1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2011, Lawrence Livermore National Security, LLC.
23 * Copyright (c) 2015 by Chunwei Chen. All rights reserved.
24 */
25
26
27 #ifdef CONFIG_COMPAT
28 #include <linux/compat.h>
29 #endif
30 #include <linux/fs.h>
31 #include <linux/migrate.h>
32 #include <sys/file.h>
33 #include <sys/dmu_objset.h>
34 #include <sys/zfs_znode.h>
35 #include <sys/zfs_vfsops.h>
36 #include <sys/zfs_vnops.h>
37 #include <sys/zfs_project.h>
38 #if defined(HAVE_VFS_SET_PAGE_DIRTY_NOBUFFERS) || \
39 defined(HAVE_VFS_FILEMAP_DIRTY_FOLIO)
40 #include <linux/pagemap.h>
41 #endif
42 #include <linux/fadvise.h>
43 #ifdef HAVE_VFS_FILEMAP_DIRTY_FOLIO
44 #include <linux/writeback.h>
45 #endif
46
47 /*
48 * When using fallocate(2) to preallocate space, inflate the requested
49 * capacity check by 10% to account for the required metadata blocks.
50 */
51 static unsigned int zfs_fallocate_reserve_percent = 110;
52
53 static int
zpl_open(struct inode * ip,struct file * filp)54 zpl_open(struct inode *ip, struct file *filp)
55 {
56 cred_t *cr = CRED();
57 int error;
58 fstrans_cookie_t cookie;
59
60 error = generic_file_open(ip, filp);
61 if (error)
62 return (error);
63
64 crhold(cr);
65 cookie = spl_fstrans_mark();
66 error = -zfs_open(ip, filp->f_mode, filp->f_flags, cr);
67 spl_fstrans_unmark(cookie);
68 crfree(cr);
69 ASSERT3S(error, <=, 0);
70
71 return (error);
72 }
73
74 static int
zpl_release(struct inode * ip,struct file * filp)75 zpl_release(struct inode *ip, struct file *filp)
76 {
77 cred_t *cr = CRED();
78 int error;
79 fstrans_cookie_t cookie;
80
81 cookie = spl_fstrans_mark();
82 if (ITOZ(ip)->z_atime_dirty)
83 zfs_mark_inode_dirty(ip);
84
85 crhold(cr);
86 error = -zfs_close(ip, filp->f_flags, cr);
87 spl_fstrans_unmark(cookie);
88 crfree(cr);
89 ASSERT3S(error, <=, 0);
90
91 return (error);
92 }
93
94 static int
zpl_iterate(struct file * filp,struct dir_context * ctx)95 zpl_iterate(struct file *filp, struct dir_context *ctx)
96 {
97 cred_t *cr = CRED();
98 int error;
99 fstrans_cookie_t cookie;
100
101 crhold(cr);
102 cookie = spl_fstrans_mark();
103 error = -zfs_readdir(file_inode(filp), ctx, cr);
104 spl_fstrans_unmark(cookie);
105 crfree(cr);
106 ASSERT3S(error, <=, 0);
107
108 return (error);
109 }
110
111 static int
zpl_fsync(struct file * filp,loff_t start,loff_t end,int datasync)112 zpl_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
113 {
114 struct inode *inode = filp->f_mapping->host;
115 znode_t *zp = ITOZ(inode);
116 zfsvfs_t *zfsvfs = ITOZSB(inode);
117 cred_t *cr = CRED();
118 int error;
119 fstrans_cookie_t cookie;
120
121 /*
122 * The variables z_sync_writes_cnt and z_async_writes_cnt work in
123 * tandem so that sync writes can detect if there are any non-sync
124 * writes going on and vice-versa. The "vice-versa" part to this logic
125 * is located in zfs_putpage() where non-sync writes check if there are
126 * any ongoing sync writes. If any sync and non-sync writes overlap,
127 * we do a commit to complete the non-sync writes since the latter can
128 * potentially take several seconds to complete and thus block sync
129 * writes in the upcoming call to filemap_write_and_wait_range().
130 */
131 atomic_inc_32(&zp->z_sync_writes_cnt);
132 /*
133 * If the following check does not detect an overlapping non-sync write
134 * (say because it's just about to start), then it is guaranteed that
135 * the non-sync write will detect this sync write. This is because we
136 * always increment z_sync_writes_cnt / z_async_writes_cnt before doing
137 * the check on z_async_writes_cnt / z_sync_writes_cnt here and in
138 * zfs_putpage() respectively.
139 */
140 if (atomic_load_32(&zp->z_async_writes_cnt) > 0) {
141 if ((error = zpl_enter(zfsvfs, FTAG)) != 0) {
142 atomic_dec_32(&zp->z_sync_writes_cnt);
143 return (error);
144 }
145 zil_commit(zfsvfs->z_log, zp->z_id);
146 zpl_exit(zfsvfs, FTAG);
147 }
148
149 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
150
151 /*
152 * The sync write is not complete yet but we decrement
153 * z_sync_writes_cnt since zfs_fsync() increments and decrements
154 * it internally. If a non-sync write starts just after the decrement
155 * operation but before we call zfs_fsync(), it may not detect this
156 * overlapping sync write but it does not matter since we have already
157 * gone past filemap_write_and_wait_range() and we won't block due to
158 * the non-sync write.
