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1 #include "ceph_debug.h"
2
3 #include <linux/module.h>
4 #include <linux/fs.h>
5 #include <linux/smp_lock.h>
6 #include <linux/slab.h>
7 #include <linux/string.h>
8 #include <linux/uaccess.h>
9 #include <linux/kernel.h>
10 #include <linux/namei.h>
11 #include <linux/writeback.h>
12 #include <linux/vmalloc.h>
13 #include <linux/pagevec.h>
14
15 #include "super.h"
16 #include "decode.h"
17
18 /*
19  * Ceph inode operations
20  *
21  * Implement basic inode helpers (get, alloc) and inode ops (getattr,
22  * setattr, etc.), xattr helpers, and helpers for assimilating
23  * metadata returned by the MDS into our cache.
24  *
25  * Also define helpers for doing asynchronous writeback, invalidation,
26  * and truncation for the benefit of those who can't afford to block
27  * (typically because they are in the message handler path).
28  */
29
30 static const struct inode_operations ceph_symlink_iops;
31
32 static void ceph_invalidate_work(struct work_struct *work);
33 static void ceph_writeback_work(struct work_struct *work);
34 static void ceph_vmtruncate_work(struct work_struct *work);
35
36 /*
37  * find or create an inode, given the ceph ino number
38  */
39 struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino)
40 {
41         struct inode *inode;
42         ino_t t = ceph_vino_to_ino(vino);
43
44         inode = iget5_locked(sb, t, ceph_ino_compare, ceph_set_ino_cb, &vino);
45         if (inode == NULL)
46                 return ERR_PTR(-ENOMEM);
47         if (inode->i_state & I_NEW) {
48                 dout("get_inode created new inode %p %llx.%llx ino %llx\n",
49                      inode, ceph_vinop(inode), (u64)inode->i_ino);
50                 unlock_new_inode(inode);
51         }
52
53         dout("get_inode on %lu=%llx.%llx got %p\n", inode->i_ino, vino.ino,
54              vino.snap, inode);
55         return inode;
56 }
57
58 /*
59  * get/constuct snapdir inode for a given directory
60  */
61 struct inode *ceph_get_snapdir(struct inode *parent)
62 {
63         struct ceph_vino vino = {
64                 .ino = ceph_ino(parent),
65                 .snap = CEPH_SNAPDIR,
66         };
67         struct inode *inode = ceph_get_inode(parent->i_sb, vino);
68         struct ceph_inode_info *ci = ceph_inode(inode);
69
70         BUG_ON(!S_ISDIR(parent->i_mode));
71         if (IS_ERR(inode))
72                 return inode;
73         inode->i_mode = parent->i_mode;
74         inode->i_uid = parent->i_uid;
75         inode->i_gid = parent->i_gid;
76         inode->i_op = &ceph_dir_iops;
77         inode->i_fop = &ceph_dir_fops;
78         ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
79         ci->i_rbytes = 0;
80         return inode;
81 }
82
83 const struct inode_operations ceph_file_iops = {
84         .permission = ceph_permission,
85         .setattr = ceph_setattr,
86         .getattr = ceph_getattr,
87         .setxattr = ceph_setxattr,
88         .getxattr = ceph_getxattr,
89         .listxattr = ceph_listxattr,
90         .removexattr = ceph_removexattr,
91 };
92
93
94 /*
95  * We use a 'frag tree' to keep track of the MDS's directory fragments
96  * for a given inode (usually there is just a single fragment).  We
97  * need to know when a child frag is delegated to a new MDS, or when
98  * it is flagged as replicated, so we can direct our requests
99  * accordingly.
100  */
101
102 /*
103  * find/create a frag in the tree
104  */
105 static struct ceph_inode_frag *__get_or_create_frag(struct ceph_inode_info *ci,
106                                                     u32 f)
107 {
108         struct rb_node **p;
109         struct rb_node *parent = NULL;
110         struct ceph_inode_frag *frag;
111         int c;
112
113         p = &ci->i_fragtree.rb_node;
114         while (*p) {
115                 parent = *p;
116                 frag = rb_entry(parent, struct ceph_inode_frag, node);
117                 c = ceph_frag_compare(f, frag->frag);
118                 if (c < 0)
119                         p = &(*p)->rb_left;
120                 else if (c > 0)
121                         p = &(*p)->rb_right;
122                 else
123                         return frag;
124         }
125
126         frag = kmalloc(sizeof(*frag), GFP_NOFS);
127         if (!frag) {
128                 pr_err("__get_or_create_frag ENOMEM on %p %llx.%llx "
129                        "frag %x\n", &ci->vfs_inode,
130                        ceph_vinop(&ci->vfs_inode), f);
131                 return ERR_PTR(-ENOMEM);
132         }
133         frag->frag = f;
134         frag->split_by = 0;
135         frag->mds = -1;
136         frag->ndist = 0;
137
138         rb_link_node(&frag->node, parent, p);
139         rb_insert_color(&frag->node, &ci->i_fragtree);
140
141         dout("get_or_create_frag added %llx.%llx frag %x\n",
142              ceph_vinop(&ci->vfs_inode), f);
143         return frag;
144 }
145
146 /*
147  * find a specific frag @f
148  */
149 struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci, u32 f)
150 {
151         struct rb_node *n = ci->i_fragtree.rb_node;
152
153         while (n) {
154                 struct ceph_inode_frag *frag =
155                         rb_entry(n, struct ceph_inode_frag, node);
156                 int c = ceph_frag_compare(f, frag->frag);
157                 if (c < 0)
158                         n = n->rb_left;
159                 else if (c > 0)
160                         n = n->rb_right;
161                 else
162                         return frag;
163         }
164         return NULL;
165 }
166
167 /*
168  * Choose frag containing the given value @v.  If @pfrag is
169  * specified, copy the frag delegation info to the caller if
170  * it is present.
171  */
172 u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
173                      struct ceph_inode_frag *pfrag,
174                      int *found)
175 {
176         u32 t = ceph_frag_make(0, 0);
177         struct ceph_inode_frag *frag;
178         unsigned nway, i;
179         u32 n;
180
181         if (found)
182                 *found = 0;
183
184         mutex_lock(&ci->i_fragtree_mutex);
185         while (1) {
186                 WARN_ON(!ceph_frag_contains_value(t, v));
187                 frag = __ceph_find_frag(ci, t);
188                 if (!frag)
189                         break; /* t is a leaf */
190                 if (frag->split_by == 0) {
191                         if (pfrag)
192                                 memcpy(pfrag, frag, sizeof(*pfrag));
193                         if (found)
194                                 *found = 1;
195                         break;
196                 }
197
198                 /* choose child */
199                 nway = 1 << frag->split_by;
200                 dout("choose_frag(%x) %x splits by %d (%d ways)\n", v, t,
201                      frag->split_by, nway);
202                 for (i = 0; i < nway; i++) {
203                         n = ceph_frag_make_child(t, frag->split_by, i);
204                         if (ceph_frag_contains_value(n, v)) {
205                                 t = n;
206                                 break;
207                         }
208                 }
209                 BUG_ON(i == nway);
210         }
211         dout("choose_frag(%x) = %x\n", v, t);
212
213         mutex_unlock(&ci->i_fragtree_mutex);
214         return t;
215 }
216
217 /*
218  * Process dirfrag (delegation) info from the mds.  Include leaf
219  * fragment in tree ONLY if ndist > 0.  Otherwise, only
220  * branches/splits are included in i_fragtree)
221  */
222 static int ceph_fill_dirfrag(struct inode *inode,
223                              struct ceph_mds_reply_dirfrag *dirinfo)
224 {
225         struct ceph_inode_info *ci = ceph_inode(inode);
226         struct ceph_inode_frag *frag;
227         u32 id = le32_to_cpu(dirinfo->frag);
228         int mds = le32_to_cpu(dirinfo->auth);
229         int ndist = le32_to_cpu(dirinfo->ndist);
230         int i;
231         int err = 0;
232
233         mutex_lock(&ci->i_fragtree_mutex);
234         if (ndist == 0) {
235                 /* no delegation info needed. */
236                 frag = __ceph_find_frag(ci, id);
237                 if (!frag)
238                         goto out;
239                 if (frag->split_by == 0) {
240                         /* tree leaf, remove */
241                         dout("fill_dirfrag removed %llx.%llx frag %x"
242                              " (no ref)\n", ceph_vinop(inode), id);
243                         rb_erase(&frag->node, &ci->i_fragtree);
244                         kfree(frag);
245                 } else {
246                         /* tree branch, keep and clear */
247                         dout("fill_dirfrag cleared %llx.%llx frag %x"
248                              " referral\n", ceph_vinop(inode), id);
249                         frag->mds = -1;
250                         frag->ndist = 0;
251                 }
252                 goto out;
253         }
254
255
256         /* find/add this frag to store mds delegation info */
257         frag = __get_or_create_frag(ci, id);
258         if (IS_ERR(frag)) {
259                 /* this is not the end of the world; we can continue
260                    with bad/inaccurate delegation info */
261                 pr_err("fill_dirfrag ENOMEM on mds ref %llx.%llx fg %x\n",
262                        ceph_vinop(inode), le32_to_cpu(dirinfo->frag));
263                 err = -ENOMEM;
264                 goto out;
265         }
266
267         frag->mds = mds;
268         frag->ndist = min_t(u32, ndist, CEPH_MAX_DIRFRAG_REP);
269         for (i = 0; i < frag->ndist; i++)
270                 frag->dist[i] = le32_to_cpu(dirinfo->dist[i]);
271         dout("fill_dirfrag %llx.%llx frag %x ndist=%d\n",
272              ceph_vinop(inode), frag->frag, frag->ndist);
273
274 out:
275         mutex_unlock(&ci->i_fragtree_mutex);
276         return err;
277 }
278
279
280 /*
281  * initialize a newly allocated inode.
