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-rw-r--r--fs/hostfs/hostfs_kern.c517
1 files changed, 229 insertions, 288 deletions
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 87ac1891a185..dd1e55535a4e 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -14,12 +14,12 @@
14#include <linux/slab.h> 14#include <linux/slab.h>
15#include <linux/seq_file.h> 15#include <linux/seq_file.h>
16#include <linux/mount.h> 16#include <linux/mount.h>
17#include <linux/namei.h>
17#include "hostfs.h" 18#include "hostfs.h"
18#include "init.h" 19#include "init.h"
19#include "kern.h" 20#include "kern.h"
20 21
21struct hostfs_inode_info { 22struct hostfs_inode_info {
22 char *host_filename;
23 int fd; 23 int fd;
24 fmode_t mode; 24 fmode_t mode;
25 struct inode vfs_inode; 25 struct inode vfs_inode;
@@ -49,7 +49,7 @@ static int append = 0;
49 49
50static const struct inode_operations hostfs_iops; 50static const struct inode_operations hostfs_iops;
51static const struct inode_operations hostfs_dir_iops; 51static const struct inode_operations hostfs_dir_iops;
52static const struct address_space_operations hostfs_link_aops; 52static const struct inode_operations hostfs_link_iops;
53 53
54#ifndef MODULE 54#ifndef MODULE
55static int __init hostfs_args(char *options, int *add) 55static int __init hostfs_args(char *options, int *add)
@@ -90,71 +90,58 @@ __uml_setup("hostfs=", hostfs_args,
90); 90);
91#endif 91#endif
92 92
93static char *dentry_name(struct dentry *dentry, int extra) 93static char *__dentry_name(struct dentry *dentry, char *name)
94{ 94{
95 struct dentry *parent; 95 char *p = __dentry_path(dentry, name, PATH_MAX);
96 char *root, *name; 96 char *root;
97 int len; 97 size_t len;
98
99 len = 0;
100 parent = dentry;
101 while (parent->d_parent != parent) {
102 len += parent->d_name.len + 1;
103 parent = parent->d_parent;
104 }
105 98
106 root = HOSTFS_I(parent->d_inode)->host_filename; 99 spin_unlock(&dcache_lock);
107 len += strlen(root);
108 name = kmalloc(len + extra + 1, GFP_KERNEL);
109 if (name == NULL)
110 return NULL;
111 100
112 name[len] = '\0'; 101 root = dentry->d_sb->s_fs_info;
113 parent = dentry; 102 len = strlen(root);
114 while (parent->d_parent != parent) { 103 if (IS_ERR(p)) {
115 len -= parent->d_name.len + 1; 104 __putname(name);
116 name[len] = '/'; 105 return NULL;
117 strncpy(&name[len + 1], parent->d_name.name, 106 }
118 parent->d_name.len); 107 strncpy(name, root, PATH_MAX);
119 parent = parent->d_parent; 108 if (len > p - name) {
109 __putname(name);
110 return NULL;
111 }
112 if (p > name + len) {
113 char *s = name + len;
114 while ((*s++ = *p++) != '\0')
115 ;
120 } 116 }
121 strncpy(name, root, strlen(root));
122 return name; 117 return name;
123} 118}
124 119
125static char *inode_name(struct inode *ino, int extra) 120static char *dentry_name(struct dentry *dentry)
126{ 121{
127 struct dentry *dentry; 122 char *name = __getname();
123 if (!name)
124 return NULL;
128 125
129 dentry = list_entry(ino->i_dentry.next, struct dentry, d_alias); 126 spin_lock(&dcache_lock);
130 return dentry_name(dentry, extra); 127 return __dentry_name(dentry, name); /* will unlock */
131} 128}
132 129
133static int read_name(struct inode *ino, char *name) 130static char *inode_name(struct inode *ino)
134{ 131{
135 /* 132 struct dentry *dentry;
136 * The non-int inode fields are copied into ints by stat_file and 133 char *name = __getname();
137 * then copied into the inode because passing the actual pointers 134 if (!name)
138 * in and having them treated as int * breaks on big-endian machines 135 return NULL;
139 */
140 int err;
141 int i_mode, i_nlink, i_blksize;
142 unsigned long long i_size;
143 unsigned long long i_ino;
144 unsigned long long i_blocks;
145
146 err = stat_file(name, &i_ino, &i_mode, &i_nlink, &ino->i_uid,
147 &ino->i_gid, &i_size, &ino->i_atime, &ino->i_mtime,
148 &ino->i_ctime, &i_blksize, &i_blocks, -1);
149 if (err)
150 return err;
151 136
152 ino->i_ino = i_ino; 137 spin_lock(&dcache_lock);
153 ino->i_mode = i_mode; 138 if (list_empty(&ino->i_dentry)) {
154 ino->i_nlink = i_nlink; 139 spin_unlock(&dcache_lock);
155 ino->i_size = i_size; 140 __putname(name);
156 ino->i_blocks = i_blocks; 141 return NULL;
157 return 0; 142 }
143 dentry = list_first_entry(&ino->i_dentry, struct dentry, d_alias);
144 return __dentry_name(dentry, name); /* will unlock */
158} 145}
159 146
160static char *follow_link(char *link) 147static char *follow_link(char *link)
@@ -205,53 +192,11 @@ static char *follow_link(char *link)
205 return ERR_PTR(n); 192 return ERR_PTR(n);
206} 193}
207 194
208static int hostfs_read_inode(struct inode *ino)
209{
210 char *name;
211 int err = 0;
212
213 /*
214 * Unfortunately, we are called from iget() when we don't have a dentry
215 * allocated yet.
