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/fcntl.h>
20 #include <linux/namei.h>
21 #include <linux/delay.h>
22 #include <linux/fsnotify.h>
23 #include <linux/posix_acl_xattr.h>
24 #include <linux/xattr.h>
25 #include <linux/jhash.h>
26 #include <linux/ima.h>
27 #include <linux/slab.h>
28 #include <asm/uaccess.h>
29 #include <linux/exportfs.h>
30 #include <linux/writeback.h>
31 #include <linux/security.h>
35 #endif /* CONFIG_NFSD_V3 */
40 #endif /* CONFIG_NFSD_V4 */
45 #define NFSDDBG_FACILITY NFSDDBG_FILEOP
49 * This is a cache of readahead params that help us choose the proper
50 * readahead strategy. Initially, we set all readahead parameters to 0
51 * and let the VFS handle things.
52 * If you increase the number of cached files very much, you'll need to
53 * add a hash table here.
56 struct raparms *p_next;
61 struct file_ra_state p_ra;
62 unsigned int p_hindex;
65 struct raparm_hbucket {
66 struct raparms *pb_head;
68 } ____cacheline_aligned_in_smp;
70 #define RAPARM_HASH_BITS 4
71 #define RAPARM_HASH_SIZE (1<<RAPARM_HASH_BITS)
72 #define RAPARM_HASH_MASK (RAPARM_HASH_SIZE-1)
73 static struct raparm_hbucket raparm_hash[RAPARM_HASH_SIZE];
76 * Called from nfsd_lookup and encode_dirent. Check if we have crossed
78 * Returns -EAGAIN or -ETIMEDOUT leaving *dpp and *expp unchanged,
79 * or nfs_ok having possibly changed *dpp and *expp
82 nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
83 struct svc_export **expp)
85 struct svc_export *exp = *expp, *exp2 = NULL;
86 struct dentry *dentry = *dpp;
87 struct path path = {.mnt = mntget(exp->ex_path.mnt),
88 .dentry = dget(dentry)};
91 err = follow_down(&path);
95 exp2 = rqst_exp_get_by_name(rqstp, &path);
99 * We normally allow NFS clients to continue
100 * "underneath" a mountpoint that is not exported.
101 * The exception is V4ROOT, where no traversal is ever
102 * allowed without an explicit export of the new
105 if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
110 if (nfsd_v4client(rqstp) ||
111 (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
112 /* successfully crossed mount point */
114 * This is subtle: path.dentry is *not* on path.mnt
115 * at this point. The only reason we are safe is that
116 * original mnt is pinned down by exp, so we should
117 * put path *before* putting exp
120 path.dentry = dentry;
130 static void follow_to_parent(struct path *path)
134 while (path->dentry == path->mnt->mnt_root && follow_up(path))
136 dp = dget_parent(path->dentry);
141 static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
143 struct svc_export *exp2;
144 struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
145 .dentry = dget(dparent)};
147 follow_to_parent(&path);
149 exp2 = rqst_exp_parent(rqstp, &path);
150 if (PTR_ERR(exp2) == -ENOENT) {
151 *dentryp = dget(dparent);
152 } else if (IS_ERR(exp2)) {
154 return PTR_ERR(exp2);
156 *dentryp = dget(path.dentry);
165 * For nfsd purposes, we treat V4ROOT exports as though there was an
166 * export at *every* directory.
168 int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
170 if (d_mountpoint(dentry))
172 if (nfsd4_is_junction(dentry))
174 if (!(exp->ex_flags & NFSEXP_V4ROOT))
176 return dentry->d_inode != NULL;
180 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
181 const char *name, unsigned int len,
182 struct svc_export **exp_ret, struct dentry **dentry_ret)
184 struct svc_export *exp;
185 struct dentry *dparent;
186 struct dentry *dentry;
189 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
191 dparent = fhp->fh_dentry;
192 exp = fhp->fh_export;
195 /* Lookup the name, but don't follow links */
196 if (isdotent(name, len)) {
198 dentry = dget(dparent);
199 else if (dparent != exp->ex_path.dentry)
200 dentry = dget_parent(dparent);
201 else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
202 dentry = dget(dparent); /* .. == . just like at / */
204 /* checking mountpoint crossing is very different when stepping up */
205 host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
211 dentry = lookup_one_len(name, dparent, len);
212 host_err = PTR_ERR(dentry);
216 * check if we have crossed a mount point ...
218 if (nfsd_mountpoint(dentry, exp)) {
219 if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
225 *dentry_ret = dentry;
231 return nfserrno(host_err);
235 * Look up one component of a pathname.
236 * N.B. After this call _both_ fhp and resfh need an fh_put
238 * If the lookup would cross a mountpoint, and the mounted filesystem
239 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
240 * accepted as it stands and the mounted directory is
241 * returned. Otherwise the covered directory is returned.
242 * NOTE: this mountpoint crossing is not supported properly by all
243 * clients and is explicitly disallowed for NFSv3
244 * NeilBrown <neilb@cse.unsw.edu.au>
247 nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
248 unsigned int len, struct svc_fh *resfh)
250 struct svc_export *exp;
251 struct dentry *dentry;
254 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
257 err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
260 err = check_nfsd_access(exp, rqstp);
264 * Note: we compose the file handle now, but as the
265 * dentry may be negative, it may need to be updated.
267 err = fh_compose(resfh, exp, dentry, fhp);
268 if (!err && !dentry->d_inode)
276 static int nfsd_break_lease(struct inode *inode)
278 if (!S_ISREG(inode->i_mode))
280 return break_lease(inode, O_WRONLY | O_NONBLOCK);
284 * Commit metadata changes to stable storage.
287 commit_metadata(struct svc_fh *fhp)
289 struct inode *inode = fhp->fh_dentry->d_inode;
290 const struct export_operations *export_ops = inode->i_sb->s_export_op;
292 if (!EX_ISSYNC(fhp->fh_export))
295 if (export_ops->commit_metadata)
296 return export_ops->commit_metadata(inode);
297 return sync_inode_metadata(inode, 1);
301 * Set various file attributes.
