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