1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/ext4/ialloc.c
4 *
5 * Copyright (C) 1992, 1993, 1994, 1995
6 * Remy Card (card@masi.ibp.fr)
7 * Laboratoire MASI - Institut Blaise Pascal
8 * Universite Pierre et Marie Curie (Paris VI)
9 *
10 * BSD ufs-inspired inode and directory allocation by
11 * Stephen Tweedie (sct@redhat.com), 1993
12 * Big-endian to little-endian byte-swapping/bitmaps by
13 * David S. Miller (davem@caip.rutgers.edu), 1995
14 */
15
16#include <linux/time.h>
17#include <linux/fs.h>
18#include <linux/stat.h>
19#include <linux/string.h>
20#include <linux/quotaops.h>
21#include <linux/buffer_head.h>
22#include <linux/random.h>
23#include <linux/bitops.h>
24#include <linux/blkdev.h>
25#include <linux/cred.h>
26
27#include <asm/byteorder.h>
28
29#include "ext4.h"
30#include "ext4_jbd2.h"
31#include "xattr.h"
32#include "acl.h"
33
34#include <trace/events/ext4.h>
35
36/*
37 * ialloc.c contains the inodes allocation and deallocation routines
38 */
39
40/*
41 * The free inodes are managed by bitmaps. A file system contains several
42 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
43 * block for inodes, N blocks for the inode table and data blocks.
44 *
45 * The file system contains group descriptors which are located after the
46 * super block. Each descriptor contains the number of the bitmap block and
47 * the free blocks count in the block.
48 */
49
50/*
51 * To avoid calling the atomic setbit hundreds or thousands of times, we only
52 * need to use it within a single byte (to ensure we get endianness right).
53 * We can use memset for the rest of the bitmap as there are no other users.
54 */
55void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
56{
57 int i;
58
59 if (start_bit >= end_bit)
60 return;
61
62 ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
63 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
64 ext4_set_bit(nr: i, addr: bitmap);
65 if (i < end_bit)
66 memset(s: bitmap + (i >> 3), c: 0xff, n: (end_bit - i) >> 3);
67}
68
69void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate)
70{
71 if (uptodate) {
72 set_buffer_uptodate(bh);
73 set_bitmap_uptodate(bh);
74 }
75 unlock_buffer(bh);
76 put_bh(bh);
77}
78
79static int ext4_validate_inode_bitmap(struct super_block *sb,
80 struct ext4_group_desc *desc,
81 ext4_group_t block_group,
82 struct buffer_head *bh)
83{
84 ext4_fsblk_t blk;
85 struct ext4_group_info *grp;
86
87 if (EXT4_SB(sb)->s_mount_state & EXT4_FC_REPLAY)
88 return 0;
89
90 if (buffer_verified(bh))
91 return 0;
92
93 grp = ext4_get_group_info(sb, group: block_group);
94 if (!grp || EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
95 return -EFSCORRUPTED;
96
97 ext4_lock_group(sb, group: block_group);
98 if (buffer_verified(bh))
99 goto verified;
100 blk = ext4_inode_bitmap(sb, bg: desc);
101 if (!ext4_inode_bitmap_csum_verify(sb, gdp: desc, bh) ||
102 ext4_simulate_fail(sb, EXT4_SIM_IBITMAP_CRC)) {
103 ext4_unlock_group(sb, group: block_group);
104 ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
105 "inode_bitmap = %llu", block_group, blk);
106 ext4_mark_group_bitmap_corrupted(sb, block_group,
107 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
108 return -EFSBADCRC;
109 }
110 set_buffer_verified(bh);
111verified:
112 ext4_unlock_group(sb, group: block_group);
113 return 0;
114}
115
116/*
117 * Read the inode allocation bitmap for a given block_group, reading
118 * into the specified slot in the superblock's bitmap cache.
119 *
120 * Return buffer_head of bitmap on success, or an ERR_PTR on error.
121 */
122static struct buffer_head *
123ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
124{
125 struct ext4_group_desc *desc;
126 struct ext4_sb_info *sbi = EXT4_SB(sb);
127 struct buffer_head *bh = NULL;
128 ext4_fsblk_t bitmap_blk;
129 int err;
130
131 desc = ext4_get_group_desc(sb, block_group, NULL);
132 if (!desc)
133 return ERR_PTR(error: -EFSCORRUPTED);
134
135 bitmap_blk = ext4_inode_bitmap(sb, bg: desc);
136 if ((bitmap_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) ||
137 (bitmap_blk >= ext4_blocks_count(es: sbi->s_es))) {
138 ext4_error(sb, "Invalid inode bitmap blk %llu in "
139 "block_group %u", bitmap_blk, block_group);
140 ext4_mark_group_bitmap_corrupted(sb, block_group,
141 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
142 return ERR_PTR(error: -EFSCORRUPTED);
143 }
144 bh = sb_getblk(sb, block: bitmap_blk);
145 if (unlikely(!bh)) {
146 ext4_warning(sb, "Cannot read inode bitmap - "
147 "block_group = %u, inode_bitmap = %llu",
148 block_group, bitmap_blk);
149 return ERR_PTR(error: -ENOMEM);
150 }
151 if (bitmap_uptodate(bh))
152 goto verify;
153
154 lock_buffer(bh);
155 if (bitmap_uptodate(bh)) {
156 unlock_buffer(bh);
157 goto verify;
158 }
159
160 ext4_lock_group(sb, group: block_group);
161 if (ext4_has_group_desc_csum(sb) &&
162 (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT))) {
163 if (block_group == 0) {
164 ext4_unlock_group(sb, group: block_group);
165 unlock_buffer(bh);
166 ext4_error(sb, "Inode bitmap for bg 0 marked "
167 "uninitialized");
168 err = -EFSCORRUPTED;
169 goto out;
170 }
171 memset(s: bh->b_data, c: 0, n: (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
172 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb),
173 end_bit: sb->s_blocksize * 8, bitmap: bh->b_data);
174 set_bitmap_uptodate(bh);
175 set_buffer_uptodate(bh);
176 set_buffer_verified(bh);
177 ext4_unlock_group(sb, group: block_group);
178 unlock_buffer(bh);
179 return bh;
180 }
181 ext4_unlock_group(sb, group: block_group);
182
183 if (buffer_uptodate(bh)) {
184 /*
185 * if not uninit if bh is uptodate,
186 * bitmap is also uptodate
187 */
188 set_bitmap_uptodate(bh);
189 unlock_buffer(bh);
190 goto verify;
191 }
192 /*
193 * submit the buffer_head for reading
194 */
195 trace_ext4_load_inode_bitmap(sb, group: block_group);
196 ext4_read_bh(bh, REQ_META | REQ_PRIO,
197 end_io: ext4_end_bitmap_read,
198 simu_fail: ext4_simulate_fail(sb, EXT4_SIM_IBITMAP_EIO));
199 if (!buffer_uptodate(bh)) {
200 put_bh(bh);
201 ext4_error_err(sb, EIO, "Cannot read inode bitmap - "
202 "block_group = %u, inode_bitmap = %llu",
203 block_group, bitmap_blk);
204 ext4_mark_group_bitmap_corrupted(sb, block_group,
205 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
206 return ERR_PTR(error: -EIO);
207 }
208
209verify:
210 err = ext4_validate_inode_bitmap(sb, desc, block_group, bh);
211 if (err)
212 goto out;
213 return bh;
214out:
215 put_bh(bh);
216 return ERR_PTR(error: err);
217}
218
219/*
220 * NOTE! When we get the inode, we're the only people
221 * that have access to it, and as such there are no
222 * race conditions we have to worry about. The inode
223 * is not on the hash-lists, and it cannot be reached
224 * through the filesystem because the directory entry
225 * has been deleted earlier.