216 */
217 if (list_empty(&ino->i_dentry))
218 goto out;
219
220 err = -ENOMEM;
221 name = inode_name(ino, 0);
222 if (name == NULL)
223 goto out;
224
225 if (file_type(name, NULL, NULL) == OS_TYPE_SYMLINK) {
226 name = follow_link(name);
227 if (IS_ERR(name)) {
228 err = PTR_ERR(name);
229 goto out;
230 }
231 }
232
233 err = read_name(ino, name);
234 kfree(name);
235 out:
236 return err;
237}
238
239static struct inode *hostfs_iget(struct super_block *sb) 195static struct inode *hostfs_iget(struct super_block *sb)
240{ 196{
241 struct inode *inode; 197 struct inode *inode = new_inode(sb);
242 long ret;
243
244 inode = iget_locked(sb, 0);
245 if (!inode) 198 if (!inode)
246 return ERR_PTR(-ENOMEM); 199 return ERR_PTR(-ENOMEM);
247 if (inode->i_state & I_NEW) {
248 ret = hostfs_read_inode(inode);
249 if (ret < 0) {
250 iget_failed(inode);
251 return ERR_PTR(ret);
252 }
253 unlock_new_inode(inode);
254 }
255 return inode; 200 return inode;
256} 201}
257 202
@@ -269,7 +214,7 @@ int hostfs_statfs(struct dentry *dentry, struct kstatfs *sf)
269 long long f_files; 214 long long f_files;
270 long long f_ffree; 215 long long f_ffree;
271 216
272 err = do_statfs(HOSTFS_I(dentry->d_sb->s_root->d_inode)->host_filename, 217 err = do_statfs(dentry->d_sb->s_fs_info,
273 &sf->f_bsize, &f_blocks, &f_bfree, &f_bavail, &f_files, 218 &sf->f_bsize, &f_blocks, &f_bfree, &f_bavail, &f_files,
274 &f_ffree, &sf->f_fsid, sizeof(sf->f_fsid), 219 &f_ffree, &sf->f_fsid, sizeof(sf->f_fsid),
275 &sf->f_namelen, sf->f_spare); 220 &sf->f_namelen, sf->f_spare);
@@ -288,47 +233,32 @@ static struct inode *hostfs_alloc_inode(struct super_block *sb)
288{ 233{
289 struct hostfs_inode_info *hi; 234 struct hostfs_inode_info *hi;
290 235
291 hi = kmalloc(sizeof(*hi), GFP_KERNEL); 236 hi = kzalloc(sizeof(*hi), GFP_KERNEL);
292 if (hi == NULL) 237 if (hi == NULL)
293 return NULL; 238 return NULL;
294 239 hi->fd = -1;
295 *hi = ((struct hostfs_inode_info) { .host_filename = NULL,
296 .fd = -1,
297 .mode = 0 });
298 inode_init_once(&hi->vfs_inode); 240 inode_init_once(&hi->vfs_inode);
299 return &hi->vfs_inode; 241 return &hi->vfs_inode;
300} 242}
301 243
302static void hostfs_delete_inode(struct inode *inode) 244static void hostfs_evict_inode(struct inode *inode)
303{ 245{
304 truncate_inode_pages(&inode->i_data, 0); 246 truncate_inode_pages(&inode->i_data, 0);
247 end_writeback(inode);
305 if (HOSTFS_I(inode)->fd != -1) { 248 if (HOSTFS_I(inode)->fd != -1) {
306 close_file(&HOSTFS_I(inode)->fd); 249 close_file(&HOSTFS_I(inode)->fd);
307 HOSTFS_I(inode)->fd = -1; 250 HOSTFS_I(inode)->fd = -1;
308 } 251 }
309 clear_inode(inode);
310} 252}
311 253
312static void hostfs_destroy_inode(struct inode *inode) 254static void hostfs_destroy_inode(struct inode *inode)
313{ 255{
314 kfree(HOSTFS_I(inode)->host_filename);
315
316 /*
317 * XXX: This should not happen, probably. The check is here for
318 * additional safety.
