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21#include <linux/module.h>
22#include <linux/time.h>
23#include <linux/errno.h>
24#include <linux/stat.h>
25#include <linux/fcntl.h>
26#include <linux/string.h>
27#include <linux/kernel.h>
28#include <linux/slab.h>
29#include <linux/mm.h>
30#include <linux/sunrpc/clnt.h>
31#include <linux/nfs_fs.h>
32#include <linux/nfs_mount.h>
33#include <linux/pagemap.h>
34#include <linux/pagevec.h>
35#include <linux/namei.h>
36#include <linux/mount.h>
37#include <linux/swap.h>
38#include <linux/sched.h>
39#include <linux/kmemleak.h>
40#include <linux/xattr.h>
41
42#include "delegation.h"
43#include "iostat.h"
44#include "internal.h"
45#include "fscache.h"
46
47#include "nfstrace.h"
48
49
50
51static int nfs_opendir(struct inode *, struct file *);
52static int nfs_closedir(struct inode *, struct file *);
53static int nfs_readdir(struct file *, struct dir_context *);
54static int nfs_fsync_dir(struct file *, loff_t, loff_t, int);
55static loff_t nfs_llseek_dir(struct file *, loff_t, int);
56static void nfs_readdir_clear_array(struct page*);
57
58const struct file_operations nfs_dir_operations = {
59 .llseek = nfs_llseek_dir,
60 .read = generic_read_dir,
61 .iterate_shared = nfs_readdir,
62 .open = nfs_opendir,
63 .release = nfs_closedir,
64 .fsync = nfs_fsync_dir,
65};
66
67const struct address_space_operations nfs_dir_aops = {
68 .freepage = nfs_readdir_clear_array,
69};
70
71static struct nfs_open_dir_context *alloc_nfs_open_dir_context(struct inode *dir)
72{
73 struct nfs_inode *nfsi = NFS_I(dir);
74 struct nfs_open_dir_context *ctx;
75 ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
76 if (ctx != NULL) {
77 ctx->duped = 0;
78 ctx->attr_gencount = nfsi->attr_gencount;
79 ctx->dir_cookie = 0;
80 ctx->dup_cookie = 0;
81 spin_lock(&dir->i_lock);
82 if (list_empty(&nfsi->open_files) &&
83 (nfsi->cache_validity & NFS_INO_DATA_INVAL_DEFER))
84 nfs_set_cache_invalid(dir,
85 NFS_INO_INVALID_DATA |
86 NFS_INO_REVAL_FORCED);
87 list_add(&ctx->list, &nfsi->open_files);
88 spin_unlock(&dir->i_lock);
89 return ctx;
90 }
91 return ERR_PTR(-ENOMEM);
92}
93
94static void put_nfs_open_dir_context(struct inode *dir, struct nfs_open_dir_context *ctx)
95{
96 spin_lock(&dir->i_lock);
97 list_del(&ctx->list);
98 spin_unlock(&dir->i_lock);
99 kfree(ctx);
100}
101
102
103
104
105static int
106nfs_opendir(struct inode *inode, struct file *filp)
107{
108 int res = 0;
109 struct nfs_open_dir_context *ctx;
110
111 dfprintk(FILE, "NFS: open dir(%pD2)\n", filp);
112
113 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
114
115 ctx = alloc_nfs_open_dir_context(inode);
116 if (IS_ERR(ctx)) {
117 res = PTR_ERR(ctx);
118 goto out;
119 }
120 filp->private_data = ctx;
121out:
122 return res;
123}
124
125static int
126nfs_closedir(struct inode *inode, struct file *filp)
127{
128 put_nfs_open_dir_context(file_inode(filp), filp->private_data);
129 return 0;
130}
131
132struct nfs_cache_array_entry {
133 u64 cookie;
134 u64 ino;
135 const char *name;
136 unsigned int name_len;
137 unsigned char d_type;
138};
139
140struct nfs_cache_array {
141 u64 last_cookie;
142 unsigned int size;
143 unsigned char page_full : 1,
144 page_is_eof : 1,
145 cookies_are_ordered : 1;
146 struct nfs_cache_array_entry array[];
147};
148
149struct nfs_readdir_descriptor {
150 struct file *file;
151 struct page *page;
152 struct dir_context *ctx;
153 pgoff_t page_index;
154 u64 dir_cookie;
155 u64 last_cookie;
156 u64 dup_cookie;
157 loff_t current_index;
158 loff_t prev_index;
159
160 __be32 verf[NFS_DIR_VERIFIER_SIZE];
161 unsigned long dir_verifier;
162 unsigned long timestamp;
163 unsigned long gencount;
164 unsigned long attr_gencount;
165 unsigned int cache_entry_index;
166 signed char duped;
167 bool plus;
168 bool eof;
169};
170
171static void nfs_readdir_array_init(struct nfs_cache_array *array)
172{
173 memset(array, 0, sizeof(struct nfs_cache_array));
174}
175
176static void nfs_readdir_page_init_array(struct page *page, u64 last_cookie)
177{
178 struct nfs_cache_array *array;
179
180 array = kmap_atomic(page);
181 nfs_readdir_array_init(array);
182 array->last_cookie = last_cookie;
183 array->cookies_are_ordered = 1;
184 kunmap_atomic(array);
185}
186
187
188
189
190static
191void nfs_readdir_clear_array(struct page *page)
192{
193 struct nfs_cache_array *array;
194 int i;
195
196 array = kmap_atomic(page);
197 for (i = 0; i < array->size; i++)
198 kfree(array->array[i].name);
199 nfs_readdir_array_init(array);
200 kunmap_atomic(array);
201}
202
203static struct page *
204nfs_readdir_page_array_alloc(u64 last_cookie, gfp_t gfp_flags)
205{
206 struct page *page = alloc_page(gfp_flags);
207 if (page)
208 nfs_readdir_page_init_array(page, last_cookie);
209 return page;
210}
211
212static void nfs_readdir_page_array_free(struct page *page)
213{
214 if (page) {
215 nfs_readdir_clear_array(page);
216 put_page(page);
217 }
218}
219
220static void nfs_readdir_array_set_eof(struct nfs_cache_array *array)
221{
222 array->page_is_eof = 1;
223 array->page_full = 1;
224}
225
226static bool nfs_readdir_array_is_full(struct nfs_cache_array *array)
227{
228 return array->page_full;
229}
230
231
232
233
234
235
236static const char *nfs_readdir_copy_name(const char *name, unsigned int len)
237{
238 const char *ret = kmemdup_nul(name, len, GFP_KERNEL);
239
240
241
242
243
244 if (ret != NULL)
245 kmemleak_not_leak(ret);
246 return ret;
247}
248
249
250
251
252static int nfs_readdir_array_can_expand(struct nfs_cache_array *array)
253{
254 struct nfs_cache_array_entry *cache_entry;
255
256 if (array->page_full)
257 return -ENOSPC;
258 cache_entry = &array->array[array->size + 1];
259 if ((char *)cache_entry - (char *)array > PAGE_SIZE) {
260 array->page_full = 1;
261 return -ENOSPC;
262 }
263 return 0;
264}
265
266static
267int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
268{
269 struct nfs_cache_array *array;
270 struct nfs_cache_array_entry *cache_entry;
271 const char *name;
272 int ret;
273
274 name = nfs_readdir_copy_name(entry->name, entry->len);
275 if (!name)
276 return -ENOMEM;
277
278 array = kmap_atomic(page);
279 ret = nfs_readdir_array_can_expand(array);
280 if (ret) {
281 kfree(name);
282 goto out;
283 }
284
285 cache_entry = &array->array[array->size];
286 cache_entry->cookie = entry->prev_cookie;
287 cache_entry->ino = entry->ino;
288 cache_entry->d_type = entry->d_type;
289 cache_entry->name_len = entry->len;
290 cache_entry->name = name;
291 array->last_cookie = entry->cookie;
292 if (array->last_cookie <= cache_entry->cookie)
293 array->cookies_are_ordered = 0;
294 array->size++;
295 if (entry->eof != 0)
296 nfs_readdir_array_set_eof(array);
297out:
298 kunmap_atomic(array);
299 return ret;
300}
301
302static struct page *nfs_readdir_page_get_locked(struct address_space *mapping,
303 pgoff_t index, u64 last_cookie)
304{
305 struct page *page;
306
307 page = grab_cache_page(mapping, index);
308 if (page && !PageUptodate(page)) {
309 nfs_readdir_page_init_array(page, last_cookie);
310 if (invalidate_inode_pages2_range(mapping, index + 1, -1) < 0)
311 nfs_zap_mapping(mapping->host, mapping);
312 SetPageUptodate(page);
313 }
314
315 return page;
316}
317
318static u64 nfs_readdir_page_last_cookie(struct page *page)
319{
320 struct nfs_cache_array *array;
321 u64 ret;
322
323 array = kmap_atomic(page);
324 ret = array->last_cookie;
325 kunmap_atomic(array);
326 return ret;
327}
328
329static bool nfs_readdir_page_needs_filling(struct page *page)
330{
331 struct nfs_cache_array *array;
332 bool ret;
333
334 array = kmap_atomic(page);
335 ret = !nfs_readdir_array_is_full(array);
336 kunmap_atomic(array);
337 return ret;
338}
339
340static void nfs_readdir_page_set_eof(struct page *page)
341{
342 struct nfs_cache_array *array;
343
344 array = kmap_atomic(page);
345 nfs_readdir_array_set_eof(array);
346 kunmap_atomic(array);
347}
348
349static void nfs_readdir_page_unlock_and_put(struct page *page)
350{
351 unlock_page(page);
352 put_page(page);
353}
354
355static struct page *nfs_readdir_page_get_next(struct address_space *mapping,
356 pgoff_t index, u64 cookie)
357{
358 struct page *page;
359
360 page = nfs_readdir_page_get_locked(mapping, index, cookie);
361 if (page) {
362 if (nfs_readdir_page_last_cookie(page) == cookie)
363 return page;
364 nfs_readdir_page_unlock_and_put(page);
365 }
366 return NULL;
367}
368
369static inline
370int is_32bit_api(void)
371{
372#ifdef CONFIG_COMPAT
373 return in_compat_syscall();
374#else
375 return (BITS_PER_LONG == 32);
376#endif
377}
378
379static
380bool nfs_readdir_use_cookie(const struct file *filp)
381{
382 if ((filp->f_mode & FMODE_32BITHASH) ||
383 (!(filp->f_mode & FMODE_64BITHASH) && is_32bit_api()))
384 return false;
385 return true;
386}
387
388static int nfs_readdir_search_for_pos(struct nfs_cache_array *array,
389 struct nfs_readdir_descriptor *desc)
390{
391 loff_t diff = desc->ctx->pos - desc->current_index;
392 unsigned int index;
393
394 if (diff < 0)
395 goto out_eof;
396 if (diff >= array->size) {
397 if (array->page_is_eof)
398 goto out_eof;
399 return -EAGAIN;
400 }
401
402 index = (unsigned int)diff;
403 desc->dir_cookie = array->array[index].cookie;
404 desc->cache_entry_index = index;
405 return 0;
406out_eof:
407 desc->eof = true;
408 return -EBADCOOKIE;
409}
410
411static bool
412nfs_readdir_inode_mapping_valid(struct nfs_inode *nfsi)
413{
414 if (nfsi->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA))
415 return false;
416 smp_rmb();
417 return !test_bit(NFS_INO_INVALIDATING, &nfsi->flags);
418}
419
420static bool nfs_readdir_array_cookie_in_range(struct nfs_cache_array *array,
421 u64 cookie)
422{
423 if (!array->cookies_are_ordered)
424 return true;
425
426 if (cookie >= array->last_cookie)
427 return false;
428 if (array->size && cookie < array->array[0].cookie)
429 return false;
430 return true;
431}
432
433static int nfs_readdir_search_for_cookie(struct nfs_cache_array *array,
434 struct nfs_readdir_descriptor *desc)
435{
436 int i;
437 loff_t new_pos;
438 int status = -EAGAIN;
439
440 if (!nfs_readdir_array_cookie_in_range(array, desc->dir_cookie))
441 goto check_eof;
442
443 for (i = 0; i < array->size; i++) {
444 if (array->array[i].cookie == desc->dir_cookie) {
445 struct nfs_inode *nfsi = NFS_I(file_inode(desc->file));
446
447 new_pos = desc->current_index + i;
448 if (desc->attr_gencount != nfsi->attr_gencount ||
449 !nfs_readdir_inode_mapping_valid(nfsi)) {
450 desc->duped = 0;
451 desc->attr_gencount = nfsi->attr_gencount;
452 } else if (new_pos < desc->prev_index) {
453 if (desc->duped > 0
454 && desc->dup_cookie == desc->dir_cookie) {
455 if (printk_ratelimit()) {
456 pr_notice("NFS: directory %pD2 contains a readdir loop."
