Version:  2.0.40 2.2.26 2.4.37 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 4.1 4.2 4.3 4.4 4.5

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 static int nfs_wait_killable(int mode)
 75 {
 76         freezable_schedule_unsafe();
 77         if (signal_pending_state(mode, current))
 78                 return -ERESTARTSYS;
 79         return 0;
 80 }
 81 
 82 int nfs_wait_bit_killable(struct wait_bit_key *key, int mode)
 83 {
 84         return nfs_wait_killable(mode);
 85 }
 86 EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
 87 
 88 int nfs_wait_atomic_killable(atomic_t *p)
 89 {
 90         return nfs_wait_killable(TASK_KILLABLE);
 91 }
 92 
 93 /**
 94  * nfs_compat_user_ino64 - returns the user-visible inode number
 95  * @fileid: 64-bit fileid
 96  *
 97  * This function returns a 32-bit inode number if the boot parameter
 98  * nfs.enable_ino64 is zero.
 99  */
100 u64 nfs_compat_user_ino64(u64 fileid)
101 {
102 #ifdef CONFIG_COMPAT
103         compat_ulong_t ino;
104 #else   
105         unsigned long ino;
106 #endif
107 
108         if (enable_ino64)
109                 return fileid;
110         ino = fileid;
111         if (sizeof(ino) < sizeof(fileid))
112                 ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
113         return ino;
114 }
115 
116 int nfs_drop_inode(struct inode *inode)
117 {
118         return NFS_STALE(inode) || generic_drop_inode(inode);
119 }
120 EXPORT_SYMBOL_GPL(nfs_drop_inode);
121 
122 void nfs_clear_inode(struct inode *inode)
123 {
124         /*
125          * The following should never happen...
126          */
127         WARN_ON_ONCE(nfs_have_writebacks(inode));
128         WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
129         nfs_zap_acl_cache(inode);
130         nfs_access_zap_cache(inode);
131         nfs_fscache_clear_inode(inode);
132 }
133 EXPORT_SYMBOL_GPL(nfs_clear_inode);
134 
135 void nfs_evict_inode(struct inode *inode)
136 {
137         truncate_inode_pages_final(&inode->i_data);
138         clear_inode(inode);
139         nfs_clear_inode(inode);
140 }
141 
142 int nfs_sync_inode(struct inode *inode)
143 {
144         nfs_inode_dio_wait(inode);
145         return nfs_wb_all(inode);
146 }
147 EXPORT_SYMBOL_GPL(nfs_sync_inode);
148 
149 /**
150  * nfs_sync_mapping - helper to flush all mmapped dirty data to disk
151  */
152 int nfs_sync_mapping(struct address_space *mapping)
153 {
154         int ret = 0;
155 
156         if (mapping->nrpages != 0) {
157                 unmap_mapping_range(mapping, 0, 0, 0);
158                 ret = nfs_wb_all(mapping->host);
159         }
160         return ret;
161 }
162 
163 static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
164 {
165         struct nfs_inode *nfsi = NFS_I(inode);
166 
167         if (inode->i_mapping->nrpages == 0)
168                 flags &= ~NFS_INO_INVALID_DATA;
169         nfsi->cache_validity |= flags;
170         if (flags & NFS_INO_INVALID_DATA)
171                 nfs_fscache_invalidate(inode);
172 }
173 
174 /*
175  * Invalidate the local caches
176  */
177 static void nfs_zap_caches_locked(struct inode *inode)
178 {
179         struct nfs_inode *nfsi = NFS_I(inode);
180         int mode = inode->i_mode;
181 
182         nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
183 
184         nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
185         nfsi->attrtimeo_timestamp = jiffies;
186 
187         memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
188         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
189                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
190                                         | NFS_INO_INVALID_DATA
191                                         | NFS_INO_INVALID_ACCESS
192                                         | NFS_INO_INVALID_ACL
193                                         | NFS_INO_REVAL_PAGECACHE);
194         } else
195                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
196                                         | NFS_INO_INVALID_ACCESS
197                                         | NFS_INO_INVALID_ACL
198                                         | NFS_INO_REVAL_PAGECACHE);
199         nfs_zap_label_cache_locked(nfsi);
200 }
201 
202 void nfs_zap_caches(struct inode *inode)
203 {
204         spin_lock(&inode->i_lock);
205         nfs_zap_caches_locked(inode);
206         spin_unlock(&inode->i_lock);
207 }
208 
209 void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
210 {
211         if (mapping->nrpages != 0) {
212                 spin_lock(&inode->i_lock);
213                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
214                 spin_unlock(&inode->i_lock);
215         }
216 }
217 
218 void nfs_zap_acl_cache(struct inode *inode)
219 {
220         void (*clear_acl_cache)(struct inode *);
221 
222         clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
223         if (clear_acl_cache != NULL)
224                 clear_acl_cache(inode);
225         spin_lock(&inode->i_lock);
226         NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
227         spin_unlock(&inode->i_lock);
228 }
229 EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
230 
231 void nfs_invalidate_atime(struct inode *inode)
232 {
233         spin_lock(&inode->i_lock);
234         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
235         spin_unlock(&inode->i_lock);
236 }
237 EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
238 
239 /*
240  * Invalidate, but do not unhash, the inode.
241  * NB: must be called with inode->i_lock held!
242  */
243 static void nfs_invalidate_inode(struct inode *inode)
244 {
245         set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
246         nfs_zap_caches_locked(inode);
247 }
248 
249 struct nfs_find_desc {
250         struct nfs_fh           *fh;
251         struct nfs_fattr        *fattr;
252 };
253 
254 /*
255  * In NFSv3 we can have 64bit inode numbers. In order to support
256  * this, and re-exported directories (also seen in NFSv2)
257  * we are forced to allow 2 different inodes to have the same
258  * i_ino.
259  */
260 static int
261 nfs_find_actor(struct inode *inode, void *opaque)
262 {
263         struct nfs_find_desc    *desc = (struct nfs_find_desc *)opaque;
264         struct nfs_fh           *fh = desc->fh;
265         struct nfs_fattr        *fattr = desc->fattr;
266 
267         if (NFS_FILEID(inode) != fattr->fileid)
268                 return 0;
269         if ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
270                 return 0;
271         if (nfs_compare_fh(NFS_FH(inode), fh))
272                 return 0;
273         if (is_bad_inode(inode) || NFS_STALE(inode))
274                 return 0;
275         return 1;
276 }
277 
278 static int
279 nfs_init_locked(struct inode *inode, void *opaque)
280 {
281         struct nfs_find_desc    *desc = (struct nfs_find_desc *)opaque;
282         struct nfs_fattr        *fattr = desc->fattr;
283 
284         set_nfs_fileid(inode, fattr->fileid);
285         nfs_copy_fh(NFS_FH(inode), desc->fh);
286         return 0;
287 }
288 
289 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
290 static void nfs_clear_label_invalid(struct inode *inode)
291 {
292         spin_lock(&inode->i_lock);
293         NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
294         spin_unlock(&inode->i_lock);
295 }
296 
297 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
298                                         struct nfs4_label *label)
299 {
300         int error;
301 
302         if (label == NULL)
303                 return;
304 
305         if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
306                 error = security_inode_notifysecctx(inode, label->label,
307                                 label->len);
308                 if (error)
309                         printk(KERN_ERR "%s() %s %d "
310                                         "security_inode_notifysecctx() %d\n",
311                                         __func__,
312                                         (char *)label->label,
313                                         label->len, error);
314                 nfs_clear_label_invalid(inode);
315         }
316 }
317 
318 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
319 {
320         struct nfs4_label *label = NULL;
321         int minor_version = server->nfs_client->cl_minorversion;
322 
323         if (minor_version < 2)
324                 return label;
325 
326         if (!(server->caps & NFS_CAP_SECURITY_LABEL))
327                 return label;
328 
329         label = kzalloc(sizeof(struct nfs4_label), flags);
330         if (label == NULL)
331                 return ERR_PTR(-ENOMEM);
332 
333         label->label = kzalloc(NFS4_MAXLABELLEN, flags);
334         if (label->label == NULL) {
335                 kfree(label);
336                 return ERR_PTR(-ENOMEM);
337         }
338         label->len = NFS4_MAXLABELLEN;
339 
340         return label;
341 }
342 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
343 #else
344 void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
345                                         struct nfs4_label *label)
346 {
347 }
348 #endif
349 EXPORT_SYMBOL_GPL(nfs_setsecurity);
350 
351 /*
352  * This is our front-end to iget that looks up inodes by file handle
353  * instead of inode number.
