1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * linux/fs/ufs/ialloc.c |
4 | * |
5 | * Copyright (c) 1998 |
6 | * Daniel Pirkl <daniel.pirkl@email.cz> |
7 | * Charles University, Faculty of Mathematics and Physics |
8 | * |
9 | * from |
10 | * |
11 | * linux/fs/ext2/ialloc.c |
12 | * |
13 | * Copyright (C) 1992, 1993, 1994, 1995 |
14 | * Remy Card (card@masi.ibp.fr) |
15 | * Laboratoire MASI - Institut Blaise Pascal |
16 | * Universite Pierre et Marie Curie (Paris VI) |
17 | * |
18 | * BSD ufs-inspired inode and directory allocation by |
19 | * Stephen Tweedie (sct@dcs.ed.ac.uk), 1993 |
20 | * Big-endian to little-endian byte-swapping/bitmaps by |
21 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
22 | * |
23 | * UFS2 write support added by |
24 | * Evgeniy Dushistov <dushistov@mail.ru>, 2007 |
25 | */ |
26 | |
27 | #include <linux/fs.h> |
28 | #include <linux/time.h> |
29 | #include <linux/stat.h> |
30 | #include <linux/string.h> |
31 | #include <linux/buffer_head.h> |
32 | #include <linux/sched.h> |
33 | #include <linux/bitops.h> |
34 | #include <asm/byteorder.h> |
35 | |
36 | #include "ufs_fs.h" |
37 | #include "ufs.h" |
38 | #include "swab.h" |
39 | #include "util.h" |
40 | |
41 | /* |
42 | * NOTE! When we get the inode, we're the only people |
43 | * that have access to it, and as such there are no |
44 | * race conditions we have to worry about. The inode |
45 | * is not on the hash-lists, and it cannot be reached |
46 | * through the filesystem because the directory entry |
47 | * has been deleted earlier. |
48 | * |
49 | * HOWEVER: we must make sure that we get no aliases, |
50 | * which means that we have to call "clear_inode()" |
51 | * _before_ we mark the inode not in use in the inode |
52 | * bitmaps. Otherwise a newly created file might use |
53 | * the same inode number (not actually the same pointer |
54 | * though), and then we'd have two inodes sharing the |
55 | * same inode number and space on the harddisk. |
56 | */ |
57 | void ufs_free_inode (struct inode * inode) |
58 | { |
59 | struct super_block * sb; |
60 | struct ufs_sb_private_info * uspi; |
61 | struct ufs_cg_private_info * ucpi; |
62 | struct ufs_cylinder_group * ucg; |
63 | int is_directory; |
64 | unsigned ino, cg, bit; |
65 | |
66 | UFSD("ENTER, ino %lu\n" , inode->i_ino); |
67 | |
68 | sb = inode->i_sb; |
69 | uspi = UFS_SB(sb)->s_uspi; |
70 | |
71 | ino = inode->i_ino; |
72 | |
73 | mutex_lock(&UFS_SB(sb)->s_lock); |
74 | |
75 | if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) { |
76 | ufs_warning(sb, "ufs_free_inode" , "reserved inode or nonexistent inode %u\n" , ino); |
77 | mutex_unlock(lock: &UFS_SB(sb)->s_lock); |
78 | return; |
79 | } |
80 | |
81 | cg = ufs_inotocg (ino); |
82 | bit = ufs_inotocgoff (ino); |
83 | ucpi = ufs_load_cylinder (sb, cg); |
84 | if (!ucpi) { |
85 | mutex_unlock(lock: &UFS_SB(sb)->s_lock); |
86 | return; |
87 | } |
88 | ucg = ubh_get_ucg(UCPI_UBH(ucpi)); |
89 | if (!ufs_cg_chkmagic(sb, ucg)) |
