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-rw-r--r--fs/nfsd/vfs.c1859
1 files changed, 1859 insertions, 0 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
new file mode 100644
index 000000000000..e3e9d217236e
--- /dev/null
+++ b/fs/nfsd/vfs.c
@@ -0,0 +1,1859 @@
1#define MSNFS /* HACK HACK */
2/*
3 * linux/fs/nfsd/vfs.c
4 *
5 * File operations used by nfsd. Some of these have been ripped from
6 * other parts of the kernel because they weren't exported, others
7 * are partial duplicates with added or changed functionality.
8 *
9 * Note that several functions dget() the dentry upon which they want
10 * to act, most notably those that create directory entries. Response
11 * dentry's are dput()'d if necessary in the release callback.
12 * So if you notice code paths that apparently fail to dput() the
13 * dentry, don't worry--they have been taken care of.
14 *
15 * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de>
16 * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp>
17 */
18
19#include <linux/config.h>
20#include <linux/string.h>
21#include <linux/time.h>
22#include <linux/errno.h>
23#include <linux/fs.h>
24#include <linux/file.h>
25#include <linux/mount.h>
26#include <linux/major.h>
27#include <linux/ext2_fs.h>
28#include <linux/proc_fs.h>
29#include <linux/stat.h>
30#include <linux/fcntl.h>
31#include <linux/net.h>
32#include <linux/unistd.h>
33#include <linux/slab.h>
34#include <linux/pagemap.h>
35#include <linux/in.h>
36#include <linux/module.h>
37#include <linux/namei.h>
38#include <linux/vfs.h>
39#include <linux/delay.h>
40#include <linux/sunrpc/svc.h>
41#include <linux/nfsd/nfsd.h>
42#ifdef CONFIG_NFSD_V3
43#include <linux/nfs3.h>
44#include <linux/nfsd/xdr3.h>
45#endif /* CONFIG_NFSD_V3 */
46#include <linux/nfsd/nfsfh.h>
47#include <linux/quotaops.h>
48#include <linux/dnotify.h>
49#ifdef CONFIG_NFSD_V4
50#include <linux/posix_acl.h>
51#include <linux/posix_acl_xattr.h>
52#include <linux/xattr_acl.h>
53#include <linux/xattr.h>
54#include <linux/nfs4.h>
55#include <linux/nfs4_acl.h>
56#include <linux/nfsd_idmap.h>
57#include <linux/security.h>
58#endif /* CONFIG_NFSD_V4 */
59
60#include <asm/uaccess.h>
61
62#define NFSDDBG_FACILITY NFSDDBG_FILEOP
63#define NFSD_PARANOIA
64
65
66/* We must ignore files (but only files) which might have mandatory
67 * locks on them because there is no way to know if the accesser has
68 * the lock.
69 */
70#define IS_ISMNDLK(i) (S_ISREG((i)->i_mode) && MANDATORY_LOCK(i))
71
72/*
73 * This is a cache of readahead params that help us choose the proper
74 * readahead strategy. Initially, we set all readahead parameters to 0
75 * and let the VFS handle things.
76 * If you increase the number of cached files very much, you'll need to
77 * add a hash table here.
78 */
79struct raparms {
80 struct raparms *p_next;
81 unsigned int p_count;
82 ino_t p_ino;
83 dev_t p_dev;
84 int p_set;
85 struct file_ra_state p_ra;
86};
87
88static struct raparms * raparml;
89static struct raparms * raparm_cache;
90
91/*
92 * Called from nfsd_lookup and encode_dirent. Check if we have crossed
93 * a mount point.
94 * Returns -EAGAIN leaving *dpp and *expp unchanged,
95 * or nfs_ok having possibly changed *dpp and *expp
96 */
97int
98nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
99 struct svc_export **expp)
100{
101 struct svc_export *exp = *expp, *exp2 = NULL;
102 struct dentry *dentry = *dpp;
103 struct vfsmount *mnt = mntget(exp->ex_mnt);
104 struct dentry *mounts = dget(dentry);
105 int err = nfs_ok;
106
107 while (follow_down(&mnt,&mounts)&&d_mountpoint(mounts));
108
109 exp2 = exp_get_by_name(exp->ex_client, mnt, mounts, &rqstp->rq_chandle);
110 if (IS_ERR(exp2)) {
111 err = PTR_ERR(exp2);
112 dput(mounts);
113 mntput(mnt);
114 goto out;
115 }
116 if (exp2 && ((exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2))) {
117 /* successfully crossed mount point */
118 exp_put(exp);
119 *expp = exp2;
120 dput(dentry);
121 *dpp = mounts;
122 } else {
123 if (exp2) exp_put(exp2);
124 dput(mounts);
125 }
126 mntput(mnt);
127out:
128 return err;
129}
130
131/*
132 * Look up one component of a pathname.
133 * N.B. After this call _both_ fhp and resfh need an fh_put
134 *
135 * If the lookup would cross a mountpoint, and the mounted filesystem
136 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
137 * accepted as it stands and the mounted directory is
138 * returned. Otherwise the covered directory is returned.
139 * NOTE: this mountpoint crossing is not supported properly by all
140 * clients and is explicitly disallowed for NFSv3
141 * NeilBrown <neilb@cse.unsw.edu.au>
142 */
143int
144nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
145 int len, struct svc_fh *resfh)
146{
147 struct svc_export *exp;
148 struct dentry *dparent;
149 struct dentry *dentry;
150 int err;
151
152 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
153
154 /* Obtain dentry and export. */
155 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_EXEC);
156 if (err)
157 return err;
158
159 dparent = fhp->fh_dentry;
160 exp = fhp->fh_export;
161 exp_get(exp);
162
163 err = nfserr_acces;
164
165 /* Lookup the name, but don't follow links */
166 if (isdotent(name, len)) {
167 if (len==1)
168 dentry = dget(dparent);
169 else if (dparent != exp->ex_dentry) {
170 dentry = dget_parent(dparent);
171 } else if (!EX_NOHIDE(exp))
172 dentry = dget(dparent); /* .. == . just like at / */
173 else {
174 /* checking mountpoint crossing is very different when stepping up */
175 struct svc_export *exp2 = NULL;
176 struct dentry *dp;
177 struct vfsmount *mnt = mntget(exp->ex_mnt);
178 dentry = dget(dparent);
179 while(dentry == mnt->mnt_root && follow_up(&mnt, &dentry))
180 ;
181 dp = dget_parent(dentry);
182 dput(dentry);
183 dentry = dp;
184
185 exp2 = exp_parent(exp->ex_client, mnt, dentry,
186 &rqstp->rq_chandle);
187 if (IS_ERR(exp2)) {
188 err = PTR_ERR(exp2);
189 dput(dentry);
190 mntput(mnt);
191 goto out_nfserr;
192 }
193 if (!exp2) {
194 dput(dentry);
195 dentry = dget(dparent);
196 } else {
197 exp_put(exp);
198 exp = exp2;
199 }
200 mntput(mnt);
201 }
202 } else {
203 fh_lock(fhp);
204 dentry = lookup_one_len(name, dparent, len);
205 err = PTR_ERR(dentry);
206 if (IS_ERR(dentry))
207 goto out_nfserr;
208 /*
209 * check if we have crossed a mount point ...
210 */
211 if (d_mountpoint(dentry)) {
212 if ((err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
213 dput(dentry);
214 goto out_nfserr;
215 }
216 }
217 }
218 /*
219 * Note: we compose the file handle now, but as the
220 * dentry may be negative, it may need to be updated.
