Version:  2.0.40 2.2.26 2.4.37 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0

Linux/fs/nfs/inode.c

  1 /*
  2  *  linux/fs/nfs/inode.c
  3  *
  4  *  Copyright (C) 1992  Rick Sladkey
  5  *
  6  *  nfs inode and superblock handling functions
  7  *
  8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
  9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
 10  *
 11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
 12  *  J.S.Peatfield@damtp.cam.ac.uk
 13  *
 14  */
 15 
 16 #include <linux/module.h>
 17 #include <linux/init.h>
 18 #include <linux/sched.h>
 19 #include <linux/time.h>
 20 #include <linux/kernel.h>
 21 #include <linux/mm.h>
 22 #include <linux/string.h>
 23 #include <linux/stat.h>
 24 #include <linux/errno.h>
 25 #include <linux/unistd.h>
 26 #include <linux/sunrpc/clnt.h>
 27 #include <linux/sunrpc/stats.h>
 28 #include <linux/sunrpc/metrics.h>
 29 #include <linux/nfs_fs.h>
 30 #include <linux/nfs_mount.h>
 31 #include <linux/nfs4_mount.h>
 32 #include <linux/lockd/bind.h>
 33 #include <linux/seq_file.h>
 34 #include <linux/mount.h>
 35 #include <linux/vfs.h>
 36 #include <linux/inet.h>
 37 #include <linux/nfs_xdr.h>
 38 #include <linux/slab.h>
 39 #include <linux/compat.h>
 40 #include <linux/freezer.h>
 41 
 42 #include <asm/uaccess.h>
 43 
 44 #include "nfs4_fs.h"
 45 #include "callback.h"
 46 #include "delegation.h"
 47 #include "iostat.h"
 48 #include "internal.h"
 49 #include "fscache.h"
 50 #include "pnfs.h"
 51 #include "nfs.h"
 52 #include "netns.h"
 53 
 54 #include "nfstrace.h"
 55 
 56 #define NFSDBG_FACILITY         NFSDBG_VFS
 57 
 58 #define NFS_64_BIT_INODE_NUMBERS_ENABLED        1
 59 
 60 /* Default is to see 64-bit inode numbers */
 61 static bool enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
 62 
 63 static void nfs_invalidate_inode(struct inode *);
 64 static int nfs_update_inode(struct inode *, struct nfs_fattr *);
 65 
 66 static struct kmem_cache * nfs_inode_cachep;
 67 
 68 static inline unsigned long
 69 nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
 70 {
 71         return nfs_fileid_to_ino_t(fattr->fileid);
 72 }
 73 
 74 /**
 75  * nfs_wait_bit_killable - helper for functions that are sleeping on bit locks
 76  * @word: long word containing the bit lock
 77  */
 78 int nfs_wait_bit_killable(struct wait_bit_key *key)
 79 {
 80         if (fatal_signal_pending(current))
 81                 return -ERESTARTSYS;
 82         freezable_schedule_unsafe();
 83         return 0;
 84 }
 85 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
 86 
 87 /**
 88  * nfs_compat_user_ino64 - returns the user-visible inode number
 89  * @fileid: 64-bit fileid
 90  *
 91  * This function returns a 32-bit inode number if the boot parameter
 92  * nfs.enable_ino64 is zero.
 93  */
 94 u64 nfs_compat_user_ino64(u64 fileid)
 95 {
 96 #ifdef CONFIG_COMPAT
 97         compat_ulong_t ino;
 98 #else   
 99         unsigned long ino;
100 #endif
101 
102         if (enable_ino64)
103                 return fileid;
104         ino = fileid;
105         if (sizeof(ino) < sizeof(fileid))
106                 ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
107         return ino;
108 }
109 
110 int nfs_drop_inode(struct inode *inode)
111 {
112         return NFS_STALE(inode) || generic_drop_inode(inode);
113 }
114 EXPORT_SYMBOL_GPL(nfs_drop_inode);
115 
116 void nfs_clear_inode(struct inode *inode)
117 {
118         /*
119          * The following should never happen...
120          */
121         WARN_ON_ONCE(nfs_have_writebacks(inode));
122         WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
123         nfs_zap_acl_cache(inode);
124         nfs_access_zap_cache(inode);
125         nfs_fscache_clear_inode(inode);
126 }
127 EXPORT_SYMBOL_GPL(nfs_clear_inode);
128 
129 void nfs_evict_inode(struct inode *inode)
130 {
131         truncate_inode_pages_final(&inode->i_data);
132         clear_inode(inode);
133         nfs_clear_inode(inode);
134 }
135 
136 /**
137  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
138  */
139 int nfs_sync_mapping(struct address_space *mapping)
140 {
141         int ret = 0;
142 
143         if (mapping->nrpages != 0) {
144                 unmap_mapping_range(mapping, 0, 0, 0);
145                 ret = nfs_wb_all(mapping->host);
146         }
147         return ret;
148 }
149 
150 static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
151 {
152         struct nfs_inode *nfsi = NFS_I(inode);
153 
154         if (inode->i_mapping->nrpages == 0)
155                 flags &= ~NFS_INO_INVALID_DATA;
156         nfsi->cache_validity |= flags;
157         if (flags & NFS_INO_INVALID_DATA)
158                 nfs_fscache_invalidate(inode);
159 }
160 
161 /*
162  * Invalidate the local caches
163  */
164 static void nfs_zap_caches_locked(struct inode *inode)
165 {
166         struct nfs_inode *nfsi = NFS_I(inode);
167         int mode = inode->i_mode;
168 
169         nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
170 
171         nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
172         nfsi->attrtimeo_timestamp = jiffies;
173 
174         memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
175         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
176                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
177                                         | NFS_INO_INVALID_DATA
178                                         | NFS_INO_INVALID_ACCESS
179                                         | NFS_INO_INVALID_ACL
180                                         | NFS_INO_REVAL_PAGECACHE);
181         } else
182                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
183                                         | NFS_INO_INVALID_ACCESS
184                                         | NFS_INO_INVALID_ACL
185                                         | NFS_INO_REVAL_PAGECACHE);
186         nfs_zap_label_cache_locked(nfsi);
187 }
188 
189 void nfs_zap_caches(struct inode *inode)
190 {
191         spin_lock(&inode->i_lock);
192         nfs_zap_caches_locked(inode);
193         spin_unlock(&inode->i_lock);
194 }
195 EXPORT_SYMBOL_GPL(nfs_zap_caches);
196 
197 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
198 {
199         if (mapping->nrpages != 0) {
200                 spin_lock(&inode->i_lock);
201                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
202                 spin_unlock(&inode->i_lock);
203         }
204 }
205 
206 void nfs_zap_acl_cache(struct inode *inode)
207 {
208         void (*clear_acl_cache)(struct inode *);
209 
210         clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
211         if (clear_acl_cache != NULL)
212                 clear_acl_cache(inode);
213         spin_lock(&inode->i_lock);
214         NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
215         spin_unlock(&inode->i_lock);
216 }
217 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
218 
219 void nfs_invalidate_atime(struct inode *inode)
220 {
221         spin_lock(&inode->i_lock);
222         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
223         spin_unlock(&inode->i_lock);
224 }
225 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
226 
227 /*
228  * Invalidate, but do not unhash, the inode.
229  * NB: must be called with inode->i_lock held!
230  */
231 static void nfs_invalidate_inode(struct inode *inode)
232 {
233         set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
234         nfs_zap_caches_locked(inode);
235 }
236 
237 struct nfs_find_desc {
238         struct nfs_fh           *fh;
239         struct nfs_fattr        *fattr;
240 };
241 
242 /*
243  * In NFSv3 we can have 64bit inode numbers. In order to support
244  * this, and re-exported directories (also seen in NFSv2)
245  * we are forced to allow 2 different inodes to have the same
246  * i_ino.
