xref: /linux/fs/affs/inode.c (revision a1c3be890440a1769ed6f822376a3e3ab0d42994)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/affs/inode.c
4  *
5  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
6  *
7  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
8  *
9  *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
10  *
11  *  (C) 1991  Linus Torvalds - minix filesystem
12  */
13 #include <linux/sched.h>
14 #include <linux/cred.h>
15 #include <linux/gfp.h>
16 #include "affs.h"
17 
18 struct inode *affs_iget(struct super_block *sb, unsigned long ino)
19 {
20 	struct affs_sb_info	*sbi = AFFS_SB(sb);
21 	struct buffer_head	*bh;
22 	struct affs_tail	*tail;
23 	struct inode		*inode;
24 	u32			 block;
25 	u32			 size;
26 	u32			 prot;
27 	u16			 id;
28 
29 	inode = iget_locked(sb, ino);
30 	if (!inode)
31 		return ERR_PTR(-ENOMEM);
32 	if (!(inode->i_state & I_NEW))
33 		return inode;
34 
35 	pr_debug("affs_iget(%lu)\n", inode->i_ino);
36 
37 	block = inode->i_ino;
38 	bh = affs_bread(sb, block);
39 	if (!bh) {
40 		affs_warning(sb, "read_inode", "Cannot read block %d", block);
41 		goto bad_inode;
42 	}
43 	if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
44 		affs_warning(sb,"read_inode",
45 			   "Checksum or type (ptype=%d) error on inode %d",
46 			   AFFS_HEAD(bh)->ptype, block);
47 		goto bad_inode;
48 	}
49 
50 	tail = AFFS_TAIL(sb, bh);
51 	prot = be32_to_cpu(tail->protect);
52 
53 	inode->i_size = 0;
54 	set_nlink(inode, 1);
55 	inode->i_mode = 0;
56 	AFFS_I(inode)->i_extcnt = 1;
57 	AFFS_I(inode)->i_ext_last = ~1;
58 	AFFS_I(inode)->i_protect = prot;
59 	atomic_set(&AFFS_I(inode)->i_opencnt, 0);
60 	AFFS_I(inode)->i_blkcnt = 0;
61 	AFFS_I(inode)->i_lc = NULL;
62 	AFFS_I(inode)->i_lc_size = 0;
63 	AFFS_I(inode)->i_lc_shift = 0;
64 	AFFS_I(inode)->i_lc_mask = 0;
65 	AFFS_I(inode)->i_ac = NULL;
66 	AFFS_I(inode)->i_ext_bh = NULL;
67 	AFFS_I(inode)->mmu_private = 0;
68 	AFFS_I(inode)->i_lastalloc = 0;
69 	AFFS_I(inode)->i_pa_cnt = 0;
70 
71 	if (affs_test_opt(sbi->s_flags, SF_SETMODE))
72 		inode->i_mode = sbi->s_mode;
73 	else
74 		inode->i_mode = affs_prot_to_mode(prot);
75 
76 	id = be16_to_cpu(tail->uid);
77 	if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETUID))
78 		inode->i_uid = sbi->s_uid;
79 	else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
80 		i_uid_write(inode, 0);
81 	else
82 		i_uid_write(inode, id);
83 
84 	id = be16_to_cpu(tail->gid);
85 	if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETGID))
86 		inode->i_gid = sbi->s_gid;
87 	else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
88 		i_gid_write(inode, 0);
89 	else
90 		i_gid_write(inode, id);
91 
92 	switch (be32_to_cpu(tail->stype)) {
93 	case ST_ROOT:
94 		inode->i_uid = sbi->s_uid;
95 		inode->i_gid = sbi->s_gid;
96 		fallthrough;
97 	case ST_USERDIR:
98 		if (be32_to_cpu(tail->stype) == ST_USERDIR ||
99 		    affs_test_opt(sbi->s_flags, SF_SETMODE)) {
100 			if (inode->i_mode & S_IRUSR)
101 				inode->i_mode |= S_IXUSR;
102 			if (inode->i_mode & S_IRGRP)
103 				inode->i_mode |= S_IXGRP;
104 			if (inode->i_mode & S_IROTH)
105 				inode->i_mode |= S_IXOTH;
106 			inode->i_mode |= S_IFDIR;
107 		} else
108 			inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
109 		/* Maybe it should be controlled by mount parameter? */
110 		//inode->i_mode |= S_ISVTX;
111 		inode->i_op = &affs_dir_inode_operations;
112 		inode->i_fop = &affs_dir_operations;
113 		break;
114 	case ST_LINKDIR:
115 #if 0
116 		affs_warning(sb, "read_inode", "inode is LINKDIR");
117 		goto bad_inode;
118 #else
119 		inode->i_mode |= S_IFDIR;
120 		/* ... and leave ->i_op and ->i_fop pointing to empty */
121 		break;
122 #endif
123 	case ST_LINKFILE:
124 		affs_warning(sb, "read_inode", "inode is LINKFILE");
125 		goto bad_inode;
126 	case ST_FILE:
127 		size = be32_to_cpu(tail->size);
128 		inode->i_mode |= S_IFREG;
129 		AFFS_I(inode)->mmu_private = inode->i_size = size;
130 		if (inode->i_size) {
131 			AFFS_I(inode)->i_blkcnt = (size - 1) /
132 					       sbi->s_data_blksize + 1;
133 			AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
134 					       sbi->s_hashsize + 1;
135 		}
136 		if (tail->link_chain)
137 			set_nlink(inode, 2);
138 		inode->i_mapping->a_ops = affs_test_opt(sbi->s_flags, SF_OFS) ?
