Merge git://github.com/rustyrussell/linux
[pandora-kernel.git] / fs / affs / inode.c
1 /*
2  *  linux/fs/affs/inode.c
3  *
4  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
5  *
6  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
7  *
8  *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
9  *
10  *  (C) 1991  Linus Torvalds - minix filesystem
11  */
12 #include <linux/sched.h>
13 #include <linux/gfp.h>
14 #include "affs.h"
15
16 extern const struct inode_operations affs_symlink_inode_operations;
17 extern struct timezone sys_tz;
18
19 struct inode *affs_iget(struct super_block *sb, unsigned long ino)
20 {
21         struct affs_sb_info     *sbi = AFFS_SB(sb);
22         struct buffer_head      *bh;
23         struct affs_head        *head;
24         struct affs_tail        *tail;
25         struct inode            *inode;
26         u32                      block;
27         u32                      size;
28         u32                      prot;
29         u16                      id;
30
31         inode = iget_locked(sb, ino);
32         if (!inode)
33                 return ERR_PTR(-ENOMEM);
34         if (!(inode->i_state & I_NEW))
35                 return inode;
36
37         pr_debug("AFFS: affs_iget(%lu)\n", inode->i_ino);
38
39         block = inode->i_ino;
40         bh = affs_bread(sb, block);
41         if (!bh) {
42                 affs_warning(sb, "read_inode", "Cannot read block %d", block);
43                 goto bad_inode;
44         }
45         if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
46                 affs_warning(sb,"read_inode",
47                            "Checksum or type (ptype=%d) error on inode %d",
48                            AFFS_HEAD(bh)->ptype, block);
49                 goto bad_inode;
50         }
51
52         head = AFFS_HEAD(bh);
53         tail = AFFS_TAIL(sb, bh);
54         prot = be32_to_cpu(tail->protect);
55
56         inode->i_size = 0;
57         set_nlink(inode, 1);
58         inode->i_mode = 0;
59         AFFS_I(inode)->i_extcnt = 1;
60         AFFS_I(inode)->i_ext_last = ~1;
61         AFFS_I(inode)->i_protect = prot;
62         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
63         AFFS_I(inode)->i_blkcnt = 0;
64         AFFS_I(inode)->i_lc = NULL;
65         AFFS_I(inode)->i_lc_size = 0;
66         AFFS_I(inode)->i_lc_shift = 0;
67         AFFS_I(inode)->i_lc_mask = 0;
68         AFFS_I(inode)->i_ac = NULL;
69         AFFS_I(inode)->i_ext_bh = NULL;
70         AFFS_I(inode)->mmu_private = 0;
71         AFFS_I(inode)->i_lastalloc = 0;
72         AFFS_I(inode)->i_pa_cnt = 0;
73
74         if (sbi->s_flags & SF_SETMODE)
75                 inode->i_mode = sbi->s_mode;
76         else
77                 inode->i_mode = prot_to_mode(prot);
78
79         id = be16_to_cpu(tail->uid);
80         if (id == 0 || sbi->s_flags & SF_SETUID)
81                 inode->i_uid = sbi->s_uid;
82         else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
83                 inode->i_uid = 0;
84         else
85                 inode->i_uid = id;
86
87         id = be16_to_cpu(tail->gid);
88         if (id == 0 || sbi->s_flags & SF_SETGID)
89                 inode->i_gid = sbi->s_gid;
90         else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
91                 inode->i_gid = 0;
92         else
93                 inode->i_gid = id;
94
95         switch (be32_to_cpu(tail->stype)) {
96         case ST_ROOT:
97                 inode->i_uid = sbi->s_uid;
98                 inode->i_gid = sbi->s_gid;
99                 /* fall through */
100         case ST_USERDIR:
101                 if (be32_to_cpu(tail->stype) == ST_USERDIR ||
102                     sbi->s_flags & SF_SETMODE) {
103                         if (inode->i_mode & S_IRUSR)
104                                 inode->i_mode |= S_IXUSR;
105                         if (inode->i_mode & S_IRGRP)
106                                 inode->i_mode |= S_IXGRP;
107                         if (inode->i_mode & S_IROTH)
108                                 inode->i_mode |= S_IXOTH;
109                         inode->i_mode |= S_IFDIR;
110                 } else
111                         inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
112                 /* Maybe it should be controlled by mount parameter? */
113                 //inode->i_mode |= S_ISVTX;
114                 inode->i_op = &affs_dir_inode_operations;
115                 inode->i_fop = &affs_dir_operations;
116                 break;
117         case ST_LINKDIR:
118 #if 0
119                 affs_warning(sb, "read_inode", "inode is LINKDIR");
120                 goto bad_inode;
121 #else
122                 inode->i_mode |= S_IFDIR;
123                 /* ... and leave ->i_op and ->i_fop pointing to empty */
124                 break;
125 #endif
126         case ST_LINKFILE:
127                 affs_warning(sb, "read_inode", "inode is LINKFILE");
128                 goto bad_inode;
129         case ST_FILE:
130                 size = be32_to_cpu(tail->size);
131                 inode->i_mode |= S_IFREG;
132                 AFFS_I(inode)->mmu_private = inode->i_size = size;
133                 if (inode->i_size) {
134                         AFFS_I(inode)->i_blkcnt = (size - 1) /