282  */
283 struct inode *ceph_alloc_inode(struct super_block *sb)
284 {
285         struct ceph_inode_info *ci;
286         int i;
287
288         ci = kmem_cache_alloc(ceph_inode_cachep, GFP_NOFS);
289         if (!ci)
290                 return NULL;
291
292         dout("alloc_inode %p\n", &ci->vfs_inode);
293
294         ci->i_version = 0;
295         ci->i_time_warp_seq = 0;
296         ci->i_ceph_flags = 0;
297         ci->i_release_count = 0;
298         ci->i_symlink = NULL;
299
300         ci->i_fragtree = RB_ROOT;
301         mutex_init(&ci->i_fragtree_mutex);
302
303         ci->i_xattrs.blob = NULL;
304         ci->i_xattrs.prealloc_blob = NULL;
305         ci->i_xattrs.dirty = false;
306         ci->i_xattrs.index = RB_ROOT;
307         ci->i_xattrs.count = 0;
308         ci->i_xattrs.names_size = 0;
309         ci->i_xattrs.vals_size = 0;
310         ci->i_xattrs.version = 0;
311         ci->i_xattrs.index_version = 0;
312
313         ci->i_caps = RB_ROOT;
314         ci->i_auth_cap = NULL;
315         ci->i_dirty_caps = 0;
316         ci->i_flushing_caps = 0;
317         INIT_LIST_HEAD(&ci->i_dirty_item);
318         INIT_LIST_HEAD(&ci->i_flushing_item);
319         ci->i_cap_flush_seq = 0;
320         ci->i_cap_flush_last_tid = 0;
321         memset(&ci->i_cap_flush_tid, 0, sizeof(ci->i_cap_flush_tid));
322         init_waitqueue_head(&ci->i_cap_wq);
323         ci->i_hold_caps_min = 0;
324         ci->i_hold_caps_max = 0;
325         INIT_LIST_HEAD(&ci->i_cap_delay_list);
326         ci->i_cap_exporting_mds = 0;
327         ci->i_cap_exporting_mseq = 0;
328         ci->i_cap_exporting_issued = 0;
329         INIT_LIST_HEAD(&ci->i_cap_snaps);
330         ci->i_head_snapc = NULL;
331         ci->i_snap_caps = 0;
332
333         for (i = 0; i < CEPH_FILE_MODE_NUM; i++)
334                 ci->i_nr_by_mode[i] = 0;
335
336         ci->i_truncate_seq = 0;
337         ci->i_truncate_size = 0;
338         ci->i_truncate_pending = 0;
339
340         ci->i_max_size = 0;
341         ci->i_reported_size = 0;
342         ci->i_wanted_max_size = 0;
343         ci->i_requested_max_size = 0;
344
345         ci->i_pin_ref = 0;
346         ci->i_rd_ref = 0;
347         ci->i_rdcache_ref = 0;
348         ci->i_wr_ref = 0;
349         ci->i_wrbuffer_ref = 0;
350         ci->i_wrbuffer_ref_head = 0;
351         ci->i_shared_gen = 0;
352         ci->i_rdcache_gen = 0;
353         ci->i_rdcache_revoking = 0;
354
355         INIT_LIST_HEAD(&ci->i_unsafe_writes);
356         INIT_LIST_HEAD(&ci->i_unsafe_dirops);
357         spin_lock_init(&ci->i_unsafe_lock);
358
359         ci->i_snap_realm = NULL;
360         INIT_LIST_HEAD(&ci->i_snap_realm_item);
361         INIT_LIST_HEAD(&ci->i_snap_flush_item);
362
363         INIT_WORK(&ci->i_wb_work, ceph_writeback_work);
364         INIT_WORK(&ci->i_pg_inv_work, ceph_invalidate_work);
365
366         INIT_WORK(&ci->i_vmtruncate_work, ceph_vmtruncate_work);
367
368         return &ci->vfs_inode;
369 }
370
371 void ceph_destroy_inode(struct inode *inode)
372 {
373         struct ceph_inode_info *ci = ceph_inode(inode);
374         struct ceph_inode_frag *frag;
375         struct rb_node *n;
376
377         dout("destroy_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
378
379         ceph_queue_caps_release(inode);
380
381         /*
382          * we may still have a snap_realm reference if there are stray
383          * caps in i_cap_exporting_issued or i_snap_caps.
384          */
385         if (ci->i_snap_realm) {
386                 struct ceph_mds_client *mdsc =
387                         &ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
388                 struct ceph_snap_realm *realm = ci->i_snap_realm;
389
390                 dout(" dropping residual ref to snap realm %p\n", realm);
391                 spin_lock(&realm->inodes_with_caps_lock);
392                 list_del_init(&ci->i_snap_realm_item);
393                 spin_unlock(&realm->inodes_with_caps_lock);
394                 ceph_put_snap_realm(mdsc, realm);
395         }
396
397         kfree(ci->i_symlink);
398         while ((n = rb_first(&ci->i_fragtree)) != NULL) {
399                 frag = rb_entry(n, struct ceph_inode_frag, node);
400                 rb_erase(n, &ci->i_fragtree);
401                 kfree(frag);
402         }
403
404         __ceph_destroy_xattrs(ci);
405         if (ci->i_xattrs.blob)
406                 ceph_buffer_put(ci->i_xattrs.blob);
407         if (ci->i_xattrs.prealloc_blob)
408                 ceph_buffer_put(ci->i_xattrs.prealloc_blob);
409
410         kmem_cache_free(ceph_inode_cachep, ci);
411 }
412
413
414 /*
415  * Helpers to fill in size, ctime, mtime, and atime.  We have to be
416  * careful because either the client or MDS may have more up to date
417  * info, depending on which capabilities are held, and whether
418  * time_warp_seq or truncate_seq have increased.  (Ordinarily, mtime
419  * and size are monotonically increasing, except when utimes() or
420  * truncate() increments the corresponding _seq values.)
421  */
422 int ceph_fill_file_size(struct inode *inode, int issued,
423                         u32 truncate_seq, u64 truncate_size, u64 size)
424 {
425         struct ceph_inode_info *ci = ceph_inode(inode);
426         int queue_trunc = 0;
427
428         if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) > 0 ||
429             (truncate_seq == ci->i_truncate_seq && size > inode->i_size)) {
430                 dout("size %lld -> %llu\n", inode->i_size, size);
431                 inode->i_size = size;
432                 inode->i_blocks = (size + (1<<9) - 1) >> 9;
433                 ci->i_reported_size = size;
434                 if (truncate_seq != ci->i_truncate_seq) {
435                         dout("truncate_seq %u -> %u\n",
436                              ci->i_truncate_seq, truncate_seq);
437                         ci->i_truncate_seq = truncate_seq;
438                         /*
439                          * If we hold relevant caps, or in the case where we're
440                          * not the only client referencing this file and we
441                          * don't hold those caps, then we need to check whether
442                          * the file is either opened or mmaped
443                          */
444                         if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_RD|
445                                        CEPH_CAP_FILE_WR|CEPH_CAP_FILE_BUFFER|
446                                        CEPH_CAP_FILE_EXCL|
447                                        CEPH_CAP_FILE_LAZYIO)) ||
448                             mapping_mapped(inode->i_mapping) ||
449                             __ceph_caps_file_wanted(ci)) {
450                                 ci->i_truncate_pending++;
451                                 queue_trunc = 1;
452                         }
453                 }
454         }
455         if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) >= 0 &&
456             ci->i_truncate_size != truncate_size) {
457                 dout("truncate_size %lld -> %llu\n", ci->i_truncate_size,
458                      truncate_size);
459                 ci->i_truncate_size = truncate_size;
460         }
461         return queue_trunc;
462 }
463
464 void ceph_fill_file_time(struct inode *inode, int issued,
465                          u64 time_warp_seq, struct timespec *ctime,
466                          struct timespec *mtime, struct timespec *atime)
467 {
468         struct ceph_inode_info *ci = ceph_inode(inode);
469         int warn = 0;
470
471         if (issued & (CEPH_CAP_FILE_EXCL|
472                       CEPH_CAP_FILE_WR|
473                       CEPH_CAP_FILE_BUFFER)) {
474                 if (timespec_compare(ctime, &inode->i_ctime) > 0) {
475                         dout("ctime %ld.%09ld -> %ld.%09ld inc w/ cap\n",
476                              inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
477                              ctime->tv_sec, ctime->tv_nsec);
478                         inode->i_ctime = *ctime;
479                 }
480                 if (ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) > 0) {
481                         /* the MDS did a utimes() */
482                         dout("mtime %ld.%09ld -> %ld.%09ld "
483                              "tw %d -> %d\n",
484                              inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
485                              mtime->tv_sec, mtime->tv_nsec,
486                              ci->i_time_warp_seq, (int)time_warp_seq);
487
488                         inode->i_mtime = *mtime;
489                         inode->i_atime = *atime;
490                         ci->i_time_warp_seq = time_warp_seq;
491                 } else if (time_warp_seq == ci->i_time_warp_seq) {
492                         /* nobody did utimes(); take the max */
493                         if (timespec_compare(mtime, &inode->i_mtime) > 0) {
494                                 dout("mtime %ld.%09ld -> %ld.%09ld inc\n",
495                                      inode->i_mtime.tv_sec,
496                                      inode->i_mtime.tv_nsec,
497                                      mtime->tv_sec, mtime->tv_nsec);
498                                 inode->i_mtime = *mtime;
499                         }
500                         if (timespec_compare(atime, &inode->i_atime) > 0) {
501                                 dout("atime %ld.%09ld -> %ld.%09ld inc\n",
502                                      inode->i_atime.tv_sec,
503                                      inode->i_atime.tv_nsec,
504                                      atime->tv_sec, atime->tv_nsec);
505                                 inode->i_atime = *atime;
506                         }
507                 } else if (issued & CEPH_CAP_FILE_EXCL) {
508                         /* we did a utimes(); ignore mds values */
509                 } else {
510                         warn = 1;
511                 }
512         } else {
513                 /* we have no write caps; whatever the MDS says is true */
514                 if (ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) >= 0) {
515                         inode->i_ctime = *ctime;
516                         inode->i_mtime = *mtime;
517                         inode->i_atime = *atime;
518                         ci->i_time_warp_seq = time_warp_seq;
519                 } else {
520                         warn = 1;
521                 }
522         }
523         if (warn) /* time_warp_seq shouldn't go backwards */
524                 dout("%p mds time_warp_seq %llu < %u\n",
525                      inode, time_warp_seq, ci->i_time_warp_seq);
526 }
527
528 /*
529  * Populate an inode based on info from mds.  May be called on new or
530  * existing inodes.