319 */
320 if (HOSTFS_I(inode)->fd != -1) {
321 close_file(&HOSTFS_I(inode)->fd);
322 printk(KERN_DEBUG "Closing host fd in .destroy_inode\n");
323 }
324
325 kfree(HOSTFS_I(inode)); 256 kfree(HOSTFS_I(inode));
326} 257}
327 258
328static int hostfs_show_options(struct seq_file *seq, struct vfsmount *vfs) 259static int hostfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
329{ 260{
330 struct inode *root = vfs->mnt_sb->s_root->d_inode; 261 const char *root_path = vfs->mnt_sb->s_fs_info;
331 const char *root_path = HOSTFS_I(root)->host_filename;
332 size_t offset = strlen(root_ino) + 1; 262 size_t offset = strlen(root_ino) + 1;
333 263
334 if (strlen(root_path) > offset) 264 if (strlen(root_path) > offset)
@@ -339,9 +269,8 @@ static int hostfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
339 269
340static const struct super_operations hostfs_sbops = { 270static const struct super_operations hostfs_sbops = {
341 .alloc_inode = hostfs_alloc_inode, 271 .alloc_inode = hostfs_alloc_inode,
342 .drop_inode = generic_delete_inode,
343 .delete_inode = hostfs_delete_inode,
344 .destroy_inode = hostfs_destroy_inode, 272 .destroy_inode = hostfs_destroy_inode,
273 .evict_inode = hostfs_evict_inode,
345 .statfs = hostfs_statfs, 274 .statfs = hostfs_statfs,
346 .show_options = hostfs_show_options, 275 .show_options = hostfs_show_options,
347}; 276};
@@ -353,11 +282,11 @@ int hostfs_readdir(struct file *file, void *ent, filldir_t filldir)
353 unsigned long long next, ino; 282 unsigned long long next, ino;
354 int error, len; 283 int error, len;
355 284
356 name = dentry_name(file->f_path.dentry, 0); 285 name = dentry_name(file->f_path.dentry);
357 if (name == NULL) 286 if (name == NULL)
358 return -ENOMEM; 287 return -ENOMEM;
359 dir = open_dir(name, &error); 288 dir = open_dir(name, &error);
360 kfree(name); 289 __putname(name);
361 if (dir == NULL) 290 if (dir == NULL)
362 return -error; 291 return -error;
363 next = file->f_pos; 292 next = file->f_pos;
@@ -373,40 +302,59 @@ int hostfs_readdir(struct file *file, void *ent, filldir_t filldir)
373 302
374int hostfs_file_open(struct inode *ino, struct file *file) 303int hostfs_file_open(struct inode *ino, struct file *file)
375{ 304{
305 static DEFINE_MUTEX(open_mutex);
376 char *name; 306 char *name;
377 fmode_t mode = 0; 307 fmode_t mode = 0;
308 int err;
378 int r = 0, w = 0, fd; 309 int r = 0, w = 0, fd;
379 310
380 mode = file->f_mode & (FMODE_READ | FMODE_WRITE); 311 mode = file->f_mode & (FMODE_READ | FMODE_WRITE);
381 if ((mode & HOSTFS_I(ino)->mode) == mode) 312 if ((mode & HOSTFS_I(ino)->mode) == mode)
382 return 0; 313 return 0;
383 314
384 /* 315 mode |= HOSTFS_I(ino)->mode;
385 * The file may already have been opened, but with the wrong access,
386 * so this resets things and reopens the file with the new access.
