From 3a60f6537c9adf0828bf1dd868c59f659395257e Mon Sep 17 00:00:00 2001 From: David Sterba Date: Wed, 27 Oct 2021 10:39:03 +0200 Subject: [PATCH] Revert "btrfs: compression: drop kmap/kunmap from generic helpers" This reverts commit 4c2bf276b56d8d27ddbafcdf056ef3fc60ae50b0. The kmaps in compression code are still needed and cause crashes on 32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004 with enabled LZO or ZSTD compression. Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839 Signed-off-by: David Sterba --- fs/btrfs/compression.c | 3 ++- fs/btrfs/inode.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 7869ad1..0913ee5 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -172,9 +172,10 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio, /* Hash through the page sector by sector */ for (pg_offset = 0; pg_offset < bytes_left; pg_offset += sectorsize) { - kaddr = page_address(page); + kaddr = kmap_atomic(page); crypto_shash_digest(shash, kaddr + pg_offset, sectorsize, csum); + kunmap_atomic(kaddr); if (memcmp(&csum, cb_sum, csum_size) != 0) { btrfs_print_data_csum_error(inode, disk_start, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 2aa9646..e6772f5 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -287,8 +287,9 @@ static int insert_inline_extent(struct btrfs_trans_handle *trans, cur_size = min_t(unsigned long, compressed_size, PAGE_SIZE); - kaddr = page_address(cpage); + kaddr = kmap_atomic(cpage); write_extent_buffer(leaf, kaddr, ptr, cur_size); + kunmap_atomic(kaddr); i++; ptr += cur_size; -- 2.7.4