247  */
248 static int
249 nfs_find_actor(struct inode *inode, void *opaque)
250 {
251         struct nfs_find_desc    *desc = (struct nfs_find_desc *)opaque;
252         struct nfs_fh           *fh = desc->fh;
253         struct nfs_fattr        *fattr = desc->fattr;
254 
255         if (NFS_FILEID(inode) != fattr->fileid)
256                 return 0;
257         if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
258                 return 0;
259         if (nfs_compare_fh(NFS_FH(inode), fh))
260                 return 0;
261         if (is_bad_inode(inode) || NFS_STALE(inode))
262                 return 0;
263         return 1;
264 }
265 
266 static int
267 nfs_init_locked(struct inode *inode, void *opaque)
268 {
269         struct nfs_find_desc    *desc = (struct nfs_find_desc *)opaque;
270         struct nfs_fattr        *fattr = desc->fattr;
271 
272         set_nfs_fileid(inode, fattr->fileid);
273         nfs_copy_fh(NFS_FH(inode), desc->fh);
274         return 0;
275 }
276 
277 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
278 static void nfs_clear_label_invalid(struct inode *inode)
279 {
280         spin_lock(&inode->i_lock);
281         NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
282         spin_unlock(&inode->i_lock);
283 }
284 
285 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
286                                         struct nfs4_label *label)
287 {
288         int error;
289 
290         if (label == NULL)
291                 return;
292 
293         if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
294                 error = security_inode_notifysecctx(inode, label->label,
295                                 label->len);
296                 if (error)
297                         printk(KERN_ERR "%s() %s %d "
298                                         "security_inode_notifysecctx() %d\n",
299                                         __func__,
300                                         (char *)label->label,
301                                         label->len, error);
302                 nfs_clear_label_invalid(inode);
303         }
304 }
305 
306 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
307 {
308         struct nfs4_label *label = NULL;
309         int minor_version = server->nfs_client->cl_minorversion;
310 
311         if (minor_version < 2)
312                 return label;
313 
314         if (!(server->caps & NFS_CAP_SECURITY_LABEL))
315                 return label;
316 
317         label = kzalloc(sizeof(struct nfs4_label), flags);
318         if (label == NULL)
319                 return ERR_PTR(-ENOMEM);
320 
321         label->label = kzalloc(NFS4_MAXLABELLEN, flags);
322         if (label->label == NULL) {
323                 kfree(label);
324                 return ERR_PTR(-ENOMEM);
325         }
326         label->len = NFS4_MAXLABELLEN;
327 
328         return label;
329 }
330 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
331 #else
332 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
333                                         struct nfs4_label *label)
334 {
335 }
336 #endif
337 EXPORT_SYMBOL_GPL(nfs_setsecurity);
338 
339 /*
340  * This is our front-end to iget that looks up inodes by file handle
341  * instead of inode number.
342  */
343 struct inode *
344 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, struct nfs4_label *label)
345 {
346         struct nfs_find_desc desc = {
347                 .fh     = fh,
348                 .fattr  = fattr
349         };
350         struct inode *inode = ERR_PTR(-ENOENT);
351         unsigned long hash;
352 
353         nfs_attr_check_mountpoint(sb, fattr);
354 
355         if (nfs_attr_use_mounted_on_fileid(fattr))
356                 fattr->fileid = fattr->mounted_on_fileid;
357         else if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
358                 goto out_no_inode;
359         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
360                 goto out_no_inode;
361 
362         hash = nfs_fattr_to_ino_t(fattr);
363 
364         inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
365         if (inode == NULL) {
366                 inode = ERR_PTR(-ENOMEM);
367                 goto out_no_inode;
368         }
369 
370         if (inode->i_state & I_NEW) {
371                 struct nfs_inode *nfsi = NFS_I(inode);
372                 unsigned long now = jiffies;
373 
374                 /* We set i_ino for the few things that still rely on it,
375                  * such as stat(2) */
376                 inode->i_ino = hash;
377 
378                 /* We can't support update_atime(), since the server will reset it */
379                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
380                 inode->i_mode = fattr->mode;
381                 if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
382                                 && nfs_server_capable(inode, NFS_CAP_MODE))
383                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
384                 /* Why so? Because we want revalidate for devices/FIFOs, and
385                  * that's precisely what we have in nfs_file_inode_operations.
386                  */
387                 inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
388                 if (S_ISREG(inode->i_mode)) {
389                         inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
390                         inode->i_data.a_ops = &nfs_file_aops;
391                 } else if (S_ISDIR(inode->i_mode)) {
392                         inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
393                         inode->i_fop = &nfs_dir_operations;
394                         inode->i_data.a_ops = &nfs_dir_aops;
395                         /* Deal with crossing mountpoints */
396                         if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
397                                         fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
398                                 if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
399                                         inode->i_op = &nfs_referral_inode_operations;
400                                 else
401                                         inode->i_op = &nfs_mountpoint_inode_operations;
402                                 inode->i_fop = NULL;
403                                 inode->i_flags |= S_AUTOMOUNT;
404                         }
405                 } else if (S_ISLNK(inode->i_mode))
406                         inode->i_op = &nfs_symlink_inode_operations;
407                 else
408                         init_special_inode(inode, inode->i_mode, fattr->rdev);
409 
410                 memset(&inode->i_atime, 0, sizeof(inode->i_atime));
411                 memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
412                 memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
413                 inode->i_version = 0;
414                 inode->i_size = 0;
415                 clear_nlink(inode);
416                 inode->i_uid = make_kuid(&init_user_ns, -2);
417                 inode->i_gid = make_kgid(&init_user_ns, -2);
418                 inode->i_blocks = 0;
419                 memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
420                 nfsi->write_io = 0;
421                 nfsi->read_io = 0;
422 
423                 nfsi->read_cache_jiffies = fattr->time_start;
424                 nfsi->attr_gencount = fattr->gencount;
425                 if (fattr->valid & NFS_ATTR_FATTR_ATIME)
426                         inode->i_atime = fattr->atime;
427                 else if (nfs_server_capable(inode, NFS_CAP_ATIME))
428                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
429                 if (fattr->valid & NFS_ATTR_FATTR_MTIME)
430                         inode->i_mtime = fattr->mtime;
431                 else if (nfs_server_capable(inode, NFS_CAP_MTIME))
432                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
433                 if (fattr->valid & NFS_ATTR_FATTR_CTIME)
434                         inode->i_ctime = fattr->ctime;
435                 else if (nfs_server_capable(inode, NFS_CAP_CTIME))
436                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
437                 if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
438                         inode->i_version = fattr->change_attr;
439                 else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
440                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
441                 if (fattr->valid & NFS_ATTR_FATTR_SIZE)
442                         inode->i_size = nfs_size_to_loff_t(fattr->size);
443                 else
444                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
445                                 | NFS_INO_REVAL_PAGECACHE);
446                 if (fattr->valid & NFS_ATTR_FATTR_NLINK)
447                         set_nlink(inode, fattr->nlink);
448                 else if (nfs_server_capable(inode, NFS_CAP_NLINK))
449                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
450                 if (fattr->valid & NFS_ATTR_FATTR_OWNER)
451                         inode->i_uid = fattr->uid;
452                 else if (nfs_server_capable(inode, NFS_CAP_OWNER))
453                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
454                 if (fattr->valid & NFS_ATTR_FATTR_GROUP)
455                         inode->i_gid = fattr->gid;
456                 else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
457                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
458                 if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
459                         inode->i_blocks = fattr->du.nfs2.blocks;
460                 if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
461                         /*
462                          * report the blocks in 512byte units
463                          */
464                         inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
465                 }
466 
467                 nfs_setsecurity(inode, fattr, label);
468 
469                 nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
470                 nfsi->attrtimeo_timestamp = now;
471                 nfsi->access_cache = RB_ROOT;
472 
473                 nfs_fscache_init_inode(inode);
474 
475                 unlock_new_inode(inode);
476         } else
477                 nfs_refresh_inode(inode, fattr);
478         dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
479                 inode->i_sb->s_id,
480                 (unsigned long long)NFS_FILEID(inode),
481                 nfs_display_fhandle_hash(fh),
482                 atomic_read(&inode->i_count));
483 
484 out:
485         return inode;
486 
487 out_no_inode:
488         dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
489         goto out;
490 }
491 EXPORT_SYMBOL_GPL(nfs_fhget);
492 
493 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
494 
495 int
496 nfs_setattr(struct dentry *dentry, struct iattr *attr)
497 {
498         struct inode *inode = dentry->d_inode;
499         struct nfs_fattr *fattr;
500         int error = -ENOMEM;
501 
502         nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
503 
504         /* skip mode change if it's just for clearing setuid/setgid */
505         if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
506                 attr->ia_valid &= ~ATTR_MODE;
507 
508         if (attr->ia_valid & ATTR_SIZE) {
509                 loff_t i_size;
510 
511                 BUG_ON(!S_ISREG(inode->i_mode));
512 
513                 i_size = i_size_read(inode);
514                 if (attr->ia_size == i_size)
515                         attr->ia_valid &= ~ATTR_SIZE;
516                 else if (attr->ia_size < i_size && IS_SWAPFILE(inode))
517                         return -ETXTBSY;
518         }
519 
520         /* Optimization: if the end result is no change, don't RPC */
521         attr->ia_valid &= NFS_VALID_ATTRS;
522         if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
523                 return 0;
524 
525         trace_nfs_setattr_enter(inode);
526 
527         /* Write all dirty data */
528         if (S_ISREG(inode->i_mode)) {
529                 nfs_inode_dio_wait(inode);
530                 nfs_wb_all(inode);
531         }
532 
533         fattr = nfs_alloc_fattr();
534         if (fattr == NULL)
535                 goto out;
536         /*
537          * Return any delegations if we're going to change ACLs
538          */
539         if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
540                 NFS_PROTO(inode)->return_delegation(inode);
541         error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
542         if (error == 0)
543                 error = nfs_refresh_inode(inode, fattr);
544         nfs_free_fattr(fattr);
545 out:
546         trace_nfs_setattr_exit(inode, error);
547         return error;
548 }
549 EXPORT_SYMBOL_GPL(nfs_setattr);
550 
551 /**
552  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
553  * @inode: inode of the file used
554  * @offset: file offset to start truncating
555  *
556  * This is a copy of the common vmtruncate, but with the locking
557  * corrected to take into account the fact that NFS requires
558  * inode->i_size to be updated under the inode->i_lock.
