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Merge branch 'linux-3.9'
[zfs] / module / spl / spl-vnode.c
1 /*****************************************************************************\
2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
3  *  Copyright (C) 2007 The Regents of the University of California.
4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
6  *  UCRL-CODE-235197
7  *
8  *  This file is part of the SPL, Solaris Porting Layer.
9  *  For details, see <http://zfsonlinux.org/>.
10  *
11  *  The SPL is free software; you can redistribute it and/or modify it
12  *  under the terms of the GNU General Public License as published by the
13  *  Free Software Foundation; either version 2 of the License, or (at your
14  *  option) any later version.
15  *
16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
19  *  for more details.
20  *
21  *  You should have received a copy of the GNU General Public License along
22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
23  *****************************************************************************
24  *  Solaris Porting Layer (SPL) Vnode Implementation.
25 \*****************************************************************************/
26
27 #include <sys/vnode.h>
28 #include <linux/falloc.h>
29 #include <spl-debug.h>
30
31 #ifdef SS_DEBUG_SUBSYS
32 #undef SS_DEBUG_SUBSYS
33 #endif
34
35 #define SS_DEBUG_SUBSYS SS_VNODE
36
37 vnode_t *rootdir = (vnode_t *)0xabcd1234;
38 EXPORT_SYMBOL(rootdir);
39
40 static spl_kmem_cache_t *vn_cache;
41 static spl_kmem_cache_t *vn_file_cache;
42
43 static DEFINE_SPINLOCK(vn_file_lock);
44 static LIST_HEAD(vn_file_list);
45
46 #ifdef HAVE_KERN_PATH_PARENT_HEADER
47 #ifndef HAVE_KERN_PATH_PARENT_SYMBOL
48 kern_path_parent_t kern_path_parent_fn = SYMBOL_POISON;
49 EXPORT_SYMBOL(kern_path_parent_fn);
50 #endif /* HAVE_KERN_PATH_PARENT_SYMBOL */
51 #endif /* HAVE_KERN_PATH_PARENT_HEADER */
52
53 #ifdef HAVE_KERN_PATH_LOCKED
54 kern_path_locked_t kern_path_locked_fn = SYMBOL_POISON;
55 #endif /* HAVE_KERN_PATH_LOCKED */
56
57 vtype_t
58 vn_mode_to_vtype(mode_t mode)
59 {
60         if (S_ISREG(mode))
61                 return VREG;
62
63         if (S_ISDIR(mode))
64                 return VDIR;
65
66         if (S_ISCHR(mode))
67                 return VCHR;
68
69         if (S_ISBLK(mode))
70                 return VBLK;
71
72         if (S_ISFIFO(mode))
73                 return VFIFO;
74
75         if (S_ISLNK(mode))
76                 return VLNK;
77
78         if (S_ISSOCK(mode))
79                 return VSOCK;
80
81         if (S_ISCHR(mode))
82                 return VCHR;
83
84         return VNON;
85 } /* vn_mode_to_vtype() */
86 EXPORT_SYMBOL(vn_mode_to_vtype);
87
88 mode_t
89 vn_vtype_to_mode(vtype_t vtype)
90 {
91         if (vtype == VREG)
92                 return S_IFREG;
93
94         if (vtype == VDIR)
95                 return S_IFDIR;
96
97         if (vtype == VCHR)
98                 return S_IFCHR;
99
100         if (vtype == VBLK)
101                 return S_IFBLK;
102
103         if (vtype == VFIFO)
104                 return S_IFIFO;
105
106         if (vtype == VLNK)
107                 return S_IFLNK;
108
109         if (vtype == VSOCK)
110                 return S_IFSOCK;
111
112         return VNON;
113 } /* vn_vtype_to_mode() */
114 EXPORT_SYMBOL(vn_vtype_to_mode);
115
116 vnode_t *
117 vn_alloc(int flag)
118 {
119         vnode_t *vp;
120         SENTRY;
121
122         vp = kmem_cache_alloc(vn_cache, flag);
123         if (vp != NULL) {
124                 vp->v_file = NULL;
125                 vp->v_type = 0;
126         }
127
128         SRETURN(vp);
129 } /* vn_alloc() */
130 EXPORT_SYMBOL(vn_alloc);
131
132 void
133 vn_free(vnode_t *vp)
134 {
135         SENTRY;
136         kmem_cache_free(vn_cache, vp);