302 * N.B. After this call fhp needs an fh_put
305 nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
306 int check_guard, time_t guardtime)
308 struct dentry *dentry;
310 int accmode = NFSD_MAY_SATTR;
316 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
317 accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
318 if (iap->ia_valid & ATTR_SIZE)
322 err = fh_verify(rqstp, fhp, ftype, accmode);
326 dentry = fhp->fh_dentry;
327 inode = dentry->d_inode;
329 /* Ignore any mode updates on symlinks */
330 if (S_ISLNK(inode->i_mode))
331 iap->ia_valid &= ~ATTR_MODE;
337 * NFSv2 does not differentiate between "set-[ac]time-to-now"
338 * which only requires access, and "set-[ac]time-to-X" which
339 * requires ownership.
340 * So if it looks like it might be "set both to the same time which
341 * is close to now", and if inode_change_ok fails, then we
342 * convert to "set to now" instead of "set to explicit time"
344 * We only call inode_change_ok as the last test as technically
345 * it is not an interface that we should be using. It is only
346 * valid if the filesystem does not define it's own i_op->setattr.
348 #define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
349 #define MAX_TOUCH_TIME_ERROR (30*60)
350 if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET &&
351 iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec) {
355 * Now just make sure time is in the right ballpark.
356 * Solaris, at least, doesn't seem to care what the time
357 * request is. We require it be within 30 minutes of now.
359 time_t delta = iap->ia_atime.tv_sec - get_seconds();
362 if (delta < MAX_TOUCH_TIME_ERROR &&
363 inode_change_ok(inode, iap) != 0) {
365 * Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
366 * This will cause notify_change to set these times
369 iap->ia_valid &= ~BOTH_TIME_SET;
374 * The size case is special.
375 * It changes the file as well as the attributes.
377 if (iap->ia_valid & ATTR_SIZE) {
378 if (iap->ia_size < inode->i_size) {
379 err = nfsd_permission(rqstp, fhp->fh_export, dentry,
380 NFSD_MAY_TRUNC|NFSD_MAY_OWNER_OVERRIDE);
385 host_err = get_write_access(inode);
390 host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
392 put_write_access(inode);
397 /* sanitize the mode change */
398 if (iap->ia_valid & ATTR_MODE) {
399 iap->ia_mode &= S_IALLUGO;
400 iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
403 /* Revoke setuid/setgid on chown */
404 if (!S_ISDIR(inode->i_mode) &&
405 (((iap->ia_valid & ATTR_UID) && !uid_eq(iap->ia_uid, inode->i_uid)) ||
406 ((iap->ia_valid & ATTR_GID) && !gid_eq(iap->ia_gid, inode->i_gid)))) {
407 iap->ia_valid |= ATTR_KILL_PRIV;
408 if (iap->ia_valid & ATTR_MODE) {
409 /* we're setting mode too, just clear the s*id bits */
410 iap->ia_mode &= ~S_ISUID;
411 if (iap->ia_mode & S_IXGRP)
412 iap->ia_mode &= ~S_ISGID;
414 /* set ATTR_KILL_* bits and let VFS handle it */
415 iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
419 /* Change the attributes. */
421 iap->ia_valid |= ATTR_CTIME;
423 err = nfserr_notsync;
424 if (!check_guard || guardtime == inode->i_ctime.tv_sec) {
425 host_err = nfsd_break_lease(inode);
430 host_err = notify_change(dentry, iap);
431 err = nfserrno(host_err);
435 put_write_access(inode);
437 commit_metadata(fhp);
442 err = nfserrno(host_err);
446 #if defined(CONFIG_NFSD_V2_ACL) || \
447 defined(CONFIG_NFSD_V3_ACL) || \
448 defined(CONFIG_NFSD_V4)
449 static ssize_t nfsd_getxattr(struct dentry *dentry, char *key, void **buf)
454 buflen = vfs_getxattr(dentry, key, NULL, 0);
458 *buf = kmalloc(buflen, GFP_KERNEL);
462 ret = vfs_getxattr(dentry, key, *buf, buflen);
469 #if defined(CONFIG_NFSD_V4)
471 set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key)
478 buflen = posix_acl_xattr_size(pacl->a_count);
479 buf = kmalloc(buflen, GFP_KERNEL);
484 len = posix_acl_to_xattr(&init_user_ns, pacl, buf, buflen);
490 error = vfs_setxattr(dentry, key, buf, len, 0);
497 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
498 struct nfs4_acl *acl)
502 struct dentry *dentry;
504 struct posix_acl *pacl = NULL, *dpacl = NULL;
505 unsigned int flags = 0;
508 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR);
512 dentry = fhp->fh_dentry;
513 inode = dentry->d_inode;
514 if (S_ISDIR(inode->i_mode))
515 flags = NFS4_ACL_DIR;
517 host_error = nfs4_acl_nfsv4_to_posix(acl, &pacl, &dpacl, flags);
518 if (host_error == -EINVAL) {
519 return nfserr_attrnotsupp;
520 } else if (host_error < 0)
523 host_error = set_nfsv4_acl_one(dentry, pacl, POSIX_ACL_XATTR_ACCESS);
527 if (S_ISDIR(inode->i_mode))
528 host_error = set_nfsv4_acl_one(dentry, dpacl, POSIX_ACL_XATTR_DEFAULT);
531 posix_acl_release(pacl);
532 posix_acl_release(dpacl);
534 if (host_error == -EOPNOTSUPP)
535 return nfserr_attrnotsupp;
537 return nfserrno(host_error);
540 static struct posix_acl *
541 _get_posix_acl(struct dentry *dentry, char *key)
544 struct posix_acl *pacl = NULL;
547 buflen = nfsd_getxattr(dentry, key, &buf);
551 return ERR_PTR(buflen);
553 pacl = posix_acl_from_xattr(&init_user_ns, buf, buflen);
559 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl)
561 struct inode *inode = dentry->d_inode;
563 struct posix_acl *pacl = NULL, *dpacl = NULL;
564 unsigned int flags = 0;
566 pacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_ACCESS);
567 if (IS_ERR(pacl) && PTR_ERR(pacl) == -ENODATA)
568 pacl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
570 error = PTR_ERR(pacl);
575 if (S_ISDIR(inode->i_mode)) {
576 dpacl = _get_posix_acl(dentry, POSIX_ACL_XATTR_DEFAULT);
577 if (IS_ERR(dpacl) && PTR_ERR(dpacl) == -ENODATA)
579 else if (IS_ERR(dpacl)) {
580 error = PTR_ERR(dpacl);
584 flags = NFS4_ACL_DIR;
587 *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags);
589 error = PTR_ERR(*acl);
593 posix_acl_release(pacl);
594 posix_acl_release(dpacl);
599 * NFS junction information is stored in an extended attribute.