135                                                sbi->s_data_blksize + 1;
136                         AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
137                                                sbi->s_hashsize + 1;
138                 }
139                 if (tail->link_chain)
140                         set_nlink(inode, 2);
141                 inode->i_mapping->a_ops = (sbi->s_flags & SF_OFS) ? &affs_aops_ofs : &affs_aops;
142                 inode->i_op = &affs_file_inode_operations;
143                 inode->i_fop = &affs_file_operations;
144                 break;
145         case ST_SOFTLINK:
146                 inode->i_mode |= S_IFLNK;
147                 inode->i_op = &affs_symlink_inode_operations;
148                 inode->i_data.a_ops = &affs_symlink_aops;
149                 break;
150         }
151
152         inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec
153                        = (be32_to_cpu(tail->change.days) * (24 * 60 * 60) +
154                          be32_to_cpu(tail->change.mins) * 60 +
155                          be32_to_cpu(tail->change.ticks) / 50 +
156                          ((8 * 365 + 2) * 24 * 60 * 60)) +
157                          sys_tz.tz_minuteswest * 60;
158         inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;
159         affs_brelse(bh);
160         unlock_new_inode(inode);
161         return inode;
162
163 bad_inode:
164         affs_brelse(bh);
165         iget_failed(inode);
166         return ERR_PTR(-EIO);
167 }
168
169 int
170 affs_write_inode(struct inode *inode, struct writeback_control *wbc)
171 {
172         struct super_block      *sb = inode->i_sb;
173         struct buffer_head      *bh;
174         struct affs_tail        *tail;
175         uid_t                    uid;
176         gid_t                    gid;
177
178         pr_debug("AFFS: write_inode(%lu)\n",inode->i_ino);
179
180         if (!inode->i_nlink)
181                 // possibly free block
182                 return 0;
183         bh = affs_bread(sb, inode->i_ino);
184         if (!bh) {
185                 affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
186                 return -EIO;
187         }
188         tail = AFFS_TAIL(sb, bh);
189         if (tail->stype == cpu_to_be32(ST_ROOT)) {
190                 secs_to_datestamp(inode->i_mtime.tv_sec,&AFFS_ROOT_TAIL(sb, bh)->root_change);
191         } else {
192                 tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
193                 tail->size = cpu_to_be32(inode->i_size);
194                 secs_to_datestamp(inode->i_mtime.tv_sec,&tail->change);
195                 if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
196                         uid = inode->i_uid;
197                         gid = inode->i_gid;
198                         if (AFFS_SB(sb)->s_flags & SF_MUFS) {
199                                 if (inode->i_uid == 0 || inode->i_uid == 0xFFFF)
200                                         uid = inode->i_uid ^ ~0;
201                                 if (inode->i_gid == 0 || inode->i_gid == 0xFFFF)
202                                         gid = inode->i_gid ^ ~0;
203                         }
204                         if (!(AFFS_SB(sb)->s_flags & SF_SETUID))
205                                 tail->uid = cpu_to_be16(uid);
206                         if (!(AFFS_SB(sb)->s_flags & SF_SETGID))
207                                 tail->gid = cpu_to_be16(gid);
208                 }
209         }
210         affs_fix_checksum(sb, bh);
211         mark_buffer_dirty_inode(bh, inode);
212         affs_brelse(bh);
213         affs_free_prealloc(inode);
214         return 0;
215 }
216
217 int
218 affs_notify_change(struct dentry *dentry, struct iattr *attr)
219 {
220         struct inode *inode = dentry->d_inode;
221         int error;
222
223         pr_debug("AFFS: notify_change(%lu,0x%x)\n",inode->i_ino,attr->ia_valid);
224
225         error = inode_change_ok(inode,attr);
226         if (error)
227                 goto out;
228
229         if (((attr->ia_valid & ATTR_UID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETUID)) ||
230             ((attr->ia_valid & ATTR_GID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETGID)) ||
231             ((attr->ia_valid & ATTR_MODE) &&
232              (AFFS_SB(inode->i_sb)->s_flags & (SF_SETMODE | SF_IMMUTABLE)))) {
233                 if (!(AFFS_SB(inode->i_sb)->s_flags & SF_QUIET))
234                         error = -EPERM;
235                 goto out;
236         }
237
238         if ((attr->ia_valid & ATTR_SIZE) &&
239             attr->ia_size != i_size_read(inode)) {
240                 error = vmtruncate(inode, attr->ia_size);
241                 if (error)
242                         return error;
243         }
244
245         setattr_copy(inode, attr);
246         mark_inode_dirty(inode);
247
248         if (attr->ia_valid & ATTR_MODE)
249                 mode_to_prot(inode);
250 out:
251         return error;
252 }
253
254 void
255 affs_evict_inode(struct inode *inode)
256 {
257         unsigned long cache_page;
258         pr_debug("AFFS: evict_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
259         truncate_inode_pages(&inode->i_data, 0);
260
261         if (!inode->i_nlink) {
