xref: /openbmc/linux/fs/afs/dir.c (revision efb339a83368ab25de1a18c0fdff85e01c13a1ea)
1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /* dir.c: AFS filesystem directory handling
3   *
4   * Copyright (C) 2002, 2018 Red Hat, Inc. All Rights Reserved.
5   * Written by David Howells (dhowells@redhat.com)
6   */
7  
8  #include <linux/kernel.h>
9  #include <linux/fs.h>
10  #include <linux/namei.h>
11  #include <linux/pagemap.h>
12  #include <linux/swap.h>
13  #include <linux/ctype.h>
14  #include <linux/sched.h>
15  #include <linux/task_io_accounting_ops.h>
16  #include "internal.h"
17  #include "afs_fs.h"
18  #include "xdr_fs.h"
19  
20  static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
21  				 unsigned int flags);
22  static int afs_dir_open(struct inode *inode, struct file *file);
23  static int afs_readdir(struct file *file, struct dir_context *ctx);
24  static int afs_d_revalidate(struct dentry *dentry, unsigned int flags);
25  static int afs_d_delete(const struct dentry *dentry);
26  static void afs_d_iput(struct dentry *dentry, struct inode *inode);
27  static bool afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen,
28  				  loff_t fpos, u64 ino, unsigned dtype);
29  static bool afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen,
30  			      loff_t fpos, u64 ino, unsigned dtype);
31  static int afs_create(struct mnt_idmap *idmap, struct inode *dir,
32  		      struct dentry *dentry, umode_t mode, bool excl);
33  static int afs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
34  		     struct dentry *dentry, umode_t mode);
35  static int afs_rmdir(struct inode *dir, struct dentry *dentry);
36  static int afs_unlink(struct inode *dir, struct dentry *dentry);
37  static int afs_link(struct dentry *from, struct inode *dir,
38  		    struct dentry *dentry);
39  static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
40  		       struct dentry *dentry, const char *content);
41  static int afs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
42  		      struct dentry *old_dentry, struct inode *new_dir,
43  		      struct dentry *new_dentry, unsigned int flags);
44  static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags);
45  static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
46  				   size_t length);
47  
48  static bool afs_dir_dirty_folio(struct address_space *mapping,
49  		struct folio *folio)
50  {
51  	BUG(); /* This should never happen. */
52  }
53  
54  const struct file_operations afs_dir_file_operations = {
55  	.open		= afs_dir_open,
56  	.release	= afs_release,
57  	.iterate_shared	= afs_readdir,
58  	.lock		= afs_lock,
59  	.llseek		= generic_file_llseek,
60  };
61  
62  const struct inode_operations afs_dir_inode_operations = {
63  	.create		= afs_create,
64  	.lookup		= afs_lookup,
65  	.link		= afs_link,
66  	.unlink		= afs_unlink,
67  	.symlink	= afs_symlink,
68  	.mkdir		= afs_mkdir,
69  	.rmdir		= afs_rmdir,
70  	.rename		= afs_rename,
71  	.permission	= afs_permission,
72  	.getattr	= afs_getattr,
73  	.setattr	= afs_setattr,
74  };
75  
76  const struct address_space_operations afs_dir_aops = {
77  	.dirty_folio	= afs_dir_dirty_folio,
78  	.release_folio	= afs_dir_release_folio,
79  	.invalidate_folio = afs_dir_invalidate_folio,
80  	.migrate_folio	= filemap_migrate_folio,
81  };
82  
83  const struct dentry_operations afs_fs_dentry_operations = {
84  	.d_revalidate	= afs_d_revalidate,
85  	.d_delete	= afs_d_delete,
86  	.d_release	= afs_d_release,
87  	.d_automount	= afs_d_automount,
88  	.d_iput		= afs_d_iput,
89  };
90  
91  struct afs_lookup_one_cookie {
92  	struct dir_context	ctx;
93  	struct qstr		name;
94  	bool			found;
95  	struct afs_fid		fid;
96  };
97  
98  struct afs_lookup_cookie {
99  	struct dir_context	ctx;
100  	struct qstr		name;
101  	bool			found;
102  	bool			one_only;
103  	unsigned short		nr_fids;
104  	struct afs_fid		fids[50];
105  };
106  
107  /*
108   * Drop the refs that we're holding on the folios we were reading into.  We've
109   * got refs on the first nr_pages pages.
110   */
111  static void afs_dir_read_cleanup(struct afs_read *req)
112  {
113  	struct address_space *mapping = req->vnode->netfs.inode.i_mapping;
114  	struct folio *folio;
115  	pgoff_t last = req->nr_pages - 1;
116  
117  	XA_STATE(xas, &mapping->i_pages, 0);
118  
119  	if (unlikely(!req->nr_pages))
120  		return;
121  
122  	rcu_read_lock();
123  	xas_for_each(&xas, folio, last) {
124  		if (xas_retry(&xas, folio))
125  			continue;
126  		BUG_ON(xa_is_value(folio));
127  		ASSERTCMP(folio_file_mapping(folio), ==, mapping);
128  
129  		folio_put(folio);
130  	}
131  
132  	rcu_read_unlock();
133  }
134  
135  /*
136   * check that a directory folio is valid
137   */
138  static bool afs_dir_check_folio(struct afs_vnode *dvnode, struct folio *folio,
139  				loff_t i_size)
140  {
141  	union afs_xdr_dir_block *block;
142  	size_t offset, size;
143  	loff_t pos;
144  
145  	/* Determine how many magic numbers there should be in this folio, but
146  	 * we must take care because the directory may change size under us.
147  	 */
148  	pos = folio_pos(folio);
149  	if (i_size <= pos)
150  		goto checked;
151  
152  	size = min_t(loff_t, folio_size(folio), i_size - pos);
153  	for (offset = 0; offset < size; offset += sizeof(*block)) {
154  		block = kmap_local_folio(folio, offset);
155  		if (block->hdr.magic != AFS_DIR_MAGIC) {
156  			printk("kAFS: %s(%lx): [%llx] bad magic %zx/%zx is %04hx\n",
157  			       __func__, dvnode->netfs.inode.i_ino,
158  			       pos, offset, size, ntohs(block->hdr.magic));
159  			trace_afs_dir_check_failed(dvnode, pos + offset, i_size);
160  			kunmap_local(block);
161  			trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
162  			goto error;
163  		}
164  
165  		/* Make sure each block is NUL terminated so we can reasonably
166  		 * use string functions on it.  The filenames in the folio
167  		 * *should* be NUL-terminated anyway.
168  		 */
169  		((u8 *)block)[AFS_DIR_BLOCK_SIZE - 1] = 0;
170  
171  		kunmap_local(block);
172  	}
173  checked:
174  	afs_stat_v(dvnode, n_read_dir);
175  	return true;
176  
177  error:
178  	return false;
179  }
180  
181  /*
182   * Dump the contents of a directory.
183   */
184  static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req)
185  {
186  	union afs_xdr_dir_block *block;
187  	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
188  	struct folio *folio;
189  	pgoff_t last = req->nr_pages - 1;
190  	size_t offset, size;
191  
192  	XA_STATE(xas, &mapping->i_pages, 0);
193  
194  	pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx\n",
195  		dvnode->fid.vid, dvnode->fid.vnode,
196  		req->file_size, req->len, req->actual_len);
197  	pr_warn("DIR %llx %x %zx %zx\n",
198  		req->pos, req->nr_pages,
199  		req->iter->iov_offset,  iov_iter_count(req->iter));
200  
201  	xas_for_each(&xas, folio, last) {
202  		if (xas_retry(&xas, folio))
203  			continue;
204  
205  		BUG_ON(folio_file_mapping(folio) != mapping);
206  
207  		size = min_t(loff_t, folio_size(folio), req->actual_len - folio_pos(folio));
208  		for (offset = 0; offset < size; offset += sizeof(*block)) {
209  			block = kmap_local_folio(folio, offset);
210  			pr_warn("[%02lx] %32phN\n", folio_index(folio) + offset, block);
211  			kunmap_local(block);
212  		}
213  	}
214  }
215  
216  /*
217   * Check all the blocks in a directory.  All the folios are held pinned.
218   */
219  static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req)
220  {
221  	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
222  	struct folio *folio;
223  	pgoff_t last = req->nr_pages - 1;
224  	int ret = 0;
225  
226  	XA_STATE(xas, &mapping->i_pages, 0);
227  
228  	if (unlikely(!req->nr_pages))
229  		return 0;
230  
231  	rcu_read_lock();
232  	xas_for_each(&xas, folio, last) {
233  		if (xas_retry(&xas, folio))
234  			continue;
235  
236  		BUG_ON(folio_file_mapping(folio) != mapping);
237  
238  		if (!afs_dir_check_folio(dvnode, folio, req->actual_len)) {
239  			afs_dir_dump(dvnode, req);
240  			ret = -EIO;
241  			break;
242  		}
243  	}
244  
245  	rcu_read_unlock();
246  	return ret;
247  }
248  
249  /*
250   * open an AFS directory file
251   */
252  static int afs_dir_open(struct inode *inode, struct file *file)
253  {
254  	_enter("{%lu}", inode->i_ino);
255  
256  	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
257  	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
258  
259  	if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
260  		return -ENOENT;
261  
262  	return afs_open(inode, file);
263  }
264  
265  /*
266   * Read the directory into the pagecache in one go, scrubbing the previous
267   * contents.  The list of folios is returned, pinning them so that they don't
268   * get reclaimed during the iteration.
