mm/filemap: drop check for truncated page after I/O
If the I/O completed successfully, the page will remain Uptodate, even if it is subsequently truncated. If the I/O completed with an error, this check would cause us to retry the I/O if the page were truncated before we woke up. There is no need to retry the I/O; the I/O to fill the page failed, so we can legitimately just return -EIO. This code was originally added by commit 56f0d5fe6851 ("[PATCH] readpage-vs-invalidate fix") in 2005 (this commit ID is from the linux-fullhistory tree; it is also commit ba1f08f14b52 in tglx-history). At the time, truncate_complete_page() called ClearPageUptodate(), and so this was fixing a real bug. In 2008, commit 84209e02 ("mm: dont clear PG_uptodate on truncate/invalidate") removed the call to ClearPageUptodate, and this check has been unnecessary ever since. It doesn't do any real harm, but there's no need to keep it. Link: https://lkml.kernel.org/r/20210303222547.1056428-1-willy@infradead.org Signed-off-by:Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by:
William Kucharski <william.kucharski@oracle.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
parent
d31fa86a
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