1 // SPDX-License-Identifier: GPL-2.0
3 * linux/fs/ext4/resize.c
5 * Support for resizing an ext4 filesystem while it is mounted.
7 * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com>
9 * This could probably be made into a module, because it is not often in use.
15 #include <linux/errno.h>
16 #include <linux/slab.h>
18 #include "ext4_jbd2.h"
20 int ext4_resize_begin(struct super_block
*sb
)
22 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
25 if (!capable(CAP_SYS_RESOURCE
))
29 * If we are not using the primary superblock/GDT copy don't resize,
30 * because the user tools have no way of handling this. Probably a
31 * bad time to do it anyways.
33 if (EXT4_B2C(sbi
, sbi
->s_sbh
->b_blocknr
) !=
34 le32_to_cpu(EXT4_SB(sb
)->s_es
->s_first_data_block
)) {
35 ext4_warning(sb
, "won't resize using backup superblock at %llu",
36 (unsigned long long)EXT4_SB(sb
)->s_sbh
->b_blocknr
);
41 * We are not allowed to do online-resizing on a filesystem mounted
42 * with error, because it can destroy the filesystem easily.
44 if (EXT4_SB(sb
)->s_mount_state
& EXT4_ERROR_FS
) {
45 ext4_warning(sb
, "There are errors in the filesystem, "
46 "so online resizing is not allowed");
50 if (test_and_set_bit_lock(EXT4_FLAGS_RESIZING
,
51 &EXT4_SB(sb
)->s_ext4_flags
))
57 void ext4_resize_end(struct super_block
*sb
)
59 clear_bit_unlock(EXT4_FLAGS_RESIZING
, &EXT4_SB(sb
)->s_ext4_flags
);
60 smp_mb__after_atomic();
63 static ext4_group_t
ext4_meta_bg_first_group(struct super_block
*sb
,
65 return (group
>> EXT4_DESC_PER_BLOCK_BITS(sb
)) <<
66 EXT4_DESC_PER_BLOCK_BITS(sb
);
69 static ext4_fsblk_t
ext4_meta_bg_first_block_no(struct super_block
*sb
,
71 group
= ext4_meta_bg_first_group(sb
, group
);
72 return ext4_group_first_block_no(sb
, group
);
75 static ext4_grpblk_t
ext4_group_overhead_blocks(struct super_block
*sb
,
77 ext4_grpblk_t overhead
;
78 overhead
= ext4_bg_num_gdb(sb
, group
);
79 if (ext4_bg_has_super(sb
, group
))
81 le16_to_cpu(EXT4_SB(sb
)->s_es
->s_reserved_gdt_blocks
);
85 #define outside(b, first, last) ((b) < (first) || (b) >= (last))
86 #define inside(b, first, last) ((b) >= (first) && (b) < (last))
88 static int verify_group_input(struct super_block
*sb
,
89 struct ext4_new_group_data
*input
)
91 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
92 struct ext4_super_block
*es
= sbi
->s_es
;
93 ext4_fsblk_t start
= ext4_blocks_count(es
);
94 ext4_fsblk_t end
= start
+ input
->blocks_count
;
95 ext4_group_t group
= input
->group
;
96 ext4_fsblk_t itend
= input
->inode_table
+ sbi
->s_itb_per_group
;
99 struct buffer_head
*bh
= NULL
;
100 ext4_grpblk_t free_blocks_count
, offset
;
103 if (group
!= sbi
->s_groups_count
) {
104 ext4_warning(sb
, "Cannot add at group %u (only %u groups)",
105 input
->group
, sbi
->s_groups_count
);
109 overhead
= ext4_group_overhead_blocks(sb
, group
);
110 metaend
= start
+ overhead
;
111 input
->free_clusters_count
= free_blocks_count
=
112 input
->blocks_count
- 2 - overhead
- sbi
->s_itb_per_group
;
114 if (test_opt(sb
, DEBUG
))
115 printk(KERN_DEBUG
"EXT4-fs: adding %s group %u: %u blocks "
116 "(%d free, %u reserved)\n",
117 ext4_bg_has_super(sb
, input
->group
) ? "normal" :
118 "no-super", input
->group
, input
->blocks_count
,
119 free_blocks_count
, input
->reserved_blocks
);
121 ext4_get_group_no_and_offset(sb
, start
, NULL
, &offset
);
123 ext4_warning(sb
, "Last group not full");
124 else if (input
->reserved_blocks
> input
->blocks_count
/ 5)
125 ext4_warning(sb
, "Reserved blocks too high (%u)",
126 input
->reserved_blocks
);
127 else if (free_blocks_count
< 0)
128 ext4_warning(sb
, "Bad blocks count %u",
129 input
->blocks_count
);
130 else if (IS_ERR(bh
= ext4_sb_bread(sb
, end
- 1, 0))) {
133 ext4_warning(sb
, "Cannot read last block (%llu)",
135 } else if (outside(input
->block_bitmap
, start
, end
))
136 ext4_warning(sb
, "Block bitmap not in group (block %llu)",
137 (unsigned long long)input
->block_bitmap
);
138 else if (outside(input
->inode_bitmap
, start
, end
))
139 ext4_warning(sb
, "Inode bitmap not in group (block %llu)",
140 (unsigned long long)input
->inode_bitmap
);
141 else if (outside(input
->inode_table
, start
, end
) ||
142 outside(itend
- 1, start
, end
))
143 ext4_warning(sb
, "Inode table not in group (blocks %llu-%llu)",
144 (unsigned long long)input
->inode_table
, itend
- 1);
145 else if (input
->inode_bitmap
== input
->block_bitmap
)
146 ext4_warning(sb
, "Block bitmap same as inode bitmap (%llu)",
147 (unsigned long long)input
->block_bitmap
);
148 else if (inside(input
->block_bitmap
, input
->inode_table
, itend
))
149 ext4_warning(sb
, "Block bitmap (%llu) in inode table "
151 (unsigned long long)input
->block_bitmap
,
152 (unsigned long long)input
->inode_table
, itend
- 1);
153 else if (inside(input
->inode_bitmap
, input
->inode_table
, itend
))
154 ext4_warning(sb
, "Inode bitmap (%llu) in inode table "
156 (unsigned long long)input
->inode_bitmap
,
157 (unsigned long long)input
->inode_table
, itend
- 1);
158 else if (inside(input
->block_bitmap
, start
, metaend
))
159 ext4_warning(sb
, "Block bitmap (%llu) in GDT table (%llu-%llu)",
160 (unsigned long long)input
->block_bitmap
,
162 else if (inside(input
->inode_bitmap
, start
, metaend
))
163 ext4_warning(sb
, "Inode bitmap (%llu) in GDT table (%llu-%llu)",
164 (unsigned long long)input
->inode_bitmap
,
166 else if (inside(input
->inode_table
, start
, metaend
) ||
167 inside(itend
- 1, start
, metaend
))
168 ext4_warning(sb
, "Inode table (%llu-%llu) overlaps GDT table "
170 (unsigned long long)input
->inode_table
,
171 itend
- 1, start
, metaend
- 1);
180 * ext4_new_flex_group_data is used by 64bit-resize interface to add a flex
183 struct ext4_new_flex_group_data
{
184 struct ext4_new_group_data
*groups
; /* new_group_data for groups
186 __u16
*bg_flags
; /* block group flags of groups
188 ext4_group_t count
; /* number of groups in @groups
193 * alloc_flex_gd() allocates a ext4_new_flex_group_data with size of
196 * Returns NULL on failure otherwise address of the allocated structure.
198 static struct ext4_new_flex_group_data
*alloc_flex_gd(unsigned long flexbg_size
)
200 struct ext4_new_flex_group_data
*flex_gd
;
202 flex_gd
= kmalloc(sizeof(*flex_gd
), GFP_NOFS
);
206 if (flexbg_size
>= UINT_MAX
/ sizeof(struct ext4_new_group_data
))
208 flex_gd
->count
= flexbg_size
;
210 flex_gd
->groups
= kmalloc_array(flexbg_size
,
211 sizeof(struct ext4_new_group_data
),
213 if (flex_gd
->groups
== NULL
)
216 flex_gd
->bg_flags
= kmalloc_array(flexbg_size
, sizeof(__u16
),
218 if (flex_gd
->bg_flags
== NULL
)
224 kfree(flex_gd
->groups
);
231 static void free_flex_gd(struct ext4_new_flex_group_data
*flex_gd
)
233 kfree(flex_gd
->bg_flags
);
234 kfree(flex_gd
->groups
);
239 * ext4_alloc_group_tables() allocates block bitmaps, inode bitmaps
240 * and inode tables for a flex group.
242 * This function is used by 64bit-resize. Note that this function allocates
243 * group tables from the 1st group of groups contained by @flexgd, which may
244 * be a partial of a flex group.
