1 #define MSNFS /* HACK HACK */
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>
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 <linux/slab.h>
29 #include <asm/uaccess.h>
30 #include <linux/exportfs.h>
31 #include <linux/writeback.h>
35 #endif /* CONFIG_NFSD_V3 */
38 #include <linux/nfs4_acl.h>
39 #include <linux/nfsd_idmap.h>
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 while (d_mountpoint(path.dentry) && follow_down(&path))
94 exp2 = rqst_exp_get_by_name(rqstp, &path);
98 * We normally allow NFS clients to continue
99 * "underneath" a mountpoint that is not exported.
100 * The exception is V4ROOT, where no traversal is ever
101 * allowed without an explicit export of the new
104 if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
109 if (nfsd_v4client(rqstp) ||
110 (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
111 /* successfully crossed mount point */
113 * This is subtle: path.dentry is *not* on path.mnt
114 * at this point. The only reason we are safe is that
115 * original mnt is pinned down by exp, so we should
116 * put path *before* putting exp
119 path.dentry = dentry;
129 static void follow_to_parent(struct path *path)
133 while (path->dentry == path->mnt->mnt_root && follow_up(path))
135 dp = dget_parent(path->dentry);
140 static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
142 struct svc_export *exp2;
143 struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
144 .dentry = dget(dparent)};
146 follow_to_parent(&path);
148 exp2 = rqst_exp_parent(rqstp, &path);
149 if (PTR_ERR(exp2) == -ENOENT) {
150 *dentryp = dget(dparent);
151 } else if (IS_ERR(exp2)) {
153 return PTR_ERR(exp2);
155 *dentryp = dget(path.dentry);
164 * For nfsd purposes, we treat V4ROOT exports as though there was an
165 * export at *every* directory.
167 int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
169 if (d_mountpoint(dentry))
171 if (!(exp->ex_flags & NFSEXP_V4ROOT))
173 return dentry->d_inode != NULL;
177 nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
178 const char *name, unsigned int len,
179 struct svc_export **exp_ret, struct dentry **dentry_ret)
181 struct svc_export *exp;
182 struct dentry *dparent;
183 struct dentry *dentry;
187 dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
189 /* Obtain dentry and export. */
190 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
194 dparent = fhp->fh_dentry;
195 exp = fhp->fh_export;
198 /* Lookup the name, but don't follow links */
199 if (isdotent(name, len)) {
201 dentry = dget(dparent);
202 else if (dparent != exp->ex_path.dentry)
203 dentry = dget_parent(dparent);
204 else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
205 dentry = dget(dparent); /* .. == . just like at / */
207 /* checking mountpoint crossing is very different when stepping up */
208 host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
214 dentry = lookup_one_len(name, dparent, len);
215 host_err = PTR_ERR(dentry);
219 * check if we have crossed a mount point ...
221 if (nfsd_mountpoint(dentry, exp)) {
222 if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) {
228 *dentry_ret = dentry;
234 return nfserrno(host_err);
238 * Look up one component of a pathname.
239 * N.B. After this call _both_ fhp and resfh need an fh_put
241 * If the lookup would cross a mountpoint, and the mounted filesystem
242 * is exported to the client with NFSEXP_NOHIDE, then the lookup is
243 * accepted as it stands and the mounted directory is
244 * returned. Otherwise the covered directory is returned.
245 * NOTE: this mountpoint crossing is not supported properly by all
246 * clients and is explicitly disallowed for NFSv3
247 * NeilBrown <neilb@cse.unsw.edu.au>
250 nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
251 unsigned int len, struct svc_fh *resfh)
253 struct svc_export *exp;
254 struct dentry *dentry;
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)
277 * Commit metadata changes to stable storage.
280 commit_metadata(struct svc_fh *fhp)
282 struct inode *inode = fhp->fh_dentry->d_inode;
283 const struct export_operations *export_ops = inode->i_sb->s_export_op;
286 if (!EX_ISSYNC(fhp->fh_export))
289 if (export_ops->commit_metadata) {
290 error = export_ops->commit_metadata(inode);
292 struct writeback_control wbc = {
293 .sync_mode = WB_SYNC_ALL,
294 .nr_to_write = 0, /* metadata only */
297 error = sync_inode(inode, &wbc);
304 * Set various file attributes.
305 * N.B. After this call fhp needs an fh_put
308 nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
309 int check_guard, time_t guardtime)
311 struct dentry *dentry;
313 int accmode = NFSD_MAY_SATTR;
319 if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
320 accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
321 if (iap->ia_valid & ATTR_SIZE)
325 err = fh_verify(rqstp, fhp, ftype, accmode);
329 dentry = fhp->fh_dentry;
330 inode = dentry->d_inode;
332 /* Ignore any mode updates on symlinks */
333 if (S_ISLNK(inode->i_mode))
334 iap->ia_valid &= ~ATTR_MODE;
340 * NFSv2 does not differentiate between "set-[ac]time-to-now"
341 * which only requires access, and "set-[ac]time-to-X" which
342 * requires ownership.
343 * So if it looks like it might be "set both to the same time which
344 * is close to now", and if inode_change_ok fails, then we
345 * convert to "set to now" instead of "set to explicit time"
347 * We only call inode_change_ok as the last test as technically
348 * it is not an interface that we should be using. It is only
349 * valid if the filesystem does not define it's own i_op->setattr.
