xref: /linux/fs/affs/inode.c (revision 6bc51cbaa9d75c7c240282da5ff270815caccac0)
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/cred.h>
14 #include <linux/gfp.h>
15 #include "affs.h"
16 
17 struct inode *affs_iget(struct super_block *sb, unsigned long ino)
18 {
19 	struct affs_sb_info	*sbi = AFFS_SB(sb);
20 	struct buffer_head	*bh;
21 	struct affs_tail	*tail;
22 	struct inode		*inode;
23 	u32			 block;
24 	u32			 size;
25 	u32			 prot;
26 	u16			 id;
27 
28 	inode = iget_locked(sb, ino);
29 	if (!inode)
30 		return ERR_PTR(-ENOMEM);
31 	if (!(inode->i_state & I_NEW))
32 		return inode;
33 
34 	pr_debug("affs_iget(%lu)\n", inode->i_ino);
35 
36 	block = inode->i_ino;
37 	bh = affs_bread(sb, block);
38 	if (!bh) {
39 		affs_warning(sb, "read_inode", "Cannot read block %d", block);
40 		goto bad_inode;
41 	}
42 	if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
43 		affs_warning(sb,"read_inode",
44 			   "Checksum or type (ptype=%d) error on inode %d",
45 			   AFFS_HEAD(bh)->ptype, block);
46 		goto bad_inode;
47 	}
48 
49 	tail = AFFS_TAIL(sb, bh);
50 	prot = be32_to_cpu(tail->protect);
51 
52 	inode->i_size = 0;
53 	set_nlink(inode, 1);
54 	inode->i_mode = 0;
55 	AFFS_I(inode)->i_extcnt = 1;
56 	AFFS_I(inode)->i_ext_last = ~1;
57 	AFFS_I(inode)->i_protect = prot;
58 	atomic_set(&AFFS_I(inode)->i_opencnt, 0);
59 	AFFS_I(inode)->i_blkcnt = 0;
60 	AFFS_I(inode)->i_lc = NULL;
61 	AFFS_I(inode)->i_lc_size = 0;
62 	AFFS_I(inode)->i_lc_shift = 0;
63 	AFFS_I(inode)->i_lc_mask = 0;
64 	AFFS_I(inode)->i_ac = NULL;
65 	AFFS_I(inode)->i_ext_bh = NULL;
66 	AFFS_I(inode)->mmu_private = 0;
67 	AFFS_I(inode)->i_lastalloc = 0;
68 	AFFS_I(inode)->i_pa_cnt = 0;
69 
70 	if (affs_test_opt(sbi->s_flags, SF_SETMODE))
71 		inode->i_mode = sbi->s_mode;
72 	else
73 		inode->i_mode = affs_prot_to_mode(prot);
74 
75 	id = be16_to_cpu(tail->uid);
76 	if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETUID))
77 		inode->i_uid = sbi->s_uid;
78 	else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
79 		i_uid_write(inode, 0);
80 	else
81 		i_uid_write(inode, id);
82 
83 	id = be16_to_cpu(tail->gid);
84 	if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETGID))
85 		inode->i_gid = sbi->s_gid;
86 	else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
87 		i_gid_write(inode, 0);
88 	else
89 		i_gid_write(inode, id);
90 
91 	switch (be32_to_cpu(tail->stype)) {
92 	case ST_ROOT:
93 		inode->i_uid = sbi->s_uid;
94 		inode->i_gid = sbi->s_gid;
95 		/* fall through */
96 	case ST_USERDIR:
97 		if (be32_to_cpu(tail->stype) == ST_USERDIR ||
98 		    affs_test_opt(sbi->s_flags, SF_SETMODE)) {
99 			if (inode->i_mode & S_IRUSR)
100 				inode->i_mode |= S_IXUSR;
101 			if (inode->i_mode & S_IRGRP)
102 				inode->i_mode |= S_IXGRP;
103 			if (inode->i_mode & S_IROTH)
104 				inode->i_mode |= S_IXOTH;
105 			inode->i_mode |= S_IFDIR;
106 		} else
107 			inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
108 		/* Maybe it should be controlled by mount parameter? */
109 		//inode->i_mode |= S_ISVTX;
110 		inode->i_op = &affs_dir_inode_operations;
111 		inode->i_fop = &affs_dir_operations;
112 		break;
113 	case ST_LINKDIR:
114 #if 0
115 		affs_warning(sb, "read_inode", "inode is LINKDIR");
116 		goto bad_inode;
117 #else
118 		inode->i_mode |= S_IFDIR;
119 		/* ... and leave ->i_op and ->i_fop pointing to empty */
120 		break;
121 #endif
122 	case ST_LINKFILE:
123 		affs_warning(sb, "read_inode", "inode is LINKFILE");
124 		goto bad_inode;
125 	case ST_FILE:
126 		size = be32_to_cpu(tail->size);
127 		inode->i_mode |= S_IFREG;
128 		AFFS_I(inode)->mmu_private = inode->i_size = size;
129 		if (inode->i_size) {
130 			AFFS_I(inode)->i_blkcnt = (size - 1) /
131 					       sbi->s_data_blksize + 1;
132 			AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
133 					       sbi->s_hashsize + 1;
134 		}
135 		if (tail->link_chain)
136 			set_nlink(inode, 2);
137 		inode->i_mapping->a_ops = affs_test_opt(sbi->s_flags, SF_OFS) ?