137         SEXIT;
138 } /* vn_free() */
139 EXPORT_SYMBOL(vn_free);
140
141 int
142 vn_open(const char *path, uio_seg_t seg, int flags, int mode,
143         vnode_t **vpp, int x1, void *x2)
144 {
145         struct file *fp;
146         struct kstat stat;
147         int rc, saved_umask = 0;
148         gfp_t saved_gfp;
149         vnode_t *vp;
150         SENTRY;
151
152         ASSERT(flags & (FWRITE | FREAD));
153         ASSERT(seg == UIO_SYSSPACE);
154         ASSERT(vpp);
155         *vpp = NULL;
156
157         if (!(flags & FCREAT) && (flags & FWRITE))
158                 flags |= FEXCL;
159
160         /* Note for filp_open() the two low bits must be remapped to mean:
161          * 01 - read-only  -> 00 read-only
162          * 10 - write-only -> 01 write-only
163          * 11 - read-write -> 10 read-write
164          */
165         flags--;
166
167         if (flags & FCREAT)
168                 saved_umask = xchg(&current->fs->umask, 0);
169
170         fp = filp_open(path, flags, mode);
171
172         if (flags & FCREAT)
173                 (void)xchg(&current->fs->umask, saved_umask);
174
175         if (IS_ERR(fp))
176                 SRETURN(-PTR_ERR(fp));
177
178 #ifdef HAVE_2ARGS_VFS_GETATTR
179         rc = vfs_getattr(&fp->f_path, &stat);
180 #else
181         rc = vfs_getattr(fp->f_path.mnt, fp->f_dentry, &stat);
182 #endif
183         if (rc) {
184                 filp_close(fp, 0);
185                 SRETURN(-rc);
186         }
187
188         vp = vn_alloc(KM_SLEEP);
189         if (!vp) {
190                 filp_close(fp, 0);
191                 SRETURN(ENOMEM);
192         }
193
194         saved_gfp = mapping_gfp_mask(fp->f_mapping);
195         mapping_set_gfp_mask(fp->f_mapping, saved_gfp & ~(__GFP_IO|__GFP_FS));
196
197         mutex_enter(&vp->v_lock);
198         vp->v_type = vn_mode_to_vtype(stat.mode);
199         vp->v_file = fp;
200         vp->v_gfp_mask = saved_gfp;
201         *vpp = vp;
202         mutex_exit(&vp->v_lock);
203
204         SRETURN(0);
205 } /* vn_open() */
206 EXPORT_SYMBOL(vn_open);
207
208 int
209 vn_openat(const char *path, uio_seg_t seg, int flags, int mode,
210           vnode_t **vpp, int x1, void *x2, vnode_t *vp, int fd)
211 {
212         char *realpath;
213         int len, rc;
214         SENTRY;
215
216         ASSERT(vp == rootdir);
217
218         len = strlen(path) + 2;
219         realpath = kmalloc(len, GFP_KERNEL);
220         if (!realpath)
221                 SRETURN(ENOMEM);
222
223         (void)snprintf(realpath, len, "/%s", path);
224         rc = vn_open(realpath, seg, flags, mode, vpp, x1, x2);
225         kfree(realpath);
226
227         SRETURN(rc);
228 } /* vn_openat() */
229 EXPORT_SYMBOL(vn_openat);
230
231 int
232 vn_rdwr(uio_rw_t uio, vnode_t *vp, void *addr, ssize_t len, offset_t off,
233         uio_seg_t seg, int ioflag, rlim64_t x2, void *x3, ssize_t *residp)
234 {
235         loff_t offset;
236         mm_segment_t saved_fs;
237         struct file *fp;
238         int rc;
239         SENTRY;
240
241         ASSERT(uio == UIO_WRITE || uio == UIO_READ);
242         ASSERT(vp);
243         ASSERT(vp->v_file);
244         ASSERT(seg == UIO_SYSSPACE);
245         ASSERT((ioflag & ~FAPPEND) == 0);
246         ASSERT(x2 == RLIM64_INFINITY);
247
248         fp = vp->v_file;
249
250         offset = off;
251         if (ioflag & FAPPEND)
252                 offset = fp->f_pos;
253
254         /* Writable user data segment must be briefly increased for this
255          * process so we can use the user space read call paths to write
256          * in to memory allocated by the kernel. */
257         saved_fs = get_fs();
258         set_fs(get_ds());
259
260         if (uio & UIO_WRITE)
261                 rc = vfs_write(fp, addr, len, &offset);
262         else
