2 * linux/fs/ext4/ialloc.c
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
9 * BSD ufs-inspired inode and directory allocation by
10 * Stephen Tweedie (sct@redhat.com), 1993
11 * Big-endian to little-endian byte-swapping/bitmaps by
12 * David S. Miller (davem@caip.rutgers.edu), 1995
15 #include <linux/time.h>
17 #include <linux/jbd2.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 <asm/byteorder.h>
28 #include "ext4_jbd2.h"
32 #include <trace/events/ext4.h>
35 * ialloc.c contains the inodes allocation and deallocation routines
39 * The free inodes are managed by bitmaps. A file system contains several
40 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
41 * block for inodes, N blocks for the inode table and data blocks.
43 * The file system contains group descriptors which are located after the
44 * super block. Each descriptor contains the number of the bitmap block and
45 * the free blocks count in the block.
49 * To avoid calling the atomic setbit hundreds or thousands of times, we only
50 * need to use it within a single byte (to ensure we get endianness right).
51 * We can use memset for the rest of the bitmap as there are no other users.
53 void ext4_mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
57 if (start_bit >= end_bit)
60 ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
61 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
62 ext4_set_bit(i, bitmap);
64 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
67 /* Initializes an uninitialized inode bitmap */
68 static unsigned ext4_init_inode_bitmap(struct super_block *sb,
69 struct buffer_head *bh,
70 ext4_group_t block_group,
71 struct ext4_group_desc *gdp)
73 J_ASSERT_BH(bh, buffer_locked(bh));
75 /* If checksum is bad mark all blocks and inodes use to prevent
76 * allocation, essentially implementing a per-group read-only flag. */
77 if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) {
78 ext4_error(sb, "Checksum bad for group %u", block_group);
79 ext4_free_group_clusters_set(sb, gdp, 0);
80 ext4_free_inodes_set(sb, gdp, 0);
81 ext4_itable_unused_set(sb, gdp, 0);
82 memset(bh->b_data, 0xff, sb->s_blocksize);
83 ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh,
84 EXT4_INODES_PER_GROUP(sb) / 8);
88 memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
89 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
91 ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh,
92 EXT4_INODES_PER_GROUP(sb) / 8);
93 ext4_group_desc_csum_set(sb, block_group, gdp);
95 return EXT4_INODES_PER_GROUP(sb);
98 void ext4_end_bitmap_read(struct buffer_head *bh, int uptodate)
101 set_buffer_uptodate(bh);
102 set_bitmap_uptodate(bh);
109 * Read the inode allocation bitmap for a given block_group, reading
110 * into the specified slot in the superblock's bitmap cache.
112 * Return buffer_head of bitmap on success or NULL.
114 static struct buffer_head *
115 ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
117 struct ext4_group_desc *desc;
118 struct buffer_head *bh = NULL;
119 ext4_fsblk_t bitmap_blk;
121 desc = ext4_get_group_desc(sb, block_group, NULL);
125 bitmap_blk = ext4_inode_bitmap(sb, desc);
126 bh = sb_getblk(sb, bitmap_blk);
128 ext4_error(sb, "Cannot read inode bitmap - "
129 "block_group = %u, inode_bitmap = %llu",
130 block_group, bitmap_blk);
133 if (bitmap_uptodate(bh))
137 if (bitmap_uptodate(bh)) {
142 ext4_lock_group(sb, block_group);
143 if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
144 ext4_init_inode_bitmap(sb, bh, block_group, desc);
145 set_bitmap_uptodate(bh);
146 set_buffer_uptodate(bh);
147 set_buffer_verified(bh);
148 ext4_unlock_group(sb, block_group);
152 ext4_unlock_group(sb, block_group);
154 if (buffer_uptodate(bh)) {
156 * if not uninit if bh is uptodate,
157 * bitmap is also uptodate
159 set_bitmap_uptodate(bh);
164 * submit the buffer_head for reading
166 trace_ext4_load_inode_bitmap(sb, block_group);
167 bh->b_end_io = ext4_end_bitmap_read;
171 if (!buffer_uptodate(bh)) {
173 ext4_error(sb, "Cannot read inode bitmap - "
174 "block_group = %u, inode_bitmap = %llu",
175 block_group, bitmap_blk);
180 ext4_lock_group(sb, block_group);
181 if (!buffer_verified(bh) &&
182 !ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh,
183 EXT4_INODES_PER_GROUP(sb) / 8)) {
184 ext4_unlock_group(sb, block_group);
186 ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
187 "inode_bitmap = %llu", block_group, bitmap_blk);
190 ext4_unlock_group(sb, block_group);
191 set_buffer_verified(bh);
196 * NOTE! When we get the inode, we're the only people
197 * that have access to it, and as such there are no
198 * race conditions we have to worry about. The inode
199 * is not on the hash-lists, and it cannot be reached
200 * through the filesystem because the directory entry
201 * has been deleted earlier.
