3 * Directory operations for Coda filesystem
4 * Original version: (C) 1996 P. Braam and M. Callahan
5 * Rewritten for Linux 2.1. (C) 1997 Carnegie Mellon University
7 * Carnegie Mellon encourages users to contribute improvements to
8 * the Coda project. Contact Peter Braam (coda@cs.cmu.edu).
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <linux/time.h>
15 #include <linux/file.h>
16 #include <linux/stat.h>
17 #include <linux/errno.h>
18 #include <linux/string.h>
19 #include <linux/smp_lock.h>
21 #include <asm/uaccess.h>
23 #include <linux/coda.h>
24 #include <linux/coda_linux.h>
25 #include <linux/coda_psdev.h>
26 #include <linux/coda_fs_i.h>
27 #include <linux/coda_cache.h>
28 #include <linux/coda_proc.h>
33 static int coda_create(struct inode
*dir
, struct dentry
*new, int mode
, struct nameidata
*nd
);
34 static struct dentry
*coda_lookup(struct inode
*dir
, struct dentry
*target
, struct nameidata
*nd
);
35 static int coda_link(struct dentry
*old_dentry
, struct inode
*dir_inode
,
36 struct dentry
*entry
);
37 static int coda_unlink(struct inode
*dir_inode
, struct dentry
*entry
);
38 static int coda_symlink(struct inode
*dir_inode
, struct dentry
*entry
,
40 static int coda_mkdir(struct inode
*dir_inode
, struct dentry
*entry
, int mode
);
41 static int coda_rmdir(struct inode
*dir_inode
, struct dentry
*entry
);
42 static int coda_rename(struct inode
*old_inode
, struct dentry
*old_dentry
,
43 struct inode
*new_inode
, struct dentry
*new_dentry
);
46 static int coda_readdir(struct file
*file
, void *dirent
, filldir_t filldir
);
49 static int coda_dentry_revalidate(struct dentry
*de
, struct nameidata
*nd
);
50 static int coda_dentry_delete(struct dentry
*);
52 /* support routines */
53 static int coda_venus_readdir(struct file
*filp
, filldir_t filldir
,
54 void *dirent
, struct dentry
*dir
);
56 /* same as fs/bad_inode.c */
57 static int coda_return_EIO(void)
61 #define CODA_EIO_ERROR ((void *) (coda_return_EIO))
63 static struct dentry_operations coda_dentry_operations
=
65 .d_revalidate
= coda_dentry_revalidate
,
66 .d_delete
= coda_dentry_delete
,
69 struct inode_operations coda_dir_inode_operations
=
71 .create
= coda_create
,
72 .lookup
= coda_lookup
,
74 .unlink
= coda_unlink
,
75 .symlink
= coda_symlink
,
78 .mknod
= CODA_EIO_ERROR
,
79 .rename
= coda_rename
,
80 .permission
= coda_permission
,
81 .getattr
= coda_getattr
,
82 .setattr
= coda_setattr
,
85 const struct file_operations coda_dir_operations
= {
86 .llseek
= generic_file_llseek
,
87 .read
= generic_read_dir
,
88 .readdir
= coda_readdir
,
91 .release
= coda_release
,
96 /* inode operations for directories */
97 /* access routines: lookup, readlink, permission */
98 static struct dentry
*coda_lookup(struct inode
*dir
, struct dentry
*entry
, struct nameidata
*nd
)
100 struct inode
*res_inode
= NULL
;
101 struct CodaFid resfid
= { { 0, } };
102 int dropme
= 0; /* to indicate entry should not be cached */
105 const char *name
= entry
->d_name
.name
;
106 size_t length
= entry
->d_name
.len
;
108 if ( length
> CODA_MAXNAMLEN
) {
109 printk("name too long: lookup, %s (%*s)\n",
110 coda_i2s(dir
), (int)length
, name
);
111 return ERR_PTR(-ENAMETOOLONG
);
115 /* control object, create inode on the fly */
116 if (coda_isroot(dir
) && coda_iscontrol(name
, length
)) {
117 error
= coda_cnode_makectl(&res_inode
, dir
->i_sb
);
122 error
= venus_lookup(dir
->i_sb
, coda_i2f(dir
),
123 (const char *)name
, length
, &type
, &resfid
);
127 if (type
& CODA_NOCACHE
) {
128 type
&= (~CODA_NOCACHE
