Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
[linux-2.6-microblaze.git] / fs / afs / dir.c
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 int afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen,
28                                   loff_t fpos, u64 ino, unsigned dtype);
29 static int 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 inode *dir, struct dentry *dentry, umode_t mode,
32                       bool excl);
33 static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
34 static int afs_rmdir(struct inode *dir, struct dentry *dentry);
35 static int afs_unlink(struct inode *dir, struct dentry *dentry);
36 static int afs_link(struct dentry *from, struct inode *dir,
37                     struct dentry *dentry);
38 static int afs_symlink(struct inode *dir, struct dentry *dentry,
39                        const char *content);
40 static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
41                       struct inode *new_dir, struct dentry *new_dentry,
42                       unsigned int flags);
43 static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags);
44 static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
45                                    unsigned int length);
46
47 static int afs_dir_set_page_dirty(struct page *page)
48 {
49         BUG(); /* This should never happen. */
50 }
51
52 const struct file_operations afs_dir_file_operations = {
53         .open           = afs_dir_open,
54         .release        = afs_release,
55         .iterate_shared = afs_readdir,
56         .lock           = afs_lock,
57         .llseek         = generic_file_llseek,
58 };
59
60 const struct inode_operations afs_dir_inode_operations = {
61         .create         = afs_create,
62         .lookup         = afs_lookup,
63         .link           = afs_link,
64         .unlink         = afs_unlink,
65         .symlink        = afs_symlink,
66         .mkdir          = afs_mkdir,
67         .rmdir          = afs_rmdir,
68         .rename         = afs_rename,
69         .permission     = afs_permission,
70         .getattr        = afs_getattr,
71         .setattr        = afs_setattr,
72         .listxattr      = afs_listxattr,
73 };
74
75 const struct address_space_operations afs_dir_aops = {
76         .set_page_dirty = afs_dir_set_page_dirty,
77         .releasepage    = afs_dir_releasepage,
78         .invalidatepage = afs_dir_invalidatepage,
79 };
80
81 const struct dentry_operations afs_fs_dentry_operations = {
82         .d_revalidate   = afs_d_revalidate,
83         .d_delete       = afs_d_delete,
84         .d_release      = afs_d_release,
85         .d_automount    = afs_d_automount,
86         .d_iput         = afs_d_iput,
87 };
88
89 struct afs_lookup_one_cookie {
90         struct dir_context      ctx;
91         struct qstr             name;
92         bool                    found;
93         struct afs_fid          fid;
94 };
95
96 struct afs_lookup_cookie {
97         struct dir_context      ctx;
98         struct qstr             name;
99         bool                    found;
100         bool                    one_only;
101         unsigned short          nr_fids;
102         struct inode            **inodes;
103         struct afs_status_cb    *statuses;
104         struct afs_fid          fids[50];
105 };
106
107 /*
108  * check that a directory page is valid
109  */
110 static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page,
111                                loff_t i_size)
112 {
113         struct afs_xdr_dir_page *dbuf;
114         loff_t latter, off;
115         int tmp, qty;
116
117         /* Determine how many magic numbers there should be in this page, but
118          * we must take care because the directory may change size under us.
119          */
120         off = page_offset(page);
121         if (i_size <= off)
122                 goto checked;
123
124         latter = i_size - off;
125         if (latter >= PAGE_SIZE)
126                 qty = PAGE_SIZE;
127         else
128                 qty = latter;
129         qty /= sizeof(union afs_xdr_dir_block);
130
131         /* check them */
132         dbuf = kmap(page);
133         for (tmp = 0; tmp < qty; tmp++) {
134                 if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) {
135                         printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n",
136                                __func__, dvnode->vfs_inode.i_ino, tmp, qty,
137                                ntohs(dbuf->blocks[tmp].hdr.magic));
138                         trace_afs_dir_check_failed(dvnode, off, i_size);
139                         kunmap(page);
140                         trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
141                         goto error;
142                 }
143
144                 /* Make sure each block is NUL terminated so we can reasonably
145                  * use string functions on it.  The filenames in the page
146                  * *should* be NUL-terminated anyway.
147                  */
148                 ((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0;
149         }
150
151         kunmap(page);
152
153 checked:
154         afs_stat_v(dvnode, n_read_dir);
155         return true;
156
157 error:
158         return false;
159 }
160
161 /*
162  * Check the contents of a directory that we've just read.
163  */
164 static bool afs_dir_check_pages(struct afs_vnode *dvnode, struct afs_read *req)
165 {
166         struct afs_xdr_dir_page *dbuf;
167         unsigned int i, j, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block);
168
169         for (i = 0; i < req->nr_pages; i++)
170                 if (!afs_dir_check_page(dvnode, req->pages[i], req->actual_len))
171                         goto bad;
172         return true;
173
174 bad:
175         pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx r=%llx\n",
176                 dvnode->fid.vid, dvnode->fid.vnode,
177                 req->file_size, req->len, req->actual_len, req->remain);
178         pr_warn("DIR %llx %x %x %x\n",
179                 req->pos, req->index, req->nr_pages, req->offset);
180
181         for (i = 0; i < req->nr_pages; i++) {
182                 dbuf = kmap(req->pages[i]);
183                 for (j = 0; j < qty; j++) {
184                         union afs_xdr_dir_block *block = &dbuf->blocks[j];
185
186                         pr_warn("[%02x] %32phN\n", i * qty + j, block);
187                 }
188                 kunmap(req->pages[i]);
189         }
190         return false;
191 }
192
193 /*
194  * open an AFS directory file
195  */
196 static int afs_dir_open(struct inode *inode, struct file *file)
197 {
198         _enter("{%lu}", inode->i_ino);
199
200         BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
201         BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
202
203         if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
204                 return -ENOENT;
205
206         return afs_open(inode, file);
207 }
208
209 /*
210  * Read the directory into the pagecache in one go, scrubbing the previous
211  * contents.  The list of pages is returned, pinning them so that they don't
212  * get reclaimed during the iteration.
213  */
214 static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
215         __acquires(&dvnode->validate_lock)
216 {
217         struct afs_read *req;
218         loff_t i_size;
219         int nr_pages, nr_inline, i, n;
220         int ret = -ENOMEM;
221
222 retry:
223         i_size = i_size_read(&dvnode->vfs_inode);
224         if (i_size < 2048)
225                 return ERR_PTR(afs_bad(dvnode, afs_file_error_dir_small));
226         if (i_size > 2048 * 1024) {
227                 trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
228                 return ERR_PTR(-EFBIG);
229         }
230
231         _enter("%llu", i_size);
232
233         /* Get a request record to hold the page list.  We want to hold it
234          * inline if we can, but we don't want to make an order 1 allocation.
235          */
236         nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE;
237         nr_inline = nr_pages;
238         if (nr_inline > (PAGE_SIZE - sizeof(*req)) / sizeof(struct page *))
239                 nr_inline = 0;
240
241         req = kzalloc(struct_size(req, array, nr_inline), GFP_KERNEL);
242         if (!req)
243                 return ERR_PTR(-ENOMEM);
244
245         refcount_set(&req->usage, 1);
246         req->nr_pages = nr_pages;
247         req->actual_len = i_size; /* May change */
248         req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
249         req->data_version = dvnode->status.data_version; /* May change */
250         if (nr_inline > 0) {
251                 req->pages = req->array;
252         } else {
253                 req->pages = kcalloc(nr_pages, sizeof(struct page *),
254                                      GFP_KERNEL);
255                 if (!req->pages)
256                         goto error;
257         }
258
259         /* Get a list of all the pages that hold or will hold the directory
260          * content.  We need to fill in any gaps that we might find where the
261          * memory reclaimer has been at work.  If there are any gaps, we will
262          * need to reread the entire directory contents.
