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inode.c
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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  i_uid_write(inode, 0);
84  else
85  i_uid_write(inode, 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  i_gid_write(inode, 0);
92  else
93  i_gid_write(inode, 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 = i_uid_read(inode);
197  gid = i_gid_read(inode);
198  if (AFFS_SB(sb)->s_flags & SF_MUFS) {
199  if (uid == 0 || uid == 0xFFFF)
200  uid = uid ^ ~0;
201  if (gid == 0 || gid == 0xFFFF)
202  gid = 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  clear_inode(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 }
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