erofs: introduce on-disk lz4 fs configurations
Introduce z_erofs_lz4_cfgs to store all lz4 configurations.
Currently it's only max_distance, but will be used for new
features later.
Link: https://lore.kernel.org/r/20210329012308.28743-4-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c
index 93411e9..97538ff 100644
--- a/fs/erofs/decompressor.c
+++ b/fs/erofs/decompressor.c
@@ -29,9 +29,20 @@ struct z_erofs_decompressor {
};
int z_erofs_load_lz4_config(struct super_block *sb,
- struct erofs_super_block *dsb)
+ struct erofs_super_block *dsb,
+ struct z_erofs_lz4_cfgs *lz4, int size)
{
- u16 distance = le16_to_cpu(dsb->lz4_max_distance);
+ u16 distance;
+
+ if (lz4) {
+ if (size < sizeof(struct z_erofs_lz4_cfgs)) {
+ erofs_err(sb, "invalid lz4 cfgs, size=%u", size);
+ return -EINVAL;
+ }
+ distance = le16_to_cpu(lz4->max_distance);
+ } else {
+ distance = le16_to_cpu(dsb->lz4_max_distance);
+ }
EROFS_SB(sb)->lz4.max_distance_pages = distance ?
DIV_ROUND_UP(distance, PAGE_SIZE) + 1 :