perf, x86, Do not user perf_disable from NMI context
[linux-2.6.git] / fs / nfsd / vfs.c
bloba11b0e8678eeff6585687afe1d0701663e11144a
1 #define MSNFS /* HACK HACK */
2 /*
3 * File operations used by nfsd. Some of these have been ripped from
4 * other parts of the kernel because they weren't exported, others
5 * are partial duplicates with added or changed functionality.
7 * Note that several functions dget() the dentry upon which they want
8 * to act, most notably those that create directory entries. Response
9 * dentry's are dput()'d if necessary in the release callback.
10 * So if you notice code paths that apparently fail to dput() the
11 * dentry, don't worry--they have been taken care of.
13 * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de>
14 * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp>
17 #include <linux/fs.h>
18 #include <linux/file.h>
19 #include <linux/splice.h>
20 #include <linux/fcntl.h>
21 #include <linux/namei.h>
22 #include <linux/delay.h>
23 #include <linux/fsnotify.h>
24 #include <linux/posix_acl_xattr.h>
25 #include <linux/xattr.h>
26 #include <linux/jhash.h>
27 #include <linux/ima.h>
28 #include <asm/uaccess.h>
29 #include <linux/exportfs.h>
30 #include <linux/writeback.h>
32 #ifdef CONFIG_NFSD_V3
33 #include "xdr3.h"
34 #endif /* CONFIG_NFSD_V3 */
36 #ifdef CONFIG_NFSD_V4
37 #include <linux/nfs4_acl.h>
38 #include <linux/nfsd_idmap.h>
39 #endif /* CONFIG_NFSD_V4 */
41 #include "nfsd.h"
42 #include "vfs.h"
44 #define NFSDDBG_FACILITY NFSDDBG_FILEOP
48 * This is a cache of readahead params that help us choose the proper
49 * readahead strategy. Initially, we set all readahead parameters to 0
50 * and let the VFS handle things.
51 * If you increase the number of cached files very much, you'll need to
52 * add a hash table here.
54 struct raparms {
55 struct raparms *p_next;
56 unsigned int p_count;
57 ino_t p_ino;
58 dev_t p_dev;
59 int p_set;
60 struct file_ra_state p_ra;
61 unsigned int p_hindex;
64 struct raparm_hbucket {
65 struct raparms *pb_head;
66 spinlock_t pb_lock;
67 } ____cacheline_aligned_in_smp;
69 #define RAPARM_HASH_BITS 4
70 #define RAPARM_HASH_SIZE (1<<RAPARM_HASH_BITS)
71 #define RAPARM_HASH_MASK (RAPARM_HASH_SIZE-1)
72 static struct raparm_hbucket raparm_hash[RAPARM_HASH_SIZE];
74 /*
75 * Called from nfsd_lookup and encode_dirent. Check if we have crossed
76 * a mount point.
77 * Returns -EAGAIN or -ETIMEDOUT leaving *dpp and *expp unchanged,
78 * or nfs_ok having possibly changed *dpp and *expp
80 int
81 nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
82 struct svc_export **expp)
84 struct svc_export *exp = *expp, *exp2 = NULL;
85 struct dentry *dentry = *dpp;
86 struct path path = {.mnt = mntget(exp->ex_path.mnt),
87 .dentry = dget(dentry)};
88 int err = 0;
90 while (d_mountpoint(path.dentry) && follow_down(&path))
93 exp2 = rqst_exp_get_by_name(rqstp, &path);
94 if (IS_ERR(exp2)) {
95 err = PTR_ERR(exp2);
97 * We normally allow NFS clients to continue
98 * "underneath" a mountpoint that is not exported.
99 * The exception is V4ROOT, where no traversal is ever
100 * allowed without an explicit export of the new
101 * directory.
103 if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
104 err = 0;
105 path_put(&path);
106 goto out;
108 if (nfsd_v4client(rqstp) ||
109 (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
110 /* successfully crossed mount point */
112 * This is subtle: path.dentry is *not* on path.mnt
113 * at this point. The only reason we are safe is that
114 * original mnt is pinned down by exp, so we should
115 * put path *before* putting exp
117 *dpp = path.dentry;
118 path.dentry = dentry;
119 *expp = exp2;
120 exp2 = exp;
122 path_put(&path);
123 exp_put(exp2);
124 out:
125 return err;
128 static void follow_to_parent(struct path *path)
130 struct dentry *dp;
132 while (path->dentry == path->mnt->mnt_root && follow_up(path))
134 dp = dget_parent(path->dentry);
135 dput(path->dentry);
136 path->dentry = dp;
139 static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
141 struct svc_export *exp2;
142 struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
143 .dentry = dget(dparent)};
145 follow_to_parent(&path);
147 exp2 = rqst_exp_parent(rqstp, &path);
148 if (PTR_ERR(exp2) == -ENOENT) {
149 *dentryp = dget(dparent);
150 } else if (IS_ERR(exp2)) {
151 path_put(&path);
152 return PTR_ERR(exp2);
153 } else {
154 *dentryp = dget(path.dentry);
155 exp_put(*exp);
156 *exp = exp2;
158 path_put(&path);
159 return 0;
163 * For nfsd purposes, we treat V4ROOT exports as though there was an
164 * export at *every* directory.
166 int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
168 if (d_mountpoint(dentry))
169 return 1;
170 if (!(exp->ex_flags & NFSEXP_V4ROOT))
171 return 0;
172 return dentry->d_inode != NULL;
175 __be32
176 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
177 const char *name, unsigned int len,
178 struct svc_export **exp_ret, struct dentry **dentry_ret)
180 struct svc_export *exp;
181 struct dentry *dparent;
182 struct dentry *dentry;
183 __be32 err;
184 int host_err;
186 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
188 /* Obtain dentry and export. */
189 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
190 if (err)
191 return err;
193 dparent = fhp->fh_dentry;
194 exp = fhp->fh_export;
195 exp_get(exp);
197 /* Lookup the name, but don't follow links */
198 if (isdotent(name, len)) {
199 if (len==1)
200 dentry = dget(dparent);
201 else if (dparent != exp->ex_path.dentry)
202 dentry = dget_parent(dparent);
203 else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
204 dentry = dget(dparent); /* .. == . just like at / */
205 else {
206 /* checking mountpoint crossing is very different when stepping up */
207 host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
208 if (host_err)
209 goto out_nfserr;
211 } else {
212 fh_lock(fhp);
213 dentry = lookup_one_len(name, dparent, len);
214 host_err = PTR_ERR(dentry);
215 if (IS_ERR(dentry))
216 goto out_nfserr;
218 * check if we have crossed a mount point ...
220 if (nfsd_mountpoint(dentry, exp)) {
221 if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
222 dput(dentry);
223 goto out_nfserr;
227 *dentry_ret = dentry;
228 *exp_ret = exp;
229 return 0;
231 out_nfserr:
232 exp_put(exp);
233 return nfserrno(host_err);
237 * Look up one component of a pathname.
238 * N.B. After this call _both_ fhp and resfh need an fh_put
240 * If the lookup would cross a mountpoint, and the mounted filesystem
241 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
242 * accepted as it stands and the mounted directory is
243 * returned. Otherwise the covered directory is returned.
244 * NOTE: this mountpoint crossing is not supported properly by all
245 * clients and is explicitly disallowed for NFSv3
246 * NeilBrown <neilb@cse.unsw.edu.au>
248 __be32
249 nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
250 unsigned int len, struct svc_fh *resfh)
252 struct svc_export *exp;
253 struct dentry *dentry;
254 __be32 err;
256 err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
257 if (err)
258 return err;
259 err = check_nfsd_access(exp, rqstp);
260 if (err)
261 goto out;
263 * Note: we compose the file handle now, but as the
264 * dentry may be negative, it may need to be updated.
266 err = fh_compose(resfh, exp, dentry, fhp);
267 if (!err && !dentry->d_inode)
268 err = nfserr_noent;
269 out:
270 dput(dentry);
271 exp_put(exp);
272 return err;
276 * Commit metadata changes to stable storage.
