2b696ae6655a10306f5111c90f14a5af645c9220
[linux-2.6.git] / fs / 9p / vfs_inode.c
1 /*
2  *  linux/fs/9p/vfs_inode.c
3  *
4  * This file contains vfs inode ops for the 9P2000 protocol.
5  *
6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or
12  *  (at your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful,
15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *  GNU General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License
20  *  along with this program; if not, write to:
21  *  Free Software Foundation
22  *  51 Franklin Street, Fifth Floor
23  *  Boston, MA  02111-1301  USA
24  *
25  */
26
27 #include <linux/module.h>
28 #include <linux/errno.h>
29 #include <linux/fs.h>
30 #include <linux/file.h>
31 #include <linux/pagemap.h>
32 #include <linux/stat.h>
33 #include <linux/string.h>
34 #include <linux/smp_lock.h>
35 #include <linux/inet.h>
36 #include <linux/namei.h>
37 #include <linux/idr.h>
38
39 #include "debug.h"
40 #include "v9fs.h"
41 #include "9p.h"
42 #include "v9fs_vfs.h"
43 #include "conv.h"
44 #include "fid.h"
45
46 static struct inode_operations v9fs_dir_inode_operations;
47 static struct inode_operations v9fs_dir_inode_operations_ext;
48 static struct inode_operations v9fs_file_inode_operations;
49 static struct inode_operations v9fs_symlink_inode_operations;
50
51 /**
52  * unixmode2p9mode - convert unix mode bits to plan 9
53  * @v9ses: v9fs session information
54  * @mode: mode to convert
55  *
56  */
57
58 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
59 {
60         int res;
61         res = mode & 0777;
62         if (S_ISDIR(mode))
63                 res |= V9FS_DMDIR;
64         if (v9ses->extended) {
65                 if (S_ISLNK(mode))
66                         res |= V9FS_DMSYMLINK;
67                 if (v9ses->nodev == 0) {
68                         if (S_ISSOCK(mode))
69                                 res |= V9FS_DMSOCKET;
70                         if (S_ISFIFO(mode))
71                                 res |= V9FS_DMNAMEDPIPE;
72                         if (S_ISBLK(mode))
73                                 res |= V9FS_DMDEVICE;
74                         if (S_ISCHR(mode))
75                                 res |= V9FS_DMDEVICE;
76                 }
77
78                 if ((mode & S_ISUID) == S_ISUID)
79                         res |= V9FS_DMSETUID;
80                 if ((mode & S_ISGID) == S_ISGID)
81                         res |= V9FS_DMSETGID;
82                 if ((mode & V9FS_DMLINK))
83                         res |= V9FS_DMLINK;
84         }
85
86         return res;
87 }
88
89 /**
90  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
91  * @v9ses: v9fs session information
92  * @mode: mode to convert
93  *
94  */
95
96 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
97 {
98         int res;
99
100         res = mode & 0777;
101
102         if ((mode & V9FS_DMDIR) == V9FS_DMDIR)
103                 res |= S_IFDIR;
104         else if ((mode & V9FS_DMSYMLINK) && (v9ses->extended))
105                 res |= S_IFLNK;
106         else if ((mode & V9FS_DMSOCKET) && (v9ses->extended)
107                  && (v9ses->nodev == 0))
108                 res |= S_IFSOCK;
109         else if ((mode & V9FS_DMNAMEDPIPE) && (v9ses->extended)
110                  && (v9ses->nodev == 0))
111                 res |= S_IFIFO;
112         else if ((mode & V9FS_DMDEVICE) && (v9ses->extended)
113                  && (v9ses->nodev == 0))
114                 res |= S_IFBLK;
115         else
116                 res |= S_IFREG;
117
118         if (v9ses->extended) {
119                 if ((mode & V9FS_DMSETUID) == V9FS_DMSETUID)
120                         res |= S_ISUID;
121
122                 if ((mode & V9FS_DMSETGID) == V9FS_DMSETGID)
123                         res |= S_ISGID;
124         }
125
126         return res;
127 }
128
129 /**
130  * v9fs_blank_mistat - helper function to setup a 9P stat structure
131  * @v9ses: 9P session info (for determining extended mode)
132  * @mistat: structure to initialize
133  *
134  */
135
136 static void
137 v9fs_blank_mistat(struct v9fs_session_info *v9ses, struct v9fs_stat *mistat)
138 {
139         mistat->type = ~0;
140         mistat->dev = ~0;
141         mistat->qid.type = ~0;
142         mistat->qid.version = ~0;
143         *((long long *)&mistat->qid.path) = ~0;
144         mistat->mode = ~0;
145         mistat->atime = ~0;
146         mistat->mtime = ~0;
147         mistat->length = ~0;
148         mistat->name = mistat->data;
149         mistat->uid = mistat->data;
150         mistat->gid = mistat->data;
151         mistat->muid = mistat->data;
152         if (v9ses->extended) {
153                 mistat->n_uid = ~0;
154                 mistat->n_gid = ~0;
155                 mistat->n_muid = ~0;
156                 mistat->extension = mistat->data;
157         }
158         *mistat->data = 0;
159 }
160
161 /**
162  * v9fs_mistat2unix - convert mistat to unix stat
163  * @mistat: Plan 9 metadata (mistat) structure
164  * @buf: unix metadata (stat) structure to populate
165  * @sb: superblock
166  *
167  */
168
169 static void
170 v9fs_mistat2unix(struct v9fs_stat *mistat, struct stat *buf,
171                  struct super_block *sb)
172 {
173         struct v9fs_session_info *v9ses = sb ? sb->s_fs_info : NULL;
174
175         buf->st_nlink = 1;
176
177         buf->st_atime = mistat->atime;
178         buf->st_mtime = mistat->mtime;
179         buf->st_ctime = mistat->mtime;
180
181         buf->st_uid = (unsigned short)-1;
182         buf->st_gid = (unsigned short)-1;
183
184         if (v9ses && v9ses->extended) {
185                 /* TODO: string to uid mapping via user-space daemon */
