1 | /* $NetBSD: ext2fs_alloc.c,v 1.51 2016/08/20 19:53:43 jdolecek Exp $ */ |
2 | |
3 | /* |
4 | * Copyright (c) 1982, 1986, 1989, 1993 |
5 | * The Regents of the University of California. All rights reserved. |
6 | * |
7 | * Redistribution and use in source and binary forms, with or without |
8 | * modification, are permitted provided that the following conditions |
9 | * are met: |
10 | * 1. Redistributions of source code must retain the above copyright |
11 | * notice, this list of conditions and the following disclaimer. |
12 | * 2. Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * 3. Neither the name of the University nor the names of its contributors |
16 | * may be used to endorse or promote products derived from this software |
17 | * without specific prior written permission. |
18 | * |
19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
29 | * SUCH DAMAGE. |
30 | * |
31 | * @(#)ffs_alloc.c 8.11 (Berkeley) 10/27/94 |
32 | * Modified for ext2fs by Manuel Bouyer. |
33 | */ |
34 | |
35 | /* |
36 | * Copyright (c) 1997 Manuel Bouyer. |
37 | * |
38 | * Redistribution and use in source and binary forms, with or without |
39 | * modification, are permitted provided that the following conditions |
40 | * are met: |
41 | * 1. Redistributions of source code must retain the above copyright |
42 | * notice, this list of conditions and the following disclaimer. |
43 | * 2. Redistributions in binary form must reproduce the above copyright |
44 | * notice, this list of conditions and the following disclaimer in the |
45 | * documentation and/or other materials provided with the distribution. |
46 | * |
47 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
48 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
49 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
50 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
51 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
52 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
53 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
54 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
55 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
56 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
57 | * |
58 | * @(#)ffs_alloc.c 8.11 (Berkeley) 10/27/94 |
59 | * Modified for ext2fs by Manuel Bouyer. |
60 | */ |
61 | |
62 | #include <sys/cdefs.h> |
63 | __KERNEL_RCSID(0, "$NetBSD: ext2fs_alloc.c,v 1.51 2016/08/20 19:53:43 jdolecek Exp $" ); |
64 | |
65 | #include <sys/param.h> |
66 | #include <sys/systm.h> |
67 | #include <sys/buf.h> |
68 | #include <sys/proc.h> |
69 | #include <sys/vnode.h> |
70 | #include <sys/mount.h> |
71 | #include <sys/kernel.h> |
72 | #include <sys/syslog.h> |
73 | #include <sys/kauth.h> |
74 | |
75 | #include <lib/libkern/crc16.h> |
76 | |
77 | #include <ufs/ufs/inode.h> |
78 | #include <ufs/ufs/ufs_extern.h> |
79 | #include <ufs/ufs/ufsmount.h> |
80 | |
81 | #include <ufs/ext2fs/ext2fs.h> |
82 | #include <ufs/ext2fs/ext2fs_extern.h> |
83 | |
84 | u_long ext2gennumber; |
85 | |
86 | static daddr_t ext2fs_alloccg(struct inode *, int, daddr_t, int); |
87 | static u_long ext2fs_dirpref(struct m_ext2fs *); |
88 | static void ext2fs_fserr(struct m_ext2fs *, u_int, const char *); |
89 | static u_long ext2fs_hashalloc(struct inode *, int, long, int, |
90 | daddr_t (*)(struct inode *, int, daddr_t, int)); |
91 | static daddr_t ext2fs_nodealloccg(struct inode *, int, daddr_t, int); |