278 static int
279 commit_metadata(struct svc_fh *fhp)
281 struct inode *inode = fhp->fh_dentry->d_inode;
282 const struct export_operations *export_ops = inode->i_sb->s_export_op;
283 int error = 0;
285 if (!EX_ISSYNC(fhp->fh_export))
286 return 0;
288 if (export_ops->commit_metadata) {
289 error = export_ops->commit_metadata(inode);
290 } else {
291 struct writeback_control wbc = {
292 .sync_mode = WB_SYNC_ALL,
293 .nr_to_write = 0, /* metadata only */
296 error = sync_inode(inode, &wbc);
299 return error;
303 * Set various file attributes.
304 * N.B. After this call fhp needs an fh_put
306 __be32
307 nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
308 int check_guard, time_t guardtime)
310 struct dentry *dentry;
311 struct inode *inode;
312 int accmode = NFSD_MAY_SATTR;
313 int ftype = 0;
314 __be32 err;
315 int host_err;
316 int size_change = 0;
318 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
319 accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
320 if (iap->ia_valid & ATTR_SIZE)
321 ftype = S_IFREG;
323 /* Get inode */
324 err = fh_verify(rqstp, fhp, ftype, accmode);
325 if (err)
326 goto out;
328 dentry = fhp->fh_dentry;
329 inode = dentry->d_inode;
331 /* Ignore any mode updates on symlinks */
332 if (S_ISLNK(inode->i_mode))
333 iap->ia_valid &= ~ATTR_MODE;
335 if (!iap->ia_valid)
336 goto out;
339 * NFSv2 does not differentiate between "set-[ac]time-to-now"
340 * which only requires access, and "set-[ac]time-to-X" which
341 * requires ownership.
342 * So if it looks like it might be "set both to the same time which
343 * is close to now", and if inode_change_ok fails, then we
344 * convert to "set to now" instead of "set to explicit time"
346 * We only call inode_change_ok as the last test as technically
347 * it is not an interface that we should be using. It is only
348 * valid if the filesystem does not define it's own i_op->setattr.
350 #define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
351 #define MAX_TOUCH_TIME_ERROR (30*60)
352 if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET &&
353 iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec) {
355 * Looks probable.
357 * Now just make sure time is in the right ballpark.
358 * Solaris, at least, doesn't seem to care what the time
359 * request is. We require it be within 30 minutes of now.
361 time_t delta = iap->ia_atime.tv_sec - get_seconds();
362 if (delta < 0)
363 delta = -delta;
364 if (delta < MAX_TOUCH_TIME_ERROR &&
365 inode_change_ok(inode, iap) != 0) {
367 * Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
368 * This will cause notify_change to set these times
369 * to "now"
371 iap->ia_valid &= ~BOTH_TIME_SET;
376 * The size case is special.
377 * It changes the file as well as the attributes.
379 if (iap->ia_valid & ATTR_SIZE) {
380 if (iap->ia_size < inode->i_size) {
381 err = nfsd_permission(rqstp, fhp->fh_export, dentry,
382 NFSD_MAY_TRUNC|NFSD_MAY_OWNER_OVERRIDE);
383 if (err)
384 goto out;
388 * If we are changing the size of the file, then
389 * we need to break all leases.
391 host_err = break_lease(inode, O_WRONLY | O_NONBLOCK);
392 if (host_err == -EWOULDBLOCK)
393 host_err = -ETIMEDOUT;
394 if (host_err) /* ENOMEM or EWOULDBLOCK */
395 goto out_nfserr;
397 host_err = get_write_access(inode);
398 if (host_err)
399 goto out_nfserr;
401 size_change = 1;
402 host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
403 if (host_err) {
404 put_write_access(inode);
405 goto out_nfserr;
409 /* sanitize the mode change */
410 if (iap->ia_valid & ATTR_MODE) {
411 iap->ia_mode &= S_IALLUGO;
412 iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
415 /* Revoke setuid/setgid on chown */
416 if (!S_ISDIR(inode->i_mode) &&
417 (((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid) ||
418 ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid))) {
419 iap->ia_valid |= ATTR_KILL_PRIV;
420 if (iap->ia_valid & ATTR_MODE) {
421 /* we're setting mode too, just clear the s*id bits */
422 iap->ia_mode &= ~S_ISUID;
423 if (iap->ia_mode & S_IXGRP)
424 iap->ia_mode &= ~S_ISGID;
425 } else {
426 /* set ATTR_KILL_* bits and let VFS handle it */
427 iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
431 /* Change the attributes. */
433 iap->ia_valid |= ATTR_CTIME;
435 err = nfserr_notsync;
436 if (!check_guard || guardtime == inode->i_ctime.tv_sec) {
437 fh_lock(fhp);
438 host_err = notify_change(dentry, iap);
439 err = nfserrno(host_err);
440 fh_unlock(fhp);
442 if (size_change)
443 put_write_access(inode);
444 if (!err)
445 if (EX_ISSYNC(fhp->fh_export))
446 write_inode_now(inode, 1);
447 out:
448 return err;
450 out_nfserr:
451 err = nfserrno(host_err);
452 goto out;
455 #if defined(CONFIG_NFSD_V2_ACL) || \
456 defined(CONFIG_NFSD_V3_ACL) || \
457 defined(CONFIG_NFSD_V4)
458 static ssize_t nfsd_getxattr(struct dentry *dentry, char *key, void **buf)
460 ssize_t buflen;
461 ssize_t ret;
463 buflen = vfs_getxattr(dentry, key, NULL, 0);
464 if (buflen <= 0)
465 return buflen;
467 *buf = kmalloc(buflen, GFP_KERNEL);
468 if (!*buf)
469 return -ENOMEM;
471 ret = vfs_getxattr(dentry, key, *buf, buflen);
472 if (ret < 0)
473 kfree(*buf);
474 return ret;
476 #endif
478 #if defined(CONFIG_NFSD_V4)
479 static int
480 set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key)
482 int len;
483 size_t buflen;
484 char *buf = NULL;
485 int error = 0;
487 buflen = posix_acl_xattr_size(pacl->a_count);
488 buf = kmalloc(buflen, GFP_KERNEL);
489 error = -ENOMEM;
490 if (buf == NULL)
491 goto out;
493 len = posix_acl_to_xattr(pacl, buf, buflen);
494 if (len < 0) {
495 error = len;
496 goto out;
499 error = vfs_setxattr(dentry, key, buf, len, 0);
500 out:
501 kfree(buf);
502 return error;
505 __be32
506 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
507 struct nfs4_acl *acl)
509 __be32 error;
510 int host_error;
511 struct dentry *dentry;
512 struct inode *inode;
513 struct posix_acl *pacl = NULL, *dpacl = NULL;
514 unsigned int flags = 0;
516 /* Get inode */
517 error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR);
518 if (error)
519 return error;
521 dentry = fhp->fh_dentry;
522 inode = dentry->d_inode;
523 if (S_ISDIR(inode->i_mode))
524 flags = NFS4_ACL_DIR;
526 host_error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags);
527 if (host_error == -EINVAL) {
528 return nfserr_attrnotsupp;
529 } else if (host_error < 0)
530 goto out_nfserr;
532 host_error = set_nfsv4_acl_one(dentry, pacl, POSIX_ACL_XATTR_ACCESS);
533 if (host_error < 0)
534 goto out_release;
536 if (S_ISDIR(inode->i_mode))
537 host_error = set_nfsv4_acl_one(dentry, dpacl, POSIX_ACL_XATTR_DEFAULT);
539 out_release:
540 posix_acl_release(pacl);
541 posix_acl_release(dpacl);
542 out_nfserr:
543 if (host_error == -EOPNOTSUPP)
544 return nfserr_attrnotsupp;
545 else
546 return nfserrno(host_error);
549 static struct posix_acl *
550 _get_posix_acl(struct dentry *dentry, char *key)
552 void *buf = NULL;
553 struct posix_acl *pacl = NULL;
554 int buflen;
556 buflen = nfsd_getxattr(dentry, key, &buf);
557 if (!buflen)
558 buflen = -ENODATA;
559 if (buflen <= 0)