221 */
222 err = fh_compose(resfh, exp, dentry, fhp);
223 if (!err && !dentry->d_inode)
224 err = nfserr_noent;
225 dput(dentry);
226out:
227 exp_put(exp);
228 return err;
229
230out_nfserr:
231 err = nfserrno(err);
232 goto out;
233}
234
235/*
236 * Set various file attributes.
237 * N.B. After this call fhp needs an fh_put
238 */
239int
240nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
241 int check_guard, time_t guardtime)
242{
243 struct dentry *dentry;
244 struct inode *inode;
245 int accmode = MAY_SATTR;
246 int ftype = 0;
247 int imode;
248 int err;
249 int size_change = 0;
250
251 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
252 accmode |= MAY_WRITE|MAY_OWNER_OVERRIDE;
253 if (iap->ia_valid & ATTR_SIZE)
254 ftype = S_IFREG;
255
256 /* Get inode */
257 err = fh_verify(rqstp, fhp, ftype, accmode);
258 if (err || !iap->ia_valid)
259 goto out;
260
261 dentry = fhp->fh_dentry;
262 inode = dentry->d_inode;
263
264 /* NFSv2 does not differentiate between "set-[ac]time-to-now"
265 * which only requires access, and "set-[ac]time-to-X" which
266 * requires ownership.
267 * So if it looks like it might be "set both to the same time which
268 * is close to now", and if inode_change_ok fails, then we
269 * convert to "set to now" instead of "set to explicit time"
270 *
271 * We only call inode_change_ok as the last test as technically
272 * it is not an interface that we should be using. It is only
273 * valid if the filesystem does not define it's own i_op->setattr.
274 */
275#define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
276#define MAX_TOUCH_TIME_ERROR (30*60)
277 if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET
278 && iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec
279 ) {
280 /* Looks probable. Now just make sure time is in the right ballpark.
281 * Solaris, at least, doesn't seem to care what the time request is.
282 * We require it be within 30 minutes of now.
283 */
284 time_t delta = iap->ia_atime.tv_sec - get_seconds();
285 if (delta<0) delta = -delta;
286 if (delta < MAX_TOUCH_TIME_ERROR &&
287 inode_change_ok(inode, iap) != 0) {
288 /* turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME
289 * this will cause notify_change to set these times to "now"
290 */
291 iap->ia_valid &= ~BOTH_TIME_SET;
292 }
293 }
294
295 /* The size case is special. It changes the file as well as the attributes. */
296 if (iap->ia_valid & ATTR_SIZE) {
297 if (iap->ia_size < inode->i_size) {
298 err = nfsd_permission(fhp->fh_export, dentry, MAY_TRUNC|MAY_OWNER_OVERRIDE);
299 if (err)
300 goto out;
301 }
302
303 /*
304 * If we are changing the size of the file, then
305 * we need to break all leases.
306 */
307 err = break_lease(inode, FMODE_WRITE | O_NONBLOCK);
308 if (err == -EWOULDBLOCK)
309 err = -ETIMEDOUT;
310 if (err) /* ENOMEM or EWOULDBLOCK */
311 goto out_nfserr;
312
313 err = get_write_access(inode);
314 if (err)
315 goto out_nfserr;
316
317 size_change = 1;
318 err = locks_verify_truncate(inode, NULL, iap->ia_size);
319 if (err) {
320 put_write_access(inode);
321 goto out_nfserr;
322 }
323 DQUOT_INIT(inode);
324 }
325
326 imode = inode->i_mode;
327 if (iap->ia_valid & ATTR_MODE) {
328 iap->ia_mode &= S_IALLUGO;
329 imode = iap->ia_mode |= (imode & ~S_IALLUGO);
330 }
331
332 /* Revoke setuid/setgid bit on chown/chgrp */
333 if ((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid)
334 iap->ia_valid |= ATTR_KILL_SUID;
335 if ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid)
336 iap->ia_valid |= ATTR_KILL_SGID;
337
338 /* Change the attributes. */
339
340 iap->ia_valid |= ATTR_CTIME;
341
342 err = nfserr_notsync;
343 if (!check_guard || guardtime == inode->i_ctime.tv_sec) {
344 fh_lock(fhp);
345 err = notify_change(dentry, iap);
346 err = nfserrno(err);
347 fh_unlock(fhp);
348 }
349 if (size_change)
350 put_write_access(inode);
351 if (!err)
352 if (EX_ISSYNC(fhp->fh_export))
353 write_inode_now(inode, 1);
354out:
355 return err;
356
357out_nfserr:
358 err = nfserrno(err);
359 goto out;
360}
361
362#if defined(CONFIG_NFSD_V4)
363
364static int
365set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key)
366{
367 int len;
368 size_t buflen;
369 char *buf = NULL;
370 int error = 0;
371 struct inode *inode = dentry->d_inode;
372
373 buflen = posix_acl_xattr_size(pacl->a_count);
374 buf = kmalloc(buflen, GFP_KERNEL);
375 error = -ENOMEM;
376 if (buf == NULL)
377 goto out;
378
379 len = posix_acl_to_xattr(pacl, buf, buflen);
380 if (len < 0) {
381 error = len;
382 goto out;
383 }
384
385 error = -EOPNOTSUPP;
386 if (inode->i_op && inode->i_op->setxattr) {
387 down(&inode->i_sem);
388 security_inode_setxattr(dentry, key, buf, len, 0);
389 error = inode->i_op->setxattr(dentry, key, buf, len, 0);
390 if (!error)
391 security_inode_post_setxattr(dentry, key, buf, len, 0);
392 up(&inode->i_sem);
393 }
394out:
395 kfree(buf);
396 return error;
397}
398
399int
400nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
401 struct nfs4_acl *acl)
402{
403 int error;
404 struct dentry *dentry;
405 struct inode *inode;
406 struct posix_acl *pacl = NULL, *dpacl = NULL;
407 unsigned int flags = 0;
408
409 /* Get inode */
410 error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, MAY_SATTR);
411 if (error)
412 goto out;
413
414 dentry = fhp->fh_dentry;
415 inode = dentry->d_inode;
416 if (S_ISDIR(inode->i_mode))
417 flags = NFS4_ACL_DIR;
418
419 error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags);
420 if (error == -EINVAL) {
421 error = nfserr_attrnotsupp;
422 goto out;
423 } else if (error < 0)
424 goto out_nfserr;
425
426 if (pacl) {
427 error = set_nfsv4_acl_one(dentry, pacl, XATTR_NAME_ACL_ACCESS);
428 if (error < 0)
429 goto out_nfserr;
430 }
431
432 if (dpacl) {
433 error = set_nfsv4_acl_one(dentry, dpacl, XATTR_NAME_ACL_DEFAULT);
434 if (error < 0)
435 goto out_nfserr;
436 }
437
438 error = nfs_ok;
439
440out:
441 posix_acl_release(pacl);
442 posix_acl_release(dpacl);
443 return (error);
444out_nfserr:
445 error = nfserrno(error);
446 goto out;
447}
448
449static struct posix_acl *
450_get_posix_acl(struct dentry *dentry, char *key)
451{
452 struct inode *inode = dentry->d_inode;