246 * @sb: super block of fs to which the groups belongs
248 * Returns 0 on a successful allocation of the metadata blocks in the
251 static int ext4_alloc_group_tables(struct super_block
*sb
,
252 struct ext4_new_flex_group_data
*flex_gd
,
255 struct ext4_new_group_data
*group_data
= flex_gd
->groups
;
256 ext4_fsblk_t start_blk
;
257 ext4_fsblk_t last_blk
;
258 ext4_group_t src_group
;
259 ext4_group_t bb_index
= 0;
260 ext4_group_t ib_index
= 0;
261 ext4_group_t it_index
= 0;
263 ext4_group_t last_group
;
265 __u16 uninit_mask
= (flexbg_size
> 1) ? ~EXT4_BG_BLOCK_UNINIT
: ~0;
268 BUG_ON(flex_gd
->count
== 0 || group_data
== NULL
);
270 src_group
= group_data
[0].group
;
271 last_group
= src_group
+ flex_gd
->count
- 1;
273 BUG_ON((flexbg_size
> 1) && ((src_group
& ~(flexbg_size
- 1)) !=
274 (last_group
& ~(flexbg_size
- 1))));
276 group
= group_data
[0].group
;
277 if (src_group
>= group_data
[0].group
+ flex_gd
->count
)
279 start_blk
= ext4_group_first_block_no(sb
, src_group
);
280 last_blk
= start_blk
+ group_data
[src_group
- group
].blocks_count
;
282 overhead
= ext4_group_overhead_blocks(sb
, src_group
);
284 start_blk
+= overhead
;
286 /* We collect contiguous blocks as much as possible. */
288 for (; src_group
<= last_group
; src_group
++) {
289 overhead
= ext4_group_overhead_blocks(sb
, src_group
);
291 last_blk
+= group_data
[src_group
- group
].blocks_count
;
296 /* Allocate block bitmaps */
297 for (; bb_index
< flex_gd
->count
; bb_index
++) {
298 if (start_blk
>= last_blk
)
300 group_data
[bb_index
].block_bitmap
= start_blk
++;
301 group
= ext4_get_group_number(sb
, start_blk
- 1);
302 group
-= group_data
[0].group
;
303 group_data
[group
].mdata_blocks
++;
304 flex_gd
->bg_flags
[group
] &= uninit_mask
;
307 /* Allocate inode bitmaps */
308 for (; ib_index
< flex_gd
->count
; ib_index
++) {
309 if (start_blk
>= last_blk
)
311 group_data
[ib_index
].inode_bitmap
= start_blk
++;
312 group
= ext4_get_group_number(sb
, start_blk
- 1);
313 group
-= group_data
[0].group
;
314 group_data
[group
].mdata_blocks
++;
315 flex_gd
->bg_flags
[group
] &= uninit_mask
;
318 /* Allocate inode tables */
319 for (; it_index
< flex_gd
->count
; it_index
++) {
320 unsigned int itb
= EXT4_SB(sb
)->s_itb_per_group
;
321 ext4_fsblk_t next_group_start
;
323 if (start_blk
+ itb
> last_blk
)
325 group_data
[it_index
].inode_table
= start_blk
;
326 group
= ext4_get_group_number(sb
, start_blk
);
327 next_group_start
= ext4_group_first_block_no(sb
, group
+ 1);
328 group
-= group_data
[0].group
;
330 if (start_blk
+ itb
> next_group_start
) {
331 flex_gd
->bg_flags
[group
+ 1] &= uninit_mask
;
332 overhead
= start_blk
+ itb
- next_group_start
;
333 group_data
[group
+ 1].mdata_blocks
+= overhead
;
337 group_data
[group
].mdata_blocks
+= itb
;
338 flex_gd
->bg_flags
[group
] &= uninit_mask
;
339 start_blk
+= EXT4_SB(sb
)->s_itb_per_group
;
342 /* Update free clusters count to exclude metadata blocks */
343 for (i
= 0; i
< flex_gd
->count
; i
++) {
344 group_data
[i
].free_clusters_count
-=
345 EXT4_NUM_B2C(EXT4_SB(sb
),
346 group_data
[i
].mdata_blocks
);
349 if (test_opt(sb
, DEBUG
)) {
351 group
= group_data
[0].group
;
353 printk(KERN_DEBUG
"EXT4-fs: adding a flex group with "
354 "%d groups, flexbg size is %d:\n", flex_gd
->count
,
357 for (i
= 0; i
< flex_gd
->count
; i
++) {
359 "adding %s group %u: %u blocks (%d free, %d mdata blocks)\n",
360 ext4_bg_has_super(sb
, group
+ i
) ? "normal" :
361 "no-super", group
+ i
,
362 group_data
[i
].blocks_count
,
363 group_data
[i
].free_clusters_count
,
364 group_data
[i
].mdata_blocks
);
370 static struct buffer_head
*bclean(handle_t
*handle
, struct super_block
*sb
,
373 struct buffer_head
*bh
;
376 bh
= sb_getblk(sb
, blk
);
378 return ERR_PTR(-ENOMEM
);
379 BUFFER_TRACE(bh
, "get_write_access");
380 if ((err
= ext4_journal_get_write_access(handle
, bh
))) {
384 memset(bh
->b_data
, 0, sb
->s_blocksize
);
385 set_buffer_uptodate(bh
);
392 * If we have fewer than thresh credits, extend by EXT4_MAX_TRANS_DATA.
393 * If that fails, restart the transaction & regain write access for the
394 * buffer head which is used for block_bitmap modifications.
396 static int extend_or_restart_transaction(handle_t
*handle
, int thresh
)
400 if (ext4_handle_has_enough_credits(handle
, thresh
))
403 err
= ext4_journal_extend(handle
, EXT4_MAX_TRANS_DATA
);
407 err
= ext4_journal_restart(handle
, EXT4_MAX_TRANS_DATA
);
416 * set_flexbg_block_bitmap() mark clusters [@first_cluster, @last_cluster] used.
418 * Helper function for ext4_setup_new_group_blocks() which set .
421 * @handle: journal handle
422 * @flex_gd: flex group data
424 static int set_flexbg_block_bitmap(struct super_block
*sb
, handle_t
*handle
,
425 struct ext4_new_flex_group_data
*flex_gd
,
426 ext4_fsblk_t first_cluster
, ext4_fsblk_t last_cluster
)
428 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
429 ext4_group_t count
= last_cluster
- first_cluster
+ 1;
432 ext4_debug("mark clusters [%llu-%llu] used\n", first_cluster
,
434 for (count2
= count
; count
> 0;
435 count
-= count2
, first_cluster
+= count2
) {
437 struct buffer_head
*bh
;
441 group
= ext4_get_group_number(sb
, EXT4_C2B(sbi
, first_cluster
));
442 start
= EXT4_B2C(sbi
, ext4_group_first_block_no(sb
, group
));
443 group
-= flex_gd
->groups
[0].group
;
445 count2
= EXT4_CLUSTERS_PER_GROUP(sb
) - (first_cluster
- start
);
449 if (flex_gd
->bg_flags
[group
] & EXT4_BG_BLOCK_UNINIT
) {
450 BUG_ON(flex_gd
->count
> 1);
454 err
= extend_or_restart_transaction(handle
, 1);
458 bh
= sb_getblk(sb
, flex_gd
->groups
[group
].block_bitmap
);
462 BUFFER_TRACE(bh
, "get_write_access");
463 err
= ext4_journal_get_write_access(handle
, bh
);
468 ext4_debug("mark block bitmap %#04llx (+%llu/%u)\n",
469 first_cluster
, first_cluster
- start
, count2
);
470 ext4_set_bits(bh
->b_data
, first_cluster
- start
, count2
);
472 err
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
482 * Set up the block and inode bitmaps, and the inode table for the new groups.
483 * This doesn't need to be part of the main transaction, since we are only
484 * changing blocks outside the actual filesystem. We still do journaling to
485 * ensure the recovery is correct in case of a failure just after resize.
486 * If any part of this fails, we simply abort the resize.
488 * setup_new_flex_group_blocks handles a flex group as follow:
489 * 1. copy super block and GDT, and initialize group tables if necessary.
490 * In this step, we only set bits in blocks bitmaps for blocks taken by
491 * super block and GDT.
492 * 2. allocate group tables in block bitmaps, that is, set bits in block
493 * bitmap for blocks taken by group tables.
