2 * File operations used by nfsd. Some of these have been ripped from
3 * other parts of the kernel because they weren't exported, others
4 * are partial duplicates with added or changed functionality.
6 * Note that several functions dget() the dentry upon which they want
7 * to act, most notably those that create directory entries. Response
8 * dentry's are dput()'d if necessary in the release callback.
9 * So if you notice code paths that apparently fail to dput() the
10 * dentry, don't worry--they have been taken care of.
12 * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de>
13 * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp>
17 #include <linux/file.h>
18 #include <linux/splice.h>
19 #include <linux/falloc.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 <linux/slab.h>
29 #include <linux/uaccess.h>
30 #include <linux/exportfs.h>
31 #include <linux/writeback.h>
32 #include <linux/security.h>
36 #endif /* CONFIG_NFSD_V3 */
39 #include "../internal.h"
42 #endif /* CONFIG_NFSD_V4 */
48 #define NFSDDBG_FACILITY NFSDDBG_FILEOP
52 * This is a cache of readahead params that help us choose the proper
53 * readahead strategy. Initially, we set all readahead parameters to 0
54 * and let the VFS handle things.
55 * If you increase the number of cached files very much, you'll need to
56 * add a hash table here.
59 struct raparms
*p_next
;
64 struct file_ra_state p_ra
;
65 unsigned int p_hindex
;
68 struct raparm_hbucket
{
69 struct raparms
*pb_head
;
71 } ____cacheline_aligned_in_smp
;
73 #define RAPARM_HASH_BITS 4
74 #define RAPARM_HASH_SIZE (1<<RAPARM_HASH_BITS)
75 #define RAPARM_HASH_MASK (RAPARM_HASH_SIZE-1)
76 static struct raparm_hbucket raparm_hash
[RAPARM_HASH_SIZE
];
79 * Called from nfsd_lookup and encode_dirent. Check if we have crossed
81 * Returns -EAGAIN or -ETIMEDOUT leaving *dpp and *expp unchanged,
82 * or nfs_ok having possibly changed *dpp and *expp
85 nfsd_cross_mnt(struct svc_rqst
*rqstp
, struct dentry
**dpp
,
86 struct svc_export
**expp
)
88 struct svc_export
*exp
= *expp
, *exp2
= NULL
;
89 struct dentry
*dentry
= *dpp
;
90 struct path path
= {.mnt
= mntget(exp
->ex_path
.mnt
),
91 .dentry
= dget(dentry
)};
94 err
= follow_down(&path
);
98 exp2
= rqst_exp_get_by_name(rqstp
, &path
);
102 * We normally allow NFS clients to continue
103 * "underneath" a mountpoint that is not exported.
104 * The exception is V4ROOT, where no traversal is ever
105 * allowed without an explicit export of the new
108 if (err
== -ENOENT
&& !(exp
->ex_flags
& NFSEXP_V4ROOT
))
113 if (nfsd_v4client(rqstp
) ||
114 (exp
->ex_flags
& NFSEXP_CROSSMOUNT
) || EX_NOHIDE(exp2
)) {
115 /* successfully crossed mount point */
117 * This is subtle: path.dentry is *not* on path.mnt
118 * at this point. The only reason we are safe is that
119 * original mnt is pinned down by exp, so we should
120 * put path *before* putting exp
123 path
.dentry
= dentry
;
133 static void follow_to_parent(struct path
*path
)
137 while (path
->dentry
== path
->mnt
->mnt_root
&& follow_up(path
))
139 dp
= dget_parent(path
->dentry
);
144 static int nfsd_lookup_parent(struct svc_rqst
*rqstp
, struct dentry
*dparent
, struct svc_export
**exp
, struct dentry
**dentryp
)
146 struct svc_export
*exp2
;
147 struct path path
= {.mnt
= mntget((*exp
)->ex_path
.mnt
),
148 .dentry
= dget(dparent
)};
150 follow_to_parent(&path
);
152 exp2
= rqst_exp_parent(rqstp
, &path
);
153 if (PTR_ERR(exp2
) == -ENOENT
) {
154 *dentryp
= dget(dparent
);
155 } else if (IS_ERR(exp2
)) {
157 return PTR_ERR(exp2
);
159 *dentryp
= dget(path
.dentry
);
168 * For nfsd purposes, we treat V4ROOT exports as though there was an
169 * export at *every* directory.
171 int nfsd_mountpoint(struct dentry
*dentry
, struct svc_export
*exp
)
173 if (d_mountpoint(dentry
))
175 if (nfsd4_is_junction(dentry
))
177 if (!(exp
->ex_flags
& NFSEXP_V4ROOT
))
179 return d_inode(dentry
) != NULL
;
183 nfsd_lookup_dentry(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
184 const char *name
, unsigned int len
,
185 struct svc_export
**exp_ret
, struct dentry
**dentry_ret
)
187 struct svc_export
*exp
;
188 struct dentry
*dparent
;
189 struct dentry
*dentry
;
192 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp
), len
,name
);
194 dparent
= fhp
->fh_dentry
;
195 exp
= exp_get(fhp
->fh_export
);
197 /* Lookup the name, but don't follow links */
198 if (isdotent(name
, len
)) {
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 / */
206 /* checking mountpoint crossing is very different when stepping up */
207 host_err
= nfsd_lookup_parent(rqstp
, dparent
, &exp
, &dentry
);
213 * In the nfsd4_open() case, this may be held across
214 * subsequent open and delegation acquisition which may
215 * need to take the child's i_mutex:
217 fh_lock_nested(fhp
, I_MUTEX_PARENT
);
218 dentry
= lookup_one_len(name
, dparent
, len
);
219 host_err
= PTR_ERR(dentry
);
222 if (nfsd_mountpoint(dentry
, exp
)) {
224 * We don't need the i_mutex after all. It's
225 * still possible we could open this (regular
226 * files can be mountpoints too), but the
227 * i_mutex is just there to prevent renames of
228 * something that we might be about to delegate,
229 * and a mountpoint won't be renamed:
232 if ((host_err
= nfsd_cross_mnt(rqstp
, &dentry
, &exp
))) {
238 *dentry_ret
= dentry
;
244 return nfserrno(host_err
);
248 * Look up one component of a pathname.
249 * N.B. After this call _both_ fhp and resfh need an fh_put
251 * If the lookup would cross a mountpoint, and the mounted filesystem
252 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
253 * accepted as it stands and the mounted directory is
254 * returned. Otherwise the covered directory is returned.
255 * NOTE: this mountpoint crossing is not supported properly by all
256 * clients and is explicitly disallowed for NFSv3
257 * NeilBrown <neilb@cse.unsw.edu.au>
260 nfsd_lookup(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, const char *name
,
261 unsigned int len
, struct svc_fh
*resfh
)
263 struct svc_export
*exp
;
264 struct dentry
*dentry
;
267 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_EXEC
);
270 err
= nfsd_lookup_dentry(rqstp
, fhp
, name
, len
, &exp
, &dentry
);
273 err
= check_nfsd_access(exp
, rqstp
);
277 * Note: we compose the file handle now, but as the
278 * dentry may be negative, it may need to be updated.