387 */
388 if (HOSTFS_I(ino)->fd != -1) {
389 close_file(&HOSTFS_I(ino)->fd);
390 HOSTFS_I(ino)->fd = -1;
391 }
392 316
393 HOSTFS_I(ino)->mode |= mode; 317retry:
394 if (HOSTFS_I(ino)->mode & FMODE_READ) 318 if (mode & FMODE_READ)
395 r = 1; 319 r = 1;
396 if (HOSTFS_I(ino)->mode & FMODE_WRITE) 320 if (mode & FMODE_WRITE)
397 w = 1; 321 w = 1;
398 if (w) 322 if (w)
399 r = 1; 323 r = 1;
400 324
401 name = dentry_name(file->f_path.dentry, 0); 325 name = dentry_name(file->f_path.dentry);
402 if (name == NULL) 326 if (name == NULL)
403 return -ENOMEM; 327 return -ENOMEM;
404 328
405 fd = open_file(name, r, w, append); 329 fd = open_file(name, r, w, append);
406 kfree(name); 330 __putname(name);
407 if (fd < 0) 331 if (fd < 0)
408 return fd; 332 return fd;
409 FILE_HOSTFS_I(file)->fd = fd; 333
334 mutex_lock(&open_mutex);
335 /* somebody else had handled it first? */
336 if ((mode & HOSTFS_I(ino)->mode) == mode) {
337 mutex_unlock(&open_mutex);
338 return 0;
339 }
340 if ((mode | HOSTFS_I(ino)->mode) != mode) {
341 mode |= HOSTFS_I(ino)->mode;
342 mutex_unlock(&open_mutex);
343 close_file(&fd);
344 goto retry;
345 }
346 if (HOSTFS_I(ino)->fd == -1) {
347 HOSTFS_I(ino)->fd = fd;
348 } else {
349 err = replace_file(fd, HOSTFS_I(ino)->fd);
350 close_file(&fd);
351 if (err < 0) {
352 mutex_unlock(&open_mutex);
353 return err;
354 }
355 }
356 HOSTFS_I(ino)->mode = mode;
357 mutex_unlock(&open_mutex);
410 358
411 return 0; 359 return 0;
412} 360}
@@ -544,54 +492,50 @@ static const struct address_space_operations hostfs_aops = {
544 .write_end = hostfs_write_end, 492 .write_end = hostfs_write_end,
545}; 493};
546 494
547static int init_inode(struct inode *inode, struct dentry *dentry) 495static int read_name(struct inode *ino, char *name)
548{ 496{
549 char *name; 497 dev_t rdev;
550 int type, err = -ENOMEM; 498 struct hostfs_stat st;
551 int maj, min; 499 int err = stat_file(name, &st, -1);
552 dev_t rdev = 0; 500 if (err)
501 return err;
553 502
554 if (dentry) { 503 /* Reencode maj and min with the kernel encoding.*/
555 name = dentry_name(dentry, 0); 504 rdev = MKDEV(st.maj, st.min);
556 if (name == NULL)
557 goto out;
558 type = file_type(name, &maj, &min);
559 /* Reencode maj and min with the kernel encoding.*/
560 rdev = MKDEV(maj, min);
561 kfree(name);
562 }
563 else type = OS_TYPE_DIR;
564 505
565 err = 0; 506 switch (st.mode & S_IFMT) {
566 if (type == OS_TYPE_SYMLINK) 507 case S_IFLNK:
567 inode->i_op = &page_symlink_inode_operations; 508 ino->i_op = &hostfs_link_iops;
568 else if (type == OS_TYPE_DIR)
569 inode->i_op = &hostfs_dir_iops;
570 else inode->i_op = &hostfs_iops;
571
572 if (type == OS_TYPE_DIR) inode->i_fop = &hostfs_dir_fops;
573 else inode->i_fop = &hostfs_file_fops;
574
575 if (type == OS_TYPE_SYMLINK)
576 inode->i_mapping->a_ops = &hostfs_link_aops;
577 else inode->i_mapping->a_ops = &hostfs_aops;
578
579 switch (type) {
580 case OS_TYPE_CHARDEV:
581 init_special_inode(inode, S_IFCHR, rdev);
582 break; 509 break;
583 case OS_TYPE_BLOCKDEV: 510 case S_IFDIR:
584 init_special_inode(inode, S_IFBLK, rdev); 511 ino->i_op = &hostfs_dir_iops;
512 ino->i_fop = &hostfs_dir_fops;
585 break; 513 break;
586 case OS_TYPE_FIFO: 514 case S_IFCHR:
587 init_special_inode(inode, S_IFIFO, 0); 515 case S_IFBLK:
516 case S_IFIFO:
517 case S_IFSOCK:
518 init_special_inode(ino, st.mode & S_IFMT, rdev);
519 ino->i_op = &hostfs_iops;
588 break; 520 break;
589 case OS_TYPE_SOCK: 521
590 init_special_inode(inode, S_IFSOCK, 0); 522 default:
591 break; 523 ino->i_op = &hostfs_iops;
592 } 524 ino->i_fop = &hostfs_file_fops;