531  */
532 static int fill_inode(struct inode *inode,
533                       struct ceph_mds_reply_info_in *iinfo,
534                       struct ceph_mds_reply_dirfrag *dirinfo,
535                       struct ceph_mds_session *session,
536                       unsigned long ttl_from, int cap_fmode,
537                       struct ceph_cap_reservation *caps_reservation)
538 {
539         struct ceph_mds_reply_inode *info = iinfo->in;
540         struct ceph_inode_info *ci = ceph_inode(inode);
541         int i;
542         int issued, implemented;
543         struct timespec mtime, atime, ctime;
544         u32 nsplits;
545         struct ceph_buffer *xattr_blob = NULL;
546         int err = 0;
547         int queue_trunc = 0;
548
549         dout("fill_inode %p ino %llx.%llx v %llu had %llu\n",
550              inode, ceph_vinop(inode), le64_to_cpu(info->version),
551              ci->i_version);
552
553         /*
554          * prealloc xattr data, if it looks like we'll need it.  only
555          * if len > 4 (meaning there are actually xattrs; the first 4
556          * bytes are the xattr count).
557          */
558         if (iinfo->xattr_len > 4) {
559                 xattr_blob = ceph_buffer_new(iinfo->xattr_len, GFP_NOFS);
560                 if (!xattr_blob)
561                         pr_err("fill_inode ENOMEM xattr blob %d bytes\n",
562                                iinfo->xattr_len);
563         }
564
565         spin_lock(&inode->i_lock);
566
567         /*
568          * provided version will be odd if inode value is projected,
569          * even if stable.  skip the update if we have a newer info
570          * (e.g., due to inode info racing form multiple MDSs), or if
571          * we are getting projected (unstable) inode info.
572          */
573         if (le64_to_cpu(info->version) > 0 &&
574             (ci->i_version & ~1) > le64_to_cpu(info->version))
575                 goto no_change;
576
577         issued = __ceph_caps_issued(ci, &implemented);
578         issued |= implemented | __ceph_caps_dirty(ci);
579
580         /* update inode */
581         ci->i_version = le64_to_cpu(info->version);
582         inode->i_version++;
583         inode->i_rdev = le32_to_cpu(info->rdev);
584
585         if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
586                 inode->i_mode = le32_to_cpu(info->mode);
587                 inode->i_uid = le32_to_cpu(info->uid);
588                 inode->i_gid = le32_to_cpu(info->gid);
589                 dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
590                      inode->i_uid, inode->i_gid);
591         }
592
593         if ((issued & CEPH_CAP_LINK_EXCL) == 0)
594                 inode->i_nlink = le32_to_cpu(info->nlink);
595
596         /* be careful with mtime, atime, size */
597         ceph_decode_timespec(&atime, &info->atime);
598         ceph_decode_timespec(&mtime, &info->mtime);
599         ceph_decode_timespec(&ctime, &info->ctime);
600         queue_trunc = ceph_fill_file_size(inode, issued,
601                                           le32_to_cpu(info->truncate_seq),
602                                           le64_to_cpu(info->truncate_size),
603                                           le64_to_cpu(info->size));
604         ceph_fill_file_time(inode, issued,
605                             le32_to_cpu(info->time_warp_seq),
606                             &ctime, &mtime, &atime);
607
608         ci->i_max_size = le64_to_cpu(info->max_size);
609         ci->i_layout = info->layout;
610         inode->i_blkbits = fls(le32_to_cpu(info->layout.fl_stripe_unit)) - 1;
611
612         /* xattrs */
613         /* note that if i_xattrs.len <= 4, i_xattrs.data will still be NULL. */
614         if ((issued & CEPH_CAP_XATTR_EXCL) == 0 &&
615             le64_to_cpu(info->xattr_version) > ci->i_xattrs.version) {
616                 if (ci->i_xattrs.blob)
617                         ceph_buffer_put(ci->i_xattrs.blob);
618                 ci->i_xattrs.blob = xattr_blob;
619                 if (xattr_blob)
620                         memcpy(ci->i_xattrs.blob->vec.iov_base,
621                                iinfo->xattr_data, iinfo->xattr_len);
622                 ci->i_xattrs.version = le64_to_cpu(info->xattr_version);
623                 xattr_blob = NULL;
624         }
625
626         inode->i_mapping->a_ops = &ceph_aops;
627         inode->i_mapping->backing_dev_info =
628                 &ceph_sb_to_client(inode->i_sb)->backing_dev_info;
629
630         switch (inode->i_mode & S_IFMT) {
631         case S_IFIFO:
632         case S_IFBLK:
633         case S_IFCHR:
634         case S_IFSOCK:
635                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
636                 inode->i_op = &ceph_file_iops;
637                 break;
638         case S_IFREG:
639                 inode->i_op = &ceph_file_iops;
640                 inode->i_fop = &ceph_file_fops;
641                 break;
642         case S_IFLNK:
643                 inode->i_op = &ceph_symlink_iops;
644                 if (!ci->i_symlink) {
645                         int symlen = iinfo->symlink_len;
646                         char *sym;
647
648                         BUG_ON(symlen != inode->i_size);
649                         spin_unlock(&inode->i_lock);
650
651                         err = -ENOMEM;
652                         sym = kmalloc(symlen+1, GFP_NOFS);
653                         if (!sym)
654                                 goto out;
655                         memcpy(sym, iinfo->symlink, symlen);
656                         sym[symlen] = 0;
657
658                         spin_lock(&inode->i_lock);
659                         if (!ci->i_symlink)
660                                 ci->i_symlink = sym;
661                         else
662                                 kfree(sym); /* lost a race */
663                 }
664                 break;
665         case S_IFDIR:
666                 inode->i_op = &ceph_dir_iops;
667                 inode->i_fop = &ceph_dir_fops;
668
669                 ci->i_files = le64_to_cpu(info->files);
670                 ci->i_subdirs = le64_to_cpu(info->subdirs);
671                 ci->i_rbytes = le64_to_cpu(info->rbytes);
672                 ci->i_rfiles = le64_to_cpu(info->rfiles);
673                 ci->i_rsubdirs = le64_to_cpu(info->rsubdirs);
674                 ceph_decode_timespec(&ci->i_rctime, &info->rctime);
675
676                 /* set dir completion flag? */
677                 if (ci->i_files == 0 && ci->i_subdirs == 0 &&
678                     ceph_snap(inode) == CEPH_NOSNAP &&
679                     (le32_to_cpu(info->cap.caps) & CEPH_CAP_FILE_SHARED) &&
680                     (issued & CEPH_CAP_FILE_EXCL) == 0 &&
681                     (ci->i_ceph_flags & CEPH_I_COMPLETE) == 0) {
682                         dout(" marking %p complete (empty)\n", inode);
683                         ci->i_ceph_flags |= CEPH_I_COMPLETE;
684                         ci->i_max_offset = 2;
685                 }
686
687                 /* it may be better to set st_size in getattr instead? */
688                 if (ceph_test_opt(ceph_sb_to_client(inode->i_sb), RBYTES))
689                         inode->i_size = ci->i_rbytes;
690                 break;
691         default:
692                 pr_err("fill_inode %llx.%llx BAD mode 0%o\n",
693                        ceph_vinop(inode), inode->i_mode);
694         }
695
696 no_change:
697         spin_unlock(&inode->i_lock);
698
699         /* queue truncate if we saw i_size decrease */
700         if (queue_trunc)
701                 ceph_queue_vmtruncate(inode);
702
703         /* populate frag tree */
704         /* FIXME: move me up, if/when version reflects fragtree changes */
705         nsplits = le32_to_cpu(info->fragtree.nsplits);
706         mutex_lock(&ci->i_fragtree_mutex);
707         for (i = 0; i < nsplits; i++) {
708                 u32 id = le32_to_cpu(info->fragtree.splits[i].frag);
709                 struct ceph_inode_frag *frag = __get_or_create_frag(ci, id);
710
711                 if (IS_ERR(frag))