262                 inode->i_size = 0;
263                 affs_truncate(inode);
264         }
265
266         invalidate_inode_buffers(inode);
267         end_writeback(inode);
268         affs_free_prealloc(inode);
269         cache_page = (unsigned long)AFFS_I(inode)->i_lc;
270         if (cache_page) {
271                 pr_debug("AFFS: freeing ext cache\n");
272                 AFFS_I(inode)->i_lc = NULL;
273                 AFFS_I(inode)->i_ac = NULL;
274                 free_page(cache_page);
275         }
276         affs_brelse(AFFS_I(inode)->i_ext_bh);
277         AFFS_I(inode)->i_ext_last = ~1;
278         AFFS_I(inode)->i_ext_bh = NULL;
279
280         if (!inode->i_nlink)
281                 affs_free_block(inode->i_sb, inode->i_ino);
282 }
283
284 struct inode *
285 affs_new_inode(struct inode *dir)
286 {
287         struct super_block      *sb = dir->i_sb;
288         struct inode            *inode;
289         u32                      block;
290         struct buffer_head      *bh;
291
292         if (!(inode = new_inode(sb)))
293                 goto err_inode;
294
295         if (!(block = affs_alloc_block(dir, dir->i_ino)))
296                 goto err_block;
297
298         bh = affs_getzeroblk(sb, block);
299         if (!bh)
300                 goto err_bh;
301         mark_buffer_dirty_inode(bh, inode);
302         affs_brelse(bh);
303
304         inode->i_uid     = current_fsuid();
305         inode->i_gid     = current_fsgid();
306         inode->i_ino     = block;
307         set_nlink(inode, 1);
308         inode->i_mtime   = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
309         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
310         AFFS_I(inode)->i_blkcnt = 0;
311         AFFS_I(inode)->i_lc = NULL;
312         AFFS_I(inode)->i_lc_size = 0;
313         AFFS_I(inode)->i_lc_shift = 0;
314         AFFS_I(inode)->i_lc_mask = 0;
315         AFFS_I(inode)->i_ac = NULL;
316         AFFS_I(inode)->i_ext_bh = NULL;
317         AFFS_I(inode)->mmu_private = 0;
318         AFFS_I(inode)->i_protect = 0;
319         AFFS_I(inode)->i_lastalloc = 0;
320         AFFS_I(inode)->i_pa_cnt = 0;
321         AFFS_I(inode)->i_extcnt = 1;
322         AFFS_I(inode)->i_ext_last = ~1;
323
324         insert_inode_hash(inode);
325
326         return inode;
327
328 err_bh:
329         affs_free_block(sb, block);
330 err_block:
331         iput(inode);
332 err_inode:
333         return NULL;
334 }
335
336 /*
337  * Add an entry to a directory. Create the header block
338  * and insert it into the hash table.
339  */
340
341 int
342 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
343 {
344         struct super_block *sb = dir->i_sb;
345         struct buffer_head *inode_bh = NULL;
346         struct buffer_head *bh = NULL;
347         u32 block = 0;
348         int retval;
349
350         pr_debug("AFFS: add_entry(dir=%u, inode=%u, \"%*s\", type=%d)\n", (u32)dir->i_ino,
351                  (u32)inode->i_ino, (int)dentry->d_name.len, dentry->d_name.name, type);
352
353         retval = -EIO;
354         bh = affs_bread(sb, inode->i_ino);
355         if (!bh)
356                 goto done;
357
358         affs_lock_link(inode);
359         switch (type) {
360         case ST_LINKFILE:
361         case ST_LINKDIR:
362                 retval = -ENOSPC;
363                 block = affs_alloc_block(dir, dir->i_ino);
364                 if (!block)
365                         goto err;
366                 retval = -EIO;
367                 inode_bh = bh;
368                 bh = affs_getzeroblk(sb, block);
369                 if (!bh)
370                         goto err;
371                 break;
372         default:
373                 break;
374         }
375
376         AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
377         AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
378         affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
379         AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
380         AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
381
382         if (inode_bh) {
383                 __be32 chain;
384                 chain = AFFS_TAIL(sb, inode_bh)->link_chain;
385                 AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
386                 AFFS_TAIL(sb, bh)->link_chain = chain;
387                 AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
388                 affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
389                 mark_buffer_dirty_inode(inode_bh, inode);
390                 set_nlink(inode, 2);
391                 ihold(inode);
392         }
393         affs_fix_checksum(sb, bh);
394         mark_buffer_dirty_inode(bh, inode);
395         dentry->d_fsdata = (void *)(long)bh->b_blocknr;
396
397         affs_lock_dir(dir);
398         retval = affs_insert_hash(dir, bh);
399         mark_buffer_dirty_inode(bh, inode);
400         affs_unlock_dir(dir);
401         affs_unlock_link(inode);
402
403         d_instantiate(dentry, inode);
404 done:
405         affs_brelse(inode_bh);
406         affs_brelse(bh);
407         return retval;
408 err:
409         if (block)
410                 affs_free_block(sb, block);
411         affs_unlock_link(inode);
412         goto done;
413 }