1 // SPDX-License-Identifier: GPL-2.0
2
3 #include "ctree.h"
4 #include "delalloc-space.h"
5 #include "block-rsv.h"
6 #include "btrfs_inode.h"
7 #include "space-info.h"
8 #include "transaction.h"
9 #include "qgroup.h"
10 #include "block-group.h"
11
12 int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
13 {
14 struct btrfs_root *root = inode->root;
15 struct btrfs_fs_info *fs_info = root->fs_info;
16 struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
17 u64 used;
18 int ret = 0;
19 int need_commit = 2;
20 int have_pinned_space;
21
22 /* Make sure bytes are sectorsize aligned */
23 bytes = ALIGN(bytes, fs_info->sectorsize);
24
25 if (btrfs_is_free_space_inode(inode)) {
26 need_commit = 0;
27 ASSERT(current->journal_info);
28 }
29
30 again:
31 /* Make sure we have enough space to handle the data first */
32 spin_lock(&data_sinfo->lock);
33 used = btrfs_space_info_used(data_sinfo, true);
34
35 if (used + bytes > data_sinfo->total_bytes) {
36 struct btrfs_trans_handle *trans;
37
38 /*
39 * If we don't have enough free bytes in this space then we need
40 * to alloc a new chunk.
41 */
42 if (!data_sinfo->full) {
43 u64 alloc_target;
44
45 data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
46 spin_unlock(&data_sinfo->lock);
47
48 alloc_target = btrfs_data_alloc_profile(fs_info);
49 /*
50 * It is ugly that we don't call nolock join
51 * transaction for the free space inode case here.
52 * But it is safe because we only do the data space
53 * reservation for the free space cache in the
54 * transaction context, the common join transaction
55 * just increase the counter of the current transaction
56 * handler, doesn't try to acquire the trans_lock of
57 * the fs.
58 */
59 trans = btrfs_join_transaction(root);
60 if (IS_ERR(trans))
61 return PTR_ERR(trans);
62
63 ret = btrfs_chunk_alloc(trans, alloc_target,
64 CHUNK_ALLOC_NO_FORCE);
65 btrfs_end_transaction(trans);
66 if (ret < 0) {
67 if (ret != -ENOSPC)
68 return ret;
69 else {
70 have_pinned_space = 1;
71 goto commit_trans;
72 }
73 }
74
75 goto again;
76 }
77
78 /*
79 * If we don't have enough pinned space to deal with this
80 * allocation, and no removed chunk in current transaction,
81 * don't bother committing the transaction.
82 */
83 have_pinned_space = __percpu_counter_compare(
84 &data_sinfo->total_bytes_pinned,
85 used + bytes - data_sinfo->total_bytes,
86 BTRFS_TOTAL_BYTES_PINNED_BATCH);
87 spin_unlock(&data_sinfo->lock);
88
89 /* Commit the current transaction and try again */
90 commit_trans:
91 if (need_commit) {
92 need_commit--;
93
94 if (need_commit > 0) {
95 btrfs_start_delalloc_roots(fs_info, -1);
96 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
97 (u64)-1);
98 }
99
100 trans = btrfs_join_transaction(root);
101 if (IS_ERR(trans))
102 return PTR_ERR(trans);
103 if (have_pinned_space >= 0 ||
104 test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
105 &trans->transaction->flags) ||
106 need_commit > 0) {
107 ret = btrfs_commit_transaction(trans);
108 if (ret)
109 return ret;
110 /*
111 * The cleaner kthread might still be doing iput
112 * operations. Wait for it to finish so that
113 * more space is released. We don't need to
114 * explicitly run the delayed iputs here because
115 * the commit_transaction would have woken up
116 * the cleaner.
117 */
118 ret = btrfs_wait_on_delayed_iputs(fs_info);
119 if (ret)
120 return ret;
121 goto again;
122 } else {
123 btrfs_end_transaction(trans);
124 }
125 }
126
127 trace_btrfs_space_reservation(fs_info,
128 "space_info:enospc",
129 data_sinfo->flags, bytes, 1);
130 return -ENOSPC;
131 }
132 btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, bytes);
133 spin_unlock(&data_sinfo->lock);
134
135 return 0;
136 }
137
138 int btrfs_check_data_free_space(struct inode *inode,
139 struct extent_changeset **reserved, u64 start, u64 len)
140 {
141 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
142 int ret;
143
144 /* align the range */
145 len = round_up(start + len, fs_info->sectorsize) -
146 round_down(start, fs_info->sectorsize);
147 start = round_down(start, fs_info->sectorsize);
148
149 ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
150 if (ret < 0)
151 return ret;
152
153 /* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
154 ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
155 if (ret < 0)
156 btrfs_free_reserved_data_space_noquota(inode, start, len);
157 else
158 ret = 0;
159 return ret;
160 }
161
162 /*
163 * Called if we need to clear a data reservation for this inode
164 * Normally in a error case.