263                 rc = vfs_read(fp, addr, len, &offset);
264
265         set_fs(saved_fs);
266         fp->f_pos = offset;
267
268         if (rc < 0)
269                 SRETURN(-rc);
270
271         if (residp) {
272                 *residp = len - rc;
273         } else {
274                 if (rc != len)
275                         SRETURN(EIO);
276         }
277
278         SRETURN(0);
279 } /* vn_rdwr() */
280 EXPORT_SYMBOL(vn_rdwr);
281
282 int
283 vn_close(vnode_t *vp, int flags, int x1, int x2, void *x3, void *x4)
284 {
285         int rc;
286         SENTRY;
287
288         ASSERT(vp);
289         ASSERT(vp->v_file);
290
291         mapping_set_gfp_mask(vp->v_file->f_mapping, vp->v_gfp_mask);
292         rc = filp_close(vp->v_file, 0);
293         vn_free(vp);
294
295         SRETURN(-rc);
296 } /* vn_close() */
297 EXPORT_SYMBOL(vn_close);
298
299 /* vn_seek() does not actually seek it only performs bounds checking on the
300  * proposed seek.  We perform minimal checking and allow vn_rdwr() to catch
301  * anything more serious. */
302 int
303 vn_seek(vnode_t *vp, offset_t ooff, offset_t *noffp, void *ct)
304 {
305         return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
306 }
307 EXPORT_SYMBOL(vn_seek);
308
309 #ifdef HAVE_KERN_PATH_LOCKED
310 /* Based on do_unlinkat() from linux/fs/namei.c */
311 int
312 vn_remove(const char *path, uio_seg_t seg, int flags)
313 {
314         struct dentry *dentry;
315         struct path parent;
316         struct inode *inode = NULL;
317         int rc = 0;
318         SENTRY;
319
320         ASSERT(seg == UIO_SYSSPACE);
321         ASSERT(flags == RMFILE);
322
323         dentry = spl_kern_path_locked(path, &parent);
324         rc = PTR_ERR(dentry);
325         if (!IS_ERR(dentry)) {
326                 if (parent.dentry->d_name.name[parent.dentry->d_name.len])
327                         SGOTO(slashes, rc = 0);
328
329                 inode = dentry->d_inode;
330                 if (!inode)
331                         SGOTO(slashes, rc = 0);
332
333                 if (inode)
334                         ihold(inode);
335
336                 rc = vfs_unlink(parent.dentry->d_inode, dentry);
337 exit1:
338                 dput(dentry);
339         } else {
340                 return (-rc);
341         }
342
343         spl_inode_unlock(parent.dentry->d_inode);
344         if (inode)
345                 iput(inode);    /* truncate the inode here */
346
347         path_put(&parent);
348         SRETURN(-rc);
349
350 slashes:
351         rc = !dentry->d_inode ? -ENOENT :
352             S_ISDIR(dentry->d_inode->i_mode) ? -EISDIR : -ENOTDIR;
353         SGOTO(exit1, rc);
354 } /* vn_remove() */
355 EXPORT_SYMBOL(vn_remove);
356
357 /* Based on do_rename() from linux/fs/namei.c */
358 int
359 vn_rename(const char *oldname, const char *newname, int x1)
360 {
361         struct dentry *old_dir, *new_dir;
362         struct dentry *old_dentry, *new_dentry;
363         struct dentry *trap;
364         struct path old_parent, new_parent;
365         int rc = 0;
366         SENTRY;
367
368         old_dentry = spl_kern_path_locked(oldname, &old_parent);
369         if (IS_ERR(old_dentry))
370                 SGOTO(exit, rc = PTR_ERR(old_dentry));
371
372         spl_inode_unlock(old_parent.dentry->d_inode);
373
374         new_dentry = spl_kern_path_locked(newname, &new_parent);
375         if (IS_ERR(new_dentry))
376                 SGOTO(exit2, rc = PTR_ERR(new_dentry));
377
378         spl_inode_unlock(new_parent.dentry->d_inode);
379
380         rc = -EXDEV;
381         if (old_parent.mnt != new_parent.mnt)
382                 SGOTO(exit3, rc);
383
384         old_dir = old_parent.dentry;
385         new_dir = new_parent.dentry;
386         trap = lock_rename(new_dir, old_dir);
387