186                 if (mistat->n_uid != -1)
187                         sscanf(mistat->uid, "%x", (unsigned int *)&buf->st_uid);
188
189                 if (mistat->n_gid != -1)
190                         sscanf(mistat->gid, "%x", (unsigned int *)&buf->st_gid);
191         }
192
193         if (buf->st_uid == (unsigned short)-1)
194                 buf->st_uid = v9ses->uid;
195         if (buf->st_gid == (unsigned short)-1)
196                 buf->st_gid = v9ses->gid;
197
198         buf->st_mode = p9mode2unixmode(v9ses, mistat->mode);
199         if ((S_ISBLK(buf->st_mode)) || (S_ISCHR(buf->st_mode))) {
200                 char type = 0;
201                 int major = -1;
202                 int minor = -1;
203                 sscanf(mistat->extension, "%c %u %u", &type, &major, &minor);
204                 switch (type) {
205                 case 'c':
206                         buf->st_mode &= ~S_IFBLK;
207                         buf->st_mode |= S_IFCHR;
208                         break;
209                 case 'b':
210                         break;
211                 default:
212                         dprintk(DEBUG_ERROR, "Unknown special type %c (%s)\n",
213                                 type, mistat->extension);
214                 };
215                 buf->st_rdev = MKDEV(major, minor);
216         } else
217                 buf->st_rdev = 0;
218
219         buf->st_size = mistat->length;
220
221         buf->st_blksize = sb->s_blocksize;
222         buf->st_blocks =
223             (buf->st_size + buf->st_blksize - 1) >> sb->s_blocksize_bits;
224 }
225
226 /**
227  * v9fs_get_inode - helper function to setup an inode
228  * @sb: superblock
229  * @mode: mode to setup inode with
230  *
231  */
232
233 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
234 {
235         struct inode *inode = NULL;
236         struct v9fs_session_info *v9ses = sb->s_fs_info;
237
238         dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
239
240         inode = new_inode(sb);
241         if (inode) {
242                 inode->i_mode = mode;
243                 inode->i_uid = current->fsuid;
244                 inode->i_gid = current->fsgid;
245                 inode->i_blksize = sb->s_blocksize;
246                 inode->i_blocks = 0;
247                 inode->i_rdev = 0;
248                 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
249
250                 switch (mode & S_IFMT) {
251                 case S_IFIFO:
252                 case S_IFBLK:
253                 case S_IFCHR:
254                 case S_IFSOCK:
255                         if(!v9ses->extended) {
256                                 dprintk(DEBUG_ERROR, "special files without extended mode\n");
257                                 return ERR_PTR(-EINVAL);
258                         }
259                         init_special_inode(inode, inode->i_mode,
260                                            inode->i_rdev);
261                         break;
262                 case S_IFREG:
263                         inode->i_op = &v9fs_file_inode_operations;
264                         inode->i_fop = &v9fs_file_operations;
265                         break;
266                 case S_IFLNK:
267                         if(!v9ses->extended) {
268                                 dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n");
269                                 return ERR_PTR(-EINVAL);
270                         }
271                         inode->i_op = &v9fs_symlink_inode_operations;
272                         break;
273                 case S_IFDIR:
274                         inode->i_nlink++;
275                         if(v9ses->extended)
276                                 inode->i_op = &v9fs_dir_inode_operations_ext;
277                         else
278                                 inode->i_op = &v9fs_dir_inode_operations;
279                         inode->i_fop = &v9fs_dir_operations;
280                         break;
281                 default:
282                         dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
283                                 mode, mode & S_IFMT);
284                         return ERR_PTR(-EINVAL);
285                 }
286         } else {
287                 eprintk(KERN_WARNING, "Problem allocating inode\n");
288                 return ERR_PTR(-ENOMEM);
289         }
290         return inode;
291 }
292
293 /**
294  * v9fs_create - helper function to create files and directories
295  * @dir: directory inode file is being created in
296  * @file_dentry: dentry file is being created in
297  * @perm: permissions file is being created with
298  * @open_mode: resulting open mode for file
299  *
300  */
301
302 static int
303 v9fs_create(struct inode *dir,
304             struct dentry *file_dentry,
305             unsigned int perm, unsigned int open_mode)
306 {
307         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
308         struct super_block *sb = dir->i_sb;
309         struct v9fs_fid *dirfid =
310             v9fs_fid_lookup(file_dentry->d_parent);
311         struct v9fs_fid *fid = NULL;
312         struct inode *file_inode = NULL;
313         struct v9fs_fcall *fcall = NULL;
314         struct v9fs_qid qid;
315         struct stat newstat;
316         int dirfidnum = -1;
317         long newfid = -1;
318         int result = 0;
319         unsigned int iounit = 0;
320         int wfidno = -1;
321
322         perm = unixmode2p9mode(v9ses, perm);
323
324         dprintk(DEBUG_VFS, "dir: %p dentry: %p perm: %o mode: %o\n", dir,
325                 file_dentry, perm, open_mode);
326
327         if (!dirfid)
328                 return -EBADF;
329
330         dirfidnum = dirfid->fid;
