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/stat.h>
18 #include <linux/string.h>
19 #include <linux/quotaops.h>
20 #include <linux/buffer_head.h>
21 #include <linux/random.h>
22 #include <linux/bitops.h>
23 #include <linux/blkdev.h>
24 #include <asm/byteorder.h>
27 #include "ext4_jbd2.h"
31 #include <trace/events/ext4.h>
34 * ialloc.c contains the inodes allocation and deallocation routines
38 * The free inodes are managed by bitmaps. A file system contains several
39 * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
40 * block for inodes, N blocks for the inode table and data blocks.
42 * The file system contains group descriptors which are located after the
43 * super block. Each descriptor contains the number of the bitmap block and
44 * the free blocks count in the block.
48 * To avoid calling the atomic setbit hundreds or thousands of times, we only
49 * need to use it within a single byte (to ensure we get endianness right).
50 * We can use memset for the rest of the bitmap as there are no other users.
52 void ext4_mark_bitmap_end(int start_bit
, int end_bit
, char *bitmap
)
56 if (start_bit
>= end_bit
)
59 ext4_debug("mark end bits +%d through +%d used\n", start_bit
, end_bit
);
60 for (i
= start_bit
; i
< ((start_bit
+ 7) & ~7UL); i
++)
61 ext4_set_bit(i
, bitmap
);
63 memset(bitmap
+ (i
>> 3), 0xff, (end_bit
- i
) >> 3);
66 /* Initializes an uninitialized inode bitmap */
67 static int ext4_init_inode_bitmap(struct super_block
*sb
,
68 struct buffer_head
*bh
,
69 ext4_group_t block_group
,
70 struct ext4_group_desc
*gdp
)
72 struct ext4_group_info
*grp
;
73 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
74 J_ASSERT_BH(bh
, buffer_locked(bh
));
76 /* If checksum is bad mark all blocks and inodes use to prevent
77 * allocation, essentially implementing a per-group read-only flag. */
78 if (!ext4_group_desc_csum_verify(sb
, block_group
, gdp
)) {
79 grp
= ext4_get_group_info(sb
, block_group
);
80 if (!EXT4_MB_GRP_BBITMAP_CORRUPT(grp
))
81 percpu_counter_sub(&sbi
->s_freeclusters_counter
,
83 set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT
, &grp
->bb_state
);
84 if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp
)) {
86 count
= ext4_free_inodes_count(sb
, gdp
);
87 percpu_counter_sub(&sbi
->s_freeinodes_counter
,
90 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT
, &grp
->bb_state
);
94 memset(bh
->b_data
, 0, (EXT4_INODES_PER_GROUP(sb
) + 7) / 8);
95 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb
), sb
->s_blocksize
* 8,
97 ext4_inode_bitmap_csum_set(sb
, block_group
, gdp
, bh
,
98 EXT4_INODES_PER_GROUP(sb
) / 8);
99 ext4_group_desc_csum_set(sb
, block_group
, gdp
);
104 void ext4_end_bitmap_read(struct buffer_head
*bh
, int uptodate
)
107 set_buffer_uptodate(bh
);
108 set_bitmap_uptodate(bh
);
114 static int ext4_validate_inode_bitmap(struct super_block
*sb
,
115 struct ext4_group_desc
*desc
,
116 ext4_group_t block_group
,
117 struct buffer_head
*bh
)
120 struct ext4_group_info
*grp
= ext4_get_group_info(sb
, block_group
);
121 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
123 if (buffer_verified(bh
))
125 if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp
))
126 return -EFSCORRUPTED
;
128 ext4_lock_group(sb
, block_group
);
129 blk
= ext4_inode_bitmap(sb
, desc
);
130 if (!ext4_inode_bitmap_csum_verify(sb
, block_group
, desc
, bh
,
131 EXT4_INODES_PER_GROUP(sb
) / 8)) {
132 ext4_unlock_group(sb
, block_group
);
133 ext4_error(sb
, "Corrupt inode bitmap - block_group = %u, "
134 "inode_bitmap = %llu", block_group
, blk
);
135 grp
= ext4_get_group_info(sb
, block_group
);
136 if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp
)) {
138 count
= ext4_free_inodes_count(sb
, desc
);
139 percpu_counter_sub(&sbi
->s_freeinodes_counter
,
142 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT
, &grp
->bb_state
);
145 set_buffer_verified(bh
);
146 ext4_unlock_group(sb
, block_group
);
151 * Read the inode allocation bitmap for a given block_group, reading
152 * into the specified slot in the superblock's bitmap cache.
154 * Return buffer_head of bitmap on success or NULL.
156 static struct buffer_head
*
157 ext4_read_inode_bitmap(struct super_block
*sb
, ext4_group_t block_group
)
159 struct ext4_group_desc
*desc
;
160 struct buffer_head
*bh
= NULL
;
161 ext4_fsblk_t bitmap_blk
;
164 desc
= ext4_get_group_desc(sb
, block_group
, NULL
);
166 return ERR_PTR(-EFSCORRUPTED
);
168 bitmap_blk
= ext4_inode_bitmap(sb
, desc
);
169 bh
= sb_getblk(sb
, bitmap_blk
);
171 ext4_error(sb
, "Cannot read inode bitmap - "
172 "block_group = %u, inode_bitmap = %llu",
173 block_group
, bitmap_blk
);
174 return ERR_PTR(-EIO
);
176 if (bitmap_uptodate(bh
))
180 if (bitmap_uptodate(bh
)) {
185 ext4_lock_group(sb
, block_group
);
186 if (desc
->bg_flags
& cpu_to_le16(EXT4_BG_INODE_UNINIT
)) {
187 err
= ext4_init_inode_bitmap(sb
, bh
, block_group
, desc
);
188 set_bitmap_uptodate(bh
);
189 set_buffer_uptodate(bh
);
190 set_buffer_verified(bh
);
191 ext4_unlock_group(sb
, block_group
);
194 ext4_error(sb
, "Failed to init inode bitmap for group "
195 "%u: %d", block_group
, err
);
200 ext4_unlock_group(sb
, block_group
);
202 if (buffer_uptodate(bh
)) {
204 * if not uninit if bh is uptodate,
205 * bitmap is also uptodate
207 set_bitmap_uptodate(bh
);
212 * submit the buffer_head for reading
214 trace_ext4_load_inode_bitmap(sb
, block_group
);
215 bh
->b_end_io
= ext4_end_bitmap_read
;
217 submit_bh(READ
| REQ_META
| REQ_PRIO
, bh
);
219 if (!buffer_uptodate(bh
)) {
221 ext4_error(sb
, "Cannot read inode bitmap - "
222 "block_group = %u, inode_bitmap = %llu",
223 block_group
, bitmap_blk
);
224 return ERR_PTR(-EIO
);
228 err
= ext4_validate_inode_bitmap(sb
, desc
, block_group
, bh
);
238 * NOTE! When we get the inode, we're the only people
239 * that have access to it, and as such there are no
240 * race conditions we have to worry about. The inode
241 * is not on the hash-lists, and it cannot be reached
242 * through the filesystem because the directory entry
243 * has been deleted earlier.