354  */
355 struct inode *
356 nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, struct nfs4_label *label)
357 {
358         struct nfs_find_desc desc = {
359                 .fh     = fh,
360                 .fattr  = fattr
361         };
362         struct inode *inode = ERR_PTR(-ENOENT);
363         unsigned long hash;
364 
365         nfs_attr_check_mountpoint(sb, fattr);
366 
367         if (nfs_attr_use_mounted_on_fileid(fattr))
368                 fattr->fileid = fattr->mounted_on_fileid;
369         else if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
370                 goto out_no_inode;
371         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
372                 goto out_no_inode;
373 
374         hash = nfs_fattr_to_ino_t(fattr);
375 
376         inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
377         if (inode == NULL) {
378                 inode = ERR_PTR(-ENOMEM);
379                 goto out_no_inode;
380         }
381 
382         if (inode->i_state & I_NEW) {
383                 struct nfs_inode *nfsi = NFS_I(inode);
384                 unsigned long now = jiffies;
385 
386                 /* We set i_ino for the few things that still rely on it,
387                  * such as stat(2) */
388                 inode->i_ino = hash;
389 
390                 /* We can't support update_atime(), since the server will reset it */
391                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
392                 inode->i_mode = fattr->mode;
393                 if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
394                                 && nfs_server_capable(inode, NFS_CAP_MODE))
395                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
396                 /* Why so? Because we want revalidate for devices/FIFOs, and
397                  * that's precisely what we have in nfs_file_inode_operations.
398                  */
399                 inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
400                 if (S_ISREG(inode->i_mode)) {
401                         inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
402                         inode->i_data.a_ops = &nfs_file_aops;
403                 } else if (S_ISDIR(inode->i_mode)) {
404                         inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
405                         inode->i_fop = &nfs_dir_operations;
406                         inode->i_data.a_ops = &nfs_dir_aops;
407                         /* Deal with crossing mountpoints */
408                         if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
409                                         fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
410                                 if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
411                                         inode->i_op = &nfs_referral_inode_operations;
412                                 else
413                                         inode->i_op = &nfs_mountpoint_inode_operations;
414                                 inode->i_fop = NULL;
415                                 inode->i_flags |= S_AUTOMOUNT;
416                         }
417                 } else if (S_ISLNK(inode->i_mode)) {
418                         inode->i_op = &nfs_symlink_inode_operations;
419                         inode_nohighmem(inode);
420                 } else
421                         init_special_inode(inode, inode->i_mode, fattr->rdev);
422 
423                 memset(&inode->i_atime, 0, sizeof(inode->i_atime));
424                 memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
425                 memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
426                 inode->i_version = 0;
427                 inode->i_size = 0;
428                 clear_nlink(inode);
429                 inode->i_uid = make_kuid(&init_user_ns, -2);
430                 inode->i_gid = make_kgid(&init_user_ns, -2);
431                 inode->i_blocks = 0;
432                 memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
433                 nfsi->write_io = 0;
434                 nfsi->read_io = 0;
435 
436                 nfsi->read_cache_jiffies = fattr->time_start;
437                 nfsi->attr_gencount = fattr->gencount;
438                 if (fattr->valid & NFS_ATTR_FATTR_ATIME)
439                         inode->i_atime = fattr->atime;
440                 else if (nfs_server_capable(inode, NFS_CAP_ATIME))
441                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
442                 if (fattr->valid & NFS_ATTR_FATTR_MTIME)
443                         inode->i_mtime = fattr->mtime;
444                 else if (nfs_server_capable(inode, NFS_CAP_MTIME))
445                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
446                 if (fattr->valid & NFS_ATTR_FATTR_CTIME)
447                         inode->i_ctime = fattr->ctime;
448                 else if (nfs_server_capable(inode, NFS_CAP_CTIME))
449                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
450                 if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
451                         inode->i_version = fattr->change_attr;
452                 else
453                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
454                                 | NFS_INO_REVAL_PAGECACHE);
455                 if (fattr->valid & NFS_ATTR_FATTR_SIZE)
456                         inode->i_size = nfs_size_to_loff_t(fattr->size);
457                 else
458                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
459                                 | NFS_INO_REVAL_PAGECACHE);
460                 if (fattr->valid & NFS_ATTR_FATTR_NLINK)
461                         set_nlink(inode, fattr->nlink);
462                 else if (nfs_server_capable(inode, NFS_CAP_NLINK))
463                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
464                 if (fattr->valid & NFS_ATTR_FATTR_OWNER)
465                         inode->i_uid = fattr->uid;
466                 else if (nfs_server_capable(inode, NFS_CAP_OWNER))
467                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
468                 if (fattr->valid & NFS_ATTR_FATTR_GROUP)
469                         inode->i_gid = fattr->gid;
470                 else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
471                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
472                 if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
473                         inode->i_blocks = fattr->du.nfs2.blocks;
474                 if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
475                         /*
476                          * report the blocks in 512byte units
477                          */
478                         inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
479                 }
480 
481                 nfs_setsecurity(inode, fattr, label);
482 
483                 nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
484                 nfsi->attrtimeo_timestamp = now;
485                 nfsi->access_cache = RB_ROOT;
486 
487                 nfs_fscache_init_inode(inode);
488 
489                 unlock_new_inode(inode);
490         } else
491                 nfs_refresh_inode(inode, fattr);
492         dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
493                 inode->i_sb->s_id,
494                 (unsigned long long)NFS_FILEID(inode),
495                 nfs_display_fhandle_hash(fh),
496                 atomic_read(&inode->i_count));
497 
498 out:
499         return inode;
500 
501 out_no_inode:
502         dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
503         goto out;
504 }
505 EXPORT_SYMBOL_GPL(nfs_fhget);
506 
507 #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)
508 
509 int
510 nfs_setattr(struct dentry *dentry, struct iattr *attr)
511 {
512         struct inode *inode = d_inode(dentry);
513         struct nfs_fattr *fattr;
514         int error = 0;
515 
516         nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
517 
518         /* skip mode change if it's just for clearing setuid/setgid */
519         if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
520                 attr->ia_valid &= ~ATTR_MODE;
521 
522         if (attr->ia_valid & ATTR_SIZE) {
523                 BUG_ON(!S_ISREG(inode->i_mode));
524 
525                 error = inode_newsize_ok(inode, attr->ia_size);
526                 if (error)
527                         return error;
528 
529                 if (attr->ia_size == i_size_read(inode))
530                         attr->ia_valid &= ~ATTR_SIZE;
531         }
532 
533         /* Optimization: if the end result is no change, don't RPC */
534         attr->ia_valid &= NFS_VALID_ATTRS;
535         if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
536                 return 0;
537 
538         trace_nfs_setattr_enter(inode);
539 
540         /* Write all dirty data */
541         if (S_ISREG(inode->i_mode))
542                 nfs_sync_inode(inode);
543 
544         fattr = nfs_alloc_fattr();
545         if (fattr == NULL) {
546                 error = -ENOMEM;
547                 goto out;
548         }
549 
550         /*
551          * Return any delegations if we're going to change ACLs
552          */
553         if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
554                 NFS_PROTO(inode)->return_delegation(inode);
555         error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
556         if (error == 0)
557                 error = nfs_refresh_inode(inode, fattr);
558         nfs_free_fattr(fattr);
559 out:
560         trace_nfs_setattr_exit(inode, error);
561         return error;
562 }
563 EXPORT_SYMBOL_GPL(nfs_setattr);
564 
565 /**
566  * nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
567  * @inode: inode of the file used
568  * @offset: file offset to start truncating
569  *
570  * This is a copy of the common vmtruncate, but with the locking
571  * corrected to take into account the fact that NFS requires
572  * inode->i_size to be updated under the inode->i_lock.
573  * Note: must be called with inode->i_lock held!
574  */
575 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
576 {
577         int err;
578 
579         err = inode_newsize_ok(inode, offset);
580         if (err)
581                 goto out;
582 
583         i_size_write(inode, offset);
584         /* Optimisation */
585         if (offset == 0)
586                 NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
587 
588         spin_unlock(&inode->i_lock);
589         truncate_pagecache(inode, offset);
590         spin_lock(&inode->i_lock);
591 out:
592         return err;
593 }
594 
595 /**
596  * nfs_setattr_update_inode - Update inode metadata after a setattr call.
597  * @inode: pointer to struct inode
598  * @attr: pointer to struct iattr
599  *
600  * Note: we do this in the *proc.c in order to ensure that
601  *       it works for things like exclusive creates too.
