@@ -503,15 +529,13 @@ static void tmem_pampd_destroy_all_in_ob
  * always flushes for simplicity.
  */
 int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
-		struct page *page)
+		char *data, size_t size, bool raw, int ephemeral)

 {
 	struct tmem_obj *obj = NULL, *objfound = NULL, *objnew = NULL;
 	void *pampd = NULL, *pampd_del = NULL;
 	int ret = -ENOMEM;
-	bool ephemeral;
 	struct tmem_hashbucket *hb;
 
-	ephemeral = is_ephemeral(pool);
 	hb = &pool->hashbucket[tmem_oid_hash(oidp)];
 	spin_lock(&hb->lock);
 	obj = objfound = tmem_obj_find(hb, oidp);

@@ -521,7 +545,7 @@ int tmem_put(struct tmem_pool *pool, str
 			/* if found, is a dup put, flush the old one */
 			pampd_del = tmem_pampd_delete_from_obj(obj, index);
 			BUG_ON(pampd_del != pampd);
-			(*tmem_pamops.free)(pampd, pool);
+			(*tmem_pamops.free)(pampd, pool, oidp, index);
 			if (obj->pampd_count == 0) {
 				objnew = obj;
 				objfound = NULL;

@@ -538,7 +562,8 @@ int tmem_put(struct tmem_pool *pool, str
 	}
 	BUG_ON(obj == NULL);
 	BUG_ON(((objnew != obj) && (objfound != obj)) || (objnew == objfound));
-	pampd = (*tmem_pamops.create)(obj->pool, &obj->oid, index, page);
+	pampd = (*tmem_pamops.create)(data, size, raw, ephemeral,
+					obj->pool, &obj->oid, index);
 	if (unlikely(pampd == NULL))
 		goto free;
 	ret = tmem_pampd_add_to_obj(obj, index, pampd);

@@ -551,7 +576,7 @@ delete_and_free:
 	(void)tmem_pampd_delete_from_obj(obj, index);
 free:
 	if (pampd)
-		(*tmem_pamops.free)(pampd, pool);
+		(*tmem_pamops.free)(pampd, pool, NULL, 0);
 	if (objnew) {
 		tmem_obj_free(objnew, hb);
 		(*tmem_hostops.obj_free)(objnew, pool);

@@ -573,41 +598,52 @@ out:
  * "put" done with the same handle).
 
  */
-int tmem_get(struct tmem_pool *pool, struct tmem_oid *oidp,
-				uint32_t index, struct page *page)
+int tmem_get(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
+		char *data, size_t *size, bool raw, int get_and_free)

+		spin_unlock(&hb->lock);
+	}
+	if (free)
+		ret = (*tmem_pamops.get_data_and_free)(
+				data, size, raw, pampd, pool, oidp, index);
+	else
+		ret = (*tmem_pamops.get_data)(
+				data, size, raw, pampd, pool, oidp, index);
+	if (ret < 0)
+		goto out;
 	ret = 0;
 out:
-	spin_unlock(&hb->lock);
+	if (lock_held)
+		spin_unlock(&hb->lock);
 	return ret;
 }
 

@@ -632,7 +668,7 @@ int tmem_flush_page(struct tmem_pool *po
 	pampd = tmem_pampd_delete_from_obj(obj, index);
 	if (pampd == NULL)
 		goto out;
-	(*tmem_pamops.free)(pampd, pool);
+	(*tmem_pamops.free)(pampd, pool, oidp, index);
 	if (obj->pampd_count == 0) {
 		tmem_obj_free(obj, hb);
 		(*tmem_hostops.obj_free)(obj, pool);

@@ -645,6 +681,30 @@ out:
 }
 
 /*
+ * If a page in tmem matches the handle, replace the page so that any
+ * subsequent "get" gets the new page.  Returns the new page if
+ * there was a page to replace, else returns NULL.