601 #define NFSD_JUNCTION_XATTR_NAME XATTR_TRUSTED_PREFIX "junction.nfs"
604 * nfsd4_is_junction - Test if an object could be an NFS junction
606 * @dentry: object to test
608 * Returns 1 if "dentry" appears to contain NFS junction information.
609 * Otherwise 0 is returned.
611 int nfsd4_is_junction(struct dentry *dentry)
613 struct inode *inode = dentry->d_inode;
617 if (inode->i_mode & S_IXUGO)
619 if (!(inode->i_mode & S_ISVTX))
621 if (vfs_getxattr(dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0)
625 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
626 __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp,
627 struct xdr_netobj *label)
631 struct dentry *dentry;
633 error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR);
637 dentry = fhp->fh_dentry;
639 mutex_lock(&dentry->d_inode->i_mutex);
640 host_error = security_inode_setsecctx(dentry, label->data, label->len);
641 mutex_unlock(&dentry->d_inode->i_mutex);
642 return nfserrno(host_error);
645 __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp,
646 struct xdr_netobj *label)
648 return nfserr_notsupp;
652 #endif /* defined(CONFIG_NFSD_V4) */
654 #ifdef CONFIG_NFSD_V3
656 * Check server access rights to a file system object
662 static struct accessmap nfs3_regaccess[] = {
663 { NFS3_ACCESS_READ, NFSD_MAY_READ },
664 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
665 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC },
666 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE },
671 static struct accessmap nfs3_diraccess[] = {
672 { NFS3_ACCESS_READ, NFSD_MAY_READ },
673 { NFS3_ACCESS_LOOKUP, NFSD_MAY_EXEC },
674 { NFS3_ACCESS_MODIFY, NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC},
675 { NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE },
676 { NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE },
681 static struct accessmap nfs3_anyaccess[] = {
682 /* Some clients - Solaris 2.6 at least, make an access call
683 * to the server to check for access for things like /dev/null
684 * (which really, the server doesn't care about). So
685 * We provide simple access checking for them, looking
686 * mainly at mode bits, and we make sure to ignore read-only
689 { NFS3_ACCESS_READ, NFSD_MAY_READ },
690 { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
691 { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
692 { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
698 nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported)
700 struct accessmap *map;
701 struct svc_export *export;
702 struct dentry *dentry;
703 u32 query, result = 0, sresult = 0;
706 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
710 export = fhp->fh_export;
711 dentry = fhp->fh_dentry;
713 if (S_ISREG(dentry->d_inode->i_mode))
714 map = nfs3_regaccess;
715 else if (S_ISDIR(dentry->d_inode->i_mode))
716 map = nfs3_diraccess;
718 map = nfs3_anyaccess;
722 for (; map->access; map++) {
723 if (map->access & query) {
726 sresult |= map->access;
728 err2 = nfsd_permission(rqstp, export, dentry, map->how);
731 result |= map->access;
734 /* the following error codes just mean the access was not allowed,
735 * rather than an error occurred */
739 /* simply don't "or" in the access bit. */
749 *supported = sresult;
754 #endif /* CONFIG_NFSD_V3 */
756 static int nfsd_open_break_lease(struct inode *inode, int access)
760 if (access & NFSD_MAY_NOT_BREAK_LEASE)
762 mode = (access & NFSD_MAY_WRITE) ? O_WRONLY : O_RDONLY;
763 return break_lease(inode, mode | O_NONBLOCK);
767 * Open an existing file or directory.
768 * The may_flags argument indicates the type of open (read/write/lock)
769 * and additional flags.
770 * N.B. After this call fhp needs an fh_put
773 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
774 int may_flags, struct file **filp)
778 int flags = O_RDONLY|O_LARGEFILE;
782 validate_process_creds();
785 * If we get here, then the client has already done an "open",
786 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
787 * in case a chmod has now revoked permission.
789 * Arguably we should also allow the owner override for
790 * directories, but we never have and it doesn't seem to have
791 * caused anyone a problem. If we were to change this, note
792 * also that our filldir callbacks would need a variant of
793 * lookup_one_len that doesn't check permissions.
796 may_flags |= NFSD_MAY_OWNER_OVERRIDE;
797 err = fh_verify(rqstp, fhp, type, may_flags);
801 path.mnt = fhp->fh_export->ex_path.mnt;
802 path.dentry = fhp->fh_dentry;
803 inode = path.dentry->d_inode;
805 /* Disallow write access to files with the append-only bit set
806 * or any access when mandatory locking enabled
809 if (IS_APPEND(inode) && (may_flags & NFSD_MAY_WRITE))
812 * We must ignore files (but only files) which might have mandatory
813 * locks on them because there is no way to know if the accesser has
816 if (S_ISREG((inode)->i_mode) && mandatory_lock(inode))
822 host_err = nfsd_open_break_lease(inode, may_flags);
823 if (host_err) /* NOMEM or WOULDBLOCK */
826 if (may_flags & NFSD_MAY_WRITE) {
827 if (may_flags & NFSD_MAY_READ)
828 flags = O_RDWR|O_LARGEFILE;
830 flags = O_WRONLY|O_LARGEFILE;
832 *filp = dentry_open(&path, flags, current_cred());
834 host_err = PTR_ERR(*filp);
836 host_err = ima_file_check(*filp, may_flags);
838 if (may_flags & NFSD_MAY_64BIT_COOKIE)
839 (*filp)->f_mode |= FMODE_64BITHASH;
841 (*filp)->f_mode |= FMODE_32BITHASH;
845 err = nfserrno(host_err);
847 validate_process_creds();
855 nfsd_close(struct file *filp)
861 * Obtain the readahead parameters for the file
862 * specified by (dev, ino).