269   */
270  static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
271  	__acquires(&dvnode->validate_lock)
272  {
273  	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
274  	struct afs_read *req;
275  	loff_t i_size;
276  	int nr_pages, i;
277  	int ret;
278  
279  	_enter("");
280  
281  	req = kzalloc(sizeof(*req), GFP_KERNEL);
282  	if (!req)
283  		return ERR_PTR(-ENOMEM);
284  
285  	refcount_set(&req->usage, 1);
286  	req->vnode = dvnode;
287  	req->key = key_get(key);
288  	req->cleanup = afs_dir_read_cleanup;
289  
290  expand:
291  	i_size = i_size_read(&dvnode->netfs.inode);
292  	if (i_size < 2048) {
293  		ret = afs_bad(dvnode, afs_file_error_dir_small);
294  		goto error;
295  	}
296  	if (i_size > 2048 * 1024) {
297  		trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
298  		ret = -EFBIG;
299  		goto error;
300  	}
301  
302  	_enter("%llu", i_size);
303  
304  	nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE;
305  
306  	req->actual_len = i_size; /* May change */
307  	req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
308  	req->data_version = dvnode->status.data_version; /* May change */
309  	iov_iter_xarray(&req->def_iter, ITER_DEST, &dvnode->netfs.inode.i_mapping->i_pages,
310  			0, i_size);
311  	req->iter = &req->def_iter;
312  
313  	/* Fill in any gaps that we might find where the memory reclaimer has
314  	 * been at work and pin all the folios.  If there are any gaps, we will
315  	 * need to reread the entire directory contents.
316  	 */
317  	i = req->nr_pages;
318  	while (i < nr_pages) {
319  		struct folio *folio;
320  
321  		folio = filemap_get_folio(mapping, i);
322  		if (!folio) {
323  			if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
324  				afs_stat_v(dvnode, n_inval);
325  
326  			ret = -ENOMEM;
327  			folio = __filemap_get_folio(mapping,
328  						    i, FGP_LOCK | FGP_CREAT,
329  						    mapping->gfp_mask);
330  			if (!folio)
331  				goto error;
332  			folio_attach_private(folio, (void *)1);
333  			folio_unlock(folio);
334  		}
335  
336  		req->nr_pages += folio_nr_pages(folio);
337  		i += folio_nr_pages(folio);
338  	}
339  
340  	/* If we're going to reload, we need to lock all the pages to prevent
341  	 * races.
342  	 */
343  	ret = -ERESTARTSYS;
344  	if (down_read_killable(&dvnode->validate_lock) < 0)
345  		goto error;
346  
347  	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
348  		goto success;
349  
350  	up_read(&dvnode->validate_lock);
351  	if (down_write_killable(&dvnode->validate_lock) < 0)
352  		goto error;
353  
354  	if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
355  		trace_afs_reload_dir(dvnode);
356  		ret = afs_fetch_data(dvnode, req);
357  		if (ret < 0)
358  			goto error_unlock;
359  
360  		task_io_account_read(PAGE_SIZE * req->nr_pages);
361  
362  		if (req->len < req->file_size) {
363  			/* The content has grown, so we need to expand the
364  			 * buffer.
365  			 */
366  			up_write(&dvnode->validate_lock);
367  			goto expand;
368  		}
369  
370  		/* Validate the data we just read. */
371  		ret = afs_dir_check(dvnode, req);
372  		if (ret < 0)
373  			goto error_unlock;
374  
375  		// TODO: Trim excess pages
376  
377  		set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags);
378  	}
379  
380  	downgrade_write(&dvnode->validate_lock);
381  success:
382  	return req;
383  
384  error_unlock:
385  	up_write(&dvnode->validate_lock);
386  error:
387  	afs_put_read(req);
388  	_leave(" = %d", ret);
389  	return ERR_PTR(ret);
390  }
391  
392  /*
393   * deal with one block in an AFS directory
394   */
395  static int afs_dir_iterate_block(struct afs_vnode *dvnode,
396  				 struct dir_context *ctx,
397  				 union afs_xdr_dir_block *block,
398  				 unsigned blkoff)
399  {
400  	union afs_xdr_dirent *dire;
401  	unsigned offset, next, curr, nr_slots;
402  	size_t nlen;
403  	int tmp;
404  
405  	_enter("%llx,%x", ctx->pos, blkoff);
406  
407  	curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
408  
409  	/* walk through the block, an entry at a time */
410  	for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
411  	     offset < AFS_DIR_SLOTS_PER_BLOCK;
412  	     offset = next
413  	     ) {
414  		/* skip entries marked unused in the bitmap */
415  		if (!(block->hdr.bitmap[offset / 8] &
416  		      (1 << (offset % 8)))) {
417  			_debug("ENT[%zu.%u]: unused",
418  			       blkoff / sizeof(union afs_xdr_dir_block), offset);
419  			next = offset + 1;
420  			if (offset >= curr)
421  				ctx->pos = blkoff +
422  					next * sizeof(union afs_xdr_dirent);
423  			continue;
424  		}
425  
426  		/* got a valid entry */
427  		dire = &block->dirents[offset];
428  		nlen = strnlen(dire->u.name,
429  			       sizeof(*block) -
430  			       offset * sizeof(union afs_xdr_dirent));
431  		if (nlen > AFSNAMEMAX - 1) {
432  			_debug("ENT[%zu]: name too long (len %u/%zu)",
433  			       blkoff / sizeof(union afs_xdr_dir_block),
434  			       offset, nlen);
435  			return afs_bad(dvnode, afs_file_error_dir_name_too_long);
436  		}
437  
438  		_debug("ENT[%zu.%u]: %s %zu \"%s\"",
439  		       blkoff / sizeof(union afs_xdr_dir_block), offset,
440  		       (offset < curr ? "skip" : "fill"),
441  		       nlen, dire->u.name);
442  
443  		nr_slots = afs_dir_calc_slots(nlen);
444  		next = offset + nr_slots;
445  		if (next > AFS_DIR_SLOTS_PER_BLOCK) {
446  			_debug("ENT[%zu.%u]:"
447  			       " %u extends beyond end dir block"
448  			       " (len %zu)",
449  			       blkoff / sizeof(union afs_xdr_dir_block),
450  			       offset, next, nlen);
451  			return afs_bad(dvnode, afs_file_error_dir_over_end);
452  		}
453  
454  		/* Check that the name-extension dirents are all allocated */
455  		for (tmp = 1; tmp < nr_slots; tmp++) {
456  			unsigned int ix = offset + tmp;
457  			if (!(block->hdr.bitmap[ix / 8] & (1 << (ix % 8)))) {
458  				_debug("ENT[%zu.u]:"
459  				       " %u unmarked extension (%u/%u)",
460  				       blkoff / sizeof(union afs_xdr_dir_block),
461  				       offset, tmp, nr_slots);
462  				return afs_bad(dvnode, afs_file_error_dir_unmarked_ext);
463  			}
464  		}
465  
466  		/* skip if starts before the current position */
467  		if (offset < curr) {
468  			if (next > curr)
469  				ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
470  			continue;
471  		}
472  
473  		/* found the next entry */
474  		if (!dir_emit(ctx, dire->u.name, nlen,
475  			      ntohl(dire->u.vnode),
476  			      (ctx->actor == afs_lookup_filldir ||
477  			       ctx->actor == afs_lookup_one_filldir)?
478  			      ntohl(dire->u.unique) : DT_UNKNOWN)) {
479  			_leave(" = 0 [full]");
480  			return 0;
481  		}
482  
483  		ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
484  	}
485  
486  	_leave(" = 1 [more]");
487  	return 1;
488  }
489  
490  /*
491   * iterate through the data blob that lists the contents of an AFS directory
492   */
493  static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
494  			   struct key *key, afs_dataversion_t *_dir_version)
495  {
496  	struct afs_vnode *dvnode = AFS_FS_I(dir);
497  	union afs_xdr_dir_block *dblock;
498  	struct afs_read *req;
499  	struct folio *folio;
500  	unsigned offset, size;
501  	int ret;
502  
503  	_enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
504  
505  	if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
506  		_leave(" = -ESTALE");
507  		return -ESTALE;
508  	}
509  
510  	req = afs_read_dir(dvnode, key);
511  	if (IS_ERR(req))
512  		return PTR_ERR(req);
513  	*_dir_version = req->data_version;
514  
515  	/* round the file position up to the next entry boundary */
516  	ctx->pos += sizeof(union afs_xdr_dirent) - 1;
517  	ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1);
518  
519  	/* walk through the blocks in sequence */
520  	ret = 0;
521  	while (ctx->pos < req->actual_len) {
522  		/* Fetch the appropriate folio from the directory and re-add it
523  		 * to the LRU.  We have all the pages pinned with an extra ref.
