2 files changed, 16 insertions, 10 deletions

diff --git a/drivers/md/dm-pcache/cache.c b/drivers/md/dm-pcache/cache.c
index 698697a7a73c..534bf07b794f 100644
--- a/drivers/md/dm-pcache/cache.c
+++ b/drivers/md/dm-pcache/cache.c
@@ -10,7 +10,8 @@ struct kmem_cache *key_cache;
 
 static inline struct pcache_cache_info *get_cache_info_addr(struct pcache_cache *cache)
 {
-	return cache->cache_info_addr + cache->info_index;
+	return (struct pcache_cache_info *)((char *)cache->cache_info_addr +
+						(size_t)cache->info_index * PCACHE_CACHE_INFO_SIZE);
 }
 
 static void cache_info_write(struct pcache_cache *cache)
@@ -21,10 +22,10 @@ static void cache_info_write(struct pcache_cache *cache)
 	cache_info->header.crc = pcache_meta_crc(&cache_info->header,
 						sizeof(struct pcache_cache_info));
 
+	cache->info_index = (cache->info_index + 1) % PCACHE_META_INDEX_MAX;
 	memcpy_flushcache(get_cache_info_addr(cache), cache_info,
 			sizeof(struct pcache_cache_info));
-
-	cache->info_index = (cache->info_index + 1) % PCACHE_META_INDEX_MAX;
+	pmem_wmb();
 }
 
 static void cache_info_init_default(struct pcache_cache *cache);
@@ -49,6 +50,8 @@ static int cache_info_init(struct pcache_cache *cache, struct pcache_cache_optio
 			return -EINVAL;
 		}
 
+		cache->info_index = ((char *)cache_info_addr - (char *)cache->cache_info_addr) / PCACHE_CACHE_INFO_SIZE;
+
 		return 0;
 	}
 
@@ -93,10 +96,10 @@ void cache_pos_encode(struct pcache_cache *cache,
 	pos_onmedia.header.seq = seq;
 	pos_onmedia.header.crc = cache_pos_onmedia_crc(&pos_onmedia);
 
+	*index = (*index + 1) % PCACHE_META_INDEX_MAX;
+
 	memcpy_flushcache(pos_onmedia_addr, &pos_onmedia, sizeof(struct pcache_cache_pos_onmedia));
 	pmem_wmb();
-
-	*index = (*index + 1) % PCACHE_META_INDEX_MAX;
 }
 
 int cache_pos_decode(struct pcache_cache *cache,
diff --git a/drivers/md/dm-pcache/cache_segment.c b/drivers/md/dm-pcache/cache_segment.c
index f0b58980806e..9d92e2b067ed 100644
--- a/drivers/md/dm-pcache/cache_segment.c
+++ b/drivers/md/dm-pcache/cache_segment.c
@@ -26,11 +26,11 @@ static void cache_seg_info_write(struct pcache_cache_segment *cache_seg)
 	seg_info->header.seq++;
 	seg_info->header.crc = pcache_meta_crc(&seg_info->header, sizeof(struct pcache_segment_info));
 
+	cache_seg->info_index = (cache_seg->info_index + 1) % PCACHE_META_INDEX_MAX;
+
 	seg_info_addr = get_seg_info_addr(cache_seg);
 	memcpy_flushcache(seg_info_addr, seg_info, sizeof(struct pcache_segment_info));
 	pmem_wmb();
-
-	cache_seg->info_index = (cache_seg->info_index + 1) % PCACHE_META_INDEX_MAX;
 	mutex_unlock(&cache_seg->info_lock);
 }
 
@@ -56,7 +56,10 @@ static int cache_seg_info_load(struct pcache_cache_segment *cache_seg)
 		ret = -EIO;
 		goto out;
 	}
-	cache_seg->info_index = cache_seg_info_addr - cache_seg_info_addr_base;
+
+	cache_seg->info_index =
+		((char *)cache_seg_info_addr - (char *)cache_seg_info_addr_base) /
+		PCACHE_SEG_INFO_SIZE;
 out:
 	mutex_unlock(&cache_seg->info_lock);
 
@@ -129,10 +132,10 @@ static void cache_seg_ctrl_write(struct pcache_cache_segment *cache_seg)
 	cache_seg_gen.header.crc = pcache_meta_crc(&cache_seg_gen.header,
 						 sizeof(struct pcache_cache_seg_gen));
 
+	cache_seg->gen_index = (cache_seg->gen_index + 1) % PCACHE_META_INDEX_MAX;
+
 	memcpy_flushcache(get_cache_seg_gen_addr(cache_seg), &cache_seg_gen, sizeof(struct pcache_cache_seg_gen));
 	pmem_wmb();
-
-	cache_seg->gen_index = (cache_seg->gen_index + 1) % PCACHE_META_INDEX_MAX;
 }
 
 static void cache_seg_ctrl_init(struct pcache_cache_segment *cache_seg)