226 *
227 * HOWEVER: we must make sure that we get no aliases,
228 * which means that we have to call "clear_inode()"
229 * _before_ we mark the inode not in use in the inode
230 * bitmaps. Otherwise a newly created file might use
231 * the same inode number (not actually the same pointer
232 * though), and then we'd have two inodes sharing the
233 * same inode number and space on the harddisk.
234 */
235void ext4_free_inode(handle_t *handle, struct inode *inode)
236{
237 struct super_block *sb = inode->i_sb;
238 int is_directory;
239 unsigned long ino;
240 struct buffer_head *bitmap_bh = NULL;
241 struct buffer_head *bh2;
242 ext4_group_t block_group;
243 unsigned long bit;
244 struct ext4_group_desc *gdp;
245 struct ext4_super_block *es;
246 struct ext4_sb_info *sbi;
247 int fatal = 0, err, count, cleared;
248 struct ext4_group_info *grp;
249
250 if (!sb) {
251 printk(KERN_ERR "EXT4-fs: %s:%d: inode on "
252 "nonexistent device\n", __func__, __LINE__);
253 return;
254 }
255 if (icount_read(inode) > 1) {
256 ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: count=%d",
257 __func__, __LINE__, inode->i_ino,
258 icount_read(inode));
259 return;
260 }
261 if (inode->i_nlink) {
262 ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: nlink=%d\n",
263 __func__, __LINE__, inode->i_ino, inode->i_nlink);
264 return;
265 }
266 sbi = EXT4_SB(sb);
267
268 ino = inode->i_ino;
269 ext4_debug("freeing inode %lu\n", ino);
270 trace_ext4_free_inode(inode);
271
272 dquot_initialize(inode);
273 dquot_free_inode(inode);
274
275 is_directory = S_ISDIR(inode->i_mode);
276
277 /* Do this BEFORE marking the inode not in use or returning an error */
278 ext4_clear_inode(inode);
279
280 es = sbi->s_es;
281 if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
282 ext4_error(sb, "reserved or nonexistent inode %lu", ino);
283 goto error_return;
284 }
285 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
286 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
287 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
288 /* Don't bother if the inode bitmap is corrupt. */
289 if (IS_ERR(ptr: bitmap_bh)) {
290 fatal = PTR_ERR(ptr: bitmap_bh);
291 bitmap_bh = NULL;
292 goto error_return;
293 }
294 if (!(sbi->s_mount_state & EXT4_FC_REPLAY)) {
295 grp = ext4_get_group_info(sb, group: block_group);
296 if (!grp || unlikely(EXT4_MB_GRP_IBITMAP_CORRUPT(grp))) {
297 fatal = -EFSCORRUPTED;
298 goto error_return;
299 }
300 }
301
302 BUFFER_TRACE(bitmap_bh, "get_write_access");
303 fatal = ext4_journal_get_write_access(handle, sb, bitmap_bh,
304 EXT4_JTR_NONE);
305 if (fatal)
306 goto error_return;
307
308 fatal = -ESRCH;
309 gdp = ext4_get_group_desc(sb, block_group, bh: &bh2);
310 if (gdp) {
311 BUFFER_TRACE(bh2, "get_write_access");
312 fatal = ext4_journal_get_write_access(handle, sb, bh2,
313 EXT4_JTR_NONE);
314 }
315 ext4_lock_group(sb, group: block_group);
316 cleared = ext4_test_and_clear_bit(nr: bit, addr: bitmap_bh->b_data);
317 if (fatal || !cleared) {
318 ext4_unlock_group(sb, group: block_group);
319 goto out;
320 }
321
322 count = ext4_free_inodes_count(sb, bg: gdp) + 1;
323 ext4_free_inodes_set(sb, bg: gdp, count);
324 if (is_directory) {
325 count = ext4_used_dirs_count(sb, bg: gdp) - 1;
326 ext4_used_dirs_set(sb, bg: gdp, count);
327 if (percpu_counter_initialized(fbc: &sbi->s_dirs_counter))
328 percpu_counter_dec(fbc: &sbi->s_dirs_counter);
329 }
330 ext4_inode_bitmap_csum_set(sb, gdp, bh: bitmap_bh);
331 ext4_group_desc_csum_set(sb, group: block_group, gdp);
332 ext4_unlock_group(sb, group: block_group);
333
334 if (percpu_counter_initialized(fbc: &sbi->s_freeinodes_counter))
335 percpu_counter_inc(fbc: &sbi->s_freeinodes_counter);
336 if (sbi->s_log_groups_per_flex) {
337 struct flex_groups *fg;
338
339 fg = sbi_array_rcu_deref(sbi, s_flex_groups,
340 ext4_flex_group(sbi, block_group));
341 atomic_inc(v: &fg->free_inodes);
342 if (is_directory)
343 atomic_dec(v: &fg->used_dirs);
344 }
345 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
346 fatal = ext4_handle_dirty_metadata(handle, NULL, bh2);
347out:
348 if (cleared) {
349 BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
350 err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
351 if (!fatal)
352 fatal = err;
353 } else {
354 ext4_error(sb, "bit already cleared for inode %lu", ino);
355 ext4_mark_group_bitmap_corrupted(sb, block_group,
356 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
357 }
358
359error_return:
360 brelse(bh: bitmap_bh);
361 ext4_std_error(sb, fatal);
362}
363
364struct orlov_stats {
365 __u64 free_clusters;
366 __u32 free_inodes;
367 __u32 used_dirs;
368};
369
370/*
371 * Helper function for Orlov's allocator; returns critical information
372 * for a particular block group or flex_bg. If flex_size is 1, then g
373 * is a block group number; otherwise it is flex_bg number.
374 */
375static void get_orlov_stats(struct super_block *sb, ext4_group_t g,
376 int flex_size, struct orlov_stats *stats)
377{
378 struct ext4_group_desc *desc;
379
380 if (flex_size > 1) {
381 struct flex_groups *fg = sbi_array_rcu_deref(EXT4_SB(sb),
382 s_flex_groups, g);
383 stats->free_inodes = atomic_read(v: &fg->free_inodes);
384 stats->free_clusters = atomic64_read(v: &fg->free_clusters);
385 stats->used_dirs = atomic_read(v: &fg->used_dirs);
386 return;
387 }
388
389 desc = ext4_get_group_desc(sb, block_group: g, NULL);
390 if (desc) {
391 stats->free_inodes = ext4_free_inodes_count(sb, bg: desc);
392 stats->free_clusters = ext4_free_group_clusters(sb, bg: desc);
393 stats->used_dirs = ext4_used_dirs_count(sb, bg: desc);
394 } else {
395 stats->free_inodes = 0;
396 stats->free_clusters = 0;
397 stats->used_dirs = 0;
398 }
399}
400
401/*
402 * Orlov's allocator for directories.
403 *
404 * We always try to spread first-level directories.
405 *
406 * If there are blockgroups with both free inodes and free clusters counts
407 * not worse than average we return one with smallest directory count.
408 * Otherwise we simply return a random group.
409 *
410 * For the rest rules look so:
411 *
412 * It's OK to put directory into a group unless
413 * it has too many directories already (max_dirs) or
414 * it has too few free inodes left (min_inodes) or
415 * it has too few free clusters left (min_clusters) or
416 * Parent's group is preferred, if it doesn't satisfy these
417 * conditions we search cyclically through the rest. If none
418 * of the groups look good we just look for a group with more
419 * free inodes than average (starting at parent's group).
