4.20-stable review patch. If anyone has any objections, please let me know.
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From: Jaegeuk Kim jaegeuk@kernel.org
commit 31867b23d7d1ee3535136c6a410a6cf56f666bfc upstream.
Otherwise, we can get wrong counts incurring checkpoint hang.
IO_W (CP: -24, Data: 24, Flush: ( 0 0 1), Discard: ( 0 0))
Thread A Thread B - f2fs_write_data_pages - __write_data_page - f2fs_submit_page_write - inc_page_count(F2FS_WB_DATA) type is F2FS_WB_DATA due to file is non-atomic one - f2fs_ioc_start_atomic_write - set_inode_flag(FI_ATOMIC_FILE) - f2fs_write_end_io - dec_page_count(F2FS_WB_CP_DATA) type is F2FS_WB_DATA due to file becomes atomic one
Cc: stable@vger.kernel.org Reviewed-by: Chao Yu yuchao0@huawei.com Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/f2fs/file.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
--- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1749,10 +1749,12 @@ static int f2fs_ioc_start_atomic_write(s
down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
- if (!get_dirty_pages(inode)) - goto skip_flush; - - f2fs_msg(F2FS_I_SB(inode)->sb, KERN_WARNING, + /* + * Should wait end_io to count F2FS_WB_CP_DATA correctly by + * f2fs_is_atomic_file. + */ + if (get_dirty_pages(inode)) + f2fs_msg(F2FS_I_SB(inode)->sb, KERN_WARNING, "Unexpected flush for atomic writes: ino=%lu, npages=%u", inode->i_ino, get_dirty_pages(inode)); ret = filemap_write_and_wait_range(inode->i_mapping, 0, LLONG_MAX); @@ -1760,7 +1762,7 @@ static int f2fs_ioc_start_atomic_write(s up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); goto out; } -skip_flush: + set_inode_flag(inode, FI_ATOMIC_FILE); clear_inode_flag(inode, FI_ATOMIC_REVOKE_REQUEST); up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);