203 * HOWEVER: we must make sure that we get no aliases,
204 * which means that we have to call "clear_inode()"
205 * _before_ we mark the inode not in use in the inode
206 * bitmaps. Otherwise a newly created file might use
207 * the same inode number (not actually the same pointer
208 * though), and then we'd have two inodes sharing the
209 * same inode number and space on the harddisk.
211 void ext4_free_inode(handle_t *handle, struct inode *inode)
213 struct super_block *sb = inode->i_sb;
216 struct buffer_head *bitmap_bh = NULL;
217 struct buffer_head *bh2;
218 ext4_group_t block_group;
220 struct ext4_group_desc *gdp;
221 struct ext4_super_block *es;
222 struct ext4_sb_info *sbi;
223 int fatal = 0, err, count, cleared;
226 printk(KERN_ERR "EXT4-fs: %s:%d: inode on "
227 "nonexistent device\n", __func__, __LINE__);
230 if (atomic_read(&inode->i_count) > 1) {
231 ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: count=%d",
232 __func__, __LINE__, inode->i_ino,
233 atomic_read(&inode->i_count));
236 if (inode->i_nlink) {
237 ext4_msg(sb, KERN_ERR, "%s:%d: inode #%lu: nlink=%d\n",
238 __func__, __LINE__, inode->i_ino, inode->i_nlink);
244 ext4_debug("freeing inode %lu\n", ino);
245 trace_ext4_free_inode(inode);
248 * Note: we must free any quota before locking the superblock,
249 * as writing the quota to disk may need the lock as well.
251 dquot_initialize(inode);
252 ext4_xattr_delete_inode(handle, inode);
253 dquot_free_inode(inode);
256 is_directory = S_ISDIR(inode->i_mode);
258 /* Do this BEFORE marking the inode not in use or returning an error */
259 ext4_clear_inode(inode);
261 es = EXT4_SB(sb)->s_es;
262 if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
263 ext4_error(sb, "reserved or nonexistent inode %lu", ino);
266 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
267 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
268 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
272 BUFFER_TRACE(bitmap_bh, "get_write_access");
273 fatal = ext4_journal_get_write_access(handle, bitmap_bh);
278 gdp = ext4_get_group_desc(sb, block_group, &bh2);
280 BUFFER_TRACE(bh2, "get_write_access");
281 fatal = ext4_journal_get_write_access(handle, bh2);
283 ext4_lock_group(sb, block_group);
284 cleared = ext4_test_and_clear_bit(bit, bitmap_bh->b_data);
285 if (fatal || !cleared) {
286 ext4_unlock_group(sb, block_group);
290 count = ext4_free_inodes_count(sb, gdp) + 1;
291 ext4_free_inodes_set(sb, gdp, count);
293 count = ext4_used_dirs_count(sb, gdp) - 1;
294 ext4_used_dirs_set(sb, gdp, count);
295 percpu_counter_dec(&sbi->s_dirs_counter);
297 ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
298 EXT4_INODES_PER_GROUP(sb) / 8);
299 ext4_group_desc_csum_set(sb, block_group, gdp);
300 ext4_unlock_group(sb, block_group);
302 percpu_counter_inc(&sbi->s_freeinodes_counter);
303 if (sbi->s_log_groups_per_flex) {
304 ext4_group_t f = ext4_flex_group(sbi, block_group);
306 atomic_inc(&sbi->s_flex_groups[f].free_inodes);
308 atomic_dec(&sbi->s_flex_groups[f].used_dirs);
310 BUFFER_TRACE(bh2, "call ext4_handle_dirty_metadata");
311 fatal = ext4_handle_dirty_metadata(handle, NULL, bh2);
314 BUFFER_TRACE(bitmap_bh, "call ext4_handle_dirty_metadata");
315 err = ext4_handle_dirty_metadata(handle, NULL, bitmap_bh);
319 ext4_error(sb, "bit already cleared for inode %lu", ino);
323 ext4_std_error(sb, fatal);
333 * Helper function for Orlov's allocator; returns critical information
334 * for a particular block group or flex_bg. If flex_size is 1, then g
335 * is a block group number; otherwise it is flex_bg number.