593 out: 525 ino->i_mapping->a_ops = &hostfs_aops;
594 return err; 526 }
527
528 ino->i_ino = st.ino;
529 ino->i_mode = st.mode;
530 ino->i_nlink = st.nlink;
531 ino->i_uid = st.uid;
532 ino->i_gid = st.gid;
533 ino->i_atime = st.atime;
534 ino->i_mtime = st.mtime;
535 ino->i_ctime = st.ctime;
536 ino->i_size = st.size;
537 ino->i_blocks = st.blocks;
538 return 0;
595} 539}
596 540
597int hostfs_create(struct inode *dir, struct dentry *dentry, int mode, 541int hostfs_create(struct inode *dir, struct dentry *dentry, int mode,
@@ -607,12 +551,8 @@ int hostfs_create(struct inode *dir, struct dentry *dentry, int mode,
607 goto out; 551 goto out;
608 } 552 }
609 553
610 error = init_inode(inode, dentry);
611 if (error)
612 goto out_put;
613
614 error = -ENOMEM; 554 error = -ENOMEM;
615 name = dentry_name(dentry, 0); 555 name = dentry_name(dentry);
616 if (name == NULL) 556 if (name == NULL)
617 goto out_put; 557 goto out_put;
618 558
@@ -622,9 +562,10 @@ int hostfs_create(struct inode *dir, struct dentry *dentry, int mode,
622 mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH); 562 mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH);
623 if (fd < 0) 563 if (fd < 0)
624 error = fd; 564 error = fd;
625 else error = read_name(inode, name); 565 else
566 error = read_name(inode, name);
626 567
627 kfree(name); 568 __putname(name);
628 if (error) 569 if (error)
629 goto out_put; 570 goto out_put;
630 571
@@ -652,17 +593,14 @@ struct dentry *hostfs_lookup(struct inode *ino, struct dentry *dentry,
652 goto out; 593 goto out;
653 } 594 }
654 595
655 err = init_inode(inode, dentry);
656 if (err)
657 goto out_put;
658
659 err = -ENOMEM; 596 err = -ENOMEM;
660 name = dentry_name(dentry, 0); 597 name = dentry_name(dentry);
661 if (name == NULL) 598 if (name == NULL)
662 goto out_put; 599 goto out_put;
663 600
664 err = read_name(inode, name); 601 err = read_name(inode, name);
665 kfree(name); 602
603 __putname(name);
666 if (err == -ENOENT) { 604 if (err == -ENOENT) {
667 iput(inode); 605 iput(inode);
668 inode = NULL; 606 inode = NULL;
@@ -680,36 +618,21 @@ struct dentry *hostfs_lookup(struct inode *ino, struct dentry *dentry,
680 return ERR_PTR(err); 618 return ERR_PTR(err);
681} 619}
682 620
683static char *inode_dentry_name(struct inode *ino, struct dentry *dentry)
684{
685 char *file;
686 int len;
687
688 file = inode_name(ino, dentry->d_name.len + 1);
689 if (file == NULL)
690 return NULL;
691 strcat(file, "/");
692 len = strlen(file);
693 strncat(file, dentry->d_name.name, dentry->d_name.len);
694 file[len + dentry->d_name.len] = '\0';
695 return file;
696}
697
698int hostfs_link(struct dentry *to, struct inode *ino, struct dentry *from) 621int hostfs_link(struct dentry *to, struct inode *ino, struct dentry *from)
699{ 622{
700 char *from_name, *to_name; 623 char *from_name, *to_name;
701 int err; 624 int err;
702 625
703 if ((from_name = inode_dentry_name(ino, from)) == NULL) 626 if ((from_name = dentry_name(from)) == NULL)
704 return -ENOMEM; 627 return -ENOMEM;
705 to_name = dentry_name(to, 0); 628 to_name = dentry_name(to);
706 if (to_name == NULL) { 629 if (to_name == NULL) {
707 kfree(from_name); 630 __putname(from_name);
708 return -ENOMEM; 631 return -ENOMEM;
709 } 632 }
710 err = link_file(to_name, from_name); 633 err = link_file(to_name, from_name);
711 kfree(from_name); 634 __putname(from_name);
712 kfree(to_name); 635 __putname(to_name);
713 return err; 636 return err;
714} 637}
715 638
@@ -718,13 +641,14 @@ int hostfs_unlink(struct inode *ino, struct dentry *dentry)
718 char *file; 641 char *file;
719 int err; 642 int err;