263          */
264         i = 0;
265         do {
266                 n = find_get_pages_contig(dvnode->vfs_inode.i_mapping, i,
267                                           req->nr_pages - i,
268                                           req->pages + i);
269                 _debug("find %u at %u/%u", n, i, req->nr_pages);
270                 if (n == 0) {
271                         gfp_t gfp = dvnode->vfs_inode.i_mapping->gfp_mask;
272
273                         if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
274                                 afs_stat_v(dvnode, n_inval);
275
276                         ret = -ENOMEM;
277                         req->pages[i] = __page_cache_alloc(gfp);
278                         if (!req->pages[i])
279                                 goto error;
280                         ret = add_to_page_cache_lru(req->pages[i],
281                                                     dvnode->vfs_inode.i_mapping,
282                                                     i, gfp);
283                         if (ret < 0)
284                                 goto error;
285
286                         set_page_private(req->pages[i], 1);
287                         SetPagePrivate(req->pages[i]);
288                         unlock_page(req->pages[i]);
289                         i++;
290                 } else {
291                         i += n;
292                 }
293         } while (i < req->nr_pages);
294
295         /* If we're going to reload, we need to lock all the pages to prevent
296          * races.
297          */
298         ret = -ERESTARTSYS;
299         if (down_read_killable(&dvnode->validate_lock) < 0)
300                 goto error;
301
302         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
303                 goto success;
304
305         up_read(&dvnode->validate_lock);
306         if (down_write_killable(&dvnode->validate_lock) < 0)
307                 goto error;
308
309         if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
310                 trace_afs_reload_dir(dvnode);
311                 ret = afs_fetch_data(dvnode, key, req);
312                 if (ret < 0)
313                         goto error_unlock;
314
315                 task_io_account_read(PAGE_SIZE * req->nr_pages);
316
317                 if (req->len < req->file_size)
318                         goto content_has_grown;
319
320                 /* Validate the data we just read. */
321                 ret = -EIO;
322                 if (!afs_dir_check_pages(dvnode, req))
323                         goto error_unlock;
324
325                 // TODO: Trim excess pages
326
327                 set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags);
328         }
329
330         downgrade_write(&dvnode->validate_lock);
331 success:
332         return req;
333
334 error_unlock:
335         up_write(&dvnode->validate_lock);
336 error:
337         afs_put_read(req);
338         _leave(" = %d", ret);
339         return ERR_PTR(ret);
340
341 content_has_grown:
342         up_write(&dvnode->validate_lock);
343         afs_put_read(req);
344         goto retry;
345 }
346
347 /*
348  * deal with one block in an AFS directory
349  */
350 static int afs_dir_iterate_block(struct afs_vnode *dvnode,
351                                  struct dir_context *ctx,
352                                  union afs_xdr_dir_block *block,
353                                  unsigned blkoff)
354 {
355         union afs_xdr_dirent *dire;
356         unsigned offset, next, curr;
357         size_t nlen;
358         int tmp;
359
360         _enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block);
361
362         curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
363
364         /* walk through the block, an entry at a time */
365         for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
366              offset < AFS_DIR_SLOTS_PER_BLOCK;
367              offset = next
368              ) {
369                 next = offset + 1;
370
371                 /* skip entries marked unused in the bitmap */
372                 if (!(block->hdr.bitmap[offset / 8] &
373                       (1 << (offset % 8)))) {
374                         _debug("ENT[%zu.%u]: unused",
375                                blkoff / sizeof(union afs_xdr_dir_block), offset);
376                         if (offset >= curr)
377                                 ctx->pos = blkoff +
378                                         next * sizeof(union afs_xdr_dirent);
379                         continue;
380                 }
381
382                 /* got a valid entry */
383                 dire = &block->dirents[offset];
384                 nlen = strnlen(dire->u.name,
385                                sizeof(*block) -
386                                offset * sizeof(union afs_xdr_dirent));
387
388                 _debug("ENT[%zu.%u]: %s %zu \"%s\"",
389                        blkoff / sizeof(union afs_xdr_dir_block), offset,
390                        (offset < curr ? "skip" : "fill"),
391                        nlen, dire->u.name);
392
393                 /* work out where the next possible entry is */
394                 for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_xdr_dirent)) {
395                         if (next >= AFS_DIR_SLOTS_PER_BLOCK) {
396                                 _debug("ENT[%zu.%u]:"
397                                        " %u travelled beyond end dir block"
398                                        " (len %u/%zu)",
399                                        blkoff / sizeof(union afs_xdr_dir_block),
400                                        offset, next, tmp, nlen);
401                                 return afs_bad(dvnode, afs_file_error_dir_over_end);
402                         }
403                         if (!(block->hdr.bitmap[next / 8] &
404                               (1 << (next % 8)))) {
405                                 _debug("ENT[%zu.%u]:"
406                                        " %u unmarked extension (len %u/%zu)",
407                                        blkoff / sizeof(union afs_xdr_dir_block),
408                                        offset, next, tmp, nlen);
409                                 return afs_bad(dvnode, afs_file_error_dir_unmarked_ext);
410                         }
411
412                         _debug("ENT[%zu.%u]: ext %u/%zu",
413                                blkoff / sizeof(union afs_xdr_dir_block),
414                                next, tmp, nlen);
415                         next++;
416                 }
417
418                 /* skip if starts before the current position */
419                 if (offset < curr)
420                         continue;
421
422                 /* found the next entry */
423                 if (!dir_emit(ctx, dire->u.name, nlen,
424                               ntohl(dire->u.vnode),
425                               (ctx->actor == afs_lookup_filldir ||
426                                ctx->actor == afs_lookup_one_filldir)?
427                               ntohl(dire->u.unique) : DT_UNKNOWN)) {
428                         _leave(" = 0 [full]");
429                         return 0;
430                 }
431
432                 ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
433         }
434
435         _leave(" = 1 [more]");
436         return 1;
437 }
438
439 /*
440  * iterate through the data blob that lists the contents of an AFS directory
441  */
442 static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
443                            struct key *key, afs_dataversion_t *_dir_version)
444 {
445         struct afs_vnode *dvnode = AFS_FS_I(dir);
446         struct afs_xdr_dir_page *dbuf;
447         union afs_xdr_dir_block *dblock;
448         struct afs_read *req;
449         struct page *page;
450         unsigned blkoff, limit;
451         int ret;
452
453         _enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
454
455         if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
456                 _leave(" = -ESTALE");
457                 return -ESTALE;
458         }
459
460         req = afs_read_dir(dvnode, key);
461         if (IS_ERR(req))
462                 return PTR_ERR(req);
463         *_dir_version = req->data_version;
464
465         /* round the file position up to the next entry boundary */
466         ctx->pos += sizeof(union afs_xdr_dirent) - 1;
467         ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1);
468
469         /* walk through the blocks in sequence */
470         ret = 0;
471         while (ctx->pos < req->actual_len) {
472                 blkoff = ctx->pos & ~(sizeof(union afs_xdr_dir_block) - 1);
473
474                 /* Fetch the appropriate page from the directory and re-add it
475                  * to the LRU.