337 static void get_orlov_stats(struct super_block *sb, ext4_group_t g,
338 int flex_size, struct orlov_stats *stats)
340 struct ext4_group_desc *desc;
341 struct flex_groups *flex_group = EXT4_SB(sb)->s_flex_groups;
344 stats->free_inodes = atomic_read(&flex_group[g].free_inodes);
345 stats->free_clusters = atomic_read(&flex_group[g].free_clusters);
346 stats->used_dirs = atomic_read(&flex_group[g].used_dirs);
350 desc = ext4_get_group_desc(sb, g, NULL);
352 stats->free_inodes = ext4_free_inodes_count(sb, desc);
353 stats->free_clusters = ext4_free_group_clusters(sb, desc);
354 stats->used_dirs = ext4_used_dirs_count(sb, desc);
356 stats->free_inodes = 0;
357 stats->free_clusters = 0;
358 stats->used_dirs = 0;
363 * Orlov's allocator for directories.
365 * We always try to spread first-level directories.
367 * If there are blockgroups with both free inodes and free blocks counts
368 * not worse than average we return one with smallest directory count.
369 * Otherwise we simply return a random group.
371 * For the rest rules look so:
373 * It's OK to put directory into a group unless
374 * it has too many directories already (max_dirs) or
375 * it has too few free inodes left (min_inodes) or
376 * it has too few free blocks left (min_blocks) or
377 * Parent's group is preferred, if it doesn't satisfy these
378 * conditions we search cyclically through the rest. If none
379 * of the groups look good we just look for a group with more
380 * free inodes than average (starting at parent's group).
383 static int find_group_orlov(struct super_block *sb, struct inode *parent,
384 ext4_group_t *group, umode_t mode,
385 const struct qstr *qstr)
387 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
388 struct ext4_sb_info *sbi = EXT4_SB(sb);
389 ext4_group_t real_ngroups = ext4_get_groups_count(sb);
390 int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
391 unsigned int freei, avefreei, grp_free;
392 ext4_fsblk_t freeb, avefreec;
394 int max_dirs, min_inodes;
395 ext4_grpblk_t min_clusters;
396 ext4_group_t i, grp, g, ngroups;
397 struct ext4_group_desc *desc;
398 struct orlov_stats stats;
399 int flex_size = ext4_flex_bg_size(sbi);
400 struct dx_hash_info hinfo;
402 ngroups = real_ngroups;
404 ngroups = (real_ngroups + flex_size - 1) >>
405 sbi->s_log_groups_per_flex;
406 parent_group >>= sbi->s_log_groups_per_flex;
409 freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
410 avefreei = freei / ngroups;
411 freeb = EXT4_C2B(sbi,
412 percpu_counter_read_positive(&sbi->s_freeclusters_counter));
414 do_div(avefreec, ngroups);
415 ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
418 ((parent == sb->s_root->d_inode) ||
419 (ext4_test_inode_flag(parent, EXT4_INODE_TOPDIR)))) {
420 int best_ndir = inodes_per_group;
424 hinfo.hash_version = DX_HASH_HALF_MD4;
425 hinfo.seed = sbi->s_hash_seed;
426 ext4fs_dirhash(qstr->name, qstr->len, &hinfo);
429 get_random_bytes(&grp, sizeof(grp));
430 parent_group = (unsigned)grp % ngroups;
431 for (i = 0; i < ngroups; i++) {
432 g = (parent_group + i) % ngroups;
433 get_orlov_stats(sb, g, flex_size, &stats);
434 if (!stats.free_inodes)
436 if (stats.used_dirs >= best_ndir)
438 if (stats.free_inodes < avefreei)
440 if (stats.free_clusters < avefreec)
444 best_ndir = stats.used_dirs;
449 if (flex_size == 1) {
455 * We pack inodes at the beginning of the flexgroup's
456 * inode tables. Block allocation decisions will do
457 * something similar, although regular files will
458 * start at 2nd block group of the flexgroup. See
459 * ext4_ext_find_goal() and ext4_find_near().
