diff options
| author | Jaegeuk Kim <jaegeuk@kernel.org> | 2017-07-24 19:46:29 -0700 |
|---|---|---|
| committer | Mister Oyster <oysterized@gmail.com> | 2017-10-04 15:22:42 +0200 |
| commit | cb13b28686e7f1b21815e7ba82bec95583a37e30 (patch) | |
| tree | 03ae0c38331be7ae813d6aa5f56907a2993a66b4 /fs/f2fs | |
| parent | 0a74e3cc23f83c9b3a62d1c98879b5b5d69d915f (diff) | |
f2fs: don't give partially written atomic data from process crash
This patch resolves the below scenario.
== Process 1 == == Process 2 ==
open(w) open(rw)
begin
write(new_#1)
process_crash
f_op->flush
locks_remove_posix
f_op>release
read (new_#1)
In order to avoid corrupted database caused by new_#1, we must do roll-back
at process_crash time. In order to check that, this patch keeps task which
triggers transaction begin, and does roll-back in f_op->flush before removing
file locks.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs')
| -rw-r--r-- | fs/f2fs/f2fs.h | 1 | ||||
| -rw-r--r-- | fs/f2fs/file.c | 18 |
2 files changed, 19 insertions, 0 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 6e5e27f1d..06161e5ef 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -640,6 +640,7 @@ struct f2fs_inode_info { struct list_head dirty_list; /* dirty list for dirs and files */ struct list_head gdirty_list; /* linked in global dirty list */ struct list_head inmem_pages; /* inmemory pages managed by f2fs */ + struct task_struct *inmem_task; /* store inmemory task */ struct mutex inmem_lock; /* lock for inmemory pages */ struct extent_tree *extent_tree; /* cached extent_tree entry */ struct rw_semaphore dio_rwsem[2];/* avoid racing between dio and gc */ diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index f5938858e..02526abe0 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1504,6 +1504,22 @@ static int f2fs_release_file(struct inode *inode, struct file *filp) return 0; } +static int f2fs_file_flush(struct file *file, fl_owner_t id) +{ + struct inode *inode = file_inode(file); + + /* + * If the process doing a transaction is crashed, we should do + * roll-back. Otherwise, other reader/write can see corrupted database + * until all the writers close its file. Since this should be done + * before dropping file lock, it needs to do in ->flush. + */ + if (f2fs_is_atomic_file(inode) && + F2FS_I(inode)->inmem_task == current) + drop_inmem_pages(inode); + return 0; +} + #define F2FS_REG_FLMASK (~(FS_DIRSYNC_FL | FS_TOPDIR_FL)) #define F2FS_OTHER_FLMASK (FS_NODUMP_FL | FS_NOATIME_FL) @@ -1623,6 +1639,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp) } inc_stat: + F2FS_I(inode)->inmem_task = current; stat_inc_atomic_write(inode); stat_update_max_atomic_write(inode); out: @@ -2536,6 +2553,7 @@ const struct file_operations f2fs_file_operations = { .open = f2fs_file_open, .release = f2fs_release_file, .mmap = f2fs_file_mmap, + .flush = f2fs_file_flush, .fsync = f2fs_sync_file, .fallocate = f2fs_fallocate, .unlocked_ioctl = f2fs_ioctl, |