159 */
160 atomic_dec_32(&zp->z_sync_writes_cnt);
161
162 if (error)
163 return (error);
164
165 crhold(cr);
166 cookie = spl_fstrans_mark();
167 error = -zfs_fsync(zp, datasync, cr);
168 spl_fstrans_unmark(cookie);
169 crfree(cr);
170 ASSERT3S(error, <=, 0);
171
172 return (error);
173 }
174
175 static inline int
zfs_io_flags(struct kiocb * kiocb)176 zfs_io_flags(struct kiocb *kiocb)
177 {
178 int flags = 0;
179
180 #if defined(IOCB_DSYNC)
181 if (kiocb->ki_flags & IOCB_DSYNC)
182 flags |= O_DSYNC;
183 #endif
184 #if defined(IOCB_SYNC)
185 if (kiocb->ki_flags & IOCB_SYNC)
186 flags |= O_SYNC;
187 #endif
188 #if defined(IOCB_APPEND)
189 if (kiocb->ki_flags & IOCB_APPEND)
190 flags |= O_APPEND;
191 #endif
192 #if defined(IOCB_DIRECT)
193 if (kiocb->ki_flags & IOCB_DIRECT)
194 flags |= O_DIRECT;
195 #endif
196 return (flags);
197 }
198
199 /*
200 * If relatime is enabled, call file_accessed() if zfs_relatime_need_update()
201 * is true. This is needed since datasets with inherited "relatime" property
202 * aren't necessarily mounted with the MNT_RELATIME flag (e.g. after
203 * `zfs set relatime=...`), which is what relatime test in VFS by
204 * relatime_need_update() is based on.
205 */
206 static inline void
zpl_file_accessed(struct file * filp)207 zpl_file_accessed(struct file *filp)
208 {
209 struct inode *ip = filp->f_mapping->host;
210
211 if (!IS_NOATIME(ip) && ITOZSB(ip)->z_relatime) {
212 if (zfs_relatime_need_update(ip))
213 file_accessed(filp);
214 } else {
215 file_accessed(filp);
216 }
217 }
218
219 /*
220 * When HAVE_VFS_IOV_ITER is defined the iov_iter structure supports
221 * iovecs, kvevs, bvecs and pipes, plus all the required interfaces to
222 * manipulate the iov_iter are available. In which case the full iov_iter
223 * can be attached to the uio and correctly handled in the lower layers.
224 * Otherwise, for older kernels extract the iovec and pass it instead.
225 */
226 static void
zpl_uio_init(zfs_uio_t * uio,struct kiocb * kiocb,struct iov_iter * to,loff_t pos,ssize_t count,size_t skip)227 zpl_uio_init(zfs_uio_t *uio, struct kiocb *kiocb, struct iov_iter *to,
228 loff_t pos, ssize_t count, size_t skip)
229 {
230 #if defined(HAVE_VFS_IOV_ITER)
231 zfs_uio_iov_iter_init(uio, to, pos, count, skip);
232 #else
233 zfs_uio_iovec_init(uio, zfs_uio_iter_iov(to), to->nr_segs, pos,
234 zfs_uio_iov_iter_type(to) & ITER_KVEC ?
235 UIO_SYSSPACE : UIO_USERSPACE,
236 count, skip);
237 #endif
238 }
239
240 static ssize_t
zpl_iter_read(struct kiocb * kiocb,struct iov_iter * to)241 zpl_iter_read(struct kiocb *kiocb, struct iov_iter *to)
242 {
243 cred_t *cr = CRED();
244 fstrans_cookie_t cookie;
245 struct file *filp = kiocb->ki_filp;
246 ssize_t count = iov_iter_count(to);
247 zfs_uio_t uio;
248
249 zpl_uio_init(&uio, kiocb, to, kiocb->ki_pos, count, 0);
250
251 crhold(cr);
252 cookie = spl_fstrans_mark();
253
254 ssize_t ret = -zfs_read(ITOZ(filp->f_mapping->host), &uio,
255 filp->f_flags | zfs_io_flags(kiocb), cr);
256
257 spl_fstrans_unmark(cookie);
258 crfree(cr);
259
260 if (ret < 0)
261 return (ret);
262
263 ssize_t read = count - uio.uio_resid;
264 kiocb->ki_pos += read;
265
266 zpl_file_accessed(filp);
267
268 return (read);
269 }
270
271 static inline ssize_t
zpl_generic_write_checks(struct kiocb * kiocb,struct iov_iter * from,size_t * countp)272 zpl_generic_write_checks(struct kiocb *kiocb, struct iov_iter *from,
273 size_t *countp)
274 {
275 ssize_t ret = generic_write_checks(kiocb, from);
276 if (ret <= 0)
277 return (ret);
278
279 *countp = ret;
280
281 return (0);
282 }
283
284 static ssize_t
zpl_iter_write(struct kiocb * kiocb,struct iov_iter * from)285 zpl_iter_write(struct kiocb *kiocb, struct iov_iter *from)
286 {
287 cred_t *cr = CRED();
288 fstrans_cookie_t cookie;
289 struct file *filp = kiocb->ki_filp;
290 struct inode *ip = filp->f_mapping->host;
291 zfs_uio_t uio;
292 size_t count = 0;
293 ssize_t ret;
294
295 ret = zpl_generic_write_checks(kiocb, from, &count);
296 if (ret)
297 return (ret);
298
299 zpl_uio_init(&uio, kiocb, from, kiocb->ki_pos, count, from->iov_offset);
300
301 crhold(cr);
302 cookie = spl_fstrans_mark();
303
304 ret = -zfs_write(ITOZ(ip), &uio,
305 filp->f_flags | zfs_io_flags(kiocb), cr);
306
307 spl_fstrans_unmark(cookie);
308 crfree(cr);
309
310 if (ret < 0)
311 return (ret);
312
313 ssize_t wrote = count - uio.uio_resid;
314 kiocb->ki_pos += wrote;
315
316 return (wrote);
317 }
318
319 static ssize_t
zpl_direct_IO_impl(void)320 zpl_direct_IO_impl(void)
321 {
322 /*
323 * All O_DIRECT requests should be handled by
324 * zpl_{iter/aio}_{write/read}(). There is no way kernel generic code
325 * should call the direct_IO address_space_operations function. We set
326 * this code path to be fatal if it is executed.