712                         continue;
713                 frag->split_by = le32_to_cpu(info->fragtree.splits[i].by);
714                 dout(" frag %x split by %d\n", frag->frag, frag->split_by);
715         }
716         mutex_unlock(&ci->i_fragtree_mutex);
717
718         /* were we issued a capability? */
719         if (info->cap.caps) {
720                 if (ceph_snap(inode) == CEPH_NOSNAP) {
721                         ceph_add_cap(inode, session,
722                                      le64_to_cpu(info->cap.cap_id),
723                                      cap_fmode,
724                                      le32_to_cpu(info->cap.caps),
725                                      le32_to_cpu(info->cap.wanted),
726                                      le32_to_cpu(info->cap.seq),
727                                      le32_to_cpu(info->cap.mseq),
728                                      le64_to_cpu(info->cap.realm),
729                                      info->cap.flags,
730                                      caps_reservation);
731                 } else {
732                         spin_lock(&inode->i_lock);
733                         dout(" %p got snap_caps %s\n", inode,
734                              ceph_cap_string(le32_to_cpu(info->cap.caps)));
735                         ci->i_snap_caps |= le32_to_cpu(info->cap.caps);
736                         if (cap_fmode >= 0)
737                                 __ceph_get_fmode(ci, cap_fmode);
738                         spin_unlock(&inode->i_lock);
739                 }
740         } else if (cap_fmode >= 0) {
741                 pr_warning("mds issued no caps on %llx.%llx\n",
742                            ceph_vinop(inode));
743                 __ceph_get_fmode(ci, cap_fmode);
744         }
745
746         /* update delegation info? */
747         if (dirinfo)
748                 ceph_fill_dirfrag(inode, dirinfo);
749
750         err = 0;
751
752 out:
753         if (xattr_blob)
754                 ceph_buffer_put(xattr_blob);
755         return err;
756 }
757
758 /*
759  * caller should hold session s_mutex.
760  */
761 static void update_dentry_lease(struct dentry *dentry,
762                                 struct ceph_mds_reply_lease *lease,
763                                 struct ceph_mds_session *session,
764                                 unsigned long from_time)
765 {
766         struct ceph_dentry_info *di = ceph_dentry(dentry);
767         long unsigned duration = le32_to_cpu(lease->duration_ms);
768         long unsigned ttl = from_time + (duration * HZ) / 1000;
769         long unsigned half_ttl = from_time + (duration * HZ / 2) / 1000;
770         struct inode *dir;
771
772         /* only track leases on regular dentries */
773         if (dentry->d_op != &ceph_dentry_ops)
774                 return;
775
776         spin_lock(&dentry->d_lock);
777         dout("update_dentry_lease %p mask %d duration %lu ms ttl %lu\n",
778              dentry, le16_to_cpu(lease->mask), duration, ttl);
779
780         /* make lease_rdcache_gen match directory */
781         dir = dentry->d_parent->d_inode;
782         di->lease_shared_gen = ceph_inode(dir)->i_shared_gen;
783
784         if (lease->mask == 0)
785                 goto out_unlock;
786
787         if (di->lease_gen == session->s_cap_gen &&
788             time_before(ttl, dentry->d_time))
789                 goto out_unlock;  /* we already have a newer lease. */
790
791         if (di->lease_session && di->lease_session != session)
792                 goto out_unlock;
793
794         ceph_dentry_lru_touch(dentry);
795
796         if (!di->lease_session)
797                 di->lease_session = ceph_get_mds_session(session);
798         di->lease_gen = session->s_cap_gen;
799         di->lease_seq = le32_to_cpu(lease->seq);
800         di->lease_renew_after = half_ttl;
801         di->lease_renew_from = 0;
802         dentry->d_time = ttl;
803 out_unlock:
804         spin_unlock(&dentry->d_lock);
805         return;
806 }
807
808 /*
809  * Set dentry's directory position based on the current dir's max, and
810  * order it in d_subdirs, so that dcache_readdir behaves.
811  */
812 static void ceph_set_dentry_offset(struct dentry *dn)
813 {
814         struct dentry *dir = dn->d_parent;
815         struct inode *inode = dn->d_parent->d_inode;
816         struct ceph_dentry_info *di;
817
818         BUG_ON(!inode);
819
820         di = ceph_dentry(dn);
821
822         spin_lock(&inode->i_lock);
823         if ((ceph_inode(inode)->i_ceph_flags & CEPH_I_COMPLETE) == 0) {
824                 spin_unlock(&inode->i_lock);
825                 return;
826         }
827         di->offset = ceph_inode(inode)->i_max_offset++;
828         spin_unlock(&inode->i_lock);
829
830         spin_lock(&dcache_lock);
831         spin_lock(&dn->d_lock);
832         list_move(&dn->d_u.d_child, &dir->d_subdirs);
833         dout("set_dentry_offset %p %lld (%p %p)\n", dn, di->offset,
834              dn->d_u.d_child.prev, dn->d_u.d_child.next);
835         spin_unlock(&dn->d_lock);
836         spin_unlock(&dcache_lock);
837 }
838
839 /*
840  * splice a dentry to an inode.
841  * caller must hold directory i_mutex for this to be safe.
842  *
843  * we will only rehash the resulting dentry if @prehash is
844  * true; @prehash will be set to false (for the benefit of
845  * the caller) if we fail.
846  */
847 static struct dentry *splice_dentry(struct dentry *dn, struct inode *in,
848                                     bool *prehash)
849 {
850         struct dentry *realdn;
851
852         BUG_ON(dn->d_inode);
853
854         /* dn must be unhashed */
855         if (!d_unhashed(dn))
856                 d_drop(dn);
857         realdn = d_materialise_unique(dn, in);
858         if (IS_ERR(realdn)) {
859                 pr_err("splice_dentry error %ld %p inode %p ino %llx.%llx\n",
860                        PTR_ERR(realdn), dn, in, ceph_vinop(in));
861                 if (prehash)
862                         *prehash = false; /* don't rehash on error */
863                 dn = realdn; /* note realdn contains the error */
864                 goto out;
865         } else if (realdn) {
866                 dout("dn %p (%d) spliced with %p (%d) "
867                      "inode %p ino %llx.%llx\n",
868                      dn, atomic_read(&dn->d_count),
869                      realdn, atomic_read(&realdn->d_count),
870                      realdn->d_inode, ceph_vinop(realdn->d_inode));
871                 dput(dn);
872                 dn = realdn;
873         } else {
874                 BUG_ON(!ceph_dentry(dn));
875                 dout("dn %p attached to %p ino %llx.%llx\n",
876                      dn, dn->d_inode, ceph_vinop(dn->d_inode));
877         }
878         if ((!prehash || *prehash) && d_unhashed(dn))
879                 d_rehash(dn);
880         ceph_set_dentry_offset(dn);
881 out:
882         return dn;
883 }
884
885 /*
886  * Incorporate results into the local cache.  This is either just
887  * one inode, or a directory, dentry, and possibly linked-to inode (e.g.,
888  * after a lookup).
889  *
890  * A reply may contain
891  *         a directory inode along with a dentry.
892  *  and/or a target inode
893  *
894  * Called with snap_rwsem (read).
895  */
896 int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
897                     struct ceph_mds_session *session)
898 {
899         struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
900         struct inode *in = NULL;
901         struct ceph_mds_reply_inode *ininfo;
902         struct ceph_vino vino;
903         struct ceph_client *client = ceph_sb_to_client(sb);
904         int i = 0;
905         int err = 0;
906
907         dout("fill_trace %p is_dentry %d is_target %d\n", req,
908              rinfo->head->is_dentry, rinfo->head->is_target);
909
910 #if 0
911         /*
912          * Debugging hook:
913          *
914          * If we resend completed ops to a recovering mds, we get no
915          * trace.  Since that is very rare, pretend this is the case
916          * to ensure the 'no trace' handlers in the callers behave.