388         /* source should not be ancestor of target */
389         rc = -EINVAL;
390         if (old_dentry == trap)
391                 SGOTO(exit4, rc);
392
393         /* target should not be an ancestor of source */
394         rc = -ENOTEMPTY;
395         if (new_dentry == trap)
396                 SGOTO(exit4, rc);
397
398         /* source must exist */
399         rc = -ENOENT;
400         if (!old_dentry->d_inode)
401                 SGOTO(exit4, rc);
402
403         /* unless the source is a directory trailing slashes give -ENOTDIR */
404         if (!S_ISDIR(old_dentry->d_inode->i_mode)) {
405                 rc = -ENOTDIR;
406                 if (old_dentry->d_name.name[old_dentry->d_name.len])
407                         SGOTO(exit4, rc);
408                 if (new_dentry->d_name.name[new_dentry->d_name.len])
409                         SGOTO(exit4, rc);
410         }
411
412 #ifdef HAVE_4ARGS_VFS_RENAME
413         rc = vfs_rename(old_dir->d_inode, old_dentry,
414                         new_dir->d_inode, new_dentry);
415 #else
416         rc = vfs_rename(old_dir->d_inode, old_dentry, oldnd.nd_mnt,
417                         new_dir->d_inode, new_dentry, newnd.nd_mnt);
418 #endif /* HAVE_4ARGS_VFS_RENAME */
419 exit4:
420         unlock_rename(new_dir, old_dir);
421 exit3:
422         dput(new_dentry);
423         path_put(&new_parent);
424 exit2:
425         dput(old_dentry);
426         path_put(&old_parent);
427 exit:
428         SRETURN(-rc);
429 }
430 EXPORT_SYMBOL(vn_rename);
431
432 #else
433 static struct dentry *
434 vn_lookup_hash(struct nameidata *nd)
435 {
436         return lookup_one_len((const char *)nd->last.name,
437                               nd->nd_dentry, nd->last.len);
438 } /* lookup_hash() */
439
440 static void
441 vn_path_release(struct nameidata *nd)
442 {
443         dput(nd->nd_dentry);
444         mntput(nd->nd_mnt);
445 }
446
447 /* Modified do_unlinkat() from linux/fs/namei.c, only uses exported symbols */
448 int
449 vn_remove(const char *path, uio_seg_t seg, int flags)
450 {
451         struct dentry *dentry;
452         struct nameidata nd;
453         struct inode *inode = NULL;
454         int rc = 0;
455         SENTRY;
456
457         ASSERT(seg == UIO_SYSSPACE);
458         ASSERT(flags == RMFILE);
459
460         rc = spl_kern_path_parent(path, &nd);
461         if (rc)
462                 SGOTO(exit, rc);
463
464         rc = -EISDIR;
465         if (nd.last_type != LAST_NORM)
466                 SGOTO(exit1, rc);
467
468         spl_inode_lock_nested(nd.nd_dentry->d_inode, I_MUTEX_PARENT);
469         dentry = vn_lookup_hash(&nd);
470         rc = PTR_ERR(dentry);
471         if (!IS_ERR(dentry)) {
472                 /* Why not before? Because we want correct rc value */
473                 if (nd.last.name[nd.last.len])
474                         SGOTO(slashes, rc);
475
476                 inode = dentry->d_inode;
477                 if (inode)
478                         atomic_inc(&inode->i_count);
479 #ifdef HAVE_2ARGS_VFS_UNLINK
480                 rc = vfs_unlink(nd.nd_dentry->d_inode, dentry);
481 #else
482                 rc = vfs_unlink(nd.nd_dentry->d_inode, dentry, nd.nd_mnt);
483 #endif /* HAVE_2ARGS_VFS_UNLINK */
484 exit2:
485                 dput(dentry);
486         }
487
488         spl_inode_unlock(nd.nd_dentry->d_inode);
489         if (inode)
490                 iput(inode);    /* truncate the inode here */
491 exit1:
492         vn_path_release(&nd);
493 exit:
494         SRETURN(-rc);
495
496 slashes:
497         rc = !dentry->d_inode ? -ENOENT :
498                 S_ISDIR(dentry->d_inode->i_mode) ? -EISDIR : -ENOTDIR;
499         SGOTO(exit2, rc);
500 } /* vn_remove() */
501 EXPORT_SYMBOL(vn_remove);
502
503 /* Modified do_rename() from linux/fs/namei.c, only uses exported symbols */