420 */
421
422static int find_group_orlov(struct super_block *sb, struct inode *parent,
423 ext4_group_t *group, umode_t mode,
424 const struct qstr *qstr)
425{
426 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
427 struct ext4_sb_info *sbi = EXT4_SB(sb);
428 ext4_group_t real_ngroups = ext4_get_groups_count(sb);
429 int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
430 unsigned int freei, avefreei, grp_free;
431 ext4_fsblk_t freec, avefreec;
432 unsigned int ndirs;
433 int max_dirs, min_inodes;
434 ext4_grpblk_t min_clusters;
435 ext4_group_t i, grp, g, ngroups;
436 struct ext4_group_desc *desc;
437 struct orlov_stats stats;
438 int flex_size = ext4_flex_bg_size(sbi);
439 struct dx_hash_info hinfo;
440
441 ngroups = real_ngroups;
442 if (flex_size > 1) {
443 ngroups = (real_ngroups + flex_size - 1) >>
444 sbi->s_log_groups_per_flex;
445 parent_group >>= sbi->s_log_groups_per_flex;
446 }
447
448 freei = percpu_counter_read_positive(fbc: &sbi->s_freeinodes_counter);
449 avefreei = freei / ngroups;
450 freec = percpu_counter_read_positive(fbc: &sbi->s_freeclusters_counter);
451 avefreec = freec;
452 do_div(avefreec, ngroups);
453 ndirs = percpu_counter_read_positive(fbc: &sbi->s_dirs_counter);
454
455 if (S_ISDIR(mode) &&
456 ((parent == d_inode(dentry: sb->s_root)) ||
457 (ext4_test_inode_flag(inode: parent, bit: EXT4_INODE_TOPDIR)))) {
458 int best_ndir = inodes_per_group;
459 int ret = -1;
460
461 if (qstr) {
462 hinfo.hash_version = DX_HASH_HALF_MD4;
463 hinfo.seed = sbi->s_hash_seed;
464 ext4fs_dirhash(dir: parent, name: qstr->name, len: qstr->len, hinfo: &hinfo);
465 parent_group = hinfo.hash % ngroups;
466 } else
467 parent_group = get_random_u32_below(ceil: ngroups);
468 for (i = 0; i < ngroups; i++) {
469 g = (parent_group + i) % ngroups;
470 get_orlov_stats(sb, g, flex_size, stats: &stats);
471 if (!stats.free_inodes)
472 continue;
473 if (stats.used_dirs >= best_ndir)
474 continue;
475 if (stats.free_inodes < avefreei)
476 continue;
477 if (stats.free_clusters < avefreec)
478 continue;
479 grp = g;
480 ret = 0;
481 best_ndir = stats.used_dirs;
482 }
483 if (ret)
484 goto fallback;
485 found_flex_bg:
486 if (flex_size == 1) {
487 *group = grp;
488 return 0;
489 }
490
491 /*
492 * We pack inodes at the beginning of the flexgroup's
493 * inode tables. Block allocation decisions will do
494 * something similar, although regular files will
495 * start at 2nd block group of the flexgroup. See
496 * ext4_ext_find_goal() and ext4_find_near().
497 */
498 grp *= flex_size;
499 for (i = 0; i < flex_size; i++) {
500 if (grp+i >= real_ngroups)
501 break;
502 desc = ext4_get_group_desc(sb, block_group: grp+i, NULL);
503 if (desc && ext4_free_inodes_count(sb, bg: desc)) {
504 *group = grp+i;
505 return 0;
506 }
507 }
508 goto fallback;
509 }
510
511 max_dirs = ndirs / ngroups + inodes_per_group*flex_size / 16;
512 min_inodes = avefreei - inodes_per_group*flex_size / 4;
513 if (min_inodes < 1)
514 min_inodes = 1;
515 min_clusters = avefreec - EXT4_CLUSTERS_PER_GROUP(sb)*flex_size / 4;
516 if (min_clusters < 0)
517 min_clusters = 0;
518
519 /*
520 * Start looking in the flex group where we last allocated an
521 * inode for this parent directory
522 */
523 if (EXT4_I(parent)->i_last_alloc_group != ~0) {
524 parent_group = EXT4_I(parent)->i_last_alloc_group;
525 if (flex_size > 1)
526 parent_group >>= sbi->s_log_groups_per_flex;
527 }
528
529 for (i = 0; i < ngroups; i++) {
530 grp = (parent_group + i) % ngroups;
531 get_orlov_stats(sb, g: grp, flex_size, stats: &stats);
532 if (stats.used_dirs >= max_dirs)
533 continue;
534 if (stats.free_inodes < min_inodes)
535 continue;
536 if (stats.free_clusters < min_clusters)
537 continue;
538 goto found_flex_bg;
539 }
540
541fallback:
542 ngroups = real_ngroups;
543 avefreei = freei / ngroups;
544fallback_retry:
545 parent_group = EXT4_I(parent)->i_block_group;
546 for (i = 0; i < ngroups; i++) {
547 grp = (parent_group + i) % ngroups;
548 desc = ext4_get_group_desc(sb, block_group: grp, NULL);
549 if (desc) {
550 grp_free = ext4_free_inodes_count(sb, bg: desc);
551 if (grp_free && grp_free >= avefreei) {
552 *group = grp;
553 return 0;
554 }
555 }
556 }
557
558 if (avefreei) {
559 /*
560 * The free-inodes counter is approximate, and for really small
561 * filesystems the above test can fail to find any blockgroups
562 */
563 avefreei = 0;
564 goto fallback_retry;
565 }
566
567 return -1;
568}
569
570static int find_group_other(struct super_block *sb, struct inode *parent,
571 ext4_group_t *group, umode_t mode)
572{
573 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
574 ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
575 struct ext4_group_desc *desc;
576 int flex_size = ext4_flex_bg_size(sbi: EXT4_SB(sb));
577
578 /*
579 * Try to place the inode is the same flex group as its
580 * parent. If we can't find space, use the Orlov algorithm to
581 * find another flex group, and store that information in the
582 * parent directory's inode information so that use that flex
583 * group for future allocations.
584 */
585 if (flex_size > 1) {
586 int retry = 0;
587
588 try_again:
589 parent_group &= ~(flex_size-1);
590 last = parent_group + flex_size;
591 if (last > ngroups)
592 last = ngroups;
593 for (i = parent_group; i < last; i++) {
594 desc = ext4_get_group_desc(sb, block_group: i, NULL);
595 if (desc && ext4_free_inodes_count(sb, bg: desc)) {
596 *group = i;
597 return 0;
598 }
599 }
600 if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
601 retry = 1;
602 parent_group = EXT4_I(parent)->i_last_alloc_group;
603 goto try_again;
604 }
605 /*
606 * If this didn't work, use the Orlov search algorithm
607 * to find a new flex group; we pass in the mode to
608 * avoid the topdir algorithms.
609 */
610 *group = parent_group + flex_size;
611 if (*group > ngroups)
612 *group = 0;
613 return find_group_orlov(sb, parent, group, mode, NULL);
614 }
615
616 /*
617 * Try to place the inode in its parent directory
618 */
619 *group = parent_group;
620 desc = ext4_get_group_desc(sb, block_group: *group, NULL);
621 if (desc && ext4_free_inodes_count(sb, bg: desc) &&
622 ext4_free_group_clusters(sb, bg: desc))
623 return 0;
624
625 /*
626 * We're going to place this inode in a different blockgroup from its
627 * parent. We want to cause files in a common directory to all land in
628 * the same blockgroup. But we want files which are in a different
629 * directory which shares a blockgroup with our parent to land in a
630 * different blockgroup.
