xref: /linux/fs/affs/inode.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
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_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("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("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 = inode_newsize_ok(inode, attr->ia_size);
241 		if (error)
242 			return error;
243 
244 		truncate_setsize(inode, attr->ia_size);
245 		affs_truncate(inode);
246 	}
247 
248 	setattr_copy(inode, attr);
249 	mark_inode_dirty(inode);
250 
251 	if (attr->ia_valid & ATTR_MODE)
252 		mode_to_prot(inode);
253 out:
254 	return error;
255 }
256 
257 void
258 affs_evict_inode(struct inode *inode)
259 {
260 	unsigned long cache_page;
261 	pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
262 		 inode->i_ino, inode->i_nlink);
263 	truncate_inode_pages_final(&inode->i_data);
264 
265 	if (!inode->i_nlink) {
266 		inode->i_size = 0;
267 		affs_truncate(inode);
268 	}
269 
270 	invalidate_inode_buffers(inode);
271 	clear_inode(inode);
272 	affs_free_prealloc(inode);
273 	cache_page = (unsigned long)AFFS_I(inode)->i_lc;
274 	if (cache_page) {
275 		pr_debug("freeing ext cache\n");
276 		AFFS_I(inode)->i_lc = NULL;
277 		AFFS_I(inode)->i_ac = NULL;
278 		free_page(cache_page);
279 	}
280 	affs_brelse(AFFS_I(inode)->i_ext_bh);
281 	AFFS_I(inode)->i_ext_last = ~1;
282 	AFFS_I(inode)->i_ext_bh = NULL;
283 
284 	if (!inode->i_nlink)
285 		affs_free_block(inode->i_sb, inode->i_ino);
286 }
287 
288 struct inode *
289 affs_new_inode(struct inode *dir)
290 {
291 	struct super_block	*sb = dir->i_sb;
292 	struct inode		*inode;
293 	u32			 block;
294 	struct buffer_head	*bh;
295 
296 	if (!(inode = new_inode(sb)))
297 		goto err_inode;
298 
299 	if (!(block = affs_alloc_block(dir, dir->i_ino)))
300 		goto err_block;
301 
302 	bh = affs_getzeroblk(sb, block);
303 	if (!bh)
304 		goto err_bh;
305 	mark_buffer_dirty_inode(bh, inode);
306 	affs_brelse(bh);
307 
308 	inode->i_uid     = current_fsuid();
309 	inode->i_gid     = current_fsgid();
310 	inode->i_ino     = block;
311 	set_nlink(inode, 1);
312 	inode->i_mtime   = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
313 	atomic_set(&AFFS_I(inode)->i_opencnt, 0);
314 	AFFS_I(inode)->i_blkcnt = 0;
315 	AFFS_I(inode)->i_lc = NULL;
316 	AFFS_I(inode)->i_lc_size = 0;
317 	AFFS_I(inode)->i_lc_shift = 0;
318 	AFFS_I(inode)->i_lc_mask = 0;
319 	AFFS_I(inode)->i_ac = NULL;
320 	AFFS_I(inode)->i_ext_bh = NULL;
321 	AFFS_I(inode)->mmu_private = 0;
322 	AFFS_I(inode)->i_protect = 0;
323 	AFFS_I(inode)->i_lastalloc = 0;
324 	AFFS_I(inode)->i_pa_cnt = 0;
325 	AFFS_I(inode)->i_extcnt = 1;
326 	AFFS_I(inode)->i_ext_last = ~1;
327 
328 	insert_inode_hash(inode);
329 
330 	return inode;
331 
332 err_bh:
333 	affs_free_block(sb, block);
334 err_block:
335 	iput(inode);
336 err_inode:
337 	return NULL;
338 }
339 
340 /*
341  * Add an entry to a directory. Create the header block
342  * and insert it into the hash table.
343  */
344 
345 int
346 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
347 {
348 	struct super_block *sb = dir->i_sb;
349 	struct buffer_head *inode_bh = NULL;
350 	struct buffer_head *bh = NULL;
351 	u32 block = 0;
352 	int retval;
353 
354 	pr_debug("%s(dir=%u, inode=%u, \"%*s\", type=%d)\n",
355 		 __func__, (u32)dir->i_ino,
356 	         (u32)inode->i_ino, (int)dentry->d_name.len, dentry->d_name.name, type);
357 
358 	retval = -EIO;
359 	bh = affs_bread(sb, inode->i_ino);
360 	if (!bh)
361 		goto done;
362 
363 	affs_lock_link(inode);
364 	switch (type) {
365 	case ST_LINKFILE:
366 	case ST_LINKDIR:
367 		retval = -ENOSPC;
368 		block = affs_alloc_block(dir, dir->i_ino);
369 		if (!block)
370 			goto err;
371 		retval = -EIO;
372 		inode_bh = bh;
373 		bh = affs_getzeroblk(sb, block);
374 		if (!bh)
375 			goto err;
376 		break;
377 	default:
378 		break;
379 	}
380 
381 	AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
382 	AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
383 	affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
384 	AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
385 	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
386 
387 	if (inode_bh) {
388 		__be32 chain;
389 	       	chain = AFFS_TAIL(sb, inode_bh)->link_chain;
390 		AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
391 		AFFS_TAIL(sb, bh)->link_chain = chain;
392 		AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
393 		affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
394 		mark_buffer_dirty_inode(inode_bh, inode);
395 		set_nlink(inode, 2);
396 		ihold(inode);
397 	}
398 	affs_fix_checksum(sb, bh);
399 	mark_buffer_dirty_inode(bh, inode);
400 	dentry->d_fsdata = (void *)(long)bh->b_blocknr;
401 
402 	affs_lock_dir(dir);
403 	retval = affs_insert_hash(dir, bh);
404 	mark_buffer_dirty_inode(bh, inode);
405 	affs_unlock_dir(dir);
406 	affs_unlock_link(inode);
407 
408 	d_instantiate(dentry, inode);
409 done:
410 	affs_brelse(inode_bh);
411 	affs_brelse(bh);
412 	return retval;
413 err:
414 	if (block)
415 		affs_free_block(sb, block);
416 	affs_unlock_link(inode);
417 	goto done;
418 }
419