865 static inline struct raparms *
866 nfsd_get_raparms(dev_t dev, ino_t ino)
868 struct raparms *ra, **rap, **frap = NULL;
871 struct raparm_hbucket *rab;
873 hash = jhash_2words(dev, ino, 0xfeedbeef) & RAPARM_HASH_MASK;
874 rab = &raparm_hash[hash];
876 spin_lock(&rab->pb_lock);
877 for (rap = &rab->pb_head; (ra = *rap); rap = &ra->p_next) {
878 if (ra->p_ino == ino && ra->p_dev == dev)
881 if (ra->p_count == 0)
884 depth = nfsdstats.ra_size;
886 spin_unlock(&rab->pb_lock);
896 if (rap != &rab->pb_head) {
898 ra->p_next = rab->pb_head;
902 nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++;
903 spin_unlock(&rab->pb_lock);
908 * Grab and keep cached pages associated with a file in the svc_rqst
909 * so that they can be passed to the network sendmsg/sendpage routines
910 * directly. They will be released after the sending has completed.
913 nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
914 struct splice_desc *sd)
916 struct svc_rqst *rqstp = sd->u.data;
917 struct page **pp = rqstp->rq_next_page;
918 struct page *page = buf->page;
923 if (rqstp->rq_res.page_len == 0) {
925 put_page(*rqstp->rq_next_page);
926 *(rqstp->rq_next_page++) = page;
927 rqstp->rq_res.page_base = buf->offset;
928 rqstp->rq_res.page_len = size;
929 } else if (page != pp[-1]) {
931 if (*rqstp->rq_next_page)
932 put_page(*rqstp->rq_next_page);
933 *(rqstp->rq_next_page++) = page;
934 rqstp->rq_res.page_len += size;
936 rqstp->rq_res.page_len += size;
941 static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
942 struct splice_desc *sd)
944 return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
948 nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
949 loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
957 if (file->f_op->splice_read && rqstp->rq_splice_ok) {
958 struct splice_desc sd = {
965 rqstp->rq_next_page = rqstp->rq_respages + 1;
966 host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
970 host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
975 nfsdstats.io_read += host_err;
978 fsnotify_access(file);
980 err = nfserrno(host_err);
984 static void kill_suid(struct dentry *dentry)
987 ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
989 mutex_lock(&dentry->d_inode->i_mutex);
990 notify_change(dentry, &ia);
991 mutex_unlock(&dentry->d_inode->i_mutex);
995 * Gathered writes: If another process is currently writing to the file,
996 * there's a high chance this is another nfsd (triggered by a bulk write
997 * from a client's biod). Rather than syncing the file with each write
998 * request, we sleep for 10 msec.
1000 * I don't know if this roughly approximates C. Juszak's idea of
1001 * gathered writes, but it's a nice and simple solution (IMHO), and it
1004 * Note: we do this only in the NFSv2 case, since v3 and higher have a
1005 * better tool (separate unstable writes and commits) for solving this
1008 static int wait_for_concurrent_writes(struct file *file)
1010 struct inode *inode = file_inode(file);
1011 static ino_t last_ino;
1012 static dev_t last_dev;
1015 if (atomic_read(&inode->i_writecount) > 1
1016 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
1017 dprintk("nfsd: write defer %d\n", task_pid_nr(current));
1019 dprintk("nfsd: write resume %d\n", task_pid_nr(current));
1022 if (inode->i_state & I_DIRTY) {
1023 dprintk("nfsd: write sync %d\n", task_pid_nr(current));
1024 err = vfs_fsync(file, 0);
1026 last_ino = inode->i_ino;
1027 last_dev = inode->i_sb->s_dev;
1032 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1033 loff_t offset, struct kvec *vec, int vlen,
1034 unsigned long *cnt, int *stablep)
1036 struct svc_export *exp;
1037 struct dentry *dentry;
1038 struct inode *inode;
1042 int stable = *stablep;
1044 loff_t pos = offset;
1046 dentry = file->f_path.dentry;
1047 inode = dentry->d_inode;
1048 exp = fhp->fh_export;
1050 use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
1052 if (!EX_ISSYNC(exp))
1055 /* Write the data. */
1056 oldfs = get_fs(); set_fs(KERNEL_DS);
1057 host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos);
1062 nfsdstats.io_write += host_err;
1063 fsnotify_modify(file);
1065 /* clear setuid/setgid flag after write */
1066 if (inode->i_mode & (S_ISUID | S_ISGID))
1071 host_err = wait_for_concurrent_writes(file);
1073 host_err = vfs_fsync_range(file, offset, offset+*cnt, 0);
1077 dprintk("nfsd: write complete host_err=%d\n", host_err);
1081 err = nfserrno(host_err);
1086 * Read data from a file. count must contain the requested read count
1087 * on entry. On return, *count contains the number of bytes actually read.
1088 * N.B. After this call fhp needs an fh_put
1090 __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
1091 loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
1094 struct inode *inode;
1098 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
1102 inode = file_inode(file);
1104 /* Get readahead parameters */
1105 ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
1107 if (ra && ra->p_set)
1108 file->f_ra = ra->p_ra;
1110 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1112 /* Write back readahead params */
1114 struct raparm_hbucket *rab = &raparm_hash[ra->p_hindex];
1115 spin_lock(&rab->pb_lock);
1116 ra->p_ra = file->f_ra;
1119 spin_unlock(&rab->pb_lock);
1126 /* As above, but use the provided file descriptor. */
1128 nfsd_read_file(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1129 loff_t offset, struct kvec *vec, int vlen,
1130 unsigned long *count)
1135 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1136 NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
1139 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1140 } else /* Note file may still be NULL in NFSv4 special stateid case: */
1141 err = nfsd_read(rqstp, fhp, offset, vec, vlen, count);
1147 * Write data to a file.