917          *
918          * Fill in inodes unconditionally to avoid breaking cap
919          * invariants.
920          */
921         if (rinfo->head->op & CEPH_MDS_OP_WRITE) {
922                 pr_info("fill_trace faking empty trace on %lld %s\n",
923                         req->r_tid, ceph_mds_op_name(rinfo->head->op));
924                 if (rinfo->head->is_dentry) {
925                         rinfo->head->is_dentry = 0;
926                         err = fill_inode(req->r_locked_dir,
927                                          &rinfo->diri, rinfo->dirfrag,
928                                          session, req->r_request_started, -1);
929                 }
930                 if (rinfo->head->is_target) {
931                         rinfo->head->is_target = 0;
932                         ininfo = rinfo->targeti.in;
933                         vino.ino = le64_to_cpu(ininfo->ino);
934                         vino.snap = le64_to_cpu(ininfo->snapid);
935                         in = ceph_get_inode(sb, vino);
936                         err = fill_inode(in, &rinfo->targeti, NULL,
937                                          session, req->r_request_started,
938                                          req->r_fmode);
939                         iput(in);
940                 }
941         }
942 #endif
943
944         if (!rinfo->head->is_target && !rinfo->head->is_dentry) {
945                 dout("fill_trace reply is empty!\n");
946                 if (rinfo->head->result == 0 && req->r_locked_dir)
947                         ceph_invalidate_dir_request(req);
948                 return 0;
949         }
950
951         if (rinfo->head->is_dentry) {
952                 struct inode *dir = req->r_locked_dir;
953
954                 err = fill_inode(dir, &rinfo->diri, rinfo->dirfrag,
955                                  session, req->r_request_started, -1,
956                                  &req->r_caps_reservation);
957                 if (err < 0)
958                         return err;
959         }
960
961         /*
962          * ignore null lease/binding on snapdir ENOENT, or else we
963          * will have trouble splicing in the virtual snapdir later
964          */
965         if (rinfo->head->is_dentry && !req->r_aborted &&
966             (rinfo->head->is_target || strncmp(req->r_dentry->d_name.name,
967                                                client->mount_args->snapdir_name,
968                                                req->r_dentry->d_name.len))) {
969                 /*
970                  * lookup link rename   : null -> possibly existing inode
971                  * mknod symlink mkdir  : null -> new inode
972                  * unlink               : linked -> null
973                  */
974                 struct inode *dir = req->r_locked_dir;
975                 struct dentry *dn = req->r_dentry;
976                 bool have_dir_cap, have_lease;
977
978                 BUG_ON(!dn);
979                 BUG_ON(!dir);
980                 BUG_ON(dn->d_parent->d_inode != dir);
981                 BUG_ON(ceph_ino(dir) !=
982                        le64_to_cpu(rinfo->diri.in->ino));
983                 BUG_ON(ceph_snap(dir) !=
984                        le64_to_cpu(rinfo->diri.in->snapid));
985
986                 /* do we have a lease on the whole dir? */
987                 have_dir_cap =
988                         (le32_to_cpu(rinfo->diri.in->cap.caps) &
989                          CEPH_CAP_FILE_SHARED);
990
991                 /* do we have a dn lease? */
992                 have_lease = have_dir_cap ||
993                         (le16_to_cpu(rinfo->dlease->mask) &
994                          CEPH_LOCK_DN);
995
996                 if (!have_lease)
997                         dout("fill_trace  no dentry lease or dir cap\n");
998
999                 /* rename? */
1000                 if (req->r_old_dentry && req->r_op == CEPH_MDS_OP_RENAME) {
1001                         dout(" src %p '%.*s' dst %p '%.*s'\n",
1002                              req->r_old_dentry,
1003                              req->r_old_dentry->d_name.len,
1004                              req->r_old_dentry->d_name.name,
1005                              dn, dn->d_name.len, dn->d_name.name);
1006                         dout("fill_trace doing d_move %p -> %p\n",
1007                              req->r_old_dentry, dn);
1008
1009                         /* d_move screws up d_subdirs order */
1010                         ceph_i_clear(dir, CEPH_I_COMPLETE);
1011
1012                         d_move(req->r_old_dentry, dn);
1013                         dout(" src %p '%.*s' dst %p '%.*s'\n",
1014                              req->r_old_dentry,
1015                              req->r_old_dentry->d_name.len,
1016                              req->r_old_dentry->d_name.name,
1017                              dn, dn->d_name.len, dn->d_name.name);
1018
1019                         /* ensure target dentry is invalidated, despite
1020                            rehashing bug in vfs_rename_dir */
1021                         ceph_invalidate_dentry_lease(dn);
1022
1023                         /* take overwritten dentry's readdir offset */
1024                         dout("dn %p gets %p offset %lld (old offset %lld)\n",
1025                              req->r_old_dentry, dn, ceph_dentry(dn)->offset,
1026                              ceph_dentry(req->r_old_dentry)->offset);
1027                         ceph_dentry(req->r_old_dentry)->offset =
1028                                 ceph_dentry(dn)->offset;
1029
1030                         dn = req->r_old_dentry;  /* use old_dentry */
1031                         in = dn->d_inode;
1032                 }
1033
1034                 /* null dentry? */
1035                 if (!rinfo->head->is_target) {
1036                         dout("fill_trace null dentry\n");
1037                         if (dn->d_inode) {
1038                                 dout("d_delete %p\n", dn);
1039                                 d_delete(dn);
1040                         } else {
1041                                 dout("d_instantiate %p NULL\n", dn);
1042                                 d_instantiate(dn, NULL);
1043                                 if (have_lease && d_unhashed(dn))
1044                                         d_rehash(dn);
1045                                 update_dentry_lease(dn, rinfo->dlease,
1046                                                     session,
1047                                                     req->r_request_started);
1048                         }
1049                         goto done;
1050                 }
1051
1052                 /* attach proper inode */
1053                 ininfo = rinfo->targeti.in;
1054                 vino.ino = le64_to_cpu(ininfo->ino);
1055                 vino.snap = le64_to_cpu(ininfo->snapid);
1056                 if (!dn->d_inode) {
1057                         in = ceph_get_inode(sb, vino);
1058                         if (IS_ERR(in)) {
1059                                 pr_err("fill_trace bad get_inode "
1060                                        "%llx.%llx\n", vino.ino, vino.snap);
1061                                 err = PTR_ERR(in);
1062                                 d_delete(dn);
1063                                 goto done;
1064                         }
1065                         dn = splice_dentry(dn, in, &have_lease);
1066                         if (IS_ERR(dn)) {
1067                                 err = PTR_ERR(dn);
1068                                 goto done;
1069                         }
1070                         req->r_dentry = dn;  /* may have spliced */
1071                         igrab(in);
1072                 } else if (ceph_ino(in) == vino.ino &&
1073                            ceph_snap(in) == vino.snap) {
1074                         igrab(in);
1075                 } else {
1076                         dout(" %p links to %p %llx.%llx, not %llx.%llx\n",
1077                              dn, in, ceph_ino(in), ceph_snap(in),
1078                              vino.ino, vino.snap);
1079                         have_lease = false;
1080                         in = NULL;
1081                 }
1082
1083                 if (have_lease)
1084                         update_dentry_lease(dn, rinfo->dlease, session,
1085                                             req->r_request_started);
1086                 dout(" final dn %p\n", dn);
1087                 i++;
1088         } else if (req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
1089                    req->r_op == CEPH_MDS_OP_MKSNAP) {
1090                 struct dentry *dn = req->r_dentry;
1091
1092                 /* fill out a snapdir LOOKUPSNAP dentry */
1093                 BUG_ON(!dn);
1094                 BUG_ON(!req->r_locked_dir);
1095                 BUG_ON(ceph_snap(req->r_locked_dir) != CEPH_SNAPDIR);
1096                 ininfo = rinfo->targeti.in;
1097                 vino.ino = le64_to_cpu(ininfo->ino);
1098                 vino.snap = le64_to_cpu(ininfo->snapid);
1099                 in = ceph_get_inode(sb, vino);
1100                 if (IS_ERR(in)) {
1101                         pr_err("fill_inode get_inode badness %llx.%llx\n",
1102                                vino.ino, vino.snap);
1103                         err = PTR_ERR(in);
1104                         d_delete(dn);
1105                         goto done;
1106                 }
1107                 dout(" linking snapped dir %p to dn %p\n", in, dn);
1108                 dn = splice_dentry(dn, in, NULL);
1109                 if (IS_ERR(dn)) {
1110                         err = PTR_ERR(dn);
1111                         goto done;
1112                 }
1113                 req->r_dentry = dn;  /* may have spliced */
1114                 igrab(in);
1115                 rinfo->head->is_dentry = 1;  /* fool notrace handlers */
1116         }
1117
1118         if (rinfo->head->is_target) {
1119                 vino.ino = le64_to_cpu(rinfo->targeti.in->ino);
1120                 vino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
1121
1122                 if (in == NULL || ceph_ino(in) != vino.ino ||
1123                     ceph_snap(in) != vino.snap) {
1124                         in = ceph_get_inode(sb, vino);
1125                         if (IS_ERR(in)) {
1126                                 err = PTR_ERR(in);
1127                                 goto done;
1128                         }
1129                 }
1130                 req->r_target_inode = in;
1131
1132                 err = fill_inode(in,
1133                                  &rinfo->targeti, NULL,
1134                                  session, req->r_request_started,
1135                                  (le32_to_cpu(rinfo->head->result) == 0) ?