138 					  &affs_aops_ofs : &affs_aops;
139 		inode->i_op = &affs_file_inode_operations;
140 		inode->i_fop = &affs_file_operations;
141 		break;
142 	case ST_SOFTLINK:
143 		inode->i_size = strlen((char *)AFFS_HEAD(bh)->table);
144 		inode->i_mode |= S_IFLNK;
145 		inode_nohighmem(inode);
146 		inode->i_op = &affs_symlink_inode_operations;
147 		inode->i_data.a_ops = &affs_symlink_aops;
148 		break;
149 	}
150 
151 	inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec
152 		       = (be32_to_cpu(tail->change.days) * (24 * 60 * 60) +
153 		         be32_to_cpu(tail->change.mins) * 60 +
154 			 be32_to_cpu(tail->change.ticks) / 50 +
155 			 ((8 * 365 + 2) * 24 * 60 * 60)) +
156 			 sys_tz.tz_minuteswest * 60;
157 	inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;
158 	affs_brelse(bh);
159 	unlock_new_inode(inode);
160 	return inode;
161 
162 bad_inode:
163 	affs_brelse(bh);
164 	iget_failed(inode);
165 	return ERR_PTR(-EIO);
166 }
167 
168 int
169 affs_write_inode(struct inode *inode, struct writeback_control *wbc)
170 {
171 	struct super_block	*sb = inode->i_sb;
172 	struct buffer_head	*bh;
173 	struct affs_tail	*tail;
174 	uid_t			 uid;
175 	gid_t			 gid;
176 
177 	pr_debug("write_inode(%lu)\n", inode->i_ino);
178 
179 	if (!inode->i_nlink)
180 		// possibly free block
181 		return 0;
182 	bh = affs_bread(sb, inode->i_ino);
183 	if (!bh) {
184 		affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
185 		return -EIO;
186 	}
187 	tail = AFFS_TAIL(sb, bh);
188 	if (tail->stype == cpu_to_be32(ST_ROOT)) {
189 		affs_secs_to_datestamp(inode->i_mtime.tv_sec,
190 				       &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 		affs_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_test_opt(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_test_opt(AFFS_SB(sb)->s_flags, SF_SETUID))
205 				tail->uid = cpu_to_be16(uid);
206 			if (!affs_test_opt(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 = d_inode(dentry);
221 	int error;
222 
223 	pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
224 
225 	error = setattr_prepare(dentry, attr);
226 	if (error)
227 		goto out;
228 
229 	if (((attr->ia_valid & ATTR_UID) &&
230 	      affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETUID)) ||
231 	    ((attr->ia_valid & ATTR_GID) &&
232 	      affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETGID)) ||
233 	    ((attr->ia_valid & ATTR_MODE) &&
234 	     (AFFS_SB(inode->i_sb)->s_flags &
235 	      (AFFS_MOUNT_SF_SETMODE | AFFS_MOUNT_SF_IMMUTABLE)))) {
236 		if (!affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_QUIET))
237 			error = -EPERM;
238 		goto out;
239 	}
240 
241 	if ((attr->ia_valid & ATTR_SIZE) &&
242 	    attr->ia_size != i_size_read(inode)) {
243 		error = inode_newsize_ok(inode, attr->ia_size);
244 		if (error)
245 			return error;
246 
247 		truncate_setsize(inode, attr->ia_size);
248 		affs_truncate(inode);
249 	}
250 
251 	setattr_copy(inode, attr);
252 	mark_inode_dirty(inode);
253 
254 	if (attr->ia_valid & ATTR_MODE)
255 		affs_mode_to_prot(inode);
256 out:
257 	return error;
258 }
259 
260 void
261 affs_evict_inode(struct inode *inode)
262 {
263 	unsigned long cache_page;
264 	pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
265 		 inode->i_ino, inode->i_nlink);
266 	truncate_inode_pages_final(&inode->i_data);
267 
268 	if (!inode->i_nlink) {
269 		inode->i_size = 0;
270 		affs_truncate(inode);
271 	}
272 
273 	invalidate_inode_buffers(inode);
274 	clear_inode(inode);
275 	affs_free_prealloc(inode);
276 	cache_page = (unsigned long)AFFS_I(inode)->i_lc;
277 	if (cache_page) {
278 		pr_debug("freeing ext cache\n");
279 		AFFS_I(inode)->i_lc = NULL;
280 		AFFS_I(inode)->i_ac = NULL;
281 		free_page(cache_page);
282 	}