631 *
632 * So add our directory's i_ino into the starting point for the hash.
633 */
634 *group = (*group + parent->i_ino) % ngroups;
635
636 /*
637 * Use a quadratic hash to find a group with a free inode and some free
638 * blocks.
639 */
640 for (i = 1; i < ngroups; i <<= 1) {
641 *group += i;
642 if (*group >= ngroups)
643 *group -= ngroups;
644 desc = ext4_get_group_desc(sb, block_group: *group, NULL);
645 if (desc && ext4_free_inodes_count(sb, bg: desc) &&
646 ext4_free_group_clusters(sb, bg: desc))
647 return 0;
648 }
649
650 /*
651 * That failed: try linear search for a free inode, even if that group
652 * has no free blocks.
653 */
654 *group = parent_group;
655 for (i = 0; i < ngroups; i++) {
656 if (++*group >= ngroups)
657 *group = 0;
658 desc = ext4_get_group_desc(sb, block_group: *group, NULL);
659 if (desc && ext4_free_inodes_count(sb, bg: desc))
660 return 0;
661 }
662
663 return -1;
664}
665
666/*
667 * In no journal mode, if an inode has recently been deleted, we want
668 * to avoid reusing it until we're reasonably sure the inode table
669 * block has been written back to disk. (Yes, these values are
670 * somewhat arbitrary...)
671 */
672#define RECENTCY_MIN 60
673#define RECENTCY_DIRTY 300
674
675static int recently_deleted(struct super_block *sb, ext4_group_t group, int ino)
676{
677 struct ext4_group_desc *gdp;
678 struct ext4_inode *raw_inode;
679 struct buffer_head *bh;
680 int inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
681 int offset, ret = 0;
682 int recentcy = RECENTCY_MIN;
683 u32 dtime, now;
684
685 gdp = ext4_get_group_desc(sb, block_group: group, NULL);
686 if (unlikely(!gdp))
687 return 0;
688
689 bh = sb_find_get_block(sb, block: ext4_inode_table(sb, bg: gdp) +
690 (ino / inodes_per_block));
691 if (!bh || !buffer_uptodate(bh))
692 /*
693 * If the block is not in the buffer cache, then it
694 * must have been written out, or, most unlikely, is
695 * being migrated - false failure should be OK here.
696 */
697 goto out;
698
699 offset = (ino % inodes_per_block) * EXT4_INODE_SIZE(sb);
700 raw_inode = (struct ext4_inode *) (bh->b_data + offset);
701
702 /* i_dtime is only 32 bits on disk, but we only care about relative
703 * times in the range of a few minutes (i.e. long enough to sync a
704 * recently-deleted inode to disk), so using the low 32 bits of the
705 * clock (a 68 year range) is enough, see time_before32() */
706 dtime = le32_to_cpu(raw_inode->i_dtime);
707 now = ktime_get_real_seconds();
708 if (buffer_dirty(bh))
709 recentcy += RECENTCY_DIRTY;
710
711 if (dtime && time_before32(dtime, now) &&
712 time_before32(now, dtime + recentcy))
713 ret = 1;
714out:
715 brelse(bh);
716 return ret;
717}
718
719static int find_inode_bit(struct super_block *sb, ext4_group_t group,
720 struct buffer_head *bitmap, unsigned long *ino)
721{
722 bool check_recently_deleted = EXT4_SB(sb)->s_journal == NULL;
723 unsigned long recently_deleted_ino = EXT4_INODES_PER_GROUP(sb);
724
725next:
726 *ino = ext4_find_next_zero_bit(addr: (unsigned long *)
727 bitmap->b_data,
728 EXT4_INODES_PER_GROUP(sb), offset: *ino);
729 if (*ino >= EXT4_INODES_PER_GROUP(sb))
730 goto not_found;
731
732 if (check_recently_deleted && recently_deleted(sb, group, ino: *ino)) {
733 recently_deleted_ino = *ino;
734 *ino = *ino + 1;
735 if (*ino < EXT4_INODES_PER_GROUP(sb))
736 goto next;
737 goto not_found;
738 }
739 return 1;
740not_found:
741 if (recently_deleted_ino >= EXT4_INODES_PER_GROUP(sb))
742 return 0;
743 /*
744 * Not reusing recently deleted inodes is mostly a preference. We don't
745 * want to report ENOSPC or skew allocation patterns because of that.
746 * So return even recently deleted inode if we could find better in the
747 * given range.
748 */
749 *ino = recently_deleted_ino;
750 return 1;
751}
752
753int ext4_mark_inode_used(struct super_block *sb, int ino)
754{
755 unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
756 struct buffer_head *inode_bitmap_bh = NULL, *group_desc_bh = NULL;
757 struct ext4_group_desc *gdp;
758 ext4_group_t group;
759 int bit;
760 int err;
761
762 if (ino < EXT4_FIRST_INO(sb) || ino > max_ino)
763 return -EFSCORRUPTED;
764
765 group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
766 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
767 inode_bitmap_bh = ext4_read_inode_bitmap(sb, block_group: group);
768 if (IS_ERR(ptr: inode_bitmap_bh))
769 return PTR_ERR(ptr: inode_bitmap_bh);
770
771 if (ext4_test_bit(nr: bit, addr: inode_bitmap_bh->b_data)) {
772 err = 0;
773 goto out;
774 }
775
776 gdp = ext4_get_group_desc(sb, block_group: group, bh: &group_desc_bh);
777 if (!gdp) {
778 err = -EINVAL;
779 goto out;
780 }
781
782 ext4_set_bit(nr: bit, addr: inode_bitmap_bh->b_data);
783
784 BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
785 err = ext4_handle_dirty_metadata(NULL, NULL, inode_bitmap_bh);
786 if (err) {
787 ext4_std_error(sb, err);
788 goto out;
789 }
790 err = sync_dirty_buffer(bh: inode_bitmap_bh);
791 if (err) {
792 ext4_std_error(sb, err);
793 goto out;
794 }
795
796 /* We may have to initialize the block bitmap if it isn't already */
797 if (ext4_has_group_desc_csum(sb) &&
798 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
799 struct buffer_head *block_bitmap_bh;
800
801 block_bitmap_bh = ext4_read_block_bitmap(sb, block_group: group);
802 if (IS_ERR(ptr: block_bitmap_bh)) {
803 err = PTR_ERR(ptr: block_bitmap_bh);
804 goto out;
805 }
806
807 BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
808 err = ext4_handle_dirty_metadata(NULL, NULL, block_bitmap_bh);
809 sync_dirty_buffer(bh: block_bitmap_bh);
810
811 /* recheck and clear flag under lock if we still need to */
812 ext4_lock_group(sb, group);
813 if (ext4_has_group_desc_csum(sb) &&
814 (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
815 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
816 ext4_free_group_clusters_set(sb, bg: gdp,
817 count: ext4_free_clusters_after_init(sb, block_group: group, gdp));
818 ext4_block_bitmap_csum_set(sb, gdp, bh: block_bitmap_bh);
819 ext4_group_desc_csum_set(sb, group, gdp);
820 }
821 ext4_unlock_group(sb, group);
822 brelse(bh: block_bitmap_bh);
823
824 if (err) {
825 ext4_std_error(sb, err);
826 goto out;
827 }
828 }
829
830 /* Update the relevant bg descriptor fields */