453 char *buf = NULL;
454 int buflen, error = 0;
455 struct posix_acl *pacl = NULL;
456
457 error = -EOPNOTSUPP;
458 if (inode->i_op == NULL)
459 goto out_err;
460 if (inode->i_op->getxattr == NULL)
461 goto out_err;
462
463 error = security_inode_getxattr(dentry, key);
464 if (error)
465 goto out_err;
466
467 buflen = inode->i_op->getxattr(dentry, key, NULL, 0);
468 if (buflen <= 0) {
469 error = buflen < 0 ? buflen : -ENODATA;
470 goto out_err;
471 }
472
473 buf = kmalloc(buflen, GFP_KERNEL);
474 if (buf == NULL) {
475 error = -ENOMEM;
476 goto out_err;
477 }
478
479 error = inode->i_op->getxattr(dentry, key, buf, buflen);
480 if (error < 0)
481 goto out_err;
482
483 pacl = posix_acl_from_xattr(buf, buflen);
484 out:
485 kfree(buf);
486 return pacl;
487 out_err:
488 pacl = ERR_PTR(error);
489 goto out;
490}
491
492int
493nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl)
494{
495 struct inode *inode = dentry->d_inode;
496 int error = 0;
497 struct posix_acl *pacl = NULL, *dpacl = NULL;
498 unsigned int flags = 0;
499
500 pacl = _get_posix_acl(dentry, XATTR_NAME_ACL_ACCESS);
501 if (IS_ERR(pacl) && PTR_ERR(pacl) == -ENODATA)
502 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
503 if (IS_ERR(pacl)) {
504 error = PTR_ERR(pacl);
505 pacl = NULL;
506 goto out;
507 }
508
509 if (S_ISDIR(inode->i_mode)) {
510 dpacl = _get_posix_acl(dentry, XATTR_NAME_ACL_DEFAULT);
511 if (IS_ERR(dpacl) && PTR_ERR(dpacl) == -ENODATA)
512 dpacl = NULL;
513 else if (IS_ERR(dpacl)) {
514 error = PTR_ERR(dpacl);
515 dpacl = NULL;
516 goto out;
517 }
518 flags = NFS4_ACL_DIR;
519 }
520
521 *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags);
522 if (IS_ERR(*acl)) {
523 error = PTR_ERR(*acl);
524 *acl = NULL;
525 }
526 out:
527 posix_acl_release(pacl);
528 posix_acl_release(dpacl);
529 return error;
530}
531
532#endif /* defined(CONFIG_NFS_V4) */
533
534#ifdef CONFIG_NFSD_V3
535/*
536 * Check server access rights to a file system object
537 */
538struct accessmap {
539 u32 access;
540 int how;
541};
542static struct accessmap nfs3_regaccess[] = {
543 { NFS3_ACCESS_READ, MAY_READ },
544 { NFS3_ACCESS_EXECUTE, MAY_EXEC },
545 { NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_TRUNC },
546 { NFS3_ACCESS_EXTEND, MAY_WRITE },
547
548 { 0, 0 }
549};
550
551static struct accessmap nfs3_diraccess[] = {
552 { NFS3_ACCESS_READ, MAY_READ },
553 { NFS3_ACCESS_LOOKUP, MAY_EXEC },
554 { NFS3_ACCESS_MODIFY, MAY_EXEC|MAY_WRITE|MAY_TRUNC },
555 { NFS3_ACCESS_EXTEND, MAY_EXEC|MAY_WRITE },
556 { NFS3_ACCESS_DELETE, MAY_REMOVE },
557
558 { 0, 0 }
559};
560
561static struct accessmap nfs3_anyaccess[] = {
562 /* Some clients - Solaris 2.6 at least, make an access call
563 * to the server to check for access for things like /dev/null
564 * (which really, the server doesn't care about). So
565 * We provide simple access checking for them, looking
566 * mainly at mode bits, and we make sure to ignore read-only
567 * filesystem checks
568 */
569 { NFS3_ACCESS_READ, MAY_READ },
570 { NFS3_ACCESS_EXECUTE, MAY_EXEC },
571 { NFS3_ACCESS_MODIFY, MAY_WRITE|MAY_LOCAL_ACCESS },
572 { NFS3_ACCESS_EXTEND, MAY_WRITE|MAY_LOCAL_ACCESS },
573
574 { 0, 0 }
575};
576
577int
578nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported)
579{
580 struct accessmap *map;
581 struct svc_export *export;
582 struct dentry *dentry;
583 u32 query, result = 0, sresult = 0;
584 unsigned int error;
585
586 error = fh_verify(rqstp, fhp, 0, MAY_NOP);
587 if (error)
588 goto out;
589
590 export = fhp->fh_export;
591 dentry = fhp->fh_dentry;
592
593 if (S_ISREG(dentry->d_inode->i_mode))
594 map = nfs3_regaccess;
595 else if (S_ISDIR(dentry->d_inode->i_mode))
596 map = nfs3_diraccess;
597 else
598 map = nfs3_anyaccess;
599
600
601 query = *access;
602 for (; map->access; map++) {
603 if (map->access & query) {
604 unsigned int err2;
605
606 sresult |= map->access;
607
608 err2 = nfsd_permission(export, dentry, map->how);
609 switch (err2) {
610 case nfs_ok:
611 result |= map->access;
612 break;
613
614 /* the following error codes just mean the access was not allowed,
615 * rather than an error occurred */
616 case nfserr_rofs:
617 case nfserr_acces:
618 case nfserr_perm:
619 /* simply don't "or" in the access bit. */
620 break;
621 default:
622 error = err2;
623 goto out;
624 }
625 }
626 }
627 *access = result;
628 if (supported)
629 *supported = sresult;
630
631 out:
632 return error;
633}
634#endif /* CONFIG_NFSD_V3 */
635
636
637
638/*
639 * Open an existing file or directory.
640 * The access argument indicates the type of open (read/write/lock)
641 * N.B. After this call fhp needs an fh_put
642 */
643int
644nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
645 int access, struct file **filp)
646{
647 struct dentry *dentry;
648 struct inode *inode;
649 int flags = O_RDONLY|O_LARGEFILE, err;
650
651 /*
652 * If we get here, then the client has already done an "open",
653 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
654 * in case a chmod has now revoked permission.
655 */
656 err = fh_verify(rqstp, fhp, type, access | MAY_OWNER_OVERRIDE);
657 if (err)
658 goto out;
659
660 dentry = fhp->fh_dentry;
661 inode = dentry->d_inode;
662
663 /* Disallow write access to files with the append-only bit set
664 * or any access when mandatory locking enabled
665 */
666 err = nfserr_perm;
667 if (IS_APPEND(inode) && (access & MAY_WRITE))
668 goto out;
669 if (IS_ISMNDLK(inode))
670 goto out;
671
672 if (!inode->i_fop)
673 goto out;
674
675 /*
676 * Check to see if there are any leases on this file.
677 * This may block while leases are broken.
678 */
679 err = break_lease(inode, O_NONBLOCK | ((access & MAY_WRITE) ? FMODE_WRITE : 0));
680 if (err == -EWOULDBLOCK)
681 err = -ETIMEDOUT;
682 if (err) /* NOMEM or WOULDBLOCK */
683 goto out_nfserr;
684
685 if (access & MAY_WRITE) {
686 flags = O_WRONLY|O_LARGEFILE;
687
688 DQUOT_INIT(inode);
689 }
690 *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_mnt), flags);
691 if (IS_ERR(*filp))
692 err = PTR_ERR(*filp);
693out_nfserr:
694 if (err)
695 err = nfserrno(err);
696out:
697 return err;
698}
699
700/*
701 * Close a file.