+ */
+int tmem_replace(struct tmem_pool *pool, struct tmem_oid *oidp,
+			uint32_t index, void *new_pampd)
+{
+	struct tmem_obj *obj;
+	int ret = -1;
+	struct tmem_hashbucket *hb;
+
+	hb = &pool->hashbucket[tmem_oid_hash(oidp)];
+	spin_lock(&hb->lock);
+	obj = tmem_obj_find(hb, oidp);
+	if (obj == NULL)
+		goto out;
+	new_pampd = tmem_pampd_replace_in_obj(obj, index, new_pampd);
+	ret = (*tmem_pamops.replace_in_obj)(new_pampd, obj);
+out:
+	spin_unlock(&hb->lock);
+	return ret;
+}
+
+/*
  * "Flush" all pages in tmem matching this oid.
  */
 int tmem_flush_object(struct tmem_pool *pool, struct tmem_oid *oidp)
diff -Napur -X linux-3.0-rc1/Documentation/dontdiff linux-3.0-rc4/drivers/staging/zcache/tmem.h linux-3.0-rc4-zcache/drivers/staging/zcache/tmem.h

--- linux-3.0-rc4/drivers/staging/zcache/tmem.h	2011-06-20 21:25:46.000000000 -0600
+++ linux-3.0-rc4-zcache/drivers/staging/zcache/tmem.h	2011-06-25 15:43:20.236906477 -0600

@@ -147,6 +147,7 @@ struct tmem_obj {
 	unsigned int objnode_tree_height;
 	unsigned long objnode_count;
 	long pampd_count;
+	void *extra; /* for private use by pampd implementation */
 	DECL_SENTINEL
 };
 

@@ -166,10 +167,18 @@ struct tmem_objnode {
 
 /* pampd abstract datatype methods provided by the PAM implementation */
 struct tmem_pamops {
-	void *(*create)(struct tmem_pool *, struct tmem_oid *, uint32_t,
-			struct page *);
-	int (*get_data)(struct page *, void *, struct tmem_pool *);
-	void (*free)(void *, struct tmem_pool *);
+	void *(*create)(char *, size_t, bool, int,
+			struct tmem_pool *, struct tmem_oid *, uint32_t);
+	int (*get_data)(char *, size_t *, bool, void *, struct tmem_pool *,
+				struct tmem_oid *, uint32_t);
+	int (*get_data_and_free)(char *, size_t *, bool, void *,
+				struct tmem_pool *, struct tmem_oid *,
+				uint32_t);
+	void (*free)(void *, struct tmem_pool *, struct tmem_oid *, uint32_t);
+	void (*free_obj)(struct tmem_pool *, struct tmem_obj *);
+	bool (*is_remote)(void *);
+	void (*new_obj)(struct tmem_obj *);
+	int (*replace_in_obj)(void *, struct tmem_obj *);
 };
 extern void tmem_register_pamops(struct tmem_pamops *m);
 

@@ -184,9 +193,11 @@ extern void tmem_register_hostops(struct
 
 /* core tmem accessor functions */
 extern int tmem_put(struct tmem_pool *, struct tmem_oid *, uint32_t index,
-			struct page *page);
+			char *, size_t, bool, int);
 extern int tmem_get(struct tmem_pool *, struct tmem_oid *, uint32_t index,
-			struct page *page);
+			char *, size_t *, bool, int);
+extern int tmem_replace(struct tmem_pool *, struct tmem_oid *, uint32_t index,
+			void *);
 extern int tmem_flush_page(struct tmem_pool *, struct tmem_oid *,
 			uint32_t index);
 extern int tmem_flush_object(struct tmem_pool *, struct tmem_oid *);

diff -Napur -X linux-3.0-rc1/Documentation/dontdiff linux-3.0-rc4/drivers/staging/zcache/zcache.c linux-3.0-rc4-zcache/drivers/staging/zcache/zcache.c

--- linux-3.0-rc4/drivers/staging/zcache/zcache.c	2011-06-20 21:25:46.000000000 -0600
+++ linux-3.0-rc4-zcache/drivers/staging/zcache/zcache.c	2011-06-25 15:45:55.016705466 -0600

@@ -49,6 +49,32 @@
 	(__GFP_FS | __GFP_NORETRY | __GFP_NOWARN | __GFP_NOMEMALLOC)
 #endif
 
+#define MAX_POOLS_PER_CLIENT 16
+
+#define MAX_CLIENTS 16
+#define LOCAL_CLIENT ((uint16_t)-1)
+struct zcache_client {
+	struct tmem_pool *tmem_pools[MAX_POOLS_PER_CLIENT];
+	struct xv_pool *xvpool;
+	bool allocated;
+	atomic_t refcount;
+};
+
+static struct zcache_client zcache_host;
+static struct zcache_client zcache_clients[MAX_CLIENTS];
+
+static inline uint16_t get_client_id_from_client(struct zcache_client *cli)
+{
+	if (cli == &zcache_host)
+		return LOCAL_CLIENT;