462 for (i = 0; i < flex_size; i++) {
463 if (grp+i >= real_ngroups)
465 desc = ext4_get_group_desc(sb, grp+i, NULL);
466 if (desc && ext4_free_inodes_count(sb, desc)) {
474 max_dirs = ndirs / ngroups + inodes_per_group / 16;
475 min_inodes = avefreei - inodes_per_group*flex_size / 4;
478 min_clusters = avefreec - EXT4_CLUSTERS_PER_GROUP(sb)*flex_size / 4;
481 * Start looking in the flex group where we last allocated an
482 * inode for this parent directory
484 if (EXT4_I(parent)->i_last_alloc_group != ~0) {
485 parent_group = EXT4_I(parent)->i_last_alloc_group;
487 parent_group >>= sbi->s_log_groups_per_flex;
490 for (i = 0; i < ngroups; i++) {
491 grp = (parent_group + i) % ngroups;
492 get_orlov_stats(sb, grp, flex_size, &stats);
493 if (stats.used_dirs >= max_dirs)
495 if (stats.free_inodes < min_inodes)
497 if (stats.free_clusters < min_clusters)
503 ngroups = real_ngroups;
504 avefreei = freei / ngroups;
506 parent_group = EXT4_I(parent)->i_block_group;
507 for (i = 0; i < ngroups; i++) {
508 grp = (parent_group + i) % ngroups;
509 desc = ext4_get_group_desc(sb, grp, NULL);
511 grp_free = ext4_free_inodes_count(sb, desc);
512 if (grp_free && grp_free >= avefreei) {
521 * The free-inodes counter is approximate, and for really small
522 * filesystems the above test can fail to find any blockgroups
531 static int find_group_other(struct super_block *sb, struct inode *parent,
532 ext4_group_t *group, umode_t mode)
534 ext4_group_t parent_group = EXT4_I(parent)->i_block_group;
535 ext4_group_t i, last, ngroups = ext4_get_groups_count(sb);
536 struct ext4_group_desc *desc;
537 int flex_size = ext4_flex_bg_size(EXT4_SB(sb));
540 * Try to place the inode is the same flex group as its
541 * parent. If we can't find space, use the Orlov algorithm to
542 * find another flex group, and store that information in the
543 * parent directory's inode information so that use that flex
544 * group for future allocations.
550 parent_group &= ~(flex_size-1);
551 last = parent_group + flex_size;
554 for (i = parent_group; i < last; i++) {
555 desc = ext4_get_group_desc(sb, i, NULL);
556 if (desc && ext4_free_inodes_count(sb, desc)) {
561 if (!retry && EXT4_I(parent)->i_last_alloc_group != ~0) {
563 parent_group = EXT4_I(parent)->i_last_alloc_group;
567 * If this didn't work, use the Orlov search algorithm
568 * to find a new flex group; we pass in the mode to
569 * avoid the topdir algorithms.
571 *group = parent_group + flex_size;
572 if (*group > ngroups)
574 return find_group_orlov(sb, parent, group, mode, NULL);
578 * Try to place the inode in its parent directory
580 *group = parent_group;
581 desc = ext4_get_group_desc(sb, *group, NULL);
582 if (desc && ext4_free_inodes_count(sb, desc) &&
583 ext4_free_group_clusters(sb, desc))
587 * We're going to place this inode in a different blockgroup from its
588 * parent. We want to cause files in a common directory to all land in
589 * the same blockgroup. But we want files which are in a different
590 * directory which shares a blockgroup with our parent to land in a
591 * different blockgroup.
593 * So add our directory's i_ino into the starting point for the hash.
595 *group = (*group + parent->i_ino) % ngroups;
598 * Use a quadratic hash to find a group with a free inode and some free
601 for (i = 1; i < ngroups; i <<= 1) {
603 if (*group >= ngroups)
605 desc = ext4_get_group_desc(sb, *group, NULL);
606 if (desc && ext4_free_inodes_count(sb, desc) &&
607 ext4_free_group_clusters(sb, desc))
612 * That failed: try linear search for a free inode, even if that group
613 * has no free blocks.
615 *group = parent_group;
616 for (i = 0; i < ngroups; i++) {
617 if (++*group >= ngroups)
619 desc = ext4_get_group_desc(sb, *group, NULL);
620 if (desc && ext4_free_inodes_count(sb, desc))
628 * There are two policies for allocating an inode. If the new inode is
629 * a directory, then a forward search is made for a block group with both
630 * free space and a low directory-to-inode ratio; if that fails, then of
631 * the groups with above-average free space, that group with the fewest
632 * directories already is chosen.
634 * For other inodes, search forward from the parent directory's block
635 * group to find a free inode.
637 struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, umode_t mode,
638 const struct qstr *qstr, __u32 goal, uid_t *owner)
640 struct super_block *sb;
641 struct buffer_head *inode_bitmap_bh = NULL;
642 struct buffer_head *group_desc_bh;
643 ext4_group_t ngroups, group = 0;
644 unsigned long ino = 0;
646 struct ext4_group_desc *gdp = NULL;
647 struct ext4_inode_info *ei;
648 struct ext4_sb_info *sbi;
652 ext4_group_t flex_group;
654 /* Cannot create files in a deleted directory */
655 if (!dir || !dir->i_nlink)
656 return ERR_PTR(-EPERM);
659 ngroups = ext4_get_groups_count(sb);
660 trace_ext4_request_inode(dir, mode);
661 inode = new_inode(sb);
663 return ERR_PTR(-ENOMEM);
668 goal = sbi->s_inode_goal;
670 if (goal && goal <= le32_to_cpu(sbi->s_es->s_inodes_count)) {
671 group = (goal - 1) / EXT4_INODES_PER_GROUP(sb);
672 ino = (goal - 1) % EXT4_INODES_PER_GROUP(sb);
678 ret2 = find_group_orlov(sb, dir, &group, mode, qstr);
680 ret2 = find_group_other(sb, dir, &group, mode);
683 EXT4_I(dir)->i_last_alloc_group = group;
689 * Normally we will only go through one pass of this loop,
690 * unless we get unlucky and it turns out the group we selected
691 * had its last inode grabbed by someone else.
693 for (i = 0; i < ngroups; i++, ino = 0) {
696 gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
700 brelse(inode_bitmap_bh);
701 inode_bitmap_bh = ext4_read_inode_bitmap(sb, group);
702 if (!inode_bitmap_bh)
705 repeat_in_this_group:
706 ino = ext4_find_next_zero_bit((unsigned long *)
707 inode_bitmap_bh->b_data,
708 EXT4_INODES_PER_GROUP(sb), ino);
709 if (ino >= EXT4_INODES_PER_GROUP(sb)) {
710 if (++group == ngroups)
714 if (group == 0 && (ino+1) < EXT4_FIRST_INO(sb)) {
715 ext4_error(sb, "reserved inode found cleared - "
716 "inode=%lu", ino + 1);
719 ext4_lock_group(sb, group);
720 ret2 = ext4_test_and_set_bit(ino, inode_bitmap_bh->b_data);
721 ext4_unlock_group(sb, group);
722 ino++; /* the inode bitmap is zero-based */
724 goto got; /* we grabbed the inode! */
725 if (ino < EXT4_INODES_PER_GROUP(sb))
726 goto repeat_in_this_group;
732 /* We may have to initialize the block bitmap if it isn't already */
733 if (ext4_has_group_desc_csum(sb) &&
734 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
735 struct buffer_head *block_bitmap_bh;
737 block_bitmap_bh = ext4_read_block_bitmap(sb, group);
738 BUFFER_TRACE(block_bitmap_bh, "get block bitmap access");
739 err = ext4_journal_get_write_access(handle, block_bitmap_bh);
741 brelse(block_bitmap_bh);
745 BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap");
746 err = ext4_handle_dirty_metadata(handle, NULL, block_bitmap_bh);
747 brelse(block_bitmap_bh);
749 /* recheck and clear flag under lock if we still need to */
750 ext4_lock_group(sb, group);
751 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
752 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT);
753 ext4_free_group_clusters_set(sb, gdp,
754 ext4_free_clusters_after_init(sb, group, gdp));
755 ext4_block_bitmap_csum_set(sb, group, gdp,
757 EXT4_BLOCKS_PER_GROUP(sb) /
759 ext4_group_desc_csum_set(sb, group, gdp);
761 ext4_unlock_group(sb, group);
767 BUFFER_TRACE(inode_bitmap_bh, "get_write_access");
768 err = ext4_journal_get_write_access(handle, inode_bitmap_bh);
772 BUFFER_TRACE(group_desc_bh, "get_write_access");
773 err = ext4_journal_get_write_access(handle, group_desc_bh);
777 /* Update the relevant bg descriptor fields */
778 if (ext4_has_group_desc_csum(sb)) {
780 struct ext4_group_info *grp = ext4_get_group_info(sb, group);
782 down_read(&grp->alloc_sem); /* protect vs itable lazyinit */
783 ext4_lock_group(sb, group); /* while we modify the bg desc */
784 free = EXT4_INODES_PER_GROUP(sb) -
785 ext4_itable_unused_count(sb, gdp);
786 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) {
787 gdp->bg_flags &= cpu_to_le16(~EXT4_BG_INODE_UNINIT);
791 * Check the relative inode number against the last used
792 * relative inode number in this group. if it is greater
793 * we need to update the bg_itable_unused count
796 ext4_itable_unused_set(sb, gdp,
797 (EXT4_INODES_PER_GROUP(sb) - ino));
798 up_read(&grp->alloc_sem);
800 ext4_lock_group(sb, group);
803 ext4_free_inodes_set(sb, gdp, ext4_free_inodes_count(sb, gdp) - 1);
805 ext4_used_dirs_set(sb, gdp, ext4_used_dirs_count(sb, gdp) + 1);
806 if (sbi->s_log_groups_per_flex) {
807 ext4_group_t f = ext4_flex_group(sbi, group);
809 atomic_inc(&sbi->s_flex_groups[f].used_dirs);
812 if (ext4_has_group_desc_csum(sb)) {
813 ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh,
814 EXT4_INODES_PER_GROUP(sb) / 8);
815 ext4_group_desc_csum_set(sb, group, gdp);
817 ext4_unlock_group(sb, group);
819 BUFFER_TRACE(inode_bitmap_bh, "call ext4_handle_dirty_metadata");
820 err = ext4_handle_dirty_metadata(handle, NULL, inode_bitmap_bh);
824 BUFFER_TRACE(group_desc_bh, "call ext4_handle_dirty_metadata");
825 err = ext4_handle_dirty_metadata(handle, NULL, group_desc_bh);
829 percpu_counter_dec(&sbi->s_freeinodes_counter);
831 percpu_counter_inc(&sbi->s_dirs_counter);
833 if (sbi->s_log_groups_per_flex) {
834 flex_group = ext4_flex_group(sbi, group);
835 atomic_dec(&sbi->s_flex_groups[flex_group].free_inodes);
838 inode->i_mode = mode;
839 i_uid_write(inode, owner[0]);
840 i_gid_write(inode, owner[1]);
841 } else if (test_opt(sb, GRPID)) {
842 inode->i_mode = mode;
843 inode->i_uid = current_fsuid();
844 inode->i_gid = dir->i_gid;
846 inode_init_owner(inode, dir, mode);
848 inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
849 /* This is the optimal IO size (for stat), not the fs block size */
851 inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
852 ext4_current_time(inode);
854 memset(ei->i_data, 0, sizeof(ei->i_data));
855 ei->i_dir_start_lookup = 0;
858 /* Don't inherit extent flag from directory, amongst others. */
860 ext4_mask_flags(mode, EXT4_I(dir)->i_flags & EXT4_FL_INHERITED);
863 ei->i_block_group = group;
864 ei->i_last_alloc_group = ~0;
866 ext4_set_inode_flags(inode);
867 if (IS_DIRSYNC(inode))
868 ext4_handle_sync(handle);
869 if (insert_inode_locked(inode) < 0) {
871 * Likely a bitmap corruption causing inode to be allocated
877 spin_lock(&sbi->s_next_gen_lock);
878 inode->i_generation = sbi->s_next_generation++;
879 spin_unlock(&sbi->s_next_gen_lock);
881 /* Precompute checksum seed for inode metadata */
882 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
883 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
885 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
886 __le32 inum = cpu_to_le32(inode->i_ino);
887 __le32 gen = cpu_to_le32(inode->i_generation);
888 csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
890 ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
894 ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
895 ext4_set_inode_state(inode, EXT4_STATE_NEW);
897 ei->i_extra_isize = EXT4_SB(sb)->s_want_extra_isize;
900 dquot_initialize(inode);
901 err = dquot_alloc_inode(inode);
905 err = ext4_init_acl(handle, inode, dir);
909 err = ext4_init_security(handle, inode, dir, qstr);
913 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
914 /* set extent flag only for directory, file and normal symlink*/
915 if (S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode)) {
916 ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
917 ext4_ext_tree_init(handle, inode);
921 if (ext4_handle_valid(handle)) {
922 ei->i_sync_tid = handle->h_transaction->t_tid;
923 ei->i_datasync_tid = handle->h_transaction->t_tid;
926 err = ext4_mark_inode_dirty(handle, inode);
928 ext4_std_error(sb, err);
932 ext4_debug("allocating inode %lu\n", inode->i_ino);
933 trace_ext4_allocate_inode(inode, dir, mode);
936 ext4_std_error(sb, err);
941 brelse(inode_bitmap_bh);
945 dquot_free_inode(inode);
949 inode->i_flags |= S_NOQUOTA;
951 unlock_new_inode(inode);
953 brelse(inode_bitmap_bh);
957 /* Verify that we are loading a valid orphan from disk */
958 struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
960 unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
961 ext4_group_t block_group;
963 struct buffer_head *bitmap_bh;
964 struct inode *inode = NULL;
967 /* Error cases - e2fsck has already cleaned up for us */
969 ext4_warning(sb, "bad orphan ino %lu! e2fsck was run?", ino);
973 block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
974 bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
975 bitmap_bh = ext4_read_inode_bitmap(sb, block_group);
977 ext4_warning(sb, "inode bitmap error for orphan %lu", ino);
981 /* Having the inode bit set should be a 100% indicator that this
982 * is a valid orphan (no e2fsck run on fs). Orphans also include
983 * inodes that were being truncated, so we can't check i_nlink==0.
985 if (!ext4_test_bit(bit, bitmap_bh->b_data))
988 inode = ext4_iget(sb, ino);
993 * If the orphans has i_nlinks > 0 then it should be able to be
994 * truncated, otherwise it won't be removed from the orphan list
995 * during processing and an infinite loop will result.
997 if (inode->i_nlink && !ext4_can_truncate(inode))
1000 if (NEXT_ORPHAN(inode) > max_ino)
1006 err = PTR_ERR(inode);
1009 ext4_warning(sb, "bad orphan inode %lu! e2fsck was run?", ino);
1010 printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n",
1011 bit, (unsigned long long)bitmap_bh->b_blocknr,
1012 ext4_test_bit(bit, bitmap_bh->b_data));
1013 printk(KERN_NOTICE "inode=%p\n", inode);
1015 printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
1016 is_bad_inode(inode));
1017 printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
1018 NEXT_ORPHAN(inode));
1019 printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
1020 printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
1021 /* Avoid freeing blocks if we got a bad deleted inode */
1022 if (inode->i_nlink == 0)
1023 inode->i_blocks = 0;
1028 return ERR_PTR(err);
1031 unsigned long ext4_count_free_inodes(struct super_block *sb)
1033 unsigned long desc_count;
1034 struct ext4_group_desc *gdp;
1035 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1037 struct ext4_super_block *es;
1038 unsigned long bitmap_count, x;
1039 struct buffer_head *bitmap_bh = NULL;
1041 es = EXT4_SB(sb)->s_es;
1045 for (i = 0; i < ngroups; i++) {
1046 gdp = ext4_get_group_desc(sb, i, NULL);
1049 desc_count += ext4_free_inodes_count(sb, gdp);
1051 bitmap_bh = ext4_read_inode_bitmap(sb, i);
1055 x = ext4_count_free(bitmap_bh->b_data,
1056 EXT4_INODES_PER_GROUP(sb) / 8);
1057 printk(KERN_DEBUG "group %lu: stored = %d, counted = %lu\n",
1058 (unsigned long) i, ext4_free_inodes_count(sb, gdp), x);
1062 printk(KERN_DEBUG "ext4_count_free_inodes: "
1063 "stored = %u, computed = %lu, %lu\n",
1064 le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
1068 for (i = 0; i < ngroups; i++) {
1069 gdp = ext4_get_group_desc(sb, i, NULL);
1072 desc_count += ext4_free_inodes_count(sb, gdp);
1079 /* Called at mount-time, super-block is locked */
1080 unsigned long ext4_count_dirs(struct super_block * sb)
1082 unsigned long count = 0;
1083 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
1085 for (i = 0; i < ngroups; i++) {
1086 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1089 count += ext4_used_dirs_count(sb, gdp);
1095 * Zeroes not yet zeroed inode table - just write zeroes through the whole
1096 * inode table. Must be called without any spinlock held. The only place
1097 * where it is called from on active part of filesystem is ext4lazyinit
1098 * thread, so we do not need any special locks, however we have to prevent
1099 * inode allocation from the current group, so we take alloc_sem lock, to
1100 * block ext4_new_inode() until we are finished.
1102 int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
1105 struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1106 struct ext4_sb_info *sbi = EXT4_SB(sb);
1107 struct ext4_group_desc *gdp = NULL;
1108 struct buffer_head *group_desc_bh;
1111 int num, ret = 0, used_blks = 0;
1113 /* This should not happen, but just to be sure check this */
1114 if (sb->s_flags & MS_RDONLY) {
1119 gdp = ext4_get_group_desc(sb, group, &group_desc_bh);
1124 * We do not need to lock this, because we are the only one
1125 * handling this flag.
1127 if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED))
1130 handle = ext4_journal_start_sb(sb, 1);
1131 if (IS_ERR(handle)) {
1132 ret = PTR_ERR(handle);
1136 down_write(&grp->alloc_sem);
1138 * If inode bitmap was already initialized there may be some
1139 * used inodes so we need to skip blocks with used inodes in
1142 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)))
1143 used_blks = DIV_ROUND_UP((EXT4_INODES_PER_GROUP(sb) -
1144 ext4_itable_unused_count(sb, gdp)),
1145 sbi->s_inodes_per_block);
1147 if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group)) {
1148 ext4_error(sb, "Something is wrong with group %u: "
1149 "used itable blocks: %d; "
1150 "itable unused count: %u",
1152 ext4_itable_unused_count(sb, gdp));
1157 blk = ext4_inode_table(sb, gdp) + used_blks;
1158 num = sbi->s_itb_per_group - used_blks;
1160 BUFFER_TRACE(group_desc_bh, "get_write_access");
1161 ret = ext4_journal_get_write_access(handle,
1167 * Skip zeroout if the inode table is full. But we set the ZEROED
1168 * flag anyway, because obviously, when it is full it does not need
1171 if (unlikely(num == 0))
1174 ext4_debug("going to zero out inode table in group %d\n",
1176 ret = sb_issue_zeroout(sb, blk, num, GFP_NOFS);
1180 blkdev_issue_flush(sb->s_bdev, GFP_NOFS, NULL);
1183 ext4_lock_group(sb, group);
1184 gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED);
1185 ext4_group_desc_csum_set(sb, group, gdp);
1186 ext4_unlock_group(sb, group);
1188 BUFFER_TRACE(group_desc_bh,
1189 "call ext4_handle_dirty_metadata");
1190 ret = ext4_handle_dirty_metadata(handle, NULL,
1194 up_write(&grp->alloc_sem);
1195 ext4_journal_stop(handle);