524  		 */
525  		folio = __filemap_get_folio(dir->i_mapping, ctx->pos / PAGE_SIZE,
526  					    FGP_ACCESSED, 0);
527  		if (!folio) {
528  			ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
529  			break;
530  		}
531  
532  		offset = round_down(ctx->pos, sizeof(*dblock)) - folio_file_pos(folio);
533  		size = min_t(loff_t, folio_size(folio),
534  			     req->actual_len - folio_file_pos(folio));
535  
536  		do {
537  			dblock = kmap_local_folio(folio, offset);
538  			ret = afs_dir_iterate_block(dvnode, ctx, dblock,
539  						    folio_file_pos(folio) + offset);
540  			kunmap_local(dblock);
541  			if (ret != 1)
542  				goto out;
543  
544  		} while (offset += sizeof(*dblock), offset < size);
545  
546  		ret = 0;
547  	}
548  
549  out:
550  	up_read(&dvnode->validate_lock);
551  	afs_put_read(req);
552  	_leave(" = %d", ret);
553  	return ret;
554  }
555  
556  /*
557   * read an AFS directory
558   */
559  static int afs_readdir(struct file *file, struct dir_context *ctx)
560  {
561  	afs_dataversion_t dir_version;
562  
563  	return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file),
564  			       &dir_version);
565  }
566  
567  /*
568   * Search the directory for a single name
569   * - if afs_dir_iterate_block() spots this function, it'll pass the FID
570   *   uniquifier through dtype
571   */
572  static bool afs_lookup_one_filldir(struct dir_context *ctx, const char *name,
573  				  int nlen, loff_t fpos, u64 ino, unsigned dtype)
574  {
575  	struct afs_lookup_one_cookie *cookie =
576  		container_of(ctx, struct afs_lookup_one_cookie, ctx);
577  
578  	_enter("{%s,%u},%s,%u,,%llu,%u",
579  	       cookie->name.name, cookie->name.len, name, nlen,
580  	       (unsigned long long) ino, dtype);
581  
582  	/* insanity checks first */
583  	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
584  	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
585  
586  	if (cookie->name.len != nlen ||
587  	    memcmp(cookie->name.name, name, nlen) != 0) {
588  		_leave(" = true [keep looking]");
589  		return true;
590  	}
591  
592  	cookie->fid.vnode = ino;
593  	cookie->fid.unique = dtype;
594  	cookie->found = 1;
595  
596  	_leave(" = false [found]");
597  	return false;
598  }
599  
600  /*
601   * Do a lookup of a single name in a directory
602   * - just returns the FID the dentry name maps to if found
603   */
604  static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
605  			     struct afs_fid *fid, struct key *key,
606  			     afs_dataversion_t *_dir_version)
607  {
608  	struct afs_super_info *as = dir->i_sb->s_fs_info;
609  	struct afs_lookup_one_cookie cookie = {
610  		.ctx.actor = afs_lookup_one_filldir,
611  		.name = dentry->d_name,
612  		.fid.vid = as->volume->vid
613  	};
614  	int ret;
615  
616  	_enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
617  
618  	/* search the directory */
619  	ret = afs_dir_iterate(dir, &cookie.ctx, key, _dir_version);
620  	if (ret < 0) {
621  		_leave(" = %d [iter]", ret);
622  		return ret;
623  	}
624  
625  	if (!cookie.found) {
626  		_leave(" = -ENOENT [not found]");
627  		return -ENOENT;
628  	}
629  
630  	*fid = cookie.fid;
631  	_leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique);
632  	return 0;
633  }
634  
635  /*
636   * search the directory for a name
637   * - if afs_dir_iterate_block() spots this function, it'll pass the FID
638   *   uniquifier through dtype
639   */
640  static bool afs_lookup_filldir(struct dir_context *ctx, const char *name,
641  			      int nlen, loff_t fpos, u64 ino, unsigned dtype)
642  {
643  	struct afs_lookup_cookie *cookie =
644  		container_of(ctx, struct afs_lookup_cookie, ctx);
645  
646  	_enter("{%s,%u},%s,%u,,%llu,%u",
647  	       cookie->name.name, cookie->name.len, name, nlen,
648  	       (unsigned long long) ino, dtype);
649  
650  	/* insanity checks first */
651  	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
652  	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
653  
654  	if (cookie->found) {
655  		if (cookie->nr_fids < 50) {
656  			cookie->fids[cookie->nr_fids].vnode	= ino;
657  			cookie->fids[cookie->nr_fids].unique	= dtype;
658  			cookie->nr_fids++;
659  		}
660  	} else if (cookie->name.len == nlen &&
661  		   memcmp(cookie->name.name, name, nlen) == 0) {
662  		cookie->fids[1].vnode	= ino;
663  		cookie->fids[1].unique	= dtype;
664  		cookie->found = 1;
665  		if (cookie->one_only)
666  			return false;
667  	}
668  
669  	return cookie->nr_fids < 50;
670  }
671  
672  /*
673   * Deal with the result of a successful lookup operation.  Turn all the files
674   * into inodes and save the first one - which is the one we actually want.
675   */
676  static void afs_do_lookup_success(struct afs_operation *op)
677  {
678  	struct afs_vnode_param *vp;
679  	struct afs_vnode *vnode;
680  	struct inode *inode;
681  	u32 abort_code;
682  	int i;
683  
684  	_enter("");
685  
686  	for (i = 0; i < op->nr_files; i++) {
687  		switch (i) {
688  		case 0:
689  			vp = &op->file[0];
690  			abort_code = vp->scb.status.abort_code;
691  			if (abort_code != 0) {
692  				op->ac.abort_code = abort_code;
693  				op->error = afs_abort_to_error(abort_code);
694  			}
695  			break;
696  
697  		case 1:
698  			vp = &op->file[1];
699  			break;
700  
701  		default:
702  			vp = &op->more_files[i - 2];
703  			break;
704  		}
705  
706  		if (!vp->scb.have_status && !vp->scb.have_error)
707  			continue;
708  
709  		_debug("do [%u]", i);
710  		if (vp->vnode) {
711  			if (!test_bit(AFS_VNODE_UNSET, &vp->vnode->flags))
712  				afs_vnode_commit_status(op, vp);
713  		} else if (vp->scb.status.abort_code == 0) {
714  			inode = afs_iget(op, vp);
715  			if (!IS_ERR(inode)) {
716  				vnode = AFS_FS_I(inode);
717  				afs_cache_permit(vnode, op->key,
718  						 0 /* Assume vnode->cb_break is 0 */ +
719  						 op->cb_v_break,
720  						 &vp->scb);
721  				vp->vnode = vnode;
722  				vp->put_vnode = true;
723  			}
724  		} else {
725  			_debug("- abort %d %llx:%llx.%x",
726  			       vp->scb.status.abort_code,
727  			       vp->fid.vid, vp->fid.vnode, vp->fid.unique);
728  		}
729  	}
730  
731  	_leave("");
732  }
733  
734  static const struct afs_operation_ops afs_inline_bulk_status_operation = {
735  	.issue_afs_rpc	= afs_fs_inline_bulk_status,
736  	.issue_yfs_rpc	= yfs_fs_inline_bulk_status,
737  	.success	= afs_do_lookup_success,
738  };
739  
740  static const struct afs_operation_ops afs_lookup_fetch_status_operation = {
741  	.issue_afs_rpc	= afs_fs_fetch_status,
742  	.issue_yfs_rpc	= yfs_fs_fetch_status,
743  	.success	= afs_do_lookup_success,
744  	.aborted	= afs_check_for_remote_deletion,
745  };
746  
747  /*
748   * See if we know that the server we expect to use doesn't support
749   * FS.InlineBulkStatus.
750   */
751  static bool afs_server_supports_ibulk(struct afs_vnode *dvnode)
752  {
753  	struct afs_server_list *slist;
754  	struct afs_volume *volume = dvnode->volume;
755  	struct afs_server *server;
756  	bool ret = true;
757  	int i;
758  
759  	if (!test_bit(AFS_VOLUME_MAYBE_NO_IBULK, &volume->flags))
760  		return true;
761  
762  	rcu_read_lock();
763  	slist = rcu_dereference(volume->servers);
764  
765  	for (i = 0; i < slist->nr_servers; i++) {
766  		server = slist->servers[i].server;
767  		if (server == dvnode->cb_server) {
768  			if (test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags))
769  				ret = false;
770  			break;
771  		}
772  	}
773  
774  	rcu_read_unlock();
775  	return ret;
776  }
777  
778  /*
779   * Do a lookup in a directory.  We make use of bulk lookup to query a slew of
780   * files in one go and create inodes for them.  The inode of the file we were
781   * asked for is returned.
782   */
783  static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
784  				   struct key *key)
785  {
786  	struct afs_lookup_cookie *cookie;
787  	struct afs_vnode_param *vp;
788  	struct afs_operation *op;
789  	struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
790  	struct inode *inode = NULL, *ti;
791  	afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version);
792  	long ret;
793  	int i;
794  
795  	_enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
796  
797  	cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL);
798  	if (!cookie)
799  		return ERR_PTR(-ENOMEM);
800  
801  	for (i = 0; i < ARRAY_SIZE(cookie->fids); i++)
802  		cookie->fids[i].vid = dvnode->fid.vid;
803  	cookie->ctx.actor = afs_lookup_filldir;
804  	cookie->name = dentry->d_name;
805  	cookie->nr_fids = 2; /* slot 0 is saved for the fid we actually want
806  			      * and slot 1 for the directory */
807  
808  	if (!afs_server_supports_ibulk(dvnode))
809  		cookie->one_only = true;
810  
811  	/* search the directory */
812  	ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version);
813  	if (ret < 0)
814  		goto out;
815  
816  	dentry->d_fsdata = (void *)(unsigned long)data_version;
817  
818  	ret = -ENOENT;
819  	if (!cookie->found)
820  		goto out;
821  
822  	/* Check to see if we already have an inode for the primary fid. */
823  	inode = ilookup5(dir->i_sb, cookie->fids[1].vnode,
824  			 afs_ilookup5_test_by_fid, &cookie->fids[1]);
825  	if (inode)
826  		goto out; /* We do */
827  
828  	/* Okay, we didn't find it.  We need to query the server - and whilst
829  	 * we're doing that, we're going to attempt to look up a bunch of other
830  	 * vnodes also.