560 return ERR_PTR(buflen);
562 pacl = posix_acl_from_xattr(buf, buflen);
563 kfree(buf);
564 return pacl;
568 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl)
570 struct inode *inode = dentry->d_inode;
571 int error = 0;
572 struct posix_acl *pacl = NULL, *dpacl = NULL;
573 unsigned int flags = 0;
575 pacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_ACCESS);
576 if (IS_ERR(pacl) && PTR_ERR(pacl) == -ENODATA)
577 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
578 if (IS_ERR(pacl)) {
579 error = PTR_ERR(pacl);
580 pacl = NULL;
581 goto out;
584 if (S_ISDIR(inode->i_mode)) {
585 dpacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_DEFAULT);
586 if (IS_ERR(dpacl) && PTR_ERR(dpacl) == -ENODATA)
587 dpacl = NULL;
588 else if (IS_ERR(dpacl)) {
589 error = PTR_ERR(dpacl);
590 dpacl = NULL;
591 goto out;
593 flags = NFS4_ACL_DIR;
596 *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags);
597 if (IS_ERR(*acl)) {
598 error = PTR_ERR(*acl);
599 *acl = NULL;
601 out:
602 posix_acl_release(pacl);
603 posix_acl_release(dpacl);
604 return error;
607 #endif /* defined(CONFIG_NFS_V4) */
609 #ifdef CONFIG_NFSD_V3
611 * Check server access rights to a file system object
613 struct accessmap {
614 u32 access;
615 int how;
617 static struct accessmap nfs3_regaccess[] = {
618 { NFS3_ACCESS_READ, NFSD_MAY_READ },
619 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
620 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC },
621 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE },
623 { 0, 0 }
626 static struct accessmap nfs3_diraccess[] = {
627 { NFS3_ACCESS_READ, NFSD_MAY_READ },
628 { NFS3_ACCESS_LOOKUP, NFSD_MAY_EXEC },
629 { NFS3_ACCESS_MODIFY, NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC},
630 { NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE },
631 { NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE },
633 { 0, 0 }
636 static struct accessmap nfs3_anyaccess[] = {
637 /* Some clients - Solaris 2.6 at least, make an access call
638 * to the server to check for access for things like /dev/null
639 * (which really, the server doesn't care about). So
640 * We provide simple access checking for them, looking
641 * mainly at mode bits, and we make sure to ignore read-only
642 * filesystem checks
644 { NFS3_ACCESS_READ, NFSD_MAY_READ },
645 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
646 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
647 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
649 { 0, 0 }
652 __be32
653 nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported)
655 struct accessmap *map;
656 struct svc_export *export;
657 struct dentry *dentry;
658 u32 query, result = 0, sresult = 0;
659 __be32 error;
661 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
662 if (error)
663 goto out;
665 export = fhp->fh_export;
666 dentry = fhp->fh_dentry;
668 if (S_ISREG(dentry->d_inode->i_mode))
669 map = nfs3_regaccess;
670 else if (S_ISDIR(dentry->d_inode->i_mode))
671 map = nfs3_diraccess;
672 else
673 map = nfs3_anyaccess;
676 query = *access;
677 for (; map->access; map++) {
678 if (map->access & query) {
679 __be32 err2;
681 sresult |= map->access;
683 err2 = nfsd_permission(rqstp, export, dentry, map->how);
684 switch (err2) {
685 case nfs_ok:
686 result |= map->access;
687 break;
689 /* the following error codes just mean the access was not allowed,
690 * rather than an error occurred */
691 case nfserr_rofs:
692 case nfserr_acces:
693 case nfserr_perm:
694 /* simply don't "or" in the access bit. */
695 break;
696 default:
697 error = err2;
698 goto out;
702 *access = result;
703 if (supported)
704 *supported = sresult;
706 out:
707 return error;
709 #endif /* CONFIG_NFSD_V3 */
714 * Open an existing file or directory.
715 * The access argument indicates the type of open (read/write/lock)
716 * N.B. After this call fhp needs an fh_put
718 __be32
719 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
720 int access, struct file **filp)
722 struct dentry *dentry;
723 struct inode *inode;
724 int flags = O_RDONLY|O_LARGEFILE;
725 __be32 err;
726 int host_err;
728 validate_process_creds();
731 * If we get here, then the client has already done an "open",
732 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
733 * in case a chmod has now revoked permission.
735 err = fh_verify(rqstp, fhp, type, access | NFSD_MAY_OWNER_OVERRIDE);
736 if (err)
737 goto out;
739 dentry = fhp->fh_dentry;
740 inode = dentry->d_inode;
742 /* Disallow write access to files with the append-only bit set
743 * or any access when mandatory locking enabled
745 err = nfserr_perm;
746 if (IS_APPEND(inode) && (access & NFSD_MAY_WRITE))
747 goto out;
749 * We must ignore files (but only files) which might have mandatory
750 * locks on them because there is no way to know if the accesser has
751 * the lock.
753 if (S_ISREG((inode)->i_mode) && mandatory_lock(inode))
754 goto out;
756 if (!inode->i_fop)
757 goto out;
760 * Check to see if there are any leases on this file.
761 * This may block while leases are broken.
763 host_err = break_lease(inode, O_NONBLOCK | ((access & NFSD_MAY_WRITE) ? O_WRONLY : 0));
764 if (host_err == -EWOULDBLOCK)
765 host_err = -ETIMEDOUT;
766 if (host_err) /* NOMEM or WOULDBLOCK */
767 goto out_nfserr;
769 if (access & NFSD_MAY_WRITE) {
770 if (access & NFSD_MAY_READ)
771 flags = O_RDWR|O_LARGEFILE;
772 else
773 flags = O_WRONLY|O_LARGEFILE;
775 *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
776 flags, current_cred());
777 if (IS_ERR(*filp))
778 host_err = PTR_ERR(*filp);
779 else
780 host_err = ima_file_check(*filp, access);
781 out_nfserr:
782 err = nfserrno(host_err);
783 out:
784 validate_process_creds();
785 return err;
789 * Close a file.
791 void
792 nfsd_close(struct file *filp)
794 fput(filp);
798 * Obtain the readahead parameters for the file
799 * specified by (dev, ino).
802 static inline struct raparms *
803 nfsd_get_raparms(dev_t dev, ino_t ino)
805 struct raparms *ra, **rap, **frap = NULL;
806 int depth = 0;
807 unsigned int hash;
808 struct raparm_hbucket *rab;
810 hash = jhash_2words(dev, ino, 0xfeedbeef) & RAPARM_HASH_MASK;
811 rab = &raparm_hash[hash];
813 spin_lock(&rab->pb_lock);
814 for (rap = &rab->pb_head; (ra = *rap); rap = &ra->p_next) {
815 if (ra->p_ino == ino && ra->p_dev == dev)
816 goto found;
817 depth++;
818 if (ra->p_count == 0)
819 frap = rap;
821 depth = nfsdstats.ra_size*11/10;
822 if (!frap) {
823 spin_unlock(&rab->pb_lock);
824 return NULL;
826 rap = frap;
827 ra = *frap;
828 ra->p_dev = dev;
829 ra->p_ino = ino;
830 ra->p_set = 0;
831 ra->p_hindex = hash;
832 found:
833 if (rap != &rab->pb_head) {
834 *rap = ra->p_next;
835 ra->p_next = rab->pb_head;
836 rab->pb_head = ra;
838 ra->p_count++;
839 nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++;
840 spin_unlock(&rab->pb_lock);
841 return ra;
845 * Grab and keep cached pages associated with a file in the svc_rqst
846 * so that they can be passed to the network sendmsg/sendpage routines
847 * directly. They will be released after the sending has completed.