1148 * The stable flag requests synchronous writes.
1149 * N.B. After this call fhp needs an fh_put
1152 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1153 loff_t offset, struct kvec *vec, int vlen, unsigned long *cnt,
1159 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1160 NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE);
1163 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt,
1166 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
1171 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen,
1179 #ifdef CONFIG_NFSD_V3
1181 * Commit all pending writes to stable storage.
1183 * Note: we only guarantee that data that lies within the range specified
1184 * by the 'offset' and 'count' parameters will be synced.
1186 * Unfortunately we cannot lock the file to make sure we return full WCC
1187 * data to the client, as locking happens lower down in the filesystem.
1190 nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
1191 loff_t offset, unsigned long count)
1194 loff_t end = LLONG_MAX;
1195 __be32 err = nfserr_inval;
1200 end = offset + (loff_t)count - 1;
1205 err = nfsd_open(rqstp, fhp, S_IFREG,
1206 NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &file);
1209 if (EX_ISSYNC(fhp->fh_export)) {
1210 int err2 = vfs_fsync_range(file, offset, end, 0);
1212 if (err2 != -EINVAL)
1213 err = nfserrno(err2);
1215 err = nfserr_notsupp;
1222 #endif /* CONFIG_NFSD_V3 */
1225 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
1229 * Mode has already been set earlier in create:
1231 iap->ia_valid &= ~ATTR_MODE;
1233 * Setting uid/gid works only for root. Irix appears to
1234 * send along the gid on create when it tries to implement
1235 * setgid directories via NFS:
1237 if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID))
1238 iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
1240 return nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
1244 /* HPUX client sometimes creates a file in mode 000, and sets size to 0.
1245 * setting size to 0 may fail for some specific file systems by the permission
1246 * checking which requires WRITE permission but the mode is 000.
1247 * we ignore the resizing(to 0) on the just new created file, since the size is
1248 * 0 after file created.
1250 * call this only after vfs_create() is called.
1253 nfsd_check_ignore_resizing(struct iattr *iap)
1255 if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
1256 iap->ia_valid &= ~ATTR_SIZE;
1260 * Create a file (regular, directory, device, fifo); UNIX sockets
1261 * not yet implemented.
1262 * If the response fh has been verified, the parent directory should
1263 * already be locked. Note that the parent directory is left locked.
1265 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1268 nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1269 char *fname, int flen, struct iattr *iap,
1270 int type, dev_t rdev, struct svc_fh *resfhp)
1272 struct dentry *dentry, *dchild = NULL;
1282 if (isdotent(fname, flen))
1285 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1289 dentry = fhp->fh_dentry;
1290 dirp = dentry->d_inode;
1292 err = nfserr_notdir;
1293 if (!dirp->i_op->lookup)
1296 * Check whether the response file handle has been verified yet.
1297 * If it has, the parent directory should already be locked.
1299 if (!resfhp->fh_dentry) {
1300 host_err = fh_want_write(fhp);
1304 /* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */
1305 fh_lock_nested(fhp, I_MUTEX_PARENT);
1306 dchild = lookup_one_len(fname, dentry, flen);
1307 host_err = PTR_ERR(dchild);
1310 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1314 /* called from nfsd_proc_create */
1315 dchild = dget(resfhp->fh_dentry);
1316 if (!fhp->fh_locked) {
1317 /* not actually possible */
1319 "nfsd_create: parent %s/%s not locked!\n",
1320 dentry->d_parent->d_name.name,
1321 dentry->d_name.name);
1327 * Make sure the child dentry is still negative ...
1330 if (dchild->d_inode) {
1331 dprintk("nfsd_create: dentry %s/%s not negative!\n",
1332 dentry->d_name.name, dchild->d_name.name);
1336 if (!(iap->ia_valid & ATTR_MODE))
1338 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
1341 if (!S_ISREG(type) && !S_ISDIR(type) && !special_file(type)) {
1342 printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
1348 * Get the dir op function pointer.
1354 host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
1356 nfsd_check_ignore_resizing(iap);
1359 host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
1365 host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
1371 err = nfsd_create_setattr(rqstp, resfhp, iap);
1374 * nfsd_setattr already committed the child. Transactional filesystems
1375 * had a chance to commit changes for both parent and child
1376 * simultaneously making the following commit_metadata a noop.
1378 err2 = nfserrno(commit_metadata(fhp));
1382 * Update the file handle to get the new inode info.
1385 err = fh_update(resfhp);
1387 if (dchild && !IS_ERR(dchild))
1392 err = nfserrno(host_err);
1396 #ifdef CONFIG_NFSD_V3
1398 static inline int nfsd_create_is_exclusive(int createmode)
1400 return createmode == NFS3_CREATE_EXCLUSIVE
1401 || createmode == NFS4_CREATE_EXCLUSIVE4_1;
1405 * NFSv3 and NFSv4 version of nfsd_create
1408 do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1409 char *fname, int flen, struct iattr *iap,
1410 struct svc_fh *resfhp, int createmode, u32 *verifier,
1411 bool *truncp, bool *created)
1413 struct dentry *dentry, *dchild = NULL;
1417 __u32 v_mtime=0, v_atime=0;
1423 if (isdotent(fname, flen))
1425 if (!(iap->ia_valid & ATTR_MODE))
1427 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
1431 dentry = fhp->fh_dentry;
1432 dirp = dentry->d_inode;
1434 /* Get all the sanity checks out of the way before
1435 * we lock the parent. */
1436 err = nfserr_notdir;
1437 if (!dirp->i_op->lookup)
1440 host_err = fh_want_write(fhp);
1444 fh_lock_nested(fhp, I_MUTEX_PARENT);
1447 * Compose the response file handle.