245 * HOWEVER: we must make sure that we get no aliases,
246 * which means that we have to call "clear_inode()"
247 * _before_ we mark the inode not in use in the inode
248 * bitmaps. Otherwise a newly created file might use
249 * the same inode number (not actually the same pointer
250 * though), and then we'd have two inodes sharing the
251 * same inode number and space on the harddisk.
253 void ext4_free_inode(handle_t
*handle
, struct inode
*inode
)
255 struct super_block
*sb
= inode
->i_sb
;
258 struct buffer_head
*bitmap_bh
= NULL
;
259 struct buffer_head
*bh2
;
260 ext4_group_t block_group
;
262 struct ext4_group_desc
*gdp
;
263 struct ext4_super_block
*es
;
264 struct ext4_sb_info
*sbi
;
265 int fatal
= 0, err
, count
, cleared
;
266 struct ext4_group_info
*grp
;
269 printk(KERN_ERR
"EXT4-fs: %s:%d: inode on "
270 "nonexistent device\n", __func__
, __LINE__
);
273 if (atomic_read(&inode
->i_count
) > 1) {
274 ext4_msg(sb
, KERN_ERR
, "%s:%d: inode #%lu: count=%d",
275 __func__
, __LINE__
, inode
->i_ino
,
276 atomic_read(&inode
->i_count
));
279 if (inode
->i_nlink
) {
280 ext4_msg(sb
, KERN_ERR
, "%s:%d: inode #%lu: nlink=%d\n",
281 __func__
, __LINE__
, inode
->i_ino
, inode
->i_nlink
);
287 ext4_debug("freeing inode %lu\n", ino
);
288 trace_ext4_free_inode(inode
);
291 * Note: we must free any quota before locking the superblock,
292 * as writing the quota to disk may need the lock as well.
294 dquot_initialize(inode
);
295 ext4_xattr_delete_inode(handle
, inode
);
296 dquot_free_inode(inode
);
299 is_directory
= S_ISDIR(inode
->i_mode
);
301 /* Do this BEFORE marking the inode not in use or returning an error */
302 ext4_clear_inode(inode
);
304 es
= EXT4_SB(sb
)->s_es
;
305 if (ino
< EXT4_FIRST_INO(sb
) || ino
> le32_to_cpu(es
->s_inodes_count
)) {
306 ext4_error(sb
, "reserved or nonexistent inode %lu", ino
);
309 block_group
= (ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
310 bit
= (ino
- 1) % EXT4_INODES_PER_GROUP(sb
);
311 bitmap_bh
= ext4_read_inode_bitmap(sb
, block_group
);
312 /* Don't bother if the inode bitmap is corrupt. */
313 grp
= ext4_get_group_info(sb
, block_group
);
314 if (IS_ERR(bitmap_bh
)) {
315 fatal
= PTR_ERR(bitmap_bh
);
319 if (unlikely(EXT4_MB_GRP_IBITMAP_CORRUPT(grp
))) {
320 fatal
= -EFSCORRUPTED
;
324 BUFFER_TRACE(bitmap_bh
, "get_write_access");
325 fatal
= ext4_journal_get_write_access(handle
, bitmap_bh
);
330 gdp
= ext4_get_group_desc(sb
, block_group
, &bh2
);
332 BUFFER_TRACE(bh2
, "get_write_access");
333 fatal
= ext4_journal_get_write_access(handle
, bh2
);
335 ext4_lock_group(sb
, block_group
);
336 cleared
= ext4_test_and_clear_bit(bit
, bitmap_bh
->b_data
);
337 if (fatal
|| !cleared
) {
338 ext4_unlock_group(sb
, block_group
);
342 count
= ext4_free_inodes_count(sb
, gdp
) + 1;
343 ext4_free_inodes_set(sb
, gdp
, count
);
345 count
= ext4_used_dirs_count(sb
, gdp
) - 1;
346 ext4_used_dirs_set(sb
, gdp
, count
);
347 percpu_counter_dec(&sbi
->s_dirs_counter
);
349 ext4_inode_bitmap_csum_set(sb
, block_group
, gdp
, bitmap_bh
,
350 EXT4_INODES_PER_GROUP(sb
) / 8);
351 ext4_group_desc_csum_set(sb
, block_group
, gdp
);
352 ext4_unlock_group(sb
, block_group
);
354 percpu_counter_inc(&sbi
->s_freeinodes_counter
);
355 if (sbi
->s_log_groups_per_flex
) {
356 ext4_group_t f
= ext4_flex_group(sbi
, block_group
);
358 atomic_inc(&sbi
->s_flex_groups
[f
].free_inodes
);
360 atomic_dec(&sbi
->s_flex_groups
[f
].used_dirs
);
362 BUFFER_TRACE(bh2
, "call ext4_handle_dirty_metadata");
363 fatal
= ext4_handle_dirty_metadata(handle
, NULL
, bh2
);
366 BUFFER_TRACE(bitmap_bh
, "call ext4_handle_dirty_metadata");
367 err
= ext4_handle_dirty_metadata(handle
, NULL
, bitmap_bh
);
371 ext4_error(sb
, "bit already cleared for inode %lu", ino
);
372 if (gdp
&& !EXT4_MB_GRP_IBITMAP_CORRUPT(grp
)) {
374 count
= ext4_free_inodes_count(sb
, gdp
);
375 percpu_counter_sub(&sbi
->s_freeinodes_counter
,
378 set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT
, &grp
->bb_state
);
383 ext4_std_error(sb
, fatal
);
393 * Helper function for Orlov's allocator; returns critical information
394 * for a particular block group or flex_bg. If flex_size is 1, then g
395 * is a block group number; otherwise it is flex_bg number.
