summaryrefslogtreecommitdiffstats
path: root/fs/reiserfs/resize.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/reiserfs/resize.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/reiserfs/resize.c')
-rw-r--r--fs/reiserfs/resize.c182
1 files changed, 182 insertions, 0 deletions
diff --git a/fs/reiserfs/resize.c b/fs/reiserfs/resize.c
new file mode 100644
index 0000000..1700120
--- /dev/null
+++ b/fs/reiserfs/resize.c
@@ -0,0 +1,182 @@
+/*
+ * 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);
+}
OpenPOWER on IntegriCloud