831 if (ext4_has_group_desc_csum(sb)) {
832 int free;
833
834 ext4_lock_group(sb, group); /* while we modify the bg desc */
835 free = EXT4_INODES_PER_GROUP(sb) -
836 ext4_itable_unused_count(sb, bg: gdp);
837 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
838 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
839 free = 0;
840 }
841
842 /*
843 * Check the relative inode number against the last used
844 * relative inode number in this group. if it is greater
845 * we need to update the bg_itable_unused count
846 */
847 if (bit >= free)
848 ext4_itable_unused_set(sb, bg: gdp,
849 count: (EXT4_INODES_PER_GROUP(sb) - bit - 1));
850 } else {
851 ext4_lock_group(sb, group);
852 }
853
854 ext4_free_inodes_set(sb, bg: gdp, count: ext4_free_inodes_count(sb, bg: gdp) - 1);
855 if (ext4_has_group_desc_csum(sb)) {
856 ext4_inode_bitmap_csum_set(sb, gdp, bh: inode_bitmap_bh);
857 ext4_group_desc_csum_set(sb, group, gdp);
858 }
859
860 ext4_unlock_group(sb, group);
861 err = ext4_handle_dirty_metadata(NULL, NULL, group_desc_bh);
862 sync_dirty_buffer(bh: group_desc_bh);
863out:
864 brelse(bh: inode_bitmap_bh);
865 return err;
866}
867
868static int ext4_xattr_credits_for_new_inode(struct inode *dir, mode_t mode,
869 bool encrypt)
870{
871 struct super_block *sb = dir->i_sb;
872 int nblocks = 0;
873#ifdef CONFIG_EXT4_FS_POSIX_ACL
874 struct posix_acl *p = get_inode_acl(inode: dir, ACL_TYPE_DEFAULT);
875
876 if (IS_ERR(ptr: p))
877 return PTR_ERR(ptr: p);
878 if (p) {
879 int acl_size = p->a_count * sizeof(ext4_acl_entry);
880
881 nblocks += (S_ISDIR(mode) ? 2 : 1) *
882 __ext4_xattr_set_credits(sb, NULL /* inode */,
883 NULL /* block_bh */, value_len: acl_size,
884 is_create: true /* is_create */);
885 posix_acl_release(acl: p);
886 }
887#endif
888
889#ifdef CONFIG_SECURITY
890 {
891 int num_security_xattrs = 1;
892
893#ifdef CONFIG_INTEGRITY
894 num_security_xattrs++;
895#endif
896 /*
897 * We assume that security xattrs are never more than 1k.
898 * In practice they are under 128 bytes.
899 */
900 nblocks += num_security_xattrs *
901 __ext4_xattr_set_credits(sb, NULL /* inode */,
902 NULL /* block_bh */, value_len: 1024,
903 is_create: true /* is_create */);
904 }
905#endif
906 if (encrypt)
907 nblocks += __ext4_xattr_set_credits(sb,
908 NULL /* inode */,
909 NULL /* block_bh */,
910 FSCRYPT_SET_CONTEXT_MAX_SIZE,
911 is_create: true /* is_create */);
912 return nblocks;
913}
914
915/*
916 * There are two policies for allocating an inode. If the new inode is
917 * a directory, then a forward search is made for a block group with both
918 * free space and a low directory-to-inode ratio; if that fails, then of
919 * the groups with above-average free space, that group with the fewest
920 * directories already is chosen.
921 *
922 * For other inodes, search forward from the parent directory's block
923 * group to find a free inode.
924 */
925struct inode *__ext4_new_inode(struct mnt_idmap *idmap,
926 handle_t *handle, struct inode *dir,
927 umode_t mode, const struct qstr *qstr,
928 __u32 goal, uid_t *owner, __u32 i_flags,
929 int handle_type, unsigned int line_no,
930 int nblocks)
931{
932 struct super_block *sb;
933 struct buffer_head *inode_bitmap_bh = NULL;
934 struct buffer_head *group_desc_bh;
935 ext4_group_t ngroups, group = 0;
936 unsigned long ino = 0;
937 struct inode *inode;
938 struct ext4_group_desc *gdp = NULL;
939 struct ext4_inode_info *ei;
940 struct ext4_sb_info *sbi;
941 int ret2, err;
942 struct inode *ret;
943 ext4_group_t i;
944 ext4_group_t flex_group;
945 struct ext4_group_info *grp = NULL;
946 bool encrypt = false;
947
948 /* Cannot create files in a deleted directory */
949 if (!dir || !dir->i_nlink)
950 return ERR_PTR(error: -EPERM);
951
952 sb = dir->i_sb;
953 sbi = EXT4_SB(sb);
954
955 ret2 = ext4_emergency_state(sb);
956 if (unlikely(ret2))
957 return ERR_PTR(error: ret2);
958
959 ngroups = ext4_get_groups_count(sb);
960 trace_ext4_request_inode(dir, mode);
961 inode = new_inode(sb);
962 if (!inode)
963 return ERR_PTR(error: -ENOMEM);
964 ei = EXT4_I(inode);
965
966 /*
967 * Initialize owners and quota early so that we don't have to account
968 * for quota initialization worst case in standard inode creating
969 * transaction
970 */
971 if (owner) {
972 inode->i_mode = mode;
973 i_uid_write(inode, uid: owner[0]);
974 i_gid_write(inode, gid: owner[1]);
975 } else if (test_opt(sb, GRPID)) {
976 inode->i_mode = mode;
977 inode_fsuid_set(inode, idmap);
978 inode->i_gid = dir->i_gid;
979 } else
980 inode_init_owner(idmap, inode, dir, mode);
981
982 if (ext4_has_feature_project(sb) &&
983 ext4_test_inode_flag(inode: dir, bit: EXT4_INODE_PROJINHERIT))
984 ei->i_projid = EXT4_I(dir)->i_projid;
985 else
986 ei->i_projid = make_kprojid(from: &init_user_ns, EXT4_DEF_PROJID);
987
988 if (!(i_flags & EXT4_EA_INODE_FL)) {
989 err = fscrypt_prepare_new_inode(dir, inode, encrypt_ret: &encrypt);
990 if (err)
991 goto out;
992 }
993
994 err = dquot_initialize(inode);
995 if (err)
996 goto out;
997
998 if (!handle && sbi->s_journal && !(i_flags & EXT4_EA_INODE_FL)) {
999 ret2 = ext4_xattr_credits_for_new_inode(dir, mode, encrypt);
1000 if (ret2 < 0) {
1001 err = ret2;
1002 goto out;
1003 }
1004 nblocks += ret2;
1005 }
1006
1007 if (!goal)
1008 goal = sbi->s_inode_goal;
1009
1010 if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
1011 group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
1012 ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
1013 ret2 = 0;
1014 goto got_group;
1015 }
1016
1017 if (S_ISDIR(mode))
1018 ret2 = find_group_orlov(sb, parent: dir, group: &group, mode, qstr);
1019 else
1020 ret2 = find_group_other(sb, parent: dir, group: &group, mode);
1021
1022got_group:
1023 EXT4_I(dir)->i_last_alloc_group = group;
1024 err = -ENOSPC;
1025 if (ret2 == -1)
1026 goto out;
1027
1028 /*
1029 * Normally we will only go through one pass of this loop,
1030 * unless we get unlucky and it turns out the group we selected
1031 * had its last inode grabbed by someone else.
1032 */
1033 for (i = 0; i < ngroups; i++, ino = 0) {
1034 err = -EIO;
1035
1036 gdp = ext4_get_group_desc(sb, block_group: group, bh: &group_desc_bh);
1037 if (!gdp)
1038 goto out;
1039
1040 /*
1041 * Check free inodes count before loading bitmap.
