1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright (c) 2000-2006 Silicon Graphics, Inc. |
4 | * Copyright (c) 2016-2018 Christoph Hellwig. |
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_inode.h" |
15 | #include "xfs_btree.h" |
16 | #include "xfs_bmap_btree.h" |
17 | #include "xfs_bmap.h" |
18 | #include "xfs_bmap_util.h" |
19 | #include "xfs_errortag.h" |
20 | #include "xfs_error.h" |
21 | #include "xfs_trans.h" |
22 | #include "xfs_trans_space.h" |
23 | #include "xfs_inode_item.h" |
24 | #include "xfs_iomap.h" |
25 | #include "xfs_trace.h" |
26 | #include "xfs_quota.h" |
27 | #include "xfs_dquot_item.h" |
28 | #include "xfs_dquot.h" |
29 | #include "xfs_reflink.h" |
30 | #include "xfs_health.h" |
31 | |
32 | #define XFS_ALLOC_ALIGN(mp, off) \ |
33 | (((off) >> mp->m_allocsize_log) << mp->m_allocsize_log) |
34 | |
35 | static int |
36 | xfs_alert_fsblock_zero( |
37 | xfs_inode_t *ip, |
38 | xfs_bmbt_irec_t *imap) |
39 | { |
40 | xfs_alert_tag(ip->i_mount, XFS_PTAG_FSBLOCK_ZERO, |
41 | "Access to block zero in inode %llu " |
42 | "start_block: %llx start_off: %llx " |
43 | "blkcnt: %llx extent-state: %x" , |
44 | (unsigned long long)ip->i_ino, |
45 | (unsigned long long)imap->br_startblock, |
46 | (unsigned long long)imap->br_startoff, |
47 | (unsigned long long)imap->br_blockcount, |
48 | imap->br_state); |
49 | xfs_bmap_mark_sick(ip, XFS_DATA_FORK); |
50 | return -EFSCORRUPTED; |
51 | } |
52 | |
53 | u64 |
54 | xfs_iomap_inode_sequence( |
55 | struct xfs_inode *ip, |
56 | u16 iomap_flags) |
57 | { |
58 | u64 cookie = 0; |
59 | |
60 | if (iomap_flags & IOMAP_F_XATTR) |
61 | return READ_ONCE(ip->i_af.if_seq); |
62 | if ((iomap_flags & IOMAP_F_SHARED) && ip->i_cowfp) |
63 | cookie = (u64)READ_ONCE(ip->i_cowfp->if_seq) << 32; |
64 | return cookie | READ_ONCE(ip->i_df.if_seq); |
65 | } |
66 | |
67 | /* |
68 | * Check that the iomap passed to us is still valid for the given offset and |
69 | * length. |
70 | */ |
71 | static bool |
72 | xfs_iomap_valid( |
73 | struct inode *inode, |
74 | const struct iomap *iomap) |
75 | { |
76 | struct xfs_inode *ip = XFS_I(inode); |
77 | |
78 | if (iomap->validity_cookie != |
79 | xfs_iomap_inode_sequence(ip, iomap_flags: iomap->flags)) { |
80 | trace_xfs_iomap_invalid(ip, iomap); |
81 | return false; |
82 | } |
83 | |
84 | XFS_ERRORTAG_DELAY(ip->i_mount, XFS_ERRTAG_WRITE_DELAY_MS); |
85 | return true; |
86 | } |
87 | |
88 | static const struct iomap_folio_ops xfs_iomap_folio_ops = { |
89 | .iomap_valid = xfs_iomap_valid, |
90 | }; |
91 | |
92 | int |
93 | xfs_bmbt_to_iomap( |
94 | struct xfs_inode *ip, |
95 | struct iomap *iomap, |
96 | struct xfs_bmbt_irec *imap, |
97 | unsigned int mapping_flags, |
98 | u16 iomap_flags, |
99 | u64 sequence_cookie) |
100 | { |
101 | struct xfs_mount *mp = ip->i_mount; |
102 | struct xfs_buftarg *target = xfs_inode_buftarg(ip); |
103 | |
104 | if (unlikely(!xfs_valid_startblock(ip, imap->br_startblock))) { |
105 | xfs_bmap_mark_sick(ip, XFS_DATA_FORK); |
106 | return xfs_alert_fsblock_zero(ip, imap); |
107 | } |
108 | |
109 | if (imap->br_startblock == HOLESTARTBLOCK) { |
110 | iomap->addr = IOMAP_NULL_ADDR; |
111 | iomap->type = IOMAP_HOLE; |
112 | } else if (imap->br_startblock == DELAYSTARTBLOCK || |
113 | isnullstartblock(imap->br_startblock)) { |
114 | iomap->addr = IOMAP_NULL_ADDR; |
115 | iomap->type = IOMAP_DELALLOC; |
116 | } else { |
117 | iomap->addr = BBTOB(xfs_fsb_to_db(ip, imap->br_startblock)); |
118 | if (mapping_flags & IOMAP_DAX) |
119 | iomap->addr += target->bt_dax_part_off; |
120 | |
121 | if (imap->br_state == XFS_EXT_UNWRITTEN) |
122 | iomap->type = IOMAP_UNWRITTEN; |
123 | else |
124 | iomap->type = IOMAP_MAPPED; |
125 | |
126 | } |
127 | iomap->offset = XFS_FSB_TO_B(mp, imap->br_startoff); |
128 | iomap->length = XFS_FSB_TO_B(mp, imap->br_blockcount); |
129 | if (mapping_flags & IOMAP_DAX) |
130 | iomap->dax_dev = target->bt_daxdev; |
131 | else |
132 | iomap->bdev = target->bt_bdev; |
133 | iomap->flags = iomap_flags; |
134 | |
135 | if (xfs_ipincount(ip) && |
136 | (ip->i_itemp->ili_fsync_fields & ~XFS_ILOG_TIMESTAMP)) |
137 | iomap->flags |= IOMAP_F_DIRTY; |
138 | |
139 | iomap->validity_cookie = sequence_cookie; |
140 | iomap->folio_ops = &xfs_iomap_folio_ops; |
141 | return 0; |
142 | } |
143 | |
144 | static void |
145 | xfs_hole_to_iomap( |
146 | struct xfs_inode *ip, |
147 | struct iomap *iomap, |
148 | xfs_fileoff_t offset_fsb, |
149 | xfs_fileoff_t end_fsb) |
150 | { |
151 | struct xfs_buftarg *target = xfs_inode_buftarg(ip); |
152 | |
153 | iomap->addr = IOMAP_NULL_ADDR; |
154 | iomap->type = IOMAP_HOLE; |
155 | iomap->offset = XFS_FSB_TO_B(ip->i_mount, offset_fsb); |
156 | iomap->length = XFS_FSB_TO_B(ip->i_mount, end_fsb - offset_fsb); |
157 | iomap->bdev = target->bt_bdev; |
158 | iomap->dax_dev = target->bt_daxdev; |
159 | } |
160 | |
161 | static inline xfs_fileoff_t |
162 | xfs_iomap_end_fsb( |
163 | struct xfs_mount *mp, |
164 | loff_t offset, |
165 | loff_t count) |
166 | { |
167 | ASSERT(offset <= mp->m_super->s_maxbytes); |
168 | return min(XFS_B_TO_FSB(mp, offset + count), |
169 | XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes)); |
170 | } |
171 | |
172 | static xfs_extlen_t |
173 | xfs_eof_alignment( |
174 | struct xfs_inode *ip) |
175 | { |
176 | struct xfs_mount *mp = ip->i_mount; |
177 | xfs_extlen_t align = 0; |
178 | |
179 | if (!XFS_IS_REALTIME_INODE(ip)) { |
180 | /* |
181 | * Round up the allocation request to a stripe unit |
182 | * (m_dalign) boundary if the file size is >= stripe unit |
183 | * size, and we are allocating past the allocation eof. |
184 | * |
185 | * If mounted with the "-o swalloc" option the alignment is |
186 | * increased from the strip unit size to the stripe width. |
187 | */ |
188 | if (mp->m_swidth && xfs_has_swalloc(mp)) |
189 | align = mp->m_swidth; |
190 | else if (mp->m_dalign) |
191 | align = mp->m_dalign; |
192 | |
193 | if (align && XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, align)) |
194 | align = 0; |
195 | } |
196 | |
197 | return align; |
198 | } |
199 | |
200 | /* |
201 | * Check if last_fsb is outside the last extent, and if so grow it to the next |
202 | * stripe unit boundary. |
203 | */ |
204 | xfs_fileoff_t |
205 | xfs_iomap_eof_align_last_fsb( |