351 #define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
352 #define MAX_TOUCH_TIME_ERROR (30*60)
353 if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET &&
354 iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec) {
358 * Now just make sure time is in the right ballpark.
359 * Solaris, at least, doesn't seem to care what the time
360 * request is. We require it be within 30 minutes of now.
362 time_t delta = iap->ia_atime.tv_sec - get_seconds();
365 if (delta < MAX_TOUCH_TIME_ERROR &&
366 inode_change_ok(inode, iap) != 0) {
368 * Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
369 * This will cause notify_change to set these times
372 iap->ia_valid &= ~BOTH_TIME_SET;
377 * The size case is special.
378 * It changes the file as well as the attributes.
380 if (iap->ia_valid & ATTR_SIZE) {
381 if (iap->ia_size < inode->i_size) {
382 err = nfsd_permission(rqstp, fhp->fh_export, dentry,
383 NFSD_MAY_TRUNC|NFSD_MAY_OWNER_OVERRIDE);
389 * If we are changing the size of the file, then
390 * we need to break all leases.
392 host_err = break_lease(inode, O_WRONLY | O_NONBLOCK);
393 if (host_err == -EWOULDBLOCK)
394 host_err = -ETIMEDOUT;
395 if (host_err) /* ENOMEM or EWOULDBLOCK */
398 host_err = get_write_access(inode);
403 host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
405 put_write_access(inode);
410 /* sanitize the mode change */
411 if (iap->ia_valid & ATTR_MODE) {
412 iap->ia_mode &= S_IALLUGO;
413 iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
416 /* Revoke setuid/setgid on chown */
417 if (!S_ISDIR(inode->i_mode) &&
418 (((iap->ia_valid & ATTR_UID) && iap->ia_uid != inode->i_uid) ||
419 ((iap->ia_valid & ATTR_GID) && iap->ia_gid != inode->i_gid))) {
420 iap->ia_valid |= ATTR_KILL_PRIV;
421 if (iap->ia_valid & ATTR_MODE) {
422 /* we're setting mode too, just clear the s*id bits */
423 iap->ia_mode &= ~S_ISUID;
424 if (iap->ia_mode & S_IXGRP)
425 iap->ia_mode &= ~S_ISGID;
427 /* set ATTR_KILL_* bits and let VFS handle it */
428 iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
432 /* Change the attributes. */
434 iap->ia_valid |= ATTR_CTIME;
436 err = nfserr_notsync;
437 if (!check_guard || guardtime == inode->i_ctime.tv_sec) {
439 host_err = notify_change(dentry, iap);
440 err = nfserrno(host_err);
444 put_write_access(inode);
446 commit_metadata(fhp);
451 err = nfserrno(host_err);
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)
463 buflen = vfs_getxattr(dentry, key, NULL, 0);
467 *buf = kmalloc(buflen, GFP_KERNEL);
471 ret = vfs_getxattr(dentry, key, *buf, buflen);
478 #if defined(CONFIG_NFSD_V4)
480 set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key)
487 buflen = posix_acl_xattr_size(pacl->a_count);
488 buf = kmalloc(buflen, GFP_KERNEL);
493 len = posix_acl_to_xattr(pacl, buf, buflen);
499 error = vfs_setxattr(dentry, key, buf, len, 0);
506 nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
507 struct nfs4_acl *acl)
511 struct dentry *dentry;
513 struct posix_acl *pacl = NULL, *dpacl = NULL;
514 unsigned int flags = 0;
517 error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR);
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)
532 host_error = set_nfsv4_acl_one(dentry, pacl, POSIX_ACL_XATTR_ACCESS);
536 if (S_ISDIR(inode->i_mode))
537 host_error = set_nfsv4_acl_one(dentry, dpacl, POSIX_ACL_XATTR_DEFAULT);
540 posix_acl_release(pacl);
541 posix_acl_release(dpacl);
543 if (host_error == -EOPNOTSUPP)
544 return nfserr_attrnotsupp;
546 return nfserrno(host_error);
549 static struct posix_acl *
550 _get_posix_acl(struct dentry *dentry, char *key)
553 struct posix_acl *pacl = NULL;
556 buflen = nfsd_getxattr(dentry, key, &buf);
560 return ERR_PTR(buflen);
562 pacl = posix_acl_from_xattr(buf, buflen);
568 nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_acl **acl)
570 struct inode *inode = dentry->d_inode;
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);
579 error = PTR_ERR(pacl);
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)
588 else if (IS_ERR(dpacl)) {
589 error = PTR_ERR(dpacl);
593 flags = NFS4_ACL_DIR;
596 *acl = nfs4_acl_posix_to_nfsv4(pacl, dpacl, flags);
598 error = PTR_ERR(*acl);
602 posix_acl_release(pacl);
603 posix_acl_release(dpacl);
607 #endif /* defined(CONFIG_NFS_V4) */
609 #ifdef CONFIG_NFSD_V3
611 * Check server access rights to a file system object
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 },
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 },
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
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 },
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;
661 error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
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;
673 map = nfs3_anyaccess;
677 for (; map->access; map++) {
678 if (map->access & query) {
681 sresult |= map->access;
683 err2 = nfsd_permission(rqstp, export, dentry, map->how);
686 result |= map->access;
689 /* the following error codes just mean the access was not allowed,
690 * rather than an error occurred */
694 /* simply don't "or" in the access bit. */
704 *supported = sresult;
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
719 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
720 int access, struct file **filp)
722 struct dentry *dentry;
724 int flags = O_RDONLY|O_LARGEFILE;
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);
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
746 if (IS_APPEND(inode) && (access & NFSD_MAY_WRITE))
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
753 if (S_ISREG((inode)->i_mode) && mandatory_lock(inode))
760 * Check to see if there are any leases on this file.
