Re: [PATCH 1/6] fs: add a new remove_bdev() super operations callback

[Christoph Hellwig <hch@lst.de>]

On Thu, Jun 26, 2025 at 08:06:03PM +0930, Qu Wenruo wrote:
>
> If I understand the @surprise parameter correctly, it should allow the fs 
> to do read/write as usual if it's not a surprise removal.
>
> And btrfs will take the chance to fully writeback all the dirty pages (more 
> than the default shutdown behavior which only writebacks the current 
> transaction, no dirty data pages.).

That's already taken care of by the call to sync_filesystem in
fs_bdev_mark_dead.

> But in the real world, for test case like generic/730, the @surprise flag 
> is either not properly respected, I'm getting @surprise == false but the 
> block device is already gone.

It only works for drivers that call blk_mark_disk_dead or bdev_mark_dead
directly with the surprise flag.

> So I'm not sure what's the real expected behavior here, and the new flag is 
> only for future expansion for now.

Let's not add just in case arguments.