90 | ufs_panic (sb, "ufs_free_fragments" , "internal error, bad cg magic number" ); |
91 | |
92 | ucg->cg_time = ufs_get_seconds(sbp: sb); |
93 | |
94 | is_directory = S_ISDIR(inode->i_mode); |
95 | |
96 | if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) |
97 | ufs_error(sb, "ufs_free_inode" , "bit already cleared for inode %u" , ino); |
98 | else { |
99 | ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); |
100 | if (ino < ucpi->c_irotor) |
101 | ucpi->c_irotor = ino; |
102 | fs32_add(sbp: sb, n: &ucg->cg_cs.cs_nifree, d: 1); |
103 | uspi->cs_total.cs_nifree++; |
104 | fs32_add(sbp: sb, n: &UFS_SB(sb)->fs_cs(cg).cs_nifree, d: 1); |
105 | |
106 | if (is_directory) { |
107 | fs32_sub(sbp: sb, n: &ucg->cg_cs.cs_ndir, d: 1); |
108 | uspi->cs_total.cs_ndir--; |
109 | fs32_sub(sbp: sb, n: &UFS_SB(sb)->fs_cs(cg).cs_ndir, d: 1); |
110 | } |
111 | } |
112 | |
113 | ubh_mark_buffer_dirty (USPI_UBH(spi: uspi)); |
114 | ubh_mark_buffer_dirty (UCPI_UBH(cpi: ucpi)); |
115 | if (sb->s_flags & SB_SYNCHRONOUS) |
116 | ubh_sync_block(UCPI_UBH(cpi: ucpi)); |
117 | |
118 | ufs_mark_sb_dirty(sb); |
119 | mutex_unlock(lock: &UFS_SB(sb)->s_lock); |
120 | UFSD("EXIT\n" ); |
121 | } |
122 | |
123 | /* |
124 | * Nullify new chunk of inodes, |
125 | * BSD people also set ui_gen field of inode |
126 | * during nullification, but we not care about |
127 | * that because of linux ufs do not support NFS |
128 | */ |
129 | static void ufs2_init_inodes_chunk(struct super_block *sb, |
130 | struct ufs_cg_private_info *ucpi, |
131 | struct ufs_cylinder_group *ucg) |
132 | { |
133 | struct buffer_head *bh; |
134 | struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi; |
135 | sector_t beg = uspi->s_sbbase + |
136 | ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg + |
137 | fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk)); |
138 | sector_t end = beg + uspi->s_fpb; |
139 | |
140 | UFSD("ENTER cgno %d\n" , ucpi->c_cgx); |
141 | |
142 | for (; beg < end; ++beg) { |
143 | bh = sb_getblk(sb, block: beg); |
144 | lock_buffer(bh); |
145 | memset(bh->b_data, 0, sb->s_blocksize); |
146 | set_buffer_uptodate(bh); |
147 | mark_buffer_dirty(bh); |
148 | unlock_buffer(bh); |
149 | if (sb->s_flags & SB_SYNCHRONOUS) |
150 | sync_dirty_buffer(bh); |
151 | brelse(bh); |
152 | } |
153 | |
154 | fs32_add(sbp: sb, n: &ucg->cg_u.cg_u2.cg_initediblk, d: uspi->s_inopb); |
155 | ubh_mark_buffer_dirty(UCPI_UBH(cpi: ucpi)); |
156 | if (sb->s_flags & SB_SYNCHRONOUS) |
157 | ubh_sync_block(UCPI_UBH(cpi: ucpi)); |
158 | |
159 | UFSD("EXIT\n" ); |
160 | } |
161 | |
162 | /* |
163 | * There are two policies for allocating an inode. If the new inode is |
164 | * a directory, then a forward search is made for a block group with both |
165 | * free space and a low directory-to-inode ratio; if that fails, then of |
166 | * the groups with above-average free space, that group with the fewest |
167 | * directories already is chosen. |
168 | * |
169 | * For other inodes, search forward from the parent directory's block |
