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From:   Matthew Wilcox <willy@infradead.org>
To:     linux-fsdevel@vger.kernel.org
Cc:     "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>
Subject: [PATCH v6 30/51] iomap: Inline data shouldn't see THPs
Date:   Wed, 10 Jun 2020 13:13:24 -0700
Message-Id: <20200610201345.13273-31-willy@infradead.org>
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From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

Assert that we're not seeing THPs in functions that read/write
inline data, rather than zeroing out the tail.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/iomap/buffered-io.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 9275268ea97e..318c1ecc18c0 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -215,6 +215,7 @@ iomap_read_inline_data(struct inode *inode, struct page *page,
 		return;
 
 	BUG_ON(page->index);
+	BUG_ON(PageCompound(page));
 	BUG_ON(size > PAGE_SIZE - offset_in_page(iomap->inline_data));
 
 	addr = kmap_atomic(page);
@@ -728,6 +729,7 @@ static size_t iomap_write_end_inline(struct inode *inode, struct page *page,
 	void *addr;
 
 	WARN_ON_ONCE(!PageUptodate(page));
+	BUG_ON(PageCompound(page));
 	BUG_ON(pos + copied > PAGE_SIZE - offset_in_page(iomap->inline_data));
 
 	addr = kmap_atomic(page);
-- 
2.26.2