602  */
603 void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr,
604                 struct nfs_fattr *fattr)
605 {
606         /* Barrier: bump the attribute generation count. */
607         nfs_fattr_set_barrier(fattr);
608 
609         spin_lock(&inode->i_lock);
610         NFS_I(inode)->attr_gencount = fattr->gencount;
611         if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
612                 if ((attr->ia_valid & ATTR_MODE) != 0) {
613                         int mode = attr->ia_mode & S_IALLUGO;
614                         mode |= inode->i_mode & ~S_IALLUGO;
615                         inode->i_mode = mode;
616                 }
617                 if ((attr->ia_valid & ATTR_UID) != 0)
618                         inode->i_uid = attr->ia_uid;
619                 if ((attr->ia_valid & ATTR_GID) != 0)
620                         inode->i_gid = attr->ia_gid;
621                 nfs_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
622                                 | NFS_INO_INVALID_ACL);
623         }
624         if ((attr->ia_valid & ATTR_SIZE) != 0) {
625                 nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
626                 nfs_vmtruncate(inode, attr->ia_size);
627         }
628         if (fattr->valid)
629                 nfs_update_inode(inode, fattr);
630         else
631                 NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATTR;
632         spin_unlock(&inode->i_lock);
633 }
634 EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
635 
636 static void nfs_request_parent_use_readdirplus(struct dentry *dentry)
637 {
638         struct dentry *parent;
639 
640         parent = dget_parent(dentry);
641         nfs_force_use_readdirplus(d_inode(parent));
642         dput(parent);
643 }
644 
645 static bool nfs_need_revalidate_inode(struct inode *inode)
646 {
647         if (NFS_I(inode)->cache_validity &
648                         (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
649                 return true;
650         if (nfs_attribute_cache_expired(inode))
651                 return true;
652         return false;
653 }
654 
655 int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
656 {
657         struct inode *inode = d_inode(dentry);
658         int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
659         int err = 0;
660 
661         trace_nfs_getattr_enter(inode);
662         /* Flush out writes to the server in order to update c/mtime.  */
663         if (S_ISREG(inode->i_mode)) {
664                 inode_lock(inode);
665                 err = nfs_sync_inode(inode);
666                 inode_unlock(inode);
667                 if (err)
668                         goto out;
669         }
670 
671         /*
672          * We may force a getattr if the user cares about atime.
673          *
674          * Note that we only have to check the vfsmount flags here:
675          *  - NFS always sets S_NOATIME by so checking it would give a
676          *    bogus result
677          *  - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
678          *    no point in checking those.
679          */
680         if ((mnt->mnt_flags & MNT_NOATIME) ||
681             ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
682                 need_atime = 0;
683 
684         if (need_atime || nfs_need_revalidate_inode(inode)) {
685                 struct nfs_server *server = NFS_SERVER(inode);
686 
687                 if (server->caps & NFS_CAP_READDIRPLUS)
688                         nfs_request_parent_use_readdirplus(dentry);
689                 err = __nfs_revalidate_inode(server, inode);
690         }
691         if (!err) {
692                 generic_fillattr(inode, stat);
693                 stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
694                 if (S_ISDIR(inode->i_mode))
695                         stat->blksize = NFS_SERVER(inode)->dtsize;
696         }
697 out:
698         trace_nfs_getattr_exit(inode, err);
699         return err;
700 }
701 EXPORT_SYMBOL_GPL(nfs_getattr);
702 
703 static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
704 {
705         atomic_set(&l_ctx->count, 1);
706         l_ctx->lockowner.l_owner = current->files;
707         l_ctx->lockowner.l_pid = current->tgid;
708         INIT_LIST_HEAD(&l_ctx->list);
709         atomic_set(&l_ctx->io_count, 0);
710 }
711 
712 static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
713 {
714         struct nfs_lock_context *head = &ctx->lock_context;
715         struct nfs_lock_context *pos = head;
716 
717         do {
718                 if (pos->lockowner.l_owner != current->files)
719                         continue;
720                 if (pos->lockowner.l_pid != current->tgid)
721                         continue;
722                 atomic_inc(&pos->count);
723                 return pos;
724         } while ((pos = list_entry(pos->list.next, typeof(*pos), list)) != head);
725         return NULL;
726 }
727 
728 struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
729 {
730         struct nfs_lock_context *res, *new = NULL;
731         struct inode *inode = d_inode(ctx->dentry);
732 
733         spin_lock(&inode->i_lock);
734         res = __nfs_find_lock_context(ctx);
735         if (res == NULL) {
736                 spin_unlock(&inode->i_lock);
737                 new = kmalloc(sizeof(*new), GFP_KERNEL);
738                 if (new == NULL)
739                         return ERR_PTR(-ENOMEM);
740                 nfs_init_lock_context(new);
741                 spin_lock(&inode->i_lock);
742                 res = __nfs_find_lock_context(ctx);
743                 if (res == NULL) {
744                         list_add_tail(&new->list, &ctx->lock_context.list);
745                         new->open_context = ctx;
746                         res = new;
747                         new = NULL;
748                 }
749         }
750         spin_unlock(&inode->i_lock);
751         kfree(new);
752         return res;
753 }
754 EXPORT_SYMBOL_GPL(nfs_get_lock_context);
755 
756 void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
757 {
758         struct nfs_open_context *ctx = l_ctx->open_context;
759         struct inode *inode = d_inode(ctx->dentry);
760 
761         if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
762                 return;
763         list_del(&l_ctx->list);
764         spin_unlock(&inode->i_lock);
765         kfree(l_ctx);
766 }
767 EXPORT_SYMBOL_GPL(nfs_put_lock_context);
768 
769 /**
770  * nfs_close_context - Common close_context() routine NFSv2/v3
771  * @ctx: pointer to context
772  * @is_sync: is this a synchronous close
773  *
774  * Ensure that the attributes are up to date if we're mounted
775  * with close-to-open semantics and we have cached data that will
776  * need to be revalidated on open.
777  */
778 void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
779 {
780         struct nfs_inode *nfsi;
781         struct inode *inode;
782         struct nfs_server *server;
783 
784         if (!(ctx->mode & FMODE_WRITE))
785                 return;
786         if (!is_sync)
787                 return;
788         inode = d_inode(ctx->dentry);
789         nfsi = NFS_I(inode);
790         if (inode->i_mapping->nrpages == 0)
791                 return;
792         if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
793                 return;
794         if (!list_empty(&nfsi->open_files))
795                 return;
796         server = NFS_SERVER(inode);
797         if (server->flags & NFS_MOUNT_NOCTO)
798                 return;
799         nfs_revalidate_inode(server, inode);
800 }
801 EXPORT_SYMBOL_GPL(nfs_close_context);
802 
803 struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
804 {
805         struct nfs_open_context *ctx;
806         struct rpc_cred *cred = rpc_lookup_cred();
807         if (IS_ERR(cred))
808                 return ERR_CAST(cred);
809 
810         ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
811         if (!ctx) {
812                 put_rpccred(cred);
813                 return ERR_PTR(-ENOMEM);
814         }
815         nfs_sb_active(dentry->d_sb);
816         ctx->dentry = dget(dentry);
817         ctx->cred = cred;
818         ctx->state = NULL;
819         ctx->mode = f_mode;
820         ctx->flags = 0;
821         ctx->error = 0;
822         nfs_init_lock_context(&ctx->lock_context);
823         ctx->lock_context.open_context = ctx;
824         INIT_LIST_HEAD(&ctx->list);
825         ctx->mdsthreshold = NULL;
826         return ctx;
827 }
828 EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
829 
830 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
831 {
832         if (ctx != NULL)
833                 atomic_inc(&ctx->lock_context.count);
834         return ctx;
835 }
836 EXPORT_SYMBOL_GPL(get_nfs_open_context);
837 
838 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
839 {
840         struct inode *inode = d_inode(ctx->dentry);
841         struct super_block *sb = ctx->dentry->d_sb;
842 
843         if (!list_empty(&ctx->list)) {
844                 if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
845                         return;
846                 list_del(&ctx->list);
847                 spin_unlock(&inode->i_lock);
848         } else if (!atomic_dec_and_test(&ctx->lock_context.count))
849                 return;
850         if (inode != NULL)
851                 NFS_PROTO(inode)->close_context(ctx, is_sync);
852         if (ctx->cred != NULL)
853                 put_rpccred(ctx->cred);
854         dput(ctx->dentry);
855         nfs_sb_deactive(sb);
856         kfree(ctx->mdsthreshold);
857         kfree(ctx);
858 }
859 
860 void put_nfs_open_context(struct nfs_open_context *ctx)
861 {
862         __put_nfs_open_context(ctx, 0);
863 }
864 EXPORT_SYMBOL_GPL(put_nfs_open_context);
865 
866 static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
867 {
868         __put_nfs_open_context(ctx, 1);
869 }
870 
871 /*
872  * Ensure that mmap has a recent RPC credential for use when writing out
873  * shared pages
874  */
875 void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
876 {
877         struct inode *inode = d_inode(ctx->dentry);
878         struct nfs_inode *nfsi = NFS_I(inode);
879 
880         spin_lock(&inode->i_lock);
881         list_add(&ctx->list, &nfsi->open_files);
882         spin_unlock(&inode->i_lock);
883 }
884 EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
885 
886 void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
887 {
888         filp->private_data = get_nfs_open_context(ctx);
889         if (list_empty(&ctx->list))
890                 nfs_inode_attach_open_context(ctx);
891 }
892 EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
893 
894 /*
895  * Given an inode, search for an open context with the desired characteristics
896  */
897 struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
898 {
899         struct nfs_inode *nfsi = NFS_I(inode);
900         struct nfs_open_context *pos, *ctx = NULL;
901 
902         spin_lock(&inode->i_lock);
903         list_for_each_entry(pos, &nfsi->open_files, list) {
904                 if (cred != NULL && pos->cred != cred)
905                         continue;
906                 if ((pos->mode & (FMODE_READ|FMODE_WRITE)) != mode)
907                         continue;
908                 ctx = get_nfs_open_context(pos);
909                 break;
910         }
911         spin_unlock(&inode->i_lock);
912         return ctx;
913 }
914 
915 void nfs_file_clear_open_context(struct file *filp)
916 {
917         struct nfs_open_context *ctx = nfs_file_open_context(filp);
918 
919         if (ctx) {
920                 struct inode *inode = d_inode(ctx->dentry);
921 
922                 /*
923                  * We fatal error on write before. Try to writeback
924                  * every page again.
