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From:   "Matthew Wilcox (Oracle)" <willy@infradead.org>
To:     linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Cc:     "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        "Darrick J . Wong" <darrick.wong@oracle.com>,
        linux-block@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>
Subject: [PATCH 10/11] iomap: Inline data shouldn't see THPs
Date:   Mon, 24 Aug 2020 16:16:59 +0100
Message-Id: <20200824151700.16097-11-willy@infradead.org>
In-Reply-To: <20200824151700.16097-1-willy@infradead.org>
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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 52d371c59758..ca2aa1995519 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -210,6 +210,7 @@ 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);
@@ -727,6 +728,7 @@ static size_t iomap_write_end_inline(struct inode *inode, struct page *page,
 
 	flush_dcache_page(page);
 	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);
-- 
2.28.0