Commit 17de39ac authored May 04, 2012 by Josef Bacik Committed by Chris Mason May 04, 2012

Btrfs: fix page leak when allocing extent buffers

If we happen to alloc a extent buffer and then alloc a page and notice that
page is already attached to an extent buffer, we will only unlock it and
free our existing eb. Any pages currently attached to that eb will be
properly freed, but we don't do the page_cache_release() on the page where
we noticed the other extent buffer which can cause us to leak pages and I
hope cause the weird issues we've been seeing in this area. Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

parent e5846fc6

fs/btrfs/extent_io.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -4120,6 +4120,7 @@ struct extent_buffer alloc_extent_buffer(struct extent_io_tree tree,
		if (atomic_inc_not_zero(&exists->refs)) {
		spin_unlock(&mapping->private_lock);
		unlock_page(p);
		page_cache_release(p);
		mark_extent_buffer_accessed(exists);
		goto free_eb;
		}
		@@ -4199,8 +4200,7 @@ free_eb:
		unlock_page(eb->pages[i]);
		}

		if (!atomic_dec_and_test(&eb->refs))
		return exists;
		WARN_ON(!atomic_dec_and_test(&eb->refs));
		btrfs_release_extent_buffer(eb);
		return exists;
		}

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