations underestimate the number of allocation
235  * groups into which they could free extents in the xfs_defer_finish() call.
236  * This is because the number in the worst case is quite high and quite
237  * unusual.  In order to fix this we need to change xfs_defer_finish() to free
238  * extents in only a single AG at a time.  This will require changes to the
239  * EFI code as well, however, so that the EFI for the extents not freed is
240  * logged again in each transaction.  See SGI PV #261917.
241  *
242  * Reservation functions here avoid a huge stack in xfs_trans_init due to
243  * register overflow from temporaries in the calculations.
244  */
245 
246 /*
247  * Compute the log reservation required to handle the refcount update
248  * transaction.  Refcount updates are always done via deferred log items.
249  *
250  * This is calculated as:
251  * Data device refcount updates (t1):
252  *    the agfs of the ags containing the blocks: nr_ops * sector size
253  *    the refcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
254  */
255 static unsigned int
256 xfs_calc_refcountbt_reservation(
257 	struct xfs_mount	*mp,
258 	unsigned int		nr_ops)
259 {
260 	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
261 
262 	if (!xfs_has_reflink(mp))
263 		return 0;
264 
265 	return xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
266 	       xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops), blksz);
267 }
268 
269 /*
270  * In a write transaction we can allocate a maximum of 2
271  * extents.  This gives (t1):
272  *    the inode getting the new extents: inode size
273  *    the inode's bmap btree: max depth * block size
274  *    the agfs of the ags from which the extents are allocated: 2 * sector
275  *    the superblock free block counter: sector size
276  *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
277  * Or, if we're writing to a realtime file (t2):
278  *    the inode getting the new extents: inode size
279  *    the inode's bmap btree: max depth * block size
280  *    the agfs of the ags from which the extents are allocated: 2 * sector
281  *    the superblock free block counter: sector size
282  *    the realtime bitmap: ((XFS_BMBT_MAX_EXTLEN / rtextsize) / NBBY) bytes
283  *    the realtime summary: 1 block
284  *    the allocation btrees: 2 trees * (2 * max depth - 1) * block size
285  * And the bmap_finish transaction can free bmap blocks in a join (t3):
286  *    the agfs of the ags containing the blocks: 2 * sector size
287  *    the agfls of the ags containing the blocks: 2 * sector size
288  *    the super block free block counter: sector size
289  *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
290  * And any refcount updates that happen in a separate transaction (t4).
291  */
292 STATIC uint
293 xfs_calc_write_reservation(
294 	struct xfs_mount	*mp,
295 	bool			for_minlogsize)
296 {
297 	unsigned int		t1, t2, t3, t4;
298 	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
299 
300 	t1 = xfs_calc_inode_res(mp, 1) +
301 	     xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK), blksz) +
302 	     xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
303 	     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
304 
305 	if (xfs_has_realtime(mp)) {
306 		t2 = xfs_calc_inode_res(mp, 1) +
307 		     xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK),
308 				     blksz) +
309 		     xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
310 		     xfs_calc_buf_res(xfs_rtalloc_block_count(mp, 1), blksz) +
311 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1), blksz);
312 	} else {
313 		t2 = 0;
314 	}
315 
316 	t3 = xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
317 	     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
318 
319 	/*
320 	 * In the early days of reflink, we included enough reservation to log
321 	 * two refcountbt splits for each transaction.  The codebase runs
322 	 * refcountbt updates in separate transactions now, so to compute the
323 	 * minimum log size, add the refcountbtree splits back to t1 and t3 and
324 	 * do not account them separately as t4.  Reflink did not support
325 	 * realtime when the reservations were established, so no adjustment to
326 	 * t2 is needed.