831  	 */
832  	op = afs_alloc_operation(NULL, dvnode->volume);
833  	if (IS_ERR(op)) {
834  		ret = PTR_ERR(op);
835  		goto out;
836  	}
837  
838  	afs_op_set_vnode(op, 0, dvnode);
839  	afs_op_set_fid(op, 1, &cookie->fids[1]);
840  
841  	op->nr_files = cookie->nr_fids;
842  	_debug("nr_files %u", op->nr_files);
843  
844  	/* Need space for examining all the selected files */
845  	op->error = -ENOMEM;
846  	if (op->nr_files > 2) {
847  		op->more_files = kvcalloc(op->nr_files - 2,
848  					  sizeof(struct afs_vnode_param),
849  					  GFP_KERNEL);
850  		if (!op->more_files)
851  			goto out_op;
852  
853  		for (i = 2; i < op->nr_files; i++) {
854  			vp = &op->more_files[i - 2];
855  			vp->fid = cookie->fids[i];
856  
857  			/* Find any inodes that already exist and get their
858  			 * callback counters.
859  			 */
860  			ti = ilookup5_nowait(dir->i_sb, vp->fid.vnode,
861  					     afs_ilookup5_test_by_fid, &vp->fid);
862  			if (!IS_ERR_OR_NULL(ti)) {
863  				vnode = AFS_FS_I(ti);
864  				vp->dv_before = vnode->status.data_version;
865  				vp->cb_break_before = afs_calc_vnode_cb_break(vnode);
866  				vp->vnode = vnode;
867  				vp->put_vnode = true;
868  				vp->speculative = true; /* vnode not locked */
869  			}
870  		}
871  	}
872  
873  	/* Try FS.InlineBulkStatus first.  Abort codes for the individual
874  	 * lookups contained therein are stored in the reply without aborting
875  	 * the whole operation.
876  	 */
877  	op->error = -ENOTSUPP;
878  	if (!cookie->one_only) {
879  		op->ops = &afs_inline_bulk_status_operation;
880  		afs_begin_vnode_operation(op);
881  		afs_wait_for_operation(op);
882  	}
883  
884  	if (op->error == -ENOTSUPP) {
885  		/* We could try FS.BulkStatus next, but this aborts the entire
886  		 * op if any of the lookups fails - so, for the moment, revert
887  		 * to FS.FetchStatus for op->file[1].
888  		 */
889  		op->fetch_status.which = 1;
890  		op->ops = &afs_lookup_fetch_status_operation;
891  		afs_begin_vnode_operation(op);
892  		afs_wait_for_operation(op);
893  	}
894  	inode = ERR_PTR(op->error);
895  
896  out_op:
897  	if (op->error == 0) {
898  		inode = &op->file[1].vnode->netfs.inode;
899  		op->file[1].vnode = NULL;
900  	}
901  
902  	if (op->file[0].scb.have_status)
903  		dentry->d_fsdata = (void *)(unsigned long)op->file[0].scb.status.data_version;
904  	else
905  		dentry->d_fsdata = (void *)(unsigned long)op->file[0].dv_before;
906  	ret = afs_put_operation(op);
907  out:
908  	kfree(cookie);
909  	_leave("");
910  	return inode ?: ERR_PTR(ret);
911  }
912  
913  /*
914   * Look up an entry in a directory with @sys substitution.
915   */
916  static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry,
917  				       struct key *key)
918  {
919  	struct afs_sysnames *subs;
920  	struct afs_net *net = afs_i2net(dir);
921  	struct dentry *ret;
922  	char *buf, *p, *name;
923  	int len, i;
924  
925  	_enter("");
926  
927  	ret = ERR_PTR(-ENOMEM);
928  	p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL);
929  	if (!buf)
930  		goto out_p;
931  	if (dentry->d_name.len > 4) {
932  		memcpy(p, dentry->d_name.name, dentry->d_name.len - 4);
933  		p += dentry->d_name.len - 4;
934  	}
935  
936  	/* There is an ordered list of substitutes that we have to try. */
937  	read_lock(&net->sysnames_lock);
938  	subs = net->sysnames;
939  	refcount_inc(&subs->usage);
940  	read_unlock(&net->sysnames_lock);
941  
942  	for (i = 0; i < subs->nr; i++) {
943  		name = subs->subs[i];
944  		len = dentry->d_name.len - 4 + strlen(name);
945  		if (len >= AFSNAMEMAX) {
946  			ret = ERR_PTR(-ENAMETOOLONG);
947  			goto out_s;
948  		}
949  
950  		strcpy(p, name);
951  		ret = lookup_one_len(buf, dentry->d_parent, len);
952  		if (IS_ERR(ret) || d_is_positive(ret))
953  			goto out_s;
954  		dput(ret);
955  	}
956  
957  	/* We don't want to d_add() the @sys dentry here as we don't want to
958  	 * the cached dentry to hide changes to the sysnames list.
959  	 */
960  	ret = NULL;
961  out_s:
962  	afs_put_sysnames(subs);
963  	kfree(buf);
964  out_p:
965  	key_put(key);
966  	return ret;
967  }
968  
969  /*
970   * look up an entry in a directory
971   */
972  static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
973  				 unsigned int flags)
974  {
975  	struct afs_vnode *dvnode = AFS_FS_I(dir);
976  	struct afs_fid fid = {};
977  	struct inode *inode;
978  	struct dentry *d;
979  	struct key *key;
980  	int ret;
981  
982  	_enter("{%llx:%llu},%p{%pd},",
983  	       dvnode->fid.vid, dvnode->fid.vnode, dentry, dentry);
984  
985  	ASSERTCMP(d_inode(dentry), ==, NULL);
986  
987  	if (dentry->d_name.len >= AFSNAMEMAX) {
988  		_leave(" = -ENAMETOOLONG");
989  		return ERR_PTR(-ENAMETOOLONG);
990  	}
991  
992  	if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) {
993  		_leave(" = -ESTALE");
994  		return ERR_PTR(-ESTALE);
995  	}
996  
997  	key = afs_request_key(dvnode->volume->cell);
998  	if (IS_ERR(key)) {
999  		_leave(" = %ld [key]", PTR_ERR(key));
1000  		return ERR_CAST(key);
1001  	}
1002  
1003  	ret = afs_validate(dvnode, key);
1004  	if (ret < 0) {
1005  		key_put(key);
1006  		_leave(" = %d [val]", ret);
1007  		return ERR_PTR(ret);
1008  	}
1009  
1010  	if (dentry->d_name.len >= 4 &&
1011  	    dentry->d_name.name[dentry->d_name.len - 4] == '@' &&
1012  	    dentry->d_name.name[dentry->d_name.len - 3] == 's' &&
1013  	    dentry->d_name.name[dentry->d_name.len - 2] == 'y' &&
1014  	    dentry->d_name.name[dentry->d_name.len - 1] == 's')
1015  		return afs_lookup_atsys(dir, dentry, key);
1016  
1017  	afs_stat_v(dvnode, n_lookup);
1018  	inode = afs_do_lookup(dir, dentry, key);
1019  	key_put(key);
1020  	if (inode == ERR_PTR(-ENOENT))
1021  		inode = afs_try_auto_mntpt(dentry, dir);
1022  
1023  	if (!IS_ERR_OR_NULL(inode))
1024  		fid = AFS_FS_I(inode)->fid;
1025  
1026  	_debug("splice %p", dentry->d_inode);
1027  	d = d_splice_alias(inode, dentry);
1028  	if (!IS_ERR_OR_NULL(d)) {
1029  		d->d_fsdata = dentry->d_fsdata;
1030  		trace_afs_lookup(dvnode, &d->d_name, &fid);
1031  	} else {
1032  		trace_afs_lookup(dvnode, &dentry->d_name, &fid);
1033  	}
1034  	_leave("");
1035  	return d;
1036  }
1037  
1038  /*
1039   * Check the validity of a dentry under RCU conditions.
1040   */
1041  static int afs_d_revalidate_rcu(struct dentry *dentry)
1042  {
1043  	struct afs_vnode *dvnode;
1044  	struct dentry *parent;
1045  	struct inode *dir;
1046  	long dir_version, de_version;
1047  
1048  	_enter("%p", dentry);
1049  
1050  	/* Check the parent directory is still valid first. */
1051  	parent = READ_ONCE(dentry->d_parent);
1052  	dir = d_inode_rcu(parent);
1053  	if (!dir)
1054  		return -ECHILD;
1055  	dvnode = AFS_FS_I(dir);
1056  	if (test_bit(AFS_VNODE_DELETED, &dvnode->flags))
1057  		return -ECHILD;
1058  
1059  	if (!afs_check_validity(dvnode))
1060  		return -ECHILD;
1061  
1062  	/* We only need to invalidate a dentry if the server's copy changed
1063  	 * behind our back.  If we made the change, it's no problem.  Note that
1064  	 * on a 32-bit system, we only have 32 bits in the dentry to store the
1065  	 * version.