);
132 error
= coda_cnode_make(&res_inode
, &resfid
, dir
->i_sb
);
135 return ERR_PTR(error
);
137 } else if (error
!= -ENOENT
) {
139 return ERR_PTR(error
);
144 entry
->d_op
= &coda_dentry_operations
;
145 d_add(entry
, res_inode
);
148 coda_flag_inode(res_inode
, C_VATTR
);
155 int coda_permission(struct inode
*inode
, int mask
, struct nameidata
*nd
)
164 coda_vfs_stat
.permission
++;
166 if (coda_cache_check(inode
, mask
))
169 error
= venus_access(inode
->i_sb
, coda_i2f(inode
), mask
);
172 coda_cache_enter(inode
, mask
);
181 static inline void coda_dir_changed(struct inode
*dir
, int link
)
183 #ifdef REQUERY_VENUS_FOR_MTIME
184 /* invalidate the directory cnode's attributes so we refetch the
185 * attributes from venus next time the inode is referenced */
186 coda_flag_inode(dir
, C_VATTR
);
188 /* optimistically we can also act as if our nose bleeds. The
189 * granularity of the mtime is coarse anyways so we might actually be
190 * right most of the time. Note: we only do this for directories. */
191 dir
->i_mtime
= dir
->i_ctime
= CURRENT_TIME_SEC
;
194 dir
->i_nlink
+= link
;
197 /* creation routines: create, mknod, mkdir, link, symlink */
198 static int coda_create(struct inode
*dir
, struct dentry
*de
, int mode
, struct nameidata
*nd
)
201 const char *name
=de
->d_name
.name
;
202 int length
=de
->d_name
.len
;
204 struct CodaFid newfid
;
205 struct coda_vattr attrs
;
208 coda_vfs_stat
.create
++;
210 if (coda_isroot(dir
) && coda_iscontrol(name
, length
)) {
215 error
= venus_create(dir
->i_sb
, coda_i2f(dir
), name
, length
,
216 0, mode
, &newfid
, &attrs
);
224 inode
= coda_iget(dir
->i_sb
, &newfid
, &attrs
);
225 if ( IS_ERR(inode
) ) {
228 return PTR_ERR(inode
);
231 /* invalidate the directory cnode's attributes */
232 coda_dir_changed(dir
, 0);
234 d_instantiate(de
, inode
);
238 static int coda_mkdir(struct inode
*dir
, struct dentry
*de
, int mode
)
241 struct coda_vattr attrs
;
242 const char *name
= de
->d_name
.name
;
243 int len
= de
->d_name
.len
;
245 struct CodaFid newfid
;
248 coda_vfs_stat
.mkdir
++;
250 if (coda_isroot(dir
) && coda_iscontrol(name
, len
)) {
255 attrs
.va_mode
= mode
;
256 error
= venus_mkdir(dir
->i_sb
, coda_i2f(dir
),
257 name
, len
, &newfid
, &attrs
);
265 inode
= coda_iget(dir
->i_sb
, &newfid
, &attrs
);
266 if ( IS_ERR(inode
) ) {
269 return PTR_ERR(inode
);
272 /* invalidate the directory cnode's attributes */
273 coda_dir_changed(dir
, 1);
275 d_instantiate(de
, inode
);
279 /* try to make de an entry in dir_inodde linked to source_de */
280 static int coda_link(struct dentry
*source_de
, struct inode
*dir_inode
,
283 struct inode
*inode
= source_de
->d_inode
;
284 const char * name
= de
->d_name
.name
;
285 int len
= de
->d_name
.len
;
289 coda_vfs_stat
.link
++;
291 if (coda_isroot(dir_inode
) && coda_iscontrol(name
, len
)) {
296 error
= venus_link(dir_inode
->i_sb
, coda_i2f(inode
),
297 coda_i2f(dir_inode
), (const char *)name
, len
);
304 coda_dir_changed(dir_inode
, 0);
305 atomic_inc(&inode
->i_count
);
306 d_instantiate(de
, inode
);
315 static int coda_symlink(struct inode
*dir_inode
, struct dentry
*de
,
318 const char *name
= de
->d_name
.name
;
319 int len
= de
->d_name
.len
;
324 coda_vfs_stat
.symlink
++;
326 if (coda_isroot(dir_inode
) && coda_iscontrol(name
, len
)) {
331 symlen
= strlen(symname
);
332 if ( symlen
> CODA_MAXPATHLEN
) {
334 return -ENAMETOOLONG
;
338 * This entry is now negative. Since we do not create
339 * an inode for the entry we have to drop it.