92 | static daddr_t ext2fs_mapsearch(struct m_ext2fs *, char *, daddr_t); |
93 | static __inline void ext2fs_cg_update(struct m_ext2fs *, int, struct ext2_gd *, int, int, int, daddr_t); |
94 | static uint16_t ext2fs_cg_get_csum(struct m_ext2fs *, int, struct ext2_gd *); |
95 | static void ext2fs_init_bb(struct m_ext2fs *, int, struct ext2_gd *, char *); |
96 | |
97 | /* |
98 | * Allocate a block in the file system. |
99 | * |
100 | * A preference may be optionally specified. If a preference is given |
101 | * the following hierarchy is used to allocate a block: |
102 | * 1) allocate the requested block. |
103 | * 2) allocate a rotationally optimal block in the same cylinder. |
104 | * 3) allocate a block in the same cylinder group. |
105 | * 4) quadradically rehash into other cylinder groups, until an |
106 | * available block is located. |
107 | * If no block preference is given the following hierarchy is used |
108 | * to allocate a block: |
109 | * 1) allocate a block in the cylinder group that contains the |
110 | * inode for the file. |
111 | * 2) quadradically rehash into other cylinder groups, until an |
112 | * available block is located. |
113 | */ |
114 | int |
115 | ext2fs_alloc(struct inode *ip, daddr_t lbn, daddr_t bpref, |
116 | kauth_cred_t cred, daddr_t *bnp) |
117 | { |
118 | struct m_ext2fs *fs; |
119 | daddr_t bno; |
120 | int cg; |
121 | |
122 | *bnp = 0; |
123 | fs = ip->i_e2fs; |
124 | #ifdef DIAGNOSTIC |
125 | if (cred == NOCRED) |
126 | panic("ext2fs_alloc: missing credential" ); |
127 | #endif /* DIAGNOSTIC */ |
128 | if (fs->e2fs.e2fs_fbcount == 0) |
129 | goto nospace; |
130 | if (kauth_authorize_system(cred, KAUTH_SYSTEM_FS_RESERVEDSPACE, 0, NULL, |
131 | NULL, NULL) != 0 && |
132 | freespace(fs) <= 0) |
133 | goto nospace; |
134 | if (bpref >= fs->e2fs.e2fs_bcount) |
135 | bpref = 0; |
136 | if (bpref == 0) |
137 | cg = ino_to_cg(fs, ip->i_number); |
138 | else |
139 | cg = dtog(fs, bpref); |
140 | bno = (daddr_t)ext2fs_hashalloc(ip, cg, bpref, fs->e2fs_bsize, |
141 | ext2fs_alloccg); |
142 | if (bno > 0) { |
143 | ext2fs_setnblock(ip, ext2fs_nblock(ip) + btodb(fs->e2fs_bsize)); |
144 | ip->i_flag |= IN_CHANGE | IN_UPDATE; |
145 | *bnp = bno; |
146 | return 0; |
147 | } |
148 | nospace: |
149 | ext2fs_fserr(fs, kauth_cred_geteuid(cred), "file system full" ); |
150 | uprintf("\n%s: write failed, file system is full\n" , fs->e2fs_fsmnt); |
151 | return ENOSPC; |
152 | } |
153 | |
154 | /* |
155 | * Allocate an inode in the file system. |
156 | * |
157 | * If allocating a directory, use ext2fs_dirpref to select the inode. |
158 | * If allocating in a directory, the following hierarchy is followed: |
159 | * 1) allocate the preferred inode. |
160 | * 2) allocate an inode in the same cylinder group. |
161 | * 3) quadradically rehash into other cylinder groups, until an |
162 | * available inode is located. |
163 | * If no inode preference is given the following hierarchy is used |
164 | * to allocate an inode: |
165 | * 1) allocate an inode in cylinder group 0. |
166 | * 2) quadradically rehash into other cylinder groups, until an |
167 | * available inode is located. |
168 | */ |
169 | int |
170 | ext2fs_valloc(struct vnode *pvp, int mode, kauth_cred_t cred, |
171 | struct vnode **vpp) |
172 | { |
173 | struct inode *pip; |
174 | struct m_ext2fs *fs; |
175 | struct inode *ip; |
176 | ino_t ino, ipref; |
177 | int cg, error; |
178 | |
179 | *vpp = NULL; |
180 | pip = VTOI(pvp); |
181 | fs = pip->i_e2fs; |
