f2fs: checkpoint disabling
Note that, it requires "f2fs: return correct errno in f2fs_gc".
This adds a lightweight non-persistent snapshotting scheme to f2fs.
To use, mount with the option checkpoint=disable, and to return to
normal operation, remount with checkpoint=enable. If the filesystem
is shut down before remounting with checkpoint=enable, it will revert
back to its apparent state when it was first mounted with
checkpoint=disable. This is useful for situations where you wish to be
able to roll back the state of the disk in case of some critical
failure.
Signed-off-by: Daniel Rosenberg <drosen@google.com>
[Jaegeuk Kim: use SB_RDONLY instead of MS_RDONLY]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 873f9ea..9ef6f1f 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -537,7 +537,8 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
if (fio->in_list)
goto next;
out:
- if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN))
+ if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) ||
+ f2fs_is_checkpoint_ready(sbi))
__submit_merged_bio(io);
up_write(&io->io_rwsem);
}
@@ -1703,6 +1704,10 @@ static inline bool check_inplace_update_policy(struct inode *inode,
is_inode_flag_set(inode, FI_NEED_IPU))
return true;
+ if (unlikely(fio && is_sbi_flag_set(sbi, SBI_CP_DISABLED) &&
+ !f2fs_is_checkpointed_data(sbi, fio->old_blkaddr)))
+ return true;
+
return false;
}
@@ -1733,6 +1738,9 @@ bool f2fs_should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
return true;
if (IS_ATOMIC_WRITTEN_PAGE(fio->page))
return true;
+ if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED) &&
+ f2fs_is_checkpointed_data(sbi, fio->old_blkaddr)))
+ return true;
}
return false;
}
@@ -2353,6 +2361,10 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
trace_f2fs_write_begin(inode, pos, len, flags);
+ err = f2fs_is_checkpoint_ready(sbi);
+ if (err)
+ goto fail;
+
if ((f2fs_is_atomic_file(inode) &&
!f2fs_available_free_memory(sbi, INMEM_PAGES)) ||
is_inode_flag_set(inode, FI_ATOMIC_REVOKE_REQUEST)) {