327 */
328 PANIC(0);
329 return (0);
330 }
331
332 #if defined(HAVE_VFS_DIRECT_IO_ITER)
333 static ssize_t
zpl_direct_IO(struct kiocb * kiocb,struct iov_iter * iter)334 zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter)
335 {
336 return (zpl_direct_IO_impl());
337 }
338 #elif defined(HAVE_VFS_DIRECT_IO_ITER_OFFSET)
339 static ssize_t
zpl_direct_IO(struct kiocb * kiocb,struct iov_iter * iter,loff_t pos)340 zpl_direct_IO(struct kiocb *kiocb, struct iov_iter *iter, loff_t pos)
341 {
342 return (zpl_direct_IO_impl());
343 }
344 #else
345 #error "Unknown Direct I/O interface"
346 #endif
347
348 static loff_t
zpl_llseek(struct file * filp,loff_t offset,int whence)349 zpl_llseek(struct file *filp, loff_t offset, int whence)
350 {
351 #if defined(SEEK_HOLE) && defined(SEEK_DATA)
352 fstrans_cookie_t cookie;
353
354 if (whence == SEEK_DATA || whence == SEEK_HOLE) {
355 struct inode *ip = filp->f_mapping->host;
356 loff_t maxbytes = ip->i_sb->s_maxbytes;
357 loff_t error;
358
359 spl_inode_lock_shared(ip);
360 cookie = spl_fstrans_mark();
361 error = -zfs_holey(ITOZ(ip), whence, &offset);
362 spl_fstrans_unmark(cookie);
363 if (error == 0)
364 error = lseek_execute(filp, ip, offset, maxbytes);
365 spl_inode_unlock_shared(ip);
366
367 return (error);
368 }
369 #endif /* SEEK_HOLE && SEEK_DATA */
370
371 return (generic_file_llseek(filp, offset, whence));
372 }
373
374 /*
375 * It's worth taking a moment to describe how mmap is implemented
376 * for zfs because it differs considerably from other Linux filesystems.
377 * However, this issue is handled the same way under OpenSolaris.
378 *
379 * The issue is that by design zfs bypasses the Linux page cache and
380 * leaves all caching up to the ARC. This has been shown to work
381 * well for the common read(2)/write(2) case. However, mmap(2)
382 * is problem because it relies on being tightly integrated with the
383 * page cache. To handle this we cache mmap'ed files twice, once in
384 * the ARC and a second time in the page cache. The code is careful
385 * to keep both copies synchronized.
386 *
387 * When a file with an mmap'ed region is written to using write(2)
388 * both the data in the ARC and existing pages in the page cache
389 * are updated. For a read(2) data will be read first from the page
390 * cache then the ARC if needed. Neither a write(2) or read(2) will
391 * will ever result in new pages being added to the page cache.
392 *
393 * New pages are added to the page cache only via .readpage() which
394 * is called when the vfs needs to read a page off disk to back the
395 * virtual memory region. These pages may be modified without
396 * notifying the ARC and will be written out periodically via
397 * .writepage(). This will occur due to either a sync or the usual
398 * page aging behavior. Note because a read(2) of a mmap'ed file
399 * will always check the page cache first even when the ARC is out
400 * of date correct data will still be returned.
401 *
402 * While this implementation ensures correct behavior it does have
403 * have some drawbacks. The most obvious of which is that it
404 * increases the required memory footprint when access mmap'ed
405 * files. It also adds additional complexity to the code keeping
406 * both caches synchronized.
407 *
408 * Longer term it may be possible to cleanly resolve this wart by
409 * mapping page cache pages directly on to the ARC buffers. The
410 * Linux address space operations are flexible enough to allow
411 * selection of which pages back a particular index. The trick
412 * would be working out the details of which subsystem is in
413 * charge, the ARC, the page cache, or both. It may also prove
414 * helpful to move the ARC buffers to a scatter-gather lists
415 * rather than a vmalloc'ed region.
416 */
417 static int
zpl_mmap(struct file * filp,struct vm_area_struct * vma)418 zpl_mmap(struct file *filp, struct vm_area_struct *vma)
419 {
420 struct inode *ip = filp->f_mapping->host;
421 int error;
422 fstrans_cookie_t cookie;
423
424 cookie = spl_fstrans_mark();
425 error = -zfs_map(ip, vma->vm_pgoff, (caddr_t *)vma->vm_start,
426 (size_t)(vma->vm_end - vma->vm_start), vma->vm_flags);
427 spl_fstrans_unmark(cookie);
428
429 if (error)
430 return (error);
431
432 error = generic_file_mmap(filp, vma);
433 if (error)
434 return (error);
435
436 return (error);
437 }
438
439 /*
440 * Populate a page with data for the Linux page cache. This function is
441 * only used to support mmap(2). There will be an identical copy of the
442 * data in the ARC which is kept up to date via .write() and .writepage().
443 */
444 static inline int
zpl_readpage_common(struct page * pp)445 zpl_readpage_common(struct page *pp)
446 {
447 fstrans_cookie_t cookie;
448
449 ASSERT(PageLocked(pp));
450
451 cookie = spl_fstrans_mark();
452 int error = -zfs_getpage(pp->mapping->host, pp);
453 spl_fstrans_unmark(cookie);
454
455 unlock_page(pp);
456
457 return (error);
458 }
459
460 #ifdef HAVE_VFS_READ_FOLIO
461 static int
zpl_read_folio(struct file * filp,struct folio * folio)462 zpl_read_folio(struct file *filp, struct folio *folio)
463 {
464 return (zpl_readpage_common(&folio->page));
465 }
466 #else
467 static int
zpl_readpage(struct file * filp,struct page * pp)468 zpl_readpage(struct file *filp, struct page *pp)
469 {
470 return (zpl_readpage_common(pp));
471 }
472 #endif
473
474 static int
zpl_readpage_filler(void * data,struct page * pp)475 zpl_readpage_filler(void *data, struct page *pp)
476 {
477 return (zpl_readpage_common(pp));
478 }
479
480 /*
481 * Populate a set of pages with data for the Linux page cache. This
482 * function will only be called for read ahead and never for demand
483 * paging. For simplicity, the code relies on read_cache_pages() to
484 * correctly lock each page for IO and call zpl_readpage().