925                  */
926                 if (ctx->error < 0)
927                         invalidate_inode_pages2(inode->i_mapping);
928                 filp->private_data = NULL;
929                 spin_lock(&inode->i_lock);
930                 list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
931                 spin_unlock(&inode->i_lock);
932                 put_nfs_open_context_sync(ctx);
933         }
934 }
935 
936 /*
937  * These allocate and release file read/write context information.
938  */
939 int nfs_open(struct inode *inode, struct file *filp)
940 {
941         struct nfs_open_context *ctx;
942 
943         ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
944         if (IS_ERR(ctx))
945                 return PTR_ERR(ctx);
946         nfs_file_set_open_context(filp, ctx);
947         put_nfs_open_context(ctx);
948         nfs_fscache_open_file(inode, filp);
949         return 0;
950 }
951 
952 /*
953  * This function is called whenever some part of NFS notices that
954  * the cached attributes have to be refreshed.
955  */
956 int
957 __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
958 {
959         int              status = -ESTALE;
960         struct nfs4_label *label = NULL;
961         struct nfs_fattr *fattr = NULL;
962         struct nfs_inode *nfsi = NFS_I(inode);
963 
964         dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
965                 inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
966 
967         trace_nfs_revalidate_inode_enter(inode);
968 
969         if (is_bad_inode(inode))
970                 goto out;
971         if (NFS_STALE(inode))
972                 goto out;
973 
974         status = -ENOMEM;
975         fattr = nfs_alloc_fattr();
976         if (fattr == NULL)
977                 goto out;
978 
979         nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
980 
981         label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
982         if (IS_ERR(label)) {
983                 status = PTR_ERR(label);
984                 goto out;
985         }
986 
987         status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, label);
988         if (status != 0) {
989                 dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
990                          inode->i_sb->s_id,
991                          (unsigned long long)NFS_FILEID(inode), status);
992                 if (status == -ESTALE) {
993                         nfs_zap_caches(inode);
994                         if (!S_ISDIR(inode->i_mode))
995                                 set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
996                 }
997                 goto err_out;
998         }
999 
1000         status = nfs_refresh_inode(inode, fattr);
1001         if (status) {
1002                 dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
1003                          inode->i_sb->s_id,
1004                          (unsigned long long)NFS_FILEID(inode), status);
1005                 goto err_out;
1006         }
1007 
1008         if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
1009                 nfs_zap_acl_cache(inode);
1010 
1011         nfs_setsecurity(inode, fattr, label);
1012 
1013         dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
1014                 inode->i_sb->s_id,
1015                 (unsigned long long)NFS_FILEID(inode));
1016 
1017 err_out:
1018         nfs4_label_free(label);
1019 out:
1020         nfs_free_fattr(fattr);
1021         trace_nfs_revalidate_inode_exit(inode, status);
1022         return status;
1023 }
1024 
1025 int nfs_attribute_timeout(struct inode *inode)
1026 {
1027         struct nfs_inode *nfsi = NFS_I(inode);
1028 
1029         return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
1030 }
1031 
1032 int nfs_attribute_cache_expired(struct inode *inode)
1033 {
1034         if (nfs_have_delegated_attributes(inode))
1035                 return 0;
1036         return nfs_attribute_timeout(inode);
1037 }
1038 
1039 /**
1040  * nfs_revalidate_inode - Revalidate the inode attributes
1041  * @server - pointer to nfs_server struct
1042  * @inode - pointer to inode struct
1043  *
1044  * Updates inode attribute information by retrieving the data from the server.
1045  */
1046 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
1047 {
1048         if (!nfs_need_revalidate_inode(inode))
1049                 return NFS_STALE(inode) ? -ESTALE : 0;
1050         return __nfs_revalidate_inode(server, inode);
1051 }
1052 EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
1053 
1054 int nfs_revalidate_inode_rcu(struct nfs_server *server, struct inode *inode)
1055 {
1056         if (!(NFS_I(inode)->cache_validity &
1057                         (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
1058                         && !nfs_attribute_cache_expired(inode))
1059                 return NFS_STALE(inode) ? -ESTALE : 0;
1060         return -ECHILD;
1061 }
1062 
1063 static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
1064 {
1065         struct nfs_inode *nfsi = NFS_I(inode);
1066         int ret;
1067 
1068         if (mapping->nrpages != 0) {
1069                 if (S_ISREG(inode->i_mode)) {
1070                         unmap_mapping_range(mapping, 0, 0, 0);
1071                         ret = nfs_sync_mapping(mapping);
1072                         if (ret < 0)
1073                                 return ret;
1074                 }
1075                 ret = invalidate_inode_pages2(mapping);
1076                 if (ret < 0)
1077                         return ret;
1078         }
1079         if (S_ISDIR(inode->i_mode)) {
1080                 spin_lock(&inode->i_lock);
1081                 memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
1082                 spin_unlock(&inode->i_lock);
1083         }
1084         nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
1085         nfs_fscache_wait_on_invalidate(inode);
1086 
1087         dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
1088                         inode->i_sb->s_id,
1089                         (unsigned long long)NFS_FILEID(inode));
1090         return 0;
1091 }
1092 
1093 static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
1094 {
1095         if (nfs_have_delegated_attributes(inode))
1096                 return false;
1097         return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
1098                 || nfs_attribute_timeout(inode)
1099                 || NFS_STALE(inode);
1100 }
1101 
1102 int nfs_revalidate_mapping_rcu(struct inode *inode)
1103 {
1104         struct nfs_inode *nfsi = NFS_I(inode);
1105         unsigned long *bitlock = &nfsi->flags;
1106         int ret = 0;
1107 
1108         if (IS_SWAPFILE(inode))
1109                 goto out;
1110         if (nfs_mapping_need_revalidate_inode(inode)) {
1111                 ret = -ECHILD;
1112                 goto out;
1113         }
1114         spin_lock(&inode->i_lock);
1115         if (test_bit(NFS_INO_INVALIDATING, bitlock) ||
1116             (nfsi->cache_validity & NFS_INO_INVALID_DATA))
1117                 ret = -ECHILD;
1118         spin_unlock(&inode->i_lock);
1119 out:
1120         return ret;
1121 }
1122 
1123 /**
1124  * __nfs_revalidate_mapping - Revalidate the pagecache
1125  * @inode - pointer to host inode
1126  * @mapping - pointer to mapping
1127  * @may_lock - take inode->i_mutex?
1128  */
1129 static int __nfs_revalidate_mapping(struct inode *inode,
1130                 struct address_space *mapping,
1131                 bool may_lock)
1132 {
1133         struct nfs_inode *nfsi = NFS_I(inode);
1134         unsigned long *bitlock = &nfsi->flags;
1135         int ret = 0;
1136 
1137         /* swapfiles are not supposed to be shared. */
1138         if (IS_SWAPFILE(inode))
1139                 goto out;
1140 
1141         if (nfs_mapping_need_revalidate_inode(inode)) {
1142                 ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
1143                 if (ret < 0)
1144                         goto out;
1145         }
1146 
1147         /*
1148          * We must clear NFS_INO_INVALID_DATA first to ensure that
1149          * invalidations that come in while we're shooting down the mappings
1150          * are respected. But, that leaves a race window where one revalidator
1151          * can clear the flag, and then another checks it before the mapping
1152          * gets invalidated. Fix that by serializing access to this part of
1153          * the function.