331         if (dirfidnum < 0) {
332                 dprintk(DEBUG_ERROR, "No fid for the directory #%lu\n",
333                         dir->i_ino);
334                 return -EBADF;
335         }
336
337         if (file_dentry->d_inode) {
338                 dprintk(DEBUG_ERROR,
339                         "Odd. There is an inode for dir %lu, name :%s:\n",
340                         dir->i_ino, file_dentry->d_name.name);
341                 return -EEXIST;
342         }
343
344         newfid = v9fs_get_idpool(&v9ses->fidpool);
345         if (newfid < 0) {
346                 eprintk(KERN_WARNING, "no free fids available\n");
347                 return -ENOSPC;
348         }
349
350         result = v9fs_t_walk(v9ses, dirfidnum, newfid, NULL, &fcall);
351         if (result < 0) {
352                 dprintk(DEBUG_ERROR, "clone error: %s\n", FCALL_ERROR(fcall));
353                 v9fs_put_idpool(newfid, &v9ses->fidpool);
354                 newfid = -1;
355                 goto CleanUpFid;
356         }
357
358         kfree(fcall);
359
360         result = v9fs_t_create(v9ses, newfid, (char *)file_dentry->d_name.name,
361                                perm, open_mode, &fcall);
362         if (result < 0) {
363                 dprintk(DEBUG_ERROR, "create fails: %s(%d)\n",
364                         FCALL_ERROR(fcall), result);
365
366                 goto CleanUpFid;
367         }
368
369         iounit = fcall->params.rcreate.iounit;
370         qid = fcall->params.rcreate.qid;
371         kfree(fcall);
372
373         fid = v9fs_fid_create(file_dentry, v9ses, newfid, 1);
374         dprintk(DEBUG_VFS, "fid %p %d\n", fid, fid->fidcreate);
375         if (!fid) {
376                 result = -ENOMEM;
377                 goto CleanUpFid;
378         }
379
380         fid->qid = qid;
381         fid->iounit = iounit;
382
383         /* walk to the newly created file and put the fid in the dentry */
384         wfidno = v9fs_get_idpool(&v9ses->fidpool);
385         if (newfid < 0) {
386                 eprintk(KERN_WARNING, "no free fids available\n");
387                 return -ENOSPC;
388         }
389
390         result = v9fs_t_walk(v9ses, dirfidnum, wfidno,
391                 (char *) file_dentry->d_name.name, NULL);
392         if (result < 0) {
393                 dprintk(DEBUG_ERROR, "clone error: %s\n", FCALL_ERROR(fcall));
394                 v9fs_put_idpool(wfidno, &v9ses->fidpool);
395                 wfidno = -1;
396                 goto CleanUpFid;
397         }
398
399         if (!v9fs_fid_create(file_dentry, v9ses, wfidno, 0)) {
400                 if (!v9fs_t_clunk(v9ses, newfid, &fcall)) {
401                         v9fs_put_idpool(wfidno, &v9ses->fidpool);
402                 }
403
404                 goto CleanUpFid;
405         }
406
407         if ((perm & V9FS_DMSYMLINK) || (perm & V9FS_DMLINK) ||
408             (perm & V9FS_DMNAMEDPIPE) || (perm & V9FS_DMSOCKET) ||
409             (perm & V9FS_DMDEVICE))
410                 return 0;
411
412         result = v9fs_t_stat(v9ses, newfid, &fcall);
413         if (result < 0) {
414                 dprintk(DEBUG_ERROR, "stat error: %s(%d)\n", FCALL_ERROR(fcall),
415                         result);
416                 goto CleanUpFid;
417         }
418
419         v9fs_mistat2unix(fcall->params.rstat.stat, &newstat, sb);
420
421         file_inode = v9fs_get_inode(sb, newstat.st_mode);
422         if ((!file_inode) || IS_ERR(file_inode)) {
423                 dprintk(DEBUG_ERROR, "create inode failed\n");
424                 result = -EBADF;
425                 goto CleanUpFid;
426         }
427
428         v9fs_mistat2inode(fcall->params.rstat.stat, file_inode, sb);
429         kfree(fcall);
430         d_instantiate(file_dentry, file_inode);
431
432         if (perm & V9FS_DMDIR) {
433                 if (!v9fs_t_clunk(v9ses, newfid, &fcall))
434                         v9fs_put_idpool(newfid, &v9ses->fidpool);
435                 else
436                         dprintk(DEBUG_ERROR, "clunk for mkdir failed: %s\n",
437                                 FCALL_ERROR(fcall));
438                 kfree(fcall);
439                 fid->fidopen = 0;
440                 fid->fidcreate = 0;
441                 d_drop(file_dentry);
442         }
443
444         return 0;
445
446       CleanUpFid:
447         kfree(fcall);
448
449         if (newfid >= 0) {
450                 if (!v9fs_t_clunk(v9ses, newfid, &fcall))
451                         v9fs_put_idpool(newfid, &v9ses->fidpool);
452                 else
453                         dprintk(DEBUG_ERROR, "clunk failed: %s\n",
454                                 FCALL_ERROR(fcall));
455
456                 kfree(fcall);
457         }
458         if (wfidno >= 0) {
459                 if (!v9fs_t_clunk(v9ses, wfidno, &fcall))
460                         v9fs_put_idpool(wfidno, &v9ses->fidpool);
461                 else
462                         dprintk(DEBUG_ERROR, "clunk failed: %s\n",
463                                 FCALL_ERROR(fcall));
464
465                 kfree(fcall);
466         }
467         return result;
468 }
469
470 /**
471  * v9fs_remove - helper function to remove files and directories
472  * @dir: directory inode that is being deleted
473  * @file:  dentry that is being deleted
474  * @rmdir: removing a directory
475  *
476  */
477
478 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
479 {
480         struct v9fs_fcall *fcall = NULL;
481         struct super_block *sb = NULL;
482         struct v9fs_session_info *v9ses = NULL;
483         struct v9fs_fid *v9fid = NULL;
484         struct inode *file_inode = NULL;
485         int fid = -1;
486         int result = 0;
487
