]> bbs.cooldavid.org Git - net-next-2.6.git/blame - fs/nfsd/nfs4recover.c
[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
[net-next-2.6.git] / fs / nfsd / nfs4recover.c
CommitLineData
a55370a3
N
1/*
2* linux/fs/nfsd/nfs4recover.c
3*
4* Copyright (c) 2004 The Regents of the University of Michigan.
5* All rights reserved.
6*
7* Andy Adamson <andros@citi.umich.edu>
8*
9* Redistribution and use in source and binary forms, with or without
10* modification, are permitted provided that the following conditions
11* are met:
12*
13* 1. Redistributions of source code must retain the above copyright
14* notice, this list of conditions and the following disclaimer.
15* 2. Redistributions in binary form must reproduce the above copyright
16* notice, this list of conditions and the following disclaimer in the
17* documentation and/or other materials provided with the distribution.
18* 3. Neither the name of the University nor the names of its
19* contributors may be used to endorse or promote products derived
20* from this software without specific prior written permission.
21*
22* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
23* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33*
34*/
35
36
37#include <linux/sunrpc/svc.h>
38#include <linux/nfsd/nfsd.h>
39#include <linux/nfs4.h>
40#include <linux/nfsd/state.h>
41#include <linux/nfsd/xdr4.h>
190e4fbf
N
42#include <linux/param.h>
43#include <linux/file.h>
44#include <linux/namei.h>
a55370a3
N
45#include <asm/uaccess.h>
46#include <asm/scatterlist.h>
47#include <linux/crypto.h>
48
49
50#define NFSDDBG_FACILITY NFSDDBG_PROC
51
190e4fbf 52/* Globals */
190e4fbf
N
53static struct nameidata rec_dir;
54static int rec_dir_init = 0;
55
56static void
57nfs4_save_user(uid_t *saveuid, gid_t *savegid)
58{
59 *saveuid = current->fsuid;
60 *savegid = current->fsgid;
61 current->fsuid = 0;
62 current->fsgid = 0;
63}
64
65static void
66nfs4_reset_user(uid_t saveuid, gid_t savegid)
67{
68 current->fsuid = saveuid;
69 current->fsgid = savegid;
70}
71
a55370a3
N
72static void
73md5_to_hex(char *out, char *md5)
74{
75 int i;
76
77 for (i=0; i<16; i++) {
78 unsigned char c = md5[i];
79
80 *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
81 *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
82 }
83 *out = '\0';
84}
85
86int
87nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
88{
89 struct xdr_netobj cksum;
90 struct crypto_tfm *tfm;
91 struct scatterlist sg[1];
92 int status = nfserr_resource;
93
94 dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
95 clname->len, clname->data);
eb6f1160 96 tfm = crypto_alloc_tfm("md5", CRYPTO_TFM_REQ_MAY_SLEEP);
a55370a3
N
97 if (tfm == NULL)
98 goto out;
99 cksum.len = crypto_tfm_alg_digestsize(tfm);
100 cksum.data = kmalloc(cksum.len, GFP_KERNEL);
101 if (cksum.data == NULL)
102 goto out;
103 crypto_digest_init(tfm);
104
105 sg[0].page = virt_to_page(clname->data);
106 sg[0].offset = offset_in_page(clname->data);
107 sg[0].length = clname->len;
108
109 crypto_digest_update(tfm, sg, 1);
110 crypto_digest_final(tfm, cksum.data);
111
112 md5_to_hex(dname, cksum.data);
113
114 kfree(cksum.data);
115 status = nfs_ok;
116out:
573dbd95 117 crypto_free_tfm(tfm);
a55370a3
N
118 return status;
119}
190e4fbf 120
a6ccbbb8
N
121static void
122nfsd4_sync_rec_dir(void)
c7b9a459 123{
1b1dcc1b 124 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
a6ccbbb8 125 nfsd_sync_dir(rec_dir.dentry);
1b1dcc1b 126 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459
N
127}
128
129int
130nfsd4_create_clid_dir(struct nfs4_client *clp)
131{
132 char *dname = clp->cl_recdir;
133 struct dentry *dentry;
134 uid_t uid;
135 gid_t gid;
