ia64/linux-2.6.18-xen.hg

view fs/affs/amigaffs.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /*
2 * linux/fs/affs/amigaffs.c
3 *
4 * (c) 1996 Hans-Joachim Widmaier - Rewritten
5 *
6 * (C) 1993 Ray Burr - Amiga FFS filesystem.
7 *
8 * Please send bug reports to: hjw@zvw.de
9 */
11 #include "affs.h"
13 extern struct timezone sys_tz;
15 static char ErrorBuffer[256];
17 /*
18 * Functions for accessing Amiga-FFS structures.
19 */
22 /* Insert a header block bh into the directory dir
23 * caller must hold AFFS_DIR->i_hash_lock!
24 */
26 int
27 affs_insert_hash(struct inode *dir, struct buffer_head *bh)
28 {
29 struct super_block *sb = dir->i_sb;
30 struct buffer_head *dir_bh;
31 u32 ino, hash_ino;
32 int offset;
34 ino = bh->b_blocknr;
35 offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
37 pr_debug("AFFS: insert_hash(dir=%u, ino=%d)\n", (u32)dir->i_ino, ino);
39 dir_bh = affs_bread(sb, dir->i_ino);
40 if (!dir_bh)
41 return -EIO;
43 hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
44 while (hash_ino) {
45 affs_brelse(dir_bh);
46 dir_bh = affs_bread(sb, hash_ino);
47 if (!dir_bh)
48 return -EIO;
49 hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
50 }
51 AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
52 AFFS_TAIL(sb, bh)->hash_chain = 0;
53 affs_fix_checksum(sb, bh);
55 if (dir->i_ino == dir_bh->b_blocknr)
56 AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
57 else
58 AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
60 affs_adjust_checksum(dir_bh, ino);
61 mark_buffer_dirty_inode(dir_bh, dir);
62 affs_brelse(dir_bh);
64 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
65 dir->i_version++;
66 mark_inode_dirty(dir);
68 return 0;
69 }
71 /* Remove a header block from its directory.
72 * caller must hold AFFS_DIR->i_hash_lock!
73 */
75 int
76 affs_remove_hash(struct inode *dir, struct buffer_head *rem_bh)
77 {
78 struct super_block *sb;
79 struct buffer_head *bh;
80 u32 rem_ino, hash_ino;
81 __be32 ino;
82 int offset, retval;
84 sb = dir->i_sb;
85 rem_ino = rem_bh->b_blocknr;
86 offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
87 pr_debug("AFFS: remove_hash(dir=%d, ino=%d, hashval=%d)\n", (u32)dir->i_ino, rem_ino, offset);
89 bh = affs_bread(sb, dir->i_ino);
90 if (!bh)
91 return -EIO;
93 retval = -ENOENT;
94 hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
95 while (hash_ino) {
96 if (hash_ino == rem_ino) {
97 ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
98 if (dir->i_ino == bh->b_blocknr)
99 AFFS_HEAD(bh)->table[offset] = ino;
100 else
101 AFFS_TAIL(sb, bh)->hash_chain = ino;
102 affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
103 mark_buffer_dirty_inode(bh, dir);
104 AFFS_TAIL(sb, rem_bh)->parent = 0;
105 retval = 0;
106 break;
107 }
108 affs_brelse(bh);
109 bh = affs_bread(sb, hash_ino);
110 if (!bh)
111 return -EIO;
112 hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
113 }
115 affs_brelse(bh);
117 dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
118 dir->i_version++;
119 mark_inode_dirty(dir);
121 return retval;
122 }
124 static void
125 affs_fix_dcache(struct dentry *dentry, u32 entry_ino)
126 {
127 struct inode *inode = dentry->d_inode;
128 void *data = dentry->d_fsdata;
129 struct list_head *head, *next;
131 spin_lock(&dcache_lock);
132 head = &inode->i_dentry;
133 next = head->next;
134 while (next != head) {
135 dentry = list_entry(next, struct dentry, d_alias);
136 if (entry_ino == (u32)(long)dentry->d_fsdata) {
137 dentry->d_fsdata = data;
138 break;
139 }
140 next = next->next;
141 }
142 spin_unlock(&dcache_lock);
143 }
146 /* Remove header from link chain */
148 static int
149 affs_remove_link(struct dentry *dentry)
150 {
151 struct inode *dir, *inode = dentry->d_inode;
152 struct super_block *sb = inode->i_sb;
153 struct buffer_head *bh = NULL, *link_bh = NULL;
154 u32 link_ino, ino;
155 int retval;
157 pr_debug("AFFS: remove_link(key=%ld)\n", inode->i_ino);
158 retval = -EIO;
159 bh = affs_bread(sb, inode->i_ino);
160 if (!bh)
161 goto done;
163 link_ino = (u32)(long)dentry->d_fsdata;
164 if (inode->i_ino == link_ino) {
165 /* we can't remove the head of the link, as its blocknr is still used as ino,
166 * so we remove the block of the first link instead.
