Version:  2.0.40 2.2.26 2.4.37 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 4.6 4.7

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

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