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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -07004
Linus Torvalds1da177e2005-04-16 15:20:36 -07005/*
6 * Written by Alexander Zarochentcev.
7 *
8 * The kernel part of the (on-line) reiserfs resizer.
9 */
10
11#include <linux/kernel.h>
12#include <linux/mm.h>
13#include <linux/vmalloc.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/reiserfs_fs.h>
17#include <linux/reiserfs_fs_sb.h>
18#include <linux/buffer_head.h>
19
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070020int reiserfs_resize(struct super_block *s, unsigned long block_count_new)
Linus Torvalds1da177e2005-04-16 15:20:36 -070021{
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070022 int err = 0;
23 struct reiserfs_super_block *sb;
24 struct reiserfs_bitmap_info *bitmap;
Jeff Mahoney0b3dc172006-09-30 23:28:42 -070025 struct reiserfs_bitmap_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -070026 struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070027 struct buffer_head *bh;
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 struct reiserfs_transaction_handle th;
29 unsigned int bmap_nr_new, bmap_nr;
30 unsigned int block_r_new, block_r;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070031
32 struct reiserfs_list_bitmap *jb;
Linus Torvalds1da177e2005-04-16 15:20:36 -070033 struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070034
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 unsigned long int block_count, free_blocks;
36 int i;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070037 int copy_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39 sb = SB_DISK_SUPER_BLOCK(s);
40
41 if (SB_BLOCK_COUNT(s) >= block_count_new) {
42 printk("can\'t shrink filesystem on-line\n");
43 return -EINVAL;
44 }
45
46 /* check the device size */
47 bh = sb_bread(s, block_count_new - 1);
48 if (!bh) {
49 printk("reiserfs_resize: can\'t read last block\n");
50 return -EINVAL;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070051 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 bforget(bh);
53
54 /* old disk layout detection; those partitions can be mounted, but
55 * cannot be resized */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070056 if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
57 != REISERFS_DISK_OFFSET_IN_BYTES) {
58 printk
59 ("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 return -ENOTSUPP;
61 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070062
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 /* count used bits in last bitmap block */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070064 block_r = SB_BLOCK_COUNT(s) - (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8;
65
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 /* count bitmap blocks in new fs */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070067 bmap_nr_new = block_count_new / (s->s_blocksize * 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070069 if (block_r_new)
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 bmap_nr_new++;
71 else
72 block_r_new = s->s_blocksize * 8;
73
74 /* save old values */
75 block_count = SB_BLOCK_COUNT(s);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070076 bmap_nr = SB_BMAP_NR(s);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78 /* resizing of reiserfs bitmaps (journal and real), if needed */
Linus Torvaldsbd4c6252005-07-12 20:21:28 -070079 if (bmap_nr_new > bmap_nr) {
80 /* reallocate journal bitmaps */
81 if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
82 printk
83 ("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
84 unlock_super(s);
85 return -ENOMEM;
86 }
87 /* the new journal bitmaps are zero filled, now we copy in the bitmap
88 ** node pointers from the old journal bitmap structs, and then
89 ** transfer the new data structures into the journal struct.
90 **
91 ** using the copy_size var below allows this code to work for
92 ** both shrinking and expanding the FS.
93 */
94 copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr;
95 copy_size =
96 copy_size * sizeof(struct reiserfs_list_bitmap_node *);
97 for (i = 0; i < JOURNAL_NUM_BITMAPS; i++) {
98 struct reiserfs_bitmap_node **node_tmp;
99 jb = SB_JOURNAL(s)->j_list_bitmap + i;
100 memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700102 /* just in case vfree schedules on us, copy the new
103 ** pointer into the journal struct before freeing the
104 ** old one
105 */
106 node_tmp = jb->bitmaps;
107 jb->bitmaps = jbitmap[i].bitmaps;
108 vfree(node_tmp);
109 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700111 /* allocate additional bitmap blocks, reallocate array of bitmap
112 * block pointers */
113 bitmap =
114 vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
115 if (!bitmap) {
116 /* Journal bitmaps are still supersized, but the memory isn't
117 * leaked, so I guess it's ok */
118 printk("reiserfs_resize: unable to allocate memory.\n");
119 return -ENOMEM;
120 }
121 memset(bitmap, 0,
122 sizeof(struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
123 for (i = 0; i < bmap_nr; i++)
124 bitmap[i] = old_bitmap[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700126 /* This doesn't go through the journal, but it doesn't have to.
127 * The changes are still atomic: We're synced up when the journal
128 * transaction begins, and the new bitmaps don't matter if the
129 * transaction fails. */
130 for (i = bmap_nr; i < bmap_nr_new; i++) {
Jeff Mahoney50652272006-09-30 23:28:44 -0700131 /* don't use read_bitmap_block since it will cache
132 * the uninitialized bitmap */
133 bh = sb_bread(s, i * s->s_blocksize * 8);
Dmitriy Monakhov2d3466a2007-05-08 00:24:37 -0700134 if (!bh) {
135 vfree(bitmap);
136 return -EIO;
137 }
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700138 memset(bh->b_data, 0, sb_blocksize(sb));
139 reiserfs_test_and_set_le_bit(0, bh->b_data);
Jeff Mahoney6f010462006-09-30 23:28:43 -0700140 reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700141
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700142 set_buffer_uptodate(bh);
143 mark_buffer_dirty(bh);
144 sync_dirty_buffer(bh);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700145 // update bitmap_info stuff
146 bitmap[i].first_zero_hint = 1;
147 bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700148 brelse(bh);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700149 }
150 /* free old bitmap blocks array */
151 SB_AP_BITMAP(s) = bitmap;
152 vfree(old_bitmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 }
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700154
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 /* begin transaction, if there was an error, it's fine. Yes, we have
156 * incorrect bitmaps now, but none of it is ever going to touch the
157 * disk anyway. */
158 err = journal_begin(&th, s, 10);
159 if (err)
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700160 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700162 /* Extend old last bitmap block - new blocks have been made available */
163 info = SB_AP_BITMAP(s) + bmap_nr - 1;
Jeff Mahoney50652272006-09-30 23:28:44 -0700164 bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
165 if (!bh) {
166 int jerr = journal_end(&th, s, 10);
167 if (jerr)
168 return jerr;
169 return -EIO;
170 }
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700171
172 reiserfs_prepare_for_journal(s, bh, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 for (i = block_r; i < s->s_blocksize * 8; i++)
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700174 reiserfs_test_and_clear_le_bit(i, bh->b_data);
175 info->free_count += s->s_blocksize * 8 - block_r;
176 if (!info->first_zero_hint)
177 info->first_zero_hint = block_r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700179 journal_mark_dirty(&th, s, bh);
180 brelse(bh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700182 /* Correct new last bitmap block - It may not be full */
183 info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
Jeff Mahoney50652272006-09-30 23:28:44 -0700184 bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
185 if (!bh) {
186 int jerr = journal_end(&th, s, 10);
187 if (jerr)
188 return jerr;
189 return -EIO;
190 }
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700191
192 reiserfs_prepare_for_journal(s, bh, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 for (i = block_r_new; i < s->s_blocksize * 8; i++)
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700194 reiserfs_test_and_set_le_bit(i, bh->b_data);
195 journal_mark_dirty(&th, s, bh);
196 brelse(bh);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700197
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700198 info->free_count -= s->s_blocksize * 8 - block_r_new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 /* Extreme case where last bitmap is the only valid block in itself. */
Jeff Mahoney0b3dc172006-09-30 23:28:42 -0700200 if (!info->free_count)
201 info->first_zero_hint = 0;
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700202 /* update super */
203 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 free_blocks = SB_FREE_BLOCKS(s);
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700205 PUT_SB_FREE_BLOCKS(s,
206 free_blocks + (block_count_new - block_count -
207 (bmap_nr_new - bmap_nr)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 PUT_SB_BLOCK_COUNT(s, block_count_new);
209 PUT_SB_BMAP_NR(s, bmap_nr_new);
210 s->s_dirt = 1;
211
212 journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
Linus Torvaldsbd4c6252005-07-12 20:21:28 -0700213
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 SB_JOURNAL(s)->j_must_wait = 1;
215 return journal_end(&th, s, 10);
216}