280 err
= fh_compose(resfh
, exp
, dentry
, fhp
);
281 if (!err
&& d_really_is_negative(dentry
))
290 * Commit metadata changes to stable storage.
293 commit_metadata(struct svc_fh
*fhp
)
295 struct inode
*inode
= d_inode(fhp
->fh_dentry
);
296 const struct export_operations
*export_ops
= inode
->i_sb
->s_export_op
;
298 if (!EX_ISSYNC(fhp
->fh_export
))
301 if (export_ops
->commit_metadata
)
302 return export_ops
->commit_metadata(inode
);
303 return sync_inode_metadata(inode
, 1);
307 * Go over the attributes and take care of the small differences between
308 * NFS semantics and what Linux expects.
311 nfsd_sanitize_attrs(struct inode
*inode
, struct iattr
*iap
)
313 /* sanitize the mode change */
314 if (iap
->ia_valid
& ATTR_MODE
) {
315 iap
->ia_mode
&= S_IALLUGO
;
316 iap
->ia_mode
|= (inode
->i_mode
& ~S_IALLUGO
);
319 /* Revoke setuid/setgid on chown */
320 if (!S_ISDIR(inode
->i_mode
) &&
321 ((iap
->ia_valid
& ATTR_UID
) || (iap
->ia_valid
& ATTR_GID
))) {
322 iap
->ia_valid
|= ATTR_KILL_PRIV
;
323 if (iap
->ia_valid
& ATTR_MODE
) {
324 /* we're setting mode too, just clear the s*id bits */
325 iap
->ia_mode
&= ~S_ISUID
;
326 if (iap
->ia_mode
& S_IXGRP
)
327 iap
->ia_mode
&= ~S_ISGID
;
329 /* set ATTR_KILL_* bits and let VFS handle it */
330 iap
->ia_valid
|= (ATTR_KILL_SUID
| ATTR_KILL_SGID
);
336 nfsd_get_write_access(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
339 struct inode
*inode
= d_inode(fhp
->fh_dentry
);
342 if (iap
->ia_size
< inode
->i_size
) {
345 err
= nfsd_permission(rqstp
, fhp
->fh_export
, fhp
->fh_dentry
,
346 NFSD_MAY_TRUNC
| NFSD_MAY_OWNER_OVERRIDE
);
351 host_err
= get_write_access(inode
);
355 host_err
= locks_verify_truncate(inode
, NULL
, iap
->ia_size
);
357 goto out_put_write_access
;
360 out_put_write_access
:
361 put_write_access(inode
);
363 return nfserrno(host_err
);
367 * Set various file attributes. After this call fhp needs an fh_put.
370 nfsd_setattr(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, struct iattr
*iap
,
371 int check_guard
, time_t guardtime
)
373 struct dentry
*dentry
;
375 int accmode
= NFSD_MAY_SATTR
;
379 bool get_write_count
;
380 bool size_change
= (iap
->ia_valid
& ATTR_SIZE
);
382 if (iap
->ia_valid
& (ATTR_ATIME
| ATTR_MTIME
| ATTR_SIZE
))
383 accmode
|= NFSD_MAY_WRITE
|NFSD_MAY_OWNER_OVERRIDE
;
384 if (iap
->ia_valid
& ATTR_SIZE
)
387 /* Callers that do fh_verify should do the fh_want_write: */
388 get_write_count
= !fhp
->fh_dentry
;
391 err
= fh_verify(rqstp
, fhp
, ftype
, accmode
);
394 if (get_write_count
) {
395 host_err
= fh_want_write(fhp
);
400 dentry
= fhp
->fh_dentry
;
401 inode
= d_inode(dentry
);
403 /* Ignore any mode updates on symlinks */
404 if (S_ISLNK(inode
->i_mode
))
405 iap
->ia_valid
&= ~ATTR_MODE
;
410 nfsd_sanitize_attrs(inode
, iap
);
412 if (check_guard
&& guardtime
!= inode
->i_ctime
.tv_sec
)
413 return nfserr_notsync
;
416 * The size case is special, it changes the file in addition to the
417 * attributes, and file systems don't expect it to be mixed with
418 * "random" attribute changes. We thus split out the size change
419 * into a separate call to ->setattr, and do the rest as a separate
423 err
= nfsd_get_write_access(rqstp
, fhp
, iap
);
431 * RFC5661, Section 18.30.4:
432 * Changing the size of a file with SETATTR indirectly
433 * changes the time_modify and change attributes.
435 * (and similar for the older RFCs)
437 struct iattr size_attr
= {
438 .ia_valid
= ATTR_SIZE
| ATTR_CTIME
| ATTR_MTIME
,
439 .ia_size
= iap
->ia_size
,
442 host_err
= notify_change(dentry
, &size_attr
, NULL
);
445 iap
->ia_valid
&= ~ATTR_SIZE
;
448 * Avoid the additional setattr call below if the only other
449 * attribute that the client sends is the mtime, as we update
450 * it as part of the size change above.
452 if ((iap
->ia_valid
& ~ATTR_MTIME
) == 0)
456 iap
->ia_valid
|= ATTR_CTIME
;
457 host_err
= notify_change(dentry
, iap
, NULL
);
462 put_write_access(inode
);
465 host_err
= commit_metadata(fhp
);
466 return nfserrno(host_err
);
469 #if defined(CONFIG_NFSD_V4)
471 * NFS junction information is stored in an extended attribute.
473 #define NFSD_JUNCTION_XATTR_NAME XATTR_TRUSTED_PREFIX "junction.nfs"
476 * nfsd4_is_junction - Test if an object could be an NFS junction
478 * @dentry: object to test
480 * Returns 1 if "dentry" appears to contain NFS junction information.
481 * Otherwise 0 is returned.
483 int nfsd4_is_junction(struct dentry
*dentry
)
485 struct inode
*inode
= d_inode(dentry
);
489 if (inode
->i_mode
& S_IXUGO
)
491 if (!(inode
->i_mode
& S_ISVTX
))
493 if (vfs_getxattr(dentry
, NFSD_JUNCTION_XATTR_NAME
, NULL
, 0) <= 0)
497 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
498 __be32
nfsd4_set_nfs4_label(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
499 struct xdr_netobj
*label
)
503 struct dentry
*dentry
;
505 error
= fh_verify(rqstp
, fhp
, 0 /* S_IFREG */, NFSD_MAY_SATTR
);
509 dentry
= fhp
->fh_dentry
;
511 inode_lock(d_inode(dentry
));
512 host_error
= security_inode_setsecctx(dentry
, label
->data
, label
->len
);
513 inode_unlock(d_inode(dentry
));
514 return nfserrno(host_error
);
517 __be32
nfsd4_set_nfs4_label(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
518 struct xdr_netobj
*label
)
520 return nfserr_notsupp
;
524 __be32
nfsd4_clone_file_range(struct file
*src
, u64 src_pos
, struct file
*dst
,
525 u64 dst_pos
, u64 count
)
527 return nfserrno(do_clone_file_range(src
, src_pos
, dst
, dst_pos
, count
));
530 ssize_t
nfsd_copy_file_range(struct file
*src
, u64 src_pos
, struct file
*dst
,
531 u64 dst_pos
, u64 count
)
535 * Limit copy to 4MB to prevent indefinitely blocking an nfsd
536 * thread and client rpc slot. The choice of 4MB is somewhat
537 * arbitrary. We might instead base this on r/wsize, or make it
538 * tunable, or use a time instead of a byte limit, or implement
539 * asynchronous copy. In theory a client could also recognize a
540 * limit like this and pipeline multiple COPY requests.