182 | if (fs->e2fs.e2fs_ficount == 0) |
183 | goto noinodes; |
184 | |
185 | if ((mode & IFMT) == IFDIR) |
186 | cg = ext2fs_dirpref(fs); |
187 | else |
188 | cg = ino_to_cg(fs, pip->i_number); |
189 | ipref = cg * fs->e2fs.e2fs_ipg + 1; |
190 | ino = (ino_t)ext2fs_hashalloc(pip, cg, (long)ipref, mode, ext2fs_nodealloccg); |
191 | if (ino == 0) |
192 | goto noinodes; |
193 | error = VFS_VGET(pvp->v_mount, ino, vpp); |
194 | if (error) { |
195 | ext2fs_vfree(pvp, ino, mode); |
196 | return error; |
197 | } |
198 | ip = VTOI(*vpp); |
199 | |
200 | KASSERT(!E2FS_HAS_GD_CSUM(fs) || (fs->e2fs_gd[ino_to_cg(fs, ino)].ext2bgd_flags & h2fs16(E2FS_BG_INODE_ZEROED)) != 0); |
201 | |
202 | /* check for already used inode; makes sense only for ZEROED itable */ |
203 | if (__predict_false(ip->i_e2fs_mode && ip->i_e2fs_nlink != 0)) { |
204 | printf("mode = 0%o, nlinks %d, inum = %llu, fs = %s\n" , |
205 | ip->i_e2fs_mode, ip->i_e2fs_nlink, |
206 | (unsigned long long)ip->i_number, fs->e2fs_fsmnt); |
207 | panic("ext2fs_valloc: dup alloc" ); |
208 | } |
209 | |
210 | memset(ip->i_din.e2fs_din, 0, EXT2_DINODE_SIZE(fs)); |
211 | |
212 | /* |
213 | * Set up a new generation number for this inode. |
214 | */ |
215 | if (++ext2gennumber < time_second) |
216 | ext2gennumber = time_second; |
217 | ip->i_e2fs_gen = ext2gennumber; |
218 | return 0; |
219 | noinodes: |
220 | ext2fs_fserr(fs, kauth_cred_geteuid(cred), "out of inodes" ); |
221 | uprintf("\n%s: create/symlink failed, no inodes free\n" , fs->e2fs_fsmnt); |
222 | return ENOSPC; |
223 | } |
224 | |
225 | /* |
226 | * Find a cylinder to place a directory. |
227 | * |
228 | * The policy implemented by this algorithm is to select from |
229 | * among those cylinder groups with above the average number of |
230 | * free inodes, the one with the smallest number of directories. |
231 | */ |
232 | static u_long |
233 | ext2fs_dirpref(struct m_ext2fs *fs) |
234 | { |
235 | int cg, maxspace, mincg, avgifree; |
236 | |
237 | avgifree = fs->e2fs.e2fs_ficount / fs->e2fs_ncg; |
238 | maxspace = 0; |
239 | mincg = -1; |
240 | for (cg = 0; cg < fs->e2fs_ncg; cg++) |
241 | if (fs2h16(fs->e2fs_gd[cg].ext2bgd_nifree) >= avgifree) { |
242 | if (mincg == -1 || fs2h16(fs->e2fs_gd[cg].ext2bgd_nbfree) > maxspace) { |
243 | mincg = cg; |
244 | maxspace = fs2h16(fs->e2fs_gd[cg].ext2bgd_nbfree); |
245 | } |
246 | } |
247 | return mincg; |
248 | } |
249 | |
250 | /* |
251 | * Select the desired position for the next block in a file. The file is |
252 | * logically divided into sections. The first section is composed of the |
253 | * direct blocks. Each additional section contains fs_maxbpg blocks. |
254 | * |
255 | * If no blocks have been allocated in the first section, the policy is to |
256 | * request a block in the same cylinder group as the inode that describes |
257 | * the file. Otherwise, the policy is to try to allocate the blocks |
258 | * contigously. The two fields of the ext2 inode extension (see |
259 | * ufs/ufs/inode.h) help this. |
260 | */ |
261 | daddr_t |
262 | ext2fs_blkpref(struct inode *ip, daddr_t lbn, int indx, |
263 | int32_t *bap /* XXX ondisk32 */) |
264 | { |
265 | struct m_ext2fs *fs; |
266 | int cg, i; |
267 | |
268 | fs = ip->i_e2fs; |
269 | /* |
270 | * if we are doing contigous lbn allocation, try to alloc blocks |
271 | * contigously on disk |
272 | */ |
273 | |
274 | if ( ip->i_e2fs_last_blk && lbn == ip->i_e2fs_last_lblk + 1) { |
