Re: [PATCH v2 2/2] erofs: boost negative xattr lookup with bloom filter

From: Gao Xiang
Date: Wed Jul 05 2023 - 03:55:59 EST




On 2023/7/5 15:44, Alexander Larsson wrote:
On Wed, Jul 5, 2023 at 9:04 AM Jingbo Xu <jefflexu@xxxxxxxxxxxxxxxxx> wrote:

...

+ if (erofs_sb_has_xattr_filter(sbi)) {

As I said in my other mail. I would really like this to just always do
the filter check. It should be safe as older fs:es have zero in place
here, and doing this allows me to create composefs images with the
bloom filters that also work with older kernels.

As my previous email, this flag is on-disk compatible which means old
unsupported kernels will just ignore this and go on mounting.

But this flag indicates a new on-disk feature in the image anyway,
users could know if an image uses the new feature rather than seek to
individual inodes.

Does it sound reasonable or some other consideration?

Thanks,
Gao Xiang