139 					  &affs_aops_ofs : &affs_aops;
140 		inode->i_op = &affs_file_inode_operations;
141 		inode->i_fop = &affs_file_operations;
142 		break;
143 	case ST_SOFTLINK:
144 		inode->i_size = strlen((char *)AFFS_HEAD(bh)->table);
145 		inode->i_mode |= S_IFLNK;
146 		inode_nohighmem(inode);
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) * 86400LL +
154 		         be32_to_cpu(tail->change.mins) * 60 +
155 			 be32_to_cpu(tail->change.ticks) / 50 +
156 			 AFFS_EPOCH_DELTA) +
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 		affs_secs_to_datestamp(inode->i_mtime.tv_sec,
191 				       &AFFS_ROOT_TAIL(sb, bh)->root_change);
192 	} else {
193 		tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
194 		tail->size = cpu_to_be32(inode->i_size);
195 		affs_secs_to_datestamp(inode->i_mtime.tv_sec, &tail->change);
196 		if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
197 			uid = i_uid_read(inode);
198 			gid = i_gid_read(inode);
199 			if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_MUFS)) {
200 				if (uid == 0 || uid == 0xFFFF)
201 					uid = uid ^ ~0;
202 				if (gid == 0 || gid == 0xFFFF)
203 					gid = gid ^ ~0;
204 			}
205 			if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETUID))
206 				tail->uid = cpu_to_be16(uid);
207 			if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETGID))
208 				tail->gid = cpu_to_be16(gid);
209 		}
210 	}
211 	affs_fix_checksum(sb, bh);
212 	mark_buffer_dirty_inode(bh, inode);
213 	affs_brelse(bh);
214 	affs_free_prealloc(inode);
215 	return 0;
216 }
217 
218 int
219 affs_notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
220 		   struct iattr *attr)
221 {
222 	struct inode *inode = d_inode(dentry);
223 	int error;
224 
225 	pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
226 
227 	error = setattr_prepare(&init_user_ns, dentry, attr);
228 	if (error)
229 		goto out;
230 
231 	if (((attr->ia_valid & ATTR_UID) &&
232 	      affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETUID)) ||
233 	    ((attr->ia_valid & ATTR_GID) &&
234 	      affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETGID)) ||
235 	    ((attr->ia_valid & ATTR_MODE) &&
236 	     (AFFS_SB(inode->i_sb)->s_flags &
237 	      (AFFS_MOUNT_SF_SETMODE | AFFS_MOUNT_SF_IMMUTABLE)))) {
238 		if (!affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_QUIET))
239 			error = -EPERM;
240 		goto out;
241 	}
242 
243 	if ((attr->ia_valid & ATTR_SIZE) &&
244 	    attr->ia_size != i_size_read(inode)) {
245 		error = inode_newsize_ok(inode, attr->ia_size);
246 		if (error)
247 			return error;
248 
249 		truncate_setsize(inode, attr->ia_size);
250 		affs_truncate(inode);
251 	}
252 
253 	setattr_copy(&init_user_ns, inode, attr);
254 	mark_inode_dirty(inode);
255 
256 	if (attr->ia_valid & ATTR_MODE)
257 		affs_mode_to_prot(inode);
258 out:
259 	return error;
260 }
261 
262 void
263 affs_evict_inode(struct inode *inode)
264 {
265 	unsigned long cache_page;
266 	pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
267 		 inode->i_ino, inode->i_nlink);
268 	truncate_inode_pages_final(&inode->i_data);
269 
270 	if (!inode->i_nlink) {
271 		inode->i_size = 0;
272 		affs_truncate(inode);
273 	}
274 
275 	invalidate_inode_buffers(inode);
276 	clear_inode(inode);
277 	affs_free_prealloc(inode);
278 	cache_page = (unsigned long)AFFS_I(inode)->i_lc;
279 	if (cache_page) {
280 		pr_debug("freeing ext cache\n");
281 		AFFS_I(inode)->i_lc = NULL;
282 		AFFS_I(inode)->i_ac = NULL;
283 		free_page(cache_page);
284 	}
285 	affs_brelse(AFFS_I(inode)->i_ext_bh);
286 	AFFS_I(inode)->i_ext_last = ~1;
287 	AFFS_I(inode)->i_ext_bh = NULL;
288 
289 	if (!inode->i_nlink)