1449 dchild = lookup_one_len(fname, dentry, flen);
1450 host_err = PTR_ERR(dchild);
1454 /* If file doesn't exist, check for permissions to create one */
1455 if (!dchild->d_inode) {
1456 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1461 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1465 if (nfsd_create_is_exclusive(createmode)) {
1466 /* solaris7 gets confused (bugid 4218508) if these have
1467 * the high bit set, so just clear the high bits. If this is
1468 * ever changed to use different attrs for storing the
1469 * verifier, then do_open_lookup() will also need to be fixed
1472 v_mtime = verifier[0]&0x7fffffff;
1473 v_atime = verifier[1]&0x7fffffff;
1476 if (dchild->d_inode) {
1479 switch (createmode) {
1480 case NFS3_CREATE_UNCHECKED:
1481 if (! S_ISREG(dchild->d_inode->i_mode))
1484 /* in nfsv4, we need to treat this case a little
1485 * differently. we don't want to truncate the
1486 * file now; this would be wrong if the OPEN
1487 * fails for some other reason. furthermore,
1488 * if the size is nonzero, we should ignore it
1489 * according to spec!
1491 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size;
1494 iap->ia_valid &= ATTR_SIZE;
1498 case NFS3_CREATE_EXCLUSIVE:
1499 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime
1500 && dchild->d_inode->i_atime.tv_sec == v_atime
1501 && dchild->d_inode->i_size == 0 ) {
1506 case NFS4_CREATE_EXCLUSIVE4_1:
1507 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime
1508 && dchild->d_inode->i_atime.tv_sec == v_atime
1509 && dchild->d_inode->i_size == 0 ) {
1515 case NFS3_CREATE_GUARDED:
1522 host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
1530 nfsd_check_ignore_resizing(iap);
1532 if (nfsd_create_is_exclusive(createmode)) {
1533 /* Cram the verifier into atime/mtime */
1534 iap->ia_valid = ATTR_MTIME|ATTR_ATIME
1535 | ATTR_MTIME_SET|ATTR_ATIME_SET;
1536 /* XXX someone who knows this better please fix it for nsec */
1537 iap->ia_mtime.tv_sec = v_mtime;
1538 iap->ia_atime.tv_sec = v_atime;
1539 iap->ia_mtime.tv_nsec = 0;
1540 iap->ia_atime.tv_nsec = 0;
1544 err = nfsd_create_setattr(rqstp, resfhp, iap);
1547 * nfsd_setattr already committed the child (and possibly also the parent).
1550 err = nfserrno(commit_metadata(fhp));
1553 * Update the filehandle to get the new inode info.
1556 err = fh_update(resfhp);
1560 if (dchild && !IS_ERR(dchild))
1566 err = nfserrno(host_err);
1569 #endif /* CONFIG_NFSD_V3 */
1572 * Read a symlink. On entry, *lenp must contain the maximum path length that
1573 * fits into the buffer. On return, it contains the true length.
1574 * N.B. After this call fhp needs an fh_put
1577 nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
1579 struct inode *inode;
1585 err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
1589 path.mnt = fhp->fh_export->ex_path.mnt;
1590 path.dentry = fhp->fh_dentry;
1591 inode = path.dentry->d_inode;
1594 if (!inode->i_op->readlink)
1598 /* N.B. Why does this call need a get_fs()??
1599 * Remove the set_fs and watch the fireworks:-) --okir
1602 oldfs = get_fs(); set_fs(KERNEL_DS);
1603 host_err = inode->i_op->readlink(path.dentry, (char __user *)buf, *lenp);
1614 err = nfserrno(host_err);
1619 * Create a symlink and look up its inode
1620 * N.B. After this call _both_ fhp and resfhp need an fh_put
1623 nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
1624 char *fname, int flen,
1625 char *path, int plen,
1626 struct svc_fh *resfhp,
1629 struct dentry *dentry, *dnew;
1637 if (isdotent(fname, flen))
1640 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1644 host_err = fh_want_write(fhp);
1649 dentry = fhp->fh_dentry;
1650 dnew = lookup_one_len(fname, dentry, flen);
1651 host_err = PTR_ERR(dnew);
1655 if (unlikely(path[plen] != 0)) {
1656 char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
1657 if (path_alloced == NULL)
1660 strncpy(path_alloced, path, plen);
1661 path_alloced[plen] = 0;
1662 host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced);
1663 kfree(path_alloced);
1666 host_err = vfs_symlink(dentry->d_inode, dnew, path);
1667 err = nfserrno(host_err);
1669 err = nfserrno(commit_metadata(fhp));
1674 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
1676 if (err==0) err = cerr;
1681 err = nfserrno(host_err);
1687 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1690 nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
1691 char *name, int len, struct svc_fh *tfhp)
1693 struct dentry *ddir, *dnew, *dold;
1698 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
1701 err = fh_verify(rqstp, tfhp, 0, NFSD_MAY_NOP);
1705 if (S_ISDIR(tfhp->fh_dentry->d_inode->i_mode))
1711 if (isdotent(name, len))
1714 host_err = fh_want_write(tfhp);
1716 err = nfserrno(host_err);
1720 fh_lock_nested(ffhp, I_MUTEX_PARENT);
1721 ddir = ffhp->fh_dentry;
1722 dirp = ddir->d_inode;
1724 dnew = lookup_one_len(name, ddir, len);
1725 host_err = PTR_ERR(dnew);
1729 dold = tfhp->fh_dentry;
1734 host_err = nfsd_break_lease(dold->d_inode);
1736 err = nfserrno(host_err);
1739 host_err = vfs_link(dold, dirp, dnew);
1741 err = nfserrno(commit_metadata(ffhp));
1743 err = nfserrno(commit_metadata(tfhp));
1745 if (host_err == -EXDEV && rqstp->rq_vers == 2)
1748 err = nfserrno(host_err);
1754 fh_drop_write(tfhp);
1759 err = nfserrno(host_err);
1765 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1768 nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
1769 struct svc_fh *tfhp, char *tname, int tlen)
1771 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
1772 struct inode *fdir, *tdir;
1776 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
1779 err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
1783 fdentry = ffhp->fh_dentry;