488         dprintk(DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
489                 rmdir);
490
491         file_inode = file->d_inode;
492         sb = file_inode->i_sb;
493         v9ses = v9fs_inode2v9ses(file_inode);
494         v9fid = v9fs_fid_lookup(file);
495
496         if (!v9fid) {
497                 dprintk(DEBUG_ERROR,
498                         "no v9fs_fid\n");
499                 return -EBADF;
500         }
501
502         fid = v9fid->fid;
503         if (fid < 0) {
504                 dprintk(DEBUG_ERROR, "inode #%lu, no fid!\n",
505                         file_inode->i_ino);
506                 return -EBADF;
507         }
508
509         result = v9fs_t_remove(v9ses, fid, &fcall);
510         if (result < 0)
511                 dprintk(DEBUG_ERROR, "remove of file fails: %s(%d)\n",
512                         FCALL_ERROR(fcall), result);
513         else {
514                 v9fs_put_idpool(fid, &v9ses->fidpool);
515                 v9fs_fid_destroy(v9fid);
516         }
517
518         kfree(fcall);
519         return result;
520 }
521
522 /**
523  * v9fs_vfs_create - VFS hook to create files
524  * @inode: directory inode that is being deleted
525  * @dentry:  dentry that is being deleted
526  * @perm: create permissions
527  * @nd: path information
528  *
529  */
530
531 static int
532 v9fs_vfs_create(struct inode *inode, struct dentry *dentry, int perm,
533                 struct nameidata *nd)
534 {
535         return v9fs_create(inode, dentry, perm, O_RDWR);
536 }
537
538 /**
539  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
540  * @inode:  inode that is being unlinked
541  * @dentry: dentry that is being unlinked
542  * @mode: mode for new directory
543  *
544  */
545
546 static int v9fs_vfs_mkdir(struct inode *inode, struct dentry *dentry, int mode)
547 {
548         return v9fs_create(inode, dentry, mode | S_IFDIR, O_RDONLY);
549 }
550
551 /**
552  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
553  * @dir:  inode that is being walked from
554  * @dentry: dentry that is being walked to?
555  * @nameidata: path data
556  *
557  */
558
559 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
560                                       struct nameidata *nameidata)
561 {
562         struct super_block *sb;
563         struct v9fs_session_info *v9ses;
564         struct v9fs_fid *dirfid;
565         struct v9fs_fid *fid;
566         struct inode *inode;
567         struct v9fs_fcall *fcall = NULL;
568         struct stat newstat;
569         int dirfidnum = -1;
570         int newfid = -1;
571         int result = 0;
572
573         dprintk(DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
574                 dir, dentry->d_iname, dentry, nameidata);
575
576         sb = dir->i_sb;
577         v9ses = v9fs_inode2v9ses(dir);
578         dirfid = v9fs_fid_lookup(dentry->d_parent);
579
580         if (!dirfid) {
581                 dprintk(DEBUG_ERROR, "no dirfid\n");
582                 return ERR_PTR(-EINVAL);
583         }
584
585         dirfidnum = dirfid->fid;
586
587         if (dirfidnum < 0) {
588                 dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n",
589                         dir, dir->i_ino);
590                 return ERR_PTR(-EBADF);
591         }
592
593         newfid = v9fs_get_idpool(&v9ses->fidpool);
594         if (newfid < 0) {
595                 eprintk(KERN_WARNING, "newfid fails!\n");
596                 return ERR_PTR(-ENOSPC);
597         }
598
599         result =
600             v9fs_t_walk(v9ses, dirfidnum, newfid, (char *)dentry->d_name.name,
601                         NULL);
602         if (result < 0) {
603                 v9fs_put_idpool(newfid, &v9ses->fidpool);
604                 if (result == -ENOENT) {
605                         d_add(dentry, NULL);
606                         dprintk(DEBUG_VFS,
607                                 "Return negative dentry %p count %d\n",
608                                 dentry, atomic_read(&dentry->d_count));
609                         return NULL;
610                 }
611                 dprintk(DEBUG_ERROR, "walk error:%d\n", result);
612                 goto FreeFcall;
613         }
614
615         result = v9fs_t_stat(v9ses, newfid, &fcall);
616         if (result < 0) {
617                 dprintk(DEBUG_ERROR, "stat error\n");
618                 goto FreeFcall;
619         }
620
621         v9fs_mistat2unix(fcall->params.rstat.stat, &newstat, sb);
622         inode = v9fs_get_inode(sb, newstat.st_mode);
623
624         if (IS_ERR(inode) && (PTR_ERR(inode) == -ENOSPC)) {
625                 eprintk(KERN_WARNING, "inode alloc failes, returns %ld\n",
626                         PTR_ERR(inode));
627
628                 result = -ENOSPC;
629                 goto FreeFcall;
630         }
631
632         inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat->qid);
633
634         fid = v9fs_fid_create(dentry, v9ses, newfid, 0);
635         if (fid == NULL) {
636                 dprintk(DEBUG_ERROR, "couldn't insert\n");
637                 result = -ENOMEM;
638                 goto FreeFcall;
639         }
640
641         fid->qid = fcall->params.rstat.stat->qid;
642
643         dentry->d_op = &v9fs_dentry_operations;
644         v9fs_mistat2inode(fcall->params.rstat.stat, inode, inode->i_sb);
645
646         d_add(dentry, inode);
647         kfree(fcall);
648
649         return NULL;
650
651       FreeFcall:
652         kfree(fcall);
653         return ERR_PTR(result);
654 }
655
656 /**
657  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
658  * @i:  inode that is being unlinked
659  * @d: dentry that is being unlinked
660  *
661  */
662