504 int
505 vn_rename(const char *oldname, const char *newname, int x1)
506 {
507         struct dentry *old_dir, *new_dir;
508         struct dentry *old_dentry, *new_dentry;
509         struct dentry *trap;
510         struct nameidata oldnd, newnd;
511         int rc = 0;
512         SENTRY;
513
514         rc = spl_kern_path_parent(oldname, &oldnd);
515         if (rc)
516                 SGOTO(exit, rc);
517
518         rc = spl_kern_path_parent(newname, &newnd);
519         if (rc)
520                 SGOTO(exit1, rc);
521
522         rc = -EXDEV;
523         if (oldnd.nd_mnt != newnd.nd_mnt)
524                 SGOTO(exit2, rc);
525
526         old_dir = oldnd.nd_dentry;
527         rc = -EBUSY;
528         if (oldnd.last_type != LAST_NORM)
529                 SGOTO(exit2, rc);
530
531         new_dir = newnd.nd_dentry;
532         if (newnd.last_type != LAST_NORM)
533                 SGOTO(exit2, rc);
534
535         trap = lock_rename(new_dir, old_dir);
536
537         old_dentry = vn_lookup_hash(&oldnd);
538
539         rc = PTR_ERR(old_dentry);
540         if (IS_ERR(old_dentry))
541                 SGOTO(exit3, rc);
542
543         /* source must exist */
544         rc = -ENOENT;
545         if (!old_dentry->d_inode)
546                 SGOTO(exit4, rc);
547
548         /* unless the source is a directory trailing slashes give -ENOTDIR */
549         if (!S_ISDIR(old_dentry->d_inode->i_mode)) {
550                 rc = -ENOTDIR;
551                 if (oldnd.last.name[oldnd.last.len])
552                         SGOTO(exit4, rc);
553                 if (newnd.last.name[newnd.last.len])
554                         SGOTO(exit4, rc);
555         }
556
557         /* source should not be ancestor of target */
558         rc = -EINVAL;
559         if (old_dentry == trap)
560                 SGOTO(exit4, rc);
561
562         new_dentry = vn_lookup_hash(&newnd);
563         rc = PTR_ERR(new_dentry);
564         if (IS_ERR(new_dentry))
565                 SGOTO(exit4, rc);
566
567         /* target should not be an ancestor of source */
568         rc = -ENOTEMPTY;
569         if (new_dentry == trap)
570                 SGOTO(exit5, rc);
571
572 #ifdef HAVE_4ARGS_VFS_RENAME
573         rc = vfs_rename(old_dir->d_inode, old_dentry,
574                         new_dir->d_inode, new_dentry);
575 #else
576         rc = vfs_rename(old_dir->d_inode, old_dentry, oldnd.nd_mnt,
577                         new_dir->d_inode, new_dentry, newnd.nd_mnt);
578 #endif /* HAVE_4ARGS_VFS_RENAME */
579 exit5:
580         dput(new_dentry);
581 exit4:
582         dput(old_dentry);
583 exit3:
584         unlock_rename(new_dir, old_dir);
585 exit2:
586         vn_path_release(&newnd);
587 exit1:
588         vn_path_release(&oldnd);
589 exit:
590         SRETURN(-rc);
591 }
592 EXPORT_SYMBOL(vn_rename);
593 #endif /* HAVE_KERN_PATH_LOCKED */
594
595 int
596 vn_getattr(vnode_t *vp, vattr_t *vap, int flags, void *x3, void *x4)
597 {
598         struct file *fp;
599         struct kstat stat;
600         int rc;
601         SENTRY;
602
603         ASSERT(vp);
604         ASSERT(vp->v_file);
605         ASSERT(vap);
606
607         fp = vp->v_file;
608
609 #ifdef HAVE_2ARGS_VFS_GETATTR
610         rc = vfs_getattr(&fp->f_path, &stat);
611 #else
612         rc = vfs_getattr(fp->f_path.mnt, fp->f_dentry, &stat);
613 #endif
614         if (rc)
615                 SRETURN(-rc);
616
617         vap->va_type          = vn_mode_to_vtype(stat.mode);
618         vap->va_mode          = stat.mode;
619         vap->va_uid           = stat.uid;
620         vap->va_gid           = stat.gid;
621         vap->va_fsid          = 0;
622         vap->va_nodeid        = stat.ino;
623         vap->va_nlink         = stat.nlink;
624         vap->va_size          = stat.size;
