| /* |
| * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README |
| */ |
| |
| /* |
| * Written by Alexander Zarochentcev. |
| * |
| * The kernel part of the (on-line) reiserfs resizer. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/vmalloc.h> |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/reiserfs_fs.h> |
| #include <linux/reiserfs_fs_sb.h> |
| #include <linux/buffer_head.h> |
| |
| int reiserfs_resize (struct super_block * s, unsigned long block_count_new) |
| { |
| int err = 0; |
| struct reiserfs_super_block * sb; |
| struct reiserfs_bitmap_info *bitmap; |
| struct reiserfs_bitmap_info *old_bitmap = SB_AP_BITMAP(s); |
| struct buffer_head * bh; |
| struct reiserfs_transaction_handle th; |
| unsigned int bmap_nr_new, bmap_nr; |
| unsigned int block_r_new, block_r; |
| |
| struct reiserfs_list_bitmap * jb; |
| struct reiserfs_list_bitmap jbitmap[JOURNAL_NUM_BITMAPS]; |
| |
| unsigned long int block_count, free_blocks; |
| int i; |
| int copy_size ; |
| |
| sb = SB_DISK_SUPER_BLOCK(s); |
| |
| if (SB_BLOCK_COUNT(s) >= block_count_new) { |
| printk("can\'t shrink filesystem on-line\n"); |
| return -EINVAL; |
| } |
| |
| /* check the device size */ |
| bh = sb_bread(s, block_count_new - 1); |
| if (!bh) { |
| printk("reiserfs_resize: can\'t read last block\n"); |
| return -EINVAL; |
| } |
| bforget(bh); |
| |
| /* old disk layout detection; those partitions can be mounted, but |
| * cannot be resized */ |
| if (SB_BUFFER_WITH_SB(s)->b_blocknr * SB_BUFFER_WITH_SB(s)->b_size |
| != REISERFS_DISK_OFFSET_IN_BYTES ) { |
| printk("reiserfs_resize: unable to resize a reiserfs without distributed bitmap (fs version < 3.5.12)\n"); |
| return -ENOTSUPP; |
| } |
| |
| /* count used bits in last bitmap block */ |
| block_r = SB_BLOCK_COUNT(s) - |
| (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8; |
| |
| /* count bitmap blocks in new fs */ |
| bmap_nr_new = block_count_new / ( s->s_blocksize * 8 ); |
| block_r_new = block_count_new - bmap_nr_new * s->s_blocksize * 8; |
| if (block_r_new) |
| bmap_nr_new++; |
| else |
| block_r_new = s->s_blocksize * 8; |
| |
| /* save old values */ |
| block_count = SB_BLOCK_COUNT(s); |
| bmap_nr = SB_BMAP_NR(s); |
| |
| /* resizing of reiserfs bitmaps (journal and real), if needed */ |
| if (bmap_nr_new > bmap_nr) { |
| /* reallocate journal bitmaps */ |
| if (reiserfs_allocate_list_bitmaps(s, jbitmap, bmap_nr_new) < 0) { |
| printk("reiserfs_resize: unable to allocate memory for journal bitmaps\n"); |
| unlock_super(s) ; |
| return -ENOMEM ; |
| } |
| /* the new journal bitmaps are zero filled, now we copy in the bitmap |
| ** node pointers from the old journal bitmap structs, and then |
| ** transfer the new data structures into the journal struct. |
| ** |
| ** using the copy_size var below allows this code to work for |
| ** both shrinking and expanding the FS. |
| */ |
| copy_size = bmap_nr_new < bmap_nr ? bmap_nr_new : bmap_nr ; |
| copy_size = copy_size * sizeof(struct reiserfs_list_bitmap_node *) ; |
| for (i = 0 ; i < JOURNAL_NUM_BITMAPS ; i++) { |
| struct reiserfs_bitmap_node **node_tmp ; |
| jb = SB_JOURNAL(s)->j_list_bitmap + i ; |
| memcpy(jbitmap[i].bitmaps, jb->bitmaps, copy_size) ; |
| |
| /* just in case vfree schedules on us, copy the new |
| ** pointer into the journal struct before freeing the |
| ** old one |
| */ |
| node_tmp = jb->bitmaps ; |
| jb->bitmaps = jbitmap[i].bitmaps ; |
| vfree(node_tmp) ; |
| } |
| |
| /* allocate additional bitmap blocks, reallocate array of bitmap |
| * block pointers */ |
| bitmap = vmalloc(sizeof(struct reiserfs_bitmap_info) * bmap_nr_new); |
| if (!bitmap) { |
| /* Journal bitmaps are still supersized, but the memory isn't |
| * leaked, so I guess it's ok */ |
| printk("reiserfs_resize: unable to allocate memory.\n"); |
| return -ENOMEM; |
| } |
| memset (bitmap, 0, sizeof (struct reiserfs_bitmap_info) * SB_BMAP_NR(s)); |
| for (i = 0; i < bmap_nr; i++) |
| bitmap[i] = old_bitmap[i]; |
| |
| /* This doesn't go through the journal, but it doesn't have to. |
| * The changes are still atomic: We're synced up when the journal |
| * transaction begins, and the new bitmaps don't matter if the |
| * transaction fails. */ |
| for (i = bmap_nr; i < bmap_nr_new; i++) { |
| bitmap[i].bh = sb_getblk(s, i * s->s_blocksize * 8); |
| memset(bitmap[i].bh->b_data, 0, sb_blocksize(sb)); |
| reiserfs_test_and_set_le_bit(0, bitmap[i].bh->b_data); |
| |
| set_buffer_uptodate(bitmap[i].bh); |
| mark_buffer_dirty(bitmap[i].bh) ; |
| sync_dirty_buffer(bitmap[i].bh); |
| // update bitmap_info stuff |
| bitmap[i].first_zero_hint=1; |
| bitmap[i].free_count = sb_blocksize(sb) * 8 - 1; |
| } |
| /* free old bitmap blocks array */ |
| SB_AP_BITMAP(s) = bitmap; |
| vfree (old_bitmap); |
| } |
| |
| /* begin transaction, if there was an error, it's fine. Yes, we have |
| * incorrect bitmaps now, but none of it is ever going to touch the |
| * disk anyway. */ |
| err = journal_begin(&th, s, 10); |
| if (err) |
| return err; |
| |
| /* correct last bitmap blocks in old and new disk layout */ |
| reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr - 1].bh, 1); |
| for (i = block_r; i < s->s_blocksize * 8; i++) |
| reiserfs_test_and_clear_le_bit(i, |
| SB_AP_BITMAP(s)[bmap_nr - 1].bh->b_data); |
| SB_AP_BITMAP(s)[bmap_nr - 1].free_count += s->s_blocksize * 8 - block_r; |
| if ( !SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint) |
| SB_AP_BITMAP(s)[bmap_nr - 1].first_zero_hint = block_r; |
| |
| journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr - 1].bh); |
| |
| reiserfs_prepare_for_journal(s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh, 1); |
| for (i = block_r_new; i < s->s_blocksize * 8; i++) |
| reiserfs_test_and_set_le_bit(i, |
| SB_AP_BITMAP(s)[bmap_nr_new - 1].bh->b_data); |
| journal_mark_dirty(&th, s, SB_AP_BITMAP(s)[bmap_nr_new - 1].bh); |
| |
| SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count -= s->s_blocksize * 8 - block_r_new; |
| /* Extreme case where last bitmap is the only valid block in itself. */ |
| if ( !SB_AP_BITMAP(s)[bmap_nr_new - 1].free_count ) |
| SB_AP_BITMAP(s)[bmap_nr_new - 1].first_zero_hint = 0; |
| /* update super */ |
| reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1) ; |
| free_blocks = SB_FREE_BLOCKS(s); |
| PUT_SB_FREE_BLOCKS(s, free_blocks + (block_count_new - block_count - (bmap_nr_new - bmap_nr))); |
| PUT_SB_BLOCK_COUNT(s, block_count_new); |
| PUT_SB_BMAP_NR(s, bmap_nr_new); |
| s->s_dirt = 1; |
| |
| journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s)); |
| |
| SB_JOURNAL(s)->j_must_wait = 1; |
| return journal_end(&th, s, 10); |
| } |