[PATCH] f2fs: fix to truncate meta inode pages forcely

From: Chao Yu
Date: Thu Mar 07 2024 - 10:12:45 EST


Below race case can cause data corruption:

Thread A GC thread
- f2fs_inplace_write_data
- gc_data_segment
- ra_data_block
- locked meta_inode page
- invalidate_mapping_pages
: fail to invalidate meta_inode page
due to lock failure or dirty|writeback
status
- f2fs_submit_page_bio
: write last dirty data to old blkaddr
- move_data_block
- load old data from meta_inode page
- f2fs_submit_page_write
: write old data to new blkaddr

Because invalidate_mapping_pages() will skip invalidating page when the
page has unclear status including locked, dirty, writeback and so on, so
we need to use truncate_inode_pages_range() instead of
invalidate_mapping_pages() to make sure meta_inode page will be dropped.

Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC")
Fixes: e3b49ea36802 ("f2fs: invalidate META_MAPPING before IPU/DIO write")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/checkpoint.c | 5 +++--
fs/f2fs/f2fs.h | 28 +++++++++++++++++++++++++++-
fs/f2fs/segment.c | 5 ++---
include/linux/f2fs_fs.h | 1 +
4 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index a09a9609e228..55b7d2cf030f 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -1598,8 +1598,9 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
*/
if (f2fs_sb_has_encrypt(sbi) || f2fs_sb_has_verity(sbi) ||
f2fs_sb_has_compression(sbi))
- invalidate_mapping_pages(META_MAPPING(sbi),
- MAIN_BLKADDR(sbi), MAX_BLKADDR(sbi) - 1);
+ f2fs_bug_on(sbi,
+ invalidate_inode_pages2_range(META_MAPPING(sbi),
+ MAIN_BLKADDR(sbi), MAX_BLKADDR(sbi) - 1));

f2fs_release_ino_entry(sbi, false);

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 4836e7cb0efe..9814e5981a6a 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4655,10 +4655,36 @@ static inline bool f2fs_is_readonly(struct f2fs_sb_info *sbi)
return f2fs_sb_has_readonly(sbi) || f2fs_readonly(sbi->sb);
}

+static inline void f2fs_truncate_meta_inode_pages(struct f2fs_sb_info *sbi,
+ block_t blkaddr, unsigned int cnt)
+{
+ bool need_submit = false;
+ int i = 0;
+
+ do {
+ struct page *page;
+
+ page = find_get_page(META_MAPPING(sbi), blkaddr + i);
+ if (page) {
+ if (PageWriteback(page))
+ need_submit = true;
+ f2fs_put_page(page, 0);
+ }
+ } while (++i < cnt && !need_submit);
+
+ if (need_submit)
+ f2fs_submit_merged_write_cond(sbi, sbi->meta_inode,
+ NULL, 0, DATA);
+
+ truncate_inode_pages_range(META_MAPPING(sbi),
+ F2FS_BLK_TO_BYTES((loff_t)blkaddr),
+ F2FS_BLK_END_BYTES((loff_t)(blkaddr + cnt - 1)));
+}
+
static inline void f2fs_invalidate_internal_cache(struct f2fs_sb_info *sbi,
block_t blkaddr)
{
- invalidate_mapping_pages(META_MAPPING(sbi), blkaddr, blkaddr);
+ f2fs_truncate_meta_inode_pages(sbi, blkaddr, 1);
f2fs_invalidate_compress_page(sbi, blkaddr);
}

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 4ff3b2d14ddf..20af48d7f784 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3741,8 +3741,7 @@ int f2fs_inplace_write_data(struct f2fs_io_info *fio)
}

if (fio->post_read)
- invalidate_mapping_pages(META_MAPPING(sbi),
- fio->new_blkaddr, fio->new_blkaddr);
+ f2fs_truncate_meta_inode_pages(sbi, fio->new_blkaddr, 1);

stat_inc_inplace_blocks(fio->sbi);

@@ -3932,7 +3931,7 @@ void f2fs_wait_on_block_writeback_range(struct inode *inode, block_t blkaddr,
for (i = 0; i < len; i++)
f2fs_wait_on_block_writeback(inode, blkaddr + i);

- invalidate_mapping_pages(META_MAPPING(sbi), blkaddr, blkaddr + len - 1);
+ f2fs_truncate_meta_inode_pages(sbi, blkaddr, len);
}

static int read_compacted_summaries(struct f2fs_sb_info *sbi)
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index 755e9a41b196..a357287eac1e 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -27,6 +27,7 @@

#define F2FS_BYTES_TO_BLK(bytes) ((bytes) >> F2FS_BLKSIZE_BITS)
#define F2FS_BLK_TO_BYTES(blk) ((blk) << F2FS_BLKSIZE_BITS)
+#define F2FS_BLK_END_BYTES(blk) (F2FS_BLK_TO_BYTES(blk + 1) - 1)

/* 0, 1(node nid), 2(meta nid) are reserved node id */
#define F2FS_RESERVED_NODE_NUM 3
--
2.40.1