170 | * group to find a free inode. |
171 | */ |
172 | struct inode *ufs_new_inode(struct inode *dir, umode_t mode) |
173 | { |
174 | struct super_block * sb; |
175 | struct ufs_sb_info * sbi; |
176 | struct ufs_sb_private_info * uspi; |
177 | struct ufs_cg_private_info * ucpi; |
178 | struct ufs_cylinder_group * ucg; |
179 | struct inode * inode; |
180 | struct timespec64 ts; |
181 | unsigned cg, bit, i, j, start; |
182 | struct ufs_inode_info *ufsi; |
183 | int err = -ENOSPC; |
184 | |
185 | UFSD("ENTER\n" ); |
186 | |
187 | /* Cannot create files in a deleted directory */ |
188 | if (!dir || !dir->i_nlink) |
189 | return ERR_PTR(error: -EPERM); |
190 | sb = dir->i_sb; |
191 | inode = new_inode(sb); |
192 | if (!inode) |
193 | return ERR_PTR(error: -ENOMEM); |
194 | ufsi = UFS_I(inode); |
195 | sbi = UFS_SB(sb); |
196 | uspi = sbi->s_uspi; |
197 | |
198 | mutex_lock(&sbi->s_lock); |
199 | |
200 | /* |
201 | * Try to place the inode in its parent directory |
202 | */ |
203 | i = ufs_inotocg(dir->i_ino); |
204 | if (sbi->fs_cs(i).cs_nifree) { |
205 | cg = i; |
206 | goto cg_found; |
207 | } |
208 | |
209 | /* |
210 | * Use a quadratic hash to find a group with a free inode |
211 | */ |
212 | for ( j = 1; j < uspi->s_ncg; j <<= 1 ) { |
213 | i += j; |
214 | if (i >= uspi->s_ncg) |
215 | i -= uspi->s_ncg; |
216 | if (sbi->fs_cs(i).cs_nifree) { |
217 | cg = i; |
218 | goto cg_found; |
219 | } |
220 | } |
221 | |
222 | /* |
223 | * That failed: try linear search for a free inode |
224 | */ |
225 | i = ufs_inotocg(dir->i_ino) + 1; |
226 | for (j = 2; j < uspi->s_ncg; j++) { |
227 | i++; |
228 | if (i >= uspi->s_ncg) |
229 | i = 0; |
230 | if (sbi->fs_cs(i).cs_nifree) { |
231 | cg = i; |
232 | goto cg_found; |
233 | } |
234 | } |
235 | |
236 | goto failed; |
237 | |
238 | cg_found: |
239 | ucpi = ufs_load_cylinder (sb, cg); |
240 | if (!ucpi) { |
241 | err = -EIO; |
242 | goto failed; |
243 | } |
244 | ucg = ubh_get_ucg(UCPI_UBH(ucpi)); |
245 | if (!ufs_cg_chkmagic(sb, ucg)) |
246 | ufs_panic (sb, "ufs_new_inode" , "internal error, bad cg magic number" ); |
247 | |
248 | start = ucpi->c_irotor; |
249 | bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start); |
250 | if (!(bit < uspi->s_ipg)) { |
251 | bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start); |
252 | if (!(bit < start)) { |
253 | ufs_error (sb, "ufs_new_inode" , |
254 | "cylinder group %u corrupted - error in inode bitmap\n" , cg); |
255 | err = -EIO; |
256 | goto failed; |
257 | } |
258 | } |
259 | UFSD("start = %u, bit = %u, ipg = %u\n" , start, bit, uspi->s_ipg); |
260 | if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit)) |
261 | ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit); |
262 | else { |
263 | ufs_panic (sb, "ufs_new_inode" , "internal error" ); |
264 | err = -EIO; |
265 | goto failed; |
266 | } |
267 | |
268 | if (uspi->fs_magic == UFS2_MAGIC) { |
269 | u32 initediblk = fs32_to_cpu(sbp: sb, n: ucg->cg_u.cg_u2.cg_initediblk); |
270 | |