+	return cli - &zcache_clients[0];
+}
+
+static inline bool is_local_client(struct zcache_client *cli)
+{
+	return cli == &zcache_host;
+}
+
 /**********
  * Compression buddies ("zbud") provides for packing two (or, possibly
  * in the future, more) compressed ephemeral pages into a single "raw"

@@ -72,7 +98,8 @@
 #define ZBUD_MAX_BUDS 2
 
 struct zbud_hdr {
-	uint32_t pool_id;
+	uint16_t client_id;
+	uint16_t pool_id;
 	struct tmem_oid oid;
 	uint32_t index;
 	uint16_t size; /* compressed size in bytes, zero means unused */

@@ -294,7 +321,8 @@ static void zbud_free_and_delist(struct 
 	}
 }
 
-static struct zbud_hdr *zbud_create(uint32_t pool_id, struct tmem_oid *oid,
+static struct zbud_hdr *zbud_create(uint16_t client_id, uint16_t pool_id,
+					struct tmem_oid *oid,
 					uint32_t index, struct page *page,
 					void *cdata, unsigned size)
 {

@@ -353,6 +381,7 @@ init_zh:
 	zh->index = index;
 	zh->oid = *oid;
 	zh->pool_id = pool_id;
+	zh->client_id = client_id;
 	/* can wait to copy the data until the list locks are dropped */
 	spin_unlock(&zbud_budlists_spinlock);
 

@@ -407,7 +436,8 @@ static unsigned long zcache_evicted_raw_
 static unsigned long zcache_evicted_buddied_pages;
 static unsigned long zcache_evicted_unbuddied_pages;
 
-static struct tmem_pool *zcache_get_pool_by_id(uint32_t poolid);
+static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id,
+						uint16_t poolid);
 static void zcache_put_pool(struct tmem_pool *pool);
 
 /*

@@ -417,7 +447,8 @@ static void zbud_evict_zbpg(struct zbud_
 {
 	struct zbud_hdr *zh;
 	int i, j;
-	uint32_t pool_id[ZBUD_MAX_BUDS], index[ZBUD_MAX_BUDS];
+	uint32_t pool_id[ZBUD_MAX_BUDS], client_id[ZBUD_MAX_BUDS];
+	uint32_t index[ZBUD_MAX_BUDS];
 	struct tmem_oid oid[ZBUD_MAX_BUDS];
 	struct tmem_pool *pool;
 

@@ -426,6 +457,7 @@ static void zbud_evict_zbpg(struct zbud_
 	for (i = 0, j = 0; i < ZBUD_MAX_BUDS; i++) {
 		zh = &zbpg->buddy[i];
 		if (zh->size) {
+			client_id[j] = zh->client_id;
 			pool_id[j] = zh->pool_id;
 			oid[j] = zh->oid;
 			index[j] = zh->index;

@@ -435,7 +467,7 @@ static void zbud_evict_zbpg(struct zbud_
 	}
 	spin_unlock(&zbpg->lock);
 	for (i = 0; i < j; i++) {
-		pool = zcache_get_pool_by_id(pool_id[i]);
+		pool = zcache_get_pool_by_id(client_id[i], pool_id[i]);
 		if (pool != NULL) {
 			tmem_flush_page(pool, &oid[i], index[i]);
 			zcache_put_pool(pool);

@@ -677,36 +709,70 @@ static unsigned long zcache_flobj_found;
 static unsigned long zcache_failed_eph_puts;
 static unsigned long zcache_failed_pers_puts;
 