495 static int setup_new_flex_group_blocks(struct super_block
*sb
,
496 struct ext4_new_flex_group_data
*flex_gd
)
498 int group_table_count
[] = {1, 1, EXT4_SB(sb
)->s_itb_per_group
};
501 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
502 struct ext4_super_block
*es
= sbi
->s_es
;
503 struct ext4_new_group_data
*group_data
= flex_gd
->groups
;
504 __u16
*bg_flags
= flex_gd
->bg_flags
;
506 ext4_group_t group
, count
;
507 struct buffer_head
*bh
= NULL
;
508 int reserved_gdb
, i
, j
, err
= 0, err2
;
511 BUG_ON(!flex_gd
->count
|| !group_data
||
512 group_data
[0].group
!= sbi
->s_groups_count
);
514 reserved_gdb
= le16_to_cpu(es
->s_reserved_gdt_blocks
);
515 meta_bg
= ext4_has_feature_meta_bg(sb
);
517 /* This transaction may be extended/restarted along the way */
518 handle
= ext4_journal_start_sb(sb
, EXT4_HT_RESIZE
, EXT4_MAX_TRANS_DATA
);
520 return PTR_ERR(handle
);
522 group
= group_data
[0].group
;
523 for (i
= 0; i
< flex_gd
->count
; i
++, group
++) {
524 unsigned long gdblocks
;
525 ext4_grpblk_t overhead
;
527 gdblocks
= ext4_bg_num_gdb(sb
, group
);
528 start
= ext4_group_first_block_no(sb
, group
);
530 if (meta_bg
== 0 && !ext4_bg_has_super(sb
, group
))
534 ext4_group_t first_group
;
535 first_group
= ext4_meta_bg_first_group(sb
, group
);
536 if (first_group
!= group
+ 1 &&
537 first_group
!= group
+ EXT4_DESC_PER_BLOCK(sb
) - 1)
541 block
= start
+ ext4_bg_has_super(sb
, group
);
542 /* Copy all of the GDT blocks into the backup in this group */
543 for (j
= 0; j
< gdblocks
; j
++, block
++) {
544 struct buffer_head
*gdb
;
546 ext4_debug("update backup group %#04llx\n", block
);
547 err
= extend_or_restart_transaction(handle
, 1);
551 gdb
= sb_getblk(sb
, block
);
552 if (unlikely(!gdb
)) {
557 BUFFER_TRACE(gdb
, "get_write_access");
558 err
= ext4_journal_get_write_access(handle
, gdb
);
563 memcpy(gdb
->b_data
, sbi
->s_group_desc
[j
]->b_data
,
565 set_buffer_uptodate(gdb
);
567 err
= ext4_handle_dirty_metadata(handle
, NULL
, gdb
);
575 /* Zero out all of the reserved backup group descriptor
578 if (ext4_bg_has_super(sb
, group
)) {
579 err
= sb_issue_zeroout(sb
, gdblocks
+ start
+ 1,
580 reserved_gdb
, GFP_NOFS
);
586 /* Initialize group tables of the grop @group */
587 if (!(bg_flags
[i
] & EXT4_BG_INODE_ZEROED
))
590 /* Zero out all of the inode table blocks */
591 block
= group_data
[i
].inode_table
;
592 ext4_debug("clear inode table blocks %#04llx -> %#04lx\n",
593 block
, sbi
->s_itb_per_group
);
594 err
= sb_issue_zeroout(sb
, block
, sbi
->s_itb_per_group
,
600 if (bg_flags
[i
] & EXT4_BG_BLOCK_UNINIT
)
603 /* Initialize block bitmap of the @group */
604 block
= group_data
[i
].block_bitmap
;
605 err
= extend_or_restart_transaction(handle
, 1);
609 bh
= bclean(handle
, sb
, block
);
614 overhead
= ext4_group_overhead_blocks(sb
, group
);
616 ext4_debug("mark backup superblock %#04llx (+0)\n",
618 ext4_set_bits(bh
->b_data
, 0,
619 EXT4_NUM_B2C(sbi
, overhead
));
621 ext4_mark_bitmap_end(EXT4_B2C(sbi
, group_data
[i
].blocks_count
),
622 sb
->s_blocksize
* 8, bh
->b_data
);
623 err
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
629 if (bg_flags
[i
] & EXT4_BG_INODE_UNINIT
)
632 /* Initialize inode bitmap of the @group */
633 block
= group_data
[i
].inode_bitmap
;
634 err
= extend_or_restart_transaction(handle
, 1);
637 /* Mark unused entries in inode bitmap used */
638 bh
= bclean(handle
, sb
, block
);
644 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb
),
645 sb
->s_blocksize
* 8, bh
->b_data
);
646 err
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
652 /* Mark group tables in block bitmap */
653 for (j
= 0; j
< GROUP_TABLE_COUNT
; j
++) {
654 count
= group_table_count
[j
];
655 start
= (&group_data
[0].block_bitmap
)[j
];
657 for (i
= 1; i
< flex_gd
->count
; i
++) {
658 block
+= group_table_count
[j
];
659 if (block
== (&group_data
[i
].block_bitmap
)[j
]) {
660 count
+= group_table_count
[j
];
663 err
= set_flexbg_block_bitmap(sb
, handle
,
665 EXT4_B2C(sbi
, start
),
671 count
= group_table_count
[j
];
672 start
= (&group_data
[i
].block_bitmap
)[j
];
677 err
= set_flexbg_block_bitmap(sb
, handle
,
679 EXT4_B2C(sbi
, start
),
689 err2
= ext4_journal_stop(handle
);
697 * Iterate through the groups which hold BACKUP superblock/GDT copies in an
698 * ext4 filesystem. The counters should be initialized to 1, 5, and 7 before
699 * calling this for the first time. In a sparse filesystem it will be the
700 * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
701 * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
703 static unsigned ext4_list_backups(struct super_block
*sb
, unsigned *three
,
704 unsigned *five
, unsigned *seven
)
706 unsigned *min
= three
;
710 if (!ext4_has_feature_sparse_super(sb
)) {
732 * Check that all of the backup GDT blocks are held in the primary GDT block.
733 * It is assumed that they are stored in group order. Returns the number of
734 * groups in current filesystem that have BACKUPS, or -ve error code.
736 static int verify_reserved_gdb(struct super_block
*sb
,
738 struct buffer_head
*primary
)
740 const ext4_fsblk_t blk
= primary
->b_blocknr
;
745 __le32
*p
= (__le32
*)primary
->b_data
;
748 while ((grp
= ext4_list_backups(sb
, &three
, &five
, &seven
)) < end
) {
749 if (le32_to_cpu(*p
++) !=
750 grp
* EXT4_BLOCKS_PER_GROUP(sb
) + blk
){
751 ext4_warning(sb
, "reserved GDT %llu"
752 " missing grp %d (%llu)",
755 (ext4_fsblk_t
)EXT4_BLOCKS_PER_GROUP(sb
) +
759 if (++gdbackups
> EXT4_ADDR_PER_BLOCK(sb
))
767 * Called when we need to bring a reserved group descriptor table block into
768 * use from the resize inode. The primary copy of the new GDT block currently
769 * is an indirect block (under the double indirect block in the resize inode).
770 * The new backup GDT blocks will be stored as leaf blocks in this indirect
771 * block, in group order. Even though we know all the block numbers we need,
772 * we check to ensure that the resize inode has actually reserved these blocks.
774 * Don't need to update the block bitmaps because the blocks are still in use.
776 * We get all of the error cases out of the way, so that we are sure to not
777 * fail once we start modifying the data on disk, because JBD has no rollback.
779 static int add_new_gdb(handle_t
*handle
, struct inode
*inode
,
782 struct super_block
*sb
= inode
->i_sb
;
783 struct ext4_super_block
*es
= EXT4_SB(sb
)->s_es
;
784 unsigned long gdb_num
= group
/ EXT4_DESC_PER_BLOCK(sb
);
785 ext4_fsblk_t gdblock
= EXT4_SB(sb
)->s_sbh
->b_blocknr
+ 1 + gdb_num
;
786 struct buffer_head
**o_group_desc
, **n_group_desc
= NULL
;
787 struct buffer_head
*dind
= NULL
;
788 struct buffer_head
*gdb_bh
= NULL
;
790 struct ext4_iloc iloc
= { .bh
= NULL
};
794 if (test_opt(sb
, DEBUG
))
796 "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n",
799 gdb_bh
= ext4_sb_bread(sb
, gdblock
, 0);
801 return PTR_ERR(gdb_bh
);
803 gdbackups
= verify_reserved_gdb(sb
, group
, gdb_bh
);
809 data
= EXT4_I(inode
)->i_data
+ EXT4_DIND_BLOCK
;
810 dind
= ext4_sb_bread(sb
, le32_to_cpu(*data
), 0);
817 data
= (__le32
*)dind
->b_data
;
818 if (le32_to_cpu(data
[gdb_num
% EXT4_ADDR_PER_BLOCK(sb
)]) != gdblock
) {
819 ext4_warning(sb
, "new group %u GDT block %llu not reserved",
825 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get_write_access");
826 err
= ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
);
830 BUFFER_TRACE(gdb_bh
, "get_write_access");
831 err
= ext4_journal_get_write_access(handle
, gdb_bh
);
835 BUFFER_TRACE(dind
, "get_write_access");
836 err
= ext4_journal_get_write_access(handle
, dind
);
838 ext4_std_error(sb
, err
);
840 /* ext4_reserve_inode_write() gets a reference on the iloc */
841 err
= ext4_reserve_inode_write(handle
, inode
, &iloc
);
845 n_group_desc
= ext4_kvmalloc((gdb_num
+ 1) *
846 sizeof(struct buffer_head
*),
850 ext4_warning(sb
, "not enough memory for %lu groups",
856 * Finally, we have all of the possible failures behind us...