476                  */
477                 page = req->pages[blkoff / PAGE_SIZE];
478                 if (!page) {
479                         ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
480                         break;
481                 }
482                 mark_page_accessed(page);
483
484                 limit = blkoff & ~(PAGE_SIZE - 1);
485
486                 dbuf = kmap(page);
487
488                 /* deal with the individual blocks stashed on this page */
489                 do {
490                         dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) /
491                                                sizeof(union afs_xdr_dir_block)];
492                         ret = afs_dir_iterate_block(dvnode, ctx, dblock, blkoff);
493                         if (ret != 1) {
494                                 kunmap(page);
495                                 goto out;
496                         }
497
498                         blkoff += sizeof(union afs_xdr_dir_block);
499
500                 } while (ctx->pos < dir->i_size && blkoff < limit);
501
502                 kunmap(page);
503                 ret = 0;
504         }
505
506 out:
507         up_read(&dvnode->validate_lock);
508         afs_put_read(req);
509         _leave(" = %d", ret);
510         return ret;
511 }
512
513 /*
514  * read an AFS directory
515  */
516 static int afs_readdir(struct file *file, struct dir_context *ctx)
517 {
518         afs_dataversion_t dir_version;
519
520         return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file),
521                                &dir_version);
522 }
523
524 /*
525  * Search the directory for a single name
526  * - if afs_dir_iterate_block() spots this function, it'll pass the FID
527  *   uniquifier through dtype
528  */
529 static int afs_lookup_one_filldir(struct dir_context *ctx, const char *name,
530                                   int nlen, loff_t fpos, u64 ino, unsigned dtype)
531 {
532         struct afs_lookup_one_cookie *cookie =
533                 container_of(ctx, struct afs_lookup_one_cookie, ctx);
534
535         _enter("{%s,%u},%s,%u,,%llu,%u",
536                cookie->name.name, cookie->name.len, name, nlen,
537                (unsigned long long) ino, dtype);
538
539         /* insanity checks first */
540         BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
541         BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
542
543         if (cookie->name.len != nlen ||
544             memcmp(cookie->name.name, name, nlen) != 0) {
545                 _leave(" = 0 [no]");
546                 return 0;
547         }
548
549         cookie->fid.vnode = ino;
550         cookie->fid.unique = dtype;
551         cookie->found = 1;
552
553         _leave(" = -1 [found]");
554         return -1;
555 }
556
557 /*
558  * Do a lookup of a single name in a directory
559  * - just returns the FID the dentry name maps to if found
560  */
561 static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
562                              struct afs_fid *fid, struct key *key,
563                              afs_dataversion_t *_dir_version)
564 {
565         struct afs_super_info *as = dir->i_sb->s_fs_info;
566         struct afs_lookup_one_cookie cookie = {
567                 .ctx.actor = afs_lookup_one_filldir,
568                 .name = dentry->d_name,
569                 .fid.vid = as->volume->vid
570         };
571         int ret;
572
573         _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
574
575         /* search the directory */
576         ret = afs_dir_iterate(dir, &cookie.ctx, key, _dir_version);
577         if (ret < 0) {
578                 _leave(" = %d [iter]", ret);
579                 return ret;
580         }
581
582         ret = -ENOENT;
583         if (!cookie.found) {
584                 _leave(" = -ENOENT [not found]");
585                 return -ENOENT;
586         }
587
588         *fid = cookie.fid;
589         _leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique);
590         return 0;
591 }
592
593 /*
594  * search the directory for a name
595  * - if afs_dir_iterate_block() spots this function, it'll pass the FID
596  *   uniquifier through dtype
597  */
598 static int afs_lookup_filldir(struct dir_context *ctx, const char *name,
599                               int nlen, loff_t fpos, u64 ino, unsigned dtype)
600 {
601         struct afs_lookup_cookie *cookie =
602                 container_of(ctx, struct afs_lookup_cookie, ctx);
603         int ret;
604
605         _enter("{%s,%u},%s,%u,,%llu,%u",
606                cookie->name.name, cookie->name.len, name, nlen,
607                (unsigned long long) ino, dtype);
608
609         /* insanity checks first */
610         BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
611         BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
612
613         if (cookie->found) {
614                 if (cookie->nr_fids < 50) {
615                         cookie->fids[cookie->nr_fids].vnode     = ino;
616                         cookie->fids[cookie->nr_fids].unique    = dtype;
617                         cookie->nr_fids++;
618                 }
619         } else if (cookie->name.len == nlen &&
620                    memcmp(cookie->name.name, name, nlen) == 0) {
621                 cookie->fids[0].vnode   = ino;
622                 cookie->fids[0].unique  = dtype;
623                 cookie->found = 1;
624                 if (cookie->one_only)
625                         return -1;
626         }
627
628         ret = cookie->nr_fids >= 50 ? -1 : 0;
629         _leave(" = %d", ret);
630         return ret;
631 }
632
633 /*
634  * Do a lookup in a directory.  We make use of bulk lookup to query a slew of
635  * files in one go and create inodes for them.  The inode of the file we were
636  * asked for is returned.
637  */
638 static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
639                                    struct key *key)
640 {
641         struct afs_lookup_cookie *cookie;
642         struct afs_cb_interest *dcbi, *cbi = NULL;
643         struct afs_super_info *as = dir->i_sb->s_fs_info;
644         struct afs_status_cb *scb;
645         struct afs_iget_data iget_data;
646         struct afs_fs_cursor fc;
647         struct afs_server *server;
648         struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
649         struct inode *inode = NULL, *ti;
650         afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version);
651         int ret, i;
652
653         _enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
654
655         cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL);
656         if (!cookie)
657                 return ERR_PTR(-ENOMEM);
658
659         cookie->ctx.actor = afs_lookup_filldir;
660         cookie->name = dentry->d_name;
661         cookie->nr_fids = 1; /* slot 0 is saved for the fid we actually want */
662
663         read_seqlock_excl(&dvnode->cb_lock);
664         dcbi = rcu_dereference_protected(dvnode->cb_interest,
665                                          lockdep_is_held(&dvnode->cb_lock.lock));
666         if (dcbi) {
667                 server = dcbi->server;
668                 if (server &&
669                     test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags))
670                         cookie->one_only = true;
671         }
672         read_sequnlock_excl(&dvnode->cb_lock);
673
674         for (i = 0; i < 50; i++)
675                 cookie->fids[i].vid = as->volume->vid;
676
677         /* search the directory */
678         ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version);
679         if (ret < 0) {
680                 inode = ERR_PTR(ret);
681                 goto out;
682         }
683
684         dentry->d_fsdata = (void *)(unsigned long)data_version;
685
686         inode = ERR_PTR(-ENOENT);
687         if (!cookie->found)
688                 goto out;
689
690         /* Check to see if we already have an inode for the primary fid. */
691         iget_data.fid = cookie->fids[0];
692         iget_data.volume = dvnode->volume;
693         iget_data.cb_v_break = dvnode->volume->cb_v_break;
694         iget_data.cb_s_break = 0;
695         inode = ilookup5(dir->i_sb, cookie->fids[0].vnode,
696                          afs_iget5_test, &iget_data);
697         if (inode)
698                 goto out;
699
700         /* Need space for examining all the selected files */
701         inode = ERR_PTR(-ENOMEM);
702         cookie->statuses = kvcalloc(cookie->nr_fids, sizeof(struct afs_status_cb),
703                                     GFP_KERNEL);
704         if (!cookie->statuses)
705                 goto out;
706
707         cookie->inodes = kcalloc(cookie->nr_fids, sizeof(struct inode *),
708                                  GFP_KERNEL);
709         if (!cookie->inodes)
710                 goto out_s;
711
712         for (i = 1; i < cookie->nr_fids; i++) {
713                 scb = &cookie->statuses[i];
714
715                 /* Find any inodes that already exist and get their
716                  * callback counters.
717                  */
718                 iget_data.fid = cookie->fids[i];
719                 ti = ilookup5_nowait(dir->i_sb, iget_data.fid.vnode,
720                                      afs_iget5_test, &iget_data);
721                 if (!IS_ERR_OR_NULL(ti)) {
722                         vnode = AFS_FS_I(ti);
723                         scb->cb_break = afs_calc_vnode_cb_break(vnode);
724                         cookie->inodes[i] = ti;
725                 }
726         }
727
728         /* Try FS.InlineBulkStatus first.  Abort codes for the individual
729          * lookups contained therein are stored in the reply without aborting
730          * the whole operation.
731          */
732         if (cookie->one_only)
733                 goto no_inline_bulk_status;
734
735         inode = ERR_PTR(-ERESTARTSYS);
736         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
737                 while (afs_select_fileserver(&fc)) {
738                         if (test_bit(AFS_SERVER_FL_NO_IBULK,
739                                       &fc.cbi->server->flags)) {
740                                 fc.ac.abort_code = RX_INVALID_OPERATION;
741                                 fc.ac.error = -ECONNABORTED;
742                                 break;
743                         }
744                         iget_data.cb_v_break = dvnode->volume->cb_v_break;
745                         iget_data.cb_s_break = fc.cbi->server->cb_s_break;
746                         afs_fs_inline_bulk_status(&fc,
747                                                   afs_v2net(dvnode),
748                                                   cookie->fids,
749                                                   cookie->statuses,
750                                                   cookie->nr_fids, NULL);
751                 }
752
753                 if (fc.ac.error == 0)
754                         cbi = afs_get_cb_interest(fc.cbi);
755                 if (fc.ac.abort_code == RX_INVALID_OPERATION)
756                         set_bit(AFS_SERVER_FL_NO_IBULK, &fc.cbi->server->flags);
757                 inode = ERR_PTR(afs_end_vnode_operation(&fc));
758         }
759
760         if (!IS_ERR(inode))
761                 goto success;
762         if (fc.ac.abort_code != RX_INVALID_OPERATION)
763                 goto out_c;
764
765 no_inline_bulk_status:
766         /* We could try FS.BulkStatus next, but this aborts the entire op if
767          * any of the lookups fails - so, for the moment, revert to
768          * FS.FetchStatus for just the primary fid.
