1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
21da177e4SLinus Torvalds /*
31da177e4SLinus Torvalds * File operations used by nfsd. Some of these have been ripped from
41da177e4SLinus Torvalds * other parts of the kernel because they weren't exported, others
51da177e4SLinus Torvalds * are partial duplicates with added or changed functionality.
61da177e4SLinus Torvalds *
71da177e4SLinus Torvalds * Note that several functions dget() the dentry upon which they want
81da177e4SLinus Torvalds * to act, most notably those that create directory entries. Response
91da177e4SLinus Torvalds * dentry's are dput()'d if necessary in the release callback.
101da177e4SLinus Torvalds * So if you notice code paths that apparently fail to dput() the
111da177e4SLinus Torvalds * dentry, don't worry--they have been taken care of.
121da177e4SLinus Torvalds *
131da177e4SLinus Torvalds * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de>
141da177e4SLinus Torvalds * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp>
151da177e4SLinus Torvalds */
161da177e4SLinus Torvalds
171da177e4SLinus Torvalds #include <linux/fs.h>
181da177e4SLinus Torvalds #include <linux/file.h>
19d6b29d7cSJens Axboe #include <linux/splice.h>
2095d871f0SAnna Schumaker #include <linux/falloc.h>
211da177e4SLinus Torvalds #include <linux/fcntl.h>
221da177e4SLinus Torvalds #include <linux/namei.h>
231da177e4SLinus Torvalds #include <linux/delay.h>
240eeca283SRobert Love #include <linux/fsnotify.h>
251da177e4SLinus Torvalds #include <linux/posix_acl_xattr.h>
261da177e4SLinus Torvalds #include <linux/xattr.h>
279a74af21SBoaz Harrosh #include <linux/jhash.h>
28cbcc268bSMatthew Wilcox (Oracle) #include <linux/pagemap.h>
295a0e3ad6STejun Heo #include <linux/slab.h>
307c0f6ba6SLinus Torvalds #include <linux/uaccess.h>
31f501912aSBen Myers #include <linux/exportfs.h>
32f501912aSBen Myers #include <linux/writeback.h>
3318032ca0SDavid Quigley #include <linux/security.h>
349a74af21SBoaz Harrosh
359a74af21SBoaz Harrosh #include "xdr3.h"
369a74af21SBoaz Harrosh
375be196e5SChristoph Hellwig #ifdef CONFIG_NFSD_V4
38ffa0160aSChristoph Hellwig #include "../internal.h"
392ca72e17SJ. Bruce Fields #include "acl.h"
402ca72e17SJ. Bruce Fields #include "idmap.h"
41a2f4c3faSTrond Myklebust #include "xdr4.h"
421da177e4SLinus Torvalds #endif /* CONFIG_NFSD_V4 */
431da177e4SLinus Torvalds
449a74af21SBoaz Harrosh #include "nfsd.h"
459a74af21SBoaz Harrosh #include "vfs.h"
46b4935239SJeff Layton #include "filecache.h"
476e8b50d1SJeff Layton #include "trace.h"
481da177e4SLinus Torvalds
491da177e4SLinus Torvalds #define NFSDDBG_FACILITY NFSDDBG_FILEOP
501da177e4SLinus Torvalds
51cb12fae1SJeff Layton /**
52cb12fae1SJeff Layton * nfserrno - Map Linux errnos to NFS errnos
53cb12fae1SJeff Layton * @errno: POSIX(-ish) error code to be mapped
54cb12fae1SJeff Layton *
55cb12fae1SJeff Layton * Returns the appropriate (net-endian) nfserr_* (or nfs_ok if errno is 0). If
56cb12fae1SJeff Layton * it's an error we don't expect, log it once and return nfserr_io.
57cb12fae1SJeff Layton */
58cb12fae1SJeff Layton __be32
nfserrno(int errno)59cb12fae1SJeff Layton nfserrno (int errno)
60cb12fae1SJeff Layton {
61cb12fae1SJeff Layton static struct {
62cb12fae1SJeff Layton __be32 nfserr;
63cb12fae1SJeff Layton int syserr;
64cb12fae1SJeff Layton } nfs_errtbl[] = {
65cb12fae1SJeff Layton { nfs_ok, 0 },
66cb12fae1SJeff Layton { nfserr_perm, -EPERM },
67cb12fae1SJeff Layton { nfserr_noent, -ENOENT },
68cb12fae1SJeff Layton { nfserr_io, -EIO },
69cb12fae1SJeff Layton { nfserr_nxio, -ENXIO },
70cb12fae1SJeff Layton { nfserr_fbig, -E2BIG },
71cb12fae1SJeff Layton { nfserr_stale, -EBADF },
72cb12fae1SJeff Layton { nfserr_acces, -EACCES },
73cb12fae1SJeff Layton { nfserr_exist, -EEXIST },
74cb12fae1SJeff Layton { nfserr_xdev, -EXDEV },
75cb12fae1SJeff Layton { nfserr_mlink, -EMLINK },
76cb12fae1SJeff Layton { nfserr_nodev, -ENODEV },
77cb12fae1SJeff Layton { nfserr_notdir, -ENOTDIR },
78cb12fae1SJeff Layton { nfserr_isdir, -EISDIR },
79cb12fae1SJeff Layton { nfserr_inval, -EINVAL },
80cb12fae1SJeff Layton { nfserr_fbig, -EFBIG },
81cb12fae1SJeff Layton { nfserr_nospc, -ENOSPC },
82cb12fae1SJeff Layton { nfserr_rofs, -EROFS },
83cb12fae1SJeff Layton { nfserr_mlink, -EMLINK },
84cb12fae1SJeff Layton { nfserr_nametoolong, -ENAMETOOLONG },
85cb12fae1SJeff Layton { nfserr_notempty, -ENOTEMPTY },
86cb12fae1SJeff Layton { nfserr_dquot, -EDQUOT },
87cb12fae1SJeff Layton { nfserr_stale, -ESTALE },
88cb12fae1SJeff Layton { nfserr_jukebox, -ETIMEDOUT },
89cb12fae1SJeff Layton { nfserr_jukebox, -ERESTARTSYS },
90cb12fae1SJeff Layton { nfserr_jukebox, -EAGAIN },
91cb12fae1SJeff Layton { nfserr_jukebox, -EWOULDBLOCK },
92cb12fae1SJeff Layton { nfserr_jukebox, -ENOMEM },
93cb12fae1SJeff Layton { nfserr_io, -ETXTBSY },
94cb12fae1SJeff Layton { nfserr_notsupp, -EOPNOTSUPP },
95cb12fae1SJeff Layton { nfserr_toosmall, -ETOOSMALL },
96cb12fae1SJeff Layton { nfserr_serverfault, -ESERVERFAULT },
97cb12fae1SJeff Layton { nfserr_serverfault, -ENFILE },
98cb12fae1SJeff Layton { nfserr_io, -EREMOTEIO },
99cb12fae1SJeff Layton { nfserr_stale, -EOPENSTALE },
100cb12fae1SJeff Layton { nfserr_io, -EUCLEAN },
101cb12fae1SJeff Layton { nfserr_perm, -ENOKEY },
102cb12fae1SJeff Layton { nfserr_no_grace, -ENOGRACE},
103cb12fae1SJeff Layton };
104cb12fae1SJeff Layton int i;
105cb12fae1SJeff Layton
106cb12fae1SJeff Layton for (i = 0; i < ARRAY_SIZE(nfs_errtbl); i++) {
107cb12fae1SJeff Layton if (nfs_errtbl[i].syserr == errno)
108cb12fae1SJeff Layton return nfs_errtbl[i].nfserr;
109cb12fae1SJeff Layton }
110cb12fae1SJeff Layton WARN_ONCE(1, "nfsd: non-standard errno: %d\n", errno);
111cb12fae1SJeff Layton return nfserr_io;
112cb12fae1SJeff Layton }
113cb12fae1SJeff Layton
1141da177e4SLinus Torvalds /*
1151da177e4SLinus Torvalds * Called from nfsd_lookup and encode_dirent. Check if we have crossed
1161da177e4SLinus Torvalds * a mount point.
117e0bb89efSJ.Bruce Fields * Returns -EAGAIN or -ETIMEDOUT leaving *dpp and *expp unchanged,
1181da177e4SLinus Torvalds * or nfs_ok having possibly changed *dpp and *expp
1191da177e4SLinus Torvalds */
1201da177e4SLinus Torvalds int
nfsd_cross_mnt(struct svc_rqst * rqstp,struct dentry ** dpp,struct svc_export ** expp)1211da177e4SLinus Torvalds nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp,
1221da177e4SLinus Torvalds struct svc_export **expp)
1231da177e4SLinus Torvalds {
1241da177e4SLinus Torvalds struct svc_export *exp = *expp, *exp2 = NULL;
1251da177e4SLinus Torvalds struct dentry *dentry = *dpp;
12691c9fa8fSAl Viro struct path path = {.mnt = mntget(exp->ex_path.mnt),
12791c9fa8fSAl Viro .dentry = dget(dentry)};
128e1f19857SRichard Weinberger unsigned int follow_flags = 0;
1296264d69dSAl Viro int err = 0;
1301da177e4SLinus Torvalds
131e1f19857SRichard Weinberger if (exp->ex_flags & NFSEXP_CROSSMOUNT)
132e1f19857SRichard Weinberger follow_flags = LOOKUP_AUTOMOUNT;
133e1f19857SRichard Weinberger
134e1f19857SRichard Weinberger err = follow_down(&path, follow_flags);
135cc53ce53SDavid Howells if (err < 0)
136cc53ce53SDavid Howells goto out;
13799bbf6ecSNeilBrown if (path.mnt == exp->ex_path.mnt && path.dentry == dentry &&
13899bbf6ecSNeilBrown nfsd_mountpoint(dentry, exp) == 2) {
13999bbf6ecSNeilBrown /* This is only a mountpoint in some other namespace */
14099bbf6ecSNeilBrown path_put(&path);
14199bbf6ecSNeilBrown goto out;
14299bbf6ecSNeilBrown }
1431da177e4SLinus Torvalds
14491c9fa8fSAl Viro exp2 = rqst_exp_get_by_name(rqstp, &path);
1451da177e4SLinus Torvalds if (IS_ERR(exp2)) {
1461da177e4SLinus Torvalds err = PTR_ERR(exp2);
1473b6cee7bSJ. Bruce Fields /*
1483b6cee7bSJ. Bruce Fields * We normally allow NFS clients to continue
1493b6cee7bSJ. Bruce Fields * "underneath" a mountpoint that is not exported.
1503b6cee7bSJ. Bruce Fields * The exception is V4ROOT, where no traversal is ever
1513b6cee7bSJ. Bruce Fields * allowed without an explicit export of the new
1523b6cee7bSJ. Bruce Fields * directory.
1533b6cee7bSJ. Bruce Fields */
1543b6cee7bSJ. Bruce Fields if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT))
1553b6cee7bSJ. Bruce Fields err = 0;
15691c9fa8fSAl Viro path_put(&path);
1571da177e4SLinus Torvalds goto out;
1581da177e4SLinus Torvalds }
1593c394ddaSSteve Dickson if (nfsd_v4client(rqstp) ||
1603c394ddaSSteve Dickson (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) {
1611da177e4SLinus Torvalds /* successfully crossed mount point */
1621644ccc8SAl Viro /*
16391c9fa8fSAl Viro * This is subtle: path.dentry is *not* on path.mnt
16491c9fa8fSAl Viro * at this point. The only reason we are safe is that
16591c9fa8fSAl Viro * original mnt is pinned down by exp, so we should
16691c9fa8fSAl Viro * put path *before* putting exp
1671644ccc8SAl Viro */
16891c9fa8fSAl Viro *dpp = path.dentry;
16991c9fa8fSAl Viro path.dentry = dentry;
1701644ccc8SAl Viro *expp = exp2;
17191c9fa8fSAl Viro exp2 = exp;
1721da177e4SLinus Torvalds }
17391c9fa8fSAl Viro path_put(&path);
17491c9fa8fSAl Viro exp_put(exp2);
1751da177e4SLinus Torvalds out:
1761da177e4SLinus Torvalds return err;
1771da177e4SLinus Torvalds }
1781da177e4SLinus Torvalds
follow_to_parent(struct path * path)179289ede45SJ. Bruce Fields static void follow_to_parent(struct path *path)
180289ede45SJ. Bruce Fields {
181289ede45SJ. Bruce Fields struct dentry *dp;
182289ede45SJ. Bruce Fields
183289ede45SJ. Bruce Fields while (path->dentry == path->mnt->mnt_root && follow_up(path))
184289ede45SJ. Bruce Fields ;
185289ede45SJ. Bruce Fields dp = dget_parent(path->dentry);
186289ede45SJ. Bruce Fields dput(path->dentry);
187289ede45SJ. Bruce Fields path->dentry = dp;
188289ede45SJ. Bruce Fields }
189289ede45SJ. Bruce Fields
nfsd_lookup_parent(struct svc_rqst * rqstp,struct dentry * dparent,struct svc_export ** exp,struct dentry ** dentryp)190289ede45SJ. Bruce Fields static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp)
191289ede45SJ. Bruce Fields {
192289ede45SJ. Bruce Fields struct svc_export *exp2;
193289ede45SJ. Bruce Fields struct path path = {.mnt = mntget((*exp)->ex_path.mnt),
194289ede45SJ. Bruce Fields .dentry = dget(dparent)};
195289ede45SJ. Bruce Fields
196289ede45SJ. Bruce Fields follow_to_parent(&path);
197289ede45SJ. Bruce Fields
198289ede45SJ. Bruce Fields exp2 = rqst_exp_parent(rqstp, &path);
199289ede45SJ. Bruce Fields if (PTR_ERR(exp2) == -ENOENT) {
200289ede45SJ. Bruce Fields *dentryp = dget(dparent);
201289ede45SJ. Bruce Fields } else if (IS_ERR(exp2)) {
202289ede45SJ. Bruce Fields path_put(&path);
203289ede45SJ. Bruce Fields return PTR_ERR(exp2);
204289ede45SJ. Bruce Fields } else {
205289ede45SJ. Bruce Fields *dentryp = dget(path.dentry);
206289ede45SJ. Bruce Fields exp_put(*exp);
207289ede45SJ. Bruce Fields *exp = exp2;
208289ede45SJ. Bruce Fields }
209289ede45SJ. Bruce Fields path_put(&path);
210289ede45SJ. Bruce Fields return 0;
211289ede45SJ. Bruce Fields }
212289ede45SJ. Bruce Fields
21382ead7feSJ. Bruce Fields /*
21482ead7feSJ. Bruce Fields * For nfsd purposes, we treat V4ROOT exports as though there was an
21582ead7feSJ. Bruce Fields * export at *every* directory.
21699bbf6ecSNeilBrown * We return:
21799bbf6ecSNeilBrown * '1' if this dentry *must* be an export point,
21899bbf6ecSNeilBrown * '2' if it might be, if there is really a mount here, and
21999bbf6ecSNeilBrown * '0' if there is no chance of an export point here.
22082ead7feSJ. Bruce Fields */
nfsd_mountpoint(struct dentry * dentry,struct svc_export * exp)2213227fa41SJ. Bruce Fields int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
22282ead7feSJ. Bruce Fields {
22399bbf6ecSNeilBrown if (!d_inode(dentry))
22499bbf6ecSNeilBrown return 0;
22599bbf6ecSNeilBrown if (exp->ex_flags & NFSEXP_V4ROOT)
22682ead7feSJ. Bruce Fields return 1;
22711fcee02STrond Myklebust if (nfsd4_is_junction(dentry))
22811fcee02STrond Myklebust return 1;
22950f5fdaeSRichard Weinberger if (d_managed(dentry))
23099bbf6ecSNeilBrown /*
23199bbf6ecSNeilBrown * Might only be a mountpoint in a different namespace,
23299bbf6ecSNeilBrown * but we need to check.
23399bbf6ecSNeilBrown */
23499bbf6ecSNeilBrown return 2;
23582ead7feSJ. Bruce Fields return 0;
23682ead7feSJ. Bruce Fields }
23782ead7feSJ. Bruce Fields
2386264d69dSAl Viro __be32
nfsd_lookup_dentry(struct svc_rqst * rqstp,struct svc_fh * fhp,const char * name,unsigned int len,struct svc_export ** exp_ret,struct dentry ** dentry_ret)2396c0a654dSJ. Bruce Fields nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
2405a022fc8SChuck Lever const char *name, unsigned int len,
2416c0a654dSJ. Bruce Fields struct svc_export **exp_ret, struct dentry **dentry_ret)
2421da177e4SLinus Torvalds {
2431da177e4SLinus Torvalds struct svc_export *exp;
2441da177e4SLinus Torvalds struct dentry *dparent;
2451da177e4SLinus Torvalds struct dentry *dentry;
2466264d69dSAl Viro int host_err;
2471da177e4SLinus Torvalds
2481da177e4SLinus Torvalds dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name);
2491da177e4SLinus Torvalds
2501da177e4SLinus Torvalds dparent = fhp->fh_dentry;
251bf18f163SKinglong Mee exp = exp_get(fhp->fh_export);
2521da177e4SLinus Torvalds
2531da177e4SLinus Torvalds /* Lookup the name, but don't follow links */
2541da177e4SLinus Torvalds if (isdotent(name, len)) {
2551da177e4SLinus Torvalds if (len==1)
2561da177e4SLinus Torvalds dentry = dget(dparent);
25754775491SJan Blunck else if (dparent != exp->ex_path.dentry)
2581da177e4SLinus Torvalds dentry = dget_parent(dparent);
259fed83811SJ. Bruce Fields else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp))
2601da177e4SLinus Torvalds dentry = dget(dparent); /* .. == . just like at / */
2611da177e4SLinus Torvalds else {
2621da177e4SLinus Torvalds /* checking mountpoint crossing is very different when stepping up */
263289ede45SJ. Bruce Fields host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry);
264289ede45SJ. Bruce Fields if (host_err)
2651da177e4SLinus Torvalds goto out_nfserr;
2661da177e4SLinus Torvalds }
2671da177e4SLinus Torvalds } else {
26819d008b4SNeilBrown dentry = lookup_one_len_unlocked(name, dparent, len);
2696264d69dSAl Viro host_err = PTR_ERR(dentry);
2701da177e4SLinus Torvalds if (IS_ERR(dentry))
2711da177e4SLinus Torvalds goto out_nfserr;
27282ead7feSJ. Bruce Fields if (nfsd_mountpoint(dentry, exp)) {
27319d008b4SNeilBrown host_err = nfsd_cross_mnt(rqstp, &dentry, &exp);
27419d008b4SNeilBrown if (host_err) {
2751da177e4SLinus Torvalds dput(dentry);
2761da177e4SLinus Torvalds goto out_nfserr;
2771da177e4SLinus Torvalds }
2781da177e4SLinus Torvalds }
2791da177e4SLinus Torvalds }
2806c0a654dSJ. Bruce Fields *dentry_ret = dentry;
2816c0a654dSJ. Bruce Fields *exp_ret = exp;
2826c0a654dSJ. Bruce Fields return 0;
2836c0a654dSJ. Bruce Fields
2846c0a654dSJ. Bruce Fields out_nfserr:
2856c0a654dSJ. Bruce Fields exp_put(exp);
2866c0a654dSJ. Bruce Fields return nfserrno(host_err);
2876c0a654dSJ. Bruce Fields }
2886c0a654dSJ. Bruce Fields
28919d008b4SNeilBrown /**
29019d008b4SNeilBrown * nfsd_lookup - look up a single path component for nfsd
29119d008b4SNeilBrown *
29219d008b4SNeilBrown * @rqstp: the request context
29319d008b4SNeilBrown * @fhp: the file handle of the directory
29419d008b4SNeilBrown * @name: the component name, or %NULL to look up parent
29519d008b4SNeilBrown * @len: length of name to examine
29619d008b4SNeilBrown * @resfh: pointer to pre-initialised filehandle to hold result.
29719d008b4SNeilBrown *
2986c0a654dSJ. Bruce Fields * Look up one component of a pathname.
2996c0a654dSJ. Bruce Fields * N.B. After this call _both_ fhp and resfh need an fh_put
3006c0a654dSJ. Bruce Fields *
3016c0a654dSJ. Bruce Fields * If the lookup would cross a mountpoint, and the mounted filesystem
3026c0a654dSJ. Bruce Fields * is exported to the client with NFSEXP_NOHIDE, then the lookup is
3036c0a654dSJ. Bruce Fields * accepted as it stands and the mounted directory is
3046c0a654dSJ. Bruce Fields * returned. Otherwise the covered directory is returned.