275 | return ip->i_e2fs_last_blk + 1; |
276 | } |
277 | |
278 | /* |
279 | * bap, if provided, gives us a list of blocks to which we want to |
280 | * stay close |
281 | */ |
282 | |
283 | if (bap) { |
284 | for (i = indx; i >= 0 ; i--) { |
285 | if (bap[i]) { |
286 | return fs2h32(bap[i]) + 1; |
287 | } |
288 | } |
289 | } |
290 | |
291 | /* fall back to the first block of the cylinder containing the inode */ |
292 | |
293 | cg = ino_to_cg(fs, ip->i_number); |
294 | return fs->e2fs.e2fs_bpg * cg + fs->e2fs.e2fs_first_dblock + 1; |
295 | } |
296 | |
297 | /* |
298 | * Implement the cylinder overflow algorithm. |
299 | * |
300 | * The policy implemented by this algorithm is: |
301 | * 1) allocate the block in its requested cylinder group. |
302 | * 2) quadradically rehash on the cylinder group number. |
303 | * 3) brute force search for a free block. |
304 | */ |
305 | static u_long |
306 | ext2fs_hashalloc(struct inode *ip, int cg, long pref, int size, |
307 | daddr_t (*allocator)(struct inode *, int, daddr_t, int)) |
308 | { |
309 | struct m_ext2fs *fs; |
310 | long result; |
311 | int i, icg = cg; |
312 | |
313 | fs = ip->i_e2fs; |
314 | /* |
315 | * 1: preferred cylinder group |
316 | */ |
317 | result = (*allocator)(ip, cg, pref, size); |
318 | if (result) |
319 | return result; |
320 | /* |
321 | * 2: quadratic rehash |
322 | */ |
323 | for (i = 1; i < fs->e2fs_ncg; i *= 2) { |
324 | cg += i; |
325 | if (cg >= fs->e2fs_ncg) |
326 | cg -= fs->e2fs_ncg; |
327 | result = (*allocator)(ip, cg, 0, size); |
328 | if (result) |
329 | return result; |
330 | } |
331 | /* |
332 | * 3: brute force search |
333 | * Note that we start at i == 2, since 0 was checked initially, |
334 | * and 1 is always checked in the quadratic rehash. |
335 | */ |
336 | cg = (icg + 2) % fs->e2fs_ncg; |
337 | for (i = 2; i < fs->e2fs_ncg; i++) { |
338 | result = (*allocator)(ip, cg, 0, size); |
339 | if (result) |
340 | return result; |
341 | cg++; |
342 | if (cg == fs->e2fs_ncg) |
343 | cg = 0; |
344 | } |
345 | return 0; |
346 | } |
347 | |
348 | /* |
349 | * Determine whether a block can be allocated. |
350 | * |
351 | * Check to see if a block of the appropriate size is available, |
352 | * and if it is, allocate it. |
353 | */ |
354 | |
355 | static daddr_t |
356 | ext2fs_alloccg(struct inode *ip, int cg, daddr_t bpref, int size) |
357 | { |
358 | struct m_ext2fs *fs; |
359 | char *bbp; |
360 | struct buf *bp; |
361 | /* XXX ondisk32 */ |
362 | int error, bno, start, end, loc; |
363 | |
364 | fs = ip->i_e2fs; |
365 | if (fs->e2fs_gd[cg].ext2bgd_nbfree == 0) |
366 | return 0; |
367 | error = bread(ip->i_devvp, EXT2_FSBTODB(fs, |
368 | fs2h32(fs->e2fs_gd[cg].ext2bgd_b_bitmap)), |
369 | (int)fs->e2fs_bsize, B_MODIFY, &bp); |
370 | if (error) { |
371 | return 0; |
372 | } |
373 | bbp = (char *)bp->b_data; |
374 | |
375 | if (dtog(fs, bpref) != cg) |
376 | bpref = 0; |
377 | |
378 | /* initialize block bitmap now if uninit */ |
379 | if (__predict_false(E2FS_HAS_GD_CSUM(fs) && |
380 | (fs->e2fs_gd[cg].ext2bgd_flags & h2fs16(E2FS_BG_BLOCK_UNINIT)))) { |
381 | ext2fs_init_bb(fs, cg, &fs->e2fs_gd[cg], bbp); |
382 | fs->e2fs_gd[cg].ext2bgd_flags &= h2fs16(~E2FS_BG_BLOCK_UNINIT); |
383 | } |
384 | |
385 | if (bpref != 0) { |
386 | bpref = dtogd(fs, bpref); |
387 | /* |
388 | * if the requested block is available, use it |
389 | */ |
390 | if (isclr(bbp, bpref)) { |
391 | bno = bpref; |
392 | goto gotit; |
393 | } |
394 | } |
395 | /* |
