goto fail;
case ZSWAP_SWAPCACHE_NEW: /* page is locked */
+ /*
+ * Having a local reference to the zswap entry doesn't exclude
+ * swapping from invalidating and recycling the swap slot. Once
+ * the swapcache is secured against concurrent swapping to and
+ * from the slot, recheck that the entry is still current before
+ * writing.
+ */
+ spin_lock(&tree->lock);
+ if (zswap_rb_search(&tree->rbroot, entry->offset) != entry) {
+ spin_unlock(&tree->lock);
+ delete_from_swap_cache(page_folio(page));
+ ret = -ENOMEM;
+ goto fail;
+ }
+ spin_unlock(&tree->lock);
+
/* decompress */
acomp_ctx = raw_cpu_ptr(entry->pool->acomp_ctx);
dlen = PAGE_SIZE;
goto reject;
}
+ /*
+ * XXX: zswap reclaim does not work with cgroups yet. Without a
+ * cgroup-aware entry LRU, we will push out entries system-wide based on
+ * local cgroup limits.
+ */
objcg = get_obj_cgroup_from_page(page);
- if (objcg && !obj_cgroup_may_zswap(objcg))
- goto shrink;
+ if (objcg && !obj_cgroup_may_zswap(objcg)) {
+ ret = -ENOMEM;
+ goto reject;
+ }
/* reclaim space if needed */
if (zswap_is_full()) {