136 int status;
137
138 dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
139
140 if (!rec_dir_init || clp->cl_firststate)
141 return 0;
142
143 nfs4_save_user(&uid, &gid);
144
145 /* lock the parent */
1b1dcc1b 146 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459
N
147
148 dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
149 if (IS_ERR(dentry)) {
150 status = PTR_ERR(dentry);
151 goto out_unlock;
152 }
153 status = -EEXIST;
154 if (dentry->d_inode) {
155 dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
156 goto out_put;
157 }
158 status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
159out_put:
160 dput(dentry);
161out_unlock:
1b1dcc1b 162 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459
N
163 if (status == 0) {
164 clp->cl_firststate = 1;
a6ccbbb8 165 nfsd4_sync_rec_dir();
c7b9a459
N
166 }
167 nfs4_reset_user(uid, gid);
168 dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
169 return status;
170}
171
190e4fbf
N
172typedef int (recdir_func)(struct dentry *, struct dentry *);
173
174struct dentry_list {
175 struct dentry *dentry;
176 struct list_head list;
177};
178
179struct dentry_list_arg {
180 struct list_head dentries;
181 struct dentry *parent;
182};
183
184static int
185nfsd4_build_dentrylist(void *arg, const char *name, int namlen,
186 loff_t offset, ino_t ino, unsigned int d_type)
187{
188 struct dentry_list_arg *dla = arg;
189 struct list_head *dentries = &dla->dentries;
190 struct dentry *parent = dla->parent;
191 struct dentry *dentry;
192 struct dentry_list *child;
193
194 if (name && isdotent(name, namlen))
195 return nfs_ok;
196 dentry = lookup_one_len(name, parent, namlen);
197 if (IS_ERR(dentry))
198 return PTR_ERR(dentry);
199 child = kmalloc(sizeof(*child), GFP_KERNEL);
200 if (child == NULL)
201 return -ENOMEM;
202 child->dentry = dentry;
203 list_add(&child->list, dentries);
204 return 0;
205}
206
207static int
208nfsd4_list_rec_dir(struct dentry *dir, recdir_func *f)
209{
210 struct file *filp;
211 struct dentry_list_arg dla = {
212 .parent = dir,
213 };
214 struct list_head *dentries = &dla.dentries;
215 struct dentry_list *child;
216 uid_t uid;
217 gid_t gid;
218 int status;
219
220 if (!rec_dir_init)
221 return 0;
222
223 nfs4_save_user(&uid, &gid);
224
225 filp = dentry_open(dget(dir), mntget(rec_dir.mnt),
226 O_RDWR);
227 status = PTR_ERR(filp);
228 if (IS_ERR(filp))
229 goto out;
230 INIT_LIST_HEAD(dentries);
231 status = vfs_readdir(filp, nfsd4_build_dentrylist, &dla);
232 fput(filp);
233 while (!list_empty(dentries)) {
234 child = list_entry(dentries->next, struct dentry_list, list);
235 status = f(dir, child->dentry);
236 if (status)
237 goto out;
238 list_del(&child->list);
239 dput(child->dentry);
240 kfree(child);
241 }
242out:
243 while (!list_empty(dentries)) {
244 child = list_entry(dentries->next, struct dentry_list, list);
245 list_del(&child->list);
246 dput(child->dentry);
247 kfree(child);
248 }
249 nfs4_reset_user(uid, gid);
250 return status;
251}
252
c7b9a459
N
253static int
254nfsd4_remove_clid_file(struct dentry *dir, struct dentry *dentry)
255{
256 int status;
257
258 if (!S_ISREG(dir->d_inode->i_mode)) {
259 printk("nfsd4: non-file found in client recovery directory\n");
260 return -EINVAL;
261 }
1b1dcc1b 262 mutex_lock(&dir->d_inode->i_mutex);
c7b9a459 263 status = vfs_unlink(dir->d_inode, dentry);
1b1dcc1b 264 mutex_unlock(&dir->d_inode->i_mutex);
c7b9a459
N
265 return status;
266}
267
268static int
269nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
270{
271 int status;
272
273 /* For now this directory should already be empty, but we empty it of
274 * any regular files anyway, just in case the directory was created by