342 error
= venus_symlink(dir_inode
->i_sb
, coda_i2f(dir_inode
), name
, len
,
345 /* mtime is no good anymore */
347 coda_dir_changed(dir_inode
, 0);
353 /* destruction routines: unlink, rmdir */
354 int coda_unlink(struct inode
*dir
, struct dentry
*de
)
357 const char *name
= de
->d_name
.name
;
358 int len
= de
->d_name
.len
;
361 coda_vfs_stat
.unlink
++;
363 error
= venus_remove(dir
->i_sb
, coda_i2f(dir
), name
, len
);
369 coda_dir_changed(dir
, 0);
370 drop_nlink(de
->d_inode
);
376 int coda_rmdir(struct inode
*dir
, struct dentry
*de
)
378 const char *name
= de
->d_name
.name
;
379 int len
= de
->d_name
.len
;
383 coda_vfs_stat
.rmdir
++;
385 if (!d_unhashed(de
)) {
389 error
= venus_rmdir(dir
->i_sb
, coda_i2f(dir
), name
, len
);
396 coda_dir_changed(dir
, -1);
397 drop_nlink(de
->d_inode
);
405 static int coda_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
406 struct inode
*new_dir
, struct dentry
*new_dentry
)
408 const char *old_name
= old_dentry
->d_name
.name
;
409 const char *new_name
= new_dentry
->d_name
.name
;
410 int old_length
= old_dentry
->d_name
.len
;
411 int new_length
= new_dentry
->d_name
.len
;
416 coda_vfs_stat
.rename
++;
418 error
= venus_rename(old_dir
->i_sb
, coda_i2f(old_dir
),
419 coda_i2f(new_dir
), old_length
, new_length
,
420 (const char *) old_name
, (const char *)new_name
);
423 if ( new_dentry
->d_inode
) {
424 if ( S_ISDIR(new_dentry
->d_inode
->i_mode
) )
427 coda_dir_changed(old_dir
, -link_adjust
);
428 coda_dir_changed(new_dir
, link_adjust
);
429 coda_flag_inode(new_dentry
->d_inode
, C_VATTR
);
431 coda_flag_inode(old_dir
, C_VATTR
);
432 coda_flag_inode(new_dir
, C_VATTR
);
441 /* file operations for directories */
442 int coda_readdir(struct file
*coda_file
, void *dirent
, filldir_t filldir
)
444 struct dentry
*coda_dentry
= coda_file
->f_path
.dentry
;
445 struct coda_file_info
*cfi
;
446 struct file
*host_file
;
447 struct inode
*host_inode
;
450 cfi
= CODA_FTOC(coda_file
);
451 BUG_ON(!cfi
|| cfi
->cfi_magic
!= CODA_MAGIC
);
452 host_file
= cfi
->cfi_container
;
454 coda_vfs_stat
.readdir
++;
456 host_inode
= host_file
->f_path
.dentry
->d_inode
;
457 mutex_lock(&host_inode
->i_mutex
);
458 host_file
->f_pos
= coda_file
->f_pos
;
460 if (!host_file
->f_op
->readdir
) {
461 /* Venus: we must read Venus dirents from the file */
462 ret
= coda_venus_readdir(host_file
, filldir
, dirent
, coda_dentry
);
464 /* potemkin case: we were handed a directory inode. */
465 /* Yuk, we can't call vfs_readdir because we are already
466 * holding the inode semaphore. */
468 if (!host_file
->f_op
|| !host_file
->f_op
->readdir
)
472 if (!IS_DEADDIR(host_inode
)) {
473 ret
= host_file
->f_op
->readdir(host_file
, filldir
, dirent
);
474 file_accessed(host_file
);
478 coda_file
->f_pos
= host_file
->f_pos
;
479 mutex_unlock(&host_inode
->i_mutex
);
484 static inline unsigned int CDT2DT(unsigned char cdt
)
489 case CDT_UNKNOWN
: dt
= DT_UNKNOWN
; break;
490 case CDT_FIFO
: dt
= DT_FIFO
; break;
491 case CDT_CHR
: dt
= DT_CHR
; break;
492 case CDT_DIR
: dt
= DT_DIR
; break;
493 case CDT_BLK
: dt
= DT_BLK
; break;
494 case CDT_REG
: dt
= DT_REG
; break;
495 case CDT_LNK
: dt
= DT_LNK
; break;
496 case CDT_SOCK
: dt
= DT_SOCK
; break;
497 case CDT_WHT
: dt
= DT_WHT
; break;
498 default: dt
= DT_UNKNOWN
; break;
503 /* support routines */
504 static int coda_venus_readdir(struct file
*filp
, filldir_t filldir
,
505 void *dirent
, struct dentry
*dir
)
507 int result
= 0; /* # of entries returned */
508 struct venus_dirent
*vdir
;
509 unsigned long vdir_size
=
510 (unsigned long)(&((struct venus_dirent
*)0)->d_name
);
516 vdir
= kmalloc(sizeof(*vdir
), GFP_KERNEL
);
517 if (!vdir
) return -ENOMEM
;
522 ret
= filldir(dirent
, ".", 1, 0, dir
->d_inode
->i_ino
, DT_DIR
);
528 ret
= filldir(dirent