769          */
770         inode = ERR_PTR(-ERESTARTSYS);
771         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
772                 while (afs_select_fileserver(&fc)) {
773                         iget_data.cb_v_break = dvnode->volume->cb_v_break;
774                         iget_data.cb_s_break = fc.cbi->server->cb_s_break;
775                         scb = &cookie->statuses[0];
776                         afs_fs_fetch_status(&fc,
777                                             afs_v2net(dvnode),
778                                             cookie->fids,
779                                             scb,
780                                             NULL);
781                 }
782
783                 if (fc.ac.error == 0)
784                         cbi = afs_get_cb_interest(fc.cbi);
785                 inode = ERR_PTR(afs_end_vnode_operation(&fc));
786         }
787
788         if (IS_ERR(inode))
789                 goto out_c;
790
791 success:
792         /* Turn all the files into inodes and save the first one - which is the
793          * one we actually want.
794          */
795         scb = &cookie->statuses[0];
796         if (scb->status.abort_code != 0)
797                 inode = ERR_PTR(afs_abort_to_error(scb->status.abort_code));
798
799         for (i = 0; i < cookie->nr_fids; i++) {
800                 struct afs_status_cb *scb = &cookie->statuses[i];
801
802                 if (!scb->have_status && !scb->have_error)
803                         continue;
804
805                 if (cookie->inodes[i]) {
806                         afs_vnode_commit_status(&fc, AFS_FS_I(cookie->inodes[i]),
807                                                 scb->cb_break, NULL, scb);
808                         continue;
809                 }
810
811                 if (scb->status.abort_code != 0)
812                         continue;
813
814                 iget_data.fid = cookie->fids[i];
815                 ti = afs_iget(dir->i_sb, key, &iget_data, scb, cbi, dvnode);
816                 if (!IS_ERR(ti))
817                         afs_cache_permit(AFS_FS_I(ti), key,
818                                          0 /* Assume vnode->cb_break is 0 */ +
819                                          iget_data.cb_v_break,
820                                          scb);
821                 if (i == 0) {
822                         inode = ti;
823                 } else {
824                         if (!IS_ERR(ti))
825                                 iput(ti);
826                 }
827         }
828
829 out_c:
830         afs_put_cb_interest(afs_v2net(dvnode), cbi);
831         if (cookie->inodes) {
832                 for (i = 0; i < cookie->nr_fids; i++)
833                         iput(cookie->inodes[i]);
834                 kfree(cookie->inodes);
835         }
836 out_s:
837         kvfree(cookie->statuses);
838 out:
839         kfree(cookie);
840         return inode;
841 }
842
843 /*
844  * Look up an entry in a directory with @sys substitution.
845  */
846 static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry,
847                                        struct key *key)
848 {
849         struct afs_sysnames *subs;
850         struct afs_net *net = afs_i2net(dir);
851         struct dentry *ret;
852         char *buf, *p, *name;
853         int len, i;
854
855         _enter("");
856
857         ret = ERR_PTR(-ENOMEM);
858         p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL);
859         if (!buf)
860                 goto out_p;
861         if (dentry->d_name.len > 4) {
862                 memcpy(p, dentry->d_name.name, dentry->d_name.len - 4);
863                 p += dentry->d_name.len - 4;
864         }
865
866         /* There is an ordered list of substitutes that we have to try. */
867         read_lock(&net->sysnames_lock);
868         subs = net->sysnames;
869         refcount_inc(&subs->usage);
870         read_unlock(&net->sysnames_lock);
871
872         for (i = 0; i < subs->nr; i++) {
873                 name = subs->subs[i];
874                 len = dentry->d_name.len - 4 + strlen(name);
875                 if (len >= AFSNAMEMAX) {
876                         ret = ERR_PTR(-ENAMETOOLONG);
877                         goto out_s;
878                 }
879
880                 strcpy(p, name);
881                 ret = lookup_one_len(buf, dentry->d_parent, len);
882                 if (IS_ERR(ret) || d_is_positive(ret))
883                         goto out_s;
884                 dput(ret);
885         }
886
887         /* We don't want to d_add() the @sys dentry here as we don't want to
888          * the cached dentry to hide changes to the sysnames list.
889          */
890         ret = NULL;
891 out_s:
892         afs_put_sysnames(subs);
893         kfree(buf);
894 out_p:
895         key_put(key);
896         return ret;
897 }
898
899 /*
900  * look up an entry in a directory
901  */
902 static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
903                                  unsigned int flags)
904 {
905         struct afs_vnode *dvnode = AFS_FS_I(dir);
906         struct inode *inode;
907         struct dentry *d;
908         struct key *key;
909         int ret;
910
911         _enter("{%llx:%llu},%p{%pd},",
912                dvnode->fid.vid, dvnode->fid.vnode, dentry, dentry);
913
914         ASSERTCMP(d_inode(dentry), ==, NULL);
915
916         if (dentry->d_name.len >= AFSNAMEMAX) {
917                 _leave(" = -ENAMETOOLONG");
918                 return ERR_PTR(-ENAMETOOLONG);
919         }
920
921         if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) {
922                 _leave(" = -ESTALE");
923                 return ERR_PTR(-ESTALE);
924         }
925
926         key = afs_request_key(dvnode->volume->cell);
927         if (IS_ERR(key)) {
928                 _leave(" = %ld [key]", PTR_ERR(key));
929                 return ERR_CAST(key);
930         }
931
932         ret = afs_validate(dvnode, key);
933         if (ret < 0) {
934                 key_put(key);
935                 _leave(" = %d [val]", ret);
936                 return ERR_PTR(ret);
937         }
938
939         if (dentry->d_name.len >= 4 &&
940             dentry->d_name.name[dentry->d_name.len - 4] == '@' &&
941             dentry->d_name.name[dentry->d_name.len - 3] == 's' &&
942             dentry->d_name.name[dentry->d_name.len - 2] == 'y' &&
943             dentry->d_name.name[dentry->d_name.len - 1] == 's')
944                 return afs_lookup_atsys(dir, dentry, key);
945
946         afs_stat_v(dvnode, n_lookup);
947         inode = afs_do_lookup(dir, dentry, key);
948         key_put(key);
949         if (inode == ERR_PTR(-ENOENT)) {
950                 inode = afs_try_auto_mntpt(dentry, dir);
951         } else {
952                 dentry->d_fsdata =
953                         (void *)(unsigned long)dvnode->status.data_version;
954         }
955         d = d_splice_alias(inode, dentry);
956         if (!IS_ERR_OR_NULL(d)) {
957                 d->d_fsdata = dentry->d_fsdata;
958                 trace_afs_lookup(dvnode, &d->d_name,
959                                  inode ? AFS_FS_I(inode) : NULL);
960         } else {
961                 trace_afs_lookup(dvnode, &dentry->d_name,
962                                  IS_ERR_OR_NULL(inode) ? NULL
963                                  : AFS_FS_I(inode));
964         }
965         return d;
966 }
967
968 /*
969  * check that a dentry lookup hit has found a valid entry
970  * - NOTE! the hit can be a negative hit too, so we can't assume we have an
971  *   inode
972  */
973 static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
974 {
975         struct afs_vnode *vnode, *dir;
976         struct afs_fid uninitialized_var(fid);
977         struct dentry *parent;
978         struct inode *inode;
979         struct key *key;
980         afs_dataversion_t dir_version;
981         long de_version;
982         int ret;
983
984         if (flags & LOOKUP_RCU)
985                 return -ECHILD;
986
987         if (d_really_is_positive(dentry)) {
988                 vnode = AFS_FS_I(d_inode(dentry));
989                 _enter("{v={%llx:%llu} n=%pd fl=%lx},",
990                        vnode->fid.vid, vnode->fid.vnode, dentry,
991                        vnode->flags);
992         } else {
993                 _enter("{neg n=%pd}", dentry);
994         }
995
996         key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
997         if (IS_ERR(key))
998                 key = NULL;
999
1000         if (d_really_is_positive(dentry)) {
1001                 inode = d_inode(dentry);
1002                 if (inode) {
1003                         vnode = AFS_FS_I(inode);
1004                         afs_validate(vnode, key);
1005                         if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1006                                 goto out_bad;
1007                 }
1008         }
1009
1010         /* lock down the parent dentry so we can peer at it */
1011         parent = dget_parent(dentry);
1012         dir = AFS_FS_I(d_inode(parent));
1013
1014         /* validate the parent directory */
1015         afs_validate(dir, key);
1016
1017         if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
1018                 _debug("%pd: parent dir deleted", dentry);
1019                 goto out_bad_parent;
1020         }
1021
1022         /* We only need to invalidate a dentry if the server's copy changed
1023          * behind our back.  If we made the change, it's no problem.  Note that
1024          * on a 32-bit system, we only have 32 bits in the dentry to store the
1025          * version.
