@@ -5075,6 +5075,18 @@ static void evict_inode_truncate_pages(struct inode *inode)
spin_unlock(&io_tree->lock);
lock_extent_bits(io_tree, start, end, 0, &cached_state);
+
+ /*
+ * If still has DELALLOC flag, the extent didn't reach disk,
+ * and its reserved space won't be freed by delayed_ref.
+ * So we need to free its reserved space here.
+ * (Refer to comment in btrfs_invalidatepage, case 2)
+ *
+ * Note, end is the bytenr of last byte, so we need + 1 here.
+ */
+ if (state->state & EXTENT_DELALLOC)
+ btrfs_qgroup_free_data(inode, start, end - start + 1);
+
clear_extent_bit(io_tree, start, end,
EXTENT_LOCKED | EXTENT_DIRTY |
EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
@@ -8592,6 +8604,18 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
}
}
+ /*
+ * Qgroup reserved space handler
+ * Page here will be either
+ * 1) Already written to disk
+ * In this case, its reserved space is released from data rsv map
+ * and will be freed by delayed_ref handler finally.
+ * So even we call qgroup_free_data(), it won't decrease reserved
+ * space.
+ * 2) Not written to disk
+ * This means the reserved space should be freed here.
+ */
+ btrfs_qgroup_free_data(inode, page_start, PAGE_CACHE_SIZE);
if (!inode_evicting) {
clear_extent_bit(tree, page_start, page_end,
EXTENT_LOCKED | EXTENT_DIRTY |
For btrfs_invalidatepage() and its variant evict_inode_truncate_page(), there will be pages don't reach disk. In that case, their reserved space won't be release nor freed by finish_ordered_io() nor delayed_ref handler. So we must free their qgroup reserved space, or we will leaking reserved space again. So this will patch will call btrfs_qgroup_free_data() for invalidatepage() and its variant evict_inode_truncate_page(). And due to the nature of new btrfs_qgroup_reserve/free_data() reserved space will only be reserved or freed once, so for pages which are already flushed to disk, their reserved space will be released and freed by delayed_ref handler. Double free won't be a problem. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> --- v2: Newly introduced --- fs/btrfs/inode.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)