457 "Please contact your server vendor. "
458 "The file: %s has duplicate cookie %llu\n",
459 desc->file, array->array[i].name, desc->dir_cookie);
460 }
461 status = -ELOOP;
462 goto out;
463 }
464 desc->dup_cookie = desc->dir_cookie;
465 desc->duped = -1;
466 }
467 if (nfs_readdir_use_cookie(desc->file))
468 desc->ctx->pos = desc->dir_cookie;
469 else
470 desc->ctx->pos = new_pos;
471 desc->prev_index = new_pos;
472 desc->cache_entry_index = i;
473 return 0;
474 }
475 }
476check_eof:
477 if (array->page_is_eof) {
478 status = -EBADCOOKIE;
479 if (desc->dir_cookie == array->last_cookie)
480 desc->eof = true;
481 }
482out:
483 return status;
484}
485
486static int nfs_readdir_search_array(struct nfs_readdir_descriptor *desc)
487{
488 struct nfs_cache_array *array;
489 int status;
490
491 array = kmap_atomic(desc->page);
492
493 if (desc->dir_cookie == 0)
494 status = nfs_readdir_search_for_pos(array, desc);
495 else
496 status = nfs_readdir_search_for_cookie(array, desc);
497
498 if (status == -EAGAIN) {
499 desc->last_cookie = array->last_cookie;
500 desc->current_index += array->size;
501 desc->page_index++;
502 }
503 kunmap_atomic(array);
504 return status;
505}
506
507
508static int nfs_readdir_xdr_filler(struct nfs_readdir_descriptor *desc,
509 __be32 *verf, u64 cookie,
510 struct page **pages, size_t bufsize,
511 __be32 *verf_res)
512{
513 struct inode *inode = file_inode(desc->file);
514 struct nfs_readdir_arg arg = {
515 .dentry = file_dentry(desc->file),
516 .cred = desc->file->f_cred,
517 .verf = verf,
518 .cookie = cookie,
519 .pages = pages,
520 .page_len = bufsize,
521 .plus = desc->plus,
522 };
523 struct nfs_readdir_res res = {
524 .verf = verf_res,
525 };
526 unsigned long timestamp, gencount;
527 int error;
528
529 again:
530 timestamp = jiffies;
531 gencount = nfs_inc_attr_generation_counter();
532 desc->dir_verifier = nfs_save_change_attribute(inode);
533 error = NFS_PROTO(inode)->readdir(&arg, &res);
534 if (error < 0) {
535
536 if (error == -ENOTSUPP && desc->plus) {
537 NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
538 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
539 desc->plus = arg.plus = false;
540 goto again;
541 }
542 goto error;
543 }
544 desc->timestamp = timestamp;
545 desc->gencount = gencount;
546error:
547 return error;
548}
549
550static int xdr_decode(struct nfs_readdir_descriptor *desc,
551 struct nfs_entry *entry, struct xdr_stream *xdr)
552{
553 struct inode *inode = file_inode(desc->file);
554 int error;
555
556 error = NFS_PROTO(inode)->decode_dirent(xdr, entry, desc->plus);
557 if (error)
558 return error;
559 entry->fattr->time_start = desc->timestamp;
560 entry->fattr->gencount = desc->gencount;
561 return 0;
562}
563
564
565
566
567static
568int nfs_same_file(struct dentry *dentry, struct nfs_entry *entry)
569{
570 struct inode *inode;
571 struct nfs_inode *nfsi;
572
573 if (d_really_is_negative(dentry))
574 return 0;
575
576 inode = d_inode(dentry);
577 if (is_bad_inode(inode) || NFS_STALE(inode))
578 return 0;
579
580 nfsi = NFS_I(inode);
581 if (entry->fattr->fileid != nfsi->fileid)
582 return 0;
583 if (entry->fh->size && nfs_compare_fh(entry->fh, &nfsi->fh) != 0)
584 return 0;
585 return 1;
586}
587
588static
589bool nfs_use_readdirplus(struct inode *dir, struct dir_context *ctx)
590{
591 if (!nfs_server_capable(dir, NFS_CAP_READDIRPLUS))
592 return false;
593 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(dir)->flags))
594 return true;
595 if (ctx->pos == 0)
596 return true;
597 return false;
598}
599
600
601
602
603
604
605void nfs_advise_use_readdirplus(struct inode *dir)
606{
607 struct nfs_inode *nfsi = NFS_I(dir);
608
609 if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS) &&
610 !list_empty(&nfsi->open_files))
611 set_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
612}
613
614
615
616
617
618
619
620
621
622void nfs_force_use_readdirplus(struct inode *dir)
623{
624 struct nfs_inode *nfsi = NFS_I(dir);
625
626 if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS) &&
627 !list_empty(&nfsi->open_files)) {
628 set_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
629 invalidate_mapping_pages(dir->i_mapping,
630 nfsi->page_index + 1, -1);
631 }
632}
633
634static
635void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
636 unsigned long dir_verifier)
637{
638 struct qstr filename = QSTR_INIT(entry->name, entry->len);
639 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
640 struct dentry *dentry;
641 struct dentry *alias;
642 struct inode *inode;
643 int status;
644
645 if (!(entry->fattr->valid & NFS_ATTR_FATTR_FILEID))
646 return;
647 if (!(entry->fattr->valid & NFS_ATTR_FATTR_FSID))
648 return;
649 if (filename.len == 0)
650 return;
651
652 if (strnlen(filename.name, filename.len) != filename.len)
653 return;
654
655 if (strnchr(filename.name, filename.len, '/'))
656 return;
657 if (filename.name[0] == '.') {
658 if (filename.len == 1)
659 return;
660 if (filename.len == 2 && filename.name[1] == '.')
661 return;
662 }
663 filename.hash = full_name_hash(parent, filename.name, filename.len);
664
665 dentry = d_lookup(parent, &filename);
666again:
667 if (!dentry) {
668 dentry = d_alloc_parallel(parent, &filename, &wq);
669 if (IS_ERR(dentry))
670 return;
671 }
672 if (!d_in_lookup(dentry)) {
673
674 if (!nfs_fsid_equal(&NFS_SB(dentry->d_sb)->fsid,
675 &entry->fattr->fsid))
676 goto out;
677 if (nfs_same_file(dentry, entry)) {
678 if (!entry->fh->size)
679 goto out;
680 nfs_set_verifier(dentry, dir_verifier);
681 status = nfs_refresh_inode(d_inode(dentry), entry->fattr);
682 if (!status)
683 nfs_setsecurity(d_inode(dentry), entry->fattr, entry->label);
684 goto out;
685 } else {
686 d_invalidate(dentry);
687 dput(dentry);
688 dentry = NULL;
689 goto again;
690 }
691 }
692 if (!entry->fh->size) {
693 d_lookup_done(dentry);
694 goto out;
695 }
696
697 inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr, entry->label);
698 alias = d_splice_alias(inode, dentry);
699 d_lookup_done(dentry);
700 if (alias) {
701 if (IS_ERR(alias))
702 goto out;
703 dput(dentry);
704 dentry = alias;
705 }
706 nfs_set_verifier(dentry, dir_verifier);
707out:
708 dput(dentry);
709}
710
711
712static int nfs_readdir_page_filler(struct nfs_readdir_descriptor *desc,
713 struct nfs_entry *entry,
714 struct page **xdr_pages,
715 unsigned int buflen,
716 struct page **arrays,
717 size_t narrays)
718{
719 struct address_space *mapping = desc->file->f_mapping;
720 struct xdr_stream stream;
721 struct xdr_buf buf;
722 struct page *scratch, *new, *page = *arrays;
723 int status;
724
725 scratch = alloc_page(GFP_KERNEL);
726 if (scratch == NULL)
727 return -ENOMEM;
728
729 xdr_init_decode_pages(&stream, &buf, xdr_pages, buflen);
730 xdr_set_scratch_page(&stream, scratch);
731
732 do {
733 if (entry->label)
734 entry->label->len = NFS4_MAXLABELLEN;
735
736 status = xdr_decode(desc, entry, &stream);
737 if (status != 0)
738 break;
739
740 if (desc->plus)
741 nfs_prime_dcache(file_dentry(desc->file), entry,
742 desc->dir_verifier);
743
744 status = nfs_readdir_add_to_array(entry, page);
745 if (status != -ENOSPC)
746 continue;
747
748 if (page->mapping != mapping) {
749 if (!--narrays)
750 break;
751 new = nfs_readdir_page_array_alloc(entry->prev_cookie,
752 GFP_KERNEL);
753 if (!new)
754 break;
755 arrays++;
756 *arrays = page = new;
757 } else {
758 new = nfs_readdir_page_get_next(mapping,
759 page->index + 1,
760 entry->prev_cookie);
761 if (!new)
762 break;
763 if (page != *arrays)
764 nfs_readdir_page_unlock_and_put(page);
765 page = new;
766 }
767 status = nfs_readdir_add_to_array(entry, page);
768 } while (!status && !entry->eof);
769
770 switch (status) {
771 case -EBADCOOKIE:
772 if (entry->eof) {
773 nfs_readdir_page_set_eof(page);
774 status = 0;
775 }
776 break;
777 case -ENOSPC:
778 case -EAGAIN:
779 status = 0;
780 break;
781 }
782
783 if (page != *arrays)
784 nfs_readdir_page_unlock_and_put(page);
785
786 put_page(scratch);
787 return status;
788}
789
790static void nfs_readdir_free_pages(struct page **pages, size_t npages)
791{
792 while (npages--)
793 put_page(pages[npages]);
794 kfree(pages);
795}
796
797
798
799
800
801static struct page **nfs_readdir_alloc_pages(size_t npages)
802{
803 struct page **pages;
804 size_t i;
805
806 pages = kmalloc_array(npages, sizeof(*pages), GFP_KERNEL);
807 if (!pages)
808 return NULL;
809 for (i = 0; i < npages; i++) {
810 struct page *page = alloc_page(GFP_KERNEL);
811 if (page == NULL)
812 goto out_freepages;
813 pages[i] = page;
814 }
815 return pages;
816
817out_freepages:
818 nfs_readdir_free_pages(pages, i);
819 return NULL;
820}
821
822static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor *desc,
823 __be32 *verf_arg, __be32 *verf_res,
824 struct page **arrays, size_t narrays)
825{
826 struct page **pages;
827 struct page *page = *arrays;
828 struct nfs_entry *entry;
829 size_t array_size;