3056c0a654dSJ. Bruce Fields * NOTE: this mountpoint crossing is not supported properly by all
3066c0a654dSJ. Bruce Fields * clients and is explicitly disallowed for NFSv3
30719d008b4SNeilBrown *
3086c0a654dSJ. Bruce Fields */
3096c0a654dSJ. Bruce Fields __be32
nfsd_lookup(struct svc_rqst * rqstp,struct svc_fh * fhp,const char * name,unsigned int len,struct svc_fh * resfh)3106c0a654dSJ. Bruce Fields nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
3115a022fc8SChuck Lever unsigned int len, struct svc_fh *resfh)
3126c0a654dSJ. Bruce Fields {
3136c0a654dSJ. Bruce Fields struct svc_export *exp;
3146c0a654dSJ. Bruce Fields struct dentry *dentry;
3156c0a654dSJ. Bruce Fields __be32 err;
3166c0a654dSJ. Bruce Fields
31729a78a3eSJ. Bruce Fields err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC);
31829a78a3eSJ. Bruce Fields if (err)
31929a78a3eSJ. Bruce Fields return err;
3206c0a654dSJ. Bruce Fields err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
3216c0a654dSJ. Bruce Fields if (err)
3226c0a654dSJ. Bruce Fields return err;
32332c1eb0cSAndy Adamson err = check_nfsd_access(exp, rqstp);
32432c1eb0cSAndy Adamson if (err)
32532c1eb0cSAndy Adamson goto out;
3261da177e4SLinus Torvalds /*
3271da177e4SLinus Torvalds * Note: we compose the file handle now, but as the
3281da177e4SLinus Torvalds * dentry may be negative, it may need to be updated.
3291da177e4SLinus Torvalds */
3301da177e4SLinus Torvalds err = fh_compose(resfh, exp, dentry, fhp);
3312b0143b5SDavid Howells if (!err && d_really_is_negative(dentry))
3321da177e4SLinus Torvalds err = nfserr_noent;
33332c1eb0cSAndy Adamson out:
3341da177e4SLinus Torvalds dput(dentry);
3351da177e4SLinus Torvalds exp_put(exp);
3361da177e4SLinus Torvalds return err;
3371da177e4SLinus Torvalds }
3381da177e4SLinus Torvalds
3391b2021bdSTrond Myklebust static void
commit_reset_write_verifier(struct nfsd_net * nn,struct svc_rqst * rqstp,int err)3401b2021bdSTrond Myklebust commit_reset_write_verifier(struct nfsd_net *nn, struct svc_rqst *rqstp,
3411b2021bdSTrond Myklebust int err)
3421b2021bdSTrond Myklebust {
3431b2021bdSTrond Myklebust switch (err) {
3441b2021bdSTrond Myklebust case -EAGAIN:
3451b2021bdSTrond Myklebust case -ESTALE:
3461b2021bdSTrond Myklebust /*
3471b2021bdSTrond Myklebust * Neither of these are the result of a problem with
3481b2021bdSTrond Myklebust * durable storage, so avoid a write verifier reset.
3491b2021bdSTrond Myklebust */
3501b2021bdSTrond Myklebust break;
3511b2021bdSTrond Myklebust default:
3521b2021bdSTrond Myklebust nfsd_reset_write_verifier(nn);
3531b2021bdSTrond Myklebust trace_nfsd_writeverf_reset(nn, rqstp, err);
3541b2021bdSTrond Myklebust }
3551b2021bdSTrond Myklebust }
3561b2021bdSTrond Myklebust
357f501912aSBen Myers /*
358f501912aSBen Myers * Commit metadata changes to stable storage.
359f501912aSBen Myers */
360f501912aSBen Myers static int
commit_inode_metadata(struct inode * inode)36157f64034STrond Myklebust commit_inode_metadata(struct inode *inode)
362f501912aSBen Myers {
363f501912aSBen Myers const struct export_operations *export_ops = inode->i_sb->s_export_op;
364f501912aSBen Myers
365c3765016SChristoph Hellwig if (export_ops->commit_metadata)
366c3765016SChristoph Hellwig return export_ops->commit_metadata(inode);
367c3765016SChristoph Hellwig return sync_inode_metadata(inode, 1);
368f501912aSBen Myers }
3696c0a654dSJ. Bruce Fields
37057f64034STrond Myklebust static int
commit_metadata(struct svc_fh * fhp)37157f64034STrond Myklebust commit_metadata(struct svc_fh *fhp)
37257f64034STrond Myklebust {
37357f64034STrond Myklebust struct inode *inode = d_inode(fhp->fh_dentry);
37457f64034STrond Myklebust
37557f64034STrond Myklebust if (!EX_ISSYNC(fhp->fh_export))
37657f64034STrond Myklebust return 0;
37757f64034STrond Myklebust return commit_inode_metadata(inode);
37857f64034STrond Myklebust }
37957f64034STrond Myklebust
3801da177e4SLinus Torvalds /*
381818e5a22SChristoph Hellwig * Go over the attributes and take care of the small differences between
382818e5a22SChristoph Hellwig * NFS semantics and what Linux expects.
383818e5a22SChristoph Hellwig */
384818e5a22SChristoph Hellwig static void
nfsd_sanitize_attrs(struct inode * inode,struct iattr * iap)385818e5a22SChristoph Hellwig nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
386818e5a22SChristoph Hellwig {
38700801cd9SNeilBrown /* Ignore mode updates on symlinks */
38800801cd9SNeilBrown if (S_ISLNK(inode->i_mode))
38900801cd9SNeilBrown iap->ia_valid &= ~ATTR_MODE;
39000801cd9SNeilBrown
391818e5a22SChristoph Hellwig /* sanitize the mode change */
392818e5a22SChristoph Hellwig if (iap->ia_valid & ATTR_MODE) {
393818e5a22SChristoph Hellwig iap->ia_mode &= S_IALLUGO;
394818e5a22SChristoph Hellwig iap->ia_mode |= (inode->i_mode & ~S_IALLUGO);
395818e5a22SChristoph Hellwig }
396818e5a22SChristoph Hellwig
397818e5a22SChristoph Hellwig /* Revoke setuid/setgid on chown */
398818e5a22SChristoph Hellwig if (!S_ISDIR(inode->i_mode) &&
399c4fa6d7cSStanislav Kholmanskikh ((iap->ia_valid & ATTR_UID) || (iap->ia_valid & ATTR_GID))) {
400818e5a22SChristoph Hellwig iap->ia_valid |= ATTR_KILL_PRIV;
401818e5a22SChristoph Hellwig if (iap->ia_valid & ATTR_MODE) {
402818e5a22SChristoph Hellwig /* we're setting mode too, just clear the s*id bits */
403818e5a22SChristoph Hellwig iap->ia_mode &= ~S_ISUID;
404818e5a22SChristoph Hellwig if (iap->ia_mode & S_IXGRP)
405818e5a22SChristoph Hellwig iap->ia_mode &= ~S_ISGID;
406818e5a22SChristoph Hellwig } else {
407818e5a22SChristoph Hellwig /* set ATTR_KILL_* bits and let VFS handle it */
4082d8ae8c4SChristian Brauner iap->ia_valid |= ATTR_KILL_SUID;
4092d8ae8c4SChristian Brauner iap->ia_valid |=
4102d8ae8c4SChristian Brauner setattr_should_drop_sgid(&nop_mnt_idmap, inode);
411818e5a22SChristoph Hellwig }
412818e5a22SChristoph Hellwig }
413818e5a22SChristoph Hellwig }
414818e5a22SChristoph Hellwig
4150839ffb8SJ. Bruce Fields static __be32
nfsd_get_write_access(struct svc_rqst * rqstp,struct svc_fh * fhp,struct iattr * iap)4160839ffb8SJ. Bruce Fields nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp,
4170839ffb8SJ. Bruce Fields struct iattr *iap)
4180839ffb8SJ. Bruce Fields {
4190839ffb8SJ. Bruce Fields struct inode *inode = d_inode(fhp->fh_dentry);
4200839ffb8SJ. Bruce Fields
4210839ffb8SJ. Bruce Fields if (iap->ia_size < inode->i_size) {
4220839ffb8SJ. Bruce Fields __be32 err;
4230839ffb8SJ. Bruce Fields
4240839ffb8SJ. Bruce Fields err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
4250839ffb8SJ. Bruce Fields NFSD_MAY_TRUNC | NFSD_MAY_OWNER_OVERRIDE);
4260839ffb8SJ. Bruce Fields if (err)
4270839ffb8SJ. Bruce Fields return err;
4280839ffb8SJ. Bruce Fields }
429f7e33bdbSJeff Layton return nfserrno(get_write_access(inode));
4300839ffb8SJ. Bruce Fields }
4310839ffb8SJ. Bruce Fields
__nfsd_setattr(struct dentry * dentry,struct iattr * iap)432c0aa1913SChuck Lever static int __nfsd_setattr(struct dentry *dentry, struct iattr *iap)
433c0aa1913SChuck Lever {
434c0aa1913SChuck Lever int host_err;
435c0aa1913SChuck Lever
436c0aa1913SChuck Lever if (iap->ia_valid & ATTR_SIZE) {
437818e5a22SChristoph Hellwig /*
438c0aa1913SChuck Lever * RFC5661, Section 18.30.4:
439c0aa1913SChuck Lever * Changing the size of a file with SETATTR indirectly
440c0aa1913SChuck Lever * changes the time_modify and change attributes.
441c0aa1913SChuck Lever *
442c0aa1913SChuck Lever * (and similar for the older RFCs)
443c0aa1913SChuck Lever */
444c0aa1913SChuck Lever struct iattr size_attr = {
445c0aa1913SChuck Lever .ia_valid = ATTR_SIZE | ATTR_CTIME | ATTR_MTIME,
446c0aa1913SChuck Lever .ia_size = iap->ia_size,
447c0aa1913SChuck Lever };
448c0aa1913SChuck Lever
449c0aa1913SChuck Lever if (iap->ia_size < 0)
450c0aa1913SChuck Lever return -EFBIG;
451c0aa1913SChuck Lever
452abf08576SChristian Brauner host_err = notify_change(&nop_mnt_idmap, dentry, &size_attr, NULL);
453c0aa1913SChuck Lever if (host_err)
454c0aa1913SChuck Lever return host_err;
455c0aa1913SChuck Lever iap->ia_valid &= ~ATTR_SIZE;
456c0aa1913SChuck Lever
457c0aa1913SChuck Lever /*
458c0aa1913SChuck Lever * Avoid the additional setattr call below if the only other
459c0aa1913SChuck Lever * attribute that the client sends is the mtime, as we update
460c0aa1913SChuck Lever * it as part of the size change above.
461c0aa1913SChuck Lever */
462c0aa1913SChuck Lever if ((iap->ia_valid & ~ATTR_MTIME) == 0)
463c0aa1913SChuck Lever return 0;
464c0aa1913SChuck Lever }
465c0aa1913SChuck Lever
466c0aa1913SChuck Lever if (!iap->ia_valid)
467c0aa1913SChuck Lever return 0;
468c0aa1913SChuck Lever
469c0aa1913SChuck Lever iap->ia_valid |= ATTR_CTIME;
470abf08576SChristian Brauner return notify_change(&nop_mnt_idmap, dentry, iap, NULL);
471c0aa1913SChuck Lever }
472c0aa1913SChuck Lever
473c0aa1913SChuck Lever /**
474c0aa1913SChuck Lever * nfsd_setattr - Set various file attributes.
475c0aa1913SChuck Lever * @rqstp: controlling RPC transaction
476c0aa1913SChuck Lever * @fhp: filehandle of target
477c0aa1913SChuck Lever * @attr: attributes to set
478c0aa1913SChuck Lever * @guardtime: do not act if ctime.tv_sec does not match this timestamp
479c0aa1913SChuck Lever *
480c0aa1913SChuck Lever * This call may adjust the contents of @attr (in particular, this
481c0aa1913SChuck Lever * call may change the bits in the na_iattr.ia_valid field).
482c0aa1913SChuck Lever *
483c0aa1913SChuck Lever * Returns nfs_ok on success, otherwise an NFS status code is
484c0aa1913SChuck Lever * returned. Caller must release @fhp by calling fh_put in either
485c0aa1913SChuck Lever * case.
4861da177e4SLinus Torvalds */
4876264d69dSAl Viro __be32
nfsd_setattr(struct svc_rqst * rqstp,struct svc_fh * fhp,struct nfsd_attrs * attr,const struct timespec64 * guardtime)4887fe2a71dSNeilBrown nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
48924d92de9STrond Myklebust struct nfsd_attrs *attr, const struct timespec64 *guardtime)
4901da177e4SLinus Torvalds {
4911da177e4SLinus Torvalds struct dentry *dentry;
4921da177e4SLinus Torvalds struct inode *inode;
4937fe2a71dSNeilBrown struct iattr *iap = attr->na_iattr;
4948837abcaSMiklos Szeredi int accmode = NFSD_MAY_SATTR;
495175a4eb7SAl Viro umode_t ftype = 0;
4966264d69dSAl Viro __be32 err;
4976412e44cSTrond Myklebust int host_err = 0;
4989f67f189SJ. Bruce Fields bool get_write_count;
499758e99feSChristoph Hellwig bool size_change = (iap->ia_valid & ATTR_SIZE);
50034b91ddaSChuck Lever int retries;
5011da177e4SLinus Torvalds
502255fbca6Szhengbin if (iap->ia_valid & ATTR_SIZE) {
5038837abcaSMiklos Szeredi accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
5041da177e4SLinus Torvalds ftype = S_IFREG;
505255fbca6Szhengbin }
506255fbca6Szhengbin
507255fbca6Szhengbin /*
508255fbca6Szhengbin * If utimes(2) and friends are called with times not NULL, we should
509255fbca6Szhengbin * not set NFSD_MAY_WRITE bit. Otherwise fh_verify->nfsd_permission
510e977cc83SGeert Uytterhoeven * will return EACCES, when the caller's effective UID does not match
511255fbca6Szhengbin * the owner of the file, and the caller is not privileged. In this
512255fbca6Szhengbin * situation, we should return EPERM(notify_change will return this).
513255fbca6Szhengbin */
514255fbca6Szhengbin if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME)) {
515255fbca6Szhengbin accmode |= NFSD_MAY_OWNER_OVERRIDE;
516255fbca6Szhengbin if (!(iap->ia_valid & (ATTR_ATIME_SET | ATTR_MTIME_SET)))
517255fbca6Szhengbin accmode |= NFSD_MAY_WRITE;
518255fbca6Szhengbin }
5191da177e4SLinus Torvalds
5209f67f189SJ. Bruce Fields /* Callers that do fh_verify should do the fh_want_write: */
5219f67f189SJ. Bruce Fields get_write_count = !fhp->fh_dentry;
5229f67f189SJ. Bruce Fields
5231da177e4SLinus Torvalds /* Get inode */
5241da177e4SLinus Torvalds err = fh_verify(rqstp, fhp, ftype, accmode);
52515b7a1b8SNeilBrown if (err)
526758e99feSChristoph Hellwig return err;
5279f67f189SJ. Bruce Fields if (get_write_count) {
5289f67f189SJ. Bruce Fields host_err = fh_want_write(fhp);
5299f67f189SJ. Bruce Fields if (host_err)
530758e99feSChristoph Hellwig goto out;
5319f67f189SJ. Bruce Fields }
5321da177e4SLinus Torvalds
5331da177e4SLinus Torvalds dentry = fhp->fh_dentry;
5342b0143b5SDavid Howells inode = d_inode(dentry);
5351da177e4SLinus Torvalds
536818e5a22SChristoph Hellwig nfsd_sanitize_attrs(inode, iap);
5371da177e4SLinus Torvalds
538f0c63124SChristoph Hellwig /*
53941f53350SChristoph Hellwig * The size case is special, it changes the file in addition to the
540783112f7SChristoph Hellwig * attributes, and file systems don't expect it to be mixed with
541783112f7SChristoph Hellwig * "random" attribute changes. We thus split out the size change
542783112f7SChristoph Hellwig * into a separate call to ->setattr, and do the rest as a separate
543783112f7SChristoph Hellwig * setattr call.
544f0c63124SChristoph Hellwig */
545758e99feSChristoph Hellwig if (size_change) {
5460839ffb8SJ. Bruce Fields err = nfsd_get_write_access(rqstp, fhp, iap);
5470839ffb8SJ. Bruce Fields if (err)
548758e99feSChristoph Hellwig return err;
549783112f7SChristoph Hellwig }
55041f53350SChristoph Hellwig
551bb4d53d6SNeilBrown inode_lock(inode);
5526412e44cSTrond Myklebust err = fh_fill_pre_attrs(fhp);
5536412e44cSTrond Myklebust if (err)
5546412e44cSTrond Myklebust goto out_unlock;
55524d92de9STrond Myklebust
55624d92de9STrond Myklebust if (guardtime) {
55724d92de9STrond Myklebust struct timespec64 ctime = inode_get_ctime(inode);
55824d92de9STrond Myklebust if ((u32)guardtime->tv_sec != (u32)ctime.tv_sec ||
55924d92de9STrond Myklebust guardtime->tv_nsec != ctime.tv_nsec) {
56024d92de9STrond Myklebust err = nfserr_notsync;
56124d92de9STrond Myklebust goto out_fill_attrs;
56224d92de9STrond Myklebust }
56324d92de9STrond Myklebust }
56424d92de9STrond Myklebust
56534b91ddaSChuck Lever for (retries = 1;;) {
566d53d7008SJeff Layton struct iattr attrs;
567d53d7008SJeff Layton
568d53d7008SJeff Layton /*
569d53d7008SJeff Layton * notify_change() can alter its iattr argument, making
570d53d7008SJeff Layton * @iap unsuitable for submission multiple times. Make a
571d53d7008SJeff Layton * copy for every loop iteration.
572d53d7008SJeff Layton */
573d53d7008SJeff Layton attrs = *iap;
574d53d7008SJeff Layton host_err = __nfsd_setattr(dentry, &attrs);
57534b91ddaSChuck Lever if (host_err != -EAGAIN || !retries--)
57634b91ddaSChuck Lever break;
57734b91ddaSChuck Lever if (!nfsd_wait_for_delegreturn(rqstp, inode))
57834b91ddaSChuck Lever break;
57934b91ddaSChuck Lever }
580d6a97d3fSNeilBrown if (attr->na_seclabel && attr->na_seclabel->len)
581d6a97d3fSNeilBrown attr->na_labelerr = security_inode_setsecctx(dentry,
582d6a97d3fSNeilBrown attr->na_seclabel->data, attr->na_seclabel->len);
583c0cbe707SNeilBrown if (IS_ENABLED(CONFIG_FS_POSIX_ACL) && attr->na_pacl)
58413e83a49SChristian Brauner attr->na_aclerr = set_posix_acl(&nop_mnt_idmap,
585138060baSChristian Brauner dentry, ACL_TYPE_ACCESS,
586c0cbe707SNeilBrown attr->na_pacl);
587c0cbe707SNeilBrown if (IS_ENABLED(CONFIG_FS_POSIX_ACL) &&
588c0cbe707SNeilBrown !attr->na_aclerr && attr->na_dpacl && S_ISDIR(inode->i_mode))
58913e83a49SChristian Brauner attr->na_aclerr = set_posix_acl(&nop_mnt_idmap,
590138060baSChristian Brauner dentry, ACL_TYPE_DEFAULT,
591c0cbe707SNeilBrown attr->na_dpacl);
59224d92de9STrond Myklebust out_fill_attrs:
5937d5a352cSChuck Lever /*
5947d5a352cSChuck Lever * RFC 1813 Section 3.3.2 does not mandate that an NFS server
5957d5a352cSChuck Lever * returns wcc_data for SETATTR. Some client implementations
5967d5a352cSChuck Lever * depend on receiving wcc_data, however, to sort out partial
5977d5a352cSChuck Lever * updates (eg., the client requested that size and mode be
5987d5a352cSChuck Lever * modified, but the server changed only the file mode).
5997d5a352cSChuck Lever */
6006412e44cSTrond Myklebust fh_fill_post_attrs(fhp);
6016412e44cSTrond Myklebust out_unlock:
602bb4d53d6SNeilBrown inode_unlock(inode);
6030839ffb8SJ. Bruce Fields if (size_change)
6040839ffb8SJ. Bruce Fields put_write_access(inode);
6050839ffb8SJ. Bruce Fields out:
606758e99feSChristoph Hellwig if (!host_err)
607758e99feSChristoph Hellwig host_err = commit_metadata(fhp);
6086412e44cSTrond Myklebust return err != 0 ? err : nfserrno(host_err);
6091da177e4SLinus Torvalds }
6101da177e4SLinus Torvalds
6115be196e5SChristoph Hellwig #if defined(CONFIG_NFSD_V4)
6129b4146e8SChuck Lever /*
6139b4146e8SChuck Lever * NFS junction information is stored in an extended attribute.
6149b4146e8SChuck Lever */
6159b4146e8SChuck Lever #define NFSD_JUNCTION_XATTR_NAME XATTR_TRUSTED_PREFIX "junction.nfs"
6169b4146e8SChuck Lever
6179b4146e8SChuck Lever /**
6189b4146e8SChuck Lever * nfsd4_is_junction - Test if an object could be an NFS junction
6199b4146e8SChuck Lever *
6209b4146e8SChuck Lever * @dentry: object to test
6219b4146e8SChuck Lever *
6229b4146e8SChuck Lever * Returns 1 if "dentry" appears to contain NFS junction information.
6239b4146e8SChuck Lever * Otherwise 0 is returned.
