From: Trond Myklebust NFS: Fix issue with EIO on NFS read The problem is that we may be caching writes that would extend the file and create a hole in the region that we are reading. In this case, we need to detect the eof from the server, ensure that we zero out the pages that are part of the hole and mark them as up to date. Signed-off-by: Trond Myklebust --- fs/nfs/read.c | 23 +++++++++++++++-------- 1 files changed, 15 insertions(+), 8 deletions(-) diff --git a/fs/nfs/read.c b/fs/nfs/read.c index 65c0c5b..da9cf11 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c @@ -116,10 +116,17 @@ static void nfs_readpage_truncate_uninit pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; base &= ~PAGE_CACHE_MASK; pglen = PAGE_CACHE_SIZE - base; - if (pglen < remainder) + for (;;) { + if (remainder <= pglen) { + memclear_highpage_flush(*pages, base, remainder); + break; + } memclear_highpage_flush(*pages, base, pglen); - else - memclear_highpage_flush(*pages, base, remainder); + pages++; + remainder -= pglen; + pglen = PAGE_CACHE_SIZE; + base = 0; + } } /* @@ -476,6 +483,8 @@ static void nfs_readpage_set_pages_uptod unsigned int base = data->args.pgbase; struct page **pages; + if (data->res.eof) + count = data->args.count; if (unlikely(count == 0)) return; pages = &data->args.pages[base >> PAGE_CACHE_SHIFT]; @@ -483,11 +492,7 @@ static void nfs_readpage_set_pages_uptod count += base; for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) SetPageUptodate(*pages); - /* - * Was this an eof or a short read? If the latter, don't mark the page - * as uptodate yet. - */ - if (count > 0 && (data->res.eof || data->args.count == data->res.count)) + if (count != 0) SetPageUptodate(*pages); } @@ -502,6 +507,8 @@ static void nfs_readpage_set_pages_error count += base; for (;count >= PAGE_CACHE_SIZE; count -= PAGE_CACHE_SIZE, pages++) SetPageError(*pages); + if (count != 0) + SetPageError(*pages); } /*