[PATCH v2 09/13] f2fs: fix data loss during inline tail writing

From: Wu Bo
Date: Tue Sep 10 2024 - 23:45:20 EST


This is detected by xfstest generic/114. The inline data needs to be
read out before writing to avoid losing the already inline data.

Signed-off-by: Wu Bo <bo.wu@xxxxxxxx>
---
fs/f2fs/data.c | 3 ++-
fs/f2fs/file.c | 7 ++++++-
2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 476325a26d4e..275c5739993e 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -3477,7 +3477,8 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
if (inode->i_nlink)
set_page_private_inline(ipage);
goto out;
- }
+ } else if (f2fs_exist_data(inode))
+ f2fs_do_read_inline_data(page_folio(page), ipage);
}

if (!f2fs_lookup_read_extent_cache_block(inode, index,
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 2551403a5b83..64ea0bfc2e1e 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4729,7 +4729,7 @@ static int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *iter,

if (f2fs_has_inline_tail(inode) &&
(pos + count > MAX_INLINE_TAIL(inode))) {
- ret = f2fs_clear_inline_tail(inode, true);
+ ret = f2fs_convert_inline_tail(inode);
if (ret)
return ret;
}
@@ -4842,6 +4842,7 @@ static ssize_t f2fs_dio_write_iter(struct kiocb *iocb, struct iov_iter *from,
if (iocb->ki_flags & IOCB_NOWAIT) {
/* f2fs_convert_inline_inode() and block allocation can block */
if (f2fs_has_inline_data(inode) ||
+ f2fs_has_inline_tail(inode) ||
!f2fs_overwrite_io(inode, pos, count)) {
ret = -EAGAIN;
goto out;
@@ -4861,6 +4862,10 @@ static ssize_t f2fs_dio_write_iter(struct kiocb *iocb, struct iov_iter *from,
if (ret)
goto out;

+ ret = f2fs_convert_inline_tail(inode);
+ if (ret)
+ goto out;
+
f2fs_down_read(&fi->i_gc_rwsem[WRITE]);
if (do_opu)
f2fs_down_read(&fi->i_gc_rwsem[READ]);
--
2.35.3