283 	affs_brelse(AFFS_I(inode)->i_ext_bh);
284 	AFFS_I(inode)->i_ext_last = ~1;
285 	AFFS_I(inode)->i_ext_bh = NULL;
286 
287 	if (!inode->i_nlink)
288 		affs_free_block(inode->i_sb, inode->i_ino);
289 }
290 
291 struct inode *
292 affs_new_inode(struct inode *dir)
293 {
294 	struct super_block	*sb = dir->i_sb;
295 	struct inode		*inode;
296 	u32			 block;
297 	struct buffer_head	*bh;
298 
299 	if (!(inode = new_inode(sb)))
300 		goto err_inode;
301 
302 	if (!(block = affs_alloc_block(dir, dir->i_ino)))
303 		goto err_block;
304 
305 	bh = affs_getzeroblk(sb, block);
306 	if (!bh)
307 		goto err_bh;
308 	mark_buffer_dirty_inode(bh, inode);
309 	affs_brelse(bh);
310 
311 	inode->i_uid     = current_fsuid();
312 	inode->i_gid     = current_fsgid();
313 	inode->i_ino     = block;
314 	set_nlink(inode, 1);
315 	inode->i_mtime   = inode->i_atime = inode->i_ctime = current_time(inode);
316 	atomic_set(&AFFS_I(inode)->i_opencnt, 0);
317 	AFFS_I(inode)->i_blkcnt = 0;
318 	AFFS_I(inode)->i_lc = NULL;
319 	AFFS_I(inode)->i_lc_size = 0;
320 	AFFS_I(inode)->i_lc_shift = 0;
321 	AFFS_I(inode)->i_lc_mask = 0;
322 	AFFS_I(inode)->i_ac = NULL;
323 	AFFS_I(inode)->i_ext_bh = NULL;
324 	AFFS_I(inode)->mmu_private = 0;
325 	AFFS_I(inode)->i_protect = 0;
326 	AFFS_I(inode)->i_lastalloc = 0;
327 	AFFS_I(inode)->i_pa_cnt = 0;
328 	AFFS_I(inode)->i_extcnt = 1;
329 	AFFS_I(inode)->i_ext_last = ~1;
330 
331 	insert_inode_hash(inode);
332 
333 	return inode;
334 
335 err_bh:
336 	affs_free_block(sb, block);
337 err_block:
338 	iput(inode);
339 err_inode:
340 	return NULL;
341 }
342 
343 /*
344  * Add an entry to a directory. Create the header block
345  * and insert it into the hash table.
346  */
347 
348 int
349 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
350 {
351 	struct super_block *sb = dir->i_sb;
352 	struct buffer_head *inode_bh = NULL;
353 	struct buffer_head *bh;
354 	u32 block = 0;
355 	int retval;
356 
357 	pr_debug("%s(dir=%lu, inode=%lu, \"%pd\", type=%d)\n", __func__,
358 		 dir->i_ino, inode->i_ino, dentry, type);
359 
360 	retval = -EIO;
361 	bh = affs_bread(sb, inode->i_ino);
362 	if (!bh)
363 		goto done;
364 
365 	affs_lock_link(inode);
366 	switch (type) {
367 	case ST_LINKFILE:
368 	case ST_LINKDIR:
369 		retval = -ENOSPC;
370 		block = affs_alloc_block(dir, dir->i_ino);
371 		if (!block)
372 			goto err;
373 		retval = -EIO;
374 		inode_bh = bh;
375 		bh = affs_getzeroblk(sb, block);
376 		if (!bh)
377 			goto err;
378 		break;
379 	default:
380 		break;
381 	}
382 
383 	AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
384 	AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
385 	affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
386 	AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
387 	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
388 
389 	if (inode_bh) {
390 		__be32 chain;
391 	       	chain = AFFS_TAIL(sb, inode_bh)->link_chain;
392 		AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
393 		AFFS_TAIL(sb, bh)->link_chain = chain;
394 		AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
395 		affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
396 		mark_buffer_dirty_inode(inode_bh, inode);
397 		set_nlink(inode, 2);
398 		ihold(inode);
399 	}
400 	affs_fix_checksum(sb, bh);
401 	mark_buffer_dirty_inode(bh, inode);
402 	dentry->d_fsdata = (void *)(long)bh->b_blocknr;
403 
404 	affs_lock_dir(dir);
405 	retval = affs_insert_hash(dir, bh);
406 	mark_buffer_dirty_inode(bh, inode);
407 	affs_unlock_dir(dir);
408 	affs_unlock_link(inode);
409 
410 	d_instantiate(dentry, inode);
411 done:
412 	affs_brelse(inode_bh);
413 	affs_brelse(bh);
414 	return retval;
415 err:
416 	if (block)
417 		affs_free_block(sb, block);
418 	affs_unlock_link(inode);
419 	goto done;
420 }
421