1026          */
1027         dir_version = dir->status.data_version;
1028         de_version = (long)dentry->d_fsdata;
1029         if (de_version == (long)dir_version)
1030                 goto out_valid_noupdate;
1031
1032         dir_version = dir->invalid_before;
1033         if (de_version - (long)dir_version >= 0)
1034                 goto out_valid;
1035
1036         _debug("dir modified");
1037         afs_stat_v(dir, n_reval);
1038
1039         /* search the directory for this vnode */
1040         ret = afs_do_lookup_one(&dir->vfs_inode, dentry, &fid, key, &dir_version);
1041         switch (ret) {
1042         case 0:
1043                 /* the filename maps to something */
1044                 if (d_really_is_negative(dentry))
1045                         goto out_bad_parent;
1046                 inode = d_inode(dentry);
1047                 if (is_bad_inode(inode)) {
1048                         printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
1049                                dentry);
1050                         goto out_bad_parent;
1051                 }
1052
1053                 vnode = AFS_FS_I(inode);
1054
1055                 /* if the vnode ID has changed, then the dirent points to a
1056                  * different file */
1057                 if (fid.vnode != vnode->fid.vnode) {
1058                         _debug("%pd: dirent changed [%llu != %llu]",
1059                                dentry, fid.vnode,
1060                                vnode->fid.vnode);
1061                         goto not_found;
1062                 }
1063
1064                 /* if the vnode ID uniqifier has changed, then the file has
1065                  * been deleted and replaced, and the original vnode ID has
1066                  * been reused */
1067                 if (fid.unique != vnode->fid.unique) {
1068                         _debug("%pd: file deleted (uq %u -> %u I:%u)",
1069                                dentry, fid.unique,
1070                                vnode->fid.unique,
1071                                vnode->vfs_inode.i_generation);
1072                         write_seqlock(&vnode->cb_lock);
1073                         set_bit(AFS_VNODE_DELETED, &vnode->flags);
1074                         write_sequnlock(&vnode->cb_lock);
1075                         goto not_found;
1076                 }
1077                 goto out_valid;
1078
1079         case -ENOENT:
1080                 /* the filename is unknown */
1081                 _debug("%pd: dirent not found", dentry);
1082                 if (d_really_is_positive(dentry))
1083                         goto not_found;
1084                 goto out_valid;
1085
1086         default:
1087                 _debug("failed to iterate dir %pd: %d",
1088                        parent, ret);
1089                 goto out_bad_parent;
1090         }
1091
1092 out_valid:
1093         dentry->d_fsdata = (void *)(unsigned long)dir_version;
1094 out_valid_noupdate:
1095         dput(parent);
1096         key_put(key);
1097         _leave(" = 1 [valid]");
1098         return 1;
1099
1100         /* the dirent, if it exists, now points to a different vnode */
1101 not_found:
1102         spin_lock(&dentry->d_lock);
1103         dentry->d_flags |= DCACHE_NFSFS_RENAMED;
1104         spin_unlock(&dentry->d_lock);
1105
1106 out_bad_parent:
1107         _debug("dropping dentry %pd2", dentry);
1108         dput(parent);
1109 out_bad:
1110         key_put(key);
1111
1112         _leave(" = 0 [bad]");
1113         return 0;
1114 }
1115
1116 /*
1117  * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
1118  * sleep)
1119  * - called from dput() when d_count is going to 0.
1120  * - return 1 to request dentry be unhashed, 0 otherwise
1121  */
1122 static int afs_d_delete(const struct dentry *dentry)
1123 {
1124         _enter("%pd", dentry);
1125
1126         if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1127                 goto zap;
1128
1129         if (d_really_is_positive(dentry) &&
1130             (test_bit(AFS_VNODE_DELETED,   &AFS_FS_I(d_inode(dentry))->flags) ||
1131              test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
1132                 goto zap;
1133
1134         _leave(" = 0 [keep]");
1135         return 0;
1136
1137 zap:
1138         _leave(" = 1 [zap]");
1139         return 1;
1140 }
1141
1142 /*
1143  * Clean up sillyrename files on dentry removal.
1144  */
1145 static void afs_d_iput(struct dentry *dentry, struct inode *inode)
1146 {
1147         if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1148                 afs_silly_iput(dentry, inode);
1149         iput(inode);
1150 }
1151
1152 /*
1153  * handle dentry release
1154  */
1155 void afs_d_release(struct dentry *dentry)
1156 {
1157         _enter("%pd", dentry);
1158 }
1159
1160 /*
1161  * Create a new inode for create/mkdir/symlink
1162  */
1163 static void afs_vnode_new_inode(struct afs_fs_cursor *fc,
1164                                 struct dentry *new_dentry,
1165                                 struct afs_iget_data *new_data,
1166                                 struct afs_status_cb *new_scb)
1167 {
1168         struct afs_vnode *vnode;
1169         struct inode *inode;
1170
1171         if (fc->ac.error < 0)
1172                 return;
1173
1174         inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key,
1175                          new_data, new_scb, fc->cbi, fc->vnode);
1176         if (IS_ERR(inode)) {
1177                 /* ENOMEM or EINTR at a really inconvenient time - just abandon
1178                  * the new directory on the server.
1179                  */
1180                 fc->ac.error = PTR_ERR(inode);
1181                 return;
1182         }
1183
1184         vnode = AFS_FS_I(inode);
1185         set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
1186         if (fc->ac.error == 0)
1187                 afs_cache_permit(vnode, fc->key, vnode->cb_break, new_scb);
1188         d_instantiate(new_dentry, inode);
1189 }
1190
1191 static void afs_prep_for_new_inode(struct afs_fs_cursor *fc,
1192                                    struct afs_iget_data *iget_data)
1193 {
1194         iget_data->volume = fc->vnode->volume;
1195         iget_data->cb_v_break = fc->vnode->volume->cb_v_break;
1196         iget_data->cb_s_break = fc->cbi->server->cb_s_break;
1197 }
1198
1199 /*
1200  * Note that a dentry got changed.  We need to set d_fsdata to the data version
1201  * number derived from the result of the operation.  It doesn't matter if
1202  * d_fsdata goes backwards as we'll just revalidate.
1203  */
1204 static void afs_update_dentry_version(struct afs_fs_cursor *fc,
1205                                       struct dentry *dentry,
1206                                       struct afs_status_cb *scb)
1207 {
1208         if (fc->ac.error == 0)
1209                 dentry->d_fsdata =
1210                         (void *)(unsigned long)scb->status.data_version;
1211 }
1212
1213 /*
1214  * create a directory on an AFS filesystem
1215  */
1216 static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
1217 {
1218         struct afs_iget_data iget_data;
1219         struct afs_status_cb *scb;
1220         struct afs_fs_cursor fc;
1221         struct afs_vnode *dvnode = AFS_FS_I(dir);
1222         struct key *key;
1223         int ret;
1224
1225         mode |= S_IFDIR;
1226
1227         _enter("{%llx:%llu},{%pd},%ho",
1228                dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1229
1230         ret = -ENOMEM;
1231         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1232         if (!scb)
1233                 goto error;
1234
1235         key = afs_request_key(dvnode->volume->cell);
1236         if (IS_ERR(key)) {
1237                 ret = PTR_ERR(key);
1238                 goto error_scb;
1239         }
1240
1241         ret = -ERESTARTSYS;
1242         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1243                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1244
1245                 while (afs_select_fileserver(&fc)) {
1246                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1247                         afs_prep_for_new_inode(&fc, &iget_data);
1248                         afs_fs_create(&fc, dentry->d_name.name, mode,
1249                                       &scb[0], &iget_data.fid, &scb[1]);
1250                 }
1251
1252                 afs_check_for_remote_deletion(&fc, dvnode);
1253                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1254                                         &data_version, &scb[0]);
1255                 afs_update_dentry_version(&fc, dentry, &scb[0]);
1256                 afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1257                 ret = afs_end_vnode_operation(&fc);
1258                 if (ret < 0)
1259                         goto error_key;
1260         } else {
1261                 goto error_key;
1262         }
1263
1264         if (ret == 0 &&
1265             test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1266                 afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1267                                  afs_edit_dir_for_create);
1268
1269         key_put(key);
1270         kfree(scb);
1271         _leave(" = 0");
1272         return 0;
1273
1274 error_key:
1275         key_put(key);
1276 error_scb:
1277         kfree(scb);
1278 error:
1279         d_drop(dentry);
1280         _leave(" = %d", ret);
1281         return ret;
1282 }
1283
1284 /*
1285  * Remove a subdir from a directory.