396 | * no blocks in the requested cylinder, so take next |
397 | * available one in this cylinder group. |
398 | * first try to get 8 contigous blocks, then fall back to a single |
399 | * block. |
400 | */ |
401 | if (bpref) |
402 | start = dtogd(fs, bpref) / NBBY; |
403 | else |
404 | start = 0; |
405 | end = howmany(fs->e2fs.e2fs_fpg, NBBY) - start; |
406 | for (loc = start; loc < end; loc++) { |
407 | if (bbp[loc] == 0) { |
408 | bno = loc * NBBY; |
409 | goto gotit; |
410 | } |
411 | } |
412 | for (loc = 0; loc < start; loc++) { |
413 | if (bbp[loc] == 0) { |
414 | bno = loc * NBBY; |
415 | goto gotit; |
416 | } |
417 | } |
418 | |
419 | bno = ext2fs_mapsearch(fs, bbp, bpref); |
420 | #if 0 |
421 | /* |
422 | * XXX jdolecek mapsearch actually never fails, it panics instead. |
423 | * If re-enabling, make sure to brele() before returning. |
424 | */ |
425 | if (bno < 0) |
426 | return 0; |
427 | #endif |
428 | gotit: |
429 | #ifdef DIAGNOSTIC |
430 | if (isset(bbp, (daddr_t)bno)) { |
431 | printf("ext2fs_alloccgblk: cg=%d bno=%d fs=%s\n" , |
432 | cg, bno, fs->e2fs_fsmnt); |
433 | panic("ext2fs_alloccg: dup alloc" ); |
434 | } |
435 | #endif |
436 | setbit(bbp, (daddr_t)bno); |
437 | fs->e2fs.e2fs_fbcount--; |
438 | ext2fs_cg_update(fs, cg, &fs->e2fs_gd[cg], -1, 0, 0, 0); |
439 | fs->e2fs_fmod = 1; |
440 | bdwrite(bp); |
441 | return cg * fs->e2fs.e2fs_fpg + fs->e2fs.e2fs_first_dblock + bno; |
442 | } |
443 | |
444 | /* |
445 | * Determine whether an inode can be allocated. |
446 | * |
447 | * Check to see if an inode is available, and if it is, |
448 | * allocate it using the following policy: |
449 | * 1) allocate the requested inode. |
450 | * 2) allocate the next available inode after the requested |
451 | * inode in the specified cylinder group. |
452 | */ |
453 | static daddr_t |
454 | ext2fs_nodealloccg(struct inode *ip, int cg, daddr_t ipref, int mode) |
455 | { |
456 | struct m_ext2fs *fs; |
457 | char *ibp; |
458 | struct buf *bp; |
459 | int error, start, len, loc, map, i; |
460 | |
461 | ipref--; /* to avoid a lot of (ipref -1) */ |
462 | if (ipref == -1) |
463 | ipref = 0; |
464 | fs = ip->i_e2fs; |
465 | if (fs->e2fs_gd[cg].ext2bgd_nifree == 0) |
466 | return 0; |
467 | error = bread(ip->i_devvp, EXT2_FSBTODB(fs, |
468 | fs2h32(fs->e2fs_gd[cg].ext2bgd_i_bitmap)), |
469 | (int)fs->e2fs_bsize, B_MODIFY, &bp); |
470 | if (error) { |
471 | return 0; |
472 | } |
473 | ibp = (char *)bp->b_data; |
474 | |
475 | KASSERT(!E2FS_HAS_GD_CSUM(fs) || (fs->e2fs_gd[cg].ext2bgd_flags & h2fs16(E2FS_BG_INODE_ZEROED)) != 0); |
476 | |
477 | /* initialize inode bitmap now if uninit */ |
478 | if (__predict_false(E2FS_HAS_GD_CSUM(fs) && |
479 | (fs->e2fs_gd[cg].ext2bgd_flags & h2fs16(E2FS_BG_INODE_UNINIT)))) { |
480 | KASSERT(fs2h16(fs->e2fs_gd[cg].ext2bgd_nifree) == fs->e2fs.e2fs_ipg); |
481 | memset(ibp, 0, fs->e2fs_bsize); |
482 | fs->e2fs_gd[cg].ext2bgd_flags &= h2fs16(~E2FS_BG_INODE_UNINIT); |
483 | } |
484 | |
485 | if (ipref) { |
486 | ipref %= fs->e2fs.e2fs_ipg; |
487 | if (isclr(ibp, ipref)) |
488 | goto gotit; |
489 | } |
490 | start = ipref / NBBY; |
491 | len = howmany(fs->e2fs.e2fs_ipg - ipref, NBBY); |
492 | loc = skpc(0xff, len, &ibp[start]); |
493 | if (loc == 0) { |
494 | len = start + 1; |
495 | start = 0; |
496 | loc = skpc(0xff, len, &ibp[0]); |
497 | if (loc == 0) { |
498 | printf("cg = %d, ipref = %lld, fs = %s\n" , |
499 | cg, (long long)ipref, fs->e2fs_fsmnt); |
