Set the block size to that specified in on-disk superblock.
Also remove the hard constraint of PAGE_SIZE block size for the
uncompressed device backend. This constraint is temporarily remained
for compressed device and fscache backend, as there is more work needed
to handle the condition where the block size is not equal to PAGE_SIZE.
It is worth noting that the on-disk block size is read prior to
erofs_superblock_csum_verify(), as the read block size is needed in the
latter.
Besides, later we are going to make erofs refer to tar data blobs (which
is 512-byte aligned) for OCI containers, where the block size is 512
bytes. In this case, the 512-byte block size may not be adequate for a
directory to contain enough dirents. To fix this, we are also going to
introduce directory block size independent on the block size.
Due to we have already supported block size smaller than PAGE_SIZE now,
disable all these images with such separated directory block size until
we supported this feature later.
Bug: 303691233
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Yue Hu <huyue2@coolpad.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20230313135309.75269-3-jefflexu@linux.alibaba.com
[ Gao Xiang: update documentation. ]
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
(cherry picked from commit d3c4bdcc756e60b95365c66ff58844ce75d1c8f8)
[dhavale: resolved minor conflict in Documentation/filesystems/erofs.rst]
Signed-off-by: Sandeep Dhavale <dhavale@google.com>
Change-Id: I9a46bfb7ec9f79751e0df8f9d6369192dc861736
3437652fa2