761 * This may block while leases are broken.
763 if (!(access & NFSD_MAY_NOT_BREAK_LEASE))
764 host_err = break_lease(inode, O_NONBLOCK | ((access & NFSD_MAY_WRITE) ? O_WRONLY : 0));
765 if (host_err == -EWOULDBLOCK)
766 host_err = -ETIMEDOUT;
767 if (host_err) /* NOMEM or WOULDBLOCK */
770 if (access & NFSD_MAY_WRITE) {
771 if (access & NFSD_MAY_READ)
772 flags = O_RDWR|O_LARGEFILE;
774 flags = O_WRONLY|O_LARGEFILE;
776 *filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
777 flags, current_cred());
779 host_err = PTR_ERR(*filp);
781 host_err = ima_file_check(*filp, access);
783 err = nfserrno(host_err);
785 validate_process_creds();
793 nfsd_close(struct file *filp)
799 * Obtain the readahead parameters for the file
800 * specified by (dev, ino).
803 static inline struct raparms *
804 nfsd_get_raparms(dev_t dev, ino_t ino)
806 struct raparms *ra, **rap, **frap = NULL;
809 struct raparm_hbucket *rab;
811 hash = jhash_2words(dev, ino, 0xfeedbeef) & RAPARM_HASH_MASK;
812 rab = &raparm_hash[hash];
814 spin_lock(&rab->pb_lock);
815 for (rap = &rab->pb_head; (ra = *rap); rap = &ra->p_next) {
816 if (ra->p_ino == ino && ra->p_dev == dev)
819 if (ra->p_count == 0)
822 depth = nfsdstats.ra_size*11/10;
824 spin_unlock(&rab->pb_lock);
834 if (rap != &rab->pb_head) {
836 ra->p_next = rab->pb_head;
840 nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++;
841 spin_unlock(&rab->pb_lock);
846 * Grab and keep cached pages associated with a file in the svc_rqst
847 * so that they can be passed to the network sendmsg/sendpage routines
848 * directly. They will be released after the sending has completed.
851 nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
852 struct splice_desc *sd)
854 struct svc_rqst *rqstp = sd->u.data;
855 struct page **pp = rqstp->rq_respages + rqstp->rq_resused;
856 struct page *page = buf->page;
860 ret = buf->ops->confirm(pipe, buf);
866 if (rqstp->rq_res.page_len == 0) {
871 rqstp->rq_res.page_base = buf->offset;
872 rqstp->rq_res.page_len = size;
873 } else if (page != pp[-1]) {
879 rqstp->rq_res.page_len += size;
881 rqstp->rq_res.page_len += size;
886 static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
887 struct splice_desc *sd)
889 return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
892 static inline int svc_msnfs(struct svc_fh *ffhp)
895 return (ffhp->fh_export->ex_flags & NFSEXP_MSNFS);
902 nfsd_vfs_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
903 loff_t offset, struct kvec *vec, int vlen, unsigned long *count)
912 inode = file->f_path.dentry->d_inode;
914 if (svc_msnfs(fhp) && !lock_may_read(inode, offset, *count))
917 /* Get readahead parameters */
918 ra = nfsd_get_raparms(inode->i_sb->s_dev, inode->i_ino);
921 file->f_ra = ra->p_ra;
923 if (file->f_op->splice_read && rqstp->rq_splice_ok) {
924 struct splice_desc sd = {
931 rqstp->rq_resused = 1;
932 host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor);
936 host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
940 /* Write back readahead params */
942 struct raparm_hbucket *rab = &raparm_hash[ra->p_hindex];
943 spin_lock(&rab->pb_lock);
944 ra->p_ra = file->f_ra;
947 spin_unlock(&rab->pb_lock);
951 nfsdstats.io_read += host_err;
954 fsnotify_access(file->f_path.dentry);
956 err = nfserrno(host_err);
961 static void kill_suid(struct dentry *dentry)
964 ia.ia_valid = ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
966 mutex_lock(&dentry->d_inode->i_mutex);
967 notify_change(dentry, &ia);
968 mutex_unlock(&dentry->d_inode->i_mutex);
972 * Gathered writes: If another process is currently writing to the file,
973 * there's a high chance this is another nfsd (triggered by a bulk write
974 * from a client's biod). Rather than syncing the file with each write
975 * request, we sleep for 10 msec.
