On Fri, Jul 21, 2023 at 10:22:21AM +0800, Gao Xiang wrote:
commit 001b8ccd0650727e54ec16ef72bf1b8eeab7168e upstream.
In compact 4B, two adjacent lclusters are packed together as a unit to form on-disk indexes for effective random access, as below:
(amortized = 4, vcnt = 2) _____________________________________________ |___@_____ encoded bits __________|_ blkaddr _| 0 . amortized * vcnt = 8 . . . . amortized * vcnt - 4 = 4 . . .____________________________. |_type (2 bits)_|_clusterofs_|
Therefore, encoded bits for each pack are 32 bits (4 bytes). IOWs, since each lcluster can get 16 bits for its type and clusterofs, the maximum supported lclustersize for compact 4B format is 16k (14 bits).
Fix this to enable compact 4B format for 16k lclusters (blocks), which is tested on an arm64 server with 16k page size.
Fixes: 152a333a5895 ("staging: erofs: add compacted compression indexes support") Link: https://lore.kernel.org/r/20230601112341.56960-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang hsiangkao@linux.alibaba.com
resolve a trivial conflict.
All now queued up.
thanks,
greg k-h