663 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
664 {
665         return v9fs_remove(i, d, 0);
666 }
667
668 /**
669  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
670  * @i:  inode that is being unlinked
671  * @d: dentry that is being unlinked
672  *
673  */
674
675 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
676 {
677         return v9fs_remove(i, d, 1);
678 }
679
680 /**
681  * v9fs_vfs_rename - VFS hook to rename an inode
682  * @old_dir:  old dir inode
683  * @old_dentry: old dentry
684  * @new_dir: new dir inode
685  * @new_dentry: new dentry
686  *
687  */
688
689 static int
690 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
691                 struct inode *new_dir, struct dentry *new_dentry)
692 {
693         struct inode *old_inode = old_dentry->d_inode;
694         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode);
695         struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry);
696         struct v9fs_fid *olddirfid =
697             v9fs_fid_lookup(old_dentry->d_parent);
698         struct v9fs_fid *newdirfid =
699             v9fs_fid_lookup(new_dentry->d_parent);
700         struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
701         struct v9fs_fcall *fcall = NULL;
702         int fid = -1;
703         int olddirfidnum = -1;
704         int newdirfidnum = -1;
705         int retval = 0;
706
707         dprintk(DEBUG_VFS, "\n");
708
709         if (!mistat)
710                 return -ENOMEM;
711
712         if ((!oldfid) || (!olddirfid) || (!newdirfid)) {
713                 dprintk(DEBUG_ERROR, "problem with arguments\n");
714                 return -EBADF;
715         }
716
717         /* 9P can only handle file rename in the same directory */
718         if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
719                 dprintk(DEBUG_ERROR, "old dir and new dir are different\n");
720                 retval = -EPERM;
721                 goto FreeFcallnBail;
722         }
723
724         fid = oldfid->fid;
725         olddirfidnum = olddirfid->fid;
726         newdirfidnum = newdirfid->fid;
727
728         if (fid < 0) {
729                 dprintk(DEBUG_ERROR, "no fid for old file #%lu\n",
730                         old_inode->i_ino);
731                 retval = -EBADF;
732                 goto FreeFcallnBail;
733         }
734
735         v9fs_blank_mistat(v9ses, mistat);
736
737         strcpy(mistat->data + 1, v9ses->name);
738         mistat->name = mistat->data + 1 + strlen(v9ses->name);
739
740         if (new_dentry->d_name.len >
741             (v9ses->maxdata - strlen(v9ses->name) - sizeof(struct v9fs_stat))) {
742                 dprintk(DEBUG_ERROR, "new name too long\n");
743                 goto FreeFcallnBail;
744         }
745
746         strcpy(mistat->name, new_dentry->d_name.name);
747         retval = v9fs_t_wstat(v9ses, fid, mistat, &fcall);
748
749       FreeFcallnBail:
750         kfree(mistat);
751
752         if (retval < 0)
753                 dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
754                         FCALL_ERROR(fcall));
755
756         kfree(fcall);
757         return retval;
758 }
759
760 /**
761  * v9fs_vfs_getattr - retreive file metadata
762  * @mnt - mount information
763  * @dentry - file to get attributes on
764  * @stat - metadata structure to populate
765  *
766  */
767
768 static int
769 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
770                  struct kstat *stat)
771 {
772         struct v9fs_fcall *fcall = NULL;
773         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
774         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
775         int err = -EPERM;
776
777         dprintk(DEBUG_VFS, "dentry: %p\n", dentry);
778         if (!fid) {
779                 dprintk(DEBUG_ERROR,
780                         "couldn't find fid associated with dentry\n");
781                 return -EBADF;
782         }
783
784         err = v9fs_t_stat(v9ses, fid->fid, &fcall);
785
786         if (err < 0)
787                 dprintk(DEBUG_ERROR, "stat error\n");
788         else {
789                 v9fs_mistat2inode(fcall->params.rstat.stat, dentry->d_inode,
790                                   dentry->d_inode->i_sb);
791                 generic_fillattr(dentry->d_inode, stat);
792         }
793
794         kfree(fcall);
795         return err;
796 }
797
798 /**
799  * v9fs_vfs_setattr - set file metadata
800  * @dentry: file whose metadata to set
801  * @iattr: metadata assignment structure
802  *
803  */
804
805 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
806 {
807         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
808         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
809         struct v9fs_fcall *fcall = NULL;
810         struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
811         int res = -EPERM;
812
813         dprintk(DEBUG_VFS, "\n");
814
815         if (!mistat)
816                 return -ENOMEM;
817
818         if (!fid) {
819                 dprintk(DEBUG_ERROR,
820                         "Couldn't find fid associated with dentry\n");
821                 return -EBADF;
822         }
823
824         v9fs_blank_mistat(v9ses, mistat);
825         if (iattr->ia_valid & ATTR_MODE)
826                 mistat->mode = unixmode2p9mode(v9ses, iattr->ia_mode);
827
828         if (iattr->ia_valid & ATTR_MTIME)
829                 mistat->mtime = iattr->ia_mtime.tv_sec;
830
831         if (iattr->ia_valid & ATTR_ATIME)
832                 mistat->atime = iattr->ia_atime.tv_sec;
833
834         if (iattr->ia_valid & ATTR_SIZE)
835                 mistat->length = iattr->ia_size;
836
837         if (v9ses->extended) {