977 * I don't know if this roughly approximates C. Juszak's idea of
978 * gathered writes, but it's a nice and simple solution (IMHO), and it
981 * Note: we do this only in the NFSv2 case, since v3 and higher have a
982 * better tool (separate unstable writes and commits) for solving this
985 static int wait_for_concurrent_writes(struct file *file)
987 struct inode *inode = file->f_path.dentry->d_inode;
988 static ino_t last_ino;
989 static dev_t last_dev;
992 if (atomic_read(&inode->i_writecount) > 1
993 || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
994 dprintk("nfsd: write defer %d\n", task_pid_nr(current));
996 dprintk("nfsd: write resume %d\n", task_pid_nr(current));
999 if (inode->i_state & I_DIRTY) {
1000 dprintk("nfsd: write sync %d\n", task_pid_nr(current));
1001 err = vfs_fsync(file, 0);
1003 last_ino = inode->i_ino;
1004 last_dev = inode->i_sb->s_dev;
1009 nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1010 loff_t offset, struct kvec *vec, int vlen,
1011 unsigned long *cnt, int *stablep)
1013 struct svc_export *exp;
1014 struct dentry *dentry;
1015 struct inode *inode;
1019 int stable = *stablep;
1025 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1026 (!lock_may_write(file->f_path.dentry->d_inode, offset, *cnt)))
1030 dentry = file->f_path.dentry;
1031 inode = dentry->d_inode;
1032 exp = fhp->fh_export;
1035 * Request sync writes if
1036 * - the sync export option has been set, or
1037 * - the client requested O_SYNC behavior (NFSv3 feature).
1038 * - The file system doesn't support fsync().
1039 * When NFSv2 gathered writes have been configured for this volume,
1040 * flushing the data to disk is handled separately below.
1042 use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
1044 if (!file->f_op->fsync) {/* COMMIT3 cannot work */
1046 *stablep = 2; /* FILE_SYNC */
1049 if (!EX_ISSYNC(exp))
1051 if (stable && !use_wgather) {
1052 spin_lock(&file->f_lock);
1053 file->f_flags |= O_SYNC;
1054 spin_unlock(&file->f_lock);
1057 /* Write the data. */
1058 oldfs = get_fs(); set_fs(KERNEL_DS);
1059 host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset);
1064 nfsdstats.io_write += host_err;
1065 fsnotify_modify(file->f_path.dentry);
1067 /* clear setuid/setgid flag after write */
1068 if (inode->i_mode & (S_ISUID | S_ISGID))
1071 if (stable && use_wgather)
1072 host_err = wait_for_concurrent_writes(file);
1075 dprintk("nfsd: write complete host_err=%d\n", host_err);
1079 err = nfserrno(host_err);
1085 * Read data from a file. count must contain the requested read count
1086 * on entry. On return, *count contains the number of bytes actually read.
1087 * N.B. After this call fhp needs an fh_put
1090 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1091 loff_t offset, struct kvec *vec, int vlen,
1092 unsigned long *count)
1097 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1098 NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
1101 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1103 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
1106 err = nfsd_vfs_read(rqstp, fhp, file, offset, vec, vlen, count);
1114 * Write data to a file.
1115 * The stable flag requests synchronous writes.
1116 * N.B. After this call fhp needs an fh_put
1119 nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
1120 loff_t offset, struct kvec *vec, int vlen, unsigned long *cnt,
1126 err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
1127 NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE);
1130 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt,
1133 err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file);
1138 err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen,
1146 #ifdef CONFIG_NFSD_V3
1148 * Commit all pending writes to stable storage.
1150 * Note: we only guarantee that data that lies within the range specified
1151 * by the 'offset' and 'count' parameters will be synced.
1153 * Unfortunately we cannot lock the file to make sure we return full WCC
1154 * data to the client, as locking happens lower down in the filesystem.
1157 nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp,
1158 loff_t offset, unsigned long count)
1161 loff_t end = LLONG_MAX;
1162 __be32 err = nfserr_inval;
1167 end = offset + (loff_t)count - 1;
1172 err = nfsd_open(rqstp, fhp, S_IFREG,
1173 NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &file);
1176 if (EX_ISSYNC(fhp->fh_export)) {
1177 int err2 = vfs_fsync_range(file, offset, end, 0);
1179 if (err2 != -EINVAL)
1180 err = nfserrno(err2);
1182 err = nfserr_notsupp;
1189 #endif /* CONFIG_NFSD_V3 */
1192 nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp,
1196 * Mode has already been set earlier in create:
1198 iap->ia_valid &= ~ATTR_MODE;
1200 * Setting uid/gid works only for root. Irix appears to
1201 * send along the gid on create when it tries to implement
1202 * setgid directories via NFS:
1204 if (current_fsuid() != 0)
1205 iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
1207 return nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0);
1211 /* HPUX client sometimes creates a file in mode 000, and sets size to 0.
1212 * setting size to 0 may fail for some specific file systems by the permission
1213 * checking which requires WRITE permission but the mode is 000.
1214 * we ignore the resizing(to 0) on the just new created file, since the size is
1215 * 0 after file created.
1217 * call this only after vfs_create() is called.
1220 nfsd_check_ignore_resizing(struct iattr *iap)
1222 if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
1223 iap->ia_valid &= ~ATTR_SIZE;
1227 * Create a file (regular, directory, device, fifo); UNIX sockets
1228 * not yet implemented.
1229 * If the response fh has been verified, the parent directory should
1230 * already be locked. Note that the parent directory is left locked.
1232 * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1235 nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
1236 char *fname, int flen, struct iattr *iap,
1237 int type, dev_t rdev, struct svc_fh *resfhp)
1239 struct dentry *dentry, *dchild = NULL;
1249 if (isdotent(fname, flen))
1252 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1256 dentry = fhp->fh_dentry;
1257 dirp = dentry->d_inode;
1259 err = nfserr_notdir;
1260 if (!dirp->i_op->lookup)
1263 * Check whether the response file handle has been verified yet.