165 *
166 * This one will *NOT* use accurate qgroup reserved space API, just for case
167 * which we can't sleep and is sure it won't affect qgroup reserved space.
168 * Like clear_bit_hook().
169 */
170 void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
171 u64 len)
172 {
173 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
174 struct btrfs_space_info *data_sinfo;
175
176 /* Make sure the range is aligned to sectorsize */
177 len = round_up(start + len, fs_info->sectorsize) -
178 round_down(start, fs_info->sectorsize);
179 start = round_down(start, fs_info->sectorsize);
180
181 data_sinfo = fs_info->data_sinfo;
182 spin_lock(&data_sinfo->lock);
183 btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, -len);
184 spin_unlock(&data_sinfo->lock);
185 }
186
187 /*
188 * Called if we need to clear a data reservation for this inode
189 * Normally in a error case.
190 *
191 * This one will handle the per-inode data rsv map for accurate reserved
192 * space framework.
193 */
194 void btrfs_free_reserved_data_space(struct inode *inode,
195 struct extent_changeset *reserved, u64 start, u64 len)
196 {
197 struct btrfs_root *root = BTRFS_I(inode)->root;
198
199 /* Make sure the range is aligned to sectorsize */
200 len = round_up(start + len, root->fs_info->sectorsize) -
201 round_down(start, root->fs_info->sectorsize);
202 start = round_down(start, root->fs_info->sectorsize);
203
204 btrfs_free_reserved_data_space_noquota(inode, start, len);
205 btrfs_qgroup_free_data(inode, reserved, start, len);
206 }
207
208 /**
209 * btrfs_inode_rsv_release - release any excessive reservation.
210 * @inode - the inode we need to release from.
211 * @qgroup_free - free or convert qgroup meta.
212 * Unlike normal operation, qgroup meta reservation needs to know if we are
213 * freeing qgroup reservation or just converting it into per-trans. Normally
214 * @qgroup_free is true for error handling, and false for normal release.
215 *
216 * This is the same as btrfs_block_rsv_release, except that it handles the
217 * tracepoint for the reservation.
218 */
219 static void btrfs_inode_rsv_release(struct btrfs_inode *inode, bool qgroup_free)
220 {
221 struct btrfs_fs_info *fs_info = inode->root->fs_info;
222 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
223 u64 released = 0;
224 u64 qgroup_to_release = 0;
225
226 /*
227 * Since we statically set the block_rsv->size we just want to say we
228 * are releasing 0 bytes, and then we'll just get the reservation over
229 * the size free'd.
230 */
231 released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
232 &qgroup_to_release);
233 if (released > 0)
234 trace_btrfs_space_reservation(fs_info, "delalloc",
235 btrfs_ino(inode), released, 0);
236 if (qgroup_free)
237 btrfs_qgroup_free_meta_prealloc(inode->root, qgroup_to_release);
238 else
239 btrfs_qgroup_convert_reserved_meta(inode->root,
240 qgroup_to_release);
241 }
242
243 static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
244 struct btrfs_inode *inode)
245 {
246 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
247 u64 reserve_size = 0;
248 u64 qgroup_rsv_size = 0;
249 u64 csum_leaves;
250 unsigned outstanding_extents;
251
252 lockdep_assert_held(&inode->lock);
253 outstanding_extents = inode->outstanding_extents;
254
255 /*
256 * Insert size for the number of outstanding extents, 1 normal size for
257 * updating the inode.
258 */
259 if (outstanding_extents) {
260 reserve_size = btrfs_calc_insert_metadata_size(fs_info,
261 outstanding_extents);
262 reserve_size += btrfs_calc_metadata_size(fs_info, 1);
263 }
264 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info,
265 inode->csum_bytes);
266 reserve_size += btrfs_calc_insert_metadata_size(fs_info,
267 csum_leaves);
268 /*
269 * For qgroup rsv, the calculation is very simple:
270 * account one nodesize for each outstanding extent
271 *
272 * This is overestimating in most cases.