559  * Note: must be called with inode->i_lock held!
560  */
561 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
562 {
563         int err;
564 
565         err = inode_newsize_ok(inode, offset);
566         if (err)
567                 goto out;
568 
569         i_size_write(inode, offset);
570         /* Optimisation */
571         if (offset == 0)
572                 NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
573 
574         spin_unlock(&inode->i_lock);
575         truncate_pagecache(inode, offset);
576         spin_lock(&inode->i_lock);
577 out:
578         return err;
579 }
580 
581 /**
582  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
583  * @inode: pointer to struct inode
584  * @attr: pointer to struct iattr
585  *
586  * Note: we do this in the *proc.c in order to ensure that
587  *       it works for things like exclusive creates too.
588  */
589 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
590                 struct nfs_fattr *fattr)
591 {
592         /* Barrier: bump the attribute generation count. */
593         nfs_fattr_set_barrier(fattr);
594 
595         spin_lock(&inode->i_lock);
596         NFS_I(inode)->attr_gencount = fattr->gencount;
597         if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
598                 if ((attr->ia_valid & ATTR_MODE) != 0) {
599                         int mode = attr->ia_mode & S_IALLUGO;
600                         mode |= inode->i_mode & ~S_IALLUGO;
601                         inode->i_mode = mode;
602                 }
603                 if ((attr->ia_valid & ATTR_UID) != 0)
604                         inode->i_uid = attr->ia_uid;
605                 if ((attr->ia_valid & ATTR_GID) != 0)
606                         inode->i_gid = attr->ia_gid;
607                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
608                                 | NFS_INO_INVALID_ACL);
609         }
610         if ((attr->ia_valid & ATTR_SIZE) != 0) {
611                 nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
612                 nfs_vmtruncate(inode, attr->ia_size);
613         }
614         nfs_update_inode(inode, fattr);
615         spin_unlock(&inode->i_lock);
616 }
617 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
618 
619 static void nfs_request_parent_use_readdirplus(struct dentry *dentry)
620 {
621         struct dentry *parent;
622 
623         parent = dget_parent(dentry);
624         nfs_force_use_readdirplus(parent->d_inode);
625         dput(parent);
626 }
627 
628 static bool nfs_need_revalidate_inode(struct inode *inode)
629 {
630         if (NFS_I(inode)->cache_validity &
631                         (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
632                 return true;
633         if (nfs_attribute_cache_expired(inode))
634                 return true;
635         return false;
636 }
637 
638 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
639 {
640         struct inode *inode = dentry->d_inode;
641         int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
642         int err = 0;
643 
644         trace_nfs_getattr_enter(inode);
645         /* Flush out writes to the server in order to update c/mtime.  */
646         if (S_ISREG(inode->i_mode)) {
647                 nfs_inode_dio_wait(inode);
648                 err = filemap_write_and_wait(inode->i_mapping);
649                 if (err)
650                         goto out;
651         }
652 
653         /*
654          * We may force a getattr if the user cares about atime.
655          *
656          * Note that we only have to check the vfsmount flags here:
657          *  - NFS always sets S_NOATIME by so checking it would give a
658          *    bogus result
659          *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
660          *    no point in checking those.
661          */
662         if ((mnt->mnt_flags & MNT_NOATIME) ||
663             ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
664                 need_atime = 0;
665 
666         if (need_atime || nfs_need_revalidate_inode(inode)) {
667                 struct nfs_server *server = NFS_SERVER(inode);
668 
669                 if (server->caps & NFS_CAP_READDIRPLUS)
670                         nfs_request_parent_use_readdirplus(dentry);
671                 err = __nfs_revalidate_inode(server, inode);
672         }
673         if (!err) {
674                 generic_fillattr(inode, stat);
675                 stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
676         }
677 out:
678         trace_nfs_getattr_exit(inode, err);
679         return err;
680 }
681 EXPORT_SYMBOL_GPL(nfs_getattr);
682 
683 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
684 {
685         atomic_set(&l_ctx->count, 1);
686         l_ctx->lockowner.l_owner = current->files;
687         l_ctx->lockowner.l_pid = current->tgid;
688         INIT_LIST_HEAD(&l_ctx->list);
689         nfs_iocounter_init(&l_ctx->io_count);
690 }
691 
692 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
693 {
694         struct nfs_lock_context *head = &ctx->lock_context;
695         struct nfs_lock_context *pos = head;
696 
697         do {
698                 if (pos->lockowner.l_owner != current->files)
699                         continue;
700                 if (pos->lockowner.l_pid != current->tgid)
701                         continue;
702                 atomic_inc(&pos->count);
703                 return pos;
704         } while ((pos = list_entry(pos->list.next, typeof(*pos), list)) != head);
705         return NULL;
706 }
707 
708 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
709 {
710         struct nfs_lock_context *res, *new = NULL;
711         struct inode *inode = ctx->dentry->d_inode;
712 
713         spin_lock(&inode->i_lock);
714         res = __nfs_find_lock_context(ctx);
715         if (res == NULL) {
716                 spin_unlock(&inode->i_lock);
717                 new = kmalloc(sizeof(*new), GFP_KERNEL);
718                 if (new == NULL)
719                         return ERR_PTR(-ENOMEM);
720                 nfs_init_lock_context(new);
721                 spin_lock(&inode->i_lock);
722                 res = __nfs_find_lock_context(ctx);
723                 if (res == NULL) {
724                         list_add_tail(&new->list, &ctx->lock_context.list);
725                         new->open_context = ctx;
726                         res = new;
727                         new = NULL;
728                 }
729         }
730         spin_unlock(&inode->i_lock);
731         kfree(new);
732         return res;
733 }
734 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
735 
736 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
737 {
738         struct nfs_open_context *ctx = l_ctx->open_context;
739         struct inode *inode = ctx->dentry->d_inode;
740 
741         if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
742                 return;
743         list_del(&l_ctx->list);
744         spin_unlock(&inode->i_lock);
745         kfree(l_ctx);
746 }
747 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
748 
749 /**
750  * nfs_close_context - Common close_context() routine NFSv2/v3
751  * @ctx: pointer to context
752  * @is_sync: is this a synchronous close
753  *
754  * always ensure that the attributes are up to date if we're mounted
755  * with close-to-open semantics
756  */
757 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
758 {
759         struct inode *inode;
760         struct nfs_server *server;
761 
762         if (!(ctx->mode & FMODE_WRITE))
763                 return;
764         if (!is_sync)
765                 return;
766         inode = ctx->dentry->d_inode;
767         if (!list_empty(&NFS_I(inode)->open_files))
768                 return;
769         server = NFS_SERVER(inode);
770         if (server->flags & NFS_MOUNT_NOCTO)
771                 return;
772         nfs_revalidate_inode(server, inode);
773 }
774 EXPORT_SYMBOL_GPL(nfs_close_context);
775 
776 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
777 {
778         struct nfs_open_context *ctx;
779         struct rpc_cred *cred = rpc_lookup_cred();
780         if (IS_ERR(cred))
781                 return ERR_CAST(cred);
782 
783         ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
784         if (!ctx) {
785                 put_rpccred(cred);
786                 return ERR_PTR(-ENOMEM);
787         }
788         nfs_sb_active(dentry->d_sb);
789         ctx->dentry = dget(dentry);
790         ctx->cred = cred;
791         ctx->state = NULL;
792         ctx->mode = f_mode;
793         ctx->flags = 0;
794         ctx->error = 0;
795         nfs_init_lock_context(&ctx->lock_context);
796         ctx->lock_context.open_context = ctx;
797         INIT_LIST_HEAD(&ctx->list);
798         ctx->mdsthreshold = NULL;
799         return ctx;
800 }
801 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
802 
803 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
804 {
805         if (ctx != NULL)
806                 atomic_inc(&ctx->lock_context.count);
807         return ctx;
808 }
809 EXPORT_SYMBOL_GPL(get_nfs_open_context);
810 
811 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
812 {
813         struct inode *inode = ctx->dentry->d_inode;
814         struct super_block *sb = ctx->dentry->d_sb;
815 
816         if (!list_empty(&ctx->list)) {
817                 if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
818                         return;
819                 list_del(&ctx->list);
820                 spin_unlock(&inode->i_lock);
821         } else if (!atomic_dec_and_test(&ctx->lock_context.count))
822                 return;
823         if (inode != NULL)
824                 NFS_PROTO(inode)->close_context(ctx, is_sync);
825         if (ctx->cred != NULL)
826                 put_rpccred(ctx->cred);
827         dput(ctx->dentry);
828         nfs_sb_deactive(sb);
829         kfree(ctx->mdsthreshold);
830         kfree(ctx);
831 }
832 
833 void put_nfs_open_context(struct nfs_open_context *ctx)
834 {
835         __put_nfs_open_context(ctx, 0);
836 }
837 EXPORT_SYMBOL_GPL(put_nfs_open_context);
838 
839 /*
840  * Ensure that mmap has a recent RPC credential for use when writing out
841  * shared pages
842  */
843 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
844 {
845         struct inode *inode = ctx->dentry->d_inode;
846         struct nfs_inode *nfsi = NFS_I(inode);
847 
848         spin_lock(&inode->i_lock);
849         list_add(&ctx->list, &nfsi->open_files);
850         spin_unlock(&inode->i_lock);
851 }
852 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
853 
854 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
855 {
856         filp->private_data = get_nfs_open_context(ctx);
857         if (list_empty(&ctx->list))
858                 nfs_inode_attach_open_context(ctx);
859 }
860 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
861 
862 /*
863  * Given an inode, search for an open context with the desired characteristics
864  */
865 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
866 {
867         struct nfs_inode *nfsi = NFS_I(inode);
868         struct nfs_open_context *pos, *ctx = NULL;
869 
870         spin_lock(&inode->i_lock);
871         list_for_each_entry(pos, &nfsi->open_files, list) {
872                 if (cred != NULL && pos->cred != cred)
873                         continue;
874                 if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
875                         continue;
876                 ctx = get_nfs_open_context(pos);
877                 break;
878         }
879         spin_unlock(&inode->i_lock);
880         return ctx;
881 }
882 
883 static void nfs_file_clear_open_context(struct file *filp)
884 {
885         struct nfs_open_context *ctx = nfs_file_open_context(filp);
886 
887         if (ctx) {
888                 struct inode *inode = ctx->dentry->d_inode;
889 
890                 filp->private_data = NULL;
891                 spin_lock(&inode->i_lock);
892                 list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
893                 spin_unlock(&inode->i_lock);
894                 __put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
895         }
896 }
897 
898 /*
899  * These allocate and release file read/write context information.
900  */
901 int nfs_open(struct inode *inode, struct file *filp)
902 {
903         struct nfs_open_context *ctx;
904 
905         ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
906         if (IS_ERR(ctx))
907                 return PTR_ERR(ctx);
908         nfs_file_set_open_context(filp, ctx);
909         put_nfs_open_context(ctx);
910         nfs_fscache_open_file(inode, filp);
911         return 0;
912 }
913 
914 int nfs_release(struct inode *inode, struct file *filp)
915 {
916         nfs_file_clear_open_context(filp);
917         return 0;
918 }
919 
920 /*
921  * This function is called whenever some part of NFS notices that
922  * the cached attributes have to be refreshed.
923  */
924 int
925 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
926 {
927         int              status = -ESTALE;
928         struct nfs4_label *label = NULL;
929         struct nfs_fattr *fattr = NULL;
930         struct nfs_inode *nfsi = NFS_I(inode);
931 
932         dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
933                 inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
934 
935         trace_nfs_revalidate_inode_enter(inode);
936 
937         if (is_bad_inode(inode))
938                 goto out;
939         if (NFS_STALE(inode))
940                 goto out;
941 
942         status = -ENOMEM;
943         fattr = nfs_alloc_fattr();
944         if (fattr == NULL)
945                 goto out;
946 
947         nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
948 
949         label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
950         if (IS_ERR(label)) {
951                 status = PTR_ERR(label);
952                 goto out;
953         }
954 
955         status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, label);
956         if (status != 0) {
957                 dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
958                          inode->i_sb->s_id,
959                          (unsigned long long)NFS_FILEID(inode), status);
960                 if (status == -ESTALE) {
961                         nfs_zap_caches(inode);
962                         if (!S_ISDIR(inode->i_mode))
963                                 set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
964                 }
965                 goto err_out;
966         }
967 
968         status = nfs_refresh_inode(inode, fattr);
969         if (status) {
970                 dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
971                          inode->i_sb->s_id,
972                          (unsigned long long)NFS_FILEID(inode), status);
973                 goto err_out;
974         }
975 
976         if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
977                 nfs_zap_acl_cache(inode);
978 
979         nfs_setsecurity(inode, fattr, label);
980 
981         dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
982                 inode->i_sb->s_id,
983                 (unsigned long long)NFS_FILEID(inode));
984 
985 err_out:
986         nfs4_label_free(label);
987 out:
988         nfs_free_fattr(fattr);
989         trace_nfs_revalidate_inode_exit(inode, status);
990         return status;
991 }
992 
993 int nfs_attribute_timeout(struct inode *inode)
994 {
995         struct nfs_inode *nfsi = NFS_I(inode);
996 
997         return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
998 }
999 
1000 int nfs_attribute_cache_expired(struct inode *inode)
1001 {
1002         if (nfs_have_delegated_attributes(inode))
1003                 return 0;
1004         return nfs_attribute_timeout(inode);
1005 }
1006 
1007 /**
1008  * nfs_revalidate_inode - Revalidate the inode attributes
1009  * @server - pointer to nfs_server struct
1010  * @inode - pointer to inode struct
1011  *
1012  * Updates inode attribute information by retrieving the data from the server.
1013  */
1014 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1015 {
1016         if (!nfs_need_revalidate_inode(inode))
1017                 return NFS_STALE(inode) ? -ESTALE : 0;
1018         return __nfs_revalidate_inode(server, inode);
1019 }
1020 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1021 
1022 int nfs_revalidate_inode_rcu(struct nfs_server *server, struct inode *inode)
1023 {
1024         if (!(NFS_I(inode)->cache_validity &
1025                         (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
1026                         && !nfs_attribute_cache_expired(inode))
1027                 return NFS_STALE(inode) ? -ESTALE : 0;
1028         return -ECHILD;
1029 }
1030 
1031 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1032 {
1033         struct nfs_inode *nfsi = NFS_I(inode);
1034         int ret;
1035 
1036         if (mapping->nrpages != 0) {
1037                 if (S_ISREG(inode->i_mode)) {
1038                         unmap_mapping_range(mapping, 0, 0, 0);
1039                         ret = nfs_sync_mapping(mapping);
1040                         if (ret < 0)
1041                                 return ret;
1042                 }
1043                 ret = invalidate_inode_pages2(mapping);
1044                 if (ret < 0)
1045                         return ret;
1046         }
1047         if (S_ISDIR(inode->i_mode)) {
1048                 spin_lock(&inode->i_lock);
1049                 memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
1050                 spin_unlock(&inode->i_lock);
1051         }
1052         nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1053         nfs_fscache_wait_on_invalidate(inode);
1054 
1055         dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1056                         inode->i_sb->s_id,
1057                         (unsigned long long)NFS_FILEID(inode));
1058         return 0;
1059 }
1060 
1061 static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1062 {
1063         if (nfs_have_delegated_attributes(inode))
1064                 return false;
1065         return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
1066                 || nfs_attribute_timeout(inode)
1067                 || NFS_STALE(inode);
1068 }
1069 
1070 /**
1071  * __nfs_revalidate_mapping - Revalidate the pagecache
1072  * @inode - pointer to host inode
1073  * @mapping - pointer to mapping
1074  * @may_lock - take inode->i_mutex?
1075  */
1076 static int __nfs_revalidate_mapping(struct inode *inode,
1077                 struct address_space *mapping,
1078                 bool may_lock)
1079 {
1080         struct nfs_inode *nfsi = NFS_I(inode);
1081         unsigned long *bitlock = &nfsi->flags;
1082         int ret = 0;
1083 
1084         /* swapfiles are not supposed to be shared. */
1085         if (IS_SWAPFILE(inode))
1086                 goto out;
1087 
1088         if (nfs_mapping_need_revalidate_inode(inode)) {
1089                 ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1090                 if (ret < 0)
1091                         goto out;
1092         }
1093 
1094         /*
1095          * We must clear NFS_INO_INVALID_DATA first to ensure that
1096          * invalidations that come in while we're shooting down the mappings
1097          * are respected. But, that leaves a race window where one revalidator
1098          * can clear the flag, and then another checks it before the mapping
1099          * gets invalidated. Fix that by serializing access to this part of
1100          * the function.
1101          *
1102          * At the same time, we need to allow other tasks to see whether we
1103          * might be in the middle of invalidating the pages, so we only set
1104          * the bit lock here if it looks like we're going to be doing that.
1105          */
1106         for (;;) {
1107                 ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1108                                          nfs_wait_bit_killable, TASK_KILLABLE);
1109                 if (ret)
1110                         goto out;
1111                 spin_lock(&inode->i_lock);
1112                 if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1113                         spin_unlock(&inode->i_lock);
1114                         continue;
1115                 }
1116                 if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1117                         break;
1118                 spin_unlock(&inode->i_lock);
1119                 goto out;
1120         }
1121 
1122         set_bit(NFS_INO_INVALIDATING, bitlock);
1123         smp_wmb();
1124         nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1125         spin_unlock(&inode->i_lock);
1126         trace_nfs_invalidate_mapping_enter(inode);
1127         if (may_lock) {
1128                 mutex_lock(&inode->i_mutex);
1129                 ret = nfs_invalidate_mapping(inode, mapping);
1130                 mutex_unlock(&inode->i_mutex);
1131         } else
1132                 ret = nfs_invalidate_mapping(inode, mapping);
1133         trace_nfs_invalidate_mapping_exit(inode, ret);
1134 
1135         clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1136         smp_mb__after_atomic();
1137         wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1138 out:
1139         return ret;
1140 }
1141 
1142 /**
1143  * nfs_revalidate_mapping - Revalidate the pagecache
1144  * @inode - pointer to host inode
1145  * @mapping - pointer to mapping
1146  */
1147 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1148 {
1149         return __nfs_revalidate_mapping(inode, mapping, false);
1150 }
1151 
1152 /**
1153  * nfs_revalidate_mapping_protected - Revalidate the pagecache
1154  * @inode - pointer to host inode
1155  * @mapping - pointer to mapping
1156  *
1157  * Differs from nfs_revalidate_mapping() in that it grabs the inode->i_mutex
1158  * while invalidating the mapping.
1159  */
1160 int nfs_revalidate_mapping_protected(struct inode *inode, struct address_space *mapping)
1161 {
1162         return __nfs_revalidate_mapping(inode, mapping, true);
1163 }
1164 
1165 static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1166 {
1167         struct nfs_inode *nfsi = NFS_I(inode);
1168         unsigned long ret = 0;
1169 
1170         if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1171                         && (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1172                         && inode->i_version == fattr->pre_change_attr) {
1173                 inode->i_version = fattr->change_attr;
1174                 if (S_ISDIR(inode->i_mode))
1175                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1176                 ret |= NFS_INO_INVALID_ATTR;
1177         }
1178         /* If we have atomic WCC data, we may update some attributes */
1179         if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1180                         && (fattr->valid & NFS_ATTR_FATTR_CTIME)
1181                         && timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
1182                 memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1183                 ret |= NFS_INO_INVALID_ATTR;
1184         }
1185 
1186         if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1187                         && (fattr->valid & NFS_ATTR_FATTR_MTIME)
1188                         && timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
1189                 memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1190                 if (S_ISDIR(inode->i_mode))
1191                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1192                 ret |= NFS_INO_INVALID_ATTR;
1193         }
1194         if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1195                         && (fattr->valid & NFS_ATTR_FATTR_SIZE)
1196                         && i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1197                         && nfsi->nrequests == 0) {
1198                 i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1199                 ret |= NFS_INO_INVALID_ATTR;
1200         }
1201 
1202         return ret;
1203 }
1204 
1205 /**
1206  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1207  * @inode - pointer to inode
1208  * @fattr - updated attributes
1209  *
1210  * Verifies the attribute cache. If we have just changed the attributes,
1211  * so that fattr carries weak cache consistency data, then it may
1212  * also update the ctime/mtime/change_attribute.
1213  */
1214 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1215 {
1216         struct nfs_inode *nfsi = NFS_I(inode);
1217         loff_t cur_size, new_isize;
1218         unsigned long invalid = 0;
1219 
1220 
1221         if (nfs_have_delegated_attributes(inode))
1222                 return 0;
1223         /* Has the inode gone and changed behind our back? */
1224         if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
1225                 return -EIO;
1226         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1227                 return -EIO;
1228 
1229         if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1230                         inode->i_version != fattr->change_attr)
1231                 invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1232 
1233         /* Verify a few of the more important attributes */
1234         if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
1235                 invalid |= NFS_INO_INVALID_ATTR;
1236 
1237         if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1238                 cur_size = i_size_read(inode);
1239                 new_isize = nfs_size_to_loff_t(fattr->size);
1240                 if (cur_size != new_isize && nfsi->nrequests == 0)
1241                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1242         }
1243 
1244         /* Have any file permissions changed? */
1245         if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1246                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1247         if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1248                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1249         if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1250                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1251 
1252         /* Has the link count changed? */
1253         if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1254                 invalid |= NFS_INO_INVALID_ATTR;
1255 
1256         if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
1257                 invalid |= NFS_INO_INVALID_ATIME;
1258 
1259         if (invalid != 0)
1260                 nfs_set_cache_invalid(inode, invalid);
1261 
1262         nfsi->read_cache_jiffies = fattr->time_start;
1263         return 0;
1264 }
1265 
1266 static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1267 {
1268         if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
1269                 return 0;
1270         return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
1271 }
1272 
1273 static atomic_long_t nfs_attr_generation_counter;
1274 
1275 static unsigned long nfs_read_attr_generation_counter(void)
1276 {
1277         return atomic_long_read(&nfs_attr_generation_counter);
1278 }
1279 
1280 unsigned long nfs_inc_attr_generation_counter(void)
1281 {
1282         return atomic_long_inc_return(&nfs_attr_generation_counter);
1283 }
1284 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1285 
1286 void nfs_fattr_init(struct nfs_fattr *fattr)
1287 {
1288         fattr->valid = 0;
1289         fattr->time_start = jiffies;
1290         fattr->gencount = nfs_inc_attr_generation_counter();
1291         fattr->owner_name = NULL;
1292         fattr->group_name = NULL;
1293 }
1294 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1295 
1296 /**
1297  * nfs_fattr_set_barrier
1298  * @fattr: attributes
1299  *
1300  * Used to set a barrier after an attribute was updated. This
1301  * barrier ensures that older attributes from RPC calls that may
1302  * have raced with our update cannot clobber these new values.
1303  * Note that you are still responsible for ensuring that other
1304  * operations which change the attribute on the server do not
1305  * collide.
1306  */
1307 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1308 {
1309         fattr->gencount = nfs_inc_attr_generation_counter();
1310 }
1311 
1312 struct nfs_fattr *nfs_alloc_fattr(void)
1313 {
1314         struct nfs_fattr *fattr;
1315 
1316         fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1317         if (fattr != NULL)
1318                 nfs_fattr_init(fattr);
1319         return fattr;
1320 }
1321 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1322 
1323 struct nfs_fh *nfs_alloc_fhandle(void)
1324 {
1325         struct nfs_fh *fh;
1326 
1327         fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1328         if (fh != NULL)
1329                 fh->size = 0;
1330         return fh;
1331 }
1332 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1333 
1334 #ifdef NFS_DEBUG
1335 /*
1336  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1337  *                             in the same way that wireshark does
1338  *
1339  * @fh: file handle
1340  *
1341  * For debugging only.
1342  */
1343 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1344 {
1345         /* wireshark uses 32-bit AUTODIN crc and does a bitwise
1346          * not on the result */
1347         return nfs_fhandle_hash(fh);
1348 }
1349 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1350 
1351 /*
1352  * _nfs_display_fhandle - display an NFS file handle on the console
1353  *
1354  * @fh: file handle to display
1355  * @caption: display caption
1356  *
1357  * For debugging only.
1358  */
1359 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1360 {
1361         unsigned short i;
1362 
1363         if (fh == NULL || fh->size == 0) {
1364                 printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1365                 return;
1366         }
1367 
1368         printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1369                caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1370         for (i = 0; i < fh->size; i += 16) {
1371                 __be32 *pos = (__be32 *)&fh->data[i];
1372 
1373                 switch ((fh->size - i - 1) >> 2) {
1374                 case 0:
1375                         printk(KERN_DEFAULT " %08x\n",
1376                                 be32_to_cpup(pos));
1377                         break;
1378                 case 1:
1379                         printk(KERN_DEFAULT " %08x %08x\n",
1380                                 be32_to_cpup(pos), be32_to_cpup(pos + 1));
1381                         break;
1382                 case 2:
1383                         printk(KERN_DEFAULT " %08x %08x %08x\n",
1384                                 be32_to_cpup(pos), be32_to_cpup(pos + 1),
1385                                 be32_to_cpup(pos + 2));
1386                         break;
1387                 default:
1388                         printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1389                                 be32_to_cpup(pos), be32_to_cpup(pos + 1),
1390                                 be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1391                 }
1392         }
1393 }
1394 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1395 #endif
1396 
1397 /**
1398  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1399  * @inode - pointer to inode
1400  * @fattr - attributes
1401  *
1402  * Attempt to divine whether or not an RPC call reply carrying stale
1403  * attributes got scheduled after another call carrying updated ones.
1404  *
1405  * To do so, the function first assumes that a more recent ctime means
1406  * that the attributes in fattr are newer, however it also attempt to
1407  * catch the case where ctime either didn't change, or went backwards
1408  * (if someone reset the clock on the server) by looking at whether
1409  * or not this RPC call was started after the inode was last updated.
1410  * Note also the check for wraparound of 'attr_gencount'
1411  *
1412  * The function returns 'true' if it thinks the attributes in 'fattr' are
1413  * more recent than the ones cached in the inode.
1414  *
1415  */
1416 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1417 {
1418         const struct nfs_inode *nfsi = NFS_I(inode);
1419 
1420         return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1421                 nfs_ctime_need_update(inode, fattr) ||
1422                 ((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1423 }
1424 
1425 /*
1426  * Don't trust the change_attribute, mtime, ctime or size if
1427  * a pnfs LAYOUTCOMMIT is outstanding
1428  */
1429 static void nfs_inode_attrs_handle_layoutcommit(struct inode *inode,
1430                 struct nfs_fattr *fattr)
1431 {
1432         if (pnfs_layoutcommit_outstanding(inode))
1433                 fattr->valid &= ~(NFS_ATTR_FATTR_CHANGE |
1434                                 NFS_ATTR_FATTR_MTIME |
1435                                 NFS_ATTR_FATTR_CTIME |
1436                                 NFS_ATTR_FATTR_SIZE);
1437 }
1438 
1439 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1440 {
1441         int ret;
1442 
1443         trace_nfs_refresh_inode_enter(inode);
1444 
1445         nfs_inode_attrs_handle_layoutcommit(inode, fattr);
1446 
1447         if (nfs_inode_attrs_need_update(inode, fattr))
1448                 ret = nfs_update_inode(inode, fattr);
1449         else
1450                 ret = nfs_check_inode_attributes(inode, fattr);
1451 
1452         trace_nfs_refresh_inode_exit(inode, ret);
1453         return ret;
1454 }
1455 
1456 /**
1457  * nfs_refresh_inode - try to update the inode attribute cache
1458  * @inode - pointer to inode
1459  * @fattr - updated attributes
1460  *
1461  * Check that an RPC call that returned attributes has not overlapped with
1462  * other recent updates of the inode metadata, then decide whether it is
1463  * safe to do a full update of the inode attributes, or whether just to
1464  * call nfs_check_inode_attributes.
1465  */
1466 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1467 {
1468         int status;
1469 
1470         if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1471                 return 0;
1472         spin_lock(&inode->i_lock);
1473         status = nfs_refresh_inode_locked(inode, fattr);
1474         spin_unlock(&inode->i_lock);
1475 
1476         return status;
1477 }
1478 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
1479 
1480 static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1481 {
1482         unsigned long invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1483 
1484         if (S_ISDIR(inode->i_mode))
1485                 invalid |= NFS_INO_INVALID_DATA;
1486         nfs_set_cache_invalid(inode, invalid);
1487         if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1488                 return 0;
1489         return nfs_refresh_inode_locked(inode, fattr);
1490 }
1491 
1492 /**
1493  * nfs_post_op_update_inode - try to update the inode attribute cache
1494  * @inode - pointer to inode
1495  * @fattr - updated attributes
1496  *
1497  * After an operation that has changed the inode metadata, mark the
1498  * attribute cache as being invalid, then try to update it.
1499  *
1500  * NB: if the server didn't return any post op attributes, this
1501  * function will force the retrieval of attributes before the next
1502  * NFS request.  Thus it should be used only for operations that
1503  * are expected to change one or more attributes, to avoid
1504  * unnecessary NFS requests and trips through nfs_update_inode().
1505  */
1506 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1507 {
1508         int status;
1509 
1510         spin_lock(&inode->i_lock);
1511         nfs_fattr_set_barrier(fattr);
1512         status = nfs_post_op_update_inode_locked(inode, fattr);
1513         spin_unlock(&inode->i_lock);
1514 
1515         return status;
1516 }
1517 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
1518 
1519 /**
1520  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
1521  * @inode - pointer to inode
1522  * @fattr - updated attributes
1523  *
1524  * After an operation that has changed the inode metadata, mark the
1525  * attribute cache as being invalid, then try to update it. Fake up
1526  * weak cache consistency data, if none exist.
1527  *
1528  * This function is mainly designed to be used by the ->write_done() functions.
1529  */
1530 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
1531 {
1532         int status;
1533 
1534         /* Don't do a WCC update if these attributes are already stale */
1535         if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1536                         !nfs_inode_attrs_need_update(inode, fattr)) {
1537                 fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1538                                 | NFS_ATTR_FATTR_PRESIZE
1539                                 | NFS_ATTR_FATTR_PREMTIME
1540                                 | NFS_ATTR_FATTR_PRECTIME);
1541                 goto out_noforce;
1542         }
1543         if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1544                         (fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1545                 fattr->pre_change_attr = inode->i_version;
1546                 fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1547         }
1548         if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1549                         (fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1550                 memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
1551                 fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1552         }
1553         if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1554                         (fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1555                 memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
1556                 fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1557         }
1558         if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1559                         (fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1560                 fattr->pre_size = i_size_read(inode);
1561                 fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1562         }
1563 out_noforce:
1564         status = nfs_post_op_update_inode_locked(inode, fattr);
1565         return status;
1566 }
1567 
1568 /**
1569  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1570  * @inode - pointer to inode
1571  * @fattr - updated attributes
1572  *
1573  * After an operation that has changed the inode metadata, mark the
1574  * attribute cache as being invalid, then try to update it. Fake up
1575  * weak cache consistency data, if none exist.
1576  *
1577  * This function is mainly designed to be used by the ->write_done() functions.
1578  */
1579 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1580 {
1581         int status;
1582 
1583         spin_lock(&inode->i_lock);
1584         nfs_fattr_set_barrier(fattr);
1585         status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
1586         spin_unlock(&inode->i_lock);
1587         return status;
1588 }
1589 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
1590 
1591 /*
1592  * Many nfs protocol calls return the new file attributes after
1593  * an operation.  Here we update the inode to reflect the state
1594  * of the server's inode.