1136                                  req->r_fmode : -1,
1137                                  &req->r_caps_reservation);
1138                 if (err < 0) {
1139                         pr_err("fill_inode badness %p %llx.%llx\n",
1140                                in, ceph_vinop(in));
1141                         goto done;
1142                 }
1143         }
1144
1145 done:
1146         dout("fill_trace done err=%d\n", err);
1147         return err;
1148 }
1149
1150 /*
1151  * Prepopulate our cache with readdir results, leases, etc.
1152  */
1153 int ceph_readdir_prepopulate(struct ceph_mds_request *req,
1154                              struct ceph_mds_session *session)
1155 {
1156         struct dentry *parent = req->r_dentry;
1157         struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1158         struct qstr dname;
1159         struct dentry *dn;
1160         struct inode *in;
1161         int err = 0, i;
1162         struct inode *snapdir = NULL;
1163         struct ceph_mds_request_head *rhead = req->r_request->front.iov_base;
1164         u64 frag = le32_to_cpu(rhead->args.readdir.frag);
1165         struct ceph_dentry_info *di;
1166
1167         if (le32_to_cpu(rinfo->head->op) == CEPH_MDS_OP_LSSNAP) {
1168                 snapdir = ceph_get_snapdir(parent->d_inode);
1169                 parent = d_find_alias(snapdir);
1170                 dout("readdir_prepopulate %d items under SNAPDIR dn %p\n",
1171                      rinfo->dir_nr, parent);
1172         } else {
1173                 dout("readdir_prepopulate %d items under dn %p\n",
1174                      rinfo->dir_nr, parent);
1175                 if (rinfo->dir_dir)
1176                         ceph_fill_dirfrag(parent->d_inode, rinfo->dir_dir);
1177         }
1178
1179         for (i = 0; i < rinfo->dir_nr; i++) {
1180                 struct ceph_vino vino;
1181
1182                 dname.name = rinfo->dir_dname[i];
1183                 dname.len = rinfo->dir_dname_len[i];
1184                 dname.hash = full_name_hash(dname.name, dname.len);
1185
1186                 vino.ino = le64_to_cpu(rinfo->dir_in[i].in->ino);
1187                 vino.snap = le64_to_cpu(rinfo->dir_in[i].in->snapid);
1188
1189 retry_lookup:
1190                 dn = d_lookup(parent, &dname);
1191                 dout("d_lookup on parent=%p name=%.*s got %p\n",
1192                      parent, dname.len, dname.name, dn);
1193
1194                 if (!dn) {
1195                         dn = d_alloc(parent, &dname);
1196                         dout("d_alloc %p '%.*s' = %p\n", parent,
1197                              dname.len, dname.name, dn);
1198                         if (dn == NULL) {
1199                                 dout("d_alloc badness\n");
1200                                 err = -ENOMEM;
1201                                 goto out;
1202                         }
1203                         err = ceph_init_dentry(dn);
1204                         if (err < 0) {
1205                                 dput(dn);
1206                                 goto out;
1207                         }
1208                 } else if (dn->d_inode &&
1209                            (ceph_ino(dn->d_inode) != vino.ino ||
1210                             ceph_snap(dn->d_inode) != vino.snap)) {
1211                         dout(" dn %p points to wrong inode %p\n",
1212                              dn, dn->d_inode);
1213                         d_delete(dn);
1214                         dput(dn);
1215                         goto retry_lookup;
1216                 } else {
1217                         /* reorder parent's d_subdirs */
1218                         spin_lock(&dcache_lock);
1219                         spin_lock(&dn->d_lock);
1220                         list_move(&dn->d_u.d_child, &parent->d_subdirs);
1221                         spin_unlock(&dn->d_lock);
1222                         spin_unlock(&dcache_lock);
1223                 }
1224
1225                 di = dn->d_fsdata;
1226                 di->offset = ceph_make_fpos(frag, i + req->r_readdir_offset);
1227
1228                 /* inode */
1229                 if (dn->d_inode) {
1230                         in = dn->d_inode;
1231                 } else {
1232                         in = ceph_get_inode(parent->d_sb, vino);
1233                         if (IS_ERR(in)) {
1234                                 dout("new_inode badness\n");
1235                                 d_delete(dn);
1236                                 dput(dn);
1237                                 err = PTR_ERR(in);
1238                                 goto out;
1239                         }
1240                         dn = splice_dentry(dn, in, NULL);
1241                         if (IS_ERR(dn))
1242                                 dn = NULL;
1243                 }
1244
1245                 if (fill_inode(in, &rinfo->dir_in[i], NULL, session,
1246                                req->r_request_started, -1,
1247                                &req->r_caps_reservation) < 0) {
1248                         pr_err("fill_inode badness on %p\n", in);
1249                         goto next_item;
1250                 }
1251                 if (dn)
1252                         update_dentry_lease(dn, rinfo->dir_dlease[i],
1253                                             req->r_session,
1254                                             req->r_request_started);
1255 next_item:
1256                 if (dn)
1257                         dput(dn);
1258         }
1259         req->r_did_prepopulate = true;
1260
1261 out:
1262         if (snapdir) {
1263                 iput(snapdir);
1264                 dput(parent);
1265         }
1266         dout("readdir_prepopulate done\n");
1267         return err;
1268 }
1269
1270 int ceph_inode_set_size(struct inode *inode, loff_t size)
1271 {
1272         struct ceph_inode_info *ci = ceph_inode(inode);
1273         int ret = 0;
1274
1275         spin_lock(&inode->i_lock);
1276         dout("set_size %p %llu -> %llu\n", inode, inode->i_size, size);
1277         inode->i_size = size;
1278         inode->i_blocks = (size + (1 << 9) - 1) >> 9;
1279
1280         /* tell the MDS if we are approaching max_size */
1281         if ((size << 1) >= ci->i_max_size &&
1282             (ci->i_reported_size << 1) < ci->i_max_size)
1283                 ret = 1;
1284
1285         spin_unlock(&inode->i_lock);
1286         return ret;
1287 }
1288
1289 /*
1290  * Write back inode data in a worker thread.  (This can't be done
1291  * in the message handler context.)
1292  */
1293 void ceph_queue_writeback(struct inode *inode)
1294 {
1295         if (queue_work(ceph_inode_to_client(inode)->wb_wq,
1296                        &ceph_inode(inode)->i_wb_work)) {
1297                 dout("ceph_queue_writeback %p\n", inode);
1298                 igrab(inode);
1299         } else {
1300                 dout("ceph_queue_writeback %p failed\n", inode);
1301         }
1302 }
1303
1304 static void ceph_writeback_work(struct work_struct *work)
1305 {
1306         struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
1307                                                   i_wb_work);
1308         struct inode *inode = &ci->vfs_inode;
1309
1310         dout("writeback %p\n", inode);
1311         filemap_fdatawrite(&inode->i_data);
1312         iput(inode);
1313 }
1314
1315 /*
1316  * queue an async invalidation
1317  */
1318 void ceph_queue_invalidate(struct inode *inode)
1319 {
1320         if (queue_work(ceph_inode_to_client(inode)->pg_inv_wq,
1321                        &ceph_inode(inode)->i_pg_inv_work)) {
1322                 dout("ceph_queue_invalidate %p\n", inode);
1323                 igrab(inode);
1324         } else {
1325                 dout("ceph_queue_invalidate %p failed\n", inode);
1326         }
1327 }
1328
1329 /*
1330  * invalidate any pages that are not dirty or under writeback.  this
1331  * includes pages that are clean and mapped.
1332  */
1333 static void ceph_invalidate_nondirty_pages(struct address_space *mapping)
1334 {
1335         struct pagevec pvec;
1336         pgoff_t next = 0;
1337         int i;
1338
1339         pagevec_init(&pvec, 0);
1340         while (pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
1341                 for (i = 0; i < pagevec_count(&pvec); i++) {
1342                         struct page *page = pvec.pages[i];
1343                         pgoff_t index;
1344                         int skip_page =
1345                                 (PageDirty(page) || PageWriteback(page));
1346
1347                         if (!skip_page)
1348                                 skip_page = !trylock_page(page);
1349
1350                         /*
1351                          * We really shouldn't be looking at the ->index of an
1352                          * unlocked page.  But we're not allowed to lock these
1353                          * pages.  So we rely upon nobody altering the ->index
1354                          * of this (pinned-by-us) page.
1355                          */
1356                         index = page->index;
1357                         if (index > next)
1358                                 next = index;
1359                         next++;
1360
1361                         if (skip_page)
1362                                 continue;
1363
1364                         generic_error_remove_page(mapping, page);
1365                         unlock_page(page);
1366                 }
1367                 pagevec_release(&pvec);
1368                 cond_resched();
1369         }
1370 }
1371
1372 /*
1373  * Invalidate inode pages in a worker thread.  (This can't be done
1374  * in the message handler context.)