858 * Remove new GDT block from inode double-indirect block and clear out
859 * the new GDT block for use (which also "frees" the backup GDT blocks
860 * from the reserved inode). We don't need to change the bitmaps for
861 * these blocks, because they are marked as in-use from being in the
862 * reserved inode, and will become GDT blocks (primary and backup).
864 data
[gdb_num
% EXT4_ADDR_PER_BLOCK(sb
)] = 0;
865 err
= ext4_handle_dirty_metadata(handle
, NULL
, dind
);
867 ext4_std_error(sb
, err
);
870 inode
->i_blocks
-= (gdbackups
+ 1) * sb
->s_blocksize
>>
871 (9 - EXT4_SB(sb
)->s_cluster_bits
);
872 ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
873 memset(gdb_bh
->b_data
, 0, sb
->s_blocksize
);
874 err
= ext4_handle_dirty_metadata(handle
, NULL
, gdb_bh
);
876 ext4_std_error(sb
, err
);
881 o_group_desc
= EXT4_SB(sb
)->s_group_desc
;
882 memcpy(n_group_desc
, o_group_desc
,
883 EXT4_SB(sb
)->s_gdb_count
* sizeof(struct buffer_head
*));
884 n_group_desc
[gdb_num
] = gdb_bh
;
885 EXT4_SB(sb
)->s_group_desc
= n_group_desc
;
886 EXT4_SB(sb
)->s_gdb_count
++;
887 kvfree(o_group_desc
);
889 le16_add_cpu(&es
->s_reserved_gdt_blocks
, -1);
890 err
= ext4_handle_dirty_super(handle
, sb
);
892 ext4_std_error(sb
, err
);
895 kvfree(n_group_desc
);
900 ext4_debug("leaving with error %d\n", err
);
905 * add_new_gdb_meta_bg is the sister of add_new_gdb.
907 static int add_new_gdb_meta_bg(struct super_block
*sb
,
908 handle_t
*handle
, ext4_group_t group
) {
909 ext4_fsblk_t gdblock
;
910 struct buffer_head
*gdb_bh
;
911 struct buffer_head
**o_group_desc
, **n_group_desc
;
912 unsigned long gdb_num
= group
/ EXT4_DESC_PER_BLOCK(sb
);
915 gdblock
= ext4_meta_bg_first_block_no(sb
, group
) +
916 ext4_bg_has_super(sb
, group
);
917 gdb_bh
= ext4_sb_bread(sb
, gdblock
, 0);
919 return PTR_ERR(gdb_bh
);
920 n_group_desc
= ext4_kvmalloc((gdb_num
+ 1) *
921 sizeof(struct buffer_head
*),
926 ext4_warning(sb
, "not enough memory for %lu groups",
931 o_group_desc
= EXT4_SB(sb
)->s_group_desc
;
932 memcpy(n_group_desc
, o_group_desc
,
933 EXT4_SB(sb
)->s_gdb_count
* sizeof(struct buffer_head
*));
934 n_group_desc
[gdb_num
] = gdb_bh
;
936 BUFFER_TRACE(gdb_bh
, "get_write_access");
937 err
= ext4_journal_get_write_access(handle
, gdb_bh
);
939 kvfree(n_group_desc
);
944 EXT4_SB(sb
)->s_group_desc
= n_group_desc
;
945 EXT4_SB(sb
)->s_gdb_count
++;
946 kvfree(o_group_desc
);
951 * Called when we are adding a new group which has a backup copy of each of
952 * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
953 * We need to add these reserved backup GDT blocks to the resize inode, so
954 * that they are kept for future resizing and not allocated to files.
956 * Each reserved backup GDT block will go into a different indirect block.
957 * The indirect blocks are actually the primary reserved GDT blocks,
958 * so we know in advance what their block numbers are. We only get the
959 * double-indirect block to verify it is pointing to the primary reserved
960 * GDT blocks so we don't overwrite a data block by accident. The reserved
961 * backup GDT blocks are stored in their reserved primary GDT block.
963 static int reserve_backup_gdb(handle_t
*handle
, struct inode
*inode
,
966 struct super_block
*sb
= inode
->i_sb
;
967 int reserved_gdb
=le16_to_cpu(EXT4_SB(sb
)->s_es
->s_reserved_gdt_blocks
);
968 int cluster_bits
= EXT4_SB(sb
)->s_cluster_bits
;
969 struct buffer_head
**primary
;
970 struct buffer_head
*dind
;
971 struct ext4_iloc iloc
;
978 primary
= kmalloc_array(reserved_gdb
, sizeof(*primary
), GFP_NOFS
);
982 data
= EXT4_I(inode
)->i_data
+ EXT4_DIND_BLOCK
;
983 dind
= ext4_sb_bread(sb
, le32_to_cpu(*data
), 0);
990 blk
= EXT4_SB(sb
)->s_sbh
->b_blocknr
+ 1 + EXT4_SB(sb
)->s_gdb_count
;
991 data
= (__le32
*)dind
->b_data
+ (EXT4_SB(sb
)->s_gdb_count
%
992 EXT4_ADDR_PER_BLOCK(sb
));
993 end
= (__le32
*)dind
->b_data
+ EXT4_ADDR_PER_BLOCK(sb
);
995 /* Get each reserved primary GDT block and verify it holds backups */
996 for (res
= 0; res
< reserved_gdb
; res
++, blk
++) {
997 if (le32_to_cpu(*data
) != blk
) {
998 ext4_warning(sb
, "reserved block %llu"
999 " not at offset %ld",
1001 (long)(data
- (__le32
*)dind
->b_data
));
1005 primary
[res
] = ext4_sb_bread(sb
, blk
, 0);
1006 if (IS_ERR(primary
[res
])) {
1007 err
= PTR_ERR(primary
[res
]);
1008 primary
[res
] = NULL
;
1011 gdbackups
= verify_reserved_gdb(sb
, group
, primary
[res
]);
1012 if (gdbackups
< 0) {
1013 brelse(primary
[res
]);
1018 data
= (__le32
*)dind
->b_data
;
1021 for (i
= 0; i
< reserved_gdb
; i
++) {
1022 BUFFER_TRACE(primary
[i
], "get_write_access");
1023 if ((err
= ext4_journal_get_write_access(handle
, primary
[i
])))
1027 if ((err
= ext4_reserve_inode_write(handle
, inode
, &iloc
)))
1031 * Finally we can add each of the reserved backup GDT blocks from
1032 * the new group to its reserved primary GDT block.
1034 blk
= group
* EXT4_BLOCKS_PER_GROUP(sb
);
1035 for (i
= 0; i
< reserved_gdb
; i
++) {
1037 data
= (__le32
*)primary
[i
]->b_data
;
1038 /* printk("reserving backup %lu[%u] = %lu\n",
1039 primary[i]->b_blocknr, gdbackups,
1040 blk + primary[i]->b_blocknr); */
1041 data
[gdbackups
] = cpu_to_le32(blk
+ primary
[i
]->b_blocknr
);
1042 err2
= ext4_handle_dirty_metadata(handle
, NULL
, primary
[i
]);
1047 inode
->i_blocks
+= reserved_gdb
* sb
->s_blocksize
>> (9 - cluster_bits
);
1048 ext4_mark_iloc_dirty(handle
, inode
, &iloc
);
1052 brelse(primary
[res
]);
1062 * Update the backup copies of the ext4 metadata. These don't need to be part
1063 * of the main resize transaction, because e2fsck will re-write them if there
1064 * is a problem (basically only OOM will cause a problem). However, we
1065 * _should_ update the backups if possible, in case the primary gets trashed
1066 * for some reason and we need to run e2fsck from a backup superblock. The
1067 * important part is that the new block and inode counts are in the backup
1068 * superblocks, and the location of the new group metadata in the GDT backups.
1070 * We do not need take the s_resize_lock for this, because these
1071 * blocks are not otherwise touched by the filesystem code when it is
1072 * mounted. We don't need to worry about last changing from
1073 * sbi->s_groups_count, because the worst that can happen is that we
1074 * do not copy the full number of backups at this time. The resize
1075 * which changed s_groups_count will backup again.
1077 static void update_backups(struct super_block
*sb
, sector_t blk_off
, char *data
,
1078 int size
, int meta_bg
)
1080 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1082 const int bpg
= EXT4_BLOCKS_PER_GROUP(sb
);
1086 ext4_group_t group
= 0;
1087 int rest
= sb
->s_blocksize
- size
;
1091 handle
= ext4_journal_start_sb(sb
, EXT4_HT_RESIZE
, EXT4_MAX_TRANS_DATA
);
1092 if (IS_ERR(handle
)) {
1094 err
= PTR_ERR(handle
);
1099 group
= ext4_list_backups(sb
, &three
, &five
, &seven
);
1100 last
= sbi
->s_groups_count
;
1102 group
= ext4_get_group_number(sb
, blk_off
) + 1;
1103 last
= (ext4_group_t
)(group
+ EXT4_DESC_PER_BLOCK(sb
) - 2);
1106 while (group
< sbi
->s_groups_count
) {
1107 struct buffer_head
*bh
;
1108 ext4_fsblk_t backup_block
;
1110 /* Out of journal space, and can't get more - abort - so sad */
1111 if (ext4_handle_valid(handle
) &&
1112 handle
->h_buffer_credits
== 0 &&
1113 ext4_journal_extend(handle
, EXT4_MAX_TRANS_DATA
) &&
1114 (err
= ext4_journal_restart(handle
, EXT4_MAX_TRANS_DATA
)))
1118 backup_block
= ((ext4_fsblk_t
)group
) * bpg
+ blk_off
;
1120 backup_block
= (ext4_group_first_block_no(sb
, group
) +
1121 ext4_bg_has_super(sb
, group
));
1123 bh
= sb_getblk(sb
, backup_block
);
1124 if (unlikely(!bh
)) {
1128 ext4_debug("update metadata backup %llu(+%llu)\n",
1129 backup_block
, backup_block
-
1130 ext4_group_first_block_no(sb
, group
));
1131 BUFFER_TRACE(bh
, "get_write_access");
1132 if ((err
= ext4_journal_get_write_access(handle
, bh
))) {
1137 memcpy(bh
->b_data
, data
, size
);
1139 memset(bh
->b_data
+ size
, 0, rest
);
1140 set_buffer_uptodate(bh
);
1142 err
= ext4_handle_dirty_metadata(handle
, NULL
, bh
);
1144 ext4_std_error(sb
, err
);
1148 group
= ext4_list_backups(sb
, &three
, &five
, &seven
);
1149 else if (group
== last
)
1154 if ((err2
= ext4_journal_stop(handle
)) && !err
)
1158 * Ugh! Need to have e2fsck write the backup copies. It is too
1159 * late to revert the resize, we shouldn't fail just because of
1160 * the backup copies (they are only needed in case of corruption).
1162 * However, if we got here we have a journal problem too, so we
1163 * can't really start a transaction to mark the superblock.
1164 * Chicken out and just set the flag on the hope it will be written
1165 * to disk, and if not - we will simply wait until next fsck.
1169 ext4_warning(sb
, "can't update backup for group %u (err %d), "
1170 "forcing fsck on next reboot", group
, err
);
1171 sbi
->s_mount_state
&= ~EXT4_VALID_FS
;
1172 sbi
->s_es
->s_state
&= cpu_to_le16(~EXT4_VALID_FS
);
1173 mark_buffer_dirty(sbi
->s_sbh
);
1178 * ext4_add_new_descs() adds @count group descriptor of groups
1179 * starting at @group
1181 * @handle: journal handle
1183 * @group: the group no. of the first group desc to be added
1184 * @resize_inode: the resize inode
1185 * @count: number of group descriptors to be added
1187 static int ext4_add_new_descs(handle_t
*handle
, struct super_block
*sb
,
1188 ext4_group_t group
, struct inode
*resize_inode
,
1191 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1192 struct ext4_super_block
*es
= sbi
->s_es
;
1193 struct buffer_head
*gdb_bh
;
1194 int i
, gdb_off
, gdb_num
, err
= 0;
1197 meta_bg
= ext4_has_feature_meta_bg(sb
);
1198 for (i
= 0; i
< count
; i
++, group
++) {
1199 int reserved_gdb
= ext4_bg_has_super(sb
, group
) ?
1200 le16_to_cpu(es
->s_reserved_gdt_blocks
) : 0;
1202 gdb_off
= group
% EXT4_DESC_PER_BLOCK(sb
);
1203 gdb_num
= group
/ EXT4_DESC_PER_BLOCK(sb
);
1206 * We will only either add reserved group blocks to a backup group
1207 * or remove reserved blocks for the first group in a new group block.
1208 * Doing both would be mean more complex code, and sane people don't
1209 * use non-sparse filesystems anymore. This is already checked above.
1212 gdb_bh
= sbi
->s_group_desc
[gdb_num
];
1213 BUFFER_TRACE(gdb_bh
, "get_write_access");
1214 err
= ext4_journal_get_write_access(handle
, gdb_bh
);
1216 if (!err
&& reserved_gdb
&& ext4_bg_num_gdb(sb
, group
))
1217 err
= reserve_backup_gdb(handle
, resize_inode
, group
);
1218 } else if (meta_bg
!= 0) {
1219 err
= add_new_gdb_meta_bg(sb
, handle
, group
);
1221 err
= add_new_gdb(handle
, resize_inode
, group
);
1229 static struct buffer_head
*ext4_get_bitmap(struct super_block
*sb
, __u64 block
)
1231 struct buffer_head
*bh
= sb_getblk(sb
, block
);
1234 if (!bh_uptodate_or_lock(bh
)) {
1235 if (bh_submit_read(bh
) < 0) {
1244 static int ext4_set_bitmap_checksums(struct super_block
*sb
,
1246 struct ext4_group_desc
*gdp
,
1247 struct ext4_new_group_data
*group_data
)
1249 struct buffer_head
*bh
;
1251 if (!ext4_has_metadata_csum(sb
))
1254 bh
= ext4_get_bitmap(sb
, group_data
->inode_bitmap
);
1257 ext4_inode_bitmap_csum_set(sb
, group
, gdp
, bh
,
1258 EXT4_INODES_PER_GROUP(sb
) / 8);
1261 bh
= ext4_get_bitmap(sb
, group_data
->block_bitmap
);
1264 ext4_block_bitmap_csum_set(sb
, group
, gdp
, bh
);
1271 * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg
1273 static int ext4_setup_new_descs(handle_t
*handle
, struct super_block
*sb
,
1274 struct ext4_new_flex_group_data
*flex_gd
)
1276 struct ext4_new_group_data
*group_data
= flex_gd
->groups
;
1277 struct ext4_group_desc
*gdp
;
1278 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1279 struct buffer_head
*gdb_bh
;
1281 __u16
*bg_flags
= flex_gd
->bg_flags
;
1282 int i
, gdb_off
, gdb_num
, err
= 0;
1285 for (i
= 0; i
< flex_gd
->count
; i
++, group_data
++, bg_flags
++) {
1286 group
= group_data
->group
;
1288 gdb_off
= group
% EXT4_DESC_PER_BLOCK(sb
);
1289 gdb_num
= group
/ EXT4_DESC_PER_BLOCK(sb
);
1292 * get_write_access() has been called on gdb_bh by ext4_add_new_desc().
1294 gdb_bh
= sbi
->s_group_desc
[gdb_num
];
1295 /* Update group descriptor block for new group */
1296 gdp
= (struct ext4_group_desc
*)(gdb_bh
->b_data
+
1297 gdb_off
* EXT4_DESC_SIZE(sb
));
1299 memset(gdp
, 0, EXT4_DESC_SIZE(sb
));
1300 ext4_block_bitmap_set(sb
, gdp
, group_data
->block_bitmap
);
1301 ext4_inode_bitmap_set(sb
, gdp
, group_data
->inode_bitmap
);
1302 err
= ext4_set_bitmap_checksums(sb
, group
, gdp
, group_data
);
1304 ext4_std_error(sb
, err
);
1308 ext4_inode_table_set(sb
, gdp
, group_data
->inode_table
);
1309 ext4_free_group_clusters_set(sb
, gdp
,
1310 group_data
->free_clusters_count
);
1311 ext4_free_inodes_set(sb
, gdp
, EXT4_INODES_PER_GROUP(sb
));
1312 if (ext4_has_group_desc_csum(sb
))
1313 ext4_itable_unused_set(sb
, gdp
,
1314 EXT4_INODES_PER_GROUP(sb
));
1315 gdp
->bg_flags
= cpu_to_le16(*bg_flags
);
1316 ext4_group_desc_csum_set(sb
, group
, gdp
);
1318 err
= ext4_handle_dirty_metadata(handle
, NULL
, gdb_bh
);
1319 if (unlikely(err
)) {
1320 ext4_std_error(sb
, err
);
1325 * We can allocate memory for mb_alloc based on the new group
1328 err
= ext4_mb_add_groupinfo(sb
, group
, gdp
);
1336 * ext4_update_super() updates the super block so that the newly added
1337 * groups can be seen by the filesystem.
1340 * @flex_gd: new added groups
1342 static void ext4_update_super(struct super_block
*sb
,
1343 struct ext4_new_flex_group_data
*flex_gd
)
1345 ext4_fsblk_t blocks_count
= 0;
1346 ext4_fsblk_t free_blocks
= 0;
1347 ext4_fsblk_t reserved_blocks
= 0;
1348 struct ext4_new_group_data
*group_data
= flex_gd
->groups
;
1349 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1350 struct ext4_super_block
*es
= sbi
->s_es
;
1353 BUG_ON(flex_gd
->count
== 0 || group_data
== NULL
);
1355 * Make the new blocks and inodes valid next. We do this before
1356 * increasing the group count so that once the group is enabled,
1357 * all of its blocks and inodes are already valid.
1359 * We always allocate group-by-group, then block-by-block or
1360 * inode-by-inode within a group, so enabling these
1361 * blocks/inodes before the group is live won't actually let us
1362 * allocate the new space yet.
1364 for (i
= 0; i
< flex_gd
->count
; i
++) {
1365 blocks_count
+= group_data
[i
].blocks_count
;
1366 free_blocks
+= EXT4_C2B(sbi
, group_data
[i
].free_clusters_count
);
1369 reserved_blocks
= ext4_r_blocks_count(es
) * 100;
1370 reserved_blocks
= div64_u64(reserved_blocks
, ext4_blocks_count(es
));
1371 reserved_blocks
*= blocks_count
;
1372 do_div(reserved_blocks
, 100);
1374 ext4_blocks_count_set(es
, ext4_blocks_count(es
) + blocks_count
);
1375 ext4_free_blocks_count_set(es
, ext4_free_blocks_count(es
) + free_blocks
);
1376 le32_add_cpu(&es
->s_inodes_count
, EXT4_INODES_PER_GROUP(sb
) *
1378 le32_add_cpu(&es
->s_free_inodes_count
, EXT4_INODES_PER_GROUP(sb
) *
1381 ext4_debug("free blocks count %llu", ext4_free_blocks_count(es
));
1383 * We need to protect s_groups_count against other CPUs seeing
1384 * inconsistent state in the superblock.
1386 * The precise rules we use are:
1388 * * Writers must perform a smp_wmb() after updating all
1389 * dependent data and before modifying the groups count
1391 * * Readers must perform an smp_rmb() after reading the groups
1392 * count and before reading any dependent data.
1394 * NB. These rules can be relaxed when checking the group count
1395 * while freeing data, as we can only allocate from a block
1396 * group after serialising against the group count, and we can
1397 * only then free after serialising in turn against that
1402 /* Update the global fs size fields */
1403 sbi
->s_groups_count
+= flex_gd
->count
;
1404 sbi
->s_blockfile_groups
= min_t(ext4_group_t
, sbi
->s_groups_count
,
1405 (EXT4_MAX_BLOCK_FILE_PHYS
/ EXT4_BLOCKS_PER_GROUP(sb
)));
1407 /* Update the reserved block counts only once the new group is
1409 ext4_r_blocks_count_set(es
, ext4_r_blocks_count(es
) +
1412 /* Update the free space counts */
1413 percpu_counter_add(&sbi
->s_freeclusters_counter
,
1414 EXT4_NUM_B2C(sbi
, free_blocks
));
1415 percpu_counter_add(&sbi
->s_freeinodes_counter
,
1416 EXT4_INODES_PER_GROUP(sb
) * flex_gd
->count
);
1418 ext4_debug("free blocks count %llu",
1419 percpu_counter_read(&sbi
->s_freeclusters_counter
));
1420 if (ext4_has_feature_flex_bg(sb
) && sbi
->s_log_groups_per_flex
) {
1421 ext4_group_t flex_group
;
1422 flex_group
= ext4_flex_group(sbi
, group_data
[0].group
);
1423 atomic64_add(EXT4_NUM_B2C(sbi
, free_blocks
),
1424 &sbi
->s_flex_groups
[flex_group
].free_clusters
);
1425 atomic_add(EXT4_INODES_PER_GROUP(sb
) * flex_gd
->count
,
1426 &sbi
->s_flex_groups
[flex_group
].free_inodes
);
1430 * Update the fs overhead information
1432 ext4_calculate_overhead(sb
);
1434 if (test_opt(sb
, DEBUG
))
1435 printk(KERN_DEBUG
"EXT4-fs: added group %u:"
1436 "%llu blocks(%llu free %llu reserved)\n", flex_gd
->count
,
1437 blocks_count
, free_blocks
, reserved_blocks
);
1440 /* Add a flex group to an fs. Ensure we handle all possible error conditions
1441 * _before_ we start modifying the filesystem, because we cannot abort the
1442 * transaction and not have it write the data to disk.
1444 static int ext4_flex_group_add(struct super_block
*sb
,
1445 struct inode
*resize_inode
,
1446 struct ext4_new_flex_group_data
*flex_gd
)
1448 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1449 struct ext4_super_block
*es
= sbi
->s_es
;
1450 ext4_fsblk_t o_blocks_count
;
1454 unsigned reserved_gdb
;
1455 int err
= 0, err2
= 0, credit
;
1457 BUG_ON(!flex_gd
->count
|| !flex_gd
->groups
|| !flex_gd
->bg_flags
);
1459 reserved_gdb
= le16_to_cpu(es
->s_reserved_gdt_blocks
);
1460 o_blocks_count
= ext4_blocks_count(es
);
1461 ext4_get_group_no_and_offset(sb
, o_blocks_count
, &group
, &last
);
1464 err
= setup_new_flex_group_blocks(sb
, flex_gd
);
1468 * We will always be modifying at least the superblock and GDT
1469 * blocks. If we are adding a group past the last current GDT block,
1470 * we will also modify the inode and the dindirect block. If we
1471 * are adding a group with superblock/GDT backups we will also
1472 * modify each of the reserved GDT dindirect blocks.
1474 credit
= 3; /* sb, resize inode, resize inode dindirect */
1476 credit
+= 1 + DIV_ROUND_UP(flex_gd
->count
, EXT4_DESC_PER_BLOCK(sb
));
1477 credit
+= reserved_gdb
; /* Reserved GDT dindirect blocks */
1478 handle
= ext4_journal_start_sb(sb
, EXT4_HT_RESIZE
, credit
);
1479 if (IS_ERR(handle
)) {
1480 err
= PTR_ERR(handle
);
1484 BUFFER_TRACE(sbi
->s_sbh
, "get_write_access");
1485 err
= ext4_journal_get_write_access(handle
, sbi
->s_sbh
);
1489 group
= flex_gd
->groups
[0].group
;
1490 BUG_ON(group
!= sbi
->s_groups_count
);
1491 err
= ext4_add_new_descs(handle
, sb
, group
,
1492 resize_inode
, flex_gd
->count
);
1496 err
= ext4_setup_new_descs(handle
, sb
, flex_gd
);
1500 ext4_update_super(sb
, flex_gd
);
1502 err
= ext4_handle_dirty_super(handle
, sb
);
1505 err2
= ext4_journal_stop(handle
);
1510 int gdb_num
= group
/ EXT4_DESC_PER_BLOCK(sb
);
1511 int gdb_num_end
= ((group
+ flex_gd
->count
- 1) /
1512 EXT4_DESC_PER_BLOCK(sb
));
1513 int meta_bg
= ext4_has_feature_meta_bg(sb
);
1514 sector_t old_gdb
= 0;
1516 update_backups(sb
, sbi
->s_sbh
->b_blocknr
, (char *)es
,
1517 sizeof(struct ext4_super_block
), 0);
1518 for (; gdb_num
<= gdb_num_end
; gdb_num
++) {
1519 struct buffer_head
*gdb_bh
;
1521 gdb_bh
= sbi
->s_group_desc
[gdb_num
];
1522 if (old_gdb
== gdb_bh
->b_blocknr
)
1524 update_backups(sb
, gdb_bh
->b_blocknr
, gdb_bh
->b_data
,
1525 gdb_bh
->b_size
, meta_bg
);
1526 old_gdb
= gdb_bh
->b_blocknr
;
1533 static int ext4_setup_next_flex_gd(struct super_block
*sb
,
1534 struct ext4_new_flex_group_data
*flex_gd
,
1535 ext4_fsblk_t n_blocks_count
,
1536 unsigned long flexbg_size
)
1538 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1539 struct ext4_super_block
*es
= sbi
->s_es
;
1540 struct ext4_new_group_data
*group_data
= flex_gd
->groups
;
1541 ext4_fsblk_t o_blocks_count
;
1542 ext4_group_t n_group
;
1544 ext4_group_t last_group
;
1546 ext4_grpblk_t clusters_per_group
;
1549 clusters_per_group
= EXT4_CLUSTERS_PER_GROUP(sb
);
1551 o_blocks_count
= ext4_blocks_count(es
);
1553 if (o_blocks_count
== n_blocks_count
)
1556 ext4_get_group_no_and_offset(sb
, o_blocks_count
, &group
, &last
);
1558 ext4_get_group_no_and_offset(sb
, n_blocks_count
- 1, &n_group
, &last
);
1560 last_group
= group
| (flexbg_size
- 1);
1561 if (last_group
> n_group
)
1562 last_group
= n_group
;
1564 flex_gd
->count
= last_group
- group
+ 1;
1566 for (i
= 0; i
< flex_gd
->count
; i
++) {
1569 group_data
[i
].group
= group
+ i
;
1570 group_data
[i
].blocks_count
= EXT4_BLOCKS_PER_GROUP(sb
);
1571 overhead
= ext4_group_overhead_blocks(sb
, group
+ i
);
1572 group_data
[i
].mdata_blocks
= overhead
;
1573 group_data
[i
].free_clusters_count
= EXT4_CLUSTERS_PER_GROUP(sb
);
1574 if (ext4_has_group_desc_csum(sb
)) {
1575 flex_gd
->bg_flags
[i
] = EXT4_BG_BLOCK_UNINIT
|
1576 EXT4_BG_INODE_UNINIT
;
1577 if (!test_opt(sb
, INIT_INODE_TABLE
))
1578 flex_gd
->bg_flags
[i
] |= EXT4_BG_INODE_ZEROED
;
1580 flex_gd
->bg_flags
[i
] = EXT4_BG_INODE_ZEROED
;
1583 if (last_group
== n_group
&& ext4_has_group_desc_csum(sb
))
1584 /* We need to initialize block bitmap of last group. */
1585 flex_gd
->bg_flags
[i
- 1] &= ~EXT4_BG_BLOCK_UNINIT
;
1587 if ((last_group
== n_group
) && (last
!= clusters_per_group
- 1)) {
1588 group_data
[i
- 1].blocks_count
= EXT4_C2B(sbi
, last
+ 1);
1589 group_data
[i
- 1].free_clusters_count
-= clusters_per_group
-
1596 /* Add group descriptor data to an existing or new group descriptor block.
1597 * Ensure we handle all possible error conditions _before_ we start modifying
1598 * the filesystem, because we cannot abort the transaction and not have it
1599 * write the data to disk.
1601 * If we are on a GDT block boundary, we need to get the reserved GDT block.
1602 * Otherwise, we may need to add backup GDT blocks for a sparse group.
1604 * We only need to hold the superblock lock while we are actually adding
1605 * in the new group's counts to the superblock. Prior to that we have
1606 * not really "added" the group at all. We re-check that we are still
1607 * adding in the last group in case things have changed since verifying.
1609 int ext4_group_add(struct super_block
*sb
, struct ext4_new_group_data
*input
)
1611 struct ext4_new_flex_group_data flex_gd
;
1612 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1613 struct ext4_super_block
*es
= sbi
->s_es
;
1614 int reserved_gdb
= ext4_bg_has_super(sb
, input
->group
) ?
1615 le16_to_cpu(es
->s_reserved_gdt_blocks
) : 0;
1616 struct inode
*inode
= NULL
;
1621 gdb_off
= input
->group
% EXT4_DESC_PER_BLOCK(sb
);
1623 if (gdb_off
== 0 && !ext4_has_feature_sparse_super(sb
)) {
1624 ext4_warning(sb
, "Can't resize non-sparse filesystem further");
1628 if (ext4_blocks_count(es
) + input
->blocks_count
<
1629 ext4_blocks_count(es
)) {
1630 ext4_warning(sb
, "blocks_count overflow");
1634 if (le32_to_cpu(es
->s_inodes_count
) + EXT4_INODES_PER_GROUP(sb
) <
1635 le32_to_cpu(es
->s_inodes_count
)) {
1636 ext4_warning(sb
, "inodes_count overflow");
1640 if (reserved_gdb
|| gdb_off
== 0) {
1641 if (!ext4_has_feature_resize_inode(sb
) ||
1642 !le16_to_cpu(es
->s_reserved_gdt_blocks
)) {
1644 "No reserved GDT blocks, can't resize");
1647 inode
= ext4_iget(sb
, EXT4_RESIZE_INO
, EXT4_IGET_SPECIAL
);
1648 if (IS_ERR(inode
)) {
1649 ext4_warning(sb
, "Error opening resize inode");
1650 return PTR_ERR(inode
);
1655 err
= verify_group_input(sb
, input
);
1659 err
= ext4_alloc_flex_bg_array(sb
, input
->group
+ 1);
1663 err
= ext4_mb_alloc_groupinfo(sb
, input
->group
+ 1);
1668 flex_gd
.groups
= input
;
1669 flex_gd
.bg_flags
= &bg_flags
;
1670 err
= ext4_flex_group_add(sb
, inode
, &flex_gd
);
1674 } /* ext4_group_add */
1677 * extend a group without checking assuming that checking has been done.
1679 static int ext4_group_extend_no_check(struct super_block
*sb
,
1680 ext4_fsblk_t o_blocks_count
, ext4_grpblk_t add
)
1682 struct ext4_super_block
*es
= EXT4_SB(sb
)->s_es
;
1686 /* We will update the superblock, one block bitmap, and
1687 * one group descriptor via ext4_group_add_blocks().
1689 handle
= ext4_journal_start_sb(sb
, EXT4_HT_RESIZE
, 3);
1690 if (IS_ERR(handle
)) {
1691 err
= PTR_ERR(handle
);
1692 ext4_warning(sb
, "error %d on journal start", err
);
1696 BUFFER_TRACE(EXT4_SB(sb
)->s_sbh
, "get_write_access");
1697 err
= ext4_journal_get_write_access(handle
, EXT4_SB(sb
)->s_sbh
);
1699 ext4_warning(sb
, "error %d on journal write access", err
);
1703 ext4_blocks_count_set(es
, o_blocks_count
+ add
);
1704 ext4_free_blocks_count_set(es
, ext4_free_blocks_count(es
) + add
);
1705 ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count
,
1706 o_blocks_count
+ add
);
1707 /* We add the blocks to the bitmap and set the group need init bit */
1708 err
= ext4_group_add_blocks(handle
, sb
, o_blocks_count
, add
);
1711 ext4_handle_dirty_super(handle
, sb
);
1712 ext4_debug("freed blocks %llu through %llu\n", o_blocks_count
,
1713 o_blocks_count
+ add
);
1715 err2
= ext4_journal_stop(handle
);
1720 if (test_opt(sb
, DEBUG
))
1721 printk(KERN_DEBUG
"EXT4-fs: extended group to %llu "
1722 "blocks\n", ext4_blocks_count(es
));
1723 update_backups(sb
, EXT4_SB(sb
)->s_sbh
->b_blocknr
,
1724 (char *)es
, sizeof(struct ext4_super_block
), 0);
1730 * Extend the filesystem to the new number of blocks specified. This entry
1731 * point is only used to extend the current filesystem to the end of the last
1732 * existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
1733 * for emergencies (because it has no dependencies on reserved blocks).
1735 * If we _really_ wanted, we could use default values to call ext4_group_add()
1736 * allow the "remount" trick to work for arbitrary resizing, assuming enough
1737 * GDT blocks are reserved to grow to the desired size.
1739 int ext4_group_extend(struct super_block
*sb
, struct ext4_super_block
*es
,
1740 ext4_fsblk_t n_blocks_count
)
1742 ext4_fsblk_t o_blocks_count
;
1745 struct buffer_head
*bh
;
1749 o_blocks_count
= ext4_blocks_count(es
);
1751 if (test_opt(sb
, DEBUG
))
1752 ext4_msg(sb
, KERN_DEBUG
,
1753 "extending last group from %llu to %llu blocks",
1754 o_blocks_count
, n_blocks_count
);
1756 if (n_blocks_count
== 0 || n_blocks_count
== o_blocks_count
)
1759 if (n_blocks_count
> (sector_t
)(~0ULL) >> (sb
->s_blocksize_bits
- 9)) {
1760 ext4_msg(sb
, KERN_ERR
,
1761 "filesystem too large to resize to %llu blocks safely",
1766 if (n_blocks_count
< o_blocks_count
) {
1767 ext4_warning(sb
, "can't shrink FS - resize aborted");
1771 /* Handle the remaining blocks in the last group only. */
1772 ext4_get_group_no_and_offset(sb
, o_blocks_count
, &group
, &last
);
1775 ext4_warning(sb
, "need to use ext2online to resize further");
1779 add
= EXT4_BLOCKS_PER_GROUP(sb
) - last
;
1781 if (o_blocks_count
+ add
< o_blocks_count
) {
1782 ext4_warning(sb
, "blocks_count overflow");
1786 if (o_blocks_count
+ add
> n_blocks_count
)
1787 add
= n_blocks_count
- o_blocks_count
;
1789 if (o_blocks_count
+ add
< n_blocks_count
)
1790 ext4_warning(sb
, "will only finish group (%llu blocks, %u new)",
1791 o_blocks_count
+ add
, add
);
1793 /* See if the device is actually as big as what was requested */
1794 bh
= sb_bread(sb
, o_blocks_count
+ add
- 1);
1796 ext4_warning(sb
, "can't read last block, resize aborted");
1801 err
= ext4_group_extend_no_check(sb
, o_blocks_count
, add
);
1803 } /* ext4_group_extend */
1806 static int num_desc_blocks(struct super_block
*sb
, ext4_group_t groups
)
1808 return (groups
+ EXT4_DESC_PER_BLOCK(sb
) - 1) / EXT4_DESC_PER_BLOCK(sb
);
1812 * Release the resize inode and drop the resize_inode feature if there
1813 * are no more reserved gdt blocks, and then convert the file system
1816 static int ext4_convert_meta_bg(struct super_block
*sb
, struct inode
*inode
)
1819 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1820 struct ext4_super_block
*es
= sbi
->s_es
;
1821 struct ext4_inode_info
*ei
= EXT4_I(inode
);
1823 int i
, ret
, err
= 0;
1826 ext4_msg(sb
, KERN_INFO
, "Converting file system to meta_bg");
1828 if (es
->s_reserved_gdt_blocks
) {
1829 ext4_error(sb
, "Unexpected non-zero "
1830 "s_reserved_gdt_blocks");
1834 /* Do a quick sanity check of the resize inode */
1835 if (inode
->i_blocks
!= 1 << (inode
->i_blkbits
-
1836 (9 - sbi
->s_cluster_bits
)))
1837 goto invalid_resize_inode
;
1838 for (i
= 0; i
< EXT4_N_BLOCKS
; i
++) {
1839 if (i
== EXT4_DIND_BLOCK
) {
1843 goto invalid_resize_inode
;
1846 goto invalid_resize_inode
;
1848 credits
+= 3; /* block bitmap, bg descriptor, resize inode */
1851 handle
= ext4_journal_start_sb(sb
, EXT4_HT_RESIZE
, credits
);
1853 return PTR_ERR(handle
);
1855 BUFFER_TRACE(sbi
->s_sbh
, "get_write_access");
1856 err
= ext4_journal_get_write_access(handle
, sbi
->s_sbh
);
1860 ext4_clear_feature_resize_inode(sb
);
1861 ext4_set_feature_meta_bg(sb
);
1862 sbi
->s_es
->s_first_meta_bg
=
1863 cpu_to_le32(num_desc_blocks(sb
, sbi
->s_groups_count
));
1865 err
= ext4_handle_dirty_super(handle
, sb
);
1867 ext4_std_error(sb
, err
);
1872 nr
= le32_to_cpu(ei
->i_data
[EXT4_DIND_BLOCK
]);
1873 ext4_free_blocks(handle
, inode
, NULL
, nr
, 1,
1874 EXT4_FREE_BLOCKS_METADATA
|
1875 EXT4_FREE_BLOCKS_FORGET
);
1876 ei
->i_data
[EXT4_DIND_BLOCK
] = 0;
1877 inode
->i_blocks
= 0;
1879 err
= ext4_mark_inode_dirty(handle
, inode
);
1881 ext4_std_error(sb
, err
);
1885 ret
= ext4_journal_stop(handle
);
1890 invalid_resize_inode
:
1891 ext4_error(sb
, "corrupted/inconsistent resize inode");
1896 * ext4_resize_fs() resizes a fs to new size specified by @n_blocks_count
1898 * @sb: super block of the fs to be resized
1899 * @n_blocks_count: the number of blocks resides in the resized fs
1901 int ext4_resize_fs(struct super_block
*sb
, ext4_fsblk_t n_blocks_count
)
1903 struct ext4_new_flex_group_data
*flex_gd
= NULL
;
1904 struct ext4_sb_info
*sbi
= EXT4_SB(sb
);
1905 struct ext4_super_block
*es
= sbi
->s_es
;
1906 struct buffer_head
*bh
;
1907 struct inode
*resize_inode
= NULL
;
1908 ext4_grpblk_t add
, offset
;
1909 unsigned long n_desc_blocks
;
1910 unsigned long o_desc_blocks
;
1911 ext4_group_t o_group
;
1912 ext4_group_t n_group
;
1913 ext4_fsblk_t o_blocks_count
;
1914 ext4_fsblk_t n_blocks_count_retry
= 0;
1915 unsigned long last_update_time
= 0;
1916 int err
= 0, flexbg_size
= 1 << sbi
->s_log_groups_per_flex
;
1919 /* See if the device is actually as big as what was requested */
1920 bh
= sb_bread(sb
, n_blocks_count
- 1);
1922 ext4_warning(sb
, "can't read last block, resize aborted");
1928 o_blocks_count
= ext4_blocks_count(es
);
1930 ext4_msg(sb
, KERN_INFO
, "resizing filesystem from %llu "
1931 "to %llu blocks", o_blocks_count
, n_blocks_count
);
1933 if (n_blocks_count
< o_blocks_count
) {
1934 /* On-line shrinking not supported */
1935 ext4_warning(sb
, "can't shrink FS - resize aborted");
1939 if (n_blocks_count
== o_blocks_count
)
1940 /* Nothing need to do */
1943 n_group
= ext4_get_group_number(sb
, n_blocks_count
- 1);
1944 if (n_group
>= (0xFFFFFFFFUL
/ EXT4_INODES_PER_GROUP(sb
))) {
1945 ext4_warning(sb
, "resize would cause inodes_count overflow");
1948 ext4_get_group_no_and_offset(sb
, o_blocks_count
- 1, &o_group
, &offset
);
1950 n_desc_blocks
= num_desc_blocks(sb
, n_group
+ 1);
1951 o_desc_blocks
= num_desc_blocks(sb
, sbi
->s_groups_count
);
1953 meta_bg
= ext4_has_feature_meta_bg(sb
);
1955 if (ext4_has_feature_resize_inode(sb
)) {
1957 ext4_error(sb
, "resize_inode and meta_bg enabled "
1961 if (n_desc_blocks
> o_desc_blocks
+
1962 le16_to_cpu(es
->s_reserved_gdt_blocks
)) {
1963 n_blocks_count_retry
= n_blocks_count
;
1964 n_desc_blocks
= o_desc_blocks
+
1965 le16_to_cpu(es
->s_reserved_gdt_blocks
);
1966 n_group
= n_desc_blocks
* EXT4_DESC_PER_BLOCK(sb
);
1967 n_blocks_count
= (ext4_fsblk_t
)n_group
*
1968 EXT4_BLOCKS_PER_GROUP(sb
) +
1969 le32_to_cpu(es
->s_first_data_block
);
1970 n_group
--; /* set to last group number */
1974 resize_inode
= ext4_iget(sb
, EXT4_RESIZE_INO
,
1976 if (IS_ERR(resize_inode
)) {
1977 ext4_warning(sb
, "Error opening resize inode");
1978 return PTR_ERR(resize_inode
);
1982 if ((!resize_inode
&& !meta_bg
) || n_blocks_count
== o_blocks_count
) {
1983 err
= ext4_convert_meta_bg(sb
, resize_inode
);
1988 resize_inode
= NULL
;
1990 if (n_blocks_count_retry
) {
1991 n_blocks_count
= n_blocks_count_retry
;
1992 n_blocks_count_retry
= 0;
1998 * Make sure the last group has enough space so that it's
1999 * guaranteed to have enough space for all metadata blocks
2000 * that it might need to hold. (We might not need to store
2001 * the inode table blocks in the last block group, but there
2002 * will be cases where this might be needed.)
2004 if ((ext4_group_first_block_no(sb
, n_group
) +
2005 ext4_group_overhead_blocks(sb
, n_group
) + 2 +
2006 sbi
->s_itb_per_group
+ sbi
->s_cluster_ratio
) >= n_blocks_count
) {
2007 n_blocks_count
= ext4_group_first_block_no(sb
, n_group
);
2009 n_blocks_count_retry
= 0;
2012 resize_inode
= NULL
;
2017 /* extend the last group */
2018 if (n_group
== o_group
)
2019 add
= n_blocks_count
- o_blocks_count
;
2021 add
= EXT4_C2B(sbi
, EXT4_CLUSTERS_PER_GROUP(sb
) - (offset
+ 1));
2023 err
= ext4_group_extend_no_check(sb
, o_blocks_count
, add
);
2028 if (ext4_blocks_count(es
) == n_blocks_count
)
2031 err
= ext4_alloc_flex_bg_array(sb
, n_group
+ 1);
2035 err
= ext4_mb_alloc_groupinfo(sb
, n_group
+ 1);
2039 flex_gd
= alloc_flex_gd(flexbg_size
);
2040 if (flex_gd
== NULL
) {
2045 /* Add flex groups. Note that a regular group is a
2046 * flex group with 1 group.
2048 while (ext4_setup_next_flex_gd(sb
, flex_gd
, n_blocks_count
,
2050 if (jiffies
- last_update_time
> HZ
* 10) {
2051 if (last_update_time
)
2052 ext4_msg(sb
, KERN_INFO
,
2053 "resized to %llu blocks",
2054 ext4_blocks_count(es
));
2055 last_update_time
= jiffies
;
2057 if (ext4_alloc_group_tables(sb
, flex_gd
, flexbg_size
) != 0)
2059 err
= ext4_flex_group_add(sb
, resize_inode
, flex_gd
);
2064 if (!err
&& n_blocks_count_retry
) {
2065 n_blocks_count
= n_blocks_count_retry
;
2066 n_blocks_count_retry
= 0;
2067 free_flex_gd(flex_gd
);
2071 resize_inode
= NULL
;
2078 free_flex_gd(flex_gd
);
2079 if (resize_inode
!= NULL
)
2082 ext4_warning(sb
, "error (%d) occurred during "
2083 "file system resize", err
);
2084 ext4_msg(sb
, KERN_INFO
, "resized filesystem to %llu",
2085 ext4_blocks_count(es
));