702 */
703void
704nfsd_close(struct file *filp)
705{
706 fput(filp);
707}
708
709/*
710 * Sync a file
711 * As this calls fsync (not fdatasync) there is no need for a write_inode
712 * after it.
713 */
714static inline void nfsd_dosync(struct file *filp, struct dentry *dp,
715 struct file_operations *fop)
716{
717 struct inode *inode = dp->d_inode;
718 int (*fsync) (struct file *, struct dentry *, int);
719
720 filemap_fdatawrite(inode->i_mapping);
721 if (fop && (fsync = fop->fsync))
722 fsync(filp, dp, 0);
723 filemap_fdatawait(inode->i_mapping);
724}
725
726
727static void
728nfsd_sync(struct file *filp)
729{
730 struct inode *inode = filp->f_dentry->d_inode;
731 dprintk("nfsd: sync file %s\n", filp->f_dentry->d_name.name);
732 down(&inode->i_sem);
733 nfsd_dosync(filp, filp->f_dentry, filp->f_op);
734 up(&inode->i_sem);
735}
736
737static void
738nfsd_sync_dir(struct dentry *dp)
739{
740 nfsd_dosync(NULL, dp, dp->d_inode->i_fop);
741}
742
743/*
744 * Obtain the readahead parameters for the file
745 * specified by (dev, ino).
746 */
747static DEFINE_SPINLOCK(ra_lock);
748
749static inline struct raparms *
750nfsd_get_raparms(dev_t dev, ino_t ino)
751{
752 struct raparms *ra, **rap, **frap = NULL;
753 int depth = 0;
754
755 spin_lock(&ra_lock);
756 for (rap = &raparm_cache; (ra = *rap); rap = &ra->p_next) {
757 if (ra->p_ino == ino && ra->p_dev == dev)
758 goto found;
759 depth++;
760 if (ra->p_count == 0)
761 frap = rap;
762 }
763 depth = nfsdstats.ra_size*11/10;
764 if (!frap) {
765 spin_unlock(&ra_lock);
766 return NULL;
767 }
768 rap = frap;
769 ra = *frap;
770 ra->p_dev = dev;
771 ra->p_ino = ino;
772 ra->p_set = 0;
773found:
774 if (rap != &raparm_cache) {
775 *rap = ra->p_next;
776 ra->p_next = raparm_cache;
777 raparm_cache = ra;
778 }
779 ra->p_count++;
780 nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++;
781 spin_unlock(&ra_lock);
782 return ra;
783}
784
785/*
786 * Grab and keep cached pages assosiated with a file in the svc_rqst
787 * so that they can be passed to the netowork sendmsg/sendpage routines
788 * directrly. They will be released after the sending has completed.
789 */
790static int
791nfsd_read_actor(read_descriptor_t *desc, struct page *page, unsigned long offset , unsigned long size)
792{
793 unsigned long count = desc->count;
794 struct svc_rqst *rqstp = desc->arg.data;
795
796 if (size > count)
797 size = count;
798
799 if (rqstp->rq_res.page_len == 0) {
800 get_page(page);
801 rqstp->rq_respages[rqstp->rq_resused++] = page;
802 rqstp->rq_res.page_base = offset;
803 rqstp->rq_res.page_len = size;
804 } else if (page != rqstp->rq_respages[rqstp->rq_resused-1]) {
805 get_page(page);
806 rqstp->rq_respages[rqstp->rq_resused++] = page;
807 rqstp->rq_res.page_len += size;
808 } else {
809 rqstp->rq_res.page_len += size;
810 }
811
812 desc->count = count - size;
813 desc->written += size;
814 return size;
815}
816
817static inline int
818nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
819 loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
820{
821 struct inode *inode;
822 struct raparms *ra;
823 mm_segment_t oldfs;
824 int err;
825
826 err = nfserr_perm;
827 inode = file->f_dentry->d_inode;
828#ifdef MSNFS
829 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
830 (!lock_may_read(inode, offset, *count)))
831 goto out;
832#endif
833
834 /* Get readahead parameters */
835 ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
836
837 if (ra && ra->p_set)
838 file->f_ra = ra->p_ra;
839
840 if (file->f_op->sendfile) {
841 svc_pushback_unused_pages(rqstp);
842 err = file->f_op->sendfile(file, &offset, *count,
843 nfsd_read_actor, rqstp);
844 } else {
845 oldfs = get_fs();
846 set_fs(KERNEL_DS);
847 err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
848 set_fs(oldfs);
849 }
850
851 /* Write back readahead params */
852 if (ra) {
853 spin_lock(&ra_lock);
854 ra->p_ra = file->f_ra;
855 ra->p_set = 1;
856 ra->p_count--;
857 spin_unlock(&ra_lock);
858 }
859
860 if (err >= 0) {
861 nfsdstats.io_read += err;
862 *count = err;
863 err = 0;
864 dnotify_parent(file->f_dentry, DN_ACCESS);
865 } else
866 err = nfserrno(err);
867out:
868 return err;
869}
870
871static inline int
872nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
873 loff_t offset, struct kvec *vec, int vlen,
874 unsigned long cnt, int *stablep)
875{
876 struct svc_export *exp;
877 struct dentry *dentry;
878 struct inode *inode;
879 mm_segment_t oldfs;
880 int err = 0;
881 int stable = *stablep;
882
883 err = nfserr_perm;
884
885#ifdef MSNFS
886 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
887 (!lock_may_write(file->f_dentry->d_inode, offset, cnt)))
888 goto out;
889#endif
890
891 dentry = file->f_dentry;
892 inode = dentry->d_inode;
893 exp = fhp->fh_export;
894
895 /*
896 * Request sync writes if
897 * - the sync export option has been set, or
898 * - the client requested O_SYNC behavior (NFSv3 feature).
899 * - The file system doesn't support fsync().
900 * When gathered writes have been configured for this volume,
901 * flushing the data to disk is handled separately below.
902 */
903
904 if (file->f_op->fsync == 0) {/* COMMIT3 cannot work */
905 stable = 2;
906 *stablep = 2; /* FILE_SYNC */
907 }
908
909 if (!EX_ISSYNC(exp))
910 stable = 0;
911 if (stable && !EX_WGATHER(exp))
912 file->f_flags |= O_SYNC;
913
914 /* Write the data. */
915 oldfs = get_fs(); set_fs(KERNEL_DS);
916 err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset);
917 set_fs(oldfs);
918 if (err >= 0) {
919 nfsdstats.io_write += cnt;
920 dnotify_parent(file->f_dentry, DN_MODIFY);
921 }
922
923 /* clear setuid/setgid flag after write */
924 if (err >= 0 && (inode->i_mode & (S_ISUID | S_ISGID))) {
925 struct iattr ia;
926 ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID;
927
928 down(&inode->i_sem);
929 notify_change(dentry, &ia);
930 up(&inode->i_sem);
931 }
932
933 if (err >= 0 && stable) {
934 static ino_t last_ino;
935 static dev_t last_dev;
936
937 /*
938 * Gathered writes: If another process is currently
939 * writing to the file, there's a high chance
940 * this is another nfsd (triggered by a bulk write
941 * from a client's biod). Rather than syncing the
942 * file with each write request, we sleep for 10 msec.