1375  */
1376 static void ceph_invalidate_work(struct work_struct *work)
1377 {
1378         struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
1379                                                   i_pg_inv_work);
1380         struct inode *inode = &ci->vfs_inode;
1381         u32 orig_gen;
1382         int check = 0;
1383
1384         spin_lock(&inode->i_lock);
1385         dout("invalidate_pages %p gen %d revoking %d\n", inode,
1386              ci->i_rdcache_gen, ci->i_rdcache_revoking);
1387         if (ci->i_rdcache_gen == 0 ||
1388             ci->i_rdcache_revoking != ci->i_rdcache_gen) {
1389                 BUG_ON(ci->i_rdcache_revoking > ci->i_rdcache_gen);
1390                 /* nevermind! */
1391                 ci->i_rdcache_revoking = 0;
1392                 spin_unlock(&inode->i_lock);
1393                 goto out;
1394         }
1395         orig_gen = ci->i_rdcache_gen;
1396         spin_unlock(&inode->i_lock);
1397
1398         ceph_invalidate_nondirty_pages(inode->i_mapping);
1399
1400         spin_lock(&inode->i_lock);
1401         if (orig_gen == ci->i_rdcache_gen) {
1402                 dout("invalidate_pages %p gen %d successful\n", inode,
1403                      ci->i_rdcache_gen);
1404                 ci->i_rdcache_gen = 0;
1405                 ci->i_rdcache_revoking = 0;
1406                 check = 1;
1407         } else {
1408                 dout("invalidate_pages %p gen %d raced, gen now %d\n",
1409                      inode, orig_gen, ci->i_rdcache_gen);
1410         }
1411         spin_unlock(&inode->i_lock);
1412
1413         if (check)
1414                 ceph_check_caps(ci, 0, NULL);
1415 out:
1416         iput(inode);
1417 }
1418
1419
1420 /*
1421  * called by trunc_wq; take i_mutex ourselves
1422  *
1423  * We also truncate in a separate thread as well.
1424  */
1425 static void ceph_vmtruncate_work(struct work_struct *work)
1426 {
1427         struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
1428                                                   i_vmtruncate_work);
1429         struct inode *inode = &ci->vfs_inode;
1430
1431         dout("vmtruncate_work %p\n", inode);
1432         mutex_lock(&inode->i_mutex);
1433         __ceph_do_pending_vmtruncate(inode);
1434         mutex_unlock(&inode->i_mutex);
1435         iput(inode);
1436 }
1437
1438 /*
1439  * Queue an async vmtruncate.  If we fail to queue work, we will handle
1440  * the truncation the next time we call __ceph_do_pending_vmtruncate.
1441  */
1442 void ceph_queue_vmtruncate(struct inode *inode)
1443 {
1444         struct ceph_inode_info *ci = ceph_inode(inode);
1445
1446         if (queue_work(ceph_sb_to_client(inode->i_sb)->trunc_wq,
1447                        &ci->i_vmtruncate_work)) {
1448                 dout("ceph_queue_vmtruncate %p\n", inode);
1449                 igrab(inode);
1450         } else {
1451                 dout("ceph_queue_vmtruncate %p failed, pending=%d\n",
1452                      inode, ci->i_truncate_pending);
1453         }
1454 }
1455
1456 /*
1457  * called with i_mutex held.
1458  *
1459  * Make sure any pending truncation is applied before doing anything
1460  * that may depend on it.
1461  */
1462 void __ceph_do_pending_vmtruncate(struct inode *inode)
1463 {
1464         struct ceph_inode_info *ci = ceph_inode(inode);
1465         u64 to;
1466         int wrbuffer_refs, wake = 0;
1467
1468 retry:
1469         spin_lock(&inode->i_lock);
1470         if (ci->i_truncate_pending == 0) {
1471                 dout("__do_pending_vmtruncate %p none pending\n", inode);
1472                 spin_unlock(&inode->i_lock);
1473                 return;
1474         }
1475
1476         /*
1477          * make sure any dirty snapped pages are flushed before we
1478          * possibly truncate them.. so write AND block!
1479          */
1480         if (ci->i_wrbuffer_ref_head < ci->i_wrbuffer_ref) {
1481                 dout("__do_pending_vmtruncate %p flushing snaps first\n",
1482                      inode);
1483                 spin_unlock(&inode->i_lock);
1484                 filemap_write_and_wait_range(&inode->i_data, 0,
1485                                              inode->i_sb->s_maxbytes);
1486                 goto retry;
1487         }
1488
1489         to = ci->i_truncate_size;
1490         wrbuffer_refs = ci->i_wrbuffer_ref;
1491         dout("__do_pending_vmtruncate %p (%d) to %lld\n", inode,
1492              ci->i_truncate_pending, to);
1493         spin_unlock(&inode->i_lock);
1494
1495         truncate_inode_pages(inode->i_mapping, to);
1496
1497         spin_lock(&inode->i_lock);
1498         ci->i_truncate_pending--;
1499         if (ci->i_truncate_pending == 0)
1500                 wake = 1;
1501         spin_unlock(&inode->i_lock);
1502
1503         if (wrbuffer_refs == 0)
1504                 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
1505         if (wake)
1506                 wake_up_all(&ci->i_cap_wq);
1507 }
1508
1509
1510 /*
1511  * symlinks
1512  */
1513 static void *ceph_sym_follow_link(struct dentry *dentry, struct nameidata *nd)
1514 {
1515         struct ceph_inode_info *ci = ceph_inode(dentry->d_inode);
1516         nd_set_link(nd, ci->i_symlink);
1517         return NULL;
1518 }
1519
1520 static const struct inode_operations ceph_symlink_iops = {
1521         .readlink = generic_readlink,
1522         .follow_link = ceph_sym_follow_link,
1523 };
1524
1525 /*
1526  * setattr
1527  */
1528 int ceph_setattr(struct dentry *dentry, struct iattr *attr)
1529 {
1530         struct inode *inode = dentry->d_inode;
1531         struct ceph_inode_info *ci = ceph_inode(inode);
1532         struct inode *parent_inode = dentry->d_parent->d_inode;
1533         const unsigned int ia_valid = attr->ia_valid;
1534         struct ceph_mds_request *req;
1535         struct ceph_mds_client *mdsc = &ceph_sb_to_client(dentry->d_sb)->mdsc;
1536         int issued;
1537         int release = 0, dirtied = 0;
1538         int mask = 0;
1539         int err = 0;
1540
1541         if (ceph_snap(inode) != CEPH_NOSNAP)
1542                 return -EROFS;
1543
1544         __ceph_do_pending_vmtruncate(inode);
1545
1546         err = inode_change_ok(inode, attr);
1547         if (err != 0)
1548                 return err;
1549
1550         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETATTR,
1551                                        USE_AUTH_MDS);
1552         if (IS_ERR(req))
1553                 return PTR_ERR(req);
1554
1555         spin_lock(&inode->i_lock);
1556         issued = __ceph_caps_issued(ci, NULL);
1557         dout("setattr %p issued %s\n", inode, ceph_cap_string(issued));
1558
1559         if (ia_valid & ATTR_UID) {
1560                 dout("setattr %p uid %d -> %d\n", inode,
1561                      inode->i_uid, attr->ia_uid);
1562                 if (issued & CEPH_CAP_AUTH_EXCL) {
1563                         inode->i_uid = attr->ia_uid;
1564                         dirtied |= CEPH_CAP_AUTH_EXCL;
1565                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
1566                            attr->ia_uid != inode->i_uid) {
1567                         req->r_args.setattr.uid = cpu_to_le32(attr->ia_uid);
1568                         mask |= CEPH_SETATTR_UID;
1569                         release |= CEPH_CAP_AUTH_SHARED;
1570                 }
1571         }
1572         if (ia_valid & ATTR_GID) {
1573                 dout("setattr %p gid %d -> %d\n", inode,
1574                      inode->i_gid, attr->ia_gid);
1575                 if (issued & CEPH_CAP_AUTH_EXCL) {
1576                         inode->i_gid = attr->ia_gid;
1577                         dirtied |= CEPH_CAP_AUTH_EXCL;
1578                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
1579                            attr->ia_gid != inode->i_gid) {
1580                         req->r_args.setattr.gid = cpu_to_le32(attr->ia_gid);
1581                         mask |= CEPH_SETATTR_GID;
1582                         release |= CEPH_CAP_AUTH_SHARED;
1583                 }
1584         }
1585         if (ia_valid & ATTR_MODE) {
1586                 dout("setattr %p mode 0%o -> 0%o\n", inode, inode->i_mode,
1587                      attr->ia_mode);
1588                 if (issued & CEPH_CAP_AUTH_EXCL) {
1589                         inode->i_mode = attr->ia_mode;
1590                         dirtied |= CEPH_CAP_AUTH_EXCL;
1591                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
1592                            attr->ia_mode != inode->i_mode) {
1593                         req->r_args.setattr.mode = cpu_to_le32(attr->ia_mode);
1594                         mask |= CEPH_SETATTR_MODE;
1595                         release |= CEPH_CAP_AUTH_SHARED;
1596                 }
1597         }
1598
1599         if (ia_valid & ATTR_ATIME) {
1600                 dout("setattr %p atime %ld.%ld -> %ld.%ld\n", inode,
1601                      inode->i_atime.tv_sec, inode->i_atime.tv_nsec,
1602                      attr->ia_atime.tv_sec, attr->ia_atime.tv_nsec);
