2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
6 * Written by Alexander Zarochentcev.
8 * The kernel part of the (on-line) reiserfs resizer.
11 #include <linux/kernel.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>
20 int reiserfs_resize (struct super_block * s, unsigned long block_count_new)
22 struct reiserfs_super_block * sb;
23 struct reiserfs_bitmap_info *bitmap;
24 struct buffer_head * bh;
25 struct reiserfs_transaction_handle th;
26 unsigned int bmap_nr_new, bmap_nr;
27 unsigned int block_r_new, block_r;
29 struct reiserfs_list_bitmap * jb;
30 struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS];
32 unsigned long int block_count, free_blocks;
36 sb = SB_DISK_SUPER_BLOCK(s);
38 if (SB_BLOCK_COUNT(s) >= block_count_new) {
39 printk("can\'t shrink filesystem on-line\n");
43 /* check the device size */
44 bh = sb_bread(s, block_count_new - 1);
46 printk("reiserfs_resize: can\'t read last block\n");
51 /* old disk layout detection; those partitions can be mounted, but
52 * cannot be resized */
53 if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size
54 != REISERFS_DISK_OFFSET_IN_BYTES ) {
55 printk("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n");
59 /* count used bits in last bitmap block */
60 block_r = SB_BLOCK_COUNT(s) -
61 (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8;
63 /* count bitmap blocks in new fs */
64 bmap_nr_new = block_count_new / ( s->s_blocksize * 8 );
65 block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8;
69 block_r_new = s->s_blocksize * 8;
72 block_count = SB_BLOCK_COUNT(s);
73 bmap_nr = SB_BMAP_NR(s);
75 /* resizing of reiserfs bitmaps (journal and real), if needed */
76 if (bmap_nr_new > bmap_nr) {
77 /* reallocate journal bitmaps */
78 if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) {
79 printk("reiserfs_resize: unable to allocate memory for journal bitmaps\n");
83 /* the new journal bitmaps are zero filled, now we copy in the bitmap
84 ** node pointers from the old journal bitmap structs, and then
85 ** transfer the new data structures into the journal struct.
87 ** using the copy_size var below allows this code to work for
88 ** both shrinking and expanding the FS.
90 copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr ;
91 copy_size = copy_size * sizeof(struct reiserfs_list_bitmap_node *) ;
92 for (i = 0 ; i < JOURNAL_NUM_BITMAPS ; i++) {
93 struct reiserfs_bitmap_node **node_tmp ;
94 jb = SB_JOURNAL(s)->j_list_bitmap + i ;
95 memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size) ;
97 /* just in case vfree schedules on us, copy the new
98 ** pointer into the journal struct before freeing the
101 node_tmp = jb->bitmaps ;
102 jb->bitmaps = jbitmap[i].bitmaps ;
106 /* allocate additional bitmap blocks, reallocate array of bitmap
108 bitmap = vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
110 printk("reiserfs_resize: unable to allocate memory.\n");
113 memset (bitmap, 0, sizeof (struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
114 for (i = 0; i < bmap_nr; i++)
115 bitmap[i] = SB_AP_BITMAP(s)[i];
116 for (i = bmap_nr; i < bmap_nr_new; i++) {
117 bitmap[i].bh = sb_getblk(s, i * s->s_blocksize * 8);
118 memset(bitmap[i].bh->b_data, 0, sb_blocksize(sb));
119 reiserfs_test_and_set_le_bit(0, bitmap[i].bh->b_data);
121 set_buffer_uptodate(bitmap[i].bh);
122 mark_buffer_dirty(bitmap[i].bh) ;
123 sync_dirty_buffer(bitmap[i].bh);
124 // update bitmap_info stuff
125 bitmap[i].first_zero_hint=1;
126 bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
128 /* free old bitmap blocks array */
129 vfree(SB_AP_BITMAP(s));
130 SB_AP_BITMAP(s) = bitmap;
133 /* begin transaction */
134 journal_begin(&th, s, 10);
136 /* correct last bitmap blocks in old and new disk layout */
137 reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr - 1].bh, 1);
138 for (i = block_r; i < s->s_blocksize * 8; i++)
139 reiserfs_test_and_clear_le_bit(i,
140 SB_AP_BITMAP(s)[bmap_nr - 1].bh->b_data);
141 SB_AP_BITMAP(s)[bmap_nr - 1].free_count += s->s_blocksize * 8 - block_r;
142 if ( !SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint)
143 SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint = block_r;
145 journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr - 1].bh);
147 reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh, 1);
148 for (i = block_r_new; i < s->s_blocksize * 8; i++)
149 reiserfs_test_and_set_le_bit(i,
150 SB_AP_BITMAP(s)[bmap_nr_new - 1].bh->b_data);
151 journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh);
153 SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count -= s->s_blocksize * 8 - block_r_new;
154 /* Extreme case where last bitmap is the only valid block in itself. */
155 if ( !SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count )
156 SB_AP_BITMAP(s)[bmap_nr_new - 1].first_zero_hint = 0;
158 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1) ;
159 free_blocks = SB_FREE_BLOCKS(s);
160 PUT_SB_FREE_BLOCKS(s, free_blocks + (block_count_new - block_count - (bmap_nr_new - bmap_nr)));
161 PUT_SB_BLOCK_COUNT(s, block_count_new);
162 PUT_SB_BMAP_NR(s, bmap_nr_new);
165 journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));
167 SB_JOURNAL(s)->j_must_wait = 1;
168 journal_end(&th, s, 10);