290 		affs_free_block(inode->i_sb, inode->i_ino);
291 }
292 
293 struct inode *
294 affs_new_inode(struct inode *dir)
295 {
296 	struct super_block	*sb = dir->i_sb;
297 	struct inode		*inode;
298 	u32			 block;
299 	struct buffer_head	*bh;
300 
301 	if (!(inode = new_inode(sb)))
302 		goto err_inode;
303 
304 	if (!(block = affs_alloc_block(dir, dir->i_ino)))
305 		goto err_block;
306 
307 	bh = affs_getzeroblk(sb, block);
308 	if (!bh)
309 		goto err_bh;
310 	mark_buffer_dirty_inode(bh, inode);
311 	affs_brelse(bh);
312 
313 	inode->i_uid     = current_fsuid();
314 	inode->i_gid     = current_fsgid();
315 	inode->i_ino     = block;
316 	set_nlink(inode, 1);
317 	inode->i_mtime   = inode->i_atime = inode->i_ctime = current_time(inode);
318 	atomic_set(&AFFS_I(inode)->i_opencnt, 0);
319 	AFFS_I(inode)->i_blkcnt = 0;
320 	AFFS_I(inode)->i_lc = NULL;
321 	AFFS_I(inode)->i_lc_size = 0;
322 	AFFS_I(inode)->i_lc_shift = 0;
323 	AFFS_I(inode)->i_lc_mask = 0;
324 	AFFS_I(inode)->i_ac = NULL;
325 	AFFS_I(inode)->i_ext_bh = NULL;
326 	AFFS_I(inode)->mmu_private = 0;
327 	AFFS_I(inode)->i_protect = 0;
328 	AFFS_I(inode)->i_lastalloc = 0;
329 	AFFS_I(inode)->i_pa_cnt = 0;
330 	AFFS_I(inode)->i_extcnt = 1;
331 	AFFS_I(inode)->i_ext_last = ~1;
332 
333 	insert_inode_hash(inode);
334 
335 	return inode;
336 
337 err_bh:
338 	affs_free_block(sb, block);
339 err_block:
340 	iput(inode);
341 err_inode:
342 	return NULL;
343 }
344 
345 /*
346  * Add an entry to a directory. Create the header block
347  * and insert it into the hash table.
348  */
349 
350 int
351 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
352 {
353 	struct super_block *sb = dir->i_sb;
354 	struct buffer_head *inode_bh = NULL;
355 	struct buffer_head *bh;
356 	u32 block = 0;
357 	int retval;
358 
359 	pr_debug("%s(dir=%lu, inode=%lu, \"%pd\", type=%d)\n", __func__,
360 		 dir->i_ino, inode->i_ino, dentry, type);
361 
362 	retval = -EIO;
363 	bh = affs_bread(sb, inode->i_ino);
364 	if (!bh)
365 		goto done;
366 
367 	affs_lock_link(inode);
368 	switch (type) {
369 	case ST_LINKFILE:
370 	case ST_LINKDIR:
371 		retval = -ENOSPC;
372 		block = affs_alloc_block(dir, dir->i_ino);
373 		if (!block)
374 			goto err;
375 		retval = -EIO;
376 		inode_bh = bh;
377 		bh = affs_getzeroblk(sb, block);
378 		if (!bh)
379 			goto err;
380 		break;
381 	default:
382 		break;
383 	}
384 
385 	AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
386 	AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
387 	affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
388 	AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
389 	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
390 
391 	if (inode_bh) {
392 		__be32 chain;
393 	       	chain = AFFS_TAIL(sb, inode_bh)->link_chain;
394 		AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
395 		AFFS_TAIL(sb, bh)->link_chain = chain;
396 		AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
397 		affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
398 		mark_buffer_dirty_inode(inode_bh, inode);
399 		set_nlink(inode, 2);
400 		ihold(inode);
401 	}
402 	affs_fix_checksum(sb, bh);
403 	mark_buffer_dirty_inode(bh, inode);
404 	dentry->d_fsdata = (void *)(long)bh->b_blocknr;
405 
406 	affs_lock_dir(dir);
407 	retval = affs_insert_hash(dir, bh);
408 	mark_buffer_dirty_inode(bh, inode);
409 	affs_unlock_dir(dir);
410 	affs_unlock_link(inode);
411 
412 	d_instantiate(dentry, inode);
413 done:
414 	affs_brelse(inode_bh);
415 	affs_brelse(bh);
416 	return retval;
417 err:
418 	if (block)
419 		affs_free_block(sb, block);
420 	affs_unlock_link(inode);
421 	goto done;
422 }
423