1154          *
1155          * At the same time, we need to allow other tasks to see whether we
1156          * might be in the middle of invalidating the pages, so we only set
1157          * the bit lock here if it looks like we're going to be doing that.
1158          */
1159         for (;;) {
1160                 ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
1161                                          nfs_wait_bit_killable, TASK_KILLABLE);
1162                 if (ret)
1163                         goto out;
1164                 spin_lock(&inode->i_lock);
1165                 if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
1166                         spin_unlock(&inode->i_lock);
1167                         continue;
1168                 }
1169                 if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
1170                         break;
1171                 spin_unlock(&inode->i_lock);
1172                 goto out;
1173         }
1174 
1175         set_bit(NFS_INO_INVALIDATING, bitlock);
1176         smp_wmb();
1177         nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
1178         spin_unlock(&inode->i_lock);
1179         trace_nfs_invalidate_mapping_enter(inode);
1180         if (may_lock) {
1181                 inode_lock(inode);
1182                 ret = nfs_invalidate_mapping(inode, mapping);
1183                 inode_unlock(inode);
1184         } else
1185                 ret = nfs_invalidate_mapping(inode, mapping);
1186         trace_nfs_invalidate_mapping_exit(inode, ret);
1187 
1188         clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
1189         smp_mb__after_atomic();
1190         wake_up_bit(bitlock, NFS_INO_INVALIDATING);
1191 out:
1192         return ret;
1193 }
1194 
1195 /**
1196  * nfs_revalidate_mapping - Revalidate the pagecache
1197  * @inode - pointer to host inode
1198  * @mapping - pointer to mapping
1199  */
1200 int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
1201 {
1202         return __nfs_revalidate_mapping(inode, mapping, false);
1203 }
1204 
1205 /**
1206  * nfs_revalidate_mapping_protected - Revalidate the pagecache
1207  * @inode - pointer to host inode
1208  * @mapping - pointer to mapping
1209  *
1210  * Differs from nfs_revalidate_mapping() in that it grabs the inode->i_mutex
1211  * while invalidating the mapping.
1212  */
1213 int nfs_revalidate_mapping_protected(struct inode *inode, struct address_space *mapping)
1214 {
1215         return __nfs_revalidate_mapping(inode, mapping, true);
1216 }
1217 
1218 static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1219 {
1220         struct nfs_inode *nfsi = NFS_I(inode);
1221         unsigned long ret = 0;
1222 
1223         if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
1224                         && (fattr->valid & NFS_ATTR_FATTR_CHANGE)
1225                         && inode->i_version == fattr->pre_change_attr) {
1226                 inode->i_version = fattr->change_attr;
1227                 if (S_ISDIR(inode->i_mode))
1228                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1229                 ret |= NFS_INO_INVALID_ATTR;
1230         }
1231         /* If we have atomic WCC data, we may update some attributes */
1232         if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
1233                         && (fattr->valid & NFS_ATTR_FATTR_CTIME)
1234                         && timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
1235                 memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1236                 ret |= NFS_INO_INVALID_ATTR;
1237         }
1238 
1239         if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
1240                         && (fattr->valid & NFS_ATTR_FATTR_MTIME)
1241                         && timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
1242                 memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1243                 if (S_ISDIR(inode->i_mode))
1244                         nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
1245                 ret |= NFS_INO_INVALID_ATTR;
1246         }
1247         if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
1248                         && (fattr->valid & NFS_ATTR_FATTR_SIZE)
1249                         && i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
1250                         && nfsi->nrequests == 0) {
1251                 i_size_write(inode, nfs_size_to_loff_t(fattr->size));
1252                 ret |= NFS_INO_INVALID_ATTR;
1253         }
1254 
1255         return ret;
1256 }
1257 
1258 /**
1259  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
1260  * @inode - pointer to inode
1261  * @fattr - updated attributes
1262  *
1263  * Verifies the attribute cache. If we have just changed the attributes,
1264  * so that fattr carries weak cache consistency data, then it may
1265  * also update the ctime/mtime/change_attribute.
1266  */
1267 static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
1268 {
1269         struct nfs_inode *nfsi = NFS_I(inode);
1270         loff_t cur_size, new_isize;
1271         unsigned long invalid = 0;
1272 
1273 
1274         if (nfs_have_delegated_attributes(inode))
1275                 return 0;
1276         /* Has the inode gone and changed behind our back? */
1277         if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
1278                 return -EIO;
1279         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
1280                 return -EIO;
1281 
1282         if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1283                         inode->i_version != fattr->change_attr)
1284                 invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1285 
1286         /* Verify a few of the more important attributes */
1287         if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
1288                 invalid |= NFS_INO_INVALID_ATTR;
1289 
1290         if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1291                 cur_size = i_size_read(inode);
1292                 new_isize = nfs_size_to_loff_t(fattr->size);
1293                 if (cur_size != new_isize)
1294                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1295         }
1296         if (nfsi->nrequests != 0)
1297                 invalid &= ~NFS_INO_REVAL_PAGECACHE;
1298 
1299         /* Have any file permissions changed? */
1300         if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
1301                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1302         if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && !uid_eq(inode->i_uid, fattr->uid))
1303                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1304         if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && !gid_eq(inode->i_gid, fattr->gid))
1305                 invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
1306 
1307         /* Has the link count changed? */
1308         if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
1309                 invalid |= NFS_INO_INVALID_ATTR;
1310 
1311         if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
1312                 invalid |= NFS_INO_INVALID_ATIME;
1313 
1314         if (invalid != 0)
1315                 nfs_set_cache_invalid(inode, invalid);
1316 
1317         nfsi->read_cache_jiffies = fattr->time_start;
1318         return 0;
1319 }
1320 
1321 static atomic_long_t nfs_attr_generation_counter;
1322 
1323 static unsigned long nfs_read_attr_generation_counter(void)
1324 {
1325         return atomic_long_read(&nfs_attr_generation_counter);
1326 }
1327 
1328 unsigned long nfs_inc_attr_generation_counter(void)
1329 {
1330         return atomic_long_inc_return(&nfs_attr_generation_counter);
1331 }
1332 EXPORT_SYMBOL_GPL(nfs_inc_attr_generation_counter);
1333 
1334 void nfs_fattr_init(struct nfs_fattr *fattr)
1335 {
1336         fattr->valid = 0;
1337         fattr->time_start = jiffies;
1338         fattr->gencount = nfs_inc_attr_generation_counter();
1339         fattr->owner_name = NULL;
1340         fattr->group_name = NULL;
1341 }
1342 EXPORT_SYMBOL_GPL(nfs_fattr_init);
1343 
1344 /**
1345  * nfs_fattr_set_barrier
1346  * @fattr: attributes
1347  *
1348  * Used to set a barrier after an attribute was updated. This
1349  * barrier ensures that older attributes from RPC calls that may
1350  * have raced with our update cannot clobber these new values.
1351  * Note that you are still responsible for ensuring that other
1352  * operations which change the attribute on the server do not
1353  * collide.
1354  */
1355 void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
1356 {
1357         fattr->gencount = nfs_inc_attr_generation_counter();
1358 }
1359 
1360 struct nfs_fattr *nfs_alloc_fattr(void)
1361 {
1362         struct nfs_fattr *fattr;
1363 
1364         fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
1365         if (fattr != NULL)
1366                 nfs_fattr_init(fattr);
1367         return fattr;
1368 }
1369 EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
1370 
1371 struct nfs_fh *nfs_alloc_fhandle(void)
1372 {
1373         struct nfs_fh *fh;
1374 
1375         fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
1376         if (fh != NULL)
1377                 fh->size = 0;
1378         return fh;
1379 }
1380 EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
1381 
1382 #ifdef NFS_DEBUG
1383 /*
1384  * _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
1385  *                             in the same way that wireshark does
1386  *
1387  * @fh: file handle
1388  *
1389  * For debugging only.
1390  */
1391 u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
1392 {
1393         /* wireshark uses 32-bit AUTODIN crc and does a bitwise
1394          * not on the result */
1395         return nfs_fhandle_hash(fh);
1396 }
1397 EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
1398 
1399 /*
1400  * _nfs_display_fhandle - display an NFS file handle on the console
1401  *
1402  * @fh: file handle to display
1403  * @caption: display caption
1404  *
1405  * For debugging only.