830 struct inode *inode = file_inode(desc->file);
831 size_t dtsize = NFS_SERVER(inode)->dtsize;
832 int status = -ENOMEM;
833
834 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
835 if (!entry)
836 return -ENOMEM;
837 entry->cookie = nfs_readdir_page_last_cookie(page);
838 entry->fh = nfs_alloc_fhandle();
839 entry->fattr = nfs_alloc_fattr();
840 entry->server = NFS_SERVER(inode);
841 if (entry->fh == NULL || entry->fattr == NULL)
842 goto out;
843
844 entry->label = nfs4_label_alloc(NFS_SERVER(inode), GFP_NOWAIT);
845 if (IS_ERR(entry->label)) {
846 status = PTR_ERR(entry->label);
847 goto out;
848 }
849
850 array_size = (dtsize + PAGE_SIZE - 1) >> PAGE_SHIFT;
851 pages = nfs_readdir_alloc_pages(array_size);
852 if (!pages)
853 goto out_release_label;
854
855 do {
856 unsigned int pglen;
857 status = nfs_readdir_xdr_filler(desc, verf_arg, entry->cookie,
858 pages, dtsize,
859 verf_res);
860 if (status < 0)
861 break;
862
863 pglen = status;
864 if (pglen == 0) {
865 nfs_readdir_page_set_eof(page);
866 break;
867 }
868
869 verf_arg = verf_res;
870
871 status = nfs_readdir_page_filler(desc, entry, pages, pglen,
872 arrays, narrays);
873 } while (!status && nfs_readdir_page_needs_filling(page));
874
875 nfs_readdir_free_pages(pages, array_size);
876out_release_label:
877 nfs4_label_free(entry->label);
878out:
879 nfs_free_fattr(entry->fattr);
880 nfs_free_fhandle(entry->fh);
881 kfree(entry);
882 return status;
883}
884
885static void nfs_readdir_page_put(struct nfs_readdir_descriptor *desc)
886{
887 put_page(desc->page);
888 desc->page = NULL;
889}
890
891static void
892nfs_readdir_page_unlock_and_put_cached(struct nfs_readdir_descriptor *desc)
893{
894 unlock_page(desc->page);
895 nfs_readdir_page_put(desc);
896}
897
898static struct page *
899nfs_readdir_page_get_cached(struct nfs_readdir_descriptor *desc)
900{
901 return nfs_readdir_page_get_locked(desc->file->f_mapping,
902 desc->page_index,
903 desc->last_cookie);
904}
905
906
907
908
909
910static int find_and_lock_cache_page(struct nfs_readdir_descriptor *desc)
911{
912 struct inode *inode = file_inode(desc->file);
913 struct nfs_inode *nfsi = NFS_I(inode);
914 __be32 verf[NFS_DIR_VERIFIER_SIZE];
915 int res;
916
917 desc->page = nfs_readdir_page_get_cached(desc);
918 if (!desc->page)
919 return -ENOMEM;
920 if (nfs_readdir_page_needs_filling(desc->page)) {
921 res = nfs_readdir_xdr_to_array(desc, nfsi->cookieverf, verf,
922 &desc->page, 1);
923 if (res < 0) {
924 nfs_readdir_page_unlock_and_put_cached(desc);
925 if (res == -EBADCOOKIE || res == -ENOTSYNC) {
926 invalidate_inode_pages2(desc->file->f_mapping);
927 desc->page_index = 0;
928 return -EAGAIN;
929 }
930 return res;
931 }
932
933
934
935 if (desc->page_index == 0)
936 memcpy(nfsi->cookieverf, verf,
937 sizeof(nfsi->cookieverf));
938 }
939 res = nfs_readdir_search_array(desc);
940 if (res == 0) {
941 nfsi->page_index = desc->page_index;
942 return 0;
943 }
944 nfs_readdir_page_unlock_and_put_cached(desc);
945 return res;
946}
947
948static bool nfs_readdir_dont_search_cache(struct nfs_readdir_descriptor *desc)
949{
950 struct address_space *mapping = desc->file->f_mapping;
951 struct inode *dir = file_inode(desc->file);
952 unsigned int dtsize = NFS_SERVER(dir)->dtsize;
953 loff_t size = i_size_read(dir);
954
955
956
957
958
959 return desc->dir_cookie != 0 && mapping->nrpages == 0 && size > dtsize;
960}
961
962
963static int readdir_search_pagecache(struct nfs_readdir_descriptor *desc)
964{
965 int res;
966
967 if (nfs_readdir_dont_search_cache(desc))
968 return -EBADCOOKIE;
969
970 do {
971 if (desc->page_index == 0) {
972 desc->current_index = 0;
973 desc->prev_index = 0;
974 desc->last_cookie = 0;
975 }
976 res = find_and_lock_cache_page(desc);
977 } while (res == -EAGAIN);
978 return res;
979}
980
981
982
983
984static void nfs_do_filldir(struct nfs_readdir_descriptor *desc,
985 const __be32 *verf)
986{
987 struct file *file = desc->file;
988 struct nfs_cache_array *array;
989 unsigned int i = 0;
990
991 array = kmap(desc->page);
992 for (i = desc->cache_entry_index; i < array->size; i++) {
993 struct nfs_cache_array_entry *ent;
994
995 ent = &array->array[i];
996 if (!dir_emit(desc->ctx, ent->name, ent->name_len,
997 nfs_compat_user_ino64(ent->ino), ent->d_type)) {
998 desc->eof = true;
999 break;
1000 }
1001 memcpy(desc->verf, verf, sizeof(desc->verf));
1002 if (i < (array->size-1))
1003 desc->dir_cookie = array->array[i+1].cookie;
1004 else
1005 desc->dir_cookie = array->last_cookie;
1006 if (nfs_readdir_use_cookie(file))
1007 desc->ctx->pos = desc->dir_cookie;
1008 else
1009 desc->ctx->pos++;
1010 if (desc->duped != 0)
1011 desc->duped = 1;
1012 }
1013 if (array->page_is_eof)
1014 desc->eof = true;
1015
1016 kunmap(desc->page);
1017 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %llu\n",
1018 (unsigned long long)desc->dir_cookie);
1019}
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033static int uncached_readdir(struct nfs_readdir_descriptor *desc)
1034{
1035 struct page **arrays;
1036 size_t i, sz = 512;
1037 __be32 verf[NFS_DIR_VERIFIER_SIZE];
1038 int status = -ENOMEM;
1039
1040 dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %llu\n",
1041 (unsigned long long)desc->dir_cookie);
1042
1043 arrays = kcalloc(sz, sizeof(*arrays), GFP_KERNEL);
1044 if (!arrays)
1045 goto out;
1046 arrays[0] = nfs_readdir_page_array_alloc(desc->dir_cookie, GFP_KERNEL);
1047 if (!arrays[0])
1048 goto out;
1049
1050 desc->page_index = 0;
1051 desc->last_cookie = desc->dir_cookie;
1052 desc->duped = 0;
1053
1054 status = nfs_readdir_xdr_to_array(desc, desc->verf, verf, arrays, sz);
1055
1056 for (i = 0; !desc->eof && i < sz && arrays[i]; i++) {
1057 desc->page = arrays[i];
1058 nfs_do_filldir(desc, verf);
1059 }
1060 desc->page = NULL;
1061
1062
1063 for (i = 0; i < sz && arrays[i]; i++)
1064 nfs_readdir_page_array_free(arrays[i]);
1065out:
1066 kfree(arrays);
1067 dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status);
1068 return status;
1069}
1070
1071
1072
1073
1074
1075static int nfs_readdir(struct file *file, struct dir_context *ctx)
1076{
1077 struct dentry *dentry = file_dentry(file);
1078 struct inode *inode = d_inode(dentry);
1079 struct nfs_inode *nfsi = NFS_I(inode);
1080 struct nfs_open_dir_context *dir_ctx = file->private_data;
1081 struct nfs_readdir_descriptor *desc;
1082 int res;
1083
1084 dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
1085 file, (long long)ctx->pos);
1086 nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
1087
1088
1089
1090
1091
1092
1093
1094 if (ctx->pos == 0 || nfs_attribute_cache_expired(inode)) {
1095 res = nfs_revalidate_mapping(inode, file->f_mapping);
1096 if (res < 0)
1097 goto out;
1098 }
1099
1100 res = -ENOMEM;
1101 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
1102 if (!desc)
1103 goto out;
1104 desc->file = file;
1105 desc->ctx = ctx;
1106 desc->plus = nfs_use_readdirplus(inode, ctx);
1107
1108 spin_lock(&file->f_lock);
1109 desc->dir_cookie = dir_ctx->dir_cookie;
1110 desc->dup_cookie = dir_ctx->dup_cookie;
1111 desc->duped = dir_ctx->duped;
1112 desc->attr_gencount = dir_ctx->attr_gencount;
1113 memcpy(desc->verf, dir_ctx->verf, sizeof(desc->verf));
1114 spin_unlock(&file->f_lock);
1115
1116 do {
1117 res = readdir_search_pagecache(desc);
1118
1119 if (res == -EBADCOOKIE) {
1120 res = 0;
1121
1122 if (desc->dir_cookie && !desc->eof) {
1123
1124 res = uncached_readdir(desc);
1125 if (res == 0)
1126 continue;
1127 if (res == -EBADCOOKIE || res == -ENOTSYNC)
1128 res = 0;
1129 }
1130 break;
1131 }
1132 if (res == -ETOOSMALL && desc->plus) {
1133 clear_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
1134 nfs_zap_caches(inode);
1135 desc->page_index = 0;
1136 desc->plus = false;
1137 desc->eof = false;
1138 continue;
1139 }
1140 if (res < 0)
1141 break;
1142
1143 nfs_do_filldir(desc, nfsi->cookieverf);
1144 nfs_readdir_page_unlock_and_put_cached(desc);
1145 } while (!desc->eof);
1146
1147 spin_lock(&file->f_lock);
1148 dir_ctx->dir_cookie = desc->dir_cookie;
1149 dir_ctx->dup_cookie = desc->dup_cookie;
1150 dir_ctx->duped = desc->duped;
1151 dir_ctx->attr_gencount = desc->attr_gencount;
1152 memcpy(dir_ctx->verf, desc->verf, sizeof(dir_ctx->verf));
1153 spin_unlock(&file->f_lock);
1154
1155 kfree(desc);
1156
1157out:
1158 dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file, res);
1159 return res;
1160}
1161
1162static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int whence)
1163{
1164 struct nfs_open_dir_context *dir_ctx = filp->private_data;
1165
1166 dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
1167 filp, offset, whence);
1168
1169 switch (whence) {
1170 default:
1171 return -EINVAL;
1172 case SEEK_SET:
1173 if (offset < 0)
1174 return -EINVAL;
1175 spin_lock(&filp->f_lock);
1176 break;
1177 case SEEK_CUR:
1178 if (offset == 0)
1179 return filp->f_pos;
1180 spin_lock(&filp->f_lock);
1181 offset += filp->f_pos;
1182 if (offset < 0) {