1595  *
1596  * This is a bit tricky because we have to make sure all dirty pages
1597  * have been sent off to the server before calling invalidate_inode_pages.
1598  * To make sure no other process adds more write requests while we try
1599  * our best to flush them, we make them sleep during the attribute refresh.
1600  *
1601  * A very similar scenario holds for the dir cache.
1602  */
1603 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1604 {
1605         struct nfs_server *server;
1606         struct nfs_inode *nfsi = NFS_I(inode);
1607         loff_t cur_isize, new_isize;
1608         unsigned long invalid = 0;
1609         unsigned long now = jiffies;
1610         unsigned long save_cache_validity;
1611 
1612         dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%x)\n",
1613                         __func__, inode->i_sb->s_id, inode->i_ino,
1614                         nfs_display_fhandle_hash(NFS_FH(inode)),
1615                         atomic_read(&inode->i_count), fattr->valid);
1616 
1617         if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid) {
1618                 printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1619                         "fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1620                         NFS_SERVER(inode)->nfs_client->cl_hostname,
1621                         inode->i_sb->s_id, (long long)nfsi->fileid,
1622                         (long long)fattr->fileid);
1623                 goto out_err;
1624         }
1625 
1626         /*
1627          * Make sure the inode's type hasn't changed.
1628          */
1629         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1630                 /*
1631                 * Big trouble! The inode has become a different object.
1632                 */
1633                 printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
1634                                 __func__, inode->i_ino, inode->i_mode, fattr->mode);
1635                 goto out_err;
1636         }
1637 
1638         server = NFS_SERVER(inode);
1639         /* Update the fsid? */
1640         if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1641                         !nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1642                         !IS_AUTOMOUNT(inode))
1643                 server->fsid = fattr->fsid;
1644 
1645         /*
1646          * Update the read time so we don't revalidate too often.
1647          */
1648         nfsi->read_cache_jiffies = fattr->time_start;
1649 
1650         save_cache_validity = nfsi->cache_validity;
1651         nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1652                         | NFS_INO_INVALID_ATIME
1653                         | NFS_INO_REVAL_FORCED
1654                         | NFS_INO_REVAL_PAGECACHE);
1655 
1656         /* Do atomic weak cache consistency updates */
1657         invalid |= nfs_wcc_update_inode(inode, fattr);
1658 
1659         /* More cache consistency checks */
1660         if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1661                 if (inode->i_version != fattr->change_attr) {
1662                         dprintk("NFS: change_attr change on server for file %s/%ld\n",
1663                                         inode->i_sb->s_id, inode->i_ino);
1664                         invalid |= NFS_INO_INVALID_ATTR
1665                                 | NFS_INO_INVALID_DATA
1666                                 | NFS_INO_INVALID_ACCESS
1667                                 | NFS_INO_INVALID_ACL
1668                                 | NFS_INO_REVAL_PAGECACHE;
1669                         if (S_ISDIR(inode->i_mode))
1670                                 nfs_force_lookup_revalidate(inode);
1671                         inode->i_version = fattr->change_attr;
1672                 }
1673         } else if (server->caps & NFS_CAP_CHANGE_ATTR)
1674                 nfsi->cache_validity |= save_cache_validity;
1675 
1676         if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1677                 memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1678         } else if (server->caps & NFS_CAP_MTIME)
1679                 nfsi->cache_validity |= save_cache_validity &
1680                                 (NFS_INO_INVALID_ATTR
1681                                 | NFS_INO_REVAL_FORCED);
1682 
1683         if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1684                 memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1685         } else if (server->caps & NFS_CAP_CTIME)
1686                 nfsi->cache_validity |= save_cache_validity &
1687                                 (NFS_INO_INVALID_ATTR
1688                                 | NFS_INO_REVAL_FORCED);
1689 
1690         /* Check if our cached file size is stale */
1691         if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1692                 new_isize = nfs_size_to_loff_t(fattr->size);
1693                 cur_isize = i_size_read(inode);
1694                 if (new_isize != cur_isize) {
1695                         /* Do we perhaps have any outstanding writes, or has
1696                          * the file grown beyond our last write? */
1697                         if ((nfsi->nrequests == 0) || new_isize > cur_isize) {
1698                                 i_size_write(inode, new_isize);
1699                                 invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1700                                 invalid &= ~NFS_INO_REVAL_PAGECACHE;
1701                         }
1702                         dprintk("NFS: isize change on server for file %s/%ld "
1703                                         "(%Ld to %Ld)\n",
1704                                         inode->i_sb->s_id,
1705                                         inode->i_ino,
1706                                         (long long)cur_isize,
1707                                         (long long)new_isize);
1708                 }
1709         } else
1710                 nfsi->cache_validity |= save_cache_validity &
1711                                 (NFS_INO_INVALID_ATTR
1712                                 | NFS_INO_REVAL_PAGECACHE
1713                                 | NFS_INO_REVAL_FORCED);
1714 
1715 
1716         if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1717                 memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1718         else if (server->caps & NFS_CAP_ATIME)
1719                 nfsi->cache_validity |= save_cache_validity &
1720                                 (NFS_INO_INVALID_ATIME
1721                                 | NFS_INO_REVAL_FORCED);
1722 
1723         if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1724                 if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1725                         umode_t newmode = inode->i_mode & S_IFMT;
1726                         newmode |= fattr->mode & S_IALLUGO;
1727                         inode->i_mode = newmode;
1728                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1729                 }
1730         } else if (server->caps & NFS_CAP_MODE)
1731                 nfsi->cache_validity |= save_cache_validity &
1732                                 (NFS_INO_INVALID_ATTR
1733                                 | NFS_INO_INVALID_ACCESS
1734                                 | NFS_INO_INVALID_ACL
1735                                 | NFS_INO_REVAL_FORCED);
1736 
1737         if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1738                 if (!uid_eq(inode->i_uid, fattr->uid)) {
1739                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1740                         inode->i_uid = fattr->uid;
1741                 }
1742         } else if (server->caps & NFS_CAP_OWNER)
1743                 nfsi->cache_validity |= save_cache_validity &
1744                                 (NFS_INO_INVALID_ATTR
1745                                 | NFS_INO_INVALID_ACCESS
1746                                 | NFS_INO_INVALID_ACL
1747                                 | NFS_INO_REVAL_FORCED);
1748 
1749         if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
1750                 if (!gid_eq(inode->i_gid, fattr->gid)) {
1751                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1752                         inode->i_gid = fattr->gid;
1753                 }
1754         } else if (server->caps & NFS_CAP_OWNER_GROUP)
1755                 nfsi->cache_validity |= save_cache_validity &
1756                                 (NFS_INO_INVALID_ATTR
1757                                 | NFS_INO_INVALID_ACCESS
1758                                 | NFS_INO_INVALID_ACL
1759                                 | NFS_INO_REVAL_FORCED);
1760 
1761         if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
1762                 if (inode->i_nlink != fattr->nlink) {
1763                         invalid |= NFS_INO_INVALID_ATTR;
1764                         if (S_ISDIR(inode->i_mode))
1765                                 invalid |= NFS_INO_INVALID_DATA;
1766                         set_nlink(inode, fattr->nlink);
1767                 }
1768         } else if (server->caps & NFS_CAP_NLINK)
1769                 nfsi->cache_validity |= save_cache_validity &
1770                                 (NFS_INO_INVALID_ATTR
1771                                 | NFS_INO_REVAL_FORCED);
1772 
1773         if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
1774                 /*
1775                  * report the blocks in 512byte units
1776                  */
1777                 inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1778         }
1779         if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
1780                 inode->i_blocks = fattr->du.nfs2.blocks;
1781 
1782         /* Update attrtimeo value if we're out of the unstable period */
1783         if (invalid & NFS_INO_INVALID_ATTR) {
1784                 nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1785                 nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1786                 nfsi->attrtimeo_timestamp = now;
1787                 /* Set barrier to be more recent than all outstanding updates */
1788                 nfsi->attr_gencount = nfs_inc_attr_generation_counter();
1789         } else {
1790                 if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
1791                         if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
1792                                 nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1793                         nfsi->attrtimeo_timestamp = now;
1794                 }
1795                 /* Set the barrier to be more recent than this fattr */
1796                 if ((long)fattr->gencount - (long)nfsi->attr_gencount > 0)
1797                         nfsi->attr_gencount = fattr->gencount;
1798         }
1799         invalid &= ~NFS_INO_INVALID_ATTR;
1800         /* Don't invalidate the data if we were to blame */
1801         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1802                                 || S_ISLNK(inode->i_mode)))
1803                 invalid &= ~NFS_INO_INVALID_DATA;
1804         if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) ||
1805                         (save_cache_validity & NFS_INO_REVAL_FORCED))
1806                 nfs_set_cache_invalid(inode, invalid);
1807 
1808         return 0;
1809  out_err:
1810         /*
1811          * No need to worry about unhashing the dentry, as the
1812          * lookup validation will know that the inode is bad.
1813          * (But we fall through to invalidate the caches.)
1814          */
1815         nfs_invalidate_inode(inode);
1816         return -ESTALE;
1817 }
1818 
1819 struct inode *nfs_alloc_inode(struct super_block *sb)
1820 {
1821         struct nfs_inode *nfsi;
1822         nfsi = (struct nfs_inode *)kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
1823         if (!nfsi)
1824                 return NULL;
1825         nfsi->flags = 0UL;
1826         nfsi->cache_validity = 0UL;
1827 #if IS_ENABLED(CONFIG_NFS_V4)
1828         nfsi->nfs4_acl = NULL;
1829 #endif /* CONFIG_NFS_V4 */
1830         return &nfsi->vfs_inode;
1831 }
1832 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
1833 
1834 static void nfs_i_callback(struct rcu_head *head)
1835 {
1836         struct inode *inode = container_of(head, struct inode, i_rcu);
1837         kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
1838 }
1839 
1840 void nfs_destroy_inode(struct inode *inode)
1841 {
1842         call_rcu(&inode->i_rcu, nfs_i_callback);
1843 }
1844 EXPORT_SYMBOL_GPL(nfs_destroy_inode);
1845 
1846 static inline void nfs4_init_once(struct nfs_inode *nfsi)
1847 {
1848 #if IS_ENABLED(CONFIG_NFS_V4)
1849         INIT_LIST_HEAD(&nfsi->open_states);
1850         nfsi->delegation = NULL;
1851         init_rwsem(&nfsi->rwsem);
1852         nfsi->layout = NULL;
1853 #endif
1854 }
1855 
1856 static void init_once(void *foo)
1857 {
1858         struct nfs_inode *nfsi = (struct nfs_inode *) foo;
1859 
1860         inode_init_once(&nfsi->vfs_inode);
1861         INIT_LIST_HEAD(&nfsi->open_files);
1862         INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
1863         INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
1864         INIT_LIST_HEAD(&nfsi->commit_info.list);
1865         nfsi->nrequests = 0;
1866         nfsi->commit_info.ncommit = 0;
1867         atomic_set(&nfsi->commit_info.rpcs_out, 0);
1868         atomic_set(&nfsi->silly_count, 1);
1869         INIT_HLIST_HEAD(&nfsi->silly_list);
1870         init_waitqueue_head(&nfsi->waitqueue);
1871         nfs4_init_once(nfsi);
1872 }
1873 
1874 static int __init nfs_init_inodecache(void)
1875 {
1876         nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
1877                                              sizeof(struct nfs_inode),
1878                                              0, (SLAB_RECLAIM_ACCOUNT|
1879                                                 SLAB_MEM_SPREAD),
1880                                              init_once);
1881         if (nfs_inode_cachep == NULL)
1882                 return -ENOMEM;
1883 
1884         return 0;
1885 }
1886 
1887 static void nfs_destroy_inodecache(void)
1888 {
1889         /*
1890          * Make sure all delayed rcu free inodes are flushed before we
1891          * destroy cache.
1892          */
1893         rcu_barrier();
1894         kmem_cache_destroy(nfs_inode_cachep);
1895 }
1896 
1897 struct workqueue_struct *nfsiod_workqueue;
1898 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
1899 
1900 /*
1901  * start up the nfsiod workqueue
1902  */
1903 static int nfsiod_start(void)
1904 {
1905         struct workqueue_struct *wq;
1906         dprintk("RPC:       creating workqueue nfsiod\n");
1907         wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
1908         if (wq == NULL)
1909                 return -ENOMEM;
1910         nfsiod_workqueue = wq;
1911         return 0;
1912 }
1913 
1914 /*
1915  * Destroy the nfsiod workqueue
1916  */
1917 static void nfsiod_stop(void)
1918 {
1919         struct workqueue_struct *wq;
1920 
1921         wq = nfsiod_workqueue;
1922         if (wq == NULL)
1923                 return;
1924         nfsiod_workqueue = NULL;
1925         destroy_workqueue(wq);
1926 }
1927 
1928 int nfs_net_id;
1929 EXPORT_SYMBOL_GPL(nfs_net_id);
1930 
1931 static int nfs_net_init(struct net *net)
1932 {
1933         nfs_clients_init(net);
1934         return nfs_fs_proc_net_init(net);
1935 }
1936 
1937 static void nfs_net_exit(struct net *net)
1938 {
1939         nfs_fs_proc_net_exit(net);
1940         nfs_cleanup_cb_ident_idr(net);
1941 }
1942 
1943 static struct pernet_operations nfs_net_ops = {
1944         .init = nfs_net_init,
1945         .exit = nfs_net_exit,
1946         .id   = &nfs_net_id,
1947         .size = sizeof(struct nfs_net),
1948 };
1949 
1950 /*
1951  * Initialize NFS
1952  */
1953 static int __init init_nfs_fs(void)
1954 {
1955         int err;
1956 
1957         err = register_pernet_subsys(&nfs_net_ops);
1958         if (err < 0)
1959                 goto out9;
1960 
1961         err = nfs_fscache_register();
1962         if (err < 0)
1963                 goto out8;
1964 
1965         err = nfsiod_start();
1966         if (err)
1967                 goto out7;
1968 
1969         err = nfs_fs_proc_init();
1970         if (err)
1971                 goto out6;
1972 
1973         err = nfs_init_nfspagecache();
1974         if (err)
1975                 goto out5;
1976 
1977         err = nfs_init_inodecache();
1978         if (err)
1979                 goto out4;
1980 
1981         err = nfs_init_readpagecache();
1982         if (err)
1983                 goto out3;
1984 
1985         err = nfs_init_writepagecache();
1986         if (err)
1987                 goto out2;
1988 
1989         err = nfs_init_directcache();
1990         if (err)
1991                 goto out1;
1992 
1993 #ifdef CONFIG_PROC_FS
1994         rpc_proc_register(&init_net, &nfs_rpcstat);
1995 #endif
1996         if ((err = register_nfs_fs()) != 0)
1997                 goto out0;
1998 
1999         return 0;
2000 out0:
2001 #ifdef CONFIG_PROC_FS
2002         rpc_proc_unregister(&init_net, "nfs");
2003 #endif
2004         nfs_destroy_directcache();
2005 out1:
2006         nfs_destroy_writepagecache();
2007 out2:
2008         nfs_destroy_readpagecache();
2009 out3:
2010         nfs_destroy_inodecache();
2011 out4:
2012         nfs_destroy_nfspagecache();
2013 out5:
2014         nfs_fs_proc_exit();
2015 out6:
2016         nfsiod_stop();
2017 out7:
2018         nfs_fscache_unregister();
2019 out8:
2020         unregister_pernet_subsys(&nfs_net_ops);
2021 out9:
2022         return err;
2023 }
2024 
2025 static void __exit exit_nfs_fs(void)
2026 {
2027         nfs_destroy_directcache();
2028         nfs_destroy_writepagecache();
2029         nfs_destroy_readpagecache();
2030         nfs_destroy_inodecache();
2031         nfs_destroy_nfspagecache();
2032         nfs_fscache_unregister();
2033         unregister_pernet_subsys(&nfs_net_ops);
2034 #ifdef CONFIG_PROC_FS
2035         rpc_proc_unregister(&init_net, "nfs");
2036 #endif
2037         unregister_nfs_fs();
2038         nfs_fs_proc_exit();
2039         nfsiod_stop();
2040 }
2041 
2042 /* Not quite true; I just maintain it */
2043 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2044 MODULE_LICENSE("GPL");
2045 module_param(enable_ino64, bool, 0644);
2046 
2047 module_init(init_nfs_fs)
2048 module_exit(exit_nfs_fs)
2049 

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