485 */
486 #ifdef HAVE_VFS_READPAGES
487 static int
zpl_readpages(struct file * filp,struct address_space * mapping,struct list_head * pages,unsigned nr_pages)488 zpl_readpages(struct file *filp, struct address_space *mapping,
489 struct list_head *pages, unsigned nr_pages)
490 {
491 return (read_cache_pages(mapping, pages, zpl_readpage_filler, NULL));
492 }
493 #else
494 static void
zpl_readahead(struct readahead_control * ractl)495 zpl_readahead(struct readahead_control *ractl)
496 {
497 struct page *page;
498
499 while ((page = readahead_page(ractl)) != NULL) {
500 int ret;
501
502 ret = zpl_readpage_filler(NULL, page);
503 put_page(page);
504 if (ret)
505 break;
506 }
507 }
508 #endif
509
510 static int
zpl_putpage(struct page * pp,struct writeback_control * wbc,void * data)511 zpl_putpage(struct page *pp, struct writeback_control *wbc, void *data)
512 {
513 boolean_t *for_sync = data;
514 fstrans_cookie_t cookie;
515 int ret;
516
517 ASSERT(PageLocked(pp));
518 ASSERT(!PageWriteback(pp));
519
520 cookie = spl_fstrans_mark();
521 ret = zfs_putpage(pp->mapping->host, pp, wbc, *for_sync);
522 spl_fstrans_unmark(cookie);
523
524 return (ret);
525 }
526
527 #ifdef HAVE_WRITEPAGE_T_FOLIO
528 static int
zpl_putfolio(struct folio * pp,struct writeback_control * wbc,void * data)529 zpl_putfolio(struct folio *pp, struct writeback_control *wbc, void *data)
530 {
531 return (zpl_putpage(&pp->page, wbc, data));
532 }
533 #endif
534
535 static inline int
zpl_write_cache_pages(struct address_space * mapping,struct writeback_control * wbc,void * data)536 zpl_write_cache_pages(struct address_space *mapping,
537 struct writeback_control *wbc, void *data)
538 {
539 int result;
540
541 #ifdef HAVE_WRITEPAGE_T_FOLIO
542 result = write_cache_pages(mapping, wbc, zpl_putfolio, data);
543 #else
544 result = write_cache_pages(mapping, wbc, zpl_putpage, data);
545 #endif
546 return (result);
547 }
548
549 static int
zpl_writepages(struct address_space * mapping,struct writeback_control * wbc)550 zpl_writepages(struct address_space *mapping, struct writeback_control *wbc)
551 {
552 znode_t *zp = ITOZ(mapping->host);
553 zfsvfs_t *zfsvfs = ITOZSB(mapping->host);
554 enum writeback_sync_modes sync_mode;
555 int result;
556
557 if ((result = zpl_enter(zfsvfs, FTAG)) != 0)
558 return (result);
559 if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
560 wbc->sync_mode = WB_SYNC_ALL;
561 zpl_exit(zfsvfs, FTAG);
562 sync_mode = wbc->sync_mode;
563
564 /*
565 * We don't want to run write_cache_pages() in SYNC mode here, because
566 * that would make putpage() wait for a single page to be committed to
567 * disk every single time, resulting in atrocious performance. Instead
568 * we run it once in non-SYNC mode so that the ZIL gets all the data,
569 * and then we commit it all in one go.
570 */
571 boolean_t for_sync = (sync_mode == WB_SYNC_ALL);
572 wbc->sync_mode = WB_SYNC_NONE;
573 result = zpl_write_cache_pages(mapping, wbc, &for_sync);
574 if (sync_mode != wbc->sync_mode) {
575 if ((result = zpl_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
576 return (result);
577 if (zfsvfs->z_log != NULL)
578 zil_commit(zfsvfs->z_log, zp->z_id);
579 zpl_exit(zfsvfs, FTAG);
580
581 /*
582 * We need to call write_cache_pages() again (we can't just
583 * return after the commit) because the previous call in
584 * non-SYNC mode does not guarantee that we got all the dirty
585 * pages (see the implementation of write_cache_pages() for
586 * details). That being said, this is a no-op in most cases.
587 */
588 wbc->sync_mode = sync_mode;
589 result = zpl_write_cache_pages(mapping, wbc, &for_sync);
590 }
591 return (result);
592 }
593
594 /*
595 * Write out dirty pages to the ARC, this function is only required to
596 * support mmap(2). Mapped pages may be dirtied by memory operations
597 * which never call .write(). These dirty pages are kept in sync with
598 * the ARC buffers via this hook.
599 */
600 static int
zpl_writepage(struct page * pp,struct writeback_control * wbc)601 zpl_writepage(struct page *pp, struct writeback_control *wbc)
602 {
603 if (ITOZSB(pp->mapping->host)->z_os->os_sync == ZFS_SYNC_ALWAYS)
604 wbc->sync_mode = WB_SYNC_ALL;
605
606 boolean_t for_sync = (wbc->sync_mode == WB_SYNC_ALL);
607
608 return (zpl_putpage(pp, wbc, &for_sync));
609 }
610
611 /*
612 * The flag combination which matches the behavior of zfs_space() is
613 * FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE. The FALLOC_FL_PUNCH_HOLE
614 * flag was introduced in the 2.6.38 kernel.