542 count
= min_t(u64
, count
, 1 << 22);
543 return vfs_copy_file_range(src
, src_pos
, dst
, dst_pos
, count
, 0);
546 __be32
nfsd4_vfs_fallocate(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
547 struct file
*file
, loff_t offset
, loff_t len
,
552 if (!S_ISREG(file_inode(file
)->i_mode
))
555 error
= vfs_fallocate(file
, flags
, offset
, len
);
557 error
= commit_metadata(fhp
);
559 return nfserrno(error
);
561 #endif /* defined(CONFIG_NFSD_V4) */
563 #ifdef CONFIG_NFSD_V3
565 * Check server access rights to a file system object
571 static struct accessmap nfs3_regaccess
[] = {
572 { NFS3_ACCESS_READ
, NFSD_MAY_READ
},
573 { NFS3_ACCESS_EXECUTE
, NFSD_MAY_EXEC
},
574 { NFS3_ACCESS_MODIFY
, NFSD_MAY_WRITE
|NFSD_MAY_TRUNC
},
575 { NFS3_ACCESS_EXTEND
, NFSD_MAY_WRITE
},
580 static struct accessmap nfs3_diraccess
[] = {
581 { NFS3_ACCESS_READ
, NFSD_MAY_READ
},
582 { NFS3_ACCESS_LOOKUP
, NFSD_MAY_EXEC
},
583 { NFS3_ACCESS_MODIFY
, NFSD_MAY_EXEC
|NFSD_MAY_WRITE
|NFSD_MAY_TRUNC
},
584 { NFS3_ACCESS_EXTEND
, NFSD_MAY_EXEC
|NFSD_MAY_WRITE
},
585 { NFS3_ACCESS_DELETE
, NFSD_MAY_REMOVE
},
590 static struct accessmap nfs3_anyaccess
[] = {
591 /* Some clients - Solaris 2.6 at least, make an access call
592 * to the server to check for access for things like /dev/null
593 * (which really, the server doesn't care about). So
594 * We provide simple access checking for them, looking
595 * mainly at mode bits, and we make sure to ignore read-only
598 { NFS3_ACCESS_READ
, NFSD_MAY_READ
},
599 { NFS3_ACCESS_EXECUTE
, NFSD_MAY_EXEC
},
600 { NFS3_ACCESS_MODIFY
, NFSD_MAY_WRITE
|NFSD_MAY_LOCAL_ACCESS
},
601 { NFS3_ACCESS_EXTEND
, NFSD_MAY_WRITE
|NFSD_MAY_LOCAL_ACCESS
},
607 nfsd_access(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, u32
*access
, u32
*supported
)
609 struct accessmap
*map
;
610 struct svc_export
*export
;
611 struct dentry
*dentry
;
612 u32 query
, result
= 0, sresult
= 0;
615 error
= fh_verify(rqstp
, fhp
, 0, NFSD_MAY_NOP
);
619 export
= fhp
->fh_export
;
620 dentry
= fhp
->fh_dentry
;
622 if (d_is_reg(dentry
))
623 map
= nfs3_regaccess
;
624 else if (d_is_dir(dentry
))
625 map
= nfs3_diraccess
;
627 map
= nfs3_anyaccess
;
631 for (; map
->access
; map
++) {
632 if (map
->access
& query
) {
635 sresult
|= map
->access
;
637 err2
= nfsd_permission(rqstp
, export
, dentry
, map
->how
);
640 result
|= map
->access
;
643 /* the following error codes just mean the access was not allowed,
644 * rather than an error occurred */
648 /* simply don't "or" in the access bit. */
658 *supported
= sresult
;
663 #endif /* CONFIG_NFSD_V3 */
665 static int nfsd_open_break_lease(struct inode
*inode
, int access
)
669 if (access
& NFSD_MAY_NOT_BREAK_LEASE
)
671 mode
= (access
& NFSD_MAY_WRITE
) ? O_WRONLY
: O_RDONLY
;
672 return break_lease(inode
, mode
| O_NONBLOCK
);
676 * Open an existing file or directory.
677 * The may_flags argument indicates the type of open (read/write/lock)
678 * and additional flags.
679 * N.B. After this call fhp needs an fh_put
682 nfsd_open(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, umode_t type
,
683 int may_flags
, struct file
**filp
)
688 int flags
= O_RDONLY
|O_LARGEFILE
;
692 validate_process_creds();
695 * If we get here, then the client has already done an "open",
696 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
697 * in case a chmod has now revoked permission.
699 * Arguably we should also allow the owner override for
700 * directories, but we never have and it doesn't seem to have
701 * caused anyone a problem. If we were to change this, note
702 * also that our filldir callbacks would need a variant of
703 * lookup_one_len that doesn't check permissions.
706 may_flags
|= NFSD_MAY_OWNER_OVERRIDE
;
707 err
= fh_verify(rqstp
, fhp
, type
, may_flags
);
711 path
.mnt
= fhp
->fh_export
->ex_path
.mnt
;
712 path
.dentry
= fhp
->fh_dentry
;
713 inode
= d_inode(path
.dentry
);
715 /* Disallow write access to files with the append-only bit set
716 * or any access when mandatory locking enabled
719 if (IS_APPEND(inode
) && (may_flags
& NFSD_MAY_WRITE
))
722 * We must ignore files (but only files) which might have mandatory
723 * locks on them because there is no way to know if the accesser has
726 if (S_ISREG((inode
)->i_mode
) && mandatory_lock(inode
))
732 host_err
= nfsd_open_break_lease(inode
, may_flags
);
733 if (host_err
) /* NOMEM or WOULDBLOCK */
736 if (may_flags
& NFSD_MAY_WRITE
) {
737 if (may_flags
& NFSD_MAY_READ
)
738 flags
= O_RDWR
|O_LARGEFILE
;
740 flags
= O_WRONLY
|O_LARGEFILE
;
743 file
= dentry_open(&path
, flags
, current_cred());
745 host_err
= PTR_ERR(file
);
749 host_err
= ima_file_check(file
, may_flags
, 0);
755 if (may_flags
& NFSD_MAY_64BIT_COOKIE
)
756 file
->f_mode
|= FMODE_64BITHASH
;
758 file
->f_mode
|= FMODE_32BITHASH
;
762 err
= nfserrno(host_err
);
764 validate_process_creds();
769 nfsd_init_raparms(struct file
*file
)
771 struct inode
*inode
= file_inode(file
);
772 dev_t dev
= inode
->i_sb
->s_dev
;
773 ino_t ino
= inode
->i_ino
;
774 struct raparms
*ra
, **rap
, **frap
= NULL
;
777 struct raparm_hbucket
*rab
;
779 hash
= jhash_2words(dev
, ino
, 0xfeedbeef) & RAPARM_HASH_MASK
;
780 rab
= &raparm_hash
[hash
];
782 spin_lock(&rab
->pb_lock
);
783 for (rap
= &rab
->pb_head
; (ra
= *rap
); rap
= &ra
->p_next
) {
784 if (ra
->p_ino
== ino
&& ra
->p_dev
== dev
)
787 if (ra
->p_count
== 0)
790 depth
= nfsdstats
.ra_size
;
792 spin_unlock(&rab
->pb_lock
);
802 if (rap
!= &rab
->pb_head
) {
804 ra
->p_next
= rab
->pb_head
;
808 nfsdstats
.ra_depth
[depth
*10/nfsdstats
.ra_size
]++;
809 spin_unlock(&rab
->pb_lock
);
812 file
->f_ra
= ra
->p_ra
;
816 void nfsd_put_raparams(struct file
*file
, struct raparms
*ra
)
818 struct raparm_hbucket
*rab
= &raparm_hash
[ra
->p_hindex
];
820 spin_lock(&rab
->pb_lock
);
821 ra
->p_ra
= file
->f_ra
;
824 spin_unlock(&rab
->pb_lock
);
828 * Grab and keep cached pages associated with a file in the svc_rqst
829 * so that they can be passed to the network sendmsg/sendpage routines
830 * directly. They will be released after the sending has completed.