1042 */
1043 if (ext4_free_inodes_count(sb, bg: gdp) == 0)
1044 goto next_group;
1045
1046 if (!(sbi->s_mount_state & EXT4_FC_REPLAY)) {
1047 grp = ext4_get_group_info(sb, group);
1048 /*
1049 * Skip groups with already-known suspicious inode
1050 * tables
1051 */
1052 if (!grp || EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
1053 goto next_group;
1054 }
1055
1056 brelse(bh: inode_bitmap_bh);
1057 inode_bitmap_bh = ext4_read_inode_bitmap(sb, block_group: group);
1058 /* Skip groups with suspicious inode tables */
1059 if (IS_ERR(ptr: inode_bitmap_bh)) {
1060 inode_bitmap_bh = NULL;
1061 goto next_group;
1062 }
1063 if (!(sbi->s_mount_state & EXT4_FC_REPLAY) &&
1064 EXT4_MB_GRP_IBITMAP_CORRUPT(grp))
1065 goto next_group;
1066
1067 ret2 = find_inode_bit(sb, group, bitmap: inode_bitmap_bh, ino: &ino);
1068 if (!ret2)
1069 goto next_group;
1070
1071 if (group == 0 && (ino + 1) < EXT4_FIRST_INO(sb)) {
1072 ext4_error(sb, "reserved inode found cleared - "
1073 "inode=%lu", ino + 1);
1074 ext4_mark_group_bitmap_corrupted(sb, block_group: group,
1075 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
1076 goto next_group;
1077 }
1078
1079 if ((!(sbi->s_mount_state & EXT4_FC_REPLAY)) && !handle) {
1080 BUG_ON(nblocks <= 0);
1081 handle = __ext4_journal_start_sb(NULL, sb: dir->i_sb,
1082 line: line_no, type: handle_type, blocks: nblocks, rsv_blocks: 0,
1083 revoke_creds: ext4_trans_default_revoke_credits(sb));
1084 if (IS_ERR(ptr: handle)) {
1085 err = PTR_ERR(ptr: handle);
1086 ext4_std_error(sb, err);
1087 goto out;
1088 }
1089 }
1090 BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
1091 err = ext4_journal_get_write_access(handle, sb, inode_bitmap_bh,
1092 EXT4_JTR_NONE);
1093 if (err) {
1094 ext4_std_error(sb, err);
1095 goto out;
1096 }
1097 ext4_lock_group(sb, group);
1098 ret2 = ext4_test_and_set_bit(nr: ino, addr: inode_bitmap_bh->b_data);
1099 if (ret2) {
1100 /* Someone already took the bit. Repeat the search
1101 * with lock held.
1102 */
1103 ret2 = find_inode_bit(sb, group, bitmap: inode_bitmap_bh, ino: &ino);
1104 if (ret2) {
1105 ext4_set_bit(nr: ino, addr: inode_bitmap_bh->b_data);
1106 ret2 = 0;
1107 } else {
1108 ret2 = 1; /* we didn't grab the inode */
1109 }
1110 }
1111 ext4_unlock_group(sb, group);
1112 ino++; /* the inode bitmap is zero-based */
1113 if (!ret2)
1114 goto got; /* we grabbed the inode! */
1115
1116next_group:
1117 if (++group == ngroups)
1118 group = 0;
1119 }
1120 err = -ENOSPC;
1121 goto out;
1122
1123got:
1124 BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
1125 err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh);
1126 if (err) {
1127 ext4_std_error(sb, err);
1128 goto out;
1129 }
1130
1131 BUFFER_TRACE(group_desc_bh, "get_write_access");
1132 err = ext4_journal_get_write_access(handle, sb, group_desc_bh,
1133 EXT4_JTR_NONE);
1134 if (err) {
1135 ext4_std_error(sb, err);
1136 goto out;
1137 }
1138
1139 /* We may have to initialize the block bitmap if it isn't already */
1140 if (ext4_has_group_desc_csum(sb) &&
1141 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
1142 struct buffer_head *block_bitmap_bh;
1143
1144 block_bitmap_bh = ext4_read_block_bitmap(sb, block_group: group);
1145 if (IS_ERR(ptr: block_bitmap_bh)) {
1146 err = PTR_ERR(ptr: block_bitmap_bh);
1147 goto out;
1148 }
1149 BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
1150 err = ext4_journal_get_write_access(handle, sb, block_bitmap_bh,
1151 EXT4_JTR_NONE);
1152 if (err) {
1153 brelse(bh: block_bitmap_bh);
1154 ext4_std_error(sb, err);
1155 goto out;
1156 }
1157
1158 BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
1159 err = ext4_handle_dirty_metadata(handle, NULL, block_bitmap_bh);
1160
1161 /* recheck and clear flag under lock if we still need to */
1162 ext4_lock_group(sb, group);
1163 if (ext4_has_group_desc_csum(sb) &&
1164 (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT))) {
1165 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
1166 ext4_free_group_clusters_set(sb, bg: gdp,
1167 count: ext4_free_clusters_after_init(sb, block_group: group, gdp));
1168 ext4_block_bitmap_csum_set(sb, gdp, bh: block_bitmap_bh);
1169 ext4_group_desc_csum_set(sb, group, gdp);
1170 }
1171 ext4_unlock_group(sb, group);
1172 brelse(bh: block_bitmap_bh);
1173
1174 if (err) {
1175 ext4_std_error(sb, err);
1176 goto out;
1177 }
1178 }
1179
1180 /* Update the relevant bg descriptor fields */
1181 if (ext4_has_group_desc_csum(sb)) {
1182 int free;
1183 struct ext4_group_info *grp = NULL;
1184
1185 if (!(sbi->s_mount_state & EXT4_FC_REPLAY)) {
1186 grp = ext4_get_group_info(sb, group);
1187 if (!grp) {
1188 err = -EFSCORRUPTED;
1189 goto out;
1190 }
1191 down_read(sem: &grp->alloc_sem); /*
1192 * protect vs itable
1193 * lazyinit
1194 */
1195 }
1196 ext4_lock_group(sb, group); /* while we modify the bg desc */
1197 free = EXT4_INODES_PER_GROUP(sb) -
1198 ext4_itable_unused_count(sb, bg: gdp);
1199 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
1200 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
1201 free = 0;
1202 }
1203 /*
1204 * Check the relative inode number against the last used
1205 * relative inode number in this group. if it is greater
1206 * we need to update the bg_itable_unused count
1207 */
1208 if (ino > free)
1209 ext4_itable_unused_set(sb, bg: gdp,
1210 count: (EXT4_INODES_PER_GROUP(sb) - ino));
1211 if (!(sbi->s_mount_state & EXT4_FC_REPLAY))
1212 up_read(sem: &grp->alloc_sem);
1213 } else {
1214 ext4_lock_group(sb, group);
1215 }
1216
1217 ext4_free_inodes_set(sb, bg: gdp, count: ext4_free_inodes_count(sb, bg: gdp) - 1);
1218 if (S_ISDIR(mode)) {
1219 ext4_used_dirs_set(sb, bg: gdp, count: ext4_used_dirs_count(sb, bg: gdp) + 1);
1220 if (sbi->s_log_groups_per_flex) {
1221 ext4_group_t f = ext4_flex_group(sbi, block_group: group);
1222
1223 atomic_inc(v: &sbi_array_rcu_deref(sbi, s_flex_groups,
1224 f)->used_dirs);
1225 }
1226 }
1227 if (ext4_has_group_desc_csum(sb)) {
1228 ext4_inode_bitmap_csum_set(sb, gdp, bh: inode_bitmap_bh);
1229 ext4_group_desc_csum_set(sb, group, gdp);
1230 }
1231 ext4_unlock_group(sb, group);
1232
1233 BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
1234 err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
1235 if (err) {
1236 ext4_std_error(sb, err);
1237 goto out;
1238 }
1239
1240 percpu_counter_dec(fbc: &sbi->s_freeinodes_counter);
1241 if (S_ISDIR(mode))
1242 percpu_counter_inc(fbc: &sbi->s_dirs_counter);
1243
1244 if (sbi->s_log_groups_per_flex) {
1245 flex_group = ext4_flex_group(sbi, block_group: group);
1246 atomic_dec(v: &sbi_array_rcu_deref(sbi, s_flex_groups,
1247 flex_group)->free_inodes);
1248 }
1249
1250 inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
1251 /* This is the optimal IO size (for stat), not the fs block size */
1252 inode->i_blocks = 0;
1253 simple_inode_init_ts(inode);
1254 ei->i_crtime = inode_get_mtime(inode);
1255
1256 memset(s: ei->i_data, c: 0, n: sizeof(ei->i_data));
1257 ei->i_dir_start_lookup = 0;
1258 ei->i_disksize = 0;
1259
1260 /* Don't inherit extent flag from directory, amongst others. */
1261 ei->i_flags =
1262 ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
1263 ei->i_flags |= i_flags;
1264 ei->i_file_acl = 0;
1265 ei->i_dtime = 0;
1266 ei->i_block_group = group;
1267 ei->i_last_alloc_group = ~0;
1268
1269 ext4_set_inode_flags(inode, init: true);
1270 if (IS_DIRSYNC(inode))
1271 ext4_handle_sync(handle);
1272 if (insert_inode_locked(inode) < 0) {
1273 /*
1274 * Likely a bitmap corruption causing inode to be allocated
1275 * twice.