849 static int
850 nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
851 struct splice_desc *sd)
853 struct svc_rqst *rqstp = sd->u.data;
854 struct page **pp = rqstp->rq_respages + rqstp->rq_resused;
855 struct page *page = buf->page;
856 size_t size;
857 int ret;
859 ret = buf->ops->confirm(pipe, buf);
860 if (unlikely(ret))
861 return ret;
863 size = sd->len;
865 if (rqstp->rq_res.page_len == 0) {
866 get_page(page);
867 put_page(*pp);
868 *pp = page;
869 rqstp->rq_resused++;
870 rqstp->rq_res.page_base = buf->offset;
871 rqstp->rq_res.page_len = size;
872 } else if (page != pp[-1]) {
873 get_page(page);
874 if (*pp)
875 put_page(*pp);
876 *pp = page;
877 rqstp->rq_resused++;
878 rqstp->rq_res.page_len += size;
879 } else
880 rqstp->rq_res.page_len += size;
882 return size;
885 static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
886 struct splice_desc *sd)
888 return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
891 static inline int svc_msnfs(struct svc_fh *ffhp)
893 #ifdef MSNFS
894 return (ffhp->fh_export->ex_flags & NFSEXP_MSNFS);
895 #else
896 return 0;
897 #endif
900 static __be32
901 nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
902 loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
904 struct inode *inode;
905 struct raparms *ra;
906 mm_segment_t oldfs;
907 __be32 err;
908 int host_err;
910 err = nfserr_perm;
911 inode = file->f_path.dentry->d_inode;
913 if (svc_msnfs(fhp) && !lock_may_read(inode, offset, *count))
914 goto out;
916 /* Get readahead parameters */
917 ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
919 if (ra && ra->p_set)
920 file->f_ra = ra->p_ra;
922 if (file->f_op->splice_read && rqstp->rq_splice_ok) {
923 struct splice_desc sd = {
924 .len = 0,
925 .total_len = *count,
926 .pos = offset,
927 .u.data = rqstp,
930 rqstp->rq_resused = 1;
931 host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
932 } else {
933 oldfs = get_fs();
934 set_fs(KERNEL_DS);
935 host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
936 set_fs(oldfs);
939 /* Write back readahead params */
940 if (ra) {
941 struct raparm_hbucket *rab = &raparm_hash[ra->p_hindex];
942 spin_lock(&rab->pb_lock);
943 ra->p_ra = file->f_ra;
944 ra->p_set = 1;
945 ra->p_count--;
946 spin_unlock(&rab->pb_lock);
949 if (host_err >= 0) {
950 nfsdstats.io_read += host_err;
951 *count = host_err;
952 err = 0;
953 fsnotify_access(file->f_path.dentry);
954 } else
955 err = nfserrno(host_err);
956 out:
957 return err;
960 static void kill_suid(struct dentry *dentry)
962 struct iattr ia;
963 ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
965 mutex_lock(&dentry->d_inode->i_mutex);
966 notify_change(dentry, &ia);
967 mutex_unlock(&dentry->d_inode->i_mutex);
971 * Gathered writes: If another process is currently writing to the file,
972 * there's a high chance this is another nfsd (triggered by a bulk write
973 * from a client's biod). Rather than syncing the file with each write
974 * request, we sleep for 10 msec.
976 * I don't know if this roughly approximates C. Juszak's idea of
977 * gathered writes, but it's a nice and simple solution (IMHO), and it
978 * seems to work:-)
980 * Note: we do this only in the NFSv2 case, since v3 and higher have a
981 * better tool (separate unstable writes and commits) for solving this
982 * problem.
984 static int wait_for_concurrent_writes(struct file *file)
986 struct inode *inode = file->f_path.dentry->d_inode;
987 static ino_t last_ino;
988 static dev_t last_dev;
989 int err = 0;
991 if (atomic_read(&inode->i_writecount) > 1
992 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
993 dprintk("nfsd: write defer %d\n", task_pid_nr(current));
994 msleep(10);
995 dprintk("nfsd: write resume %d\n", task_pid_nr(current));
998 if (inode->i_state & I_DIRTY) {
999 dprintk("nfsd: write sync %d\n", task_pid_nr(current));
1000 err = vfs_fsync(file, file->f_path.dentry, 0);
1002 last_ino = inode->i_ino;
1003 last_dev = inode->i_sb->s_dev;
1004 return err;
1007 static __be32
1008 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1009 loff_t offset, struct kvec *vec, int vlen,
1010 unsigned long *cnt, int *stablep)
1012 struct svc_export *exp;
1013 struct dentry *dentry;
1014 struct inode *inode;
1015 mm_segment_t oldfs;
1016 __be32 err = 0;
1017 int host_err;
1018 int stable = *stablep;
1019 int use_wgather;
1021 #ifdef MSNFS
1022 err = nfserr_perm;
1024 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1025 (!lock_may_write(file->f_path.dentry->d_inode, offset, *cnt)))
1026 goto out;
1027 #endif
1029 dentry = file->f_path.dentry;
1030 inode = dentry->d_inode;
1031 exp = fhp->fh_export;
1034 * Request sync writes if
1035 * - the sync export option has been set, or
1036 * - the client requested O_SYNC behavior (NFSv3 feature).
1037 * - The file system doesn't support fsync().
1038 * When NFSv2 gathered writes have been configured for this volume,
1039 * flushing the data to disk is handled separately below.
1041 use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
1043 if (!file->f_op->fsync) {/* COMMIT3 cannot work */
1044 stable = 2;
1045 *stablep = 2; /* FILE_SYNC */
1048 if (!EX_ISSYNC(exp))
1049 stable = 0;
1050 if (stable && !use_wgather) {
1051 spin_lock(&file->f_lock);
1052 file->f_flags |= O_SYNC;
1053 spin_unlock(&file->f_lock);
1056 /* Write the data. */
1057 oldfs = get_fs(); set_fs(KERNEL_DS);
1058 host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset);
1059 set_fs(oldfs);
1060 if (host_err < 0)
1061 goto out_nfserr;
1062 *cnt = host_err;
1063 nfsdstats.io_write += host_err;
1064 fsnotify_modify(file->f_path.dentry);
1066 /* clear setuid/setgid flag after write */
1067 if (inode->i_mode & (S_ISUID | S_ISGID))
1068 kill_suid(dentry);
1070 if (stable && use_wgather)
1071 host_err = wait_for_concurrent_writes(file);
1073 out_nfserr:
1074 dprintk("nfsd: write complete host_err=%d\n", host_err);
1075 if (host_err >= 0)
1076 err = 0;
1077 else
1078 err = nfserrno(host_err);
1079 out:
1080 return err;
1084 * Read data from a file. count must contain the requested read count
1085 * on entry. On return, *count contains the number of bytes actually read.
1086 * N.B. After this call fhp needs an fh_put
1088 __be32
1089 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1090 loff_t offset, struct kvec *vec, int vlen,
1091 unsigned long *count)
1093 __be32 err;
1095 if (file) {
1096 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1097 NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
1098 if (err)
1099 goto out;
1100 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1101 } else {
1102 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
1103 if (err)
1104 goto out;
1105 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1106 nfsd_close(file);
1108 out:
1109 return err;
1113 * Write data to a file.
1114 * The stable flag requests synchronous writes.
1115 * N.B. After this call fhp needs an fh_put
1117 __be32
1118 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1119 loff_t offset, struct kvec *vec, int vlen, unsigned long *cnt,
1120 int *stablep)
1122 __be32 err = 0;
1124 if (file) {
1125 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1126 NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE);
1127 if (err)
1128 goto out;
1129 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt,
1130 stablep);
1131 } else {
1132 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
1133 if (err)
1134 goto out;
1136 if (cnt)
1137 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen,
1138 cnt, stablep);
1139 nfsd_close(file);
1141 out:
1142 return err;
1145 #ifdef CONFIG_NFSD_V3
1147 * Commit all pending writes to stable storage.
1149 * Note: we only guarantee that data that lies within the range specified
1150 * by the 'offset' and 'count' parameters will be synced.