, "..", 2, 1, dir
->d_parent
->d_inode
->i_ino
, DT_DIR
);
535 /* read entries from the directory file */
536 ret
= kernel_read(filp
, filp
->f_pos
- 2, (char *)vdir
,
539 printk("coda_venus_readdir: read dir failed %d\n", ret
);
542 if (ret
== 0) break; /* end of directory file reached */
544 /* catch truncated reads */
545 if (ret
< vdir_size
|| ret
< vdir_size
+ vdir
->d_namlen
) {
546 printk("coda_venus_readdir: short read: %ld\n",
547 filp
->f_path
.dentry
->d_inode
->i_ino
);
551 /* validate whether the directory file actually makes sense */
552 if (vdir
->d_reclen
< vdir_size
+ vdir
->d_namlen
) {
553 printk("coda_venus_readdir: Invalid dir: %ld\n",
554 filp
->f_path
.dentry
->d_inode
->i_ino
);
559 name
.len
= vdir
->d_namlen
;
560 name
.name
= vdir
->d_name
;
562 /* Make sure we skip '.' and '..', we already got those */
563 if (name
.name
[0] == '.' && (name
.len
== 1 ||
564 (vdir
->d_name
[1] == '.' && name
.len
== 2)))
565 vdir
->d_fileno
= name
.len
= 0;
567 /* skip null entries */
568 if (vdir
->d_fileno
&& name
.len
) {
569 /* try to look up this entry in the dcache, that way
570 * userspace doesn't have to worry about breaking
571 * getcwd by having mismatched inode numbers for
572 * internal volume mountpoints. */
573 ino
= find_inode_number(dir
, &name
);
574 if (!ino
) ino
= vdir
->d_fileno
;
576 type
= CDT2DT(vdir
->d_type
);
577 ret
= filldir(dirent
, name
.name
, name
.len
, filp
->f_pos
,
579 /* failure means no space for filling in this round */
583 /* we'll always have progress because d_reclen is unsigned and
584 * we've already established it is non-zero. */
585 filp
->f_pos
+= vdir
->d_reclen
;
589 return result
? result
: ret
;
592 /* called when a cache lookup succeeds */
593 static int coda_dentry_revalidate(struct dentry
*de
, struct nameidata
*nd
)
595 struct inode
*inode
= de
->d_inode
;
596 struct coda_inode_info
*cii
;
601 if (coda_isroot(inode
))
603 if (is_bad_inode(inode
))
606 cii
= ITOC(de
->d_inode
);
607 if (!(cii
->c_flags
& (C_PURGE
| C_FLUSH
)))
610 shrink_dcache_parent(de
);
612 /* propagate for a flush */
613 if (cii
->c_flags
& C_FLUSH
)
614 coda_flag_inode_children(inode
, C_FLUSH
);
616 if (atomic_read(&de
->d_count
) > 1)
617 /* pretend it's valid, but don't change the flags */
620 /* clear the flags. */
621 cii
->c_flags
&= ~(C_VATTR
| C_PURGE
| C_FLUSH
);
632 * This is the callback from dput() when d_count is going to 0.
633 * We use this to unhash dentries with bad inodes.
635 static int coda_dentry_delete(struct dentry
* dentry
)
639 if (!dentry
->d_inode
)
642 flags
= (ITOC(dentry
->d_inode
)->c_flags
) & C_PURGE
;
643 if (is_bad_inode(dentry
->d_inode
) || flags
) {
652 * This is called when we want to check if the inode has
653 * changed on the server. Coda makes this easy since the
654 * cache manager Venus issues a downcall to the kernel when this
657 int coda_revalidate_inode(struct dentry
*dentry
)
659 struct coda_vattr attr
;
663 struct inode
*inode
= dentry
->d_inode
;
664 struct coda_inode_info
*cii
= ITOC(inode
);
670 if (cii
->c_flags
& (C_VATTR
| C_PURGE
| C_FLUSH
)) {
671 error
= venus_getattr(inode
->i_sb
, &(cii
->c_fid
), &attr
);
675 /* this inode may be lost if:
677 - type changes must be permitted for repair and
678 missing mount points.
680 old_mode
= inode
->i_mode
;
681 old_ino
= inode
->i_ino
;
682 coda_vattr_to_iattr(inode
, &attr
);
684 if ((old_mode
& S_IFMT
) != (inode
->i_mode
& S_IFMT
)) {
685 printk("Coda: inode %ld, fid %s changed type!\n",
686 inode
->i_ino
, coda_f2s(&(cii
->c_fid
)));
689 /* the following can happen when a local fid is replaced
690 with a global one, here we lose and declare the inode bad */
691 if (inode
->i_ino
!= old_ino
)
694 coda_flag_inode_children(inode
, C_FLUSH
);
695 cii
->c_flags
&= ~(C_VATTR
| C_PURGE
| C_FLUSH
);