167 */
168 link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
169 link_bh = affs_bread(sb, link_ino);
170 if (!link_bh)
171 goto done;
173 dir = iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
174 if (!dir)
175 goto done;
177 affs_lock_dir(dir);
178 affs_fix_dcache(dentry, link_ino);
179 retval = affs_remove_hash(dir, link_bh);
180 if (retval)
181 goto done;
182 mark_buffer_dirty_inode(link_bh, inode);
184 memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
185 retval = affs_insert_hash(dir, bh);
186 if (retval)
187 goto done;
188 mark_buffer_dirty_inode(bh, inode);
190 affs_unlock_dir(dir);
191 iput(dir);
192 } else {
193 link_bh = affs_bread(sb, link_ino);
194 if (!link_bh)
195 goto done;
196 }
198 while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
199 if (ino == link_ino) {
200 __be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
201 AFFS_TAIL(sb, bh)->link_chain = ino2;
202 affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
203 mark_buffer_dirty_inode(bh, inode);
204 retval = 0;
205 /* Fix the link count, if bh is a normal header block without links */
206 switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
207 case ST_LINKDIR:
208 case ST_LINKFILE:
209 break;
210 default:
211 if (!AFFS_TAIL(sb, bh)->link_chain)
212 inode->i_nlink = 1;
213 }
214 affs_free_block(sb, link_ino);
215 goto done;
216 }
217 affs_brelse(bh);
218 bh = affs_bread(sb, ino);
219 if (!bh)
220 goto done;
221 }
222 retval = -ENOENT;
223 done:
224 affs_brelse(link_bh);
225 affs_brelse(bh);
226 return retval;
227 }
230 static int
231 affs_empty_dir(struct inode *inode)
232 {
233 struct super_block *sb = inode->i_sb;
234 struct buffer_head *bh;
235 int retval, size;
237 retval = -EIO;
238 bh = affs_bread(sb, inode->i_ino);
239 if (!bh)
240 goto done;
242 retval = -ENOTEMPTY;
243 for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
244 if (AFFS_HEAD(bh)->table[size])
245 goto not_empty;
246 retval = 0;
247 not_empty:
248 affs_brelse(bh);
249 done:
250 return retval;
251 }
254 /* Remove a filesystem object. If the object to be removed has
255 * links to it, one of the links must be changed to inherit
256 * the file or directory. As above, any inode will do.
257 * The buffer will not be freed. If the header is a link, the
258 * block will be marked as free.
259 * This function returns a negative error number in case of
260 * an error, else 0 if the inode is to be deleted or 1 if not.
261 */
263 int
264 affs_remove_header(struct dentry *dentry)
265 {
266 struct super_block *sb;
267 struct inode *inode, *dir;
268 struct buffer_head *bh = NULL;
269 int retval;
271 dir = dentry->d_parent->d_inode;
272 sb = dir->i_sb;
274 retval = -ENOENT;
275 inode = dentry->d_inode;
276 if (!inode)
277 goto done;
279 pr_debug("AFFS: remove_header(key=%ld)\n", inode->i_ino);
280 retval = -EIO;
281 bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
282 if (!bh)
283 goto done;
285 affs_lock_link(inode);
286 affs_lock_dir(dir);
287 switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
288 case ST_USERDIR:
289 /* if we ever want to support links to dirs
290 * i_hash_lock of the inode must only be
291 * taken after some checks
292 */
293 affs_lock_dir(inode);
294 retval = affs_empty_dir(inode);
295 affs_unlock_dir(inode);
296 if (retval)
297 goto done_unlock;
298 break;
299 default:
300 break;
301 }
303 retval = affs_remove_hash(dir, bh);
304 if (retval)
305 goto done_unlock;
306 mark_buffer_dirty_inode(bh, inode);
308 affs_unlock_dir(dir);
310 if (inode->i_nlink > 1)
311 retval = affs_remove_link(dentry);
312 else
313 inode->i_nlink = 0;
314 affs_unlock_link(inode);
315 inode->i_ctime = CURRENT_TIME_SEC;
316 mark_inode_dirty(inode);
318 done:
319 affs_brelse(bh);
320 return retval;
322 done_unlock:
323 affs_unlock_dir(dir);
324 affs_unlock_link(inode);
325 goto done;
326 }
328 /* Checksum a block, do various consistency checks and optionally return
329 the blocks type number. DATA points to the block. If their pointers
330 are non-null, *PTYPE and *STYPE are set to the primary and secondary
331 block types respectively, *HASHSIZE is set to the size of the hashtable
332 (which lets us calculate the block size).
333 Returns non-zero if the block is not consistent. */
335 u32
336 affs_checksum_block(struct super_block *sb, struct buffer_head *bh)
337 {
338 __be32 *ptr = (__be32 *)bh->b_data;
339 u32 sum;
340 int bsize;
342 sum = 0;
343 for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
344 sum += be32_to_cpu(*ptr++);
345 return sum;
346 }
348 /*
349 * Calculate the checksum of a disk block and store it
350 * at the indicated position.