-#define MAX_POOLS_PER_CLIENT 16
-
-static struct {
-	struct tmem_pool *tmem_pools[MAX_POOLS_PER_CLIENT];
-	struct xv_pool *xvpool;
-} zcache_client;
-
 /*
  * Tmem operations assume the poolid implies the invoking client.
- * Zcache only has one client (the kernel itself), so translate
- * the poolid into the tmem_pool allocated for it.  A KVM version
+ * Zcache only has one client (the kernel itself): LOCAL_CLIENT.
+ * RAMster has each client numbered by cluster node, and a KVM version
  * of zcache would have one client per guest and each client might
  * have a poolid==N.
  */
-static struct tmem_pool *zcache_get_pool_by_id(uint32_t poolid)
+static struct tmem_pool *zcache_get_pool_by_id(uint16_t cli_id, uint16_t poolid)
 {
 	struct tmem_pool *pool = NULL;
+	struct zcache_client *cli = NULL;
 
-	if (poolid >= 0) {
-		pool = zcache_client.tmem_pools[poolid];
+	if (cli_id == LOCAL_CLIENT)
+		cli = &zcache_host;
+	else {
+		if (cli_id >= MAX_CLIENTS)
+			goto out;
+		cli = &zcache_clients[cli_id];
+		if (cli == NULL)
+			goto out;
+		atomic_inc(&cli->refcount);
+	}
+	if (poolid < MAX_POOLS_PER_CLIENT) {
+		pool = cli->tmem_pools[poolid];
 		if (pool != NULL)
 			atomic_inc(&pool->refcount);
 	}
+out:
 	return pool;
 }
 
 static void zcache_put_pool(struct tmem_pool *pool)
 {
-	if (pool != NULL)
-		atomic_dec(&pool->refcount);
+	struct zcache_client *cli = NULL;
+
+	if (pool == NULL)
+		BUG();
+	cli = pool->client;
+	atomic_dec(&pool->refcount);
+	atomic_dec(&cli->refcount);
+}
+
+int zcache_new_client(uint16_t cli_id)
+{
+	struct zcache_client *cli = NULL;
+	int ret = -1;
+
+	if (cli_id == LOCAL_CLIENT)
+		cli = &zcache_host;
+	else if ((unsigned int)cli_id < MAX_CLIENTS)
+		cli = &zcache_clients[cli_id];
+	if (cli == NULL)
+		goto out;
+	if (cli->allocated)
+		goto out;
+	cli->allocated = 1;
+#ifdef CONFIG_FRONTSWAP
+	cli->xvpool = xv_create_pool();
+	if (cli->xvpool == NULL)
+		goto out;
+#endif
+	ret = 0;
+out:
+	return ret;
 }
 
 /* counters for debugging */

@@ -901,26 +967,28 @@ static unsigned long zcache_curr_pers_pa
 /* forward reference */
 static int zcache_compress(struct page *from, void **out_va, size_t *out_len);
 
-static void *zcache_pampd_create(struct tmem_pool *pool, struct tmem_oid *oid,
-				 uint32_t index, struct page *page)
+static void *zcache_pampd_create(char *data, size_t size, bool raw, int eph,
+				struct tmem_pool *pool, struct tmem_oid *oid,
+				 uint32_t index)
 {
 	void *pampd = NULL, *cdata;
 	size_t clen;
 	int ret;
-	bool ephemeral = is_ephemeral(pool);
 	unsigned long count;
+	struct page *page = virt_to_page(data);
+	struct zcache_client *cli = pool->client;
+	uint16_t client_id = get_client_id_from_client(cli);
 
-	if (ephemeral) {
+	if (eph) {
 		ret = zcache_compress(page, &cdata, &clen);
 		if (ret == 0)
-
 			goto out;
 		if (clen == 0 || clen > zbud_max_buddy_size()) {
 			zcache_compress_poor++;
 			goto out;
 		}
-		pampd = (void *)zbud_create(pool->pool_id, oid, index,
-						page, cdata, clen);
+		pampd = (void *)zbud_create(client_id, pool->pool_id, oid,
+						index, page, cdata, clen);
 		if (pampd != NULL) {
 			count = atomic_inc_return(&zcache_curr_eph_pampd_count);
 			if (count > zcache_curr_eph_pampd_count_max)

@@ -942,7 +1010,7 @@ static void *zcache_pampd_create(struct 
 			zcache_compress_poor++;
 			goto out;
 		}
-		pampd = (void *)zv_create(zcache_client.xvpool, pool->pool_id,
+		pampd = (void *)zv_create(cli->xvpool, pool->pool_id,
 						oid, index, cdata, clen);
 		if (pampd == NULL)
 			goto out;