1183 spin_unlock(&filp->f_lock);
1184 return -EINVAL;
1185 }
1186 }
1187 if (offset != filp->f_pos) {
1188 filp->f_pos = offset;
1189 if (nfs_readdir_use_cookie(filp))
1190 dir_ctx->dir_cookie = offset;
1191 else
1192 dir_ctx->dir_cookie = 0;
1193 if (offset == 0)
1194 memset(dir_ctx->verf, 0, sizeof(dir_ctx->verf));
1195 dir_ctx->duped = 0;
1196 }
1197 spin_unlock(&filp->f_lock);
1198 return offset;
1199}
1200
1201
1202
1203
1204
1205static int nfs_fsync_dir(struct file *filp, loff_t start, loff_t end,
1206 int datasync)
1207{
1208 dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp, datasync);
1209
1210 nfs_inc_stats(file_inode(filp), NFSIOS_VFSFSYNC);
1211 return 0;
1212}
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227void nfs_force_lookup_revalidate(struct inode *dir)
1228{
1229 NFS_I(dir)->cache_change_attribute += 2;
1230}
1231EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate);
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242static bool nfs_verify_change_attribute(struct inode *dir, unsigned long verf)
1243{
1244 return (verf & ~1UL) == nfs_save_change_attribute(dir);
1245}
1246
1247static void nfs_set_verifier_delegated(unsigned long *verf)
1248{
1249 *verf |= 1UL;
1250}
1251
1252#if IS_ENABLED(CONFIG_NFS_V4)
1253static void nfs_unset_verifier_delegated(unsigned long *verf)
1254{
1255 *verf &= ~1UL;
1256}
1257#endif
1258
1259static bool nfs_test_verifier_delegated(unsigned long verf)
1260{
1261 return verf & 1;
1262}
1263
1264static bool nfs_verifier_is_delegated(struct dentry *dentry)
1265{
1266 return nfs_test_verifier_delegated(dentry->d_time);
1267}
1268
1269static void nfs_set_verifier_locked(struct dentry *dentry, unsigned long verf)
1270{
1271 struct inode *inode = d_inode(dentry);
1272
1273 if (!nfs_verifier_is_delegated(dentry) &&
1274 !nfs_verify_change_attribute(d_inode(dentry->d_parent), verf))
1275 goto out;
1276 if (inode && NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
1277 nfs_set_verifier_delegated(&verf);
1278out:
1279 dentry->d_time = verf;
1280}
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292void nfs_set_verifier(struct dentry *dentry, unsigned long verf)
1293{
1294
1295 spin_lock(&dentry->d_lock);
1296 nfs_set_verifier_locked(dentry, verf);
1297 spin_unlock(&dentry->d_lock);
1298}
1299EXPORT_SYMBOL_GPL(nfs_set_verifier);
1300
1301#if IS_ENABLED(CONFIG_NFS_V4)
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312void nfs_clear_verifier_delegated(struct inode *inode)
1313{
1314 struct dentry *alias;
1315
1316 if (!inode)
1317 return;
1318 spin_lock(&inode->i_lock);
1319 hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {
1320 spin_lock(&alias->d_lock);
1321 nfs_unset_verifier_delegated(&alias->d_time);
1322 spin_unlock(&alias->d_lock);
1323 }
1324 spin_unlock(&inode->i_lock);
1325}
1326EXPORT_SYMBOL_GPL(nfs_clear_verifier_delegated);
1327#endif
1328
1329
1330
1331
1332
1333
1334
1335static int nfs_check_verifier(struct inode *dir, struct dentry *dentry,
1336 int rcu_walk)
1337{
1338 if (IS_ROOT(dentry))
1339 return 1;
1340 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
1341 return 0;
1342 if (!nfs_verify_change_attribute(dir, dentry->d_time))
1343 return 0;
1344
1345 if (nfs_mapping_need_revalidate_inode(dir)) {
1346 if (rcu_walk)
1347 return 0;
1348 if (__nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0)
1349 return 0;
1350 }
1351 if (!nfs_verify_change_attribute(dir, dentry->d_time))
1352 return 0;
1353 return 1;
1354}
1355
1356
1357
1358
1359
1360static int nfs_is_exclusive_create(struct inode *dir, unsigned int flags)
1361{
1362 if (NFS_PROTO(dir)->version == 2)
1363 return 0;
1364 return flags & LOOKUP_EXCL;
1365}
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375static
1376int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags)
1377{
1378 struct nfs_server *server = NFS_SERVER(inode);
1379 int ret;
1380
1381 if (IS_AUTOMOUNT(inode))
1382 return 0;
1383
1384 if (flags & LOOKUP_OPEN) {
1385 switch (inode->i_mode & S_IFMT) {
1386 case S_IFREG:
1387
1388 if (server->caps & NFS_CAP_ATOMIC_OPEN)
1389 goto out;
1390 fallthrough;
1391 case S_IFDIR:
1392 if (server->flags & NFS_MOUNT_NOCTO)
1393 break;
1394
1395 goto out_force;
1396 }
1397 }
1398
1399
1400 if (flags & LOOKUP_REVAL)
1401 goto out_force;
1402out:
1403 return (inode->i_nlink == 0) ? -ESTALE : 0;
1404out_force:
1405 if (flags & LOOKUP_RCU)
1406 return -ECHILD;
1407 ret = __nfs_revalidate_inode(server, inode);
1408 if (ret != 0)
1409 return ret;
1410 goto out;
1411}
1412
1413static void nfs_mark_dir_for_revalidate(struct inode *inode)
1414{
1415 spin_lock(&inode->i_lock);
1416 nfs_set_cache_invalid(inode, NFS_INO_REVAL_PAGECACHE);
1417 spin_unlock(&inode->i_lock);
1418}
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433static inline
1434int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
1435 unsigned int flags)
1436{
1437 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
1438 return 0;
1439 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG)
1440 return 1;
1441 return !nfs_check_verifier(dir, dentry, flags & LOOKUP_RCU);
1442}
1443
1444static int
1445nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry,
1446 struct inode *inode, int error)
1447{
1448 switch (error) {
1449 case 1:
1450 dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is valid\n",
1451 __func__, dentry);
1452 return 1;
1453 case 0:
1454
1455
1456
1457
1458
1459
1460 if (inode && IS_ROOT(dentry))
1461 return 1;
1462 dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) is invalid\n",
1463 __func__, dentry);
1464 return 0;
1465 }
1466 dfprintk(LOOKUPCACHE, "NFS: %s(%pd2) lookup returned error %d\n",
1467 __func__, dentry, error);
1468 return error;
1469}
1470
1471static int
1472nfs_lookup_revalidate_negative(struct inode *dir, struct dentry *dentry,
1473 unsigned int flags)
1474{
1475 int ret = 1;
1476 if (nfs_neg_need_reval(dir, dentry, flags)) {
1477 if (flags & LOOKUP_RCU)
1478 return -ECHILD;
1479 ret = 0;
1480 }
1481 return nfs_lookup_revalidate_done(dir, dentry, NULL, ret);
1482}
1483
1484static int
1485nfs_lookup_revalidate_delegated(struct inode *dir, struct dentry *dentry,
1486 struct inode *inode)
1487{
1488 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1489 return nfs_lookup_revalidate_done(dir, dentry, inode, 1);
1490}
1491
1492static int
1493nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry,
1494 struct inode *inode)
1495{
1496 struct nfs_fh *fhandle;
1497 struct nfs_fattr *fattr;
1498 struct nfs4_label *label;
1499 unsigned long dir_verifier;
1500 int ret;
1501
1502 ret = -ENOMEM;
1503 fhandle = nfs_alloc_fhandle();
1504 fattr = nfs_alloc_fattr();
1505 label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
1506 if (fhandle == NULL || fattr == NULL || IS_ERR(label))
1507 goto out;
1508
1509 dir_verifier = nfs_save_change_attribute(dir);
1510 ret = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, label);
1511 if (ret < 0) {
1512 switch (ret) {
1513 case -ESTALE:
1514 case -ENOENT:
1515 ret = 0;
1516 break;
1517 case -ETIMEDOUT:
1518 if (NFS_SERVER(inode)->flags & NFS_MOUNT_SOFTREVAL)
1519 ret = 1;
1520 }
1521 goto out;
1522 }
1523 ret = 0;
1524 if (nfs_compare_fh(NFS_FH(inode), fhandle))
1525 goto out;
1526 if (nfs_refresh_inode(inode, fattr) < 0)
1527 goto out;
1528
1529 nfs_setsecurity(inode, fattr, label);
1530 nfs_set_verifier(dentry, dir_verifier);
1531
1532
1533 nfs_force_use_readdirplus(dir);
1534 ret = 1;
1535out:
1536 nfs_free_fattr(fattr);
1537 nfs_free_fhandle(fhandle);
1538 nfs4_label_free(label);
1539
1540
1541
1542
1543
1544 if (!ret && nfs_verify_change_attribute(dir, dentry->d_time))
1545 nfs_mark_dir_for_revalidate(dir);
1546 return nfs_lookup_revalidate_done(dir, dentry, inode, ret);
1547}
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560static int
1561nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
1562 unsigned int flags)
1563{
1564 struct inode *inode;
1565 int error;
1566
1567 nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
1568 inode = d_inode(dentry);
1569
1570 if (!inode)
1571 return nfs_lookup_revalidate_negative(dir, dentry, flags);
1572
1573 if (is_bad_inode(inode)) {
1574 dfprintk(LOOKUPCACHE, "%s: %pd2 has dud inode\n",
1575 __func__, dentry);
1576 goto out_bad;
1577 }
1578
1579 if (nfs_verifier_is_delegated(dentry))
1580 return nfs_lookup_revalidate_delegated(dir, dentry, inode);
1581
1582
1583 if (!(flags & (LOOKUP_EXCL | LOOKUP_REVAL)) &&
1584 nfs_check_verifier(dir, dentry, flags & LOOKUP_RCU)) {
1585 error = nfs_lookup_verify_inode(inode, flags);
1586 if (error) {
1587 if (error == -ESTALE)
1588 nfs_mark_dir_for_revalidate(dir);
1589 goto out_bad;
1590 }
1591 nfs_advise_use_readdirplus(dir);
1592 goto out_valid;
1593 }
1594
1595 if (flags & LOOKUP_RCU)
1596 return -ECHILD;
1597
1598 if (NFS_STALE(inode))
1599 goto out_bad;
1600
1601 trace_nfs_lookup_revalidate_enter(dir, dentry, flags);
