6.1-stable review patch. If anyone has any objections, please let me know.
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From: Qu Wenruo wqu@suse.com
commit 5e0e879926c1ce7e1f5e0dfaacaf2d105f7d8a05 upstream.
[BUG] After commit 72a69cd03082 ("btrfs: subpage: pack all subpage bitmaps into a larger bitmap"), the DEBUG section of btree_dirty_folio() would no longer compile.
[CAUSE] If DEBUG is defined, we would do extra checks for btree_dirty_folio(), mostly to make sure the range we marked dirty has an extent buffer and that extent buffer is dirty.
For subpage, we need to iterate through all the extent buffers covered by that page range, and make sure they all matches the criteria.
However commit 72a69cd03082 ("btrfs: subpage: pack all subpage bitmaps into a larger bitmap") changes how we store the bitmap, we pack all the 16 bits bitmaps into a larger bitmap, which would save some space.
This means we no longer have btrfs_subpage::dirty_bitmap, instead the dirty bitmap is starting at btrfs_subpage_info::dirty_offset, and has a length of btrfs_subpage_info::bitmap_nr_bits.
[FIX] Although I'm not sure if it still makes sense to maintain such code, at least let it compile.
This patch would let us test the bits one by one through the bitmaps.
CC: stable@vger.kernel.org # 6.1+ Signed-off-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/disk-io.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
--- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -859,6 +859,7 @@ static bool btree_dirty_folio(struct add struct folio *folio) { struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb); + struct btrfs_subpage_info *spi = fs_info->subpage_info; struct btrfs_subpage *subpage; struct extent_buffer *eb; int cur_bit = 0; @@ -872,18 +873,19 @@ static bool btree_dirty_folio(struct add btrfs_assert_tree_write_locked(eb); return filemap_dirty_folio(mapping, folio); } + + ASSERT(spi); subpage = folio_get_private(folio);
- ASSERT(subpage->dirty_bitmap); - while (cur_bit < BTRFS_SUBPAGE_BITMAP_SIZE) { + for (cur_bit = spi->dirty_offset; + cur_bit < spi->dirty_offset + spi->bitmap_nr_bits; + cur_bit++) { unsigned long flags; u64 cur; - u16 tmp = (1 << cur_bit);
spin_lock_irqsave(&subpage->lock, flags); - if (!(tmp & subpage->dirty_bitmap)) { + if (!test_bit(cur_bit, subpage->bitmaps)) { spin_unlock_irqrestore(&subpage->lock, flags); - cur_bit++; continue; } spin_unlock_irqrestore(&subpage->lock, flags); @@ -896,7 +898,7 @@ static bool btree_dirty_folio(struct add btrfs_assert_tree_write_locked(eb); free_extent_buffer(eb);
- cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits); + cur_bit += (fs_info->nodesize >> fs_info->sectorsize_bits) - 1; } return filemap_dirty_folio(mapping, folio); }