1066  	 */
1067  	dir_version = (long)READ_ONCE(dvnode->status.data_version);
1068  	de_version = (long)READ_ONCE(dentry->d_fsdata);
1069  	if (de_version != dir_version) {
1070  		dir_version = (long)READ_ONCE(dvnode->invalid_before);
1071  		if (de_version - dir_version < 0)
1072  			return -ECHILD;
1073  	}
1074  
1075  	return 1; /* Still valid */
1076  }
1077  
1078  /*
1079   * check that a dentry lookup hit has found a valid entry
1080   * - NOTE! the hit can be a negative hit too, so we can't assume we have an
1081   *   inode
1082   */
1083  static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
1084  {
1085  	struct afs_vnode *vnode, *dir;
1086  	struct afs_fid fid;
1087  	struct dentry *parent;
1088  	struct inode *inode;
1089  	struct key *key;
1090  	afs_dataversion_t dir_version, invalid_before;
1091  	long de_version;
1092  	int ret;
1093  
1094  	if (flags & LOOKUP_RCU)
1095  		return afs_d_revalidate_rcu(dentry);
1096  
1097  	if (d_really_is_positive(dentry)) {
1098  		vnode = AFS_FS_I(d_inode(dentry));
1099  		_enter("{v={%llx:%llu} n=%pd fl=%lx},",
1100  		       vnode->fid.vid, vnode->fid.vnode, dentry,
1101  		       vnode->flags);
1102  	} else {
1103  		_enter("{neg n=%pd}", dentry);
1104  	}
1105  
1106  	key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
1107  	if (IS_ERR(key))
1108  		key = NULL;
1109  
1110  	/* Hold the parent dentry so we can peer at it */
1111  	parent = dget_parent(dentry);
1112  	dir = AFS_FS_I(d_inode(parent));
1113  
1114  	/* validate the parent directory */
1115  	afs_validate(dir, key);
1116  
1117  	if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
1118  		_debug("%pd: parent dir deleted", dentry);
1119  		goto not_found;
1120  	}
1121  
1122  	/* We only need to invalidate a dentry if the server's copy changed
1123  	 * behind our back.  If we made the change, it's no problem.  Note that
1124  	 * on a 32-bit system, we only have 32 bits in the dentry to store the
1125  	 * version.
1126  	 */
1127  	dir_version = dir->status.data_version;
1128  	de_version = (long)dentry->d_fsdata;
1129  	if (de_version == (long)dir_version)
1130  		goto out_valid_noupdate;
1131  
1132  	invalid_before = dir->invalid_before;
1133  	if (de_version - (long)invalid_before >= 0)
1134  		goto out_valid;
1135  
1136  	_debug("dir modified");
1137  	afs_stat_v(dir, n_reval);
1138  
1139  	/* search the directory for this vnode */
1140  	ret = afs_do_lookup_one(&dir->netfs.inode, dentry, &fid, key, &dir_version);
1141  	switch (ret) {
1142  	case 0:
1143  		/* the filename maps to something */
1144  		if (d_really_is_negative(dentry))
1145  			goto not_found;
1146  		inode = d_inode(dentry);
1147  		if (is_bad_inode(inode)) {
1148  			printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
1149  			       dentry);
1150  			goto not_found;
1151  		}
1152  
1153  		vnode = AFS_FS_I(inode);
1154  
1155  		/* if the vnode ID has changed, then the dirent points to a
1156  		 * different file */
1157  		if (fid.vnode != vnode->fid.vnode) {
1158  			_debug("%pd: dirent changed [%llu != %llu]",
1159  			       dentry, fid.vnode,
1160  			       vnode->fid.vnode);
1161  			goto not_found;
1162  		}
1163  
1164  		/* if the vnode ID uniqifier has changed, then the file has
1165  		 * been deleted and replaced, and the original vnode ID has
1166  		 * been reused */
1167  		if (fid.unique != vnode->fid.unique) {
1168  			_debug("%pd: file deleted (uq %u -> %u I:%u)",
1169  			       dentry, fid.unique,
1170  			       vnode->fid.unique,
1171  			       vnode->netfs.inode.i_generation);
1172  			goto not_found;
1173  		}
1174  		goto out_valid;
1175  
1176  	case -ENOENT:
1177  		/* the filename is unknown */
1178  		_debug("%pd: dirent not found", dentry);
1179  		if (d_really_is_positive(dentry))
1180  			goto not_found;
1181  		goto out_valid;
1182  
1183  	default:
1184  		_debug("failed to iterate dir %pd: %d",
1185  		       parent, ret);
1186  		goto not_found;
1187  	}
1188  
1189  out_valid:
1190  	dentry->d_fsdata = (void *)(unsigned long)dir_version;
1191  out_valid_noupdate:
1192  	dput(parent);
1193  	key_put(key);
1194  	_leave(" = 1 [valid]");
1195  	return 1;
1196  
1197  not_found:
1198  	_debug("dropping dentry %pd2", dentry);
1199  	dput(parent);
1200  	key_put(key);
1201  
1202  	_leave(" = 0 [bad]");
1203  	return 0;
1204  }
1205  
1206  /*
1207   * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
1208   * sleep)
1209   * - called from dput() when d_count is going to 0.
1210   * - return 1 to request dentry be unhashed, 0 otherwise
1211   */
1212  static int afs_d_delete(const struct dentry *dentry)
1213  {
1214  	_enter("%pd", dentry);
1215  
1216  	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1217  		goto zap;
1218  
1219  	if (d_really_is_positive(dentry) &&
1220  	    (test_bit(AFS_VNODE_DELETED,   &AFS_FS_I(d_inode(dentry))->flags) ||
1221  	     test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
1222  		goto zap;
1223  
1224  	_leave(" = 0 [keep]");
1225  	return 0;
1226  
1227  zap:
1228  	_leave(" = 1 [zap]");
1229  	return 1;
1230  }
1231  
1232  /*
1233   * Clean up sillyrename files on dentry removal.
1234   */
1235  static void afs_d_iput(struct dentry *dentry, struct inode *inode)
1236  {
1237  	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1238  		afs_silly_iput(dentry, inode);
1239  	iput(inode);
1240  }
1241  
1242  /*
1243   * handle dentry release
1244   */
1245  void afs_d_release(struct dentry *dentry)
1246  {
1247  	_enter("%pd", dentry);
1248  }
1249  
1250  void afs_check_for_remote_deletion(struct afs_operation *op)
1251  {
1252  	struct afs_vnode *vnode = op->file[0].vnode;
1253  
1254  	switch (op->ac.abort_code) {
1255  	case VNOVNODE:
1256  		set_bit(AFS_VNODE_DELETED, &vnode->flags);
1257  		afs_break_callback(vnode, afs_cb_break_for_deleted);
1258  	}
1259  }
1260  
1261  /*
1262   * Create a new inode for create/mkdir/symlink
1263   */
1264  static void afs_vnode_new_inode(struct afs_operation *op)
1265  {
1266  	struct afs_vnode_param *vp = &op->file[1];
1267  	struct afs_vnode *vnode;
1268  	struct inode *inode;
1269  
1270  	_enter("");
1271  
1272  	ASSERTCMP(op->error, ==, 0);
1273  
1274  	inode = afs_iget(op, vp);
1275  	if (IS_ERR(inode)) {
1276  		/* ENOMEM or EINTR at a really inconvenient time - just abandon
1277  		 * the new directory on the server.
1278  		 */
1279  		op->error = PTR_ERR(inode);
1280  		return;
1281  	}
1282  
1283  	vnode = AFS_FS_I(inode);
1284  	set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
1285  	if (!op->error)
1286  		afs_cache_permit(vnode, op->key, vnode->cb_break, &vp->scb);
1287  	d_instantiate(op->dentry, inode);
1288  }
1289  
1290  static void afs_create_success(struct afs_operation *op)
1291  {
1292  	_enter("op=%08x", op->debug_id);
1293  	op->ctime = op->file[0].scb.status.mtime_client;
1294  	afs_vnode_commit_status(op, &op->file[0]);
1295  	afs_update_dentry_version(op, &op->file[0], op->dentry);
1296  	afs_vnode_new_inode(op);
1297  }
1298  
1299  static void afs_create_edit_dir(struct afs_operation *op)
1300  {
1301  	struct afs_vnode_param *dvp = &op->file[0];
1302  	struct afs_vnode_param *vp = &op->file[1];
1303  	struct afs_vnode *dvnode = dvp->vnode;
1304  
1305  	_enter("op=%08x", op->debug_id);
1306  
1307  	down_write(&dvnode->validate_lock);
1308  	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1309  	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1310  		afs_edit_dir_add(dvnode, &op->dentry->d_name, &vp->fid,
1311  				 op->create.reason);
1312  	up_write(&dvnode->validate_lock);
1313  }
1314  
1315  static void afs_create_put(struct afs_operation *op)
1316  {
1317  	_enter("op=%08x", op->debug_id);
1318  
1319  	if (op->error)
1320  		d_drop(op->dentry);
1321  }
1322  
1323  static const struct afs_operation_ops afs_mkdir_operation = {
1324  	.issue_afs_rpc	= afs_fs_make_dir,
1325  	.issue_yfs_rpc	= yfs_fs_make_dir,
1326  	.success	= afs_create_success,
1327  	.aborted	= afs_check_for_remote_deletion,
1328  	.edit_dir	= afs_create_edit_dir,
1329  	.put		= afs_create_put,
1330  };
1331  
1332  /*
1333   * create a directory on an AFS filesystem
1334   */
1335  static int afs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1336  		     struct dentry *dentry, umode_t mode)
1337  {
1338  	struct afs_operation *op;
1339  	struct afs_vnode *dvnode = AFS_FS_I(dir);
1340  
1341  	_enter("{%llx:%llu},{%pd},%ho",
1342  	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1343  
1344  	op = afs_alloc_operation(NULL, dvnode->volume);
1345  	if (IS_ERR(op)) {
1346  		d_drop(dentry);
1347  		return PTR_ERR(op);
1348  	}
1349  
1350  	afs_op_set_vnode(op, 0, dvnode);
1351  	op->file[0].dv_delta = 1;
1352  	op->file[0].modification = true;
1353  	op->file[0].update_ctime = true;
1354  	op->dentry	= dentry;
1355  	op->create.mode	= S_IFDIR | mode;
1356  	op->create.reason = afs_edit_dir_for_mkdir;
1357  	op->ops		= &afs_mkdir_operation;
1358  	return afs_do_sync_operation(op);
1359  }
1360  
1361  /*
1362   * Remove a subdir from a directory.