720 643
721 if ((file = inode_dentry_name(ino, dentry)) == NULL)
722 return -ENOMEM;
723 if (append) 644 if (append)
724 return -EPERM; 645 return -EPERM;
725 646
647 if ((file = dentry_name(dentry)) == NULL)
648 return -ENOMEM;
649
726 err = unlink_file(file); 650 err = unlink_file(file);
727 kfree(file); 651 __putname(file);
728 return err; 652 return err;
729} 653}
730 654
@@ -733,10 +657,10 @@ int hostfs_symlink(struct inode *ino, struct dentry *dentry, const char *to)
733 char *file; 657 char *file;
734 int err; 658 int err;
735 659
736 if ((file = inode_dentry_name(ino, dentry)) == NULL) 660 if ((file = dentry_name(dentry)) == NULL)
737 return -ENOMEM; 661 return -ENOMEM;
738 err = make_symlink(file, to); 662 err = make_symlink(file, to);
739 kfree(file); 663 __putname(file);
740 return err; 664 return err;
741} 665}
742 666
@@ -745,10 +669,10 @@ int hostfs_mkdir(struct inode *ino, struct dentry *dentry, int mode)
745 char *file; 669 char *file;
746 int err; 670 int err;
747 671
748 if ((file = inode_dentry_name(ino, dentry)) == NULL) 672 if ((file = dentry_name(dentry)) == NULL)
749 return -ENOMEM; 673 return -ENOMEM;
750 err = do_mkdir(file, mode); 674 err = do_mkdir(file, mode);
751 kfree(file); 675 __putname(file);
752 return err; 676 return err;
753} 677}
754 678
@@ -757,10 +681,10 @@ int hostfs_rmdir(struct inode *ino, struct dentry *dentry)
757 char *file; 681 char *file;
758 int err; 682 int err;
759 683
760 if ((file = inode_dentry_name(ino, dentry)) == NULL) 684 if ((file = dentry_name(dentry)) == NULL)
761 return -ENOMEM; 685 return -ENOMEM;
762 err = do_rmdir(file); 686 err = do_rmdir(file);
763 kfree(file); 687 __putname(file);
764 return err; 688 return err;
765} 689}
766 690
@@ -776,22 +700,20 @@ int hostfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
776 goto out; 700 goto out;
777 } 701 }
778 702
779 err = init_inode(inode, dentry);
780 if (err)
781 goto out_put;
782
783 err = -ENOMEM; 703 err = -ENOMEM;
784 name = dentry_name(dentry, 0); 704 name = dentry_name(dentry);
785 if (name == NULL) 705 if (name == NULL)
786 goto out_put; 706 goto out_put;
787 707
788 init_special_inode(inode, mode, dev); 708 init_special_inode(inode, mode, dev);
789 err = do_mknod(name, mode, MAJOR(dev), MINOR(dev)); 709 err = do_mknod(name, mode, MAJOR(dev), MINOR(dev));
790 if (err) 710 if (!err)
791 goto out_free; 711 goto out_free;
792 712
793 err = read_name(inode, name); 713 err = read_name(inode, name);
794 kfree(name); 714 __putname(name);
715 if (err)
716 goto out_put;
795 if (err) 717 if (err)
796 goto out_put; 718 goto out_put;
797 719
@@ -799,7 +721,7 @@ int hostfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
799 return 0; 721 return 0;
800 722
801 out_free: 723 out_free:
802 kfree(name); 724 __putname(name);
803 out_put: 725 out_put:
804 iput(inode); 726 iput(inode);
805 out: 727 out:
@@ -812,15 +734,15 @@ int hostfs_rename(struct inode *from_ino, struct dentry *from,
812 char *from_name, *to_name; 734 char *from_name, *to_name;
813 int err; 735 int err;
814 736
815 if ((from_name = inode_dentry_name(from_ino, from)) == NULL) 737 if ((from_name = dentry_name(from)) == NULL)
816 return -ENOMEM; 738 return -ENOMEM;
817 if ((to_name = inode_dentry_name(to_ino, to)) == NULL) { 739 if ((to_name = dentry_name(to)) == NULL) {
818 kfree(from_name); 740 __putname(from_name);
819 return -ENOMEM; 741 return -ENOMEM;
820 } 742 }
821 err = rename_file(from_name, to_name); 743 err = rename_file(from_name, to_name);
822 kfree(from_name); 744 __putname(from_name);
823 kfree(to_name); 745 __putname(to_name);