1286  */
1287 static void afs_dir_remove_subdir(struct dentry *dentry)
1288 {
1289         if (d_really_is_positive(dentry)) {
1290                 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1291
1292                 clear_nlink(&vnode->vfs_inode);
1293                 set_bit(AFS_VNODE_DELETED, &vnode->flags);
1294                 clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags);
1295                 clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
1296         }
1297 }
1298
1299 /*
1300  * remove a directory from an AFS filesystem
1301  */
1302 static int afs_rmdir(struct inode *dir, struct dentry *dentry)
1303 {
1304         struct afs_status_cb *scb;
1305         struct afs_fs_cursor fc;
1306         struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL;
1307         struct key *key;
1308         int ret;
1309
1310         _enter("{%llx:%llu},{%pd}",
1311                dvnode->fid.vid, dvnode->fid.vnode, dentry);
1312
1313         scb = kzalloc(sizeof(struct afs_status_cb), GFP_KERNEL);
1314         if (!scb)
1315                 return -ENOMEM;
1316
1317         key = afs_request_key(dvnode->volume->cell);
1318         if (IS_ERR(key)) {
1319                 ret = PTR_ERR(key);
1320                 goto error;
1321         }
1322
1323         /* Try to make sure we have a callback promise on the victim. */
1324         if (d_really_is_positive(dentry)) {
1325                 vnode = AFS_FS_I(d_inode(dentry));
1326                 ret = afs_validate(vnode, key);
1327                 if (ret < 0)
1328                         goto error_key;
1329         }
1330
1331         if (vnode) {
1332                 ret = down_write_killable(&vnode->rmdir_lock);
1333                 if (ret < 0)
1334                         goto error_key;
1335         }
1336
1337         ret = -ERESTARTSYS;
1338         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1339                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1340
1341                 while (afs_select_fileserver(&fc)) {
1342                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1343                         afs_fs_remove(&fc, vnode, dentry->d_name.name, true, scb);
1344                 }
1345
1346                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1347                                         &data_version, scb);
1348                 afs_update_dentry_version(&fc, dentry, scb);
1349                 ret = afs_end_vnode_operation(&fc);
1350                 if (ret == 0) {
1351                         afs_dir_remove_subdir(dentry);
1352                         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1353                                 afs_edit_dir_remove(dvnode, &dentry->d_name,
1354                                                     afs_edit_dir_for_rmdir);
1355                 }
1356         }
1357
1358         if (vnode)
1359                 up_write(&vnode->rmdir_lock);
1360 error_key:
1361         key_put(key);
1362 error:
1363         kfree(scb);
1364         return ret;
1365 }
1366
1367 /*
1368  * Remove a link to a file or symlink from a directory.
1369  *
1370  * If the file was not deleted due to excess hard links, the fileserver will
1371  * break the callback promise on the file - if it had one - before it returns
1372  * to us, and if it was deleted, it won't
1373  *
1374  * However, if we didn't have a callback promise outstanding, or it was
1375  * outstanding on a different server, then it won't break it either...
1376  */
1377 static int afs_dir_remove_link(struct afs_vnode *dvnode, struct dentry *dentry,
1378                                struct key *key)
1379 {
1380         int ret = 0;
1381
1382         if (d_really_is_positive(dentry)) {
1383                 struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1384
1385                 if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
1386                         /* Already done */
1387                 } else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
1388                         write_seqlock(&vnode->cb_lock);
1389                         drop_nlink(&vnode->vfs_inode);
1390                         if (vnode->vfs_inode.i_nlink == 0) {
1391                                 set_bit(AFS_VNODE_DELETED, &vnode->flags);
1392                                 __afs_break_callback(vnode, afs_cb_break_for_unlink);
1393                         }
1394                         write_sequnlock(&vnode->cb_lock);
1395                         ret = 0;
1396                 } else {
1397                         afs_break_callback(vnode, afs_cb_break_for_unlink);
1398
1399                         if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1400                                 kdebug("AFS_VNODE_DELETED");
1401
1402                         ret = afs_validate(vnode, key);
1403                         if (ret == -ESTALE)
1404                                 ret = 0;
1405                 }
1406                 _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret);
1407         }
1408
1409         return ret;
1410 }
1411
1412 /*
1413  * Remove a file or symlink from an AFS filesystem.
1414  */
1415 static int afs_unlink(struct inode *dir, struct dentry *dentry)
1416 {
1417         struct afs_fs_cursor fc;
1418         struct afs_status_cb *scb;
1419         struct afs_vnode *dvnode = AFS_FS_I(dir);
1420         struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1421         struct key *key;
1422         bool need_rehash = false;
1423         int ret;
1424
1425         _enter("{%llx:%llu},{%pd}",
1426                dvnode->fid.vid, dvnode->fid.vnode, dentry);
1427
1428         if (dentry->d_name.len >= AFSNAMEMAX)
1429                 return -ENAMETOOLONG;
1430
1431         ret = -ENOMEM;
1432         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1433         if (!scb)
1434                 goto error;
1435
1436         key = afs_request_key(dvnode->volume->cell);
1437         if (IS_ERR(key)) {
1438                 ret = PTR_ERR(key);
1439                 goto error_scb;
1440         }
1441
1442         /* Try to make sure we have a callback promise on the victim. */
1443         ret = afs_validate(vnode, key);
1444         if (ret < 0)
1445                 goto error_key;
1446
1447         spin_lock(&dentry->d_lock);
1448         if (d_count(dentry) > 1) {
1449                 spin_unlock(&dentry->d_lock);
1450                 /* Start asynchronous writeout of the inode */
1451                 write_inode_now(d_inode(dentry), 0);
1452                 ret = afs_sillyrename(dvnode, vnode, dentry, key);
1453                 goto error_key;
1454         }
1455         if (!d_unhashed(dentry)) {
1456                 /* Prevent a race with RCU lookup. */
1457                 __d_drop(dentry);
1458                 need_rehash = true;
1459         }
1460         spin_unlock(&dentry->d_lock);
1461
1462         ret = -ERESTARTSYS;
1463         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1464                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1465                 afs_dataversion_t data_version_2 = vnode->status.data_version;
1466
1467                 while (afs_select_fileserver(&fc)) {
1468                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1469                         fc.cb_break_2 = afs_calc_vnode_cb_break(vnode);
1470
1471                         if (test_bit(AFS_SERVER_FL_IS_YFS, &fc.cbi->server->flags) &&
1472                             !test_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags)) {
1473                                 yfs_fs_remove_file2(&fc, vnode, dentry->d_name.name,
1474                                                     &scb[0], &scb[1]);
1475                                 if (fc.ac.error != -ECONNABORTED ||
1476                                     fc.ac.abort_code != RXGEN_OPCODE)
1477                                         continue;
1478                                 set_bit(AFS_SERVER_FL_NO_RM2, &fc.cbi->server->flags);
1479                         }
1480
1481                         afs_fs_remove(&fc, vnode, dentry->d_name.name, false, &scb[0]);
1482                 }
1483
1484                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1485                                         &data_version, &scb[0]);
1486                 afs_vnode_commit_status(&fc, vnode, fc.cb_break_2,
1487                                         &data_version_2, &scb[1]);
1488                 afs_update_dentry_version(&fc, dentry, &scb[0]);
1489                 ret = afs_end_vnode_operation(&fc);
1490                 if (ret == 0 && !(scb[1].have_status || scb[1].have_error))
1491                         ret = afs_dir_remove_link(dvnode, dentry, key);
1492                 if (ret == 0 &&
1493                     test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1494                         afs_edit_dir_remove(dvnode, &dentry->d_name,
1495                                             afs_edit_dir_for_unlink);
1496         }
1497
1498         if (need_rehash && ret < 0 && ret != -ENOENT)
1499                 d_rehash(dentry);
1500
1501 error_key:
1502         key_put(key);
1503 error_scb:
1504         kfree(scb);
1505 error:
1506         _leave(" = %d", ret);
1507         return ret;
1508 }
1509
1510 /*
1511  * create a regular file on an AFS filesystem
1512  */
1513 static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
1514                       bool excl)
1515 {
1516         struct afs_iget_data iget_data;
1517         struct afs_fs_cursor fc;
1518         struct afs_status_cb *scb;
1519         struct afs_vnode *dvnode = AFS_FS_I(dir);
1520         struct key *key;
1521         int ret;
1522
1523         mode |= S_IFREG;
1524
1525         _enter("{%llx:%llu},{%pd},%ho,",
1526                dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1527
1528         ret = -ENAMETOOLONG;