1406  */
1407 void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
1408 {
1409         unsigned short i;
1410 
1411         if (fh == NULL || fh->size == 0) {
1412                 printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
1413                 return;
1414         }
1415 
1416         printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
1417                caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
1418         for (i = 0; i < fh->size; i += 16) {
1419                 __be32 *pos = (__be32 *)&fh->data[i];
1420 
1421                 switch ((fh->size - i - 1) >> 2) {
1422                 case 0:
1423                         printk(KERN_DEFAULT " %08x\n",
1424                                 be32_to_cpup(pos));
1425                         break;
1426                 case 1:
1427                         printk(KERN_DEFAULT " %08x %08x\n",
1428                                 be32_to_cpup(pos), be32_to_cpup(pos + 1));
1429                         break;
1430                 case 2:
1431                         printk(KERN_DEFAULT " %08x %08x %08x\n",
1432                                 be32_to_cpup(pos), be32_to_cpup(pos + 1),
1433                                 be32_to_cpup(pos + 2));
1434                         break;
1435                 default:
1436                         printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
1437                                 be32_to_cpup(pos), be32_to_cpup(pos + 1),
1438                                 be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
1439                 }
1440         }
1441 }
1442 EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
1443 #endif
1444 
1445 /**
1446  * nfs_inode_attrs_need_update - check if the inode attributes need updating
1447  * @inode - pointer to inode
1448  * @fattr - attributes
1449  *
1450  * Attempt to divine whether or not an RPC call reply carrying stale
1451  * attributes got scheduled after another call carrying updated ones.
1452  *
1453  * To do so, the function first assumes that a more recent ctime means
1454  * that the attributes in fattr are newer, however it also attempt to
1455  * catch the case where ctime either didn't change, or went backwards
1456  * (if someone reset the clock on the server) by looking at whether
1457  * or not this RPC call was started after the inode was last updated.
1458  * Note also the check for wraparound of 'attr_gencount'
1459  *
1460  * The function returns 'true' if it thinks the attributes in 'fattr' are
1461  * more recent than the ones cached in the inode.
1462  *
1463  */
1464 static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
1465 {
1466         const struct nfs_inode *nfsi = NFS_I(inode);
1467 
1468         return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
1469                 ((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
1470 }
1471 
1472 /*
1473  * Don't trust the change_attribute, mtime, ctime or size if
1474  * a pnfs LAYOUTCOMMIT is outstanding
1475  */
1476 static void nfs_inode_attrs_handle_layoutcommit(struct inode *inode,
1477                 struct nfs_fattr *fattr)
1478 {
1479         if (pnfs_layoutcommit_outstanding(inode))
1480                 fattr->valid &= ~(NFS_ATTR_FATTR_CHANGE |
1481                                 NFS_ATTR_FATTR_MTIME |
1482                                 NFS_ATTR_FATTR_CTIME |
1483                                 NFS_ATTR_FATTR_SIZE);
1484 }
1485 
1486 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1487 {
1488         int ret;
1489 
1490         trace_nfs_refresh_inode_enter(inode);
1491 
1492         nfs_inode_attrs_handle_layoutcommit(inode, fattr);
1493 
1494         if (nfs_inode_attrs_need_update(inode, fattr))
1495                 ret = nfs_update_inode(inode, fattr);
1496         else
1497                 ret = nfs_check_inode_attributes(inode, fattr);
1498 
1499         trace_nfs_refresh_inode_exit(inode, ret);
1500         return ret;
1501 }
1502 
1503 /**
1504  * nfs_refresh_inode - try to update the inode attribute cache
1505  * @inode - pointer to inode
1506  * @fattr - updated attributes
1507  *
1508  * Check that an RPC call that returned attributes has not overlapped with
1509  * other recent updates of the inode metadata, then decide whether it is
1510  * safe to do a full update of the inode attributes, or whether just to
1511  * call nfs_check_inode_attributes.
1512  */
1513 int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
1514 {
1515         int status;
1516 
1517         if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1518                 return 0;
1519         spin_lock(&inode->i_lock);
1520         status = nfs_refresh_inode_locked(inode, fattr);
1521         spin_unlock(&inode->i_lock);
1522 
1523         return status;
1524 }
1525 EXPORT_SYMBOL_GPL(nfs_refresh_inode);
1526 
1527 static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
1528 {
1529         unsigned long invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
1530 
1531         /*
1532          * Don't revalidate the pagecache if we hold a delegation, but do
1533          * force an attribute update
1534          */
1535         if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
1536                 invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_FORCED;
1537 
1538         if (S_ISDIR(inode->i_mode))
1539                 invalid |= NFS_INO_INVALID_DATA;
1540         nfs_set_cache_invalid(inode, invalid);
1541         if ((fattr->valid & NFS_ATTR_FATTR) == 0)
1542                 return 0;
1543         return nfs_refresh_inode_locked(inode, fattr);
1544 }
1545 
1546 /**
1547  * nfs_post_op_update_inode - try to update the inode attribute cache
1548  * @inode - pointer to inode
1549  * @fattr - updated attributes
1550  *
1551  * After an operation that has changed the inode metadata, mark the
1552  * attribute cache as being invalid, then try to update it.
1553  *
1554  * NB: if the server didn't return any post op attributes, this
1555  * function will force the retrieval of attributes before the next
1556  * NFS request.  Thus it should be used only for operations that
1557  * are expected to change one or more attributes, to avoid
1558  * unnecessary NFS requests and trips through nfs_update_inode().
1559  */
1560 int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1561 {
1562         int status;
1563 
1564         spin_lock(&inode->i_lock);
1565         nfs_fattr_set_barrier(fattr);
1566         status = nfs_post_op_update_inode_locked(inode, fattr);
1567         spin_unlock(&inode->i_lock);
1568 
1569         return status;
1570 }
1571 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
1572 
1573 /**
1574  * nfs_post_op_update_inode_force_wcc_locked - update the inode attribute cache
1575  * @inode - pointer to inode
1576  * @fattr - updated attributes
1577  *
1578  * After an operation that has changed the inode metadata, mark the
1579  * attribute cache as being invalid, then try to update it. Fake up
1580  * weak cache consistency data, if none exist.
1581  *
1582  * This function is mainly designed to be used by the ->write_done() functions.
1583  */
1584 int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
1585 {
1586         int status;
1587 
1588         /* Don't do a WCC update if these attributes are already stale */
1589         if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
1590                         !nfs_inode_attrs_need_update(inode, fattr)) {
1591                 fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
1592                                 | NFS_ATTR_FATTR_PRESIZE
1593                                 | NFS_ATTR_FATTR_PREMTIME
1594                                 | NFS_ATTR_FATTR_PRECTIME);
1595                 goto out_noforce;
1596         }
1597         if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
1598                         (fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
1599                 fattr->pre_change_attr = inode->i_version;
1600                 fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
1601         }
1602         if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
1603                         (fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
1604                 memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
1605                 fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
1606         }
1607         if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
1608                         (fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
1609                 memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
1610                 fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
1611         }
1612         if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
1613                         (fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
1614                 fattr->pre_size = i_size_read(inode);
1615                 fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
1616         }
1617 out_noforce:
1618         status = nfs_post_op_update_inode_locked(inode, fattr);
1619         return status;
1620 }
1621 
1622 /**
1623  * nfs_post_op_update_inode_force_wcc - try to update the inode attribute cache
1624  * @inode - pointer to inode
1625  * @fattr - updated attributes
1626  *
1627  * After an operation that has changed the inode metadata, mark the
1628  * attribute cache as being invalid, then try to update it. Fake up
1629  * weak cache consistency data, if none exist.
1630  *
1631  * This function is mainly designed to be used by the ->write_done() functions.
1632  */
1633 int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
1634 {
1635         int status;
1636 
1637         spin_lock(&inode->i_lock);
1638         nfs_fattr_set_barrier(fattr);
1639         status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
1640         spin_unlock(&inode->i_lock);
1641         return status;
1642 }
1643 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
1644 
1645 
1646 static inline bool nfs_fileid_valid(struct nfs_inode *nfsi,
1647                                     struct nfs_fattr *fattr)
1648 {
1649         bool ret1 = true, ret2 = true;
1650 
1651         if (fattr->valid & NFS_ATTR_FATTR_FILEID)
1652                 ret1 = (nfsi->fileid == fattr->fileid);
1653         if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
1654                 ret2 = (nfsi->fileid == fattr->mounted_on_fileid);
1655         return ret1 || ret2;
1656 }
1657 
1658 /*
1659  * Many nfs protocol calls return the new file attributes after
1660  * an operation.  Here we update the inode to reflect the state
1661  * of the server's inode.
1662  *
1663  * This is a bit tricky because we have to make sure all dirty pages
1664  * have been sent off to the server before calling invalidate_inode_pages.
1665  * To make sure no other process adds more write requests while we try
1666  * our best to flush them, we make them sleep during the attribute refresh.
1667  *
1668  * A very similar scenario holds for the dir cache.
1669  */
1670 static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
1671 {
1672         struct nfs_server *server;
1673         struct nfs_inode *nfsi = NFS_I(inode);
1674         loff_t cur_isize, new_isize;
1675         unsigned long invalid = 0;
1676         unsigned long now = jiffies;
1677         unsigned long save_cache_validity;
1678         bool cache_revalidated = true;
1679 
1680         dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%x)\n",
1681                         __func__, inode->i_sb->s_id, inode->i_ino,
1682                         nfs_display_fhandle_hash(NFS_FH(inode)),
1683                         atomic_read(&inode->i_count), fattr->valid);
1684 
1685         if (!nfs_fileid_valid(nfsi, fattr)) {
1686                 printk(KERN_ERR "NFS: server %s error: fileid changed\n"
1687                         "fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
1688                         NFS_SERVER(inode)->nfs_client->cl_hostname,
1689                         inode->i_sb->s_id, (long long)nfsi->fileid,
1690                         (long long)fattr->fileid);
1691                 goto out_err;
1692         }
1693 
1694         /*
1695          * Make sure the inode's type hasn't changed.
1696          */
1697         if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
1698                 /*
1699                 * Big trouble! The inode has become a different object.
1700                 */
1701                 printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
1702                                 __func__, inode->i_ino, inode->i_mode, fattr->mode);
1703                 goto out_err;
1704         }
1705 
1706         server = NFS_SERVER(inode);
1707         /* Update the fsid? */
1708         if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
1709                         !nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
1710                         !IS_AUTOMOUNT(inode))
1711                 server->fsid = fattr->fsid;
1712 
1713         /*
1714          * Update the read time so we don't revalidate too often.
1715          */
1716         nfsi->read_cache_jiffies = fattr->time_start;
1717 
1718         save_cache_validity = nfsi->cache_validity;
1719         nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
1720                         | NFS_INO_INVALID_ATIME
1721                         | NFS_INO_REVAL_FORCED
1722                         | NFS_INO_REVAL_PAGECACHE);
1723 
1724         /* Do atomic weak cache consistency updates */
1725         invalid |= nfs_wcc_update_inode(inode, fattr);
1726 
1727         /* More cache consistency checks */
1728         if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
1729                 if (inode->i_version != fattr->change_attr) {
1730                         dprintk("NFS: change_attr change on server for file %s/%ld\n",
1731                                         inode->i_sb->s_id, inode->i_ino);
1732                         invalid |= NFS_INO_INVALID_ATTR
1733                                 | NFS_INO_INVALID_DATA
1734                                 | NFS_INO_INVALID_ACCESS
1735                                 | NFS_INO_INVALID_ACL;
1736                         if (S_ISDIR(inode->i_mode))
1737                                 nfs_force_lookup_revalidate(inode);
1738                         inode->i_version = fattr->change_attr;
1739                 }
1740         } else {
1741                 nfsi->cache_validity |= save_cache_validity;
1742                 cache_revalidated = false;
1743         }
1744 
1745         if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
1746                 memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
1747         } else if (server->caps & NFS_CAP_MTIME) {
1748                 nfsi->cache_validity |= save_cache_validity &
1749                                 (NFS_INO_INVALID_ATTR
1750                                 | NFS_INO_REVAL_FORCED);
1751                 cache_revalidated = false;
1752         }
1753 
1754         if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
1755                 memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
1756         } else if (server->caps & NFS_CAP_CTIME) {
1757                 nfsi->cache_validity |= save_cache_validity &
1758                                 (NFS_INO_INVALID_ATTR
1759                                 | NFS_INO_REVAL_FORCED);
1760                 cache_revalidated = false;
1761         }
1762 
1763         /* Check if our cached file size is stale */
1764         if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
1765                 new_isize = nfs_size_to_loff_t(fattr->size);
1766                 cur_isize = i_size_read(inode);
1767                 if (new_isize != cur_isize) {
1768                         /* Do we perhaps have any outstanding writes, or has
1769                          * the file grown beyond our last write? */
1770                         if ((nfsi->nrequests == 0) || new_isize > cur_isize) {
1771                                 i_size_write(inode, new_isize);
1772                                 invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
1773                         }
1774                         dprintk("NFS: isize change on server for file %s/%ld "
1775                                         "(%Ld to %Ld)\n",
1776                                         inode->i_sb->s_id,
1777                                         inode->i_ino,
1778                                         (long long)cur_isize,
1779                                         (long long)new_isize);
1780                 }
1781         } else {
1782                 nfsi->cache_validity |= save_cache_validity &
1783                                 (NFS_INO_INVALID_ATTR
1784                                 | NFS_INO_REVAL_PAGECACHE
1785                                 | NFS_INO_REVAL_FORCED);
1786                 cache_revalidated = false;
1787         }
1788 
1789 
1790         if (fattr->valid & NFS_ATTR_FATTR_ATIME)
1791                 memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
1792         else if (server->caps & NFS_CAP_ATIME) {
1793                 nfsi->cache_validity |= save_cache_validity &
1794                                 (NFS_INO_INVALID_ATIME
1795                                 | NFS_INO_REVAL_FORCED);
1796                 cache_revalidated = false;
1797         }
1798 
1799         if (fattr->valid & NFS_ATTR_FATTR_MODE) {
1800                 if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
1801                         umode_t newmode = inode->i_mode & S_IFMT;
1802                         newmode |= fattr->mode & S_IALLUGO;
1803                         inode->i_mode = newmode;
1804                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1805                 }
1806         } else if (server->caps & NFS_CAP_MODE) {
1807                 nfsi->cache_validity |= save_cache_validity &
1808                                 (NFS_INO_INVALID_ATTR
1809                                 | NFS_INO_INVALID_ACCESS
1810                                 | NFS_INO_INVALID_ACL
1811                                 | NFS_INO_REVAL_FORCED);
1812                 cache_revalidated = false;
1813         }
1814 
1815         if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
1816                 if (!uid_eq(inode->i_uid, fattr->uid)) {
1817                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1818                         inode->i_uid = fattr->uid;
1819                 }
1820         } else if (server->caps & NFS_CAP_OWNER) {
1821                 nfsi->cache_validity |= save_cache_validity &
1822                                 (NFS_INO_INVALID_ATTR
1823                                 | NFS_INO_INVALID_ACCESS
1824                                 | NFS_INO_INVALID_ACL
1825                                 | NFS_INO_REVAL_FORCED);
1826                 cache_revalidated = false;
1827         }
1828 
1829         if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
1830                 if (!gid_eq(inode->i_gid, fattr->gid)) {
1831                         invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
1832                         inode->i_gid = fattr->gid;
1833                 }
1834         } else if (server->caps & NFS_CAP_OWNER_GROUP) {
1835                 nfsi->cache_validity |= save_cache_validity &
1836                                 (NFS_INO_INVALID_ATTR
1837                                 | NFS_INO_INVALID_ACCESS
1838                                 | NFS_INO_INVALID_ACL
1839                                 | NFS_INO_REVAL_FORCED);
1840                 cache_revalidated = false;
1841         }
1842 
1843         if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
1844                 if (inode->i_nlink != fattr->nlink) {
1845                         invalid |= NFS_INO_INVALID_ATTR;
1846                         if (S_ISDIR(inode->i_mode))
1847                                 invalid |= NFS_INO_INVALID_DATA;
1848                         set_nlink(inode, fattr->nlink);
1849                 }
1850         } else if (server->caps & NFS_CAP_NLINK) {
1851                 nfsi->cache_validity |= save_cache_validity &
1852                                 (NFS_INO_INVALID_ATTR
1853                                 | NFS_INO_REVAL_FORCED);
1854                 cache_revalidated = false;
1855         }
1856 
1857         if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
1858                 /*
1859                  * report the blocks in 512byte units
1860                  */
1861                 inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
1862         } else if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
1863                 inode->i_blocks = fattr->du.nfs2.blocks;
1864         else
1865                 cache_revalidated = false;
1866 
1867         /* Update attrtimeo value if we're out of the unstable period */
1868         if (invalid & NFS_INO_INVALID_ATTR) {
1869                 nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
1870                 nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
1871                 nfsi->attrtimeo_timestamp = now;
1872                 /* Set barrier to be more recent than all outstanding updates */
1873                 nfsi->attr_gencount = nfs_inc_attr_generation_counter();
1874         } else {
1875                 if (cache_revalidated) {
1876                         if (!time_in_range_open(now, nfsi->attrtimeo_timestamp,
1877                                 nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
1878                                 nfsi->attrtimeo <<= 1;
1879                                 if (nfsi->attrtimeo > NFS_MAXATTRTIMEO(inode))
1880                                         nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
1881                         }
1882                         nfsi->attrtimeo_timestamp = now;
1883                 }
1884                 /* Set the barrier to be more recent than this fattr */
1885                 if ((long)fattr->gencount - (long)nfsi->attr_gencount > 0)
1886                         nfsi->attr_gencount = fattr->gencount;
1887         }
1888 
1889         /* Don't declare attrcache up to date if there were no attrs! */
1890         if (cache_revalidated)
1891                 invalid &= ~NFS_INO_INVALID_ATTR;
1892 
1893         /* Don't invalidate the data if we were to blame */
1894         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1895                                 || S_ISLNK(inode->i_mode)))
1896                 invalid &= ~NFS_INO_INVALID_DATA;
1897         if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) ||
1898                         (save_cache_validity & NFS_INO_REVAL_FORCED))
1899                 nfs_set_cache_invalid(inode, invalid);
1900 
1901         return 0;
1902  out_err:
1903         /*
1904          * No need to worry about unhashing the dentry, as the
1905          * lookup validation will know that the inode is bad.