1363   */
1364  static void afs_dir_remove_subdir(struct dentry *dentry)
1365  {
1366  	if (d_really_is_positive(dentry)) {
1367  		struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1368  
1369  		clear_nlink(&vnode->netfs.inode);
1370  		set_bit(AFS_VNODE_DELETED, &vnode->flags);
1371  		clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
1372  		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
1373  	}
1374  }
1375  
1376  static void afs_rmdir_success(struct afs_operation *op)
1377  {
1378  	_enter("op=%08x", op->debug_id);
1379  	op->ctime = op->file[0].scb.status.mtime_client;
1380  	afs_vnode_commit_status(op, &op->file[0]);
1381  	afs_update_dentry_version(op, &op->file[0], op->dentry);
1382  }
1383  
1384  static void afs_rmdir_edit_dir(struct afs_operation *op)
1385  {
1386  	struct afs_vnode_param *dvp = &op->file[0];
1387  	struct afs_vnode *dvnode = dvp->vnode;
1388  
1389  	_enter("op=%08x", op->debug_id);
1390  	afs_dir_remove_subdir(op->dentry);
1391  
1392  	down_write(&dvnode->validate_lock);
1393  	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1394  	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1395  		afs_edit_dir_remove(dvnode, &op->dentry->d_name,
1396  				    afs_edit_dir_for_rmdir);
1397  	up_write(&dvnode->validate_lock);
1398  }
1399  
1400  static void afs_rmdir_put(struct afs_operation *op)
1401  {
1402  	_enter("op=%08x", op->debug_id);
1403  	if (op->file[1].vnode)
1404  		up_write(&op->file[1].vnode->rmdir_lock);
1405  }
1406  
1407  static const struct afs_operation_ops afs_rmdir_operation = {
1408  	.issue_afs_rpc	= afs_fs_remove_dir,
1409  	.issue_yfs_rpc	= yfs_fs_remove_dir,
1410  	.success	= afs_rmdir_success,
1411  	.aborted	= afs_check_for_remote_deletion,
1412  	.edit_dir	= afs_rmdir_edit_dir,
1413  	.put		= afs_rmdir_put,
1414  };
1415  
1416  /*
1417   * remove a directory from an AFS filesystem
1418   */
1419  static int afs_rmdir(struct inode *dir, struct dentry *dentry)
1420  {
1421  	struct afs_operation *op;
1422  	struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL;
1423  	int ret;
1424  
1425  	_enter("{%llx:%llu},{%pd}",
1426  	       dvnode->fid.vid, dvnode->fid.vnode, dentry);
1427  
1428  	op = afs_alloc_operation(NULL, dvnode->volume);
1429  	if (IS_ERR(op))
1430  		return PTR_ERR(op);
1431  
1432  	afs_op_set_vnode(op, 0, dvnode);
1433  	op->file[0].dv_delta = 1;
1434  	op->file[0].modification = true;
1435  	op->file[0].update_ctime = true;
1436  
1437  	op->dentry	= dentry;
1438  	op->ops		= &afs_rmdir_operation;
1439  
1440  	/* Try to make sure we have a callback promise on the victim. */
1441  	if (d_really_is_positive(dentry)) {
1442  		vnode = AFS_FS_I(d_inode(dentry));
1443  		ret = afs_validate(vnode, op->key);
1444  		if (ret < 0)
1445  			goto error;
1446  	}
1447  
1448  	if (vnode) {
1449  		ret = down_write_killable(&vnode->rmdir_lock);
1450  		if (ret < 0)
1451  			goto error;
1452  		op->file[1].vnode = vnode;
1453  	}
1454  
1455  	return afs_do_sync_operation(op);
1456  
1457  error:
1458  	return afs_put_operation(op);
1459  }
1460  
1461  /*
1462   * Remove a link to a file or symlink from a directory.
1463   *
1464   * If the file was not deleted due to excess hard links, the fileserver will
1465   * break the callback promise on the file - if it had one - before it returns
1466   * to us, and if it was deleted, it won't
1467   *
1468   * However, if we didn't have a callback promise outstanding, or it was
1469   * outstanding on a different server, then it won't break it either...
1470   */
1471  static void afs_dir_remove_link(struct afs_operation *op)
1472  {
1473  	struct afs_vnode *dvnode = op->file[0].vnode;
1474  	struct afs_vnode *vnode = op->file[1].vnode;
1475  	struct dentry *dentry = op->dentry;
1476  	int ret;
1477  
1478  	if (op->error != 0 ||
1479  	    (op->file[1].scb.have_status && op->file[1].scb.have_error))
1480  		return;
1481  	if (d_really_is_positive(dentry))
1482  		return;
1483  
1484  	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
1485  		/* Already done */
1486  	} else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
1487  		write_seqlock(&vnode->cb_lock);
1488  		drop_nlink(&vnode->netfs.inode);
1489  		if (vnode->netfs.inode.i_nlink == 0) {
1490  			set_bit(AFS_VNODE_DELETED, &vnode->flags);
1491  			__afs_break_callback(vnode, afs_cb_break_for_unlink);
1492  		}
1493  		write_sequnlock(&vnode->cb_lock);
1494  	} else {
1495  		afs_break_callback(vnode, afs_cb_break_for_unlink);
1496  
1497  		if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1498  			_debug("AFS_VNODE_DELETED");
1499  
1500  		ret = afs_validate(vnode, op->key);
1501  		if (ret != -ESTALE)
1502  			op->error = ret;
1503  	}
1504  
1505  	_debug("nlink %d [val %d]", vnode->netfs.inode.i_nlink, op->error);
1506  }
1507  
1508  static void afs_unlink_success(struct afs_operation *op)
1509  {
1510  	_enter("op=%08x", op->debug_id);
1511  	op->ctime = op->file[0].scb.status.mtime_client;
1512  	afs_check_dir_conflict(op, &op->file[0]);
1513  	afs_vnode_commit_status(op, &op->file[0]);
1514  	afs_vnode_commit_status(op, &op->file[1]);
1515  	afs_update_dentry_version(op, &op->file[0], op->dentry);
1516  	afs_dir_remove_link(op);
1517  }
1518  
1519  static void afs_unlink_edit_dir(struct afs_operation *op)
1520  {
1521  	struct afs_vnode_param *dvp = &op->file[0];
1522  	struct afs_vnode *dvnode = dvp->vnode;
1523  
1524  	_enter("op=%08x", op->debug_id);
1525  	down_write(&dvnode->validate_lock);
1526  	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1527  	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1528  		afs_edit_dir_remove(dvnode, &op->dentry->d_name,
1529  				    afs_edit_dir_for_unlink);
1530  	up_write(&dvnode->validate_lock);
1531  }
1532  
1533  static void afs_unlink_put(struct afs_operation *op)
1534  {
1535  	_enter("op=%08x", op->debug_id);
1536  	if (op->unlink.need_rehash && op->error < 0 && op->error != -ENOENT)
1537  		d_rehash(op->dentry);
1538  }
1539  
1540  static const struct afs_operation_ops afs_unlink_operation = {
1541  	.issue_afs_rpc	= afs_fs_remove_file,
1542  	.issue_yfs_rpc	= yfs_fs_remove_file,
1543  	.success	= afs_unlink_success,
1544  	.aborted	= afs_check_for_remote_deletion,
1545  	.edit_dir	= afs_unlink_edit_dir,
1546  	.put		= afs_unlink_put,
1547  };
1548  
1549  /*
1550   * Remove a file or symlink from an AFS filesystem.