273 */
274 qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
275
276 spin_lock(&block_rsv->lock);
277 block_rsv->size = reserve_size;
278 block_rsv->qgroup_rsv_size = qgroup_rsv_size;
279 spin_unlock(&block_rsv->lock);
280 }
281
282 static void calc_inode_reservations(struct btrfs_fs_info *fs_info,
283 u64 num_bytes, u64 *meta_reserve,
284 u64 *qgroup_reserve)
285 {
286 u64 nr_extents = count_max_extents(num_bytes);
287 u64 csum_leaves = btrfs_csum_bytes_to_leaves(fs_info, num_bytes);
288 u64 inode_update = btrfs_calc_metadata_size(fs_info, 1);
289
290 *meta_reserve = btrfs_calc_insert_metadata_size(fs_info,
291 nr_extents + csum_leaves);
292
293 /*
294 * finish_ordered_io has to update the inode, so add the space required
295 * for an inode update.
296 */
297 *meta_reserve += inode_update;
298 *qgroup_reserve = nr_extents * fs_info->nodesize;
299 }
300
301 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes)
302 {
303 struct btrfs_root *root = inode->root;
304 struct btrfs_fs_info *fs_info = root->fs_info;
305 struct btrfs_block_rsv *block_rsv = &inode->block_rsv;
306 u64 meta_reserve, qgroup_reserve;
307 unsigned nr_extents;
308 enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
309 int ret = 0;
310 bool delalloc_lock = true;
311
312 /*
313 * If we are a free space inode we need to not flush since we will be in
314 * the middle of a transaction commit. We also don't need the delalloc
315 * mutex since we won't race with anybody. We need this mostly to make
316 * lockdep shut its filthy mouth.
317 *
318 * If we have a transaction open (can happen if we call truncate_block
319 * from truncate), then we need FLUSH_LIMIT so we don't deadlock.
320 */
321 if (btrfs_is_free_space_inode(inode)) {
322 flush = BTRFS_RESERVE_NO_FLUSH;
323 delalloc_lock = false;
324 } else {
325 if (current->journal_info)
326 flush = BTRFS_RESERVE_FLUSH_LIMIT;
327
328 if (btrfs_transaction_in_commit(fs_info))
329 schedule_timeout(1);
330 }
331
332 if (delalloc_lock)
333 mutex_lock(&inode->delalloc_mutex);
334
335 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
336
337 /*
338 * We always want to do it this way, every other way is wrong and ends
339 * in tears. Pre-reserving the amount we are going to add will always
340 * be the right way, because otherwise if we have enough parallelism we
341 * could end up with thousands of inodes all holding little bits of
342 * reservations they were able to make previously and the only way to
343 * reclaim that space is to ENOSPC out the operations and clear
344 * everything out and try again, which is bad. This way we just
345 * over-reserve slightly, and clean up the mess when we are done.
346 */
347 calc_inode_reservations(fs_info, num_bytes, &meta_reserve,
348 &qgroup_reserve);
349 ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
350 if (ret)
351 goto out_fail;
352 ret = btrfs_reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
353 if (ret)
354 goto out_qgroup;
355
356 /*
357 * Now we need to update our outstanding extents and csum bytes _first_
358 * and then add the reservation to the block_rsv. This keeps us from
359 * racing with an ordered completion or some such that would think it
360 * needs to free the reservation we just made.
361 */
362 spin_lock(&inode->lock);
363 nr_extents = count_max_extents(num_bytes);
364 btrfs_mod_outstanding_extents(inode, nr_extents);
365 inode->csum_bytes += num_bytes;
366 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
367 spin_unlock(&inode->lock);
368
369 /* Now we can safely add our space to our block rsv */
370 btrfs_block_rsv_add_bytes(block_rsv, meta_reserve, false);
371 trace_btrfs_space_reservation(root->fs_info, "delalloc",
372 btrfs_ino(inode), meta_reserve, 1);
373
374 spin_lock(&block_rsv->lock);
375 block_rsv->qgroup_rsv_reserved += qgroup_reserve;
376 spin_unlock(&block_rsv->lock);
377
378 if (delalloc_lock)
379 mutex_unlock(&inode->delalloc_mutex);
380 return 0;
381 out_qgroup:
382 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
383 out_fail:
384 if (delalloc_lock)
385 mutex_unlock(&inode->delalloc_mutex);
386 return ret;
387 }
388
389 /**
390 * btrfs_delalloc_release_metadata - release a metadata reservation for an inode
391 * @inode: the inode to release the reservation for.
392 * @num_bytes: the number of bytes we are releasing.
393 * @qgroup_free: free qgroup reservation or convert it to per-trans reservation
394 *
395 * This will release the metadata reservation for an inode. This can be called
396 * once we complete IO for a given set of bytes to release their metadata
397 * reservations, or on error for the same reason.
398 */
399 void btrfs_delalloc_release_metadata(struct btrfs_inode *inode, u64 num_bytes,
400 bool qgroup_free)
401 {
402 struct btrfs_fs_info *fs_info = inode->root->fs_info;
403
404 num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
405 spin_lock(&inode->lock);
406 inode->csum_bytes -= num_bytes;
407 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
408 spin_unlock(&inode->lock);
409
410 if (btrfs_is_testing(fs_info))
411 return;
412
413 btrfs_inode_rsv_release(inode, qgroup_free);
414 }
415
416 /**
417 * btrfs_delalloc_release_extents - release our outstanding_extents
418 * @inode: the inode to balance the reservation for.
419 * @num_bytes: the number of bytes we originally reserved with
420 *
421 * When we reserve space we increase outstanding_extents for the extents we may
422 * add. Once we've set the range as delalloc or created our ordered extents we
423 * have outstanding_extents to track the real usage, so we use this to free our
424 * temporarily tracked outstanding_extents. This _must_ be used in conjunction
425 * with btrfs_delalloc_reserve_metadata.
426 */
427 void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes)
428 {
429 struct btrfs_fs_info *fs_info = inode->root->fs_info;
430 unsigned num_extents;
431
432 spin_lock(&inode->lock);
433 num_extents = count_max_extents(num_bytes);
434 btrfs_mod_outstanding_extents(inode, -num_extents);
435 btrfs_calculate_inode_block_rsv_size(fs_info, inode);
436 spin_unlock(&inode->lock);
437
438 if (btrfs_is_testing(fs_info))
439 return;
440
441 btrfs_inode_rsv_release(inode, true);
442 }
443
444 /**
445 * btrfs_delalloc_reserve_space - reserve data and metadata space for
446 * delalloc
447 * @inode: inode we're writing to
448 * @start: start range we are writing to
449 * @len: how long the range we are writing to
450 * @reserved: mandatory parameter, record actually reserved qgroup ranges of
451 * current reservation.
452 *
453 * This will do the following things
454 *
455 * - reserve space in data space info for num bytes
456 * and reserve precious corresponding qgroup space
457 * (Done in check_data_free_space)
458 *
459 * - reserve space for metadata space, based on the number of outstanding
460 * extents and how much csums will be needed
461 * also reserve metadata space in a per root over-reserve method.
462 * - add to the inodes->delalloc_bytes
463 * - add it to the fs_info's delalloc inodes list.
464 * (Above 3 all done in delalloc_reserve_metadata)
465 *
466 * Return 0 for success
467 * Return <0 for error(-ENOSPC or -EQUOT)
468 */
469 int btrfs_delalloc_reserve_space(struct inode *inode,
470 struct extent_changeset **reserved, u64 start, u64 len)
471 {
472 int ret;
473
474 ret = btrfs_check_data_free_space(inode, reserved, start, len);
475 if (ret < 0)
476 return ret;
477 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
478 if (ret < 0)
479 btrfs_free_reserved_data_space(inode, *reserved, start, len);
480 return ret;
481 }
482
483 /**
484 * btrfs_delalloc_release_space - release data and metadata space for delalloc
485 * @inode: inode we're releasing space for
486 * @start: start position of the space already reserved
487 * @len: the len of the space already reserved
488 * @release_bytes: the len of the space we consumed or didn't use
489 *
490 * This function will release the metadata space that was not used and will
491 * decrement ->delalloc_bytes and remove it from the fs_info delalloc_inodes
492 * list if there are no delalloc bytes left.
493 * Also it will handle the qgroup reserved space.
494 */
495 void btrfs_delalloc_release_space(struct inode *inode,
496 struct extent_changeset *reserved,
497 u64 start, u64 len, bool qgroup_free)
498 {
499 btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
500 btrfs_free_reserved_data_space(inode, reserved, start, len);
501 }