1152 * Unfortunately we cannot lock the file to make sure we return full WCC
1153 * data to the client, as locking happens lower down in the filesystem.
1155 __be32
1156 nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
1157 loff_t offset, unsigned long count)
1159 struct file *file;
1160 loff_t end = LLONG_MAX;
1161 __be32 err = nfserr_inval;
1163 if (offset < 0)
1164 goto out;
1165 if (count != 0) {
1166 end = offset + (loff_t)count - 1;
1167 if (end < offset)
1168 goto out;
1171 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
1172 if (err)
1173 goto out;
1174 if (EX_ISSYNC(fhp->fh_export)) {
1175 int err2 = vfs_fsync_range(file, file->f_path.dentry,
1176 offset, end, 0);
1178 if (err2 != -EINVAL)
1179 err = nfserrno(err2);
1180 else
1181 err = nfserr_notsupp;
1184 nfsd_close(file);
1185 out:
1186 return err;
1188 #endif /* CONFIG_NFSD_V3 */
1190 static __be32
1191 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
1192 struct iattr *iap)
1195 * Mode has already been set earlier in create:
1197 iap->ia_valid &= ~ATTR_MODE;
1199 * Setting uid/gid works only for root. Irix appears to
1200 * send along the gid on create when it tries to implement
1201 * setgid directories via NFS:
1203 if (current_fsuid() != 0)
1204 iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
1205 if (iap->ia_valid)
1206 return nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
1207 return 0;
1210 /* HPUX client sometimes creates a file in mode 000, and sets size to 0.
1211 * setting size to 0 may fail for some specific file systems by the permission
1212 * checking which requires WRITE permission but the mode is 000.
1213 * we ignore the resizing(to 0) on the just new created file, since the size is
1214 * 0 after file created.
1216 * call this only after vfs_create() is called.
1217 * */
1218 static void
1219 nfsd_check_ignore_resizing(struct iattr *iap)
1221 if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
1222 iap->ia_valid &= ~ATTR_SIZE;
1226 * Create a file (regular, directory, device, fifo); UNIX sockets
1227 * not yet implemented.
1228 * If the response fh has been verified, the parent directory should
1229 * already be locked. Note that the parent directory is left locked.
1231 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1233 __be32
1234 nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1235 char *fname, int flen, struct iattr *iap,
1236 int type, dev_t rdev, struct svc_fh *resfhp)
1238 struct dentry *dentry, *dchild = NULL;
1239 struct inode *dirp;
1240 __be32 err;
1241 __be32 err2;
1242 int host_err;
1244 err = nfserr_perm;
1245 if (!flen)
1246 goto out;
1247 err = nfserr_exist;
1248 if (isdotent(fname, flen))
1249 goto out;
1251 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1252 if (err)
1253 goto out;
1255 dentry = fhp->fh_dentry;
1256 dirp = dentry->d_inode;
1258 err = nfserr_notdir;
1259 if (!dirp->i_op->lookup)
1260 goto out;
1262 * Check whether the response file handle has been verified yet.
1263 * If it has, the parent directory should already be locked.
1265 if (!resfhp->fh_dentry) {
1266 /* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */
1267 fh_lock_nested(fhp, I_MUTEX_PARENT);
1268 dchild = lookup_one_len(fname, dentry, flen);
1269 host_err = PTR_ERR(dchild);
1270 if (IS_ERR(dchild))
1271 goto out_nfserr;
1272 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1273 if (err)
1274 goto out;
1275 } else {
1276 /* called from nfsd_proc_create */
1277 dchild = dget(resfhp->fh_dentry);
1278 if (!fhp->fh_locked) {
1279 /* not actually possible */
1280 printk(KERN_ERR
1281 "nfsd_create: parent %s/%s not locked!\n",
1282 dentry->d_parent->d_name.name,
1283 dentry->d_name.name);
1284 err = nfserr_io;
1285 goto out;
1289 * Make sure the child dentry is still negative ...
1291 err = nfserr_exist;
1292 if (dchild->d_inode) {
1293 dprintk("nfsd_create: dentry %s/%s not negative!\n",
1294 dentry->d_name.name, dchild->d_name.name);
1295 goto out;
1298 if (!(iap->ia_valid & ATTR_MODE))
1299 iap->ia_mode = 0;
1300 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
1302 err = nfserr_inval;
1303 if (!S_ISREG(type) && !S_ISDIR(type) && !special_file(type)) {
1304 printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
1305 type);
1306 goto out;
1309 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1310 if (host_err)
1311 goto out_nfserr;
1314 * Get the dir op function pointer.
1316 err = 0;
1317 switch (type) {
1318 case S_IFREG:
1319 host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1320 if (!host_err)
1321 nfsd_check_ignore_resizing(iap);
1322 break;
1323 case S_IFDIR:
1324 host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
1325 break;
1326 case S_IFCHR:
1327 case S_IFBLK:
1328 case S_IFIFO:
1329 case S_IFSOCK:
1330 host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
1331 break;
1333 if (host_err < 0) {
1334 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1335 goto out_nfserr;
1338 err = nfsd_create_setattr(rqstp, resfhp, iap);
1341 * nfsd_setattr already committed the child. Transactional filesystems
1342 * had a chance to commit changes for both parent and child
1343 * simultaneously making the following commit_metadata a noop.
1345 err2 = nfserrno(commit_metadata(fhp));
1346 if (err2)
1347 err = err2;
1348 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1350 * Update the file handle to get the new inode info.
1352 if (!err)
1353 err = fh_update(resfhp);
1354 out:
1355 if (dchild && !IS_ERR(dchild))
1356 dput(dchild);
1357 return err;
1359 out_nfserr:
1360 err = nfserrno(host_err);
1361 goto out;
1364 #ifdef CONFIG_NFSD_V3
1366 * NFSv3 version of nfsd_create
1368 __be32
1369 nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
1370 char *fname, int flen, struct iattr *iap,
1371 struct svc_fh *resfhp, int createmode, u32 *verifier,
1372 int *truncp, int *created)
1374 struct dentry *dentry, *dchild = NULL;
1375 struct inode *dirp;
1376 __be32 err;
1377 int host_err;
1378 __u32 v_mtime=0, v_atime=0;
1380 err = nfserr_perm;
1381 if (!flen)
1382 goto out;
1383 err = nfserr_exist;
1384 if (isdotent(fname, flen))
1385 goto out;
1386 if (!(iap->ia_valid & ATTR_MODE))
1387 iap->ia_mode = 0;
1388 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1389 if (err)
1390 goto out;
1392 dentry = fhp->fh_dentry;
1393 dirp = dentry->d_inode;
1395 /* Get all the sanity checks out of the way before
1396 * we lock the parent. */
1397 err = nfserr_notdir;
1398 if (!dirp->i_op->lookup)
1399 goto out;
1400 fh_lock_nested(fhp, I_MUTEX_PARENT);
1403 * Compose the response file handle.
1405 dchild = lookup_one_len(fname, dentry, flen);
1406 host_err = PTR_ERR(dchild);
1407 if (IS_ERR(dchild))
1408 goto out_nfserr;
1410 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1411 if (err)
1412 goto out;
1414 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1415 /* solaris7 gets confused (bugid 4218508) if these have
1416 * the high bit set, so just clear the high bits. If this is
1417 * ever changed to use different attrs for storing the
1418 * verifier, then do_open_lookup() will also need to be fixed
1419 * accordingly.
1421 v_mtime = verifier[0]&0x7fffffff;
1422 v_atime = verifier[1]&0x7fffffff;
1425 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1426 if (host_err)
1427 goto out_nfserr;
1428 if (dchild->d_inode) {
1429 err = 0;
1431 switch (createmode) {
1432 case NFS3_CREATE_UNCHECKED:
1433 if (! S_ISREG(dchild->d_inode->i_mode))
1434 err = nfserr_exist;
1435 else if (truncp) {
1436 /* in nfsv4, we need to treat this case a little
1437 * differently. we don't want to truncate the
1438 * file now; this would be wrong if the OPEN
1439 * fails for some other reason. furthermore,
1440 * if the size is nonzero, we should ignore it
1441 * according to spec!