271 | if (bit + uspi->s_inopb > initediblk && |
272 | initediblk < fs32_to_cpu(sbp: sb, n: ucg->cg_u.cg_u2.cg_niblk)) |
273 | ufs2_init_inodes_chunk(sb, ucpi, ucg); |
274 | } |
275 | |
276 | fs32_sub(sbp: sb, n: &ucg->cg_cs.cs_nifree, d: 1); |
277 | uspi->cs_total.cs_nifree--; |
278 | fs32_sub(sbp: sb, n: &sbi->fs_cs(cg).cs_nifree, d: 1); |
279 | |
280 | if (S_ISDIR(mode)) { |
281 | fs32_add(sbp: sb, n: &ucg->cg_cs.cs_ndir, d: 1); |
282 | uspi->cs_total.cs_ndir++; |
283 | fs32_add(sbp: sb, n: &sbi->fs_cs(cg).cs_ndir, d: 1); |
284 | } |
285 | ubh_mark_buffer_dirty (USPI_UBH(spi: uspi)); |
286 | ubh_mark_buffer_dirty (UCPI_UBH(cpi: ucpi)); |
287 | if (sb->s_flags & SB_SYNCHRONOUS) |
288 | ubh_sync_block(UCPI_UBH(cpi: ucpi)); |
289 | ufs_mark_sb_dirty(sb); |
290 | |
291 | inode->i_ino = cg * uspi->s_ipg + bit; |
292 | inode_init_owner(idmap: &nop_mnt_idmap, inode, dir, mode); |
293 | inode->i_blocks = 0; |
294 | inode->i_generation = 0; |
295 | simple_inode_init_ts(inode); |
296 | ufsi->i_flags = UFS_I(inode: dir)->i_flags; |
297 | ufsi->i_lastfrag = 0; |
298 | ufsi->i_shadow = 0; |
299 | ufsi->i_osync = 0; |
300 | ufsi->i_oeftflag = 0; |
301 | ufsi->i_dir_start_lookup = 0; |
302 | memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1)); |
303 | if (insert_inode_locked(inode) < 0) { |
304 | err = -EIO; |
305 | goto failed; |
306 | } |
307 | mark_inode_dirty(inode); |
308 | |
309 | if (uspi->fs_magic == UFS2_MAGIC) { |
310 | struct buffer_head *bh; |
311 | struct ufs2_inode *ufs2_inode; |
312 | |
313 | /* |
314 | * setup birth date, we do it here because of there is no sense |
315 | * to hold it in struct ufs_inode_info, and lose 64 bit |
316 | */ |
317 | bh = sb_bread(sb, block: uspi->s_sbbase + ufs_inotofsba(inode->i_ino)); |
318 | if (!bh) { |
319 | ufs_warning(sb, "ufs_read_inode" , |
320 | "unable to read inode %lu\n" , |
321 | inode->i_ino); |
322 | err = -EIO; |
323 | goto fail_remove_inode; |
324 | } |
325 | lock_buffer(bh); |
326 | ufs2_inode = (struct ufs2_inode *)bh->b_data; |
327 | ufs2_inode += ufs_inotofsbo(inode->i_ino); |
328 | ktime_get_real_ts64(tv: &ts); |
329 | ufs2_inode->ui_birthtime = cpu_to_fs64(sbp: sb, n: ts.tv_sec); |
330 | ufs2_inode->ui_birthnsec = cpu_to_fs32(sbp: sb, n: ts.tv_nsec); |
331 | mark_buffer_dirty(bh); |
332 | unlock_buffer(bh); |
333 | if (sb->s_flags & SB_SYNCHRONOUS) |
334 | sync_dirty_buffer(bh); |
335 | brelse(bh); |
336 | } |
337 | mutex_unlock(lock: &sbi->s_lock); |
338 | |
339 | UFSD("allocating inode %lu\n" , inode->i_ino); |
340 | UFSD("EXIT\n" ); |
341 | return inode; |
342 | |
343 | fail_remove_inode: |
344 | mutex_unlock(lock: &sbi->s_lock); |
345 | clear_nlink(inode); |
346 | discard_new_inode(inode); |
347 | UFSD("EXIT (FAILED): err %d\n" , err); |
348 | return ERR_PTR(error: err); |
349 | failed: |
350 | mutex_unlock(lock: &sbi->s_lock); |
351 | make_bad_inode(inode); |
352 | iput (inode); |
353 | UFSD("EXIT (FAILED): err %d\n" , err); |
354 | return ERR_PTR(error: err); |
355 | } |
356 | |