824 return err; 746 return err;
825} 747}
826 748
@@ -832,7 +754,7 @@ int hostfs_permission(struct inode *ino, int desired)
832 if (desired & MAY_READ) r = 1; 754 if (desired & MAY_READ) r = 1;
833 if (desired & MAY_WRITE) w = 1; 755 if (desired & MAY_WRITE) w = 1;
834 if (desired & MAY_EXEC) x = 1; 756 if (desired & MAY_EXEC) x = 1;
835 name = inode_name(ino, 0); 757 name = inode_name(ino);
836 if (name == NULL) 758 if (name == NULL)
837 return -ENOMEM; 759 return -ENOMEM;
838 760
@@ -841,7 +763,7 @@ int hostfs_permission(struct inode *ino, int desired)
841 err = 0; 763 err = 0;
842 else 764 else
843 err = access_file(name, r, w, x); 765 err = access_file(name, r, w, x);
844 kfree(name); 766 __putname(name);
845 if (!err) 767 if (!err)
846 err = generic_permission(ino, desired, NULL); 768 err = generic_permission(ino, desired, NULL);
847 return err; 769 return err;
@@ -849,13 +771,14 @@ int hostfs_permission(struct inode *ino, int desired)
849 771
850int hostfs_setattr(struct dentry *dentry, struct iattr *attr) 772int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
851{ 773{
774 struct inode *inode = dentry->d_inode;
852 struct hostfs_iattr attrs; 775 struct hostfs_iattr attrs;
853 char *name; 776 char *name;
854 int err; 777 int err;
855 778
856 int fd = HOSTFS_I(dentry->d_inode)->fd; 779 int fd = HOSTFS_I(inode)->fd;
857 780
858 err = inode_change_ok(dentry->d_inode, attr); 781 err = inode_change_ok(inode, attr);
859 if (err) 782 if (err)
860 return err; 783 return err;
861 784
@@ -897,15 +820,26 @@ int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
897 if (attr->ia_valid & ATTR_MTIME_SET) { 820 if (attr->ia_valid & ATTR_MTIME_SET) {
898 attrs.ia_valid |= HOSTFS_ATTR_MTIME_SET; 821 attrs.ia_valid |= HOSTFS_ATTR_MTIME_SET;
899 } 822 }
900 name = dentry_name(dentry, 0); 823 name = dentry_name(dentry);
901 if (name == NULL) 824 if (name == NULL)
902 return -ENOMEM; 825 return -ENOMEM;
903 err = set_attr(name, &attrs, fd); 826 err = set_attr(name, &attrs, fd);
904 kfree(name); 827 __putname(name);
905 if (err) 828 if (err)
906 return err; 829 return err;
907 830
908 return inode_setattr(dentry->d_inode, attr); 831 if ((attr->ia_valid & ATTR_SIZE) &&
832 attr->ia_size != i_size_read(inode)) {
833 int error;
834
835 error = vmtruncate(inode, attr->ia_size);
836 if (err)
837 return err;
838 }
839
840 setattr_copy(inode, attr);
841 mark_inode_dirty(inode);
842 return 0;
909} 843}
910 844
911static const struct inode_operations hostfs_iops = { 845static const struct inode_operations hostfs_iops = {
@@ -935,32 +869,41 @@ static const struct inode_operations hostfs_dir_iops = {
935 .setattr = hostfs_setattr, 869 .setattr = hostfs_setattr,
936}; 870};
937 871
938int hostfs_link_readpage(struct file *file, struct page *page) 872static void *hostfs_follow_link(struct dentry *dentry, struct nameidata *nd)
939{ 873{
940 char *buffer, *name; 874 char *link = __getname();
941 int err; 875 if (link) {
942 876 char *path = dentry_name(dentry);
943 buffer = kmap(page); 877 int err = -ENOMEM;
944 name = inode_name(page->mapping->host, 0); 878 if (path) {
945 if (name == NULL) 879 int err = hostfs_do_readlink(path, link, PATH_MAX);
946 return -ENOMEM; 880 if (err == PATH_MAX)
947 err = hostfs_do_readlink(name, buffer, PAGE_CACHE_SIZE); 881 err = -E2BIG;
948 kfree(name); 882 __putname(path);
949 if (err == PAGE_CACHE_SIZE) 883 }
950 err = -E2BIG; 884 if (err < 0) {
951 else if (err > 0) { 885 __putname(link);
952 flush_dcache_page(page); 886 link = ERR_PTR(err);
953 SetPageUptodate(page); 887 }
954 if (PageError(page)) ClearPageError(page); 888 } else {
955 err = 0; 889 link = ERR_PTR(-ENOMEM);
956 } 890 }
957 kunmap(page); 891
958 unlock_page(page); 892 nd_set_link(nd, link);
959 return err; 893 return NULL;
960} 894}
961 895
962static const struct address_space_operations hostfs_link_aops = { 896static void hostfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
963 .readpage = hostfs_link_readpage, 897{
898 char *s = nd_get_link(nd);
899 if (!IS_ERR(s))
900 __putname(s);
901}
902
903static const struct inode_operations hostfs_link_iops = {
904 .readlink = generic_readlink,
905 .follow_link = hostfs_follow_link,
906 .put_link = hostfs_put_link,
964}; 907};
965 908
966static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent) 909static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent)
@@ -980,49 +923,41 @@ static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent)
980 req_root = ""; 923 req_root = "";
981 924
982 err = -ENOMEM; 925 err = -ENOMEM;
983 host_root_path = kmalloc(strlen(root_ino) + 1 926 sb->s_fs_info = host_root_path =
984 + strlen(req_root) + 1, GFP_KERNEL); 927 kmalloc(strlen(root_ino) + strlen(req_root) + 2, GFP_KERNEL);
985 if (host_root_path == NULL) 928 if (host_root_path == NULL)
986 goto out; 929 goto out;
987 930
988 sprintf(host_root_path, "%s/%s", root_ino, req_root); 931 sprintf(host_root_path, "%s/%s", root_ino, req_root);
989 932
990 root_inode = hostfs_iget(sb); 933 root_inode = new_inode(sb);
991 if (IS_ERR(root_inode)) { 934 if (!root_inode)
992 err = PTR_ERR(root_inode); 935 goto out;
993 goto out_free;
994 }
995 936
996 err = init_inode(root_inode, NULL); 937 err = read_name(root_inode, host_root_path);
997 if (err) 938 if (err)
998 goto out_put; 939 goto out_put;
999 940
1000 HOSTFS_I(root_inode)->host_filename = host_root_path; 941 if (S_ISLNK(root_inode->i_mode)) {
1001 /* 942 char *name = follow_link(host_root_path);
1002 * Avoid that in the error path, iput(root_inode) frees again 943 if (IS_ERR(name))
1003 * host_root_path through hostfs_destroy_inode! 944 err = PTR_ERR(name);
1004 */ 945 else
1005 host_root_path = NULL; 946 err = read_name(root_inode, name);
947 kfree(name);
948 if (err)
949 goto out_put;
950 }
1006 951
1007 err = -ENOMEM; 952 err = -ENOMEM;
1008 sb->s_root = d_alloc_root(root_inode); 953 sb->s_root = d_alloc_root(root_inode);
1009 if (sb->s_root == NULL) 954 if (sb->s_root == NULL)
1010 goto out_put; 955 goto out_put;
1011 956
1012 err = hostfs_read_inode(root_inode);
1013 if (err) {
1014 /* No iput in this case because the dput does that for us */
1015 dput(sb->s_root);
1016 sb->s_root = NULL;
1017 goto out;
1018 }
1019
1020 return 0; 957 return 0;
1021 958
1022out_put: 959out_put:
1023 iput(root_inode); 960 iput(root_inode);
1024out_free:
1025 kfree(host_root_path);
1026out: 961out:
1027 return err; 962 return err;
1028} 963}
@@ -1034,11 +969,17 @@ static int hostfs_read_sb(struct file_system_type *type,
1034 return get_sb_nodev(type, flags, data, hostfs_fill_sb_common, mnt); 969 return get_sb_nodev(type, flags, data, hostfs_fill_sb_common, mnt);
1035} 970}
1036 971
972static void hostfs_kill_sb(struct super_block *s)
973{
974 kill_anon_super(s);
975 kfree(s->s_fs_info);
976}
977
1037static struct file_system_type hostfs_type = { 978static struct file_system_type hostfs_type = {
1038 .owner = THIS_MODULE, 979 .owner = THIS_MODULE,
1039 .name = "hostfs", 980 .name = "hostfs",
1040 .get_sb = hostfs_read_sb, 981 .get_sb = hostfs_read_sb,
1041 .kill_sb = kill_anon_super, 982 .kill_sb = hostfs_kill_sb,
1042 .fs_flags = 0, 983 .fs_flags = 0,
1043}; 984};
1044 985