615 *
616 * The original mode=0 (allocate space) behavior can be reasonably emulated
617 * by checking if enough space exists and creating a sparse file, as real
618 * persistent space reservation is not possible due to COW, snapshots, etc.
619 */
620 static long
zpl_fallocate_common(struct inode * ip,int mode,loff_t offset,loff_t len)621 zpl_fallocate_common(struct inode *ip, int mode, loff_t offset, loff_t len)
622 {
623 cred_t *cr = CRED();
624 loff_t olen;
625 fstrans_cookie_t cookie;
626 int error = 0;
627
628 int test_mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE;
629
630 if ((mode & ~(FALLOC_FL_KEEP_SIZE | test_mode)) != 0)
631 return (-EOPNOTSUPP);
632
633 if (offset < 0 || len <= 0)
634 return (-EINVAL);
635
636 spl_inode_lock(ip);
637 olen = i_size_read(ip);
638
639 crhold(cr);
640 cookie = spl_fstrans_mark();
641 if (mode & (test_mode)) {
642 flock64_t bf;
643
644 if (mode & FALLOC_FL_KEEP_SIZE) {
645 if (offset > olen)
646 goto out_unmark;
647
648 if (offset + len > olen)
649 len = olen - offset;
650 }
651 bf.l_type = F_WRLCK;
652 bf.l_whence = SEEK_SET;
653 bf.l_start = offset;
654 bf.l_len = len;
655 bf.l_pid = 0;
656
657 error = -zfs_space(ITOZ(ip), F_FREESP, &bf, O_RDWR, offset, cr);
658 } else if ((mode & ~FALLOC_FL_KEEP_SIZE) == 0) {
659 unsigned int percent = zfs_fallocate_reserve_percent;
660 struct kstatfs statfs;
661
662 /* Legacy mode, disable fallocate compatibility. */
663 if (percent == 0) {
664 error = -EOPNOTSUPP;
665 goto out_unmark;
666 }
667
668 /*
669 * Use zfs_statvfs() instead of dmu_objset_space() since it
670 * also checks project quota limits, which are relevant here.
671 */
672 error = zfs_statvfs(ip, &statfs);
673 if (error)
674 goto out_unmark;
675
676 /*
677 * Shrink available space a bit to account for overhead/races.
678 * We know the product previously fit into availbytes from
679 * dmu_objset_space(), so the smaller product will also fit.
680 */
681 if (len > statfs.f_bavail * (statfs.f_bsize * 100 / percent)) {
682 error = -ENOSPC;
683 goto out_unmark;
684 }
685 if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > olen)
686 error = zfs_freesp(ITOZ(ip), offset + len, 0, 0, FALSE);
687 }
688 out_unmark:
689 spl_fstrans_unmark(cookie);
690 spl_inode_unlock(ip);
691
692 crfree(cr);
693
694 return (error);
695 }
696
697 static long
zpl_fallocate(struct file * filp,int mode,loff_t offset,loff_t len)698 zpl_fallocate(struct file *filp, int mode, loff_t offset, loff_t len)
699 {
700 return zpl_fallocate_common(file_inode(filp),
701 mode, offset, len);
702 }
703
704 static int
zpl_ioctl_getversion(struct file * filp,void __user * arg)705 zpl_ioctl_getversion(struct file *filp, void __user *arg)
706 {
707 uint32_t generation = file_inode(filp)->i_generation;
708
709 return (copy_to_user(arg, &generation, sizeof (generation)));
710 }
711
712 static int
zpl_fadvise(struct file * filp,loff_t offset,loff_t len,int advice)713 zpl_fadvise(struct file *filp, loff_t offset, loff_t len, int advice)
714 {
715 struct inode *ip = file_inode(filp);
716 znode_t *zp = ITOZ(ip);
717 zfsvfs_t *zfsvfs = ITOZSB(ip);
718 objset_t *os = zfsvfs->z_os;
719 int error = 0;
720
721 if (S_ISFIFO(ip->i_mode))
722 return (-ESPIPE);
723
724 if (offset < 0 || len < 0)
725 return (-EINVAL);
726
727 if ((error = zpl_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
728 return (error);
729
730 switch (advice) {
731 case POSIX_FADV_SEQUENTIAL:
732 case POSIX_FADV_WILLNEED:
733 #ifdef HAVE_GENERIC_FADVISE
734 if (zn_has_cached_data(zp, offset, offset + len - 1))
735 error = generic_fadvise(filp, offset, len, advice);
736 #endif
737 /*
738 * Pass on the caller's size directly, but note that
739 * dmu_prefetch_max will effectively cap it. If there
740 * really is a larger sequential access pattern, perhaps
741 * dmu_zfetch will detect it.