1529         if (dentry->d_name.len >= AFSNAMEMAX)
1530                 goto error;
1531
1532         key = afs_request_key(dvnode->volume->cell);
1533         if (IS_ERR(key)) {
1534                 ret = PTR_ERR(key);
1535                 goto error;
1536         }
1537
1538         ret = -ENOMEM;
1539         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1540         if (!scb)
1541                 goto error_scb;
1542
1543         ret = -ERESTARTSYS;
1544         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1545                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1546
1547                 while (afs_select_fileserver(&fc)) {
1548                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1549                         afs_prep_for_new_inode(&fc, &iget_data);
1550                         afs_fs_create(&fc, dentry->d_name.name, mode,
1551                                       &scb[0], &iget_data.fid, &scb[1]);
1552                 }
1553
1554                 afs_check_for_remote_deletion(&fc, dvnode);
1555                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1556                                         &data_version, &scb[0]);
1557                 afs_update_dentry_version(&fc, dentry, &scb[0]);
1558                 afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1559                 ret = afs_end_vnode_operation(&fc);
1560                 if (ret < 0)
1561                         goto error_key;
1562         } else {
1563                 goto error_key;
1564         }
1565
1566         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1567                 afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1568                                  afs_edit_dir_for_create);
1569
1570         kfree(scb);
1571         key_put(key);
1572         _leave(" = 0");
1573         return 0;
1574
1575 error_scb:
1576         kfree(scb);
1577 error_key:
1578         key_put(key);
1579 error:
1580         d_drop(dentry);
1581         _leave(" = %d", ret);
1582         return ret;
1583 }
1584
1585 /*
1586  * create a hard link between files in an AFS filesystem
1587  */
1588 static int afs_link(struct dentry *from, struct inode *dir,
1589                     struct dentry *dentry)
1590 {
1591         struct afs_fs_cursor fc;
1592         struct afs_status_cb *scb;
1593         struct afs_vnode *dvnode = AFS_FS_I(dir);
1594         struct afs_vnode *vnode = AFS_FS_I(d_inode(from));
1595         struct key *key;
1596         int ret;
1597
1598         _enter("{%llx:%llu},{%llx:%llu},{%pd}",
1599                vnode->fid.vid, vnode->fid.vnode,
1600                dvnode->fid.vid, dvnode->fid.vnode,
1601                dentry);
1602
1603         ret = -ENAMETOOLONG;
1604         if (dentry->d_name.len >= AFSNAMEMAX)
1605                 goto error;
1606
1607         ret = -ENOMEM;
1608         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1609         if (!scb)
1610                 goto error;
1611
1612         key = afs_request_key(dvnode->volume->cell);
1613         if (IS_ERR(key)) {
1614                 ret = PTR_ERR(key);
1615                 goto error_scb;
1616         }
1617
1618         ret = -ERESTARTSYS;
1619         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1620                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1621
1622                 if (mutex_lock_interruptible_nested(&vnode->io_lock, 1) < 0) {
1623                         afs_end_vnode_operation(&fc);
1624                         goto error_key;
1625                 }
1626
1627                 while (afs_select_fileserver(&fc)) {
1628                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1629                         fc.cb_break_2 = afs_calc_vnode_cb_break(vnode);
1630                         afs_fs_link(&fc, vnode, dentry->d_name.name,
1631                                     &scb[0], &scb[1]);
1632                 }
1633
1634                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1635                                         &data_version, &scb[0]);
1636                 afs_vnode_commit_status(&fc, vnode, fc.cb_break_2,
1637                                         NULL, &scb[1]);
1638                 ihold(&vnode->vfs_inode);
1639                 afs_update_dentry_version(&fc, dentry, &scb[0]);
1640                 d_instantiate(dentry, &vnode->vfs_inode);
1641
1642                 mutex_unlock(&vnode->io_lock);
1643                 ret = afs_end_vnode_operation(&fc);
1644                 if (ret < 0)
1645                         goto error_key;
1646         } else {
1647                 goto error_key;
1648         }
1649
1650         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1651                 afs_edit_dir_add(dvnode, &dentry->d_name, &vnode->fid,
1652                                  afs_edit_dir_for_link);
1653
1654         key_put(key);
1655         kfree(scb);
1656         _leave(" = 0");
1657         return 0;
1658
1659 error_key:
1660         key_put(key);
1661 error_scb:
1662         kfree(scb);
1663 error:
1664         d_drop(dentry);
1665         _leave(" = %d", ret);
1666         return ret;
1667 }
1668
1669 /*
1670  * create a symlink in an AFS filesystem
1671  */
1672 static int afs_symlink(struct inode *dir, struct dentry *dentry,
1673                        const char *content)
1674 {
1675         struct afs_iget_data iget_data;
1676         struct afs_fs_cursor fc;
1677         struct afs_status_cb *scb;
1678         struct afs_vnode *dvnode = AFS_FS_I(dir);
1679         struct key *key;
1680         int ret;
1681
1682         _enter("{%llx:%llu},{%pd},%s",
1683                dvnode->fid.vid, dvnode->fid.vnode, dentry,
1684                content);
1685
1686         ret = -ENAMETOOLONG;
1687         if (dentry->d_name.len >= AFSNAMEMAX)
1688                 goto error;
1689
1690         ret = -EINVAL;
1691         if (strlen(content) >= AFSPATHMAX)
1692                 goto error;
1693
1694         ret = -ENOMEM;
1695         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1696         if (!scb)
1697                 goto error;
1698
1699         key = afs_request_key(dvnode->volume->cell);
1700         if (IS_ERR(key)) {
1701                 ret = PTR_ERR(key);
1702                 goto error_scb;
1703         }
1704
1705         ret = -ERESTARTSYS;
1706         if (afs_begin_vnode_operation(&fc, dvnode, key, true)) {
1707                 afs_dataversion_t data_version = dvnode->status.data_version + 1;
1708
1709                 while (afs_select_fileserver(&fc)) {
1710                         fc.cb_break = afs_calc_vnode_cb_break(dvnode);
1711                         afs_prep_for_new_inode(&fc, &iget_data);
1712                         afs_fs_symlink(&fc, dentry->d_name.name, content,
1713                                        &scb[0], &iget_data.fid, &scb[1]);
1714                 }
1715
1716                 afs_check_for_remote_deletion(&fc, dvnode);
1717                 afs_vnode_commit_status(&fc, dvnode, fc.cb_break,
1718                                         &data_version, &scb[0]);
1719                 afs_update_dentry_version(&fc, dentry, &scb[0]);
1720                 afs_vnode_new_inode(&fc, dentry, &iget_data, &scb[1]);
1721                 ret = afs_end_vnode_operation(&fc);
1722                 if (ret < 0)
1723                         goto error_key;
1724         } else {
1725                 goto error_key;
1726         }
1727
1728         if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1729                 afs_edit_dir_add(dvnode, &dentry->d_name, &iget_data.fid,
1730                                  afs_edit_dir_for_symlink);
1731
1732         key_put(key);
1733         kfree(scb);
1734         _leave(" = 0");
1735         return 0;
1736
1737 error_key:
1738         key_put(key);
1739 error_scb:
1740         kfree(scb);
1741 error:
1742         d_drop(dentry);
1743         _leave(" = %d", ret);
1744         return ret;
1745 }
1746
1747 /*
1748  * rename a file in an AFS filesystem and/or move it between directories
1749  */
1750 static int afs_rename(struct inode *old_dir, struct dentry *old_dentry,
1751                       struct inode *new_dir, struct dentry *new_dentry,
1752                       unsigned int flags)
1753 {
1754         struct afs_fs_cursor fc;
1755         struct afs_status_cb *scb;
1756         struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
1757         struct dentry *tmp = NULL, *rehash = NULL;
1758         struct inode *new_inode;
1759         struct key *key;
1760         bool new_negative = d_is_negative(new_dentry);
1761         int ret;
1762
1763         if (flags)
1764                 return -EINVAL;
1765
1766         /* Don't allow silly-rename files be moved around. */
1767         if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED)
1768                 return -EINVAL;
1769
1770         vnode = AFS_FS_I(d_inode(old_dentry));
1771         orig_dvnode = AFS_FS_I(old_dir);
1772         new_dvnode = AFS_FS_I(new_dir);
1773
1774         _enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%pd}",
1775                orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
1776                vnode->fid.vid, vnode->fid.vnode,
1777                new_dvnode->fid.vid, new_dvnode->fid.vnode,
1778                new_dentry);
1779
1780         ret = -ENOMEM;
1781         scb = kcalloc(2, sizeof(struct afs_status_cb), GFP_KERNEL);
1782         if (!scb)
1783                 goto error;
1784
1785         key = afs_request_key(orig_dvnode->volume->cell);
1786         if (IS_ERR(key)) {
1787                 ret = PTR_ERR(key);
1788                 goto error_scb;
1789         }
1790
1791         /* For non-directories, check whether the target is busy and if so,
1792          * make a copy of the dentry and then do a silly-rename.  If the
1793          * silly-rename succeeds, the copied dentry is hashed and becomes the
1794          * new target.