327 	 */
328 	if (for_minlogsize) {
329 		unsigned int	adj = 0;
330 
331 		if (xfs_has_reflink(mp))
332 			adj = xfs_calc_buf_res(
333 					xfs_refcountbt_block_count(mp, 2),
334 					blksz);
335 		t1 += adj;
336 		t3 += adj;
337 		return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
338 	}
339 
340 	t4 = xfs_calc_refcountbt_reservation(mp, 1);
341 	return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
342 }
343 
344 unsigned int
345 xfs_calc_write_reservation_minlogsize(
346 	struct xfs_mount	*mp)
347 {
348 	return xfs_calc_write_reservation(mp, true);
349 }
350 
351 /*
352  * In truncating a file we free up to two extents at once.  We can modify (t1):
353  *    the inode being truncated: inode size
354  *    the inode's bmap btree: (max depth + 1) * block size
355  * And the bmap_finish transaction can free the blocks and bmap blocks (t2):
356  *    the agf for each of the ags: 4 * sector size
357  *    the agfl for each of the ags: 4 * sector size
358  *    the super block to reflect the freed blocks: sector size
359  *    worst case split in allocation btrees per extent assuming 4 extents:
360  *		4 exts * 2 trees * (2 * max depth - 1) * block size
361  * Or, if it's a realtime file (t3):
362  *    the agf for each of the ags: 2 * sector size
363  *    the agfl for each of the ags: 2 * sector size
364  *    the super block to reflect the freed blocks: sector size
365  *    the realtime bitmap:
366  *		2 exts * ((XFS_BMBT_MAX_EXTLEN / rtextsize) / NBBY) bytes
367  *    the realtime summary: 2 exts * 1 block
368  *    worst case split in allocation btrees per extent assuming 2 extents:
369  *		2 exts * 2 trees * (2 * max depth - 1) * block size
370  * And any refcount updates that happen in a separate transaction (t4).
371  */
372 STATIC uint
373 xfs_calc_itruncate_reservation(
374 	struct xfs_mount	*mp,
375 	bool			for_minlogsize)
376 {
377 	unsigned int		t1, t2, t3, t4;
378 	unsigned int		blksz = XFS_FSB_TO_B(mp, 1);
379 
380 	t1 = xfs_calc_inode_res(mp, 1) +
381 	     xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) + 1, blksz);
382 
383 	t2 = xfs_calc_buf_res(9, mp->m_sb.sb_sectsize) +
384 	     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 4), blksz);
385 
386 	if (xfs_has_realtime(mp)) {
387 		t3 = xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
388 		     xfs_calc_buf_res(xfs_rtalloc_block_count(mp, 2), blksz) +
389 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2), blksz);
390 	} else {
391 		t3 = 0;
392 	}
393 
394 	/*
395 	 * In the early days of reflink, we included enough reservation to log
396 	 * four refcountbt splits in the same transaction as bnobt/cntbt
397 	 * updates.  The codebase runs refcountbt updates in separate
398 	 * transactions now, so to compute the minimum log size, add the
399 	 * refcount btree splits back here and do not compute them separately
400 	 * as t4.  Reflink did not support realtime when the reservations were
401 	 * established, so do not adjust t3.
402 	 */
403 	if (for_minlogsize) {
404 		if (xfs_has_reflink(mp))
405 			t2 += xfs_calc_buf_res(
406 					xfs_refcountbt_block_count(mp, 4),
407 					blksz);
408 
409 		return XFS_DQUOT_LOGRES(mp) + max3(t1, t2, t3);
410 	}
411 
412 	t4 = xfs_calc_refcountbt_reservation(mp, 2);
413 	return XFS_DQUOT_LOGRES(mp) + max(t4, max3(t1, t2, t3));
414 }
415 
416 unsigned int
417 xfs_calc_itruncate_reservation_minlogsize(
418 	struct xfs_mount	*mp)
419 {
420 	return xfs_calc_itruncate_reservation(mp, true);
421 }
422 
423 /*
424  * In renaming a files we can modify:
425  *    the five inodes involved: 5 * inode size
426  *    the two directory btrees: 2 * (max depth + v2) * dir block size
427  *    the two directory bmap btrees: 2 * max depth * block size
428  * And the bmap_finish transaction can free dir and bmap blocks (two sets
429  *	of bmap blocks) giving:
430  *    the agf for the ags in which the blocks live: 3 * sector size
