wc_memory_superblock
sb_entries_offset = offsetof(struct wc_memory_superblock, entries);
if (n_blocks >= ((size_t)-sizeof(struct wc_memory_superblock) /
offset = offsetof(struct wc_memory_superblock, entries[n_blocks]);
struct wc_memory_superblock s;
r = copy_mc_to_kernel(&s, sb(wc), sizeof(struct wc_memory_superblock));
sizeof(struct wc_memory_superblock));
offset += sizeof(struct wc_memory_superblock);
if (offset < sizeof(struct wc_memory_superblock))
static struct wc_memory_superblock *sb(struct dm_writecache *wc)