500 | panic("ext2fs_nodealloccg: map corrupted" ); |
501 | /* NOTREACHED */ |
502 | } |
503 | } |
504 | i = start + len - loc; |
505 | map = ibp[i] ^ 0xff; |
506 | if (map == 0) { |
507 | printf("fs = %s\n" , fs->e2fs_fsmnt); |
508 | panic("ext2fs_nodealloccg: inode not in map" ); |
509 | } |
510 | ipref = i * NBBY + ffs(map) - 1; |
511 | gotit: |
512 | setbit(ibp, ipref); |
513 | fs->e2fs.e2fs_ficount--; |
514 | ext2fs_cg_update(fs, cg, &fs->e2fs_gd[cg], |
515 | 0, -1, ((mode & IFMT) == IFDIR) ? 1 : 0, ipref); |
516 | fs->e2fs_fmod = 1; |
517 | bdwrite(bp); |
518 | return cg * fs->e2fs.e2fs_ipg + ipref + 1; |
519 | } |
520 | |
521 | /* |
522 | * Free a block. |
523 | * |
524 | * The specified block is placed back in the |
525 | * free map. |
526 | */ |
527 | void |
528 | ext2fs_blkfree(struct inode *ip, daddr_t bno) |
529 | { |
530 | struct m_ext2fs *fs; |
531 | char *bbp; |
532 | struct buf *bp; |
533 | int error, cg; |
534 | |
535 | fs = ip->i_e2fs; |
536 | cg = dtog(fs, bno); |
537 | |
538 | KASSERT(!E2FS_HAS_GD_CSUM(fs) || (fs->e2fs_gd[cg].ext2bgd_flags & h2fs16(E2FS_BG_BLOCK_UNINIT)) == 0); |
539 | |
540 | if ((u_int)bno >= fs->e2fs.e2fs_bcount) { |
541 | printf("bad block %lld, ino %llu\n" , (long long)bno, |
542 | (unsigned long long)ip->i_number); |
543 | ext2fs_fserr(fs, ip->i_uid, "bad block" ); |
544 | return; |
545 | } |
546 | error = bread(ip->i_devvp, |
547 | EXT2_FSBTODB(fs, fs2h32(fs->e2fs_gd[cg].ext2bgd_b_bitmap)), |
548 | (int)fs->e2fs_bsize, B_MODIFY, &bp); |
549 | if (error) { |
550 | return; |
551 | } |
552 | bbp = (char *)bp->b_data; |
553 | bno = dtogd(fs, bno); |
554 | if (isclr(bbp, bno)) { |
555 | printf("dev = 0x%llx, block = %lld, fs = %s\n" , |
556 | (unsigned long long)ip->i_dev, (long long)bno, |
557 | fs->e2fs_fsmnt); |
558 | panic("blkfree: freeing free block" ); |
559 | } |
560 | clrbit(bbp, bno); |
561 | fs->e2fs.e2fs_fbcount++; |
562 | ext2fs_cg_update(fs, cg, &fs->e2fs_gd[cg], 1, 0, 0, 0); |
563 | fs->e2fs_fmod = 1; |
564 | bdwrite(bp); |
565 | } |
566 | |
567 | /* |
568 | * Free an inode. |
569 | * |
570 | * The specified inode is placed back in the free map. |
571 | */ |
572 | int |
573 | ext2fs_vfree(struct vnode *pvp, ino_t ino, int mode) |
574 | { |
575 | struct m_ext2fs *fs; |
576 | char *ibp; |
577 | struct inode *pip; |
578 | struct buf *bp; |
579 | int error, cg; |
580 | |
581 | pip = VTOI(pvp); |
582 | fs = pip->i_e2fs; |
583 | |
584 | if ((u_int)ino > fs->e2fs.e2fs_icount || (u_int)ino < EXT2_FIRSTINO) |
585 | panic("ifree: range: dev = 0x%llx, ino = %llu, fs = %s" , |
586 | (unsigned long long)pip->i_dev, (unsigned long long)ino, |
587 | fs->e2fs_fsmnt); |
588 | |
589 | cg = ino_to_cg(fs, ino); |
590 | |
591 | KASSERT(!E2FS_HAS_GD_CSUM(fs) || (fs->e2fs_gd[cg].ext2bgd_flags & h2fs16(E2FS_BG_INODE_UNINIT)) == 0); |
592 | |
593 | error = bread(pip->i_devvp, |
594 | EXT2_FSBTODB(fs, fs2h32(fs->e2fs_gd[cg].ext2bgd_i_bitmap)), |
595 | (int)fs->e2fs_bsize, B_MODIFY, &bp); |
596 | if (error) { |
597 | return 0; |
598 | } |
599 | ibp = (char *)bp->b_data; |
600 | ino = (ino - 1) % fs->e2fs.e2fs_ipg; |
601 | if (isclr(ibp, ino)) { |
602 | printf("dev = 0x%llx, ino = %llu, fs = %s\n" , |
603 | (unsigned long long)pip->i_dev, |
604 | (unsigned long long)ino, fs->e2fs_fsmnt); |
605 | if (fs->e2fs_ronly == 0) |
606 | panic("ifree: freeing free inode" ); |
607 | } |
608 | clrbit(ibp, ino); |
609 | fs->e2fs.e2fs_ficount++; |
610 | ext2fs_cg_update(fs, cg, &fs->e2fs_gd[cg], |
611 | 0, 1, ((mode & IFMT) == IFDIR) ? -1 : 0, 0); |
612 | fs->e2fs_fmod = 1; |
613 | bdwrite(bp); |
614 | return 0; |
615 | } |
616 | |
617 | /* |
618 | * Find a block in the specified cylinder group. |
619 | * |
620 | * It is a panic if a request is made to find a block if none are |
621 | * available. |
622 | */ |
623 | |
624 | static daddr_t |
625 | ext2fs_mapsearch(struct m_ext2fs *fs, char *bbp, daddr_t bpref) |
626 | { |
627 | int start, len, loc, i, map; |
628 | |
629 | /* |
630 | * find the fragment by searching through the free block |
631 | * map for an appropriate bit pattern |
632 | */ |
633 | if (bpref) |
634 | start = dtogd(fs, bpref) / NBBY; |
635 | else |
636 | start = 0; |
637 | len = howmany(fs->e2fs.e2fs_fpg, NBBY) - start; |
638 | loc = skpc(0xff, len, &bbp[start]); |
639 | if (loc == 0) { |
640 | len = start + 1; |
641 | start = 0; |
642 | loc = skpc(0xff, len, &bbp[start]); |
643 | if (loc == 0) { |
644 | printf("start = %d, len = %d, fs = %s\n" , |
645 | start, len, fs->e2fs_fsmnt); |
646 | panic("ext2fs_alloccg: map corrupted" ); |
647 | /* NOTREACHED */ |
648 | } |
649 | } |
650 | i = start + len - loc; |
651 | map = bbp[i] ^ 0xff; |
652 | if (map == 0) { |
653 | printf("fs = %s\n" , fs->e2fs_fsmnt); |
654 | panic("ext2fs_mapsearch: block not in map" ); |
655 | } |
656 | return i * NBBY + ffs(map) - 1; |
657 | } |
658 | |
659 | /* |
660 | * Fserr prints the name of a file system with an error diagnostic. |
661 | * |
662 | * The form of the error message is: |
663 | * fs: error message |
664 | */ |
665 | static void |
666 | ext2fs_fserr(struct m_ext2fs *fs, u_int uid, const char *cp) |
667 | { |
668 | |
669 | log(LOG_ERR, "uid %d on %s: %s\n" , uid, fs->e2fs_fsmnt, cp); |
670 | } |
671 | |
672 | static __inline void |
673 | ext2fs_cg_update(struct m_ext2fs *fs, int cg, struct ext2_gd *gd, int nbfree, int nifree, int ndirs, daddr_t ioff) |
674 | { |
675 | /* XXX disk32 */ |
676 | if (nifree) { |
677 | gd->ext2bgd_nifree = h2fs16(fs2h16(gd->ext2bgd_nifree) + nifree); |
678 | /* |
679 | * If we allocated inode on bigger offset than what was |
680 | * ever used before, bump the itable_unused count. This |
681 | * member only ever grows, and is used only for initialization |
682 | * !INODE_ZEROED groups with used inodes. Of course, by the |
683 | * time we get here the itables are already zeroed, but |
684 | * e2fstools fsck.ext4 still checks this. |
685 | */ |
686 | if (E2FS_HAS_GD_CSUM(fs) && nifree < 0 && (ioff+1) >= (fs->e2fs.e2fs_ipg - fs2h16(gd->ext2bgd_itable_unused_lo))) { |
687 | gd->ext2bgd_itable_unused_lo = h2fs16(fs->e2fs.e2fs_ipg - (ioff + 1)); |
688 | } |
689 | |
690 | KASSERT(!E2FS_HAS_GD_CSUM(fs) || gd->ext2bgd_itable_unused_lo <= gd->ext2bgd_nifree); |
691 | } |
692 | |
693 | |
694 | if (nbfree) |
695 | gd->ext2bgd_nbfree = h2fs16(fs2h16(gd->ext2bgd_nbfree) + nbfree); |
696 | |
697 | if (ndirs) |
698 | gd->ext2bgd_ndirs = h2fs16(fs2h16(gd->ext2bgd_ndirs) + ndirs); |
699 | |
700 | if (E2FS_HAS_GD_CSUM(fs)) |
701 | gd->ext2bgd_checksum = ext2fs_cg_get_csum(fs, cg, gd); |
702 | } |
703 | |
704 | /* |
705 | * Compute group description csum. Structure data must be LE (not host). |
706 | * Returned as LE (disk encoding). |
707 | */ |
708 | static uint16_t |
709 | ext2fs_cg_get_csum(struct m_ext2fs *fs, int cg, struct ext2_gd *gd) |
710 | { |
711 | uint16_t crc; |
712 | uint32_t cg_bswapped = h2fs32((uint32_t)cg); |
713 | size_t off; |
714 | |