351 */
353 void
354 affs_fix_checksum(struct super_block *sb, struct buffer_head *bh)
355 {
356 int cnt = sb->s_blocksize / sizeof(__be32);
357 __be32 *ptr = (__be32 *)bh->b_data;
358 u32 checksum;
359 __be32 *checksumptr;
361 checksumptr = ptr + 5;
362 *checksumptr = 0;
363 for (checksum = 0; cnt > 0; ptr++, cnt--)
364 checksum += be32_to_cpu(*ptr);
365 *checksumptr = cpu_to_be32(-checksum);
366 }
368 void
369 secs_to_datestamp(time_t secs, struct affs_date *ds)
370 {
371 u32 days;
372 u32 minute;
374 secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
375 if (secs < 0)
376 secs = 0;
377 days = secs / 86400;
378 secs -= days * 86400;
379 minute = secs / 60;
380 secs -= minute * 60;
382 ds->days = cpu_to_be32(days);
383 ds->mins = cpu_to_be32(minute);
384 ds->ticks = cpu_to_be32(secs * 50);
385 }
387 mode_t
388 prot_to_mode(u32 prot)
389 {
390 int mode = 0;
392 if (!(prot & FIBF_NOWRITE))
393 mode |= S_IWUSR;
394 if (!(prot & FIBF_NOREAD))
395 mode |= S_IRUSR;
396 if (!(prot & FIBF_NOEXECUTE))
397 mode |= S_IXUSR;
398 if (prot & FIBF_GRP_WRITE)
399 mode |= S_IWGRP;
400 if (prot & FIBF_GRP_READ)
401 mode |= S_IRGRP;
402 if (prot & FIBF_GRP_EXECUTE)
403 mode |= S_IXGRP;
404 if (prot & FIBF_OTR_WRITE)
405 mode |= S_IWOTH;
406 if (prot & FIBF_OTR_READ)
407 mode |= S_IROTH;
408 if (prot & FIBF_OTR_EXECUTE)
409 mode |= S_IXOTH;
411 return mode;
412 }
414 void
415 mode_to_prot(struct inode *inode)
416 {
417 u32 prot = AFFS_I(inode)->i_protect;
418 mode_t mode = inode->i_mode;
420 if (!(mode & S_IXUSR))
421 prot |= FIBF_NOEXECUTE;
422 if (!(mode & S_IRUSR))
423 prot |= FIBF_NOREAD;
424 if (!(mode & S_IWUSR))
425 prot |= FIBF_NOWRITE;
426 if (mode & S_IXGRP)
427 prot |= FIBF_GRP_EXECUTE;
428 if (mode & S_IRGRP)
429 prot |= FIBF_GRP_READ;
430 if (mode & S_IWGRP)
431 prot |= FIBF_GRP_WRITE;
432 if (mode & S_IXOTH)
433 prot |= FIBF_OTR_EXECUTE;
434 if (mode & S_IROTH)
435 prot |= FIBF_OTR_READ;
436 if (mode & S_IWOTH)
437 prot |= FIBF_OTR_WRITE;
439 AFFS_I(inode)->i_protect = prot;
440 }
442 void
443 affs_error(struct super_block *sb, const char *function, const char *fmt, ...)
444 {
445 va_list args;
447 va_start(args,fmt);
448 vsprintf(ErrorBuffer,fmt,args);
449 va_end(args);
451 printk(KERN_CRIT "AFFS error (device %s): %s(): %s\n", sb->s_id,
452 function,ErrorBuffer);
453 if (!(sb->s_flags & MS_RDONLY))
454 printk(KERN_WARNING "AFFS: Remounting filesystem read-only\n");
455 sb->s_flags |= MS_RDONLY;
456 }
458 void
459 affs_warning(struct super_block *sb, const char *function, const char *fmt, ...)
460 {
461 va_list args;
463 va_start(args,fmt);
464 vsprintf(ErrorBuffer,fmt,args);
465 va_end(args);
467 printk(KERN_WARNING "AFFS warning (device %s): %s(): %s\n", sb->s_id,
468 function,ErrorBuffer);
469 }
471 /* Check if the name is valid for a affs object. */
473 int
474 affs_check_name(const unsigned char *name, int len)
475 {
476 int i;
478 if (len > 30)
479 #ifdef AFFS_NO_TRUNCATE
480 return -ENAMETOOLONG;
481 #else
482 len = 30;
483 #endif
485 for (i = 0; i < len; i++) {
486 if (name[i] < ' ' || name[i] == ':'
487 || (name[i] > 0x7e && name[i] < 0xa0))
488 return -EINVAL;
489 }
491 return 0;
492 }
494 /* This function copies name to bstr, with at most 30
495 * characters length. The bstr will be prepended by
496 * a length byte.
497 * NOTE: The name will must be already checked by
498 * affs_check_name()!
499 */
501 int
502 affs_copy_name(unsigned char *bstr, struct dentry *dentry)
503 {
504 int len = min(dentry->d_name.len, 30u);
506 *bstr++ = len;
507 memcpy(bstr, dentry->d_name.name, len);
508 return len;
509 }