1276 */
1277 err = -EIO;
1278 ext4_error(sb, "failed to insert inode %lu: doubly allocated?",
1279 inode->i_ino);
1280 ext4_mark_group_bitmap_corrupted(sb, block_group: group,
1281 EXT4_GROUP_INFO_IBITMAP_CORRUPT);
1282 goto out;
1283 }
1284 inode->i_generation = get_random_u32();
1285
1286 /* Precompute checksum seed for inode metadata */
1287 if (ext4_has_feature_metadata_csum(sb)) {
1288 __u32 csum;
1289 __le32 inum = cpu_to_le32(inode->i_ino);
1290 __le32 gen = cpu_to_le32(inode->i_generation);
1291 csum = ext4_chksum(crc: sbi->s_csum_seed, address: (__u8 *)&inum,
1292 length: sizeof(inum));
1293 ei->i_csum_seed = ext4_chksum(crc: csum, address: (__u8 *)&gen, length: sizeof(gen));
1294 }
1295
1296 ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
1297 ext4_set_inode_state(inode, bit: EXT4_STATE_NEW);
1298
1299 ei->i_extra_isize = sbi->s_want_extra_isize;
1300 ei->i_inline_off = 0;
1301 if (ext4_has_feature_inline_data(sb) &&
1302 (!(ei->i_flags & (EXT4_DAX_FL|EXT4_EA_INODE_FL)) || S_ISDIR(mode)))
1303 ext4_set_inode_state(inode, bit: EXT4_STATE_MAY_INLINE_DATA);
1304 ret = inode;
1305 err = dquot_alloc_inode(inode);
1306 if (err)
1307 goto fail_drop;
1308
1309 /*
1310 * Since the encryption xattr will always be unique, create it first so
1311 * that it's less likely to end up in an external xattr block and
1312 * prevent its deduplication.
1313 */
1314 if (encrypt) {
1315 err = fscrypt_set_context(inode, fs_data: handle);
1316 if (err)
1317 goto fail_free_drop;
1318 }
1319
1320 if (!(ei->i_flags & EXT4_EA_INODE_FL)) {
1321 err = ext4_init_acl(handle, inode, dir);
1322 if (err)
1323 goto fail_free_drop;
1324
1325 err = ext4_init_security(handle, inode, dir, qstr);
1326 if (err)
1327 goto fail_free_drop;
1328 }
1329
1330 if (ext4_has_feature_extents(sb)) {
1331 /* set extent flag only for directory, file and normal symlink*/
1332 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
1333 ext4_set_inode_flag(inode, bit: EXT4_INODE_EXTENTS);
1334 ext4_ext_tree_init(handle, inode);
1335 }
1336 }
1337
1338 ext4_set_inode_mapping_order(inode);
1339
1340 ext4_update_inode_fsync_trans(handle, inode, datasync: 1);
1341
1342 err = ext4_mark_inode_dirty(handle, inode);
1343 if (err) {
1344 ext4_std_error(sb, err);
1345 goto fail_free_drop;
1346 }
1347
1348 ext4_debug("allocating inode %lu\n", inode->i_ino);
1349 trace_ext4_allocate_inode(inode, dir, mode);
1350 brelse(bh: inode_bitmap_bh);
1351 return ret;
1352
1353fail_free_drop:
1354 dquot_free_inode(inode);
1355fail_drop:
1356 clear_nlink(inode);
1357 unlock_new_inode(inode);
1358out:
1359 dquot_drop(inode);
1360 inode->i_flags |= S_NOQUOTA;
1361 iput(inode);
1362 brelse(bh: inode_bitmap_bh);
1363 return ERR_PTR(error: err);
1364}
1365
1366/* Verify that we are loading a valid orphan from disk */
1367struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
1368{
1369 unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
1370 ext4_group_t block_group;
1371 int bit;
1372 struct buffer_head *bitmap_bh = NULL;
1373 struct inode *inode = NULL;
1374 int err = -EFSCORRUPTED;
1375
1376 if (ino < EXT4_FIRST_INO(sb) || ino > max_ino)
1377 goto bad_orphan;
1378
1379 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
1380 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
1381 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
1382 if (IS_ERR(ptr: bitmap_bh))
1383 return ERR_CAST(ptr: bitmap_bh);
1384
1385 /* Having the inode bit set should be a 100% indicator that this
1386 * is a valid orphan (no e2fsck run on fs). Orphans also include
1387 * inodes that were being truncated, so we can't check i_nlink==0.
1388 */
1389 if (!ext4_test_bit(nr: bit, addr: bitmap_bh->b_data))
1390 goto bad_orphan;
1391
1392 inode = ext4_iget(sb, ino, EXT4_IGET_NORMAL);
1393 if (IS_ERR(ptr: inode)) {
1394 err = PTR_ERR(ptr: inode);
1395 ext4_error_err(sb, -err,
1396 "couldn't read orphan inode %lu (err %d)",
1397 ino, err);
1398 brelse(bh: bitmap_bh);
1399 return inode;
1400 }
1401
1402 /*
1403 * If the orphans has i_nlinks > 0 then it should be able to
1404 * be truncated, otherwise it won't be removed from the orphan
1405 * list during processing and an infinite loop will result.
1406 * Similarly, it must not be a bad inode.
1407 */
1408 if ((inode->i_nlink && !ext4_can_truncate(inode)) ||
1409 is_bad_inode(inode))
1410 goto bad_orphan;
1411
1412 if (NEXT_ORPHAN(inode) > max_ino)
1413 goto bad_orphan;
1414 brelse(bh: bitmap_bh);
1415 return inode;
1416
1417bad_orphan:
1418 ext4_error(sb, "bad orphan inode %lu", ino);
1419 if (bitmap_bh)
1420 printk(KERN_ERR "ext4_test_bit(bit=%d, block=%llu) = %d\n",
1421 bit, (unsigned long long)bitmap_bh->b_blocknr,
1422 ext4_test_bit(bit, bitmap_bh->b_data));
1423 if (inode) {
1424 printk(KERN_ERR "is_bad_inode(inode)=%d\n",
1425 is_bad_inode(inode));
1426 printk(KERN_ERR "NEXT_ORPHAN(inode)=%u\n",
1427 NEXT_ORPHAN(inode));
1428 printk(KERN_ERR "max_ino=%lu\n", max_ino);
1429 printk(KERN_ERR "i_nlink=%u\n", inode->i_nlink);
1430 /* Avoid freeing blocks if we got a bad deleted inode */
1431 if (inode->i_nlink == 0)
1432 inode->i_blocks = 0;
1433 iput(inode);
1434 }
1435 brelse(bh: bitmap_bh);
1436 return ERR_PTR(error: err);
1437}
1438
1439unsigned long ext4_count_free_inodes(struct super_block *sb)
1440{
1441 unsigned long desc_count;
1442 struct ext4_group_desc *gdp;
1443 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1444#ifdef EXT4FS_DEBUG
1445 struct ext4_super_block *es;
1446 unsigned long bitmap_count, x;
1447 struct buffer_head *bitmap_bh = NULL;
1448
1449 es = EXT4_SB(sb)->s_es;
1450 desc_count = 0;
1451 bitmap_count = 0;
1452 gdp = NULL;
1453 for (i = 0; i < ngroups; i++) {
1454 gdp = ext4_get_group_desc(sb, i, NULL);
1455 if (!gdp)
1456 continue;
1457 desc_count += ext4_free_inodes_count(sb, gdp);
1458 brelse(bitmap_bh);
1459 bitmap_bh = ext4_read_inode_bitmap(sb, i);
1460 if (IS_ERR(bitmap_bh)) {
1461 bitmap_bh = NULL;
1462 continue;
1463 }
1464
1465 x = ext4_count_free(bitmap_bh->b_data,
1466 EXT4_INODES_PER_GROUP(sb) / 8);
1467 printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
1468 (unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
1469 bitmap_count += x;
1470 }
1471 brelse(bitmap_bh);
1472 printk(KERN_DEBUG "ext4_count_free_inodes: "
1473 "stored = %u, computed = %lu, %lu\n",
1474 le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
1475 return desc_count;
1476#else
1477 desc_count = 0;
1478 for (i = 0; i < ngroups; i++) {
1479 gdp = ext4_get_group_desc(sb, block_group: i, NULL);
1480 if (!gdp)
1481 continue;
1482 desc_count += ext4_free_inodes_count(sb, bg: gdp);
1483 cond_resched();
1484 }
1485 return desc_count;
1486#endif
1487}
1488
1489/* Called at mount-time, super-block is locked */
1490unsigned long ext4_count_dirs(struct super_block * sb)
1491{
1492 unsigned long count = 0;
1493 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1494
1495 for (i = 0; i < ngroups; i++) {
1496 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, block_group: i, NULL);
1497 if (!gdp)
1498 continue;
1499 count += ext4_used_dirs_count(sb, bg: gdp);
1500 }
1501 return count;
1502}
1503
1504/*
1505 * Zeroes not yet zeroed inode table - just write zeroes through the whole
1506 * inode table. Must be called without any spinlock held. The only place
1507 * where it is called from on active part of filesystem is ext4lazyinit
1508 * thread, so we do not need any special locks, however we have to prevent
1509 * inode allocation from the current group, so we take alloc_sem lock, to
1510 * block ext4_new_inode() until we are finished.
1511 */
1512int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
1513 int barrier)
1514{
1515 struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1516 struct ext4_sb_info *sbi = EXT4_SB(sb);
1517 struct ext4_group_desc *gdp = NULL;
1518 struct buffer_head *group_desc_bh;
1519 handle_t *handle;
1520 ext4_fsblk_t blk;
1521 int num, ret = 0, used_blks = 0;
1522 unsigned long used_inos = 0;
1523
1524 gdp = ext4_get_group_desc(sb, block_group: group, bh: &group_desc_bh);
1525 if (!gdp || !grp)
1526 goto out;
1527
1528 /*
1529 * We do not need to lock this, because we are the only one
1530 * handling this flag.
1531 */
1532 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED))
1533 goto out;
1534
1535 handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
1536 if (IS_ERR(ptr: handle)) {
1537 ret = PTR_ERR(ptr: handle);
1538 goto out;
1539 }
1540
1541 down_write(sem: &grp->alloc_sem);
1542 /*
1543 * If inode bitmap was already initialized there may be some
1544 * used inodes so we need to skip blocks with used inodes in
1545 * inode table.
1546 */
1547 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT))) {
1548 used_inos = EXT4_INODES_PER_GROUP(sb) -
1549 ext4_itable_unused_count(sb, bg: gdp);
1550 used_blks = DIV_ROUND_UP(used_inos, sbi->s_inodes_per_block);
1551
1552 /* Bogus inode unused count? */
1553 if (used_blks < 0 || used_blks > sbi->s_itb_per_group) {
1554 ext4_error(sb, "Something is wrong with group %u: "
1555 "used itable blocks: %d; "
1556 "itable unused count: %u",
1557 group, used_blks,
1558 ext4_itable_unused_count(sb, gdp));
1559 ret = 1;
1560 goto err_out;
1561 }
1562
1563 used_inos += group * EXT4_INODES_PER_GROUP(sb);
1564 /*
1565 * Are there some uninitialized inodes in the inode table
1566 * before the first normal inode?
1567 */
1568 if ((used_blks != sbi->s_itb_per_group) &&
1569 (used_inos < EXT4_FIRST_INO(sb))) {
1570 ext4_error(sb, "Something is wrong with group %u: "
1571 "itable unused count: %u; "
1572 "itables initialized count: %ld",
1573 group, ext4_itable_unused_count(sb, gdp),
1574 used_inos);
1575 ret = 1;
1576 goto err_out;
1577 }
1578 }
1579
1580 blk = ext4_inode_table(sb, bg: gdp) + used_blks;
1581 num = sbi->s_itb_per_group - used_blks;
1582
1583 BUFFER_TRACE(group_desc_bh, "get_write_access");
1584 ret = ext4_journal_get_write_access(handle, sb, group_desc_bh,
1585 EXT4_JTR_NONE);
1586 if (ret)
1587 goto err_out;
1588
1589 /*
1590 * Skip zeroout if the inode table is full. But we set the ZEROED
1591 * flag anyway, because obviously, when it is full it does not need
1592 * further zeroing.
1593 */
1594 if (unlikely(num == 0))
1595 goto skip_zeroout;
1596
1597 ext4_debug("going to zero out inode table in group %d\n",
1598 group);
1599 ret = sb_issue_zeroout(sb, block: blk, nr_blocks: num, GFP_NOFS);
1600 if (ret < 0)
1601 goto err_out;
1602 if (barrier)
1603 blkdev_issue_flush(bdev: sb->s_bdev);
1604
1605skip_zeroout:
1606 ext4_lock_group(sb, group);
1607 gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED);
1608 ext4_group_desc_csum_set(sb, group, gdp);
1609 ext4_unlock_group(sb, group);
1610
1611 BUFFER_TRACE(group_desc_bh,
1612 "call ext4_handle_dirty_metadata");
1613 ret = ext4_handle_dirty_metadata(handle, NULL,
1614 group_desc_bh);
1615
1616err_out:
1617 up_write(sem: &grp->alloc_sem);
1618 ext4_journal_stop(handle);
1619out:
1620 return ret;
1621}
1622