397 static void get_orlov_stats(struct super_block
*sb
, ext4_group_t g
,
398 int flex_size
, struct orlov_stats
*stats
)
400 struct ext4_group_desc
*desc
;
401 struct flex_groups
*flex_group
= EXT4_SB(sb
)->s_flex_groups
;
404 stats
->free_inodes
= atomic_read(&flex_group
[g
].free_inodes
);
405 stats
->free_clusters
= atomic64_read(&flex_group
[g
].free_clusters
);
406 stats
->used_dirs
= atomic_read(&flex_group
[g
].used_dirs
);
410 desc
= ext4_get_group_desc(sb
, g
, NULL
);
412 stats
->free_inodes
= ext4_free_inodes_count(sb
, desc
);
413 stats
->free_clusters
= ext4_free_group_clusters(sb
, desc
);
414 stats
->used_dirs
= ext4_used_dirs_count(sb
, desc
);
416 stats
->free_inodes
= 0;
417 stats
->free_clusters
= 0;
418 stats
->used_dirs
= 0;
423 * Orlov's allocator for directories.
425 * We always try to spread first-level directories.
427 * If there are blockgroups with both free inodes and free blocks counts
428 * not worse than average we return one with smallest directory count.
429 * Otherwise we simply return a random group.
431 * For the rest rules look so:
433 * It's OK to put directory into a group unless
434 * it has too many directories already (max_dirs) or
435 * it has too few free inodes left (min_inodes) or
436 * it has too few free blocks left (min_blocks) or
437 * Parent's group is preferred, if it doesn't satisfy these
438 * conditions we search cyclically through the rest. If none
439 * of the groups look good we just look for a group with more
440 * free inodes than average (starting at parent's group).
443 static int find_group_orlov(struct super_block
*sb
, struct inode
*parent
,
444 ext4_group_t
*group
, umode_t mode
,
445 const struct qstr
*qstr
)
447 ext4_group_t parent_group
= EXT4_I(parent
)->i_block_group
;
448 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
449 ext4_group_t real_ngroups
= ext4_get_groups_count(sb
);
450 int inodes_per_group
= EXT4_INODES_PER_GROUP(sb
);
451 unsigned int freei
, avefreei
, grp_free
;
452 ext4_fsblk_t freeb
, avefreec
;
454 int max_dirs
, min_inodes
;
455 ext4_grpblk_t min_clusters
;
456 ext4_group_t i
, grp
, g
, ngroups
;
457 struct ext4_group_desc
*desc
;
458 struct orlov_stats stats
;
459 int flex_size
= ext4_flex_bg_size(sbi
);
460 struct dx_hash_info hinfo
;
462 ngroups
= real_ngroups
;
464 ngroups
= (real_ngroups
+ flex_size
- 1) >>
465 sbi
->s_log_groups_per_flex
;
466 parent_group
>>= sbi
->s_log_groups_per_flex
;
469 freei
= percpu_counter_read_positive(&sbi
->s_freeinodes_counter
);
470 avefreei
= freei
/ ngroups
;
471 freeb
= EXT4_C2B(sbi
,
472 percpu_counter_read_positive(&sbi
->s_freeclusters_counter
));
474 do_div(avefreec
, ngroups
);
475 ndirs
= percpu_counter_read_positive(&sbi
->s_dirs_counter
);
478 ((parent
== d_inode(sb
->s_root
)) ||
479 (ext4_test_inode_flag(parent
, EXT4_INODE_TOPDIR
)))) {
480 int best_ndir
= inodes_per_group
;
484 hinfo
.hash_version
= DX_HASH_HALF_MD4
;
485 hinfo
.seed
= sbi
->s_hash_seed
;
486 ext4fs_dirhash(qstr
->name
, qstr
->len
, &hinfo
);
490 parent_group
= (unsigned)grp
% ngroups
;
491 for (i
= 0; i
< ngroups
; i
++) {
492 g
= (parent_group
+ i
) % ngroups
;
493 get_orlov_stats(sb
, g
, flex_size
, &stats
);
494 if (!stats
.free_inodes
)
496 if (stats
.used_dirs
>= best_ndir
)
498 if (stats
.free_inodes
< avefreei
)
500 if (stats
.free_clusters
< avefreec
)
504 best_ndir
= stats
.used_dirs
;
509 if (flex_size
== 1) {
515 * We pack inodes at the beginning of the flexgroup's
516 * inode tables. Block allocation decisions will do
517 * something similar, although regular files will
518 * start at 2nd block group of the flexgroup. See
519 * ext4_ext_find_goal() and ext4_find_near().