943 *
944 * I don't know if this roughly approximates
945 * C. Juszak's idea of gathered writes, but it's a
946 * nice and simple solution (IMHO), and it seems to
947 * work:-)
948 */
949 if (EX_WGATHER(exp)) {
950 if (atomic_read(&inode->i_writecount) > 1
951 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
952 dprintk("nfsd: write defer %d\n", current->pid);
953 msleep(10);
954 dprintk("nfsd: write resume %d\n", current->pid);
955 }
956
957 if (inode->i_state & I_DIRTY) {
958 dprintk("nfsd: write sync %d\n", current->pid);
959 nfsd_sync(file);
960 }
961#if 0
962 wake_up(&inode->i_wait);
963#endif
964 }
965 last_ino = inode->i_ino;
966 last_dev = inode->i_sb->s_dev;
967 }
968
969 dprintk("nfsd: write complete err=%d\n", err);
970 if (err >= 0)
971 err = 0;
972 else
973 err = nfserrno(err);
974out:
975 return err;
976}
977
978/*
979 * Read data from a file. count must contain the requested read count
980 * on entry. On return, *count contains the number of bytes actually read.
981 * N.B. After this call fhp needs an fh_put
982 */
983int
984nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
985 loff_t offset, struct kvec *vec, int vlen,
986 unsigned long *count)
987{
988 int err;
989
990 if (file) {
991 err = nfsd_permission(fhp->fh_export, fhp->fh_dentry,
992 MAY_READ|MAY_OWNER_OVERRIDE);
993 if (err)
994 goto out;
995 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
996 } else {
997 err = nfsd_open(rqstp, fhp, S_IFREG, MAY_READ, &file);
998 if (err)
999 goto out;
1000 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1001 nfsd_close(file);
1002 }
1003out:
1004 return err;
1005}
1006
1007/*
1008 * Write data to a file.
1009 * The stable flag requests synchronous writes.
1010 * N.B. After this call fhp needs an fh_put
1011 */
1012int
1013nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1014 loff_t offset, struct kvec *vec, int vlen, unsigned long cnt,
1015 int *stablep)
1016{
1017 int err = 0;
1018
1019 if (file) {
1020 err = nfsd_permission(fhp->fh_export, fhp->fh_dentry,
1021 MAY_WRITE|MAY_OWNER_OVERRIDE);
1022 if (err)
1023 goto out;
1024 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt,
1025 stablep);
1026 } else {
1027 err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file);
1028 if (err)
1029 goto out;
1030
1031 if (cnt)
1032 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen,
1033 cnt, stablep);
1034 nfsd_close(file);
1035 }
1036out:
1037 return err;
1038}
1039
1040#ifdef CONFIG_NFSD_V3
1041/*
1042 * Commit all pending writes to stable storage.
1043 * Strictly speaking, we could sync just the indicated file region here,
1044 * but there's currently no way we can ask the VFS to do so.
1045 *
1046 * Unfortunately we cannot lock the file to make sure we return full WCC
1047 * data to the client, as locking happens lower down in the filesystem.
1048 */
1049int
1050nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
1051 loff_t offset, unsigned long count)
1052{
1053 struct file *file;
1054 int err;
1055
1056 if ((u64)count > ~(u64)offset)
1057 return nfserr_inval;
1058
1059 if ((err = nfsd_open(rqstp, fhp, S_IFREG, MAY_WRITE, &file)) != 0)
1060 return err;
1061 if (EX_ISSYNC(fhp->fh_export)) {
1062 if (file->f_op && file->f_op->fsync) {
1063 nfsd_sync(file);
1064 } else {
1065 err = nfserr_notsupp;
1066 }
1067 }
1068
1069 nfsd_close(file);
1070 return err;
1071}
1072#endif /* CONFIG_NFSD_V3 */
1073
1074/*
1075 * Create a file (regular, directory, device, fifo); UNIX sockets
1076 * not yet implemented.
1077 * If the response fh has been verified, the parent directory should
1078 * already be locked. Note that the parent directory is left locked.
1079 *
1080 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1081 */
1082int
1083nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1084 char *fname, int flen, struct iattr *iap,
1085 int type, dev_t rdev, struct svc_fh *resfhp)
1086{
1087 struct dentry *dentry, *dchild = NULL;
1088 struct inode *dirp;
1089 int err;
1090
1091 err = nfserr_perm;
1092 if (!flen)
1093 goto out;
1094 err = nfserr_exist;
1095 if (isdotent(fname, flen))
1096 goto out;
1097
1098 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
1099 if (err)
1100 goto out;
1101
1102 dentry = fhp->fh_dentry;
1103 dirp = dentry->d_inode;
1104
1105 err = nfserr_notdir;
1106 if(!dirp->i_op || !dirp->i_op->lookup)
1107 goto out;
1108 /*
1109 * Check whether the response file handle has been verified yet.
1110 * If it has, the parent directory should already be locked.
1111 */
1112 if (!resfhp->fh_dentry) {
1113 /* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */
1114 fh_lock(fhp);
1115 dchild = lookup_one_len(fname, dentry, flen);
1116 err = PTR_ERR(dchild);
1117 if (IS_ERR(dchild))
1118 goto out_nfserr;
1119 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1120 if (err)
1121 goto out;
1122 } else {
1123 /* called from nfsd_proc_create */
1124 dchild = dget(resfhp->fh_dentry);
1125 if (!fhp->fh_locked) {
1126 /* not actually possible */
1127 printk(KERN_ERR
1128 "nfsd_create: parent %s/%s not locked!\n",
1129 dentry->d_parent->d_name.name,
1130 dentry->d_name.name);
1131 err = -EIO;
1132 goto out;
1133 }
1134 }
1135 /*
1136 * Make sure the child dentry is still negative ...
1137 */
1138 err = nfserr_exist;
1139 if (dchild->d_inode) {
1140 dprintk("nfsd_create: dentry %s/%s not negative!\n",
1141 dentry->d_name.name, dchild->d_name.name);
1142 goto out;
1143 }
1144
1145 if (!(iap->ia_valid & ATTR_MODE))
1146 iap->ia_mode = 0;
1147 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
1148
1149 /*
1150 * Get the dir op function pointer.
1151 */
1152 err = nfserr_perm;
1153 switch (type) {
1154 case S_IFREG:
1155 err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1156 break;
1157 case S_IFDIR:
1158 err = vfs_mkdir(dirp, dchild, iap->ia_mode);
1159 break;
1160 case S_IFCHR:
1161 case S_IFBLK:
1162 case S_IFIFO:
1163 case S_IFSOCK:
1164 err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
1165 break;
1166 default:
1167 printk("nfsd: bad file type %o in nfsd_create\n", type);
1168 err = -EINVAL;
1169 }
1170 if (err < 0)
1171 goto out_nfserr;
1172
1173 if (EX_ISSYNC(fhp->fh_export)) {
1174 nfsd_sync_dir(dentry);
1175 write_inode_now(dchild->d_inode, 1);
1176 }
1177
1178
1179 /* Set file attributes. Mode has already been set and
1180 * setting uid/gid works only for root. Irix appears to
1181 * send along the gid when it tries to implement setgid
1182 * directories via NFS.
1183 */
1184 err = 0;
1185 if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID|ATTR_MODE)) != 0)
1186 err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
1187 /*
1188 * Update the file handle to get the new inode info.