431  *    the agfl for the ags in which the blocks live: 3 * sector size
432  *    the superblock for the free block count: sector size
433  *    the allocation btrees: 3 exts * 2 trees * (2 * max depth - 1) * block size
434  */
435 STATIC uint
436 xfs_calc_rename_reservation(
437 	struct xfs_mount	*mp)
438 {
439 	return XFS_DQUOT_LOGRES(mp) +
440 		max((xfs_calc_inode_res(mp, 5) +
441 		     xfs_calc_buf_res(2 * XFS_DIROP_LOG_COUNT(mp),
442 				      XFS_FSB_TO_B(mp, 1))),
443 		    (xfs_calc_buf_res(7, mp->m_sb.sb_sectsize) +
444 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 3),
445 				      XFS_FSB_TO_B(mp, 1))));
446 }
447 
448 /*
449  * For removing an inode from unlinked list at first, we can modify:
450  *    the agi hash list and counters: sector size
451  *    the on disk inode before ours in the agi hash list: inode cluster size
452  *    the on disk inode in the agi hash list: inode cluster size
453  */
454 STATIC uint
455 xfs_calc_iunlink_remove_reservation(
456 	struct xfs_mount        *mp)
457 {
458 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
459 	       2 * M_IGEO(mp)->inode_cluster_size;
460 }
461 
462 /*
463  * For creating a link to an inode:
464  *    the parent directory inode: inode size
465  *    the linked inode: inode size
466  *    the directory btree could split: (max depth + v2) * dir block size
467  *    the directory bmap btree could join or split: (max depth + v2) * blocksize
468  * And the bmap_finish transaction can free some bmap blocks giving:
469  *    the agf for the ag in which the blocks live: sector size
470  *    the agfl for the ag in which the blocks live: sector size
471  *    the superblock for the free block count: sector size
472  *    the allocation btrees: 2 trees * (2 * max depth - 1) * block size
473  */
474 STATIC uint
475 xfs_calc_link_reservation(
476 	struct xfs_mount	*mp)
477 {
478 	return XFS_DQUOT_LOGRES(mp) +
479 		xfs_calc_iunlink_remove_reservation(mp) +
480 		max((xfs_calc_inode_res(mp, 2) +
481 		     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
482 				      XFS_FSB_TO_B(mp, 1))),
483 		    (xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
484 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
485 				      XFS_FSB_TO_B(mp, 1))));
486 }
487 
488 /*
489  * For adding an inode to unlinked list we can modify:
490  *    the agi hash list: sector size
491  *    the on disk inode: inode cluster size
492  */
493 STATIC uint
494 xfs_calc_iunlink_add_reservation(xfs_mount_t *mp)
495 {
496 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
497 			M_IGEO(mp)->inode_cluster_size;
498 }
499 
500 /*
501  * For removing a directory entry we can modify:
502  *    the parent directory inode: inode size
503  *    the removed inode: inode size
504  *    the directory btree could join: (max depth + v2) * dir block size
505  *    the directory bmap btree could join or split: (max depth + v2) * blocksize
506  * And the bmap_finish transaction can free the dir and bmap blocks giving:
507  *    the agf for the ag in which the blocks live: 2 * sector size
508  *    the agfl for the ag in which the blocks live: 2 * sector size
509  *    the superblock for the free block count: sector size
510  *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
511  */
512 STATIC uint
513 xfs_calc_remove_reservation(
514 	struct xfs_mount	*mp)
515 {
516 	return XFS_DQUOT_LOGRES(mp) +
517 		xfs_calc_iunlink_add_reservation(mp) +
518 		max((xfs_calc_inode_res(mp, 2) +
519 		     xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp),
520 				      XFS_FSB_TO_B(mp, 1))),
521 		    (xfs_calc_buf_res(4, mp->m_sb.sb_sectsize) +
522 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2),
523 				      XFS_FSB_TO_B(mp, 1))));
524 }
525 
526 /*
527  * For create, break it in to the two cases that the transaction
528  * covers. We start with the modify case - allocation done by modification
529  * of the state of existing inodes - and the allocation case.