715 | if (!EXT2F_HAS_ROCOMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) |
716 | return 0; |
717 | |
718 | off = offsetof(struct ext2_gd, ext2bgd_checksum); |
719 | |
720 | crc = crc16(~0, (uint8_t *)fs->e2fs.e2fs_uuid, sizeof(fs->e2fs.e2fs_uuid)); |
721 | crc = crc16(crc, (uint8_t *)&cg_bswapped, sizeof(cg_bswapped)); |
722 | crc = crc16(crc, (uint8_t *)gd, off); |
723 | /* XXX ondisk32 */ |
724 | |
725 | return h2fs16(crc); |
726 | } |
727 | |
728 | static void |
729 | ext2fs_init_bb(struct m_ext2fs *fs, int cg, struct ext2_gd *gd, char *bbp) |
730 | { |
731 | int i; |
732 | |
733 | memset(bbp, 0, fs->e2fs_bsize); |
734 | |
735 | /* |
736 | * No block was ever allocated on this cg before, so the only used |
737 | * blocks are metadata blocks on start of the group. We could optimize |
738 | * this to set by bytes, but since this is done once per the group |
739 | * in lifetime of filesystem, it really is not worth it. |
740 | */ |
741 | for(i=0; i < fs->e2fs.e2fs_bpg - fs2h16(gd->ext2bgd_nbfree); i++) |
742 | setbit(bbp, i); |
743 | } |
744 | |
745 | /* |
746 | * Verify csum and initialize itable if not done already |
747 | */ |
748 | int |
749 | ext2fs_cg_verify_and_initialize(struct vnode *devvp, struct m_ext2fs *fs, int ronly) |
750 | { |
751 | /* XXX disk32 */ |
752 | struct ext2_gd *gd; |
753 | ino_t ioff; |
754 | size_t boff; |
755 | struct buf *bp; |
756 | int cg, i, error; |
757 | |
758 | if (!E2FS_HAS_GD_CSUM(fs)) |
759 | return 0; |
760 | |
761 | for(cg=0; cg < fs->e2fs_ncg; cg++) { |
762 | gd = &fs->e2fs_gd[cg]; |
763 | |
764 | /* Verify checksum */ |
765 | if (gd->ext2bgd_checksum != ext2fs_cg_get_csum(fs, cg, gd)) { |
766 | printf("ext2fs_cg_verify_and_initialize: group %d invalid csum\n" , cg); |
767 | return EINVAL; |
768 | } |
769 | |
770 | /* if mounting read-write, zero itable if not already done */ |
771 | if (ronly || (gd->ext2bgd_flags & h2fs16(E2FS_BG_INODE_ZEROED)) != 0) |
772 | continue; |
773 | |
774 | /* |
775 | * We are skipping already used inodes, zero rest of itable |
776 | * blocks. First block to zero could be only partial wipe, all |
777 | * others are wiped completely. This might take a while, |
778 | * there could be many inode table blocks. We use |
779 | * delayed writes, so this shouldn't block for very |
780 | * long. |
781 | */ |
782 | ioff = fs->e2fs.e2fs_ipg - fs2h16(gd->ext2bgd_itable_unused_lo); |
783 | boff = (ioff % fs->e2fs_ipb) * EXT2_DINODE_SIZE(fs); |
784 | |
785 | for(i = ioff / fs->e2fs_ipb; i < fs->e2fs_itpg; i++) { |
786 | if (boff) { |
787 | /* partial wipe, must read old data */ |
788 | error = bread(devvp, |
789 | EXT2_FSBTODB(fs, fs2h32(gd->ext2bgd_i_tables) + i), |
790 | (int)fs->e2fs_bsize, B_MODIFY, &bp); |
791 | if (error) { |
792 | printf("ext2fs_cg_verify_and_initialize: can't read itable block" ); |
793 | return error; |
794 | } |
795 | memset((char *)bp->b_data + boff, 0, fs->e2fs_bsize - boff); |
796 | boff = 0; |
797 | } else { |
798 | /* |
799 | * Complete wipe, don't need to read data. This |
800 | * assumes nothing else is changing the data. |
801 | */ |
802 | bp = getblk(devvp, |
803 | EXT2_FSBTODB(fs, fs2h32(gd->ext2bgd_i_tables) + i), |
804 | (int)fs->e2fs_bsize, 0, 0); |
805 | clrbuf(bp); |
806 | } |
807 | |
808 | bdwrite(bp); |
809 | } |
810 | |
811 | gd->ext2bgd_flags |= h2fs16(E2FS_BG_INODE_ZEROED); |
812 | gd->ext2bgd_checksum = ext2fs_cg_get_csum(fs, cg, gd); |
813 | fs->e2fs_fmod = 1; |
814 | } |
815 | |
816 | return 0; |
817 | } |
818 | |