1795          */
1796         if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) {
1797                 /* To prevent any new references to the target during the
1798                  * rename, we unhash the dentry in advance.
1799                  */
1800                 if (!d_unhashed(new_dentry)) {
1801                         d_drop(new_dentry);
1802                         rehash = new_dentry;
1803                 }
1804
1805                 if (d_count(new_dentry) > 2) {
1806                         /* copy the target dentry's name */
1807                         ret = -ENOMEM;
1808                         tmp = d_alloc(new_dentry->d_parent,
1809                                       &new_dentry->d_name);
1810                         if (!tmp)
1811                                 goto error_rehash;
1812
1813                         ret = afs_sillyrename(new_dvnode,
1814                                               AFS_FS_I(d_inode(new_dentry)),
1815                                               new_dentry, key);
1816                         if (ret)
1817                                 goto error_rehash;
1818
1819                         new_dentry = tmp;
1820                         rehash = NULL;
1821                         new_negative = true;
1822                 }
1823         }
1824
1825         /* This bit is potentially nasty as there's a potential race with
1826          * afs_d_revalidate{,_rcu}().  We have to change d_fsdata on the dentry
1827          * to reflect it's new parent's new data_version after the op, but
1828          * d_revalidate may see old_dentry between the op having taken place
1829          * and the version being updated.
1830          *
1831          * So drop the old_dentry for now to make other threads go through
1832          * lookup instead - which we hold a lock against.
1833          */
1834         d_drop(old_dentry);
1835
1836         ret = -ERESTARTSYS;
1837         if (afs_begin_vnode_operation(&fc, orig_dvnode, key, true)) {
1838                 afs_dataversion_t orig_data_version;
1839                 afs_dataversion_t new_data_version;
1840                 struct afs_status_cb *new_scb = &scb[1];
1841
1842                 orig_data_version = orig_dvnode->status.data_version + 1;
1843
1844                 if (orig_dvnode != new_dvnode) {
1845                         if (mutex_lock_interruptible_nested(&new_dvnode->io_lock, 1) < 0) {
1846                                 afs_end_vnode_operation(&fc);
1847                                 goto error_rehash_old;
1848                         }
1849                         new_data_version = new_dvnode->status.data_version + 1;
1850                 } else {
1851                         new_data_version = orig_data_version;
1852                         new_scb = &scb[0];
1853                 }
1854
1855                 while (afs_select_fileserver(&fc)) {
1856                         fc.cb_break = afs_calc_vnode_cb_break(orig_dvnode);
1857                         fc.cb_break_2 = afs_calc_vnode_cb_break(new_dvnode);
1858                         afs_fs_rename(&fc, old_dentry->d_name.name,
1859                                       new_dvnode, new_dentry->d_name.name,
1860                                       &scb[0], new_scb);
1861                 }
1862
1863                 afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break,
1864                                         &orig_data_version, &scb[0]);
1865                 if (new_dvnode != orig_dvnode) {
1866                         afs_vnode_commit_status(&fc, new_dvnode, fc.cb_break_2,
1867                                                 &new_data_version, &scb[1]);
1868                         mutex_unlock(&new_dvnode->io_lock);
1869                 }
1870                 ret = afs_end_vnode_operation(&fc);
1871                 if (ret < 0)
1872                         goto error_rehash_old;
1873         }
1874
1875         if (ret == 0) {
1876                 if (rehash)
1877                         d_rehash(rehash);
1878                 if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags))
1879                     afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
1880                                         afs_edit_dir_for_rename_0);
1881
1882                 if (!new_negative &&
1883                     test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
1884                         afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
1885                                             afs_edit_dir_for_rename_1);
1886
1887                 if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags))
1888                         afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
1889                                          &vnode->fid, afs_edit_dir_for_rename_2);
1890
1891                 new_inode = d_inode(new_dentry);
1892                 if (new_inode) {
1893                         spin_lock(&new_inode->i_lock);
1894                         if (new_inode->i_nlink > 0)
1895                                 drop_nlink(new_inode);
1896                         spin_unlock(&new_inode->i_lock);
1897                 }
1898
1899                 /* Now we can update d_fsdata on the dentries to reflect their
1900                  * new parent's data_version.
1901                  *
1902                  * Note that if we ever implement RENAME_EXCHANGE, we'll have
1903                  * to update both dentries with opposing dir versions.
1904                  */
1905                 if (new_dvnode != orig_dvnode) {
1906                         afs_update_dentry_version(&fc, old_dentry, &scb[1]);
1907                         afs_update_dentry_version(&fc, new_dentry, &scb[1]);
1908                 } else {
1909                         afs_update_dentry_version(&fc, old_dentry, &scb[0]);
1910                         afs_update_dentry_version(&fc, new_dentry, &scb[0]);
1911                 }
1912                 d_move(old_dentry, new_dentry);
1913                 goto error_tmp;
1914         }
1915
1916 error_rehash_old:
1917         d_rehash(new_dentry);
1918 error_rehash:
1919         if (rehash)
1920                 d_rehash(rehash);
1921 error_tmp:
1922         if (tmp)
1923                 dput(tmp);
1924         key_put(key);
1925 error_scb:
1926         kfree(scb);
1927 error:
1928         _leave(" = %d", ret);
1929         return ret;
1930 }
1931
1932 /*
1933  * Release a directory page and clean up its private state if it's not busy
1934  * - return true if the page can now be released, false if not
1935  */
1936 static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags)
1937 {
1938         struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
1939
1940         _enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, page->index);
1941
1942         set_page_private(page, 0);
1943         ClearPagePrivate(page);
1944
1945         /* The directory will need reloading. */
1946         if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1947                 afs_stat_v(dvnode, n_relpg);
1948         return 1;
1949 }
1950
1951 /*
1952  * invalidate part or all of a page
1953  * - release a page and clean up its private data if offset is 0 (indicating
1954  *   the entire page)
1955  */
1956 static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
1957                                    unsigned int length)
1958 {
1959         struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
1960
1961         _enter("{%lu},%u,%u", page->index, offset, length);
1962
1963         BUG_ON(!PageLocked(page));
1964
1965         /* The directory will need reloading. */
1966         if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
1967                 afs_stat_v(dvnode, n_inval);
1968
1969         /* we clean up only if the entire page is being invalidated */
1970         if (offset == 0 && length == PAGE_SIZE) {
1971                 set_page_private(page, 0);
1972                 ClearPagePrivate(page);
1973         }
1974 }