1602 error = nfs_lookup_revalidate_dentry(dir, dentry, inode);
1603 trace_nfs_lookup_revalidate_exit(dir, dentry, flags, error);
1604 return error;
1605out_valid:
1606 return nfs_lookup_revalidate_done(dir, dentry, inode, 1);
1607out_bad:
1608 if (flags & LOOKUP_RCU)
1609 return -ECHILD;
1610 return nfs_lookup_revalidate_done(dir, dentry, inode, 0);
1611}
1612
1613static int
1614__nfs_lookup_revalidate(struct dentry *dentry, unsigned int flags,
1615 int (*reval)(struct inode *, struct dentry *, unsigned int))
1616{
1617 struct dentry *parent;
1618 struct inode *dir;
1619 int ret;
1620
1621 if (flags & LOOKUP_RCU) {
1622 parent = READ_ONCE(dentry->d_parent);
1623 dir = d_inode_rcu(parent);
1624 if (!dir)
1625 return -ECHILD;
1626 ret = reval(dir, dentry, flags);
1627 if (parent != READ_ONCE(dentry->d_parent))
1628 return -ECHILD;
1629 } else {
1630 parent = dget_parent(dentry);
1631 ret = reval(d_inode(parent), dentry, flags);
1632 dput(parent);
1633 }
1634 return ret;
1635}
1636
1637static int nfs_lookup_revalidate(struct dentry *dentry, unsigned int flags)
1638{
1639 return __nfs_lookup_revalidate(dentry, flags, nfs_do_lookup_revalidate);
1640}
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651static int nfs_weak_revalidate(struct dentry *dentry, unsigned int flags)
1652{
1653 struct inode *inode = d_inode(dentry);
1654 int error = 0;
1655
1656
1657
1658
1659
1660
1661 if (!inode) {
1662 dfprintk(LOOKUPCACHE, "%s: %pd2 has negative inode\n",
1663 __func__, dentry);
1664 return 1;
1665 }
1666
1667 if (is_bad_inode(inode)) {
1668 dfprintk(LOOKUPCACHE, "%s: %pd2 has dud inode\n",
1669 __func__, dentry);
1670 return 0;
1671 }
1672
1673 error = nfs_lookup_verify_inode(inode, flags);
1674 dfprintk(LOOKUPCACHE, "NFS: %s: inode %lu is %s\n",
1675 __func__, inode->i_ino, error ? "invalid" : "valid");
1676 return !error;
1677}
1678
1679
1680
1681
1682static int nfs_dentry_delete(const struct dentry *dentry)
1683{
1684 dfprintk(VFS, "NFS: dentry_delete(%pd2, %x)\n",
1685 dentry, dentry->d_flags);
1686
1687
1688 if (d_really_is_positive(dentry) && NFS_STALE(d_inode(dentry)))
1689 return 1;
1690
1691 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1692
1693 return 1;
1694 }
1695 if (!(dentry->d_sb->s_flags & SB_ACTIVE)) {
1696
1697
1698 return 1;
1699 }
1700 return 0;
1701
1702}
1703
1704
1705static void nfs_drop_nlink(struct inode *inode)
1706{
1707 spin_lock(&inode->i_lock);
1708
1709 if (inode->i_nlink > 0)
1710 drop_nlink(inode);
1711 NFS_I(inode)->attr_gencount = nfs_inc_attr_generation_counter();
1712 nfs_set_cache_invalid(
1713 inode, NFS_INO_INVALID_CHANGE | NFS_INO_INVALID_CTIME |
1714 NFS_INO_INVALID_NLINK);
1715 spin_unlock(&inode->i_lock);
1716}
1717
1718
1719
1720
1721
1722static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
1723{
1724 if (S_ISDIR(inode->i_mode))
1725
1726 nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1727
1728 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1729 nfs_complete_unlink(dentry, inode);
1730 nfs_drop_nlink(inode);
1731 }
1732 iput(inode);
1733}
1734
1735static void nfs_d_release(struct dentry *dentry)
1736{
1737
1738 if (unlikely(dentry->d_fsdata)) {
1739 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1740 WARN_ON(1);
1741 else
1742 kfree(dentry->d_fsdata);
1743 }
1744}
1745
1746const struct dentry_operations nfs_dentry_operations = {
1747 .d_revalidate = nfs_lookup_revalidate,
1748 .d_weak_revalidate = nfs_weak_revalidate,
1749 .d_delete = nfs_dentry_delete,
1750 .d_iput = nfs_dentry_iput,
1751 .d_automount = nfs_d_automount,
1752 .d_release = nfs_d_release,
1753};
1754EXPORT_SYMBOL_GPL(nfs_dentry_operations);
1755
1756struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
1757{
1758 struct dentry *res;
1759 struct inode *inode = NULL;
1760 struct nfs_fh *fhandle = NULL;
1761 struct nfs_fattr *fattr = NULL;
1762 struct nfs4_label *label = NULL;
1763 unsigned long dir_verifier;
1764 int error;
1765
1766 dfprintk(VFS, "NFS: lookup(%pd2)\n", dentry);
1767 nfs_inc_stats(dir, NFSIOS_VFSLOOKUP);
1768
1769 if (unlikely(dentry->d_name.len > NFS_SERVER(dir)->namelen))
1770 return ERR_PTR(-ENAMETOOLONG);
1771
1772
1773
1774
1775
1776 if (nfs_is_exclusive_create(dir, flags) || flags & LOOKUP_RENAME_TARGET)
1777 return NULL;
1778
1779 res = ERR_PTR(-ENOMEM);
1780 fhandle = nfs_alloc_fhandle();
1781 fattr = nfs_alloc_fattr();
1782 if (fhandle == NULL || fattr == NULL)
1783 goto out;
1784
1785 label = nfs4_label_alloc(NFS_SERVER(dir), GFP_NOWAIT);
1786 if (IS_ERR(label))
1787 goto out;
1788
1789 dir_verifier = nfs_save_change_attribute(dir);
1790 trace_nfs_lookup_enter(dir, dentry, flags);
1791 error = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, label);
1792 if (error == -ENOENT)
1793 goto no_entry;
1794 if (error < 0) {
1795 res = ERR_PTR(error);
1796 goto out_label;
1797 }
1798 inode = nfs_fhget(dentry->d_sb, fhandle, fattr, label);
1799 res = ERR_CAST(inode);
1800 if (IS_ERR(res))
1801 goto out_label;
1802
1803
1804 nfs_force_use_readdirplus(dir);
1805
1806no_entry:
1807 res = d_splice_alias(inode, dentry);
1808 if (res != NULL) {
1809 if (IS_ERR(res))
1810 goto out_label;
1811 dentry = res;
1812 }
1813 nfs_set_verifier(dentry, dir_verifier);
1814out_label:
1815 trace_nfs_lookup_exit(dir, dentry, flags, error);
1816 nfs4_label_free(label);
1817out:
1818 nfs_free_fattr(fattr);
1819 nfs_free_fhandle(fhandle);
1820 return res;
1821}
1822EXPORT_SYMBOL_GPL(nfs_lookup);
1823
1824#if IS_ENABLED(CONFIG_NFS_V4)
1825static int nfs4_lookup_revalidate(struct dentry *, unsigned int);
1826
1827const struct dentry_operations nfs4_dentry_operations = {
1828 .d_revalidate = nfs4_lookup_revalidate,
1829 .d_weak_revalidate = nfs_weak_revalidate,
1830 .d_delete = nfs_dentry_delete,
1831 .d_iput = nfs_dentry_iput,
1832 .d_automount = nfs_d_automount,
1833 .d_release = nfs_d_release,
1834};
1835EXPORT_SYMBOL_GPL(nfs4_dentry_operations);
1836
1837static fmode_t flags_to_mode(int flags)
1838{
1839 fmode_t res = (__force fmode_t)flags & FMODE_EXEC;
1840 if ((flags & O_ACCMODE) != O_WRONLY)
1841 res |= FMODE_READ;
1842 if ((flags & O_ACCMODE) != O_RDONLY)
1843 res |= FMODE_WRITE;
1844 return res;
1845}
1846
1847static struct nfs_open_context *create_nfs_open_context(struct dentry *dentry, int open_flags, struct file *filp)
1848{
1849 return alloc_nfs_open_context(dentry, flags_to_mode(open_flags), filp);
1850}
1851
1852static int do_open(struct inode *inode, struct file *filp)
1853{
1854 nfs_fscache_open_file(inode, filp);
1855 return 0;
1856}
1857
1858static int nfs_finish_open(struct nfs_open_context *ctx,
1859 struct dentry *dentry,
1860 struct file *file, unsigned open_flags)
1861{
1862 int err;
1863
1864 err = finish_open(file, dentry, do_open);
1865 if (err)
1866 goto out;
1867 if (S_ISREG(file->f_path.dentry->d_inode->i_mode))
1868 nfs_file_set_open_context(file, ctx);
1869 else
1870 err = -EOPENSTALE;
1871out:
1872 return err;
1873}
1874
1875int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
1876 struct file *file, unsigned open_flags,
1877 umode_t mode)
1878{
1879 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
1880 struct nfs_open_context *ctx;
1881 struct dentry *res;
1882 struct iattr attr = { .ia_valid = ATTR_OPEN };
1883 struct inode *inode;
1884 unsigned int lookup_flags = 0;
1885 bool switched = false;
1886 int created = 0;
1887 int err;
1888
1889
1890 BUG_ON(d_inode(dentry));
1891
1892 dfprintk(VFS, "NFS: atomic_open(%s/%lu), %pd\n",
1893 dir->i_sb->s_id, dir->i_ino, dentry);
1894
1895 err = nfs_check_flags(open_flags);
1896 if (err)
1897 return err;
1898
1899
1900 if ((open_flags & O_DIRECTORY)) {
1901 if (!d_in_lookup(dentry)) {
1902
1903
1904
1905
1906
1907 return -ENOENT;
1908 }
1909 lookup_flags = LOOKUP_OPEN|LOOKUP_DIRECTORY;
1910 goto no_open;
1911 }
1912
1913 if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
1914 return -ENAMETOOLONG;
1915
1916 if (open_flags & O_CREAT) {
1917 struct nfs_server *server = NFS_SERVER(dir);
1918
1919 if (!(server->attr_bitmask[2] & FATTR4_WORD2_MODE_UMASK))
1920 mode &= ~current_umask();
1921
1922 attr.ia_valid |= ATTR_MODE;
1923 attr.ia_mode = mode;
1924 }
1925 if (open_flags & O_TRUNC) {
1926 attr.ia_valid |= ATTR_SIZE;
1927 attr.ia_size = 0;
1928 }
1929
1930 if (!(open_flags & O_CREAT) && !d_in_lookup(dentry)) {
1931 d_drop(dentry);
1932 switched = true;
1933 dentry = d_alloc_parallel(dentry->d_parent,
1934 &dentry->d_name, &wq);
1935 if (IS_ERR(dentry))
1936 return PTR_ERR(dentry);
1937 if (unlikely(!d_in_lookup(dentry)))
1938 return finish_no_open(file, dentry);
1939 }
1940
1941 ctx = create_nfs_open_context(dentry, open_flags, file);
1942 err = PTR_ERR(ctx);
1943 if (IS_ERR(ctx))
1944 goto out;
1945
1946 trace_nfs_atomic_open_enter(dir, ctx, open_flags);
1947 inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr, &created);
1948 if (created)
1949 file->f_mode |= FMODE_CREATED;
1950 if (IS_ERR(inode)) {
1951 err = PTR_ERR(inode);
