Link of compressed pages in zsmalloc

Question

I am trying to understand zsmalloc allocator used in zram and zswap but I am stuck in code of init_zspage in zsmalloc.c

    link = (struct link_free *)kmap_atomic(page) +
                    off / sizeof(*link);

Here link is not initialized. The problem is what will be the value of sizeof(*link) if it not initializes. As far I know sizeof(*link) must be calculated before assignment.

look into http://stackoverflow.com/questions/2731500/using-sizeof-with-a-dynamically-allocated-array — cosinus0, May 20 '15 at 11:11

score 0 · Accepted Answer · answered May 20 '15 at 17:50

This size will be computed at compile time.

struct link_free *link;

235 struct link_free {
236         /* Handle of next free chunk (encodes <PFN, obj_idx>) */
237         void *next;
238 };

i.e. size of this struct = size of pointer. So this is what are youasking about?

Link of compressed pages in zsmalloc

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