275 * a kernel from the future.... */
276 nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file);
1b1dcc1b 277 mutex_lock(&dir->d_inode->i_mutex);
c7b9a459 278 status = vfs_rmdir(dir->d_inode, dentry);
1b1dcc1b 279 mutex_unlock(&dir->d_inode->i_mutex);
c7b9a459
N
280 return status;
281}
282
283static int
284nfsd4_unlink_clid_dir(char *name, int namlen)
285{
286 struct dentry *dentry;
287 int status;
288
289 dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
290
1b1dcc1b 291 mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 292 dentry = lookup_one_len(name, rec_dir.dentry, namlen);
1b1dcc1b 293 mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459
N
294 if (IS_ERR(dentry)) {
295 status = PTR_ERR(dentry);
296 return status;
297 }
298 status = -ENOENT;
299 if (!dentry->d_inode)
300 goto out;
301
302 status = nfsd4_clear_clid_dir(rec_dir.dentry, dentry);
303out:
304 dput(dentry);
305 return status;
306}
307
308void
309nfsd4_remove_clid_dir(struct nfs4_client *clp)
310{
311 uid_t uid;
312 gid_t gid;
313 int status;
314
315 if (!rec_dir_init || !clp->cl_firststate)
316 return;
317
67be4313 318 clp->cl_firststate = 0;
c7b9a459
N
319 nfs4_save_user(&uid, &gid);
320 status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
321 nfs4_reset_user(uid, gid);
322 if (status == 0)
a6ccbbb8 323 nfsd4_sync_rec_dir();
c7b9a459
N
324 if (status)
325 printk("NFSD: Failed to remove expired client state directory"
326 " %.*s\n", HEXDIR_LEN, clp->cl_recdir);
327 return;
328}
329
330static int
331purge_old(struct dentry *parent, struct dentry *child)
332{
333 int status;
334
335 if (nfs4_has_reclaimed_state(child->d_name.name))
336 return nfs_ok;
337
338 status = nfsd4_clear_clid_dir(parent, child);
339 if (status)
340 printk("failed to remove client recovery directory %s\n",
341 child->d_name.name);
342 /* Keep trying, success or failure: */
343 return nfs_ok;
344}
345
346void
347nfsd4_recdir_purge_old(void) {
348 int status;
349
350 if (!rec_dir_init)
351 return;
352 status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
353 if (status == 0)
a6ccbbb8 354 nfsd4_sync_rec_dir();
c7b9a459
N
355 if (status)
356 printk("nfsd4: failed to purge old clients from recovery"
357 " directory %s\n", rec_dir.dentry->d_name.name);
358 return;
359}
360
190e4fbf
N
361static int
362load_recdir(struct dentry *parent, struct dentry *child)
363{
364 if (child->d_name.len != HEXDIR_LEN - 1) {
365 printk("nfsd4: illegal name %s in recovery directory\n",
366 child->d_name.name);
367 /* Keep trying; maybe the others are OK: */
368 return nfs_ok;
369 }
370 nfs4_client_to_reclaim(child->d_name.name);
371 return nfs_ok;
372}
373
374int
375nfsd4_recdir_load(void) {
376 int status;
377
378 status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
379 if (status)
380 printk("nfsd4: failed loading clients from recovery"
381 " directory %s\n", rec_dir.dentry->d_name.name);
382 return status;
383}
384
385/*
386 * Hold reference to the recovery directory.
387 */
388
389void
390nfsd4_init_recdir(char *rec_dirname)
391{
392 uid_t uid = 0;
393 gid_t gid = 0;
394 int status;
395
396 printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
397 rec_dirname);
398
399 BUG_ON(rec_dir_init);
400
401 nfs4_save_user(&uid, &gid);
402
403 status = path_lookup(rec_dirname, LOOKUP_FOLLOW, &rec_dir);
404 if (status == -ENOENT)
405 printk("NFSD: recovery directory %s doesn't exist\n",
406 rec_dirname);
407
408 if (!status)
409 rec_dir_init = 1;
410 nfs4_reset_user(uid, gid);
411}
412
413void
414nfsd4_shutdown_recdir(void)
415{
416 if (!rec_dir_init)
417 return;
418 rec_dir_init = 0;
419 path_release(&rec_dir);
420}