1443 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size;
1445 else {
1446 iap->ia_valid &= ATTR_SIZE;
1447 goto set_attr;
1449 break;
1450 case NFS3_CREATE_EXCLUSIVE:
1451 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime
1452 && dchild->d_inode->i_atime.tv_sec == v_atime
1453 && dchild->d_inode->i_size == 0 )
1454 break;
1455 /* fallthru */
1456 case NFS3_CREATE_GUARDED:
1457 err = nfserr_exist;
1459 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1460 goto out;
1463 host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1464 if (host_err < 0) {
1465 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1466 goto out_nfserr;
1468 if (created)
1469 *created = 1;
1471 nfsd_check_ignore_resizing(iap);
1473 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1474 /* Cram the verifier into atime/mtime */
1475 iap->ia_valid = ATTR_MTIME|ATTR_ATIME
1476 | ATTR_MTIME_SET|ATTR_ATIME_SET;
1477 /* XXX someone who knows this better please fix it for nsec */
1478 iap->ia_mtime.tv_sec = v_mtime;
1479 iap->ia_atime.tv_sec = v_atime;
1480 iap->ia_mtime.tv_nsec = 0;
1481 iap->ia_atime.tv_nsec = 0;
1484 set_attr:
1485 err = nfsd_create_setattr(rqstp, resfhp, iap);
1488 * nfsd_setattr already committed the child (and possibly also the parent).
1490 if (!err)
1491 err = nfserrno(commit_metadata(fhp));
1493 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1495 * Update the filehandle to get the new inode info.
1497 if (!err)
1498 err = fh_update(resfhp);
1500 out:
1501 fh_unlock(fhp);
1502 if (dchild && !IS_ERR(dchild))
1503 dput(dchild);
1504 return err;
1506 out_nfserr:
1507 err = nfserrno(host_err);
1508 goto out;
1510 #endif /* CONFIG_NFSD_V3 */
1513 * Read a symlink. On entry, *lenp must contain the maximum path length that
1514 * fits into the buffer. On return, it contains the true length.
1515 * N.B. After this call fhp needs an fh_put
1517 __be32
1518 nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
1520 struct dentry *dentry;
1521 struct inode *inode;
1522 mm_segment_t oldfs;
1523 __be32 err;
1524 int host_err;
1526 err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
1527 if (err)
1528 goto out;
1530 dentry = fhp->fh_dentry;
1531 inode = dentry->d_inode;
1533 err = nfserr_inval;
1534 if (!inode->i_op->readlink)
1535 goto out;
1537 touch_atime(fhp->fh_export->ex_path.mnt, dentry);
1538 /* N.B. Why does this call need a get_fs()??
1539 * Remove the set_fs and watch the fireworks:-) --okir
1542 oldfs = get_fs(); set_fs(KERNEL_DS);
1543 host_err = inode->i_op->readlink(dentry, buf, *lenp);
1544 set_fs(oldfs);
1546 if (host_err < 0)
1547 goto out_nfserr;
1548 *lenp = host_err;
1549 err = 0;
1550 out:
1551 return err;
1553 out_nfserr:
1554 err = nfserrno(host_err);
1555 goto out;
1559 * Create a symlink and look up its inode
1560 * N.B. After this call _both_ fhp and resfhp need an fh_put
1562 __be32
1563 nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
1564 char *fname, int flen,
1565 char *path, int plen,
1566 struct svc_fh *resfhp,
1567 struct iattr *iap)
1569 struct dentry *dentry, *dnew;
1570 __be32 err, cerr;
1571 int host_err;
1573 err = nfserr_noent;
1574 if (!flen || !plen)
1575 goto out;
1576 err = nfserr_exist;
1577 if (isdotent(fname, flen))
1578 goto out;
1580 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1581 if (err)
1582 goto out;
1583 fh_lock(fhp);
1584 dentry = fhp->fh_dentry;
1585 dnew = lookup_one_len(fname, dentry, flen);
1586 host_err = PTR_ERR(dnew);
1587 if (IS_ERR(dnew))
1588 goto out_nfserr;
1590 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1591 if (host_err)
1592 goto out_nfserr;
1594 if (unlikely(path[plen] != 0)) {
1595 char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
1596 if (path_alloced == NULL)
1597 host_err = -ENOMEM;
1598 else {
1599 strncpy(path_alloced, path, plen);
1600 path_alloced[plen] = 0;
1601 host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced);
1602 kfree(path_alloced);
1604 } else
1605 host_err = vfs_symlink(dentry->d_inode, dnew, path);
1606 err = nfserrno(host_err);
1607 if (!err)
1608 err = nfserrno(commit_metadata(fhp));
1609 fh_unlock(fhp);
1611 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1613 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
1614 dput(dnew);
1615 if (err==0) err = cerr;
1616 out:
1617 return err;
1619 out_nfserr:
1620 err = nfserrno(host_err);
1621 goto out;
1625 * Create a hardlink
1626 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1628 __be32
1629 nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
1630 char *name, int len, struct svc_fh *tfhp)
1632 struct dentry *ddir, *dnew, *dold;
1633 struct inode *dirp, *dest;
1634 __be32 err;
1635 int host_err;
1637 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
1638 if (err)
1639 goto out;
1640 err = fh_verify(rqstp, tfhp, -S_IFDIR, NFSD_MAY_NOP);
1641 if (err)
1642 goto out;
1644 err = nfserr_perm;
1645 if (!len)
1646 goto out;
1647 err = nfserr_exist;
1648 if (isdotent(name, len))
1649 goto out;
1651 fh_lock_nested(ffhp, I_MUTEX_PARENT);
1652 ddir = ffhp->fh_dentry;
1653 dirp = ddir->d_inode;
1655 dnew = lookup_one_len(name, ddir, len);
1656 host_err = PTR_ERR(dnew);
1657 if (IS_ERR(dnew))
1658 goto out_nfserr;
1660 dold = tfhp->fh_dentry;
1661 dest = dold->d_inode;
1663 host_err = mnt_want_write(tfhp->fh_export->ex_path.mnt);
1664 if (host_err) {
1665 err = nfserrno(host_err);
1666 goto out_dput;
1668 host_err = vfs_link(dold, dirp, dnew);
1669 if (!host_err) {
1670 err = nfserrno(commit_metadata(ffhp));
1671 if (!err)
1672 err = nfserrno(commit_metadata(tfhp));
1673 } else {
1674 if (host_err == -EXDEV && rqstp->rq_vers == 2)
1675 err = nfserr_acces;
1676 else
1677 err = nfserrno(host_err);
1679 mnt_drop_write(tfhp->fh_export->ex_path.mnt);
1680 out_dput:
1681 dput(dnew);
1682 out_unlock:
1683 fh_unlock(ffhp);
1684 out:
1685 return err;
1687 out_nfserr:
1688 err = nfserrno(host_err);
1689 goto out_unlock;
1693 * Rename a file
1694 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1696 __be32
1697 nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
1698 struct svc_fh *tfhp, char *tname, int tlen)
1700 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
1701 struct inode *fdir, *tdir;
1702 __be32 err;
1703 int host_err;
1705 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
1706 if (err)
1707 goto out;
1708 err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
1709 if (err)
1710 goto out;
1712 fdentry = ffhp->fh_dentry;
1713 fdir = fdentry->d_inode;
1715 tdentry = tfhp->fh_dentry;
1716 tdir = tdentry->d_inode;
1718 err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
1719 if (ffhp->fh_export != tfhp->fh_export)
1720 goto out;
1722 err = nfserr_perm;
1723 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
1724 goto out;
1726 /* cannot use fh_lock as we need deadlock protective ordering
1727 * so do it by hand */
1728 trap = lock_rename(tdentry, fdentry);
1729 ffhp->fh_locked = tfhp->fh_locked = 1;
1730 fill_pre_wcc(ffhp);
1731 fill_pre_wcc(tfhp);
1733 odentry = lookup_one_len(fname, fdentry, flen);
1734 host_err = PTR_ERR(odentry);
1735 if (IS_ERR(odentry))
1736 goto out_nfserr;
1738 host_err = -ENOENT;
1739 if (!odentry->d_inode)
1740 goto out_dput_old;
1741 host_err = -EINVAL;
1742 if (odentry == trap)
1743 goto out_dput_old;
1745 ndentry = lookup_one_len(tname, tdentry, tlen);
1746 host_err = PTR_ERR(ndentry);
1747 if (IS_ERR(ndentry))
1748 goto out_dput_old;
1749 host_err = -ENOTEMPTY;
1750 if (ndentry == trap)
1751 goto out_dput_new;
1753 if (svc_msnfs(ffhp) &&
1754 ((atomic_read(&odentry->d_count) > 1)
1755 || (atomic_read(&ndentry->d_count) > 1))) {
1756 host_err = -EPERM;
1757 goto out_dput_new;
1760 host_err = -EXDEV;
1761 if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
1762 goto out_dput_new;
1763 host_err = mnt_want_write(ffhp->fh_export->ex_path.mnt);
1764 if (host_err)
1765 goto out_dput_new;
1767 host_err = vfs_rename(fdir, odentry, tdir, ndentry);
1768 if (!host_err) {
1769 host_err = commit_metadata(tfhp);
1770 if (!host_err)
1771 host_err = commit_metadata(ffhp);
1774 mnt_drop_write(ffhp->fh_export->ex_path.mnt);
1776 out_dput_new:
1777 dput(ndentry);
1778 out_dput_old:
1779 dput(odentry);
1780 out_nfserr:
1781 err = nfserrno(host_err);
1783 /* we cannot reply on fh_unlock on the two filehandles,
1784 * as that would do the wrong thing if the two directories
1785 * were the same, so again we do it by hand
1787 fill_post_wcc(ffhp);
1788 fill_post_wcc(tfhp);
1789 unlock_rename(tdentry, fdentry);
1790 ffhp->fh_locked = tfhp->fh_locked = 0;
1792 out:
1793 return err;
1797 * Unlink a file or directory
1798 * N.B. After this call fhp needs an fh_put
1800 __be32
1801 nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
1802 char *fname, int flen)
1804 struct dentry *dentry, *rdentry;
1805 struct inode *dirp;
1806 __be32 err;
1807 int host_err;
1809 err = nfserr_acces;
1810 if (!flen || isdotent(fname, flen))
1811 goto out;
1812 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
1813 if (err)
1814 goto out;
1816 fh_lock_nested(fhp, I_MUTEX_PARENT);
1817 dentry = fhp->fh_dentry;
1818 dirp = dentry->d_inode;
1820 rdentry = lookup_one_len(fname, dentry, flen);
1821 host_err = PTR_ERR(rdentry);
1822 if (IS_ERR(rdentry))
1823 goto out_nfserr;
1825 if (!rdentry->d_inode) {
1826 dput(rdentry);
1827 err = nfserr_noent;
1828 goto out;
1831 if (!type)
1832 type = rdentry->d_inode->i_mode & S_IFMT;
1834 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1835 if (host_err)
1836 goto out_nfserr;
1838 if (type != S_IFDIR) { /* It's UNLINK */
1839 #ifdef MSNFS
1840 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1841 (atomic_read(&rdentry->d_count) > 1)) {
1842 host_err = -EPERM;
1843 } else
1844 #endif
1845 host_err = vfs_unlink(dirp, rdentry);
1846 } else { /* It's RMDIR */
1847 host_err = vfs_rmdir(dirp, rdentry);
1850 dput(rdentry);
1852 if (!host_err)
1853 host_err = commit_metadata(fhp);
1855 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1856 out_nfserr:
1857 err = nfserrno(host_err);
1858 out:
1859 return err;
1863 * We do this buffering because we must not call back into the file
1864 * system's ->lookup() method from the filldir callback. That may well
1865 * deadlock a number of file systems.
1867 * This is based heavily on the implementation of same in XFS.
1869 struct buffered_dirent {
1870 u64 ino;
1871 loff_t offset;
1872 int namlen;
1873 unsigned int d_type;
1874 char name[];
1877 struct readdir_data {
1878 char *dirent;
1879 size_t used;
1880 int full;
1883 static int nfsd_buffered_filldir(void *__buf, const char *name, int namlen,
1884 loff_t offset, u64 ino, unsigned int d_type)
1886 struct readdir_data *buf = __buf;
1887 struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
1888 unsigned int reclen;
1890 reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
1891 if (buf->used + reclen > PAGE_SIZE) {
1892 buf->full = 1;
1893 return -EINVAL;
1896 de->namlen = namlen;
1897 de->offset = offset;
1898 de->ino = ino;
1899 de->d_type = d_type;
1900 memcpy(de->name, name, namlen);
1901 buf->used += reclen;
1903 return 0;
1906 static __be32 nfsd_buffered_readdir(struct file *file, filldir_t func,
1907 struct readdir_cd *cdp, loff_t *offsetp)
1909 struct readdir_data buf;
1910 struct buffered_dirent *de;
1911 int host_err;
1912 int size;
1913 loff_t offset;
1915 buf.dirent = (void *)__get_free_page(GFP_KERNEL);
1916 if (!buf.dirent)
1917 return nfserrno(-ENOMEM);
1919 offset = *offsetp;
1921 while (1) {
1922 struct inode *dir_inode = file->f_path.dentry->d_inode;
1923 unsigned int reclen;
1925 cdp->err = nfserr_eof; /* will be cleared on successful read */
1926 buf.used = 0;
1927 buf.full = 0;
1929 host_err = vfs_readdir(file, nfsd_buffered_filldir, &buf);
1930 if (buf.full)
1931 host_err = 0;
1933 if (host_err < 0)
1934 break;
1936 size = buf.used;
1938 if (!size)
1939 break;
1942 * Various filldir functions may end up calling back into
1943 * lookup_one_len() and the file system's ->lookup() method.
1944 * These expect i_mutex to be held, as it would within readdir.
1946 host_err = mutex_lock_killable(&dir_inode->i_mutex);
1947 if (host_err)
1948 break;
1950 de = (struct buffered_dirent *)buf.dirent;
1951 while (size > 0) {
1952 offset = de->offset;
1954 if (func(cdp, de->name, de->namlen, de->offset,
1955 de->ino, de->d_type))
1956 break;
1958 if (cdp->err != nfs_ok)
1959 break;
1961 reclen = ALIGN(sizeof(*de) + de->namlen,
1962 sizeof(u64));
1963 size -= reclen;
1964 de = (struct buffered_dirent *)((char *)de + reclen);
1966 mutex_unlock(&dir_inode->i_mutex);
1967 if (size > 0) /* We bailed out early */
1968 break;
1970 offset = vfs_llseek(file, 0, SEEK_CUR);
1973 free_page((unsigned long)(buf.dirent));
1975 if (host_err)
1976 return nfserrno(host_err);
1978 *offsetp = offset;
1979 return cdp->err;
1983 * Read entries from a directory.
1984 * The NFSv3/4 verifier we ignore for now.
1986 __be32
1987 nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
1988 struct readdir_cd *cdp, filldir_t func)
1990 __be32 err;
1991 struct file *file;
1992 loff_t offset = *offsetp;
1994 err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file);
1995 if (err)
1996 goto out;
1998 offset = vfs_llseek(file, offset, 0);
1999 if (offset < 0) {
2000 err = nfserrno((int)offset);
2001 goto out_close;
2004 err = nfsd_buffered_readdir(file, func, cdp, offsetp);
2006 if (err == nfserr_eof || err == nfserr_toosmall)
2007 err = nfs_ok; /* can still be found in ->err */
2008 out_close:
2009 nfsd_close(file);
2010 out:
2011 return err;
2015 * Get file system stats
2016 * N.B. After this call fhp needs an fh_put
2018 __be32
2019 nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
2021 __be32 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
2022 if (!err && vfs_statfs(fhp->fh_dentry,stat))
2023 err = nfserr_io;
2024 return err;
2027 static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp)
2029 return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY;
2033 * Check for a user's access permissions to this inode.
2035 __be32
2036 nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
2037 struct dentry *dentry, int acc)
2039 struct inode *inode = dentry->d_inode;
2040 struct path path;
2041 int err;
2043 if (acc == NFSD_MAY_NOP)
2044 return 0;
2045 #if 0
2046 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
2047 acc,
2048 (acc & NFSD_MAY_READ)? " read" : "",
2049 (acc & NFSD_MAY_WRITE)? " write" : "",
2050 (acc & NFSD_MAY_EXEC)? " exec" : "",
2051 (acc & NFSD_MAY_SATTR)? " sattr" : "",
2052 (acc & NFSD_MAY_TRUNC)? " trunc" : "",
2053 (acc & NFSD_MAY_LOCK)? " lock" : "",
2054 (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
2055 inode->i_mode,
2056 IS_IMMUTABLE(inode)? " immut" : "",
2057 IS_APPEND(inode)? " append" : "",
2058 __mnt_is_readonly(exp->ex_path.mnt)? " ro" : "");
2059 dprintk(" owner %d/%d user %d/%d\n",
2060 inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
2061 #endif
2063 /* Normally we reject any write/sattr etc access on a read-only file
2064 * system. But if it is IRIX doing check on write-access for a
2065 * device special file, we ignore rofs.
2067 if (!(acc & NFSD_MAY_LOCAL_ACCESS))
2068 if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
2069 if (exp_rdonly(rqstp, exp) ||
2070 __mnt_is_readonly(exp->ex_path.mnt))
2071 return nfserr_rofs;
2072 if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode))
2073 return nfserr_perm;
2075 if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
2076 return nfserr_perm;
2078 if (acc & NFSD_MAY_LOCK) {
2079 /* If we cannot rely on authentication in NLM requests,
2080 * just allow locks, otherwise require read permission, or
2081 * ownership
2083 if (exp->ex_flags & NFSEXP_NOAUTHNLM)
2084 return 0;
2085 else
2086 acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
2089 * The file owner always gets access permission for accesses that
2090 * would normally be checked at open time. This is to make
2091 * file access work even when the client has done a fchmod(fd, 0).
2093 * However, `cp foo bar' should fail nevertheless when bar is
2094 * readonly. A sensible way to do this might be to reject all
2095 * attempts to truncate a read-only file, because a creat() call
2096 * always implies file truncation.
2097 * ... but this isn't really fair. A process may reasonably call
2098 * ftruncate on an open file descriptor on a file with perm 000.
2099 * We must trust the client to do permission checking - using "ACCESS"
2100 * with NFSv3.
2102 if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
2103 inode->i_uid == current_fsuid())
2104 return 0;
2106 /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
2107 err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
2109 /* Allow read access to binaries even when mode 111 */
2110 if (err == -EACCES && S_ISREG(inode->i_mode) &&
2111 acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE))
2112 err = inode_permission(inode, MAY_EXEC);
2113 if (err)
2114 goto nfsd_out;
2116 /* Do integrity (permission) checking now, but defer incrementing
2117 * IMA counts to the actual file open.
2119 path.mnt = exp->ex_path.mnt;
2120 path.dentry = dentry;
2121 nfsd_out:
2122 return err? nfserrno(err) : 0;
2125 void
2126 nfsd_racache_shutdown(void)
2128 struct raparms *raparm, *last_raparm;
2129 unsigned int i;
2131 dprintk("nfsd: freeing readahead buffers.\n");
2133 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2134 raparm = raparm_hash[i].pb_head;
2135 while(raparm) {
2136 last_raparm = raparm;
2137 raparm = raparm->p_next;
2138 kfree(last_raparm);
2140 raparm_hash[i].pb_head = NULL;
2144 * Initialize readahead param cache
2147 nfsd_racache_init(int cache_size)
2149 int i;
2150 int j = 0;
2151 int nperbucket;
2152 struct raparms **raparm = NULL;
2155 if (raparm_hash[0].pb_head)
2156 return 0;
2157 nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE);
2158 if (nperbucket < 2)
2159 nperbucket = 2;
2160 cache_size = nperbucket * RAPARM_HASH_SIZE;
2162 dprintk("nfsd: allocating %d readahead buffers.\n", cache_size);
2164 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2165 spin_lock_init(&raparm_hash[i].pb_lock);
2167 raparm = &raparm_hash[i].pb_head;
2168 for (j = 0; j < nperbucket; j++) {
2169 *raparm = kzalloc(sizeof(struct raparms), GFP_KERNEL);
2170 if (!*raparm)
2171 goto out_nomem;
2172 raparm = &(*raparm)->p_next;
2174 *raparm = NULL;
2177 nfsdstats.ra_size = cache_size;
2178 return 0;
2180 out_nomem:
2181 dprintk("nfsd: kmalloc failed, freeing readahead buffers\n");
2182 nfsd_racache_shutdown();
2183 return -ENOMEM;
2186 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
2187 struct posix_acl *
2188 nfsd_get_posix_acl(struct svc_fh *fhp, int type)
2190 struct inode *inode = fhp->fh_dentry->d_inode;
2191 char *name;
2192 void *value = NULL;
2193 ssize_t size;
2194 struct posix_acl *acl;
2196 if (!IS_POSIXACL(inode))
2197 return ERR_PTR(-EOPNOTSUPP);
2199 switch (type) {
2200 case ACL_TYPE_ACCESS:
2201 name = POSIX_ACL_XATTR_ACCESS;
2202 break;
2203 case ACL_TYPE_DEFAULT:
2204 name = POSIX_ACL_XATTR_DEFAULT;
2205 break;
2206 default:
2207 return ERR_PTR(-EOPNOTSUPP);
2210 size = nfsd_getxattr(fhp->fh_dentry, name, &value);
2211 if (size < 0)
2212 return ERR_PTR(size);
2214 acl = posix_acl_from_xattr(value, size);
2215 kfree(value);
2216 return acl;
2220 nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
2222 struct inode *inode = fhp->fh_dentry->d_inode;
2223 char *name;
2224 void *value = NULL;
2225 size_t size;
2226 int error;
2228 if (!IS_POSIXACL(inode) ||
2229 !inode->i_op->setxattr || !inode->i_op->removexattr)
2230 return -EOPNOTSUPP;
2231 switch(type) {
2232 case ACL_TYPE_ACCESS:
2233 name = POSIX_ACL_XATTR_ACCESS;
2234 break;
2235 case ACL_TYPE_DEFAULT:
2236 name = POSIX_ACL_XATTR_DEFAULT;
2237 break;
2238 default:
2239 return -EOPNOTSUPP;
2242 if (acl && acl->a_count) {
2243 size = posix_acl_xattr_size(acl->a_count);
2244 value = kmalloc(size, GFP_KERNEL);
2245 if (!value)
2246 return -ENOMEM;
2247 error = posix_acl_to_xattr(acl, value, size);
2248 if (error < 0)
2249 goto getout;
2250 size = error;
2251 } else
2252 size = 0;
2254 error = mnt_want_write(fhp->fh_export->ex_path.mnt);
2255 if (error)
2256 goto getout;
2257 if (size)
2258 error = vfs_setxattr(fhp->fh_dentry, name, value, size, 0);
2259 else {
2260 if (!S_ISDIR(inode->i_mode) && type == ACL_TYPE_DEFAULT)
2261 error = 0;
2262 else {
2263 error = vfs_removexattr(fhp->fh_dentry, name);
2264 if (error == -ENODATA)
2265 error = 0;
2268 mnt_drop_write(fhp->fh_export->ex_path.mnt);
2270 getout:
2271 kfree(value);
2272 return error;
2274 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */