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-rw-r--r--fs/reiserfs/resize.c230
1 files changed, 230 insertions, 0 deletions
diff --git a/fs/reiserfs/resize.c b/fs/reiserfs/resize.c
new file mode 100644
index 0000000000..7b498a0d06
--- /dev/null
+++ b/fs/reiserfs/resize.c
@@ -0,0 +1,230 @@
+/*
+ * 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 "reiserfs.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 *info;
+ 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;
+ int depth;
+
+ 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 */
+ depth = reiserfs_write_unlock_nested(s);
+ bh = sb_bread(s, block_count_new - 1);
+ reiserfs_write_lock_nested(s, depth);
+ 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) -
+ (reiserfs_bmap_count(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 = reiserfs_bmap_count(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");
+ return -ENOMEM;
+ }
+ /*
+ * the new journal bitmaps are zero filled, now we copy i
+ * 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 = min(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 =
+ vzalloc(array_size(bmap_nr_new,
+ sizeof(struct reiserfs_bitmap_info)));
+ 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;
+ }
+ 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++) {
+ int depth;
+ /*
+ * don't use read_bitmap_block since it will cache
+ * the uninitialized bitmap
+ */
+ depth = reiserfs_write_unlock_nested(s);
+ bh = sb_bread(s, i * s->s_blocksize * 8);
+ reiserfs_write_lock_nested(s, depth);
+ if (!bh) {
+ vfree(bitmap);
+ return -EIO;
+ }
+ memset(bh->b_data, 0, sb_blocksize(sb));
+ reiserfs_set_le_bit(0, bh->b_data);
+ reiserfs_cache_bitmap_metadata(s, bh, bitmap + i);
+
+ set_buffer_uptodate(bh);
+ mark_buffer_dirty(bh);
+ depth = reiserfs_write_unlock_nested(s);
+ sync_dirty_buffer(bh);
+ reiserfs_write_lock_nested(s, depth);
+ /* update bitmap_info stuff */
+ bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
+ brelse(bh);
+ }
+ /* 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;
+
+ /* Extend old last bitmap block - new blocks have been made available */
+ info = SB_AP_BITMAP(s) + bmap_nr - 1;
+ bh = reiserfs_read_bitmap_block(s, bmap_nr - 1);
+ if (!bh) {
+ int jerr = journal_end(&th);
+ if (jerr)
+ return jerr;
+ return -EIO;
+ }
+
+ reiserfs_prepare_for_journal(s, bh, 1);
+ for (i = block_r; i < s->s_blocksize * 8; i++)
+ reiserfs_clear_le_bit(i, bh->b_data);
+ info->free_count += s->s_blocksize * 8 - block_r;
+
+ journal_mark_dirty(&th, bh);
+ brelse(bh);
+
+ /* Correct new last bitmap block - It may not be full */
+ info = SB_AP_BITMAP(s) + bmap_nr_new - 1;
+ bh = reiserfs_read_bitmap_block(s, bmap_nr_new - 1);
+ if (!bh) {
+ int jerr = journal_end(&th);
+ if (jerr)
+ return jerr;
+ return -EIO;
+ }
+
+ reiserfs_prepare_for_journal(s, bh, 1);
+ for (i = block_r_new; i < s->s_blocksize * 8; i++)
+ reiserfs_set_le_bit(i, bh->b_data);
+ journal_mark_dirty(&th, bh);
+ brelse(bh);
+
+ info->free_count -= s->s_blocksize * 8 - block_r_new;
+ /* 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_would_wrap(bmap_nr_new) ? : bmap_nr_new);
+
+ journal_mark_dirty(&th, SB_BUFFER_WITH_SB(s));
+
+ SB_JOURNAL(s)->j_must_wait = 1;
+ return journal_end(&th);
+}