625         vap->va_blksize       = stat.blksize;
626         vap->va_atime         = stat.atime;
627         vap->va_mtime         = stat.mtime;
628         vap->va_ctime         = stat.ctime;
629         vap->va_rdev          = stat.rdev;
630         vap->va_nblocks       = stat.blocks;
631
632         SRETURN(0);
633 }
634 EXPORT_SYMBOL(vn_getattr);
635
636 int vn_fsync(vnode_t *vp, int flags, void *x3, void *x4)
637 {
638         int datasync = 0;
639         SENTRY;
640
641         ASSERT(vp);
642         ASSERT(vp->v_file);
643
644         if (flags & FDSYNC)
645                 datasync = 1;
646
647         SRETURN(-spl_filp_fsync(vp->v_file, datasync));
648 } /* vn_fsync() */
649 EXPORT_SYMBOL(vn_fsync);
650
651 int vn_space(vnode_t *vp, int cmd, struct flock *bfp, int flag,
652     offset_t offset, void *x6, void *x7)
653 {
654         int error = EOPNOTSUPP;
655         SENTRY;
656
657         if (cmd != F_FREESP || bfp->l_whence != 0)
658                 SRETURN(EOPNOTSUPP);
659
660         ASSERT(vp);
661         ASSERT(vp->v_file);
662         ASSERT(bfp->l_start >= 0 && bfp->l_len > 0);
663
664 #ifdef FALLOC_FL_PUNCH_HOLE
665         /*
666          * When supported by the underlying file system preferentially
667          * use the fallocate() callback to preallocate the space.
668          */
669         error = -spl_filp_fallocate(vp->v_file,
670             FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
671             bfp->l_start, bfp->l_len);
672         if (error == 0)
673                 SRETURN(0);
674 #endif
675
676 #ifdef HAVE_INODE_TRUNCATE_RANGE
677         if (vp->v_file->f_dentry && vp->v_file->f_dentry->d_inode &&
678             vp->v_file->f_dentry->d_inode->i_op &&
679             vp->v_file->f_dentry->d_inode->i_op->truncate_range) {
680                 off_t end = bfp->l_start + bfp->l_len;
681                 /*
682                  * Judging from the code in shmem_truncate_range(),
683                  * it seems the kernel expects the end offset to be
684                  * inclusive and aligned to the end of a page.
685                  */
686                 if (end % PAGE_SIZE != 0) {
687                         end &= ~(off_t)(PAGE_SIZE - 1);
688                         if (end <= bfp->l_start)
689                                 SRETURN(0);
690                 }
691                 --end;
692
693                 vp->v_file->f_dentry->d_inode->i_op->truncate_range(
694                         vp->v_file->f_dentry->d_inode,
695                         bfp->l_start, end
696                 );
697                 SRETURN(0);
698         }
699 #endif
700
701         SRETURN(error);
702 }
703 EXPORT_SYMBOL(vn_space);
704
705 /* Function must be called while holding the vn_file_lock */
706 static file_t *
707 file_find(int fd)
708 {
709         file_t *fp;
710
711         ASSERT(spin_is_locked(&vn_file_lock));
712
713         list_for_each_entry(fp, &vn_file_list,  f_list) {
714                 if (fd == fp->f_fd && fp->f_task == current) {
715                         ASSERT(atomic_read(&fp->f_ref) != 0);
716                         return fp;
717                 }
718         }
719
720         return NULL;
721 } /* file_find() */
722
723 file_t *
724 vn_getf(int fd)
725 {
726         struct kstat stat;
727         struct file *lfp;
728         file_t *fp;
729         vnode_t *vp;
730         int rc = 0;
731         SENTRY;
732
733         /* Already open just take an extra reference */
734         spin_lock(&vn_file_lock);
735
736         fp = file_find(fd);
737         if (fp) {
738                 atomic_inc(&fp->f_ref);
739                 spin_unlock(&vn_file_lock);
740                 SRETURN(fp);
741         }
742
743         spin_unlock(&vn_file_lock);
744
745         /* File was not yet opened create the object and setup */