1952 trace_nfs_atomic_open_exit(dir, ctx, open_flags, err);
1953 put_nfs_open_context(ctx);
1954 d_drop(dentry);
1955 switch (err) {
1956 case -ENOENT:
1957 d_splice_alias(NULL, dentry);
1958 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1959 break;
1960 case -EISDIR:
1961 case -ENOTDIR:
1962 goto no_open;
1963 case -ELOOP:
1964 if (!(open_flags & O_NOFOLLOW))
1965 goto no_open;
1966 break;
1967
1968 default:
1969 break;
1970 }
1971 goto out;
1972 }
1973
1974 err = nfs_finish_open(ctx, ctx->dentry, file, open_flags);
1975 trace_nfs_atomic_open_exit(dir, ctx, open_flags, err);
1976 put_nfs_open_context(ctx);
1977out:
1978 if (unlikely(switched)) {
1979 d_lookup_done(dentry);
1980 dput(dentry);
1981 }
1982 return err;
1983
1984no_open:
1985 res = nfs_lookup(dir, dentry, lookup_flags);
1986 if (switched) {
1987 d_lookup_done(dentry);
1988 if (!res)
1989 res = dentry;
1990 else
1991 dput(dentry);
1992 }
1993 if (IS_ERR(res))
1994 return PTR_ERR(res);
1995 return finish_no_open(file, res);
1996}
1997EXPORT_SYMBOL_GPL(nfs_atomic_open);
1998
1999static int
2000nfs4_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
2001 unsigned int flags)
2002{
2003 struct inode *inode;
2004
2005 if (!(flags & LOOKUP_OPEN) || (flags & LOOKUP_DIRECTORY))
2006 goto full_reval;
2007 if (d_mountpoint(dentry))
2008 goto full_reval;
2009
2010 inode = d_inode(dentry);
2011
2012
2013
2014
2015 if (inode == NULL)
2016 goto full_reval;
2017
2018 if (nfs_verifier_is_delegated(dentry))
2019 return nfs_lookup_revalidate_delegated(dir, dentry, inode);
2020
2021
2022 if (!S_ISREG(inode->i_mode))
2023 goto full_reval;
2024
2025
2026 if (flags & (LOOKUP_EXCL | LOOKUP_REVAL))
2027 goto reval_dentry;
2028
2029
2030 if (!nfs_check_verifier(dir, dentry, flags & LOOKUP_RCU))
2031 goto reval_dentry;
2032
2033
2034 return 1;
2035reval_dentry:
2036 if (flags & LOOKUP_RCU)
2037 return -ECHILD;
2038 return nfs_lookup_revalidate_dentry(dir, dentry, inode);
2039
2040full_reval:
2041 return nfs_do_lookup_revalidate(dir, dentry, flags);
2042}
2043
2044static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags)
2045{
2046 return __nfs_lookup_revalidate(dentry, flags,
2047 nfs4_do_lookup_revalidate);
2048}
2049
2050#endif
2051
2052struct dentry *
2053nfs_add_or_obtain(struct dentry *dentry, struct nfs_fh *fhandle,
2054 struct nfs_fattr *fattr,
2055 struct nfs4_label *label)
2056{
2057 struct dentry *parent = dget_parent(dentry);
2058 struct inode *dir = d_inode(parent);
2059 struct inode *inode;
2060 struct dentry *d;
2061 int error;
2062
2063 d_drop(dentry);
2064
2065 if (fhandle->size == 0) {
2066 error = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, NULL);
2067 if (error)
2068 goto out_error;
2069 }
2070 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
2071 if (!(fattr->valid & NFS_ATTR_FATTR)) {
2072 struct nfs_server *server = NFS_SB(dentry->d_sb);
2073 error = server->nfs_client->rpc_ops->getattr(server, fhandle,
2074 fattr, NULL, NULL);
2075 if (error < 0)
2076 goto out_error;
2077 }
2078 inode = nfs_fhget(dentry->d_sb, fhandle, fattr, label);
2079 d = d_splice_alias(inode, dentry);
2080out:
2081 dput(parent);
2082 return d;
2083out_error:
2084 d = ERR_PTR(error);
2085 goto out;
2086}
2087EXPORT_SYMBOL_GPL(nfs_add_or_obtain);
2088
2089
2090
2091
2092int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
2093 struct nfs_fattr *fattr,
2094 struct nfs4_label *label)
2095{
2096 struct dentry *d;
2097
2098 d = nfs_add_or_obtain(dentry, fhandle, fattr, label);
2099 if (IS_ERR(d))
2100 return PTR_ERR(d);
2101
2102
2103 dput(d);
2104 return 0;
2105}
2106EXPORT_SYMBOL_GPL(nfs_instantiate);
2107
2108
2109
2110
2111
2112
2113
2114int nfs_create(struct user_namespace *mnt_userns, struct inode *dir,
2115 struct dentry *dentry, umode_t mode, bool excl)
2116{
2117 struct iattr attr;
2118 int open_flags = excl ? O_CREAT | O_EXCL : O_CREAT;
2119 int error;
2120
2121 dfprintk(VFS, "NFS: create(%s/%lu), %pd\n",
2122 dir->i_sb->s_id, dir->i_ino, dentry);
2123
2124 attr.ia_mode = mode;
2125 attr.ia_valid = ATTR_MODE;
2126
2127 trace_nfs_create_enter(dir, dentry, open_flags);
2128 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags);
2129 trace_nfs_create_exit(dir, dentry, open_flags, error);
2130 if (error != 0)
2131 goto out_err;
2132 return 0;
2133out_err:
2134 d_drop(dentry);
2135 return error;
2136}
2137EXPORT_SYMBOL_GPL(nfs_create);
2138
2139
2140
2141
2142int
2143nfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
2144 struct dentry *dentry, umode_t mode, dev_t rdev)
2145{
2146 struct iattr attr;
2147 int status;
2148
2149 dfprintk(VFS, "NFS: mknod(%s/%lu), %pd\n",
2150 dir->i_sb->s_id, dir->i_ino, dentry);
2151
2152 attr.ia_mode = mode;
2153 attr.ia_valid = ATTR_MODE;
2154
2155 trace_nfs_mknod_enter(dir, dentry);
2156 status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
2157 trace_nfs_mknod_exit(dir, dentry, status);
2158 if (status != 0)
2159 goto out_err;
2160 return 0;
2161out_err:
2162 d_drop(dentry);
2163 return status;
2164}
2165EXPORT_SYMBOL_GPL(nfs_mknod);
2166
2167
2168
2169
2170int nfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
2171 struct dentry *dentry, umode_t mode)
2172{
2173 struct iattr attr;
2174 int error;
2175
2176 dfprintk(VFS, "NFS: mkdir(%s/%lu), %pd\n",
2177 dir->i_sb->s_id, dir->i_ino, dentry);
2178
2179 attr.ia_valid = ATTR_MODE;
2180 attr.ia_mode = mode | S_IFDIR;
2181
2182 trace_nfs_mkdir_enter(dir, dentry);
2183 error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
2184 trace_nfs_mkdir_exit(dir, dentry, error);
2185 if (error != 0)
2186 goto out_err;
2187 return 0;
2188out_err:
2189 d_drop(dentry);
2190 return error;
2191}
2192EXPORT_SYMBOL_GPL(nfs_mkdir);
2193
2194static void nfs_dentry_handle_enoent(struct dentry *dentry)
2195{
2196 if (simple_positive(dentry))
2197 d_delete(dentry);
2198}
2199
2200int nfs_rmdir(struct inode *dir, struct dentry *dentry)
2201{
2202 int error;
2203
2204 dfprintk(VFS, "NFS: rmdir(%s/%lu), %pd\n",
2205 dir->i_sb->s_id, dir->i_ino, dentry);
2206
2207 trace_nfs_rmdir_enter(dir, dentry);
2208 if (d_really_is_positive(dentry)) {
2209 down_write(&NFS_I(d_inode(dentry))->rmdir_sem);
2210 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
2211
2212 switch (error) {
2213 case 0:
2214 clear_nlink(d_inode(dentry));
2215 break;
2216 case -ENOENT:
2217 nfs_dentry_handle_enoent(dentry);
2218 }
2219 up_write(&NFS_I(d_inode(dentry))->rmdir_sem);
2220 } else
2221 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
2222 trace_nfs_rmdir_exit(dir, dentry, error);
2223
2224 return error;
2225}
2226EXPORT_SYMBOL_GPL(nfs_rmdir);
2227
2228
2229
2230
2231
2232
2233
2234
2235static int nfs_safe_remove(struct dentry *dentry)
2236{
2237 struct inode *dir = d_inode(dentry->d_parent);
2238 struct inode *inode = d_inode(dentry);
2239 int error = -EBUSY;
2240
2241 dfprintk(VFS, "NFS: safe_remove(%pd2)\n", dentry);
2242
2243
2244 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
2245 error = 0;
2246 goto out;
2247 }
2248
2249 trace_nfs_remove_enter(dir, dentry);
2250 if (inode != NULL) {
2251 error = NFS_PROTO(dir)->remove(dir, dentry);
2252 if (error == 0)
2253 nfs_drop_nlink(inode);
2254 } else
2255 error = NFS_PROTO(dir)->remove(dir, dentry);
2256 if (error == -ENOENT)
2257 nfs_dentry_handle_enoent(dentry);
2258 trace_nfs_remove_exit(dir, dentry, error);
2259out:
2260 return error;
2261}
2262
2263
2264
2265
2266
2267
2268int nfs_unlink(struct inode *dir, struct dentry *dentry)
2269{
2270 int error;
2271 int need_rehash = 0;
2272
2273 dfprintk(VFS, "NFS: unlink(%s/%lu, %pd)\n", dir->i_sb->s_id,
2274 dir->i_ino, dentry);
2275
2276 trace_nfs_unlink_enter(dir, dentry);
2277 spin_lock(&dentry->d_lock);
2278 if (d_count(dentry) > 1) {
2279 spin_unlock(&dentry->d_lock);
2280
2281 write_inode_now(d_inode(dentry), 0);
2282 error = nfs_sillyrename(dir, dentry);
2283 goto out;
2284 }
2285 if (!d_unhashed(dentry)) {
2286 __d_drop(dentry);
2287 need_rehash = 1;
2288 }
2289 spin_unlock(&dentry->d_lock);
2290 error = nfs_safe_remove(dentry);
2291 if (!error || error == -ENOENT) {
2292 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
2293 } else if (need_rehash)
2294 d_rehash(dentry);
2295out:
2296 trace_nfs_unlink_exit(dir, dentry, error);
2297 return error;
2298}
2299EXPORT_SYMBOL_GPL(nfs_unlink);
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316int nfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
2317 struct dentry *dentry, const char *symname)
2318{
2319 struct page *page;
2320 char *kaddr;
2321 struct iattr attr;
2322 unsigned int pathlen = strlen(symname);
2323 int error;
2324
2325 dfprintk(VFS, "NFS: symlink(%s/%lu, %pd, %s)\n", dir->i_sb->s_id,
2326 dir->i_ino, dentry, symname);
2327
2328 if (pathlen > PAGE_SIZE)
2329 return -ENAMETOOLONG;
2330
2331 attr.ia_mode = S_IFLNK | S_IRWXUGO;
2332 attr.ia_valid = ATTR_MODE;
2333
2334 page = alloc_page(GFP_USER);
2335 if (!page)
2336 return -ENOMEM;