838                 char *ptr = mistat->data+1;
839
840                 if (iattr->ia_valid & ATTR_UID) {
841                         mistat->uid = ptr;
842                         ptr += 1+sprintf(ptr, "%08x", iattr->ia_uid);
843                         mistat->n_uid = iattr->ia_uid;
844                 }
845
846                 if (iattr->ia_valid & ATTR_GID) {
847                         mistat->gid = ptr;
848                         ptr += 1+sprintf(ptr, "%08x", iattr->ia_gid);
849                         mistat->n_gid = iattr->ia_gid;
850                 }
851         }
852
853         res = v9fs_t_wstat(v9ses, fid->fid, mistat, &fcall);
854
855         if (res < 0)
856                 dprintk(DEBUG_ERROR, "wstat error: %s\n", FCALL_ERROR(fcall));
857
858         kfree(mistat);
859         kfree(fcall);
860
861         if (res >= 0)
862                 res = inode_setattr(dentry->d_inode, iattr);
863
864         return res;
865 }
866
867 /**
868  * v9fs_mistat2inode - populate an inode structure with mistat info
869  * @mistat: Plan 9 metadata (mistat) structure
870  * @inode: inode to populate
871  * @sb: superblock of filesystem
872  *
873  */
874
875 void
876 v9fs_mistat2inode(struct v9fs_stat *mistat, struct inode *inode,
877                   struct super_block *sb)
878 {
879         struct v9fs_session_info *v9ses = sb->s_fs_info;
880
881         inode->i_nlink = 1;
882
883         inode->i_atime.tv_sec = mistat->atime;
884         inode->i_mtime.tv_sec = mistat->mtime;
885         inode->i_ctime.tv_sec = mistat->mtime;
886
887         inode->i_uid = -1;
888         inode->i_gid = -1;
889
890         if (v9ses->extended) {
891                 /* TODO: string to uid mapping via user-space daemon */
892                 inode->i_uid = mistat->n_uid;
893                 inode->i_gid = mistat->n_gid;
894
895                 if (mistat->n_uid == -1)
896                         sscanf(mistat->uid, "%x", &inode->i_uid);
897
898                 if (mistat->n_gid == -1)
899                         sscanf(mistat->gid, "%x", &inode->i_gid);
900         }
901
902         if (inode->i_uid == -1)
903                 inode->i_uid = v9ses->uid;
904         if (inode->i_gid == -1)
905                 inode->i_gid = v9ses->gid;
906
907         inode->i_mode = p9mode2unixmode(v9ses, mistat->mode);
908         if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
909                 char type = 0;
910                 int major = -1;
911                 int minor = -1;
912                 sscanf(mistat->extension, "%c %u %u", &type, &major, &minor);
913                 switch (type) {
914                 case 'c':
915                         inode->i_mode &= ~S_IFBLK;
916                         inode->i_mode |= S_IFCHR;
917                         break;
918                 case 'b':
919                         break;
920                 default:
921                         dprintk(DEBUG_ERROR, "Unknown special type %c (%s)\n",
922                                 type, mistat->extension);
923                 };
924                 inode->i_rdev = MKDEV(major, minor);
925         } else
926                 inode->i_rdev = 0;
927
928         inode->i_size = mistat->length;
929
930         inode->i_blksize = sb->s_blocksize;
931         inode->i_blocks =
932             (inode->i_size + inode->i_blksize - 1) >> sb->s_blocksize_bits;
933 }
934
935 /**
936  * v9fs_qid2ino - convert qid into inode number
937  * @qid: qid to hash
938  *
939  * BUG: potential for inode number collisions?
940  */
941
942 ino_t v9fs_qid2ino(struct v9fs_qid *qid)
943 {
944         u64 path = qid->path + 2;
945         ino_t i = 0;
946
947         if (sizeof(ino_t) == sizeof(path))
948                 memcpy(&i, &path, sizeof(ino_t));
949         else
950                 i = (ino_t) (path ^ (path >> 32));
951
952         return i;
953 }
954
955 /**
956  * v9fs_vfs_symlink - helper function to create symlinks
957  * @dir: directory inode containing symlink
958  * @dentry: dentry for symlink
959  * @symname: symlink data
960  *
961  * See 9P2000.u RFC for more information
962  *
963  */
964
965 static int
966 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
967 {
968         int retval = -EPERM;
969         struct v9fs_fid *newfid;
970         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
971         struct v9fs_fcall *fcall = NULL;
972         struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
973
974         dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
975                 symname);
976
977         if (!mistat)
978                 return -ENOMEM;
979
980         if (!v9ses->extended) {
981                 dprintk(DEBUG_ERROR, "not extended\n");
982                 goto FreeFcall;
983         }
984
985         /* issue a create */
986         retval = v9fs_create(dir, dentry, S_IFLNK, 0);
987         if (retval != 0)
988                 goto FreeFcall;
989
990         newfid = v9fs_fid_lookup(dentry);
991
992         /* issue a twstat */
993         v9fs_blank_mistat(v9ses, mistat);
994         strcpy(mistat->data + 1, symname);
995         mistat->extension = mistat->data + 1;
996         retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
997         if (retval < 0) {
998                 dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
999                         FCALL_ERROR(fcall));
1000                 goto FreeFcall;
1001         }
1002
1003         kfree(fcall);
1004
1005         if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
1006                 dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
1007                         FCALL_ERROR(fcall));
1008                 goto FreeFcall;
1009         }
1010