746         fp = kmem_cache_alloc(vn_file_cache, KM_SLEEP);
747         if (fp == NULL)
748                 SGOTO(out, rc);
749
750         mutex_enter(&fp->f_lock);
751
752         fp->f_fd = fd;
753         fp->f_task = current;
754         fp->f_offset = 0;
755         atomic_inc(&fp->f_ref);
756
757         lfp = fget(fd);
758         if (lfp == NULL)
759                 SGOTO(out_mutex, rc);
760
761         vp = vn_alloc(KM_SLEEP);
762         if (vp == NULL)
763                 SGOTO(out_fget, rc);
764
765 #ifdef HAVE_2ARGS_VFS_GETATTR
766         rc = vfs_getattr(&lfp->f_path, &stat);
767 #else
768         rc = vfs_getattr(lfp->f_path.mnt, lfp->f_dentry, &stat);
769 #endif
770         if (rc)
771                 SGOTO(out_vnode, rc);
772
773         mutex_enter(&vp->v_lock);
774         vp->v_type = vn_mode_to_vtype(stat.mode);
775         vp->v_file = lfp;
776         mutex_exit(&vp->v_lock);
777
778         fp->f_vnode = vp;
779         fp->f_file = lfp;
780
781         /* Put it on the tracking list */
782         spin_lock(&vn_file_lock);
783         list_add(&fp->f_list, &vn_file_list);
784         spin_unlock(&vn_file_lock);
785
786         mutex_exit(&fp->f_lock);
787         SRETURN(fp);
788
789 out_vnode:
790         vn_free(vp);
791 out_fget:
792         fput(lfp);
793 out_mutex:
794         mutex_exit(&fp->f_lock);
795         kmem_cache_free(vn_file_cache, fp);
796 out:
797         SRETURN(NULL);
798 } /* getf() */
799 EXPORT_SYMBOL(getf);
800
801 static void releasef_locked(file_t *fp)
802 {
803         ASSERT(fp->f_file);
804         ASSERT(fp->f_vnode);
805
806         /* Unlinked from list, no refs, safe to free outside mutex */
807         fput(fp->f_file);
808         vn_free(fp->f_vnode);
809
810         kmem_cache_free(vn_file_cache, fp);
811 }
812
813 void
814 vn_releasef(int fd)
815 {
816         file_t *fp;
817         SENTRY;
818
819         spin_lock(&vn_file_lock);
820         fp = file_find(fd);
821         if (fp) {
822                 atomic_dec(&fp->f_ref);
823                 if (atomic_read(&fp->f_ref) > 0) {
824                         spin_unlock(&vn_file_lock);
825                         SEXIT;
826                         return;
827                 }
828
829                 list_del(&fp->f_list);
830                 releasef_locked(fp);
831         }
832         spin_unlock(&vn_file_lock);
833
834         SEXIT;
835         return;
836 } /* releasef() */
837 EXPORT_SYMBOL(releasef);
838
839 #ifndef HAVE_SET_FS_PWD
840 void
841 #  ifdef HAVE_SET_FS_PWD_WITH_CONST
842 set_fs_pwd(struct fs_struct *fs, const struct path *path)
843 #  else
844 set_fs_pwd(struct fs_struct *fs, struct path *path)
845 #  endif
846 {
847         struct path old_pwd;
848
849 #  ifdef HAVE_FS_STRUCT_SPINLOCK
850         spin_lock(&fs->lock);
851         old_pwd = fs->pwd;
852         fs->pwd = *path;
853         path_get(path);
854         spin_unlock(&fs->lock);
855 #  else
856         write_lock(&fs->lock);
857         old_pwd = fs->pwd;
858         fs->pwd = *path;
859         path_get(path);
860         write_unlock(&fs->lock);
861 #  endif /* HAVE_FS_STRUCT_SPINLOCK */
862
863         if (old_pwd.dentry)
864                 path_put(&old_pwd);
865 }
866 #endif /* HAVE_SET_FS_PWD */
867
868 int
869 vn_set_pwd(const char *filename)
870 {
871 #ifdef HAVE_USER_PATH_DIR
872         struct path path;
873 #else
874         struct nameidata nd;
875 #endif /* HAVE_USER_PATH_DIR */
876         mm_segment_t saved_fs;
877         int rc;
878         SENTRY;
879
880         /*
881          * user_path_dir() and __user_walk() both expect 'filename' to be
882          * a user space address so we must briefly increase the data segment
883          * size to ensure strncpy_from_user() does not fail with -EFAULT.
