From 1c350a597c2d617291d353ac40f505b396ac8365 Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Fri, 8 Jul 2022 18:10:01 +0800 Subject: [PATCH] erofs: avoid consecutive detection for Highmem memory [ Upstream commit 448b5a1548d87c246c3d0c3df8480d3c6eb6c11a ] Currently, vmap()s are avoided if physical addresses are consecutive for decompressed buffers. I observed that is very common for 4KiB pclusters since the numbers of decompressed pages are almost 2 or 3. However, such detection doesn't work for Highmem pages on 32-bit machines, let's fix it now. Reported-by: Liu Jinbao Fixes: 7fc45dbc938a ("staging: erofs: introduce generic decompression backend") Link: https://lore.kernel.org/r/20220708101001.21242-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang Signed-off-by: Sasha Levin --- fs/erofs/decompressor.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index ad3f313..8193c14 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -93,14 +93,18 @@ static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, if (page) { __clear_bit(j, bounced); - if (kaddr) { - if (kaddr + PAGE_SIZE == page_address(page)) + if (!PageHighMem(page)) { + if (!i) { + kaddr = page_address(page); + continue; + } + if (kaddr && + kaddr + PAGE_SIZE == page_address(page)) { kaddr += PAGE_SIZE; - else - kaddr = NULL; - } else if (!i) { - kaddr = page_address(page); + continue; + } } + kaddr = NULL; continue; } kaddr = NULL; -- 2.7.4