1189 */
1190 if (!err)
1191 err = fh_update(resfhp);
1192out:
1193 if (dchild && !IS_ERR(dchild))
1194 dput(dchild);
1195 return err;
1196
1197out_nfserr:
1198 err = nfserrno(err);
1199 goto out;
1200}
1201
1202#ifdef CONFIG_NFSD_V3
1203/*
1204 * NFSv3 version of nfsd_create
1205 */
1206int
1207nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
1208 char *fname, int flen, struct iattr *iap,
1209 struct svc_fh *resfhp, int createmode, u32 *verifier,
1210 int *truncp)
1211{
1212 struct dentry *dentry, *dchild = NULL;
1213 struct inode *dirp;
1214 int err;
1215 __u32 v_mtime=0, v_atime=0;
1216 int v_mode=0;
1217
1218 err = nfserr_perm;
1219 if (!flen)
1220 goto out;
1221 err = nfserr_exist;
1222 if (isdotent(fname, flen))
1223 goto out;
1224 if (!(iap->ia_valid & ATTR_MODE))
1225 iap->ia_mode = 0;
1226 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
1227 if (err)
1228 goto out;
1229
1230 dentry = fhp->fh_dentry;
1231 dirp = dentry->d_inode;
1232
1233 /* Get all the sanity checks out of the way before
1234 * we lock the parent. */
1235 err = nfserr_notdir;
1236 if(!dirp->i_op || !dirp->i_op->lookup)
1237 goto out;
1238 fh_lock(fhp);
1239
1240 /*
1241 * Compose the response file handle.
1242 */
1243 dchild = lookup_one_len(fname, dentry, flen);
1244 err = PTR_ERR(dchild);
1245 if (IS_ERR(dchild))
1246 goto out_nfserr;
1247
1248 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1249 if (err)
1250 goto out;
1251
1252 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1253 /* while the verifier would fit in mtime+atime,
1254 * solaris7 gets confused (bugid 4218508) if these have
1255 * the high bit set, so we use the mode as well
1256 */
1257 v_mtime = verifier[0]&0x7fffffff;
1258 v_atime = verifier[1]&0x7fffffff;
1259 v_mode = S_IFREG
1260 | ((verifier[0]&0x80000000) >> (32-7)) /* u+x */
1261 | ((verifier[1]&0x80000000) >> (32-9)) /* u+r */
1262 ;
1263 }
1264
1265 if (dchild->d_inode) {
1266 err = 0;
1267
1268 switch (createmode) {
1269 case NFS3_CREATE_UNCHECKED:
1270 if (! S_ISREG(dchild->d_inode->i_mode))
1271 err = nfserr_exist;
1272 else if (truncp) {
1273 /* in nfsv4, we need to treat this case a little
1274 * differently. we don't want to truncate the
1275 * file now; this would be wrong if the OPEN
1276 * fails for some other reason. furthermore,
1277 * if the size is nonzero, we should ignore it
1278 * according to spec!
1279 */
1280 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size;
1281 }
1282 else {
1283 iap->ia_valid &= ATTR_SIZE;
1284 goto set_attr;
1285 }
1286 break;
1287 case NFS3_CREATE_EXCLUSIVE:
1288 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime
1289 && dchild->d_inode->i_atime.tv_sec == v_atime
1290 && dchild->d_inode->i_mode == v_mode
1291 && dchild->d_inode->i_size == 0 )
1292 break;
1293 /* fallthru */
1294 case NFS3_CREATE_GUARDED:
1295 err = nfserr_exist;
1296 }
1297 goto out;
1298 }
1299
1300 err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1301 if (err < 0)
1302 goto out_nfserr;
1303
1304 if (EX_ISSYNC(fhp->fh_export)) {
1305 nfsd_sync_dir(dentry);
1306 /* setattr will sync the child (or not) */
1307 }
1308
1309 /*
1310 * Update the filehandle to get the new inode info.
1311 */
1312 err = fh_update(resfhp);
1313 if (err)
1314 goto out;
1315
1316 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1317 /* Cram the verifier into atime/mtime/mode */
1318 iap->ia_valid = ATTR_MTIME|ATTR_ATIME
1319 | ATTR_MTIME_SET|ATTR_ATIME_SET
1320 | ATTR_MODE;
1321 /* XXX someone who knows this better please fix it for nsec */
1322 iap->ia_mtime.tv_sec = v_mtime;
1323 iap->ia_atime.tv_sec = v_atime;
1324 iap->ia_mtime.tv_nsec = 0;
1325 iap->ia_atime.tv_nsec = 0;
1326 iap->ia_mode = v_mode;
1327 }
1328
1329 /* Set file attributes.
1330 * Mode has already been set but we might need to reset it
1331 * for CREATE_EXCLUSIVE
1332 * Irix appears to send along the gid when it tries to
1333 * implement setgid directories via NFS. Clear out all that cruft.
1334 */
1335 set_attr:
1336 if ((iap->ia_valid &= ~(ATTR_UID|ATTR_GID)) != 0)
1337 err = nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
1338
1339 out:
1340 fh_unlock(fhp);
1341 if (dchild && !IS_ERR(dchild))
1342 dput(dchild);
1343 return err;
1344
1345 out_nfserr:
1346 err = nfserrno(err);
1347 goto out;
1348}
1349#endif /* CONFIG_NFSD_V3 */
1350
1351/*
1352 * Read a symlink. On entry, *lenp must contain the maximum path length that
1353 * fits into the buffer. On return, it contains the true length.
1354 * N.B. After this call fhp needs an fh_put
1355 */
1356int
1357nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
1358{
1359 struct dentry *dentry;
1360 struct inode *inode;
1361 mm_segment_t oldfs;
1362 int err;
1363
1364 err = fh_verify(rqstp, fhp, S_IFLNK, MAY_NOP);
1365 if (err)
1366 goto out;
1367
1368 dentry = fhp->fh_dentry;
1369 inode = dentry->d_inode;
1370
1371 err = nfserr_inval;
1372 if (!inode->i_op || !inode->i_op->readlink)
1373 goto out;
1374
1375 touch_atime(fhp->fh_export->ex_mnt, dentry);
1376 /* N.B. Why does this call need a get_fs()??
1377 * Remove the set_fs and watch the fireworks:-) --okir
1378 */
1379
1380 oldfs = get_fs(); set_fs(KERNEL_DS);
1381 err = inode->i_op->readlink(dentry, buf, *lenp);
1382 set_fs(oldfs);
1383
1384 if (err < 0)
1385 goto out_nfserr;
1386 *lenp = err;
1387 err = 0;
1388out:
1389 return err;
1390
1391out_nfserr:
1392 err = nfserrno(err);
1393 goto out;
1394}
1395
1396/*
1397 * Create a symlink and look up its inode
1398 * N.B. After this call _both_ fhp and resfhp need an fh_put
1399 */
1400int
1401nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
1402 char *fname, int flen,
1403 char *path, int plen,
1404 struct svc_fh *resfhp,
1405 struct iattr *iap)
1406{
1407 struct dentry *dentry, *dnew;
1408 int err, cerr;
1409 umode_t mode;
1410
1411 err = nfserr_noent;
1412 if (!flen || !plen)
1413 goto out;
1414 err = nfserr_exist;
1415 if (isdotent(fname, flen))
1416 goto out;
1417
1418 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_CREATE);
1419 if (err)
1420 goto out;
1421 fh_lock(fhp);
1422 dentry = fhp->fh_dentry;
1423 dnew = lookup_one_len(fname, dentry, flen);
1424 err = PTR_ERR(dnew);
1425 if (IS_ERR(dnew))
1426 goto out_nfserr;
1427
1428 mode = S_IALLUGO;
1429 /* Only the MODE ATTRibute is even vaguely meaningful */
1430 if (iap && (iap->ia_valid & ATTR_MODE))
1431 mode = iap->ia_mode & S_IALLUGO;
1432
1433 if (unlikely(path[plen] != 0)) {
1434 char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
1435 if (path_alloced == NULL)
1436 err = -ENOMEM;
1437 else {
1438 strncpy(path_alloced, path, plen);
1439 path_alloced[plen] = 0;
1440 err = vfs_symlink(dentry->d_inode, dnew, path_alloced, mode);
1441 kfree(path_alloced);
1442 }
1443 } else
1444 err = vfs_symlink(dentry->d_inode, dnew, path, mode);
1445
1446 if (!err) {
1447 if (EX_ISSYNC(fhp->fh_export))
1448 nfsd_sync_dir(dentry);
1449 } else
1450 err = nfserrno(err);
1451 fh_unlock(fhp);
1452
1453 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
1454 dput(dnew);
1455 if (err==0) err = cerr;
1456out:
1457 return err;
1458
1459out_nfserr:
1460 err = nfserrno(err);
1461 goto out;
1462}
1463
1464/*
1465 * Create a hardlink
1466 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1467 */
1468int
1469nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
1470 char *name, int len, struct svc_fh *tfhp)
1471{
1472 struct dentry *ddir, *dnew, *dold;
1473 struct inode *dirp, *dest;
1474 int err;
1475
1476 err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_CREATE);
1477 if (err)
1478 goto out;
1479 err = fh_verify(rqstp, tfhp, -S_IFDIR, MAY_NOP);
1480 if (err)
1481 goto out;
1482
1483 err = nfserr_perm;
1484 if (!len)
1485 goto out;
1486 err = nfserr_exist;
1487 if (isdotent(name, len))
1488 goto out;
1489
1490 fh_lock(ffhp);
1491 ddir = ffhp->fh_dentry;
1492 dirp = ddir->d_inode;
1493
1494 dnew = lookup_one_len(name, ddir, len);
1495 err = PTR_ERR(dnew);
1496 if (IS_ERR(dnew))
1497 goto out_nfserr;
1498
1499 dold = tfhp->fh_dentry;
1500 dest = dold->d_inode;
1501
1502 err = vfs_link(dold, dirp, dnew);
1503 if (!err) {
1504 if (EX_ISSYNC(ffhp->fh_export)) {
1505 nfsd_sync_dir(ddir);
1506 write_inode_now(dest, 1);
1507 }
1508 } else {
1509 if (err == -EXDEV && rqstp->rq_vers == 2)
1510 err = nfserr_acces;
1511 else
1512 err = nfserrno(err);
1513 }
1514
1515 fh_unlock(ffhp);
1516 dput(dnew);
1517out:
1518 return err;
1519
1520out_nfserr:
1521 err = nfserrno(err);
1522 goto out;
1523}
1524
1525/*
1526 * Rename a file
1527 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1528 */
1529int
1530nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
1531 struct svc_fh *tfhp, char *tname, int tlen)
1532{
1533 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
1534 struct inode *fdir, *tdir;
1535 int err;
1536
1537 err = fh_verify(rqstp, ffhp, S_IFDIR, MAY_REMOVE);
1538 if (err)
1539 goto out;
1540 err = fh_verify(rqstp, tfhp, S_IFDIR, MAY_CREATE);
1541 if (err)
1542 goto out;
1543
1544 fdentry = ffhp->fh_dentry;
1545 fdir = fdentry->d_inode;
1546
1547 tdentry = tfhp->fh_dentry;
1548 tdir = tdentry->d_inode;
1549
1550 err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
1551 if (fdir->i_sb != tdir->i_sb)
1552 goto out;
1553
1554 err = nfserr_perm;
1555 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
1556 goto out;
1557
1558 /* cannot use fh_lock as we need deadlock protective ordering
1559 * so do it by hand */
1560 trap = lock_rename(tdentry, fdentry);
1561 ffhp->fh_locked = tfhp->fh_locked = 1;
1562 fill_pre_wcc(ffhp);
1563 fill_pre_wcc(tfhp);
1564
1565 odentry = lookup_one_len(fname, fdentry, flen);
1566 err = PTR_ERR(odentry);
1567 if (IS_ERR(odentry))
1568 goto out_nfserr;
1569
1570 err = -ENOENT;
1571 if (!odentry->d_inode)
1572 goto out_dput_old;
1573 err = -EINVAL;
1574 if (odentry == trap)
1575 goto out_dput_old;
1576
1577 ndentry = lookup_one_len(tname, tdentry, tlen);
1578 err = PTR_ERR(ndentry);
1579 if (IS_ERR(ndentry))
1580 goto out_dput_old;
1581 err = -ENOTEMPTY;
1582 if (ndentry == trap)
1583 goto out_dput_new;
1584
1585#ifdef MSNFS
1586 if ((ffhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1587 ((atomic_read(&odentry->d_count) > 1)
1588 || (atomic_read(&ndentry->d_count) > 1))) {
1589 err = nfserr_perm;
1590 } else
1591#endif
1592 err = vfs_rename(fdir, odentry, tdir, ndentry);
1593 if (!err && EX_ISSYNC(tfhp->fh_export)) {
1594 nfsd_sync_dir(tdentry);
1595 nfsd_sync_dir(fdentry);
1596 }
1597
1598 out_dput_new:
1599 dput(ndentry);
1600 out_dput_old:
1601 dput(odentry);
1602 out_nfserr:
1603 if (err)
1604 err = nfserrno(err);
1605
1606 /* we cannot reply on fh_unlock on the two filehandles,
1607 * as that would do the wrong thing if the two directories
1608 * were the same, so again we do it by hand
1609 */
1610 fill_post_wcc(ffhp);
1611 fill_post_wcc(tfhp);
1612 unlock_rename(tdentry, fdentry);
1613 ffhp->fh_locked = tfhp->fh_locked = 0;
1614
1615out:
1616 return err;
1617}
1618
1619/*
1620 * Unlink a file or directory
1621 * N.B. After this call fhp needs an fh_put
1622 */
1623int
1624nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
1625 char *fname, int flen)
1626{
1627 struct dentry *dentry, *rdentry;
1628 struct inode *dirp;
1629 int err;
1630
1631 err = nfserr_acces;
1632 if (!flen || isdotent(fname, flen))
1633 goto out;
1634 err = fh_verify(rqstp, fhp, S_IFDIR, MAY_REMOVE);
1635 if (err)
1636 goto out;
1637
1638 fh_lock(fhp);
1639 dentry = fhp->fh_dentry;
1640 dirp = dentry->d_inode;
1641
1642 rdentry = lookup_one_len(fname, dentry, flen);
1643 err = PTR_ERR(rdentry);
1644 if (IS_ERR(rdentry))
1645 goto out_nfserr;
1646
1647 if (!rdentry->d_inode) {
1648 dput(rdentry);
1649 err = nfserr_noent;
1650 goto out;
1651 }
1652
1653 if (!type)
1654 type = rdentry->d_inode->i_mode & S_IFMT;
1655
1656 if (type != S_IFDIR) { /* It's UNLINK */
1657#ifdef MSNFS
1658 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1659 (atomic_read(&rdentry->d_count) > 1)) {
1660 err = nfserr_perm;
1661 } else
1662#endif
1663 err = vfs_unlink(dirp, rdentry);
1664 } else { /* It's RMDIR */
1665 err = vfs_rmdir(dirp, rdentry);
1666 }
1667
1668 dput(rdentry);
1669
1670 if (err)
1671 goto out_nfserr;
1672 if (EX_ISSYNC(fhp->fh_export))
1673 nfsd_sync_dir(dentry);
1674
1675out:
1676 return err;
1677
1678out_nfserr:
1679 err = nfserrno(err);
1680 goto out;
1681}
1682
1683/*
1684 * Read entries from a directory.