884          */
885         saved_fs = get_fs();
886         set_fs(get_ds());
887
888 # ifdef HAVE_USER_PATH_DIR
889         rc = user_path_dir(filename, &path);
890         if (rc)
891                 SGOTO(out, rc);
892
893         rc = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_ACCESS);
894         if (rc)
895                 SGOTO(dput_and_out, rc);
896
897         set_fs_pwd(current->fs, &path);
898
899 dput_and_out:
900         path_put(&path);
901 # else
902         rc = __user_walk(filename,
903                          LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_CHDIR, &nd);
904         if (rc)
905                 SGOTO(out, rc);
906
907         rc = vfs_permission(&nd, MAY_EXEC);
908         if (rc)
909                 SGOTO(dput_and_out, rc);
910
911         set_fs_pwd(current->fs, &nd.path);
912
913 dput_and_out:
914         path_put(&nd.path);
915 # endif /* HAVE_USER_PATH_DIR */
916 out:
917         set_fs(saved_fs);
918
919         SRETURN(-rc);
920 } /* vn_set_pwd() */
921 EXPORT_SYMBOL(vn_set_pwd);
922
923 static int
924 vn_cache_constructor(void *buf, void *cdrarg, int kmflags)
925 {
926         struct vnode *vp = buf;
927
928         mutex_init(&vp->v_lock, NULL, MUTEX_DEFAULT, NULL);
929
930         return (0);
931 } /* vn_cache_constructor() */
932
933 static void
934 vn_cache_destructor(void *buf, void *cdrarg)
935 {
936         struct vnode *vp = buf;
937
938         mutex_destroy(&vp->v_lock);
939 } /* vn_cache_destructor() */
940
941 static int
942 vn_file_cache_constructor(void *buf, void *cdrarg, int kmflags)
943 {
944         file_t *fp = buf;
945
946         atomic_set(&fp->f_ref, 0);
947         mutex_init(&fp->f_lock, NULL, MUTEX_DEFAULT, NULL);
948         INIT_LIST_HEAD(&fp->f_list);
949
950         return (0);
951 } /* file_cache_constructor() */
952
953 static void
954 vn_file_cache_destructor(void *buf, void *cdrarg)
955 {
956         file_t *fp = buf;
957
958         mutex_destroy(&fp->f_lock);
959 } /* vn_file_cache_destructor() */
960
961 int spl_vn_init_kallsyms_lookup(void)
962 {
963 #ifdef HAVE_KERN_PATH_PARENT_HEADER
964 #ifndef HAVE_KERN_PATH_PARENT_SYMBOL
965         kern_path_parent_fn = (kern_path_parent_t)
966                 spl_kallsyms_lookup_name("kern_path_parent");
967         if (!kern_path_parent_fn) {
968                 printk(KERN_ERR "Error: Unknown symbol kern_path_parent\n");
969                 return -EFAULT;
970         }
971 #endif /* HAVE_KERN_PATH_PARENT_SYMBOL */
972 #endif /* HAVE_KERN_PATH_PARENT_HEADER */
973
974 #ifdef HAVE_KERN_PATH_LOCKED
975         kern_path_locked_fn = (kern_path_locked_t)
976                 spl_kallsyms_lookup_name("kern_path_locked");
977         if (!kern_path_locked_fn) {
978                 printk(KERN_ERR "Error: Unknown symbol kern_path_locked\n");
979                 return -EFAULT;
980         }
981 #endif
982
983         return (0);
984 }
985
986 int
987 spl_vn_init(void)
988 {
989         SENTRY;
990         vn_cache = kmem_cache_create("spl_vn_cache",
991                                      sizeof(struct vnode), 64,
992                                      vn_cache_constructor,
993                                      vn_cache_destructor,
994                                      NULL, NULL, NULL, KMC_KMEM);
995
996         vn_file_cache = kmem_cache_create("spl_vn_file_cache",
997                                           sizeof(file_t), 64,
998                                           vn_file_cache_constructor,
999                                           vn_file_cache_destructor,
1000                                           NULL, NULL, NULL, KMC_KMEM);
1001         SRETURN(0);
1002 } /* vn_init() */
1003
1004 void
1005 spl_vn_fini(void)
1006 {
1007         file_t *fp, *next_fp;
1008         int leaked = 0;
1009         SENTRY;
1010
1011         spin_lock(&vn_file_lock);
1012
1013         list_for_each_entry_safe(fp, next_fp, &vn_file_list,  f_list) {
1014                 list_del(&fp->f_list);
1015                 releasef_locked(fp);
1016                 leaked++;
1017         }
1018
1019         spin_unlock(&vn_file_lock);
1020
1021         if (leaked > 0)
1022                 SWARN("Warning %d files leaked\n", leaked);
1023
1024         kmem_cache_destroy(vn_file_cache);
1025         kmem_cache_destroy(vn_cache);
1026
1027         SEXIT;
1028         return;
1029 } /* vn_fini() */