1264 * If it has, the parent directory should already be locked.
1266 if (!resfhp->fh_dentry) {
1267 /* called from nfsd_proc_mkdir, or possibly nfsd3_proc_create */
1268 fh_lock_nested(fhp, I_MUTEX_PARENT);
1269 dchild = lookup_one_len(fname, dentry, flen);
1270 host_err = PTR_ERR(dchild);
1273 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1277 /* called from nfsd_proc_create */
1278 dchild = dget(resfhp->fh_dentry);
1279 if (!fhp->fh_locked) {
1280 /* not actually possible */
1282 "nfsd_create: parent %s/%s not locked!\n",
1283 dentry->d_parent->d_name.name,
1284 dentry->d_name.name);
1290 * Make sure the child dentry is still negative ...
1293 if (dchild->d_inode) {
1294 dprintk("nfsd_create: dentry %s/%s not negative!\n",
1295 dentry->d_name.name, dchild->d_name.name);
1299 if (!(iap->ia_valid & ATTR_MODE))
1301 iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
1304 if (!S_ISREG(type) && !S_ISDIR(type) && !special_file(type)) {
1305 printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
1310 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1315 * Get the dir op function pointer.
1320 host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1322 nfsd_check_ignore_resizing(iap);
1325 host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
1331 host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
1335 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1339 err = nfsd_create_setattr(rqstp, resfhp, iap);
1342 * nfsd_setattr already committed the child. Transactional filesystems
1343 * had a chance to commit changes for both parent and child
1344 * simultaneously making the following commit_metadata a noop.
1346 err2 = nfserrno(commit_metadata(fhp));
1349 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1351 * Update the file handle to get the new inode info.
1354 err = fh_update(resfhp);
1356 if (dchild && !IS_ERR(dchild))
1361 err = nfserrno(host_err);
1365 #ifdef CONFIG_NFSD_V3
1367 * NFSv3 version of nfsd_create
1370 nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
1371 char *fname, int flen, struct iattr *iap,
1372 struct svc_fh *resfhp, int createmode, u32 *verifier,
1373 int *truncp, int *created)
1375 struct dentry *dentry, *dchild = NULL;
1379 __u32 v_mtime=0, v_atime=0;
1385 if (isdotent(fname, flen))
1387 if (!(iap->ia_valid & ATTR_MODE))
1389 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1393 dentry = fhp->fh_dentry;
1394 dirp = dentry->d_inode;
1396 /* Get all the sanity checks out of the way before
1397 * we lock the parent. */
1398 err = nfserr_notdir;
1399 if (!dirp->i_op->lookup)
1401 fh_lock_nested(fhp, I_MUTEX_PARENT);
1404 * Compose the response file handle.
1406 dchild = lookup_one_len(fname, dentry, flen);
1407 host_err = PTR_ERR(dchild);
1411 err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1415 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1416 /* solaris7 gets confused (bugid 4218508) if these have
1417 * the high bit set, so just clear the high bits. If this is
1418 * ever changed to use different attrs for storing the
1419 * verifier, then do_open_lookup() will also need to be fixed
1422 v_mtime = verifier[0]&0x7fffffff;
1423 v_atime = verifier[1]&0x7fffffff;
1426 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1429 if (dchild->d_inode) {
1432 switch (createmode) {
1433 case NFS3_CREATE_UNCHECKED:
1434 if (! S_ISREG(dchild->d_inode->i_mode))
1437 /* in nfsv4, we need to treat this case a little
1438 * differently. we don't want to truncate the
1439 * file now; this would be wrong if the OPEN
1440 * fails for some other reason. furthermore,
1441 * if the size is nonzero, we should ignore it
1442 * according to spec!
1444 *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size;
1447 iap->ia_valid &= ATTR_SIZE;
1451 case NFS3_CREATE_EXCLUSIVE:
1452 if ( dchild->d_inode->i_mtime.tv_sec == v_mtime
1453 && dchild->d_inode->i_atime.tv_sec == v_atime
1454 && dchild->d_inode->i_size == 0 )
1457 case NFS3_CREATE_GUARDED:
1460 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1464 host_err = vfs_create(dirp, dchild, iap->ia_mode, NULL);
1466 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1472 nfsd_check_ignore_resizing(iap);
1474 if (createmode == NFS3_CREATE_EXCLUSIVE) {
1475 /* Cram the verifier into atime/mtime */
1476 iap->ia_valid = ATTR_MTIME|ATTR_ATIME
1477 | ATTR_MTIME_SET|ATTR_ATIME_SET;
1478 /* XXX someone who knows this better please fix it for nsec */
1479 iap->ia_mtime.tv_sec = v_mtime;
1480 iap->ia_atime.tv_sec = v_atime;
1481 iap->ia_mtime.tv_nsec = 0;
1482 iap->ia_atime.tv_nsec = 0;
1486 err = nfsd_create_setattr(rqstp, resfhp, iap);
1489 * nfsd_setattr already committed the child (and possibly also the parent).
1492 err = nfserrno(commit_metadata(fhp));
1494 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1496 * Update the filehandle to get the new inode info.
1499 err = fh_update(resfhp);
1503 if (dchild && !IS_ERR(dchild))
1508 err = nfserrno(host_err);
1511 #endif /* CONFIG_NFSD_V3 */
1514 * Read a symlink. On entry, *lenp must contain the maximum path length that
1515 * fits into the buffer. On return, it contains the true length.