@@ -958,15 +1026,31 @@ out:
  * fill the pageframe corresponding to the struct page with the data
  * from the passed pampd
  */
-static int zcache_pampd_get_data(struct page *page, void *pampd,
-						struct tmem_pool *pool)
+static int zcache_pampd_get_data(char *data, size_t *bufsize, bool raw,
+					void *pampd, struct tmem_pool *pool,
+					struct tmem_oid *oid, uint32_t index)
 {
 	int ret = 0;
 
-	if (is_ephemeral(pool))
-		ret = zbud_decompress(page, pampd);
-	else
-		zv_decompress(page, pampd);
+	BUG_ON(is_ephemeral(pool));
+	zv_decompress(virt_to_page(data), pampd);
+	return ret;
+}
+
+/*
+ * fill the pageframe corresponding to the struct page with the data
+ * from the passed pampd
+ */
+static int zcache_pampd_get_data_and_free(char *data, size_t *bufsize, bool raw,
+					void *pampd, struct tmem_pool *pool,
+					struct tmem_oid *oid, uint32_t index)
+{
+	int ret = 0;
+
+	BUG_ON(!is_ephemeral(pool));
+	zbud_decompress(virt_to_page(data), pampd);
+	zbud_free_and_delist((struct zbud_hdr *)pampd);
+	atomic_dec(&zcache_curr_eph_pampd_count);
 	return ret;
 }
 

@@ -974,23 +1058,49 @@ static int zcache_pampd_get_data(struct 
  * free the pampd and remove it from any zcache lists
  * pampd must no longer be pointed to from any tmem data structures!
  */
-static void zcache_pampd_free(void *pampd, struct tmem_pool *pool)
+static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
+				struct tmem_oid *oid, uint32_t index)
 {
+	struct zcache_client *cli = pool->client;
+
 	if (is_ephemeral(pool)) {
 		zbud_free_and_delist((struct zbud_hdr *)pampd);
 		atomic_dec(&zcache_curr_eph_pampd_count);
 		BUG_ON(atomic_read(&zcache_curr_eph_pampd_count) < 0);
 	} else {
-		zv_free(zcache_client.xvpool, (struct zv_hdr *)pampd);
+		zv_free(cli->xvpool, (struct zv_hdr *)pampd);
 		atomic_dec(&zcache_curr_pers_pampd_count);
 		BUG_ON(atomic_read(&zcache_curr_pers_pampd_count) < 0);
 	}
 }
 
+static void zcache_pampd_free_obj(struct tmem_pool *pool, struct tmem_obj *obj)
+{
+}
+
+static void zcache_pampd_new_obj(struct tmem_obj *obj)
+{
+}
+
+static int zcache_pampd_replace_in_obj(void *pampd, struct tmem_obj *obj)
+{
+	return -1;
+}
+
+static bool zcache_pampd_is_remote(void *pampd)
+{
+	return 0;
+}
+
 static struct tmem_pamops zcache_pamops = {
 	.create = zcache_pampd_create,
 	.get_data = zcache_pampd_get_data,
+	.get_data_and_free = zcache_pampd_get_data_and_free,
 	.free = zcache_pampd_free,
+	.free_obj = zcache_pampd_free_obj,
+	.new_obj = zcache_pampd_new_obj,
+	.replace_in_obj = zcache_pampd_replace_in_obj,
+	.is_remote = zcache_pampd_is_remote,
 };
 
 /*

@@ -1212,19 +1322,20 @@ static struct shrinker zcache_shrinker =
  * zcache shims between cleancache/frontswap ops and tmem
  */
 
-static int zcache_put_page(int pool_id, struct tmem_oid *oidp,
+static int zcache_put_page(int cli_id, int pool_id, struct tmem_oid *oidp,
 				uint32_t index, struct page *page)
 {
 	struct tmem_pool *pool;
 	int ret = -1;
 
 	BUG_ON(!irqs_disabled());
-	pool = zcache_get_pool_by_id(pool_id);
+	pool = zcache_get_pool_by_id(cli_id, pool_id);
 	if (unlikely(pool == NULL))
 		goto out;
 	if (!zcache_freeze && zcache_do_preload(pool) == 0) {
 		/* preload does preempt_disable on success */
-		ret = tmem_put(pool, oidp, index, page);
+		ret = tmem_put(pool, oidp, index, page_address(page),
+				PAGE_SIZE, 0, is_ephemeral(pool));
 		if (ret < 0) {
 			if (is_ephemeral(pool))
 				zcache_failed_eph_puts++;

@@ -1244,25 +1355,28 @@ out:
 	return ret;
 }
 
-static int zcache_get_page(int pool_id, struct tmem_oid *oidp,
+static int zcache_get_page(int cli_id, int pool_id, struct tmem_oid *oidp,
 				uint32_t index, struct page *page)
 {
 	struct tmem_pool *pool;
 	int ret = -1;
 	unsigned long flags;
+	size_t size = PAGE_SIZE;
 
 	local_irq_save(flags);
-	pool = zcache_get_pool_by_id(pool_id);
+	pool = zcache_get_pool_by_id(cli_id, pool_id);
 	if (likely(pool != NULL)) {
 		if (atomic_read(&pool->obj_count) > 0)
-			ret = tmem_get(pool, oidp, index, page);
+			ret = tmem_get(pool, oidp, index, page_address(page),
+					&size, 0, is_ephemeral(pool));
 		zcache_put_pool(pool);
 	}
 	local_irq_restore(flags);
 	return ret;
 }
 
-static int zcache_flush_page(int pool_id, struct tmem_oid *oidp, uint32_t index)
+static int zcache_flush_page(int cli_id, int pool_id,
+				struct tmem_oid *oidp, uint32_t index)
 {
 	struct tmem_pool *pool;
 	int ret = -1;

@@ -1270,7 +1384,7 @@ static int zcache_flush_page(int pool_id
 
 	local_irq_save(flags);
 	zcache_flush_total++;
-	pool = zcache_get_pool_by_id(pool_id);
+	pool = zcache_get_pool_by_id(cli_id, pool_id);
 	if (likely(pool != NULL)) {
 		if (atomic_read(&pool->obj_count) > 0)
 			ret = tmem_flush_page(pool, oidp, index);

@@ -1282,7 +1396,8 @@ static int zcache_flush_page(int pool_id
 	return ret;
 }
 
-static int zcache_flush_object(int pool_id, struct tmem_oid *oidp)
+static int zcache_flush_object(int cli_id, int pool_id,
+				struct tmem_oid *oidp)
 {
 	struct tmem_pool *pool;
 	int ret = -1;

@@ -1290,7 +1405,7 @@ static int zcache_flush_object(int pool_
 
 	local_irq_save(flags);
 	zcache_flobj_total++;
-	pool = zcache_get_pool_by_id(pool_id);
+	pool = zcache_get_pool_by_id(cli_id, pool_id);
 	if (likely(pool != NULL)) {
 		if (atomic_read(&pool->obj_count) > 0)
 			ret = tmem_flush_object(pool, oidp);

@@ -1302,34 +1417,52 @@ static int zcache_flush_object(int pool_
 	return ret;
 }
 
-static int zcache_destroy_pool(int pool_id)
+static int zcache_destroy_pool(int cli_id, int pool_id)
 {
 	struct tmem_pool *pool = NULL;
+	struct zcache_client *cli = NULL;
 	int ret = -1;
 
 	if (pool_id < 0)
 		goto out;
-	pool = zcache_client.tmem_pools[pool_id];
+	if (cli_id == LOCAL_CLIENT)
+		cli = &zcache_host;
+	else if ((unsigned int)cli_id < MAX_CLIENTS)
+		cli = &zcache_clients[cli_id];
+	if (cli == NULL)
+		goto out;
+	atomic_inc(&cli->refcount);
+	pool = cli->tmem_pools[pool_id];
 	if (pool == NULL)
 		goto out;
-	zcache_client.tmem_pools[pool_id] = NULL;
+	cli->tmem_pools[pool_id] = NULL;
 	/* wait for pool activity on other cpus to quiesce */
 	while (atomic_read(&pool->refcount) != 0)
 		;
+	atomic_dec(&cli->refcount);
 	local_bh_disable();
 	ret = tmem_destroy_pool(pool);
 	local_bh_enable();
 	kfree(pool);
-	pr_info("zcache: destroyed pool id=%d\n", pool_id);
+	pr_info("zcache: destroyed pool id=%d, cli_id=%d\n",
+			pool_id, cli_id);
 out:
 	return ret;
 }
 
-static int zcache_new_pool(uint32_t flags)
+static int zcache_new_pool(uint16_t cli_id, uint32_t flags)
 {
 	int poolid = -1;
 	struct tmem_pool *pool;
+	struct zcache_client *cli = NULL;
 
+	if (cli_id == LOCAL_CLIENT)
+		cli = &zcache_host;
+	else if ((unsigned int)cli_id < MAX_CLIENTS)
+		cli = &zcache_clients[cli_id];
+	if (cli == NULL)
+		goto out;
+	atomic_inc(&cli->refcount);
 	pool = kmalloc(sizeof(struct tmem_pool), GFP_KERNEL);
 	if (pool == NULL) {
 		pr_info("zcache: pool creation failed: out of memory\n");

@@ -1337,7 +1470,7 @@ static int zcache_new_pool(uint32_t flag
 	}
 
 	for (poolid = 0; poolid < MAX_POOLS_PER_CLIENT; poolid++)
-		if (zcache_client.tmem_pools[poolid] == NULL)
+		if (cli->tmem_pools[poolid] == NULL)
 			break;
 	if (poolid >= MAX_POOLS_PER_CLIENT) {
 		pr_info("zcache: pool creation failed: max exceeded\n");

@@ -1346,14 +1479,16 @@ static int zcache_new_pool(uint32_t flag
 		goto out;
 	}
 	atomic_set(&pool->refcount, 0);
-	pool->client = &zcache_client;
+	pool->client = cli;
 	pool->pool_id = poolid;
 	tmem_new_pool(pool, flags);
-	zcache_client.tmem_pools[poolid] = pool;
-	pr_info("zcache: created %s tmem pool, id=%d\n",
+	cli->tmem_pools[poolid] = pool;
+	pr_info("zcache: created %s tmem pool, id=%d, client=%d\n",
 		flags & TMEM_POOL_PERSIST ? "persistent" : "ephemeral",
-		poolid);
+		poolid, cli_id);
 out:
+	if (cli != NULL)
+		atomic_dec(&cli->refcount);
 	return poolid;
 }
 

@@ -1374,7 +1509,7 @@ static void zcache_cleancache_put_page(i
 	struct tmem_oid oid = *(struct tmem_oid *)&key;
 
 	if (likely(ind == index))
-		(void)zcache_put_page(pool_id, &oid, index, page);
+		(void)zcache_put_page(LOCAL_CLIENT, pool_id, &oid, index, page);
 }
 
 static int zcache_cleancache_get_page(int pool_id,

@@ -1386,7 +1521,7 @@ static int zcache_cleancache_get_page(in
 	int ret = -1;
 
 	if (likely(ind == index))
-		ret = zcache_get_page(pool_id, &oid, index, page);
+		ret = zcache_get_page(LOCAL_CLIENT, pool_id, &oid, index, page);
 	return ret;
 }
 

@@ -1398,7 +1533,7 @@ static void zcache_cleancache_flush_page
 	struct tmem_oid oid = *(struct tmem_oid *)&key;
 
 	if (likely(ind == index))
-		(void)zcache_flush_page(pool_id, &oid, ind);
+		(void)zcache_flush_page(LOCAL_CLIENT, pool_id, &oid, ind);
 }
 
 static void zcache_cleancache_flush_inode(int pool_id,

@@ -1406,13 +1541,13 @@ static void zcache_cleancache_flush_inod
 {
 	struct tmem_oid oid = *(struct tmem_oid *)&key;
 
-	(void)zcache_flush_object(pool_id, &oid);
+	(void)zcache_flush_object(LOCAL_CLIENT, pool_id, &oid);
 }
 
 static void zcache_cleancache_flush_fs(int pool_id)
 {
 	if (pool_id >= 0)
-		(void)zcache_destroy_pool(pool_id);
+		(void)zcache_destroy_pool(LOCAL_CLIENT, pool_id);
 }
 
 static int zcache_cleancache_init_fs(size_t pagesize)

@@ -1420,7 +1555,7 @@ static int zcache_cleancache_init_fs(siz
 	BUG_ON(sizeof(struct cleancache_filekey) !=
 				sizeof(struct tmem_oid));
 	BUG_ON(pagesize != PAGE_SIZE);
-	return zcache_new_pool(0);
+	return zcache_new_pool(LOCAL_CLIENT, 0);
 }
 
 static int zcache_cleancache_init_shared_fs(char *uuid, size_t pagesize)

@@ -1429,7 +1564,7 @@ static int zcache_cleancache_init_shared
 	BUG_ON(sizeof(struct cleancache_filekey) !=
 				sizeof(struct tmem_oid));
 	BUG_ON(pagesize != PAGE_SIZE);
-	return zcache_new_pool(0);
+	return zcache_new_pool(LOCAL_CLIENT, 0);
 }
 
 static struct cleancache_ops zcache_cleancache_ops = {

@@ -1483,8 +1618,8 @@ static int zcache_frontswap_put_page(uns
 	BUG_ON(!PageLocked(page));
 	if (likely(ind64 == ind)) {
 		local_irq_save(flags);
-		ret = zcache_put_page(zcache_frontswap_poolid, &oid,
-					iswiz(ind), page);
+		ret = zcache_put_page(LOCAL_CLIENT, zcache_frontswap_poolid,
+					&oid, iswiz(ind), page);
 		local_irq_restore(flags);
 	}
 	return ret;

@@ -1502,8 +1637,8 @@ static int zcache_frontswap_get_page(uns
 
 	BUG_ON(!PageLocked(page));
 	if (likely(ind64 == ind))
-		ret = zcache_get_page(zcache_frontswap_poolid, &oid,
-					iswiz(ind), page);
+		ret = zcache_get_page(LOCAL_CLIENT, zcache_frontswap_poolid,
+					&oid, iswiz(ind), page);
 	return ret;
 }
 

@@ -1515,8 +1650,8 @@ static void zcache_frontswap_flush_page(
 	struct tmem_oid oid = oswiz(type, ind);
 
 	if (likely(ind64 == ind))
-		(void)zcache_flush_page(zcache_frontswap_poolid, &oid,
-					iswiz(ind));
+		(void)zcache_flush_page(LOCAL_CLIENT, zcache_frontswap_poolid,
+					&oid, iswiz(ind));
 }
 
 /* flush all pages from the passed swaptype */

@@ -1527,7 +1662,8 @@ static void zcache_frontswap_flush_area(
 
 	for (ind = SWIZ_MASK; ind >= 0; ind--) {
 		oid = oswiz(type, ind);
-		(void)zcache_flush_object(zcache_frontswap_poolid, &oid);
+		(void)zcache_flush_object(LOCAL_CLIENT,
+						zcache_frontswap_poolid, &oid);
 	}
 }
 

@@ -1535,7 +1671,8 @@ static void zcache_frontswap_init(unsign
 {
 	/* a single tmem poolid is used for all frontswap "types" (swapfiles) */
 	if (zcache_frontswap_poolid < 0)
-		zcache_frontswap_poolid = zcache_new_pool(TMEM_POOL_PERSIST);
+		zcache_frontswap_poolid =
+			zcache_new_pool(LOCAL_CLIENT, TMEM_POOL_PERSIST);
 }
 
 static struct frontswap_ops zcache_frontswap_ops = {

@@ -1624,6 +1761,11 @@ static int __init zcache_init(void)
 				sizeof(struct tmem_objnode), 0, 0, NULL);
 	zcache_obj_cache = kmem_cache_create("zcache_obj",
 				sizeof(struct tmem_obj), 0, 0, NULL);
+	ret = zcache_new_client(LOCAL_CLIENT);
+	if (ret) {
+		pr_err("zcache: can't create client\n");
+		goto out;
+	}
 #endif
 #ifdef CONFIG_CLEANCACHE
 	if (zcache_enabled && use_cleancache) {

@@ -1642,11 +1784,6 @@ static int __init zcache_init(void)
 	if (zcache_enabled && use_frontswap) {
 		struct frontswap_ops old_ops;
 
-		zcache_client.xvpool = xv_create_pool();
-		if (zcache_client.xvpool == NULL) {
-			pr_err("zcache: can't create xvpool\n");
-			goto out;
-		}
 		old_ops = zcache_frontswap_register_ops();
 		pr_info("zcache: frontswap enabled using kernel "
 			"transcendent memory and xvmalloc\n");