6249b4146e8SChuck Lever */
nfsd4_is_junction(struct dentry * dentry)62511fcee02STrond Myklebust int nfsd4_is_junction(struct dentry *dentry)
62611fcee02STrond Myklebust {
6272b0143b5SDavid Howells struct inode *inode = d_inode(dentry);
62811fcee02STrond Myklebust
62911fcee02STrond Myklebust if (inode == NULL)
63011fcee02STrond Myklebust return 0;
63111fcee02STrond Myklebust if (inode->i_mode & S_IXUGO)
63211fcee02STrond Myklebust return 0;
63311fcee02STrond Myklebust if (!(inode->i_mode & S_ISVTX))
63411fcee02STrond Myklebust return 0;
6354609e1f1SChristian Brauner if (vfs_getxattr(&nop_mnt_idmap, dentry, NFSD_JUNCTION_XATTR_NAME,
636c7c7a1a1STycho Andersen NULL, 0) <= 0)
63711fcee02STrond Myklebust return 0;
63811fcee02STrond Myklebust return 1;
63911fcee02STrond Myklebust }
64018032ca0SDavid Quigley
nfsd4_get_cstate(struct svc_rqst * rqstp)641a2f4c3faSTrond Myklebust static struct nfsd4_compound_state *nfsd4_get_cstate(struct svc_rqst *rqstp)
642a2f4c3faSTrond Myklebust {
643a2f4c3faSTrond Myklebust return &((struct nfsd4_compoundres *)rqstp->rq_resp)->cstate;
644a2f4c3faSTrond Myklebust }
645a2f4c3faSTrond Myklebust
nfsd4_clone_file_range(struct svc_rqst * rqstp,struct nfsd_file * nf_src,u64 src_pos,struct nfsd_file * nf_dst,u64 dst_pos,u64 count,bool sync)646a2f4c3faSTrond Myklebust __be32 nfsd4_clone_file_range(struct svc_rqst *rqstp,
647a2f4c3faSTrond Myklebust struct nfsd_file *nf_src, u64 src_pos,
648a2f4c3faSTrond Myklebust struct nfsd_file *nf_dst, u64 dst_pos,
649a2f4c3faSTrond Myklebust u64 count, bool sync)
650ffa0160aSChristoph Hellwig {
651b66ae6ddSTrond Myklebust struct file *src = nf_src->nf_file;
652b66ae6ddSTrond Myklebust struct file *dst = nf_dst->nf_file;
653555dbf1aSTrond Myklebust errseq_t since;
65442ec3d4cSDarrick J. Wong loff_t cloned;
6551b28d756STrond Myklebust __be32 ret = 0;
65642ec3d4cSDarrick J. Wong
657555dbf1aSTrond Myklebust since = READ_ONCE(dst->f_wb_err);
658452ce659SDarrick J. Wong cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0);
6591b28d756STrond Myklebust if (cloned < 0) {
6601b28d756STrond Myklebust ret = nfserrno(cloned);
6611b28d756STrond Myklebust goto out_err;
6621b28d756STrond Myklebust }
6631b28d756STrond Myklebust if (count && cloned != count) {
6641b28d756STrond Myklebust ret = nfserrno(-EINVAL);
6651b28d756STrond Myklebust goto out_err;
6661b28d756STrond Myklebust }
667a25e3726STrond Myklebust if (sync) {
668a25e3726STrond Myklebust loff_t dst_end = count ? dst_pos + count - 1 : LLONG_MAX;
669a25e3726STrond Myklebust int status = vfs_fsync_range(dst, dst_pos, dst_end, 0);
67057f64034STrond Myklebust
67157f64034STrond Myklebust if (!status)
672555dbf1aSTrond Myklebust status = filemap_check_wb_err(dst->f_mapping, since);
673555dbf1aSTrond Myklebust if (!status)
67457f64034STrond Myklebust status = commit_inode_metadata(file_inode(src));
6751b28d756STrond Myklebust if (status < 0) {
67675acacb6SChuck Lever struct nfsd_net *nn = net_generic(nf_dst->nf_net,
67775acacb6SChuck Lever nfsd_net_id);
67875acacb6SChuck Lever
679a2f4c3faSTrond Myklebust trace_nfsd_clone_file_range_err(rqstp,
680a2f4c3faSTrond Myklebust &nfsd4_get_cstate(rqstp)->save_fh,
681a2f4c3faSTrond Myklebust src_pos,
682a2f4c3faSTrond Myklebust &nfsd4_get_cstate(rqstp)->current_fh,
683a2f4c3faSTrond Myklebust dst_pos,
684a2f4c3faSTrond Myklebust count, status);
6851b2021bdSTrond Myklebust commit_reset_write_verifier(nn, rqstp, status);
6861b28d756STrond Myklebust ret = nfserrno(status);
687a25e3726STrond Myklebust }
6881b28d756STrond Myklebust }
6891b28d756STrond Myklebust out_err:
6901b28d756STrond Myklebust return ret;
691ffa0160aSChristoph Hellwig }
692ffa0160aSChristoph Hellwig
nfsd_copy_file_range(struct file * src,u64 src_pos,struct file * dst,u64 dst_pos,u64 count)69329ae7f9dSAnna Schumaker ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst,
69429ae7f9dSAnna Schumaker u64 dst_pos, u64 count)
69529ae7f9dSAnna Schumaker {
696868f9f2fSAmir Goldstein ssize_t ret;
69729ae7f9dSAnna Schumaker
69829ae7f9dSAnna Schumaker /*
69929ae7f9dSAnna Schumaker * Limit copy to 4MB to prevent indefinitely blocking an nfsd
70029ae7f9dSAnna Schumaker * thread and client rpc slot. The choice of 4MB is somewhat
70129ae7f9dSAnna Schumaker * arbitrary. We might instead base this on r/wsize, or make it
70229ae7f9dSAnna Schumaker * tunable, or use a time instead of a byte limit, or implement
70329ae7f9dSAnna Schumaker * asynchronous copy. In theory a client could also recognize a
70429ae7f9dSAnna Schumaker * limit like this and pipeline multiple COPY requests.
70529ae7f9dSAnna Schumaker */
70629ae7f9dSAnna Schumaker count = min_t(u64, count, 1 << 22);
707868f9f2fSAmir Goldstein ret = vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0);
708868f9f2fSAmir Goldstein
709868f9f2fSAmir Goldstein if (ret == -EOPNOTSUPP || ret == -EXDEV)
71010bc8e4aSAmir Goldstein ret = vfs_copy_file_range(src, src_pos, dst, dst_pos, count,
71110bc8e4aSAmir Goldstein COPY_FILE_SPLICE);
712868f9f2fSAmir Goldstein return ret;
71329ae7f9dSAnna Schumaker }
71429ae7f9dSAnna Schumaker
nfsd4_vfs_fallocate(struct svc_rqst * rqstp,struct svc_fh * fhp,struct file * file,loff_t offset,loff_t len,int flags)71595d871f0SAnna Schumaker __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp,
71695d871f0SAnna Schumaker struct file *file, loff_t offset, loff_t len,
71795d871f0SAnna Schumaker int flags)
71895d871f0SAnna Schumaker {
71995d871f0SAnna Schumaker int error;
72095d871f0SAnna Schumaker
72195d871f0SAnna Schumaker if (!S_ISREG(file_inode(file)->i_mode))
72295d871f0SAnna Schumaker return nfserr_inval;
72395d871f0SAnna Schumaker
72495d871f0SAnna Schumaker error = vfs_fallocate(file, flags, offset, len);
72595d871f0SAnna Schumaker if (!error)
72695d871f0SAnna Schumaker error = commit_metadata(fhp);
72795d871f0SAnna Schumaker
72895d871f0SAnna Schumaker return nfserrno(error);
72995d871f0SAnna Schumaker }
7306a85d6c7SJ. Bruce Fields #endif /* defined(CONFIG_NFSD_V4) */
7311da177e4SLinus Torvalds
7321da177e4SLinus Torvalds /*
7331da177e4SLinus Torvalds * Check server access rights to a file system object
7341da177e4SLinus Torvalds */
7351da177e4SLinus Torvalds struct accessmap {
7361da177e4SLinus Torvalds u32 access;
7371da177e4SLinus Torvalds int how;
7381da177e4SLinus Torvalds };
7391da177e4SLinus Torvalds static struct accessmap nfs3_regaccess[] = {
7408837abcaSMiklos Szeredi { NFS3_ACCESS_READ, NFSD_MAY_READ },
7418837abcaSMiklos Szeredi { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
7428837abcaSMiklos Szeredi { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC },
7438837abcaSMiklos Szeredi { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE },
7441da177e4SLinus Torvalds
745c11d7fd1SFrank van der Linden #ifdef CONFIG_NFSD_V4
746c11d7fd1SFrank van der Linden { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
747c11d7fd1SFrank van der Linden { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
748c11d7fd1SFrank van der Linden { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
749c11d7fd1SFrank van der Linden #endif
750c11d7fd1SFrank van der Linden
7511da177e4SLinus Torvalds { 0, 0 }
7521da177e4SLinus Torvalds };
7531da177e4SLinus Torvalds
7541da177e4SLinus Torvalds static struct accessmap nfs3_diraccess[] = {
7558837abcaSMiklos Szeredi { NFS3_ACCESS_READ, NFSD_MAY_READ },
7568837abcaSMiklos Szeredi { NFS3_ACCESS_LOOKUP, NFSD_MAY_EXEC },
7578837abcaSMiklos Szeredi { NFS3_ACCESS_MODIFY, NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC},
7588837abcaSMiklos Szeredi { NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE },
7598837abcaSMiklos Szeredi { NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE },
7601da177e4SLinus Torvalds
761c11d7fd1SFrank van der Linden #ifdef CONFIG_NFSD_V4
762c11d7fd1SFrank van der Linden { NFS4_ACCESS_XAREAD, NFSD_MAY_READ },
763c11d7fd1SFrank van der Linden { NFS4_ACCESS_XAWRITE, NFSD_MAY_WRITE },
764c11d7fd1SFrank van der Linden { NFS4_ACCESS_XALIST, NFSD_MAY_READ },
765c11d7fd1SFrank van der Linden #endif
766c11d7fd1SFrank van der Linden
7671da177e4SLinus Torvalds { 0, 0 }
7681da177e4SLinus Torvalds };
7691da177e4SLinus Torvalds
7701da177e4SLinus Torvalds static struct accessmap nfs3_anyaccess[] = {
7711da177e4SLinus Torvalds /* Some clients - Solaris 2.6 at least, make an access call
7721da177e4SLinus Torvalds * to the server to check for access for things like /dev/null
7731da177e4SLinus Torvalds * (which really, the server doesn't care about). So
7741da177e4SLinus Torvalds * We provide simple access checking for them, looking
7751da177e4SLinus Torvalds * mainly at mode bits, and we make sure to ignore read-only
7761da177e4SLinus Torvalds * filesystem checks
7771da177e4SLinus Torvalds */
7788837abcaSMiklos Szeredi { NFS3_ACCESS_READ, NFSD_MAY_READ },
7798837abcaSMiklos Szeredi { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC },
7808837abcaSMiklos Szeredi { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
7818837abcaSMiklos Szeredi { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS },
7821da177e4SLinus Torvalds
7831da177e4SLinus Torvalds { 0, 0 }
7841da177e4SLinus Torvalds };
7851da177e4SLinus Torvalds
7866264d69dSAl Viro __be32
nfsd_access(struct svc_rqst * rqstp,struct svc_fh * fhp,u32 * access,u32 * supported)7871da177e4SLinus Torvalds nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported)
7881da177e4SLinus Torvalds {
7891da177e4SLinus Torvalds struct accessmap *map;
7901da177e4SLinus Torvalds struct svc_export *export;
7911da177e4SLinus Torvalds struct dentry *dentry;
7921da177e4SLinus Torvalds u32 query, result = 0, sresult = 0;
7936264d69dSAl Viro __be32 error;
7941da177e4SLinus Torvalds
7958837abcaSMiklos Szeredi error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
7961da177e4SLinus Torvalds if (error)
7971da177e4SLinus Torvalds goto out;
7981da177e4SLinus Torvalds
7991da177e4SLinus Torvalds export = fhp->fh_export;
8001da177e4SLinus Torvalds dentry = fhp->fh_dentry;
8011da177e4SLinus Torvalds
802e36cb0b8SDavid Howells if (d_is_reg(dentry))
8031da177e4SLinus Torvalds map = nfs3_regaccess;
804e36cb0b8SDavid Howells else if (d_is_dir(dentry))
8051da177e4SLinus Torvalds map = nfs3_diraccess;
8061da177e4SLinus Torvalds else
8071da177e4SLinus Torvalds map = nfs3_anyaccess;
8081da177e4SLinus Torvalds
8091da177e4SLinus Torvalds
8101da177e4SLinus Torvalds query = *access;
8111da177e4SLinus Torvalds for (; map->access; map++) {
8121da177e4SLinus Torvalds if (map->access & query) {
8136264d69dSAl Viro __be32 err2;
8141da177e4SLinus Torvalds
8151da177e4SLinus Torvalds sresult |= map->access;
8161da177e4SLinus Torvalds
8170ec757dfSJ. Bruce Fields err2 = nfsd_permission(rqstp, export, dentry, map->how);
8181da177e4SLinus Torvalds switch (err2) {
8191da177e4SLinus Torvalds case nfs_ok:
8201da177e4SLinus Torvalds result |= map->access;
8211da177e4SLinus Torvalds break;
8221da177e4SLinus Torvalds
8231da177e4SLinus Torvalds /* the following error codes just mean the access was not allowed,
8241da177e4SLinus Torvalds * rather than an error occurred */
8251da177e4SLinus Torvalds case nfserr_rofs:
8261da177e4SLinus Torvalds case nfserr_acces:
8271da177e4SLinus Torvalds case nfserr_perm:
8281da177e4SLinus Torvalds /* simply don't "or" in the access bit. */
8291da177e4SLinus Torvalds break;
8301da177e4SLinus Torvalds default:
8311da177e4SLinus Torvalds error = err2;
8321da177e4SLinus Torvalds goto out;
8331da177e4SLinus Torvalds }
8341da177e4SLinus Torvalds }
8351da177e4SLinus Torvalds }
8361da177e4SLinus Torvalds *access = result;
8371da177e4SLinus Torvalds if (supported)
8381da177e4SLinus Torvalds *supported = sresult;
8391da177e4SLinus Torvalds
8401da177e4SLinus Torvalds out:
8411da177e4SLinus Torvalds return error;
8421da177e4SLinus Torvalds }
8431da177e4SLinus Torvalds
nfsd_open_break_lease(struct inode * inode,int access)84465294c1fSJeff Layton int nfsd_open_break_lease(struct inode *inode, int access)
845105f4622SJ. Bruce Fields {
846105f4622SJ. Bruce Fields unsigned int mode;
8471da177e4SLinus Torvalds
848105f4622SJ. Bruce Fields if (access & NFSD_MAY_NOT_BREAK_LEASE)
849105f4622SJ. Bruce Fields return 0;
850105f4622SJ. Bruce Fields mode = (access & NFSD_MAY_WRITE) ? O_WRONLY : O_RDONLY;
851105f4622SJ. Bruce Fields return break_lease(inode, mode | O_NONBLOCK);
852105f4622SJ. Bruce Fields }
8531da177e4SLinus Torvalds
8541da177e4SLinus Torvalds /*
8551da177e4SLinus Torvalds * Open an existing file or directory.
856999448a8SBernd Schubert * The may_flags argument indicates the type of open (read/write/lock)
857999448a8SBernd Schubert * and additional flags.
8581da177e4SLinus Torvalds * N.B. After this call fhp needs an fh_put
8591da177e4SLinus Torvalds */
860d59b3515STrond Myklebust static int
__nfsd_open(struct svc_rqst * rqstp,struct svc_fh * fhp,umode_t type,int may_flags,struct file ** filp)86165294c1fSJeff Layton __nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
862999448a8SBernd Schubert int may_flags, struct file **filp)
8631da177e4SLinus Torvalds {
864765927b2SAl Viro struct path path;
8651da177e4SLinus Torvalds struct inode *inode;
8668519f994SKinglong Mee struct file *file;
8676264d69dSAl Viro int flags = O_RDONLY|O_LARGEFILE;
868d59b3515STrond Myklebust int host_err = -EPERM;
8691da177e4SLinus Torvalds
870765927b2SAl Viro path.mnt = fhp->fh_export->ex_path.mnt;
871765927b2SAl Viro path.dentry = fhp->fh_dentry;
8722b0143b5SDavid Howells inode = d_inode(path.dentry);
8731da177e4SLinus Torvalds
874999448a8SBernd Schubert if (IS_APPEND(inode) && (may_flags & NFSD_MAY_WRITE))
8751da177e4SLinus Torvalds goto out;
8761da177e4SLinus Torvalds
8771da177e4SLinus Torvalds if (!inode->i_fop)
8781da177e4SLinus Torvalds goto out;
8791da177e4SLinus Torvalds
880999448a8SBernd Schubert host_err = nfsd_open_break_lease(inode, may_flags);
8816264d69dSAl Viro if (host_err) /* NOMEM or WOULDBLOCK */
882d59b3515STrond Myklebust goto out;
8831da177e4SLinus Torvalds
884999448a8SBernd Schubert if (may_flags & NFSD_MAY_WRITE) {
885999448a8SBernd Schubert if (may_flags & NFSD_MAY_READ)
8869ecb6a08SJ. Bruce Fields flags = O_RDWR|O_LARGEFILE;
8879ecb6a08SJ. Bruce Fields else
8881da177e4SLinus Torvalds flags = O_WRONLY|O_LARGEFILE;
8891da177e4SLinus Torvalds }
890999448a8SBernd Schubert
8918519f994SKinglong Mee file = dentry_open(&path, flags, current_cred());
8928519f994SKinglong Mee if (IS_ERR(file)) {
8938519f994SKinglong Mee host_err = PTR_ERR(file);
894d59b3515STrond Myklebust goto out;
89506effdbbSBernd Schubert }
89606effdbbSBernd Schubert
8978f46ff57SRoberto Sassu host_err = security_file_post_open(file, may_flags);
8988519f994SKinglong Mee if (host_err) {
899fd891454SChristoph Hellwig fput(file);
900d59b3515STrond Myklebust goto out;
9018519f994SKinglong Mee }
9028519f994SKinglong Mee
9038519f994SKinglong Mee if (may_flags & NFSD_MAY_64BIT_COOKIE)
9048519f994SKinglong Mee file->f_mode |= FMODE_64BITHASH;
9058519f994SKinglong Mee else
9068519f994SKinglong Mee file->f_mode |= FMODE_32BITHASH;
9078519f994SKinglong Mee
9088519f994SKinglong Mee *filp = file;
9091da177e4SLinus Torvalds out:
910d59b3515STrond Myklebust return host_err;
91165294c1fSJeff Layton }
91265294c1fSJeff Layton
91365294c1fSJeff Layton __be32
nfsd_open(struct svc_rqst * rqstp,struct svc_fh * fhp,umode_t type,int may_flags,struct file ** filp)91465294c1fSJeff Layton nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type,
91565294c1fSJeff Layton int may_flags, struct file **filp)
91665294c1fSJeff Layton {
91765294c1fSJeff Layton __be32 err;
918d59b3515STrond Myklebust int host_err;
91912bcbd40SJeff Layton bool retried = false;
92065294c1fSJeff Layton
92165294c1fSJeff Layton /*
92265294c1fSJeff Layton * If we get here, then the client has already done an "open",
92365294c1fSJeff Layton * and (hopefully) checked permission - so allow OWNER_OVERRIDE
92465294c1fSJeff Layton * in case a chmod has now revoked permission.
92565294c1fSJeff Layton *
92665294c1fSJeff Layton * Arguably we should also allow the owner override for
92765294c1fSJeff Layton * directories, but we never have and it doesn't seem to have
92865294c1fSJeff Layton * caused anyone a problem. If we were to change this, note
92965294c1fSJeff Layton * also that our filldir callbacks would need a variant of
93065294c1fSJeff Layton * lookup_one_len that doesn't check permissions.
93165294c1fSJeff Layton */
93265294c1fSJeff Layton if (type == S_IFREG)
93365294c1fSJeff Layton may_flags |= NFSD_MAY_OWNER_OVERRIDE;
93412bcbd40SJeff Layton retry:
93565294c1fSJeff Layton err = fh_verify(rqstp, fhp, type, may_flags);
93612bcbd40SJeff Layton if (!err) {
937d59b3515STrond Myklebust host_err = __nfsd_open(rqstp, fhp, type, may_flags, filp);
938d59b3515STrond Myklebust if (host_err == -EOPENSTALE && !retried) {
93912bcbd40SJeff Layton retried = true;
94012bcbd40SJeff Layton fh_put(fhp);
94112bcbd40SJeff Layton goto retry;
94212bcbd40SJeff Layton }
943d59b3515STrond Myklebust err = nfserrno(host_err);
94412bcbd40SJeff Layton }
9451da177e4SLinus Torvalds return err;
9461da177e4SLinus Torvalds }
9471da177e4SLinus Torvalds
948f4d84c52SChuck Lever /**
949f4d84c52SChuck Lever * nfsd_open_verified - Open a regular file for the filecache
950f4d84c52SChuck Lever * @rqstp: RPC request
951f4d84c52SChuck Lever * @fhp: NFS filehandle of the file to open
952f4d84c52SChuck Lever * @may_flags: internal permission flags
953f4d84c52SChuck Lever * @filp: OUT: open "struct file *"
954f4d84c52SChuck Lever *
955d59b3515STrond Myklebust * Returns zero on success, or a negative errno value.
956f4d84c52SChuck Lever */
957d59b3515STrond Myklebust int
nfsd_open_verified(struct svc_rqst * rqstp,struct svc_fh * fhp,int may_flags,struct file ** filp)958f4d84c52SChuck Lever nfsd_open_verified(struct svc_rqst *rqstp, struct svc_fh *fhp, int may_flags,
959f4d84c52SChuck Lever struct file **filp)
96065294c1fSJeff Layton {
961ae191417SJens Axboe return __nfsd_open(rqstp, fhp, S_IFREG, may_flags, filp);
96265294c1fSJeff Layton }
96365294c1fSJeff Layton
9641da177e4SLinus Torvalds /*
965cf8208d0SJens Axboe * Grab and keep cached pages associated with a file in the svc_rqst
966dc97391eSDavid Howells * so that they can be passed to the network sendmsg routines
967cf8208d0SJens Axboe * directly. They will be released after the sending has completed.
9680f516248SChuck Lever *
9690f516248SChuck Lever * Return values: Number of bytes consumed, or -EIO if there are no
9700f516248SChuck Lever * remaining pages in rqstp->rq_pages.
9711da177e4SLinus Torvalds */
9721da177e4SLinus Torvalds static int
nfsd_splice_actor(struct pipe_inode_info * pipe,struct pipe_buffer * buf,struct splice_desc * sd)973cf8208d0SJens Axboe nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
974cf8208d0SJens Axboe struct splice_desc *sd)
9751da177e4SLinus Torvalds {
976cf8208d0SJens Axboe struct svc_rqst *rqstp = sd->u.data;
977bfbfb618SAl Viro struct page *page = buf->page; // may be a compound one
978bfbfb618SAl Viro unsigned offset = buf->offset;
979ac8db824SChuck Lever struct page *last_page;
9801da177e4SLinus Torvalds
981ac8db824SChuck Lever last_page = page + (offset + sd->len - 1) / PAGE_SIZE;
98227c934ddSJeff Layton for (page += offset / PAGE_SIZE; page <= last_page; page++) {
98327c934ddSJeff Layton /*
984101df45eSDavid Howells * Skip page replacement when extending the contents of the
985101df45eSDavid Howells * current page. But note that we may get two zero_pages in a
986101df45eSDavid Howells * row from shmem.
98727c934ddSJeff Layton */
988101df45eSDavid Howells if (page == *(rqstp->rq_next_page - 1) &&
989101df45eSDavid Howells offset_in_page(rqstp->rq_res.page_base +
990101df45eSDavid Howells rqstp->rq_res.page_len))
99127c934ddSJeff Layton continue;
9920f516248SChuck Lever if (unlikely(!svc_rqst_replace_page(rqstp, page)))
9930f516248SChuck Lever return -EIO;
99427c934ddSJeff Layton }
995bfbfb618SAl Viro if (rqstp->rq_res.page_len == 0) // first call
996bfbfb618SAl Viro rqstp->rq_res.page_base = offset % PAGE_SIZE;
997c7e0b781SChuck Lever rqstp->rq_res.page_len += sd->len;
998c7e0b781SChuck Lever return sd->len;
9991da177e4SLinus Torvalds }
10001da177e4SLinus Torvalds
nfsd_direct_splice_actor(struct pipe_inode_info * pipe,struct splice_desc * sd)1001cf8208d0SJens Axboe static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
1002cf8208d0SJens Axboe struct splice_desc *sd)
1003cf8208d0SJens Axboe {
1004cf8208d0SJens Axboe return __splice_from_pipe(pipe, sd, nfsd_splice_actor);
1005cf8208d0SJens Axboe }
1006cf8208d0SJens Axboe
nfsd_eof_on_read(struct file * file,loff_t offset,ssize_t len,size_t expected)100783a63072STrond Myklebust static u32 nfsd_eof_on_read(struct file *file, loff_t offset, ssize_t len,
100883a63072STrond Myklebust size_t expected)
100983a63072STrond Myklebust {
101083a63072STrond Myklebust if (expected != 0 && len == 0)
101183a63072STrond Myklebust return 1;
101283a63072STrond Myklebust if (offset+len >= i_size_read(file_inode(file)))
101383a63072STrond Myklebust return 1;
101483a63072STrond Myklebust return 0;
101583a63072STrond Myklebust }
101683a63072STrond Myklebust
nfsd_finish_read(struct svc_rqst * rqstp,struct svc_fh * fhp,struct file * file,loff_t offset,unsigned long * count,u32 * eof,ssize_t host_err)101787c5942eSChuck Lever static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
101887c5942eSChuck Lever struct file *file, loff_t offset,
101983a63072STrond Myklebust unsigned long *count, u32 *eof, ssize_t host_err)
10201da177e4SLinus Torvalds {
1021dc97618dSJ. Bruce Fields if (host_err >= 0) {
10224b148854SJosef Bacik struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
10234b148854SJosef Bacik
10244b148854SJosef Bacik nfsd_stats_io_read_add(nn, fhp->fh_export, host_err);
102583a63072STrond Myklebust *eof = nfsd_eof_on_read(file, offset, host_err, *count);
1026dc97618dSJ. Bruce Fields *count = host_err;
1027dc97618dSJ. Bruce Fields fsnotify_access(file);
102887c5942eSChuck Lever trace_nfsd_read_io_done(rqstp, fhp, offset, *count);
1029dc97618dSJ. Bruce Fields return 0;
103087c5942eSChuck Lever } else {
103187c5942eSChuck Lever trace_nfsd_read_err(rqstp, fhp, offset, host_err);
1032dc97618dSJ. Bruce Fields return nfserrno(host_err);
1033dc97618dSJ. Bruce Fields }
103487c5942eSChuck Lever }
10351da177e4SLinus Torvalds
1036703d7521SChuck Lever /**
1037703d7521SChuck Lever * nfsd_splice_read - Perform a VFS read using a splice pipe
1038703d7521SChuck Lever * @rqstp: RPC transaction context
1039703d7521SChuck Lever * @fhp: file handle of file to be read
1040703d7521SChuck Lever * @file: opened struct file of file to be read
1041703d7521SChuck Lever * @offset: starting byte offset
1042703d7521SChuck Lever * @count: IN: requested number of bytes; OUT: number of bytes read
1043703d7521SChuck Lever * @eof: OUT: set non-zero if operation reached the end of the file
1044703d7521SChuck Lever *
1045703d7521SChuck Lever * Returns nfs_ok on success, otherwise an nfserr stat value is
1046703d7521SChuck Lever * returned.
1047703d7521SChuck Lever */
nfsd_splice_read(struct svc_rqst * rqstp,struct svc_fh * fhp,struct file * file,loff_t offset,unsigned long * count,u32 * eof)104887c5942eSChuck Lever __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
104983a63072STrond Myklebust struct file *file, loff_t offset, unsigned long *count,
105083a63072STrond Myklebust u32 *eof)
1051dc97618dSJ. Bruce Fields {
1052cf8208d0SJens Axboe struct splice_desc sd = {
1053cf8208d0SJens Axboe .len = 0,
1054cf8208d0SJens Axboe .total_len = *count,
1055cf8208d0SJens Axboe .pos = offset,
1056cf8208d0SJens Axboe .u.data = rqstp,
1057cf8208d0SJens Axboe };
105883a63072STrond Myklebust ssize_t host_err;
1059cf8208d0SJens Axboe
106087c5942eSChuck Lever trace_nfsd_read_splice(rqstp, fhp, offset, *count);
1061feebea75SAmir Goldstein host_err = rw_verify_area(READ, file, &offset, *count);
1062feebea75SAmir Goldstein if (!host_err)
1063feebea75SAmir Goldstein host_err = splice_direct_to_actor(file, &sd,
1064feebea75SAmir Goldstein nfsd_direct_splice_actor);
106583a63072STrond Myklebust return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
1066dc97618dSJ. Bruce Fields }
1067dc97618dSJ. Bruce Fields
1068507df40eSChuck Lever /**
1069507df40eSChuck Lever * nfsd_iter_read - Perform a VFS read using an iterator
1070507df40eSChuck Lever * @rqstp: RPC transaction context
1071507df40eSChuck Lever * @fhp: file handle of file to be read
1072507df40eSChuck Lever * @file: opened struct file of file to be read
1073507df40eSChuck Lever * @offset: starting byte offset
1074507df40eSChuck Lever * @count: IN: requested number of bytes; OUT: number of bytes read
1075507df40eSChuck Lever * @base: offset in first page of read buffer
1076507df40eSChuck Lever * @eof: OUT: set non-zero if operation reached the end of the file
1077507df40eSChuck Lever *
1078507df40eSChuck Lever * Some filesystems or situations cannot use nfsd_splice_read. This
1079507df40eSChuck Lever * function is the slightly less-performant fallback for those cases.
1080507df40eSChuck Lever *
1081507df40eSChuck Lever * Returns nfs_ok on success, otherwise an nfserr stat value is
1082507df40eSChuck Lever * returned.
1083507df40eSChuck Lever */
nfsd_iter_read(struct svc_rqst * rqstp,struct svc_fh * fhp,struct file * file,loff_t offset,unsigned long * count,unsigned int base,u32 * eof)1084507df40eSChuck Lever __be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
1085507df40eSChuck Lever struct file *file, loff_t offset, unsigned long *count,
1086507df40eSChuck Lever unsigned int base, u32 *eof)
1087507df40eSChuck Lever {
1088507df40eSChuck Lever unsigned long v, total;
1089507df40eSChuck Lever struct iov_iter iter;
1090507df40eSChuck Lever loff_t ppos = offset;
1091507df40eSChuck Lever struct page *page;
1092507df40eSChuck Lever ssize_t host_err;
1093507df40eSChuck Lever
1094507df40eSChuck Lever v = 0;
1095507df40eSChuck Lever total = *count;
1096507df40eSChuck Lever while (total) {
1097507df40eSChuck Lever page = *(rqstp->rq_next_page++);
1098507df40eSChuck Lever rqstp->rq_vec[v].iov_base = page_address(page) + base;
1099507df40eSChuck Lever rqstp->rq_vec[v].iov_len = min_t(size_t, total, PAGE_SIZE - base);
1100507df40eSChuck Lever total -= rqstp->rq_vec[v].iov_len;
1101507df40eSChuck Lever ++v;
1102507df40eSChuck Lever base = 0;
1103507df40eSChuck Lever }
1104507df40eSChuck Lever WARN_ON_ONCE(v > ARRAY_SIZE(rqstp->rq_vec));
1105507df40eSChuck Lever
1106507df40eSChuck Lever trace_nfsd_read_vector(rqstp, fhp, offset, *count);
1107507df40eSChuck Lever iov_iter_kvec(&iter, ITER_DEST, rqstp->rq_vec, v, *count);
1108507df40eSChuck Lever host_err = vfs_iter_read(file, &iter, &ppos, 0);
1109507df40eSChuck Lever return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
1110507df40eSChuck Lever }
1111507df40eSChuck Lever
1112d911df7bSJ. Bruce Fields /*
1113d911df7bSJ. Bruce Fields * Gathered writes: If another process is currently writing to the file,
1114d911df7bSJ. Bruce Fields * there's a high chance this is another nfsd (triggered by a bulk write
1115d911df7bSJ. Bruce Fields * from a client's biod). Rather than syncing the file with each write
1116d911df7bSJ. Bruce Fields * request, we sleep for 10 msec.
1117d911df7bSJ. Bruce Fields *
1118d911df7bSJ. Bruce Fields * I don't know if this roughly approximates C. Juszak's idea of
1119d911df7bSJ. Bruce Fields * gathered writes, but it's a nice and simple solution (IMHO), and it
1120d911df7bSJ. Bruce Fields * seems to work:-)
1121d911df7bSJ. Bruce Fields *
1122d911df7bSJ. Bruce Fields * Note: we do this only in the NFSv2 case, since v3 and higher have a
1123d911df7bSJ. Bruce Fields * better tool (separate unstable writes and commits) for solving this
1124d911df7bSJ. Bruce Fields * problem.
1125d911df7bSJ. Bruce Fields */
wait_for_concurrent_writes(struct file * file)1126d911df7bSJ. Bruce Fields static int wait_for_concurrent_writes(struct file *file)
1127d911df7bSJ. Bruce Fields {
1128496ad9aaSAl Viro struct inode *inode = file_inode(file);
1129d911df7bSJ. Bruce Fields static ino_t last_ino;
1130d911df7bSJ. Bruce Fields static dev_t last_dev;
1131d911df7bSJ. Bruce Fields int err = 0;
1132d911df7bSJ. Bruce Fields
1133d911df7bSJ. Bruce Fields if (atomic_read(&inode->i_writecount) > 1
1134d911df7bSJ. Bruce Fields || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) {
1135d911df7bSJ. Bruce Fields dprintk("nfsd: write defer %d\n", task_pid_nr(current));
1136d911df7bSJ. Bruce Fields msleep(10);
1137d911df7bSJ. Bruce Fields dprintk("nfsd: write resume %d\n", task_pid_nr(current));
1138d911df7bSJ. Bruce Fields }
1139d911df7bSJ. Bruce Fields
1140d911df7bSJ. Bruce Fields if (inode->i_state & I_DIRTY) {
1141d911df7bSJ. Bruce Fields dprintk("nfsd: write sync %d\n", task_pid_nr(current));
11428018ab05SChristoph Hellwig err = vfs_fsync(file, 0);
1143d911df7bSJ. Bruce Fields }
1144d911df7bSJ. Bruce Fields last_ino = inode->i_ino;
1145d911df7bSJ. Bruce Fields last_dev = inode->i_sb->s_dev;
1146d911df7bSJ. Bruce Fields return err;
1147d911df7bSJ. Bruce Fields }
1148d911df7bSJ. Bruce Fields
1149af90f707SChristoph Hellwig __be32
nfsd_vfs_write(struct svc_rqst * rqstp,struct svc_fh * fhp,struct nfsd_file * nf,loff_t offset,struct kvec * vec,int vlen,unsigned long * cnt,int stable,__be32 * verf)115016f8f894STrond Myklebust nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf,
11511da177e4SLinus Torvalds loff_t offset, struct kvec *vec, int vlen,
115219e0663fSTrond Myklebust unsigned long *cnt, int stable,
115319e0663fSTrond Myklebust __be32 *verf)
11541da177e4SLinus Torvalds {
1155fb7622c2SChuck Lever struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
115616f8f894STrond Myklebust struct file *file = nf->nf_file;
115701cbf385STrond Myklebust struct super_block *sb = file_inode(file)->i_sb;
11581da177e4SLinus Torvalds struct svc_export *exp;
115973da852eSChristoph Hellwig struct iov_iter iter;
1160555dbf1aSTrond Myklebust errseq_t since;
1161d890be15SChuck Lever __be32 nfserr;
11626264d69dSAl Viro int host_err;
116348e03bc5STrond Myklebust int use_wgather;
1164e49dbbf3SKent Overstreet loff_t pos = offset;
116501cbf385STrond Myklebust unsigned long exp_op_flags = 0;
11668658452eSNeilBrown unsigned int pflags = current->flags;
1167ddef7ed2SChristoph Hellwig rwf_t flags = 0;
116801cbf385STrond Myklebust bool restore_flags = false;
11698658452eSNeilBrown
1170d890be15SChuck Lever trace_nfsd_write_opened(rqstp, fhp, offset, *cnt);
1171d890be15SChuck Lever
117201cbf385STrond Myklebust if (sb->s_export_op)
117301cbf385STrond Myklebust exp_op_flags = sb->s_export_op->flags;
117401cbf385STrond Myklebust
117501cbf385STrond Myklebust if (test_bit(RQ_LOCAL, &rqstp->rq_flags) &&
117601cbf385STrond Myklebust !(exp_op_flags & EXPORT_OP_REMOTE_FS)) {
11778658452eSNeilBrown /*
1178a37b0715SNeilBrown * We want throttling in balance_dirty_pages()
1179a37b0715SNeilBrown * and shrink_inactive_list() to only consider
1180a37b0715SNeilBrown * the backingdev we are writing to, so that nfs to
11818658452eSNeilBrown * localhost doesn't cause nfsd to lock up due to all
11828658452eSNeilBrown * the client's dirty pages or its congested queue.
11838658452eSNeilBrown */
1184a37b0715SNeilBrown current->flags |= PF_LOCAL_THROTTLE;
118501cbf385STrond Myklebust restore_flags = true;
118601cbf385STrond Myklebust }
11871da177e4SLinus Torvalds
11881da177e4SLinus Torvalds exp = fhp->fh_export;
118948e03bc5STrond Myklebust use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp);
11901da177e4SLinus Torvalds
11911da177e4SLinus Torvalds if (!EX_ISSYNC(exp))
119254bbb7d2SKinglong Mee stable = NFS_UNSTABLE;
11931da177e4SLinus Torvalds
119424368aadSChristoph Hellwig if (stable && !use_wgather)
119524368aadSChristoph Hellwig flags |= RWF_SYNC;
119624368aadSChristoph Hellwig
1197de4eda9dSAl Viro iov_iter_kvec(&iter, ITER_SOURCE, vec, vlen, *cnt);
1198555dbf1aSTrond Myklebust since = READ_ONCE(file->f_wb_err);
1199f11ad7aaSChuck Lever if (verf)
12003988a578SChuck Lever nfsd_copy_write_verifier(verf, nn);
120173da852eSChristoph Hellwig host_err = vfs_iter_write(file, &iter, &pos, flags);
12027bf94c6bSTrond Myklebust if (host_err < 0) {
12031b2021bdSTrond Myklebust commit_reset_write_verifier(nn, rqstp, host_err);
1204e4636d53SJ. Bruce Fields goto out_nfserr;
12057bf94c6bSTrond Myklebust }
120609a80f2aSTrond Myklebust *cnt = host_err;
12074b148854SJosef Bacik nfsd_stats_io_write_add(nn, exp, *cnt);
12082a12a9d7SEric Paris fsnotify_modify(file);
1209555dbf1aSTrond Myklebust host_err = filemap_check_wb_err(file->f_mapping, since);
1210555dbf1aSTrond Myklebust if (host_err < 0)
1211555dbf1aSTrond Myklebust goto out_nfserr;
12121da177e4SLinus Torvalds
1213bbf2f098STrond Myklebust if (stable && use_wgather) {
1214d911df7bSJ. Bruce Fields host_err = wait_for_concurrent_writes(file);
12151b2021bdSTrond Myklebust if (host_err < 0)
12161b2021bdSTrond Myklebust commit_reset_write_verifier(nn, rqstp, host_err);
1217bbf2f098STrond Myklebust }
12181da177e4SLinus Torvalds
1219e4636d53SJ. Bruce Fields out_nfserr:
1220d890be15SChuck Lever if (host_err >= 0) {
1221d890be15SChuck Lever trace_nfsd_write_io_done(rqstp, fhp, offset, *cnt);
1222d890be15SChuck Lever nfserr = nfs_ok;
1223d890be15SChuck Lever } else {
1224d890be15SChuck Lever trace_nfsd_write_err(rqstp, fhp, offset, host_err);
1225d890be15SChuck Lever nfserr = nfserrno(host_err);
1226d890be15SChuck Lever }
122701cbf385STrond Myklebust if (restore_flags)
1228a37b0715SNeilBrown current_restore_flags(pflags, PF_LOCAL_THROTTLE);
1229d890be15SChuck Lever return nfserr;
12301da177e4SLinus Torvalds }
12311da177e4SLinus Torvalds
1232507df40eSChuck Lever /**
1233c21fd7a8SChuck Lever * nfsd_read_splice_ok - check if spliced reading is supported
1234c21fd7a8SChuck Lever * @rqstp: RPC transaction context
1235c21fd7a8SChuck Lever *
1236c21fd7a8SChuck Lever * Return values:
1237c21fd7a8SChuck Lever * %true: nfsd_splice_read() may be used
1238c21fd7a8SChuck Lever * %false: nfsd_splice_read() must not be used
1239c21fd7a8SChuck Lever *
1240c21fd7a8SChuck Lever * NFS READ normally uses splice to send data in-place. However the
1241c21fd7a8SChuck Lever * data in cache can change after the reply's MIC is computed but
1242c21fd7a8SChuck Lever * before the RPC reply is sent. To prevent the client from
1243c21fd7a8SChuck Lever * rejecting the server-computed MIC in this somewhat rare case, do
1244c21fd7a8SChuck Lever * not use splice with the GSS integrity and privacy services.
1245c21fd7a8SChuck Lever */
nfsd_read_splice_ok(struct svc_rqst * rqstp)1246c21fd7a8SChuck Lever bool nfsd_read_splice_ok(struct svc_rqst *rqstp)
1247c21fd7a8SChuck Lever {
1248c21fd7a8SChuck Lever switch (svc_auth_flavor(rqstp)) {
1249c21fd7a8SChuck Lever case RPC_AUTH_GSS_KRB5I:
1250c21fd7a8SChuck Lever case RPC_AUTH_GSS_KRB5P:
1251c21fd7a8SChuck Lever return false;
1252c21fd7a8SChuck Lever }
1253c21fd7a8SChuck Lever return true;
1254c21fd7a8SChuck Lever }
1255c21fd7a8SChuck Lever
1256c21fd7a8SChuck Lever /**
1257507df40eSChuck Lever * nfsd_read - Read data from a file
1258507df40eSChuck Lever * @rqstp: RPC transaction context
1259507df40eSChuck Lever * @fhp: file handle of file to be read
1260507df40eSChuck Lever * @offset: starting byte offset
1261507df40eSChuck Lever * @count: IN: requested number of bytes; OUT: number of bytes read
1262507df40eSChuck Lever * @eof: OUT: set non-zero if operation reached the end of the file
1263507df40eSChuck Lever *
1264507df40eSChuck Lever * The caller must verify that there is enough space in @rqstp.rq_res
1265507df40eSChuck Lever * to perform this operation.
1266507df40eSChuck Lever *
1267dc97618dSJ. Bruce Fields * N.B. After this call fhp needs an fh_put
1268507df40eSChuck Lever *
1269507df40eSChuck Lever * Returns nfs_ok on success, otherwise an nfserr stat value is
1270507df40eSChuck Lever * returned.
1271dc97618dSJ. Bruce Fields */
nfsd_read(struct svc_rqst * rqstp,struct svc_fh * fhp,loff_t offset,unsigned long * count,u32 * eof)1272dc97618dSJ. Bruce Fields __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
1273507df40eSChuck Lever loff_t offset, unsigned long *count, u32 *eof)
1274dc97618dSJ. Bruce Fields {
127548cd7b51SJeff Layton struct nfsd_file *nf;
1276dc97618dSJ. Bruce Fields struct file *file;
1277dc97618dSJ. Bruce Fields __be32 err;
1278dc97618dSJ. Bruce Fields
1279f394b62bSChuck Lever trace_nfsd_read_start(rqstp, fhp, offset, *count);
12804d1ea845SChuck Lever err = nfsd_file_acquire_gc(rqstp, fhp, NFSD_MAY_READ, &nf);
1281dc97618dSJ. Bruce Fields if (err)
1282dc97618dSJ. Bruce Fields return err;
1283dc97618dSJ. Bruce Fields
128448cd7b51SJeff Layton file = nf->nf_file;
1285c21fd7a8SChuck Lever if (file->f_op->splice_read && nfsd_read_splice_ok(rqstp))
128683a63072STrond Myklebust err = nfsd_splice_read(rqstp, fhp, file, offset, count, eof);
1287a4058c5bSChristoph Hellwig else
1288507df40eSChuck Lever err = nfsd_iter_read(rqstp, fhp, file, offset, count, 0, eof);
12896e8b50d1SJeff Layton
129048cd7b51SJeff Layton nfsd_file_put(nf);
1291f394b62bSChuck Lever trace_nfsd_read_done(rqstp, fhp, offset, *count);
1292fa0a2126SJ. Bruce Fields return err;
1293fa0a2126SJ. Bruce Fields }
1294fa0a2126SJ. Bruce Fields
12951da177e4SLinus Torvalds /*
12961da177e4SLinus Torvalds * Write data to a file.
12971da177e4SLinus Torvalds * The stable flag requests synchronous writes.
12981da177e4SLinus Torvalds * N.B. After this call fhp needs an fh_put
12991da177e4SLinus Torvalds */
13006264d69dSAl Viro __be32
nfsd_write(struct svc_rqst * rqstp,struct svc_fh * fhp,loff_t offset,struct kvec * vec,int vlen,unsigned long * cnt,int stable,__be32 * verf)130152e380e0SKinglong Mee nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset,
130219e0663fSTrond Myklebust struct kvec *vec, int vlen, unsigned long *cnt, int stable,
130319e0663fSTrond Myklebust __be32 *verf)
13041da177e4SLinus Torvalds {
1305b4935239SJeff Layton struct nfsd_file *nf;
1306b4935239SJeff Layton __be32 err;
13071da177e4SLinus Torvalds
1308f394b62bSChuck Lever trace_nfsd_write_start(rqstp, fhp, offset, *cnt);
13096e8b50d1SJeff Layton
13104d1ea845SChuck Lever err = nfsd_file_acquire_gc(rqstp, fhp, NFSD_MAY_WRITE, &nf);
13111da177e4SLinus Torvalds if (err)
13121da177e4SLinus Torvalds goto out;
13131da177e4SLinus Torvalds
131416f8f894STrond Myklebust err = nfsd_vfs_write(rqstp, fhp, nf, offset, vec,
131519e0663fSTrond Myklebust vlen, cnt, stable, verf);
1316b4935239SJeff Layton nfsd_file_put(nf);
13171da177e4SLinus Torvalds out:
1318f394b62bSChuck Lever trace_nfsd_write_done(rqstp, fhp, offset, *cnt);
13191da177e4SLinus Torvalds return err;
13201da177e4SLinus Torvalds }
13211da177e4SLinus Torvalds
13223f965021SChuck Lever /**
13233f965021SChuck Lever * nfsd_commit - Commit pending writes to stable storage
13243f965021SChuck Lever * @rqstp: RPC request being processed
13253f965021SChuck Lever * @fhp: NFS filehandle
1326c2528490SChuck Lever * @nf: target file
13273f965021SChuck Lever * @offset: raw offset from beginning of file
13283f965021SChuck Lever * @count: raw count of bytes to sync
13293f965021SChuck Lever * @verf: filled in with the server's current write verifier
1330aa696a6fSTrond Myklebust *
13313f965021SChuck Lever * Note: we guarantee that data that lies within the range specified
13323f965021SChuck Lever * by the 'offset' and 'count' parameters will be synced. The server
13333f965021SChuck Lever * is permitted to sync data that lies outside this range at the
13343f965021SChuck Lever * same time.
13351da177e4SLinus Torvalds *
13361da177e4SLinus Torvalds * Unfortunately we cannot lock the file to make sure we return full WCC
13371da177e4SLinus Torvalds * data to the client, as locking happens lower down in the filesystem.
13383f965021SChuck Lever *
13393f965021SChuck Lever * Return values:
13403f965021SChuck Lever * An nfsstat value in network byte order.
13411da177e4SLinus Torvalds */
13426264d69dSAl Viro __be32
nfsd_commit(struct svc_rqst * rqstp,struct svc_fh * fhp,struct nfsd_file * nf,u64 offset,u32 count,__be32 * verf)1343c2528490SChuck Lever nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf,
1344c2528490SChuck Lever u64 offset, u32 count, __be32 *verf)
13451da177e4SLinus Torvalds {
1346c2528490SChuck Lever __be32 err = nfs_ok;
13473f965021SChuck Lever u64 maxbytes;
13483f965021SChuck Lever loff_t start, end;
13492c445a0eSChuck Lever struct nfsd_net *nn;
13503f965021SChuck Lever
13513f965021SChuck Lever /*
13523f965021SChuck Lever * Convert the client-provided (offset, count) range to a
13533f965021SChuck Lever * (start, end) range. If the client-provided range falls
13543f965021SChuck Lever * outside the maximum file size of the underlying FS,
13553f965021SChuck Lever * clamp the sync range appropriately.
13563f965021SChuck Lever */
13573f965021SChuck Lever start = 0;
13583f965021SChuck Lever end = LLONG_MAX;
13593f965021SChuck Lever maxbytes = (u64)fhp->fh_dentry->d_sb->s_maxbytes;
13603f965021SChuck Lever if (offset < maxbytes) {
13613f965021SChuck Lever start = offset;
13623f965021SChuck Lever if (count && (offset + count - 1 < maxbytes))
13633f965021SChuck Lever end = offset + count - 1;
13643f965021SChuck Lever }
13653f965021SChuck Lever
13662c445a0eSChuck Lever nn = net_generic(nf->nf_net, nfsd_net_id);
13671da177e4SLinus Torvalds if (EX_ISSYNC(fhp->fh_export)) {
1368555dbf1aSTrond Myklebust errseq_t since = READ_ONCE(nf->nf_file->f_wb_err);
1369555dbf1aSTrond Myklebust int err2;
1370aa696a6fSTrond Myklebust
13713f965021SChuck Lever err2 = vfs_fsync_range(nf->nf_file, start, end, 0);
1372bbf2f098STrond Myklebust switch (err2) {
1373bbf2f098STrond Myklebust case 0:
13743988a578SChuck Lever nfsd_copy_write_verifier(verf, nn);
1375555dbf1aSTrond Myklebust err2 = filemap_check_wb_err(nf->nf_file->f_mapping,
1376555dbf1aSTrond Myklebust since);
13778a9ffb8cSAlexey Khoroshilov err = nfserrno(err2);
1378bbf2f098STrond Myklebust break;
1379bbf2f098STrond Myklebust case -EINVAL:
13801da177e4SLinus Torvalds err = nfserr_notsupp;
1381bbf2f098STrond Myklebust break;
1382bbf2f098STrond Myklebust default:
13831b2021bdSTrond Myklebust commit_reset_write_verifier(nn, rqstp, err2);
1384555dbf1aSTrond Myklebust err = nfserrno(err2);
13858a9ffb8cSAlexey Khoroshilov }
1386524ff1afSTrond Myklebust } else
13873988a578SChuck Lever nfsd_copy_write_verifier(verf, nn);
13881da177e4SLinus Torvalds
13891da177e4SLinus Torvalds return err;
13901da177e4SLinus Torvalds }
13911da177e4SLinus Torvalds
13925f46e950SChuck Lever /**
13935f46e950SChuck Lever * nfsd_create_setattr - Set a created file's attributes
13945f46e950SChuck Lever * @rqstp: RPC transaction being executed
13955f46e950SChuck Lever * @fhp: NFS filehandle of parent directory
13965f46e950SChuck Lever * @resfhp: NFS filehandle of new object
13977fe2a71dSNeilBrown * @attrs: requested attributes of new object
13985f46e950SChuck Lever *
13995f46e950SChuck Lever * Returns nfs_ok on success, or an nfsstat in network byte order.
14005f46e950SChuck Lever */
14015f46e950SChuck Lever __be32
nfsd_create_setattr(struct svc_rqst * rqstp,struct svc_fh * fhp,struct svc_fh * resfhp,struct nfsd_attrs * attrs)14025f46e950SChuck Lever nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp,
14037fe2a71dSNeilBrown struct svc_fh *resfhp, struct nfsd_attrs *attrs)
14045c002b3bSJ. Bruce Fields {
14057fe2a71dSNeilBrown struct iattr *iap = attrs->na_iattr;
14065f46e950SChuck Lever __be32 status;
14075f46e950SChuck Lever
14085c002b3bSJ. Bruce Fields /*
14095f46e950SChuck Lever * Mode has already been set by file creation.
14105c002b3bSJ. Bruce Fields */
14115c002b3bSJ. Bruce Fields iap->ia_valid &= ~ATTR_MODE;
14125f46e950SChuck Lever
14135c002b3bSJ. Bruce Fields /*
14145c002b3bSJ. Bruce Fields * Setting uid/gid works only for root. Irix appears to
14155c002b3bSJ. Bruce Fields * send along the gid on create when it tries to implement
14165c002b3bSJ. Bruce Fields * setgid directories via NFS:
14175c002b3bSJ. Bruce Fields */
14186fab8779SEric W. Biederman if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID))
14195c002b3bSJ. Bruce Fields iap->ia_valid &= ~(ATTR_UID|ATTR_GID);
14205f46e950SChuck Lever
14215f46e950SChuck Lever /*
14225f46e950SChuck Lever * Callers expect new file metadata to be committed even
14235f46e950SChuck Lever * if the attributes have not changed.
14245f46e950SChuck Lever */
1425*442d27ffSStephen Smalley if (nfsd_attrs_valid(attrs))
142624d92de9STrond Myklebust status = nfsd_setattr(rqstp, resfhp, attrs, NULL);
14275f46e950SChuck Lever else
14285f46e950SChuck Lever status = nfserrno(commit_metadata(resfhp));
14295f46e950SChuck Lever
14305f46e950SChuck Lever /*
14315f46e950SChuck Lever * Transactional filesystems had a chance to commit changes
14325f46e950SChuck Lever * for both parent and child simultaneously making the
14335f46e950SChuck Lever * following commit_metadata a noop in many cases.
14345f46e950SChuck Lever */
14355f46e950SChuck Lever if (!status)
14365f46e950SChuck Lever status = nfserrno(commit_metadata(fhp));
14375f46e950SChuck Lever
14385f46e950SChuck Lever /*
14395f46e950SChuck Lever * Update the new filehandle to pick up the new attributes.
14405f46e950SChuck Lever */
14415f46e950SChuck Lever if (!status)
14425f46e950SChuck Lever status = fh_update(resfhp);
14435f46e950SChuck Lever
14445f46e950SChuck Lever return status;
14455c002b3bSJ. Bruce Fields }
14465c002b3bSJ. Bruce Fields
14474ac35c2fSwengang wang /* HPUX client sometimes creates a file in mode 000, and sets size to 0.
14484ac35c2fSwengang wang * setting size to 0 may fail for some specific file systems by the permission
14494ac35c2fSwengang wang * checking which requires WRITE permission but the mode is 000.
14504ac35c2fSwengang wang * we ignore the resizing(to 0) on the just new created file, since the size is
14514ac35c2fSwengang wang * 0 after file created.
14524ac35c2fSwengang wang *
14534ac35c2fSwengang wang * call this only after vfs_create() is called.
14544ac35c2fSwengang wang * */
14554ac35c2fSwengang wang static void
nfsd_check_ignore_resizing(struct iattr * iap)14564ac35c2fSwengang wang nfsd_check_ignore_resizing(struct iattr *iap)
14574ac35c2fSwengang wang {
14584ac35c2fSwengang wang if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0))
14594ac35c2fSwengang wang iap->ia_valid &= ~ATTR_SIZE;
14604ac35c2fSwengang wang }
14614ac35c2fSwengang wang
1462b44061d0SJ. Bruce Fields /* The parent directory should already be locked: */
14636264d69dSAl Viro __be32
nfsd_create_locked(struct svc_rqst * rqstp,struct svc_fh * fhp,struct nfsd_attrs * attrs,int type,dev_t rdev,struct svc_fh * resfhp)1464b44061d0SJ. Bruce Fields nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
14659558f930SNeilBrown struct nfsd_attrs *attrs,
14661da177e4SLinus Torvalds int type, dev_t rdev, struct svc_fh *resfhp)
14671da177e4SLinus Torvalds {
14682b118859SDan Carpenter struct dentry *dentry, *dchild;
14691da177e4SLinus Torvalds struct inode *dirp;
14707fe2a71dSNeilBrown struct iattr *iap = attrs->na_iattr;
14716264d69dSAl Viro __be32 err;
14726264d69dSAl Viro int host_err;
14731da177e4SLinus Torvalds
14741da177e4SLinus Torvalds dentry = fhp->fh_dentry;
14752b0143b5SDavid Howells dirp = d_inode(dentry);
14761da177e4SLinus Torvalds
14771da177e4SLinus Torvalds dchild = dget(resfhp->fh_dentry);
14787eed34f1SOleg Drokin err = nfsd_permission(rqstp, fhp->fh_export, dentry, NFSD_MAY_CREATE);
14797eed34f1SOleg Drokin if (err)
14807eed34f1SOleg Drokin goto out;
14817eed34f1SOleg Drokin
14821da177e4SLinus Torvalds if (!(iap->ia_valid & ATTR_MODE))
14831da177e4SLinus Torvalds iap->ia_mode = 0;
14841da177e4SLinus Torvalds iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type;
14851da177e4SLinus Torvalds
148622cf8419SJ. Bruce Fields if (!IS_POSIXACL(dirp))
148722cf8419SJ. Bruce Fields iap->ia_mode &= ~current_umask();
148822cf8419SJ. Bruce Fields
1489088406bcSJ. Bruce Fields err = 0;
14901da177e4SLinus Torvalds switch (type) {
14911da177e4SLinus Torvalds case S_IFREG:
1492abf08576SChristian Brauner host_err = vfs_create(&nop_mnt_idmap, dirp, dchild,
1493abf08576SChristian Brauner iap->ia_mode, true);
14944ac35c2fSwengang wang if (!host_err)
14954ac35c2fSwengang wang nfsd_check_ignore_resizing(iap);
14961da177e4SLinus Torvalds break;
14971da177e4SLinus Torvalds case S_IFDIR:
1498abf08576SChristian Brauner host_err = vfs_mkdir(&nop_mnt_idmap, dirp, dchild, iap->ia_mode);
14993819bb0dSAl Viro if (!host_err && unlikely(d_unhashed(dchild))) {
15003819bb0dSAl Viro struct dentry *d;
15013819bb0dSAl Viro d = lookup_one_len(dchild->d_name.name,
15023819bb0dSAl Viro dchild->d_parent,
15033819bb0dSAl Viro dchild->d_name.len);
15043819bb0dSAl Viro if (IS_ERR(d)) {
15053819bb0dSAl Viro host_err = PTR_ERR(d);
15063819bb0dSAl Viro break;
15073819bb0dSAl Viro }
15083819bb0dSAl Viro if (unlikely(d_is_negative(d))) {
15093819bb0dSAl Viro dput(d);
15103819bb0dSAl Viro err = nfserr_serverfault;
15113819bb0dSAl Viro goto out;
15123819bb0dSAl Viro }
15133819bb0dSAl Viro dput(resfhp->fh_dentry);
15143819bb0dSAl Viro resfhp->fh_dentry = dget(d);
15153819bb0dSAl Viro err = fh_update(resfhp);
15163819bb0dSAl Viro dput(dchild);
15173819bb0dSAl Viro dchild = d;
15183819bb0dSAl Viro if (err)
15193819bb0dSAl Viro goto out;
15203819bb0dSAl Viro }
15211da177e4SLinus Torvalds break;
15221da177e4SLinus Torvalds case S_IFCHR:
15231da177e4SLinus Torvalds case S_IFBLK:
15241da177e4SLinus Torvalds case S_IFIFO:
15251da177e4SLinus Torvalds case S_IFSOCK:
1526abf08576SChristian Brauner host_err = vfs_mknod(&nop_mnt_idmap, dirp, dchild,
15276521f891SChristian Brauner iap->ia_mode, rdev);
15281da177e4SLinus Torvalds break;
152971423274SJ. Bruce Fields default:
153071423274SJ. Bruce Fields printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
153171423274SJ. Bruce Fields type);
153271423274SJ. Bruce Fields host_err = -EINVAL;
1533463c3197SDave Hansen }
15344a55c101SJan Kara if (host_err < 0)
1535463c3197SDave Hansen goto out_nfserr;
15361da177e4SLinus Torvalds
15377fe2a71dSNeilBrown err = nfsd_create_setattr(rqstp, fhp, resfhp, attrs);
15381da177e4SLinus Torvalds
15391da177e4SLinus Torvalds out:
15401da177e4SLinus Torvalds dput(dchild);
15411da177e4SLinus Torvalds return err;
15421da177e4SLinus Torvalds
15431da177e4SLinus Torvalds out_nfserr:
15446264d69dSAl Viro err = nfserrno(host_err);
15451da177e4SLinus Torvalds goto out;
15461da177e4SLinus Torvalds }
15471da177e4SLinus Torvalds
1548b44061d0SJ. Bruce Fields /*
1549b44061d0SJ. Bruce Fields * Create a filesystem object (regular, directory, special).
1550b44061d0SJ. Bruce Fields * Note that the parent directory is left locked.
1551b44061d0SJ. Bruce Fields *
1552b44061d0SJ. Bruce Fields * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp
1553b44061d0SJ. Bruce Fields */
1554b44061d0SJ. Bruce Fields __be32
nfsd_create(struct svc_rqst * rqstp,struct svc_fh * fhp,char * fname,int flen,struct nfsd_attrs * attrs,int type,dev_t rdev,struct svc_fh * resfhp)1555b44061d0SJ. Bruce Fields nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
15567fe2a71dSNeilBrown char *fname, int flen, struct nfsd_attrs *attrs,
1557b44061d0SJ. Bruce Fields int type, dev_t rdev, struct svc_fh *resfhp)
1558b44061d0SJ. Bruce Fields {
1559b44061d0SJ. Bruce Fields struct dentry *dentry, *dchild = NULL;
1560b44061d0SJ. Bruce Fields __be32 err;
1561b44061d0SJ. Bruce Fields int host_err;
1562b44061d0SJ. Bruce Fields
1563b44061d0SJ. Bruce Fields if (isdotent(fname, flen))
1564b44061d0SJ. Bruce Fields return nfserr_exist;
1565b44061d0SJ. Bruce Fields
1566fa08139dSJ. Bruce Fields err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_NOP);
1567b44061d0SJ. Bruce Fields if (err)
1568b44061d0SJ. Bruce Fields return err;
1569b44061d0SJ. Bruce Fields
1570b44061d0SJ. Bruce Fields dentry = fhp->fh_dentry;
1571b44061d0SJ. Bruce Fields
1572b44061d0SJ. Bruce Fields host_err = fh_want_write(fhp);
1573b44061d0SJ. Bruce Fields if (host_err)
1574b44061d0SJ. Bruce Fields return nfserrno(host_err);
1575b44061d0SJ. Bruce Fields
1576debf16f0SNeilBrown inode_lock_nested(dentry->d_inode, I_MUTEX_PARENT);
1577b44061d0SJ. Bruce Fields dchild = lookup_one_len(fname, dentry, flen);
1578b44061d0SJ. Bruce Fields host_err = PTR_ERR(dchild);
1579927bfc56SNeilBrown if (IS_ERR(dchild)) {
1580927bfc56SNeilBrown err = nfserrno(host_err);
1581927bfc56SNeilBrown goto out_unlock;
1582927bfc56SNeilBrown }
1583b44061d0SJ. Bruce Fields err = fh_compose(resfhp, fhp->fh_export, dchild, fhp);
1584502aa0a5SJosef Bacik /*
1585502aa0a5SJosef Bacik * We unconditionally drop our ref to dchild as fh_compose will have
1586502aa0a5SJosef Bacik * already grabbed its own ref for it.
1587502aa0a5SJosef Bacik */
1588b44061d0SJ. Bruce Fields dput(dchild);
1589502aa0a5SJosef Bacik if (err)
1590927bfc56SNeilBrown goto out_unlock;
1591a332018aSJeff Layton err = fh_fill_pre_attrs(fhp);
1592a332018aSJeff Layton if (err != nfs_ok)
1593a332018aSJeff Layton goto out_unlock;
15949558f930SNeilBrown err = nfsd_create_locked(rqstp, fhp, attrs, type, rdev, resfhp);
1595debf16f0SNeilBrown fh_fill_post_attrs(fhp);
1596927bfc56SNeilBrown out_unlock:
1597debf16f0SNeilBrown inode_unlock(dentry->d_inode);
1598927bfc56SNeilBrown return err;
1599b44061d0SJ. Bruce Fields }
1600b44061d0SJ. Bruce Fields
16011da177e4SLinus Torvalds /*
16021da177e4SLinus Torvalds * Read a symlink. On entry, *lenp must contain the maximum path length that
16031da177e4SLinus Torvalds * fits into the buffer. On return, it contains the true length.
16041da177e4SLinus Torvalds * N.B. After this call fhp needs an fh_put
16051da177e4SLinus Torvalds */
16066264d69dSAl Viro __be32
nfsd_readlink(struct svc_rqst * rqstp,struct svc_fh * fhp,char * buf,int * lenp)16071da177e4SLinus Torvalds nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp)
16081da177e4SLinus Torvalds {
16096264d69dSAl Viro __be32 err;
16104d7edbc3SAl Viro const char *link;
161168ac1234SAl Viro struct path path;
16124d7edbc3SAl Viro DEFINE_DELAYED_CALL(done);
16134d7edbc3SAl Viro int len;
16141da177e4SLinus Torvalds
16158837abcaSMiklos Szeredi err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP);
16164d7edbc3SAl Viro if (unlikely(err))
16174d7edbc3SAl Viro return err;
16181da177e4SLinus Torvalds
161968ac1234SAl Viro path.mnt = fhp->fh_export->ex_path.mnt;
162068ac1234SAl Viro path.dentry = fhp->fh_dentry;
16211da177e4SLinus Torvalds
16224d7edbc3SAl Viro if (unlikely(!d_is_symlink(path.dentry)))
16234d7edbc3SAl Viro return nfserr_inval;
16241da177e4SLinus Torvalds
162568ac1234SAl Viro touch_atime(&path);
16261da177e4SLinus Torvalds
16274d7edbc3SAl Viro link = vfs_get_link(path.dentry, &done);
16284d7edbc3SAl Viro if (IS_ERR(link))
16294d7edbc3SAl Viro return nfserrno(PTR_ERR(link));
16301da177e4SLinus Torvalds
16314d7edbc3SAl Viro len = strlen(link);
16324d7edbc3SAl Viro if (len < *lenp)
16334d7edbc3SAl Viro *lenp = len;
16344d7edbc3SAl Viro memcpy(buf, link, *lenp);
16354d7edbc3SAl Viro do_delayed_call(&done);
16364d7edbc3SAl Viro return 0;
16371da177e4SLinus Torvalds }
16381da177e4SLinus Torvalds
163993adc1e3SNeilBrown /**
164093adc1e3SNeilBrown * nfsd_symlink - Create a symlink and look up its inode
164193adc1e3SNeilBrown * @rqstp: RPC transaction being executed
164293adc1e3SNeilBrown * @fhp: NFS filehandle of parent directory
164393adc1e3SNeilBrown * @fname: filename of the new symlink
164493adc1e3SNeilBrown * @flen: length of @fname
164593adc1e3SNeilBrown * @path: content of the new symlink (NUL-terminated)
164693adc1e3SNeilBrown * @attrs: requested attributes of new object
164793adc1e3SNeilBrown * @resfhp: NFS filehandle of new object
164893adc1e3SNeilBrown *
16491da177e4SLinus Torvalds * N.B. After this call _both_ fhp and resfhp need an fh_put
165093adc1e3SNeilBrown *
165193adc1e3SNeilBrown * Returns nfs_ok on success, or an nfsstat in network byte order.
16521da177e4SLinus Torvalds */
16536264d69dSAl Viro __be32
nfsd_symlink(struct svc_rqst * rqstp,struct svc_fh * fhp,char * fname,int flen,char * path,struct nfsd_attrs * attrs,struct svc_fh * resfhp)16541da177e4SLinus Torvalds nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
16551da177e4SLinus Torvalds char *fname, int flen,
165693adc1e3SNeilBrown char *path, struct nfsd_attrs *attrs,
16571e444f5bSKinglong Mee struct svc_fh *resfhp)
16581da177e4SLinus Torvalds {
16591da177e4SLinus Torvalds struct dentry *dentry, *dnew;
16606264d69dSAl Viro __be32 err, cerr;
16616264d69dSAl Viro int host_err;
16621da177e4SLinus Torvalds
16631da177e4SLinus Torvalds err = nfserr_noent;
166452ee0433SJ. Bruce Fields if (!flen || path[0] == '\0')
16651da177e4SLinus Torvalds goto out;
16661da177e4SLinus Torvalds err = nfserr_exist;
16671da177e4SLinus Torvalds if (isdotent(fname, flen))
16681da177e4SLinus Torvalds goto out;
16691da177e4SLinus Torvalds
16708837abcaSMiklos Szeredi err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE);
16711da177e4SLinus Torvalds if (err)
16721da177e4SLinus Torvalds goto out;
16734a55c101SJan Kara
16744a55c101SJan Kara host_err = fh_want_write(fhp);
1675927bfc56SNeilBrown if (host_err) {
1676927bfc56SNeilBrown err = nfserrno(host_err);
1677927bfc56SNeilBrown goto out;
1678927bfc56SNeilBrown }
16794a55c101SJan Kara
16801da177e4SLinus Torvalds dentry = fhp->fh_dentry;
1681debf16f0SNeilBrown inode_lock_nested(dentry->d_inode, I_MUTEX_PARENT);
16821da177e4SLinus Torvalds dnew = lookup_one_len(fname, dentry, flen);
1683927bfc56SNeilBrown if (IS_ERR(dnew)) {
1684927bfc56SNeilBrown err = nfserrno(PTR_ERR(dnew));
1685debf16f0SNeilBrown inode_unlock(dentry->d_inode);
1686927bfc56SNeilBrown goto out_drop_write;
1687927bfc56SNeilBrown }
1688a332018aSJeff Layton err = fh_fill_pre_attrs(fhp);
1689a332018aSJeff Layton if (err != nfs_ok)
1690a332018aSJeff Layton goto out_unlock;
1691abf08576SChristian Brauner host_err = vfs_symlink(&nop_mnt_idmap, d_inode(dentry), dnew, path);
16926264d69dSAl Viro err = nfserrno(host_err);
169393adc1e3SNeilBrown cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp);
169493adc1e3SNeilBrown if (!err)
169593adc1e3SNeilBrown nfsd_create_setattr(rqstp, fhp, resfhp, attrs);
1696debf16f0SNeilBrown fh_fill_post_attrs(fhp);
1697a332018aSJeff Layton out_unlock:
1698debf16f0SNeilBrown inode_unlock(dentry->d_inode);
1699f501912aSBen Myers if (!err)
1700f501912aSBen Myers err = nfserrno(commit_metadata(fhp));
17011da177e4SLinus Torvalds dput(dnew);
17021da177e4SLinus Torvalds if (err==0) err = cerr;
1703927bfc56SNeilBrown out_drop_write:
1704927bfc56SNeilBrown fh_drop_write(fhp);
17051da177e4SLinus Torvalds out:
17061da177e4SLinus Torvalds return err;
17071da177e4SLinus Torvalds }
17081da177e4SLinus Torvalds
17091da177e4SLinus Torvalds /*
17101da177e4SLinus Torvalds * Create a hardlink
17111da177e4SLinus Torvalds * N.B. After this call _both_ ffhp and tfhp need an fh_put
17121da177e4SLinus Torvalds */
17136264d69dSAl Viro __be32
nfsd_link(struct svc_rqst * rqstp,struct svc_fh * ffhp,char * name,int len,struct svc_fh * tfhp)17141da177e4SLinus Torvalds nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
17151da177e4SLinus Torvalds char *name, int len, struct svc_fh *tfhp)
17161da177e4SLinus Torvalds {
17171da177e4SLinus Torvalds struct dentry *ddir, *dnew, *dold;
171855b13354SJ. Bruce Fields struct inode *dirp;
17196264d69dSAl Viro __be32 err;
17206264d69dSAl Viro int host_err;
17211da177e4SLinus Torvalds
17228837abcaSMiklos Szeredi err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
17231da177e4SLinus Torvalds if (err)
17241da177e4SLinus Torvalds goto out;
17257d818a7bSJ. Bruce Fields err = fh_verify(rqstp, tfhp, 0, NFSD_MAY_NOP);
17261da177e4SLinus Torvalds if (err)
17271da177e4SLinus Torvalds goto out;
17287d818a7bSJ. Bruce Fields err = nfserr_isdir;
1729e36cb0b8SDavid Howells if (d_is_dir(tfhp->fh_dentry))
17307d818a7bSJ. Bruce Fields goto out;
17311da177e4SLinus Torvalds err = nfserr_perm;
17321da177e4SLinus Torvalds if (!len)
17331da177e4SLinus Torvalds goto out;
17341da177e4SLinus Torvalds err = nfserr_exist;
17351da177e4SLinus Torvalds if (isdotent(name, len))
17361da177e4SLinus Torvalds goto out;
17371da177e4SLinus Torvalds
17384a55c101SJan Kara host_err = fh_want_write(tfhp);
17394a55c101SJan Kara if (host_err) {
17404a55c101SJan Kara err = nfserrno(host_err);
17414a55c101SJan Kara goto out;
17424a55c101SJan Kara }
17434a55c101SJan Kara
17441da177e4SLinus Torvalds ddir = ffhp->fh_dentry;
17452b0143b5SDavid Howells dirp = d_inode(ddir);
1746debf16f0SNeilBrown inode_lock_nested(dirp, I_MUTEX_PARENT);
17471da177e4SLinus Torvalds
17481da177e4SLinus Torvalds dnew = lookup_one_len(name, ddir, len);
1749e18bcb33SNeilBrown if (IS_ERR(dnew)) {
1750e18bcb33SNeilBrown err = nfserrno(PTR_ERR(dnew));
1751e18bcb33SNeilBrown goto out_unlock;
1752e18bcb33SNeilBrown }
17531da177e4SLinus Torvalds
17541da177e4SLinus Torvalds dold = tfhp->fh_dentry;
17551da177e4SLinus Torvalds
17564795bb37SJ. Bruce Fields err = nfserr_noent;
17572b0143b5SDavid Howells if (d_really_is_negative(dold))
17584a55c101SJan Kara goto out_dput;
1759a332018aSJeff Layton err = fh_fill_pre_attrs(ffhp);
1760a332018aSJeff Layton if (err != nfs_ok)
1761a332018aSJeff Layton goto out_dput;
1762abf08576SChristian Brauner host_err = vfs_link(dold, &nop_mnt_idmap, dirp, dnew, NULL);
1763debf16f0SNeilBrown fh_fill_post_attrs(ffhp);
1764debf16f0SNeilBrown inode_unlock(dirp);
17656264d69dSAl Viro if (!host_err) {
1766f501912aSBen Myers err = nfserrno(commit_metadata(ffhp));
1767f501912aSBen Myers if (!err)
1768f501912aSBen Myers err = nfserrno(commit_metadata(tfhp));
17691da177e4SLinus Torvalds } else {
17706264d69dSAl Viro if (host_err == -EXDEV && rqstp->rq_vers == 2)
17711da177e4SLinus Torvalds err = nfserr_acces;
17721da177e4SLinus Torvalds else
17736264d69dSAl Viro err = nfserrno(host_err);
17741da177e4SLinus Torvalds }
17751da177e4SLinus Torvalds dput(dnew);
1776e18bcb33SNeilBrown out_drop_write:
17774a55c101SJan Kara fh_drop_write(tfhp);
17781da177e4SLinus Torvalds out:
17791da177e4SLinus Torvalds return err;
17801da177e4SLinus Torvalds
1781e18bcb33SNeilBrown out_dput:
1782e18bcb33SNeilBrown dput(dnew);
1783e18bcb33SNeilBrown out_unlock:
1784debf16f0SNeilBrown inode_unlock(dirp);
1785e18bcb33SNeilBrown goto out_drop_write;
17861da177e4SLinus Torvalds }
17871da177e4SLinus Torvalds
17887775ec57SJeff Layton static void
nfsd_close_cached_files(struct dentry * dentry)17897775ec57SJeff Layton nfsd_close_cached_files(struct dentry *dentry)
17907775ec57SJeff Layton {
17917775ec57SJeff Layton struct inode *inode = d_inode(dentry);
17927775ec57SJeff Layton
17937775ec57SJeff Layton if (inode && S_ISREG(inode->i_mode))
17947775ec57SJeff Layton nfsd_file_close_inode_sync(inode);
17957775ec57SJeff Layton }
17967775ec57SJeff Layton
17977775ec57SJeff Layton static bool
nfsd_has_cached_files(struct dentry * dentry)17987775ec57SJeff Layton nfsd_has_cached_files(struct dentry *dentry)
17997775ec57SJeff Layton {
18007775ec57SJeff Layton bool ret = false;
18017775ec57SJeff Layton struct inode *inode = d_inode(dentry);
18027775ec57SJeff Layton
18037775ec57SJeff Layton if (inode && S_ISREG(inode->i_mode))
18047775ec57SJeff Layton ret = nfsd_file_is_cached(inode);
18057775ec57SJeff Layton return ret;
18067775ec57SJeff Layton }
18077775ec57SJeff Layton
18081da177e4SLinus Torvalds /*
18091da177e4SLinus Torvalds * Rename a file
18101da177e4SLinus Torvalds * N.B. After this call _both_ ffhp and tfhp need an fh_put
18111da177e4SLinus Torvalds */
18126264d69dSAl Viro __be32
nfsd_rename(struct svc_rqst * rqstp,struct svc_fh * ffhp,char * fname,int flen,struct svc_fh * tfhp,char * tname,int tlen)18131da177e4SLinus Torvalds nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
18141da177e4SLinus Torvalds struct svc_fh *tfhp, char *tname, int tlen)
18151da177e4SLinus Torvalds {
18161da177e4SLinus Torvalds struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap;
18171da177e4SLinus Torvalds struct inode *fdir, *tdir;
18186264d69dSAl Viro __be32 err;
18196264d69dSAl Viro int host_err;
18207f84b488SJeff Layton bool close_cached = false;
18211da177e4SLinus Torvalds
18228837abcaSMiklos Szeredi err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
18231da177e4SLinus Torvalds if (err)
18241da177e4SLinus Torvalds goto out;
18258837abcaSMiklos Szeredi err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE);
18261da177e4SLinus Torvalds if (err)
18271da177e4SLinus Torvalds goto out;
18281da177e4SLinus Torvalds
18291da177e4SLinus Torvalds fdentry = ffhp->fh_dentry;
18302b0143b5SDavid Howells fdir = d_inode(fdentry);
18311da177e4SLinus Torvalds
18321da177e4SLinus Torvalds tdentry = tfhp->fh_dentry;
18332b0143b5SDavid Howells tdir = d_inode(tdentry);
18341da177e4SLinus Torvalds
18351da177e4SLinus Torvalds err = nfserr_perm;
18361da177e4SLinus Torvalds if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen))
18371da177e4SLinus Torvalds goto out;
18381da177e4SLinus Torvalds
18391aee9158SAl Viro err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
18401aee9158SAl Viro if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt)
18411aee9158SAl Viro goto out;
18421aee9158SAl Viro if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry)
18431aee9158SAl Viro goto out;
18441aee9158SAl Viro
18457775ec57SJeff Layton retry:
18464a55c101SJan Kara host_err = fh_want_write(ffhp);
18474a55c101SJan Kara if (host_err) {
18484a55c101SJan Kara err = nfserrno(host_err);
18494a55c101SJan Kara goto out;
18504a55c101SJan Kara }
18514a55c101SJan Kara
18521da177e4SLinus Torvalds trap = lock_rename(tdentry, fdentry);
1853a8b00268SAl Viro if (IS_ERR(trap)) {
1854a8b00268SAl Viro err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev;
18559fe6e9e7SJan Kara goto out_want_write;
1856a8b00268SAl Viro }
1857a332018aSJeff Layton err = fh_fill_pre_attrs(ffhp);
1858a332018aSJeff Layton if (err != nfs_ok)
1859a332018aSJeff Layton goto out_unlock;
1860a332018aSJeff Layton err = fh_fill_pre_attrs(tfhp);
1861a332018aSJeff Layton if (err != nfs_ok)
1862a332018aSJeff Layton goto out_unlock;
18631da177e4SLinus Torvalds
18641da177e4SLinus Torvalds odentry = lookup_one_len(fname, fdentry, flen);
18656264d69dSAl Viro host_err = PTR_ERR(odentry);
18661da177e4SLinus Torvalds if (IS_ERR(odentry))
18671da177e4SLinus Torvalds goto out_nfserr;
18681da177e4SLinus Torvalds
18696264d69dSAl Viro host_err = -ENOENT;
18702b0143b5SDavid Howells if (d_really_is_negative(odentry))
18711da177e4SLinus Torvalds goto out_dput_old;
18726264d69dSAl Viro host_err = -EINVAL;
18731da177e4SLinus Torvalds if (odentry == trap)
18741da177e4SLinus Torvalds goto out_dput_old;
18751da177e4SLinus Torvalds
18761da177e4SLinus Torvalds ndentry = lookup_one_len(tname, tdentry, tlen);
18776264d69dSAl Viro host_err = PTR_ERR(ndentry);
18781da177e4SLinus Torvalds if (IS_ERR(ndentry))
18791da177e4SLinus Torvalds goto out_dput_old;
18806264d69dSAl Viro host_err = -ENOTEMPTY;
18811da177e4SLinus Torvalds if (ndentry == trap)
18821da177e4SLinus Torvalds goto out_dput_new;
18831da177e4SLinus Torvalds
18847f84b488SJeff Layton if ((ndentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK) &&
18857f84b488SJeff Layton nfsd_has_cached_files(ndentry)) {
18867f84b488SJeff Layton close_cached = true;
18877775ec57SJeff Layton goto out_dput_old;
18887775ec57SJeff Layton } else {
18899fe61450SChristian Brauner struct renamedata rd = {
1890abf08576SChristian Brauner .old_mnt_idmap = &nop_mnt_idmap,
18919fe61450SChristian Brauner .old_dir = fdir,
18929fe61450SChristian Brauner .old_dentry = odentry,
1893abf08576SChristian Brauner .new_mnt_idmap = &nop_mnt_idmap,
18949fe61450SChristian Brauner .new_dir = tdir,
18959fe61450SChristian Brauner .new_dentry = ndentry,
18969fe61450SChristian Brauner };
189768c522afSChuck Lever int retries;
189868c522afSChuck Lever
189968c522afSChuck Lever for (retries = 1;;) {
19009fe61450SChristian Brauner host_err = vfs_rename(&rd);
190168c522afSChuck Lever if (host_err != -EAGAIN || !retries--)
190268c522afSChuck Lever break;
190368c522afSChuck Lever if (!nfsd_wait_for_delegreturn(rqstp, d_inode(odentry)))
190468c522afSChuck Lever break;
190568c522afSChuck Lever }
1906f501912aSBen Myers if (!host_err) {
1907f501912aSBen Myers host_err = commit_metadata(tfhp);
19086264d69dSAl Viro if (!host_err)
1909f501912aSBen Myers host_err = commit_metadata(ffhp);
19101da177e4SLinus Torvalds }
19117775ec57SJeff Layton }
19121da177e4SLinus Torvalds out_dput_new:
19131da177e4SLinus Torvalds dput(ndentry);
19141da177e4SLinus Torvalds out_dput_old:
19151da177e4SLinus Torvalds dput(odentry);
19161da177e4SLinus Torvalds out_nfserr:
19176264d69dSAl Viro err = nfserrno(host_err);
1918dd8dd403SNeilBrown
19197f84b488SJeff Layton if (!close_cached) {
1920fcb5e3faSChuck Lever fh_fill_post_attrs(ffhp);
1921fcb5e3faSChuck Lever fh_fill_post_attrs(tfhp);
19227775ec57SJeff Layton }
1923a332018aSJeff Layton out_unlock:
19241da177e4SLinus Torvalds unlock_rename(tdentry, fdentry);
19259fe6e9e7SJan Kara out_want_write:
19264a55c101SJan Kara fh_drop_write(ffhp);
19271da177e4SLinus Torvalds
19287775ec57SJeff Layton /*
19295ff318f6SNeilBrown * If the target dentry has cached open files, then we need to
19305ff318f6SNeilBrown * try to close them prior to doing the rename. Final fput
19315ff318f6SNeilBrown * shouldn't be done with locks held however, so we delay it
19325ff318f6SNeilBrown * until this point and then reattempt the whole shebang.
19337775ec57SJeff Layton */
19347f84b488SJeff Layton if (close_cached) {
19357f84b488SJeff Layton close_cached = false;
19367775ec57SJeff Layton nfsd_close_cached_files(ndentry);
19377775ec57SJeff Layton dput(ndentry);
19387775ec57SJeff Layton goto retry;
19397775ec57SJeff Layton }
19401da177e4SLinus Torvalds out:
19411da177e4SLinus Torvalds return err;
19421da177e4SLinus Torvalds }
19431da177e4SLinus Torvalds
19441da177e4SLinus Torvalds /*
19451da177e4SLinus Torvalds * Unlink a file or directory
19461da177e4SLinus Torvalds * N.B. After this call fhp needs an fh_put
19471da177e4SLinus Torvalds */
19486264d69dSAl Viro __be32
nfsd_unlink(struct svc_rqst * rqstp,struct svc_fh * fhp,int type,char * fname,int flen)19491da177e4SLinus Torvalds nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
19501da177e4SLinus Torvalds char *fname, int flen)
19511da177e4SLinus Torvalds {
19521da177e4SLinus Torvalds struct dentry *dentry, *rdentry;
19531da177e4SLinus Torvalds struct inode *dirp;
1954e5d74a2dSYu Hsiang Huang struct inode *rinode;
19556264d69dSAl Viro __be32 err;
19566264d69dSAl Viro int host_err;
19571da177e4SLinus Torvalds
19581da177e4SLinus Torvalds err = nfserr_acces;
19591da177e4SLinus Torvalds if (!flen || isdotent(fname, flen))
19601da177e4SLinus Torvalds goto out;
19618837abcaSMiklos Szeredi err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE);
19621da177e4SLinus Torvalds if (err)
19631da177e4SLinus Torvalds goto out;
19641da177e4SLinus Torvalds
19654a55c101SJan Kara host_err = fh_want_write(fhp);
19664a55c101SJan Kara if (host_err)
19674a55c101SJan Kara goto out_nfserr;
19684a55c101SJan Kara
19691da177e4SLinus Torvalds dentry = fhp->fh_dentry;
19702b0143b5SDavid Howells dirp = d_inode(dentry);
1971debf16f0SNeilBrown inode_lock_nested(dirp, I_MUTEX_PARENT);
19721da177e4SLinus Torvalds
19731da177e4SLinus Torvalds rdentry = lookup_one_len(fname, dentry, flen);
19746264d69dSAl Viro host_err = PTR_ERR(rdentry);
19751da177e4SLinus Torvalds if (IS_ERR(rdentry))
1976b677c0c6SNeilBrown goto out_unlock;
19771da177e4SLinus Torvalds
19782b0143b5SDavid Howells if (d_really_is_negative(rdentry)) {
19791da177e4SLinus Torvalds dput(rdentry);
19800ca0c9d7SJ. Bruce Fields host_err = -ENOENT;
1981b677c0c6SNeilBrown goto out_unlock;
19821da177e4SLinus Torvalds }
1983e5d74a2dSYu Hsiang Huang rinode = d_inode(rdentry);
1984a332018aSJeff Layton err = fh_fill_pre_attrs(fhp);
1985a332018aSJeff Layton if (err != nfs_ok)
1986a332018aSJeff Layton goto out_unlock;
19871da177e4SLinus Torvalds
1988a332018aSJeff Layton ihold(rinode);
19891da177e4SLinus Torvalds if (!type)
19902b0143b5SDavid Howells type = d_inode(rdentry)->i_mode & S_IFMT;
19911da177e4SLinus Torvalds
19927775ec57SJeff Layton if (type != S_IFDIR) {
19935f5f8b6dSChuck Lever int retries;
19945f5f8b6dSChuck Lever
19957f84b488SJeff Layton if (rdentry->d_sb->s_export_op->flags & EXPORT_OP_CLOSE_BEFORE_UNLINK)
19967775ec57SJeff Layton nfsd_close_cached_files(rdentry);
19975f5f8b6dSChuck Lever
19985f5f8b6dSChuck Lever for (retries = 1;;) {
1999abf08576SChristian Brauner host_err = vfs_unlink(&nop_mnt_idmap, dirp, rdentry, NULL);
20005f5f8b6dSChuck Lever if (host_err != -EAGAIN || !retries--)
20015f5f8b6dSChuck Lever break;
20025f5f8b6dSChuck Lever if (!nfsd_wait_for_delegreturn(rqstp, rinode))
20035f5f8b6dSChuck Lever break;
20045f5f8b6dSChuck Lever }
20057775ec57SJeff Layton } else {
2006abf08576SChristian Brauner host_err = vfs_rmdir(&nop_mnt_idmap, dirp, rdentry);
20077775ec57SJeff Layton }
2008debf16f0SNeilBrown fh_fill_post_attrs(fhp);
20097775ec57SJeff Layton
2010debf16f0SNeilBrown inode_unlock(dirp);
2011541ce98cSJ. Bruce Fields if (!host_err)
2012541ce98cSJ. Bruce Fields host_err = commit_metadata(fhp);
20131da177e4SLinus Torvalds dput(rdentry);
2014e5d74a2dSYu Hsiang Huang iput(rinode); /* truncate the inode here */
20151da177e4SLinus Torvalds
20160ca0c9d7SJ. Bruce Fields out_drop_write:
20170ca0c9d7SJ. Bruce Fields fh_drop_write(fhp);
20181da177e4SLinus Torvalds out_nfserr:
2019466e16f0SNeilBrown if (host_err == -EBUSY) {
2020466e16f0SNeilBrown /* name is mounted-on. There is no perfect
2021466e16f0SNeilBrown * error status.
2022466e16f0SNeilBrown */
2023466e16f0SNeilBrown if (nfsd_v4client(rqstp))
2024466e16f0SNeilBrown err = nfserr_file_open;
2025466e16f0SNeilBrown else
2026466e16f0SNeilBrown err = nfserr_acces;
2027466e16f0SNeilBrown } else {
20286264d69dSAl Viro err = nfserrno(host_err);
2029466e16f0SNeilBrown }
2030f193fbabSYAMAMOTO Takashi out:
2031f193fbabSYAMAMOTO Takashi return err;
2032b677c0c6SNeilBrown out_unlock:
2033debf16f0SNeilBrown inode_unlock(dirp);
2034b677c0c6SNeilBrown goto out_drop_write;
20351da177e4SLinus Torvalds }
20361da177e4SLinus Torvalds
20371da177e4SLinus Torvalds /*
203814f7dd63SDavid Woodhouse * We do this buffering because we must not call back into the file
203914f7dd63SDavid Woodhouse * system's ->lookup() method from the filldir callback. That may well
204014f7dd63SDavid Woodhouse * deadlock a number of file systems.
204114f7dd63SDavid Woodhouse *
204214f7dd63SDavid Woodhouse * This is based heavily on the implementation of same in XFS.
204314f7dd63SDavid Woodhouse */
204414f7dd63SDavid Woodhouse struct buffered_dirent {
204514f7dd63SDavid Woodhouse u64 ino;
204614f7dd63SDavid Woodhouse loff_t offset;
204714f7dd63SDavid Woodhouse int namlen;
204814f7dd63SDavid Woodhouse unsigned int d_type;
204914f7dd63SDavid Woodhouse char name[];
205014f7dd63SDavid Woodhouse };
205114f7dd63SDavid Woodhouse
205214f7dd63SDavid Woodhouse struct readdir_data {
20535c0ba4e0SAl Viro struct dir_context ctx;
205414f7dd63SDavid Woodhouse char *dirent;
205514f7dd63SDavid Woodhouse size_t used;
205653c9c5c0SAl Viro int full;
205714f7dd63SDavid Woodhouse };
205814f7dd63SDavid Woodhouse
nfsd_buffered_filldir(struct dir_context * ctx,const char * name,int namlen,loff_t offset,u64 ino,unsigned int d_type)205925885a35SAl Viro static bool nfsd_buffered_filldir(struct dir_context *ctx, const char *name,
2060ac7576f4SMiklos Szeredi int namlen, loff_t offset, u64 ino,
2061ac7576f4SMiklos Szeredi unsigned int d_type)
206214f7dd63SDavid Woodhouse {
2063ac7576f4SMiklos Szeredi struct readdir_data *buf =
2064ac7576f4SMiklos Szeredi container_of(ctx, struct readdir_data, ctx);
206514f7dd63SDavid Woodhouse struct buffered_dirent *de = (void *)(buf->dirent + buf->used);
206614f7dd63SDavid Woodhouse unsigned int reclen;
206714f7dd63SDavid Woodhouse
206814f7dd63SDavid Woodhouse reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64));
206953c9c5c0SAl Viro if (buf->used + reclen > PAGE_SIZE) {
207053c9c5c0SAl Viro buf->full = 1;
207125885a35SAl Viro return false;
207253c9c5c0SAl Viro }
207314f7dd63SDavid Woodhouse
207414f7dd63SDavid Woodhouse de->namlen = namlen;
207514f7dd63SDavid Woodhouse de->offset = offset;
207614f7dd63SDavid Woodhouse de->ino = ino;
207714f7dd63SDavid Woodhouse de->d_type = d_type;
207814f7dd63SDavid Woodhouse memcpy(de->name, name, namlen);
207914f7dd63SDavid Woodhouse buf->used += reclen;
208014f7dd63SDavid Woodhouse
208125885a35SAl Viro return true;
208214f7dd63SDavid Woodhouse }
208314f7dd63SDavid Woodhouse
nfsd_buffered_readdir(struct file * file,struct svc_fh * fhp,nfsd_filldir_t func,struct readdir_cd * cdp,loff_t * offsetp)20846019ce07SChuck Lever static __be32 nfsd_buffered_readdir(struct file *file, struct svc_fh *fhp,
20856019ce07SChuck Lever nfsd_filldir_t func, struct readdir_cd *cdp,
20866019ce07SChuck Lever loff_t *offsetp)
20872628b766SDavid Woodhouse {
208814f7dd63SDavid Woodhouse struct buffered_dirent *de;
20892628b766SDavid Woodhouse int host_err;
209014f7dd63SDavid Woodhouse int size;
209114f7dd63SDavid Woodhouse loff_t offset;
2092ac6614b7SAl Viro struct readdir_data buf = {
2093ac6614b7SAl Viro .ctx.actor = nfsd_buffered_filldir,
2094ac6614b7SAl Viro .dirent = (void *)__get_free_page(GFP_KERNEL)
2095ac6614b7SAl Viro };
20962628b766SDavid Woodhouse
209714f7dd63SDavid Woodhouse if (!buf.dirent)
20982f9092e1SDavid Woodhouse return nfserrno(-ENOMEM);
209914f7dd63SDavid Woodhouse
210014f7dd63SDavid Woodhouse offset = *offsetp;
21012628b766SDavid Woodhouse
210214f7dd63SDavid Woodhouse while (1) {
210314f7dd63SDavid Woodhouse unsigned int reclen;
210414f7dd63SDavid Woodhouse
2105b726e923SDoug Nazar cdp->err = nfserr_eof; /* will be cleared on successful read */
210614f7dd63SDavid Woodhouse buf.used = 0;
210753c9c5c0SAl Viro buf.full = 0;
210814f7dd63SDavid Woodhouse
21095c0ba4e0SAl Viro host_err = iterate_dir(file, &buf.ctx);
211053c9c5c0SAl Viro if (buf.full)
211153c9c5c0SAl Viro host_err = 0;
211253c9c5c0SAl Viro
211353c9c5c0SAl Viro if (host_err < 0)
211414f7dd63SDavid Woodhouse break;
211514f7dd63SDavid Woodhouse
211614f7dd63SDavid Woodhouse size = buf.used;
211714f7dd63SDavid Woodhouse
211814f7dd63SDavid Woodhouse if (!size)
211914f7dd63SDavid Woodhouse break;
212014f7dd63SDavid Woodhouse
212114f7dd63SDavid Woodhouse de = (struct buffered_dirent *)buf.dirent;
212214f7dd63SDavid Woodhouse while (size > 0) {
212314f7dd63SDavid Woodhouse offset = de->offset;
212414f7dd63SDavid Woodhouse
212514f7dd63SDavid Woodhouse if (func(cdp, de->name, de->namlen, de->offset,
212614f7dd63SDavid Woodhouse de->ino, de->d_type))
21272f9092e1SDavid Woodhouse break;
212814f7dd63SDavid Woodhouse
212914f7dd63SDavid Woodhouse if (cdp->err != nfs_ok)
21302f9092e1SDavid Woodhouse break;
213114f7dd63SDavid Woodhouse
21326019ce07SChuck Lever trace_nfsd_dirent(fhp, de->ino, de->name, de->namlen);
21336019ce07SChuck Lever
213414f7dd63SDavid Woodhouse reclen = ALIGN(sizeof(*de) + de->namlen,
213514f7dd63SDavid Woodhouse sizeof(u64));
213614f7dd63SDavid Woodhouse size -= reclen;
213714f7dd63SDavid Woodhouse de = (struct buffered_dirent *)((char *)de + reclen);
213814f7dd63SDavid Woodhouse }
21392f9092e1SDavid Woodhouse if (size > 0) /* We bailed out early */
21402f9092e1SDavid Woodhouse break;
21412f9092e1SDavid Woodhouse
2142c002a6c7SDavid Woodhouse offset = vfs_llseek(file, 0, SEEK_CUR);
214314f7dd63SDavid Woodhouse }
214414f7dd63SDavid Woodhouse
214514f7dd63SDavid Woodhouse free_page((unsigned long)(buf.dirent));
21462628b766SDavid Woodhouse
21472628b766SDavid Woodhouse if (host_err)
21482628b766SDavid Woodhouse return nfserrno(host_err);
214914f7dd63SDavid Woodhouse
215014f7dd63SDavid Woodhouse *offsetp = offset;
21512628b766SDavid Woodhouse return cdp->err;
21522628b766SDavid Woodhouse }
21532628b766SDavid Woodhouse
2154a853ed55SChuck Lever /**
2155a853ed55SChuck Lever * nfsd_readdir - Read entries from a directory
2156a853ed55SChuck Lever * @rqstp: RPC transaction context
2157a853ed55SChuck Lever * @fhp: NFS file handle of directory to be read
2158a853ed55SChuck Lever * @offsetp: OUT: seek offset of final entry that was read
2159a853ed55SChuck Lever * @cdp: OUT: an eof error value
2160a853ed55SChuck Lever * @func: entry filler actor
2161a853ed55SChuck Lever *
2162a853ed55SChuck Lever * This implementation ignores the NFSv3/4 verifier cookie.
2163a853ed55SChuck Lever *
2164a853ed55SChuck Lever * NB: normal system calls hold file->f_pos_lock when calling
2165a853ed55SChuck Lever * ->iterate_shared and ->llseek, but nfsd_readdir() does not.
2166a853ed55SChuck Lever * Because the struct file acquired here is not visible to other
2167a853ed55SChuck Lever * threads, it's internal state does not need mutex protection.
2168a853ed55SChuck Lever *
2169a853ed55SChuck Lever * Returns nfs_ok on success, otherwise an nfsstat code is
2170a853ed55SChuck Lever * returned.
21711da177e4SLinus Torvalds */
21726264d69dSAl Viro __be32
nfsd_readdir(struct svc_rqst * rqstp,struct svc_fh * fhp,loff_t * offsetp,struct readdir_cd * cdp,nfsd_filldir_t func)21731da177e4SLinus Torvalds nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
2174ac7576f4SMiklos Szeredi struct readdir_cd *cdp, nfsd_filldir_t func)
21751da177e4SLinus Torvalds {
21766264d69dSAl Viro __be32 err;
21771da177e4SLinus Torvalds struct file *file;
21781da177e4SLinus Torvalds loff_t offset = *offsetp;
217906effdbbSBernd Schubert int may_flags = NFSD_MAY_READ;
21801da177e4SLinus Torvalds
218106effdbbSBernd Schubert /* NFSv2 only supports 32 bit cookies */
218206effdbbSBernd Schubert if (rqstp->rq_vers > 2)
218306effdbbSBernd Schubert may_flags |= NFSD_MAY_64BIT_COOKIE;
218406effdbbSBernd Schubert
218506effdbbSBernd Schubert err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file);
21861da177e4SLinus Torvalds if (err)
21871da177e4SLinus Torvalds goto out;
21881da177e4SLinus Torvalds
2189b108fe6bSJeff Layton offset = vfs_llseek(file, offset, SEEK_SET);
21901da177e4SLinus Torvalds if (offset < 0) {
21911da177e4SLinus Torvalds err = nfserrno((int)offset);
21921da177e4SLinus Torvalds goto out_close;
21931da177e4SLinus Torvalds }
21941da177e4SLinus Torvalds
21956019ce07SChuck Lever err = nfsd_buffered_readdir(file, fhp, func, cdp, offsetp);
21961da177e4SLinus Torvalds
21971da177e4SLinus Torvalds if (err == nfserr_eof || err == nfserr_toosmall)
21981da177e4SLinus Torvalds err = nfs_ok; /* can still be found in ->err */
21991da177e4SLinus Torvalds out_close:
22005ff318f6SNeilBrown nfsd_filp_close(file);
22011da177e4SLinus Torvalds out:
22021da177e4SLinus Torvalds return err;
22031da177e4SLinus Torvalds }
22041da177e4SLinus Torvalds
22055ff318f6SNeilBrown /**
22065ff318f6SNeilBrown * nfsd_filp_close: close a file synchronously
22075ff318f6SNeilBrown * @fp: the file to close
22085ff318f6SNeilBrown *
22095ff318f6SNeilBrown * nfsd_filp_close() is similar in behaviour to filp_close().
22105ff318f6SNeilBrown * The difference is that if this is the final close on the
22115ff318f6SNeilBrown * file, the that finalisation happens immediately, rather then
22125ff318f6SNeilBrown * being handed over to a work_queue, as it the case for
22135ff318f6SNeilBrown * filp_close().
22145ff318f6SNeilBrown * When a user-space process closes a file (even when using
22155ff318f6SNeilBrown * filp_close() the finalisation happens before returning to
22165ff318f6SNeilBrown * userspace, so it is effectively synchronous. When a kernel thread
22175ff318f6SNeilBrown * uses file_close(), on the other hand, the handling is completely
22185ff318f6SNeilBrown * asynchronous. This means that any cost imposed by that finalisation
22195ff318f6SNeilBrown * is not imposed on the nfsd thread, and nfsd could potentually
22205ff318f6SNeilBrown * close files more quickly than the work queue finalises the close,
22215ff318f6SNeilBrown * which would lead to unbounded growth in the queue.
22225ff318f6SNeilBrown *
22235ff318f6SNeilBrown * In some contexts is it not safe to synchronously wait for
22245ff318f6SNeilBrown * close finalisation (see comment for __fput_sync()), but nfsd
22255ff318f6SNeilBrown * does not match those contexts. In partcilarly it does not, at the
22265ff318f6SNeilBrown * time that this function is called, hold and locks and no finalisation
22275ff318f6SNeilBrown * of any file, socket, or device driver would have any cause to wait
22285ff318f6SNeilBrown * for nfsd to make progress.
22295ff318f6SNeilBrown */
nfsd_filp_close(struct file * fp)22305ff318f6SNeilBrown void nfsd_filp_close(struct file *fp)
22315ff318f6SNeilBrown {
22325ff318f6SNeilBrown get_file(fp);
22335ff318f6SNeilBrown filp_close(fp, NULL);
22345ff318f6SNeilBrown __fput_sync(fp);
22355ff318f6SNeilBrown }
22365ff318f6SNeilBrown
22371da177e4SLinus Torvalds /*
22381da177e4SLinus Torvalds * Get file system stats
22391da177e4SLinus Torvalds * N.B. After this call fhp needs an fh_put
22401da177e4SLinus Torvalds */
22416264d69dSAl Viro __be32
nfsd_statfs(struct svc_rqst * rqstp,struct svc_fh * fhp,struct kstatfs * stat,int access)224204716e66SJ. Bruce Fields nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
22431da177e4SLinus Torvalds {
2244f6360efbSTakashi Iwai __be32 err;
2245f6360efbSTakashi Iwai
2246f6360efbSTakashi Iwai err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
2247f6360efbSTakashi Iwai if (!err) {
2248ebabe9a9SChristoph Hellwig struct path path = {
2249ebabe9a9SChristoph Hellwig .mnt = fhp->fh_export->ex_path.mnt,
2250ebabe9a9SChristoph Hellwig .dentry = fhp->fh_dentry,
2251ebabe9a9SChristoph Hellwig };
2252f6360efbSTakashi Iwai if (vfs_statfs(&path, stat))
22531da177e4SLinus Torvalds err = nfserr_io;
2254f6360efbSTakashi Iwai }
22551da177e4SLinus Torvalds return err;
22561da177e4SLinus Torvalds }
22571da177e4SLinus Torvalds
exp_rdonly(struct svc_rqst * rqstp,struct svc_export * exp)2258c7d51402SJ. Bruce Fields static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp)
2259e22841c6SJ. Bruce Fields {
2260c7d51402SJ. Bruce Fields return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY;
2261e22841c6SJ. Bruce Fields }
2262e22841c6SJ. Bruce Fields
226332119446SFrank van der Linden #ifdef CONFIG_NFSD_V4
226432119446SFrank van der Linden /*
226532119446SFrank van der Linden * Helper function to translate error numbers. In the case of xattr operations,
226632119446SFrank van der Linden * some error codes need to be translated outside of the standard translations.
226732119446SFrank van der Linden *
226832119446SFrank van der Linden * ENODATA needs to be translated to nfserr_noxattr.
226932119446SFrank van der Linden * E2BIG to nfserr_xattr2big.
227032119446SFrank van der Linden *
227132119446SFrank van der Linden * Additionally, vfs_listxattr can return -ERANGE. This means that the
227232119446SFrank van der Linden * file has too many extended attributes to retrieve inside an
227332119446SFrank van der Linden * XATTR_LIST_MAX sized buffer. This is a bug in the xattr implementation:
227432119446SFrank van der Linden * filesystems will allow the adding of extended attributes until they hit
227532119446SFrank van der Linden * their own internal limit. This limit may be larger than XATTR_LIST_MAX.
227632119446SFrank van der Linden * So, at that point, the attributes are present and valid, but can't
227732119446SFrank van der Linden * be retrieved using listxattr, since the upper level xattr code enforces
227832119446SFrank van der Linden * the XATTR_LIST_MAX limit.
227932119446SFrank van der Linden *
228032119446SFrank van der Linden * This bug means that we need to deal with listxattr returning -ERANGE. The
228132119446SFrank van der Linden * best mapping is to return TOOSMALL.
228232119446SFrank van der Linden */
228332119446SFrank van der Linden static __be32
nfsd_xattr_errno(int err)228432119446SFrank van der Linden nfsd_xattr_errno(int err)
228532119446SFrank van der Linden {
228632119446SFrank van der Linden switch (err) {
228732119446SFrank van der Linden case -ENODATA:
228832119446SFrank van der Linden return nfserr_noxattr;
228932119446SFrank van der Linden case -E2BIG:
229032119446SFrank van der Linden return nfserr_xattr2big;
229132119446SFrank van der Linden case -ERANGE:
229232119446SFrank van der Linden return nfserr_toosmall;
229332119446SFrank van der Linden }
229432119446SFrank van der Linden return nfserrno(err);
229532119446SFrank van der Linden }
229632119446SFrank van der Linden
229732119446SFrank van der Linden /*
229832119446SFrank van der Linden * Retrieve the specified user extended attribute. To avoid always
229932119446SFrank van der Linden * having to allocate the maximum size (since we are not getting
230032119446SFrank van der Linden * a maximum size from the RPC), do a probe + alloc. Hold a reader
230132119446SFrank van der Linden * lock on i_rwsem to prevent the extended attribute from changing
230232119446SFrank van der Linden * size while we're doing this.
230332119446SFrank van der Linden */
230432119446SFrank van der Linden __be32
nfsd_getxattr(struct svc_rqst * rqstp,struct svc_fh * fhp,char * name,void ** bufp,int * lenp)230532119446SFrank van der Linden nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
230632119446SFrank van der Linden void **bufp, int *lenp)
230732119446SFrank van der Linden {
230832119446SFrank van der Linden ssize_t len;
230932119446SFrank van der Linden __be32 err;
231032119446SFrank van der Linden char *buf;
231132119446SFrank van der Linden struct inode *inode;
231232119446SFrank van der Linden struct dentry *dentry;
231332119446SFrank van der Linden
231432119446SFrank van der Linden err = fh_verify(rqstp, fhp, 0, NFSD_MAY_READ);
231532119446SFrank van der Linden if (err)
231632119446SFrank van der Linden return err;
231732119446SFrank van der Linden
231832119446SFrank van der Linden err = nfs_ok;
231932119446SFrank van der Linden dentry = fhp->fh_dentry;
232032119446SFrank van der Linden inode = d_inode(dentry);
232132119446SFrank van der Linden
232232119446SFrank van der Linden inode_lock_shared(inode);
232332119446SFrank van der Linden
23244609e1f1SChristian Brauner len = vfs_getxattr(&nop_mnt_idmap, dentry, name, NULL, 0);
232532119446SFrank van der Linden
232632119446SFrank van der Linden /*
232732119446SFrank van der Linden * Zero-length attribute, just return.
232832119446SFrank van der Linden */
232932119446SFrank van der Linden if (len == 0) {
233032119446SFrank van der Linden *bufp = NULL;
233132119446SFrank van der Linden *lenp = 0;
233232119446SFrank van der Linden goto out;
233332119446SFrank van der Linden }
233432119446SFrank van der Linden
233532119446SFrank van der Linden if (len < 0) {
233632119446SFrank van der Linden err = nfsd_xattr_errno(len);
233732119446SFrank van der Linden goto out;
233832119446SFrank van der Linden }
233932119446SFrank van der Linden
234032119446SFrank van der Linden if (len > *lenp) {
234132119446SFrank van der Linden err = nfserr_toosmall;
234232119446SFrank van der Linden goto out;
234332119446SFrank van der Linden }
234432119446SFrank van der Linden
234522b620ecSChuck Lever buf = kvmalloc(len, GFP_KERNEL);
234632119446SFrank van der Linden if (buf == NULL) {
234732119446SFrank van der Linden err = nfserr_jukebox;
234832119446SFrank van der Linden goto out;
234932119446SFrank van der Linden }
235032119446SFrank van der Linden
23514609e1f1SChristian Brauner len = vfs_getxattr(&nop_mnt_idmap, dentry, name, buf, len);
235232119446SFrank van der Linden if (len <= 0) {
235332119446SFrank van der Linden kvfree(buf);
235432119446SFrank van der Linden buf = NULL;
235532119446SFrank van der Linden err = nfsd_xattr_errno(len);
235632119446SFrank van der Linden }
235732119446SFrank van der Linden
235832119446SFrank van der Linden *lenp = len;
235932119446SFrank van der Linden *bufp = buf;
236032119446SFrank van der Linden
236132119446SFrank van der Linden out:
236232119446SFrank van der Linden inode_unlock_shared(inode);
236332119446SFrank van der Linden
236432119446SFrank van der Linden return err;
236532119446SFrank van der Linden }
236632119446SFrank van der Linden
236732119446SFrank van der Linden /*
236832119446SFrank van der Linden * Retrieve the xattr names. Since we can't know how many are
236932119446SFrank van der Linden * user extended attributes, we must get all attributes here,
237032119446SFrank van der Linden * and have the XDR encode filter out the "user." ones.
237132119446SFrank van der Linden *
237232119446SFrank van der Linden * While this could always just allocate an XATTR_LIST_MAX
237332119446SFrank van der Linden * buffer, that's a waste, so do a probe + allocate. To
237432119446SFrank van der Linden * avoid any changes between the probe and allocate, wrap
237532119446SFrank van der Linden * this in inode_lock.
237632119446SFrank van der Linden */
237732119446SFrank van der Linden __be32
nfsd_listxattr(struct svc_rqst * rqstp,struct svc_fh * fhp,char ** bufp,int * lenp)237832119446SFrank van der Linden nfsd_listxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char **bufp,
237932119446SFrank van der Linden int *lenp)
238032119446SFrank van der Linden {
238132119446SFrank van der Linden ssize_t len;
238232119446SFrank van der Linden __be32 err;
238332119446SFrank van der Linden char *buf;
238432119446SFrank van der Linden struct inode *inode;
238532119446SFrank van der Linden struct dentry *dentry;
238632119446SFrank van der Linden
238732119446SFrank van der Linden err = fh_verify(rqstp, fhp, 0, NFSD_MAY_READ);
238832119446SFrank van der Linden if (err)
238932119446SFrank van der Linden return err;
239032119446SFrank van der Linden
239132119446SFrank van der Linden dentry = fhp->fh_dentry;
239232119446SFrank van der Linden inode = d_inode(dentry);
239332119446SFrank van der Linden *lenp = 0;
239432119446SFrank van der Linden
239532119446SFrank van der Linden inode_lock_shared(inode);
239632119446SFrank van der Linden
239732119446SFrank van der Linden len = vfs_listxattr(dentry, NULL, 0);
239832119446SFrank van der Linden if (len <= 0) {
239932119446SFrank van der Linden err = nfsd_xattr_errno(len);
240032119446SFrank van der Linden goto out;
240132119446SFrank van der Linden }
240232119446SFrank van der Linden
240332119446SFrank van der Linden if (len > XATTR_LIST_MAX) {
240432119446SFrank van der Linden err = nfserr_xattr2big;
240532119446SFrank van der Linden goto out;
240632119446SFrank van der Linden }
240732119446SFrank van der Linden
240822b620ecSChuck Lever buf = kvmalloc(len, GFP_KERNEL);
240932119446SFrank van der Linden if (buf == NULL) {
241032119446SFrank van der Linden err = nfserr_jukebox;
241132119446SFrank van der Linden goto out;
241232119446SFrank van der Linden }
241332119446SFrank van der Linden
241432119446SFrank van der Linden len = vfs_listxattr(dentry, buf, len);
241532119446SFrank van der Linden if (len <= 0) {
241632119446SFrank van der Linden kvfree(buf);
241732119446SFrank van der Linden err = nfsd_xattr_errno(len);
241832119446SFrank van der Linden goto out;
241932119446SFrank van der Linden }
242032119446SFrank van der Linden
242132119446SFrank van der Linden *lenp = len;
242232119446SFrank van der Linden *bufp = buf;
242332119446SFrank van der Linden
242432119446SFrank van der Linden err = nfs_ok;
242532119446SFrank van der Linden out:
242632119446SFrank van der Linden inode_unlock_shared(inode);
242732119446SFrank van der Linden
242832119446SFrank van der Linden return err;
242932119446SFrank van der Linden }
243032119446SFrank van der Linden
2431bb4d53d6SNeilBrown /**
2432bb4d53d6SNeilBrown * nfsd_removexattr - Remove an extended attribute
2433bb4d53d6SNeilBrown * @rqstp: RPC transaction being executed
2434bb4d53d6SNeilBrown * @fhp: NFS filehandle of object with xattr to remove
2435bb4d53d6SNeilBrown * @name: name of xattr to remove (NUL-terminate)
2436bb4d53d6SNeilBrown *
2437bb4d53d6SNeilBrown * Pass in a NULL pointer for delegated_inode, and let the client deal
2438bb4d53d6SNeilBrown * with NFS4ERR_DELAY (same as with e.g. setattr and remove).
2439bb4d53d6SNeilBrown *
2440bb4d53d6SNeilBrown * Returns nfs_ok on success, or an nfsstat in network byte order.
244132119446SFrank van der Linden */
244232119446SFrank van der Linden __be32
nfsd_removexattr(struct svc_rqst * rqstp,struct svc_fh * fhp,char * name)244332119446SFrank van der Linden nfsd_removexattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name)
244432119446SFrank van der Linden {
24458237284aSChuck Lever __be32 err;
24468237284aSChuck Lever int ret;
244732119446SFrank van der Linden
244832119446SFrank van der Linden err = fh_verify(rqstp, fhp, 0, NFSD_MAY_WRITE);
244932119446SFrank van der Linden if (err)
245032119446SFrank van der Linden return err;
245132119446SFrank van der Linden
245232119446SFrank van der Linden ret = fh_want_write(fhp);
245332119446SFrank van der Linden if (ret)
245432119446SFrank van der Linden return nfserrno(ret);
245532119446SFrank van der Linden
2456bb4d53d6SNeilBrown inode_lock(fhp->fh_dentry->d_inode);
2457a332018aSJeff Layton err = fh_fill_pre_attrs(fhp);
2458a332018aSJeff Layton if (err != nfs_ok)
2459a332018aSJeff Layton goto out_unlock;
24604609e1f1SChristian Brauner ret = __vfs_removexattr_locked(&nop_mnt_idmap, fhp->fh_dentry,
2461c7c7a1a1STycho Andersen name, NULL);
2462a332018aSJeff Layton err = nfsd_xattr_errno(ret);
2463bb4d53d6SNeilBrown fh_fill_post_attrs(fhp);
2464a332018aSJeff Layton out_unlock:
2465bb4d53d6SNeilBrown inode_unlock(fhp->fh_dentry->d_inode);
246632119446SFrank van der Linden fh_drop_write(fhp);
246732119446SFrank van der Linden
2468a332018aSJeff Layton return err;
246932119446SFrank van der Linden }
247032119446SFrank van der Linden
247132119446SFrank van der Linden __be32
nfsd_setxattr(struct svc_rqst * rqstp,struct svc_fh * fhp,char * name,void * buf,u32 len,u32 flags)247232119446SFrank van der Linden nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
247332119446SFrank van der Linden void *buf, u32 len, u32 flags)
247432119446SFrank van der Linden {
24758237284aSChuck Lever __be32 err;
24768237284aSChuck Lever int ret;
247732119446SFrank van der Linden
247832119446SFrank van der Linden err = fh_verify(rqstp, fhp, 0, NFSD_MAY_WRITE);
247932119446SFrank van der Linden if (err)
248032119446SFrank van der Linden return err;
248132119446SFrank van der Linden
248232119446SFrank van der Linden ret = fh_want_write(fhp);
248332119446SFrank van der Linden if (ret)
248432119446SFrank van der Linden return nfserrno(ret);
2485bb4d53d6SNeilBrown inode_lock(fhp->fh_dentry->d_inode);
2486a332018aSJeff Layton err = fh_fill_pre_attrs(fhp);
2487a332018aSJeff Layton if (err != nfs_ok)
2488a332018aSJeff Layton goto out_unlock;
2489a332018aSJeff Layton ret = __vfs_setxattr_locked(&nop_mnt_idmap, fhp->fh_dentry,
2490a332018aSJeff Layton name, buf, len, flags, NULL);
2491bb4d53d6SNeilBrown fh_fill_post_attrs(fhp);
2492a332018aSJeff Layton err = nfsd_xattr_errno(ret);
2493a332018aSJeff Layton out_unlock:
2494bb4d53d6SNeilBrown inode_unlock(fhp->fh_dentry->d_inode);
249532119446SFrank van der Linden fh_drop_write(fhp);
2496a332018aSJeff Layton return err;
249732119446SFrank van der Linden }
249832119446SFrank van der Linden #endif
249932119446SFrank van der Linden
25001da177e4SLinus Torvalds /*
25011da177e4SLinus Torvalds * Check for a user's access permissions to this inode.
25021da177e4SLinus Torvalds */
25036264d69dSAl Viro __be32
nfsd_permission(struct svc_rqst * rqstp,struct svc_export * exp,struct dentry * dentry,int acc)25040ec757dfSJ. Bruce Fields nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
25050ec757dfSJ. Bruce Fields struct dentry *dentry, int acc)
25061da177e4SLinus Torvalds {
25072b0143b5SDavid Howells struct inode *inode = d_inode(dentry);
25081da177e4SLinus Torvalds int err;
25091da177e4SLinus Torvalds
2510aea93397SJ. Bruce Fields if ((acc & NFSD_MAY_MASK) == NFSD_MAY_NOP)
25111da177e4SLinus Torvalds return 0;
25121da177e4SLinus Torvalds #if 0
25131da177e4SLinus Torvalds dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n",
25141da177e4SLinus Torvalds acc,
25158837abcaSMiklos Szeredi (acc & NFSD_MAY_READ)? " read" : "",
25168837abcaSMiklos Szeredi (acc & NFSD_MAY_WRITE)? " write" : "",
25178837abcaSMiklos Szeredi (acc & NFSD_MAY_EXEC)? " exec" : "",
25188837abcaSMiklos Szeredi (acc & NFSD_MAY_SATTR)? " sattr" : "",
25198837abcaSMiklos Szeredi (acc & NFSD_MAY_TRUNC)? " trunc" : "",
25208837abcaSMiklos Szeredi (acc & NFSD_MAY_LOCK)? " lock" : "",
25218837abcaSMiklos Szeredi (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "",
25221da177e4SLinus Torvalds inode->i_mode,
25231da177e4SLinus Torvalds IS_IMMUTABLE(inode)? " immut" : "",
25241da177e4SLinus Torvalds IS_APPEND(inode)? " append" : "",
25252c463e95SDave Hansen __mnt_is_readonly(exp->ex_path.mnt)? " ro" : "");
25261da177e4SLinus Torvalds dprintk(" owner %d/%d user %d/%d\n",
25275cc0a840SDavid Howells inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid());
25281da177e4SLinus Torvalds #endif
25291da177e4SLinus Torvalds
25301da177e4SLinus Torvalds /* Normally we reject any write/sattr etc access on a read-only file
25311da177e4SLinus Torvalds * system. But if it is IRIX doing check on write-access for a
25321da177e4SLinus Torvalds * device special file, we ignore rofs.
25331da177e4SLinus Torvalds */
25348837abcaSMiklos Szeredi if (!(acc & NFSD_MAY_LOCAL_ACCESS))
25358837abcaSMiklos Szeredi if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) {
25362c463e95SDave Hansen if (exp_rdonly(rqstp, exp) ||
25372c463e95SDave Hansen __mnt_is_readonly(exp->ex_path.mnt))
25381da177e4SLinus Torvalds return nfserr_rofs;
25398837abcaSMiklos Szeredi if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode))
25401da177e4SLinus Torvalds return nfserr_perm;
25411da177e4SLinus Torvalds }
25428837abcaSMiklos Szeredi if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode))
25431da177e4SLinus Torvalds return nfserr_perm;
25441da177e4SLinus Torvalds
25458837abcaSMiklos Szeredi if (acc & NFSD_MAY_LOCK) {
25461da177e4SLinus Torvalds /* If we cannot rely on authentication in NLM requests,
25471da177e4SLinus Torvalds * just allow locks, otherwise require read permission, or
25481da177e4SLinus Torvalds * ownership
25491da177e4SLinus Torvalds */
25501da177e4SLinus Torvalds if (exp->ex_flags & NFSEXP_NOAUTHNLM)
25511da177e4SLinus Torvalds return 0;
25521da177e4SLinus Torvalds else
25538837abcaSMiklos Szeredi acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE;
25541da177e4SLinus Torvalds }
25551da177e4SLinus Torvalds /*
25561da177e4SLinus Torvalds * The file owner always gets access permission for accesses that
25571da177e4SLinus Torvalds * would normally be checked at open time. This is to make
25581da177e4SLinus Torvalds * file access work even when the client has done a fchmod(fd, 0).
25591da177e4SLinus Torvalds *
25601da177e4SLinus Torvalds * However, `cp foo bar' should fail nevertheless when bar is
25611da177e4SLinus Torvalds * readonly. A sensible way to do this might be to reject all
25621da177e4SLinus Torvalds * attempts to truncate a read-only file, because a creat() call
25631da177e4SLinus Torvalds * always implies file truncation.
25641da177e4SLinus Torvalds * ... but this isn't really fair. A process may reasonably call
25651da177e4SLinus Torvalds * ftruncate on an open file descriptor on a file with perm 000.
25661da177e4SLinus Torvalds * We must trust the client to do permission checking - using "ACCESS"
25671da177e4SLinus Torvalds * with NFSv3.
25681da177e4SLinus Torvalds */
25698837abcaSMiklos Szeredi if ((acc & NFSD_MAY_OWNER_OVERRIDE) &&
25706fab8779SEric W. Biederman uid_eq(inode->i_uid, current_fsuid()))
25711da177e4SLinus Torvalds return 0;
25721da177e4SLinus Torvalds
25738837abcaSMiklos Szeredi /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
25744609e1f1SChristian Brauner err = inode_permission(&nop_mnt_idmap, inode,
257547291baaSChristian Brauner acc & (MAY_READ | MAY_WRITE | MAY_EXEC));
25761da177e4SLinus Torvalds
25771da177e4SLinus Torvalds /* Allow read access to binaries even when mode 111 */
25781da177e4SLinus Torvalds if (err == -EACCES && S_ISREG(inode->i_mode) &&
2579a043226bSJ. Bruce Fields (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
2580a043226bSJ. Bruce Fields acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
25814609e1f1SChristian Brauner err = inode_permission(&nop_mnt_idmap, inode, MAY_EXEC);
25821da177e4SLinus Torvalds
25831da177e4SLinus Torvalds return err? nfserrno(err) : 0;
25841da177e4SLinus Torvalds }
2585