Revert "ramster: switch over to zsmalloc and crypto interface"

This reverts commit 49b81a3c.

It causes build breakage under some configurations.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ramster/Kconfig

 config RAMSTER
 	bool "Cross-machine RAM capacity sharing, aka peer-to-peer tmem"
-	depends on (CLEANCACHE || FRONTSWAP) && CONFIGFS_FS=y && !ZCACHE && CRYPTO=y && !HIGHMEM && NET
-	select ZSMALLOC
-	select CRYPTO_LZO
+	depends on (CLEANCACHE || FRONTSWAP) && CONFIGFS_FS=y && !ZCACHE && !XVMALLOC && !HIGHMEM && NET
+	select LZO_COMPRESS
+	select LZO_DECOMPRESS
 	default n
 	help
 	  RAMster allows RAM on other machines in a cluster to be utilized

drivers/staging/ramster/Makefile

-obj-$(CONFIG_RAMSTER)	+=	zcache-main.o tmem.o r2net.o cluster/
+obj-$(CONFIG_RAMSTER)	+=	zcache-main.o tmem.o r2net.o xvmalloc.o cluster/

drivers/staging/ramster/TODO

 For this staging driver, RAMster duplicates code from drivers/staging/zcache
-then incorporates changes to the local copy of the code.
+then incorporates changes to the local copy of the code.  For V5, it also
+directly incorporates the soon-to-be-removed drivers/staging/zram/xvmalloc.[ch]
+as all testing has been done with xvmalloc rather than the new zsmalloc.
 Before RAMster can be promoted from staging, the zcache and RAMster drivers
 should be either merged or reorganized to separate out common code.
 

drivers/staging/ramster/xvmalloc.h

+/*
+ * xvmalloc memory allocator
+ *
+ * Copyright (C) 2008, 2009, 2010  Nitin Gupta
+ *
+ * This code is released using a dual license strategy: BSD/GPL
+ * You can choose the licence that better fits your requirements.
+ *
+ * Released under the terms of 3-clause BSD License
+ * Released under the terms of GNU General Public License Version 2.0
+ */
+
+#ifndef _XV_MALLOC_H_
+#define _XV_MALLOC_H_
+
+#include <linux/types.h>
+
+struct xv_pool;
+
+struct xv_pool *xv_create_pool(void);
+void xv_destroy_pool(struct xv_pool *pool);
+
+int xv_malloc(struct xv_pool *pool, u32 size, struct page **page,
+			u32 *offset, gfp_t flags);
+void xv_free(struct xv_pool *pool, struct page *page, u32 offset);
+
+u32 xv_get_object_size(void *obj);
+u64 xv_get_total_size_bytes(struct xv_pool *pool);
+
+#endif

drivers/staging/ramster/xvmalloc_int.h

+/*
+ * xvmalloc memory allocator
+ *
+ * Copyright (C) 2008, 2009, 2010  Nitin Gupta
+ *
+ * This code is released using a dual license strategy: BSD/GPL
+ * You can choose the licence that better fits your requirements.
+ *
+ * Released under the terms of 3-clause BSD License
+ * Released under the terms of GNU General Public License Version 2.0
+ */
+
+#ifndef _XV_MALLOC_INT_H_
+#define _XV_MALLOC_INT_H_
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+/* User configurable params */
+
+/* Must be power of two */
+#ifdef CONFIG_64BIT
+#define XV_ALIGN_SHIFT 3
+#else
+#define XV_ALIGN_SHIFT	2
+#endif
+#define XV_ALIGN	(1 << XV_ALIGN_SHIFT)
+#define XV_ALIGN_MASK	(XV_ALIGN - 1)
+
+/* This must be greater than sizeof(link_free) */
+#define XV_MIN_ALLOC_SIZE	32
+#define XV_MAX_ALLOC_SIZE	(PAGE_SIZE - XV_ALIGN)
+
+/*
+ * Free lists are separated by FL_DELTA bytes
+ * This value is 3 for 4k pages and 4 for 64k pages, for any
+ * other page size, a conservative (PAGE_SHIFT - 9) is used.
+ */
+#if PAGE_SHIFT == 16
+#define FL_DELTA_SHIFT 4
+#else
+#define FL_DELTA_SHIFT (PAGE_SHIFT - 9)
+#endif
+#define FL_DELTA	(1 << FL_DELTA_SHIFT)
+#define FL_DELTA_MASK	(FL_DELTA - 1)
+#define NUM_FREE_LISTS	((XV_MAX_ALLOC_SIZE - XV_MIN_ALLOC_SIZE) \
+				/ FL_DELTA + 1)
+
+#define MAX_FLI		DIV_ROUND_UP(NUM_FREE_LISTS, BITS_PER_LONG)
+
+/* End of user params */
+
+enum blockflags {
+	BLOCK_FREE,
+	PREV_FREE,
+	__NR_BLOCKFLAGS,
+};
+
+#define FLAGS_MASK	XV_ALIGN_MASK
+#define PREV_MASK	(~FLAGS_MASK)
+
+struct freelist_entry {
+	struct page *page;
+	u16 offset;
+	u16 pad;
+};
+
+struct link_free {
+	struct page *prev_page;
+	struct page *next_page;
+	u16 prev_offset;
+	u16 next_offset;
+};
+
+struct block_header {
+	union {
+		/* This common header must be XV_ALIGN bytes */
+		u8 common[XV_ALIGN];
+		struct {
+			u16 size;
+			u16 prev;
+		};
+	};
+	struct link_free link;
+};
+
+struct xv_pool {
+	ulong flbitmap;
+	ulong slbitmap[MAX_FLI];
+	u64 total_pages;	/* stats */
+	struct freelist_entry freelist[NUM_FREE_LISTS];
+	spinlock_t lock;
+};
+
+#endif