staging: zsmalloc: change ZS_MIN_ALLOC_SIZE

This patch ensures that the value of ZS_MIN_ALLOC_SIZE, for the
PAGE_SIZE and MAX_PHYSMEM_BITS on the system, allows for all
possible object ids in the lowest storage class to be encoded
in the object handle.

Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/zsmalloc/zsmalloc_int.h b/drivers/staging/zsmalloc/zsmalloc_int.h
index ffb272f8934318220eb05582353d0cf7cd2aa532..92eefc663afc3336f73a8114f9c5543301bd1819 100644 (file)
--- a/drivers/staging/zsmalloc/zsmalloc_int.h
+++ b/drivers/staging/zsmalloc/zsmalloc_int.h
@@ -58,8 +58,10 @@
 #define OBJ_INDEX_BITS (BITS_PER_LONG - _PFN_BITS)
 #define OBJ_INDEX_MASK ((_AC(1, UL) << OBJ_INDEX_BITS) - 1)
 
+#define MAX(a, b) ((a) >= (b) ? (a) : (b))
 /* ZS_MIN_ALLOC_SIZE must be multiple of ZS_ALIGN */
-#define ZS_MIN_ALLOC_SIZE      32
+#define ZS_MIN_ALLOC_SIZE \
+       MAX(32, (ZS_MAX_PAGES_PER_ZSPAGE << PAGE_SHIFT >> OBJ_INDEX_BITS))
 #define ZS_MAX_ALLOC_SIZE      PAGE_SIZE
 
 /*