2337
2338 kaddr = page_address(page);
2339 memcpy(kaddr, symname, pathlen);
2340 if (pathlen < PAGE_SIZE)
2341 memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
2342
2343 trace_nfs_symlink_enter(dir, dentry);
2344 error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
2345 trace_nfs_symlink_exit(dir, dentry, error);
2346 if (error != 0) {
2347 dfprintk(VFS, "NFS: symlink(%s/%lu, %pd, %s) error %d\n",
2348 dir->i_sb->s_id, dir->i_ino,
2349 dentry, symname, error);
2350 d_drop(dentry);
2351 __free_page(page);
2352 return error;
2353 }
2354
2355
2356
2357
2358
2359 if (!add_to_page_cache_lru(page, d_inode(dentry)->i_mapping, 0,
2360 GFP_KERNEL)) {
2361 SetPageUptodate(page);
2362 unlock_page(page);
2363
2364
2365
2366
2367 put_page(page);
2368 } else
2369 __free_page(page);
2370
2371 return 0;
2372}
2373EXPORT_SYMBOL_GPL(nfs_symlink);
2374
2375int
2376nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
2377{
2378 struct inode *inode = d_inode(old_dentry);
2379 int error;
2380
2381 dfprintk(VFS, "NFS: link(%pd2 -> %pd2)\n",
2382 old_dentry, dentry);
2383
2384 trace_nfs_link_enter(inode, dir, dentry);
2385 d_drop(dentry);
2386 error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
2387 if (error == 0) {
2388 ihold(inode);
2389 d_add(dentry, inode);
2390 }
2391 trace_nfs_link_exit(inode, dir, dentry, error);
2392 return error;
2393}
2394EXPORT_SYMBOL_GPL(nfs_link);
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420int nfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
2421 struct dentry *old_dentry, struct inode *new_dir,
2422 struct dentry *new_dentry, unsigned int flags)
2423{
2424 struct inode *old_inode = d_inode(old_dentry);
2425 struct inode *new_inode = d_inode(new_dentry);
2426 struct dentry *dentry = NULL, *rehash = NULL;
2427 struct rpc_task *task;
2428 int error = -EBUSY;
2429
2430 if (flags)
2431 return -EINVAL;
2432
2433 dfprintk(VFS, "NFS: rename(%pd2 -> %pd2, ct=%d)\n",
2434 old_dentry, new_dentry,
2435 d_count(new_dentry));
2436
2437 trace_nfs_rename_enter(old_dir, old_dentry, new_dir, new_dentry);
2438
2439
2440
2441
2442
2443
2444 if (new_inode && !S_ISDIR(new_inode->i_mode)) {
2445
2446
2447
2448
2449 if (!d_unhashed(new_dentry)) {
2450 d_drop(new_dentry);
2451 rehash = new_dentry;
2452 }
2453
2454 if (d_count(new_dentry) > 2) {
2455 int err;
2456
2457
2458 dentry = d_alloc(new_dentry->d_parent,
2459 &new_dentry->d_name);
2460 if (!dentry)
2461 goto out;
2462
2463
2464 err = nfs_sillyrename(new_dir, new_dentry);
2465 if (err)
2466 goto out;
2467
2468 new_dentry = dentry;
2469 rehash = NULL;
2470 new_inode = NULL;
2471 }
2472 }
2473
2474 task = nfs_async_rename(old_dir, new_dir, old_dentry, new_dentry, NULL);
2475 if (IS_ERR(task)) {
2476 error = PTR_ERR(task);
2477 goto out;
2478 }
2479
2480 error = rpc_wait_for_completion_task(task);
2481 if (error != 0) {
2482 ((struct nfs_renamedata *)task->tk_calldata)->cancelled = 1;
2483
2484 smp_wmb();
2485 } else
2486 error = task->tk_status;
2487 rpc_put_task(task);
2488
2489 if (error == 0) {
2490 spin_lock(&old_inode->i_lock);
2491 NFS_I(old_inode)->attr_gencount = nfs_inc_attr_generation_counter();
2492 nfs_set_cache_invalid(old_inode, NFS_INO_INVALID_CHANGE |
2493 NFS_INO_INVALID_CTIME |
2494 NFS_INO_REVAL_FORCED);
2495 spin_unlock(&old_inode->i_lock);
2496 }
2497out:
2498 if (rehash)
2499 d_rehash(rehash);
2500 trace_nfs_rename_exit(old_dir, old_dentry,
2501 new_dir, new_dentry, error);
2502 if (!error) {
2503 if (new_inode != NULL)
2504 nfs_drop_nlink(new_inode);
2505
2506
2507
2508
2509
2510
2511 d_move(old_dentry, new_dentry);
2512 nfs_set_verifier(old_dentry,
2513 nfs_save_change_attribute(new_dir));
2514 } else if (error == -ENOENT)
2515 nfs_dentry_handle_enoent(old_dentry);
2516
2517
2518 if (dentry)
2519 dput(dentry);
2520 return error;
2521}
2522EXPORT_SYMBOL_GPL(nfs_rename);
2523
2524static DEFINE_SPINLOCK(nfs_access_lru_lock);
2525static LIST_HEAD(nfs_access_lru_list);
2526static atomic_long_t nfs_access_nr_entries;
2527
2528static unsigned long nfs_access_max_cachesize = 4*1024*1024;
2529module_param(nfs_access_max_cachesize, ulong, 0644);
2530MODULE_PARM_DESC(nfs_access_max_cachesize, "NFS access maximum total cache length");
2531
2532static void nfs_access_free_entry(struct nfs_access_entry *entry)
2533{
2534 put_cred(entry->cred);
2535 kfree_rcu(entry, rcu_head);
2536 smp_mb__before_atomic();
2537 atomic_long_dec(&nfs_access_nr_entries);
2538 smp_mb__after_atomic();
2539}
2540
2541static void nfs_access_free_list(struct list_head *head)
2542{
2543 struct nfs_access_entry *cache;
2544
2545 while (!list_empty(head)) {
2546 cache = list_entry(head->next, struct nfs_access_entry, lru);
2547 list_del(&cache->lru);
2548 nfs_access_free_entry(cache);
2549 }
2550}
2551
2552static unsigned long
2553nfs_do_access_cache_scan(unsigned int nr_to_scan)
2554{
2555 LIST_HEAD(head);
2556 struct nfs_inode *nfsi, *next;
2557 struct nfs_access_entry *cache;
2558 long freed = 0;
2559
2560 spin_lock(&nfs_access_lru_lock);
2561 list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
2562 struct inode *inode;
2563
2564 if (nr_to_scan-- == 0)
2565 break;
2566 inode = &nfsi->vfs_inode;
2567 spin_lock(&inode->i_lock);
2568 if (list_empty(&nfsi->access_cache_entry_lru))
2569 goto remove_lru_entry;
2570 cache = list_entry(nfsi->access_cache_entry_lru.next,
2571 struct nfs_access_entry, lru);
2572 list_move(&cache->lru, &head);
2573 rb_erase(&cache->rb_node, &nfsi->access_cache);
2574 freed++;
2575 if (!list_empty(&nfsi->access_cache_entry_lru))
2576 list_move_tail(&nfsi->access_cache_inode_lru,
2577 &nfs_access_lru_list);
2578 else {
2579remove_lru_entry:
2580 list_del_init(&nfsi->access_cache_inode_lru);
2581 smp_mb__before_atomic();
2582 clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
2583 smp_mb__after_atomic();
2584 }
2585 spin_unlock(&inode->i_lock);
2586 }
2587 spin_unlock(&nfs_access_lru_lock);
2588 nfs_access_free_list(&head);
2589 return freed;
2590}
2591
2592unsigned long
2593nfs_access_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
2594{
2595 int nr_to_scan = sc->nr_to_scan;
2596 gfp_t gfp_mask = sc->gfp_mask;
2597
2598 if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
2599 return SHRINK_STOP;
2600 return nfs_do_access_cache_scan(nr_to_scan);
2601}
2602
2603
2604unsigned long
2605nfs_access_cache_count(struct shrinker *shrink, struct shrink_control *sc)
2606{
2607 return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries));
2608}
2609
2610static void
2611nfs_access_cache_enforce_limit(void)
2612{
2613 long nr_entries = atomic_long_read(&nfs_access_nr_entries);
2614 unsigned long diff;
2615 unsigned int nr_to_scan;
2616
2617 if (nr_entries < 0 || nr_entries <= nfs_access_max_cachesize)
2618 return;
2619 nr_to_scan = 100;
2620 diff = nr_entries - nfs_access_max_cachesize;
2621 if (diff < nr_to_scan)
2622 nr_to_scan = diff;
2623 nfs_do_access_cache_scan(nr_to_scan);
2624}
2625
2626static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
2627{
2628 struct rb_root *root_node = &nfsi->access_cache;
2629 struct rb_node *n;
2630 struct nfs_access_entry *entry;
2631
2632
2633 while ((n = rb_first(root_node)) != NULL) {
2634 entry = rb_entry(n, struct nfs_access_entry, rb_node);
2635 rb_erase(n, root_node);
2636 list_move(&entry->lru, head);
2637 }
2638 nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
2639}
2640
2641void nfs_access_zap_cache(struct inode *inode)
2642{
2643 LIST_HEAD(head);
2644
2645 if (test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags) == 0)
2646 return;
2647
2648 spin_lock(&nfs_access_lru_lock);
2649 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
2650 list_del_init(&NFS_I(inode)->access_cache_inode_lru);
2651
2652 spin_lock(&inode->i_lock);
2653 __nfs_access_zap_cache(NFS_I(inode), &head);
2654 spin_unlock(&inode->i_lock);
2655 spin_unlock(&nfs_access_lru_lock);
2656 nfs_access_free_list(&head);
2657}
2658EXPORT_SYMBOL_GPL(nfs_access_zap_cache);
2659
2660static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, const struct cred *cred)
2661{
2662 struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
2663
2664 while (n != NULL) {
2665 struct nfs_access_entry *entry =
2666 rb_entry(n, struct nfs_access_entry, rb_node);
2667 int cmp = cred_fscmp(cred, entry->cred);
2668
2669 if (cmp < 0)
2670 n = n->rb_left;
2671 else if (cmp > 0)
2672 n = n->rb_right;
2673 else
2674 return entry;
2675 }
2676 return NULL;
2677}
2678
2679static int nfs_access_get_cached_locked(struct inode *inode, const struct cred *cred, struct nfs_access_entry *res, bool may_block)
2680{
2681 struct nfs_inode *nfsi = NFS_I(inode);
2682 struct nfs_access_entry *cache;
2683 bool retry = true;
2684 int err;
2685
2686 spin_lock(&inode->i_lock);
2687 for(;;) {
2688 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
2689 goto out_zap;
2690 cache = nfs_access_search_rbtree(inode, cred);
2691 err = -ENOENT;