833 nfsd_splice_actor(struct pipe_inode_info
*pipe
, struct pipe_buffer
*buf
,
834 struct splice_desc
*sd
)
836 struct svc_rqst
*rqstp
= sd
->u
.data
;
837 struct page
**pp
= rqstp
->rq_next_page
;
838 struct page
*page
= buf
->page
;
843 if (rqstp
->rq_res
.page_len
== 0) {
845 put_page(*rqstp
->rq_next_page
);
846 *(rqstp
->rq_next_page
++) = page
;
847 rqstp
->rq_res
.page_base
= buf
->offset
;
848 rqstp
->rq_res
.page_len
= size
;
849 } else if (page
!= pp
[-1]) {
851 if (*rqstp
->rq_next_page
)
852 put_page(*rqstp
->rq_next_page
);
853 *(rqstp
->rq_next_page
++) = page
;
854 rqstp
->rq_res
.page_len
+= size
;
856 rqstp
->rq_res
.page_len
+= size
;
861 static int nfsd_direct_splice_actor(struct pipe_inode_info
*pipe
,
862 struct splice_desc
*sd
)
864 return __splice_from_pipe(pipe
, sd
, nfsd_splice_actor
);
868 nfsd_finish_read(struct file
*file
, unsigned long *count
, int host_err
)
871 nfsdstats
.io_read
+= host_err
;
873 fsnotify_access(file
);
876 return nfserrno(host_err
);
879 __be32
nfsd_splice_read(struct svc_rqst
*rqstp
,
880 struct file
*file
, loff_t offset
, unsigned long *count
)
882 struct splice_desc sd
= {
890 rqstp
->rq_next_page
= rqstp
->rq_respages
+ 1;
891 host_err
= splice_direct_to_actor(file
, &sd
, nfsd_direct_splice_actor
);
892 return nfsd_finish_read(file
, count
, host_err
);
895 __be32
nfsd_readv(struct file
*file
, loff_t offset
, struct kvec
*vec
, int vlen
,
896 unsigned long *count
)
903 host_err
= vfs_readv(file
, (struct iovec __user
*)vec
, vlen
, &offset
, 0);
905 return nfsd_finish_read(file
, count
, host_err
);
909 nfsd_vfs_read(struct svc_rqst
*rqstp
, struct file
*file
,
910 loff_t offset
, struct kvec
*vec
, int vlen
, unsigned long *count
)
912 if (file
->f_op
->splice_read
&& test_bit(RQ_SPLICE_OK
, &rqstp
->rq_flags
))
913 return nfsd_splice_read(rqstp
, file
, offset
, count
);
915 return nfsd_readv(file
, offset
, vec
, vlen
, count
);
919 * Gathered writes: If another process is currently writing to the file,
920 * there's a high chance this is another nfsd (triggered by a bulk write
921 * from a client's biod). Rather than syncing the file with each write
922 * request, we sleep for 10 msec.
924 * I don't know if this roughly approximates C. Juszak's idea of
925 * gathered writes, but it's a nice and simple solution (IMHO), and it
928 * Note: we do this only in the NFSv2 case, since v3 and higher have a
929 * better tool (separate unstable writes and commits) for solving this
932 static int wait_for_concurrent_writes(struct file
*file
)
934 struct inode
*inode
= file_inode(file
);
935 static ino_t last_ino
;
936 static dev_t last_dev
;
939 if (atomic_read(&inode
->i_writecount
) > 1
940 || (last_ino
== inode
->i_ino
&& last_dev
== inode
->i_sb
->s_dev
)) {
941 dprintk("nfsd: write defer %d\n", task_pid_nr(current
));
943 dprintk("nfsd: write resume %d\n", task_pid_nr(current
));
946 if (inode
->i_state
& I_DIRTY
) {
947 dprintk("nfsd: write sync %d\n", task_pid_nr(current
));
948 err
= vfs_fsync(file
, 0);
950 last_ino
= inode
->i_ino
;
951 last_dev
= inode
->i_sb
->s_dev
;
956 nfsd_vfs_write(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, struct file
*file
,
957 loff_t offset
, struct kvec
*vec
, int vlen
,
958 unsigned long *cnt
, int *stablep
)
960 struct svc_export
*exp
;
965 int stable
= *stablep
;
968 unsigned int pflags
= current
->flags
;
971 if (test_bit(RQ_LOCAL
, &rqstp
->rq_flags
))
973 * We want less throttling in balance_dirty_pages()
974 * and shrink_inactive_list() so that nfs to
975 * localhost doesn't cause nfsd to lock up due to all
976 * the client's dirty pages or its congested queue.
978 current
->flags
|= PF_LESS_THROTTLE
;
980 inode
= file_inode(file
);
981 exp
= fhp
->fh_export
;
983 use_wgather
= (rqstp
->rq_vers
== 2) && EX_WGATHER(exp
);
988 if (stable
&& !use_wgather
)
991 /* Write the data. */
992 oldfs
= get_fs(); set_fs(KERNEL_DS
);
993 host_err
= vfs_writev(file
, (struct iovec __user
*)vec
, vlen
, &pos
, flags
);
998 nfsdstats
.io_write
+= host_err
;
999 fsnotify_modify(file
);
1001 if (stable
&& use_wgather
)
1002 host_err
= wait_for_concurrent_writes(file
);
1005 dprintk("nfsd: write complete host_err=%d\n", host_err
);
1009 err
= nfserrno(host_err
);
1010 if (test_bit(RQ_LOCAL
, &rqstp
->rq_flags
))
1011 tsk_restore_flags(current
, pflags
, PF_LESS_THROTTLE
);
1016 * Read data from a file. count must contain the requested read count
1017 * on entry. On return, *count contains the number of bytes actually read.
1018 * N.B. After this call fhp needs an fh_put
1020 __be32
nfsd_read(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1021 loff_t offset
, struct kvec
*vec
, int vlen
, unsigned long *count
)
1027 trace_read_start(rqstp
, fhp
, offset
, vlen
);
1028 err
= nfsd_open(rqstp
, fhp
, S_IFREG
, NFSD_MAY_READ
, &file
);
1032 ra
= nfsd_init_raparms(file
);
1034 trace_read_opened(rqstp
, fhp
, offset
, vlen
);
1035 err
= nfsd_vfs_read(rqstp
, file
, offset
, vec
, vlen
, count
);
1036 trace_read_io_done(rqstp
, fhp
, offset
, vlen
);
1039 nfsd_put_raparams(file
, ra
);
1042 trace_read_done(rqstp
, fhp
, offset
, vlen
);
1048 * Write data to a file.
1049 * The stable flag requests synchronous writes.
1050 * N.B. After this call fhp needs an fh_put
1053 nfsd_write(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, struct file
*file
,
1054 loff_t offset
, struct kvec
*vec
, int vlen
, unsigned long *cnt
,
1059 trace_write_start(rqstp
, fhp
, offset
, vlen
);
1062 err
= nfsd_permission(rqstp
, fhp
->fh_export
, fhp
->fh_dentry
,
1063 NFSD_MAY_WRITE
|NFSD_MAY_OWNER_OVERRIDE
);
1066 trace_write_opened(rqstp
, fhp
, offset
, vlen
);
1067 err
= nfsd_vfs_write(rqstp
, fhp
, file
, offset
, vec
, vlen
, cnt
,
1069 trace_write_io_done(rqstp
, fhp
, offset
, vlen
);
1071 err
= nfsd_open(rqstp
, fhp
, S_IFREG
, NFSD_MAY_WRITE
, &file
);
1075 trace_write_opened(rqstp
, fhp
, offset
, vlen
);
1077 err
= nfsd_vfs_write(rqstp
, fhp
, file
, offset
, vec
, vlen
,
1079 trace_write_io_done(rqstp
, fhp
, offset
, vlen
);
1083 trace_write_done(rqstp
, fhp
, offset
, vlen
);
1087 #ifdef CONFIG_NFSD_V3
1089 * Commit all pending writes to stable storage.
1091 * Note: we only guarantee that data that lies within the range specified
1092 * by the 'offset' and 'count' parameters will be synced.
1094 * Unfortunately we cannot lock the file to make sure we return full WCC
1095 * data to the client, as locking happens lower down in the filesystem.
1098 nfsd_commit(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1099 loff_t offset
, unsigned long count
)
1102 loff_t end
= LLONG_MAX
;
1103 __be32 err
= nfserr_inval
;
1108 end
= offset
+ (loff_t
)count
- 1;
1113 err
= nfsd_open(rqstp
, fhp
, S_IFREG
,
1114 NFSD_MAY_WRITE
|NFSD_MAY_NOT_BREAK_LEASE
, &file
);
1117 if (EX_ISSYNC(fhp
->fh_export
)) {
1118 int err2
= vfs_fsync_range(file
, offset
, end
, 0);
1120 if (err2
!= -EINVAL
)
1121 err
= nfserrno(err2
);
1123 err
= nfserr_notsupp
;
1130 #endif /* CONFIG_NFSD_V3 */
1133 nfsd_create_setattr(struct svc_rqst
*rqstp
, struct svc_fh
*resfhp
,
1137 * Mode has already been set earlier in create:
1139 iap
->ia_valid
&= ~ATTR_MODE
;
1141 * Setting uid/gid works only for root. Irix appears to
1142 * send along the gid on create when it tries to implement
1143 * setgid directories via NFS:
1145 if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID
))
1146 iap
->ia_valid
&= ~(ATTR_UID
|ATTR_GID
);
1148 return nfsd_setattr(rqstp
, resfhp
, iap
, 0, (time_t)0);
1149 /* Callers expect file metadata to be committed here */
1150 return nfserrno(commit_metadata(resfhp
));
1153 /* HPUX client sometimes creates a file in mode 000, and sets size to 0.
1154 * setting size to 0 may fail for some specific file systems by the permission
1155 * checking which requires WRITE permission but the mode is 000.
1156 * we ignore the resizing(to 0) on the just new created file, since the size is
1157 * 0 after file created.
1159 * call this only after vfs_create() is called.
1162 nfsd_check_ignore_resizing(struct iattr
*iap
)
1164 if ((iap
->ia_valid
& ATTR_SIZE
) && (iap
->ia_size
== 0))
1165 iap
->ia_valid
&= ~ATTR_SIZE
;
1168 /* The parent directory should already be locked: */
1170 nfsd_create_locked(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1171 char *fname
, int flen
, struct iattr
*iap
,
1172 int type
, dev_t rdev
, struct svc_fh
*resfhp
)
1174 struct dentry
*dentry
, *dchild
;
1180 dentry
= fhp
->fh_dentry
;
1181 dirp
= d_inode(dentry
);
1183 dchild
= dget(resfhp
->fh_dentry
);
1184 if (!fhp
->fh_locked
) {
1185 WARN_ONCE(1, "nfsd_create: parent %pd2 not locked!\n",
1191 err
= nfsd_permission(rqstp
, fhp
->fh_export
, dentry
, NFSD_MAY_CREATE
);
1195 if (!(iap
->ia_valid
& ATTR_MODE
))
1197 iap
->ia_mode
= (iap
->ia_mode
& S_IALLUGO
) | type
;
1203 host_err
= vfs_create(dirp
, dchild
, iap
->ia_mode
, true);
1205 nfsd_check_ignore_resizing(iap
);
1208 host_err
= vfs_mkdir(dirp
, dchild
, iap
->ia_mode
);
1214 host_err
= vfs_mknod(dirp
, dchild
, iap
->ia_mode
, rdev
);
1217 printk(KERN_WARNING
"nfsd: bad file type %o in nfsd_create\n",
1224 err
= nfsd_create_setattr(rqstp
, resfhp
, iap
);
1227 * nfsd_create_setattr already committed the child. Transactional
1228 * filesystems had a chance to commit changes for both parent and
1229 * child simultaneously making the following commit_metadata a
1232 err2
= nfserrno(commit_metadata(fhp
));
1236 * Update the file handle to get the new inode info.
1239 err
= fh_update(resfhp
);
1245 err
= nfserrno(host_err
);
1250 * Create a filesystem object (regular, directory, special).
1251 * Note that the parent directory is left locked.
1253 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1256 nfsd_create(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1257 char *fname
, int flen
, struct iattr
*iap
,
1258 int type
, dev_t rdev
, struct svc_fh
*resfhp
)
1260 struct dentry
*dentry
, *dchild
= NULL
;
1265 if (isdotent(fname
, flen
))
1266 return nfserr_exist
;
1268 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_NOP
);
1272 dentry
= fhp
->fh_dentry
;
1273 dirp
= d_inode(dentry
);
1275 host_err
= fh_want_write(fhp
);
1277 return nfserrno(host_err
);
1279 fh_lock_nested(fhp
, I_MUTEX_PARENT
);
1280 dchild
= lookup_one_len(fname
, dentry
, flen
);
1281 host_err
= PTR_ERR(dchild
);
1283 return nfserrno(host_err
);
1284 err
= fh_compose(resfhp
, fhp
->fh_export
, dchild
, fhp
);
1286 * We unconditionally drop our ref to dchild as fh_compose will have
1287 * already grabbed its own ref for it.
1292 return nfsd_create_locked(rqstp
, fhp
, fname
, flen
, iap
, type
,
1296 #ifdef CONFIG_NFSD_V3
1299 * NFSv3 and NFSv4 version of nfsd_create
1302 do_nfsd_create(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1303 char *fname
, int flen
, struct iattr
*iap
,
1304 struct svc_fh
*resfhp
, int createmode
, u32
*verifier
,
1305 bool *truncp
, bool *created
)
1307 struct dentry
*dentry
, *dchild
= NULL
;
1311 __u32 v_mtime
=0, v_atime
=0;
1317 if (isdotent(fname
, flen
))
1319 if (!(iap
->ia_valid
& ATTR_MODE
))
1321 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_EXEC
);
1325 dentry
= fhp
->fh_dentry
;
1326 dirp
= d_inode(dentry
);
1328 host_err
= fh_want_write(fhp
);
1332 fh_lock_nested(fhp
, I_MUTEX_PARENT
);
1335 * Compose the response file handle.
1337 dchild
= lookup_one_len(fname
, dentry
, flen
);
1338 host_err
= PTR_ERR(dchild
);
1342 /* If file doesn't exist, check for permissions to create one */
1343 if (d_really_is_negative(dchild
)) {
1344 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_CREATE
);
1349 err
= fh_compose(resfhp
, fhp
->fh_export
, dchild
, fhp
);
1353 if (nfsd_create_is_exclusive(createmode
)) {
1354 /* solaris7 gets confused (bugid 4218508) if these have
1355 * the high bit set, so just clear the high bits. If this is
1356 * ever changed to use different attrs for storing the
1357 * verifier, then do_open_lookup() will also need to be fixed
1360 v_mtime
= verifier
[0]&0x7fffffff;
1361 v_atime
= verifier
[1]&0x7fffffff;
1364 if (d_really_is_positive(dchild
)) {
1367 switch (createmode
) {
1368 case NFS3_CREATE_UNCHECKED
:
1369 if (! d_is_reg(dchild
))
1372 /* in nfsv4, we need to treat this case a little
1373 * differently. we don't want to truncate the
1374 * file now; this would be wrong if the OPEN
1375 * fails for some other reason. furthermore,
1376 * if the size is nonzero, we should ignore it
1377 * according to spec!
1379 *truncp
= (iap
->ia_valid
& ATTR_SIZE
) && !iap
->ia_size
;
1382 iap
->ia_valid
&= ATTR_SIZE
;
1386 case NFS3_CREATE_EXCLUSIVE
:
1387 if ( d_inode(dchild
)->i_mtime
.tv_sec
== v_mtime
1388 && d_inode(dchild
)->i_atime
.tv_sec
== v_atime
1389 && d_inode(dchild
)->i_size
== 0 ) {
1394 case NFS4_CREATE_EXCLUSIVE4_1
:
1395 if ( d_inode(dchild
)->i_mtime
.tv_sec
== v_mtime
1396 && d_inode(dchild
)->i_atime
.tv_sec
== v_atime
1397 && d_inode(dchild
)->i_size
== 0 ) {
1403 case NFS3_CREATE_GUARDED
:
1410 host_err
= vfs_create(dirp
, dchild
, iap
->ia_mode
, true);
1418 nfsd_check_ignore_resizing(iap
);
1420 if (nfsd_create_is_exclusive(createmode
)) {
1421 /* Cram the verifier into atime/mtime */
1422 iap
->ia_valid
= ATTR_MTIME
|ATTR_ATIME
1423 | ATTR_MTIME_SET
|ATTR_ATIME_SET
;
1424 /* XXX someone who knows this better please fix it for nsec */
1425 iap
->ia_mtime
.tv_sec
= v_mtime
;
1426 iap
->ia_atime
.tv_sec
= v_atime
;
1427 iap
->ia_mtime
.tv_nsec
= 0;
1428 iap
->ia_atime
.tv_nsec
= 0;
1432 err
= nfsd_create_setattr(rqstp
, resfhp
, iap
);
1435 * nfsd_create_setattr already committed the child
1436 * (and possibly also the parent).
1439 err
= nfserrno(commit_metadata(fhp
));
1442 * Update the filehandle to get the new inode info.
1445 err
= fh_update(resfhp
);
1449 if (dchild
&& !IS_ERR(dchild
))
1455 err
= nfserrno(host_err
);
1458 #endif /* CONFIG_NFSD_V3 */
1461 * Read a symlink. On entry, *lenp must contain the maximum path length that
1462 * fits into the buffer. On return, it contains the true length.
1463 * N.B. After this call fhp needs an fh_put
1466 nfsd_readlink(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, char *buf
, int *lenp
)
1473 err
= fh_verify(rqstp
, fhp
, S_IFLNK
, NFSD_MAY_NOP
);
1477 path
.mnt
= fhp
->fh_export
->ex_path
.mnt
;
1478 path
.dentry
= fhp
->fh_dentry
;
1481 if (!d_is_symlink(path
.dentry
))
1485 /* N.B. Why does this call need a get_fs()??
1486 * Remove the set_fs and watch the fireworks:-) --okir
1489 oldfs
= get_fs(); set_fs(KERNEL_DS
);
1490 host_err
= vfs_readlink(path
.dentry
, (char __user
*)buf
, *lenp
);
1501 err
= nfserrno(host_err
);
1506 * Create a symlink and look up its inode
1507 * N.B. After this call _both_ fhp and resfhp need an fh_put
1510 nfsd_symlink(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
,
1511 char *fname
, int flen
,
1513 struct svc_fh
*resfhp
)
1515 struct dentry
*dentry
, *dnew
;
1520 if (!flen
|| path
[0] == '\0')
1523 if (isdotent(fname
, flen
))
1526 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_CREATE
);
1530 host_err
= fh_want_write(fhp
);
1535 dentry
= fhp
->fh_dentry
;
1536 dnew
= lookup_one_len(fname
, dentry
, flen
);
1537 host_err
= PTR_ERR(dnew
);
1541 host_err
= vfs_symlink(d_inode(dentry
), dnew
, path
);
1542 err
= nfserrno(host_err
);
1544 err
= nfserrno(commit_metadata(fhp
));
1549 cerr
= fh_compose(resfhp
, fhp
->fh_export
, dnew
, fhp
);
1551 if (err
==0) err
= cerr
;
1556 err
= nfserrno(host_err
);
1562 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1565 nfsd_link(struct svc_rqst
*rqstp
, struct svc_fh
*ffhp
,
1566 char *name
, int len
, struct svc_fh
*tfhp
)
1568 struct dentry
*ddir
, *dnew
, *dold
;
1573 err
= fh_verify(rqstp
, ffhp
, S_IFDIR
, NFSD_MAY_CREATE
);
1576 err
= fh_verify(rqstp
, tfhp
, 0, NFSD_MAY_NOP
);
1580 if (d_is_dir(tfhp
->fh_dentry
))
1586 if (isdotent(name
, len
))
1589 host_err
= fh_want_write(tfhp
);
1591 err
= nfserrno(host_err
);
1595 fh_lock_nested(ffhp
, I_MUTEX_PARENT
);
1596 ddir
= ffhp
->fh_dentry
;
1597 dirp
= d_inode(ddir
);
1599 dnew
= lookup_one_len(name
, ddir
, len
);
1600 host_err
= PTR_ERR(dnew
);
1604 dold
= tfhp
->fh_dentry
;
1607 if (d_really_is_negative(dold
))
1609 host_err
= vfs_link(dold
, dirp
, dnew
, NULL
);
1611 err
= nfserrno(commit_metadata(ffhp
));
1613 err
= nfserrno(commit_metadata(tfhp
));
1615 if (host_err
== -EXDEV
&& rqstp
->rq_vers
== 2)
1618 err
= nfserrno(host_err
);
1624 fh_drop_write(tfhp
);
1629 err
= nfserrno(host_err
);
1635 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1638 nfsd_rename(struct svc_rqst
*rqstp
, struct svc_fh
*ffhp
, char *fname
, int flen
,
1639 struct svc_fh
*tfhp
, char *tname
, int tlen
)
1641 struct dentry
*fdentry
, *tdentry
, *odentry
, *ndentry
, *trap
;
1642 struct inode
*fdir
, *tdir
;
1646 err
= fh_verify(rqstp
, ffhp
, S_IFDIR
, NFSD_MAY_REMOVE
);
1649 err
= fh_verify(rqstp
, tfhp
, S_IFDIR
, NFSD_MAY_CREATE
);
1653 fdentry
= ffhp
->fh_dentry
;
1654 fdir
= d_inode(fdentry
);
1656 tdentry
= tfhp
->fh_dentry
;
1657 tdir
= d_inode(tdentry
);
1660 if (!flen
|| isdotent(fname
, flen
) || !tlen
|| isdotent(tname
, tlen
))
1663 host_err
= fh_want_write(ffhp
);
1665 err
= nfserrno(host_err
);
1669 /* cannot use fh_lock as we need deadlock protective ordering
1670 * so do it by hand */
1671 trap
= lock_rename(tdentry
, fdentry
);
1672 ffhp
->fh_locked
= tfhp
->fh_locked
= true;
1676 odentry
= lookup_one_len(fname
, fdentry
, flen
);
1677 host_err
= PTR_ERR(odentry
);
1678 if (IS_ERR(odentry
))
1682 if (d_really_is_negative(odentry
))
1685 if (odentry
== trap
)
1688 ndentry
= lookup_one_len(tname
, tdentry
, tlen
);
1689 host_err
= PTR_ERR(ndentry
);
1690 if (IS_ERR(ndentry
))
1692 host_err
= -ENOTEMPTY
;
1693 if (ndentry
== trap
)
1697 if (ffhp
->fh_export
->ex_path
.mnt
!= tfhp
->fh_export
->ex_path
.mnt
)
1699 if (ffhp
->fh_export
->ex_path
.dentry
!= tfhp
->fh_export
->ex_path
.dentry
)
1702 host_err
= vfs_rename(fdir
, odentry
, tdir
, ndentry
, NULL
, 0);
1704 host_err
= commit_metadata(tfhp
);
1706 host_err
= commit_metadata(ffhp
);
1713 err
= nfserrno(host_err
);
1715 * We cannot rely on fh_unlock on the two filehandles,
1716 * as that would do the wrong thing if the two directories
1717 * were the same, so again we do it by hand.
1719 fill_post_wcc(ffhp
);
1720 fill_post_wcc(tfhp
);
1721 unlock_rename(tdentry
, fdentry
);
1722 ffhp
->fh_locked
= tfhp
->fh_locked
= false;
1723 fh_drop_write(ffhp
);
1730 * Unlink a file or directory
1731 * N.B. After this call fhp needs an fh_put
1734 nfsd_unlink(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, int type
,
1735 char *fname
, int flen
)
1737 struct dentry
*dentry
, *rdentry
;
1743 if (!flen
|| isdotent(fname
, flen
))
1745 err
= fh_verify(rqstp
, fhp
, S_IFDIR
, NFSD_MAY_REMOVE
);
1749 host_err
= fh_want_write(fhp
);
1753 fh_lock_nested(fhp
, I_MUTEX_PARENT
);
1754 dentry
= fhp
->fh_dentry
;
1755 dirp
= d_inode(dentry
);
1757 rdentry
= lookup_one_len(fname
, dentry
, flen
);
1758 host_err
= PTR_ERR(rdentry
);
1759 if (IS_ERR(rdentry
))
1762 if (d_really_is_negative(rdentry
)) {
1769 type
= d_inode(rdentry
)->i_mode
& S_IFMT
;
1771 if (type
!= S_IFDIR
)
1772 host_err
= vfs_unlink(dirp
, rdentry
, NULL
);
1774 host_err
= vfs_rmdir(dirp
, rdentry
);
1776 host_err
= commit_metadata(fhp
);
1780 err
= nfserrno(host_err
);
1786 * We do this buffering because we must not call back into the file
1787 * system's ->lookup() method from the filldir callback. That may well
1788 * deadlock a number of file systems.
1790 * This is based heavily on the implementation of same in XFS.
1792 struct buffered_dirent
{
1796 unsigned int d_type
;
1800 struct readdir_data
{
1801 struct dir_context ctx
;
1807 static int nfsd_buffered_filldir(struct dir_context
*ctx
, const char *name
,
1808 int namlen
, loff_t offset
, u64 ino
,
1809 unsigned int d_type
)
1811 struct readdir_data
*buf
=
1812 container_of(ctx
, struct readdir_data
, ctx
);
1813 struct buffered_dirent
*de
= (void *)(buf
->dirent
+ buf
->used
);
1814 unsigned int reclen
;
1816 reclen
= ALIGN(sizeof(struct buffered_dirent
) + namlen
, sizeof(u64
));
1817 if (buf
->used
+ reclen
> PAGE_SIZE
) {
1822 de
->namlen
= namlen
;
1823 de
->offset
= offset
;
1825 de
->d_type
= d_type
;
1826 memcpy(de
->name
, name
, namlen
);
1827 buf
->used
+= reclen
;
1832 static __be32
nfsd_buffered_readdir(struct file
*file
, nfsd_filldir_t func
,
1833 struct readdir_cd
*cdp
, loff_t
*offsetp
)
1835 struct buffered_dirent
*de
;
1839 struct readdir_data buf
= {
1840 .ctx
.actor
= nfsd_buffered_filldir
,
1841 .dirent
= (void *)__get_free_page(GFP_KERNEL
)
1845 return nfserrno(-ENOMEM
);
1850 unsigned int reclen
;
1852 cdp
->err
= nfserr_eof
; /* will be cleared on successful read */
1856 host_err
= iterate_dir(file
, &buf
.ctx
);
1868 de
= (struct buffered_dirent
*)buf
.dirent
;
1870 offset
= de
->offset
;
1872 if (func(cdp
, de
->name
, de
->namlen
, de
->offset
,
1873 de
->ino
, de
->d_type
))
1876 if (cdp
->err
!= nfs_ok
)
1879 reclen
= ALIGN(sizeof(*de
) + de
->namlen
,
1882 de
= (struct buffered_dirent
*)((char *)de
+ reclen
);
1884 if (size
> 0) /* We bailed out early */
1887 offset
= vfs_llseek(file
, 0, SEEK_CUR
);
1890 free_page((unsigned long)(buf
.dirent
));
1893 return nfserrno(host_err
);
1900 * Read entries from a directory.
1901 * The NFSv3/4 verifier we ignore for now.
1904 nfsd_readdir(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, loff_t
*offsetp
,
1905 struct readdir_cd
*cdp
, nfsd_filldir_t func
)
1909 loff_t offset
= *offsetp
;
1910 int may_flags
= NFSD_MAY_READ
;
1912 /* NFSv2 only supports 32 bit cookies */
1913 if (rqstp
->rq_vers
> 2)
1914 may_flags
|= NFSD_MAY_64BIT_COOKIE
;
1916 err
= nfsd_open(rqstp
, fhp
, S_IFDIR
, may_flags
, &file
);
1920 offset
= vfs_llseek(file
, offset
, SEEK_SET
);
1922 err
= nfserrno((int)offset
);
1926 err
= nfsd_buffered_readdir(file
, func
, cdp
, offsetp
);
1928 if (err
== nfserr_eof
|| err
== nfserr_toosmall
)
1929 err
= nfs_ok
; /* can still be found in ->err */
1937 * Get file system stats
1938 * N.B. After this call fhp needs an fh_put
1941 nfsd_statfs(struct svc_rqst
*rqstp
, struct svc_fh
*fhp
, struct kstatfs
*stat
, int access
)
1945 err
= fh_verify(rqstp
, fhp
, 0, NFSD_MAY_NOP
| access
);
1947 struct path path
= {
1948 .mnt
= fhp
->fh_export
->ex_path
.mnt
,
1949 .dentry
= fhp
->fh_dentry
,
1951 if (vfs_statfs(&path
, stat
))
1957 static int exp_rdonly(struct svc_rqst
*rqstp
, struct svc_export
*exp
)
1959 return nfsexp_flags(rqstp
, exp
) & NFSEXP_READONLY
;
1963 * Check for a user's access permissions to this inode.
1966 nfsd_permission(struct svc_rqst
*rqstp
, struct svc_export
*exp
,
1967 struct dentry
*dentry
, int acc
)
1969 struct inode
*inode
= d_inode(dentry
);
1972 if ((acc
& NFSD_MAY_MASK
) == NFSD_MAY_NOP
)
1975 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
1977 (acc
& NFSD_MAY_READ
)? " read" : "",
1978 (acc
& NFSD_MAY_WRITE
)? " write" : "",
1979 (acc
& NFSD_MAY_EXEC
)? " exec" : "",
1980 (acc
& NFSD_MAY_SATTR
)? " sattr" : "",
1981 (acc
& NFSD_MAY_TRUNC
)? " trunc" : "",
1982 (acc
& NFSD_MAY_LOCK
)? " lock" : "",
1983 (acc
& NFSD_MAY_OWNER_OVERRIDE
)? " owneroverride" : "",
1985 IS_IMMUTABLE(inode
)? " immut" : "",
1986 IS_APPEND(inode
)? " append" : "",
1987 __mnt_is_readonly(exp
->ex_path
.mnt
)? " ro" : "");
1988 dprintk(" owner %d/%d user %d/%d\n",
1989 inode
->i_uid
, inode
->i_gid
, current_fsuid(), current_fsgid());
1992 /* Normally we reject any write/sattr etc access on a read-only file
1993 * system. But if it is IRIX doing check on write-access for a
1994 * device special file, we ignore rofs.
1996 if (!(acc
& NFSD_MAY_LOCAL_ACCESS
))
1997 if (acc
& (NFSD_MAY_WRITE
| NFSD_MAY_SATTR
| NFSD_MAY_TRUNC
)) {
1998 if (exp_rdonly(rqstp
, exp
) ||
1999 __mnt_is_readonly(exp
->ex_path
.mnt
))
2001 if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode
))
2004 if ((acc
& NFSD_MAY_TRUNC
) && IS_APPEND(inode
))
2007 if (acc
& NFSD_MAY_LOCK
) {
2008 /* If we cannot rely on authentication in NLM requests,
2009 * just allow locks, otherwise require read permission, or
2012 if (exp
->ex_flags
& NFSEXP_NOAUTHNLM
)
2015 acc
= NFSD_MAY_READ
| NFSD_MAY_OWNER_OVERRIDE
;
2018 * The file owner always gets access permission for accesses that
2019 * would normally be checked at open time. This is to make
2020 * file access work even when the client has done a fchmod(fd, 0).
2022 * However, `cp foo bar' should fail nevertheless when bar is
2023 * readonly. A sensible way to do this might be to reject all
2024 * attempts to truncate a read-only file, because a creat() call
2025 * always implies file truncation.
2026 * ... but this isn't really fair. A process may reasonably call
2027 * ftruncate on an open file descriptor on a file with perm 000.
2028 * We must trust the client to do permission checking - using "ACCESS"
2031 if ((acc
& NFSD_MAY_OWNER_OVERRIDE
) &&
2032 uid_eq(inode
->i_uid
, current_fsuid()))
2035 /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
2036 err
= inode_permission(inode
, acc
& (MAY_READ
|MAY_WRITE
|MAY_EXEC
));
2038 /* Allow read access to binaries even when mode 111 */
2039 if (err
== -EACCES
&& S_ISREG(inode
->i_mode
) &&
2040 (acc
== (NFSD_MAY_READ
| NFSD_MAY_OWNER_OVERRIDE
) ||
2041 acc
== (NFSD_MAY_READ
| NFSD_MAY_READ_IF_EXEC
)))
2042 err
= inode_permission(inode
, MAY_EXEC
);
2044 return err
? nfserrno(err
) : 0;
2048 nfsd_racache_shutdown(void)
2050 struct raparms
*raparm
, *last_raparm
;
2053 dprintk("nfsd: freeing readahead buffers.\n");
2055 for (i
= 0; i
< RAPARM_HASH_SIZE
; i
++) {
2056 raparm
= raparm_hash
[i
].pb_head
;
2058 last_raparm
= raparm
;
2059 raparm
= raparm
->p_next
;
2062 raparm_hash
[i
].pb_head
= NULL
;
2066 * Initialize readahead param cache
2069 nfsd_racache_init(int cache_size
)
2074 struct raparms
**raparm
= NULL
;
2077 if (raparm_hash
[0].pb_head
)
2079 nperbucket
= DIV_ROUND_UP(cache_size
, RAPARM_HASH_SIZE
);
2080 nperbucket
= max(2, nperbucket
);
2081 cache_size
= nperbucket
* RAPARM_HASH_SIZE
;
2083 dprintk("nfsd: allocating %d readahead buffers.\n", cache_size
);
2085 for (i
= 0; i
< RAPARM_HASH_SIZE
; i
++) {
2086 spin_lock_init(&raparm_hash
[i
].pb_lock
);
2088 raparm
= &raparm_hash
[i
].pb_head
;
2089 for (j
= 0; j
< nperbucket
; j
++) {
2090 *raparm
= kzalloc(sizeof(struct raparms
), GFP_KERNEL
);
2093 raparm
= &(*raparm
)->p_next
;
2098 nfsdstats
.ra_size
= cache_size
;
2102 dprintk("nfsd: kmalloc failed, freeing readahead buffers\n");
2103 nfsd_racache_shutdown();