1551   */
1552  static int afs_unlink(struct inode *dir, struct dentry *dentry)
1553  {
1554  	struct afs_operation *op;
1555  	struct afs_vnode *dvnode = AFS_FS_I(dir);
1556  	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1557  	int ret;
1558  
1559  	_enter("{%llx:%llu},{%pd}",
1560  	       dvnode->fid.vid, dvnode->fid.vnode, dentry);
1561  
1562  	if (dentry->d_name.len >= AFSNAMEMAX)
1563  		return -ENAMETOOLONG;
1564  
1565  	op = afs_alloc_operation(NULL, dvnode->volume);
1566  	if (IS_ERR(op))
1567  		return PTR_ERR(op);
1568  
1569  	afs_op_set_vnode(op, 0, dvnode);
1570  	op->file[0].dv_delta = 1;
1571  	op->file[0].modification = true;
1572  	op->file[0].update_ctime = true;
1573  
1574  	/* Try to make sure we have a callback promise on the victim. */
1575  	ret = afs_validate(vnode, op->key);
1576  	if (ret < 0) {
1577  		op->error = ret;
1578  		goto error;
1579  	}
1580  
1581  	spin_lock(&dentry->d_lock);
1582  	if (d_count(dentry) > 1) {
1583  		spin_unlock(&dentry->d_lock);
1584  		/* Start asynchronous writeout of the inode */
1585  		write_inode_now(d_inode(dentry), 0);
1586  		op->error = afs_sillyrename(dvnode, vnode, dentry, op->key);
1587  		goto error;
1588  	}
1589  	if (!d_unhashed(dentry)) {
1590  		/* Prevent a race with RCU lookup. */
1591  		__d_drop(dentry);
1592  		op->unlink.need_rehash = true;
1593  	}
1594  	spin_unlock(&dentry->d_lock);
1595  
1596  	op->file[1].vnode = vnode;
1597  	op->file[1].update_ctime = true;
1598  	op->file[1].op_unlinked = true;
1599  	op->dentry	= dentry;
1600  	op->ops		= &afs_unlink_operation;
1601  	afs_begin_vnode_operation(op);
1602  	afs_wait_for_operation(op);
1603  
1604  	/* If there was a conflict with a third party, check the status of the
1605  	 * unlinked vnode.
1606  	 */
1607  	if (op->error == 0 && (op->flags & AFS_OPERATION_DIR_CONFLICT)) {
1608  		op->file[1].update_ctime = false;
1609  		op->fetch_status.which = 1;
1610  		op->ops = &afs_fetch_status_operation;
1611  		afs_begin_vnode_operation(op);
1612  		afs_wait_for_operation(op);
1613  	}
1614  
1615  	return afs_put_operation(op);
1616  
1617  error:
1618  	return afs_put_operation(op);
1619  }
1620  
1621  static const struct afs_operation_ops afs_create_operation = {
1622  	.issue_afs_rpc	= afs_fs_create_file,
1623  	.issue_yfs_rpc	= yfs_fs_create_file,
1624  	.success	= afs_create_success,
1625  	.aborted	= afs_check_for_remote_deletion,
1626  	.edit_dir	= afs_create_edit_dir,
1627  	.put		= afs_create_put,
1628  };
1629  
1630  /*
1631   * create a regular file on an AFS filesystem
1632   */
1633  static int afs_create(struct mnt_idmap *idmap, struct inode *dir,
1634  		      struct dentry *dentry, umode_t mode, bool excl)
1635  {
1636  	struct afs_operation *op;
1637  	struct afs_vnode *dvnode = AFS_FS_I(dir);
1638  	int ret = -ENAMETOOLONG;
1639  
1640  	_enter("{%llx:%llu},{%pd},%ho",
1641  	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1642  
1643  	if (dentry->d_name.len >= AFSNAMEMAX)
1644  		goto error;
1645  
1646  	op = afs_alloc_operation(NULL, dvnode->volume);
1647  	if (IS_ERR(op)) {
1648  		ret = PTR_ERR(op);
1649  		goto error;
1650  	}
1651  
1652  	afs_op_set_vnode(op, 0, dvnode);
1653  	op->file[0].dv_delta = 1;
1654  	op->file[0].modification = true;
1655  	op->file[0].update_ctime = true;
1656  
1657  	op->dentry	= dentry;
1658  	op->create.mode	= S_IFREG | mode;
1659  	op->create.reason = afs_edit_dir_for_create;
1660  	op->ops		= &afs_create_operation;
1661  	return afs_do_sync_operation(op);
1662  
1663  error:
1664  	d_drop(dentry);
1665  	_leave(" = %d", ret);
1666  	return ret;
1667  }
1668  
1669  static void afs_link_success(struct afs_operation *op)
1670  {
1671  	struct afs_vnode_param *dvp = &op->file[0];
1672  	struct afs_vnode_param *vp = &op->file[1];
1673  
1674  	_enter("op=%08x", op->debug_id);
1675  	op->ctime = dvp->scb.status.mtime_client;
1676  	afs_vnode_commit_status(op, dvp);
1677  	afs_vnode_commit_status(op, vp);
1678  	afs_update_dentry_version(op, dvp, op->dentry);
1679  	if (op->dentry_2->d_parent == op->dentry->d_parent)
1680  		afs_update_dentry_version(op, dvp, op->dentry_2);
1681  	ihold(&vp->vnode->netfs.inode);
1682  	d_instantiate(op->dentry, &vp->vnode->netfs.inode);
1683  }
1684  
1685  static void afs_link_put(struct afs_operation *op)
1686  {
1687  	_enter("op=%08x", op->debug_id);
1688  	if (op->error)
1689  		d_drop(op->dentry);
1690  }
1691  
1692  static const struct afs_operation_ops afs_link_operation = {
1693  	.issue_afs_rpc	= afs_fs_link,
1694  	.issue_yfs_rpc	= yfs_fs_link,
1695  	.success	= afs_link_success,
1696  	.aborted	= afs_check_for_remote_deletion,
1697  	.edit_dir	= afs_create_edit_dir,
1698  	.put		= afs_link_put,
1699  };
1700  
1701  /*
1702   * create a hard link between files in an AFS filesystem
1703   */
1704  static int afs_link(struct dentry *from, struct inode *dir,
1705  		    struct dentry *dentry)
1706  {
1707  	struct afs_operation *op;
1708  	struct afs_vnode *dvnode = AFS_FS_I(dir);
1709  	struct afs_vnode *vnode = AFS_FS_I(d_inode(from));
1710  	int ret = -ENAMETOOLONG;
1711  
1712  	_enter("{%llx:%llu},{%llx:%llu},{%pd}",
1713  	       vnode->fid.vid, vnode->fid.vnode,
1714  	       dvnode->fid.vid, dvnode->fid.vnode,
1715  	       dentry);
1716  
1717  	if (dentry->d_name.len >= AFSNAMEMAX)
1718  		goto error;
1719  
1720  	op = afs_alloc_operation(NULL, dvnode->volume);
1721  	if (IS_ERR(op)) {
1722  		ret = PTR_ERR(op);
1723  		goto error;
1724  	}
1725  
1726  	ret = afs_validate(vnode, op->key);
1727  	if (ret < 0)
1728  		goto error_op;
1729  
1730  	afs_op_set_vnode(op, 0, dvnode);
1731  	afs_op_set_vnode(op, 1, vnode);
1732  	op->file[0].dv_delta = 1;
1733  	op->file[0].modification = true;
1734  	op->file[0].update_ctime = true;
1735  	op->file[1].update_ctime = true;
1736  
1737  	op->dentry		= dentry;
1738  	op->dentry_2		= from;
1739  	op->ops			= &afs_link_operation;
1740  	op->create.reason	= afs_edit_dir_for_link;
1741  	return afs_do_sync_operation(op);
1742  
1743  error_op:
1744  	afs_put_operation(op);
1745  error:
1746  	d_drop(dentry);
1747  	_leave(" = %d", ret);
1748  	return ret;
1749  }
1750  
1751  static const struct afs_operation_ops afs_symlink_operation = {
1752  	.issue_afs_rpc	= afs_fs_symlink,
1753  	.issue_yfs_rpc	= yfs_fs_symlink,
1754  	.success	= afs_create_success,
1755  	.aborted	= afs_check_for_remote_deletion,
1756  	.edit_dir	= afs_create_edit_dir,
1757  	.put		= afs_create_put,
1758  };
1759  
1760  /*
1761   * create a symlink in an AFS filesystem
1762   */
1763  static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
1764  		       struct dentry *dentry, const char *content)
1765  {
1766  	struct afs_operation *op;
1767  	struct afs_vnode *dvnode = AFS_FS_I(dir);
1768  	int ret;
1769  
1770  	_enter("{%llx:%llu},{%pd},%s",
1771  	       dvnode->fid.vid, dvnode->fid.vnode, dentry,
1772  	       content);
1773  
1774  	ret = -ENAMETOOLONG;
1775  	if (dentry->d_name.len >= AFSNAMEMAX)
1776  		goto error;
1777  
1778  	ret = -EINVAL;
1779  	if (strlen(content) >= AFSPATHMAX)
1780  		goto error;
1781  
1782  	op = afs_alloc_operation(NULL, dvnode->volume);
1783  	if (IS_ERR(op)) {
1784  		ret = PTR_ERR(op);
1785  		goto error;
1786  	}
1787  
1788  	afs_op_set_vnode(op, 0, dvnode);
1789  	op->file[0].dv_delta = 1;
1790  
1791  	op->dentry		= dentry;
1792  	op->ops			= &afs_symlink_operation;
1793  	op->create.reason	= afs_edit_dir_for_symlink;
1794  	op->create.symlink	= content;
1795  	return afs_do_sync_operation(op);
1796  
1797  error:
1798  	d_drop(dentry);
1799  	_leave(" = %d", ret);
1800  	return ret;
1801  }
1802  
1803  static void afs_rename_success(struct afs_operation *op)
1804  {
1805  	_enter("op=%08x", op->debug_id);
1806  
1807  	op->ctime = op->file[0].scb.status.mtime_client;
1808  	afs_check_dir_conflict(op, &op->file[1]);
1809  	afs_vnode_commit_status(op, &op->file[0]);
1810  	if (op->file[1].vnode != op->file[0].vnode) {
1811  		op->ctime = op->file[1].scb.status.mtime_client;
1812  		afs_vnode_commit_status(op, &op->file[1]);
1813  	}
1814  }
1815  
1816  static void afs_rename_edit_dir(struct afs_operation *op)
1817  {
1818  	struct afs_vnode_param *orig_dvp = &op->file[0];
1819  	struct afs_vnode_param *new_dvp = &op->file[1];
1820  	struct afs_vnode *orig_dvnode = orig_dvp->vnode;
1821  	struct afs_vnode *new_dvnode = new_dvp->vnode;
1822  	struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
1823  	struct dentry *old_dentry = op->dentry;
1824  	struct dentry *new_dentry = op->dentry_2;
1825  	struct inode *new_inode;
1826  
1827  	_enter("op=%08x", op->debug_id);
1828  
1829  	if (op->rename.rehash) {
1830  		d_rehash(op->rename.rehash);
1831  		op->rename.rehash = NULL;
1832  	}
1833  
1834  	down_write(&orig_dvnode->validate_lock);
1835  	if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags) &&
1836  	    orig_dvnode->status.data_version == orig_dvp->dv_before + orig_dvp->dv_delta)
1837  		afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
1838  				    afs_edit_dir_for_rename_0);
1839  
1840  	if (new_dvnode != orig_dvnode) {
1841  		up_write(&orig_dvnode->validate_lock);
1842  		down_write(&new_dvnode->validate_lock);
1843  	}
1844  
1845  	if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags) &&
1846  	    new_dvnode->status.data_version == new_dvp->dv_before + new_dvp->dv_delta) {
1847  		if (!op->rename.new_negative)
1848  			afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
1849  					    afs_edit_dir_for_rename_1);
1850  
1851  		afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
1852  				 &vnode->fid, afs_edit_dir_for_rename_2);
1853  	}
1854  
1855  	new_inode = d_inode(new_dentry);
1856  	if (new_inode) {
1857  		spin_lock(&new_inode->i_lock);
1858  		if (S_ISDIR(new_inode->i_mode))
1859  			clear_nlink(new_inode);
1860  		else if (new_inode->i_nlink > 0)
1861  			drop_nlink(new_inode);
1862  		spin_unlock(&new_inode->i_lock);
1863  	}
1864  
1865  	/* Now we can update d_fsdata on the dentries to reflect their
1866  	 * new parent's data_version.
1867  	 *
1868  	 * Note that if we ever implement RENAME_EXCHANGE, we'll have
1869  	 * to update both dentries with opposing dir versions.
1870  	 */
1871  	afs_update_dentry_version(op, new_dvp, op->dentry);
1872  	afs_update_dentry_version(op, new_dvp, op->dentry_2);
1873  
1874  	d_move(old_dentry, new_dentry);
1875  
1876  	up_write(&new_dvnode->validate_lock);
1877  }
1878  
1879  static void afs_rename_put(struct afs_operation *op)
1880  {
1881  	_enter("op=%08x", op->debug_id);
1882  	if (op->rename.rehash)
1883  		d_rehash(op->rename.rehash);
1884  	dput(op->rename.tmp);
1885  	if (op->error)
1886  		d_rehash(op->dentry);
1887  }
1888  
1889  static const struct afs_operation_ops afs_rename_operation = {
1890  	.issue_afs_rpc	= afs_fs_rename,
1891  	.issue_yfs_rpc	= yfs_fs_rename,
1892  	.success	= afs_rename_success,
1893  	.edit_dir	= afs_rename_edit_dir,
1894  	.put		= afs_rename_put,
1895  };
1896  
1897  /*
1898   * rename a file in an AFS filesystem and/or move it between directories
1899   */
1900  static int afs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
1901  		      struct dentry *old_dentry, struct inode *new_dir,
1902  		      struct dentry *new_dentry, unsigned int flags)
1903  {
1904  	struct afs_operation *op;
1905  	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
1906  	int ret;
1907  
1908  	if (flags)
1909  		return -EINVAL;
1910  
1911  	/* Don't allow silly-rename files be moved around. */
1912  	if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED)
1913  		return -EINVAL;
1914  
1915  	vnode = AFS_FS_I(d_inode(old_dentry));
1916  	orig_dvnode = AFS_FS_I(old_dir);
1917  	new_dvnode = AFS_FS_I(new_dir);
1918  
1919  	_enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%pd}",
1920  	       orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
1921  	       vnode->fid.vid, vnode->fid.vnode,
1922  	       new_dvnode->fid.vid, new_dvnode->fid.vnode,
1923  	       new_dentry);
1924  
1925  	op = afs_alloc_operation(NULL, orig_dvnode->volume);
1926  	if (IS_ERR(op))
1927  		return PTR_ERR(op);
1928  
1929  	ret = afs_validate(vnode, op->key);
1930  	op->error = ret;
1931  	if (ret < 0)
1932  		goto error;
1933  
1934  	afs_op_set_vnode(op, 0, orig_dvnode);
1935  	afs_op_set_vnode(op, 1, new_dvnode); /* May be same as orig_dvnode */
1936  	op->file[0].dv_delta = 1;
1937  	op->file[1].dv_delta = 1;
1938  	op->file[0].modification = true;
1939  	op->file[1].modification = true;
1940  	op->file[0].update_ctime = true;
1941  	op->file[1].update_ctime = true;
1942  
1943  	op->dentry		= old_dentry;
1944  	op->dentry_2		= new_dentry;
1945  	op->rename.new_negative	= d_is_negative(new_dentry);
1946  	op->ops			= &afs_rename_operation;
1947  
1948  	/* For non-directories, check whether the target is busy and if so,
1949  	 * make a copy of the dentry and then do a silly-rename.  If the
1950  	 * silly-rename succeeds, the copied dentry is hashed and becomes the
1951  	 * new target.
1952  	 */
1953  	if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) {
1954  		/* To prevent any new references to the target during the
1955  		 * rename, we unhash the dentry in advance.
1956  		 */
1957  		if (!d_unhashed(new_dentry)) {
1958  			d_drop(new_dentry);
1959  			op->rename.rehash = new_dentry;
1960  		}
1961  
1962  		if (d_count(new_dentry) > 2) {
1963  			/* copy the target dentry's name */
1964  			op->rename.tmp = d_alloc(new_dentry->d_parent,
1965  						 &new_dentry->d_name);
1966  			if (!op->rename.tmp) {
1967  				op->error = -ENOMEM;
1968  				goto error;
1969  			}
1970  
1971  			ret = afs_sillyrename(new_dvnode,
1972  					      AFS_FS_I(d_inode(new_dentry)),
1973  					      new_dentry, op->key);
1974  			if (ret) {
1975  				op->error = ret;
1976  				goto error;
1977  			}
1978  
1979  			op->dentry_2 = op->rename.tmp;
1980  			op->rename.rehash = NULL;
1981  			op->rename.new_negative = true;
1982  		}
1983  	}
1984  
1985  	/* This bit is potentially nasty as there's a potential race with
1986  	 * afs_d_revalidate{,_rcu}().  We have to change d_fsdata on the dentry
1987  	 * to reflect it's new parent's new data_version after the op, but
1988  	 * d_revalidate may see old_dentry between the op having taken place
1989  	 * and the version being updated.
1990  	 *
1991  	 * So drop the old_dentry for now to make other threads go through
1992  	 * lookup instead - which we hold a lock against.
1993  	 */
1994  	d_drop(old_dentry);
1995  
1996  	return afs_do_sync_operation(op);
1997  
1998  error:
1999  	return afs_put_operation(op);
2000  }
2001  
2002  /*
2003   * Release a directory folio and clean up its private state if it's not busy
2004   * - return true if the folio can now be released, false if not
2005   */
2006  static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags)
2007  {
2008  	struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
2009  
2010  	_enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, folio_index(folio));
2011  
2012  	folio_detach_private(folio);
2013  
2014  	/* The directory will need reloading. */
2015  	if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2016  		afs_stat_v(dvnode, n_relpg);
2017  	return true;
2018  }
2019  
2020  /*
2021   * Invalidate part or all of a folio.
2022   */
2023  static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
2024  				   size_t length)
2025  {
2026  	struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
2027  
2028  	_enter("{%lu},%zu,%zu", folio->index, offset, length);
2029  
2030  	BUG_ON(!folio_test_locked(folio));
2031  
2032  	/* The directory will need reloading. */
2033  	if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2034  		afs_stat_v(dvnode, n_inval);
2035  
2036  	/* we clean up only if the entire folio is being invalidated */
2037  	if (offset == 0 && length == folio_size(folio))
2038  		folio_detach_private(folio);
2039  }
2040