2692 if (cache == NULL)
2693 goto out;
2694
2695 if (!nfs_check_cache_invalid(inode, NFS_INO_INVALID_ACCESS))
2696 break;
2697 if (!retry)
2698 break;
2699 err = -ECHILD;
2700 if (!may_block)
2701 goto out;
2702 spin_unlock(&inode->i_lock);
2703 err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
2704 if (err)
2705 return err;
2706 spin_lock(&inode->i_lock);
2707 retry = false;
2708 }
2709 res->cred = cache->cred;
2710 res->mask = cache->mask;
2711 list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
2712 err = 0;
2713out:
2714 spin_unlock(&inode->i_lock);
2715 return err;
2716out_zap:
2717 spin_unlock(&inode->i_lock);
2718 nfs_access_zap_cache(inode);
2719 return -ENOENT;
2720}
2721
2722static int nfs_access_get_cached_rcu(struct inode *inode, const struct cred *cred, struct nfs_access_entry *res)
2723{
2724
2725
2726
2727 struct nfs_inode *nfsi = NFS_I(inode);
2728 struct nfs_access_entry *cache;
2729 int err = -ECHILD;
2730 struct list_head *lh;
2731
2732 rcu_read_lock();
2733 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
2734 goto out;
2735 lh = rcu_dereference(list_tail_rcu(&nfsi->access_cache_entry_lru));
2736 cache = list_entry(lh, struct nfs_access_entry, lru);
2737 if (lh == &nfsi->access_cache_entry_lru ||
2738 cred_fscmp(cred, cache->cred) != 0)
2739 cache = NULL;
2740 if (cache == NULL)
2741 goto out;
2742 if (nfs_check_cache_invalid(inode, NFS_INO_INVALID_ACCESS))
2743 goto out;
2744 res->cred = cache->cred;
2745 res->mask = cache->mask;
2746 err = 0;
2747out:
2748 rcu_read_unlock();
2749 return err;
2750}
2751
2752int nfs_access_get_cached(struct inode *inode, const struct cred *cred, struct
2753nfs_access_entry *res, bool may_block)
2754{
2755 int status;
2756
2757 status = nfs_access_get_cached_rcu(inode, cred, res);
2758 if (status != 0)
2759 status = nfs_access_get_cached_locked(inode, cred, res,
2760 may_block);
2761
2762 return status;
2763}
2764EXPORT_SYMBOL_GPL(nfs_access_get_cached);
2765
2766static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
2767{
2768 struct nfs_inode *nfsi = NFS_I(inode);
2769 struct rb_root *root_node = &nfsi->access_cache;
2770 struct rb_node **p = &root_node->rb_node;
2771 struct rb_node *parent = NULL;
2772 struct nfs_access_entry *entry;
2773 int cmp;
2774
2775 spin_lock(&inode->i_lock);
2776 while (*p != NULL) {
2777 parent = *p;
2778 entry = rb_entry(parent, struct nfs_access_entry, rb_node);
2779 cmp = cred_fscmp(set->cred, entry->cred);
2780
2781 if (cmp < 0)
2782 p = &parent->rb_left;
2783 else if (cmp > 0)
2784 p = &parent->rb_right;
2785 else
2786 goto found;
2787 }
2788 rb_link_node(&set->rb_node, parent, p);
2789 rb_insert_color(&set->rb_node, root_node);
2790 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
2791 spin_unlock(&inode->i_lock);
2792 return;
2793found:
2794 rb_replace_node(parent, &set->rb_node, root_node);
2795 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
2796 list_del(&entry->lru);
2797 spin_unlock(&inode->i_lock);
2798 nfs_access_free_entry(entry);
2799}
2800
2801void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
2802{
2803 struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
2804 if (cache == NULL)
2805 return;
2806 RB_CLEAR_NODE(&cache->rb_node);
2807 cache->cred = get_cred(set->cred);
2808 cache->mask = set->mask;
2809
2810
2811
2812
2813
2814 smp_wmb();
2815 nfs_access_add_rbtree(inode, cache);
2816
2817
2818 smp_mb__before_atomic();
2819 atomic_long_inc(&nfs_access_nr_entries);
2820 smp_mb__after_atomic();
2821
2822
2823 if (!test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags)) {
2824 spin_lock(&nfs_access_lru_lock);
2825 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
2826 list_add_tail(&NFS_I(inode)->access_cache_inode_lru,
2827 &nfs_access_lru_list);
2828 spin_unlock(&nfs_access_lru_lock);
2829 }
2830 nfs_access_cache_enforce_limit();
2831}
2832EXPORT_SYMBOL_GPL(nfs_access_add_cache);
2833
2834#define NFS_MAY_READ (NFS_ACCESS_READ)
2835#define NFS_MAY_WRITE (NFS_ACCESS_MODIFY | \
2836 NFS_ACCESS_EXTEND | \
2837 NFS_ACCESS_DELETE)
2838#define NFS_FILE_MAY_WRITE (NFS_ACCESS_MODIFY | \
2839 NFS_ACCESS_EXTEND)
2840#define NFS_DIR_MAY_WRITE NFS_MAY_WRITE
2841#define NFS_MAY_LOOKUP (NFS_ACCESS_LOOKUP)
2842#define NFS_MAY_EXECUTE (NFS_ACCESS_EXECUTE)
2843static int
2844nfs_access_calc_mask(u32 access_result, umode_t umode)
2845{
2846 int mask = 0;
2847
2848 if (access_result & NFS_MAY_READ)
2849 mask |= MAY_READ;
2850 if (S_ISDIR(umode)) {
2851 if ((access_result & NFS_DIR_MAY_WRITE) == NFS_DIR_MAY_WRITE)
2852 mask |= MAY_WRITE;
2853 if ((access_result & NFS_MAY_LOOKUP) == NFS_MAY_LOOKUP)
2854 mask |= MAY_EXEC;
2855 } else if (S_ISREG(umode)) {
2856 if ((access_result & NFS_FILE_MAY_WRITE) == NFS_FILE_MAY_WRITE)
2857 mask |= MAY_WRITE;
2858 if ((access_result & NFS_MAY_EXECUTE) == NFS_MAY_EXECUTE)
2859 mask |= MAY_EXEC;
2860 } else if (access_result & NFS_MAY_WRITE)
2861 mask |= MAY_WRITE;
2862 return mask;
2863}
2864
2865void nfs_access_set_mask(struct nfs_access_entry *entry, u32 access_result)
2866{
2867 entry->mask = access_result;
2868}
2869EXPORT_SYMBOL_GPL(nfs_access_set_mask);
2870
2871static int nfs_do_access(struct inode *inode, const struct cred *cred, int mask)
2872{
2873 struct nfs_access_entry cache;
2874 bool may_block = (mask & MAY_NOT_BLOCK) == 0;
2875 int cache_mask = -1;
2876 int status;
2877
2878 trace_nfs_access_enter(inode);
2879
2880 status = nfs_access_get_cached(inode, cred, &cache, may_block);
2881 if (status == 0)
2882 goto out_cached;
2883
2884 status = -ECHILD;
2885 if (!may_block)
2886 goto out;
2887
2888
2889
2890
2891 cache.mask = NFS_ACCESS_READ | NFS_ACCESS_MODIFY | NFS_ACCESS_EXTEND;
2892 if (nfs_server_capable(inode, NFS_CAP_XATTR)) {
2893 cache.mask |= NFS_ACCESS_XAREAD | NFS_ACCESS_XAWRITE |
2894 NFS_ACCESS_XALIST;
2895 }
2896 if (S_ISDIR(inode->i_mode))
2897 cache.mask |= NFS_ACCESS_DELETE | NFS_ACCESS_LOOKUP;
2898 else
2899 cache.mask |= NFS_ACCESS_EXECUTE;
2900 cache.cred = cred;
2901 status = NFS_PROTO(inode)->access(inode, &cache);
2902 if (status != 0) {
2903 if (status == -ESTALE) {
2904 if (!S_ISDIR(inode->i_mode))
2905 nfs_set_inode_stale(inode);
2906 else
2907 nfs_zap_caches(inode);
2908 }
2909 goto out;
2910 }
2911 nfs_access_add_cache(inode, &cache);
2912out_cached:
2913 cache_mask = nfs_access_calc_mask(cache.mask, inode->i_mode);
2914 if ((mask & ~cache_mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) != 0)
2915 status = -EACCES;
2916out:
2917 trace_nfs_access_exit(inode, mask, cache_mask, status);
2918 return status;
2919}
2920
2921static int nfs_open_permission_mask(int openflags)
2922{
2923 int mask = 0;
2924
2925 if (openflags & __FMODE_EXEC) {
2926
2927 mask = MAY_EXEC;
2928 } else {
2929 if ((openflags & O_ACCMODE) != O_WRONLY)
2930 mask |= MAY_READ;
2931 if ((openflags & O_ACCMODE) != O_RDONLY)
2932 mask |= MAY_WRITE;
2933 }
2934
2935 return mask;
2936}
2937
2938int nfs_may_open(struct inode *inode, const struct cred *cred, int openflags)
2939{
2940 return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
2941}
2942EXPORT_SYMBOL_GPL(nfs_may_open);
2943
2944static int nfs_execute_ok(struct inode *inode, int mask)
2945{
2946 struct nfs_server *server = NFS_SERVER(inode);
2947 int ret = 0;
2948
2949 if (S_ISDIR(inode->i_mode))
2950 return 0;
2951 if (nfs_check_cache_invalid(inode, NFS_INO_INVALID_MODE)) {
2952 if (mask & MAY_NOT_BLOCK)
2953 return -ECHILD;
2954 ret = __nfs_revalidate_inode(server, inode);
2955 }
2956 if (ret == 0 && !execute_ok(inode))
2957 ret = -EACCES;
2958 return ret;
2959}
2960
2961int nfs_permission(struct user_namespace *mnt_userns,
2962 struct inode *inode,
2963 int mask)
2964{
2965 const struct cred *cred = current_cred();
2966 int res = 0;
2967
2968 nfs_inc_stats(inode, NFSIOS_VFSACCESS);
2969
2970 if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
2971 goto out;
2972
2973 if (mask & (MAY_ACCESS | MAY_CHDIR))
2974 goto force_lookup;
2975
2976 switch (inode->i_mode & S_IFMT) {
2977 case S_IFLNK:
2978 goto out;
2979 case S_IFREG:
2980 if ((mask & MAY_OPEN) &&
2981 nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN))
2982 return 0;
2983 break;
2984 case S_IFDIR:
2985
2986
2987
2988
2989 if ((mask & MAY_WRITE) && !(mask & MAY_READ))
2990 goto out;
2991 }
2992
2993force_lookup:
2994 if (!NFS_PROTO(inode)->access)
2995 goto out_notsup;
2996
2997 res = nfs_do_access(inode, cred, mask);
2998out:
2999 if (!res && (mask & MAY_EXEC))
3000 res = nfs_execute_ok(inode, mask);
3001
3002 dfprintk(VFS, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n",
3003 inode->i_sb->s_id, inode->i_ino, mask, res);
3004 return res;
3005out_notsup:
3006 if (mask & MAY_NOT_BLOCK)
3007 return -ECHILD;
3008
3009 res = nfs_revalidate_inode(inode, NFS_INO_INVALID_MODE |
3010 NFS_INO_INVALID_OTHER);
3011 if (res == 0)
3012 res = generic_permission(&init_user_ns, inode, mask);
3013 goto out;
3014}
3015EXPORT_SYMBOL_GPL(nfs_permission);
3016