1784 fdir = fdentry->d_inode;
1786 tdentry = tfhp->fh_dentry;
1787 tdir = tdentry->d_inode;
1790 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
1793 host_err = fh_want_write(ffhp);
1795 err = nfserrno(host_err);
1799 /* cannot use fh_lock as we need deadlock protective ordering
1800 * so do it by hand */
1801 trap = lock_rename(tdentry, fdentry);
1802 ffhp->fh_locked = tfhp->fh_locked = 1;
1806 odentry = lookup_one_len(fname, fdentry, flen);
1807 host_err = PTR_ERR(odentry);
1808 if (IS_ERR(odentry))
1812 if (!odentry->d_inode)
1815 if (odentry == trap)
1818 ndentry = lookup_one_len(tname, tdentry, tlen);
1819 host_err = PTR_ERR(ndentry);
1820 if (IS_ERR(ndentry))
1822 host_err = -ENOTEMPTY;
1823 if (ndentry == trap)
1827 if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
1829 if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry)
1832 host_err = nfsd_break_lease(odentry->d_inode);
1835 if (ndentry->d_inode) {
1836 host_err = nfsd_break_lease(ndentry->d_inode);
1840 host_err = vfs_rename(fdir, odentry, tdir, ndentry);
1842 host_err = commit_metadata(tfhp);
1844 host_err = commit_metadata(ffhp);
1851 err = nfserrno(host_err);
1853 /* we cannot reply on fh_unlock on the two filehandles,
1854 * as that would do the wrong thing if the two directories
1855 * were the same, so again we do it by hand
1857 fill_post_wcc(ffhp);
1858 fill_post_wcc(tfhp);
1859 unlock_rename(tdentry, fdentry);
1860 ffhp->fh_locked = tfhp->fh_locked = 0;
1861 fh_drop_write(ffhp);
1868 * Unlink a file or directory
1869 * N.B. After this call fhp needs an fh_put
1872 nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
1873 char *fname, int flen)
1875 struct dentry *dentry, *rdentry;
1881 if (!flen || isdotent(fname, flen))
1883 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
1887 host_err = fh_want_write(fhp);
1891 fh_lock_nested(fhp, I_MUTEX_PARENT);
1892 dentry = fhp->fh_dentry;
1893 dirp = dentry->d_inode;
1895 rdentry = lookup_one_len(fname, dentry, flen);
1896 host_err = PTR_ERR(rdentry);
1897 if (IS_ERR(rdentry))
1900 if (!rdentry->d_inode) {
1907 type = rdentry->d_inode->i_mode & S_IFMT;
1909 host_err = nfsd_break_lease(rdentry->d_inode);
1912 if (type != S_IFDIR)
1913 host_err = vfs_unlink(dirp, rdentry);
1915 host_err = vfs_rmdir(dirp, rdentry);
1917 host_err = commit_metadata(fhp);
1922 err = nfserrno(host_err);
1928 * We do this buffering because we must not call back into the file
1929 * system's ->lookup() method from the filldir callback. That may well
1930 * deadlock a number of file systems.
1932 * This is based heavily on the implementation of same in XFS.
1934 struct buffered_dirent {
1938 unsigned int d_type;
1942 struct readdir_data {
1943 struct dir_context ctx;
1949 static int nfsd_buffered_filldir(void *__buf, const char *name, int namlen,
1950 loff_t offset, u64 ino, unsigned int d_type)
1952 struct readdir_data *buf = __buf;
1953 struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
1954 unsigned int reclen;
1956 reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
1957 if (buf->used + reclen > PAGE_SIZE) {
1962 de->namlen = namlen;
1963 de->offset = offset;
1965 de->d_type = d_type;
1966 memcpy(de->name, name, namlen);
1967 buf->used += reclen;
1972 static __be32 nfsd_buffered_readdir(struct file *file, filldir_t func,
1973 struct readdir_cd *cdp, loff_t *offsetp)
1975 struct buffered_dirent *de;
1979 struct readdir_data buf = {
1980 .ctx.actor = nfsd_buffered_filldir,
1981 .dirent = (void *)__get_free_page(GFP_KERNEL)
1985 return nfserrno(-ENOMEM);
1990 struct inode *dir_inode = file_inode(file);
1991 unsigned int reclen;
1993 cdp->err = nfserr_eof; /* will be cleared on successful read */
1997 host_err = iterate_dir(file, &buf.ctx);
2010 * Various filldir functions may end up calling back into
2011 * lookup_one_len() and the file system's ->lookup() method.
2012 * These expect i_mutex to be held, as it would within readdir.
2014 host_err = mutex_lock_killable(&dir_inode->i_mutex);
2018 de = (struct buffered_dirent *)buf.dirent;
2020 offset = de->offset;
2022 if (func(cdp, de->name, de->namlen, de->offset,
2023 de->ino, de->d_type))
2026 if (cdp->err != nfs_ok)
2029 reclen = ALIGN(sizeof(*de) + de->namlen,
2032 de = (struct buffered_dirent *)((char *)de + reclen);
2034 mutex_unlock(&dir_inode->i_mutex);
2035 if (size > 0) /* We bailed out early */
2038 offset = vfs_llseek(file, 0, SEEK_CUR);
2041 free_page((unsigned long)(buf.dirent));
2044 return nfserrno(host_err);
2051 * Read entries from a directory.
2052 * The NFSv3/4 verifier we ignore for now.
2055 nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
2056 struct readdir_cd *cdp, filldir_t func)
2060 loff_t offset = *offsetp;
2061 int may_flags = NFSD_MAY_READ;
2063 /* NFSv2 only supports 32 bit cookies */
2064 if (rqstp->rq_vers > 2)
2065 may_flags |= NFSD_MAY_64BIT_COOKIE;
2067 err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file);
2071 offset = vfs_llseek(file, offset, SEEK_SET);
2073 err = nfserrno((int)offset);
2077 err = nfsd_buffered_readdir(file, func, cdp, offsetp);
2079 if (err == nfserr_eof || err == nfserr_toosmall)
2080 err = nfs_ok; /* can still be found in ->err */
2088 * Get file system stats
2089 * N.B. After this call fhp needs an fh_put
2092 nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
2096 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
2098 struct path path = {
2099 .mnt = fhp->fh_export->ex_path.mnt,
2100 .dentry = fhp->fh_dentry,
2102 if (vfs_statfs(&path, stat))
2108 static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp)
2110 return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY;
2114 * Check for a user's access permissions to this inode.
2117 nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
2118 struct dentry *dentry, int acc)
2120 struct inode *inode = dentry->d_inode;
2123 if ((acc & NFSD_MAY_MASK) == NFSD_MAY_NOP)
2126 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
2128 (acc & NFSD_MAY_READ)? " read" : "",
2129 (acc & NFSD_MAY_WRITE)? " write" : "",
2130 (acc & NFSD_MAY_EXEC)? " exec" : "",
2131 (acc & NFSD_MAY_SATTR)? " sattr" : "",
2132 (acc & NFSD_MAY_TRUNC)? " trunc" : "",
2133 (acc & NFSD_MAY_LOCK)? " lock" : "",
2134 (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
2136 IS_IMMUTABLE(inode)? " immut" : "",
2137 IS_APPEND(inode)? " append" : "",
2138 __mnt_is_readonly(exp->ex_path.mnt)? " ro" : "");
2139 dprintk(" owner %d/%d user %d/%d\n",
2140 inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
2143 /* Normally we reject any write/sattr etc access on a read-only file
2144 * system. But if it is IRIX doing check on write-access for a
2145 * device special file, we ignore rofs.
2147 if (!(acc & NFSD_MAY_LOCAL_ACCESS))
2148 if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
2149 if (exp_rdonly(rqstp, exp) ||
2150 __mnt_is_readonly(exp->ex_path.mnt))
2152 if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode))
2155 if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
2158 if (acc & NFSD_MAY_LOCK) {
2159 /* If we cannot rely on authentication in NLM requests,
2160 * just allow locks, otherwise require read permission, or
2163 if (exp->ex_flags & NFSEXP_NOAUTHNLM)
2166 acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
2169 * The file owner always gets access permission for accesses that
2170 * would normally be checked at open time. This is to make
2171 * file access work even when the client has done a fchmod(fd, 0).
2173 * However, `cp foo bar' should fail nevertheless when bar is
2174 * readonly. A sensible way to do this might be to reject all
2175 * attempts to truncate a read-only file, because a creat() call
2176 * always implies file truncation.
2177 * ... but this isn't really fair. A process may reasonably call
2178 * ftruncate on an open file descriptor on a file with perm 000.
2179 * We must trust the client to do permission checking - using "ACCESS"
2182 if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
2183 uid_eq(inode->i_uid, current_fsuid()))
2186 /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
2187 err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
2189 /* Allow read access to binaries even when mode 111 */
2190 if (err == -EACCES && S_ISREG(inode->i_mode) &&
2191 (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
2192 acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
2193 err = inode_permission(inode, MAY_EXEC);
2195 return err? nfserrno(err) : 0;
2199 nfsd_racache_shutdown(void)
2201 struct raparms *raparm, *last_raparm;
2204 dprintk("nfsd: freeing readahead buffers.\n");
2206 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2207 raparm = raparm_hash[i].pb_head;
2209 last_raparm = raparm;
2210 raparm = raparm->p_next;
2213 raparm_hash[i].pb_head = NULL;
2217 * Initialize readahead param cache
2220 nfsd_racache_init(int cache_size)
2225 struct raparms **raparm = NULL;
2228 if (raparm_hash[0].pb_head)
2230 nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE);
2233 cache_size = nperbucket * RAPARM_HASH_SIZE;
2235 dprintk("nfsd: allocating %d readahead buffers.\n", cache_size);
2237 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2238 spin_lock_init(&raparm_hash[i].pb_lock);
2240 raparm = &raparm_hash[i].pb_head;
2241 for (j = 0; j < nperbucket; j++) {
2242 *raparm = kzalloc(sizeof(struct raparms), GFP_KERNEL);
2245 raparm = &(*raparm)->p_next;
2250 nfsdstats.ra_size = cache_size;
2254 dprintk("nfsd: kmalloc failed, freeing readahead buffers\n");
2255 nfsd_racache_shutdown();
2259 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
2261 nfsd_get_posix_acl(struct svc_fh *fhp, int type)
2263 struct inode *inode = fhp->fh_dentry->d_inode;
2267 struct posix_acl *acl;
2269 if (!IS_POSIXACL(inode))
2270 return ERR_PTR(-EOPNOTSUPP);
2273 case ACL_TYPE_ACCESS:
2274 name = POSIX_ACL_XATTR_ACCESS;
2276 case ACL_TYPE_DEFAULT:
2277 name = POSIX_ACL_XATTR_DEFAULT;
2280 return ERR_PTR(-EOPNOTSUPP);
2283 size = nfsd_getxattr(fhp->fh_dentry, name, &value);
2285 return ERR_PTR(size);
2287 acl = posix_acl_from_xattr(&init_user_ns, value, size);
2293 nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
2295 struct inode *inode = fhp->fh_dentry->d_inode;
2301 if (!IS_POSIXACL(inode) ||
2302 !inode->i_op->setxattr || !inode->i_op->removexattr)
2305 case ACL_TYPE_ACCESS:
2306 name = POSIX_ACL_XATTR_ACCESS;
2308 case ACL_TYPE_DEFAULT:
2309 name = POSIX_ACL_XATTR_DEFAULT;
2315 if (acl && acl->a_count) {
2316 size = posix_acl_xattr_size(acl->a_count);
2317 value = kmalloc(size, GFP_KERNEL);
2320 error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
2327 error = fh_want_write(fhp);
2331 error = vfs_setxattr(fhp->fh_dentry, name, value, size, 0);
2333 if (!S_ISDIR(inode->i_mode) && type == ACL_TYPE_DEFAULT)
2336 error = vfs_removexattr(fhp->fh_dentry, name);
2337 if (error == -ENODATA)
2347 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */