Version:  2.0.40 2.2.26 2.4.37 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 4.1

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

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