1516 * N.B. After this call fhp needs an fh_put
1519 nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
1521 struct dentry *dentry;
1522 struct inode *inode;
1527 err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
1531 dentry = fhp->fh_dentry;
1532 inode = dentry->d_inode;
1535 if (!inode->i_op->readlink)
1538 touch_atime(fhp->fh_export->ex_path.mnt, dentry);
1539 /* N.B. Why does this call need a get_fs()??
1540 * Remove the set_fs and watch the fireworks:-) --okir
1543 oldfs = get_fs(); set_fs(KERNEL_DS);
1544 host_err = inode->i_op->readlink(dentry, buf, *lenp);
1555 err = nfserrno(host_err);
1560 * Create a symlink and look up its inode
1561 * N.B. After this call _both_ fhp and resfhp need an fh_put
1564 nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
1565 char *fname, int flen,
1566 char *path, int plen,
1567 struct svc_fh *resfhp,
1570 struct dentry *dentry, *dnew;
1578 if (isdotent(fname, flen))
1581 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
1585 dentry = fhp->fh_dentry;
1586 dnew = lookup_one_len(fname, dentry, flen);
1587 host_err = PTR_ERR(dnew);
1591 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1595 if (unlikely(path[plen] != 0)) {
1596 char *path_alloced = kmalloc(plen+1, GFP_KERNEL);
1597 if (path_alloced == NULL)
1600 strncpy(path_alloced, path, plen);
1601 path_alloced[plen] = 0;
1602 host_err = vfs_symlink(dentry->d_inode, dnew, path_alloced);
1603 kfree(path_alloced);
1606 host_err = vfs_symlink(dentry->d_inode, dnew, path);
1607 err = nfserrno(host_err);
1609 err = nfserrno(commit_metadata(fhp));
1612 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1614 cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
1616 if (err==0) err = cerr;
1621 err = nfserrno(host_err);
1627 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1630 nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
1631 char *name, int len, struct svc_fh *tfhp)
1633 struct dentry *ddir, *dnew, *dold;
1634 struct inode *dirp, *dest;
1638 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
1641 err = fh_verify(rqstp, tfhp, -S_IFDIR, NFSD_MAY_NOP);
1649 if (isdotent(name, len))
1652 fh_lock_nested(ffhp, I_MUTEX_PARENT);
1653 ddir = ffhp->fh_dentry;
1654 dirp = ddir->d_inode;
1656 dnew = lookup_one_len(name, ddir, len);
1657 host_err = PTR_ERR(dnew);
1661 dold = tfhp->fh_dentry;
1662 dest = dold->d_inode;
1664 host_err = mnt_want_write(tfhp->fh_export->ex_path.mnt);
1666 err = nfserrno(host_err);
1669 host_err = vfs_link(dold, dirp, dnew);
1671 err = nfserrno(commit_metadata(ffhp));
1673 err = nfserrno(commit_metadata(tfhp));
1675 if (host_err == -EXDEV && rqstp->rq_vers == 2)
1678 err = nfserrno(host_err);
1680 mnt_drop_write(tfhp->fh_export->ex_path.mnt);
1689 err = nfserrno(host_err);
1695 * N.B. After this call _both_ ffhp and tfhp need an fh_put
1698 nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
1699 struct svc_fh *tfhp, char *tname, int tlen)
1701 struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
1702 struct inode *fdir, *tdir;
1706 err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
1709 err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
1713 fdentry = ffhp->fh_dentry;
1714 fdir = fdentry->d_inode;
1716 tdentry = tfhp->fh_dentry;
1717 tdir = tdentry->d_inode;
1719 err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
1720 if (ffhp->fh_export != tfhp->fh_export)
1724 if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
1727 /* cannot use fh_lock as we need deadlock protective ordering
1728 * so do it by hand */
1729 trap = lock_rename(tdentry, fdentry);
1730 ffhp->fh_locked = tfhp->fh_locked = 1;
1734 odentry = lookup_one_len(fname, fdentry, flen);
1735 host_err = PTR_ERR(odentry);
1736 if (IS_ERR(odentry))
1740 if (!odentry->d_inode)
1743 if (odentry == trap)
1746 ndentry = lookup_one_len(tname, tdentry, tlen);
1747 host_err = PTR_ERR(ndentry);
1748 if (IS_ERR(ndentry))
1750 host_err = -ENOTEMPTY;
1751 if (ndentry == trap)
1754 if (svc_msnfs(ffhp) &&
1755 ((atomic_read(&odentry->d_count) > 1)
1756 || (atomic_read(&ndentry->d_count) > 1))) {
1762 if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
1764 host_err = mnt_want_write(ffhp->fh_export->ex_path.mnt);
1768 host_err = vfs_rename(fdir, odentry, tdir, ndentry);
1770 host_err = commit_metadata(tfhp);
1772 host_err = commit_metadata(ffhp);
1775 mnt_drop_write(ffhp->fh_export->ex_path.mnt);
1782 err = nfserrno(host_err);
1784 /* we cannot reply on fh_unlock on the two filehandles,
1785 * as that would do the wrong thing if the two directories
1786 * were the same, so again we do it by hand
1788 fill_post_wcc(ffhp);
1789 fill_post_wcc(tfhp);
1790 unlock_rename(tdentry, fdentry);
1791 ffhp->fh_locked = tfhp->fh_locked = 0;
1798 * Unlink a file or directory
1799 * N.B. After this call fhp needs an fh_put
1802 nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
1803 char *fname, int flen)
1805 struct dentry *dentry, *rdentry;
1811 if (!flen || isdotent(fname, flen))
1813 err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
1817 fh_lock_nested(fhp, I_MUTEX_PARENT);
1818 dentry = fhp->fh_dentry;
1819 dirp = dentry->d_inode;
1821 rdentry = lookup_one_len(fname, dentry, flen);
1822 host_err = PTR_ERR(rdentry);
1823 if (IS_ERR(rdentry))
1826 if (!rdentry->d_inode) {
1833 type = rdentry->d_inode->i_mode & S_IFMT;
1835 host_err = mnt_want_write(fhp->fh_export->ex_path.mnt);
1839 if (type != S_IFDIR) { /* It's UNLINK */
1841 if ((fhp->fh_export->ex_flags & NFSEXP_MSNFS) &&
1842 (atomic_read(&rdentry->d_count) > 1)) {
1846 host_err = vfs_unlink(dirp, rdentry);
1847 } else { /* It's RMDIR */
1848 host_err = vfs_rmdir(dirp, rdentry);
1854 host_err = commit_metadata(fhp);
1856 mnt_drop_write(fhp->fh_export->ex_path.mnt);
1858 err = nfserrno(host_err);
1864 * We do this buffering because we must not call back into the file
1865 * system's ->lookup() method from the filldir callback. That may well
1866 * deadlock a number of file systems.
1868 * This is based heavily on the implementation of same in XFS.
1870 struct buffered_dirent {
1874 unsigned int d_type;
1878 struct readdir_data {
1884 static int nfsd_buffered_filldir(void *__buf, const char *name, int namlen,
1885 loff_t offset, u64 ino, unsigned int d_type)
1887 struct readdir_data *buf = __buf;
1888 struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
1889 unsigned int reclen;
1891 reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
1892 if (buf->used + reclen > PAGE_SIZE) {
1897 de->namlen = namlen;
1898 de->offset = offset;
1900 de->d_type = d_type;
1901 memcpy(de->name, name, namlen);
1902 buf->used += reclen;
1907 static __be32 nfsd_buffered_readdir(struct file *file, filldir_t func,
1908 struct readdir_cd *cdp, loff_t *offsetp)
1910 struct readdir_data buf;
1911 struct buffered_dirent *de;
1916 buf.dirent = (void *)__get_free_page(GFP_KERNEL);
1918 return nfserrno(-ENOMEM);
1923 struct inode *dir_inode = file->f_path.dentry->d_inode;
1924 unsigned int reclen;
1926 cdp->err = nfserr_eof; /* will be cleared on successful read */
1930 host_err = vfs_readdir(file, nfsd_buffered_filldir, &buf);
1943 * Various filldir functions may end up calling back into
1944 * lookup_one_len() and the file system's ->lookup() method.
1945 * These expect i_mutex to be held, as it would within readdir.
1947 host_err = mutex_lock_killable(&dir_inode->i_mutex);
1951 de = (struct buffered_dirent *)buf.dirent;
1953 offset = de->offset;
1955 if (func(cdp, de->name, de->namlen, de->offset,
1956 de->ino, de->d_type))
1959 if (cdp->err != nfs_ok)
1962 reclen = ALIGN(sizeof(*de) + de->namlen,
1965 de = (struct buffered_dirent *)((char *)de + reclen);
1967 mutex_unlock(&dir_inode->i_mutex);
1968 if (size > 0) /* We bailed out early */
1971 offset = vfs_llseek(file, 0, SEEK_CUR);
1974 free_page((unsigned long)(buf.dirent));
1977 return nfserrno(host_err);
1984 * Read entries from a directory.
1985 * The NFSv3/4 verifier we ignore for now.
1988 nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
1989 struct readdir_cd *cdp, filldir_t func)
1993 loff_t offset = *offsetp;
1995 err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file);
1999 offset = vfs_llseek(file, offset, 0);
2001 err = nfserrno((int)offset);
2005 err = nfsd_buffered_readdir(file, func, cdp, offsetp);
2007 if (err == nfserr_eof || err == nfserr_toosmall)
2008 err = nfs_ok; /* can still be found in ->err */
2016 * Get file system stats
2017 * N.B. After this call fhp needs an fh_put
2020 nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
2022 struct path path = {
2023 .mnt = fhp->fh_export->ex_path.mnt,
2024 .dentry = fhp->fh_dentry,
2028 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
2029 if (!err && vfs_statfs(&path, stat))
2034 static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp)
2036 return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY;
2040 * Check for a user's access permissions to this inode.
2043 nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
2044 struct dentry *dentry, int acc)
2046 struct inode *inode = dentry->d_inode;
2050 if (acc == NFSD_MAY_NOP)
2053 dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
2055 (acc & NFSD_MAY_READ)? " read" : "",
2056 (acc & NFSD_MAY_WRITE)? " write" : "",
2057 (acc & NFSD_MAY_EXEC)? " exec" : "",
2058 (acc & NFSD_MAY_SATTR)? " sattr" : "",
2059 (acc & NFSD_MAY_TRUNC)? " trunc" : "",
2060 (acc & NFSD_MAY_LOCK)? " lock" : "",
2061 (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
2063 IS_IMMUTABLE(inode)? " immut" : "",
2064 IS_APPEND(inode)? " append" : "",
2065 __mnt_is_readonly(exp->ex_path.mnt)? " ro" : "");
2066 dprintk(" owner %d/%d user %d/%d\n",
2067 inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
2070 /* Normally we reject any write/sattr etc access on a read-only file
2071 * system. But if it is IRIX doing check on write-access for a
2072 * device special file, we ignore rofs.
2074 if (!(acc & NFSD_MAY_LOCAL_ACCESS))
2075 if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
2076 if (exp_rdonly(rqstp, exp) ||
2077 __mnt_is_readonly(exp->ex_path.mnt))
2079 if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode))
2082 if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
2085 if (acc & NFSD_MAY_LOCK) {
2086 /* If we cannot rely on authentication in NLM requests,
2087 * just allow locks, otherwise require read permission, or
2090 if (exp->ex_flags & NFSEXP_NOAUTHNLM)
2093 acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
2096 * The file owner always gets access permission for accesses that
2097 * would normally be checked at open time. This is to make
2098 * file access work even when the client has done a fchmod(fd, 0).
2100 * However, `cp foo bar' should fail nevertheless when bar is
2101 * readonly. A sensible way to do this might be to reject all
2102 * attempts to truncate a read-only file, because a creat() call
2103 * always implies file truncation.
2104 * ... but this isn't really fair. A process may reasonably call
2105 * ftruncate on an open file descriptor on a file with perm 000.
2106 * We must trust the client to do permission checking - using "ACCESS"
2109 if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
2110 inode->i_uid == current_fsuid())
2113 /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
2114 err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
2116 /* Allow read access to binaries even when mode 111 */
2117 if (err == -EACCES && S_ISREG(inode->i_mode) &&
2118 acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE))
2119 err = inode_permission(inode, MAY_EXEC);
2123 /* Do integrity (permission) checking now, but defer incrementing
2124 * IMA counts to the actual file open.
2126 path.mnt = exp->ex_path.mnt;
2127 path.dentry = dentry;
2129 return err? nfserrno(err) : 0;
2133 nfsd_racache_shutdown(void)
2135 struct raparms *raparm, *last_raparm;
2138 dprintk("nfsd: freeing readahead buffers.\n");
2140 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2141 raparm = raparm_hash[i].pb_head;
2143 last_raparm = raparm;
2144 raparm = raparm->p_next;
2147 raparm_hash[i].pb_head = NULL;
2151 * Initialize readahead param cache
2154 nfsd_racache_init(int cache_size)
2159 struct raparms **raparm = NULL;
2162 if (raparm_hash[0].pb_head)
2164 nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE);
2167 cache_size = nperbucket * RAPARM_HASH_SIZE;
2169 dprintk("nfsd: allocating %d readahead buffers.\n", cache_size);
2171 for (i = 0; i < RAPARM_HASH_SIZE; i++) {
2172 spin_lock_init(&raparm_hash[i].pb_lock);
2174 raparm = &raparm_hash[i].pb_head;
2175 for (j = 0; j < nperbucket; j++) {
2176 *raparm = kzalloc(sizeof(struct raparms), GFP_KERNEL);
2179 raparm = &(*raparm)->p_next;
2184 nfsdstats.ra_size = cache_size;
2188 dprintk("nfsd: kmalloc failed, freeing readahead buffers\n");
2189 nfsd_racache_shutdown();
2193 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
2195 nfsd_get_posix_acl(struct svc_fh *fhp, int type)
2197 struct inode *inode = fhp->fh_dentry->d_inode;
2201 struct posix_acl *acl;
2203 if (!IS_POSIXACL(inode))
2204 return ERR_PTR(-EOPNOTSUPP);
2207 case ACL_TYPE_ACCESS:
2208 name = POSIX_ACL_XATTR_ACCESS;
2210 case ACL_TYPE_DEFAULT:
2211 name = POSIX_ACL_XATTR_DEFAULT;
2214 return ERR_PTR(-EOPNOTSUPP);
2217 size = nfsd_getxattr(fhp->fh_dentry, name, &value);
2219 return ERR_PTR(size);
2221 acl = posix_acl_from_xattr(value, size);
2227 nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
2229 struct inode *inode = fhp->fh_dentry->d_inode;
2235 if (!IS_POSIXACL(inode) ||
2236 !inode->i_op->setxattr || !inode->i_op->removexattr)
2239 case ACL_TYPE_ACCESS:
2240 name = POSIX_ACL_XATTR_ACCESS;
2242 case ACL_TYPE_DEFAULT:
2243 name = POSIX_ACL_XATTR_DEFAULT;
2249 if (acl && acl->a_count) {
2250 size = posix_acl_xattr_size(acl->a_count);
2251 value = kmalloc(size, GFP_KERNEL);
2254 error = posix_acl_to_xattr(acl, value, size);
2261 error = mnt_want_write(fhp->fh_export->ex_path.mnt);
2265 error = vfs_setxattr(fhp->fh_dentry, name, value, size, 0);
2267 if (!S_ISDIR(inode->i_mode) && type == ACL_TYPE_DEFAULT)
2270 error = vfs_removexattr(fhp->fh_dentry, name);
2271 if (error == -ENODATA)
2275 mnt_drop_write(fhp->fh_export->ex_path.mnt);
2281 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */