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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
1da177e4 LT |
3 | * File operations used by nfsd. Some of these have been ripped from |
4 | * other parts of the kernel because they weren't exported, others | |
5 | * are partial duplicates with added or changed functionality. | |
6 | * | |
7 | * Note that several functions dget() the dentry upon which they want | |
8 | * to act, most notably those that create directory entries. Response | |
9 | * dentry's are dput()'d if necessary in the release callback. | |
10 | * So if you notice code paths that apparently fail to dput() the | |
11 | * dentry, don't worry--they have been taken care of. | |
12 | * | |
13 | * Copyright (C) 1995-1999 Olaf Kirch <okir@monad.swb.de> | |
14 | * Zerocpy NFS support (C) 2002 Hirokazu Takahashi <taka@valinux.co.jp> | |
15 | */ | |
16 | ||
1da177e4 LT |
17 | #include <linux/fs.h> |
18 | #include <linux/file.h> | |
d6b29d7c | 19 | #include <linux/splice.h> |
95d871f0 | 20 | #include <linux/falloc.h> |
1da177e4 | 21 | #include <linux/fcntl.h> |
1da177e4 | 22 | #include <linux/namei.h> |
1da177e4 | 23 | #include <linux/delay.h> |
0eeca283 | 24 | #include <linux/fsnotify.h> |
1da177e4 | 25 | #include <linux/posix_acl_xattr.h> |
1da177e4 | 26 | #include <linux/xattr.h> |
9a74af21 BH |
27 | #include <linux/jhash.h> |
28 | #include <linux/ima.h> | |
5a0e3ad6 | 29 | #include <linux/slab.h> |
7c0f6ba6 | 30 | #include <linux/uaccess.h> |
f501912a BM |
31 | #include <linux/exportfs.h> |
32 | #include <linux/writeback.h> | |
18032ca0 | 33 | #include <linux/security.h> |
9a74af21 BH |
34 | |
35 | #ifdef CONFIG_NFSD_V3 | |
36 | #include "xdr3.h" | |
37 | #endif /* CONFIG_NFSD_V3 */ | |
38 | ||
5be196e5 | 39 | #ifdef CONFIG_NFSD_V4 |
ffa0160a | 40 | #include "../internal.h" |
2ca72e17 BF |
41 | #include "acl.h" |
42 | #include "idmap.h" | |
1da177e4 LT |
43 | #endif /* CONFIG_NFSD_V4 */ |
44 | ||
9a74af21 BH |
45 | #include "nfsd.h" |
46 | #include "vfs.h" | |
6e8b50d1 | 47 | #include "trace.h" |
1da177e4 LT |
48 | |
49 | #define NFSDDBG_FACILITY NFSDDBG_FILEOP | |
1da177e4 LT |
50 | |
51 | ||
1da177e4 LT |
52 | /* |
53 | * This is a cache of readahead params that help us choose the proper | |
54 | * readahead strategy. Initially, we set all readahead parameters to 0 | |
55 | * and let the VFS handle things. | |
56 | * If you increase the number of cached files very much, you'll need to | |
57 | * add a hash table here. | |
58 | */ | |
59 | struct raparms { | |
60 | struct raparms *p_next; | |
61 | unsigned int p_count; | |
62 | ino_t p_ino; | |
63 | dev_t p_dev; | |
64 | int p_set; | |
65 | struct file_ra_state p_ra; | |
fce1456a | 66 | unsigned int p_hindex; |
1da177e4 LT |
67 | }; |
68 | ||
fce1456a GB |
69 | struct raparm_hbucket { |
70 | struct raparms *pb_head; | |
71 | spinlock_t pb_lock; | |
72 | } ____cacheline_aligned_in_smp; | |
73 | ||
fce1456a GB |
74 | #define RAPARM_HASH_BITS 4 |
75 | #define RAPARM_HASH_SIZE (1<<RAPARM_HASH_BITS) | |
76 | #define RAPARM_HASH_MASK (RAPARM_HASH_SIZE-1) | |
77 | static struct raparm_hbucket raparm_hash[RAPARM_HASH_SIZE]; | |
1da177e4 LT |
78 | |
79 | /* | |
80 | * Called from nfsd_lookup and encode_dirent. Check if we have crossed | |
81 | * a mount point. | |
e0bb89ef | 82 | * Returns -EAGAIN or -ETIMEDOUT leaving *dpp and *expp unchanged, |
1da177e4 LT |
83 | * or nfs_ok having possibly changed *dpp and *expp |
84 | */ | |
85 | int | |
86 | nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, | |
87 | struct svc_export **expp) | |
88 | { | |
89 | struct svc_export *exp = *expp, *exp2 = NULL; | |
90 | struct dentry *dentry = *dpp; | |
91c9fa8f AV |
91 | struct path path = {.mnt = mntget(exp->ex_path.mnt), |
92 | .dentry = dget(dentry)}; | |
6264d69d | 93 | int err = 0; |
1da177e4 | 94 | |
7cc90cc3 | 95 | err = follow_down(&path); |
cc53ce53 DH |
96 | if (err < 0) |
97 | goto out; | |
99bbf6ec N |
98 | if (path.mnt == exp->ex_path.mnt && path.dentry == dentry && |
99 | nfsd_mountpoint(dentry, exp) == 2) { | |
100 | /* This is only a mountpoint in some other namespace */ | |
101 | path_put(&path); | |
102 | goto out; | |
103 | } | |
1da177e4 | 104 | |
91c9fa8f | 105 | exp2 = rqst_exp_get_by_name(rqstp, &path); |
1da177e4 | 106 | if (IS_ERR(exp2)) { |
3b6cee7b BF |
107 | err = PTR_ERR(exp2); |
108 | /* | |
109 | * We normally allow NFS clients to continue | |
110 | * "underneath" a mountpoint that is not exported. | |
111 | * The exception is V4ROOT, where no traversal is ever | |
112 | * allowed without an explicit export of the new | |
113 | * directory. | |
114 | */ | |
115 | if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT)) | |
116 | err = 0; | |
91c9fa8f | 117 | path_put(&path); |
1da177e4 LT |
118 | goto out; |
119 | } | |
3c394dda SD |
120 | if (nfsd_v4client(rqstp) || |
121 | (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) { | |
1da177e4 | 122 | /* successfully crossed mount point */ |
1644ccc8 | 123 | /* |
91c9fa8f AV |
124 | * This is subtle: path.dentry is *not* on path.mnt |
125 | * at this point. The only reason we are safe is that | |
126 | * original mnt is pinned down by exp, so we should | |
127 | * put path *before* putting exp | |
1644ccc8 | 128 | */ |
91c9fa8f AV |
129 | *dpp = path.dentry; |
130 | path.dentry = dentry; | |
1644ccc8 | 131 | *expp = exp2; |
91c9fa8f | 132 | exp2 = exp; |
1da177e4 | 133 | } |
91c9fa8f AV |
134 | path_put(&path); |
135 | exp_put(exp2); | |
1da177e4 LT |
136 | out: |
137 | return err; | |
138 | } | |
139 | ||
289ede45 BF |
140 | static void follow_to_parent(struct path *path) |
141 | { | |
142 | struct dentry *dp; | |
143 | ||
144 | while (path->dentry == path->mnt->mnt_root && follow_up(path)) | |
145 | ; | |
146 | dp = dget_parent(path->dentry); | |
147 | dput(path->dentry); | |
148 | path->dentry = dp; | |
149 | } | |
150 | ||
151 | static int nfsd_lookup_parent(struct svc_rqst *rqstp, struct dentry *dparent, struct svc_export **exp, struct dentry **dentryp) | |
152 | { | |
153 | struct svc_export *exp2; | |
154 | struct path path = {.mnt = mntget((*exp)->ex_path.mnt), | |
155 | .dentry = dget(dparent)}; | |
156 | ||
157 | follow_to_parent(&path); | |
158 | ||
159 | exp2 = rqst_exp_parent(rqstp, &path); | |
160 | if (PTR_ERR(exp2) == -ENOENT) { | |
161 | *dentryp = dget(dparent); | |
162 | } else if (IS_ERR(exp2)) { | |
163 | path_put(&path); | |
164 | return PTR_ERR(exp2); | |
165 | } else { | |
166 | *dentryp = dget(path.dentry); | |
167 | exp_put(*exp); | |
168 | *exp = exp2; | |
169 | } | |
170 | path_put(&path); | |
171 | return 0; | |
172 | } | |
173 | ||
82ead7fe BF |
174 | /* |
175 | * For nfsd purposes, we treat V4ROOT exports as though there was an | |
176 | * export at *every* directory. | |
99bbf6ec N |
177 | * We return: |
178 | * '1' if this dentry *must* be an export point, | |
179 | * '2' if it might be, if there is really a mount here, and | |
180 | * '0' if there is no chance of an export point here. | |
82ead7fe | 181 | */ |
3227fa41 | 182 | int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp) |
82ead7fe | 183 | { |
99bbf6ec N |
184 | if (!d_inode(dentry)) |
185 | return 0; | |
186 | if (exp->ex_flags & NFSEXP_V4ROOT) | |
82ead7fe | 187 | return 1; |
11fcee02 TM |
188 | if (nfsd4_is_junction(dentry)) |
189 | return 1; | |
99bbf6ec N |
190 | if (d_mountpoint(dentry)) |
191 | /* | |
192 | * Might only be a mountpoint in a different namespace, | |
193 | * but we need to check. | |
194 | */ | |
195 | return 2; | |
196 | return 0; | |
82ead7fe BF |
197 | } |
198 | ||
6264d69d | 199 | __be32 |
6c0a654d | 200 | nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp, |
5a022fc8 | 201 | const char *name, unsigned int len, |
6c0a654d | 202 | struct svc_export **exp_ret, struct dentry **dentry_ret) |
1da177e4 LT |
203 | { |
204 | struct svc_export *exp; | |
205 | struct dentry *dparent; | |
206 | struct dentry *dentry; | |
6264d69d | 207 | int host_err; |
1da177e4 LT |
208 | |
209 | dprintk("nfsd: nfsd_lookup(fh %s, %.*s)\n", SVCFH_fmt(fhp), len,name); | |
210 | ||
1da177e4 | 211 | dparent = fhp->fh_dentry; |
bf18f163 | 212 | exp = exp_get(fhp->fh_export); |
1da177e4 | 213 | |
1da177e4 LT |
214 | /* Lookup the name, but don't follow links */ |
215 | if (isdotent(name, len)) { | |
216 | if (len==1) | |
217 | dentry = dget(dparent); | |
54775491 | 218 | else if (dparent != exp->ex_path.dentry) |
1da177e4 | 219 | dentry = dget_parent(dparent); |
fed83811 | 220 | else if (!EX_NOHIDE(exp) && !nfsd_v4client(rqstp)) |
1da177e4 LT |
221 | dentry = dget(dparent); /* .. == . just like at / */ |
222 | else { | |
223 | /* checking mountpoint crossing is very different when stepping up */ | |
289ede45 BF |
224 | host_err = nfsd_lookup_parent(rqstp, dparent, &exp, &dentry); |
225 | if (host_err) | |
1da177e4 | 226 | goto out_nfserr; |
1da177e4 LT |
227 | } |
228 | } else { | |
4335723e BF |
229 | /* |
230 | * In the nfsd4_open() case, this may be held across | |
231 | * subsequent open and delegation acquisition which may | |
232 | * need to take the child's i_mutex: | |
233 | */ | |
234 | fh_lock_nested(fhp, I_MUTEX_PARENT); | |
1da177e4 | 235 | dentry = lookup_one_len(name, dparent, len); |
6264d69d | 236 | host_err = PTR_ERR(dentry); |
1da177e4 LT |
237 | if (IS_ERR(dentry)) |
238 | goto out_nfserr; | |
82ead7fe | 239 | if (nfsd_mountpoint(dentry, exp)) { |
bbddca8e N |
240 | /* |
241 | * We don't need the i_mutex after all. It's | |
242 | * still possible we could open this (regular | |
243 | * files can be mountpoints too), but the | |
244 | * i_mutex is just there to prevent renames of | |
245 | * something that we might be about to delegate, | |
246 | * and a mountpoint won't be renamed: | |
247 | */ | |
248 | fh_unlock(fhp); | |
6264d69d | 249 | if ((host_err = nfsd_cross_mnt(rqstp, &dentry, &exp))) { |
1da177e4 LT |
250 | dput(dentry); |
251 | goto out_nfserr; | |
252 | } | |
253 | } | |
254 | } | |
6c0a654d BF |
255 | *dentry_ret = dentry; |
256 | *exp_ret = exp; | |
257 | return 0; | |
258 | ||
259 | out_nfserr: | |
260 | exp_put(exp); | |
261 | return nfserrno(host_err); | |
262 | } | |
263 | ||
264 | /* | |
265 | * Look up one component of a pathname. | |
266 | * N.B. After this call _both_ fhp and resfh need an fh_put | |
267 | * | |
268 | * If the lookup would cross a mountpoint, and the mounted filesystem | |
269 | * is exported to the client with NFSEXP_NOHIDE, then the lookup is | |
270 | * accepted as it stands and the mounted directory is | |
271 | * returned. Otherwise the covered directory is returned. | |
272 | * NOTE: this mountpoint crossing is not supported properly by all | |
273 | * clients and is explicitly disallowed for NFSv3 | |
274 | * NeilBrown <neilb@cse.unsw.edu.au> | |
275 | */ | |
276 | __be32 | |
277 | nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name, | |
5a022fc8 | 278 | unsigned int len, struct svc_fh *resfh) |
6c0a654d BF |
279 | { |
280 | struct svc_export *exp; | |
281 | struct dentry *dentry; | |
282 | __be32 err; | |
283 | ||
29a78a3e BF |
284 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); |
285 | if (err) | |
286 | return err; | |
6c0a654d BF |
287 | err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry); |
288 | if (err) | |
289 | return err; | |
32c1eb0c AA |
290 | err = check_nfsd_access(exp, rqstp); |
291 | if (err) | |
292 | goto out; | |
1da177e4 LT |
293 | /* |
294 | * Note: we compose the file handle now, but as the | |
295 | * dentry may be negative, it may need to be updated. | |
296 | */ | |
297 | err = fh_compose(resfh, exp, dentry, fhp); | |
2b0143b5 | 298 | if (!err && d_really_is_negative(dentry)) |
1da177e4 | 299 | err = nfserr_noent; |
32c1eb0c | 300 | out: |
1da177e4 | 301 | dput(dentry); |
1da177e4 LT |
302 | exp_put(exp); |
303 | return err; | |
1da177e4 LT |
304 | } |
305 | ||
f501912a BM |
306 | /* |
307 | * Commit metadata changes to stable storage. | |
308 | */ | |
309 | static int | |
310 | commit_metadata(struct svc_fh *fhp) | |
311 | { | |
2b0143b5 | 312 | struct inode *inode = d_inode(fhp->fh_dentry); |
f501912a | 313 | const struct export_operations *export_ops = inode->i_sb->s_export_op; |
f501912a BM |
314 | |
315 | if (!EX_ISSYNC(fhp->fh_export)) | |
316 | return 0; | |
317 | ||
c3765016 CH |
318 | if (export_ops->commit_metadata) |
319 | return export_ops->commit_metadata(inode); | |
320 | return sync_inode_metadata(inode, 1); | |
f501912a | 321 | } |
6c0a654d | 322 | |
1da177e4 | 323 | /* |
818e5a22 CH |
324 | * Go over the attributes and take care of the small differences between |
325 | * NFS semantics and what Linux expects. | |
1da177e4 | 326 | */ |
818e5a22 CH |
327 | static void |
328 | nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap) | |
1da177e4 | 329 | { |
ca456252 | 330 | /* sanitize the mode change */ |
1da177e4 LT |
331 | if (iap->ia_valid & ATTR_MODE) { |
332 | iap->ia_mode &= S_IALLUGO; | |
dee3209d | 333 | iap->ia_mode |= (inode->i_mode & ~S_IALLUGO); |
ca456252 JL |
334 | } |
335 | ||
336 | /* Revoke setuid/setgid on chown */ | |
0953e620 | 337 | if (!S_ISDIR(inode->i_mode) && |
c4fa6d7c | 338 | ((iap->ia_valid & ATTR_UID) || (iap->ia_valid & ATTR_GID))) { |
ca456252 JL |
339 | iap->ia_valid |= ATTR_KILL_PRIV; |
340 | if (iap->ia_valid & ATTR_MODE) { | |
341 | /* we're setting mode too, just clear the s*id bits */ | |
8a0ce7d9 | 342 | iap->ia_mode &= ~S_ISUID; |
ca456252 JL |
343 | if (iap->ia_mode & S_IXGRP) |
344 | iap->ia_mode &= ~S_ISGID; | |
345 | } else { | |
346 | /* set ATTR_KILL_* bits and let VFS handle it */ | |
347 | iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID); | |
8a0ce7d9 | 348 | } |
1da177e4 | 349 | } |
818e5a22 CH |
350 | } |
351 | ||
0839ffb8 BF |
352 | static __be32 |
353 | nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
354 | struct iattr *iap) | |
355 | { | |
356 | struct inode *inode = d_inode(fhp->fh_dentry); | |
357 | int host_err; | |
358 | ||
359 | if (iap->ia_size < inode->i_size) { | |
360 | __be32 err; | |
361 | ||
362 | err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry, | |
363 | NFSD_MAY_TRUNC | NFSD_MAY_OWNER_OVERRIDE); | |
364 | if (err) | |
365 | return err; | |
366 | } | |
367 | ||
368 | host_err = get_write_access(inode); | |
369 | if (host_err) | |
370 | goto out_nfserrno; | |
371 | ||
372 | host_err = locks_verify_truncate(inode, NULL, iap->ia_size); | |
373 | if (host_err) | |
374 | goto out_put_write_access; | |
375 | return 0; | |
376 | ||
377 | out_put_write_access: | |
378 | put_write_access(inode); | |
379 | out_nfserrno: | |
380 | return nfserrno(host_err); | |
381 | } | |
382 | ||
818e5a22 CH |
383 | /* |
384 | * Set various file attributes. After this call fhp needs an fh_put. | |
385 | */ | |
386 | __be32 | |
387 | nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, | |
388 | int check_guard, time_t guardtime) | |
389 | { | |
390 | struct dentry *dentry; | |
391 | struct inode *inode; | |
392 | int accmode = NFSD_MAY_SATTR; | |
393 | umode_t ftype = 0; | |
394 | __be32 err; | |
395 | int host_err; | |
9f67f189 | 396 | bool get_write_count; |
758e99fe | 397 | bool size_change = (iap->ia_valid & ATTR_SIZE); |
818e5a22 CH |
398 | |
399 | if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) | |
400 | accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE; | |
401 | if (iap->ia_valid & ATTR_SIZE) | |
402 | ftype = S_IFREG; | |
403 | ||
9f67f189 BF |
404 | /* Callers that do fh_verify should do the fh_want_write: */ |
405 | get_write_count = !fhp->fh_dentry; | |
406 | ||
818e5a22 CH |
407 | /* Get inode */ |
408 | err = fh_verify(rqstp, fhp, ftype, accmode); | |
409 | if (err) | |
758e99fe | 410 | return err; |
9f67f189 BF |
411 | if (get_write_count) { |
412 | host_err = fh_want_write(fhp); | |
413 | if (host_err) | |
758e99fe | 414 | goto out; |
9f67f189 | 415 | } |
818e5a22 CH |
416 | |
417 | dentry = fhp->fh_dentry; | |
2b0143b5 | 418 | inode = d_inode(dentry); |
818e5a22 CH |
419 | |
420 | /* Ignore any mode updates on symlinks */ | |
421 | if (S_ISLNK(inode->i_mode)) | |
422 | iap->ia_valid &= ~ATTR_MODE; | |
423 | ||
424 | if (!iap->ia_valid) | |
758e99fe | 425 | return 0; |
1da177e4 | 426 | |
818e5a22 CH |
427 | nfsd_sanitize_attrs(inode, iap); |
428 | ||
758e99fe CH |
429 | if (check_guard && guardtime != inode->i_ctime.tv_sec) |
430 | return nfserr_notsync; | |
431 | ||
818e5a22 CH |
432 | /* |
433 | * The size case is special, it changes the file in addition to the | |
783112f7 CH |
434 | * attributes, and file systems don't expect it to be mixed with |
435 | * "random" attribute changes. We thus split out the size change | |
436 | * into a separate call to ->setattr, and do the rest as a separate | |
437 | * setattr call. | |
818e5a22 | 438 | */ |
758e99fe | 439 | if (size_change) { |
0839ffb8 BF |
440 | err = nfsd_get_write_access(rqstp, fhp, iap); |
441 | if (err) | |
758e99fe | 442 | return err; |
783112f7 | 443 | } |
f0c63124 | 444 | |
783112f7 CH |
445 | fh_lock(fhp); |
446 | if (size_change) { | |
f0c63124 | 447 | /* |
0839ffb8 BF |
448 | * RFC5661, Section 18.30.4: |
449 | * Changing the size of a file with SETATTR indirectly | |
450 | * changes the time_modify and change attributes. | |
451 | * | |
452 | * (and similar for the older RFCs) | |
f0c63124 | 453 | */ |
783112f7 CH |
454 | struct iattr size_attr = { |
455 | .ia_valid = ATTR_SIZE | ATTR_CTIME | ATTR_MTIME, | |
456 | .ia_size = iap->ia_size, | |
457 | }; | |
458 | ||
459 | host_err = notify_change(dentry, &size_attr, NULL); | |
460 | if (host_err) | |
461 | goto out_unlock; | |
462 | iap->ia_valid &= ~ATTR_SIZE; | |
463 | ||
464 | /* | |
465 | * Avoid the additional setattr call below if the only other | |
466 | * attribute that the client sends is the mtime, as we update | |
467 | * it as part of the size change above. | |
468 | */ | |
469 | if ((iap->ia_valid & ~ATTR_MTIME) == 0) | |
470 | goto out_unlock; | |
1da177e4 | 471 | } |
987da479 | 472 | |
41f53350 | 473 | iap->ia_valid |= ATTR_CTIME; |
987da479 | 474 | host_err = notify_change(dentry, iap, NULL); |
987da479 | 475 | |
783112f7 CH |
476 | out_unlock: |
477 | fh_unlock(fhp); | |
0839ffb8 BF |
478 | if (size_change) |
479 | put_write_access(inode); | |
0839ffb8 | 480 | out: |
758e99fe CH |
481 | if (!host_err) |
482 | host_err = commit_metadata(fhp); | |
483 | return nfserrno(host_err); | |
1da177e4 LT |
484 | } |
485 | ||
5be196e5 | 486 | #if defined(CONFIG_NFSD_V4) |
9b4146e8 CL |
487 | /* |
488 | * NFS junction information is stored in an extended attribute. | |
489 | */ | |
490 | #define NFSD_JUNCTION_XATTR_NAME XATTR_TRUSTED_PREFIX "junction.nfs" | |
491 | ||
492 | /** | |
493 | * nfsd4_is_junction - Test if an object could be an NFS junction | |
494 | * | |
495 | * @dentry: object to test | |
496 | * | |
497 | * Returns 1 if "dentry" appears to contain NFS junction information. | |
498 | * Otherwise 0 is returned. | |
499 | */ | |
11fcee02 TM |
500 | int nfsd4_is_junction(struct dentry *dentry) |
501 | { | |
2b0143b5 | 502 | struct inode *inode = d_inode(dentry); |
11fcee02 TM |
503 | |
504 | if (inode == NULL) | |
505 | return 0; | |
506 | if (inode->i_mode & S_IXUGO) | |
507 | return 0; | |
508 | if (!(inode->i_mode & S_ISVTX)) | |
509 | return 0; | |
9b4146e8 | 510 | if (vfs_getxattr(dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0) |
11fcee02 TM |
511 | return 0; |
512 | return 1; | |
513 | } | |
18032ca0 DQ |
514 | #ifdef CONFIG_NFSD_V4_SECURITY_LABEL |
515 | __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
516 | struct xdr_netobj *label) | |
517 | { | |
518 | __be32 error; | |
519 | int host_error; | |
520 | struct dentry *dentry; | |
521 | ||
522 | error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR); | |
523 | if (error) | |
524 | return error; | |
525 | ||
526 | dentry = fhp->fh_dentry; | |
527 | ||
5955102c | 528 | inode_lock(d_inode(dentry)); |
18032ca0 | 529 | host_error = security_inode_setsecctx(dentry, label->data, label->len); |
5955102c | 530 | inode_unlock(d_inode(dentry)); |
18032ca0 DQ |
531 | return nfserrno(host_error); |
532 | } | |
533 | #else | |
534 | __be32 nfsd4_set_nfs4_label(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
535 | struct xdr_netobj *label) | |
536 | { | |
537 | return nfserr_notsupp; | |
538 | } | |
539 | #endif | |
540 | ||
ffa0160a CH |
541 | __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst, |
542 | u64 dst_pos, u64 count) | |
543 | { | |
42ec3d4c DW |
544 | loff_t cloned; |
545 | ||
546 | cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count); | |
547 | if (count && cloned != count) | |
548 | cloned = -EINVAL; | |
549 | return nfserrno(cloned < 0 ? cloned : 0); | |
ffa0160a CH |
550 | } |
551 | ||
29ae7f9d AS |
552 | ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst, |
553 | u64 dst_pos, u64 count) | |
554 | { | |
555 | ||
556 | /* | |
557 | * Limit copy to 4MB to prevent indefinitely blocking an nfsd | |
558 | * thread and client rpc slot. The choice of 4MB is somewhat | |
559 | * arbitrary. We might instead base this on r/wsize, or make it | |
560 | * tunable, or use a time instead of a byte limit, or implement | |
561 | * asynchronous copy. In theory a client could also recognize a | |
562 | * limit like this and pipeline multiple COPY requests. | |
563 | */ | |
564 | count = min_t(u64, count, 1 << 22); | |
565 | return vfs_copy_file_range(src, src_pos, dst, dst_pos, count, 0); | |
566 | } | |
567 | ||
95d871f0 AS |
568 | __be32 nfsd4_vfs_fallocate(struct svc_rqst *rqstp, struct svc_fh *fhp, |
569 | struct file *file, loff_t offset, loff_t len, | |
570 | int flags) | |
571 | { | |
95d871f0 AS |
572 | int error; |
573 | ||
574 | if (!S_ISREG(file_inode(file)->i_mode)) | |
575 | return nfserr_inval; | |
576 | ||
95d871f0 AS |
577 | error = vfs_fallocate(file, flags, offset, len); |
578 | if (!error) | |
579 | error = commit_metadata(fhp); | |
580 | ||
581 | return nfserrno(error); | |
582 | } | |
6a85d6c7 | 583 | #endif /* defined(CONFIG_NFSD_V4) */ |
1da177e4 LT |
584 | |
585 | #ifdef CONFIG_NFSD_V3 | |
586 | /* | |
587 | * Check server access rights to a file system object | |
588 | */ | |
589 | struct accessmap { | |
590 | u32 access; | |
591 | int how; | |
592 | }; | |
593 | static struct accessmap nfs3_regaccess[] = { | |
8837abca MS |
594 | { NFS3_ACCESS_READ, NFSD_MAY_READ }, |
595 | { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC }, | |
596 | { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_TRUNC }, | |
597 | { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE }, | |
1da177e4 LT |
598 | |
599 | { 0, 0 } | |
600 | }; | |
601 | ||
602 | static struct accessmap nfs3_diraccess[] = { | |
8837abca MS |
603 | { NFS3_ACCESS_READ, NFSD_MAY_READ }, |
604 | { NFS3_ACCESS_LOOKUP, NFSD_MAY_EXEC }, | |
605 | { NFS3_ACCESS_MODIFY, NFSD_MAY_EXEC|NFSD_MAY_WRITE|NFSD_MAY_TRUNC}, | |
606 | { NFS3_ACCESS_EXTEND, NFSD_MAY_EXEC|NFSD_MAY_WRITE }, | |
607 | { NFS3_ACCESS_DELETE, NFSD_MAY_REMOVE }, | |
1da177e4 LT |
608 | |
609 | { 0, 0 } | |
610 | }; | |
611 | ||
612 | static struct accessmap nfs3_anyaccess[] = { | |
613 | /* Some clients - Solaris 2.6 at least, make an access call | |
614 | * to the server to check for access for things like /dev/null | |
615 | * (which really, the server doesn't care about). So | |
616 | * We provide simple access checking for them, looking | |
617 | * mainly at mode bits, and we make sure to ignore read-only | |
618 | * filesystem checks | |
619 | */ | |
8837abca MS |
620 | { NFS3_ACCESS_READ, NFSD_MAY_READ }, |
621 | { NFS3_ACCESS_EXECUTE, NFSD_MAY_EXEC }, | |
622 | { NFS3_ACCESS_MODIFY, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS }, | |
623 | { NFS3_ACCESS_EXTEND, NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS }, | |
1da177e4 LT |
624 | |
625 | { 0, 0 } | |
626 | }; | |
627 | ||
6264d69d | 628 | __be32 |
1da177e4 LT |
629 | nfsd_access(struct svc_rqst *rqstp, struct svc_fh *fhp, u32 *access, u32 *supported) |
630 | { | |
631 | struct accessmap *map; | |
632 | struct svc_export *export; | |
633 | struct dentry *dentry; | |
634 | u32 query, result = 0, sresult = 0; | |
6264d69d | 635 | __be32 error; |
1da177e4 | 636 | |
8837abca | 637 | error = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP); |
1da177e4 LT |
638 | if (error) |
639 | goto out; | |
640 | ||
641 | export = fhp->fh_export; | |
642 | dentry = fhp->fh_dentry; | |
643 | ||
e36cb0b8 | 644 | if (d_is_reg(dentry)) |
1da177e4 | 645 | map = nfs3_regaccess; |
e36cb0b8 | 646 | else if (d_is_dir(dentry)) |
1da177e4 LT |
647 | map = nfs3_diraccess; |
648 | else | |
649 | map = nfs3_anyaccess; | |
650 | ||
651 | ||
652 | query = *access; | |
653 | for (; map->access; map++) { | |
654 | if (map->access & query) { | |
6264d69d | 655 | __be32 err2; |
1da177e4 LT |
656 | |
657 | sresult |= map->access; | |
658 | ||
0ec757df | 659 | err2 = nfsd_permission(rqstp, export, dentry, map->how); |
1da177e4 LT |
660 | switch (err2) { |
661 | case nfs_ok: | |
662 | result |= map->access; | |
663 | break; | |
664 | ||
665 | /* the following error codes just mean the access was not allowed, | |
666 | * rather than an error occurred */ | |
667 | case nfserr_rofs: | |
668 | case nfserr_acces: | |
669 | case nfserr_perm: | |
670 | /* simply don't "or" in the access bit. */ | |
671 | break; | |
672 | default: | |
673 | error = err2; | |
674 | goto out; | |
675 | } | |
676 | } | |
677 | } | |
678 | *access = result; | |
679 | if (supported) | |
680 | *supported = sresult; | |
681 | ||
682 | out: | |
683 | return error; | |
684 | } | |
685 | #endif /* CONFIG_NFSD_V3 */ | |
686 | ||
105f4622 BF |
687 | static int nfsd_open_break_lease(struct inode *inode, int access) |
688 | { | |
689 | unsigned int mode; | |
1da177e4 | 690 | |
105f4622 BF |
691 | if (access & NFSD_MAY_NOT_BREAK_LEASE) |
692 | return 0; | |
693 | mode = (access & NFSD_MAY_WRITE) ? O_WRONLY : O_RDONLY; | |
694 | return break_lease(inode, mode | O_NONBLOCK); | |
695 | } | |
1da177e4 LT |
696 | |
697 | /* | |
698 | * Open an existing file or directory. | |
999448a8 BS |
699 | * The may_flags argument indicates the type of open (read/write/lock) |
700 | * and additional flags. | |
1da177e4 LT |
701 | * N.B. After this call fhp needs an fh_put |
702 | */ | |
6264d69d | 703 | __be32 |
175a4eb7 | 704 | nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, |
999448a8 | 705 | int may_flags, struct file **filp) |
1da177e4 | 706 | { |
765927b2 | 707 | struct path path; |
1da177e4 | 708 | struct inode *inode; |
8519f994 | 709 | struct file *file; |
6264d69d AV |
710 | int flags = O_RDONLY|O_LARGEFILE; |
711 | __be32 err; | |
91885258 | 712 | int host_err = 0; |
1da177e4 | 713 | |
e0e81739 DH |
714 | validate_process_creds(); |
715 | ||
1da177e4 LT |
716 | /* |
717 | * If we get here, then the client has already done an "open", | |
718 | * and (hopefully) checked permission - so allow OWNER_OVERRIDE | |
719 | * in case a chmod has now revoked permission. | |
d91d0b56 BF |
720 | * |
721 | * Arguably we should also allow the owner override for | |
722 | * directories, but we never have and it doesn't seem to have | |
723 | * caused anyone a problem. If we were to change this, note | |
724 | * also that our filldir callbacks would need a variant of | |
725 | * lookup_one_len that doesn't check permissions. | |
1da177e4 | 726 | */ |
d91d0b56 BF |
727 | if (type == S_IFREG) |
728 | may_flags |= NFSD_MAY_OWNER_OVERRIDE; | |
729 | err = fh_verify(rqstp, fhp, type, may_flags); | |
1da177e4 LT |
730 | if (err) |
731 | goto out; | |
732 | ||
765927b2 AV |
733 | path.mnt = fhp->fh_export->ex_path.mnt; |
734 | path.dentry = fhp->fh_dentry; | |
2b0143b5 | 735 | inode = d_inode(path.dentry); |
1da177e4 LT |
736 | |
737 | /* Disallow write access to files with the append-only bit set | |
738 | * or any access when mandatory locking enabled | |
739 | */ | |
740 | err = nfserr_perm; | |
999448a8 | 741 | if (IS_APPEND(inode) && (may_flags & NFSD_MAY_WRITE)) |
1da177e4 | 742 | goto out; |
5e7fc436 BF |
743 | /* |
744 | * We must ignore files (but only files) which might have mandatory | |
745 | * locks on them because there is no way to know if the accesser has | |
746 | * the lock. | |
747 | */ | |
748 | if (S_ISREG((inode)->i_mode) && mandatory_lock(inode)) | |
1da177e4 LT |
749 | goto out; |
750 | ||
751 | if (!inode->i_fop) | |
752 | goto out; | |
753 | ||
999448a8 | 754 | host_err = nfsd_open_break_lease(inode, may_flags); |
6264d69d | 755 | if (host_err) /* NOMEM or WOULDBLOCK */ |
1da177e4 LT |
756 | goto out_nfserr; |
757 | ||
999448a8 BS |
758 | if (may_flags & NFSD_MAY_WRITE) { |
759 | if (may_flags & NFSD_MAY_READ) | |
9ecb6a08 BF |
760 | flags = O_RDWR|O_LARGEFILE; |
761 | else | |
762 | flags = O_WRONLY|O_LARGEFILE; | |
1da177e4 | 763 | } |
999448a8 | 764 | |
8519f994 KM |
765 | file = dentry_open(&path, flags, current_cred()); |
766 | if (IS_ERR(file)) { | |
767 | host_err = PTR_ERR(file); | |
768 | goto out_nfserr; | |
769 | } | |
770 | ||
6035a27b | 771 | host_err = ima_file_check(file, may_flags); |
8519f994 | 772 | if (host_err) { |
fd891454 | 773 | fput(file); |
8519f994 | 774 | goto out_nfserr; |
06effdbb BS |
775 | } |
776 | ||
8519f994 KM |
777 | if (may_flags & NFSD_MAY_64BIT_COOKIE) |
778 | file->f_mode |= FMODE_64BITHASH; | |
779 | else | |
780 | file->f_mode |= FMODE_32BITHASH; | |
781 | ||
782 | *filp = file; | |
1da177e4 | 783 | out_nfserr: |
6264d69d | 784 | err = nfserrno(host_err); |
1da177e4 | 785 | out: |
e0e81739 | 786 | validate_process_creds(); |
1da177e4 LT |
787 | return err; |
788 | } | |
789 | ||
e749a462 CH |
790 | struct raparms * |
791 | nfsd_init_raparms(struct file *file) | |
1da177e4 | 792 | { |
e749a462 CH |
793 | struct inode *inode = file_inode(file); |
794 | dev_t dev = inode->i_sb->s_dev; | |
795 | ino_t ino = inode->i_ino; | |
1da177e4 LT |
796 | struct raparms *ra, **rap, **frap = NULL; |
797 | int depth = 0; | |
fce1456a GB |
798 | unsigned int hash; |
799 | struct raparm_hbucket *rab; | |
800 | ||
801 | hash = jhash_2words(dev, ino, 0xfeedbeef) & RAPARM_HASH_MASK; | |
802 | rab = &raparm_hash[hash]; | |
1da177e4 | 803 | |
fce1456a GB |
804 | spin_lock(&rab->pb_lock); |
805 | for (rap = &rab->pb_head; (ra = *rap); rap = &ra->p_next) { | |
1da177e4 LT |
806 | if (ra->p_ino == ino && ra->p_dev == dev) |
807 | goto found; | |
808 | depth++; | |
809 | if (ra->p_count == 0) | |
810 | frap = rap; | |
811 | } | |
3aa6e0aa | 812 | depth = nfsdstats.ra_size; |
1da177e4 | 813 | if (!frap) { |
fce1456a | 814 | spin_unlock(&rab->pb_lock); |
1da177e4 LT |
815 | return NULL; |
816 | } | |
817 | rap = frap; | |
818 | ra = *frap; | |
819 | ra->p_dev = dev; | |
820 | ra->p_ino = ino; | |
821 | ra->p_set = 0; | |
fce1456a | 822 | ra->p_hindex = hash; |
1da177e4 | 823 | found: |
fce1456a | 824 | if (rap != &rab->pb_head) { |
1da177e4 | 825 | *rap = ra->p_next; |
fce1456a GB |
826 | ra->p_next = rab->pb_head; |
827 | rab->pb_head = ra; | |
1da177e4 LT |
828 | } |
829 | ra->p_count++; | |
830 | nfsdstats.ra_depth[depth*10/nfsdstats.ra_size]++; | |
fce1456a | 831 | spin_unlock(&rab->pb_lock); |
e749a462 CH |
832 | |
833 | if (ra->p_set) | |
834 | file->f_ra = ra->p_ra; | |
1da177e4 LT |
835 | return ra; |
836 | } | |
837 | ||
e749a462 CH |
838 | void nfsd_put_raparams(struct file *file, struct raparms *ra) |
839 | { | |
840 | struct raparm_hbucket *rab = &raparm_hash[ra->p_hindex]; | |
841 | ||
842 | spin_lock(&rab->pb_lock); | |
843 | ra->p_ra = file->f_ra; | |
844 | ra->p_set = 1; | |
845 | ra->p_count--; | |
846 | spin_unlock(&rab->pb_lock); | |
847 | } | |
848 | ||
1da177e4 | 849 | /* |
cf8208d0 JA |
850 | * Grab and keep cached pages associated with a file in the svc_rqst |
851 | * so that they can be passed to the network sendmsg/sendpage routines | |
852 | * directly. They will be released after the sending has completed. | |
1da177e4 LT |
853 | */ |
854 | static int | |
cf8208d0 JA |
855 | nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf, |
856 | struct splice_desc *sd) | |
1da177e4 | 857 | { |
cf8208d0 | 858 | struct svc_rqst *rqstp = sd->u.data; |
afc59400 | 859 | struct page **pp = rqstp->rq_next_page; |
cf8208d0 JA |
860 | struct page *page = buf->page; |
861 | size_t size; | |
cf8208d0 JA |
862 | |
863 | size = sd->len; | |
1da177e4 LT |
864 | |
865 | if (rqstp->rq_res.page_len == 0) { | |
866 | get_page(page); | |
afc59400 BF |
867 | put_page(*rqstp->rq_next_page); |
868 | *(rqstp->rq_next_page++) = page; | |
cf8208d0 | 869 | rqstp->rq_res.page_base = buf->offset; |
1da177e4 | 870 | rqstp->rq_res.page_len = size; |
44524359 | 871 | } else if (page != pp[-1]) { |
1da177e4 | 872 | get_page(page); |
afc59400 BF |
873 | if (*rqstp->rq_next_page) |
874 | put_page(*rqstp->rq_next_page); | |
875 | *(rqstp->rq_next_page++) = page; | |
1da177e4 | 876 | rqstp->rq_res.page_len += size; |
44524359 | 877 | } else |
1da177e4 | 878 | rqstp->rq_res.page_len += size; |
1da177e4 | 879 | |
1da177e4 LT |
880 | return size; |
881 | } | |
882 | ||
cf8208d0 JA |
883 | static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe, |
884 | struct splice_desc *sd) | |
885 | { | |
886 | return __splice_from_pipe(pipe, sd, nfsd_splice_actor); | |
887 | } | |
888 | ||
87c5942e CL |
889 | static __be32 nfsd_finish_read(struct svc_rqst *rqstp, struct svc_fh *fhp, |
890 | struct file *file, loff_t offset, | |
891 | unsigned long *count, int host_err) | |
1da177e4 | 892 | { |
6264d69d AV |
893 | if (host_err >= 0) { |
894 | nfsdstats.io_read += host_err; | |
895 | *count = host_err; | |
2a12a9d7 | 896 | fsnotify_access(file); |
87c5942e | 897 | trace_nfsd_read_io_done(rqstp, fhp, offset, *count); |
dc97618d | 898 | return 0; |
87c5942e CL |
899 | } else { |
900 | trace_nfsd_read_err(rqstp, fhp, offset, host_err); | |
dc97618d | 901 | return nfserrno(host_err); |
87c5942e | 902 | } |
dc97618d BF |
903 | } |
904 | ||
87c5942e CL |
905 | __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp, |
906 | struct file *file, loff_t offset, unsigned long *count) | |
dc97618d BF |
907 | { |
908 | struct splice_desc sd = { | |
909 | .len = 0, | |
910 | .total_len = *count, | |
911 | .pos = offset, | |
912 | .u.data = rqstp, | |
913 | }; | |
914 | int host_err; | |
915 | ||
87c5942e | 916 | trace_nfsd_read_splice(rqstp, fhp, offset, *count); |
dc97618d BF |
917 | rqstp->rq_next_page = rqstp->rq_respages + 1; |
918 | host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor); | |
87c5942e | 919 | return nfsd_finish_read(rqstp, fhp, file, offset, count, host_err); |
dc97618d BF |
920 | } |
921 | ||
87c5942e CL |
922 | __be32 nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp, |
923 | struct file *file, loff_t offset, | |
924 | struct kvec *vec, int vlen, unsigned long *count) | |
dc97618d | 925 | { |
73da852e | 926 | struct iov_iter iter; |
dc97618d BF |
927 | int host_err; |
928 | ||
87c5942e | 929 | trace_nfsd_read_vector(rqstp, fhp, offset, *count); |
73da852e CH |
930 | iov_iter_kvec(&iter, READ | ITER_KVEC, vec, vlen, *count); |
931 | host_err = vfs_iter_read(file, &iter, &offset, 0); | |
87c5942e | 932 | return nfsd_finish_read(rqstp, fhp, file, offset, count, host_err); |
1da177e4 LT |
933 | } |
934 | ||
d911df7b BF |
935 | /* |
936 | * Gathered writes: If another process is currently writing to the file, | |
937 | * there's a high chance this is another nfsd (triggered by a bulk write | |
938 | * from a client's biod). Rather than syncing the file with each write | |
939 | * request, we sleep for 10 msec. | |
940 | * | |
941 | * I don't know if this roughly approximates C. Juszak's idea of | |
942 | * gathered writes, but it's a nice and simple solution (IMHO), and it | |
943 | * seems to work:-) | |
944 | * | |
945 | * Note: we do this only in the NFSv2 case, since v3 and higher have a | |
946 | * better tool (separate unstable writes and commits) for solving this | |
947 | * problem. | |
948 | */ | |
949 | static int wait_for_concurrent_writes(struct file *file) | |
950 | { | |
496ad9aa | 951 | struct inode *inode = file_inode(file); |
d911df7b BF |
952 | static ino_t last_ino; |
953 | static dev_t last_dev; | |
954 | int err = 0; | |
955 | ||
956 | if (atomic_read(&inode->i_writecount) > 1 | |
957 | || (last_ino == inode->i_ino && last_dev == inode->i_sb->s_dev)) { | |
958 | dprintk("nfsd: write defer %d\n", task_pid_nr(current)); | |
959 | msleep(10); | |
960 | dprintk("nfsd: write resume %d\n", task_pid_nr(current)); | |
961 | } | |
962 | ||
963 | if (inode->i_state & I_DIRTY) { | |
964 | dprintk("nfsd: write sync %d\n", task_pid_nr(current)); | |
8018ab05 | 965 | err = vfs_fsync(file, 0); |
d911df7b BF |
966 | } |
967 | last_ino = inode->i_ino; | |
968 | last_dev = inode->i_sb->s_dev; | |
969 | return err; | |
970 | } | |
971 | ||
af90f707 | 972 | __be32 |
1da177e4 LT |
973 | nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, |
974 | loff_t offset, struct kvec *vec, int vlen, | |
54bbb7d2 | 975 | unsigned long *cnt, int stable) |
1da177e4 LT |
976 | { |
977 | struct svc_export *exp; | |
73da852e | 978 | struct iov_iter iter; |
d890be15 | 979 | __be32 nfserr; |
6264d69d | 980 | int host_err; |
48e03bc5 | 981 | int use_wgather; |
e49dbbf3 | 982 | loff_t pos = offset; |
8658452e | 983 | unsigned int pflags = current->flags; |
ddef7ed2 | 984 | rwf_t flags = 0; |
8658452e | 985 | |
d890be15 CL |
986 | trace_nfsd_write_opened(rqstp, fhp, offset, *cnt); |
987 | ||
7501cc2b | 988 | if (test_bit(RQ_LOCAL, &rqstp->rq_flags)) |
8658452e N |
989 | /* |
990 | * We want less throttling in balance_dirty_pages() | |
991 | * and shrink_inactive_list() so that nfs to | |
992 | * localhost doesn't cause nfsd to lock up due to all | |
993 | * the client's dirty pages or its congested queue. | |
994 | */ | |
995 | current->flags |= PF_LESS_THROTTLE; | |
1da177e4 | 996 | |
865d50b2 | 997 | exp = fhp->fh_export; |
48e03bc5 | 998 | use_wgather = (rqstp->rq_vers == 2) && EX_WGATHER(exp); |
1da177e4 | 999 | |
1da177e4 | 1000 | if (!EX_ISSYNC(exp)) |
54bbb7d2 | 1001 | stable = NFS_UNSTABLE; |
1da177e4 | 1002 | |
24368aad CH |
1003 | if (stable && !use_wgather) |
1004 | flags |= RWF_SYNC; | |
1005 | ||
73da852e CH |
1006 | iov_iter_kvec(&iter, WRITE | ITER_KVEC, vec, vlen, *cnt); |
1007 | host_err = vfs_iter_write(file, &iter, &pos, flags); | |
e4636d53 BF |
1008 | if (host_err < 0) |
1009 | goto out_nfserr; | |
d890be15 | 1010 | nfsdstats.io_write += *cnt; |
2a12a9d7 | 1011 | fsnotify_modify(file); |
1da177e4 | 1012 | |
24368aad CH |
1013 | if (stable && use_wgather) |
1014 | host_err = wait_for_concurrent_writes(file); | |
1da177e4 | 1015 | |
e4636d53 | 1016 | out_nfserr: |
d890be15 CL |
1017 | if (host_err >= 0) { |
1018 | trace_nfsd_write_io_done(rqstp, fhp, offset, *cnt); | |
1019 | nfserr = nfs_ok; | |
1020 | } else { | |
1021 | trace_nfsd_write_err(rqstp, fhp, offset, host_err); | |
1022 | nfserr = nfserrno(host_err); | |
1023 | } | |
7501cc2b | 1024 | if (test_bit(RQ_LOCAL, &rqstp->rq_flags)) |
717a94b5 | 1025 | current_restore_flags(pflags, PF_LESS_THROTTLE); |
d890be15 | 1026 | return nfserr; |
1da177e4 LT |
1027 | } |
1028 | ||
dc97618d BF |
1029 | /* |
1030 | * Read data from a file. count must contain the requested read count | |
1031 | * on entry. On return, *count contains the number of bytes actually read. | |
1032 | * N.B. After this call fhp needs an fh_put | |
1033 | */ | |
1034 | __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
1035 | loff_t offset, struct kvec *vec, int vlen, unsigned long *count) | |
1036 | { | |
1037 | struct file *file; | |
1038 | struct raparms *ra; | |
1039 | __be32 err; | |
1040 | ||
f394b62b | 1041 | trace_nfsd_read_start(rqstp, fhp, offset, *count); |
e749a462 | 1042 | err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file); |
dc97618d BF |
1043 | if (err) |
1044 | return err; | |
1045 | ||
e749a462 | 1046 | ra = nfsd_init_raparms(file); |
6e8b50d1 | 1047 | |
a4058c5b | 1048 | if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &rqstp->rq_flags)) |
87c5942e | 1049 | err = nfsd_splice_read(rqstp, fhp, file, offset, count); |
a4058c5b | 1050 | else |
87c5942e | 1051 | err = nfsd_readv(rqstp, fhp, file, offset, vec, vlen, count); |
6e8b50d1 | 1052 | |
e749a462 CH |
1053 | if (ra) |
1054 | nfsd_put_raparams(file, ra); | |
1055 | fput(file); | |
dc97618d | 1056 | |
f394b62b | 1057 | trace_nfsd_read_done(rqstp, fhp, offset, *count); |
6e8b50d1 | 1058 | |
fa0a2126 BF |
1059 | return err; |
1060 | } | |
1061 | ||
1da177e4 LT |
1062 | /* |
1063 | * Write data to a file. | |
1064 | * The stable flag requests synchronous writes. | |
1065 | * N.B. After this call fhp needs an fh_put | |
1066 | */ | |
6264d69d | 1067 | __be32 |
52e380e0 KM |
1068 | nfsd_write(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t offset, |
1069 | struct kvec *vec, int vlen, unsigned long *cnt, int stable) | |
1da177e4 | 1070 | { |
52e380e0 KM |
1071 | struct file *file = NULL; |
1072 | __be32 err = 0; | |
1da177e4 | 1073 | |
f394b62b | 1074 | trace_nfsd_write_start(rqstp, fhp, offset, *cnt); |
6e8b50d1 | 1075 | |
52e380e0 KM |
1076 | err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_WRITE, &file); |
1077 | if (err) | |
1078 | goto out; | |
1079 | ||
52e380e0 | 1080 | err = nfsd_vfs_write(rqstp, fhp, file, offset, vec, vlen, cnt, stable); |
52e380e0 | 1081 | fput(file); |
1da177e4 | 1082 | out: |
f394b62b | 1083 | trace_nfsd_write_done(rqstp, fhp, offset, *cnt); |
1da177e4 LT |
1084 | return err; |
1085 | } | |
1086 | ||
1087 | #ifdef CONFIG_NFSD_V3 | |
1088 | /* | |
1089 | * Commit all pending writes to stable storage. | |
aa696a6f TM |
1090 | * |
1091 | * Note: we only guarantee that data that lies within the range specified | |
1092 | * by the 'offset' and 'count' parameters will be synced. | |
1da177e4 LT |
1093 | * |
1094 | * Unfortunately we cannot lock the file to make sure we return full WCC | |
1095 | * data to the client, as locking happens lower down in the filesystem. | |
1096 | */ | |
6264d69d | 1097 | __be32 |
1da177e4 LT |
1098 | nfsd_commit(struct svc_rqst *rqstp, struct svc_fh *fhp, |
1099 | loff_t offset, unsigned long count) | |
1100 | { | |
1101 | struct file *file; | |
aa696a6f TM |
1102 | loff_t end = LLONG_MAX; |
1103 | __be32 err = nfserr_inval; | |
1da177e4 | 1104 | |
aa696a6f TM |
1105 | if (offset < 0) |
1106 | goto out; | |
1107 | if (count != 0) { | |
1108 | end = offset + (loff_t)count - 1; | |
1109 | if (end < offset) | |
1110 | goto out; | |
1111 | } | |
1da177e4 | 1112 | |
91885258 JL |
1113 | err = nfsd_open(rqstp, fhp, S_IFREG, |
1114 | NFSD_MAY_WRITE|NFSD_MAY_NOT_BREAK_LEASE, &file); | |
8837abca | 1115 | if (err) |
aa696a6f | 1116 | goto out; |
1da177e4 | 1117 | if (EX_ISSYNC(fhp->fh_export)) { |
8018ab05 | 1118 | int err2 = vfs_fsync_range(file, offset, end, 0); |
aa696a6f TM |
1119 | |
1120 | if (err2 != -EINVAL) | |
1121 | err = nfserrno(err2); | |
1122 | else | |
1da177e4 | 1123 | err = nfserr_notsupp; |
1da177e4 LT |
1124 | } |
1125 | ||
fd891454 | 1126 | fput(file); |
aa696a6f | 1127 | out: |
1da177e4 LT |
1128 | return err; |
1129 | } | |
1130 | #endif /* CONFIG_NFSD_V3 */ | |
1131 | ||
f2b0dee2 | 1132 | static __be32 |
5c002b3b BF |
1133 | nfsd_create_setattr(struct svc_rqst *rqstp, struct svc_fh *resfhp, |
1134 | struct iattr *iap) | |
1135 | { | |
1136 | /* | |
1137 | * Mode has already been set earlier in create: | |
1138 | */ | |
1139 | iap->ia_valid &= ~ATTR_MODE; | |
1140 | /* | |
1141 | * Setting uid/gid works only for root. Irix appears to | |
1142 | * send along the gid on create when it tries to implement | |
1143 | * setgid directories via NFS: | |
1144 | */ | |
6fab8779 | 1145 | if (!uid_eq(current_fsuid(), GLOBAL_ROOT_UID)) |
5c002b3b BF |
1146 | iap->ia_valid &= ~(ATTR_UID|ATTR_GID); |
1147 | if (iap->ia_valid) | |
1148 | return nfsd_setattr(rqstp, resfhp, iap, 0, (time_t)0); | |
0f3a24b4 | 1149 | /* Callers expect file metadata to be committed here */ |
722b620d | 1150 | return nfserrno(commit_metadata(resfhp)); |
5c002b3b BF |
1151 | } |
1152 | ||
4ac35c2f | 1153 | /* HPUX client sometimes creates a file in mode 000, and sets size to 0. |
1154 | * setting size to 0 may fail for some specific file systems by the permission | |
1155 | * checking which requires WRITE permission but the mode is 000. | |
1156 | * we ignore the resizing(to 0) on the just new created file, since the size is | |
1157 | * 0 after file created. | |
1158 | * | |
1159 | * call this only after vfs_create() is called. | |
1160 | * */ | |
1161 | static void | |
1162 | nfsd_check_ignore_resizing(struct iattr *iap) | |
1163 | { | |
1164 | if ((iap->ia_valid & ATTR_SIZE) && (iap->ia_size == 0)) | |
1165 | iap->ia_valid &= ~ATTR_SIZE; | |
1166 | } | |
1167 | ||
b44061d0 | 1168 | /* The parent directory should already be locked: */ |
6264d69d | 1169 | __be32 |
b44061d0 | 1170 | nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp, |
1da177e4 LT |
1171 | char *fname, int flen, struct iattr *iap, |
1172 | int type, dev_t rdev, struct svc_fh *resfhp) | |
1173 | { | |
2b118859 | 1174 | struct dentry *dentry, *dchild; |
1da177e4 | 1175 | struct inode *dirp; |
6264d69d | 1176 | __be32 err; |
5c002b3b | 1177 | __be32 err2; |
6264d69d | 1178 | int host_err; |
1da177e4 | 1179 | |
1da177e4 | 1180 | dentry = fhp->fh_dentry; |
2b0143b5 | 1181 | dirp = d_inode(dentry); |
1da177e4 | 1182 | |
b44061d0 BF |
1183 | dchild = dget(resfhp->fh_dentry); |
1184 | if (!fhp->fh_locked) { | |
1185 | WARN_ONCE(1, "nfsd_create: parent %pd2 not locked!\n", | |
a6a9f18f | 1186 | dentry); |
b44061d0 BF |
1187 | err = nfserr_io; |
1188 | goto out; | |
1da177e4 | 1189 | } |
1da177e4 | 1190 | |
7eed34f1 OD |
1191 | err = nfsd_permission(rqstp, fhp->fh_export, dentry, NFSD_MAY_CREATE); |
1192 | if (err) | |
1193 | goto out; | |
1194 | ||
1da177e4 LT |
1195 | if (!(iap->ia_valid & ATTR_MODE)) |
1196 | iap->ia_mode = 0; | |
1197 | iap->ia_mode = (iap->ia_mode & S_IALLUGO) | type; | |
1198 | ||
088406bc | 1199 | err = 0; |
4a55c101 | 1200 | host_err = 0; |
1da177e4 LT |
1201 | switch (type) { |
1202 | case S_IFREG: | |
312b63fb | 1203 | host_err = vfs_create(dirp, dchild, iap->ia_mode, true); |
4ac35c2f | 1204 | if (!host_err) |
1205 | nfsd_check_ignore_resizing(iap); | |
1da177e4 LT |
1206 | break; |
1207 | case S_IFDIR: | |
6264d69d | 1208 | host_err = vfs_mkdir(dirp, dchild, iap->ia_mode); |
3819bb0d AV |
1209 | if (!host_err && unlikely(d_unhashed(dchild))) { |
1210 | struct dentry *d; | |
1211 | d = lookup_one_len(dchild->d_name.name, | |
1212 | dchild->d_parent, | |
1213 | dchild->d_name.len); | |
1214 | if (IS_ERR(d)) { | |
1215 | host_err = PTR_ERR(d); | |
1216 | break; | |
1217 | } | |
1218 | if (unlikely(d_is_negative(d))) { | |
1219 | dput(d); | |
1220 | err = nfserr_serverfault; | |
1221 | goto out; | |
1222 | } | |
1223 | dput(resfhp->fh_dentry); | |
1224 | resfhp->fh_dentry = dget(d); | |
1225 | err = fh_update(resfhp); | |
1226 | dput(dchild); | |
1227 | dchild = d; | |
1228 | if (err) | |
1229 | goto out; | |
1230 | } | |
1da177e4 LT |
1231 | break; |
1232 | case S_IFCHR: | |
1233 | case S_IFBLK: | |
1234 | case S_IFIFO: | |
1235 | case S_IFSOCK: | |
6264d69d | 1236 | host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev); |
1da177e4 | 1237 | break; |
71423274 BF |
1238 | default: |
1239 | printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n", | |
1240 | type); | |
1241 | host_err = -EINVAL; | |
1da177e4 | 1242 | } |
4a55c101 | 1243 | if (host_err < 0) |
1da177e4 LT |
1244 | goto out_nfserr; |
1245 | ||
f501912a | 1246 | err = nfsd_create_setattr(rqstp, resfhp, iap); |
1da177e4 | 1247 | |
f501912a | 1248 | /* |
0f3a24b4 TM |
1249 | * nfsd_create_setattr already committed the child. Transactional |
1250 | * filesystems had a chance to commit changes for both parent and | |
b44061d0 | 1251 | * child simultaneously making the following commit_metadata a |
0f3a24b4 | 1252 | * noop. |
f501912a BM |
1253 | */ |
1254 | err2 = nfserrno(commit_metadata(fhp)); | |
5c002b3b BF |
1255 | if (err2) |
1256 | err = err2; | |
1da177e4 LT |
1257 | /* |
1258 | * Update the file handle to get the new inode info. | |
1259 | */ | |
1260 | if (!err) | |
1261 | err = fh_update(resfhp); | |
1262 | out: | |
2b118859 | 1263 | dput(dchild); |
1da177e4 LT |
1264 | return err; |
1265 | ||
1266 | out_nfserr: | |
6264d69d | 1267 | err = nfserrno(host_err); |
1da177e4 LT |
1268 | goto out; |
1269 | } | |
1270 | ||
b44061d0 BF |
1271 | /* |
1272 | * Create a filesystem object (regular, directory, special). | |
1273 | * Note that the parent directory is left locked. | |
1274 | * | |
1275 | * N.B. Every call to nfsd_create needs an fh_put for _both_ fhp and resfhp | |
1276 | */ | |
1277 | __be32 | |
1278 | nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, | |
1279 | char *fname, int flen, struct iattr *iap, | |
1280 | int type, dev_t rdev, struct svc_fh *resfhp) | |
1281 | { | |
1282 | struct dentry *dentry, *dchild = NULL; | |
1283 | struct inode *dirp; | |
1284 | __be32 err; | |
1285 | int host_err; | |
1286 | ||
1287 | if (isdotent(fname, flen)) | |
1288 | return nfserr_exist; | |
1289 | ||
fa08139d | 1290 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_NOP); |
b44061d0 BF |
1291 | if (err) |
1292 | return err; | |
1293 | ||
1294 | dentry = fhp->fh_dentry; | |
1295 | dirp = d_inode(dentry); | |
1296 | ||
1297 | host_err = fh_want_write(fhp); | |
1298 | if (host_err) | |
1299 | return nfserrno(host_err); | |
1300 | ||
1301 | fh_lock_nested(fhp, I_MUTEX_PARENT); | |
1302 | dchild = lookup_one_len(fname, dentry, flen); | |
1303 | host_err = PTR_ERR(dchild); | |
1304 | if (IS_ERR(dchild)) | |
1305 | return nfserrno(host_err); | |
1306 | err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); | |
502aa0a5 JB |
1307 | /* |
1308 | * We unconditionally drop our ref to dchild as fh_compose will have | |
1309 | * already grabbed its own ref for it. | |
1310 | */ | |
1311 | dput(dchild); | |
1312 | if (err) | |
b44061d0 | 1313 | return err; |
b44061d0 BF |
1314 | return nfsd_create_locked(rqstp, fhp, fname, flen, iap, type, |
1315 | rdev, resfhp); | |
1316 | } | |
1317 | ||
1da177e4 | 1318 | #ifdef CONFIG_NFSD_V3 |
ac6721a1 | 1319 | |
1da177e4 | 1320 | /* |
ac6721a1 | 1321 | * NFSv3 and NFSv4 version of nfsd_create |
1da177e4 | 1322 | */ |
6264d69d | 1323 | __be32 |
ac6721a1 | 1324 | do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, |
1da177e4 LT |
1325 | char *fname, int flen, struct iattr *iap, |
1326 | struct svc_fh *resfhp, int createmode, u32 *verifier, | |
856121b2 | 1327 | bool *truncp, bool *created) |
1da177e4 LT |
1328 | { |
1329 | struct dentry *dentry, *dchild = NULL; | |
1330 | struct inode *dirp; | |
6264d69d AV |
1331 | __be32 err; |
1332 | int host_err; | |
1da177e4 | 1333 | __u32 v_mtime=0, v_atime=0; |
1da177e4 LT |
1334 | |
1335 | err = nfserr_perm; | |
1336 | if (!flen) | |
1337 | goto out; | |
1338 | err = nfserr_exist; | |
1339 | if (isdotent(fname, flen)) | |
1340 | goto out; | |
1341 | if (!(iap->ia_valid & ATTR_MODE)) | |
1342 | iap->ia_mode = 0; | |
1574dff8 | 1343 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); |
1da177e4 LT |
1344 | if (err) |
1345 | goto out; | |
1346 | ||
1347 | dentry = fhp->fh_dentry; | |
2b0143b5 | 1348 | dirp = d_inode(dentry); |
1da177e4 | 1349 | |
4a55c101 JK |
1350 | host_err = fh_want_write(fhp); |
1351 | if (host_err) | |
1352 | goto out_nfserr; | |
1353 | ||
12fd3520 | 1354 | fh_lock_nested(fhp, I_MUTEX_PARENT); |
1da177e4 LT |
1355 | |
1356 | /* | |
1357 | * Compose the response file handle. | |
1358 | */ | |
1359 | dchild = lookup_one_len(fname, dentry, flen); | |
6264d69d | 1360 | host_err = PTR_ERR(dchild); |
1da177e4 LT |
1361 | if (IS_ERR(dchild)) |
1362 | goto out_nfserr; | |
1363 | ||
1574dff8 | 1364 | /* If file doesn't exist, check for permissions to create one */ |
2b0143b5 | 1365 | if (d_really_is_negative(dchild)) { |
1574dff8 SP |
1366 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); |
1367 | if (err) | |
1368 | goto out; | |
1369 | } | |
1370 | ||
1da177e4 LT |
1371 | err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); |
1372 | if (err) | |
1373 | goto out; | |
1374 | ||
ac6721a1 | 1375 | if (nfsd_create_is_exclusive(createmode)) { |
c397852c | 1376 | /* solaris7 gets confused (bugid 4218508) if these have |
749997e5 JL |
1377 | * the high bit set, so just clear the high bits. If this is |
1378 | * ever changed to use different attrs for storing the | |
1379 | * verifier, then do_open_lookup() will also need to be fixed | |
1380 | * accordingly. | |
1da177e4 LT |
1381 | */ |
1382 | v_mtime = verifier[0]&0x7fffffff; | |
1383 | v_atime = verifier[1]&0x7fffffff; | |
1da177e4 LT |
1384 | } |
1385 | ||
2b0143b5 | 1386 | if (d_really_is_positive(dchild)) { |
1da177e4 LT |
1387 | err = 0; |
1388 | ||
1389 | switch (createmode) { | |
1390 | case NFS3_CREATE_UNCHECKED: | |
e36cb0b8 | 1391 | if (! d_is_reg(dchild)) |
9dc4e6c4 | 1392 | goto out; |
1da177e4 LT |
1393 | else if (truncp) { |
1394 | /* in nfsv4, we need to treat this case a little | |
1395 | * differently. we don't want to truncate the | |
1396 | * file now; this would be wrong if the OPEN | |
1397 | * fails for some other reason. furthermore, | |
1398 | * if the size is nonzero, we should ignore it | |
1399 | * according to spec! | |
1400 | */ | |
1401 | *truncp = (iap->ia_valid & ATTR_SIZE) && !iap->ia_size; | |
1402 | } | |
1403 | else { | |
1404 | iap->ia_valid &= ATTR_SIZE; | |
1405 | goto set_attr; | |
1406 | } | |
1407 | break; | |
1408 | case NFS3_CREATE_EXCLUSIVE: | |
2b0143b5 DH |
1409 | if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime |
1410 | && d_inode(dchild)->i_atime.tv_sec == v_atime | |
1411 | && d_inode(dchild)->i_size == 0 ) { | |
7007c90f NB |
1412 | if (created) |
1413 | *created = 1; | |
1da177e4 | 1414 | break; |
7007c90f | 1415 | } |
ac6721a1 | 1416 | case NFS4_CREATE_EXCLUSIVE4_1: |
2b0143b5 DH |
1417 | if ( d_inode(dchild)->i_mtime.tv_sec == v_mtime |
1418 | && d_inode(dchild)->i_atime.tv_sec == v_atime | |
1419 | && d_inode(dchild)->i_size == 0 ) { | |
7007c90f NB |
1420 | if (created) |
1421 | *created = 1; | |
ac6721a1 | 1422 | goto set_attr; |
7007c90f | 1423 | } |
1da177e4 LT |
1424 | /* fallthru */ |
1425 | case NFS3_CREATE_GUARDED: | |
1426 | err = nfserr_exist; | |
1427 | } | |
bad0dcff | 1428 | fh_drop_write(fhp); |
1da177e4 LT |
1429 | goto out; |
1430 | } | |
1431 | ||
312b63fb | 1432 | host_err = vfs_create(dirp, dchild, iap->ia_mode, true); |
463c3197 | 1433 | if (host_err < 0) { |
bad0dcff | 1434 | fh_drop_write(fhp); |
1da177e4 | 1435 | goto out_nfserr; |
463c3197 | 1436 | } |
81ac95c5 BF |
1437 | if (created) |
1438 | *created = 1; | |
1da177e4 | 1439 | |
4ac35c2f | 1440 | nfsd_check_ignore_resizing(iap); |
1441 | ||
ac6721a1 | 1442 | if (nfsd_create_is_exclusive(createmode)) { |
c397852c | 1443 | /* Cram the verifier into atime/mtime */ |
1da177e4 | 1444 | iap->ia_valid = ATTR_MTIME|ATTR_ATIME |
c397852c | 1445 | | ATTR_MTIME_SET|ATTR_ATIME_SET; |
1da177e4 LT |
1446 | /* XXX someone who knows this better please fix it for nsec */ |
1447 | iap->ia_mtime.tv_sec = v_mtime; | |
1448 | iap->ia_atime.tv_sec = v_atime; | |
1449 | iap->ia_mtime.tv_nsec = 0; | |
1450 | iap->ia_atime.tv_nsec = 0; | |
1da177e4 LT |
1451 | } |
1452 | ||
1da177e4 | 1453 | set_attr: |
f501912a BM |
1454 | err = nfsd_create_setattr(rqstp, resfhp, iap); |
1455 | ||
1456 | /* | |
0f3a24b4 TM |
1457 | * nfsd_create_setattr already committed the child |
1458 | * (and possibly also the parent). | |
f501912a BM |
1459 | */ |
1460 | if (!err) | |
1461 | err = nfserrno(commit_metadata(fhp)); | |
f193fbab YT |
1462 | |
1463 | /* | |
1464 | * Update the filehandle to get the new inode info. | |
1465 | */ | |
1466 | if (!err) | |
1467 | err = fh_update(resfhp); | |
1da177e4 LT |
1468 | |
1469 | out: | |
1470 | fh_unlock(fhp); | |
1471 | if (dchild && !IS_ERR(dchild)) | |
1472 | dput(dchild); | |
4a55c101 | 1473 | fh_drop_write(fhp); |
1da177e4 LT |
1474 | return err; |
1475 | ||
1476 | out_nfserr: | |
6264d69d | 1477 | err = nfserrno(host_err); |
1da177e4 LT |
1478 | goto out; |
1479 | } | |
1480 | #endif /* CONFIG_NFSD_V3 */ | |
1481 | ||
1482 | /* | |
1483 | * Read a symlink. On entry, *lenp must contain the maximum path length that | |
1484 | * fits into the buffer. On return, it contains the true length. | |
1485 | * N.B. After this call fhp needs an fh_put | |
1486 | */ | |
6264d69d | 1487 | __be32 |
1da177e4 LT |
1488 | nfsd_readlink(struct svc_rqst *rqstp, struct svc_fh *fhp, char *buf, int *lenp) |
1489 | { | |
6264d69d | 1490 | __be32 err; |
4d7edbc3 | 1491 | const char *link; |
68ac1234 | 1492 | struct path path; |
4d7edbc3 AV |
1493 | DEFINE_DELAYED_CALL(done); |
1494 | int len; | |
1da177e4 | 1495 | |
8837abca | 1496 | err = fh_verify(rqstp, fhp, S_IFLNK, NFSD_MAY_NOP); |
4d7edbc3 AV |
1497 | if (unlikely(err)) |
1498 | return err; | |
1da177e4 | 1499 | |
68ac1234 AV |
1500 | path.mnt = fhp->fh_export->ex_path.mnt; |
1501 | path.dentry = fhp->fh_dentry; | |
1da177e4 | 1502 | |
4d7edbc3 AV |
1503 | if (unlikely(!d_is_symlink(path.dentry))) |
1504 | return nfserr_inval; | |
1da177e4 | 1505 | |
68ac1234 | 1506 | touch_atime(&path); |
1da177e4 | 1507 | |
4d7edbc3 AV |
1508 | link = vfs_get_link(path.dentry, &done); |
1509 | if (IS_ERR(link)) | |
1510 | return nfserrno(PTR_ERR(link)); | |
1da177e4 | 1511 | |
4d7edbc3 AV |
1512 | len = strlen(link); |
1513 | if (len < *lenp) | |
1514 | *lenp = len; | |
1515 | memcpy(buf, link, *lenp); | |
1516 | do_delayed_call(&done); | |
1517 | return 0; | |
1da177e4 LT |
1518 | } |
1519 | ||
1520 | /* | |
1521 | * Create a symlink and look up its inode | |
1522 | * N.B. After this call _both_ fhp and resfhp need an fh_put | |
1523 | */ | |
6264d69d | 1524 | __be32 |
1da177e4 LT |
1525 | nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp, |
1526 | char *fname, int flen, | |
52ee0433 | 1527 | char *path, |
1e444f5b | 1528 | struct svc_fh *resfhp) |
1da177e4 LT |
1529 | { |
1530 | struct dentry *dentry, *dnew; | |
6264d69d AV |
1531 | __be32 err, cerr; |
1532 | int host_err; | |
1da177e4 LT |
1533 | |
1534 | err = nfserr_noent; | |
52ee0433 | 1535 | if (!flen || path[0] == '\0') |
1da177e4 LT |
1536 | goto out; |
1537 | err = nfserr_exist; | |
1538 | if (isdotent(fname, flen)) | |
1539 | goto out; | |
1540 | ||
8837abca | 1541 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); |
1da177e4 LT |
1542 | if (err) |
1543 | goto out; | |
4a55c101 JK |
1544 | |
1545 | host_err = fh_want_write(fhp); | |
1546 | if (host_err) | |
1547 | goto out_nfserr; | |
1548 | ||
1da177e4 LT |
1549 | fh_lock(fhp); |
1550 | dentry = fhp->fh_dentry; | |
1551 | dnew = lookup_one_len(fname, dentry, flen); | |
6264d69d | 1552 | host_err = PTR_ERR(dnew); |
1da177e4 LT |
1553 | if (IS_ERR(dnew)) |
1554 | goto out_nfserr; | |
1555 | ||
2b0143b5 | 1556 | host_err = vfs_symlink(d_inode(dentry), dnew, path); |
6264d69d | 1557 | err = nfserrno(host_err); |
f501912a BM |
1558 | if (!err) |
1559 | err = nfserrno(commit_metadata(fhp)); | |
1da177e4 LT |
1560 | fh_unlock(fhp); |
1561 | ||
bad0dcff | 1562 | fh_drop_write(fhp); |
75c3f29d | 1563 | |
1da177e4 LT |
1564 | cerr = fh_compose(resfhp, fhp->fh_export, dnew, fhp); |
1565 | dput(dnew); | |
1566 | if (err==0) err = cerr; | |
1567 | out: | |
1568 | return err; | |
1569 | ||
1570 | out_nfserr: | |
6264d69d | 1571 | err = nfserrno(host_err); |
1da177e4 LT |
1572 | goto out; |
1573 | } | |
1574 | ||
1575 | /* | |
1576 | * Create a hardlink | |
1577 | * N.B. After this call _both_ ffhp and tfhp need an fh_put | |
1578 | */ | |
6264d69d | 1579 | __be32 |
1da177e4 LT |
1580 | nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp, |
1581 | char *name, int len, struct svc_fh *tfhp) | |
1582 | { | |
1583 | struct dentry *ddir, *dnew, *dold; | |
55b13354 | 1584 | struct inode *dirp; |
6264d69d AV |
1585 | __be32 err; |
1586 | int host_err; | |
1da177e4 | 1587 | |
8837abca | 1588 | err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE); |
1da177e4 LT |
1589 | if (err) |
1590 | goto out; | |
7d818a7b | 1591 | err = fh_verify(rqstp, tfhp, 0, NFSD_MAY_NOP); |
1da177e4 LT |
1592 | if (err) |
1593 | goto out; | |
7d818a7b | 1594 | err = nfserr_isdir; |
e36cb0b8 | 1595 | if (d_is_dir(tfhp->fh_dentry)) |
7d818a7b | 1596 | goto out; |
1da177e4 LT |
1597 | err = nfserr_perm; |
1598 | if (!len) | |
1599 | goto out; | |
1600 | err = nfserr_exist; | |
1601 | if (isdotent(name, len)) | |
1602 | goto out; | |
1603 | ||
4a55c101 JK |
1604 | host_err = fh_want_write(tfhp); |
1605 | if (host_err) { | |
1606 | err = nfserrno(host_err); | |
1607 | goto out; | |
1608 | } | |
1609 | ||
12fd3520 | 1610 | fh_lock_nested(ffhp, I_MUTEX_PARENT); |
1da177e4 | 1611 | ddir = ffhp->fh_dentry; |
2b0143b5 | 1612 | dirp = d_inode(ddir); |
1da177e4 LT |
1613 | |
1614 | dnew = lookup_one_len(name, ddir, len); | |
6264d69d | 1615 | host_err = PTR_ERR(dnew); |
1da177e4 LT |
1616 | if (IS_ERR(dnew)) |
1617 | goto out_nfserr; | |
1618 | ||
1619 | dold = tfhp->fh_dentry; | |
1da177e4 | 1620 | |
4795bb37 | 1621 | err = nfserr_noent; |
2b0143b5 | 1622 | if (d_really_is_negative(dold)) |
4a55c101 | 1623 | goto out_dput; |
146a8595 | 1624 | host_err = vfs_link(dold, dirp, dnew, NULL); |
6264d69d | 1625 | if (!host_err) { |
f501912a BM |
1626 | err = nfserrno(commit_metadata(ffhp)); |
1627 | if (!err) | |
1628 | err = nfserrno(commit_metadata(tfhp)); | |
1da177e4 | 1629 | } else { |
6264d69d | 1630 | if (host_err == -EXDEV && rqstp->rq_vers == 2) |
1da177e4 LT |
1631 | err = nfserr_acces; |
1632 | else | |
6264d69d | 1633 | err = nfserrno(host_err); |
1da177e4 | 1634 | } |
75c3f29d | 1635 | out_dput: |
1da177e4 | 1636 | dput(dnew); |
270d56e5 DR |
1637 | out_unlock: |
1638 | fh_unlock(ffhp); | |
4a55c101 | 1639 | fh_drop_write(tfhp); |
1da177e4 LT |
1640 | out: |
1641 | return err; | |
1642 | ||
1643 | out_nfserr: | |
6264d69d | 1644 | err = nfserrno(host_err); |
270d56e5 | 1645 | goto out_unlock; |
1da177e4 LT |
1646 | } |
1647 | ||
1648 | /* | |
1649 | * Rename a file | |
1650 | * N.B. After this call _both_ ffhp and tfhp need an fh_put | |
1651 | */ | |
6264d69d | 1652 | __be32 |
1da177e4 LT |
1653 | nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, |
1654 | struct svc_fh *tfhp, char *tname, int tlen) | |
1655 | { | |
1656 | struct dentry *fdentry, *tdentry, *odentry, *ndentry, *trap; | |
1657 | struct inode *fdir, *tdir; | |
6264d69d AV |
1658 | __be32 err; |
1659 | int host_err; | |
1da177e4 | 1660 | |
8837abca | 1661 | err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE); |
1da177e4 LT |
1662 | if (err) |
1663 | goto out; | |
8837abca | 1664 | err = fh_verify(rqstp, tfhp, S_IFDIR, NFSD_MAY_CREATE); |
1da177e4 LT |
1665 | if (err) |
1666 | goto out; | |
1667 | ||
1668 | fdentry = ffhp->fh_dentry; | |
2b0143b5 | 1669 | fdir = d_inode(fdentry); |
1da177e4 LT |
1670 | |
1671 | tdentry = tfhp->fh_dentry; | |
2b0143b5 | 1672 | tdir = d_inode(tdentry); |
1da177e4 | 1673 | |
1da177e4 LT |
1674 | err = nfserr_perm; |
1675 | if (!flen || isdotent(fname, flen) || !tlen || isdotent(tname, tlen)) | |
1676 | goto out; | |
1677 | ||
4a55c101 JK |
1678 | host_err = fh_want_write(ffhp); |
1679 | if (host_err) { | |
1680 | err = nfserrno(host_err); | |
1681 | goto out; | |
1682 | } | |
1683 | ||
1da177e4 LT |
1684 | /* cannot use fh_lock as we need deadlock protective ordering |
1685 | * so do it by hand */ | |
1686 | trap = lock_rename(tdentry, fdentry); | |
aaf91ec1 | 1687 | ffhp->fh_locked = tfhp->fh_locked = true; |
1da177e4 LT |
1688 | fill_pre_wcc(ffhp); |
1689 | fill_pre_wcc(tfhp); | |
1690 | ||
1691 | odentry = lookup_one_len(fname, fdentry, flen); | |
6264d69d | 1692 | host_err = PTR_ERR(odentry); |
1da177e4 LT |
1693 | if (IS_ERR(odentry)) |
1694 | goto out_nfserr; | |
1695 | ||
6264d69d | 1696 | host_err = -ENOENT; |
2b0143b5 | 1697 | if (d_really_is_negative(odentry)) |
1da177e4 | 1698 | goto out_dput_old; |
6264d69d | 1699 | host_err = -EINVAL; |
1da177e4 LT |
1700 | if (odentry == trap) |
1701 | goto out_dput_old; | |
1702 | ||
1703 | ndentry = lookup_one_len(tname, tdentry, tlen); | |
6264d69d | 1704 | host_err = PTR_ERR(ndentry); |
1da177e4 LT |
1705 | if (IS_ERR(ndentry)) |
1706 | goto out_dput_old; | |
6264d69d | 1707 | host_err = -ENOTEMPTY; |
1da177e4 LT |
1708 | if (ndentry == trap) |
1709 | goto out_dput_new; | |
1710 | ||
9079b1eb DH |
1711 | host_err = -EXDEV; |
1712 | if (ffhp->fh_export->ex_path.mnt != tfhp->fh_export->ex_path.mnt) | |
1713 | goto out_dput_new; | |
aa387d6c BF |
1714 | if (ffhp->fh_export->ex_path.dentry != tfhp->fh_export->ex_path.dentry) |
1715 | goto out_dput_new; | |
9079b1eb | 1716 | |
520c8b16 | 1717 | host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL, 0); |
f501912a BM |
1718 | if (!host_err) { |
1719 | host_err = commit_metadata(tfhp); | |
6264d69d | 1720 | if (!host_err) |
f501912a | 1721 | host_err = commit_metadata(ffhp); |
1da177e4 | 1722 | } |
1da177e4 LT |
1723 | out_dput_new: |
1724 | dput(ndentry); | |
1725 | out_dput_old: | |
1726 | dput(odentry); | |
1727 | out_nfserr: | |
6264d69d | 1728 | err = nfserrno(host_err); |
fbb74a34 BF |
1729 | /* |
1730 | * We cannot rely on fh_unlock on the two filehandles, | |
1da177e4 | 1731 | * as that would do the wrong thing if the two directories |
fbb74a34 | 1732 | * were the same, so again we do it by hand. |
1da177e4 LT |
1733 | */ |
1734 | fill_post_wcc(ffhp); | |
1735 | fill_post_wcc(tfhp); | |
1736 | unlock_rename(tdentry, fdentry); | |
aaf91ec1 | 1737 | ffhp->fh_locked = tfhp->fh_locked = false; |
4a55c101 | 1738 | fh_drop_write(ffhp); |
1da177e4 LT |
1739 | |
1740 | out: | |
1741 | return err; | |
1742 | } | |
1743 | ||
1744 | /* | |
1745 | * Unlink a file or directory | |
1746 | * N.B. After this call fhp needs an fh_put | |
1747 | */ | |
6264d69d | 1748 | __be32 |
1da177e4 LT |
1749 | nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, |
1750 | char *fname, int flen) | |
1751 | { | |
1752 | struct dentry *dentry, *rdentry; | |
1753 | struct inode *dirp; | |
6264d69d AV |
1754 | __be32 err; |
1755 | int host_err; | |
1da177e4 LT |
1756 | |
1757 | err = nfserr_acces; | |
1758 | if (!flen || isdotent(fname, flen)) | |
1759 | goto out; | |
8837abca | 1760 | err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_REMOVE); |
1da177e4 LT |
1761 | if (err) |
1762 | goto out; | |
1763 | ||
4a55c101 JK |
1764 | host_err = fh_want_write(fhp); |
1765 | if (host_err) | |
1766 | goto out_nfserr; | |
1767 | ||
12fd3520 | 1768 | fh_lock_nested(fhp, I_MUTEX_PARENT); |
1da177e4 | 1769 | dentry = fhp->fh_dentry; |
2b0143b5 | 1770 | dirp = d_inode(dentry); |
1da177e4 LT |
1771 | |
1772 | rdentry = lookup_one_len(fname, dentry, flen); | |
6264d69d | 1773 | host_err = PTR_ERR(rdentry); |
1da177e4 LT |
1774 | if (IS_ERR(rdentry)) |
1775 | goto out_nfserr; | |
1776 | ||
2b0143b5 | 1777 | if (d_really_is_negative(rdentry)) { |
1da177e4 LT |
1778 | dput(rdentry); |
1779 | err = nfserr_noent; | |
1780 | goto out; | |
1781 | } | |
1782 | ||
1783 | if (!type) | |
2b0143b5 | 1784 | type = d_inode(rdentry)->i_mode & S_IFMT; |
1da177e4 | 1785 | |
9ce137ee | 1786 | if (type != S_IFDIR) |
b21996e3 | 1787 | host_err = vfs_unlink(dirp, rdentry, NULL); |
9ce137ee | 1788 | else |
6264d69d | 1789 | host_err = vfs_rmdir(dirp, rdentry); |
f501912a BM |
1790 | if (!host_err) |
1791 | host_err = commit_metadata(fhp); | |
541ce98c BF |
1792 | dput(rdentry); |
1793 | ||
1da177e4 | 1794 | out_nfserr: |
6264d69d | 1795 | err = nfserrno(host_err); |
f193fbab YT |
1796 | out: |
1797 | return err; | |
1da177e4 LT |
1798 | } |
1799 | ||
14f7dd63 DW |
1800 | /* |
1801 | * We do this buffering because we must not call back into the file | |
1802 | * system's ->lookup() method from the filldir callback. That may well | |
1803 | * deadlock a number of file systems. | |
1804 | * | |
1805 | * This is based heavily on the implementation of same in XFS. | |
1806 | */ | |
1807 | struct buffered_dirent { | |
1808 | u64 ino; | |
1809 | loff_t offset; | |
1810 | int namlen; | |
1811 | unsigned int d_type; | |
1812 | char name[]; | |
1813 | }; | |
1814 | ||
1815 | struct readdir_data { | |
5c0ba4e0 | 1816 | struct dir_context ctx; |
14f7dd63 DW |
1817 | char *dirent; |
1818 | size_t used; | |
53c9c5c0 | 1819 | int full; |
14f7dd63 DW |
1820 | }; |
1821 | ||
ac7576f4 MS |
1822 | static int nfsd_buffered_filldir(struct dir_context *ctx, const char *name, |
1823 | int namlen, loff_t offset, u64 ino, | |
1824 | unsigned int d_type) | |
14f7dd63 | 1825 | { |
ac7576f4 MS |
1826 | struct readdir_data *buf = |
1827 | container_of(ctx, struct readdir_data, ctx); | |
14f7dd63 DW |
1828 | struct buffered_dirent *de = (void *)(buf->dirent + buf->used); |
1829 | unsigned int reclen; | |
1830 | ||
1831 | reclen = ALIGN(sizeof(struct buffered_dirent) + namlen, sizeof(u64)); | |
53c9c5c0 AV |
1832 | if (buf->used + reclen > PAGE_SIZE) { |
1833 | buf->full = 1; | |
14f7dd63 | 1834 | return -EINVAL; |
53c9c5c0 | 1835 | } |
14f7dd63 DW |
1836 | |
1837 | de->namlen = namlen; | |
1838 | de->offset = offset; | |
1839 | de->ino = ino; | |
1840 | de->d_type = d_type; | |
1841 | memcpy(de->name, name, namlen); | |
1842 | buf->used += reclen; | |
1843 | ||
1844 | return 0; | |
1845 | } | |
1846 | ||
ac7576f4 | 1847 | static __be32 nfsd_buffered_readdir(struct file *file, nfsd_filldir_t func, |
2f9092e1 | 1848 | struct readdir_cd *cdp, loff_t *offsetp) |
2628b766 | 1849 | { |
14f7dd63 | 1850 | struct buffered_dirent *de; |
2628b766 | 1851 | int host_err; |
14f7dd63 DW |
1852 | int size; |
1853 | loff_t offset; | |
ac6614b7 AV |
1854 | struct readdir_data buf = { |
1855 | .ctx.actor = nfsd_buffered_filldir, | |
1856 | .dirent = (void *)__get_free_page(GFP_KERNEL) | |
1857 | }; | |
2628b766 | 1858 | |
14f7dd63 | 1859 | if (!buf.dirent) |
2f9092e1 | 1860 | return nfserrno(-ENOMEM); |
14f7dd63 DW |
1861 | |
1862 | offset = *offsetp; | |
2628b766 | 1863 | |
14f7dd63 DW |
1864 | while (1) { |
1865 | unsigned int reclen; | |
1866 | ||
b726e923 | 1867 | cdp->err = nfserr_eof; /* will be cleared on successful read */ |
14f7dd63 | 1868 | buf.used = 0; |
53c9c5c0 | 1869 | buf.full = 0; |
14f7dd63 | 1870 | |
5c0ba4e0 | 1871 | host_err = iterate_dir(file, &buf.ctx); |
53c9c5c0 AV |
1872 | if (buf.full) |
1873 | host_err = 0; | |
1874 | ||
1875 | if (host_err < 0) | |
14f7dd63 DW |
1876 | break; |
1877 | ||
1878 | size = buf.used; | |
1879 | ||
1880 | if (!size) | |
1881 | break; | |
1882 | ||
14f7dd63 DW |
1883 | de = (struct buffered_dirent *)buf.dirent; |
1884 | while (size > 0) { | |
1885 | offset = de->offset; | |
1886 | ||
1887 | if (func(cdp, de->name, de->namlen, de->offset, | |
1888 | de->ino, de->d_type)) | |
2f9092e1 | 1889 | break; |
14f7dd63 DW |
1890 | |
1891 | if (cdp->err != nfs_ok) | |
2f9092e1 | 1892 | break; |
14f7dd63 DW |
1893 | |
1894 | reclen = ALIGN(sizeof(*de) + de->namlen, | |
1895 | sizeof(u64)); | |
1896 | size -= reclen; | |
1897 | de = (struct buffered_dirent *)((char *)de + reclen); | |
1898 | } | |
2f9092e1 DW |
1899 | if (size > 0) /* We bailed out early */ |
1900 | break; | |
1901 | ||
c002a6c7 | 1902 | offset = vfs_llseek(file, 0, SEEK_CUR); |
14f7dd63 DW |
1903 | } |
1904 | ||
14f7dd63 | 1905 | free_page((unsigned long)(buf.dirent)); |
2628b766 DW |
1906 | |
1907 | if (host_err) | |
1908 | return nfserrno(host_err); | |
14f7dd63 DW |
1909 | |
1910 | *offsetp = offset; | |
1911 | return cdp->err; | |
2628b766 DW |
1912 | } |
1913 | ||
1da177e4 LT |
1914 | /* |
1915 | * Read entries from a directory. | |
1916 | * The NFSv3/4 verifier we ignore for now. | |
1917 | */ | |
6264d69d | 1918 | __be32 |
1da177e4 | 1919 | nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, |
ac7576f4 | 1920 | struct readdir_cd *cdp, nfsd_filldir_t func) |
1da177e4 | 1921 | { |
6264d69d | 1922 | __be32 err; |
1da177e4 LT |
1923 | struct file *file; |
1924 | loff_t offset = *offsetp; | |
06effdbb BS |
1925 | int may_flags = NFSD_MAY_READ; |
1926 | ||
1927 | /* NFSv2 only supports 32 bit cookies */ | |
1928 | if (rqstp->rq_vers > 2) | |
1929 | may_flags |= NFSD_MAY_64BIT_COOKIE; | |
1da177e4 | 1930 | |
06effdbb | 1931 | err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file); |
1da177e4 LT |
1932 | if (err) |
1933 | goto out; | |
1934 | ||
b108fe6b | 1935 | offset = vfs_llseek(file, offset, SEEK_SET); |
1da177e4 LT |
1936 | if (offset < 0) { |
1937 | err = nfserrno((int)offset); | |
1938 | goto out_close; | |
1939 | } | |
1940 | ||
14f7dd63 | 1941 | err = nfsd_buffered_readdir(file, func, cdp, offsetp); |
1da177e4 LT |
1942 | |
1943 | if (err == nfserr_eof || err == nfserr_toosmall) | |
1944 | err = nfs_ok; /* can still be found in ->err */ | |
1945 | out_close: | |
fd891454 | 1946 | fput(file); |
1da177e4 LT |
1947 | out: |
1948 | return err; | |
1949 | } | |
1950 | ||
1951 | /* | |
1952 | * Get file system stats | |
1953 | * N.B. After this call fhp needs an fh_put | |
1954 | */ | |
6264d69d | 1955 | __be32 |
04716e66 | 1956 | nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access) |
1da177e4 | 1957 | { |
ebabe9a9 CH |
1958 | __be32 err; |
1959 | ||
1960 | err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access); | |
f6360efb TI |
1961 | if (!err) { |
1962 | struct path path = { | |
1963 | .mnt = fhp->fh_export->ex_path.mnt, | |
1964 | .dentry = fhp->fh_dentry, | |
1965 | }; | |
1966 | if (vfs_statfs(&path, stat)) | |
1967 | err = nfserr_io; | |
1968 | } | |
1da177e4 LT |
1969 | return err; |
1970 | } | |
1971 | ||
c7d51402 | 1972 | static int exp_rdonly(struct svc_rqst *rqstp, struct svc_export *exp) |
e22841c6 | 1973 | { |
c7d51402 | 1974 | return nfsexp_flags(rqstp, exp) & NFSEXP_READONLY; |
e22841c6 BF |
1975 | } |
1976 | ||
1da177e4 LT |
1977 | /* |
1978 | * Check for a user's access permissions to this inode. | |
1979 | */ | |
6264d69d | 1980 | __be32 |
0ec757df BF |
1981 | nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp, |
1982 | struct dentry *dentry, int acc) | |
1da177e4 | 1983 | { |
2b0143b5 | 1984 | struct inode *inode = d_inode(dentry); |
1da177e4 LT |
1985 | int err; |
1986 | ||
aea93397 | 1987 | if ((acc & NFSD_MAY_MASK) == NFSD_MAY_NOP) |
1da177e4 LT |
1988 | return 0; |
1989 | #if 0 | |
1990 | dprintk("nfsd: permission 0x%x%s%s%s%s%s%s%s mode 0%o%s%s%s\n", | |
1991 | acc, | |
8837abca MS |
1992 | (acc & NFSD_MAY_READ)? " read" : "", |
1993 | (acc & NFSD_MAY_WRITE)? " write" : "", | |
1994 | (acc & NFSD_MAY_EXEC)? " exec" : "", | |
1995 | (acc & NFSD_MAY_SATTR)? " sattr" : "", | |
1996 | (acc & NFSD_MAY_TRUNC)? " trunc" : "", | |
1997 | (acc & NFSD_MAY_LOCK)? " lock" : "", | |
1998 | (acc & NFSD_MAY_OWNER_OVERRIDE)? " owneroverride" : "", | |
1da177e4 LT |
1999 | inode->i_mode, |
2000 | IS_IMMUTABLE(inode)? " immut" : "", | |
2001 | IS_APPEND(inode)? " append" : "", | |
2c463e95 | 2002 | __mnt_is_readonly(exp->ex_path.mnt)? " ro" : ""); |
1da177e4 | 2003 | dprintk(" owner %d/%d user %d/%d\n", |
5cc0a840 | 2004 | inode->i_uid, inode->i_gid, current_fsuid(), current_fsgid()); |
1da177e4 LT |
2005 | #endif |
2006 | ||
2007 | /* Normally we reject any write/sattr etc access on a read-only file | |
2008 | * system. But if it is IRIX doing check on write-access for a | |
2009 | * device special file, we ignore rofs. | |
2010 | */ | |
8837abca MS |
2011 | if (!(acc & NFSD_MAY_LOCAL_ACCESS)) |
2012 | if (acc & (NFSD_MAY_WRITE | NFSD_MAY_SATTR | NFSD_MAY_TRUNC)) { | |
2c463e95 DH |
2013 | if (exp_rdonly(rqstp, exp) || |
2014 | __mnt_is_readonly(exp->ex_path.mnt)) | |
1da177e4 | 2015 | return nfserr_rofs; |
8837abca | 2016 | if (/* (acc & NFSD_MAY_WRITE) && */ IS_IMMUTABLE(inode)) |
1da177e4 LT |
2017 | return nfserr_perm; |
2018 | } | |
8837abca | 2019 | if ((acc & NFSD_MAY_TRUNC) && IS_APPEND(inode)) |
1da177e4 LT |
2020 | return nfserr_perm; |
2021 | ||
8837abca | 2022 | if (acc & NFSD_MAY_LOCK) { |
1da177e4 LT |
2023 | /* If we cannot rely on authentication in NLM requests, |
2024 | * just allow locks, otherwise require read permission, or | |
2025 | * ownership | |
2026 | */ | |
2027 | if (exp->ex_flags & NFSEXP_NOAUTHNLM) | |
2028 | return 0; | |
2029 | else | |
8837abca | 2030 | acc = NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE; |
1da177e4 LT |
2031 | } |
2032 | /* | |
2033 | * The file owner always gets access permission for accesses that | |
2034 | * would normally be checked at open time. This is to make | |
2035 | * file access work even when the client has done a fchmod(fd, 0). | |
2036 | * | |
2037 | * However, `cp foo bar' should fail nevertheless when bar is | |
2038 | * readonly. A sensible way to do this might be to reject all | |
2039 | * attempts to truncate a read-only file, because a creat() call | |
2040 | * always implies file truncation. | |
2041 | * ... but this isn't really fair. A process may reasonably call | |
2042 | * ftruncate on an open file descriptor on a file with perm 000. | |
2043 | * We must trust the client to do permission checking - using "ACCESS" | |
2044 | * with NFSv3. | |
2045 | */ | |
8837abca | 2046 | if ((acc & NFSD_MAY_OWNER_OVERRIDE) && |
6fab8779 | 2047 | uid_eq(inode->i_uid, current_fsuid())) |
1da177e4 LT |
2048 | return 0; |
2049 | ||
8837abca | 2050 | /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */ |
f419a2e3 | 2051 | err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC)); |
1da177e4 LT |
2052 | |
2053 | /* Allow read access to binaries even when mode 111 */ | |
2054 | if (err == -EACCES && S_ISREG(inode->i_mode) && | |
a043226b BF |
2055 | (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) || |
2056 | acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC))) | |
f419a2e3 | 2057 | err = inode_permission(inode, MAY_EXEC); |
1da177e4 LT |
2058 | |
2059 | return err? nfserrno(err) : 0; | |
2060 | } | |
2061 | ||
2062 | void | |
2063 | nfsd_racache_shutdown(void) | |
2064 | { | |
54a66e54 JL |
2065 | struct raparms *raparm, *last_raparm; |
2066 | unsigned int i; | |
2067 | ||
1da177e4 | 2068 | dprintk("nfsd: freeing readahead buffers.\n"); |
54a66e54 JL |
2069 | |
2070 | for (i = 0; i < RAPARM_HASH_SIZE; i++) { | |
2071 | raparm = raparm_hash[i].pb_head; | |
2072 | while(raparm) { | |
2073 | last_raparm = raparm; | |
2074 | raparm = raparm->p_next; | |
2075 | kfree(last_raparm); | |
2076 | } | |
2077 | raparm_hash[i].pb_head = NULL; | |
2078 | } | |
1da177e4 LT |
2079 | } |
2080 | /* | |
2081 | * Initialize readahead param cache | |
2082 | */ | |
2083 | int | |
2084 | nfsd_racache_init(int cache_size) | |
2085 | { | |
2086 | int i; | |
fce1456a GB |
2087 | int j = 0; |
2088 | int nperbucket; | |
54a66e54 | 2089 | struct raparms **raparm = NULL; |
1da177e4 | 2090 | |
fce1456a | 2091 | |
54a66e54 | 2092 | if (raparm_hash[0].pb_head) |
1da177e4 | 2093 | return 0; |
54a66e54 | 2094 | nperbucket = DIV_ROUND_UP(cache_size, RAPARM_HASH_SIZE); |
3c7aa15d | 2095 | nperbucket = max(2, nperbucket); |
54a66e54 | 2096 | cache_size = nperbucket * RAPARM_HASH_SIZE; |
4b3bb06b YB |
2097 | |
2098 | dprintk("nfsd: allocating %d readahead buffers.\n", cache_size); | |
54a66e54 JL |
2099 | |
2100 | for (i = 0; i < RAPARM_HASH_SIZE; i++) { | |
4b3bb06b | 2101 | spin_lock_init(&raparm_hash[i].pb_lock); |
54a66e54 JL |
2102 | |
2103 | raparm = &raparm_hash[i].pb_head; | |
2104 | for (j = 0; j < nperbucket; j++) { | |
2105 | *raparm = kzalloc(sizeof(struct raparms), GFP_KERNEL); | |
2106 | if (!*raparm) | |
2107 | goto out_nomem; | |
2108 | raparm = &(*raparm)->p_next; | |
2109 | } | |
2110 | *raparm = NULL; | |
4b3bb06b YB |
2111 | } |
2112 | ||
1da177e4 LT |
2113 | nfsdstats.ra_size = cache_size; |
2114 | return 0; | |
54a66e54 JL |
2115 | |
2116 | out_nomem: | |
2117 | dprintk("nfsd: kmalloc failed, freeing readahead buffers\n"); | |
2118 | nfsd_racache_shutdown(); | |
2119 | return -ENOMEM; | |
1da177e4 | 2120 | } |