206 | struct xfs_inode *ip, |
207 | xfs_fileoff_t end_fsb) |
208 | { |
209 | struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK); |
210 | xfs_extlen_t extsz = xfs_get_extsz_hint(ip); |
211 | xfs_extlen_t align = xfs_eof_alignment(ip); |
212 | struct xfs_bmbt_irec irec; |
213 | struct xfs_iext_cursor icur; |
214 | |
215 | ASSERT(!xfs_need_iread_extents(ifp)); |
216 | |
217 | /* |
218 | * Always round up the allocation request to the extent hint boundary. |
219 | */ |
220 | if (extsz) { |
221 | if (align) |
222 | align = roundup_64(align, extsz); |
223 | else |
224 | align = extsz; |
225 | } |
226 | |
227 | if (align) { |
228 | xfs_fileoff_t aligned_end_fsb = roundup_64(end_fsb, align); |
229 | |
230 | xfs_iext_last(ifp, &icur); |
231 | if (!xfs_iext_get_extent(ifp, &icur, &irec) || |
232 | aligned_end_fsb >= irec.br_startoff + irec.br_blockcount) |
233 | return aligned_end_fsb; |
234 | } |
235 | |
236 | return end_fsb; |
237 | } |
238 | |
239 | int |
240 | xfs_iomap_write_direct( |
241 | struct xfs_inode *ip, |
242 | xfs_fileoff_t offset_fsb, |
243 | xfs_fileoff_t count_fsb, |
244 | unsigned int flags, |
245 | struct xfs_bmbt_irec *imap, |
246 | u64 *seq) |
247 | { |
248 | struct xfs_mount *mp = ip->i_mount; |
249 | struct xfs_trans *tp; |
250 | xfs_filblks_t resaligned; |
251 | int nimaps; |
252 | unsigned int dblocks, rblocks; |
253 | bool force = false; |
254 | int error; |
255 | int bmapi_flags = XFS_BMAPI_PREALLOC; |
256 | int nr_exts = XFS_IEXT_ADD_NOSPLIT_CNT; |
257 | |
258 | ASSERT(count_fsb > 0); |
259 | |
260 | resaligned = xfs_aligned_fsb_count(offset_fsb, count_fsb, |
261 | xfs_get_extsz_hint(ip)); |
262 | if (unlikely(XFS_IS_REALTIME_INODE(ip))) { |
263 | dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); |
264 | rblocks = resaligned; |
265 | } else { |
266 | dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); |
267 | rblocks = 0; |
268 | } |
269 | |
270 | error = xfs_qm_dqattach(ip); |
271 | if (error) |
272 | return error; |
273 | |
274 | /* |
275 | * For DAX, we do not allocate unwritten extents, but instead we zero |
276 | * the block before we commit the transaction. Ideally we'd like to do |
277 | * this outside the transaction context, but if we commit and then crash |
278 | * we may not have zeroed the blocks and this will be exposed on |
279 | * recovery of the allocation. Hence we must zero before commit. |
280 | * |
281 | * Further, if we are mapping unwritten extents here, we need to zero |
282 | * and convert them to written so that we don't need an unwritten extent |
283 | * callback for DAX. This also means that we need to be able to dip into |
284 | * the reserve block pool for bmbt block allocation if there is no space |
285 | * left but we need to do unwritten extent conversion. |
286 | */ |
287 | if (flags & IOMAP_DAX) { |
288 | bmapi_flags = XFS_BMAPI_CONVERT | XFS_BMAPI_ZERO; |
289 | if (imap->br_state == XFS_EXT_UNWRITTEN) { |
290 | force = true; |
291 | nr_exts = XFS_IEXT_WRITE_UNWRITTEN_CNT; |
292 | dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1; |
293 | } |
294 | } |
295 | |
296 | error = xfs_trans_alloc_inode(ip, resv: &M_RES(mp)->tr_write, dblocks, |
297 | rblocks, force, tpp: &tp); |
298 | if (error) |
299 | return error; |
300 | |
301 | error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, nr_exts); |
302 | if (error == -EFBIG) |
303 | error = xfs_iext_count_upgrade(tp, ip, nr_exts); |
304 | if (error) |
305 | goto out_trans_cancel; |
306 | |
307 | /* |
308 | * From this point onwards we overwrite the imap pointer that the |
309 | * caller gave to us. |
310 | */ |
311 | nimaps = 1; |
312 | error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb, bmapi_flags, 0, |
313 | imap, &nimaps); |
314 | if (error) |
315 | goto out_trans_cancel; |
316 | |
317 | /* |
318 | * Complete the transaction |
319 | */ |
320 | error = xfs_trans_commit(tp); |
321 | if (error) |
322 | goto out_unlock; |
323 | |
324 | /* |
325 | * Copy any maps to caller's array and return any error. |
326 | */ |
327 | if (nimaps == 0) { |
328 | error = -ENOSPC; |
329 | goto out_unlock; |
330 | } |
331 | |
332 | if (unlikely(!xfs_valid_startblock(ip, imap->br_startblock))) { |
333 | xfs_bmap_mark_sick(ip, XFS_DATA_FORK); |
334 | error = xfs_alert_fsblock_zero(ip, imap); |
335 | } |
336 | |
337 | out_unlock: |
338 | *seq = xfs_iomap_inode_sequence(ip, iomap_flags: 0); |
339 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
340 | return error; |
341 | |
342 | out_trans_cancel: |
343 | xfs_trans_cancel(tp); |
344 | goto out_unlock; |
345 | } |
346 | |
347 | STATIC bool |
348 | xfs_quota_need_throttle( |
349 | struct xfs_inode *ip, |
350 | xfs_dqtype_t type, |
351 | xfs_fsblock_t alloc_blocks) |
352 | { |
353 | struct xfs_dquot *dq = xfs_inode_dquot(ip, type); |
354 | |
355 | if (!dq || !xfs_this_quota_on(ip->i_mount, type)) |
356 | return false; |
357 | |
358 | /* no hi watermark, no throttle */ |
359 | if (!dq->q_prealloc_hi_wmark) |
360 | return false; |
361 | |
362 | /* under the lo watermark, no throttle */ |
363 | if (dq->q_blk.reserved + alloc_blocks < dq->q_prealloc_lo_wmark) |
364 | return false; |
365 | |
366 | return true; |
367 | } |
368 | |
369 | STATIC void |
370 | xfs_quota_calc_throttle( |
371 | struct xfs_inode *ip, |
372 | xfs_dqtype_t type, |
373 | xfs_fsblock_t *qblocks, |
374 | int *qshift, |
375 | int64_t *qfreesp) |
376 | { |
377 | struct xfs_dquot *dq = xfs_inode_dquot(ip, type); |
378 | int64_t freesp; |
379 | int shift = 0; |
380 | |
381 | /* no dq, or over hi wmark, squash the prealloc completely */ |
382 | if (!dq || dq->q_blk.reserved >= dq->q_prealloc_hi_wmark) { |
383 | *qblocks = 0; |
384 | *qfreesp = 0; |
385 | return; |
386 | } |
387 | |
388 | freesp = dq->q_prealloc_hi_wmark - dq->q_blk.reserved; |
389 | if (freesp < dq->q_low_space[XFS_QLOWSP_5_PCNT]) { |
390 | shift = 2; |
391 | if (freesp < dq->q_low_space[XFS_QLOWSP_3_PCNT]) |
392 | shift += 2; |
393 | if (freesp < dq->q_low_space[XFS_QLOWSP_1_PCNT]) |
394 | shift += 2; |
395 | } |
396 | |
397 | if (freesp < *qfreesp) |
398 | *qfreesp = freesp; |
399 | |
400 | /* only overwrite the throttle values if we are more aggressive */ |
401 | if ((freesp >> shift) < (*qblocks >> *qshift)) { |
402 | *qblocks = freesp; |
403 | *qshift = shift; |
404 | } |
405 | } |
406 | |
407 | /* |
408 | * If we don't have a user specified preallocation size, dynamically increase |
409 | * the preallocation size as the size of the file grows. Cap the maximum size |
410 | * at a single extent or less if the filesystem is near full. The closer the |
411 | * filesystem is to being full, the smaller the maximum preallocation. |
412 | */ |
413 | STATIC xfs_fsblock_t |
414 | xfs_iomap_prealloc_size( |
415 | struct xfs_inode *ip, |
416 | int whichfork, |
417 | loff_t offset, |
418 | loff_t count, |
419 | struct xfs_iext_cursor *icur) |
420 | { |
421 | struct xfs_iext_cursor ncur = *icur; |
422 | struct xfs_bmbt_irec prev, got; |
423 | struct xfs_mount *mp = ip->i_mount; |
424 | struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork); |
425 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
426 | int64_t freesp; |
427 | xfs_fsblock_t qblocks; |
428 | xfs_fsblock_t alloc_blocks = 0; |
429 | xfs_extlen_t plen; |
430 | int shift = 0; |
431 | int qshift = 0; |
432 | |
433 | /* |
434 | * As an exception we don't do any preallocation at all if the file is |
435 | * smaller than the minimum preallocation and we are using the default |
436 | * dynamic preallocation scheme, as it is likely this is the only write |
437 | * to the file that is going to be done. |
438 | */ |
439 | if (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_allocsize_blocks)) |
440 | return 0; |
441 | |
442 | /* |
443 | * Use the minimum preallocation size for small files or if we are |
444 | * writing right after a hole. |
445 | */ |
446 | if (XFS_ISIZE(ip) < XFS_FSB_TO_B(mp, mp->m_dalign) || |
447 | !xfs_iext_prev_extent(ifp, &ncur, &prev) || |
448 | prev.br_startoff + prev.br_blockcount < offset_fsb) |
449 | return mp->m_allocsize_blocks; |
450 | |
451 | /* |
452 | * Take the size of the preceding data extents as the basis for the |
453 | * preallocation size. Note that we don't care if the previous extents |
454 | * are written or not. |
455 | */ |
456 | plen = prev.br_blockcount; |
457 | while (xfs_iext_prev_extent(ifp, &ncur, &got)) { |
458 | if (plen > XFS_MAX_BMBT_EXTLEN / 2 || |
459 | isnullstartblock(got.br_startblock) || |
460 | got.br_startoff + got.br_blockcount != prev.br_startoff || |
461 | got.br_startblock + got.br_blockcount != prev.br_startblock) |
462 | break; |
463 | plen += got.br_blockcount; |
464 | prev = got; |
465 | } |
466 | |
467 | /* |
468 | * If the size of the extents is greater than half the maximum extent |
469 | * length, then use the current offset as the basis. This ensures that |
470 | * for large files the preallocation size always extends to |
471 | * XFS_BMBT_MAX_EXTLEN rather than falling short due to things like stripe |
472 | * unit/width alignment of real extents. |
473 | */ |
474 | alloc_blocks = plen * 2; |
475 | if (alloc_blocks > XFS_MAX_BMBT_EXTLEN) |
476 | alloc_blocks = XFS_B_TO_FSB(mp, offset); |
477 | qblocks = alloc_blocks; |
478 | |
479 | /* |
480 | * XFS_BMBT_MAX_EXTLEN is not a power of two value but we round the prealloc |
481 | * down to the nearest power of two value after throttling. To prevent |
482 | * the round down from unconditionally reducing the maximum supported |
483 | * prealloc size, we round up first, apply appropriate throttling, round |
484 | * down and cap the value to XFS_BMBT_MAX_EXTLEN. |
485 | */ |
486 | alloc_blocks = XFS_FILEOFF_MIN(roundup_pow_of_two(XFS_MAX_BMBT_EXTLEN), |
487 | alloc_blocks); |
488 | |
489 | freesp = percpu_counter_read_positive(fbc: &mp->m_fdblocks); |
490 | if (freesp < mp->m_low_space[XFS_LOWSP_5_PCNT]) { |
491 | shift = 2; |
492 | if (freesp < mp->m_low_space[XFS_LOWSP_4_PCNT]) |
493 | shift++; |
494 | if (freesp < mp->m_low_space[XFS_LOWSP_3_PCNT]) |
495 | shift++; |
496 | if (freesp < mp->m_low_space[XFS_LOWSP_2_PCNT]) |
497 | shift++; |
498 | if (freesp < mp->m_low_space[XFS_LOWSP_1_PCNT]) |
499 | shift++; |
500 | } |
501 | |
502 | /* |
503 | * Check each quota to cap the prealloc size, provide a shift value to |
504 | * throttle with and adjust amount of available space. |
505 | */ |
506 | if (xfs_quota_need_throttle(ip, XFS_DQTYPE_USER, alloc_blocks)) |
507 | xfs_quota_calc_throttle(ip, XFS_DQTYPE_USER, &qblocks, &qshift, |
508 | &freesp); |
509 | if (xfs_quota_need_throttle(ip, XFS_DQTYPE_GROUP, alloc_blocks)) |
510 | xfs_quota_calc_throttle(ip, XFS_DQTYPE_GROUP, &qblocks, &qshift, |
511 | &freesp); |
512 | if (xfs_quota_need_throttle(ip, XFS_DQTYPE_PROJ, alloc_blocks)) |
513 | xfs_quota_calc_throttle(ip, XFS_DQTYPE_PROJ, &qblocks, &qshift, |
514 | &freesp); |
515 | |
516 | /* |
517 | * The final prealloc size is set to the minimum of free space available |
518 | * in each of the quotas and the overall filesystem. |
519 | * |
520 | * The shift throttle value is set to the maximum value as determined by |
521 | * the global low free space values and per-quota low free space values. |
522 | */ |
523 | alloc_blocks = min(alloc_blocks, qblocks); |
524 | shift = max(shift, qshift); |
525 | |
526 | if (shift) |
527 | alloc_blocks >>= shift; |
528 | /* |
529 | * rounddown_pow_of_two() returns an undefined result if we pass in |
530 | * alloc_blocks = 0. |
531 | */ |
532 | if (alloc_blocks) |
533 | alloc_blocks = rounddown_pow_of_two(alloc_blocks); |
534 | if (alloc_blocks > XFS_MAX_BMBT_EXTLEN) |
535 | alloc_blocks = XFS_MAX_BMBT_EXTLEN; |
536 | |
537 | /* |
538 | * If we are still trying to allocate more space than is |
539 | * available, squash the prealloc hard. This can happen if we |
540 | * have a large file on a small filesystem and the above |
541 | * lowspace thresholds are smaller than XFS_BMBT_MAX_EXTLEN. |
542 | */ |
543 | while (alloc_blocks && alloc_blocks >= freesp) |
544 | alloc_blocks >>= 4; |
545 | if (alloc_blocks < mp->m_allocsize_blocks) |
546 | alloc_blocks = mp->m_allocsize_blocks; |
547 | trace_xfs_iomap_prealloc_size(ip, alloc_blocks, shift, |
548 | mp->m_allocsize_blocks); |
549 | return alloc_blocks; |
550 | } |
551 | |
552 | int |
553 | xfs_iomap_write_unwritten( |
554 | xfs_inode_t *ip, |
555 | xfs_off_t offset, |
556 | xfs_off_t count, |
557 | bool update_isize) |
558 | { |
559 | xfs_mount_t *mp = ip->i_mount; |
560 | xfs_fileoff_t offset_fsb; |
561 | xfs_filblks_t count_fsb; |
562 | xfs_filblks_t numblks_fsb; |
563 | int nimaps; |
564 | xfs_trans_t *tp; |
565 | xfs_bmbt_irec_t imap; |
566 | struct inode *inode = VFS_I(ip); |
567 | xfs_fsize_t i_size; |
568 | uint resblks; |
569 | int error; |
570 | |
571 | trace_xfs_unwritten_convert(ip, offset, count); |
572 | |
573 | offset_fsb = XFS_B_TO_FSBT(mp, offset); |
574 | count_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count); |
575 | count_fsb = (xfs_filblks_t)(count_fsb - offset_fsb); |
576 | |
577 | /* |
578 | * Reserve enough blocks in this transaction for two complete extent |
579 | * btree splits. We may be converting the middle part of an unwritten |
580 | * extent and in this case we will insert two new extents in the btree |
581 | * each of which could cause a full split. |
582 | * |
583 | * This reservation amount will be used in the first call to |
584 | * xfs_bmbt_split() to select an AG with enough space to satisfy the |
585 | * rest of the operation. |
586 | */ |
587 | resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0) << 1; |
588 | |
589 | /* Attach dquots so that bmbt splits are accounted correctly. */ |
590 | error = xfs_qm_dqattach(ip); |
591 | if (error) |
592 | return error; |
593 | |
594 | do { |
595 | /* |
596 | * Set up a transaction to convert the range of extents |
597 | * from unwritten to real. Do allocations in a loop until |
598 | * we have covered the range passed in. |
599 | * |
600 | * Note that we can't risk to recursing back into the filesystem |
601 | * here as we might be asked to write out the same inode that we |
602 | * complete here and might deadlock on the iolock. |
603 | */ |
604 | error = xfs_trans_alloc_inode(ip, resv: &M_RES(mp)->tr_write, dblocks: resblks, |
605 | rblocks: 0, force: true, tpp: &tp); |
606 | if (error) |
607 | return error; |
608 | |
609 | error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, |
610 | XFS_IEXT_WRITE_UNWRITTEN_CNT); |
611 | if (error == -EFBIG) |
612 | error = xfs_iext_count_upgrade(tp, ip, |
613 | XFS_IEXT_WRITE_UNWRITTEN_CNT); |
614 | if (error) |
615 | goto error_on_bmapi_transaction; |
616 | |
617 | /* |
618 | * Modify the unwritten extent state of the buffer. |
619 | */ |
620 | nimaps = 1; |
621 | error = xfs_bmapi_write(tp, ip, offset_fsb, count_fsb, |
622 | XFS_BMAPI_CONVERT, resblks, &imap, |
623 | &nimaps); |
624 | if (error) |
625 | goto error_on_bmapi_transaction; |
626 | |
627 | /* |
628 | * Log the updated inode size as we go. We have to be careful |
629 | * to only log it up to the actual write offset if it is |
630 | * halfway into a block. |
631 | */ |
632 | i_size = XFS_FSB_TO_B(mp, offset_fsb + count_fsb); |
633 | if (i_size > offset + count) |
634 | i_size = offset + count; |
635 | if (update_isize && i_size > i_size_read(inode)) |
636 | i_size_write(inode, i_size); |
637 | i_size = xfs_new_eof(ip, i_size); |
638 | if (i_size) { |
639 | ip->i_disk_size = i_size; |
640 | xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); |
641 | } |
642 | |
643 | error = xfs_trans_commit(tp); |
644 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
645 | if (error) |
646 | return error; |
647 | |
648 | if (unlikely(!xfs_valid_startblock(ip, imap.br_startblock))) { |
649 | xfs_bmap_mark_sick(ip, XFS_DATA_FORK); |
650 | return xfs_alert_fsblock_zero(ip, &imap); |
651 | } |
652 | |
653 | if ((numblks_fsb = imap.br_blockcount) == 0) { |
654 | /* |
655 | * The numblks_fsb value should always get |
656 | * smaller, otherwise the loop is stuck. |
657 | */ |
658 | ASSERT(imap.br_blockcount); |
659 | break; |
660 | } |
661 | offset_fsb += numblks_fsb; |
662 | count_fsb -= numblks_fsb; |
663 | } while (count_fsb > 0); |
664 | |
665 | return 0; |
666 | |
667 | error_on_bmapi_transaction: |
668 | xfs_trans_cancel(tp); |
669 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
670 | return error; |
671 | } |
672 | |
673 | static inline bool |
674 | imap_needs_alloc( |
675 | struct inode *inode, |
676 | unsigned flags, |
677 | struct xfs_bmbt_irec *imap, |
678 | int nimaps) |
679 | { |
680 | /* don't allocate blocks when just zeroing */ |
681 | if (flags & IOMAP_ZERO) |
682 | return false; |
683 | if (!nimaps || |
684 | imap->br_startblock == HOLESTARTBLOCK || |
685 | imap->br_startblock == DELAYSTARTBLOCK) |
686 | return true; |
687 | /* we convert unwritten extents before copying the data for DAX */ |
688 | if ((flags & IOMAP_DAX) && imap->br_state == XFS_EXT_UNWRITTEN) |
689 | return true; |
690 | return false; |
691 | } |
692 | |
693 | static inline bool |
694 | imap_needs_cow( |
695 | struct xfs_inode *ip, |
696 | unsigned int flags, |
697 | struct xfs_bmbt_irec *imap, |
698 | int nimaps) |
699 | { |
700 | if (!xfs_is_cow_inode(ip)) |
701 | return false; |
702 | |
703 | /* when zeroing we don't have to COW holes or unwritten extents */ |
704 | if (flags & IOMAP_ZERO) { |
705 | if (!nimaps || |
706 | imap->br_startblock == HOLESTARTBLOCK || |
707 | imap->br_state == XFS_EXT_UNWRITTEN) |
708 | return false; |
709 | } |
710 | |
711 | return true; |
712 | } |
713 | |
714 | static int |
715 | xfs_ilock_for_iomap( |
716 | struct xfs_inode *ip, |
717 | unsigned flags, |
718 | unsigned *lockmode) |
719 | { |
720 | unsigned int mode = *lockmode; |
721 | bool is_write = flags & (IOMAP_WRITE | IOMAP_ZERO); |
722 | |
723 | /* |
724 | * COW writes may allocate delalloc space or convert unwritten COW |
725 | * extents, so we need to make sure to take the lock exclusively here. |
726 | */ |
727 | if (xfs_is_cow_inode(ip) && is_write) |
728 | mode = XFS_ILOCK_EXCL; |
729 | |
730 | /* |
731 | * Extents not yet cached requires exclusive access, don't block. This |
732 | * is an opencoded xfs_ilock_data_map_shared() call but with |
733 | * non-blocking behaviour. |
734 | */ |
735 | if (xfs_need_iread_extents(&ip->i_df)) { |
736 | if (flags & IOMAP_NOWAIT) |
737 | return -EAGAIN; |
738 | mode = XFS_ILOCK_EXCL; |
739 | } |
740 | |
741 | relock: |
742 | if (flags & IOMAP_NOWAIT) { |
743 | if (!xfs_ilock_nowait(ip, mode)) |
744 | return -EAGAIN; |
745 | } else { |
746 | xfs_ilock(ip, mode); |
747 | } |
748 | |
749 | /* |
750 | * The reflink iflag could have changed since the earlier unlocked |
751 | * check, so if we got ILOCK_SHARED for a write and but we're now a |
752 | * reflink inode we have to switch to ILOCK_EXCL and relock. |
753 | */ |
754 | if (mode == XFS_ILOCK_SHARED && is_write && xfs_is_cow_inode(ip)) { |
755 | xfs_iunlock(ip, mode); |
756 | mode = XFS_ILOCK_EXCL; |
757 | goto relock; |
758 | } |
759 | |
760 | *lockmode = mode; |
761 | return 0; |
762 | } |
763 | |
764 | /* |
765 | * Check that the imap we are going to return to the caller spans the entire |
766 | * range that the caller requested for the IO. |
767 | */ |
768 | static bool |
769 | imap_spans_range( |
770 | struct xfs_bmbt_irec *imap, |
771 | xfs_fileoff_t offset_fsb, |
772 | xfs_fileoff_t end_fsb) |
773 | { |
774 | if (imap->br_startoff > offset_fsb) |
775 | return false; |
776 | if (imap->br_startoff + imap->br_blockcount < end_fsb) |
777 | return false; |
778 | return true; |
779 | } |
780 | |
781 | static int |
782 | xfs_direct_write_iomap_begin( |
783 | struct inode *inode, |
784 | loff_t offset, |
785 | loff_t length, |
786 | unsigned flags, |
787 | struct iomap *iomap, |
788 | struct iomap *srcmap) |
789 | { |
790 | struct xfs_inode *ip = XFS_I(inode); |
791 | struct xfs_mount *mp = ip->i_mount; |
792 | struct xfs_bmbt_irec imap, cmap; |
793 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
794 | xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length); |
795 | int nimaps = 1, error = 0; |
796 | bool shared = false; |
797 | u16 iomap_flags = 0; |
798 | unsigned int lockmode = XFS_ILOCK_SHARED; |
799 | u64 seq; |
800 | |
801 | ASSERT(flags & (IOMAP_WRITE | IOMAP_ZERO)); |
802 | |
803 | if (xfs_is_shutdown(mp)) |
804 | return -EIO; |
805 | |
806 | /* |
807 | * Writes that span EOF might trigger an IO size update on completion, |
808 | * so consider them to be dirty for the purposes of O_DSYNC even if |
809 | * there is no other metadata changes pending or have been made here. |
810 | */ |
811 | if (offset + length > i_size_read(inode)) |
812 | iomap_flags |= IOMAP_F_DIRTY; |
813 | |
814 | error = xfs_ilock_for_iomap(ip, flags, lockmode: &lockmode); |
815 | if (error) |
816 | return error; |
817 | |
818 | error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, |
819 | &nimaps, 0); |
820 | if (error) |
821 | goto out_unlock; |
822 | |
823 | if (imap_needs_cow(ip, flags, imap: &imap, nimaps)) { |
824 | error = -EAGAIN; |
825 | if (flags & IOMAP_NOWAIT) |
826 | goto out_unlock; |
827 | |
828 | /* may drop and re-acquire the ilock */ |
829 | error = xfs_reflink_allocate_cow(ip, imap: &imap, cmap: &cmap, shared: &shared, |
830 | lockmode: &lockmode, |
831 | convert_now: (flags & IOMAP_DIRECT) || IS_DAX(inode)); |
832 | if (error) |
833 | goto out_unlock; |
834 | if (shared) |
835 | goto out_found_cow; |
836 | end_fsb = imap.br_startoff + imap.br_blockcount; |
837 | length = XFS_FSB_TO_B(mp, end_fsb) - offset; |
838 | } |
839 | |
840 | if (imap_needs_alloc(inode, flags, imap: &imap, nimaps)) |
841 | goto allocate_blocks; |
842 | |
843 | /* |
844 | * NOWAIT and OVERWRITE I/O needs to span the entire requested I/O with |
845 | * a single map so that we avoid partial IO failures due to the rest of |
846 | * the I/O range not covered by this map triggering an EAGAIN condition |
847 | * when it is subsequently mapped and aborting the I/O. |
848 | */ |
849 | if (flags & (IOMAP_NOWAIT | IOMAP_OVERWRITE_ONLY)) { |
850 | error = -EAGAIN; |
851 | if (!imap_spans_range(&imap, offset_fsb, end_fsb)) |
852 | goto out_unlock; |
853 | } |
854 | |
855 | /* |
856 | * For overwrite only I/O, we cannot convert unwritten extents without |
857 | * requiring sub-block zeroing. This can only be done under an |
858 | * exclusive IOLOCK, hence return -EAGAIN if this is not a written |
859 | * extent to tell the caller to try again. |
860 | */ |
861 | if (flags & IOMAP_OVERWRITE_ONLY) { |
862 | error = -EAGAIN; |
863 | if (imap.br_state != XFS_EXT_NORM && |
864 | ((offset | length) & mp->m_blockmask)) |
865 | goto out_unlock; |
866 | } |
867 | |
868 | seq = xfs_iomap_inode_sequence(ip, iomap_flags); |
869 | xfs_iunlock(ip, lockmode); |
870 | trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); |
871 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, iomap_flags, sequence_cookie: seq); |
872 | |
873 | allocate_blocks: |
874 | error = -EAGAIN; |
875 | if (flags & (IOMAP_NOWAIT | IOMAP_OVERWRITE_ONLY)) |
876 | goto out_unlock; |
877 | |
878 | /* |
879 | * We cap the maximum length we map to a sane size to keep the chunks |
880 | * of work done where somewhat symmetric with the work writeback does. |
881 | * This is a completely arbitrary number pulled out of thin air as a |
882 | * best guess for initial testing. |
883 | * |
884 | * Note that the values needs to be less than 32-bits wide until the |
885 | * lower level functions are updated. |
886 | */ |
887 | length = min_t(loff_t, length, 1024 * PAGE_SIZE); |
888 | end_fsb = xfs_iomap_end_fsb(mp, offset, length); |
889 | |
890 | if (offset + length > XFS_ISIZE(ip)) |
891 | end_fsb = xfs_iomap_eof_align_last_fsb(ip, end_fsb); |
892 | else if (nimaps && imap.br_startblock == HOLESTARTBLOCK) |
893 | end_fsb = min(end_fsb, imap.br_startoff + imap.br_blockcount); |
894 | xfs_iunlock(ip, lockmode); |
895 | |
896 | error = xfs_iomap_write_direct(ip, offset_fsb, end_fsb - offset_fsb, |
897 | flags, &imap, &seq); |
898 | if (error) |
899 | return error; |
900 | |
901 | trace_xfs_iomap_alloc(ip, offset, length, XFS_DATA_FORK, &imap); |
902 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, |
903 | iomap_flags: iomap_flags | IOMAP_F_NEW, sequence_cookie: seq); |
904 | |
905 | out_found_cow: |
906 | length = XFS_FSB_TO_B(mp, cmap.br_startoff + cmap.br_blockcount); |
907 | trace_xfs_iomap_found(ip, offset, length - offset, XFS_COW_FORK, &cmap); |
908 | if (imap.br_startblock != HOLESTARTBLOCK) { |
909 | seq = xfs_iomap_inode_sequence(ip, iomap_flags: 0); |
910 | error = xfs_bmbt_to_iomap(ip, iomap: srcmap, imap: &imap, mapping_flags: flags, iomap_flags: 0, sequence_cookie: seq); |
911 | if (error) |
912 | goto out_unlock; |
913 | } |
914 | seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); |
915 | xfs_iunlock(ip, lockmode); |
916 | return xfs_bmbt_to_iomap(ip, iomap, imap: &cmap, mapping_flags: flags, IOMAP_F_SHARED, sequence_cookie: seq); |
917 | |
918 | out_unlock: |
919 | if (lockmode) |
920 | xfs_iunlock(ip, lockmode); |
921 | return error; |
922 | } |
923 | |
924 | const struct iomap_ops xfs_direct_write_iomap_ops = { |
925 | .iomap_begin = xfs_direct_write_iomap_begin, |
926 | }; |
927 | |
928 | static int |
929 | xfs_dax_write_iomap_end( |
930 | struct inode *inode, |
931 | loff_t pos, |
932 | loff_t length, |
933 | ssize_t written, |
934 | unsigned flags, |
935 | struct iomap *iomap) |
936 | { |
937 | struct xfs_inode *ip = XFS_I(inode); |
938 | |
939 | if (!xfs_is_cow_inode(ip)) |
940 | return 0; |
941 | |
942 | if (!written) { |
943 | xfs_reflink_cancel_cow_range(ip, offset: pos, count: length, cancel_real: true); |
944 | return 0; |
945 | } |
946 | |
947 | return xfs_reflink_end_cow(ip, offset: pos, count: written); |
948 | } |
949 | |
950 | const struct iomap_ops xfs_dax_write_iomap_ops = { |
951 | .iomap_begin = xfs_direct_write_iomap_begin, |
952 | .iomap_end = xfs_dax_write_iomap_end, |
953 | }; |
954 | |
955 | static int |
956 | xfs_buffered_write_iomap_begin( |
957 | struct inode *inode, |
958 | loff_t offset, |
959 | loff_t count, |
960 | unsigned flags, |
961 | struct iomap *iomap, |
962 | struct iomap *srcmap) |
963 | { |
964 | struct xfs_inode *ip = XFS_I(inode); |
965 | struct xfs_mount *mp = ip->i_mount; |
966 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
967 | xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, count); |
968 | struct xfs_bmbt_irec imap, cmap; |
969 | struct xfs_iext_cursor icur, ccur; |
970 | xfs_fsblock_t prealloc_blocks = 0; |
971 | bool eof = false, cow_eof = false, shared = false; |
972 | int allocfork = XFS_DATA_FORK; |
973 | int error = 0; |
974 | unsigned int lockmode = XFS_ILOCK_EXCL; |
975 | u64 seq; |
976 | |
977 | if (xfs_is_shutdown(mp)) |
978 | return -EIO; |
979 | |
980 | /* we can't use delayed allocations when using extent size hints */ |
981 | if (xfs_get_extsz_hint(ip)) |
982 | return xfs_direct_write_iomap_begin(inode, offset, length: count, |
983 | flags, iomap, srcmap); |
984 | |
985 | ASSERT(!XFS_IS_REALTIME_INODE(ip)); |
986 | |
987 | error = xfs_qm_dqattach(ip); |
988 | if (error) |
989 | return error; |
990 | |
991 | error = xfs_ilock_for_iomap(ip, flags, lockmode: &lockmode); |
992 | if (error) |
993 | return error; |
994 | |
995 | if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(&ip->i_df)) || |
996 | XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) { |
997 | xfs_bmap_mark_sick(ip, XFS_DATA_FORK); |
998 | error = -EFSCORRUPTED; |
999 | goto out_unlock; |
1000 | } |
1001 | |
1002 | XFS_STATS_INC(mp, xs_blk_mapw); |
1003 | |
1004 | error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK); |
1005 | if (error) |
1006 | goto out_unlock; |
1007 | |
1008 | /* |
1009 | * Search the data fork first to look up our source mapping. We |
1010 | * always need the data fork map, as we have to return it to the |
1011 | * iomap code so that the higher level write code can read data in to |
1012 | * perform read-modify-write cycles for unaligned writes. |
1013 | */ |
1014 | eof = !xfs_iext_lookup_extent(ip, &ip->i_df, offset_fsb, &icur, &imap); |
1015 | if (eof) |
1016 | imap.br_startoff = end_fsb; /* fake hole until the end */ |
1017 | |
1018 | /* We never need to allocate blocks for zeroing or unsharing a hole. */ |
1019 | if ((flags & (IOMAP_UNSHARE | IOMAP_ZERO)) && |
1020 | imap.br_startoff > offset_fsb) { |
1021 | xfs_hole_to_iomap(ip, iomap, offset_fsb, imap.br_startoff); |
1022 | goto out_unlock; |
1023 | } |
1024 | |
1025 | /* |
1026 | * Search the COW fork extent list even if we did not find a data fork |
1027 | * extent. This serves two purposes: first this implements the |
1028 | * speculative preallocation using cowextsize, so that we also unshare |
1029 | * block adjacent to shared blocks instead of just the shared blocks |
1030 | * themselves. Second the lookup in the extent list is generally faster |
1031 | * than going out to the shared extent tree. |
1032 | */ |
1033 | if (xfs_is_cow_inode(ip)) { |
1034 | if (!ip->i_cowfp) { |
1035 | ASSERT(!xfs_is_reflink_inode(ip)); |
1036 | xfs_ifork_init_cow(ip); |
1037 | } |
1038 | cow_eof = !xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, |
1039 | &ccur, &cmap); |
1040 | if (!cow_eof && cmap.br_startoff <= offset_fsb) { |
1041 | trace_xfs_reflink_cow_found(ip, irec: &cmap); |
1042 | goto found_cow; |
1043 | } |
1044 | } |
1045 | |
1046 | if (imap.br_startoff <= offset_fsb) { |
1047 | /* |
1048 | * For reflink files we may need a delalloc reservation when |
1049 | * overwriting shared extents. This includes zeroing of |
1050 | * existing extents that contain data. |
1051 | */ |
1052 | if (!xfs_is_cow_inode(ip) || |
1053 | ((flags & IOMAP_ZERO) && imap.br_state != XFS_EXT_NORM)) { |
1054 | trace_xfs_iomap_found(ip, offset, count, XFS_DATA_FORK, |
1055 | &imap); |
1056 | goto found_imap; |
1057 | } |
1058 | |
1059 | xfs_trim_extent(&imap, offset_fsb, end_fsb - offset_fsb); |
1060 | |
1061 | /* Trim the mapping to the nearest shared extent boundary. */ |
1062 | error = xfs_bmap_trim_cow(ip, imap: &imap, shared: &shared); |
1063 | if (error) |
1064 | goto out_unlock; |
1065 | |
1066 | /* Not shared? Just report the (potentially capped) extent. */ |
1067 | if (!shared) { |
1068 | trace_xfs_iomap_found(ip, offset, count, XFS_DATA_FORK, |
1069 | &imap); |
1070 | goto found_imap; |
1071 | } |
1072 | |
1073 | /* |
1074 | * Fork all the shared blocks from our write offset until the |
1075 | * end of the extent. |
1076 | */ |
1077 | allocfork = XFS_COW_FORK; |
1078 | end_fsb = imap.br_startoff + imap.br_blockcount; |
1079 | } else { |
1080 | /* |
1081 | * We cap the maximum length we map here to MAX_WRITEBACK_PAGES |
1082 | * pages to keep the chunks of work done where somewhat |
1083 | * symmetric with the work writeback does. This is a completely |
1084 | * arbitrary number pulled out of thin air. |
1085 | * |
1086 | * Note that the values needs to be less than 32-bits wide until |
1087 | * the lower level functions are updated. |
1088 | */ |
1089 | count = min_t(loff_t, count, 1024 * PAGE_SIZE); |
1090 | end_fsb = xfs_iomap_end_fsb(mp, offset, count); |
1091 | |
1092 | if (xfs_is_always_cow_inode(ip)) |
1093 | allocfork = XFS_COW_FORK; |
1094 | } |
1095 | |
1096 | if (eof && offset + count > XFS_ISIZE(ip)) { |
1097 | /* |
1098 | * Determine the initial size of the preallocation. |
1099 | * We clean up any extra preallocation when the file is closed. |
1100 | */ |
1101 | if (xfs_has_allocsize(mp)) |
1102 | prealloc_blocks = mp->m_allocsize_blocks; |
1103 | else if (allocfork == XFS_DATA_FORK) |
1104 | prealloc_blocks = xfs_iomap_prealloc_size(ip, allocfork, |
1105 | offset, count, &icur); |
1106 | else |
1107 | prealloc_blocks = xfs_iomap_prealloc_size(ip, allocfork, |
1108 | offset, count, &ccur); |
1109 | if (prealloc_blocks) { |
1110 | xfs_extlen_t align; |
1111 | xfs_off_t end_offset; |
1112 | xfs_fileoff_t p_end_fsb; |
1113 | |
1114 | end_offset = XFS_ALLOC_ALIGN(mp, offset + count - 1); |
1115 | p_end_fsb = XFS_B_TO_FSBT(mp, end_offset) + |
1116 | prealloc_blocks; |
1117 | |
1118 | align = xfs_eof_alignment(ip); |
1119 | if (align) |
1120 | p_end_fsb = roundup_64(p_end_fsb, align); |
1121 | |
1122 | p_end_fsb = min(p_end_fsb, |
1123 | XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes)); |
1124 | ASSERT(p_end_fsb > offset_fsb); |
1125 | prealloc_blocks = p_end_fsb - end_fsb; |
1126 | } |
1127 | } |
1128 | |
1129 | retry: |
1130 | error = xfs_bmapi_reserve_delalloc(ip, allocfork, offset_fsb, |
1131 | end_fsb - offset_fsb, prealloc_blocks, |
1132 | allocfork == XFS_DATA_FORK ? &imap : &cmap, |
1133 | allocfork == XFS_DATA_FORK ? &icur : &ccur, |
1134 | allocfork == XFS_DATA_FORK ? eof : cow_eof); |
1135 | switch (error) { |
1136 | case 0: |
1137 | break; |
1138 | case -ENOSPC: |
1139 | case -EDQUOT: |
1140 | /* retry without any preallocation */ |
1141 | trace_xfs_delalloc_enospc(ip, offset, count); |
1142 | if (prealloc_blocks) { |
1143 | prealloc_blocks = 0; |
1144 | goto retry; |
1145 | } |
1146 | fallthrough; |
1147 | default: |
1148 | goto out_unlock; |
1149 | } |
1150 | |
1151 | if (allocfork == XFS_COW_FORK) { |
1152 | trace_xfs_iomap_alloc(ip, offset, count, whichfork: allocfork, irec: &cmap); |
1153 | goto found_cow; |
1154 | } |
1155 | |
1156 | /* |
1157 | * Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch |
1158 | * them out if the write happens to fail. |
1159 | */ |
1160 | seq = xfs_iomap_inode_sequence(ip, IOMAP_F_NEW); |
1161 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
1162 | trace_xfs_iomap_alloc(ip, offset, count, whichfork: allocfork, irec: &imap); |
1163 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, IOMAP_F_NEW, sequence_cookie: seq); |
1164 | |
1165 | found_imap: |
1166 | seq = xfs_iomap_inode_sequence(ip, iomap_flags: 0); |
1167 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
1168 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, iomap_flags: 0, sequence_cookie: seq); |
1169 | |
1170 | found_cow: |
1171 | seq = xfs_iomap_inode_sequence(ip, iomap_flags: 0); |
1172 | if (imap.br_startoff <= offset_fsb) { |
1173 | error = xfs_bmbt_to_iomap(ip, iomap: srcmap, imap: &imap, mapping_flags: flags, iomap_flags: 0, sequence_cookie: seq); |
1174 | if (error) |
1175 | goto out_unlock; |
1176 | seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); |
1177 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
1178 | return xfs_bmbt_to_iomap(ip, iomap, imap: &cmap, mapping_flags: flags, |
1179 | IOMAP_F_SHARED, sequence_cookie: seq); |
1180 | } |
1181 | |
1182 | xfs_trim_extent(&cmap, offset_fsb, imap.br_startoff - offset_fsb); |
1183 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
1184 | return xfs_bmbt_to_iomap(ip, iomap, imap: &cmap, mapping_flags: flags, iomap_flags: 0, sequence_cookie: seq); |
1185 | |
1186 | out_unlock: |
1187 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
1188 | return error; |
1189 | } |
1190 | |
1191 | static int |
1192 | xfs_buffered_write_delalloc_punch( |
1193 | struct inode *inode, |
1194 | loff_t offset, |
1195 | loff_t length) |
1196 | { |
1197 | return xfs_bmap_punch_delalloc_range(ip: XFS_I(inode), start_byte: offset, |
1198 | end_byte: offset + length); |
1199 | } |
1200 | |
1201 | static int |
1202 | xfs_buffered_write_iomap_end( |
1203 | struct inode *inode, |
1204 | loff_t offset, |
1205 | loff_t length, |
1206 | ssize_t written, |
1207 | unsigned flags, |
1208 | struct iomap *iomap) |
1209 | { |
1210 | |
1211 | struct xfs_mount *mp = XFS_M(inode->i_sb); |
1212 | int error; |
1213 | |
1214 | error = iomap_file_buffered_write_punch_delalloc(inode, iomap, pos: offset, |
1215 | length, written, punch: &xfs_buffered_write_delalloc_punch); |
1216 | if (error && !xfs_is_shutdown(mp)) { |
1217 | xfs_alert(mp, "%s: unable to clean up ino 0x%llx" , |
1218 | __func__, XFS_I(inode)->i_ino); |
1219 | return error; |
1220 | } |
1221 | return 0; |
1222 | } |
1223 | |
1224 | const struct iomap_ops xfs_buffered_write_iomap_ops = { |
1225 | .iomap_begin = xfs_buffered_write_iomap_begin, |
1226 | .iomap_end = xfs_buffered_write_iomap_end, |
1227 | }; |
1228 | |
1229 | /* |
1230 | * iomap_page_mkwrite() will never fail in a way that requires delalloc extents |
1231 | * that it allocated to be revoked. Hence we do not need an .iomap_end method |
1232 | * for this operation. |
1233 | */ |
1234 | const struct iomap_ops xfs_page_mkwrite_iomap_ops = { |
1235 | .iomap_begin = xfs_buffered_write_iomap_begin, |
1236 | }; |
1237 | |
1238 | static int |
1239 | xfs_read_iomap_begin( |
1240 | struct inode *inode, |
1241 | loff_t offset, |
1242 | loff_t length, |
1243 | unsigned flags, |
1244 | struct iomap *iomap, |
1245 | struct iomap *srcmap) |
1246 | { |
1247 | struct xfs_inode *ip = XFS_I(inode); |
1248 | struct xfs_mount *mp = ip->i_mount; |
1249 | struct xfs_bmbt_irec imap; |
1250 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
1251 | xfs_fileoff_t end_fsb = xfs_iomap_end_fsb(mp, offset, length); |
1252 | int nimaps = 1, error = 0; |
1253 | bool shared = false; |
1254 | unsigned int lockmode = XFS_ILOCK_SHARED; |
1255 | u64 seq; |
1256 | |
1257 | ASSERT(!(flags & (IOMAP_WRITE | IOMAP_ZERO))); |
1258 | |
1259 | if (xfs_is_shutdown(mp)) |
1260 | return -EIO; |
1261 | |
1262 | error = xfs_ilock_for_iomap(ip, flags, lockmode: &lockmode); |
1263 | if (error) |
1264 | return error; |
1265 | error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, |
1266 | &nimaps, 0); |
1267 | if (!error && ((flags & IOMAP_REPORT) || IS_DAX(inode))) |
1268 | error = xfs_reflink_trim_around_shared(ip, irec: &imap, shared: &shared); |
1269 | seq = xfs_iomap_inode_sequence(ip, iomap_flags: shared ? IOMAP_F_SHARED : 0); |
1270 | xfs_iunlock(ip, lockmode); |
1271 | |
1272 | if (error) |
1273 | return error; |
1274 | trace_xfs_iomap_found(ip, offset, length, XFS_DATA_FORK, &imap); |
1275 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, |
1276 | iomap_flags: shared ? IOMAP_F_SHARED : 0, sequence_cookie: seq); |
1277 | } |
1278 | |
1279 | const struct iomap_ops xfs_read_iomap_ops = { |
1280 | .iomap_begin = xfs_read_iomap_begin, |
1281 | }; |
1282 | |
1283 | static int |
1284 | xfs_seek_iomap_begin( |
1285 | struct inode *inode, |
1286 | loff_t offset, |
1287 | loff_t length, |
1288 | unsigned flags, |
1289 | struct iomap *iomap, |
1290 | struct iomap *srcmap) |
1291 | { |
1292 | struct xfs_inode *ip = XFS_I(inode); |
1293 | struct xfs_mount *mp = ip->i_mount; |
1294 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
1295 | xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + length); |
1296 | xfs_fileoff_t cow_fsb = NULLFILEOFF, data_fsb = NULLFILEOFF; |
1297 | struct xfs_iext_cursor icur; |
1298 | struct xfs_bmbt_irec imap, cmap; |
1299 | int error = 0; |
1300 | unsigned lockmode; |
1301 | u64 seq; |
1302 | |
1303 | if (xfs_is_shutdown(mp)) |
1304 | return -EIO; |
1305 | |
1306 | lockmode = xfs_ilock_data_map_shared(ip); |
1307 | error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK); |
1308 | if (error) |
1309 | goto out_unlock; |
1310 | |
1311 | if (xfs_iext_lookup_extent(ip, &ip->i_df, offset_fsb, &icur, &imap)) { |
1312 | /* |
1313 | * If we found a data extent we are done. |
1314 | */ |
1315 | if (imap.br_startoff <= offset_fsb) |
1316 | goto done; |
1317 | data_fsb = imap.br_startoff; |
1318 | } else { |
1319 | /* |
1320 | * Fake a hole until the end of the file. |
1321 | */ |
1322 | data_fsb = xfs_iomap_end_fsb(mp, offset, length); |
1323 | } |
1324 | |
1325 | /* |
1326 | * If a COW fork extent covers the hole, report it - capped to the next |
1327 | * data fork extent: |
1328 | */ |
1329 | if (xfs_inode_has_cow_data(ip) && |
1330 | xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &cmap)) |
1331 | cow_fsb = cmap.br_startoff; |
1332 | if (cow_fsb != NULLFILEOFF && cow_fsb <= offset_fsb) { |
1333 | if (data_fsb < cow_fsb + cmap.br_blockcount) |
1334 | end_fsb = min(end_fsb, data_fsb); |
1335 | xfs_trim_extent(&cmap, offset_fsb, end_fsb - offset_fsb); |
1336 | seq = xfs_iomap_inode_sequence(ip, IOMAP_F_SHARED); |
1337 | error = xfs_bmbt_to_iomap(ip, iomap, imap: &cmap, mapping_flags: flags, |
1338 | IOMAP_F_SHARED, sequence_cookie: seq); |
1339 | /* |
1340 | * This is a COW extent, so we must probe the page cache |
1341 | * because there could be dirty page cache being backed |
1342 | * by this extent. |
1343 | */ |
1344 | iomap->type = IOMAP_UNWRITTEN; |
1345 | goto out_unlock; |
1346 | } |
1347 | |
1348 | /* |
1349 | * Else report a hole, capped to the next found data or COW extent. |
1350 | */ |
1351 | if (cow_fsb != NULLFILEOFF && cow_fsb < data_fsb) |
1352 | imap.br_blockcount = cow_fsb - offset_fsb; |
1353 | else |
1354 | imap.br_blockcount = data_fsb - offset_fsb; |
1355 | imap.br_startoff = offset_fsb; |
1356 | imap.br_startblock = HOLESTARTBLOCK; |
1357 | imap.br_state = XFS_EXT_NORM; |
1358 | done: |
1359 | seq = xfs_iomap_inode_sequence(ip, iomap_flags: 0); |
1360 | xfs_trim_extent(&imap, offset_fsb, end_fsb - offset_fsb); |
1361 | error = xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, iomap_flags: 0, sequence_cookie: seq); |
1362 | out_unlock: |
1363 | xfs_iunlock(ip, lockmode); |
1364 | return error; |
1365 | } |
1366 | |
1367 | const struct iomap_ops xfs_seek_iomap_ops = { |
1368 | .iomap_begin = xfs_seek_iomap_begin, |
1369 | }; |
1370 | |
1371 | static int |
1372 | xfs_xattr_iomap_begin( |
1373 | struct inode *inode, |
1374 | loff_t offset, |
1375 | loff_t length, |
1376 | unsigned flags, |
1377 | struct iomap *iomap, |
1378 | struct iomap *srcmap) |
1379 | { |
1380 | struct xfs_inode *ip = XFS_I(inode); |
1381 | struct xfs_mount *mp = ip->i_mount; |
1382 | xfs_fileoff_t offset_fsb = XFS_B_TO_FSBT(mp, offset); |
1383 | xfs_fileoff_t end_fsb = XFS_B_TO_FSB(mp, offset + length); |
1384 | struct xfs_bmbt_irec imap; |
1385 | int nimaps = 1, error = 0; |
1386 | unsigned lockmode; |
1387 | int seq; |
1388 | |
1389 | if (xfs_is_shutdown(mp)) |
1390 | return -EIO; |
1391 | |
1392 | lockmode = xfs_ilock_attr_map_shared(ip); |
1393 | |
1394 | /* if there are no attribute fork or extents, return ENOENT */ |
1395 | if (!xfs_inode_has_attr_fork(ip) || !ip->i_af.if_nextents) { |
1396 | error = -ENOENT; |
1397 | goto out_unlock; |
1398 | } |
1399 | |
1400 | ASSERT(ip->i_af.if_format != XFS_DINODE_FMT_LOCAL); |
1401 | error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap, |
1402 | &nimaps, XFS_BMAPI_ATTRFORK); |
1403 | out_unlock: |
1404 | |
1405 | seq = xfs_iomap_inode_sequence(ip, IOMAP_F_XATTR); |
1406 | xfs_iunlock(ip, lockmode); |
1407 | |
1408 | if (error) |
1409 | return error; |
1410 | ASSERT(nimaps); |
1411 | return xfs_bmbt_to_iomap(ip, iomap, imap: &imap, mapping_flags: flags, IOMAP_F_XATTR, sequence_cookie: seq); |
1412 | } |
1413 | |
1414 | const struct iomap_ops xfs_xattr_iomap_ops = { |
1415 | .iomap_begin = xfs_xattr_iomap_begin, |
1416 | }; |
1417 | |
1418 | int |
1419 | xfs_zero_range( |
1420 | struct xfs_inode *ip, |
1421 | loff_t pos, |
1422 | loff_t len, |
1423 | bool *did_zero) |
1424 | { |
1425 | struct inode *inode = VFS_I(ip); |
1426 | |
1427 | if (IS_DAX(inode)) |
1428 | return dax_zero_range(inode, pos, len, did_zero, |
1429 | ops: &xfs_dax_write_iomap_ops); |
1430 | return iomap_zero_range(inode, pos, len, did_zero, |
1431 | ops: &xfs_buffered_write_iomap_ops); |
1432 | } |
1433 | |
1434 | int |
1435 | xfs_truncate_page( |
1436 | struct xfs_inode *ip, |
1437 | loff_t pos, |
1438 | bool *did_zero) |
1439 | { |
1440 | struct inode *inode = VFS_I(ip); |
1441 | |
1442 | if (IS_DAX(inode)) |
1443 | return dax_truncate_page(inode, pos, did_zero, |
1444 | ops: &xfs_dax_write_iomap_ops); |
1445 | return iomap_truncate_page(inode, pos, did_zero, |
1446 | ops: &xfs_buffered_write_iomap_ops); |
1447 | } |
1448 | |