1603                 if (issued & CEPH_CAP_FILE_EXCL) {
1604                         ci->i_time_warp_seq++;
1605                         inode->i_atime = attr->ia_atime;
1606                         dirtied |= CEPH_CAP_FILE_EXCL;
1607                 } else if ((issued & CEPH_CAP_FILE_WR) &&
1608                            timespec_compare(&inode->i_atime,
1609                                             &attr->ia_atime) < 0) {
1610                         inode->i_atime = attr->ia_atime;
1611                         dirtied |= CEPH_CAP_FILE_WR;
1612                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
1613                            !timespec_equal(&inode->i_atime, &attr->ia_atime)) {
1614                         ceph_encode_timespec(&req->r_args.setattr.atime,
1615                                              &attr->ia_atime);
1616                         mask |= CEPH_SETATTR_ATIME;
1617                         release |= CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_RD |
1618                                 CEPH_CAP_FILE_WR;
1619                 }
1620         }
1621         if (ia_valid & ATTR_MTIME) {
1622                 dout("setattr %p mtime %ld.%ld -> %ld.%ld\n", inode,
1623                      inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
1624                      attr->ia_mtime.tv_sec, attr->ia_mtime.tv_nsec);
1625                 if (issued & CEPH_CAP_FILE_EXCL) {
1626                         ci->i_time_warp_seq++;
1627                         inode->i_mtime = attr->ia_mtime;
1628                         dirtied |= CEPH_CAP_FILE_EXCL;
1629                 } else if ((issued & CEPH_CAP_FILE_WR) &&
1630                            timespec_compare(&inode->i_mtime,
1631                                             &attr->ia_mtime) < 0) {
1632                         inode->i_mtime = attr->ia_mtime;
1633                         dirtied |= CEPH_CAP_FILE_WR;
1634                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
1635                            !timespec_equal(&inode->i_mtime, &attr->ia_mtime)) {
1636                         ceph_encode_timespec(&req->r_args.setattr.mtime,
1637                                              &attr->ia_mtime);
1638                         mask |= CEPH_SETATTR_MTIME;
1639                         release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
1640                                 CEPH_CAP_FILE_WR;
1641                 }
1642         }
1643         if (ia_valid & ATTR_SIZE) {
1644                 dout("setattr %p size %lld -> %lld\n", inode,
1645                      inode->i_size, attr->ia_size);
1646                 if (attr->ia_size > inode->i_sb->s_maxbytes) {
1647                         err = -EINVAL;
1648                         goto out;
1649                 }
1650                 if ((issued & CEPH_CAP_FILE_EXCL) &&
1651                     attr->ia_size > inode->i_size) {
1652                         inode->i_size = attr->ia_size;
1653                         inode->i_blocks =
1654                                 (attr->ia_size + (1 << 9) - 1) >> 9;
1655                         inode->i_ctime = attr->ia_ctime;
1656                         ci->i_reported_size = attr->ia_size;
1657                         dirtied |= CEPH_CAP_FILE_EXCL;
1658                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
1659                            attr->ia_size != inode->i_size) {
1660                         req->r_args.setattr.size = cpu_to_le64(attr->ia_size);
1661                         req->r_args.setattr.old_size =
1662                                 cpu_to_le64(inode->i_size);
1663                         mask |= CEPH_SETATTR_SIZE;
1664                         release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
1665                                 CEPH_CAP_FILE_WR;
1666                 }
1667         }
1668
1669         /* these do nothing */
1670         if (ia_valid & ATTR_CTIME) {
1671                 bool only = (ia_valid & (ATTR_SIZE|ATTR_MTIME|ATTR_ATIME|
1672                                          ATTR_MODE|ATTR_UID|ATTR_GID)) == 0;
1673                 dout("setattr %p ctime %ld.%ld -> %ld.%ld (%s)\n", inode,
1674                      inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
1675                      attr->ia_ctime.tv_sec, attr->ia_ctime.tv_nsec,
1676                      only ? "ctime only" : "ignored");
1677                 inode->i_ctime = attr->ia_ctime;
1678                 if (only) {
1679                         /*
1680                          * if kernel wants to dirty ctime but nothing else,
1681                          * we need to choose a cap to dirty under, or do
1682                          * a almost-no-op setattr
1683                          */
1684                         if (issued & CEPH_CAP_AUTH_EXCL)
1685                                 dirtied |= CEPH_CAP_AUTH_EXCL;
1686                         else if (issued & CEPH_CAP_FILE_EXCL)
1687                                 dirtied |= CEPH_CAP_FILE_EXCL;
1688                         else if (issued & CEPH_CAP_XATTR_EXCL)
1689                                 dirtied |= CEPH_CAP_XATTR_EXCL;
1690                         else
1691                                 mask |= CEPH_SETATTR_CTIME;
1692                 }
1693         }
1694         if (ia_valid & ATTR_FILE)
1695                 dout("setattr %p ATTR_FILE ... hrm!\n", inode);
1696
1697         if (dirtied) {
1698                 __ceph_mark_dirty_caps(ci, dirtied);
1699                 inode->i_ctime = CURRENT_TIME;
1700         }
1701
1702         release &= issued;
1703         spin_unlock(&inode->i_lock);
1704
1705         if (mask) {
1706                 req->r_inode = igrab(inode);
1707                 req->r_inode_drop = release;
1708                 req->r_args.setattr.mask = cpu_to_le32(mask);
1709                 req->r_num_caps = 1;
1710                 err = ceph_mdsc_do_request(mdsc, parent_inode, req);
1711         }
1712         dout("setattr %p result=%d (%s locally, %d remote)\n", inode, err,
1713              ceph_cap_string(dirtied), mask);
1714
1715         ceph_mdsc_put_request(req);
1716         __ceph_do_pending_vmtruncate(inode);
1717         return err;
1718 out:
1719         spin_unlock(&inode->i_lock);
1720         ceph_mdsc_put_request(req);
1721         return err;
1722 }
1723
1724 /*
1725  * Verify that we have a lease on the given mask.  If not,
1726  * do a getattr against an mds.
1727  */
1728 int ceph_do_getattr(struct inode *inode, int mask)
1729 {
1730         struct ceph_client *client = ceph_sb_to_client(inode->i_sb);
1731         struct ceph_mds_client *mdsc = &client->mdsc;
1732         struct ceph_mds_request *req;
1733         int err;
1734
1735         if (ceph_snap(inode) == CEPH_SNAPDIR) {
1736                 dout("do_getattr inode %p SNAPDIR\n", inode);
1737                 return 0;
1738         }
1739
1740         dout("do_getattr inode %p mask %s\n", inode, ceph_cap_string(mask));
1741         if (ceph_caps_issued_mask(ceph_inode(inode), mask, 1))
1742                 return 0;
1743
1744         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
1745         if (IS_ERR(req))
1746                 return PTR_ERR(req);
1747         req->r_inode = igrab(inode);
1748         req->r_num_caps = 1;
1749         req->r_args.getattr.mask = cpu_to_le32(mask);
1750         err = ceph_mdsc_do_request(mdsc, NULL, req);
1751         ceph_mdsc_put_request(req);
1752         dout("do_getattr result=%d\n", err);
1753         return err;
1754 }
1755
1756
1757 /*
1758  * Check inode permissions.  We verify we have a valid value for
1759  * the AUTH cap, then call the generic handler.
1760  */
1761 int ceph_permission(struct inode *inode, int mask)
1762 {
1763         int err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED);
1764
1765         if (!err)
1766                 err = generic_permission(inode, mask, NULL);
1767         return err;
1768 }
1769
1770 /*
1771  * Get all attributes.  Hopefully somedata we'll have a statlite()
1772  * and can limit the fields we require to be accurate.
1773  */
1774 int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
1775                  struct kstat *stat)
1776 {
1777         struct inode *inode = dentry->d_inode;
1778         struct ceph_inode_info *ci = ceph_inode(inode);
1779         int err;
1780
1781         err = ceph_do_getattr(inode, CEPH_STAT_CAP_INODE_ALL);
1782         if (!err) {
1783                 generic_fillattr(inode, stat);
1784                 stat->ino = inode->i_ino;
1785                 if (ceph_snap(inode) != CEPH_NOSNAP)
1786                         stat->dev = ceph_snap(inode);
1787                 else
1788                         stat->dev = 0;
1789                 if (S_ISDIR(inode->i_mode)) {
1790                         stat->size = ci->i_rbytes;
1791                         stat->blocks = 0;
1792                         stat->blksize = 65536;
1793                 }
1794         }
1795         return err;
1796 }