742 */
743 if (len == 0)
744 len = i_size_read(ip) - offset;
745
746 dmu_prefetch(os, zp->z_id, 0, offset, len,
747 ZIO_PRIORITY_ASYNC_READ);
748 break;
749 case POSIX_FADV_NORMAL:
750 case POSIX_FADV_RANDOM:
751 case POSIX_FADV_DONTNEED:
752 case POSIX_FADV_NOREUSE:
753 /* ignored for now */
754 break;
755 default:
756 error = -EINVAL;
757 break;
758 }
759
760 zfs_exit(zfsvfs, FTAG);
761
762 return (error);
763 }
764
765 #define ZFS_FL_USER_VISIBLE (FS_FL_USER_VISIBLE | ZFS_PROJINHERIT_FL)
766 #define ZFS_FL_USER_MODIFIABLE (FS_FL_USER_MODIFIABLE | ZFS_PROJINHERIT_FL)
767
768 static uint32_t
__zpl_ioctl_getflags(struct inode * ip)769 __zpl_ioctl_getflags(struct inode *ip)
770 {
771 uint64_t zfs_flags = ITOZ(ip)->z_pflags;
772 uint32_t ioctl_flags = 0;
773
774 if (zfs_flags & ZFS_IMMUTABLE)
775 ioctl_flags |= FS_IMMUTABLE_FL;
776
777 if (zfs_flags & ZFS_APPENDONLY)
778 ioctl_flags |= FS_APPEND_FL;
779
780 if (zfs_flags & ZFS_NODUMP)
781 ioctl_flags |= FS_NODUMP_FL;
782
783 if (zfs_flags & ZFS_PROJINHERIT)
784 ioctl_flags |= ZFS_PROJINHERIT_FL;
785
786 return (ioctl_flags & ZFS_FL_USER_VISIBLE);
787 }
788
789 /*
790 * Map zfs file z_pflags (xvattr_t) to linux file attributes. Only file
791 * attributes common to both Linux and Solaris are mapped.
792 */
793 static int
zpl_ioctl_getflags(struct file * filp,void __user * arg)794 zpl_ioctl_getflags(struct file *filp, void __user *arg)
795 {
796 uint32_t flags;
797 int err;
798
799 flags = __zpl_ioctl_getflags(file_inode(filp));
800 err = copy_to_user(arg, &flags, sizeof (flags));
801
802 return (err);
803 }
804
805 /*
806 * fchange() is a helper macro to detect if we have been asked to change a
807 * flag. This is ugly, but the requirement that we do this is a consequence of
808 * how the Linux file attribute interface was designed. Another consequence is
809 * that concurrent modification of files suffers from a TOCTOU race. Neither
810 * are things we can fix without modifying the kernel-userland interface, which
811 * is outside of our jurisdiction.
812 */
813
814 #define fchange(f0, f1, b0, b1) (!((f0) & (b0)) != !((f1) & (b1)))
815
816 static int
__zpl_ioctl_setflags(struct inode * ip,uint32_t ioctl_flags,xvattr_t * xva)817 __zpl_ioctl_setflags(struct inode *ip, uint32_t ioctl_flags, xvattr_t *xva)
818 {
819 uint64_t zfs_flags = ITOZ(ip)->z_pflags;
820 xoptattr_t *xoap;
821
822 if (ioctl_flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | FS_NODUMP_FL |
823 ZFS_PROJINHERIT_FL))
824 return (-EOPNOTSUPP);
825
826 if (ioctl_flags & ~ZFS_FL_USER_MODIFIABLE)
827 return (-EACCES);
828
829 if ((fchange(ioctl_flags, zfs_flags, FS_IMMUTABLE_FL, ZFS_IMMUTABLE) ||
830 fchange(ioctl_flags, zfs_flags, FS_APPEND_FL, ZFS_APPENDONLY)) &&
831 !capable(CAP_LINUX_IMMUTABLE))
832 return (-EPERM);
833
834 if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
835 return (-EACCES);
836
837 xva_init(xva);
838 xoap = xva_getxoptattr(xva);
839
840 #define FLAG_CHANGE(iflag, zflag, xflag, xfield) do { \
841 if (((ioctl_flags & (iflag)) && !(zfs_flags & (zflag))) || \
842 ((zfs_flags & (zflag)) && !(ioctl_flags & (iflag)))) { \
843 XVA_SET_REQ(xva, (xflag)); \
844 (xfield) = ((ioctl_flags & (iflag)) != 0); \
845 } \
846 } while (0)
847
848 FLAG_CHANGE(FS_IMMUTABLE_FL, ZFS_IMMUTABLE, XAT_IMMUTABLE,
849 xoap->xoa_immutable);
850 FLAG_CHANGE(FS_APPEND_FL, ZFS_APPENDONLY, XAT_APPENDONLY,
851 xoap->xoa_appendonly);
852 FLAG_CHANGE(FS_NODUMP_FL, ZFS_NODUMP, XAT_NODUMP,
853 xoap->xoa_nodump);
854 FLAG_CHANGE(ZFS_PROJINHERIT_FL, ZFS_PROJINHERIT, XAT_PROJINHERIT,
855 xoap->xoa_projinherit);
856
857 #undef FLAG_CHANGE
858
859 return (0);
860 }
861
862 static int
zpl_ioctl_setflags(struct file * filp,void __user * arg)863 zpl_ioctl_setflags(struct file *filp, void __user *arg)
864 {
865 struct inode *ip = file_inode(filp);
866 uint32_t flags;
867 cred_t *cr = CRED();
868 xvattr_t xva;
869 int err;
870 fstrans_cookie_t cookie;
871
872 if (copy_from_user(&flags, arg, sizeof (flags)))
873 return (-EFAULT);
874
875 err = __zpl_ioctl_setflags(ip, flags, &xva);
876 if (err)
877 return (err);
878
879 crhold(cr);
880 cookie = spl_fstrans_mark();
881 err = -zfs_setattr(ITOZ(ip), (vattr_t *)&xva, 0, cr, zfs_init_idmap);
882 spl_fstrans_unmark(cookie);
883 crfree(cr);
884
885 return (err);
886 }
887
888 static int
zpl_ioctl_getxattr(struct file * filp,void __user * arg)889 zpl_ioctl_getxattr(struct file *filp, void __user *arg)
890 {
891 zfsxattr_t fsx = { 0 };
892 struct inode *ip = file_inode(filp);
893 int err;
894
895 fsx.fsx_xflags = __zpl_ioctl_getflags(ip);
896 fsx.fsx_projid = ITOZ(ip)->z_projid;
897 err = copy_to_user(arg, &fsx, sizeof (fsx));
898
899 return (err);
900 }
901
902 static int
zpl_ioctl_setxattr(struct file * filp,void __user * arg)903 zpl_ioctl_setxattr(struct file *filp, void __user *arg)
904 {
905 struct inode *ip = file_inode(filp);
906 zfsxattr_t fsx;
907 cred_t *cr = CRED();
908 xvattr_t xva;
909 xoptattr_t *xoap;
910 int err;
911 fstrans_cookie_t cookie;
912
913 if (copy_from_user(&fsx, arg, sizeof (fsx)))
914 return (-EFAULT);
915
916 if (!zpl_is_valid_projid(fsx.fsx_projid))
917 return (-EINVAL);
918
919 err = __zpl_ioctl_setflags(ip, fsx.fsx_xflags, &xva);
920 if (err)
921 return (err);
922
923 xoap = xva_getxoptattr(&xva);
924 XVA_SET_REQ(&xva, XAT_PROJID);
925 xoap->xoa_projid = fsx.fsx_projid;
926
927 crhold(cr);
928 cookie = spl_fstrans_mark();
929 err = -zfs_setattr(ITOZ(ip), (vattr_t *)&xva, 0, cr, zfs_init_idmap);
930 spl_fstrans_unmark(cookie);
931 crfree(cr);
932
933 return (err);
934 }
935
936 /*
937 * Expose Additional File Level Attributes of ZFS.
938 */
939 static int
zpl_ioctl_getdosflags(struct file * filp,void __user * arg)940 zpl_ioctl_getdosflags(struct file *filp, void __user *arg)
941 {
942 struct inode *ip = file_inode(filp);
943 uint64_t dosflags = ITOZ(ip)->z_pflags;
944 dosflags &= ZFS_DOS_FL_USER_VISIBLE;
945 int err = copy_to_user(arg, &dosflags, sizeof (dosflags));
946
947 return (err);
948 }
949
950 static int
__zpl_ioctl_setdosflags(struct inode * ip,uint64_t ioctl_flags,xvattr_t * xva)951 __zpl_ioctl_setdosflags(struct inode *ip, uint64_t ioctl_flags, xvattr_t *xva)
952 {
953 uint64_t zfs_flags = ITOZ(ip)->z_pflags;
954 xoptattr_t *xoap;
955
956 if (ioctl_flags & (~ZFS_DOS_FL_USER_VISIBLE))
957 return (-EOPNOTSUPP);
958
959 if ((fchange(ioctl_flags, zfs_flags, ZFS_IMMUTABLE, ZFS_IMMUTABLE) ||
960 fchange(ioctl_flags, zfs_flags, ZFS_APPENDONLY, ZFS_APPENDONLY)) &&
961 !capable(CAP_LINUX_IMMUTABLE))
962 return (-EPERM);
963
964 if (!zpl_inode_owner_or_capable(zfs_init_idmap, ip))
965 return (-EACCES);
966
967 xva_init(xva);
968 xoap = xva_getxoptattr(xva);
969
970 #define FLAG_CHANGE(iflag, xflag, xfield) do { \
971 if (((ioctl_flags & (iflag)) && !(zfs_flags & (iflag))) || \
972 ((zfs_flags & (iflag)) && !(ioctl_flags & (iflag)))) { \
973 XVA_SET_REQ(xva, (xflag)); \
974 (xfield) = ((ioctl_flags & (iflag)) != 0); \
975 } \
976 } while (0)
977
978 FLAG_CHANGE(ZFS_IMMUTABLE, XAT_IMMUTABLE, xoap->xoa_immutable);
979 FLAG_CHANGE(ZFS_APPENDONLY, XAT_APPENDONLY, xoap->xoa_appendonly);
980 FLAG_CHANGE(ZFS_NODUMP, XAT_NODUMP, xoap->xoa_nodump);
981 FLAG_CHANGE(ZFS_READONLY, XAT_READONLY, xoap->xoa_readonly);
982 FLAG_CHANGE(ZFS_HIDDEN, XAT_HIDDEN, xoap->xoa_hidden);
983 FLAG_CHANGE(ZFS_SYSTEM, XAT_SYSTEM, xoap->xoa_system);
984 FLAG_CHANGE(ZFS_ARCHIVE, XAT_ARCHIVE, xoap->xoa_archive);
985 FLAG_CHANGE(ZFS_NOUNLINK, XAT_NOUNLINK, xoap->xoa_nounlink);
986 FLAG_CHANGE(ZFS_REPARSE, XAT_REPARSE, xoap->xoa_reparse);
987 FLAG_CHANGE(ZFS_OFFLINE, XAT_OFFLINE, xoap->xoa_offline);
988 FLAG_CHANGE(ZFS_SPARSE, XAT_SPARSE, xoap->xoa_sparse);
989
990 #undef FLAG_CHANGE
991
992 return (0);
993 }
994
995 /*
996 * Set Additional File Level Attributes of ZFS.
997 */
998 static int
zpl_ioctl_setdosflags(struct file * filp,void __user * arg)999 zpl_ioctl_setdosflags(struct file *filp, void __user *arg)
1000 {
1001 struct inode *ip = file_inode(filp);
1002 uint64_t dosflags;
1003 cred_t *cr = CRED();
1004 xvattr_t xva;
1005 int err;
1006 fstrans_cookie_t cookie;
1007
1008 if (copy_from_user(&dosflags, arg, sizeof (dosflags)))
1009 return (-EFAULT);
1010
1011 err = __zpl_ioctl_setdosflags(ip, dosflags, &xva);
1012 if (err)
1013 return (err);
1014
1015 crhold(cr);
1016 cookie = spl_fstrans_mark();
1017 err = -zfs_setattr(ITOZ(ip), (vattr_t *)&xva, 0, cr, zfs_init_idmap);
1018 spl_fstrans_unmark(cookie);
1019 crfree(cr);
1020
1021 return (err);
1022 }
1023
1024 static long
zpl_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)1025 zpl_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1026 {
1027 switch (cmd) {
1028 case FS_IOC_GETVERSION:
1029 return (zpl_ioctl_getversion(filp, (void *)arg));
1030 case FS_IOC_GETFLAGS:
1031 return (zpl_ioctl_getflags(filp, (void *)arg));
1032 case FS_IOC_SETFLAGS:
1033 return (zpl_ioctl_setflags(filp, (void *)arg));
1034 case ZFS_IOC_FSGETXATTR:
1035 return (zpl_ioctl_getxattr(filp, (void *)arg));
1036 case ZFS_IOC_FSSETXATTR:
1037 return (zpl_ioctl_setxattr(filp, (void *)arg));
1038 case ZFS_IOC_GETDOSFLAGS:
1039 return (zpl_ioctl_getdosflags(filp, (void *)arg));
1040 case ZFS_IOC_SETDOSFLAGS:
1041 return (zpl_ioctl_setdosflags(filp, (void *)arg));
1042 case ZFS_IOC_COMPAT_FICLONE:
1043 return (zpl_ioctl_ficlone(filp, (void *)arg));
1044 case ZFS_IOC_COMPAT_FICLONERANGE:
1045 return (zpl_ioctl_ficlonerange(filp, (void *)arg));
1046 case ZFS_IOC_COMPAT_FIDEDUPERANGE:
1047 return (zpl_ioctl_fideduperange(filp, (void *)arg));
1048 default:
1049 return (-ENOTTY);
1050 }
1051 }
1052
1053 #ifdef CONFIG_COMPAT
1054 static long
zpl_compat_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)1055 zpl_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1056 {
1057 switch (cmd) {
1058 case FS_IOC32_GETVERSION:
1059 cmd = FS_IOC_GETVERSION;
1060 break;
1061 case FS_IOC32_GETFLAGS:
1062 cmd = FS_IOC_GETFLAGS;
1063 break;
1064 case FS_IOC32_SETFLAGS:
1065 cmd = FS_IOC_SETFLAGS;
1066 break;
1067 default:
1068 return (-ENOTTY);
1069 }
1070 return (zpl_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)));
1071 }
1072 #endif /* CONFIG_COMPAT */
1073
1074 const struct address_space_operations zpl_address_space_operations = {
1075 #ifdef HAVE_VFS_READPAGES
1076 .readpages = zpl_readpages,
1077 #else
1078 .readahead = zpl_readahead,
1079 #endif
1080 #ifdef HAVE_VFS_READ_FOLIO
1081 .read_folio = zpl_read_folio,
1082 #else
1083 .readpage = zpl_readpage,
1084 #endif
1085 .writepage = zpl_writepage,
1086 .writepages = zpl_writepages,
1087 .direct_IO = zpl_direct_IO,
1088 #ifdef HAVE_VFS_SET_PAGE_DIRTY_NOBUFFERS
1089 .set_page_dirty = __set_page_dirty_nobuffers,
1090 #endif
1091 #ifdef HAVE_VFS_FILEMAP_DIRTY_FOLIO
1092 .dirty_folio = filemap_dirty_folio,
1093 #endif
1094 #ifdef HAVE_VFS_MIGRATE_FOLIO
1095 .migrate_folio = migrate_folio,
1096 #else
1097 .migratepage = migrate_page,
1098 #endif
1099 };
1100
1101 const struct file_operations zpl_file_operations = {
1102 .open = zpl_open,
1103 .release = zpl_release,
1104 .llseek = zpl_llseek,
1105 .read_iter = zpl_iter_read,
1106 .write_iter = zpl_iter_write,
1107 #ifdef HAVE_VFS_IOV_ITER
1108 #ifdef HAVE_COPY_SPLICE_READ
1109 .splice_read = copy_splice_read,
1110 #else
1111 .splice_read = generic_file_splice_read,
1112 #endif
1113 .splice_write = iter_file_splice_write,
1114 #endif
1115 .mmap = zpl_mmap,
1116 .fsync = zpl_fsync,
1117 .fallocate = zpl_fallocate,
1118 .copy_file_range = zpl_copy_file_range,
1119 #ifdef HAVE_VFS_CLONE_FILE_RANGE
1120 .clone_file_range = zpl_clone_file_range,
1121 #endif
1122 #ifdef HAVE_VFS_REMAP_FILE_RANGE
1123 .remap_file_range = zpl_remap_file_range,
1124 #endif
1125 #ifdef HAVE_VFS_DEDUPE_FILE_RANGE
1126 .dedupe_file_range = zpl_dedupe_file_range,
1127 #endif
1128 .fadvise = zpl_fadvise,
1129 .unlocked_ioctl = zpl_ioctl,
1130 #ifdef CONFIG_COMPAT
1131 .compat_ioctl = zpl_compat_ioctl,
1132 #endif
1133 };
1134
1135 const struct file_operations zpl_dir_file_operations = {
1136 .llseek = generic_file_llseek,
1137 .read = generic_read_dir,
1138 .iterate_shared = zpl_iterate,
1139 .fsync = zpl_fsync,
1140 .unlocked_ioctl = zpl_ioctl,
1141 #ifdef CONFIG_COMPAT
1142 .compat_ioctl = zpl_compat_ioctl,
1143 #endif
1144 };
1145
1146 /* CSTYLED */
1147 module_param(zfs_fallocate_reserve_percent, uint, 0644);
1148 MODULE_PARM_DESC(zfs_fallocate_reserve_percent,
1149 "Percentage of length to use for the available capacity check");
1150