1011         d_drop(dentry);         /* FID - will this also clunk? */
1012
1013       FreeFcall:
1014         kfree(mistat);
1015         kfree(fcall);
1016
1017         return retval;
1018 }
1019
1020 /**
1021  * v9fs_readlink - read a symlink's location (internal version)
1022  * @dentry: dentry for symlink
1023  * @buffer: buffer to load symlink location into
1024  * @buflen: length of buffer
1025  *
1026  */
1027
1028 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1029 {
1030         int retval = -EPERM;
1031
1032         struct v9fs_fcall *fcall = NULL;
1033         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
1034         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
1035
1036         if (!fid) {
1037                 dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n");
1038                 retval = -EBADF;
1039                 goto FreeFcall;
1040         }
1041
1042         if (!v9ses->extended) {
1043                 retval = -EBADF;
1044                 dprintk(DEBUG_ERROR, "not extended\n");
1045                 goto FreeFcall;
1046         }
1047
1048         dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name);
1049         retval = v9fs_t_stat(v9ses, fid->fid, &fcall);
1050
1051         if (retval < 0) {
1052                 dprintk(DEBUG_ERROR, "stat error\n");
1053                 goto FreeFcall;
1054         }
1055
1056         if (!fcall)
1057                 return -EIO;
1058
1059         if (!(fcall->params.rstat.stat->mode & V9FS_DMSYMLINK)) {
1060                 retval = -EINVAL;
1061                 goto FreeFcall;
1062         }
1063
1064         /* copy extension buffer into buffer */
1065         if (strlen(fcall->params.rstat.stat->extension) < buflen)
1066                 buflen = strlen(fcall->params.rstat.stat->extension);
1067
1068         memcpy(buffer, fcall->params.rstat.stat->extension, buflen + 1);
1069
1070         retval = buflen;
1071
1072       FreeFcall:
1073         kfree(fcall);
1074
1075         return retval;
1076 }
1077
1078 /**
1079  * v9fs_vfs_readlink - read a symlink's location
1080  * @dentry: dentry for symlink
1081  * @buf: buffer to load symlink location into
1082  * @buflen: length of buffer
1083  *
1084  */
1085
1086 static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
1087                              int buflen)
1088 {
1089         int retval;
1090         int ret;
1091         char *link = __getname();
1092
1093         if (buflen > PATH_MAX)
1094                 buflen = PATH_MAX;
1095
1096         dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
1097
1098         retval = v9fs_readlink(dentry, link, buflen);
1099
1100         if (retval > 0) {
1101                 if ((ret = copy_to_user(buffer, link, retval)) != 0) {
1102                         dprintk(DEBUG_ERROR, "problem copying to user: %d\n",
1103                                 ret);
1104                         retval = ret;
1105                 }
1106         }
1107
1108         putname(link);
1109         return retval;
1110 }
1111
1112 /**
1113  * v9fs_vfs_follow_link - follow a symlink path
1114  * @dentry: dentry for symlink
1115  * @nd: nameidata
1116  *
1117  */
1118
1119 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1120 {
1121         int len = 0;
1122         char *link = __getname();
1123
1124         dprintk(DEBUG_VFS, "%s n", dentry->d_name.name);
1125
1126         if (!link)
1127                 link = ERR_PTR(-ENOMEM);
1128         else {
1129                 len = v9fs_readlink(dentry, link, strlen(link));
1130
1131                 if (len < 0) {
1132                         putname(link);
1133                         link = ERR_PTR(len);
1134                 } else
1135                         link[len] = 0;
1136         }
1137         nd_set_link(nd, link);
1138
1139         return NULL;
1140 }
1141
1142 /**
1143  * v9fs_vfs_put_link - release a symlink path
1144  * @dentry: dentry for symlink
1145  * @nd: nameidata
1146  *
1147  */
1148
1149 static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1150 {
1151         char *s = nd_get_link(nd);
1152
1153         dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
1154         if (!IS_ERR(s))
1155                 putname(s);
1156 }
1157
1158 /**
1159  * v9fs_vfs_link - create a hardlink
1160  * @old_dentry: dentry for file to link to
1161  * @dir: inode destination for new link
1162  * @dentry: dentry for link
1163  *
1164  */
1165
1166 /* XXX - lots of code dup'd from symlink and creates,
1167  * figure out a better reuse strategy
1168  */
1169
1170 static int
1171 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1172               struct dentry *dentry)
1173 {
1174         int retval = -EPERM;
1175         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1176         struct v9fs_fcall *fcall = NULL;
1177         struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
1178         struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry);
1179         struct v9fs_fid *newfid = NULL;
1180         char *symname = __getname();
1181
1182         dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1183                 old_dentry->d_name.name);
1184
1185         if (!v9ses->extended) {
1186                 dprintk(DEBUG_ERROR, "not extended\n");
1187                 goto FreeMem;
1188         }
1189
1190         /* get fid of old_dentry */
1191         sprintf(symname, "hardlink(%d)\n", oldfid->fid);
1192
1193         /* issue a create */
1194         retval = v9fs_create(dir, dentry, V9FS_DMLINK, 0);
1195         if (retval != 0)
1196                 goto FreeMem;
1197
1198         newfid = v9fs_fid_lookup(dentry);
1199         if (!newfid) {