530  */
531 
532 /*
533  * For create we can modify:
534  *    the parent directory inode: inode size
535  *    the new inode: inode size
536  *    the inode btree entry: block size
537  *    the superblock for the nlink flag: sector size
538  *    the directory btree: (max depth + v2) * dir block size
539  *    the directory inode's bmap btree: (max depth + v2) * block size
540  *    the finobt (record modification and allocation btrees)
541  */
542 STATIC uint
543 xfs_calc_create_resv_modify(
544 	struct xfs_mount	*mp)
545 {
546 	return xfs_calc_inode_res(mp, 2) +
547 		xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
548 		(uint)XFS_FSB_TO_B(mp, 1) +
549 		xfs_calc_buf_res(XFS_DIROP_LOG_COUNT(mp), XFS_FSB_TO_B(mp, 1)) +
550 		xfs_calc_finobt_res(mp);
551 }
552 
553 /*
554  * For icreate we can allocate some inodes giving:
555  *    the agi and agf of the ag getting the new inodes: 2 * sectorsize
556  *    the superblock for the nlink flag: sector size
557  *    the inode chunk (allocation, optional init)
558  *    the inobt (record insertion)
559  *    the finobt (optional, record insertion)
560  */
561 STATIC uint
562 xfs_calc_icreate_resv_alloc(
563 	struct xfs_mount	*mp)
564 {
565 	return xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
566 		mp->m_sb.sb_sectsize +
567 		xfs_calc_inode_chunk_res(mp, _ALLOC) +
568 		xfs_calc_inobt_res(mp) +
569 		xfs_calc_finobt_res(mp);
570 }
571 
572 STATIC uint
573 xfs_calc_icreate_reservation(xfs_mount_t *mp)
574 {
575 	return XFS_DQUOT_LOGRES(mp) +
576 		max(xfs_calc_icreate_resv_alloc(mp),
577 		    xfs_calc_create_resv_modify(mp));
578 }
579 
580 STATIC uint
581 xfs_calc_create_tmpfile_reservation(
582 	struct xfs_mount        *mp)
583 {
584 	uint	res = XFS_DQUOT_LOGRES(mp);
585 
586 	res += xfs_calc_icreate_resv_alloc(mp);
587 	return res + xfs_calc_iunlink_add_reservation(mp);
588 }
589 
590 /*
591  * Making a new directory is the same as creating a new file.
592  */
593 STATIC uint
594 xfs_calc_mkdir_reservation(
595 	struct xfs_mount	*mp)
596 {
597 	return xfs_calc_icreate_reservation(mp);
598 }
599 
600 
601 /*
602  * Making a new symplink is the same as creating a new file, but
603  * with the added blocks for remote symlink data which can be up to 1kB in
604  * length (XFS_SYMLINK_MAXLEN).
605  */
606 STATIC uint
607 xfs_calc_symlink_reservation(
608 	struct xfs_mount	*mp)
609 {
610 	return xfs_calc_icreate_reservation(mp) +
611 	       xfs_calc_buf_res(1, XFS_SYMLINK_MAXLEN);
612 }
613 
614 /*
615  * In freeing an inode we can modify:
616  *    the inode being freed: inode size
617  *    the super block free inode counter, AGF and AGFL: sector size
618  *    the on disk inode (agi unlinked list removal)
619  *    the inode chunk (invalidated, headers only)
620  *    the inode btree
621  *    the finobt (record insertion, removal or modification)
622  *
623  * Note that the inode chunk res. includes an allocfree res. for freeing of the
624  * inode chunk. This is technically extraneous because the inode chunk free is
625  * deferred (it occurs after a transaction roll). Include the extra reservation
626  * anyways since we've had reports of ifree transaction overruns due to too many
627  * agfl fixups during inode chunk frees.
628  */
629 STATIC uint
630 xfs_calc_ifree_reservation(
631 	struct xfs_mount	*mp)
632 {
633 	return XFS_DQUOT_LOGRES(mp) +
634 		xfs_calc_inode_res(mp, 1) +
635 		xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
636 		xfs_calc_iunlink_remove_reservation(mp) +
637 		xfs_calc_inode_chunk_res(mp, _FREE) +
638 		xfs_calc_inobt_res(mp) +
639 		xfs_calc_finobt_res(mp);
640 }
641 
642 /*
643  * When only changing the inode we log the inode and possibly the superblock
644  * We also add a bit of slop for the transaction stuff.
645  */
646 STATIC uint
647 xfs_calc_ichange_reservation(
648 	struct xfs_mount	*mp)
649 {
650 	return XFS_DQUOT_LOGRES(mp) +
651 		xfs_calc_inode_res(mp, 1) +
652 		xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
653 
654 }
655 
656 /*
657  * Growing the data section of the filesystem.
658  *	superblock
659  *	agi and agf
660  *	allocation btrees
661  */
662 STATIC uint
663 xfs_calc_growdata_reservation(
664 	struct xfs_mount	*mp)
665 {
666 	return xfs_calc_buf_res(3, mp->m_sb.sb_sectsize) +
667 		xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
668 				 XFS_FSB_TO_B(mp, 1));
669 }
670 
671 /*
672  * Growing the rt section of the filesystem.
673  * In the first set of transactions (ALLOC) we allocate space to the
674  * bitmap or summary files.
675  *	superblock: sector size
676  *	agf of the ag from which the extent is allocated: sector size
677  *	bmap btree for bitmap/summary inode: max depth * blocksize
678  *	bitmap/summary inode: inode size
679  *	allocation btrees for 1 block alloc: 2 * (2 * maxdepth - 1) * blocksize
680  */
681 STATIC uint
682 xfs_calc_growrtalloc_reservation(
683 	struct xfs_mount	*mp)
684 {
685 	return xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
686 		xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK),
687 				 XFS_FSB_TO_B(mp, 1)) +
688 		xfs_calc_inode_res(mp, 1) +
689 		xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
690 				 XFS_FSB_TO_B(mp, 1));
691 }
692 
693 /*
694  * Growing the rt section of the filesystem.
695  * In the second set of transactions (ZERO) we zero the new metadata blocks.
696  *	one bitmap/summary block: blocksize
697  */
698 STATIC uint
699 xfs_calc_growrtzero_reservation(
700 	struct xfs_mount	*mp)
701 {
702 	return xfs_calc_buf_res(1, mp->m_sb.sb_blocksize);
703 }
704 
705 /*
706  * Growing the rt section of the filesystem.
707  * In the third set of transactions (FREE) we update metadata without
708  * allocating any new blocks.
709  *	superblock: sector size
710  *	bitmap inode: inode size
711  *	summary inode: inode size
712  *	one bitmap block: blocksize
713  *	summary blocks: new summary size
714  */
715 STATIC uint
716 xfs_calc_growrtfree_reservation(
717 	struct xfs_mount	*mp)
718 {
719 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
720 		xfs_calc_inode_res(mp, 2) +
721 		xfs_calc_buf_res(1, mp->m_sb.sb_blocksize) +
722 		xfs_calc_buf_res(1, mp->m_rsumsize);
723 }
724 
725 /*
726  * Logging the inode modification timestamp on a synchronous write.
727  *	inode
728  */
729 STATIC uint
730 xfs_calc_swrite_reservation(
731 	struct xfs_mount	*mp)
732 {
733 	return xfs_calc_inode_res(mp, 1);
734 }
735 
736 /*
737  * Logging the inode mode bits when writing a setuid/setgid file
738  *	inode
739  */
740 STATIC uint
741 xfs_calc_writeid_reservation(
742 	struct xfs_mount	*mp)
743 {
744 	return xfs_calc_inode_res(mp, 1);
745 }
746 
747 /*
748  * Converting the inode from non-attributed to attributed.
749  *	the inode being converted: inode size
750  *	agf block and superblock (for block allocation)
751  *	the new block (directory sized)
752  *	bmap blocks for the new directory block
753  *	allocation btrees
754  */
755 STATIC uint
756 xfs_calc_addafork_reservation(
757 	struct xfs_mount	*mp)
758 {
759 	return XFS_DQUOT_LOGRES(mp) +
760 		xfs_calc_inode_res(mp, 1) +
761 		xfs_calc_buf_res(2, mp->m_sb.sb_sectsize) +
762 		xfs_calc_buf_res(1, mp->m_dir_geo->blksize) +
763 		xfs_calc_buf_res(XFS_DAENTER_BMAP1B(mp, XFS_DATA_FORK) + 1,
764 				 XFS_FSB_TO_B(mp, 1)) +
765 		xfs_calc_buf_res(xfs_allocfree_block_count(mp, 1),
766 				 XFS_FSB_TO_B(mp, 1));
767 }
768 
769 /*
770  * Removing the attribute fork of a file
771  *    the inode being truncated: inode size
772  *    the inode's bmap btree: max depth * block size
773  * And the bmap_finish transaction can free the blocks and bmap blocks:
774  *    the agf for each of the ags: 4 * sector size
775  *    the agfl for each of the ags: 4 * sector size
776  *    the super block to reflect the freed blocks: sector size
777  *    worst case split in allocation btrees per extent assuming 4 extents:
778  *		4 exts * 2 trees * (2 * max depth - 1) * block size
779  */
780 STATIC uint
781 xfs_calc_attrinval_reservation(
782 	struct xfs_mount	*mp)
783 {
784 	return max((xfs_calc_inode_res(mp, 1) +
785 		    xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK),
786 				     XFS_FSB_TO_B(mp, 1))),
787 		   (xfs_calc_buf_res(9, mp->m_sb.sb_sectsize) +
788 		    xfs_calc_buf_res(xfs_allocfree_block_count(mp, 4),
789 				     XFS_FSB_TO_B(mp, 1))));
790 }
791 
792 /*
793  * Setting an attribute at mount time.
794  *	the inode getting the attribute
795  *	the superblock for allocations
796  *	the agfs extents are allocated from
797  *	the attribute btree * max depth
798  *	the inode allocation btree
799  * Since attribute transaction space is dependent on the size of the attribute,
800  * the calculation is done partially at mount time and partially at runtime(see
801  * below).
802  */
803 STATIC uint
804 xfs_calc_attrsetm_reservation(
805 	struct xfs_mount	*mp)
806 {
807 	return XFS_DQUOT_LOGRES(mp) +
808 		xfs_calc_inode_res(mp, 1) +
809 		xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
810 		xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH, XFS_FSB_TO_B(mp, 1));
811 }
812 
813 /*
814  * Setting an attribute at runtime, transaction space unit per block.
815  * 	the superblock for allocations: sector size
816  *	the inode bmap btree could join or split: max depth * block size
817  * Since the runtime attribute transaction space is dependent on the total
818  * blocks needed for the 1st bmap, here we calculate out the space unit for
819  * one block so that the caller could figure out the total space according
820  * to the attibute extent length in blocks by:
821  *	ext * M_RES(mp)->tr_attrsetrt.tr_logres
822  */
823 STATIC uint
824 xfs_calc_attrsetrt_reservation(
825 	struct xfs_mount	*mp)
826 {
827 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize) +
828 		xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK),
829 				 XFS_FSB_TO_B(mp, 1));
830 }
831 
832 /*
833  * Removing an attribute.
834  *    the inode: inode size
835  *    the attribute btree could join: max depth * block size
836  *    the inode bmap btree could join or split: max depth * block size
837  * And the bmap_finish transaction can free the attr blocks freed giving:
838  *    the agf for the ag in which the blocks live: 2 * sector size
839  *    the agfl for the ag in which the blocks live: 2 * sector size
840  *    the superblock for the free block count: sector size
841  *    the allocation btrees: 2 exts * 2 trees * (2 * max depth - 1) * block size
842  */
843 STATIC uint
844 xfs_calc_attrrm_reservation(
845 	struct xfs_mount	*mp)
846 {
847 	return XFS_DQUOT_LOGRES(mp) +
848 		max((xfs_calc_inode_res(mp, 1) +
849 		     xfs_calc_buf_res(XFS_DA_NODE_MAXDEPTH,
850 				      XFS_FSB_TO_B(mp, 1)) +
851 		     (uint)XFS_FSB_TO_B(mp,
852 					XFS_BM_MAXLEVELS(mp, XFS_ATTR_FORK)) +
853 		     xfs_calc_buf_res(XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK), 0)),
854 		    (xfs_calc_buf_res(5, mp->m_sb.sb_sectsize) +
855 		     xfs_calc_buf_res(xfs_allocfree_block_count(mp, 2),
856 				      XFS_FSB_TO_B(mp, 1))));
857 }
858 
859 /*
860  * Clearing a bad agino number in an agi hash bucket.
861  */
862 STATIC uint
863 xfs_calc_clear_agi_bucket_reservation(
864 	struct xfs_mount	*mp)
865 {
866 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
867 }
868 
869 /*
870  * Adjusting quota limits.
871  *    the disk quota buffer: sizeof(struct xfs_disk_dquot)
872  */
873 STATIC uint
874 xfs_calc_qm_setqlim_reservation(void)
875 {
876 	return xfs_calc_buf_res(1, sizeof(struct xfs_disk_dquot));
877 }
878 
879 /*
880  * Allocating quota on disk if needed.
881  *	the write transaction log space for quota file extent allocation
882  *	the unit of quota allocation: one system block size
883  */
884 STATIC uint
885 xfs_calc_qm_dqalloc_reservation(
886 	struct xfs_mount	*mp,
887 	bool			for_minlogsize)
888 {
889 	return xfs_calc_write_reservation(mp, for_minlogsize) +
890 		xfs_calc_buf_res(1,
891 			XFS_FSB_TO_B(mp, XFS_DQUOT_CLUSTER_SIZE_FSB) - 1);
892 }
893 
894 unsigned int
895 xfs_calc_qm_dqalloc_reservation_minlogsize(
896 	struct xfs_mount	*mp)
897 {
898 	return xfs_calc_qm_dqalloc_reservation(mp, true);
899 }
900 
901 /*
902  * Syncing the incore super block changes to disk.
903  *     the super block to reflect the changes: sector size
904  */
905 STATIC uint
906 xfs_calc_sb_reservation(
907 	struct xfs_mount	*mp)
908 {
909 	return xfs_calc_buf_res(1, mp->m_sb.sb_sectsize);
910 }
911 
912 void
913 xfs_trans_resv_calc(
914 	struct xfs_mount	*mp,
915 	struct xfs_trans_resv	*resp)
916 {
917 	int			logcount_adj = 0;
918 
919 	/*
920 	 * The following transactions are logged in physical format and
921 	 * require a permanent reservation on space.
922 	 */
923 	resp->tr_write.tr_logres = xfs_calc_write_reservation(mp, false);
924 	resp->tr_write.tr_logcount = XFS_WRITE_LOG_COUNT;
925 	resp->tr_write.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
926 
927 	resp->tr_itruncate.tr_logres = xfs_calc_itruncate_reservation(mp, false);
928 	resp->tr_itruncate.tr_logcount = XFS_ITRUNCATE_LOG_COUNT;
929 	resp->tr_itruncate.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
930 
931 	resp->tr_rename.tr_logres = xfs_calc_rename_reservation(mp);
932 	resp->tr_rename.tr_logcount = XFS_RENAME_LOG_COUNT;
933 	resp->tr_rename.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
934 
935 	resp->tr_link.tr_logres = xfs_calc_link_reservation(mp);
936 	resp->tr_link.tr_logcount = XFS_LINK_LOG_COUNT;
937 	resp->tr_link.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
938 
939 	resp->tr_remove.tr_logres = xfs_calc_remove_reservation(mp);
940 	resp->tr_remove.tr_logcount = XFS_REMOVE_LOG_COUNT;
941 	resp->tr_remove.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
942 
943 	resp->tr_symlink.tr_logres = xfs_calc_symlink_reservation(mp);
944 	resp->tr_symlink.tr_logcount = XFS_SYMLINK_LOG_COUNT;
945 	resp->tr_symlink.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
946 
947 	resp->tr_create.tr_logres = xfs_calc_icreate_reservation(mp);
948 	resp->tr_create.tr_logcount = XFS_CREATE_LOG_COUNT;
949 	resp->tr_create.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
950 
951 	resp->tr_create_tmpfile.tr_logres =
952 			xfs_calc_create_tmpfile_reservation(mp);
953 	resp->tr_create_tmpfile.tr_logcount = XFS_CREATE_TMPFILE_LOG_COUNT;
954 	resp->tr_create_tmpfile.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
955 
956 	resp->tr_mkdir.tr_logres = xfs_calc_mkdir_reservation(mp);
957 	resp->tr_mkdir.tr_logcount = XFS_MKDIR_LOG_COUNT;
958 	resp->tr_mkdir.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
959 
960 	resp->tr_ifree.tr_logres = xfs_calc_ifree_reservation(mp);
961 	resp->tr_ifree.tr_logcount = XFS_INACTIVE_LOG_COUNT;
962 	resp->tr_ifree.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
963 
964 	resp->tr_addafork.tr_logres = xfs_calc_addafork_reservation(mp);
965 	resp->tr_addafork.tr_logcount = XFS_ADDAFORK_LOG_COUNT;
966 	resp->tr_addafork.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
967 
968 	resp->tr_attrinval.tr_logres = xfs_calc_attrinval_reservation(mp);
969 	resp->tr_attrinval.tr_logcount = XFS_ATTRINVAL_LOG_COUNT;
970 	resp->tr_attrinval.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
971 
972 	resp->tr_attrsetm.tr_logres = xfs_calc_attrsetm_reservation(mp);
973 	resp->tr_attrsetm.tr_logcount = XFS_ATTRSET_LOG_COUNT;
974 	resp->tr_attrsetm.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
975 
976 	resp->tr_attrrm.tr_logres = xfs_calc_attrrm_reservation(mp);
977 	resp->tr_attrrm.tr_logcount = XFS_ATTRRM_LOG_COUNT;
978 	resp->tr_attrrm.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
979 
980 	resp->tr_growrtalloc.tr_logres = xfs_calc_growrtalloc_reservation(mp);
981 	resp->tr_growrtalloc.tr_logcount = XFS_DEFAULT_PERM_LOG_COUNT;
982 	resp->tr_growrtalloc.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
983 
984 	resp->tr_qm_dqalloc.tr_logres = xfs_calc_qm_dqalloc_reservation(mp,
985 			false);
986 	resp->tr_qm_dqalloc.tr_logcount = XFS_WRITE_LOG_COUNT;
987 	resp->tr_qm_dqalloc.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
988 
989 	/*
990 	 * The following transactions are logged in logical format with
991 	 * a default log count.
992 	 */
993 	resp->tr_qm_setqlim.tr_logres = xfs_calc_qm_setqlim_reservation();
994 	resp->tr_qm_setqlim.tr_logcount = XFS_DEFAULT_LOG_COUNT;
995 
996 	resp->tr_sb.tr_logres = xfs_calc_sb_reservation(mp);
997 	resp->tr_sb.tr_logcount = XFS_DEFAULT_LOG_COUNT;
998 
999 	/* growdata requires permanent res; it can free space to the last AG */
1000 	resp->tr_growdata.tr_logres = xfs_calc_growdata_reservation(mp);
1001 	resp->tr_growdata.tr_logcount = XFS_DEFAULT_PERM_LOG_COUNT;
1002 	resp->tr_growdata.tr_logflags |= XFS_TRANS_PERM_LOG_RES;
1003 
1004 	/* The following transaction are logged in logical format */
1005 	resp->tr_ichange.tr_logres = xfs_calc_ichange_reservation(mp);
1006 	resp->tr_fsyncts.tr_logres = xfs_calc_swrite_reservation(mp);
1007 	resp->tr_writeid.tr_logres = xfs_calc_writeid_reservation(mp);
1008 	resp->tr_attrsetrt.tr_logres = xfs_calc_attrsetrt_reservation(mp);
1009 	resp->tr_clearagi.tr_logres = xfs_calc_clear_agi_bucket_reservation(mp);
1010 	resp->tr_growrtzero.tr_logres = xfs_calc_growrtzero_reservation(mp);
1011 	resp->tr_growrtfree.tr_logres = xfs_calc_growrtfree_reservation(mp);
1012 
1013 	/*
1014 	 * Add one logcount for BUI items that appear with rmap or reflink,
1015 	 * one logcount for refcount intent items, and one logcount for rmap
1016 	 * intent items.
1017 	 */
1018 	if (xfs_has_reflink(mp) || xfs_has_rmapbt(mp))
1019 		logcount_adj++;
1020 	if (xfs_has_reflink(mp))
1021 		logcount_adj++;
1022 	if (xfs_has_rmapbt(mp))
1023 		logcount_adj++;
1024 
1025 	resp->tr_itruncate.tr_logcount += logcount_adj;
1026 	resp->tr_write.tr_logcount += logcount_adj;
1027 	resp->tr_qm_dqalloc.tr_logcount += logcount_adj;
1028 }
1029