xref: /kernel/linux/linux-6.6/fs/affs/inode.c (revision 62306a36)
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
18struct 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 =
153		inode_set_ctime(inode,
154				(be32_to_cpu(tail->change.days) * 86400LL +
155				 be32_to_cpu(tail->change.mins) * 60 +
156				 be32_to_cpu(tail->change.ticks) / 50 + AFFS_EPOCH_DELTA)
157				+ sys_tz.tz_minuteswest * 60, 0).tv_sec;
158	inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = 0;
159	affs_brelse(bh);
160	unlock_new_inode(inode);
161	return inode;
162
163bad_inode:
164	affs_brelse(bh);
165	iget_failed(inode);
166	return ERR_PTR(-EIO);
167}
168
169int
170affs_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
218int
219affs_notify_change(struct mnt_idmap *idmap, 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(&nop_mnt_idmap, 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(&nop_mnt_idmap, inode, attr);
254	mark_inode_dirty(inode);
255
256	if (attr->ia_valid & ATTR_MODE)
257		affs_mode_to_prot(inode);
258out:
259	return error;
260}
261
262void
263affs_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
293struct inode *
294affs_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_set_ctime_current(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
337err_bh:
338	affs_free_block(sb, block);
339err_block:
340	iput(inode);
341err_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
350int
351affs_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);
413done:
414	affs_brelse(inode_bh);
415	affs_brelse(bh);
416	return retval;
417err:
418	if (block)
419		affs_free_block(sb, block);
420	affs_unlock_link(inode);
421	goto done;
422}
423