1685 * The NFSv3/4 verifier we ignore for now.
1686 */
1687int
1688nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
1689 struct readdir_cd *cdp, encode_dent_fn func)
1690{
1691 int err;
1692 struct file *file;
1693 loff_t offset = *offsetp;
1694
1695 err = nfsd_open(rqstp, fhp, S_IFDIR, MAY_READ, &file);
1696 if (err)
1697 goto out;
1698
1699 offset = vfs_llseek(file, offset, 0);
1700 if (offset < 0) {
1701 err = nfserrno((int)offset);
1702 goto out_close;
1703 }
1704
1705 /*
1706 * Read the directory entries. This silly loop is necessary because
1707 * readdir() is not guaranteed to fill up the entire buffer, but
1708 * may choose to do less.
1709 */
1710
1711 do {
1712 cdp->err = nfserr_eof; /* will be cleared on successful read */
1713 err = vfs_readdir(file, (filldir_t) func, cdp);
1714 } while (err >=0 && cdp->err == nfs_ok);
1715 if (err)
1716 err = nfserrno(err);
1717 else
1718 err = cdp->err;
1719 *offsetp = vfs_llseek(file, 0, 1);
1720
1721 if (err == nfserr_eof || err == nfserr_toosmall)
1722 err = nfs_ok; /* can still be found in ->err */
1723out_close:
1724 nfsd_close(file);
1725out:
1726 return err;
1727}
1728
1729/*
1730 * Get file system stats
1731 * N.B. After this call fhp needs an fh_put
1732 */
1733int
1734nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat)
1735{
1736 int err = fh_verify(rqstp, fhp, 0, MAY_NOP);
1737 if (!err && vfs_statfs(fhp->fh_dentry->d_inode->i_sb,stat))
1738 err = nfserr_io;
1739 return err;
1740}
1741
1742/*
1743 * Check for a user's access permissions to this inode.
1744 */
1745int
1746nfsd_permission(struct svc_export *exp, struct dentry *dentry, int acc)
1747{
1748 struct inode *inode = dentry->d_inode;
1749 int err;
1750
1751 if (acc == MAY_NOP)
1752 return 0;
1753#if 0
1754 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
1755 acc,
1756 (acc & MAY_READ)? " read" : "",
1757 (acc & MAY_WRITE)? " write" : "",
1758 (acc & MAY_EXEC)? " exec" : "",
1759 (acc & MAY_SATTR)? " sattr" : "",
1760 (acc & MAY_TRUNC)? " trunc" : "",
1761 (acc & MAY_LOCK)? " lock" : "",
1762 (acc & MAY_OWNER_OVERRIDE)? " owneroverride" : "",
1763 inode->i_mode,
1764 IS_IMMUTABLE(inode)? " immut" : "",
1765 IS_APPEND(inode)? " append" : "",
1766 IS_RDONLY(inode)? " ro" : "");
1767 dprintk(" owner %d/%d user %d/%d\n",
1768 inode->i_uid, inode->i_gid, current->fsuid, current->fsgid);
1769#endif
1770
1771 /* Normally we reject any write/sattr etc access on a read-only file
1772 * system. But if it is IRIX doing check on write-access for a
1773 * device special file, we ignore rofs.
1774 */
1775 if (!(acc & MAY_LOCAL_ACCESS))
1776 if (acc & (MAY_WRITE | MAY_SATTR | MAY_TRUNC)) {
1777 if (EX_RDONLY(exp) || IS_RDONLY(inode))
1778 return nfserr_rofs;
1779 if (/* (acc & MAY_WRITE) && */ IS_IMMUTABLE(inode))
1780 return nfserr_perm;
1781 }
1782 if ((acc & MAY_TRUNC) && IS_APPEND(inode))
1783 return nfserr_perm;
1784
1785 if (acc & MAY_LOCK) {
1786 /* If we cannot rely on authentication in NLM requests,
1787 * just allow locks, otherwise require read permission, or
1788 * ownership
1789 */
1790 if (exp->ex_flags & NFSEXP_NOAUTHNLM)
1791 return 0;
1792 else
1793 acc = MAY_READ | MAY_OWNER_OVERRIDE;
1794 }
1795 /*
1796 * The file owner always gets access permission for accesses that
1797 * would normally be checked at open time. This is to make
1798 * file access work even when the client has done a fchmod(fd, 0).
1799 *
1800 * However, `cp foo bar' should fail nevertheless when bar is
1801 * readonly. A sensible way to do this might be to reject all
1802 * attempts to truncate a read-only file, because a creat() call
1803 * always implies file truncation.
1804 * ... but this isn't really fair. A process may reasonably call
1805 * ftruncate on an open file descriptor on a file with perm 000.
1806 * We must trust the client to do permission checking - using "ACCESS"
1807 * with NFSv3.
1808 */
1809 if ((acc & MAY_OWNER_OVERRIDE) &&
1810 inode->i_uid == current->fsuid)
1811 return 0;
1812
1813 err = permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), NULL);
1814
1815 /* Allow read access to binaries even when mode 111 */
1816 if (err == -EACCES && S_ISREG(inode->i_mode) &&
1817 acc == (MAY_READ | MAY_OWNER_OVERRIDE))
1818 err = permission(inode, MAY_EXEC, NULL);
1819
1820 return err? nfserrno(err) : 0;
1821}
1822
1823void
1824nfsd_racache_shutdown(void)
1825{
1826 if (!raparm_cache)
1827 return;
1828 dprintk("nfsd: freeing readahead buffers.\n");
1829 kfree(raparml);
1830 raparm_cache = raparml = NULL;
1831}
1832/*
1833 * Initialize readahead param cache
1834 */
1835int
1836nfsd_racache_init(int cache_size)
1837{
1838 int i;
1839
1840 if (raparm_cache)
1841 return 0;
1842 raparml = kmalloc(sizeof(struct raparms) * cache_size, GFP_KERNEL);
1843
1844 if (raparml != NULL) {
1845 dprintk("nfsd: allocating %d readahead buffers.\n",
1846 cache_size);
1847 memset(raparml, 0, sizeof(struct raparms) * cache_size);
1848 for (i = 0; i < cache_size - 1; i++) {
1849 raparml[i].p_next = raparml + i + 1;
1850 }
1851 raparm_cache = raparml;
1852 } else {
1853 printk(KERN_WARNING
1854 "nfsd: Could not allocate memory read-ahead cache.\n");
1855 return -ENOMEM;
1856 }
1857 nfsdstats.ra_size = cache_size;
1858 return 0;
1859}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-21 10:39:10 -0500