1906          * (But we fall through to invalidate the caches.)
1907          */
1908         nfs_invalidate_inode(inode);
1909         return -ESTALE;
1910 }
1911 
1912 struct inode *nfs_alloc_inode(struct super_block *sb)
1913 {
1914         struct nfs_inode *nfsi;
1915         nfsi = kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
1916         if (!nfsi)
1917                 return NULL;
1918         nfsi->flags = 0UL;
1919         nfsi->cache_validity = 0UL;
1920 #if IS_ENABLED(CONFIG_NFS_V4)
1921         nfsi->nfs4_acl = NULL;
1922 #endif /* CONFIG_NFS_V4 */
1923         return &nfsi->vfs_inode;
1924 }
1925 EXPORT_SYMBOL_GPL(nfs_alloc_inode);
1926 
1927 static void nfs_i_callback(struct rcu_head *head)
1928 {
1929         struct inode *inode = container_of(head, struct inode, i_rcu);
1930         kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
1931 }
1932 
1933 void nfs_destroy_inode(struct inode *inode)
1934 {
1935         call_rcu(&inode->i_rcu, nfs_i_callback);
1936 }
1937 EXPORT_SYMBOL_GPL(nfs_destroy_inode);
1938 
1939 static inline void nfs4_init_once(struct nfs_inode *nfsi)
1940 {
1941 #if IS_ENABLED(CONFIG_NFS_V4)
1942         INIT_LIST_HEAD(&nfsi->open_states);
1943         nfsi->delegation = NULL;
1944         init_rwsem(&nfsi->rwsem);
1945         nfsi->layout = NULL;
1946 #endif
1947 }
1948 
1949 static void init_once(void *foo)
1950 {
1951         struct nfs_inode *nfsi = (struct nfs_inode *) foo;
1952 
1953         inode_init_once(&nfsi->vfs_inode);
1954         INIT_LIST_HEAD(&nfsi->open_files);
1955         INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
1956         INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
1957         INIT_LIST_HEAD(&nfsi->commit_info.list);
1958         nfsi->nrequests = 0;
1959         nfsi->commit_info.ncommit = 0;
1960         atomic_set(&nfsi->commit_info.rpcs_out, 0);
1961         atomic_set(&nfsi->silly_count, 1);
1962         INIT_HLIST_HEAD(&nfsi->silly_list);
1963         init_waitqueue_head(&nfsi->waitqueue);
1964         nfs4_init_once(nfsi);
1965 }
1966 
1967 static int __init nfs_init_inodecache(void)
1968 {
1969         nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
1970                                              sizeof(struct nfs_inode),
1971                                              0, (SLAB_RECLAIM_ACCOUNT|
1972                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1973                                              init_once);
1974         if (nfs_inode_cachep == NULL)
1975                 return -ENOMEM;
1976 
1977         return 0;
1978 }
1979 
1980 static void nfs_destroy_inodecache(void)
1981 {
1982         /*
1983          * Make sure all delayed rcu free inodes are flushed before we
1984          * destroy cache.
1985          */
1986         rcu_barrier();
1987         kmem_cache_destroy(nfs_inode_cachep);
1988 }
1989 
1990 struct workqueue_struct *nfsiod_workqueue;
1991 EXPORT_SYMBOL_GPL(nfsiod_workqueue);
1992 
1993 /*
1994  * start up the nfsiod workqueue
1995  */
1996 static int nfsiod_start(void)
1997 {
1998         struct workqueue_struct *wq;
1999         dprintk("RPC:       creating workqueue nfsiod\n");
2000         wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
2001         if (wq == NULL)
2002                 return -ENOMEM;
2003         nfsiod_workqueue = wq;
2004         return 0;
2005 }
2006 
2007 /*
2008  * Destroy the nfsiod workqueue
2009  */
2010 static void nfsiod_stop(void)
2011 {
2012         struct workqueue_struct *wq;
2013 
2014         wq = nfsiod_workqueue;
2015         if (wq == NULL)
2016                 return;
2017         nfsiod_workqueue = NULL;
2018         destroy_workqueue(wq);
2019 }
2020 
2021 int nfs_net_id;
2022 EXPORT_SYMBOL_GPL(nfs_net_id);
2023 
2024 static int nfs_net_init(struct net *net)
2025 {
2026         nfs_clients_init(net);
2027         return nfs_fs_proc_net_init(net);
2028 }
2029 
2030 static void nfs_net_exit(struct net *net)
2031 {
2032         nfs_fs_proc_net_exit(net);
2033         nfs_cleanup_cb_ident_idr(net);
2034 }
2035 
2036 static struct pernet_operations nfs_net_ops = {
2037         .init = nfs_net_init,
2038         .exit = nfs_net_exit,
2039         .id   = &nfs_net_id,
2040         .size = sizeof(struct nfs_net),
2041 };
2042 
2043 /*
2044  * Initialize NFS
2045  */
2046 static int __init init_nfs_fs(void)
2047 {
2048         int err;
2049 
2050         err = register_pernet_subsys(&nfs_net_ops);
2051         if (err < 0)
2052                 goto out9;
2053 
2054         err = nfs_fscache_register();
2055         if (err < 0)
2056                 goto out8;
2057 
2058         err = nfsiod_start();
2059         if (err)
2060                 goto out7;
2061 
2062         err = nfs_fs_proc_init();
2063         if (err)
2064                 goto out6;
2065 
2066         err = nfs_init_nfspagecache();
2067         if (err)
2068                 goto out5;
2069 
2070         err = nfs_init_inodecache();
2071         if (err)
2072                 goto out4;
2073 
2074         err = nfs_init_readpagecache();
2075         if (err)
2076                 goto out3;
2077 
2078         err = nfs_init_writepagecache();
2079         if (err)
2080                 goto out2;
2081 
2082         err = nfs_init_directcache();
2083         if (err)
2084                 goto out1;
2085 
2086         rpc_proc_register(&init_net, &nfs_rpcstat);
2087 
2088         err = register_nfs_fs();
2089         if (err)
2090                 goto out0;
2091 
2092         return 0;
2093 out0:
2094         rpc_proc_unregister(&init_net, "nfs");
2095         nfs_destroy_directcache();
2096 out1:
2097         nfs_destroy_writepagecache();
2098 out2:
2099         nfs_destroy_readpagecache();
2100 out3:
2101         nfs_destroy_inodecache();
2102 out4:
2103         nfs_destroy_nfspagecache();
2104 out5:
2105         nfs_fs_proc_exit();
2106 out6:
2107         nfsiod_stop();
2108 out7:
2109         nfs_fscache_unregister();
2110 out8:
2111         unregister_pernet_subsys(&nfs_net_ops);
2112 out9:
2113         return err;
2114 }
2115 
2116 static void __exit exit_nfs_fs(void)
2117 {
2118         nfs_destroy_directcache();
2119         nfs_destroy_writepagecache();
2120         nfs_destroy_readpagecache();
2121         nfs_destroy_inodecache();
2122         nfs_destroy_nfspagecache();
2123         nfs_fscache_unregister();
2124         unregister_pernet_subsys(&nfs_net_ops);
2125         rpc_proc_unregister(&init_net, "nfs");
2126         unregister_nfs_fs();
2127         nfs_fs_proc_exit();
2128         nfsiod_stop();
2129 }
2130 
2131 /* Not quite true; I just maintain it */
2132 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
2133 MODULE_LICENSE("GPL");
2134 module_param(enable_ino64, bool, 0644);
2135 
2136 module_init(init_nfs_fs)
2137 module_exit(exit_nfs_fs)
2138 

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us