522 for (i
= 0; i
< flex_size
; i
++) {
523 if (grp
+i
>= real_ngroups
)
525 desc
= ext4_get_group_desc(sb
, grp
+i
, NULL
);
526 if (desc
&& ext4_free_inodes_count(sb
, desc
)) {
534 max_dirs
= ndirs
/ ngroups
+ inodes_per_group
/ 16;
535 min_inodes
= avefreei
- inodes_per_group
*flex_size
/ 4;
538 min_clusters
= avefreec
- EXT4_CLUSTERS_PER_GROUP(sb
)*flex_size
/ 4;
541 * Start looking in the flex group where we last allocated an
542 * inode for this parent directory
544 if (EXT4_I(parent
)->i_last_alloc_group
!= ~0) {
545 parent_group
= EXT4_I(parent
)->i_last_alloc_group
;
547 parent_group
>>= sbi
->s_log_groups_per_flex
;
550 for (i
= 0; i
< ngroups
; i
++) {
551 grp
= (parent_group
+ i
) % ngroups
;
552 get_orlov_stats(sb
, grp
, flex_size
, &stats
);
553 if (stats
.used_dirs
>= max_dirs
)
555 if (stats
.free_inodes
< min_inodes
)
557 if (stats
.free_clusters
< min_clusters
)
563 ngroups
= real_ngroups
;
564 avefreei
= freei
/ ngroups
;
566 parent_group
= EXT4_I(parent
)->i_block_group
;
567 for (i
= 0; i
< ngroups
; i
++) {
568 grp
= (parent_group
+ i
) % ngroups
;
569 desc
= ext4_get_group_desc(sb
, grp
, NULL
);
571 grp_free
= ext4_free_inodes_count(sb
, desc
);
572 if (grp_free
&& grp_free
>= avefreei
) {
581 * The free-inodes counter is approximate, and for really small
582 * filesystems the above test can fail to find any blockgroups
591 static int find_group_other(struct super_block
*sb
, struct inode
*parent
,
592 ext4_group_t
*group
, umode_t mode
)
594 ext4_group_t parent_group
= EXT4_I(parent
)->i_block_group
;
595 ext4_group_t i
, last
, ngroups
= ext4_get_groups_count(sb
);
596 struct ext4_group_desc
*desc
;
597 int flex_size
= ext4_flex_bg_size(EXT4_SB(sb
));
600 * Try to place the inode is the same flex group as its
601 * parent. If we can't find space, use the Orlov algorithm to
602 * find another flex group, and store that information in the
603 * parent directory's inode information so that use that flex
604 * group for future allocations.
610 parent_group
&= ~(flex_size
-1);
611 last
= parent_group
+ flex_size
;
614 for (i
= parent_group
; i
< last
; i
++) {
615 desc
= ext4_get_group_desc(sb
, i
, NULL
);
616 if (desc
&& ext4_free_inodes_count(sb
, desc
)) {
621 if (!retry
&& EXT4_I(parent
)->i_last_alloc_group
!= ~0) {
623 parent_group
= EXT4_I(parent
)->i_last_alloc_group
;
627 * If this didn't work, use the Orlov search algorithm
628 * to find a new flex group; we pass in the mode to
629 * avoid the topdir algorithms.
631 *group
= parent_group
+ flex_size
;
632 if (*group
> ngroups
)
634 return find_group_orlov(sb
, parent
, group
, mode
, NULL
);
638 * Try to place the inode in its parent directory
640 *group
= parent_group
;
641 desc
= ext4_get_group_desc(sb
, *group
, NULL
);
642 if (desc
&& ext4_free_inodes_count(sb
, desc
) &&
643 ext4_free_group_clusters(sb
, desc
))
647 * We're going to place this inode in a different blockgroup from its
648 * parent. We want to cause files in a common directory to all land in
649 * the same blockgroup. But we want files which are in a different
650 * directory which shares a blockgroup with our parent to land in a
651 * different blockgroup.
653 * So add our directory's i_ino into the starting point for the hash.
655 *group
= (*group
+ parent
->i_ino
) % ngroups
;
658 * Use a quadratic hash to find a group with a free inode and some free
661 for (i
= 1; i
< ngroups
; i
<<= 1) {
663 if (*group
>= ngroups
)
665 desc
= ext4_get_group_desc(sb
, *group
, NULL
);
666 if (desc
&& ext4_free_inodes_count(sb
, desc
) &&
667 ext4_free_group_clusters(sb
, desc
))
672 * That failed: try linear search for a free inode, even if that group
673 * has no free blocks.
675 *group
= parent_group
;
676 for (i
= 0; i
< ngroups
; i
++) {
677 if (++*group
>= ngroups
)
679 desc
= ext4_get_group_desc(sb
, *group
, NULL
);
680 if (desc
&& ext4_free_inodes_count(sb
, desc
))
688 * In no journal mode, if an inode has recently been deleted, we want
689 * to avoid reusing it until we're reasonably sure the inode table
690 * block has been written back to disk. (Yes, these values are
691 * somewhat arbitrary...)
693 #define RECENTCY_MIN 5
694 #define RECENTCY_DIRTY 30
696 static int recently_deleted(struct super_block
*sb
, ext4_group_t group
, int ino
)
698 struct ext4_group_desc
*gdp
;
699 struct ext4_inode
*raw_inode
;
700 struct buffer_head
*bh
;
701 unsigned long dtime
, now
;
702 int inodes_per_block
= EXT4_SB(sb
)->s_inodes_per_block
;
703 int offset
, ret
= 0, recentcy
= RECENTCY_MIN
;
705 gdp
= ext4_get_group_desc(sb
, group
, NULL
);
709 bh
= sb_getblk(sb
, ext4_inode_table(sb
, gdp
) +
710 (ino
/ inodes_per_block
));
711 if (unlikely(!bh
) || !buffer_uptodate(bh
))
713 * If the block is not in the buffer cache, then it
714 * must have been written out.
718 offset
= (ino
% inodes_per_block
) * EXT4_INODE_SIZE(sb
);
719 raw_inode
= (struct ext4_inode
*) (bh
->b_data
+ offset
);
720 dtime
= le32_to_cpu(raw_inode
->i_dtime
);
722 if (buffer_dirty(bh
))
723 recentcy
+= RECENTCY_DIRTY
;
725 if (dtime
&& (dtime
< now
) && (now
< dtime
+ recentcy
))
733 * There are two policies for allocating an inode. If the new inode is
734 * a directory, then a forward search is made for a block group with both
735 * free space and a low directory-to-inode ratio; if that fails, then of
736 * the groups with above-average free space, that group with the fewest
737 * directories already is chosen.
739 * For other inodes, search forward from the parent directory's block
740 * group to find a free inode.
742 struct inode
*__ext4_new_inode(handle_t
*handle
, struct inode
*dir
,
743 umode_t mode
, const struct qstr
*qstr
,
744 __u32 goal
, uid_t
*owner
, int handle_type
,
745 unsigned int line_no
, int nblocks
)
747 struct super_block
*sb
;
748 struct buffer_head
*inode_bitmap_bh
= NULL
;
749 struct buffer_head
*group_desc_bh
;
750 ext4_group_t ngroups
, group
= 0;
751 unsigned long ino
= 0;
753 struct ext4_group_desc
*gdp
= NULL
;
754 struct ext4_inode_info
*ei
;
755 struct ext4_sb_info
*sbi
;
759 ext4_group_t flex_group
;
760 struct ext4_group_info
*grp
;
763 /* Cannot create files in a deleted directory */
764 if (!dir
|| !dir
->i_nlink
)
765 return ERR_PTR(-EPERM
);
767 if ((ext4_encrypted_inode(dir
) ||
768 DUMMY_ENCRYPTION_ENABLED(EXT4_SB(dir
->i_sb
))) &&
769 (S_ISREG(mode
) || S_ISDIR(mode
) || S_ISLNK(mode
))) {
770 err
= ext4_get_encryption_info(dir
);
773 if (ext4_encryption_info(dir
) == NULL
)
774 return ERR_PTR(-EPERM
);
776 nblocks
+= EXT4_DATA_TRANS_BLOCKS(dir
->i_sb
);
781 ngroups
= ext4_get_groups_count(sb
);
782 trace_ext4_request_inode(dir
, mode
);
783 inode
= new_inode(sb
);
785 return ERR_PTR(-ENOMEM
);
790 * Initialize owners and quota early so that we don't have to account
791 * for quota initialization worst case in standard inode creating
795 inode
->i_mode
= mode
;
796 i_uid_write(inode
, owner
[0]);
797 i_gid_write(inode
, owner
[1]);
798 } else if (test_opt(sb
, GRPID
)) {
799 inode
->i_mode
= mode
;
800 inode
->i_uid
= current_fsuid();
801 inode
->i_gid
= dir
->i_gid
;
803 inode_init_owner(inode
, dir
, mode
);
805 if (EXT4_HAS_RO_COMPAT_FEATURE(sb
, EXT4_FEATURE_RO_COMPAT_PROJECT
) &&
806 ext4_test_inode_flag(dir
, EXT4_INODE_PROJINHERIT
))
807 ei
->i_projid
= EXT4_I(dir
)->i_projid
;
809 ei
->i_projid
= make_kprojid(&init_user_ns
, EXT4_DEF_PROJID
);
811 err
= dquot_initialize(inode
);
816 goal
= sbi
->s_inode_goal
;
818 if (goal
&& goal
<= le32_to_cpu(sbi
->s_es
->s_inodes_count
)) {
819 group
= (goal
- 1) / EXT4_INODES_PER_GROUP(sb
);
820 ino
= (goal
- 1) % EXT4_INODES_PER_GROUP(sb
);
826 ret2
= find_group_orlov(sb
, dir
, &group
, mode
, qstr
);
828 ret2
= find_group_other(sb
, dir
, &group
, mode
);
831 EXT4_I(dir
)->i_last_alloc_group
= group
;
837 * Normally we will only go through one pass of this loop,
838 * unless we get unlucky and it turns out the group we selected
839 * had its last inode grabbed by someone else.
841 for (i
= 0; i
< ngroups
; i
++, ino
= 0) {
844 gdp
= ext4_get_group_desc(sb
, group
, &group_desc_bh
);
849 * Check free inodes count before loading bitmap.
851 if (ext4_free_inodes_count(sb
, gdp
) == 0) {
852 if (++group
== ngroups
)
857 grp
= ext4_get_group_info(sb
, group
);
858 /* Skip groups with already-known suspicious inode tables */
859 if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp
)) {
860 if (++group
== ngroups
)
865 brelse(inode_bitmap_bh
);
866 inode_bitmap_bh
= ext4_read_inode_bitmap(sb
, group
);
867 /* Skip groups with suspicious inode tables */
868 if (EXT4_MB_GRP_IBITMAP_CORRUPT(grp
) ||
869 IS_ERR(inode_bitmap_bh
)) {
870 inode_bitmap_bh
= NULL
;
871 if (++group
== ngroups
)
876 repeat_in_this_group
:
877 ino
= ext4_find_next_zero_bit((unsigned long *)
878 inode_bitmap_bh
->b_data
,
879 EXT4_INODES_PER_GROUP(sb
), ino
);
880 if (ino
>= EXT4_INODES_PER_GROUP(sb
))
882 if (group
== 0 && (ino
+1) < EXT4_FIRST_INO(sb
)) {
883 ext4_error(sb
, "reserved inode found cleared - "
884 "inode=%lu", ino
+ 1);
887 if ((EXT4_SB(sb
)->s_journal
== NULL
) &&
888 recently_deleted(sb
, group
, ino
)) {
893 BUG_ON(nblocks
<= 0);
894 handle
= __ext4_journal_start_sb(dir
->i_sb
, line_no
,
895 handle_type
, nblocks
,
897 if (IS_ERR(handle
)) {
898 err
= PTR_ERR(handle
);
899 ext4_std_error(sb
, err
);
903 BUFFER_TRACE(inode_bitmap_bh
, "get_write_access");
904 err
= ext4_journal_get_write_access(handle
, inode_bitmap_bh
);
906 ext4_std_error(sb
, err
);
909 ext4_lock_group(sb
, group
);
910 ret2
= ext4_test_and_set_bit(ino
, inode_bitmap_bh
->b_data
);
911 ext4_unlock_group(sb
, group
);
912 ino
++; /* the inode bitmap is zero-based */
914 goto got
; /* we grabbed the inode! */
916 if (ino
< EXT4_INODES_PER_GROUP(sb
))
917 goto repeat_in_this_group
;
919 if (++group
== ngroups
)
926 BUFFER_TRACE(inode_bitmap_bh
, "call ext4_handle_dirty_metadata");
927 err
= ext4_handle_dirty_metadata(handle
, NULL
, inode_bitmap_bh
);
929 ext4_std_error(sb
, err
);
933 BUFFER_TRACE(group_desc_bh
, "get_write_access");
934 err
= ext4_journal_get_write_access(handle
, group_desc_bh
);
936 ext4_std_error(sb
, err
);
940 /* We may have to initialize the block bitmap if it isn't already */
941 if (ext4_has_group_desc_csum(sb
) &&
942 gdp
->bg_flags
& cpu_to_le16(EXT4_BG_BLOCK_UNINIT
)) {
943 struct buffer_head
*block_bitmap_bh
;
945 block_bitmap_bh
= ext4_read_block_bitmap(sb
, group
);
946 if (IS_ERR(block_bitmap_bh
)) {
947 err
= PTR_ERR(block_bitmap_bh
);
950 BUFFER_TRACE(block_bitmap_bh
, "get block bitmap access");
951 err
= ext4_journal_get_write_access(handle
, block_bitmap_bh
);
953 brelse(block_bitmap_bh
);
954 ext4_std_error(sb
, err
);
958 BUFFER_TRACE(block_bitmap_bh
, "dirty block bitmap");
959 err
= ext4_handle_dirty_metadata(handle
, NULL
, block_bitmap_bh
);
961 /* recheck and clear flag under lock if we still need to */
962 ext4_lock_group(sb
, group
);
963 if (gdp
->bg_flags
& cpu_to_le16(EXT4_BG_BLOCK_UNINIT
)) {
964 gdp
->bg_flags
&= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT
);
965 ext4_free_group_clusters_set(sb
, gdp
,
966 ext4_free_clusters_after_init(sb
, group
, gdp
));
967 ext4_block_bitmap_csum_set(sb
, group
, gdp
,
969 ext4_group_desc_csum_set(sb
, group
, gdp
);
971 ext4_unlock_group(sb
, group
);
972 brelse(block_bitmap_bh
);
975 ext4_std_error(sb
, err
);
980 /* Update the relevant bg descriptor fields */
981 if (ext4_has_group_desc_csum(sb
)) {
983 struct ext4_group_info
*grp
= ext4_get_group_info(sb
, group
);
985 down_read(&grp
->alloc_sem
); /* protect vs itable lazyinit */
986 ext4_lock_group(sb
, group
); /* while we modify the bg desc */
987 free
= EXT4_INODES_PER_GROUP(sb
) -
988 ext4_itable_unused_count(sb
, gdp
);
989 if (gdp
->bg_flags
& cpu_to_le16(EXT4_BG_INODE_UNINIT
)) {
990 gdp
->bg_flags
&= cpu_to_le16(~EXT4_BG_INODE_UNINIT
);
994 * Check the relative inode number against the last used
995 * relative inode number in this group. if it is greater
996 * we need to update the bg_itable_unused count
999 ext4_itable_unused_set(sb
, gdp
,
1000 (EXT4_INODES_PER_GROUP(sb
) - ino
));
1001 up_read(&grp
->alloc_sem
);
1003 ext4_lock_group(sb
, group
);
1006 ext4_free_inodes_set(sb
, gdp
, ext4_free_inodes_count(sb
, gdp
) - 1);
1007 if (S_ISDIR(mode
)) {
1008 ext4_used_dirs_set(sb
, gdp
, ext4_used_dirs_count(sb
, gdp
) + 1);
1009 if (sbi
->s_log_groups_per_flex
) {
1010 ext4_group_t f
= ext4_flex_group(sbi
, group
);
1012 atomic_inc(&sbi
->s_flex_groups
[f
].used_dirs
);
1015 if (ext4_has_group_desc_csum(sb
)) {
1016 ext4_inode_bitmap_csum_set(sb
, group
, gdp
, inode_bitmap_bh
,
1017 EXT4_INODES_PER_GROUP(sb
) / 8);
1018 ext4_group_desc_csum_set(sb
, group
, gdp
);
1020 ext4_unlock_group(sb
, group
);
1022 BUFFER_TRACE(group_desc_bh
, "call ext4_handle_dirty_metadata");
1023 err
= ext4_handle_dirty_metadata(handle
, NULL
, group_desc_bh
);
1025 ext4_std_error(sb
, err
);
1029 percpu_counter_dec(&sbi
->s_freeinodes_counter
);
1031 percpu_counter_inc(&sbi
->s_dirs_counter
);
1033 if (sbi
->s_log_groups_per_flex
) {
1034 flex_group
= ext4_flex_group(sbi
, group
);
1035 atomic_dec(&sbi
->s_flex_groups
[flex_group
].free_inodes
);
1038 inode
->i_ino
= ino
+ group
* EXT4_INODES_PER_GROUP(sb
);
1039 /* This is the optimal IO size (for stat), not the fs block size */
1040 inode
->i_blocks
= 0;
1041 inode
->i_mtime
= inode
->i_atime
= inode
->i_ctime
= ei
->i_crtime
=
1042 ext4_current_time(inode
);
1044 memset(ei
->i_data
, 0, sizeof(ei
->i_data
));
1045 ei
->i_dir_start_lookup
= 0;
1048 /* Don't inherit extent flag from directory, amongst others. */
1050 ext4_mask_flags(mode
, EXT4_I(dir
)->i_flags
& EXT4_FL_INHERITED
);
1053 ei
->i_block_group
= group
;
1054 ei
->i_last_alloc_group
= ~0;
1056 ext4_set_inode_flags(inode
);
1057 if (IS_DIRSYNC(inode
))
1058 ext4_handle_sync(handle
);
1059 if (insert_inode_locked(inode
) < 0) {
1061 * Likely a bitmap corruption causing inode to be allocated
1065 ext4_error(sb
, "failed to insert inode %lu: doubly allocated?",
1069 spin_lock(&sbi
->s_next_gen_lock
);
1070 inode
->i_generation
= sbi
->s_next_generation
++;
1071 spin_unlock(&sbi
->s_next_gen_lock
);
1073 /* Precompute checksum seed for inode metadata */
1074 if (ext4_has_metadata_csum(sb
)) {
1076 __le32 inum
= cpu_to_le32(inode
->i_ino
);
1077 __le32 gen
= cpu_to_le32(inode
->i_generation
);
1078 csum
= ext4_chksum(sbi
, sbi
->s_csum_seed
, (__u8
*)&inum
,
1080 ei
->i_csum_seed
= ext4_chksum(sbi
, csum
, (__u8
*)&gen
,
1084 ext4_clear_state_flags(ei
); /* Only relevant on 32-bit archs */
1085 ext4_set_inode_state(inode
, EXT4_STATE_NEW
);
1087 ei
->i_extra_isize
= EXT4_SB(sb
)->s_want_extra_isize
;
1088 ei
->i_inline_off
= 0;
1089 if (ext4_has_feature_inline_data(sb
))
1090 ext4_set_inode_state(inode
, EXT4_STATE_MAY_INLINE_DATA
);
1092 err
= dquot_alloc_inode(inode
);
1096 err
= ext4_init_acl(handle
, inode
, dir
);
1098 goto fail_free_drop
;
1100 err
= ext4_init_security(handle
, inode
, dir
, qstr
);
1102 goto fail_free_drop
;
1104 if (ext4_has_feature_extents(sb
)) {
1105 /* set extent flag only for directory, file and normal symlink*/
1106 if (S_ISDIR(mode
) || S_ISREG(mode
) || S_ISLNK(mode
)) {
1107 ext4_set_inode_flag(inode
, EXT4_INODE_EXTENTS
);
1108 ext4_ext_tree_init(handle
, inode
);
1112 if (ext4_handle_valid(handle
)) {
1113 ei
->i_sync_tid
= handle
->h_transaction
->t_tid
;
1114 ei
->i_datasync_tid
= handle
->h_transaction
->t_tid
;
1118 err
= ext4_inherit_context(dir
, inode
);
1120 goto fail_free_drop
;
1123 err
= ext4_mark_inode_dirty(handle
, inode
);
1125 ext4_std_error(sb
, err
);
1126 goto fail_free_drop
;
1129 ext4_debug("allocating inode %lu\n", inode
->i_ino
);
1130 trace_ext4_allocate_inode(inode
, dir
, mode
);
1131 brelse(inode_bitmap_bh
);
1135 dquot_free_inode(inode
);
1138 unlock_new_inode(inode
);
1141 inode
->i_flags
|= S_NOQUOTA
;
1143 brelse(inode_bitmap_bh
);
1144 return ERR_PTR(err
);
1147 /* Verify that we are loading a valid orphan from disk */
1148 struct inode
*ext4_orphan_get(struct super_block
*sb
, unsigned long ino
)
1150 unsigned long max_ino
= le32_to_cpu(EXT4_SB(sb
)->s_es
->s_inodes_count
);
1151 ext4_group_t block_group
;
1153 struct buffer_head
*bitmap_bh
;
1154 struct inode
*inode
= NULL
;
1157 /* Error cases - e2fsck has already cleaned up for us */
1158 if (ino
> max_ino
) {
1159 ext4_warning(sb
, "bad orphan ino %lu! e2fsck was run?", ino
);
1160 err
= -EFSCORRUPTED
;
1164 block_group
= (ino
- 1) / EXT4_INODES_PER_GROUP(sb
);
1165 bit
= (ino
- 1) % EXT4_INODES_PER_GROUP(sb
);
1166 bitmap_bh
= ext4_read_inode_bitmap(sb
, block_group
);
1167 if (IS_ERR(bitmap_bh
)) {
1168 err
= PTR_ERR(bitmap_bh
);
1169 ext4_warning(sb
, "inode bitmap error %ld for orphan %lu",
1174 /* Having the inode bit set should be a 100% indicator that this
1175 * is a valid orphan (no e2fsck run on fs). Orphans also include
1176 * inodes that were being truncated, so we can't check i_nlink==0.
1178 if (!ext4_test_bit(bit
, bitmap_bh
->b_data
))
1181 inode
= ext4_iget(sb
, ino
);
1186 * If the orphans has i_nlinks > 0 then it should be able to be
1187 * truncated, otherwise it won't be removed from the orphan list
1188 * during processing and an infinite loop will result.
1190 if (inode
->i_nlink
&& !ext4_can_truncate(inode
))
1193 if (NEXT_ORPHAN(inode
) > max_ino
)
1199 err
= PTR_ERR(inode
);
1202 ext4_warning(sb
, "bad orphan inode %lu! e2fsck was run?", ino
);
1203 printk(KERN_WARNING
"ext4_test_bit(bit=%d, block=%llu) = %d\n",
1204 bit
, (unsigned long long)bitmap_bh
->b_blocknr
,
1205 ext4_test_bit(bit
, bitmap_bh
->b_data
));
1206 printk(KERN_WARNING
"inode=%p\n", inode
);
1208 printk(KERN_WARNING
"is_bad_inode(inode)=%d\n",
1209 is_bad_inode(inode
));
1210 printk(KERN_WARNING
"NEXT_ORPHAN(inode)=%u\n",
1211 NEXT_ORPHAN(inode
));
1212 printk(KERN_WARNING
"max_ino=%lu\n", max_ino
);
1213 printk(KERN_WARNING
"i_nlink=%u\n", inode
->i_nlink
);
1214 /* Avoid freeing blocks if we got a bad deleted inode */
1215 if (inode
->i_nlink
== 0)
1216 inode
->i_blocks
= 0;
1221 return ERR_PTR(err
);
1224 unsigned long ext4_count_free_inodes(struct super_block
*sb
)
1226 unsigned long desc_count
;
1227 struct ext4_group_desc
*gdp
;
1228 ext4_group_t i
, ngroups
= ext4_get_groups_count(sb
);
1230 struct ext4_super_block
*es
;
1231 unsigned long bitmap_count
, x
;
1232 struct buffer_head
*bitmap_bh
= NULL
;
1234 es
= EXT4_SB(sb
)->s_es
;
1238 for (i
= 0; i
< ngroups
; i
++) {
1239 gdp
= ext4_get_group_desc(sb
, i
, NULL
);
1242 desc_count
+= ext4_free_inodes_count(sb
, gdp
);
1244 bitmap_bh
= ext4_read_inode_bitmap(sb
, i
);
1245 if (IS_ERR(bitmap_bh
)) {
1250 x
= ext4_count_free(bitmap_bh
->b_data
,
1251 EXT4_INODES_PER_GROUP(sb
) / 8);
1252 printk(KERN_DEBUG
"group %lu: stored = %d, counted = %lu\n",
1253 (unsigned long) i
, ext4_free_inodes_count(sb
, gdp
), x
);
1257 printk(KERN_DEBUG
"ext4_count_free_inodes: "
1258 "stored = %u, computed = %lu, %lu\n",
1259 le32_to_cpu(es
->s_free_inodes_count
), desc_count
, bitmap_count
);
1263 for (i
= 0; i
< ngroups
; i
++) {
1264 gdp
= ext4_get_group_desc(sb
, i
, NULL
);
1267 desc_count
+= ext4_free_inodes_count(sb
, gdp
);
1274 /* Called at mount-time, super-block is locked */
1275 unsigned long ext4_count_dirs(struct super_block
* sb
)
1277 unsigned long count
= 0;
1278 ext4_group_t i
, ngroups
= ext4_get_groups_count(sb
);
1280 for (i
= 0; i
< ngroups
; i
++) {
1281 struct ext4_group_desc
*gdp
= ext4_get_group_desc(sb
, i
, NULL
);
1284 count
+= ext4_used_dirs_count(sb
, gdp
);
1290 * Zeroes not yet zeroed inode table - just write zeroes through the whole
1291 * inode table. Must be called without any spinlock held. The only place
1292 * where it is called from on active part of filesystem is ext4lazyinit
1293 * thread, so we do not need any special locks, however we have to prevent
1294 * inode allocation from the current group, so we take alloc_sem lock, to
1295 * block ext4_new_inode() until we are finished.
1297 int ext4_init_inode_table(struct super_block
*sb
, ext4_group_t group
,
1300 struct ext4_group_info
*grp
= ext4_get_group_info(sb
, group
);
1301 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1302 struct ext4_group_desc
*gdp
= NULL
;
1303 struct buffer_head
*group_desc_bh
;
1306 int num
, ret
= 0, used_blks
= 0;
1308 /* This should not happen, but just to be sure check this */
1309 if (sb
->s_flags
& MS_RDONLY
) {
1314 gdp
= ext4_get_group_desc(sb
, group
, &group_desc_bh
);
1319 * We do not need to lock this, because we are the only one
1320 * handling this flag.
1322 if (gdp
->bg_flags
& cpu_to_le16(EXT4_BG_INODE_ZEROED
))
1325 handle
= ext4_journal_start_sb(sb
, EXT4_HT_MISC
, 1);
1326 if (IS_ERR(handle
)) {
1327 ret
= PTR_ERR(handle
);
1331 down_write(&grp
->alloc_sem
);
1333 * If inode bitmap was already initialized there may be some
1334 * used inodes so we need to skip blocks with used inodes in
1337 if (!(gdp
->bg_flags
& cpu_to_le16(EXT4_BG_INODE_UNINIT
)))
1338 used_blks
= DIV_ROUND_UP((EXT4_INODES_PER_GROUP(sb
) -
1339 ext4_itable_unused_count(sb
, gdp
)),
1340 sbi
->s_inodes_per_block
);
1342 if ((used_blks
< 0) || (used_blks
> sbi
->s_itb_per_group
)) {
1343 ext4_error(sb
, "Something is wrong with group %u: "
1344 "used itable blocks: %d; "
1345 "itable unused count: %u",
1347 ext4_itable_unused_count(sb
, gdp
));
1352 blk
= ext4_inode_table(sb
, gdp
) + used_blks
;
1353 num
= sbi
->s_itb_per_group
- used_blks
;
1355 BUFFER_TRACE(group_desc_bh
, "get_write_access");
1356 ret
= ext4_journal_get_write_access(handle
,
1362 * Skip zeroout if the inode table is full. But we set the ZEROED
1363 * flag anyway, because obviously, when it is full it does not need
1366 if (unlikely(num
== 0))
1369 ext4_debug("going to zero out inode table in group %d\n",
1371 ret
= sb_issue_zeroout(sb
, blk
, num
, GFP_NOFS
);
1375 blkdev_issue_flush(sb
->s_bdev
, GFP_NOFS
, NULL
);
1378 ext4_lock_group(sb
, group
);
1379 gdp
->bg_flags
|= cpu_to_le16(EXT4_BG_INODE_ZEROED
);
1380 ext4_group_desc_csum_set(sb
, group
, gdp
);
1381 ext4_unlock_group(sb
, group
);
1383 BUFFER_TRACE(group_desc_bh
,
1384 "call ext4_handle_dirty_metadata");
1385 ret
= ext4_handle_dirty_metadata(handle
, NULL
,
1389 up_write(&grp
->alloc_sem
);
1390 ext4_journal_stop(handle
);