1200                 dprintk(DEBUG_ERROR, "couldn't resolve fid from dentry\n");
1201                 goto FreeMem;
1202         }
1203
1204         /* issue a twstat */
1205         v9fs_blank_mistat(v9ses, mistat);
1206         strcpy(mistat->data + 1, symname);
1207         mistat->extension = mistat->data + 1;
1208         retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
1209         if (retval < 0) {
1210                 dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
1211                         FCALL_ERROR(fcall));
1212                 goto FreeMem;
1213         }
1214
1215         kfree(fcall);
1216
1217         if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
1218                 dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
1219                         FCALL_ERROR(fcall));
1220                 goto FreeMem;
1221         }
1222
1223         d_drop(dentry);         /* FID - will this also clunk? */
1224
1225         kfree(fcall);
1226         fcall = NULL;
1227
1228       FreeMem:
1229         kfree(mistat);
1230         kfree(fcall);
1231         putname(symname);
1232         return retval;
1233 }
1234
1235 /**
1236  * v9fs_vfs_mknod - create a special file
1237  * @dir: inode destination for new link
1238  * @dentry: dentry for file
1239  * @mode: mode for creation
1240  * @dev_t: device associated with special file
1241  *
1242  */
1243
1244 static int
1245 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1246 {
1247         int retval = -EPERM;
1248         struct v9fs_fid *newfid;
1249         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1250         struct v9fs_fcall *fcall = NULL;
1251         struct v9fs_stat *mistat = kmalloc(v9ses->maxdata, GFP_KERNEL);
1252         char *symname = __getname();
1253
1254         dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1255                 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1256
1257         if (!mistat)
1258                 return -ENOMEM;
1259
1260         if (!new_valid_dev(rdev)) {
1261                 retval = -EINVAL;
1262                 goto FreeMem;
1263         }
1264
1265         if (!v9ses->extended) {
1266                 dprintk(DEBUG_ERROR, "not extended\n");
1267                 goto FreeMem;
1268         }
1269
1270         /* issue a create */
1271         retval = v9fs_create(dir, dentry, mode, 0);
1272
1273         if (retval != 0)
1274                 goto FreeMem;
1275
1276         newfid = v9fs_fid_lookup(dentry);
1277         if (!newfid) {
1278                 dprintk(DEBUG_ERROR, "coudn't resove fid from dentry\n");
1279                 retval = -EINVAL;
1280                 goto FreeMem;
1281         }
1282
1283         /* build extension */
1284         if (S_ISBLK(mode))
1285                 sprintf(symname, "b %u %u", MAJOR(rdev), MINOR(rdev));
1286         else if (S_ISCHR(mode))
1287                 sprintf(symname, "c %u %u", MAJOR(rdev), MINOR(rdev));
1288         else if (S_ISFIFO(mode))
1289                 ;       /* DO NOTHING */
1290         else {
1291                 retval = -EINVAL;
1292                 goto FreeMem;
1293         }
1294
1295         if (!S_ISFIFO(mode)) {
1296                 /* issue a twstat */
1297                 v9fs_blank_mistat(v9ses, mistat);
1298                 strcpy(mistat->data + 1, symname);
1299                 mistat->extension = mistat->data + 1;
1300                 retval = v9fs_t_wstat(v9ses, newfid->fid, mistat, &fcall);
1301                 if (retval < 0) {
1302                         dprintk(DEBUG_ERROR, "v9fs_t_wstat error: %s\n",
1303                                 FCALL_ERROR(fcall));
1304                         goto FreeMem;
1305                 }
1306         }
1307
1308         /* need to update dcache so we show up */
1309         kfree(fcall);
1310
1311         if (v9fs_t_clunk(v9ses, newfid->fid, &fcall)) {
1312                 dprintk(DEBUG_ERROR, "clunk for symlink failed: %s\n",
1313                         FCALL_ERROR(fcall));
1314                 goto FreeMem;
1315         }
1316
1317         d_drop(dentry);         /* FID - will this also clunk? */
1318
1319       FreeMem:
1320         kfree(mistat);
1321         kfree(fcall);
1322         putname(symname);
1323
1324         return retval;
1325 }
1326
1327 static struct inode_operations v9fs_dir_inode_operations_ext = {
1328         .create = v9fs_vfs_create,
1329         .lookup = v9fs_vfs_lookup,
1330         .symlink = v9fs_vfs_symlink,
1331         .link = v9fs_vfs_link,
1332         .unlink = v9fs_vfs_unlink,
1333         .mkdir = v9fs_vfs_mkdir,
1334         .rmdir = v9fs_vfs_rmdir,
1335         .mknod = v9fs_vfs_mknod,
1336         .rename = v9fs_vfs_rename,
1337         .readlink = v9fs_vfs_readlink,
1338         .getattr = v9fs_vfs_getattr,
1339         .setattr = v9fs_vfs_setattr,
1340 };
1341
1342 static struct inode_operations v9fs_dir_inode_operations = {
1343         .create = v9fs_vfs_create,
1344         .lookup = v9fs_vfs_lookup,
1345         .unlink = v9fs_vfs_unlink,
1346         .mkdir = v9fs_vfs_mkdir,
1347         .rmdir = v9fs_vfs_rmdir,
1348         .mknod = v9fs_vfs_mknod,
1349         .rename = v9fs_vfs_rename,
1350         .getattr = v9fs_vfs_getattr,
1351         .setattr = v9fs_vfs_setattr,
1352 };
1353
1354 static struct inode_operations v9fs_file_inode_operations = {
1355         .getattr = v9fs_vfs_getattr,
1356         .setattr = v9fs_vfs_setattr,
1357 };
1358
1359 static struct inode_operations v9fs_symlink_inode_operations = {
1360         .readlink = v9fs_vfs_readlink,
1361         .follow_link = v9fs_vfs_follow_link,
1362         .put_link = v9fs_vfs_put_link,
1363         .getattr = v9fs_vfs_getattr,
1364         .setattr = v9fs_vfs_setattr,
1365 };